AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 625 PM EST SUN MAR 26 2006 .AVIATION... DIURNAL CUMULUS DISSIPATING RAPIDLY THIS EVENING AS SUN SETS. WINDS ALSO BECOMING LIGHT. LITTLE BIT OF CU LEFT OVER NORTHEAST INDIANA WITH WEAK UPPER CIRCULATION. THIS COULD ROTATE INTO KFWA FROM TIME TO TIME NEXT FEW HOURS SO WILL ACCOUNT FOR THIS WITH A BROKEN VFR TEMPO GROUP. SOME PATCHY FOG POSSIBLE OVERNIGHT WITH CLEAR SKIES AND LIGHT WINDS. DRIER AIR UPSTREAM SHOULD ADVECT IN AND LOWER DEWPOINTS SO COUNTING ON THIS TO KEEP WIDESPREAD FOG FROM FORMING. HIGH MOVES OVER AREA THROUGH MONDAY AFTERNOON BEFORE THICKENING AND LOWERING CLOUDS MOVE IN. CHANCES FOR PRECIPITATION BEFORE 00Z SLIM AND NOT WORTH A MENTION IN TAFS AT THIS POINT. && .SHORT TERM... TONIGHT AND MONDAY RATHER BENIGN SHORT TERM WEATHER AS SURFACE AND UPPER LEVEL RIDGING MOVE INTO THE AREA TONIGHT. FORECAST CHALLENGE WILL ACTUALLY BE CLOUD COVER EARLY THIS EVENING DUE TO WIDESPREAD INSTABILITY CUMULUS AND RESIDUAL STRATOCUMULUS ASSOCIATED WITH SLOW MOVING VORT MAX ALONG SOUTHEAST SHORE OF LAKE MICHIGAN. MODELS DID A POOR JOB HANDLING THIS VORTICITY MAX AND ASSOCIATED CLOUD COVER. VISIBLE SATELLITE LOOPS SHOW NICE CIRCULATION MOVING SOUTH ALONG THE EASTERN SHORE OF LAKE MICHIGAN. AT 19Z THIS CIRCULATION WAS JUST OFFSHORE OF HOLLAND MICHIGAN AND APPEARED TO BE DRIFTING A BIT SOUTHWEST. LATEST RUC40 EVEN STRUGGLING WITH A POSITION SOUTH OF CHICAGO AT 19Z...THOUGH IT DOES HAVE AN ELONGATED AXIS OF VORTICITY NORTHEAST THROUGH SOUTHERN MICHIGAN. A SECONDARY VORT MAX HAS SHOWN UP IN THE CU FIELD THIS AFTERNOON NEAR THE TRI STATE BORDER AREA. THIS CIRCULATION HAS BEEN SLOW TO MOVE BUT AIDING IN CONVERGENCE AND CUMULUS DEVELOPMENT THIS AFTERNOON. MOST OF THE CU FIELD IS VERY CELLULAR IN NATURE AND EXPECT ITS DISSIPATION WITH SUNSET AS DIURNAL HEATING IS LOST. THIS SHOULD LEAVE A SMALL AREA OF CLOUDS DIRECTLY ASSOCIATED WITH THE VORT MAX OVER THE NORTHWEST AREA. AS VORT MAX SINKS SOUTH AND SUBSIDENCE FROM RIDGING MOVES IN...FEEL THIS AREA WILL GRADUALLY DISSIPATE AS WELL. WILL HAVE REMAINDER OF AFTERNOON HOURS AS MOSTLY CLOUDY AND DECREASE MOST OF THE CLOUDS THROUGH 01Z...TRENDING TO MOSTLY CLEAR BY MID EVENING. WITH THE RIDGE DIRECTLY OVER TOP SHOULD SEE WINDS BECOME CALM ALONG WITH THE MOSTLY CLEAR SKIES. THIS SHOULD ALLOW FOR GOOD RADIATIONAL COOLING TONIGHT WITH LOW TEMPERATURES A FEW DEGREES BELOW COOLEST MOS...INTO THE MIDDLE 20S. MONDAY WILL BEGIN NICE WITH LIGHT WINDS AND MOSTLY SUNNY SKIES IN THE MORNING. NEXT SHORT WAVE WILL APPROACH WITH HIGH CLOUDS INCREASING DURING THE AFTERNOON. TEMPERATURES SHOULD APPROACH NORMAL VALUES IN THE MID 50S BEFORE THICKEST CLOUD COVER REACHES THE AREA. WHILE LOW LEVELS REMAIN RATHER DRY FOR MOST OF THE DAY...SATURATION DOES BEGIN TO OCCUR TOWARD 00Z SO HAVE LEFT THE SMALL CHANCE OF LIGHT SHOWERS IN THE FAR WEST STARTING AFTER 21Z. && .LONG TERM... MONDAY NIGHT THROUGH SUNDAY ANOTHER SIGNIFICANT PATTERN EVOLUTION WILL BE UNDERWAY IN THE MEDIUM RANGE PERIOD WHICH WILL ALLOW TEMPERATURES TO SWING FROM THE CURRENT BELOW AVERAGE VALUES TO ABOVE NORMAL BY MID WEEK. CURRENT PATTERN IS TYPICAL OF AN END STAGE MATURE -AO EPISODE WITH ALL THE NEGATIVE HEIGHT ANOMALIES IN THE NORTHERN HEMISPHERE CLUSTERED WITHIN A BELT IN THE MID LATITUDES WITH THE HIGH LATITUDES AND THE ARCTIC DOMINATED BY POSITIVE HEIGHT ANOMALIES. AS THIS LATEST PATTERN REGIME FADES THE BLOCKING PATTERN WHICH HAS BEEN IN PLACE ACROSS NOAM WILL BREAK DOWN WITH THE PERSISTENT COLD CLOSED LOW OVER THE GREAT LAKES FINALLY EJECTING OFF THE EAST COAST. AS THIS BLOCKING PATTERN BREAKS DOWN A PARADE OF SIGNIFICANT WAVES OF PACIFIC ORIGIN WILL BEGIN TO PROGRESS FROM WEST TO EAST ACROSS NOAM. IN ADDITION... SIGNIFICANT TROPICAL FORCING MANIFESTED IN WATER VAPOR IMAGERY AS A PLUME OF MOISTURE EXTENDING ACROSS THE HAWAIIAN ISLANDS WILL LIKELY CONTRIBUTE MOISTURE AND WAVE PACKETS TO THE PACIFIC WAVE TRAIN. LOOKING AT THE DAILIES THE FIRST IN A SERIES OF PACIFIC WAVES IS NOW CROSSING THROUGH THE INTERMOUNTAIN WEST AND WILL REMAIN PROGRESSIVE AS THE LAST VESTIGE OF THE CENTRAL CONUS OMEGA BLOCK QUICKLY DISSOLVES. NAM/GFS IN GOOD AGREEMENT NOW IN TAKING A CLOSED MID LEVEL LOW FROM CENTRAL ILLINOIS TO SOUTHERN OHIO MON NGT AND TUE. MID LEVEL LOW AND SURFACE REFLECTION WILL BE STEADILY FILLING AS THEY CROSS THE REGION WITH AN OVERALL WEAKENING IN DYNAMICS WITH TIME. NONETHELESS A PERIOD OF DPVA AHEAD OF THE WAVE COUPLED WITH FRONTOGENETICAL FORCING ALONG THE NORTHERN PERIPHERY OF THE LOW TRACK WILL PRODUCE A PERIOD OF RAIN ACROSS THE CWA FROM MON EVENING THROUGH TUE MORNING. ANY PRECIP WILL FALL AS LIQUID GIVEN THE SIGNIFICANT WARM LAYER IN THE LOWEST LEVELS PROMOTING FULL MELTING. HAVE INCREASED POPS TO HIGH LIKELY FOR MON NGT AND ALSO INCREASED POPS TO LIKELY OVER THE OHIO COUNTIES FOR TUE MORNING. ANY RAIN SHOULD END LATER TUE WITH A SURFACE HIGH BUILDING IN FOR TUE NGT AND WED. GIVEN PATTERN RECOGNITION OF A FILLING LOW AND MODEL SOUNDINGS...EXPECT SIGNIFICANT LOW LEVEL MOISTURE AND CLOUD COVER TO LINGER TUE NGT AND EVEN INTO WED MORNING. NEXT SIGNIFICANT WAVE NOW CROSSING THE GULF OF ALASKA WILL EMERGE ONTO THE HIGH PLAINS WED NGT. MEDIUM RANGE GUIDANCE IS COMING INTO REASONABLE AGREEMENT WITH THE MOVEMENT OF THIS FEATURE. BOTH THE GEM ENSEMBLES AND GFS ENSEMBLES SHOWING A MAJORITY CLUSTERING OF MEMBERS AROUND A COMMON PATH THROUGH THE UPPER MIDWEST WITH THE LATEST OPERATIONAL RUNS WELL WITHIN THE ENSEMBLE ENVELOPE. BASIC EVOLUTION WILL TAKE A STRONG MID LEVEL TROUGH AND SWING IT THROUGH THE PLAINS AND UPPER MISSISSIPPI VALLEY THU THROUGH FRI WITH A TRAILING COLD FRONT CROSSING OUR REGION ON FRIDAY. AS IS TYPICALLY THE CASE IN THE OHIO VALLEY...MEDIUM RANGE GUIDANCE CONTINUES TO SUGGEST PRE-FRONTAL TROUGH DEVELOPMENT WILL OCCUR AND BE THE FOCUS FOR CONVECTION. CURRENT GRIDS HAVE THE SITUATION WELL IN HAND AND WILL MAKE VERY FEW CHANGES. CHANCE OF TSRA CONTINUES IN THE FORECAST FOR THU NGT THROUGH FRI WITH A CHANCE OF LINGERING SHRA FRI NGT. IF FUTURE MODEL ITERATIONS CONTINUE TO SUGGEST FASTER MOTION...CHANCE OF THUNDERSTORMS MAY NEED TO BE INTRODUCED THU AFTERNOON AS WELL. NEXT WEEKEND MODEL AGREEMENT BEGINS TO DECREASE RAPIDLY...WHICH IS TYPICAL OF A TRANSITIONAL PATTERN IN SPRING. GIVEN THE IMPRESSIVE LOOKING PACIFIC WAVE TRAIN AND ONGOING TROPICAL FORCING CONNECTION IN THE PACIFIC SUSPECT THERE WILL BE A THIRD SYSTEM POSSIBLY DAY 7 OR DAY 8 /SUN OR MON/. GIVEN THE DEGREE OF SPREAD AMONGST ENSEMBLE GUIDANCE WILL OPT TO HOLD OFF ON INCLUSION OF POPS FOR NOW. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SHORT TERM/AVIATION...LASHLEY LONG TERM....HITCHCOCK in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 249 PM EST SUN MAR 26 2006 .SHORT TERM... TONIGHT AND MONDAY RATHER BENIGN SHORT TERM WEATHER AS SURFACE AND UPPER LEVEL RIDGING MOVE INTO THE AREA TONIGHT. FORECAST CHALLENGE WILL ACTUALLY BE CLOUD COVER EARLY THIS EVENING DUE TO WIDESPREAD INSTABILITY CUMULUS AND RESIDUAL STRATOCUMULUS ASSOCIATED WITH SLOW MOVING VORT MAX ALONG SOUTHEAST SHORE OF LAKE MICHIGAN. MODELS DID A POOR JOB HANDLING THIS VORTICITY MAX AND ASSOCIATED CLOUD COVER. VISIBLE SATELLITE LOOPS SHOW NICE CIRCULATION MOVING SOUTH ALONG THE EASTERN SHORE OF LAKE MICHIGAN. AT 19Z THIS CIRCULATION WAS JUST OFFSHORE OF HOLLAND MICHIGAN AND APPEARED TO BE DRIFTING A BIT SOUTHWEST. LATEST RUC40 EVEN STRUGGLING WITH A POSITION SOUTH OF CHICAGO AT 19Z...THOUGH IT DOES HAVE AN ELONGATED AXIS OF VORTICITY NORTHEAST THROUGH SOUTHERN MICHIGAN. A SECONDARY VORT MAX HAS SHOWN UP IN THE CU FIELD THIS AFTERNOON NEAR THE TRI STATE BORDER AREA. THIS CIRCULATION HAS BEEN SLOW TO MOVE BUT AIDING IN CONVERGENCE AND CUMULUS DEVELOPMENT THIS AFTERNOON. MOST OF THE CU FIELD IS VERY CELLULAR IN NATURE AND EXPECT ITS DISSIPATION WITH SUNSET AS DIURNAL HEATING IS LOST. THIS SHOULD LEAVE A SMALL AREA OF CLOUDS DIRECTLY ASSOCIATED WITH THE VORT MAX OVER THE NORTHWEST AREA. AS VORT MAX SINKS SOUTH AND SUBSIDENCE FROM RIDGING MOVES IN...FEEL THIS AREA WILL GRADUALLY DISSIPATE AS WELL. WILL HAVE REMAINDER OF AFTERNOON HOURS AS MOSTLY CLOUDY AND DECREASE MOST OF THE CLOUDS THROUGH 01Z...TRENDING TO MOSTLY CLEAR BY MID EVENING. WITH THE RIDGE DIRECTLY OVER TOP SHOULD SEE WINDS BECOME CALM ALONG WITH THE MOSTLY CLEAR SKIES. THIS SHOULD ALLOW FOR GOOD RADIATIONAL COOLING TONIGHT WITH LOW TEMPERATURES A FEW DEGREES BELOW COOLEST MOS...INTO THE MIDDLE 20S. MONDAY WILL BEGIN NICE WITH LIGHT WINDS AND MOSTLY SUNNY SKIES IN THE MORNING. NEXT SHORT WAVE WILL APPROACH WITH HIGH CLOUDS INCREASING DURING THE AFTERNOON. TEMPERATURES SHOULD APPROACH NORMAL VALUES IN THE MID 50S BEFORE THICKEST CLOUD COVER REACHES THE AREA. WHILE LOW LEVELS REMAIN RATHER DRY FOR MOST OF THE DAY...SATURATION DOES BEGIN TO OCCUR TOWARD 00Z SO HAVE LEFT THE SMALL CHANCE OF LIGHT SHOWERS IN THE FAR WEST STARTING AFTER 21Z. && .LONG TERM... MONDAY NIGHT THROUGH SUNDAY ANOTHER SIGNIFICANT PATTERN EVOLUTION WILL BE UNDERWAY IN THE MEDIUM RANGE PERIOD WHICH WILL ALLOW TEMPERATURES TO SWING FROM THE CURRENT BELOW AVERAGE VALUES TO ABOVE NORMAL BY MID WEEK. CURRENT PATTERN IS TYPICAL OF AN END STAGE MATURE -AO EPISODE WITH ALL THE NEGATIVE HEIGHT ANOMALIES IN THE NORTHERN HEMISPHERE CLUSTERED WITHIN A BELT IN THE MID LATITUDES WITH THE HIGH LATITUDES AND THE ARCTIC DOMINATED BY POSITIVE HEIGHT ANOMALIES. AS THIS LATEST PATTERN REGIME FADES THE BLOCKING PATTERN WHICH HAS BEEN IN PLACE ACROSS NOAM WILL BREAK DOWN WITH THE PERSISTENT COLD CLOSED LOW OVER THE GREAT LAKES FINALLY EJECTING OFF THE EAST COAST. AS THIS BLOCKING PATTERN BREAKS DOWN A PARADE OF SIGNIFICANT WAVES OF PACIFIC ORIGIN WILL BEGIN TO PROGRESS FROM WEST TO EAST ACROSS NOAM. IN ADDITION... SIGNIFICANT TROPICAL FORCING MANIFESTED IN WATER VAPOR IMAGERY AS A PLUME OF MOISTURE EXTENDING ACROSS THE HAWAIIAN ISLANDS WILL LIKELY CONTRIBUTE MOISTURE AND WAVE PACKETS TO THE PACIFIC WAVE TRAIN. LOOKING AT THE DAILIES THE FIRST IN A SERIES OF PACIFIC WAVES IS NOW CROSSING THROUGH THE INTERMOUNTAIN WEST AND WILL REMAIN PROGRESSIVE AS THE LAST VESTIGE OF THE CENTRAL CONUS OMEGA BLOCK QUICKLY DISSOLVES. NAM/GFS IN GOOD AGREEMENT NOW IN TAKING A CLOSED MID LEVEL LOW FROM CENTRAL ILLINOIS TO SOUTHERN OHIO MON NGT AND TUE. MID LEVEL LOW AND SURFACE REFLECTION WILL BE STEADILY FILLING AS THEY CROSS THE REGION WITH AN OVERALL WEAKENING IN DYNAMICS WITH TIME. NONETHELESS A PERIOD OF DPVA AHEAD OF THE WAVE COUPLED WITH FRONTOGENETICAL FORCING ALONG THE NORTHERN PERIPHERY OF THE LOW TRACK WILL PRODUCE A PERIOD OF RAIN ACROSS THE CWA FROM MON EVENING THROUGH TUE MORNING. ANY PRECIP WILL FALL AS LIQUID GIVEN THE SIGNIFICANT WARM LAYER IN THE LOWEST LEVELS PROMOTING FULL MELTING. HAVE INCREASED POPS TO HIGH LIKELY FOR MON NGT AND ALSO INCREASED POPS TO LIKELY OVER THE OHIO COUNTIES FOR TUE MORNING. ANY RAIN SHOULD END LATER TUE WITH A SURFACE HIGH BUILDING IN FOR TUE NGT AND WED. GIVEN PATTERN RECOGNITION OF A FILLING LOW AND MODEL SOUNDINGS...EXPECT SIGNIFICANT LOW LEVEL MOISTURE AND CLOUD COVER TO LINGER TUE NGT AND EVEN INTO WED MORNING. NEXT SIGNIFICANT WAVE NOW CROSSING THE GULF OF ALASKA WILL EMERGE ONTO THE HIGH PLAINS WED NGT. MEDIUM RANGE GUIDANCE IS COMING INTO REASONABLE AGREEMENT WITH THE MOVEMENT OF THIS FEATURE. BOTH THE GEM ENSEMBLES AND GFS ENSEMBLES SHOWING A MAJORITY CLUSTERING OF MEMBERS AROUND A COMMON PATH THROUGH THE UPPER MIDWEST WITH THE LATEST OPERATIONAL RUNS WELL WITHIN THE ENSEMBLE ENVELOPE. BASIC EVOLUTION WILL TAKE A STRONG MID LEVEL TROUGH AND SWING IT THROUGH THE PLAINS AND UPPER MISSISSIPPI VALLEY THU THROUGH FRI WITH A TRAILING COLD FRONT CROSSING OUR REGION ON FRIDAY. AS IS TYPICALLY THE CASE IN THE OHIO VALLEY...MEDIUM RANGE GUIDANCE CONTINUES TO SUGGEST PRE-FRONTAL TROUGH DEVELOPMENT WILL OCCUR AND BE THE FOCUS FOR CONVECTION. CURRENT GRIDS HAVE THE SITUATION WELL IN HAND AND WILL MAKE VERY FEW CHANGES. CHANCE OF TSRA CONTINUES IN THE FORECAST FOR THU NGT THROUGH FRI WITH A CHANCE OF LINGERING SHRA FRI NGT. IF FUTURE MODEL ITERATIONS CONTINUE TO SUGGEST FASTER MOTION...CHANCE OF THUNDERSTORMS MAY NEED TO BE INTRODUCED THU AFTERNOON AS WELL. NEXT WEEKEND MODEL AGREEMENT BEGINS TO DECREASE RAPIDLY...WHICH IS TYPICAL OF A TRANSITIONAL PATTERN IN SPRING. GIVEN THE IMPRESSIVE LOOKING PACIFIC WAVE TRAIN AND ONGOING TROPICAL FORCING CONNECTION IN THE PACIFIC SUSPECT THERE WILL BE A THIRD SYSTEM POSSIBLY DAY 7 OR DAY 8 /SUN OR MON/. GIVEN THE DEGREE OF SPREAD AMONGST ENSEMBLE GUIDANCE WILL OPT TO HOLD OFF ON INCLUSION OF POPS FOR NOW. && .AVIATION... FOR 18Z TAF ISSUANCE WILL CONTINUE WITH VFR CIGS THROUGH THE AFTERNOON AT BOTH KSBN AND KFWA. WINDS WILL BE A BIT STRONGER THAN PREVIOUSLY THOUGHT WITH GENERALLY 10 KTS FROM NORTHWEST. CLOUDS TO DECREASE TONIGHT AS WELL AS WINDS BECOMING CALM. DRIER AIR WORKING IN SHOULD KEEP DEWPOINTS DOWN AND KEEP ANY FOG FROM FORMING WITH THE CLEARING SKIES AND CALM WINDS OVERNIGHT. SEE ABOVE UPDATE DISCUSSION FOR DETAILS OF CLOUD COVERAGE THIS AFTERNOON. