Forecast Discussions mentioning "ACARS", "MDCRS", "AIRCRAFT", "TAMDAR", or "AMDAR" received at FSL on 03/08/08

AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
834 PM EST FRI MAR 7 2008 .MESOSCALE UPDATE #2... OVER THE LAST HOUR RADAR TRENDS HAVE SHOWN THAT MOISTURE HAS RETURNED TO THE REGION BOTH AT THE SFC AND ALOFT. SUFFICIENT MOISTURE HAS RETURNED IN THE -10 TO -12 DEG C LAYER TO CHANGE PRECIPITATION TO SNOW AT MOST REPORTING LOCATIONS INCLUDING LEXINGTON...BOWLING GREEN AND LOUISVILLE. MOISTURE HAS RETURNED SO QUICKLY THAT REPORTS HAVE STATED THAT THE SNOW FLAKES ARE QUITE LARGE...SOME AS BIG AS QUARTERS DOWN IN THE RADCLIFF AREA. THIS MAKES SENSE GIVEN THE HIGHER REFLECTIVITIES DOWN IN THAT REGION. CURRENT DEFORMATION ZONE APPEARS TO BE SETTING UP FROM BUTLER COUNTY NE THROUGH BRECKINRIDGE...HARDIN...MEADE AND INTO HARRISON...FLOYD AND CLARK COUNTIES IN INDIANA. SNOWFALL RATES OF 1-2 INCHES PER HOUR WILL BE POSSIBLE. TRAFFIC CAMERAS FROM AROUND METRO LOUISVILLE INDICATE THAT MOST OF THE MAJOR INTERSTATES (65-64 AND I-264) ARE IN FACT SNOW COVERED. THUS...TRAVELING WILL BECOME DIFFICULT. FURTHER EAST IN THE BEAUTIFUL BLUEGRASS REGION...SNOW IS PICKING UP AND WILL GRADUALLY INCREASE IN INTENSITY LATER TONIGHT AS LARGE SCALE ASCENT MOVES INTO THE REGION. WITH TEMPS IN THE MID AND UPPER 20S...ROAD CONDITIONS ON THE I-64...I-71 AND I-75 WILL BECOME INCREASINGLY DIFFICULT. SO IN SUMMARY...WE ANTICIPATE THE HEAVIEST SNOWFALL ACTIVITY TO BE CONFINED TO AREAS ALONG AND WEST OF I-65 FOR THE NEXT FEW HOURS. LATEST HIGH REZ IN-HOUSE WRF MODEL SUGGESTS THAT HEAVIER PRECIP WILL MOVE INTO EASTERN SECTIONS LATER TONIGHT...AND DEFORMATION ZONE SHOULD ALSO PUSH EASTWARD VERY SLOWLY WITH TIME. MESOSCALE UPDATE #1... KLVX RADAR DATA SHOWING THAT RETURNS ARE RAPIDLY INCREASING IN THE I-65 CORRIDOR...MAINLY FROM NEAR KBWG NE THROUGH E-TOWN AND UP TO KSDF. WBKO IN BOWLING GREEN HAS BEEN REPORTING QUITE A BIT OF FREEZING DRIZZLE/RAIN OVER THE PAST HOUR THAT HAS PRODUCED A GLAZE ON EXPOSED OBJECTS. ONE NWS STAFF MEMBER HERE IN THE CITY REPORTED A MIX OF FZRA AND SLEET. AREA ACARS SOUNDINGS OUT OF KSDF SHOW A THERMAL PROFILE COMPLETELY BELOW ZERO DEG C. SO IT APPEARS THAT THE DRY AIR PUNCH HAS ERODED THE MOISTURE IN THE CRITICAL -10 TO -12 DEG C ICE CRYSTAL LAYER WHICH WOULD PROMOTE MORE OF A SLEET/FREEZING RAIN SITUATION. WITH LARGE SCALE ASCENT MOVING BACK INTO THE REGION ALONG WITH INCREASING MOISTURE...THIS IP/FZRA HERE IN THE LOUISVILLE AREA SHOULD QUICKLY CHANGE BACK TO SNOW WITHIN THE HOUR AS ICE CRYSTAL PRODUCTION QUICKLY RAMPS BACK UP. FURTHER SOUTH IN THE KBWG AREA...SOME LIGHT FZRA WILL CONTINUE FOR A TIME AS SOME WARM AIR ALOFT REMAINS. THIS SHOULD COOL WITHIN THE NEXT FEW HOURS DUE TO EVAP COOLING ASSOCIATED WITH LARGE SCALE ASCENT. FURTHER EAST IN THE LEXINGTON AREA...DRY SLOT WILL ALSO PRODUCE THE SAME EFFECT AS HERE IN LOUISVILLE WITH SOME FZRA/FZDZ OR SLEET FOR A TIME THIS EVENING. AS MOISTURE RETURNS A QUICK CHANGE BACK TO SNOW WILL OCCUR. THE 18Z MODELS ARE STILL IN GOOD AGREEMENT WITH OUR PREVIOUS FCSTS AND NO FCST CHANGES ARE REQUIRED AT THE MOMENT. .SHORT TERM (TONIGHT AND SATURDAY)... ...WINTER STORM TO CONTINUE TONIGHT AND SATURDAY MORNING AND EXPAND SOUTH AND EAST OVERNIGHT AND SATURDAY... IMPRESSIVE FRONTOGENETICAL BAND OF HEAVY SNOW AT 3 PM EST EXTENDED FROM NEAR E-TOWN THROUGH SPENCER AND SHELBY COUNTIES TO AROUND FFT. SNOWFALL RATES OF ABOUT 2 INCHES PER HOUR WERE OCCURRING IN THIS BAND. AS OF 3 PM...NWS LOUISVILLE HAD NEARLY 4.5 INCHES (WAS AFFECTED BY THIS BAND) WHILE SDF AIRPORT HAD 2-2.5 INCHES. SNOW WILL CONTINUE OVER N-CENTRAL KY AND S-CENTRAL IN THROUGH LATE AFTERNOON WITH HEAVIEST SNOW JUST SOUTH AND EAST OF LOUISVILLE (ALTHOUGH BAND MAY WEAKEN)...AS EXIT REGION OF UPR-LEVEL JET STREAK HEADS ACROSS TN VALLEY AND KY. WATER VAPOR IMAGERY SHOWS UPR-LEVEL DRY SLOT/CORE OF JET STREAK WORKING NEWD ACROSS MS AND WRN TN. RADARS IN THE AREA SHOW LESS PRECIP COVERAGE IN THIS AREA. MODELS FCST JET STREAK TO WORK INTO KY TONIGHT FOR AWHILE...WHICH MAY RESULT IN SOME DIMINISHING OF PRECIP IN CENTRAL KY WITH PRECIP PIVOTING NWWD TO LEFT OF JET CORE. NEVERTHELESS...MODEL TIME HEIGHT CROSS-SECTIONS SHOW PLENTY OF LOW AND MID LEVEL MOISTURE AND SOME VERTICAL MOTION TO CONTINUE TO PRODUCE SOME PRECIP. MAIN SHORTWAVE OVER NRN LA AT THIS TIME WILL WORK NEWD TONIGHT AND SAT. CURRENTLY...MDT TO HEAVY SNOW IS OCCURRING JUST AHEAD OF THIS SYSTEM OVER ARK WITHIN DEFORMATION AXIS JUST W OF UPR JET CORE. IN FACT...A FEW CG LIGHTNING STRIKES HAVE BEEN OBSERVED IN THIS AREA DUE TO STEEP 700-500 MB LAPSE RATES COUPLED WITH STRONG VERTICAL MOTION. DEFORMATION ZONE WILL MOVE NEWD INTO KY LATER TONIGHT AND SAT MORNING BRINGING MDT TO HEAVY SNOW WITH IT. MAIN FCST PROBLEM IS DETERMINING EXACTLY HOW THIS AREA OF DEFORMATION SNOW WILL EVOLVE AS IT UPR LOW ROTATES NEWD. MODELS SUGGEST THIS AXIS WILL TRANSLATE NEWD TO A LINE ROUGHLY FROM BWG TO SDF AND POINTS N AND W. STEEP MID LVL LAPSE RATES ALSO TO TRANSLATE NEWD SO BANDED SNOWFALL IS LIKELY AND A CLAP OR TWO OF THUNDER CANNOT BE RULED OUT TONIGHT INTO EARLY SAT. GFS...OPERATIONAL NAM...AND IN-HOUSE HI-RESOLUTION NAM-WRF ALSO SUGGEST THAT THIS ORIGINAL DEFORMATION ZONE MAY REFORM WITH TIME A BIT FARTHER EWD OVER CENTRAL KY INCLUDING THE BLUEGRASS AREA LATE TONIGHT AND SAT WHILE ORIGINAL AREA WEAKENS A BIT. UKMET AND ECMWF MAINTAIN PRIMARY BAND LONGER. IF IT REFORMS...THIS IS ONE OF THE REASONS FOR MAINTAINING HIGHER SNOW AMOUNTS OVER BLUEGRASS...BEFORE WRAP AROUND SNOWS TRANSLATE ACROSS ENTIRE AREA ON SAT BRINGING SOME ADDITIONAL SNOWFALL. APPEARS ELEVATED ABOVE FREEZING AIR WILL REMAIN ACROSS OUR SERN COUNTIES (INCLUDING BURKESVILLE AND ALBANY) WELL INTO TONIGHT...BUT LOW-LEVEL COLD AIR WILL STRENGTHEN WITH TIME LEADING TO FREEZING RAIN AND SLEET TONIGHT