AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 845 PM EST WED MAR 8 2000 MAIN CONCERN OVERNIGHT IS FOG. METARS OVER WRN FL PANHANDLE ALREADY SHOWING REDUCED VISIBILITIES DUE TO A COMBINATION OF HAZE AND MIST. ETA...NGM...AND 23Z RUC CORRESPONDINGLY FORECAST LOWEST SATURATION PRESSURE DEFICITS THURSDAY MORNING OVER OUR WESTERN ZONES. THIS IS LIKELY ASSOCIATED WITH WEAK ONSHORE MOISTURE TRANSPORT AROUND THE BROAD SURFACE HIGH CENTERED OFF THE EAST COAST OF FL. ALTHOUGH DRIER CONTINENTAL AIR SHOULD REMAIN OVER OUR ERN ZONES...SMOKE FROM FIRES N OF CROSS CITY AND SW OF VALDOSTA MAY LOCALLY ENHANCE FOG POTENTIAL. METARS AT VLD AND VAD ALREADY REFLECT THIS. AT THIS TIME...WILL KEEP PATCHY FOG WORDING INTACT IN ZONES. DENSE FOG THREAT IN ERN ZONES SHOULD BE ISOLATED AND BEST HANDLED WITH NOWCASTS. ONLY MINOR WIND ADJUSTMENTS PLANNED FOR COASTAL WATERS FORECASTS. INPUT IS ALWAYS WELCOME. .TLH... AL...NONE. GA...NONE. FL...NONE. TJT fl AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE GOODLAND 933 PM MST WED MAR 8 2000 LATEST SATL SHOWG STRATUS DVLPG OVR NW OF CWFA. LATEST RUC LOOKS TO HAVE THE BEST HANDLE ON IT RIGHT NOW. IT EXPANDS THE AREA TO COVER MOST OF THE WRN HALF OF THE CWFA BY 12Z...AND MAYBE A LTL INTO ERN CWFA. SO WL CHANGE WRN HALF TO CLDY OR BCMG CLDY. BECAUSE OF THAT WL HAVE TO CHANGE WORDG IN 2ND PERIOD OF ZONES. .GLD...NONE. BULLER ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND 754 PM MST WED MAR 8 2000 LATEST SFC OBS/ANALYSIS AND PROFILERS HAVE WINDS BLO ADVISORY CRITERIA NOW WITH DECREASING TREND EXPECTED TO CONT AS SFC RDG PUSHES IN AND NRN PLAINS SYSTEM LIFTS OUT. THEREFORE WL CANCEL WND ADVISORY. COMPARING LATEST RUC/ETA TO CURRENT OBS/AREA PROFILERS...WL BE TAKING WND SPEEDS DOWN A LITTLE MORE IN NRN AND ERN SECTIONS. BECAUSE OF THAT...WL LWR MINS TO NR 25. REST OF FCST ON TRACK. .GLD...NONE. BULLER ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PADUCAH KY 245 PM CST WED MAR 8 2000 LATEST LAPS PLAN VIEW MSTR/INSTABILITY PLOTS STILL HINTING AT POTENTIAL FOR SIGNIFICANT CONVECTION LATER THIS AFTERNOON ACRS EXTREME SERN MO...INTO SRN IL...WRN KY AND SWRN IN. MAIN INHIBITING FACTOR ATTM IS CAPPING LAYER ACRS CWA AND DRIER MID-LVL AIR MOVING IN FROM WRN MO. THIS FACTOR MAY BE MINIMIZED AS INSOLATION FROM SUN DIMINISHES AND MAIN LIFT DEVELOPS JUST OFF THE SFC...TAKING ADVANTAGE OF GOOD THETA-E ADVECTION AND SHEAR ABOVE THE PBL. GIVEN THE UNCERTAINTY OF THE ACTUAL POINT OF CONVECTIVE INITIATION... DECIDED TO MENTION INCRSING NUMERICAL POPS FROM WEST TO EAST ACRS FORECAST AREA. IF CAPPING AND DRY AIR TOO GREAT...EVENING SHIFT MAY HAVE TO DROP OR SEVERELY CURTAIL EVENING AND OVERNIGHT POPS. ALTHOUGH A SLIGHTLY FAST AND TOO FAR NORTHEAST WITH UPPER LOW...AVN APPEARED TO HANDLE THE MAIN TRACK OF THE TIGHT LOW IN THE UPPER MIDWEST WELL. AVN WAS DEFINATELY SUPERIOR IN SFC DEWPOINT ANALYSIS OVER ETA/NGM...AND EVEN THE RUC AT 18Z TODAY. UTILIZED AVN LOW LEVEL INSTABILITY AND MSTR PROGS FOR PCPN FCST TONIGHT. ALTHOUGH SLOW TO MOVE SEWD TONIGHT AND EARLY THU...MAIN FRONTAL BOUNDARY SHOULD MOVE WELL INTO AR/MS/TN...BEFORE NEXT SYSTEM MOVES IN FROM THE WRN U.S. GOOD ISENTROPIC LIFT ACRS SFC BOUNDARY LATE THU INTO FRI. FCST ADJUSTED TO INCREASE CLOUDS FROM THE WEST...AS WELL AS THE MENTION OF STABLE PCPN FROM WEST TO EAST INTO FORECAST AREA. USED A COMPROMISE OF AVN/MRF POSITION OF NEXT 50H LOW FURTHER NORTH...CLOSER TO A KJLN-KSTL LINE. THIS SHOULD KEEP TEMPS SLIGHTLY WARMER INTO SAT AND AM NOT CONCERNED ABOUT PCPN TYPE AT THIS TIME FOR SRN IL AND SERN MO...BELIEVE IT SHOULD REMAIN AS RAIN. ADDED MENTION OF TSRA FOR SRN ZONES FRIDAY NIGHT...BUT BELIEVE HIGHEST