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SHORT TERM/AVIATION...LASHLEY LONG TERM....HITCHCOCK in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 815 PM MST SUN MAR 26 2006 .UPDATE...HAVE UPDATED GRIDS TO INCLUDE A WIND ADVISORY ACROSS FAR EASTERN COLORADO. THIS MAY HAVE TO BE EXPANDED FURTHER EAST. AT 03Z KAKO AS WELL AS YUMA COLORADO GUSTING OVER 50 MPH ON LEADING EDGE OF POSSIBLY SOME LIGHT SHOWERS BUT AS THE RUC ALSO POINTS OUT 40+KT 800 MB WINDS. LOW LEVEL LAPSE RATES ALSO RATHER HIGH...OVER 8C/KM. THROUGH 06Z THE CORE OF THE STRONGER WINDS MOVES SOUTHEAST TOWARD FAR WESTERN KANSAS AS THE TIGHTLY WOUND UPPER LOW CONTINUES EAST ACROSS NEBRASKA. HIGHEST CONFIDENCE RIGHT NOW IS FOR ADVISORY CRITERIA GUSTS (OVER 45 MPH) TO OCCUR ACROSS FAR EASTERN COLORADO. WILL NEED TO WATCH SHERMAN AND CHEYENNE COUNTIES OF KANSAS AS WELL AS DUNDY COUNTY NEBRASKA DURING THE NEXT FEW HOURS AS EVEN STRONGER WINDS ARE EXPECTED AT 800MB. HOW MUCH OF THAT WORKS TO THE SURFACE IS THE QUESTION RIGHT NOW. FURTHER UPDATES MAY BE NEEDED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...WIND ADVISORY UNTIL 11 PM MST THIS EVENING FOR COZ090- COZ091-COZ092. && $$ ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 1210 PM MST SUN MAR 26 2006 .UPDATE...LATEST OBSERVATIONS OVER EASTERN COLORADO INDICATE VERY WINDY CONDTIONS DEVELOPING THERE. THIS IS ALSO SUPPORTED BY STRONG SUDSIDENCE NOTED ON WATER VAPOR IMAGERY MOVING EAST OF THE COLORADO ROCKIES. THE RUC MODEL INDICATES THAT WINDS SHOULD REACH WIND ADVISORY SPEEDS THIS AFTERNOON THERE. CONSEQUENTLY HAVE ISSUED A WIND ADVISORY FOR THE EASTERN COLORADO ZONES UNTIL 00Z MON. THE RUC MODEL INDICATES THAT THESE STRONG WINDS SHOULD NOT DEVELOP OVER FAR WESTERN KANSAS AND EXTREME SOUTHWEST NEBRASKA ZONES. ALSO ADJUSTED MAX TEMPERATURES UP...ESPECIALLY OVER COLORADO ZONES...WHERE WINDS ARE PROVIDING GOOD MIXING AND TEMPERATURES ARE RISING INTO THE 60S. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...WIND ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR COZ090-COZ091- COZ092. && $$ FS ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOUISVILLE KY 1054 AM EST SUN MAR 26 2006 .MORNING UPDATE... FORECAST IS IN PRETTY GOOD SHAPE. VIS SAT SHOWING SOME DISSIPATING LOW STRATUS OVER THE FAR NERN CWA...WITH LOW-LEVEL CU FIELD BEGINNING TO DEVELOP CWA-WIDE. THIS TREND WILL LIKELY CONTINUE TODAY PER THE LATEST ETA AND RUC SOUNDINGS. SO WILL CONTINUE THE PARTLY SUNNY WORDING. TEMPS RANGING FROM NEAR 50 OVER NE TO MID 50S SW...MAYBE A FEW 56-57 DEGREE READINGS...LOOKS REASONABLE. CURRENT TEMPS ARE RUNNING ABOUT 5 DEGREES WARMER FROM YESTERDAY. TWEAKED TEMPS TO REFLECT THIS. OTHERWISE...NICE DAY WITH NORTHERLY WINDS 5-10 MPH. UPDATED FORECAST OUT SOON. AL && .PREV DISCUSSION... SHORT TERM (TODAY AND TONIGHT) THE COLD...CYCLONIC AND SOMEWHAT MOIST NWLY FLOW OF THE PAST COUPLE OF DAYS HAS BECOME DRIER AND MORE ANTICYCLONIC AS A SFC HIGH BUILDS INTO THE REGION TODAY. THE AIR CONTINUES TO SLOWLY DRY OUT IN THE LOWER LEVELS. THE MAIN FCST PROBLEMS FOR THE SHORT TERM IS DEALING WITH THE MIX OF CLOUDS AND SUN TODAY AND THE RESULTANT HIGH TEMPS. OVERNIGHT...HOW MUCH OF A RETURN TO SOUTHEASTERLY FLOW IN THE LOWER LEVELS TAKES PLACE BY MORNING UNDER MOSTLY CLEAR SKIES AND THE RESULTANT MIN TEMPS. ONLY SMALL TWEAKS TO THE CURRENT FCST TEMP TRENDS FOR TODAY AND TONIGHT. --21 LONG TERM (MONDAY THROUGH SATURDAY)... TWO WEATHER SYSTEMS WILL IMPACT CENTRAL KENTUCKY AND SOUTH CENTRAL INDIANA DURING THE LONG TERM. THE FIRST WILL COME LATE MONDAY AND MONDAY NIGHT INTO TUESDAY WITH THE SECOND THURSDAY AND FRIDAY INTO SATURDAY. MODELS ARE IN A LITTLE BETTER AGREEMENT BUT ECMWF SEEMS TO A LITTLE SLOWER...ESPECIALLY TOWARD THE END OF THE WEEK. WILL LEAN TOWARD THE FASTER GFS BUT WILL NOT GO AS HIGH ON POPS. MONDAY INTO TUESDAY...LOW PRESSURE ACCOMPANYING THIS FIRST SYSTEM WILL MOVE EAST ACROSS THE NORTHERN PLAINS THEN EAST SOUTHEAST INTO THE GREAT LAKES STATES. SOUTHERLY WINDS AROUND THE RETREATING HIGH PRESSURE AREA WILL BRING SOME INCREASE IN MOISTURE BUT WITH STRONGER 850 MB WINDS NOT HAVING MUCH TIME OUT OF THE GULF MOISTURE WILL BE SOMEWHAT LIMITED. SHOWERS WILL BE NUMEROUS BUT RAINFALL AMOUNTS WILL NOT BE ALL THAT HEAVY. HIGH PRESSURE WILL TRACK ACROSS THE AREA TUESDAY NIGHT AND WEDNESDAY. AS THIS HIGH MOVES TO THE ATLANTIC COAST...SOUTHERLY WINDS WILL DRAW WARMER AND MORE MOIST AIR NORTH FROM THE GULF. FLOW AT 850 MB IS MORE FAVORABLE FOR CARRYING MOISTURE NORTH FROM GULF AND WILL ALLOW DEW POINTS TO INCREASE AS A RESULT. THIS GREATER WARMTH AND HIGHER HUMIDITIES WILL AID IN DESTABILIZING AIRMASS AND WILL KEEP CHANCE OF THUNDERSTORMS IN FORECAST ALONG AND AHEAD OF THIS SYSTEM. LOOK FOR FRONTAL PASSAGE THURSDAY NIGHT. WILL CHANGE PRECIPITATION TYPE BACK TO SHOWERS FOR THE LAST HALF OF FRIDAY NIGHT. WARMER TEMPERATURES WILL SPREAD INTO THE AREA FOR THE MIDDLE AND LATTER HALF OF THE WEEK. SCHOLZ && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 1128 AM EST SUN MAR 26 2006 .SHORT TERM /REST OF TODAY/... WATER VAPOR IMAGERY SHOWS UPPER LOW SPINNING WELL OFFSHORE SOMEWHERE NEAR 41N 63W LATE THIS MORNING. HAVE A WIDE VARIETY OF CLOUD FORMATIONS ACROSS OUR CWA BASED ON VISIBLE AND INFRARED IMAGERY...WITH A SOLID DECK OF MID CLOUDS ACROSS THE BALTIMORE AND DC METRO AREAS...AND MORE IN THE WAY OF CU AND STRATOCU STREAKING ACROSS THE REST OF NORTH CENTRAL VA AND PLACES WEST OF THE BLUE RIDGE. NO MATTER THE TYPE (OR QUALITY) OF THE CLOUDS...THE QUANTITY DENOTES MOSTLY CLOUDY FOR JUST ABOUT OUR ENTIRE CWA THROUGH THE AFTERNOON WITH MID AND LOWER MOISTURE IN PLACE. A LITTLE MORE CHALLENGING IS WHETHER OR NOT TO HAVE ANY MENTION OF PRECIP THROUGH THE AFTERNOON. OROGRAPHICS WILL KEEP A FEW SNOW/RAIN SHOWERS ALONG AND WEST OF THE ALLEGANY FRONT THROUGH THIS AFTERNOON...AND WILL HAVE CHC POPS IN THIS AREA. KLWX 88D HAS BEEN DOWN THIS MORNING...YET SURROUNDING RADAR INFORMATION INCLUDING BWI TDWR INDICATED VERY WEAK RETURNS (NOT EVEN 10 DBZ) WRAPPING AROUND INTO THE CHESAPEAKE BAY ALONG A LOW LEVEL CONVERGENT ZONE. KDOV GIVES A LITTLE GROUND TRUTH TO THESE WEAK ECHOES WITH 7SM IN -RA. IN ADDITION...THE LATEST RUNS OF THE RUC AND NAM SHOW MOISTURE TO SUPPORT THIS LIGHT PRECIP IN ROUGHLY THE SAME AREA THAT RADAR TRENDS IMPLY. THEREFORE...EXPECT SIMILAR ECHOES TO THAT AFFECTING KDOV TO BRUSH THE BAY AND OUR EXTREME EASTERN CWA THIS AFTERNOON. WILL INSERT 20 POPS HERE...INCLUDING BALTIMORE CITY...THEN TAPER TO A N TO S ORIENTED STRIP OF SPRINKLES (POPS UNDER 15 HERE) THROUGH THE DISTRICT AND THEN NO WX POINTS WEST UNTIL ONE RUNS INTO THE CHC POPS DESCRIBED ABOVE ALONG AND WEST OF THE ALLEGANY FRONT. && .MARINE... INHERITED SCA ACROSS ALL MARINE WATERS. SENSORS ARE NOT SHOWING ANY SCA WINDS ATTM...AND HAVE SOME DOUBTS ON WHETHER WINDS CAN GET INTO SCA CRITERIA. NEVERTHELESS...BUFKIT IMPLIES THE POTENTIAL TO BOOST WINDS INTO THE 15 TO 20 KT RANGE THIS AFTERNOON AND WILL THEREFORE CONTINUE SCA. && .AVIATION... CU DECK SCT-BKN040 AND BKN-OVC150 PERSISTING OVER DCA...BWI... IAD...AND MTN WITH MAINLY CU TO THE WEST OVER CHO...MRB...AND HGR. EXPECT BKN040 TO BECOME WIDESPREAD OVER THE ENTIRE REGION WITH VFR CONDITIONS. BEST WIND GUSTS UP TO 20 KTS WILL BE IN VCTY OF ISOLATED -SHRA NEAR THE BAY AND OVER THE WESTERN RIDGES. FEEL CU WILL SCATTER OUT LATE THIS EVENING WITH LOSS OF INSOLATION. && .CLIMATOLOGY... WITH VERY LITTLE PRECIP SO FAR THIS MARCH WE ARE WELL ON OUR WAY TO A RECORD. WITH THE DEPARTING UPPER LOW THIS AFT AND ONE WAVE FCST TO APPROACH LATE TUE...ANY SIGNIFICANT PRECIP LOOKS MEAGER FOR THE REMAINDER OF MARCH. THIS IS HOW WE STAND AS OF THIS MORNING: SO FAR MARCH 2006 DRIEST MARCH DCA... 0.04 INCH 0.57 INCH 1910 BWI... 0.18 INCH 0.46 INCH 1910 IAD... 0.04 INCH 0.99 INCH 1981 THE US DROUGHT MONITOR AS OF MARCH 21ST CONTINUES TO SHOW ABNORMALLY DRY CONDITIONS ACROSS THE MID ATL REGION. D1 DROUGHT CONDITIONS EXIST ACROSS SW VA AND PARTS OF NC. INTERESTINGLY...APRIL 1910 IS THE FOURTH WETTEST ON RECORD AT BWI AND THE TENTH WETTEST AT DCA. && .PREV DISCUSSION... /ISSUED 410 AM EST SUN MAR 25 2006/ SHORT TERM...TODAY AND TONIGHT... SCATTERED SHOWERS CONTINUE IN THE FAVORED UPSLOPE AREAS IN NW FLOW. WILL CONTINUE TO MENTION CHANCE POPS IN THE WEST FOR UPSLOPE PRECIP. EXPECT ANY ADTNL ACCUMS BELOW 1 INCH IN THE HIGHER ELEVS. ELSEWHERE...EXPECT MOSTLY CLOUDY DUE TO AFTN CU DVLPNT ALTHOUGH PARTIAL SUNSHINE WILL BE EXPERIENCED. IN THE SOUTH EXPECT MORE SUNSHINE IN THE CENTRAL SHEN VLY. TEMPS WILL CONTINUE TO BE BELOW NORMAL WITH HIGHS ONLY IN THE 40S WEST TO THE LOWER 50S IN THE SOUTH AND EAST. HIGH PRES WILL BEGIN TO NOSE INTO THE MID ATLC TNGT AND AFTN CU SHOULD GRADUALLY DISSIPATE IN THE EVNG LEAVING MOSTLY CLEAR AND COOL CONDS OVERNGT. LONG TERM (MONDAY THROUGH SATURDAY)... OBSERVATIONS: 500MB HEIGHT/ANOMALY PATTERN DURING THE PAST 5 DAYS INDICATES THAT A STRONG UPPER LOW ACROSS THE CANADIAN MARITIMES HAS SHEARED INTO TWO...WITH THE MAJORITY OF ENERGY PASSING ACROSS THE ATLANTIC. A WEAK DISTURBANCE FROM THE SOUTHWEST CONUS HAS JOINED UP WITH THE AFOREMENTIONED LEFTOVER ENERGY TO ALLOW AN UPPER LOW TO DEVELOP ACROSS THE MID ATLANTIC. A BLOCKING PATTERN ACROSS THE PACIFIC OCEAN IS BEGINNING TO BREAK DOWN. WATER VAPOR LOOP SHOWS AN UPPER LOW ACROSS THE MID ATLANTIC...WITH A STRONG WAVE MOVING INTO THE CENTRAL ROCKIES. 03Z SURFACE ANALYSIS PLACES A WEAK BOUNDARY WNW INTO THE CHESAPEAKE BAY. A SECOND WEAK BOUNDARY EXTENDS SOUTHWEST ACROSS THE EASTERN GREAT LAKES. A PAIR OF 1027MB ANTICYCLONES DOMINATE THE CENTRAL CONUS. MODELS: THE 00Z NAM/WRF-NMM/GFS/CANADIAN/UKMET ALONG WITH THE 12Z EUROPEAN WERE EXAMINED. THERE IS GOOD AGREEMENT AMONG THE MODEL SUITE WITH RISING HEIGHTS EARLY THIS WEEK. A WAVE IS EXPECTED TO MOVE FROM THE EASTERN GREAT LAKES ACROSS THE NORTHERN MID ATLANTIC OR SOUTHERN NEW ENGLAND DURING THE MIDWEEK. AFTER ANOTHER ROUND OF RISING HEIGHTS LATE DURING THE WORK WEEK...MODELS SUGGEST ANOTHER WAVE APPROACHES THE EASTERN GREAT LAKES AT THE END OF THE FORECAST CYCLE. ENSEMBLES: 12Z GFS 500MB HEIGHT ENSEMBLES SHOW GOOD CONTINUITY WITH A PERIOD OF RISING HEIGHTS EARLY NEXT WEEK...WHILE ENSEMBLE MEMBERS INDICATE A TROUGH WILL PASS ACROSS SOUTHERN NEW ENGLAND BY MIDWEEK. ANOTHER RIDGE BUILDS IN...BEFORE ANOTHER TROUGH APPROACHES FROM THE MIDWEST TOWARD THE END OF THE FORECAST CYCLE (WITH BETTER AGREEMENT WITH REGARD TO TIMING). 00Z GFS ENSEMBLE MOS FROM FRIDAY EVENING SHOWS MEAN HIGH TEMPERATURES RISE FROM THE MIDDLE 50S INTO THE UPPER 60S BY FRIDAY...WITH MIDDLE 60S SATURDAY. MEAN LOWS RISE FROM NEAR 30 DEGREES INTO THE MIDDLE 40S (WITH GOOD CLUSTERING). MEAN POPS HOVER NEAR ZERO EARLY NEXT WEEK...THEN RISE BACK TO 20-30 PERCENT DURING THE MIDWEEK AND AGAIN EARLY NEXT WEEKEND (WITH DECENT AGREEMENT). FORECAST RATIONALE: CLOUDS BREAK WITH MODERATING TREND EARLY THIS WEEK. APPROACH OF THE NEXT WAVE SHOULD INCREASE CLOUDS AND PRESENT A CHANCE OF RAIN (OR RAIN/SNOW) TUESDAY INTO EARLY WEDNESDAY MORNING. A SECOND MODERATING TREND WILL SET UP FOR THE SECOND HALF OF THE WORK WEEK AS A AMPLIFIED RIDGE BUILDS INTO THE EASTERN CONUS. THIS PATTERN MAY SLOW THE APPROACH OF A LATE WEEK SYSTEM BEYOND THE VALID FORECAST CYCLE. CURRENT INDICATIONS ARE THAT A BAY BREEZE MAY DEVELOP THURSDAY (WEAK FLOW AS THE SURFACE RIDGE MOVES OFF THE EAST COAST...WITH STRONG WARMING ALONG THE LAND AND COOL ADJACENT WATERS). GRADIENT SHOULD BE STRONGER FRIDAY...ENCOURAGING A STRONGER SOUTHERLY FLOW. MARINE... HAVE ISSUED A SCA FOR ALL WATERS THROUGH EARLY EVNG. EXPECT DECENT MIXING TODAY AND GUSTS NEAR 20 KT HAVE ALREADY BEGUN AT A FEW OF THE REPORTING STATIONS. THANKS AKQ FOR THE SCA COORD. AVIATION... BKN CIGS TODAY BUT SHOULD BARELY REMAIN IN THE VFR CATEGORY BETWEEN 3500-5000FT WITH AFTN CU DVLPT. DO NOT EXPECT ANY SIG FOG TNGT WITH COLD DPTS AND DRY GROUND. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY FOR ANZ530>537 UNTIL 6 PM SUNDAY. && $$ SHORT TERM/MARINE...PELOQUIN CLIMATOLOGY/AVIATION...GUYER PREV DISCUSSION...JB/ROGOWSKI md AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 315 PM CST SUN MAR 26 2006 .DISCUSSION...TONIGHT THROUGH WEDNESDAY PRIMARY CONCERN IN SHORT RANGE CONTINUES TO BE LOW PRESSURE SYSTEM PASSING NEARBY ON MONDAY AND ITS IMPACT ON PRECIPITATION TYPE AND TIMING. MORNING H5 ANALYSIS AND CURRENT GOES WV LOOP SHOWS SYSTEM OF INTEREST SPINNING ACROSS CENTRAL WY WITH UPGLIDING MOISTURE ENTERING THE UPPER MISSISSIPPI VALLEY. VIS LOOP SHOWS SOME ASSOCIATED MID-LEVEL CLOUDS OVER THE DAKOTAS BUT NO 88D RETURNS AT PRESENT. ATMOSPHERIC PROFILE OVER CWA NOT ALL THAT DRY AS SOME CU SEEN AND MORNING RAOBS INDICATED NO REAL DRY AIR INTRUSION AFTER THE LOW CLOUDS OF THE PAST FEW DAYS FINALLY ERODED. SO DO NOT THINK IT WILL TAKE LONG TO SATURATE TONIGHT AS MODEL PROGGED PWS ARE IN THE ORDER OF 0.5 TO 0.7 INCHES AND MIXING RATIOS ON LOW LEVEL THETA LAYERS OF CLOSE TO FOUR G/KG. HOWEVER FORCING IS LACKING DUE TO SYSTEM BEING STACKED AND DWINDLING WITH EACH SUCCESSIVE MODEL SOLUTION. UPPER LEVEL JET REMAINS WELL SOUTH WITH LEFT EXIT DIFFLUENT REGION AND ASSOCIATED H8-H5 OMEGA PEAKING OVER IA AND FAR SOUTHERN CWA. MODELS GENERALLY IN GOOD AGREEMENT AS 12Z AND 18Z NAM SOLUTIONS COMING IN LINE WITH THE GFS IN HAVING THE SYSTEM GLIDE ESE OVER IA. SOME WIDE HPC SREF SPREADS IN QPF LOCATION AND AMOUNT...BUT GENERALLY WENT WITH LIGHTER AMOUNTS AND LATER ONSET TIME DUE TO NO REAL AREA OF FOCUS. BUFKIT SNDGS ON THE VARIOUS MODELS INDICATE RA OR SN POSSIBILITIES. IN FAR WEST WHERE RUC AND NAM INDICATE OVERNIGHT LLJ OF 50KT...A PROGGED WARM LAYER OF 2-3C IS ADVECTED IN. SREF DOMINANT PRECIP TYPE DOES INDICATE SOME ZR WITH THIS...SO THEREFORE HAVE INTRODUCED THE CHC FROM 8Z THROUGH DAWN IN W AND NW ZONES. PRECIP CHANCES LAST ALL OF MONDAY AND INTO MONDAY NIGHT AS SYSTEM PROGGED TO MOVE SLOWLY...WITH BEST CHANCES GENERALLY IN SOUTHERN HALF OF CWA AND BEFORE 18Z MON. AFTER THAT POINT ASSOCIATED INVERTED SFC TROUGH PASSES AND DRIER AIR STARTS TO MOVE IN. PRECIP TYPE COULD SWITCH AROUND A FEW TIMES DURING THE DURATION OF THIS EVENT DUE TO DIABATIC EFFECTS AND DIURNAL TRENDS...BUT ALL IN ALL PRECIP SHOULD BE LIGHT AND GENERALLY RAIN OR SNOW WITH MAX SNOW ACCUMULATIONS AT AN INCH. LOW LEVEL CLOUDS SHOULD STICK AROUND FOR A WHILE SIMILAR TO LAST SYSTEM. LAZY LOW LEVEL FLOW SHOULD KEEP THEM THROUGH TUES AND POSSIBILY EVEN INTO TUES NIGHT. STRONG WAA STARTS IN ON WEDS AHEAD OF NEXT SYSTEM. WITH TEMPS DURING SHORT RANGE MADE ONLY MINOR TWEAKS...EDGING UP TEMPS A BIT THROUGH MON NIGHT GIVEN MAXS THIS AFTN. LONGER TERM...WEDNESDAY NIGHT THROUGH SUNDAY NIGHT THE LATEST ENSEMBLE MEMBERS OFF THE GFS AND EUROPEAN MODELS ARE SHOWING SIGNS OF DISCONTINUITY IN OVERALL UPPER AIR PATTERN OVER NORTH AMERICA DURING THE PERIOD...AS THE PATTERN BECOMES MORE PROGRESSIVE. GFS IS THE MORE AGGRESSOR OF LIFTING SYSTEM INTO THE GREAT LAKES BY SATURDAY MORNING. TIMING OF THE NEXT SYSTEM WILL BE CRITICAL THU AND FRI WITH THE LONGWAVE TROUGH AND SURFACE LOW PROJECTED TO MOVE INTO THE CENTRAL PLAINS ON THURSDAY. POPS STILL SEEM REASONABLE FOR THURSDAY AND FRIDAY DUE TO DYNAMICS ALONG WITH INCREASING INSTABLITY AHEAD OF THE SYSTEM. HOWEVER...THE BEST FORCING AND LIFT IS EXPECTED TO OCCUR OVER THE SOUTHERN HALF OF OUR FORECAST AREA. TEMPS BY THURSDAY ARE EXPECTED TO MODERATE INTO THE 50S THEN MORE TYPICAL SPRING-LIKE OVER THE UPCOMING WEEKEND. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ MTF/JVM mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 836 PM MST SUN MAR 26 2006 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH TUESDAY... UPDATES MADE TO END PRECIPITATION SOONER THIS EVENING...REDUCE SKY COVER...AND ADJUST WINDS. SHORT WAVE TROUGH CROSSING EASTERN WYOMING AND EASTERN MONTANA HAS MADE SLIGHTLY QUICKER PROGRESSION THAN EXPECTED...ENDING PRECIPITATION ACROSS WESTERN HALF OF CWA WITH PARTIAL CLEARING SPREADING INTO EXTREME WESTERN ZONES AS A FLAT SHORT WAVE RIDGE BUILDS INTO CENTRAL MONTANA. AREA RADARS SHOWING REDUCED REFLECTIVITIES OF PRECIPITATION BAND ACROSS EASTERN PORTION OF CWA...WITH FEW AUTOMATED STATIONS REPORTING PRECIP... SUGGESTING THAT PRECIPITATION WILL DWINDLE AS IT TRANSLATES TOWARD WESTERN DAKOTAS. MODELS SHOW ANOTHER SURGE OF MOISTURE INTO SHORT WAVE TROUGH AFTER MIDNIGHT...BUT CURRENT INDICATIONS ARE THIS WILL AFFECT DAKOTAS BECAUSE OF QUICKER PROGRESSION OF WHOLE SYSTEM. HENCE...HAVE DROPPED BACK TO NEAR ZERO POPS AFTER MIDNIGHT EXCEPT FOR AT MONTANA/DAKOTA BORDER. ALSO BRING CLEARING INTO WESTERN HALF OF CWA AFTER MIDNIGHT...AND TWEAKED 12-18Z GRID TO REDUCE SKY COVER EARLY IN SECOND PERIOD. NORTHWEST WINDS REMAIN QUITE FRESH BUT NOT CURRENTLY AS STRONG AS FORECAST...SO HAVE TWEAKED WINDS DOWN SLIGHTLY AND LIMITED GUSTS TO SOUTHEAST CORNER OF CWA. TEMPERATURES AND HUMIDITY APPEAR ON TRACK...IN PART BECAUSE OF PERSISTENCE OF WIND TO AFFORD SOME MIXING OVERNIGHT. SAME REASONING FOR NO MENTION OF FOG OVERNIGHT...EXPECT WIND TO KEEP THINGS MIXED. PREVIOUS SHORT TERM... UPPER LOW CLOSES OFF OVER NEBRASKA TONIGHT AND HEADS FURTHER EAST. LOCAL AREA WILL REMAIN UNDER THE UPPER TROUGH THIS EVENING. WITH DESCENT LIFT WILL SEE CONTINUED PRECIPITATION OVER THE EASTERN ZONES TONIGHT. SNOW/RAIN MIX WILL CHANGE OVER TO ALL SNOW LATE BUT AS THE AREA OF HEAVIEST PRECIPITATION MOVES INTO THE DAKOTAS THE LOCAL AREA WILL SEE DIMINISHING SNOWFALL OVERNIGHT. AN UPPER RIDGE WILL BEGIN BUILDING INTO THE REGION MONDAY AND SHOULD KEEP THE REMAINDER OF THE SHORT TERM DRY. TONIGHT...AS THE PRECIPITATION MOVES EAST THE 850MB TEMPERATURES ABOVE WILL REMAIN BELOW FREEZING...AROUND MINUS 2-3C SO WILL CONTINUE THE MIX INITIALLY AND TURN IT TO ALL SNOW AFTER 3Z AS SURFACE TEMPERATURES DROP. RUC PRETTY MUCH CUTS OFF MOST PRECIPITATION AFTER 3Z...ABOUT THE TIME THAT IT SHOULD TURN TO ALL SNOW. HOWEVER WILL LEAVE LIKELY POPS IN FOR THIS EVENING ACROSS THE EASTERN HALF OF THE CWA...THEN ONLY IN THE EASTERN ZONES AFTER MIDNIGHT. WITH PRETTY GOOD LIFT...USING A BLEND OF GFS AND NAM...COULD GET 1 TO 2 INCHES OF SNOW TONIGHT IN THE EASTERN ZONES. MONDAY AND MONDAY NIGHT...SKIES WILL BECOME PARTLY CLOUDY THEN CLEAR FROM THE WEST IN THE AFTERNOON. WITH TEMPERATURES RISING TO ABOVE NORMAL WITH MODERATE WEST WINDS...MONDAY COULD BECOME A PLEASANT DAY. HOWEVER OVERNIGHT WINDS WILL TURN TO THE SOUTHEAST ONCE AGAIN BUT AT MODERATE STRENGTH. TUESDAY...UPPER FLOW WILL SHIFT TO THE SOUTHWEST WHICH WILL INCREASE 850 TEMPERATURES TO 5C TO 10C. COULD BE THE WARMEST DAY OF THE WEEK. ALSO COULD SEE INCREASING HIGH CLOUD BY LATE AFTERNOON AS THE NEXT STORM SYSTEM MOVES ON SHORE ALONG THE PACIFIC COAST. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY... OTHER THAN A COUPLE OF MINOR TWEAKS TO RH AND DEWPOINT GRIDS...GOING FORECAST LOOKED GOOD. -TFJ PREVIOUS DISCUSSION... GOOD INITIAL AGREEMENT AMONG CANADIAN/ECMWF/GFS SOLUTIONS... BRINGING A LONG WAVE TROUGH INTO WESTERN CONUS TUESDAY NIGHT. AS TROUGH SWINGS EASTWARD INTO GREAT BASIN WEDNESDAY...INCREASING CHANCES OF RAIN SHOWERS SPREADING EASTWARD ACROSS REGION AS A SURFACE LOW TRACKS EAST ACROSS SOUTHERN MONTANA. GFS 850MB TEMPERATURES PROGGED TO REMAIN ABOVE FREEZING...AND TIMING DURING DAYLIGHT HOURS SUPPORTS LIQUID VERSUS FROZEN PHASE. WEDNESDAY NIGHT...EXPECT A MIX OF RAIN AND SNOW AS SURFACE TEMPERATURES LIKELY TO FALL A BIT BELOW FREEZING AND 850MB TEMPERATURES SAG TO AROUND FREEZING BY DAWN THURSDAY. BY DAY THURSDAY...LONG WAVE TROUGH SHIFTS EAST OF REGION AND DAMPS OUT...BRINGING AN END TO RAIN AND SNOW SHOWERS FROM WEST ACROSS CWA. SLIGHTLY COOLER AIRMASS BUILDS INTO REGION ON VEERING UPPER FLOW BY THURSDAY NIGHT WITH PARTIAL CLEARING. BEGINNING FRIDAY...MODEL SOLUTIONS DIVERGE MORE SIGNIFICANTLY AS GFS DEVELOPS A QUASI-ZONAL FLOW PATTERN FOR NORTHERN PLAINS THROUGH REMAINDER OF PERIOD...WHILE ECMWF BRINGS ANOTHER LONG WAVE TROUGH INTO WESTERN CONUS SIMILAR TO SYSTEM EXPECTED MID-WEEK. HAVE CHOSEN TO KEEP THIS LATER PERIOD DRY WITH NEAR SEASONABLE TEMPERATURES DUE TO ZONAL FLOW IN GFS...AND ECMWF APPEARS TO TAKE BULK OF MOISTURE AND JET DYNAMICS SOUTH OF REGION. THIS APPROACH SEEMS REASONABLE FOR FRIDAY...BUT SATURDAY MORE UNCERTAIN. && .AVIATION... A MIX OF RAIN AND SNOW IS DIMINISHING AS IT EXITS EASTERN MONTANA THIS EVENING. THE PRECIP SHOULD COMPLETELY EXIT THE STATE BY 06Z. LOW CLOUDS WILL GRADUALLY CLEAR OVERNIGHT FROM WEST TO EAST. SKIES SHOULD REMAIN MOSTLY CLEAR ON MONDAY. MVFR CONDITIONS AT KGDV AND KSDY SHOULD IMPROVE TO VFR BY 06Z. OTHERWISE...LOOK FOR VFR CONDITIONS THROUGH MONDAY. GFF && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW mt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 216 PM MST SUN MAR 26 2006 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH TUESDAY... UPPER LOW CLOSES OFF OVER NEBRASKA TONIGHT AND HEADS FURTHER EAST. LOCAL AREA WILL REMAIN UNDER THE UPPER TROUGH THIS EVENING. WITH DESCENT LIFT WILL SEE CONTINUED PRECIPITATION OVER THE EASTERN ZONES TONIGHT. SNOW/RAIN MIX WILL CHANGE OVER TO ALL SNOW LATE BUT AS THE AREA OF HEAVIEST PRECIPITATION MOVES INTO THE DAKOTAS THE LOCAL AREA WILL SEE DIMINISHING SNOWFALL OVERNIGHT. AN UPPER RIDGE WILL BEGIN BUILDING INTO THE REGION MONDAY AND SHOULD KEEP THE REMAINDER OF THE SHORT TERM DRY. TONIGHT...AS THE PRECIPITATION MOVES EAST THE 850MB TEMPERATURES ABOVE WILL REMAIN BELOW FREEZING...AROUND MINUS 2-3C SO WILL CONTINUE THE MIX INITIALLY AND TURN IT TO ALL SNOW BY 3Z AS SURFACE TEMPERATURES DROP. RUC PRETTY MUCH CUTS OFF MOST PRECIPITATION AFTER 3Z...ABOUT THE TIME THAT IT SHOULD TURN TO ALL SNOW. HOWEVER WILL LEAVE LIKELY POPS IN FOR THIS EVENING ACROSS THE EASTERN HALF OF THE CWA...THEN ONLY IN THE EASTERN ZONES AFTER MIDNIGHT. WITH PRETTY GOOD LIFT...USING A BLEND OF GFS AND NAM...COULD GET 1 TO 2 INCHES OF SNOW TONIGHT IN THE EASTERN ZONES. MONDAY AND MONDAY NIGHT...SKIES WILL BECOME PARTLY CLOUDY THEN CLEAR FROM THE WEST IN THE AFTERNOON. WITH TEMPERATURES RISING TO ABOVE NORMAL WITH MODERATE WEST WINDS...MONDAY COULD BECOME A PLEASANT DAY. HOWEVER OVERNIGHT WINDS WILL TURN TO THE SOUTHEAST ONCE AGAIN BUT AT MODERATE STRENGTH. TUESDAY...UPPER FLOW WILL SHIFT TO THE SOUTHWEST WHICH WILL INCREASE 850 TEMPERATURES TO 5C TO 10C. COULD BE THE WARMEST DAY OF THE WEEK. ALSO COULD SEE INCREASING HIGH CLOUDS BY LATE AFTERNOON AS THE NEXT STORM SYSTEM MOVES ON SHORE ALONG THE PACIFIC COAST. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY... OTHER THAN A COUPLE OF MINOR TWEAKS TO RH AND DEWPOINT GRIDS...GOING FORECAST LOOKED GOOD. -TFJ PREVIOUS DISCUSSION... GOOD INITIAL AGREEMENT AMONG CANADIAN/ECMWF/GFS SOLUTIONS... BRINGING A LONG WAVE TROUGH INTO WESTERN CONUS TUESDAY NIGHT. AS TROUGH SWINGS EASTWARD INTO GREAT BASIN WEDNESDAY...INCREASING CHANCES OF RAIN SHOWERS SPREADING EASTWARD ACROSS REGION AS A SURFACE LOW TRACKS EAST ACROSS SOUTHERN MONTANA. GFS 850MB TEMPERATURES PROGGED TO REMAIN ABOVE FREEZING...AND TIMING DURING DAYLIGHT HOURS SUPPORTS LIQUID VERSUS FROZEN PHASE. WEDNESDAY NIGHT...EXPECT A MIX OF RAIN AND SNOW AS SURFACE TEMPERATURES LIKELY TO FALL A BIT BELOW FREEZING AND 850MB TEMPERATURES SAG TO AROUND FREEZING BY DAWN THURSDAY. BY DAY THURSDAY...LONG WAVE TROUGH SHIFTS EAST OF REGION AND DAMPS OUT...BRINGING AN END TO RAIN AND SNOW SHOWERS FROM WEST ACROSS CWA. SLIGHTLY COOLER AIRMASS BUILDS INTO REGION ON VEERING UPPER FLOW BY THURSDAY NIGHT WITH PARTIAL CLEARING. BEGINNING FRIDAY...MODEL SOLUTIONS DIVERGE MORE SIGNIFICANTLY AS GFS DEVELOPS A QUASI-ZONAL FLOW PATTERN FOR NORTHERN PLAINS THROUGH REMAINDER OF PERIOD...WHILE ECMWF BRINGS ANOTHER LONG WAVE TROUGH INTO WESTERN CONUS SIMILAR TO SYSTEM EXPECTED MID-WEEK. HAVE CHOSEN TO KEEP THIS LATER PERIOD DRY WITH NEAR SEASONABLE TEMPERATURES DUE TO ZONAL FLOW IN GFS...AND ECMWF APPEARS TO TAKE BULK OF MOISTURE AND JET DYNAMICS SOUTH OF REGION. THIS APPROACH SEEMS REASONABLE FOR FRIDAY...BUT SATURDAY MORE UNCERTAIN. && .AVIATION... LOW CEILINGS SHOULD CONTINUE TO HAMPER THE TERMINAL SITES THROUGH THE EVENING HOURS. A NARROW PRECIPITATION BAND OF MOSTLY SNOW (SOME RAIN MIXED IN LATE THIS AFTERNOON) WILL DIMINISH BY EARLY EVENING FROM WEST TO EAST. MVFR CEILINGS ARE EXPECTED TO DISIPATE FROM WEST TO EAST LATE (BY MORNING AT KSDY AND KGDV). A SURFACE TROUGH MOVING EAST SHOULD SWING SURFACE WINDS TO THE NORTHWEST AT KOLF THEN KSDY BY EARLY THIS EVENING. VFR CONDITIONS ARE EXPECTED LATER TONIGHT AND MONDAY WITH NORTHWEST WINDS ALL SITES. -TFJ && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW mt AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE GLASGOW MT 921 AM MST SUN MAR 26 2006 .SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH TUESDAY... UPDATE...PRECIPITATION IS CUTTING ACROSS THE SOUTHWEST CORNER OF THE CWA BUT THE BULK REMAINS TO THE WEST OF THE FORECAST AREA. THE RUC/GFS AND NAM ALL SHOW SIGNIFICANT QPF MOVING INTO THE AREA BY AFTERNOON. TEMPERATURES ALOFT REMAIN BELOW 0C FOR MOST OF THE CWA BUT SURFACE TEMPERATURES ARE RISING INTO THE MID 40S F TO THE SOUTHWEST AND MID 30S ELSEWHERE. GENERALLY KEPT PRECIPITATION AS A RAIN/SNOW MIX. SNOW AMOUNTS COULD RANGE AROUND 1 OR 2 INCHES THROUGH THIS EVENING. ALSO ADJUSTED MAX TEMPS AND WINDS TO FIT CURRENT OBSERVATIONS AND UPDATED MODELS. SCT PREVIOUS DISCUSSION... SURFACE TROF NEARING THE WESTERN FRINGE OF THE CWA CURRENTLY. EAST WIND STILL GOING STRONG ACROSS THE AREA. THIS SURFACE TROF WILL MOVE STEADILY EAST ACROSS THE AREA TODAY BRINGING A WIND SHIFT TO NORTHWEST. OTHER THAN ALONG THE TROF AXIS AS IT PASSES THERE WILL BE NO RESPITE FROM THE WIND AS IT WILL BLOW STRONGER BEHIND THE TROF THIS AFTERNOON AND EVENING BEFORE ABATING OVERNIGHT. THE UPPER TROF WILL FOLLOW CLOSELY BEHIND THE SURFACE TROF WITH THE LIONS SHARE OF THE ENERGY PASSING SOUTH OF US ACROSS WYOMING INTO SOUTHERN MONTANA. GOOD MOISTURE ACROSS THE AREA ALREADY SO AS WE GET BETTER DYNAMICS TODAY WITH THE PASSAGE OF THE SYSTEM WE SHOULD SEE MOST OF THE AREA GETTING AT LEAST SOME PRECIPITATION. THERMAL PROFILES STILL PRETTY MUCH A MESS...SO STILL DIFFICULT TO PUT A FINGER ON EXACTLY WHEN AND WHO GETS WHAT. THAT SAID...WILL REMOVE MENTION OF FREEZING RAIN AS MOST SPOTS ACROSS THE AREA STILL ABOVE FREEZING WITH CLOUDS LOWERING AND DEWPOINTS RISING. SO NOT REALLY EXPECTING TEMPERATURES TO DROP MUCH...IF ANY FROM WHERE THEY ARE NOW. PRECIPITATION SHOWING UP ON RADAR STILL WELL WEST OF THE CWA. SO PROBABLY THE BULK OF THE PRECIPITATION WILL NOT ARRIVE UNTIL AFTER SUNRISE AND TEMPERATURES GET A CHANCE TO RISE A BIT. WITH THE MODELS NOT EVEN CLOSE TO BEING ON THE SAME PAGE WITH RESPECT TO THERMAL PROFILES TODAY...WILL LEAVE THE PRECIPITATION TODAY AS RAIN OR SNOW...EVEN THO MOST SPOTS SHOULD EXPERIENCE TEMPERATURES TODAY AT LEAST SLIGHTLY ABOVE FREEZING. WILL LEAVE PRECIPITATION ALL SNOW TONIGHT AS IT MARCHES EAST AND OUT OF HERE BY MONDAY MORNING AS THE MODELS DO COME TOGETHER A BIT BETTER FOR TONIGHT WITH EXPECTED TEMPERATURES ALOFT. SNOW AMOUNTS SHOULD BE ON THE LIGHT SIDE WITH PERHAPS NEAR 2 INCHES IN THE SOUTHEAST PORTION OF THE CWA WHERE BEST LIFT SHOULD OCCUR. HIGH PRESSURE MOVES IN AT ALL LEVELS BY MONDAY AFTERNOON. UPPER RIDGE REMAINS IN PLACE FOR TUESDAY BUT THE SURFACE HIGH DRIFTS EAST AND LOW PRESSURE HEADS OUR WAY FROM THE WEST. THIS SETS UP...YES YOU GUESSED IT...ANOTHER ROUND OF EAST WIND. AT LEAST 850MB THERMAL RIDGE HEADS OUR WAY IN ADVANCE OF THE LOW PRESSURE ALLOWING FOR A WARMUP. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY... GOOD INITIAL AGREEMENT AMONG CANADIAN/ECMWF/GFS SOLUTIONS...BRINGING A LONG WAVE TROUGH INTO WESTERN CONUS TUESDAY NIGHT. AS TROUGH SWINGS EASTWARD INTO GREAT BASIN WEDNESDAY...INCREASING CHANCES OF RAIN SHOWERS SPREADING EASTWARD ACROSS REGION AS A SURFACE LOW TRACKS EAST ACROSS SOUTHERN MONTANA. GFS 850MB TEMPERATURES PROGGED TO REMAIN ABOVE FREEZING...AND TIMING DURING DAYLIGHT HOURS SUPPORTS LIQUID VERSUS FROZEN PHASE. WEDNESDAY NIGHT...EXPECT A MIX OF RAIN AND SNOW AS SURFACE TEMPERATURES LIKELY TO FALL A BIT BELOW FREEZING AND 850MB TEMPERATURES SAG TO AROUND FREEZING BY DAWN THURSDAY. BY DAY THURSDAY...LONG WAVE TROUGH SHIFTS EAST OF REGION AND DAMPS OUT...BRINGING AN END TO RAIN AND SNOW SHOWERS FROM WEST ACROSS CWA. SLIGHTLY COOLER AIRMASS BUILDS INTO REGION ON VEERING UPPER FLOW BY THURSDAY NIGHT WITH PARTIAL CLEARING. BEGINNING FRIDAY...MODEL SOLUTIONS DIVERGE MORE SIGNIFICANTLY AS GFS DEVELOPS A QUASI-ZONAL FLOW PATTERN FOR NORTHERN PLAINS THROUGH REMAINDER OF PERIOD...WHILE ECMWF BRINGS ANOTHER LONG WAVE TROUGH INTO WESTERN CONUS SIMILAR TO SYSTEM EXPECTED MID-WEEK. HAVE CHOSEN TO KEEP THIS LATER PERIOD DRY WITH NEAR SEASONABLE TEMPERATURES DUE TO ZONAL FLOW IN GFS...AND ECMWF APPEARS TO TAKE BULK OF MOISTURE AND JET DYNAMICS SOUTH OF REGION. THIS APPROACH SEEMS REASONABLE FOR FRIDAY...BUT SATURDAY MORE UNCERTAIN. && .AVIATION... UPDATED AT 1620Z. LOW LEVEL CLOUDS HAVE OVERSPREAD ENTIRE AREA AS A STORM SYSTEM PUSHES IN FROM THE WEST. MOST CEILINGS HAVE GONE TO MVFR...TO AROUND 2K FT AGL. SNOW WITH SOME MIX WITH RAIN WILL SPREAD FRO WEST TO EAST WITH THE STORM TODAY. PRECIPITATION WILL END WEST DURING EVENING BUT LINGER THROUGH MIDNIGHT OVER THE EAST. WITH FALLING TEMPERATURES DURING EVENING....WILL SEE ANY RAIN/SNOW MIX CHANGE TO SNOW AS PRECIPITATION ENDS. CURRENT EAST WINDS WILL SWITCH TO NORTHWEST DURING THE AFTERNOON OVER NE MT AS THE CENTER OF LOW PRESSURE MOVES SOUTHEAST OF CWA. PARTIAL CLEARING WILL REACH WESTERN PORTIONS OF THE TWEB ROUTE/TERMINALS OVERNIGHT...BUT LOW CEILINGS EXPECTED TO LINGER OVER EASTERN PORTION OF TWEB ROUTE/TERMINALS. && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW mt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 1133 AM EST SUN MAR 26 2006 .SHORT TERM /REST OF TODAY/... SAT IMAGERY SHOWS CLOUD COVER QUITE EXTENSIVE ON BACK SIDE OF UPR LOW CIRC AS UPR LOW CENTER LIFTS EAST OF PA. CLOUDS WILL KEEP TEMPS FROM INCREASING TOO MUCH THIS AFTN...BUT CURRENT TEMP READINGS AND A LITTLE RISE FIT WELL WITH CURRENT FCST MAXES. REMOVED ANY SIG POPS EXCEPT ACROSS FAR NRWN MTNS WHERE SOME LAKE ENHANCED SHOWERS MAY DEVELOP THIS AFTN. NO CHANGES BEYOND FIRST PD. && .PREV DISCUSSION... /ISSUED 238 AM EST SUN MAR 26 2006/ SHORT TERM /TODAY THROUGH TUESDAY/... SATELLITE IMAGERY SHOWING UPPER LO PUSHING EAST OVR CHESAPEAKE BAY EARLY THIS MORNING. WK S/WV HAS PRODUCED SCT -SHSN OVR SW PA EARLIER TONIGHT. HOWEVER...THIS DISTURBANCE IS NOW EXITING SOUTHERN PA AND SHOULD BE CLEAR OF THE REGION BY DAWN. BEST CHC OF PRECIP TODAY SHOULD BE ACROSS SE PA...CLOSEST TO DEPARTING UPPER LOW. A LGT RAIN/SNOW MIX CURRENTLY FALLING OVER EASTERN PA...AND LATEST RUC/NAM DATA SUGGESTS THIS AREA OF PRECIP BRUSHES OUR SE ZONES THRU EARLY AFTN. BRKS IN CLOUD COVER OVR CENTRAL PA EARLY THIS AM WILL FILL IN BY LATE AM AS SUN GOES TO WORK. MODEL 850 TEMPS SUGGEST SIMILAR HIGHS TO YESTERDAY. EXPECT CRUMBLING CU THIS EVENING WITH LOSS OF HEATING AND APPROACH OF HI PRES RIDGE. HAVE LOWERED SKY GRIDS CONSIDERABLY...MAKING MOST SPOTS CLEAR BY LATE EVENING. MONDAY LOOKS NEARLY CLOUDLESS UNDER INFLUENCE OF HI PRES AT SFC AND ALOFT. 850 TEMPS ARND -2C SHOULD SUPPORT HIGHS U40S MTNS...TO M50S SUSQ VALLEY. CALM WIND AND CLEAR SKIES WILL ALLOW TEMPS TO FALL QUICKLY MONDAY EVENING. HOWEVER...INCR CLDS AHEAD OF APPROACHING LO PRES MAY LIMIT COOLING. SREF DATA TRACKING WK SFC LO OVR SOUTHERN PA ON TUESDAY. ENSEMBLE QPF DATA SUGGESTS BEST CHC FOR -RA OVR SOUTHERN AND WESTERN PA. LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... LATEST MREF DATA SUGGESTS DRY WX THURS/FRI WITH A WARMING TREND...AS UPPER LVL RIDGE BUILDS OVR THE EAST COAST. A COLD FRONT LATE FRI OR SAT WILL LIKELY BE ACCOMPANIED BY A ROUND OF SHRA. AVIATION... AS WAS THE CASE LAST NIGHT...MUCH OF CENTRAL PA IS CLR WITH VFR CONDITIONS. LIKE LAST NIGHT..EXPECT PATCHY FOG AROUND SUNRISE FOR A FEW HOURS. OTHERWISE...MUCH OF THE AREA WILL HAVE VFR CONDITIONS TODAY. SOME IFR AND MVFR CONDITIONS AT THE CURRENT TIME ACROSS WESTERN AREAS...WITH A WIDE RANGE IN CONDITIONS. EXPECT THESE AREAS TO HAVE VFR CONDITIONS BY LATE MORNING...AS THE AIRMASS IS QUITE DRY...AND THE UPPER LEVEL LOW MOVES AWAY FROM THE AREA. WINDS WILL BE ON THE BRISK SIDE THIS AFT. WINDS WILL WEAKEN SOME OVERNIGHT...BUT EXPECT MORE WIND THAN THE LAST 2 NIGHTS...SO MOST AREAS SHOULD HAVE VFR CONDITIONS...AS FOG SHOULD BE LESS OF A PROBLEM. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GARTNER pa AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ABERDEEN SD 1140 AM CST SUN MAR 26 2006 TEMPS ACROSS THE EAST HAVE SHOT UP UNDER MOSUNNY SKIES...PROMPTING AN INCREASE IN MAX T GRIDS THERE. LATEST HI-RES NAM AND GFS ARE IN AGREEMENT ON MOVT OF UPPER LOW AND SFC LOW INTO THE REGION LATER THIS AFTN AND TONIGHT. NAM BUFKIT AND HI-RES NAM SOLNS ALL SHOW PCPN HOLDING OFF UNTIL LATE THIS AFTN AND INTO THE EVENING. HAVE TWEAKED PCPN GRIDS FOR A LATER STARTING TIME TO THE PCPN. WINDS CONT TO BUMP UP AGAINST WIND ADVRY CRITERIA FOR MANY AREAS...BUT AFTER INITIAL HOUR OF THAT THEY SEEM TO BE SETTLING BACK DOWN...SO NO HEADLINE FOR WINDS NEEDED ATTM. ...PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH TUESDAY NIGHT UPPER LEVEL RIDGE AXIS CENTERED OVER DAKOTAS EARLY THIS MORNING WHILE APPROACHING STORM SYSTEM IS MOVING EAST ACROSS THE ROCKIES. SFC PRESSURE GRADIENT TIGHTENING BETWEEN HIGH OVER MN/WI AND LOW OVER ROCKIES. SE WINDS ALREADY 15-25 MPH FROM JAMES RIVER WEST AND WILL INCREASE THROUGHOUT THE DAY. LOW CLOUDS STREAMING NORTH INTO CWA WITH MOISTURE AND WARM AIR ADVECTION. REMOVED FRZ DRIZZLE MENTION FOR THE EARLY MORNING HOURS AS CEILINGS APPEAR TO BE A BIT TOO HIGH AND TEMP/DEWPOINT SPREADS REMAIN AROUND 5 DEGREES. CEILING/VIS OBS ACROSS NEB PANHANDLE INDICATE CEILINGS BELOW 1000 FT WITH VIS DROPPING TO AROUND 5-6SM. BELIEVE ANY DRIZZLE THAT'S OCCURRING WOULD BE ACROSS THIS AREA. FIRST PART OF TODAY WILL FEATURE INCREASING SE WINDS...ALONG WITH CLOUDY TO MOSTLY CLOUDY SKIES. HELD BACK ON PRECIP CHANCES ACROSS CENTRAL SD UNTIL THE AFTERNOON HOURS AS BEST LIFT ASSOCIATED WITH WAVE DOES NOT OCCUR UNTIL THEN. MODELS ARE SHOWING SFC LOW TRACKING ACROSS SD WITH SFC LOW CENTER NEAR MN BORDER BY 12Z MON. THERE ARE SLIGHT VARIATIONS IN EXACT TRACK...WITH GFS AND UK A BIT FARTHER SOUTH TOWARDS I-90 AND SD/NE BORDER WHILE RUC AND NGM CLOSER TO NORTHERN TIER OF COUNTIES. NAM FOLLOWS MORE OF A GFS TRACK. STILL APPEARS AS IF BEST CHANCE FOR RAIN WILL BE ACROSS THE EASTERN COUNTIES BETWEEN 00Z AND 12Z TONIGHT ASSOCIATED WITH THE BEST 850-700MB OMEGA...ISENTROPIC FEATURES...AND UPPER DIVERGENCE. RAISED POPS TO LIKELY ACROSS THE EAST OVERNIGHT. ONE OF THE MORE DIFFICULT AREAS WITH THIS SYSTEM IS DECIDING HOW MUCH COLD AIR WILL GET WRAPPED INTO THE AREA ON MON MORNING. HAVE KEPT ALL RAIN MENTION FOR THE MOST PART IN THE EAST BUT THERE SHOULD BE A RAIN/SNOW MIX AROUND AND JUST AFTER SUNRISE ON MON ACROSS THE CENTRAL BEFORE TEMPS CLIMB ENOUGH TO CHANGE BACK TO RAIN. FEEL THAT THERE WILL BE A DECENT AMOUNT OF WARM AIR DRAWN INTO THE SYSTEM AND WITH CLOUDS TONIGHT AND BREEZY WINDS...THINK THAT TEMPERATURES WILL HAVE A TOUGH TIME FALLING. SYSTEM DEPARTS MON EVENING MAKING WAY FOR HIGH PRESSURE ON TUE. SHOULD SEE FAIRLY MILD TEMPS THIS DAY WITH GOOD AMOUNTS OF SUNSHINE EXPECTED. TEMPS SHOULD REBOUND TO NEAR NORMAL...WITH HIGHS IN THE MID 40S TO LOW 50S. RIDGE AXIS WILL MOVE EAST BY TUESDAY EVENING AS SE SFC FLOW RETURNS IN ADVANCE OF YET ANOTHER APPROACHING SYSTEM. .LONG TERM...WEDNESDAY THROUGH SATURDAY. IN THE LONG TERM...TEMPERATURES WARM UP FOR WEDNESDAY...WITH MODELS FORECASTING AROUND 5 TO 10 C AIR AT 850 MB. SNOW COVER OVER THE SOUTHWEST HOPEFULLY WILL BE LIMITED BY THIS TIME...BUT HAVE KEPT TEMPS A LITTLE COOLER THAN POSSIBLE FOR NOW. LOW LEVEL JET INCREASES WEDNESDAY NIGHT...AND WITH SOME WEAK ELEVATED INSTABILITY...WENT WITH SHOWERS AND THUNDERSTORMS. MODELS IN GOOD AGREEMENT BRINGING UPPER TROUGH AND SURFACE LOW INTO THE NORTHERN PLAINS WEDNESDAY NIGHT. TIMING AND TRACK DIFFERENCES DO EXIST HOWEVER. THE 00Z GFS IS QUICKER AND MORE TO THE SOUTH VERSUS THE 18Z RUN. THE 00Z ECMWF IS SLOWER LIKE THE 18Z GFS...AND HAS A MORE OPEN TROUGH...WHILE THE 00Z CANADIAN IS QUICKER LIKE THE 00Z GFS. THE 18Z GFS ENSEMBLE MEAN WAS A COMPROMISE...BUT CLOSER TO THE SLOWER SOLUTION. THIS PUTS THE LOW NEAR THE ND/SD BORDER BY 00Z FRI. HAVE GONE WITH A COMPROMISE SOLUTION AT THIS TIME. GFS INDICATES THAT A DRY PUNCH MIGHT PUSH INTO THE AREA AHEAD OF THE MID/UPPER LEVEL LOW ON THURSDAY. LIMITED POPS TO 40 FOR UNCERTAINTY REGARDING THE TIMING OF THE DRIER AIR. INSTABILITY WILL STILL BE IN THE EAST THROUGH THE DAY ON THURSDAY...CONTINUED WITH THUNDER MENTION. TROWAL ON THE BACK SIDE OF LOW WILL HELP KEEP PRECIPITATION CHANCES IN THE AREA THROUGH THURSDAY NIGHT. SNOW WILL BE POSSIBLE THURSDAY NIGHT...BUT VERY CLOSE SO KEPT BOTH RAIN/SNOW IN FORECAST. LOW PUSHES OFF TO THE ENE ON FRIDAY...WITH WEAK HIGH PRESSURE SETTLING IN. AN UPPER LEVEL LOW WILL LIKELY PUSH ESE ACROSS SRN CANADA ON SATURDAY...POSSIBLY RESULTING IN A WEAK PUSH OF COOLER AIR LATE SATURDAY/SATURDAY NIGHT. KEPT CLOSER TO A WARMER/MORE SEASONAL SOLUTION FOR NOW...CLOSER TO THE 00Z GFS. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ DLH/TT/RK sd AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE FORT WORTH TX 1130 AM CST SUN MAR 26 2006 .UPDATE... HIGH CLOUDS WILL CONTINUE TO SPREAD EASTWARD ACROSS THE REGION THIS AFTERNOON. THE TIGHT PRESSURE GRADIENT DUE TO THE STRONG LEE SIDE TROUGH...IS RESULTING STRONG SOUTHERLY WINDS. THE WIND ADVISORY LOOKS GOOD FOR THE AREA ALONG AND WEST OF THE I-35 CORRIDOR. ONLY MINOR GRID CHANGES WERE MADE TO THE PREVIOUS FORECAST. UPDATES HAVE BEEN SENT. #58 && .AVIATION... 535 AM CST SUN MAR 26 2006 12Z FWD RAOB HAS MEASURED WINDS FROM 180 AT 30KT AT 1000 FT AND THIS WILL BE SUFFICIENT FOR THE INCLUSION OF LLWS THRU 15Z. SURFACE WINDS ARE LIGHT SE NOW...BUT STRONGER AND MORE SOUTHERLY WINDS WILL MIX TO THE SURFACE AFTER 15Z. LOW LEVEL MOISTURE BEGINNING TO RETURN NORTHWARD ACROSS SOUTH TEXAS NOW...AND MODELS INDICATING SOME AFTERNOON CUMULUS NEAR 050 FT WILL BE POSSIBLE. CIG NEAR 040-050 WILL DEVELOP/ADVECT FROM THE SOUTH AFTER SUNSET. ETA LOOKS A LITTLE TOO AGGRESSIVE WITH BOUNDARY LAYER MOISTURE AND HAVE SIDED WITH GFS/RUC FORECASTS. STRATUS WILL CONTINUE TO DEVELOP/LOWER TO MVFR CRITERIA AFTER MIDNIGHT AS STRONG LOW LEVEL JET SETS UP OVER N TX. TR/92 && .UPDATE... && .PREV DISCUSSION... 359 AM CST SUN MAR 26 2006 WIND ADVISORY NOW ISSUED FOR THOSE AREAS OF NORTH TEXAS GENERALLY ALONG AND WEST OF THE I-35 CORRIDOR. SEE ADVISORY LINE OR FTWNPWFWD FOR DETAILS. 342 AM CST SUN MAR 26 2006 UPPER RIDGE THAT HAS KEPT THINGS DRY AND COOL TO MILD THE PAST FEW DAYS WILL SLOWLY BREAK DOWN...AS STRONG S/W TROUGH MOVING THROUGH ROCKIES EJECTS INTO THE CENTRAL/NRN PLAINS THROUGH MONDAY. THE ENHANCED CYCLOGENESIS THAT OCCURS OVER THE WRN HIGH PLAINS WILL MAKE FOR A WINDY DAY AND MAY NEED A WIND ADVISORY FOR AT LEAST WRN/CENTRAL COUNTIES THIS AFTN AND WILL MAKE DECISION AT FCST ISSUANCE HERE SHORTLY. ON MONDAY...AS AFOREMENTIONED S/W MOVES OVER UPPER MIDWEST/MS VALLEY REGION. ISENTROPIC LIFT WILL ENSUE IN CRITICAL 850-700 MB LAYER AND SATURATE THINGS IN A HURRY OVER N TX BY MON EVE...AS COLD FRONT MOVES SWD INTO TX PANHANDLE/OK AND TOWARD RED RIVER BY 12Z TUES. A GOOD SWATH OF RAIN/THUNDERSTORMS...SOME WITH HEAVY RAIN (PWATS 1-1.5 INCHES) WILL ENCOMPASS A MAJORITY OF N TX WITH ALL FEATURES MENTIONED...WITH MODELS AND NCEP IN AGREEMENT WITH FRONT STALLING OR WAVERING ACROSS N TX NEAR OR SOUTH OF I-20 CORRIDOR THROUGH WED MORNING AS ACTIVE SPLIT UPPER FLOW OVER THE CENTRAL CONUS. INCREASED POPS AS SUCH TO CLOSE OR SLIGHTLY ABOVE MOS GUIDANCE. TEMPS WERE ALSO TRICKY AND DIDN'T TRY TO GET TOO CUTE...JUST IN VICINITY OF CONSENSUS MOS NUMBERS THROUGH MID WEEK WITH CONFIDENCE WAVERING ON EXTENT OF RAINFALL...FRONTAL POSITION...ETC DURING THIS TIME FRAME. NEXT UPPER TROUGH PUNCHES THROUGH THE WRN STATES AND INTO THE ROCKIES BY THURS INTO FRI. THIS WILL SHOOT OLD BOUNDARY NWD AS A WARM FRONT AND WANED POPS/WARMED MAX TEMPS WITH MORE PARTLY CLOUDY CONDITIONS. SYSTEM WILL EJECT WELL NWD AGAIN...BUT LOOKS LIKE A DRYLINE/POTENTIAL SEVERE WEATHER EVENT COULD OCCUR THURS AFTN INTO FRI MORNING IF ALL PANS OUT...BUT THIS IS STILL A WAYS OFF AND CONFIDENCE IS LOW WITH THIS SYSTEM AND PARAMETERS INTO NEXT WEEKEND. GENERALLY MADE LITTLE CHANGES THIS FAR OUT. && .FWD WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM 10 AM SUNDAY TO 6 PM SUNDAY FOR TXZ091-TXZ092- TXZ093-TXZ100-TXZ101-TXZ102-TXZ103-TXZ104-TXZ115-TXZ116-TXZ117- TXZ118-TXZ119-TXZ129-TXZ130-TXZ131-TXZ132-TXZ133-TXZ134-TXZ141- TXZ142-TXZ143-TXZ144-TXZ145-TXZ156-TXZ157-TXZ158-TXZ159. && $$ /05 tx AREA FORECAST DISCUSSION...UPDATED FOR AVIATION NATIONAL WEATHER SERVICE FORT WORTH TX 535 AM CST SUN MAR 26 2006 .AVIATION... 