WHICH COULD CAUSE SIGNIFICANT PROBLEMS. THEN EXPECT A PERIOD OF ACCUMULATING SNOW ON SAT AS UPR LOW PASSES BY. FOR THESE REASONS...OUR FAR SERN AREAS WILL BE UPGRADED TO A WINTER STORM WARNING THROUGH SAT AFTERNOON. PROJECTED STORM TOTAL SNOWFALL (WHICH INCLUDES SNOW THAT HAS ALREADY FALLEN TODAY) IS AS FOLLOWS: 10-14 INCHES: N-CENTRAL KY FROM TRIMBLE/HENRY TO HARDIN COUNTIES 05-10 INCHES: ALL OF S-CENTRAL IN AND PARTS OF W-CENTRAL KY 06-10 INCHES: NRN BLUEGRASS AREA INCLUDING LEX AND FFT 03-06 INCHES: S-CENTRAL KY INCLUDING BWG TO CAMPBELLSVILLE TO RICHMOND 01-03 INCHES: RUSSELL CUMBERLAND CLINTON AND MONROE COUNTIES THE TOTALS OVER ERN PART OF FCST AREA...INCLUDING MUCH OF THE BLUEGRASS AND LEX AREAS (LITTLE SNOW HAS OCCURRED SO FAR IN LEX)... DEPENDS HIGHLY ON EVOLUTION OF DEFORMATION SNOWFALL AND UPR LOW PATH TONIGHT AND SAT. IF BANDING DEVELOPS IN THESE AREAS OVERNIGHT AND SAT...THEN THESE TOTALS SHOULD BE REALIZED. IF NOT...THEN ACTUAL AMOUNTS LIKELY WILL BE A LITTLE LOWER. CURRENTLY...SNOWFALL IS RATHER WET I.E. HIGH SNOW TO LIQUID RATIOS. THUS SHOVELING SNOW WILL CAUSE GREATER STRESS FOR INDIVIDUALS. EXTREME CAUTION IS RECOMMENDED. LATE TONIGHT AND SAT...THE SNOW SHOULD BECOME DRIER I.E. LOWER SNOW RATIOS. THUS...BLOWING AND DRIFTING SNOW WILL BECOME AN INCREASING PROBLEM OVERNIGHT AND SAT. .LONG TERM (SATURDAY NIGHT THROUGH THURSDAY)... UPPER AIR PATTERN EARLY IN THE EXTENDED WILL FEATURE AN AMPLIFIED PATTERN WITH TROUGHING ACROSS THE GREAT LAKES AND A FULL LATITUDE RIDGE ALONG THE WEST COAST. THE GREAT LAKES TROUGH WILL KEEP THE LOWER OHIO VALLEY COOL THROUGH MONDAY. A FLATTENING OF THE UPPER AIR PATTERN BY MID-WEEK WILL ALLOW A MODERATING TREND AND SOMEWHAT WARMER TEMPERATURES BY MID WEEK. GOOD NEWS FOR THE EXTENDED WILL BE A LACK OF SIGNIFICANT PRECIPITATION...UNTIL PERHAPS LATE THURSDAY. ONE LAST DISTURBANCE WILL SLIDE SOUTH DOWN THE WEST SIDE OF THE GREAT LAKES TROUGH LATE SUNDAY AND EARLY MONDAY. THIS CLIPPER SYSTEM MAY BRING A VERY LIGHT MIX OF RAIN OR SNOW EARLY MONDAY AS LOW PRESSURE MOVES ACROSS OHIO. THE WEAK COLD AIR PUSH BEHIND THIS SYSTEM WILL KEEP MONDAY COOL...ALTHOUGH SKIES WILL BECOME PARTLY CLOUDY MONDAY AFTERNOON. SOUTHWESTERLY FLOW WILL COMMENCE TUESDAY AS THE GREAT LAKES TROUGH LOSES ITS INFLUENCE. TEMPERATURES WILL MODERATE INTO THE MID TO UPPER 50S...WHICH IS SEASONAL FOR EARLY MARCH. DEEP LOW PRESSURE WILL MOVE NORTH OF THE GREAT LAKES EARLY THURSDAY AND TRAIL A COLD FRONT ACROSS THE UPPER MIDWEST THAT WILL APPROACH THE LOWER OHIO VALLEY. MODIFIED MOISTURE WILL RETURN FROM THE GULF AHEAD OF THIS FRONT...AS SOUTH WINDS INCREASE. HAVE INSERTED A CHANCE OF SHOWERS LATE THURSDAY AND EARLY FRIDAY. && .AVIATION (00Z TAFS)... ...MAJOR WINTER WEATHER WILL IMPACT AREA TERMINALS TONIGHT... DEEPENING STORM SYSTEM OVER THE GULF COAST STATES WILL MOVE NORTHEAST TOWARD THE REGION TONIGHT. PRECIPITATION HAS ENDED TEMPORARILY AT