PROBABILITY OF ELEVATED AND/OR SFC TSRA WILL BE DURING THE EVENING. STABLE...STRATIFORM RAIN SHOULD BE THE RULE ON SAT. SHARP RIDGE MOVES IN ON SUN...CLEARING OUT MOST OF THE CWA. A WEAK NORTHWEST FLOW SYSTEM MOVES DOWN ON MONDAY AND IS PROGGED TO CLIP THE ERN END OF THE FORECAST AREA. DECIDED TO MENTION A CHANCE OF RAIN AT THIS TIME FOR ERN ZONES ON MON. LEANED TOWARD FAN GUIDANCE FOR MAX/MINS IN SHORT TERM. ALTHOUGH WINDS COULD GUST TO 30+ MPH LATE THIS AFTN AND EVENING WITH DRYLINE/FRONT...WL NOT USE ANY SPECIAL WORDING OR ADVISORIES IN FIRST PD. WL LEAVE TO SHORT TERM FORECASTS FOR ANY SIGNIFICANT WINDS. .PAH...NONE. SMITH ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON MS 930 PM CST WED MAR 8 2000 ONCE AGAIN THE CHANCE OF RAIN HAS PASSED US BY ACROSS THE FORECAST AREA FOR TONIGHT. THE 12Z AVN MODEL WAS AGAIN TOO OPTIMISTIC ON CHANCE OF RAIN FOR THE NORTHERN HALF OF THE FORECAST AREA. THE SHOWERS THAT WERE OCCURRING IN NORTHWESTERN LOUISIANA EARLY THIS EVENING HAVE DISSIPATED AND THE LATEST RUN OF THE RUC MODEL IS PREDICTING NO RAIN FOR TONIGHT FOR THE FORECAST AREA. I CHANGED WORDING IN MOST ZONES FROM MOSTLY CLOUDY TO PARTLY CLOUDY. ALSO MADE MINOR CHANGES TO WINDS AND TEMPERATURES IN SEVERAL ZONES AND CORRECTED WORDING FOR SATURDAY FORECASTS. .JAN... MS...NONE. AR...NONE. LA...NONE. 15 ms AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 230 PM CST WED MAR 8 2000 IN SHORT TERM...WILL EXTEND WIND ADVISORY INTO EVENING AS PROFILERS ARE SHOWING A STRONG UNIDIRECTIONAL PROFILE. RUC ALSO SHOWING 45 KTS OF WIND CONTINUING THROUGH 06Z AT 925 MB. THINK WINDS WILL FALL BACK UNDER CRITERIA AFTER SUNSET AS ATMOSPHERE DECOUPLES. OTHERWISE...WILL LOOK AT PLACEMENT OF DRYLINE NEAR ZONE TIME AND PLACE CONTINUED CHC OF EVENING TSRA TO THE EAST OF IT. MSAS NOW SHOWING -4 TO -7 LI'S OVER IL WITH UPPER JET STREAK APPROACHING AREA. MODELS ALL SEEMED TO BE VERIFYING PRETTY WELL AT 18Z WITH THE ETA DOING THE BEST. DON'T SEE TOO MANY SIGNIFICANT DIFFERENCES THROUGH THE RUN. UPPER LOW OVER ERN NEB WL MOVE RAPIDLY ENE. 1000-850 MB RELATIVE HUMIDITY PROGS INDICATE LOW CLOUDS OVER NEB AND MN WL MOVE SEWD INTO WRN AND NRN PARTS OF CWFA OVERNIGHT AND BE ALONG AND N OF I-70 ON THURSDAY. BEST INSTABILITY WITH UPPER LOW SHIFTS NEWD...SO WL KEEP OUT MENTION OF PRECIP ON THURSDAY. TROF NOW OFF W COAST WILL MOVE EWD AND BEGIN TO AMPLIFY AS IT APPROACHES THE MIDDLE MS VALLEY ON FRIDAY. AVN'S UVV...UPPER DIVERGENCE AND FRONTOGENTICAL FORCING INCREASES ON FRIDAY AFTERNOON...MAINLY TO THE S AND W OF STL. BEST COLD AIR ADVECTION WILL START UP ON THURSDAY AFTERNOON AS WINDS SWITCH OUT OF THE NW...SO WILL GO WITH THE COOLER FWC. QUITE A GAP WITH FWC/FAN TEMPS ON FRIDAY. DON'T LIKE WARM FAN TEMPS WITH NE WINDS AND CLOUDS ON FRIDAY...BUT FWC LOOKS TOO COOL. WILL GO WITH A COMPROMISE. INTO THE EXTENDED...THE MRF...NOGAPS...ECMWF AND NEW AVN HAVE COME TOGETHER IN REASONABLE AGREEMENT WITH THE NEXT SHORWAVE TROF MOVING THRU THE MID MS VALLEY ON SATURDAY. SEF HAS A DEEPER AMPLITUDE TROF AND CONSEQUENTLY SLOWS THE TROF DOWN...BUT PREFER THE MORE PROGRESSIVE SOLUTION. WILL CONTINUE TO CARRY PRECIP ASSOCIATED WITH THE TROF FOR SATURDAY. CRITICAL THICKNESSES STILL SHOWING A POTENTIAL FOR SNOW FRIDAY NITE INTO SATURDAY BEFORE THE PRECIP ENDS. MRF IS SHOWING ANOTHER VORT MOVING IN FROM NW SUN NIGHT INTO MONDAY...BUT IT IS KEEPING MOST OF THE PRECIP JUST N AND E OF CWFA SO WILL LEAVE DRY FOR NOW. .STL...WIND ADVISORY FOR CNTRL AND ERN MO AND PARTS OF SW IL FOR THIS EVENING. BRITT mo SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 900 AM MST WED MAR 8 2000 ...WILL UPDATE ZONES AND STATE... VORTICITY