12Z FWD RAOB HAS MEASURED WINDS FROM 180 AT 30KT AT 1000 FT AND THIS WILL BE SUFFICIENT FOR THE INCLUSION OF LLWS THRU 15Z. SURFACE WINDS ARE LIGHT SE NOW...BUT STRONGER AND MORE SOUTHERLY WINDS WILL MIX TO THE SURFACE AFTER 15Z. LOW LEVEL MOISTURE BEGINNING TO RETURN NORTHWARD ACROSS SOUTH TEXAS NOW...AND MODELS INDICATING SOME AFTERNOON CUMULUS NEAR 050 FT WILL BE POSSIBLE. CIG NEAR 040-050 WILL DEVELOP/ADVECT FROM THE SOUTH AFTER SUNSET. ETA LOOKS A LITTLE TOO AGGRESSIVE WITH BOUNDARY LAYER MOISTURE AND HAVE SIDED WITH GFS/RUC FORECASTS. STRATUS WILL CONTINUE TO DEVELOP/LOWER TO MVFR CRITERIA AFTER MIDNIGHT AS STRONG LOW LEVEL JET SETS UP OVER N TX. TR/92 && .UPDATE... WIND ADVISORY NOW ISSUED FOR THOSE AREAS OF NORTH TEXAS GENERALLY ALONG AND WEST OF THE I-35 CORRIDOR. SEE ADVISORY LINE OR FTWNPWFWD FOR DETAILS. && .PREV DISCUSSION... /ISSUED 342 AM CST SUN MAR 26 2006/ DISCUSSION... UPPER RIDGE THAT HAS KEPT THINGS DRY AND COOL TO MILD THE PAST FEW DAYS WILL SLOWLY BREAK DOWN...AS STRONG S/W TROUGH MOVING THROUGH ROCKIES EJECTS INTO THE CENTRAL/NRN PLAINS THROUGH MONDAY. THE ENHANCED CYCLOGENESIS THAT OCCURS OVER THE WRN HIGH PLAINS WILL MAKE FOR A WINDY DAY AND MAY NEED A WIND ADVISORY FOR AT LEAST WRN/CENTRAL COUNTIES THIS AFTN AND WILL MAKE DECISION AT FCST ISSUANCE HERE SHORTLY. ON MONDAY...AS AFOREMENTIONED S/W MOVES OVER UPPER MIDWEST/MS VALLEY REGION. ISENTROPIC LIFT WILL ENSUE IN CRITICAL 850-700 MB LAYER AND SATURATE THINGS IN A HURRY OVER N TX BY MON EVE...AS COLD FRONT MOVES SWD INTO TX PANHANDLE/OK AND TOWARD RED RIVER BY 12Z TUES. A GOOD SWATH OF RAIN/THUNDERSTORMS...SOME WITH HEAVY RAIN (PWATS 1-1.5 INCHES) WILL ENCOMPASS A MAJORITY OF N TX WITH ALL FEATURES MENTIONED...WITH MODELS AND NCEP IN AGREEMENT WITH FRONT STALLING OR WAVERING ACROSS N TX NEAR OR SOUTH OF I-20 CORRIDOR THROUGH WED MORNING AS ACTIVE SPLIT UPPER FLOW OVER THE CENTRAL CONUS. INCREASED POPS AS SUCH TO CLOSE OR SLIGHTLY ABOVE MOS GUIDANCE. TEMPS WERE ALSO TRICKY AND DIDN'T TRY TO GET TOO CUTE...JUST IN VICINITY OF CONSENSUS MOS NUMBERS THROUGH MID WEEK WITH CONFIDENCE WAVERING ON EXTENT OF RAINFALL...FRONTAL POSITION...ETC DURING THIS TIME FRAME. NEXT UPPER TROUGH PUNCHES THROUGH THE WRN STATES AND INTO THE ROCKIES BY THURS INTO FRI. THIS WILL SHOOT OLD BOUNDARY NWD AS A WARM FRONT AND WANED POPS/WARMED MAX TEMPS WITH MORE PARTLY CLOUDY CONDITIONS. SYSTEM WILL EJECT WELL NWD AGAIN...BUT LOOKS LIKE A DRYLINE/POTENTIAL SEVERE WEATHER EVENT COULD OCCUR THURS AFTN INTO FRI MORNING IF ALL PANS OUT...BUT THIS IS STILL A WAYS OFF AND CONFIDENCE IS LOW WITH THIS SYSTEM AND PARAMETERS INTO NEXT WEEKEND. GENERALLY MADE LITTLE CHANGES THIS FAR OUT. && .FWD WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM 10 AM SUNDAY TO 6 PM SUNDAY FOR TXZ091-TXZ092- TXZ093-TXZ100-TXZ101-TXZ102-TXZ103-TXZ104-TXZ115-TXZ116-TXZ117- TXZ118-TXZ119-TXZ129-TXZ130-TXZ131-TXZ132-TXZ133-TXZ134-TXZ141- TXZ142-TXZ143-TXZ144-TXZ145-TXZ156-TXZ157-TXZ158-TXZ159. && $$ /05 tx AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BLACKSBURG VA 1222 PM EST SUN MAR 26 2006 .AVIATION... COLD AIR ALOFT AND ABUNDANT MOISTURE WILL CONTINUE TO PRODUCE WIDESPREAD STRATO-CU UNTIL LOSS OF HEATING THIS EVENING. THIS WILL RESULT IN LINGERING MVFR CEILINGS BLF/LWB WITH MAINLY VFR LEVELS ELSEWHERE. SCATTERED -SHSN WILL LINGER SE WVA THIS AFTERNOON WITH ISOLATED -SHRA/SPRINKLES ELSEWHERE. SKIES CLEAR ACROSS EASTERN SITES OVERNIGHT INTO MONDAY...WHILE LOW CLOUDS SLOWLY ERODE INTO VFR THIS EVENING AND THEN CLEAR BY MORNING. GUSTY NW WINDS SHOULD DIMINISH THIS EVENING AND BECOME LIGHT/VRBL OVERNIGHT INTO TUESDAY AS HIGH PRESSURE FINALLY BUILDS IN FROM THE WEST. && .PREV DISCUSSION... (ISSUED 959 AM EST SUN MAR 26 2006) SHORT TERM /REST OF TODAY/... RADAR SHOWING ONLY PATCHY SNOW SHOWERS AROUND THIS MORNING ALTHO THE HEAVIEST ACROSS PARTS OF THE NEW RIVER VALLEY PER DEEP NW FLOW AND MOISTURE/INSTABILITY UNDER INVERSION ALOFT OFF 12Z RAOB. AS NEXT S/W OFF VAPOR LOOP SWINGS BY TO THE EAST LATER THIS MORNING...SHOULD SEE NW FLOW ALOFT WEAKEN THRU THE AFTERNOON AS 85H ADVECTION TURNS MORE NEUTRAL WHILE MOISTURE DEPTH SLOWLY DECREASES. HOWEVER FORECAST RAOBS CONTINUE TO SHOW DECENT LAPSES DESPITE DEPARTING 5H COLD POOL SO SOME ADDITIONAL ISOLATED -SHSN/-RASH LIKELY OVER THE RIDGES. ELSEWHERE...CLEAR SKIES SHOULD FILL BACK IN WITH CU GIVEN HEATING AS FORECAST RAOBS INDICATE HIGH BASED RH LAYER THIS AFTERNOON FROM THE BLUE RIDGE EAST. THUS WILL UPDATE TO LOWER POPS OVER THE WEST SINCE THE LATEST RUC/NAM PRODUCE ONLY SPOTTY PRECIP AFTER 18Z AND REMOVE MORNING WORDING. FINALLY LOOKS LIKE LAST REAL CHILLY DAY FOR A WHILE ESPCLY MOUNTAINS WHERE CLOUD SHIELD LIKELY TO HOLD MOST IN THE 35 TO 45 RANGE. THICKNESS ONLY SUPPORTING LOWER 50S SE AND IF CLOUDS FILL IN MORE/FASTER WILL BE EVEN COOLER...SO PLAN TO LOWER HIGHS A BIT ACROSS THE AREA FOR THE AFTERNOON. PREV DISCUSSION... (ISSUED 636 AM EST SUN MAR 26 2006) AVIATION... KRLX RADAR CONTINUES TO SHOW SNOW SHOWERS MOVING INTO THE GREENBRIER VALLEY FROM THE NORTHWEST. MODEL MAINTAIN THE LOW LEVEL UPSLOPE WINDS THROUGH THE DAY BUT VISIBILITIES WILL IMPROVE TO VFR BY AFTERNOON. CEILINGS AT LWB AND BLF WILL BE SLOWER TO IMPROVE BUT AFTER SUNSET THE STRATOCUMULUS WILL BEGIN TO DISSIPATE AND BY MORNING BOTH LWB AND BLF WILL BE VFR. CUMULUS WILL LASO DEVELOP THIS AFTERNOON IN THE EAST BUT CEILINGS WILL REMAIN VFR AT ROA...LYH AND DAN. ISOLATED SHOWERS ARE POSSIBLE IF CONVECTION IS DEEP ENOUGH BUT THE CHANCE IS TOO LOW TO INCLUDE IN THE TAFS. PREV DISCUSSION... (ISSUED 218 AM EST SUN MAR 26 2006) SHORT TERM /TODAY THROUGH TUESDAY NIGHT/... NORTHWEST WINDS FROM THE SURFACE THROUGH 850 MB CONTINUE THROUGH TONIGHT. NO CHANGES NEEDED TO THE CHANCE OF SNOW SHOWERS IN THE FAVORED WESTERN UPSLOPE AREAS. BUFKIT AND RELATIVE HUMIDITY FORECASTS ARE STILL SHOWING SOME MOISTURE TODAY...EVEN EAST OF THE BLUE RIDGE. EVEN IF THERE AREA SOME BREAKS IN THE EAST THIS MORNING. THERE WILL BE ENOUGH RESIDUAL INSTABILITY FROM THE RETREAING UPPER LOW FOR THE STRATOCUMULUS TO FILL IN DURING THE AFTERNOON. WILL NOT BE TOO AGRESSIVE CLEARING OUT THE CLOUD COVER IN THE GRIDS. MONDAY AFTERNOON THROUGH TUESDAY MORNING THE COUNTY WARNING AREA IS IN THE LEFT FRONT REGION OF THE UPPER JET. BEST 840 MB CONVERGENCE IN ON TUEDSDAY NIGHT AS THE COLD FRONT COMES THROUGH. HIGH RELATIVE HUMIDITIES BELOW 700 MB SPREAD ACROSS THE COUNTY WARNING AREA ON TUEDAY MORNING WITH THE BEST 850-700 MB Q-VECTOR FORCING ARRIVING IN THE WESTERN COUNTIES BY 18Z TUESDAY. GFS IS STILL A LITTLE FSTER BRINGING THE UPPER TROF THROUGH BUT NO CHANGES IN THE TIMING IN THE FORECAST AT THIS POINT. TEMPERATURES WILL BE MODERATING THROUGH THE FIRST HALF OF THE WEEK. 500 MB HEIGHTS RISE TONIGHT AND SUNDAY...THEN EVEN WHEN THE NEXT UPPER LOW COMES ACROSS ON TUESDAY AND TUEDSAY NIGHT...NO REAL COLD AIR BEHIND IT. THE SURFACE HIGH WILL BE CENTERED OVER THE FORECAST AREA BY THE END OF THE DAY MONDAY. EVEN MONDAY MORNING...DEEPER WESTERN VALLEYS WILL LIKELY DECOUPLE AND MAY BE SLIGHTLY COOLER THAN GUIDANCE. LONG TERM /WEDNESDAY THROUGH SATURDAY/... NO CHANGES AT THIS TIME. AVIATION... NORTHWEST FLOW AND ABUNDANT MOISTURE TO CONTINUE LIGHT SNOW SHOWERS ON WESTERN SLOPES THROUGH SUNDAY MORNING. MVFR VIS/CLOUDS ON WESTERN SLOPE WHILE MVFR CLOUDS ELSEWHERE ACROSS THE MOUNTAINS. EAST WILL REMAIN VFR. TAIL END OF UPPER LEVEL LOW WITH ASSOCIATED COLD POOL STILL LINGERING IN THE AREA SUNDAY AFTERNOON. WITH HEATING...ISOLATED/SCATTERED CONVECTIVE SHOWERS TO IGNITE DURING THE AFTERNOON THEN DISSIPATE AROUND SUNSET. WILL KEEP TAFS DRY WITH CB ANNOTATION WITH CLOUDS. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ JH va AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BLACKSBURG VA 959 AM EST SUN MAR 26 2006 .SHORT TERM /REST OF TODAY/... RADAR SHOWING ONLY PATCHY SNOW SHOWERS AROUND THIS MORNING ALTHO THE HEAVIEST ACROSS PARTS OF THE NEW RIVER VALLEY PER DEEP NW FLOW AND MOISTURE/INSTABILITY UNDER INVERSION ALOFT OFF 12Z RAOB. AS NEXT S/W OFF VAPOR LOOP SWINGS BY TO THE EAST LATER THIS MORNING...SHOULD SEE NW FLOW ALOFT WEAKEN THRU THE AFTERNOON AS 85H ADVECTION TURNS MORE NEUTRAL WHILE MOISTURE DEPTH SLOWLY DECREASES. HOWEVER FORECAST RAOBS CONTINUE TO SHOW DECENT LAPSES DESPITE DEPARTING 5H COLD POOL SO SOME ADDITIONAL ISOLATED -SHSN/-RASH LIKELY OVER THE RIDGES. ELSEWHERE...CLEAR SKIES SHOULD FILL BACK IN WITH CU GIVEN HEATING AS FORECAST RAOBS INDICATE HIGH BASED RH LAYER THIS AFTERNOON FROM THE BLUE RIDGE EAST. THUS WILL UPDATE TO LOWER POPS OVER THE WEST SINCE THE LATEST RUC/NAM PRODUCE ONLY SPOTTY PRECIP AFTER 18Z AND REMOVE MORNING WORDING. FINALLY LOOKS LIKE LAST REAL CHILLY DAY FOR A WHILE ESPCLY MOUNTAINS WHERE CLOUD SHIELD LIKELY TO HOLD MOST IN THE 35 TO 45 RANGE. THICKNESS ONLY SUPPORTING LOWER 50S SE AND IF CLOUDS FILL IN MORE/FASTER WILL BE EVEN COOLER...SO PLAN TO LOWER HIGHS A BIT ACROSS THE AREA FOR THE AFTERNOON. && .PREV DISCUSSION... (ISSUED 636 AM EST SUN MAR 26 2006) AVIATION... KRLX RADAR CONTINUES TO SHOW SNOW SHOWERS MOVING INTO THE GREENBRIER VALLEY FROM THE NORTHWEST. MODEL MAINTAIN THE LOW LEVEL UPSLOPE WINDS THROUGH THE DAY BUT VISIBILITIES WILL IMPROVE TO VFR BY AFTERNOON. CEILINGS AT LWB AND BLF WILL BE SLOWER TO IMPROVE BUT AFTER SUNSET THE STRATOCUMULUS WILL BEGIN TO DISSIPATE AND BY MORNING BOTH LWB AND BLF WILL BE VFR. CUMULUS WILL LASO DEVELOP THIS AFTERNOON IN THE EAST BUT CEILINGS WILL REMAIN VFR AT ROA...LYH AND DAN. ISOLATED SHOWERS ARE POSSIBLE IF CONVECTION IS DEEP ENOUGH BUT THE CHANCE IS TOO LOW TO INCLUDE IN THE TAFS. PREV DISCUSSION... (ISSUED 218 AM EST SUN MAR 26 2006) SHORT TERM /TODAY THROUGH TUESDAY NIGHT/... NORTHWEST WINDS FROM THE SURFACE THROUGH 850 MB CONTINUE THROUGH TONIGHT. NO CHANGES NEEDED TO THE CHANCE OF SNOW SHOWERS IN THE FAVORED WESTERN UPSLOPE AREAS. BUFKIT AND RELATIVE HUMIDITY FORECASTS ARE STILL SHOWING SOME MOISTURE TODAY...EVEN EAST OF THE BLUE RIDGE. EVEN IF THERE AREA SOME BREAKS IN THE EAST THIS MORNING. THERE WILL BE ENOUGH RESIDUAL INSTABILITY FROM THE RETREAING UPPER LOW FOR THE STRATOCUMULUS TO FILL IN DURING THE AFTERNOON. WILL NOT BE TOO AGRESSIVE CLEARING OUT THE CLOUD COVER IN THE GRIDS. MONDAY AFTERNOON THROUGH TUESDAY MORNING THE COUNTY WARNING AREA IS IN THE LEFT FRONT REGION OF THE UPPER JET. BEST 840 MB CONVERGENCE IN ON TUEDSDAY NIGHT AS THE COLD FRONT COMES THROUGH. HIGH RELATIVE HUMIDITIES BELOW 700 MB SPREAD ACROSS THE COUNTY WARNING AREA ON TUEDAY MORNING WITH THE BEST 850-700 MB Q-VECTOR FORCING ARRIVING IN THE WESTERN COUNTIES BY 18Z TUESDAY. GFS IS STILL A LITTLE FSTER BRINGING THE UPPER TROF THROUGH BUT NO CHANGES IN THE TIMING IN THE FORECAST AT THIS POINT. TEMPERATURES WILL BE MODERATING THROUGH THE FIRST HALF OF THE WEEK. 500 MB HEIGHTS RISE TONIGHT AND SUNDAY...THEN EVEN WHEN THE NEXT UPPER LOW COMES ACROSS ON TUESDAY AND TUEDSAY NIGHT...NO REAL COLD AIR BEHIND IT. THE SURFACE HIGH WILL BE CENTERED OVER THE FORECAST AREA BY THE END OF THE DAY MONDAY. EVEN MONDAY MORNING...DEEPER WESTERN VALLEYS WILL LIKELY DECOUPLE AND MAY BE SLIGHTLY COOLER THAN GUIDANCE. LONG TERM /WEDNESDAY THROUGH SATURDAY/... NO CHANGES AT THIS TIME. AVIATION... NORTHWEST FLOW AND ABUNDANT MOISTURE TO CONTINUE LIGHT SNOW SHOWERS ON WESTERN SLOPES THROUGH SUNDAY MORNING. MVFR VIS/CLOUDS ON WESTERN SLOPE WHILE MVFR CLOUDS ELSEWHERE ACROSS THE MOUNTAINS. EAST WILL REMAIN VFR. TAIL END OF UPPER LEVEL LOW WITH ASSOCIATED COLD POOL STILL LINGERING IN THE AREA SUNDAY AFTERNOON. WITH HEATING...ISOLATED/SCATTERED CONVECTIVE SHOWERS TO IGNITE DURING THE AFTERNOON THEN DISSIPATE AROUND SUNSET. WILL KEEP TAFS DRY WITH CB ANNOTATION WITH CLOUDS. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ JH va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 854 PM CST SUN MAR 26 2006 .UPDATE... RATHER IMPRESSIVE SYSTEM CONTINUES TO SPIN OUT OF WYOMING INTO NEBRASKA THIS EVENING ON WATER VAPOR. STRONG MOIST ADVECTION/ISENTROPIC LIFT /295K/ BRINGING NARROW AND MODIFIED MOISTURE AXIS OFF THE SOUTHERN PLAINS INTO THE SYSTEM...WITH A RAPID EXPANSION OF THE CLOUD DECK /10KFT/ IN THE LAST FEW HOURS ACROSS IOWA. REGIONAL RADARS NOW PICKING UP ON BAND OF RAIN/DRIZZLE IN THE STRONGEST JUXTAPOSITION OF DEEP LAYER QG FORCING/ISENTROPIC LIFT IN THE LEFT EXIT REGION OF THE APPROACHING JET ACROSS ERN NEB. NEW 00Z NAM/RUC CONTINUE TO CONFIRM GFS-LED TREND OF STEADY SINK SOUTH OF THIS SYSTEM...WITH PRONOUNCED MID/UPPER RIDGING HOLDING FIRM OVER NRN CWA THROUGH TOMORROW. SHIFTED POPS SOUTH/WEST TONIGHT OUT OF WRN WISC...AND CONFINED LIKELY POPS TO FAR WRN CWA IN ACCORDANCE WITH DISTANCE/SPEED OF STRONGEST FORCING OVERLAID WITH EXPANDING ECHOES OVER ERN NEB. ALSO DROPPED NRN CWA POPS TOMORROW...RATHER SIGNIFICANTLY IN SOME INSTANCES IN AGREEMENT WITH STRONG SWRD TREND IN OPNL RUNS. PTYPE STILL A HUGE CONCERN...NOT SO MUCH WHAT SNOW COULD ACCUMULATE /LITTLE IF ANY/ BUT FOR WHAT COMMUTERS MAY SEE FOR THE MONDAY MORNING DRIVE. HAVE CONTINUED TO MENTION RA/SN AS BOUNDARY LAYER/MAX WET BULB TEMPS TEETER CLOSE TO THE THRESHOLD. TRENDS SEEM TO SUGGEST INCREASING BOUNDARY LAYER FLOW AND CLOUDS SHOULD KEEP MINS UP AND THEREFORE ALL RAIN...BUT RIDGE TOPS/HIGHER SERN MN TERRAIN COULD YIELD SOME WET SNOW AS PER FORECAST. QUICK TRANSITION BACK TO RAIN FOR WHAT LITTLE SNOW MAY BE AROUND ON MON MORNING. UPCOMING SHIFT MAY NEED TO FURTHER SHIFT POPS SOUTH. NERN IA...SEEMS A HIGH CONFIDENCE AREA FOR 0.1 TO 0.2 OF RAIN...GETS A LOT MORE QUESTIONABLE HEADING NORTHEAST FROM THERE. FORCING REALLY PINCHES OFF TO THE NORTH AS THE MAIN MOISTURE TRANSPORT AXIS LAYS OUT AHEAD OF THE JET STREAK TO THE SOUTH/EAST OF HERE. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ BINAU wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 1255 AM MON MAR 27 2006 .AVIATION... HIGH PRES MOVG ACROSS THE CWA TONIGHT WITH CLR SKIES AND LIGHT WINDS RESULTING IN GOOD RADIATIONAL COOLING. LOW LEVELS QUITE DRY SO EXPECTING ONLY PATCHY GROUND FOG IN RURAL AREAS OVERNIGHT AND LEFT TAFS WITH NO VSBY RESTRICTIONS. LOW OVER WRN NEBRASKA EXPECTED TO MOVE ESE INTO IL BY END OF THE PERIOD. AREA OF RAIN IN LOW LEVEL WAA REGIME AHEAD OF THE LOW SHOULD SPREAD INTO NRN INDIANA LATE IN THE TAF PERIOD WITH CIGS LOWERING TO MVFR AND EVENTUALLY SOME FOG FORMING, BUT THAT SHOULD BE BEYOND THE TAF PD. && .PREV DISCUSSION... SHORT TERM... TONIGHT AND MONDAY RATHER BENIGN SHORT TERM WEATHER AS SURFACE AND UPPER LEVEL RIDGING MOVE INTO THE AREA TONIGHT. FORECAST CHALLENGE WILL ACTUALLY BE CLOUD COVER EARLY THIS EVENING DUE TO WIDESPREAD INSTABILITY CUMULUS AND RESIDUAL STRATOCUMULUS ASSOCIATED WITH SLOW MOVING VORT MAX ALONG SOUTHEAST SHORE OF LAKE MICHIGAN. MODELS DID A POOR JOB HANDLING THIS VORTICITY MAX AND ASSOCIATED CLOUD COVER. VISIBLE SATELLITE LOOPS SHOW NICE CIRCULATION MOVING SOUTH ALONG THE EASTERN SHORE OF LAKE MICHIGAN. AT 19Z THIS CIRCULATION WAS JUST OFFSHORE OF HOLLAND MICHIGAN AND APPEARED TO BE DRIFTING A BIT SOUTHWEST. LATEST RUC40 EVEN STRUGGLING WITH A POSITION SOUTH OF CHICAGO AT 19Z...THOUGH IT DOES HAVE AN ELONGATED AXIS OF VORTICITY NORTHEAST THROUGH SOUTHERN MICHIGAN. A SECONDARY VORT MAX HAS SHOWN UP IN THE CU FIELD THIS AFTERNOON NEAR THE TRI STATE BORDER AREA. THIS CIRCULATION HAS BEEN SLOW TO MOVE BUT AIDING IN CONVERGENCE AND CUMULUS DEVELOPMENT THIS AFTERNOON. MOST OF THE CU FIELD IS VERY CELLULAR IN NATURE AND EXPECT ITS DISSIPATION WITH SUNSET AS DIURNAL HEATING IS LOST. THIS SHOULD LEAVE A SMALL AREA OF CLOUDS DIRECTLY ASSOCIATED WITH THE VORT MAX OVER THE NORTHWEST AREA. AS VORT MAX SINKS SOUTH AND SUBSIDENCE FROM RIDGING MOVES IN...FEEL THIS AREA WILL GRADUALLY DISSIPATE AS WELL. WILL HAVE REMAINDER OF AFTERNOON HOURS AS MOSTLY CLOUDY AND DECREASE MOST OF THE CLOUDS THROUGH 01Z...TRENDING TO MOSTLY CLEAR BY MID EVENING. WITH