KLEX. SOME LIGHT SNOW AND LIGHT FREEZING RAIN CONTINUES AT KSDF AND KBWG AND PRECIPITATION SHOULD BEGIN TO PICK BACK UP ONCE AGAIN LATER TONIGHT. TO HELP IN PLANNING...WILL BREAK DOWN THE FCST FOR EACH TERMINAL... FOR KBWG...THERMAL PROFILES AND OBSERVATIONS CONTINUE TO SHOW A SHALLOW WARM LAYER ALOFT WHICH CONTINUES TO PRODUCE SOME LIGHT FREEZING RAIN. AS STORM SYSTEM LIFTS NORTH...SUFFICIENT COOLING IS EXPECTED TO TRANSITION PRECIPITATION FROM FZRA TO SNOW AROUND 02-03Z. MOD-HVY SNOW BAND SHOULD IMPACT THE TERMINAL OVERNIGHT...PROBABLY IN THE 04-08Z TIME FRAME. IN GENERAL...MAINLY IFR CONDITIONS ARE EXPECTED WITH POSSIBLE DIPS INTO THE LIFR AND EVEN POSSIBLY A BRIEF DIP TO VLIFR FOR A TIME OVERNIGHT. CONDITIONS SHOULD IMPROVE SAT MORNING. FOR KSDF...LIGHT SNOW CONTINUES RIGHT NOW AND SHOULD GRADUALLY LET UP SHORTLY WITH A BRIEF LULL IN THE PRECIP UNTIL MID EVENING. RADAR SHOWS INCREASING RETURNS TO OUR WEST THAT ARE HEADING EAST. SO CONDITIONS SHOULD BEGIN TO GO DOWNHILL AT KSDF BY MID-EVENING. LATEST MODELS SUGGEST HEAVY SNOW BAND TRANSITIONING ACROSS THE TERMINAL OVERNIGHT WITH THE WORST CONDITIONS EXPECTED TO BE IN THE 05-09Z TIME FRAME. BELIEVE THAT CONDITIONS WILL BE SIMILAR TO WHAT WE SAW EARLIER TODAY WITH LIFR AND POSSIBLY VLIFR CONDITIONS AT TIMES AS THE BAND MOVES THROUGH. FOR KLEX...PRECIPITATION HAS ALSO ENDED HERE FOR THE TIME BEING. HOWEVER SOME VERY FINE LIGHT SNOW WILL PERSIST THROUGH THE EVENING. AS WITH KSDF...MODELS CONTINUE TO DEVELOP A HEAVY SNOW BAND WHICH WILL MOVE INTO THE TERMINAL LATE TONIGHT. VSBYS AND CIGS WILL DROP INTO THE IFR AND LIFR CATEGORY AND MAY BRIEFLY FLIRT WITH VLIFR CATS AT TIMES...ESPECIALLY IN THE 06-10Z TIME FRAME. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...WINTER STORM WARNING FOR ALL OF CENTRAL KENTUCKY UNTIL 4 PM EST /3 PM CST/ SATURDAY. IN...WINTER STORM WARNING FOR SOUTH CENTRAL INDIANA UNTIL 4 PM EST /3 PM CST/ SATURDAY. && $$ UPDATE.......MJ SHORT TERM...TWF/JDK LONG TERM....JSD AVIATION.....MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
716 PM EST FRI MAR 7 2008 .MESOSCALE UPDATE... KLVX RADAR DATA SHOWING THAT RETURNS ARE RAPIDLY INCREASING IN THE I-65 CORRIDOR...MAINLY FROM NEAR KBWG NE THROUGH E-TOWN AND UP TO KSDF. WBKO IN BOWLING GREEN HAS BEEN REPORTING QUITE A BIT OF FREEZING DRIZZLE/RAIN OVER THE PAST HOUR THAT HAS PRODUCED A GLAZE ON EXPOSED OBJECTS. ONE NWS STAFF MEMBER HERE IN THE CITY REPORTED A MIX OF FZRA AND SLEET. AREA ACARS SOUNDINGS OUT OF KSDF SHOW A THERMAL PROFILE COMPLETELY BELOW ZERO DEG C. SO IT APPEARS THAT THE DRY AIR PUNCH HAS ERODED THE MOISTURE IN THE CRITICAL -10 TO -12 DEG C ICE CRYSTAL LAYER WHICH WOULD PROMOTE MORE OF A SLEET/FREEZING RAIN SITUATION. WITH LARGE SCALE ASCENT MOVING BACK INTO THE REGION ALONG WITH INCREASING MOISTURE...THIS IP/FZRA HERE IN THE LOUISVILLE AREA SHOULD QUICKLY CHANGE BACK TO SNOW WITHIN THE HOUR AS ICE CRYSTAL PRODUCTION