ASSOCIATED WITH UPPER LEVEL LOW THAT WAS OVER SE ID TUESDAY APPEARS TO HAVE TAKEN A MORE NORTHERLY TRACK THAN WAS PROGGED YESTERDAY. RUC AND NEWEST ETA DRIFT VORT MAX OVER CENTRAL MT THROUGH THE DAY TODAY. AT THE SURFACE UPSLOPE GRADS CONTINUE THROUGH THE DAY...AND THERE IS PLENTY OF MOISTURE TO WORK WITH. EXPECT THAT SNOW WILL CONTINUE THROUGH THE DAY OVER CENTRAL MONTANA...TAPERING OFF FROM THE SOUTH AS PVA ENDS. WILL EXTEND SNOW ADVISORY THROUGH THIS AFTERNOON FOR MOST LOCATIONS. HAVE RECEIVED REPORTS OF UP TO 4 INCHES SNOW NEAR DILLON BUT SATELLITE LOOP INDICATES THAT SNOW SHOULD BE TAPERING OFF TO SHOWERS THIS AFTERNOON. WILL UPDATE TO PUSH BACK ENDING OF SNOW...UPDATE POPS AND SNOW ADVISORY. TEMPS LOOK OK. HAD SOME CONCERN THAT MAX IN SW MT ZONES TOO HIGH...BUT BREAKS IN CLOUDS SHOULD ALLOW WARMING SUCH AS OCCURRED AT KIDA THIS LAST HOUR. MPJ GTF +44 HLN +33 HVR 422 mt AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE NORMAN OK 950 PM CST WED MAR 8 2000 COLD FRONT HAS REACHED CENTRAL AND SOUTHWEST OKLAHOMA DURING THE EVENING HOURS. TIMING OF CURRENT FORECAST LOOKS REASONABLE WITH LATEST RUC INDICATING THE FRONT WILL MOVE SOUTH OF THE RED RIVER AND INTO WESTERN NORTH TEXAS BY MORNING. CURRENT LOW TEMPS FOR THURSDAY MORNING MAY BE TOO LOW IF WINDS STAY UP THROUGH THE NIGHT... HOWEVER DECOUPLING COMBINED WITH GRADUALLY WEAKENING GRADIENT STILL LOOKS POSSIBLE LATER TONIGHT. 32 .OUN... OK...NONE. TX...NONE. ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MEMPHIS TN 840 PM CST WED MAR 8 2000 WILL UPDATE FORECAST TO REMOVE POPS FOR THE REMAINDER OF TONIGHT. RADAR MOSAIC NOT INDICATING ANY PRECIPITATION. WITH LOSS OF DAYTIME HEATING AND UPPER LEVEL SUPPORT NOW TO THE NORTH...DO NOT EXPECT ANY MORE THAN AN ISOLATED SHOWER OR THUNDERSTORM AT BEST TONIGHT. SURFACE FRONT FROM ABOUT WEST PLAINS MO TO HOT SPRINGS AR TO TEXARKANA AR. DEWPOINTS IN THE 60S DIRECTLY AHEAD OF THE FRONT DROP QUICKLY TO THE 30S BEHIND THE FRONT. LATEST RUC MODEL FORECAST FRONT ONLY INTO NORTHEAST AR BY 12Z..THUS MAY NEED TO RAISE MINIMUM TEMPERATURE FORECASTS IN SOME ZONES. WILL WORD FORECAST AS PARTLY CLOUDY FOR THE REMAINDER OF TONIGHT AS A VARIETY OF CLOUDS CONTINUE TO FLOW INTO THE AREA FROM THE SOUTHWEST. .MEM...NONE. tn SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO 255 AM MST THU MAR 9 2000 MAIN MESSAGE SHORT TERM WILL BE COOLER TEMPERATURES WITH A CHANCE OF PRECIPITATION THROUGH FRIDAY WITH A DRYING AND WARMING TREND IN THE OFFING FOR THE WEEKEND. CWFA CURRENTLY EXPERIENCING VARIABLE CLOUDS WITH SOME LOW CLOUDS MOVING INTO PORTIONS OF THE EASTERN ZONES AS NOTED BY LATEST SATELLITE IMAGES AND SURFACE OBSERVATIONS. LATEST RUC MODEL SUGGESTS THAT LOW CLOUDS AND AREAS OF FOG TO CONTINUE OVER PORTIONS OF THE EASTERN PLAINS INTO MID-MORNING... THEN THESE CONDITIONS SHOULD IMPROVE...WILL WORD ACCORDINGLY IN ZONE PACKAGE. LATEST ETA/AVN MODELS INDICATE THAT SEVERAL UPPER DISTURBANCES TO ROTATE ACROSS CWFA TODAY INTO FRIDAY AND WILL CONTINUE WITH RELATIVELY LOW POPS FROM INHERITED FORECAST. HIGHER POPS WILL BE OVER ZONES 58/59/60 AND 61 WITH LATEST SNOW MODEL AND CROSS SECTIONS SUPPORTING A FEW INCHES OF SNOW. 700 MB TEMPERATURES PROGGED TO DROP TODAY INTO FRIDAY WITH MAXIMUM TEMPERATURES TODAY SOME 7F TO 9F COOLER THAN NOTED WEDNESDAY WITH FRIDAY'S MAXIMUM TEMPERATURES AN ADDITIONAL 3F TO 7F COOLER. WINDS EXPECTED TO REMAIN WELL BEHAVED. IN THE LONGER TERM...SATURDAY INTO MONDAY...AVN AND MRF INDICATE UPPER RIDGING/NORTHWEST FLOW ALOFT IN CONTROL SATURDAY AND SUNDAY WITH MINIMAL LIFT AND THEN MRF INDICATES A WEAK DISTURBANCE PUSHING ACROSS MAINLY NORTHERN SECTIONS ON MONDAY...HOWEVER FOR NOW WILL