THE RIDGE DIRECTLY OVER TOP SHOULD SEE WINDS BECOME CALM ALONG WITH THE MOSTLY CLEAR SKIES. THIS SHOULD ALLOW FOR GOOD RADIATIONAL COOLING TONIGHT WITH LOW TEMPERATURES A FEW DEGREES BELOW COOLEST MOS...INTO THE MIDDLE 20S. MONDAY WILL BEGIN NICE WITH LIGHT WINDS AND MOSTLY SUNNY SKIES IN THE MORNING. NEXT SHORT WAVE WILL APPROACH WITH HIGH CLOUDS INCREASING DURING THE AFTERNOON. TEMPERATURES SHOULD APPROACH NORMAL VALUES IN THE MID 50S BEFORE THICKEST CLOUD COVER REACHES THE AREA. WHILE LOW LEVELS REMAIN RATHER DRY FOR MOST OF THE DAY...SATURATION DOES BEGIN TO OCCUR TOWARD 00Z SO HAVE LEFT THE SMALL CHANCE OF LIGHT SHOWERS IN THE FAR WEST STARTING AFTER 21Z. LONG TERM... MONDAY NIGHT THROUGH SUNDAY ANOTHER SIGNIFICANT PATTERN EVOLUTION WILL BE UNDERWAY IN THE MEDIUM RANGE PERIOD WHICH WILL ALLOW TEMPERATURES TO SWING FROM THE CURRENT BELOW AVERAGE VALUES TO ABOVE NORMAL BY MID WEEK. CURRENT PATTERN IS TYPICAL OF AN END STAGE MATURE -AO EPISODE WITH ALL THE NEGATIVE HEIGHT ANOMALIES IN THE NORTHERN HEMISPHERE CLUSTERED WITHIN A BELT IN THE MID LATITUDES WITH THE HIGH LATITUDES AND THE ARCTIC DOMINATED BY POSITIVE HEIGHT ANOMALIES. AS THIS LATEST PATTERN REGIME FADES THE BLOCKING PATTERN WHICH HAS BEEN IN PLACE ACROSS NOAM WILL BREAK DOWN WITH THE PERSISTENT COLD CLOSED LOW OVER THE GREAT LAKES FINALLY EJECTING OFF THE EAST COAST. AS THIS BLOCKING PATTERN BREAKS DOWN A PARADE OF SIGNIFICANT WAVES OF PACIFIC ORIGIN WILL BEGIN TO PROGRESS FROM WEST TO EAST ACROSS NOAM. IN ADDITION... SIGNIFICANT TROPICAL FORCING MANIFESTED IN WATER VAPOR IMAGERY AS A PLUME OF MOISTURE EXTENDING ACROSS THE HAWAIIAN ISLANDS WILL LIKELY CONTRIBUTE MOISTURE AND WAVE PACKETS TO THE PACIFIC WAVE TRAIN. LOOKING AT THE DAILIES THE FIRST IN A SERIES OF PACIFIC WAVES IS NOW CROSSING THROUGH THE INTERMOUNTAIN WEST AND WILL REMAIN PROGRESSIVE AS THE LAST VESTIGE OF THE CENTRAL CONUS OMEGA BLOCK QUICKLY DISSOLVES. NAM/GFS IN GOOD AGREEMENT NOW IN TAKING A CLOSED MID LEVEL LOW FROM CENTRAL ILLINOIS TO SOUTHERN OHIO MON NGT AND TUE. MID LEVEL LOW AND SURFACE REFLECTION WILL BE STEADILY FILLING AS THEY CROSS THE REGION WITH AN OVERALL WEAKENING IN DYNAMICS WITH TIME. NONETHELESS A PERIOD OF DPVA AHEAD OF THE WAVE COUPLED WITH FRONTOGENETICAL FORCING ALONG THE NORTHERN PERIPHERY OF THE LOW TRACK WILL PRODUCE A PERIOD OF RAIN ACROSS THE CWA FROM MON EVENING THROUGH TUE MORNING. ANY PRECIP WILL FALL AS LIQUID GIVEN THE SIGNIFICANT WARM LAYER IN THE LOWEST LEVELS PROMOTING FULL MELTING. HAVE INCREASED POPS TO HIGH LIKELY FOR MON NGT AND ALSO INCREASED POPS TO LIKELY OVER THE OHIO COUNTIES FOR TUE MORNING. ANY RAIN SHOULD END LATER TUE WITH A SURFACE HIGH BUILDING IN FOR TUE NGT AND WED. GIVEN PATTERN RECOGNITION OF A FILLING LOW AND MODEL SOUNDINGS...EXPECT SIGNIFICANT LOW LEVEL MOISTURE AND CLOUD COVER TO LINGER TUE NGT AND EVEN INTO WED MORNING. NEXT SIGNIFICANT WAVE NOW CROSSING THE GULF OF ALASKA WILL EMERGE ONTO THE HIGH PLAINS WED NGT. MEDIUM RANGE GUIDANCE IS COMING INTO REASONABLE AGREEMENT WITH THE MOVEMENT OF THIS FEATURE. BOTH THE GEM ENSEMBLES AND GFS ENSEMBLES SHOWING A MAJORITY CLUSTERING OF MEMBERS AROUND A COMMON PATH THROUGH THE UPPER MIDWEST WITH THE LATEST OPERATIONAL RUNS WELL WITHIN THE ENSEMBLE ENVELOPE. BASIC EVOLUTION WILL TAKE A STRONG MID LEVEL TROUGH AND SWING IT THROUGH THE PLAINS AND UPPER MISSISSIPPI VALLEY THU THROUGH FRI WITH A TRAILING COLD FRONT CROSSING OUR REGION ON FRIDAY. AS IS TYPICALLY THE CASE IN THE OHIO VALLEY...MEDIUM RANGE GUIDANCE CONTINUES TO SUGGEST PRE-FRONTAL TROUGH DEVELOPMENT WILL OCCUR AND BE THE FOCUS FOR CONVECTION. CURRENT GRIDS HAVE THE SITUATION WELL IN HAND AND WILL MAKE VERY FEW CHANGES. CHANCE OF TSRA CONTINUES IN THE FORECAST FOR THU NGT THROUGH FRI WITH A CHANCE OF LINGERING SHRA FRI NGT. IF FUTURE MODEL ITERATIONS CONTINUE TO SUGGEST FASTER MOTION...CHANCE OF THUNDERSTORMS MAY NEED TO BE INTRODUCED THU AFTERNOON AS WELL. NEXT WEEKEND MODEL AGREEMENT BEGINS TO DECREASE RAPIDLY...WHICH IS TYPICAL OF A TRANSITIONAL PATTERN IN SPRING. GIVEN THE IMPRESSIVE LOOKING PACIFIC WAVE TRAIN AND ONGOING TROPICAL FORCING CONNECTION IN THE PACIFIC SUSPECT THERE WILL BE A THIRD SYSTEM POSSIBLY DAY 7 OR DAY 8 /SUN OR MON/. GIVEN THE DEGREE OF SPREAD AMONGST ENSEMBLE GUIDANCE WILL OPT TO HOLD OFF ON INCLUSION OF POPS FOR NOW. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SHORT TERM...LASHLEY LONG TERM....HITCHCOCK AVIATION...JT in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 228 AM MST MON MAR 27 2006 .DISCUSSION...FORECAST CONCERNS INCLUDE WIND TODAY THEN TEMPERATURES NEXT SEVERAL DAYS. A LOW PRESSURE SYSTEM OVER NEBRASKA WITH ASSOCIATED COLD FRONT EXTENDING SOUTHWESTWARD THROUGH CENTRAL KANSAS WAS MOVING SLOWLY EASTWARD AS NORTHWEST FLOW SETS UP OVER THE REGION. LATEST IR AND WATER VAPOR SATELLITE IMAGERY SHOWED THE CYCLONIC SPIN OF AFOREMENTIONED HIGH PLAINS LOW PRESSURE SYSTEM. ALSO SEEN ON SATELLITE WAS A NORTH TO SOUTH TROUGH DIGGING SOUTHWARD OFF THE WEST COAST. MODELS INITIALIZED WELL THIS MORNING WITH REGARD TO POSITION AND SLOW EAST MOVEMENT OF NEBRASKA LOW PRESSURE SYSTEM AS WELL AS WITH SYSTEM OFF THE WEST COAST. PREFERRED THE GFS MODEL SLIGHTLY OVER THE NAM40 AND UKMET FOR BETTER FORECASTED TEMPERATURES AND WINDS THROUGH THE SHORT TERM PERIODS. FIRST FORECAST CONCERN TODAY WILL BE WIND. BEHIND FRONTAL PASSAGE AS WELL AS BACKSIDE OF LOW PRESSURE SYSTEM STRONG WINDS MIXED DOWN LAST NIGHT ALONG WITH LIGHT PRECIPITATION OVER YUMA AND DUNDY COUNTIES OF FORECAST AREA. LATEST POINT SOUNDINGS ACROSS FORECAST AREA ALONG WITH KGLD VAD WIND PROFILE SHOW 40KT TO 50KT NORTHWEST WINDS JUST OFF THE SURFACE. THE RUC MODEL ALSO FORECASTS A PERIOD OF THESE WINDS TO POSSIBLY MIX DOWN TODAY AFTER SUNRISE. THEREFORE WILL ISSUE A WIND ADVISORY FOR MUCH OF THE FORECAST AREA EXCLUDING THE SOUTHWEST SECTIONS FOR TODAY. SHOULD SEE BEST WINDS EARLY IN THE WEST AND THEN GRADUALLY SPREAD EAST WITH TIME. ALSO SHOULD NOT HAVE MUCH CLOUDINESS AS SUBSIDENCE BEHIND THE DEPARTING LOW TAKES HOLD. DID NOT MAKE MUCH CHANGE IN HIGH TEMPERATURES FOR TODAY WITH TEMPERATURES A LITTLE COOLER THAN THOSE OF YESTERDAY BUT STILL IN THE 50S. SNOW FIELD HAS FINALLY BEGUN TO MAKE A RAPID DEPARTURE AND SHOULD CONTINUE TODAY. AS FOR THE REST OF THE SHORT TERM FORECAST THROUGH WEDNESDAY MADE VERY LITTLE CHANGES FROM PREVIOUS FORECAST. HIGH PRESSURE RIDGING BUILDS INTO REGION FOR TONIGHT THROUGH EARLY WEDNESDAY BEFORE NEXT SYSTEM APPROACHES AND MOVES THROUGH THE REGION. WEDNESDAY WILL SEE MORE HIGH CLOUDS MOVING THROUGH IN UPPER FLOW. SOUTH WINDS WILL INCREASE AS TROUGH DEVELOPS BY AFTERNOON IN COLORADO. HIGH TEMPERATURES WILL REMAIN MILD WITH HIGHS RANGING FROM THE MIDDLE 60S TO NEAR 70. AS FOR THE EXTENDED FORECAST PERIOD THURSDAY THROUGH SUNDAY EXTENDED MODELS STILL ADVERTISE TROUGH AND COLD FRONT TO MOVE THROUGH FORECAST AREA THURSDAY AND THURSDAY NIGHT. WILL MAINTAIN MENTION OF SLIGHT CHANCE FOR THUNDERSTORMS NORTHEAST HALF OF FORECAST AREA DURING THE DAY THURSDAY AS TROUGH AND FRONT MOVE THROUGH THE REGION. RIDGING THEN RETURNS TO THE FORECAST AREA FOR FRIDAY THROUGH SUNDAY WITH DRY WEATHER AND MILD TEMPERATURES WITH HIGHS IN THE 60S AND LOWS IN THE 30S. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...WIND ADVISORY UNTIL 5 PM MONDAY FOR KSZ001-KSZ002-KSZ003-KSZ004- KSZ013-KSZ014-KSZ015-KSZ016-KSZ028-KSZ029. NE...WIND ADVISORY UNTIL 5 PM MONDAY FOR NEZ079-NEZ080-NEZ081. CO...WIND ADVISORY UNTIL 5 PM MONDAY FOR COZ090-COZ252. && $$ LAMMERS ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 415 AM EST MON MAR 27 2006 .DISCUSSION... MAIN FCST CONCERNS SHIFT FROM CLOUDS/TEMPS THROUGH WED TO PCPN/TSTM CHANCES LATER IN THE WEEK. WV IMAGERY...RUC ANALYSIS AND 00Z RAOBS INDICATED A MID/UPR LVL LONG WAVE RDG FROM THE MS VALLEY INTO MANITOBA AND A VIGOROUS UPSTREAM SHRTWV TROF MOVING THROUGH WRN NEB. AN AREA OF MID/HIGH CLOUDS INTO LK SUPERIOR AND NRN UPR MI WAS SUPPORTED BY A WEAK SHRTWV LOCATED OVER WRN ONTARIO IN NW FLOW AHEAD OF THE RDG. AT THE SFC...A RDG DOMINATED THE GREAT LAKES WHILE A TROF SLOWLY EDGED EASTWARD FROM THE PLAINS. MDLS ARE IN GOOD AGREEMENT AT LEAST WITH THE OVERALL SCENARIO SUGGESTING THAT THE MID LEVEL LOW AND ASSOCIATED QG FORCING WILL REMAIN WELL SOUTH OF UPR MI AS IT UNDERCUTS THE RDG ON ITS WAY TOWARD IN/OH BY TUE. THIS WILL ALLOW THE SFC A SFC RDG TO PERSIST OVER THE UPR GRT LAKES THROUGH TUE WITH QUIET WEATHER IN STORE FOR UPR MI. TODAY...AFTER THE ONTARIO SHRTWV DEPARTS...EXPECT THAT THAT MID LVL AND SFC RDGING AND VERY DRY AIR IN PLACE WILL KEEP SKIES MOSTLY SUNNY. SO...ABUNDANT LATE MARCH SUNSHINE SHOULD AGAIN BE ABLE TO PROVIDE MIXING TOWARD 850-800 MB...SIMILAR TO YESTERDAYS OBSERVED SOUNDINGS. THIS WOULD SUPPORT TEMPS TOWARD THE HIGHER ETA GUIDANCE VALUES IN THE MID TO UPPER 40S. TONIGHT...THERE MAY BE SOME INCREASE IN MID/HIGH CLOUDS...ESPECIALLY NEAR THE WI BORDER. OTHERWISE...MOSTLY CLEAR TO PARTLY CLOUDY SKIES SHOULD ALLOW GOOD RADIATIONAL COOLING CONDITIONS WITH LIGHT/VRBL WINDS. SO...EXPECT TEMPS TO FALL NEAR GUIDANCE VALUES...LOWER THAN PREVIOUS FCSTS. TUE...EVEN THOUGH THE GFS/NAM HINTS AT SOME INCREASE IN 925-850 MB MOISTURE AS THE SFC RDG SAGS TO THE SOUTH...IT SEEMS DOUBTFUL THAT IT WILL BE ENOUGH TO BRING SIGNIFICANT INCREASE IN CLOUDS. SO...WITH SIMILAR THERMAL PRFL...PERSISTENCE AND MDLS TEMP GUIDANCE SEEMED REASONABLE. TUE NIGHT INTO WED...PATTERN PROGRESSION WITH THE MID LVL TROF MOVING INTO THE ROCKIES AND RDGING OVER THE CNTRL CONUS WILL BRING INCREASING SW FLOW TOWARD THE WRN GRT LAKES WITH MODEST INCREASE IN MOISTURE. INCREASING WAA AND DOWNSLOPE FLOW WILL BOOST TEMPS TO NEAR 50F WED AFTERNOON. WED NIGHT...WITH A MORE AMPLIFIED PATTERN DEVELOPING...THE ECMWF/UKMET WERE PREFERRED WHICH KEEP THE MOISTURE AXIS AND ASSOCIATED PCPN CHANCES A BIT FARTHER WEST THAN THE GFS. THU INTO FRI...UKMET/GFS/ECMWF/CANADIAN MDLS ARE IN BETTER AGREEMENT WITH POSITION OF THE MID LVL TROF AND SFC LOW. THE 27/00Z GFS/ECMWF DEVELOP DECENT LOW LVL JET BY THU NIGHT WITH H8 DEWPOINTS TO AROUND 8C PUSHING INTO UPR MI. INCREASING POTENTIAL FOR ELEVATED CONVECTION WITH LOW LVL THETA-E RDG WARRANTS MENTION OF TSTMS. BY FRI...DYNAMICS ASSOCIATED WITH SHRTWV LIFTING TOWARD THE WRN LAKES WILL AGAIN SUPPORT POTENTIAL FOR ADDITIONAL TSTMS. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ JLB mi AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 1035 PM CST SUN MAR 26 2006 .UPDATE... INSPECTION OF THE LOCAL 88D MOSAIC SHOWS THAT PCPN HAS DEVELOPED PRETTY MUCH ON SCHEDULE TO THE SW OF THE FA IN RGN OF DEFORMATION AND WAA IN ADVANCE OF UPR LO EVIDENT IN WV IMAGERY OVR WRN NE ATTM. SFC OBS SHOWING THAT PCPN IS HAVING MINIMAL IMPACT...WITH CIGS ONLY REDUCED TO 3 TO 5 KFT AND NO VIS RESTRICTION. 00Z NAM HAS FOLLOWED THE TREND OF THE 18Z NAM/GFS...AS WELL AS THE LATEST RUC RUNS...WHICH SHOVE THE BULK OF THE FORCING ASSOC WITH THIS SYSTEM TO THE S OF THE FA...WITH SOME H7 OMEGA REMAINING ACRS SWRN AND S CNTRL MN. APPEARS THAT THERE WILL BE A RATHER SHARP CUT-OFF IN THE PCPN/NO PCPN RGN...ESPECIALLY ACRS THE E CNTRL MN AND W CNTRL WI COUNTIES. AS A RESULT...HAVE RETOOLED THE POP GRIDS THRU MON AFTN...ACCORDING TO THE LATEST 88D/SFC OB TRENDS...AS WELL AS THE LATEST MDL DATA. WITH CLOUD COVER ALSO EXPECTED TO KEEP OVRNGT TEMPS ABV FRZ ACRS W CNTRL MN...REMOVED ALL MENTION OF FRZ PCPN...INSTEAD LEAVING A MIX OF RAIN/SNOW ACRS THE AREA DURG VARIOUS TIME FRAMES. UPDATED PRODUCTS ALREADY AVBL. THANKS FOR THE COLLAB ARX. KAT && .PREV DISCUSSION... /ISSUED 315 PM CST SUN MAR 26 2006/ DISCUSSION...TONIGHT THROUGH WEDNESDAY PRIMARY CONCERN IN SHORT RANGE CONTINUES TO BE LOW PRESSURE SYSTEM PASSING NEARBY ON MONDAY AND ITS IMPACT ON PRECIPITATION TYPE AND TIMING. MORNING H5 ANALYSIS AND CURRENT GOES WV LOOP SHOWS SYSTEM OF INTEREST SPINNING ACROSS CENTRAL WY WITH UPGLIDING MOISTURE ENTERING THE UPPER MISSISSIPPI VALLEY. VIS LOOP SHOWS SOME ASSOCIATED MID-LEVEL CLOUDS OVER THE DAKOTAS BUT NO 88D RETURNS AT PRESENT. ATMOSPHERIC PROFILE OVER CWA NOT ALL THAT DRY AS SOME CU SEEN AND MORNING RAOBS INDICATED NO REAL DRY AIR INTRUSION AFTER THE LOW CLOUDS OF THE PAST FEW DAYS FINALLY ERODED. SO DO NOT THINK IT WILL TAKE LONG TO SATURATE TONIGHT AS MODEL PROGGED PWS ARE IN THE ORDER OF 0.5 TO 0.7 INCHES AND MIXING RATIOS ON LOW LEVEL THETA LAYERS OF CLOSE TO FOUR G/KG. HOWEVER FORCING IS LACKING DUE TO SYSTEM BEING STACKED AND DWINDLING WITH EACH SUCCESSIVE MODEL SOLUTION. UPPER LEVEL JET REMAINS WELL SOUTH WITH LEFT EXIT DIFFLUENT REGION AND ASSOCIATED H8-H5 OMEGA PEAKING OVER IA AND FAR SOUTHERN CWA. MODELS GENERALLY IN GOOD AGREEMENT AS 12Z AND 18Z NAM SOLUTIONS COMING IN LINE WITH THE GFS IN HAVING THE SYSTEM GLIDE ESE OVER IA. SOME WIDE HPC SREF SPREADS IN QPF LOCATION AND AMOUNT...BUT GENERALLY WENT WITH LIGHTER AMOUNTS AND LATER ONSET TIME DUE TO NO REAL AREA OF FOCUS. BUFKIT SNDGS ON THE VARIOUS MODELS INDICATE RA OR SN POSSIBILITIES. IN FAR WEST WHERE RUC AND NAM INDICATE OVERNIGHT LLJ OF 50KT...A PROGGED WARM LAYER OF 2-3C IS ADVECTED IN. SREF DOMINANT PRECIP TYPE DOES INDICATE SOME ZR WITH THIS...SO THEREFORE HAVE INTRODUCED THE CHC FROM 8Z THROUGH DAWN IN W AND NW ZONES. PRECIP CHANCES LAST ALL OF MONDAY AND INTO MONDAY NIGHT AS SYSTEM PROGGED TO MOVE SLOWLY...WITH BEST CHANCES GENERALLY IN SOUTHERN HALF OF CWA AND BEFORE 18Z MON. AFTER THAT POINT ASSOCIATED INVERTED SFC TROUGH PASSES AND DRIER AIR STARTS TO MOVE IN. PRECIP TYPE COULD SWITCH AROUND A FEW TIMES DURING THE DURATION OF THIS EVENT DUE TO DIABATIC EFFECTS AND DIURNAL TRENDS...BUT ALL IN ALL PRECIP SHOULD BE LIGHT AND GENERALLY RAIN OR SNOW WITH MAX SNOW ACCUMULATIONS AT AN INCH. LOW LEVEL CLOUDS SHOULD STICK AROUND FOR A WHILE SIMILAR TO LAST SYSTEM. LAZY LOW LEVEL FLOW SHOULD KEEP THEM THROUGH TUES AND POSSIBILY EVEN INTO TUES NIGHT. STRONG WAA STARTS IN ON WEDS AHEAD OF NEXT SYSTEM. WITH TEMPS DURING SHORT RANGE MADE