QUICKLY RAMPS BACK UP. FURTHER SOUTH IN THE KBWG AREA...SOME LIGHT FZRA WILL CONTINUE FOR A TIME AS SOME WARM AIR ALOFT REMAINS. THIS SHOULD COOL WITHIN THE NEXT FEW HOURS DUE TO EVAP COOLING ASSOCIATED WITH LARGE SCALE ASCENT. FURTHER EAST IN THE LEXINGTON AREA...DRY SLOT WILL ALSO PRODUCE THE SAME EFFECT AS HERE IN LOUISVILLE WITH SOME FZRA/FZDZ OR SLEET FOR A TIME THIS EVENING. AS MOISTURE RETURNS A QUICK CHANGE BACK TO SNOW WILL OCCUR. THE 18Z MODELS ARE STILL IN GOOD AGREEMENT WITH OUR PREVIOUS FCSTS AND NO FCST CHANGES ARE REQUIRED AT THE MOMENT. .SHORT TERM (TONIGHT AND SATURDAY)... ...WINTER STORM TO CONTINUE TONIGHT AND SATURDAY MORNING AND EXPAND SOUTH AND EAST OVERNIGHT AND SATURDAY... IMPRESSIVE FRONTOGENETICAL BAND OF HEAVY SNOW AT 3 PM EST EXTENDED FROM NEAR E-TOWN THROUGH SPENCER AND SHELBY COUNTIES TO AROUND FFT. SNOWFALL RATES OF ABOUT 2 INCHES PER HOUR WERE OCCURRING IN THIS BAND. AS OF 3 PM...NWS LOUISVILLE HAD NEARLY 4.5 INCHES (WAS AFFECTED BY THIS BAND) WHILE SDF AIRPORT HAD 2-2.5 INCHES. SNOW WILL CONTINUE OVER N-CENTRAL KY AND S-CENTRAL IN THROUGH LATE AFTERNOON WITH HEAVIEST SNOW JUST SOUTH AND EAST OF LOUISVILLE (ALTHOUGH BAND MAY WEAKEN)...AS EXIT REGION OF UPR-LEVEL JET STREAK HEADS ACROSS TN VALLEY AND KY. WATER VAPOR IMAGERY SHOWS UPR-LEVEL DRY SLOT/CORE OF JET STREAK WORKING NEWD ACROSS MS AND WRN TN. RADARS IN THE AREA SHOW LESS PRECIP COVERAGE IN THIS AREA. MODELS FCST JET STREAK TO WORK INTO KY TONIGHT FOR AWHILE...WHICH MAY RESULT IN SOME DIMINISHING OF PRECIP IN CENTRAL KY WITH PRECIP PIVOTING NWWD TO LEFT OF JET CORE. NEVERTHELESS...MODEL TIME HEIGHT CROSS-SECTIONS SHOW PLENTY OF LOW AND MID LEVEL MOISTURE AND SOME VERTICAL MOTION TO CONTINUE TO PRODUCE SOME PRECIP. MAIN SHORTWAVE OVER NRN LA AT THIS TIME WILL WORK NEWD TONIGHT AND SAT. CURRENTLY...MDT TO HEAVY SNOW IS OCCURRING JUST AHEAD OF THIS SYSTEM OVER ARK WITHIN DEFORMATION AXIS JUST W OF UPR JET CORE. IN FACT...A FEW CG LIGHTNING STRIKES HAVE BEEN OBSERVED IN THIS AREA DUE TO STEEP 700-500 MB LAPSE RATES COUPLED WITH STRONG VERTICAL MOTION. DEFORMATION ZONE WILL MOVE NEWD INTO KY LATER TONIGHT AND SAT MORNING BRINGING MDT TO HEAVY SNOW WITH IT. MAIN FCST PROBLEM IS DETERMINING EXACTLY HOW THIS AREA OF DEFORMATION SNOW WILL EVOLVE AS IT UPR LOW ROTATES NEWD. MODELS SUGGEST THIS AXIS WILL TRANSLATE NEWD TO A LINE ROUGHLY FROM BWG TO SDF AND POINTS N AND W. STEEP MID LVL LAPSE RATES ALSO TO TRANSLATE NEWD SO BANDED SNOWFALL IS LIKELY AND A CLAP OR TWO OF THUNDER CANNOT BE RULED OUT TONIGHT INTO EARLY SAT. GFS...OPERATIONAL NAM...AND IN-HOUSE HI-RESOLUTION NAM-WRF ALSO SUGGEST THAT THIS ORIGINAL DEFORMATION ZONE MAY REFORM WITH TIME A BIT FARTHER EWD OVER CENTRAL KY INCLUDING THE BLUEGRASS AREA LATE TONIGHT AND SAT WHILE ORIGINAL AREA WEAKENS A BIT. UKMET AND ECMWF MAINTAIN PRIMARY BAND LONGER. IF IT REFORMS...THIS IS ONE OF THE REASONS FOR MAINTAINING