KEEP DRY FORECAST GOING ALONG WITH WARMING TREND SATURDAY INTO MONDAY. .PUB...NONE. co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 940 PM EST WED MAR 8 2000 APX 88D SHOWING SCATTERED SHOWERS AND THUNDERSTORMS OVER EAST UPPER AND NORTHERN LOWER MICHIGAN. THE MAIN CONCENTRATION OF SHOWERS AND THUNDERSTORMS IS CURRENTLY OVER LAKE MICHIGAN AND NORTHWEST LOWER. SURFACE REPORTS FROM AROUND EAST UPPER AND NORTHWEST LOWER MICHIGAN SHOW THAT THE THUNDERSTORMS ARE GENERALLY DUMPING HEAVY RAIN AND SMALL HAIL UNDER ONE QUARTER INCH. THIS AREA OF SHOWERS AND THUNDERSTORMS IS BEING FUELED BY STRONG 700/500 MB DPVA IN ADVANCE OF A VORT MAX MOVING OVER WISCONSIN. THE LATEST RUC AND MESO ETA SHOWS 700/500 MB DPVA AFFECTING THE FORECAST AREA THRU THE OVERNIGHT HOURS WITH 850 DEW PTS INCREASING TO 6C TO 8C. GRB LATEST 88D SHOWS AN AREA OF SHOWERS AND THUNDERSTORMS STILL AFFECTING EAST WISCONSIN AND MUCH OF LAKE MICHIGAN. RUC AND MESO ETA MODEL SOUNDINGS SHOW LOW LEVEL TEMPERATURES PROFILES FOR NORTHERN LOWER MICHIGAN WITH AN AT LEAST 4000 FOOT LAYER OF WARM AIR EXTENDING UP FROM THE SURFACE THROUGH 12Z. HOWEVER OVER EAST UPPER MICHIGAN... THE DEPTH OF THE LOW LEVEL WARM LAYER DECREASES DRASTICALLY BETWEEN 09Z AND 12Z WHICH WILL ALLOW THE PRECIPITATION TO MIX WITH SLEET. THEREFORE WILL CONTINUE SCATTERED RAIN SHOWERS AND THUNDERSTORMS FOR ALL OF NORTHERN LOWER MICHIGAN OVERNIGHT. FOR EAST UPPER WILL KEEP THE WINTER WEATHER ADVISORY AN MENTION THE RAIN SHOWERS MIXING WITH OR CHANGING TO SLEET OVERNIGHT. .APX...WINTER WEATHER ADVISORY...OVERNIGHT AND THURSDAY...MIZ008-015. SWR mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 440 PM EST WED MAR 8 2000 FCST PROBLEMS ARE MANY AND VARIED THIS AFTERNOON RANGING FROM TSRA TO FZRA TO ACCUMULATING SNOW. FIRST THINGS FIRST...SHRA AND TSRA MOVING THROUGH THE CWA ATTM. THIS "ARM" WILL MOVE THROUGH THE AREA THIS EVENING...NONE OF THE TSRA IS EXPECTED TO BE SEVERE WITH THE LOSS OF DAYTIME HEATING AND DISTANCE FROM THE BETTER DYNAMICS FURTHER WEST. COLD FRONT DRAPED ACROSS THE WEST AS IWD...ONT AND CMX ALL IN THE UPPER 30S TO LOW 40S AS OF 21Z. EXPECT THE FRONT TO WORK ITS WAY ACROSS THE U.P. TONIGHT FROM NNW TO SSE. RAIN WILL AGAIN BREAK OUT ONCE AGAIN LATE IN THE EVENING AS A SECOND COMMA HEAD REACHES THE AREA OF FRONTOGENESIS OVER THE U.P. WENT WITH A ETA/AVN MIX FOR THE FORECAST WITH A LEAN TOWARD THE RUC FOR THE SHORT TERM. BELIEVE THE NGM IS IN ERROR CONCENTRATING THE AREA OF BEST LIFT TO THE NORTH OF THE OTHER 2 MODELS. USED 950MB 0 LINE ON THE RUC AND ETA FOR THE CHANGE OVER THE FZRA AND SLEET. IT CHANGES OVER AT CMX AROUND 03Z...06Z AT MQT AND NR 12Z ALONG THE LAKE MICHIGAN SHORE. THERE IS QUITE A BIT OF WARM AIR AROUND...HOWEVER THE ARCTIC AIR IS NOT FAR AWAY AND THE DYNAMICS OF THE SYSTEM IS QUITE IMPRESSIVE. AS IN MOST CASES...BELIEVE THAT THE COLDER AIR AND DYNAMICS WILL WIN...PERHAPS FASTER THAN THE MODELS PROJECT...ESPECIALLY FOR THE CHANGE OVER FROM SLEET TO SNOW. AS THE COLDER AIR WORKS IN AROUND MIDNIGHT...THE MODELS ALL SHOW VERY HEALTHY QG FORCING WITH OMEGA VALUES APPROACHING 10 MICROBARS/SEC. MOISTURE IS IN ABUNDANCE WITH 4-5 G/KG OVER THE U.P. TONIGHT AND EARLY TOMORROW. THIS WITH THE FACT THAT 700-500MB LAPSE RATES ARE AROUND 7.5C/KM MAKES ME CONCERNED ABOUT THE CONVECTIVE ELEMENT TO THE PRECIPITATION TONIGHT...PERHAPS NOT THUNDERSTORMS...BUT HEAVIER BURSTS FOR PRECIP TO CHANGE IT OVER TO SNOW EARLIER AND ADD TO ACCUMULATIONS. AS A GENERAL RULE 4-8 INCHES IS EXPECTED FROM A IWD-MQT LINE NORTH. 