ONLY MINOR TWEAKS...EDGING UP TEMPS A BIT THROUGH MON NIGHT GIVEN MAXS THIS AFTN. LONGER TERM...WEDNESDAY NIGHT THROUGH SUNDAY NIGHT THE LATEST ENSEMBLE MEMBERS OFF THE GFS AND EUROPEAN MODELS ARE SHOWING SIGNS OF DISCONTINUITY IN OVERALL UPPER AIR PATTERN OVER NORTH AMERICA DURING THE PERIOD...AS THE PATTERN BECOMES MORE PROGRESSIVE. GFS IS THE MORE AGGRESSOR OF LIFTING SYSTEM INTO THE GREAT LAKES BY SATURDAY MORNING. TIMING OF THE NEXT SYSTEM WILL BE CRITICAL THU AND FRI WITH THE LONGWAVE TROUGH AND SURFACE LOW PROJECTED TO MOVE INTO THE CENTRAL PLAINS ON THURSDAY. POPS STILL SEEM REASONABLE FOR THURSDAY AND FRIDAY DUE TO DYNAMICS ALONG WITH INCREASING INSTABLITY AHEAD OF THE SYSTEM. HOWEVER...THE BEST FORCING AND LIFT IS EXPECTED TO OCCUR OVER THE SOUTHERN HALF OF OUR FORECAST AREA. TEMPS BY THURSDAY ARE EXPECTED TO MODERATE INTO THE 50S THEN MORE TYPICAL SPRING-LIKE OVER THE UPCOMING WEEKEND. && MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SPRINGFIELD MO 358 AM CST MON MAR 27 2006 .DISCUSSION... VIGOROUS UPPER DISTURBANCE CURRENTLY TRACKING EASTWARD THIS MORNING ACROSS NEBRASKA. IN RESPONSE TO THIS FEATURE...AN AREA OF SHOWERS WITH EMBEDDED THUNDERSTORMS DEVELOPED ACROSS EASTERN KANSAS AND PUSHED INTO MISSOURI. THIS PRECIPITATION WAS FUELED BY MODEST MOISTURE TRANSPORT/CONVERGENCE ON THE NOSE OF A 55-60 KT LOW LEVEL JET AT 850 MB. IN ADDITION...UPPER DIFFLUENCE AT 250 MB WAS NOTED ON THE REGIONAL PROFILER NETWORK AS THIS AREA WAS IN THE LEFT FRONT QUAD OF THE UPPER JET. AT THE SURFACE...LOW PRESSURE WAS ALSO CENTERED OVER NEBRASKA WITH ITS ASSOCIATED COLD FRONT STRETCHING SOUTHWARD ACROSS CENTRAL KANSAS. PRIMARY SHORT TERM FORECAST CONCERNS WILL BE RAIN CHANCES AND TEMPERATURES. HELD ON TO LIKELY POPS FOR THE MORNING HOURS MAINLY EAST OF HIGHWAY 65..AS THIS AREA WILL STILL BE UNDER THE INFLUENCE OF INCREASING MOISTURE TRANSPORT AND 925-850MB THETA-E ADVECTION AHEAD OF THE APPROACHING COLD FRONT. FURTHER TO THE WEST...TRENDED POPS DOWNWARD TO LOW END CHANCES ALONG THE KANSAS BORDER AS THE RUC SHOWS DRIER AIR ADVECTING IN FROM THE WEST SHORTLY AFTER 12Z. ANY PRECIPITATION TODAY WILL BE SHOWERY IN NATURE WITH ONLY AN ISOLATED THUNDERSTORM POSSIBLE. THE NAM SHOWS SOME WEAK ELEVATED INSTABILITY WITH LI VALUES LIFTED FROM 800 MB AROUND -1 THROUGH 18Z. AS FOR TEMPERATURES...WITH DRIER AIR ADVECTING IN FROM THE WEST...AREAS ALONG THE KANSAS BORDER SHOULD SEE ENOUGH SUNSHINE TODAY TO REBOUND INTO THE LOWER 60S. WILL HAVE TO WATCH TEMPS MORE CLOSELY FURTHER EAST. FOR NOW BANKING ON CLOUD COVER HANGING ON FOR MUCH OF THE AFTERNOON WHICH WOULD LIKELY KEEP HIGHS ONLY IN THE LOW/MID 50S. TUESDAY LOOKS LIKE A TRANQUIL DAY WITH TEMPERATURES NEAR LATE MARCH NORMALS AS UPPER RIDGING TAKES HOLD IN THE WAKE OF TODAY'S SYSTEM. BY WEDNESDAY...SOUTHERLY FLOW RETURNS TO THE AREA WHICH WILL LIKELY ALLOW HIGHS TO CLIMB TO NEAR 70 ACROSS SOUTHEAST KANSAS AND MUCH OF SOUTHWEST MISSOURI. HAVE SOME SLIGHT AND LOW POPS WEDNESDAY INTO WEDNESDAY AS MOISTURE BEGINS TO RETURN NORTHWARD AHEAD OF THE NEXT UPPER SYSTEM. THE BULK OF THE LOW-LEVEL MOISTURE TRANSPORT FIELDS KEEP THE BETTER CONVERGENCE TO THE WEST...SO HIGH POPS WEREN'T WARRANTED FOR THIS PERIOD. STILL SOME MODEL DIFFERENCES REGARDING THE UPPER SYSTEM ENTERING THE PLAINS BY THURSDAY AFTERNOON. ONE THING FOR CERTAIN IS THAT THE SYSTEM WILL HAVE PLENTY OF MOISTURE TO WORK WITH. THE LATEST ECMWF TAKES THE UPPER LOW ACROSS NEBRASKA TOWARD THE UPPER MISSISSIPPI VALLEY...WHILE THE GFS TRACKS THE SYSTEM ACROSS KANSAS AND NORTHERN MISSOURI. THE GFS SOLUTION WOULD BRING A GOOD SHOT OF SEVERE WEATHER TO THE OZARKS REGION...AS 0-6KM BULK SHEAR VALUES INCREASE TO AROUND 60KTS BY 00Z FRIDAY. SAW && .AVIATION... LOCAL TOPOGRAPHY EFFECTS CONTINUE TO PRODUCE GUSTS OVER 25KT AT THE SPRINGFIELD TERMINAL EARLY THIS MORNING. LATEST RADAR IMAGERY INDICATES THAT THE BULK OF THE SHOWERS WILL REMAIN TO THE NORTH OF THE JOPLIN AND SPRINGFIELD TERMINALS THIS MORNING. ALTHOUGH A LIGHT SHOWER CANNOT BE RULED OUT. BROKEN TO OVERCAST VFR CEILINGS AROUND 6 KFT WILL PREVAIL EARLY TODAY BEFORE CLEARING OUT BY LATE MORNING. SCATTERED STRATO CUMULUS WILL REMAIN DURING THE DAY WITH MVFR CEILINGS LOCATED TO THE NORTH. GUSTY SOUTHWEST WINDS BEHIND THE FRONT WILL VEER TO WEST DURING THE DAY WITH SOME GUSTS TO 25KT. WINDS WILL SUBSIDE TONIGHT. FOSTER && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. $$ WFO SGF mo AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE JACKSON MS 950 AM CST MON 27 2006 .DISCUSSION...LATEST SATELLITE IMAGERY SHOWED A CLOSED UPPER LOW MOVING THROUGH THE MID TO UPPER PLAINS. IT WAS DRAGGING A FRONT TOWARD THE REGION. THE CWA WAS UNDER THE INFLUENCE OF A FLATTEN UPPER RIDGE PATTERN. WESTELRY FLOW IN THE MID LEVELS WAS BRINGING MID TO UPPER LEVEL CLOUDS...WHILE LOW LEVEL FLOW WAS SLOWLY TRYING THE MOISTEN THE ATMOSPHERIC COLUMN. AREA RADARS WERE PICKING UP VIRGA IN MID TO UPPER DECK CLOUDS. TEMPS SEEM TO BE RUNNING AT FORECAST SO WILL MAKE NO CHANGES. MAY SEE SOME SPRINKLES IN THE NORTHWEST LATE THIS AFTERNOON. LATEST RUC DOES NOT SHOW MUCH OF ANYTHING THERE FOR THIS AFTERNOON...BUT WILL KEEP LOW POPS THERE. .AVIATION...VFR CONDITIONS IS EXPECTED FOR THE REMAINDER OF THIS AFTERNOON WITH MID TO UPPER DECK CLOUDS ABOVE 10 KFT. WINDS WILL BE 5-10 MPH OUT OF THE SOUTH IN THE EAST TO 10-20 MPH WITH SOME HIGHER GUSTS WEST. FOR TONIGHT SHOWERS SHOULD BEGIN THIS EVENING AROUND TVR...GLH AND GWO AND THEN SHIFT SOUTH TOWARD THE I-20 CORRIDOR BEFORE DAWN. SOME MVFR CEILINGS WILL ACCOMPANY SHOWERS WITH SOME MVFR (POSSIBLY TEMPO IFR) VIS REDUCTIONS POSSIBLY ALONG AND SOUTH OF I-20 LATER TONIGHT BEFORE (OR SOUTH OF) THE AREAS OF RAIN. THERE COULD BE ENOUGH ELEVATED INSTABILITY FOR ISOLATED THUNDERSTORMS AT KGLH..KGWO LATE THIS EVENING. EXPECT THE ISOLATED STORMS TO DEVELOP OVER KCBM AFTER 08Z. BY EARLY TUESDAY MORNING THE SHOWERS WILL SPREAD OVER THE REMAINDER OF THE FORECAST AREA. WITH ISOLATED STORMS DEVELOPING SOUTH TO KJAN BETWEEN 12 AND 18Z TUESDAY. CEILINGS WILL BE MVFR. && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && 17 (PREVIOUS DISCUSSION...440 AM CST MON MAR 27 2006) .DISCUSSION... THE UNSEASONABLY COOL AND DRY STRETCH OF WEATHER OVER THE REGION WILL BE COMING TO AN END OVER THE NEXT 24 HOURS AS THE UPPER FLOW PATTERN OVER THE CENTRAL CONUS BECOMES SOMEWHAT MORE ACTIVE AND DISTURBED. DURING THIS PERIOD OF TIME A RATHER VIGOROUS UPPER ATMOSPHERIC DISTURBANCE WILL TRANSLATE QUICKLY EAST THROUGH THE MIDWEST AND OHIO VALLEY. ALMOST ALL OF THE DYNAMIC UPPER FORCING WITH THIS SYSTEM WILL REMAIN TO THE NORTH OF THE LOWER MISSISSIPPI VALLEY...BUT A FRONTAL BOUNDARY DRAPING WELL SOUTH OF THIS FEATURE (ALONG WITH ITS ATTENDANT PRECEDING WARM AIR ADVECTION ALOFT) WILL GET A MOISTENING AND LIFTING PROCESS GOING ACROSS PORTIONS OF THE ARKLAMISS. IN SHORT...THAT MEANS RAIN...ESPECIALLY LATE TONIGHT INTO TOMORROW ALONG AND NORTHWEST OF THE NATCHEZ TRACE CORRIDOR. LOOKS LIKE THIS PATTERN IS HOLDING WITH THE MOLD OF 'LA NINA' CLIMATOLOGY IN THE SENSE THAT AREAS NEAR THE COAST UP TO THE HIGHWAY 84 CORRIDOR WILL REMAIN SOUTH OF THE MAIN RAIN PRODUCTION ZONE. ALSO OF PERHAPS A LITTLE INTEREST IS THE POSSIBILITY OF ELEVATED THUNDEROUS CONVECTION ACCOMPANYING SHOWERS IN THE ARKLAMISS DELTA REGION TONIGHT AFTER MIDNIGHT...AND THEN IN MOST AREAS OUTSIDE OF SOUTHEAST MS COUNTIES LATER ON TOMORROW. INGREDIENTS FOR ANY SEVERE WEATHER LOOK TO BE IN VERY SHORT SUPPLY...SO LOOK FOR ONLY AN INCREASE IN RAIN RATES IN AREAS OF THUNDERSTORMS (AND NO HAIL OR DAMAGING WINDS). IT IS ALSO HARD TO SEE HOW RAIN TOTALS WILL BE A PROBLEM OVER THE NEXT 48 HOURS AS ONLY TOTALS OVER AN INCH OR 1.5" (AT MOST) SEEM CONCEIVABLE DURING THIS TIME (AND THEN ONLY IN IN NORTHWEST OR FAR WESTERN ZONES). SHOWERS AND CONVECTION TONIGHT AND TOMORROW SHOULD MAINLY BE CO-LOCATED WITH A THETA-E RIDGE NOSING NORTHEAST INTO THE REGION AHEAD OF THE SURFACE FRONT WITH THE SURFACE FRONT ITSELF PROBABLY NOT OOZING SOUTH INTO THE MY NORTHERN BORDERS UNTIL DAYTIME TOMORROW. THIS SURFACE FRONT WILL PROBABLY NOT MAKE IT DOWN TO THE I-20 CORRIDOR BEFORE STALLING AS SOUTHERLY FLOW OFF THE SURFACE RESPONDS TO A WEAK UPPER DISTURBANCE COMING TOWARD THE LOWER MISSISSIPPI VALLEY BY WEDNESDAY MORNING IN AN INVIGORATED SOUTHERN STREAM ALOFT. CONFIDENCE WITH PINPOINTING SHOWERS DECREASES SOME TUESDAY NIGHT IN THIS TRANSITIONAL PERIOD...BUT SHOWERS CANNOT BE RULED OUT ANYWHERE AT THIS TIME. BUT...BEFORE ALL THE UNSETTLED WEATHER...AREA RESIDENTS SHOULD ENJOY A MILDER (ALTHOUGH A BIT MORE CLOUDY) MONDAY IN COMPARISON TO THE PRIOR SEVERAL DAYS. WENT GENERALLY WITH MAV FOR HIGHS TODAY WHICH PUTS THE TEMP RANGE GENERALLY FROM THE UPPER 60S TO LOWER 70S. I REMAINED NEAR MAV FOR TEMPS TONIGHT (50 TO 55)...TOMORROW (LOW 60S TO NEAR 70) AND TOMORROW NIGHT (NEAR 50 TO MID 50S) AS WELL. AS FAR AS POPS...I DID TRY TO BEAT MAV ON THE HIGH SIDE TONIGHT AND TOMORROW IN THE "HIGH CONFIDENCE" AREAS OF RAIN MENTIONED...BUT I GENERALLY REMAINED CLOSE OTHERWISE. THERE IS A 20 PERCENT CHANCE OF SOME SHOWERS GETTING INTO FAR NORTHWEST ZONES BEFORE EVENING...BUT IF THAT OCCURS IT SHOULD BE IN THE WANING PORTION OF THE AFTERNOON. /BB/ LONGER TERM... BOUNDARY STALLS AS WARM FRONT ACROSS CENTRAL ZONES WEDNESDAY. MOISTURE DEEPENS AND WEAK WAVES SHIFT THROUGH THE FLAT RIDGE IN PLACE. LITTLE OR NO JET SUPPORT NOTED AND LOW LEVEL FLOW REMAINS RELATIVELY WEAK. THE BOUNDARY WASHES OUT WEDNESDAY NIGHT. WARMER TEMPS ON TAP FOR THURSDAY AS LOW LEVEL FLOW INCREASES. WILL SEE SURFACE DEWPOINTS LIFT INTO THE LOWER 60S BY THURSDAY AFTERNOON AS MID/UPPER FLOW BACKS IN RESPONSE TO THE LOW MOVING INTO THE SRN PLAINS. 25-30KT 850 MB JET INTENSIFIES NEAR 50 KTS THURSDAY NIGHT. DEEP LAYER SHEAR ALSO INTENSIFIES AS MID/UPPER JETS MOVE INTO PLACE. BEST SURFACE CONVERGENCE IN PLACE ACROSS THE FORECAST AREA EARLY FRIDAY MORNING BUT 850 MB FLOW HAS ALREADY VEERED TO A MORE WLY DIRECTION. THE AIR MASS REMAINS SOMEWHAT UNSTABLE WITH AN 850 MB THETAE MAX POSITIONED OVER THE AREA. LONGER TERM MODELS DISAGREE ON SRN EXTENT OF SURFACE LOW TRACK WITH EURO SHIFTING SURFACE AND UPPER LOW WELL NORTH OF THE REGION. WILL FOLLOW MORE SRN TRACK FOR NOW. THE BOUNDARY SHIFTS ACROSS THE REGION FRIDAY NIGHT AND EXITS AREA BY SUNRISE SATURDAY. BY 12Z SATURDAY NWLY FLOW FORECAST AT LOWER AND UPPER LEVELS WITH A DRY AIR MASS OVER THE AREA. MORE ZONAL FLOW SETS UP FOR SUNDAY WITH WEAK WAVES MOVING THROUGH THE FLOW. WILL KEEP SUNDAY DRY FOR NOW AS MOISTURE RETURN LOOKS DELAYED UNTIL THE BEGINNING OF THE WORK WEEK. /03/ && .AVIATION... HIGHER CLOUDS WILL FILTER EAST INTO THE ARKLAMISS REGION TODAY AND DECKS COULD BE BROKEN AT ANY TIME...ESPECIALLY WEST OF I-55. BUT LOOK FOR CEILINGS TO REMAIN ABOVE 10 KFT IN ALL AREAS OUTSIDE OF GLH...TVR AND GWO THROUGH 00Z ALTHOUGH POSSIBLY GETTING DOWN TO 5 KT IN THE HIGHLIGHTED SPOTS BY THAT TIME. SHOWERS SHOULD BEGIN THIS EVENING AROUND TVR...GLH AND GWO AND THEN SHIFT SOUTH TOWARD THE I-20 CORRIDOR BEFORE DAWN. SOME MVFR CEILINGS WILL ACCOMPANY SHOWERS WITH SOME MVFR (POSSIBLY TEMPO IFR) VIS REDUCTIONS POSSIBLY ALONG AND SOUTH OF I-20 LATER TONIGHT BEFORE (OR SOUTH OF) THE AREAS OF RAIN. /BB/ && .FIRE WEATHER... MINIMUM RH VALUES SHOULD BRIEFLY BE DOWN IN THE 20S LATER TODAY IN EASTERN MISSISSIPPI AND POSSIBLY DOWN IN THE 30S AS FAR WEST AS THE MISSISSIPPI RIVER. WINDS WILL BE A LITTLE STRONGER THAN YESTERDAY WITH GUSTS UP TO 15 TO 20 MPH NOT OUT OF THE QUESTION IN ANY SPOT. THESE COMBINATIONS DO NOT MEET RED FLAG CRITERIA ANYWHERE...BUT BURNING INTERESTS (PARTICULARLY IN EASTERN MS) SHOULD KEEP THIS IN MIND. /BB/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 70 51 66 55 / 5 45 65 46 MERIDIAN 71 49 69 53 / 0 34 58 43 VICKSBURG 71 52 66 54 / 10 53 74 50 HATTIESBURG 72 50 72 55 / 0 10 24 20 NATCHEZ 71 54 70 57 / 6 32 62 54 GREENVILLE 66 51 65 48 / 20 78 50 36 GREENWOOD 67 49 63 50 / 13 73 55 35 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ SHORT TERM:50 LONG TERM:03 ms AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 1005 AM EST MON MAR 27 2006 .SHORT TERM /REST OF TODAY THROUGH TUESDAY/... HIGH PRESSURE WILL CONTINUE TO DOMINATE THE SOUTHEAST THROUGH THE REST OF TODAY AND TONIGHT. MINOR TWEAKS TO THIS MORNINGS UPDATE TO RAISE TEMPERATURES SLIGHTLY TO MESH WITH LATEST MOS GUIDANCE. WINDS ALSO UPDATED WITH LATEST RUC GUIDANCE...BUT STILL REMAINING LIGHT DURING THE AFTERNOON. && .PREV DISCUSSION... /ISSUED 230 AM EST MON MAR 27 2006/ SHORT TERM /TODAY THROUGH WEDNESDAY/... RIDGING AT THE SFC AND ALOFT TRANSLATE EASTWARD ACRS THE CWFA TODAY ALLOWING FOR A VERY QUIET WX DAY. AFTER A CHILLY START THIS MORNING...A NOTABLY MILDER AFTERNOON IS ON TAP. DEEP FORCING AND MOISTURE STILL ON TRACK TO INCREASE ACRS THE NC MTNS AFTER MIDNIGHT WITH SHOWER CHANCES THE RESULT. A PERIOD OF SLEET OR SNOW MAY STILL OCCUR EARLY TUESDAY MORNING AS THE ATMOSPHERE MOISTENS THE INITIALLY COLD LAYER BELOW 700 MB. WILL MAINTAIN LIKELY CVRG OF SHOWERS IN THE MTNS THROUGH MIDDAY FOR NOW...BUT SUSPECT THAT WE COULD CREEP THIS UP TO CAT CVRG...ALBEIT WITH LIGHT QPF...AS LATEST SREF INDICATES A GREATER THAN 90 PERCENT CHANCE OF MEASURABLE PCPN. IT REMAINS DEBATABLE JUST MUCH SHOWER CVRG OCCURS EAST OF THE MTNS...BUT TRACK OF VORT LOOKS TO BE FAR ENUF SOUTH FOR MORE THAN JUST SCATTERED ACTIVITY INTO THE NC PIEDMONT...BUT WILL LEAVE AS CHANCE FOR NOW. A TOKEN PERIOD OF WEAK UPSLOPE FLOW DEVELOPS IN THE WAKE OF S/WV TUESDAY EVENING...OTHERWISE DEEP LAYERED DRYING SPREADS QUICKLY EAST ACRS THE REGION. WILL CONTINUE WITH A DRY FCST FOR WEDNESDAY AS UPPER RIDGING REDEVELOPS OVER THE EASTERN U.S. LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... NO SURPRISES NOTED IN THE 27/00 UTC OP GFS DEPICTION OF RETURN FLOW MOISTURE INCREASING ACRS THE SOUTHERN APPALACHIANS THURSDAY...WILL LEAVE GOING CHC POPS AS IS. MORE SOLID CHANCE POPS FOR FRIDAY TO CONTINUE AS WELL WITH MODERATELY FORCED FRONTAL/CONVECTIVE BAND PROGGED TO APPROACH FROM THE WEST. NO CHANGES MADE TO THE GOING WEEKEND FCST AS WELL. AVIATION... VFR CONDITIONS TO PERSIST THROUGH THE 06Z TAF PERIOD AS HIGH PRESSURE BUILDS IN FROM THE WEST KEEPING LIGHT NLY WINDS OVER THE AREA. CLEAR SKIES WITH ONLY A FEW LINGERING STRATOCU OVER THE N NC MTNS AND WISPS OF CI MOVING IN FROM THE WEST. SOME LINGERING MOISTURE UNDER THE SUBSIDENCE INVERSION WILL LEAD TO A LITTLE VFR STRATOCU AGAIN WITH AFTERNOON HEATING...BUT NOT TO THE EXTENT OF THE PAST TWO DAYS. ALSO IN THE AFTERNOON...LIGHT WINDS SHOULD SHIFT TO THE SW AS THE CENTER OF THE HIGH MOVES EAST AWAY FROM THE AREA. FRONTAL SYSTEM APPROACHES FROM THE WEST MONDAY NIGHT...BUT ONLY MID/HIGH LEVEL MOISTURE MOVES IN THRU 06Z. ISENTROPIC LIFT AND LOW LEVEL MOISTURE INCREASE BETWEEN 06Z AND 12Z. HOWEVER...CONCERNS REMAIN OVER WHETHER ANY PRECIP OR RESTRICTIONS DEVELOP BY THEN. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SHORT TERM...VAD sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOUISVILLE KY 213 PM EST MON MAR 27 2006 .DISCUSSION... EARLY THIS AFTERNOON...HIGH PRESSURE EXTENDED FROM THE GREAT LAKES...SOUTH ACROSS EASTERN KY INTO THE SE U.S. CLOUDS WERE ADVANCING EAST TOWARD CENTRAL KY AND SCNTRL INDIANA EARLY THIS AFTERNOON...IN ADVANCE OF A CLOSED LOW CURRENTLY OVER SW IOWA. REGIONAL RADAR MOSAIC SHOWED A SOLID AREA OF RAIN SHOWERS ADVANCING TO THE EAST ACROSS SOUTHERN ILLINOIS AND MOVG INTO SW INDIANA. THE ACTIVITY TRAILED OFF TO SCATTERED LIGHT SHOWERS IN SE MISSOURI AND WEST KENTUCKY. WE EXPECT CLOUDS TO CONTINUE TO INCREASE FROM WEST TO EAST ACROSS THE REGION THIS AFTERNOON...WITH THE CHANCE OF RAIN INCREASING AS WELL. WILL HAVE HIGHEST POPS ACROSS SOUTHERN INDIANA INTO ADJACENT NORTHERN KENTUCKY...AND LOWER POPS ACROSS SOUTH CENTRAL KENTUCKY BASED ON THE LATEST TRENDS AND RUC/GFS MODEL SUGGESTIONS. STABILITY PARAMETERS SUGGEST LITTLE CHANCE OF THUNDER. THE MODELS MOVE THE UPPER LOW AND SFC REFLECTION INTO CNTRL INDIANA BY 12Z TUESDAY...SO WILL HOLD ONTO A CHANCE OF SHOWERS ALL NIGHT. WILL THEN END THE CHANCE FROM WEST TO EAST EARLY TUESDAY AS THE LOW MOVES EAST TO THE MID ATLANTIC REGION. CLOUDS WILL BE MORE PREVALENT THAN NOT THROUGH TUESDAY...IN RELATION TO THIS SYSTEM. AS FAR AS TEMP GUIDANCE...USED A BLEND OF GOING NUMBERS AND THE LATEST GFS MOS. QUIET WEATHER IS EXPECTED TUE NIGHT THROUGH WEDNESDAY AS HIGH PRESSURE TAKES CONTROL. AFTER WEDNESDAY...THINGS ARE NOT AS CLEAR CUT. WE WILL BE IN RETURN FLOW ACROSS THE FA...WITH THE UPPER LEVEL FLOW PATTERN MORE ACTIVE AND SOUTHWESTERLY. FOR NOW...HAVE ELECTED TO KEEP IT DRY THROUGH WEDNESDAY NIGHT...AND ONLY INTRODUCE LOW CHANCE POPS FOR THURSDAY. THE MORE CLEAR CUT SIGNAL IN THE MODELS IS TOWARD DAY BREAK FRIDAY...AS A FRONTAL SYSTEM MOVES INTO WEST SECTIONS OF THE FORECAST AREA. SO...AFTER TODAY...OUR HIGHEST POP EVENT WILL BE FRIDAY...AS A FRONT IS FORECAST TO MOVE ACROSS THE REGION FROM WEST TO EAST...OFFERING UP A CHANCE OF SHOWERS AND THUNDERSTORMS. WILL LINGER A LOW CHANCE OF SHOWERS IN FOR FRIDAY NIGHT...THEN KEEP CONDITIONS MAINLY DRY FROM SATURDAY ON...PER THE LATEST GFS AND HPC GUIDANCE. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ NOLES ky AREA FORECAST DISCUSSION...AVIATION UPDATE NATIONAL WEATHER SERVICE SPRINGFIELD MO 1207 PM CST MON MAR 27 2006 .DISCUSSION... STRATUS DECK HAS BECOME SCATTERED OVER THE WESTERN PORTIONS OF THE AREA AND TEMPERATURES HAVE RESPONDED. INSOLATION HAS LED TO TEMPS IN THE LOWER/MIDDLE 60S WHERE CLEARING HAS OCCURRED...WHILE UNDER THE CLOUDS TEMPS ARE HOLDING IN THE 40S AND 50S. WILL ISSUE AN UPDATE TO BUMP HIGHS UP OVER THE CENTRAL AND WESTERN ZONES FOR THIS AFTERNOON. JLT/GAGAN && .PREV DISCUSSION... VIGOROUS UPPER DISTURBANCE CURRENTLY TRACKING EASTWARD THIS MORNING ACROSS NEBRASKA. IN RESPONSE TO THIS FEATURE...AN AREA OF SHOWERS WITH EMBEDDED THUNDERSTORMS DEVELOPED ACROSS EASTERN KANSAS AND PUSHED INTO MISSOURI. THIS PRECIPITATION WAS FUELED BY MODEST MOISTURE TRANSPORT/CONVERGENCE ON THE NOSE OF A 55-60 KT LOW LEVEL JET AT 850 MB. IN ADDITION...UPPER DIFFLUENCE AT 250 MB WAS NOTED ON THE REGIONAL PROFILER NETWORK AS THIS AREA WAS IN THE LEFT FRONT QUAD OF THE UPPER JET. AT THE SURFACE...LOW PRESSURE WAS ALSO CENTERED OVER NEBRASKA WITH ITS ASSOCIATED COLD FRONT STRETCHING SOUTHWARD ACROSS CENTRAL KANSAS. PRIMARY SHORT TERM FORECAST CONCERNS WILL BE RAIN CHANCES AND TEMPERATURES. HELD ON TO LIKELY POPS FOR THE MORNING HOURS MAINLY EAST OF HIGHWAY 65..AS THIS AREA WILL STILL BE UNDER THE INFLUENCE OF INCREASING MOISTURE TRANSPORT AND 925-850MB THETA-E ADVECTION AHEAD OF THE APPROACHING COLD FRONT. FURTHER TO THE WEST...TRENDED POPS DOWNWARD TO LOW END CHANCES ALONG THE KANSAS BORDER AS THE RUC SHOWS DRIER AIR ADVECTING IN FROM THE WEST SHORTLY AFTER 12Z. ANY PRECIPITATION TODAY WILL BE SHOWERY IN NATURE WITH ONLY AN ISOLATED THUNDERSTORM POSSIBLE. THE NAM SHOWS SOME WEAK ELEVATED INSTABILITY WITH LI VALUES LIFTED FROM 800 MB AROUND -1 THROUGH 18Z. AS FOR TEMPERATURES...WITH DRIER AIR ADVECTING IN FROM THE WEST...AREAS ALONG THE KANSAS BORDER SHOULD SEE ENOUGH SUNSHINE TODAY TO REBOUND INTO THE LOWER 60S. WILL HAVE TO WATCH TEMPS MORE CLOSELY FURTHER EAST. FOR NOW BANKING ON CLOUD COVER HANGING ON FOR MUCH OF THE AFTERNOON WHICH WOULD LIKELY KEEP HIGHS ONLY IN THE LOW/MID 50S. TUESDAY LOOKS LIKE A TRANQUIL DAY WITH TEMPERATURES NEAR LATE MARCH NORMALS AS UPPER RIDGING TAKES HOLD IN THE WAKE OF TODAY'S SYSTEM. BY WEDNESDAY...SOUTHERLY FLOW RETURNS TO THE AREA WHICH WILL LIKELY ALLOW HIGHS TO CLIMB TO NEAR 70 ACROSS SOUTHEAST KANSAS AND MUCH OF SOUTHWEST MISSOURI. HAVE SOME SLIGHT AND LOW POPS WEDNESDAY INTO WEDNESDAY AS MOISTURE BEGINS TO RETURN NORTHWARD AHEAD OF THE NEXT UPPER SYSTEM. THE BULK OF THE LOW-LEVEL MOISTURE TRANSPORT FIELDS KEEP THE BETTER CONVERGENCE TO THE WEST...SO HIGH POPS WEREN'T WARRANTED FOR THIS PERIOD. STILL SOME MODEL DIFFERENCES REGARDING THE UPPER SYSTEM ENTERING THE PLAINS BY THURSDAY AFTERNOON. ONE THING FOR CERTAIN IS THAT THE SYSTEM WILL HAVE PLENTY OF MOISTURE TO WORK WITH. THE LATEST ECMWF TAKES THE UPPER LOW ACROSS NEBRASKA TOWARD THE UPPER MISSISSIPPI VALLEY...WHILE THE GFS TRACKS THE SYSTEM ACROSS KANSAS AND NORTHERN MISSOURI. THE GFS SOLUTION WOULD BRING A GOOD SHOT OF SEVERE WEATHER TO THE OZARKS REGION...AS 0-6KM BULK SHEAR VALUES INCREASE TO AROUND 60KTS BY 00Z FRIDAY. SAW && .AVIATION... FOR THE 18Z TAFS...CONDITIONS ACROSS THE TAF SITES SHOULD REMAIN VFR THROUGH THE EVENING WITH A DROP TO MVFR AFTER MIDNIGHT. LOW LEVEL MOISTURE WILL BRING A STRATOCUMULUS DECK INTO THE OZARKS WITH CEILINGS AROUND 1500 TO 2000 FT. THIS CEILING SHOULD PERSIST INTO THE DAY ON WEDNESDAY WITH A HIGH CIRRUS DECK KEEPING THE SUN FROM BURNING THE STRATUS OFF AS THE DAY PROGRESSES. HATCH && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. $$ WFO SGF mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC 219 PM EST MON MAR 27 2006 .SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...SFC AND UPR LVL RDG JUST W OF CWA TDY. SLO EWD DRIFT WL KP DRY NNW FLO OVR CWA INTO THIS EVE. 5H FLO TO BCM QUASI ZNL LTR TNGT AS WK TROF APPCHS FRM THE W. ASSCTD SFC FNT WL TURN LO LVL FLO TO SW BY MDNGT TNGT. NAM A LTL FASTER THAN RUC IN TURNG LO LVL FLO ARND. WL LEAN TWRD RUC TIMING. GIVEN THIS WND SHIFT XPCT LO TEMPS TO OCCUR BFR MIDNGT AND WL HV HRLY TEMPS REFLECT THIS. SNDGS NOT SHOWG TOO MUCH DECPLG OF THE WNDS. THEY DO SHOW A SHALLOW INVERSION...AT THE SAME TM AS SUM MID LVL MSTR. THRFR AM NOT XPCTG F TO BE A PROBL TNGT. CLDS WL STRT INCRSG MIDDAY TUE. OMEGA NOT OVRLY IMPRSV WI THIS SYS. LO LVL INITIALLY SUMWHAT DRY SO WL HOLD OFF ON POPS TIL JUST BFR SS. NOT XPCTG TOO MUCH OVRNGT BUT WL CARRY 20 TO 30 POPS...ENDING BFR SR WED. && .LONG TERM (WEDNESDAY THROUGH MONDAY)...AFT THIS SYS MVS OUT HI PRES WL DOMINATE THE WX THRU THU. MSTR WL STRT INCRSG THU NGT BUT SFC SYS DOESNT REALLY MV THRU TIL LT SAT. WL CONT CRRNT FCST OF SLGT CHC. GFS SHOWG COLD SURGE TO MV THRU SUN AFTN...BHND FNT. && .AVIATION...VFR CONDITIONS WILL PREVAIL ACROSS THE REGION...UNDER MOSTLY CLEAR SKIES...IN THE PREDOMINATELY DRY AIRMASS. INCREASE MID-LEVEL CLOUDINESS IS EXPECTED LATE TONIGHT...WHICH SHOULD HNDER THE FORMATION OF RESTRICTING VISIBILITIES IN FOG. && .MARINE...NE BACKSWELL FROM A POWERFUL BUT DISTANT ATLC LOW CONTINUES OVER THE WATERS. 41025 HAS BEEN AT 5 FT SINCE PAST 24 HOURS BUT THE DUCK COE HAS BEEN 6 FT ALL DAY. THEREFORE THE SCA FOR SEAS WILL BE CONTINUED THROUGH THIS EVENING AS WAVEWATCH III KEEPS SEAS NORTH OF OCRACOKE AROUND 6 FT. EXCEPT SWELL TO DIMINISH AND SEAS TO DROP BLO SCA CRITERIA BY TUE MORNING. A COLD FRONT WILL APPROACH THE WATERS LATE TUE AND CROSS THE AREA EARLY WED. SW WINDS ON TUE WILL SHIFT TO THE NW WITH FRONTAL PASSAGE. WINDS SPEEDS ARE EXPECTED TO REMAIN AT OR BLO 20 KTS. HIGH PRES WILL BUILD OVER THE STATE LATE WED THROUGH THU BEFORE MOVING OFFSHORE THU NIGHT. ANOTHER FRONTAL SYSTEM WILL APPROACH THE MARINE AREA ON SAT THEN MOVING OFFSHORE EARLY SUN. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY FOR AMZ150-152-154 UNTIL 4 AM TUESDAY. && $$ SHORT TERM...GOODALL LONG TERM...GOODALL AVIATION...PRINGLE MARINE...PRINGLE nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 1052 AM CST MON MAR 27 2006 .UPDATE...BASED ON CURRENT RADAR TRENDS...AS WELL AS LATEST RUC AND NAM MODEL...NUDGED HIGHER PRECIPITATION PROBABILITIES A BIT FURTHER NORTHWARD FOR THIS AFTERNOON. WITH RESPECT TO PRECIPITATION TYPE...OBSERVATIONS STILL INDICATED SNOW AND RAIN IN SOUTHEAST MN AS OF 1630Z. FORECAST SOUNDINGS SUPPORT ALL RAIN IN THIS AREA DURING THE AFTERNOON...SO HAVE CONTINUED TREND TOWARD ALL RAIN AS IN CURRENT FORECAST FOR SITES SUCH AS KRST...KTOB...KAUM. OTHER CHANGES MADE WERE TO LOWER TEMPERATURES IN PORTIONS OF NORTHEAST IOWA AND SOUTHEAST MN...WHERE PRECIPITATION HAS KEPT TEMPERATURES FROM RISING TOO MUCH. UPDATED DATA BASE WITH AFOREMENTIONED CHANGES. UPDATED ZONE FORECAST PRODUCT SHOULD BE ISSUED BY 1700Z. && THOMPSON .PREV DISCUSSION... SHORT TERM...THROUGH WEDNESDAY MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES AND TYPES FOR TODAY AND TONIGHT. SURFACE ANALYSIS THIS MORNING SHOWS HIGH PRESSURE EXTENDING FROM THE NORTHERN GREAT LAKES SOUTH INTO THE OHIO RIVER VALLEY. LOW PRESSURE WAS OVER CENTRAL SOUTH DAKOTA NEAR K9V9. COLD FRONT EXTENDED SOUTH FROM THE LOW INTO KANSAS. REGIONAL RADARS AND SURFACE OBS INDICATE LIGHT RAIN AS DEVELOP AHEAD OF THE SYSTEM FROM NORTHWEST MISSOURI INTO WESTERN MINNESOTA. 00Z MODELS HAVE CONTINUED THE TREND OF PREVIOUS MODEL RUNS OF SHIFTING THIS SYSTEM FARTHER SOUTH. NO CLEAR CUT MODEL FAVORITE THIS MORNING AS THE NAM AGAIN HAD SOME INITIALIZATION PROBLEMS WITH THIS SYSTEM WHILE THE GFS HAD TOO MUCH QPF AT 06Z COMPARED TO RADARS/OBSERVATIONS. HAVE TRIED TO TAKE A BLEND APPROACH. BOTH MODELS NOW SHOW THE BEST FORCING TO AFFECT MAINLY THE SOUTHERN SECTIONS OF THE FORECAST AREA AND QUICKLY TAPER OFF TO THE NORTH. THE BEST PV ADVECTION IN THE 500-300 MB LAYER NOW SLIDES ACROSS IOWA AND MISSOURI WITH THE ONLY ABOUT 4-6 PVU/S COMING ACROSS NORTHERN IOWA AND SOUTHERN WISCONSIN. WITH THE UPPER LEVEL LOW EXPECTED TO MOVE ACROSS IOWA...THE AGEOSTROPHIC FLOW FROM THE EXIT REGION OF THE 300 MB JET WILL STAY WELL TO THE SOUTH AS WELL. DEEP BUT WEAK QG CONVERGENCE STILL EXPECTED TO MOVE ACROSS THE SOUTHERN SECTIONS TODAY THROUGH THIS EVENING. THE BEST FRONTOGENESIS WILL BE SOUTH OF THE AREA...BUT THE GFS DOES SHOW A SECONDARY BAND DEVELOPING THIS AFTERNOON ACROSS SOUTHERN WISCONSIN IN THE 850-500 MB LAYER. TIME/HEIGHT CROSS SECTIONS DO SHOW THE FORCING THAT COMES THROUGH SHOULD BE ENOUGH TO PRODUCE ABOUT 5 MICROBARS/S OF VERTICAL MOTION AND WITH DEEP MOISTURE IN PLACE...EXPECT THAT LOCATIONS SOUTH OF THE MINNESOTA BORDER WILL SEE THE PRECIPITATION AND HAVE CONTINUED THE CATEGORICAL POPS THERE. QUICKLY TAPERED OFF THE POPS TO THE NORTH WITH THE DECREASE IN THE FORCING AND ONLY BROUGHT IN A SLIGHT CHANCE FOR THE FAR NORTH THIS AFTERNOON. MODEL SOUNDINGS FROM THE NAM INDICATE THIS SHOULD BE AN ALL LIQUID EVENT...BUT THE GFS SHOWS ENOUGH DYNAMICAL AND EVAPORATIVE COOLING EARLY THIS MORNING FOR THE POSSIBILITY OF A RAIN/SNOW MIX. HAVE LEFT THIS IN FOR A SHORT WHILE THIS MORNING BEFORE SWITCHING OVER TO ALL RAIN. INCLUDED SOME LIKELY POPS ACROSS THE SOUTHEAST SECTIONS FOR THIS EVENING BEFORE GOING DOWN TO CHANCE AFTER 03Z. GRADUAL COOLING OF THE COLUMN BEHIND THE SYSTEM SHOULD ALLOW FOR THE RAIN TO MIX WITH SNOW AND POSSIBLY CHANGE TO ALL SNOW FOR THE WESTERN SECTIONS AFTER 06Z IF THERE IS STILL ANY LINGERING PRECIPITATION IN THE AREA. HIGH PRESSURE THEN COMES ACROSS FOR TUESDAY AND TUESDAY NIGHT. THIS SLIPS OFF THE EAST WEDNESDAY AHEAD OF THE NEXT SYSTEM. SOUTH WINDS AND WARM AIR ADVECTION ON THE BACK SIDE OF THE HIGH SHOULD PUSH TEMPERATURES INTO THE 50S. LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY WARM AIR ADVECTION WILL CONTINUE INTO WEDNESDAY NIGHT WITH THE GFS SHOWING A GOOD MOISTURE TRANSPORT SIGNAL IN THE AREA. AIRMASS WILL INITIALLY BE DRY...BUT BELIEVE THE MOISTURE TRANSPORT WILL ALLOW SATURATION TO OCCUR LATE WEDNESDAY NIGHT. THE WARM AIR ADVECTION RESULTS IN ABOUT 2 MICROBARS/S OF UPGLIDE ON THE 285K ISENTROPIC SURFACE AND THIS MAY BE ENOUGH TO SUPPORT SOME LATE NIGHT SHOWER DEVELOPMENT. MAINTAINED THE LOW CHANCE POPS ACROSS THE WEST FOR THIS POSSIBILITY. THIS SYSTEM THEN WILL COME ACROSS THE REGION THURSDAY NIGHT AND FRIDAY. STILL SOME MODEL DIFFERENCES IN THE TRACK OF THE SURFACE LOW WITH THE GFS TAKING THE LOW FROM CENTRAL KANSAS AT 00Z FRIDAY TO EASTERN WISCONSIN BY 00Z SATURDAY. THE ECMWF IS FARTHER NORTH WITH THE TRACK FROM SOUTH DAKOTA TO LAKE SUPERIOR. WITH THE DIFFERENCES IN THE MODELS...LEFT THE EXTENDED PORTION OF THE FORECAST ALONE AND WILL LET THE DAY SHIFT MAKE ANY CHANGES AFTER LOOKING AT THE GFS ENSEMBLES. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ 04 wi