HIGHER SNOW AMOUNTS OVER BLUEGRASS...BEFORE WRAP AROUND SNOWS TRANSLATE ACROSS ENTIRE AREA ON SAT BRINGING SOME ADDITIONAL SNOWFALL. APPEARS ELEVATED ABOVE FREEZING AIR WILL REMAIN ACROSS OUR SERN COUNTIES (INCLUDING BURKESVILLE AND ALBANY) WELL INTO TONIGHT...BUT LOW-LEVEL COLD AIR WILL STRENGTHEN WITH TIME LEADING TO FREEZING RAIN AND SLEET TONIGHT WHICH COULD CAUSE SIGNIFICANT PROBLEMS. THEN EXPECT A PERIOD OF ACCUMULATING SNOW ON SAT AS UPR LOW PASSES BY. FOR THESE REASONS...OUR FAR SERN AREAS WILL BE UPGRADED TO A WINTER STORM WARNING THROUGH SAT AFTERNOON. PROJECTED STORM TOTAL SNOWFALL (WHICH INCLUDES SNOW THAT HAS ALREADY FALLEN TODAY) IS AS FOLLOWS: 10-14 INCHES: N-CENTRAL KY FROM TRIMBLE/HENRY TO HARDIN COUNTIES 05-10 INCHES: ALL OF S-CENTRAL IN AND PARTS OF W-CENTRAL KY 06-10 INCHES: NRN BLUEGRASS AREA INCLUDING LEX AND FFT 03-06 INCHES: S-CENTRAL KY INCLUDING BWG TO CAMPBELLSVILLE TO RICHMOND 01-03 INCHES: RUSSELL CUMBERLAND CLINTON AND MONROE COUNTIES THE TOTALS OVER ERN PART OF FCST AREA...INCLUDING MUCH OF THE BLUEGRASS AND LEX AREAS (LITTLE SNOW HAS OCCURRED SO FAR IN LEX)... DEPENDS HIGHLY ON EVOLUTION OF DEFORMATION SNOWFALL AND UPR LOW PATH TONIGHT AND SAT. IF BANDING DEVELOPS IN THESE AREAS OVERNIGHT AND SAT...THEN THESE TOTALS SHOULD BE REALIZED. IF NOT...THEN ACTUAL AMOUNTS LIKELY WILL BE A LITTLE LOWER. CURRENTLY...SNOWFALL IS RATHER WET I.E. HIGH SNOW TO LIQUID RATIOS. THUS SHOVELING SNOW WILL CAUSE GREATER STRESS FOR INDIVIDUALS. EXTREME CAUTION IS RECOMMENDED. LATE TONIGHT AND SAT...THE SNOW SHOULD BECOME DRIER I.E. LOWER SNOW RATIOS. THUS...BLOWING AND DRIFTING SNOW WILL BECOME AN INCREASING PROBLEM OVERNIGHT AND SAT. .LONG TERM (SATURDAY NIGHT THROUGH THURSDAY)... UPPER AIR PATTERN EARLY IN THE EXTENDED WILL FEATURE AN AMPLIFIED PATTERN WITH TROUGHING ACROSS THE GREAT LAKES AND A FULL LATITUDE RIDGE ALONG THE WEST COAST. THE GREAT LAKES TROUGH WILL KEEP THE LOWER OHIO VALLEY COOL THROUGH MONDAY. A FLATTENING OF THE UPPER AIR PATTERN BY MID-WEEK WILL ALLOW A MODERATING TREND AND SOMEWHAT WARMER TEMPERATURES BY MID WEEK. GOOD NEWS FOR THE EXTENDED WILL BE A LACK OF SIGNIFICANT PRECIPITATION...UNTIL PERHAPS LATE THURSDAY. ONE LAST DISTURBANCE WILL SLIDE SOUTH DOWN THE WEST SIDE OF THE GREAT LAKES TROUGH LATE SUNDAY AND EARLY MONDAY. THIS CLIPPER SYSTEM MAY BRING A VERY LIGHT MIX OF RAIN OR SNOW EARLY MONDAY AS LOW PRESSURE MOVES ACROSS OHIO. THE WEAK COLD AIR PUSH BEHIND THIS SYSTEM WILL KEEP MONDAY COOL...ALTHOUGH SKIES WILL BECOME PARTLY CLOUDY MONDAY AFTERNOON. SOUTHWESTERLY FLOW WILL COMMENCE TUESDAY AS THE GREAT LAKES TROUGH LOSES ITS INFLUENCE. TEMPERATURES WILL MODERATE INTO THE MID TO UPPER 50S...WHICH IS SEASONAL FOR EARLY MARCH. DEEP LOW PRESSURE WILL MOVE NORTH OF THE GREAT LAKES EARLY THURSDAY AND TRAIL A COLD FRONT ACROSS THE UPPER MIDWEST THAT WILL APPROACH THE LOWER OHIO VALLEY. MODIFIED MOISTURE WILL RETURN