2-5 INCHES FROM THERE SOUTH AND 1-3 FOR MNM. COMPLICATING FACTORS INCLUDE THE STG NE WIND DEVELOPING TONIGHT. EXPECT THAT THE UPSLOPE COMBINED WITH THE LAKE ENHANCEMENT WILL DRASTICALLY INCREASE SNOWFALL AMOUNTS IN THE HILLS INLAND IN MQT-BAR COUNTIES. MENTIONED 4 INCHES ALONG THE LAKE WHERE THE MORE MILD LAKE WILL CUT DOWN ON ACCUMULATIONS... UP TO A FOOT IN THE HIGHER ELEVATIONS. AS FAR AS THE LAKE ENHANCEMENT GOES...THE INVERSION WILL BE STEEP AND LOW...HOWEVER THE DELTA T FROM 925MB TO THE LAKE WILL BE 11C BY 12Z...VERY STEEP LL INSTABILITY. BELIEVE THAT THIS WILL ADD MOISTURE AND LIFT TO THE LOW LEVELS ENHANCING THE SNOW. WINDS WILL GUST TO 40-45 MPH ALONG THE LAKE AND WILL COVER THAT ASPECT IN THE WARNING STATEMENT. WIND CHILLS MAY APPROACH ADVISORY CRITERIA LATE TOMORROW WITH THE STIFF NE WINDS AND COLDER TEMPS. THE WEATHER BECOMES QUIET THURSDAY NIGHT THROUGH SATURDAY AND ONLY WK MID-LEVEL DISTURBANCES MOVE THROUGH WITH LITTLE MORE THAN FLURRIES. DIDN'T STRAY FAR FROM GUIDANCE THROUGH THIS PERIOD. IN THE EXTENDED... AS THE STORM IN THE SOUTHEAST TURNS UP THE COAST...THE GREAT LAKES SHOULD STAY IN THE CANADIAN AIRMASS. TEMPS WILL AT OR SLIGHTLY BELOW NORMAL SUNDAY AND MONDAY. THE MRF SHOWS A SMALL BUT POTENT DISTURBANCE MOVING THROUGH IN THE NW FLOW LATE SUNDAY. EURO MODELS DAMPEN THIS SYSTEM OUT. SINCE CONTINUITY HAS SN IN FOR LATE SUNDAY...WILL KEEP IT BUT MENTION LIGHT. NEXT UL TROUGH MOVES INTO THE PAC NW BY LATE MONDAY. THIS IS PROGGED TO MOVE EAST AND BE IN THE NEIGHBORHOOD BY WEDNESDAY. SW FLOW AHEAD OF IT WILL WARM TEMPS UP TO NR 40 AS AN AVERAGE BY THE MIDDLE OF THE WEEK. WILL MENTION RAIN OR SNOW TUESDAY AND WEDNESDAY WITH THE APPROACH OF THE SYSTEM. .MQT...WINTER STORM WARNING TONIGHT AND THURSDAY MORNING MIZ001>005-009 ...WINTER WEATHER ADVISORY LATE TONIGHT AND THURSDAY MIZ006-007-010-011-013-014 ...WINTER WEATHER ADVISORY THURSDAY MIZ012 ...GALE WARNING LAKE SUPERIOR ALTOE mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DULUTH MN 345 AM CST THU MAR 9 2000 MAIN FORECAST PROBLEM IS SNOWFALL IN NORTHWEST WISCONSIN AND BACK TOWARD DLH. MODELS FAIRLY SIMILAR ON HANDLING OF UPPER AND SFC FEATURES TODAY...WITH PERHAPS THE MAIN DIFFERENCE BEING THE AMOUNT OF CAA AT 850 MB WITH ETA AND RUC THE WARMEST. ALL DO AGREE THAT WE WILL HAVE DELTA T'S AT LEAST 13C DURING DAY...BUT ALSO KEEP INVERSION HEIGHTS BELOW 3000 FT. SO LAKE EFFECT TO KEEP SNOW ACCUMULATING FROM DLH-HURLEY...BUT WILL TAPER TO SCATTERED SNOW SHOWERS THIS AFTN AS DRY AIR CONTINUES TO WORK IN AND WITH SOME SUBSIDENCE. SOME HEAVY SNOW INLAND AT THE MOMENT AS WELL IN MAIN BAND SLOWLY ROTATING NORTHEAST ACROSS EASTERN CWA. SHOULD SEE THIS PERSIST EARLY THIS MORNING...BUT THEN DIMINISHING AS GOOD UVV MOVES OFF AS UPPER LOW OPENS AND MOVES EAST. HAD FREEZING DRIZZLE ALL OVER EARLIER ON SHIFT...AND WILL KEEP MENTION OF PATCHY STUFF EARLY. HIGH PRESSURE TNGT TO ALLOW FOR BELOW NORMAL TEMPS FOR ONCE... ALTHOUGH SOME HIGH CLOUDS ASSOCIATED WITH WEAK WAVE TO PREVENT THEM FROM GOING TO FAR. ALSO SOME HIGH CLOUDS AHEAD OF ANOTHER WAVE ON FRIDAY...BUT STILL PARTLY TO MOSTLY SUNNY. COORD WITH GRB...MQT AND MPX. THANKS! .DLH...WINTER WEATHER ADVISORY CONTINUES THIS MORNING FOR ALL OF NORTHWEST WISCONSIN AND MNZ037. mn SOUTH CENTRAL AND SOUTHEAST MONTANA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BILLINGS MT 128 AM MST THU MAR 09 2000 .TDY AND FRI... MAIN FLOW PATTERN ACROSS THE EASTERN PACIFIC SHIFTING NORTHWARD THE NEXT FEW DAYS AND ALLOWING CALIFORNIA AND SOUTHWEST TO DRY OUT A LITTLE. UPPER LEVEL NEGATIVELY TILTED ELONGATED TROUGH ALONG KMFR-KABQ AXIS THIS MORNING WILL BECOME SHEARED APART TODAY. NORTHWEST PORTION BEGINS TO FEEL WARM AIR ADVECTION FROM SYSTEM DEVELOPING ALONG 150W WHICH WILL BUILD RIDGING TOWARD THE PACIFIC NORTHWEST AND