FROM THE GULF AHEAD OF THIS FRONT...AS SOUTH WINDS INCREASE. HAVE INSERTED A CHANCE OF SHOWERS LATE THURSDAY AND EARLY FRIDAY. && .AVIATION (00Z TAFS)... ...MAJOR WINTER WEATHER WILL IMPACT AREA TERMINALS TONIGHT... DEEPENING STORM SYSTEM OVER THE GULF COAST STATES WILL MOVE NORTHEAST TOWARD THE REGION TONIGHT. PRECIPITATION HAS ENDED TEMPORARILY AT KLEX. SOME LIGHT SNOW AND LIGHT FREEZING RAIN CONTINUES AT KSDF AND KBWG AND PRECIPITATION SHOULD BEGIN TO PICK BACK UP ONCE AGAIN LATER TONIGHT. TO HELP IN PLANNING...WILL BREAK DOWN THE FCST FOR EACH TERMINAL... FOR KBWG...THERMAL PROFILES AND OBSERVATIONS CONTINUE TO SHOW A SHALLOW WARM LAYER ALOFT WHICH CONTINUES TO PRODUCE SOME LIGHT FREEZING RAIN. AS STORM SYSTEM LIFTS NORTH...SUFFICIENT COOLING IS EXPECTED TO TRANSITION PRECIPITATION FROM FZRA TO SNOW AROUND 02-03Z. MOD-HVY SNOW BAND SHOULD IMPACT THE TERMINAL OVERNIGHT...PROBABLY IN THE 04-08Z TIME FRAME. IN GENERAL...MAINLY IFR CONDITIONS ARE EXPECTED WITH POSSIBLE DIPS INTO THE LIFR AND EVEN POSSIBLY A BRIEF DIP TO VLIFR FOR A TIME OVERNIGHT. CONDITIONS SHOULD IMPROVE SAT MORNING. FOR KSDF...LIGHT SNOW CONTINUES RIGHT NOW AND SHOULD GRADUALLY LET UP SHORTLY WITH A BRIEF LULL IN THE PRECIP UNTIL MID EVENING. RADAR SHOWS INCREASING RETURNS TO OUR WEST THAT ARE HEADING EAST. SO CONDITIONS SHOULD BEGIN TO GO DOWNHILL AT KSDF BY MID-EVENING. LATEST MODELS SUGGEST HEAVY SNOW BAND TRANSITIONING ACROSS THE TERMINAL OVERNIGHT WITH THE WORST CONDITIONS EXPECTED TO BE IN THE 05-09Z TIME FRAME. BELIEVE THAT CONDITIONS WILL BE SIMILAR TO WHAT WE SAW EARLIER TODAY WITH LIFR AND POSSIBLY VLIFR CONDITIONS AT TIMES AS THE BAND MOVES THROUGH. FOR KLEX...PRECIPITATION HAS ALSO ENDED HERE FOR THE TIME BEING. HOWEVER SOME VERY FINE LIGHT SNOW WILL PERSIST THROUGH THE EVENING. AS WITH KSDF...MODELS CONTINUE TO DEVELOP A HEAVY SNOW BAND WHICH WILL MOVE INTO THE TERMINAL LATE TONIGHT. VSBYS AND CIGS WILL DROP INTO THE IFR AND LIFR CATEGORY AND MAY BRIEFLY FLIRT WITH VLIFR CATS AT TIMES...ESPECIALLY IN THE 06-10Z TIME FRAME. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...WINTER STORM WARNING FOR ALL OF CENTRAL KENTUCKY UNTIL 4 PM EST /3 PM CST/ SATURDAY. IN...WINTER STORM WARNING FOR SOUTH CENTRAL INDIANA UNTIL 4 PM EST /3 PM CST/ SATURDAY. && $$ UPDATE.......MJ SHORT TERM...TWF/JDK LONG TERM....JSD AVIATION.....MJ
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
937 PM CST FRI MAR 7 2008 .DISCUSSION... LIGHT SNOW OVER NE OK DRIFTING SOUTHEAST WITH WEAK DISTURBANCE. BUT EVENT ESSENTIALLY OVER. MAY SEE ISOLATED LIGHT RAIN OR LIGHT SNOW...BUT NO ACCUMULATIONS EXPECTED. ISSUED PUBLIC INFO STATEMENT REVIEWING THE EVENT. WINTER WEATHER ADVISORY EXPIRED AT 9 PM. NO UPDATE TO TEMP FORECAST TONIGHT BUT DID LOWER LATE EVENING POPS FOR ELD/MLU FROM 40 PCT TO 20 PCT. /17/ && .AVIATION... NORTHWEST WINDS PICKING UP A BIT ALONG THE RED RIVER OF SE OK/NE TX. COLD AIR