SLOWLY BUILD HEIGHTS OVER REGION TONIGHT AND FRIDAY. SOUTHERN PORTION OF TROUGH MOVES INTO EASTERN COLORADO BY THIS EVENING AND A WEAK CENTRAL PIECE TRACKS OVER CENTRAL WYOMING. SURFACE LOW ASSOCIATED WITH THIS WEAK SHORTWAVE CURRENTLY OVER SOUTHWEST IDAHO IS EXPECTED TO TRACK EAST INTO WYOMING TODAY AND SLIGHTLY INCREASE UPSLOPE FLOW ACROSS SOUTHERN MONTANA. SYSTEM IS NOT VERY DYNAMIC AND AT 700 MB LATEST RUC SHOWS THIS SYSTEM WILL BE TRANSITIONING FROM A WEAK CLOSED LOW TO AN OPEN WAVE TODAY. EXPECT CYCLONIC FLOW ALOFT WILL COMBINE WITH THE WEAK UPSLOPE FOR SCATTERED SNOW TODAY AND TONIGHT BEFORE WARMING ALOFT ON FRIDAY STABILIZES ATMOSPHERE. BEST CHANCE OF SNOW WILL BE OVER THE SOUTHWEST MOUNTAINS AND THE BIG HORN MOUNTAINS OF SHERIDAN COUNTY. WILL HAVE LIKELY POPS IN THE MOUNTAINS WITH LIGHT ACCUMULATIONS FIRST AND SECOND PERIODS. TEMPS A LITTLE TRICKY AND WILL MAKE NO CHANGES...BUT IF CLOUD COVER LINGERS ON FRIDAY MAXES MAY STRUGGLE TO REACH 40. BORSUM. .SAT...SUN...AND MON... WESTERLY FLOW ALOFT WILL SET-UP OVER MONTANA DURING THE DAY 3-5 PERIOD. AVN/MRF/NOGAPS/UKMET IN AGREEMENT WITH THE SHORTWAVES IN THE FLOW...WHEREAS ECMWF SLOWER. ONE SHORTWAVE WILL TRACK ACROSS SATURDAY AND ANOTHER WILL TRACK ACROSS MONDAY. DOWNSLOPING AND THE NORTHERN TRACK OF THE SHORTWAVES WILL PUT A DAMPER ON PRECIPITATION ACROSS THE FORECAST AREA AS THESE SYSTEMS MOVE THROUGH. I WILL DROP THE CHANCE OF SHOWERS TO SLIGHT CHANCE SATURDAY. MIDDENDORF BIL JEEEW /034 024/044 025/048 025/048 030/053 59330 61 LVM JEWEW /035 022/043 022/045 023/045 028/050 59442 61 HDN JEEEW /035 022/045 023/048 024/048 028/053 59330 61 MLS EEEEW /032 019/045 024/047 025/047 026/050 59220 61 4BQ JEEEW /031 017/043 023/044 023/044 025/050 59220 61 BHK EEEEW /029 015/040 021/042 024/044 024/048 59220 61 SHR JEEEW /036 020/040 021/047 022/047 024/050 59442 61 mt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTH PLATTE NE 233 PM CST WED MAR 8 2000 ...ALL KINDS OF WEATHER TODAY...WHEN WILL IT END.... 18Z SFC AND UPPER LOW STACKED IN NERN NEBR. TIGHT GRADIENT ON BACK SIDE HAS SLACKENED A LITTLE BUT NOT MUCH. 18Z RUC NOT AVAILABLE SO LOOKING AT THE 12Z ETA...QG FORCING SLIDES NORTH THRU 00Z THU WHICH IS THE TREND THAT IR PICS INDICATE. WATER VAPOR SHOWS WELL DEFINED MATURE CYCLONE WITH TYPICAL BENT BACK FRONT/T-BONE STRUCTURE. MODELS ARE SIMILAR WITH EXITING SYSTEM FOR THE MOST PART BUT DIFFER SOME ON TIMING/PLACEMENT OF INCOMING SYSTEM THU NIGHT. HAVE CHOSEN THE ETA BASED ON HISTORY OF THE LAST FEW SYSTEMS...BUT IT HAS SHIFTED ITS SOLUTION FURTHER NORTH SINCE 00Z WED RUN. FOR TONIGHT...LOW SHOULD CONTINUE TO LIFT NWD WITH DEFORMATION ZONE AND AXIS OF HEAVIEST PRECIP SHIFTING N INTO NRN SD. LAPSE RATES REMAIN HIGH OVER THE NERN PART OF THE CWA SO WILL CONTINUE MENTION OF SHRA FOR THE EVENING MIXING WITH OR CHANGING BRIEFLY TO SN. WILL GO WITH A WIND ADV FOR ALL ZONES BUT ERN PANHANDLE AND WILL WAIT TILL 3PM CST OBS TO DECIDE ON THEM. IN THE NC/NW...ECHOES DECREASING RAPIDLY ALREADY ON KLNX 88D AND WOULD EXPECT THIS TREND TO CONTINUE. WOULDNT BE SURPRISED TO GET AN INCH OR SO AS IT LIFTS OUT N OF A LINE FROM ARTHUR TO VTN...BUT SNOW HAS BEEN MELTING RATHER QUICKLY THIS AFTERNOON. FOR THE SW...A FEW SPIT THIS EVE BUT NOTHING AFTER THAT. DOWNSLOPE WINDS INTO THE NIGHT SHOULD INHIBIT FOG FORMATION. SUBSIDENCE OVERSPREADS THE AREA FOR THE FIRST HALF OF TOMORROW SO WE SHOULD SEE SOME SUNSHINE IN THE WEST...BUT CLOUDS HANG ON THE EAST THEN DECREASING IN THE PM. GRADIENT STILL SOMEWHAT TIGHT IN NERN ZONES TOMORROW MORNING...BUT SHOULD STAY IN THE BREEZY CAT. MUCH COLDER ALL THE WAY AROUND...BUT LIKE FAN TEMPS A LITTLE BETTER. WILL BRING IN THE PRECIP THURS NIGHT INTO FRIDAY SW. H8 TEMPS AND CRITICAL THICKNESSES INDICATE ALL SNOW. LESSER CHANCES FURTHER N. LIKE THE COOLER FWC NUMBERS FOR FRI...BUT THEY MAY BE A BIT TOO COOL AND WILL MODERATE THEM SOMEWHAT. IN THE EXTENDED...SOME DIFFERENCES BETWEEN EURO MODELS/CANADIAN MODELS/MRF. AFTER LATE WEEK STORM GOES BY...CWA RETURNS TO NW FLOW WHICH WILL BRING A WEAK SYSTEM THRU SAT. WILL INCLUDE -SN IN THE NRN ZONES FOR THE EXTENEDED...BUT LEAVE SRN ZONES DRY. SUNDAY MRF LOOKS TOO WARM BASED ON BACK DOOR FRONT THAT SWINGS THRU...BUT MONDAY LOOKS WARMER. .LBF...WIND ADVISORY TONIGHT ALL BUT ERN PANHANDLE JWS ne AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 340 AM CST THU MAR 9 2000 MUCH QUIETER TONIGHT...WITH ONLY SOME LINGERING LIGHT PRECIP AND STRONG WINDS TO DEAL WITH. LATEST SFC ANALYSIS SHOWS LOW PRESSURE CENTERED IN SOUTHWEST WISCONSIN...WITH TIGHT GRADIENT BACK INTO EASTERN CWA. 06Z MESOETA AND RUC FORECASTING LOW TO MOVE EAST INTO MICHIGAN FAIRLY QUICKLY THIS MORNING...ALLOWING GRADIENT TO RELAX A BIT. BOUNDARY LAYER WINDS FORECAST TO DIMINISH TO 20 TO 25 KTS BY 12Z...SO SEE NO NEED TO EXTEND WIND ADVISORY. WILL PUT MENTION OF A FEW HIGHER GUSTS EARLY THIS MORNING...BUT MOST AREAS SHOULD SEE WINDS DROP BELOW ADVISORY CRITERIA BEFORE SUNRISE. KFSD 88D PICKING UP AN AREA OF LIGHT SNOW ALONG AND EAST OF KBKX TO KYKN LINE...WITH SURFACE OBS STILL SHOWING SOME FLURRIES FARTHER TO THE WEST. WILL KEEP A MENTION OF THIS IN THROUGH THE MORNING... AFTER WHICH TIME UPPER FLOW BECOMES MORE ANTICYCLONIC AS WEAK RIDGE MOVES OVER THE AREA. TIME-HEIGHT LOOK AT TEMPERATURES STILL SHOWING WARM ENOUGH AIR ABOVE 900MB TO ALLOW SOME LIGHT FREEZING PRECIP TO MIX IN WITH THE LIGHT SNOW EARLY...ESPECIALLY IN MN/IA COUNTIES... BUT WITH CONTINUED COLD ADVECTION MOST AREAS SHOULD SWITCH TO ALL SNOW BY MID MORNING. HIGH PRESSURE RIDGE OVER WESTERN DAKOTAS THIS MORNING WILL MOVE INTO WESTERN CWA BY THIS EVENING...AND CONTINUE TO STRETCH BACK ACROSS EASTERN SECTIONS THROUGH FRIDAY. WEAK WAVE COMING DOWN TONIGHT MAY BE ENOUGH TO PRODUCE A FEW FLURRIES IN COLD AIR MASS ACROSS THE EAST...BUT OTHERWISE JUST LOOKING FOR MOSTLY CLOUDY SKIES. AS WINDS TURN BACK TO THE SOUTH AND WEST ACROSS WESTERN CWA ON FRIDAY...COULD SEE A LITTLE WARM ADVECTION SNOW DEVELOP LATER IN THE DAY...BUT WILL HOLD OFF ON INTRODUCING IT FOR NOW. DID NOT DEVIATE TOO MUCH FROM GUIDNACE TEMPS...BUT WENT A LITTLE HIGHER FOR LOWS TONIGHT. .FSD...NONE HAMEN sd AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA NATIONAL WEATHER SERVICE ABERDEEN SD 320 AM CST THU MAR 9 2000 MAIN FORECAST CHALLENGES TODAY WILL BE CLOUD COVER AND POSSIBILITY OF FLURRIES EARLY...WINDS THIS MORNING...AND TEMPS. MSAS ANALYSIS AT 08Z SHOWS SFC LOW OVER CNTL WI AND MOVG RAPIDLY EAST. ASSOCIATED SFC PRSR GRADIENT BEHIND THE LOW IS WEAKENING STEADILY...BUT STILL A DIFFERENCE OF 8 MB FM ABR TO EASTERN EDGE OF CWA. WINDS STILL IN 25G35KT RANGE THIS AREA...BUT SHOULD BE DECREASING AS LOW CONTINUES TO PULL AWAY. 88D SHOWING ONLY VERY LGT AND WDLY SCT RETURNS OVER EASTERN CWA. OBS STILL SHOWING SOME -SN BUT THIS SHOULD BE ONLY FLURRIES AND HAVE LEFT METNTION OF THIS IN EASTERN ZONES FOR THIS MORNING. RUC SHOWS STEADILY DECREASING LOW LEVEL RH ACROSS THIS AREA AND PULLS ALL REMAINING PRECIP TO EAST BY ABOUT 15Z. FOLLOWED AVN MOST CLOSELY FOR REMAINDER OF PD...IN GENERAL AGREEMENT WITH NCEP PREFERENCE AS EXPRESSED IN PMDHMD. BASED ON AVN TIME SECTS...EXPECT AT LEAST PARTIAL CLEARING MOST AREAS TODAY...ESPECIALLY WEST AS DRIER AIR ADVECTS IN FROM N. HIGH RH IN UPPER LEVELS REMAINS TONIGHT...SO HAVE INDICATED MOSTLY CLOUDY. FOR FRI...ETA DIVERGES FROM AVN AND NGM SOLUTIONS WITH DEVELOPMENT OF SOUTHERN STREAM UPPER LOW OVER E CO. NGM/AVN MORE ENERGETIC WITH THIS FEATURE WITH AVN A BIT FASTER AND FORMING A CUTOFF LOW AT 500 MB. ALL MODELS GENERALLY AGREE HOWEVER ON A WNW UPR FLOW OVER DAKOTAS...AND SHOW A WEAK CD FNT MOVING INTO ND AND NE MT BY SAT 00Z. AVN INDICATES AVE RH INCRG TO W/NW LATE FRI...AND EXPECT AN INCREASE IN CLOUDS TOWARD FRI EVE...BUT NONE OF THE MODELS GENERATE ANY PRECIP OVER OUR AREA BY THIS TIME. FOR TEMPS...HAVE TRENDED TOWARD COOLER FWC TEMPS WITH THE NEW SNOW COVER MOST AREAS...ESPECIALLY WEST AND CENTRAL. .ABR...NONE. LORENS sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 926 AM EST THU MAR 9 2000 I WILL CONTINUE CHANCE POP FOR NC MTNS AS A FEW SHOWERS AND TSTMS PERSIST IN EASTERN TN AND COULD SPREAD IN...BUT WILL NOT MENTION ELSEWHERE. RUC AND 6Z ETA SHOW SHORT WAVE ASSOCIATED WITH THIS PRECIPITATION PROGRESSING EAST INTO CWA LATE TODAY AND TONIGHT...BUT LACK OF LOW LEVEL MOISTURE AND INSTABILITY EAST OF MTNS SHOULD HOLD POPS BELOW 20 PERCENT. I WILL GO PARTLY SUNNY FOR ALL AREAS AS PLENTY OF AC AND CS SHOULD CONTINUE TO MOVE OVER US THROUGH THE AFTERNOON. TEMPS AND WINDS OK. .GSP...NONE. RBN sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 958 AM EST THU MAR 9 2000 PRE-FRONTAL CNVRGNC AHEAD OF COLD FRONT BACK OVER THE MIDWEST CONTG TO PUSH NARROW FAST MOVING BAND OF SHRA/TSRA OVER THE MTNS ATTM. GIVEN FAST MOVEMENT WOULD EXPECT SOME OF THIS ACTIVITY TO GO A BIT FARTHER EAST THAN EARLIER MODELS PROJECTED EVEN WITH LACK OF GOOD DEWPTS/INSTAB OVER THE WEST. THUS WILL BOOST POPS A BIT FOR SW VA/SE WVA FOR EARLY THIS AFTN BUT LKLY STAY IN CHCY RANGE GIVEN QUICK EXODUS AS S/W AND SPEED MAX PUSH NEWD. MODIFIED MORN RAOBS DO INDICATE SOME DECENT AFTN CAPE WEST OF THE BLUE RIDGE ALTHOUGH APRS CLDNS AND EARLY SHRA MAY PUT A LID ON ESPCLY GIVEN EXITING UVV AND DEEP WESTERLY FLOW WELL IN ADVANCE OF THE ACTUAL FRONT. ELSW...THINK COMBO OF DRY AIR SEEN OFF GSO RAOB AND MESO-ETA/RUC FCST OF DMNSHG DEEP RH EAST OF THE MTNS ENOUGH TO LIMIT CHCS ALTHOUGH WILL HAVE TO WATCH ERN SLOPES EARLY ON. DUE TO CLDNS/SHRA RECORD TEMPS MAY NOT BE REACHED ESPCLY FAR WEST WHERE WILL LKLY NEED TO LOWER TEMPS A LITTLE OTRW THICKNESS TEMPS MODIFIED FOR CLDNS LOOK OK. RECORD HIGHS FOR TDY: RNK 73/1964 VA...NONE. WV...NONE. NC...NONE. JH va SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PHOENIX AZ 940 AM MST THU MAR 9 2000 .SYNOPSIS... A WEATHER DISTURBANCE EXITING NORTHERN ARIZONA THIS MORNING...WILL BE FOLLOWED BY A RIDGE OF HIGH PRESSURE BUILDING INTO THE WESTERN STATES THE NEXT FEW DAYS. THIS WILL BRING DRY AND WARMER WEATHER TO THE SOUTHWEST INTO NEXT WEEK. .DISCUSSION... SERIES OF WEAK SYSTEMS ROTATING AROUND THE SWRN U.S. THIS MORNING AS EASTERN PACIFIC RIDGE BUILDS. MAIN SYSTEM WAS NEAR 4 CRNRS WHILE A MUCH WEAKER ONE WAS SEEN NR YUMA. 12Z RUC HAD A GOOD HANDLE ON THIS VORT MAX THAT DRIFTED INTO YUMA CO EARLY THIS MORNING...AND RESULTANT HIGH LVL MSTR SPREAD ACROSS CNTRL AND EASTERN AZ. BY 15Z CLOUDS WERE THINNING AND LIFTING NE AS 500MB JET CORE SHIFTS FROM SOUTH OF PHX TO JUST NORTH OF PHX. 300MB WINDS LIKELY TO INCREASE ONCE AGAIN ON BACK SIDE OF NEW UPPER TROF BY TOMORROW MORNING. SOUNDINGS ALSO FAIRLY DRY AND ALONG WITH GOES PRECIP WATER VALUES OF .25 TO .45 IN OUR AREA THIS MORNING...WILL EXPECT P/CLDY CONDITIONS TO CONTINUE. THIS SLOW LOSS OF PRECIP WATER WAS TRENDED NICELY WED BY AVN AND WILL LIKELY SEE THIS TREND ACCELERATE A LITTLE MORE AS RIDGE SHIFTS EAST. EXPECT SLOW RECOVERY TOWARD AVERAGE MAX TEMPS FOR PHX THE NEXT FEW DAYS...AS LIGHT WINDS/LTL MIXING CONTINUE. NO CHANGES OR UPDATES. SIPPLE N az