ADVECTION IS DRYING OUT THE LOWER LEVELS...BUT SEVERAL SMALL CLUSTERS OF SHOWERS COULD LEAD TO MINOR AIRCRAFT ICING ON DEPARTURE OR ASCENT W/ FZL LEVEL FROM KSHV SOUNDING AT FL022. MOST SFC OBS ARE IN THE MID TO UPPER 30S AT THIS HOUR. DRY LOBE PER WATER VAPOR LIES OVER NE TX FROM KFWD TO KSLR W/ SHOWERS DEVELOPING ON THE EAST SIDE OF THIS UPPER COLD POCKET. THIS SHOULD CLEAR OUT ANY PRECIP OVER THE CWA FROM NW TO SE...OVER THE NEXT 3 TO 6 HOURS. SOME PATCHY FOG STILL PSBL LATER TONIGHT WHERE THE WINDS MAY BE LIGHTEST OVER SE CORNER OF CWA. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 28 53 33 66 / 20 0 0 0 MLU 28 48 29 65 / 20 0 0 0 DEQ 21 46 27 63 / 20 0 0 0 TXK 26 48 32 64 / 20 0 0 0 ELD 26 47 28 64 / 20 0 0 0 TYR 27 56 38 68 / 20 0 0 0 GGG 27 55 34 67 / 20 0 0 0 LFK 28 58 34 71 / 20 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 17/24
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1011 PM EST FRI MAR 7 2008 .UPDATE... THE 00Z DTX SOUNDING SHOWED A FAIRLY SIGNIFICANT DRY LAYER BETWEEN 850MB AND 750MB...WITH A SHALLOW MOIST LAYER BELOW AN 875MB INVERSION. NORTHEAST FLOW OFF LAKE HURON AIDED THE DEVELOPMENT OF THIS SHALLOW MOIST LAYER. AS THIS MOIST LAYER WORKED INTO A LITTLE DEEPER MOISTURE AROUND THE DETROIT AREA THIS EVENING...SNOWFALL RAPIDLY DEVELOPED. THE LIFT AND DEEPER MOISTURE HAS BEEN TIED TO SOME MID TROPOSPHERIC DEFORMATION ORIENTED ALONG A TOLEDO TO PORT HURON AXIS. THIS DEFORMATION IS FORECAST TO PERSIST THROUGH THE NIGHT. NORTH TO NORTHEASTERLY LOW LEVEL WINDS HOWEVER WILL CONTINUE TO FILTER DRY AIR INTO SE MI /THE 00Z APX SOUNDING HAD A PRECIPITABLE WATER VALUE OF ONLY 0.06 IN/. THUS EXPECT THERE WILL CONTINUE TO BE A SHARP CUT OFF IN SNOWFALL HEADING NORTHWEST INTO THE FORECAST AREA. THE MORE PERSIST SNOWFALL WILL AFFECT LOCATIONS IN MONROE COUNTY...ALONG THE DETROIT RIVER IN WAYNE COUNTY...AND ACROSS HARSONS ISLAND AND ALGONAC IN SOUTHERN ST CLAIR COUNTY. 1 TO 3 INCHES OF ACCUMULATION SEEMS LIKELY IN THESE AREAS...WITH LITTLE ACCUMULATION ACROSS THE REST OF THE FORECAST AREA. OVERALL THE CURRENT FORECAST HAS THIS HANDLED WELL. WILL JUST UPDATE TO REMOVE POPS IN THE TRI CITIES AND BACK OFF THE CHANCE OF SNOW TO FLURRIES ACROSS THE FLINT AND THUMB REGION. THE CURRENT SNOW AND BLOWING SNOW ADVISORY FOR THE SOUTHEASTERN 1/3RD OF THE FORECAST AREA STILL LOOKS REASONABLE FOR SATURDAY. BASED ON SURFACE PRESSURE FALLS...THE SURFACE LOW NEAR ATLANTA GA LOOKS LIKE IT WILL HEAD TO THE EAST OF THE APPALACHIANS. THIS ALONG WITH THE FACT THAT THE UPPER WAVE OVER THE GULF COAST HAS STILL NOT DEVELOPED A NEGATIVE TILT SUPPORTS SE MI RECEIVING THE FAR WESTERN EDGE OF THE DEFORMATION SNOWS ONGOING ACROSS THE LOWER OHIO VALLEY. && .PREV DISCUSSION...ISSUED 628 PM EST FRI MAR 7 2008 AVIATION... THE WINTER STORM CURRENTLY IMPACTING THE OHIO VALLEY WILL REMAIN A CONCERN FOR THE DETROIT TERMINALS TONIGHT THROUGH THE DAY SATURDAY. A 21Z TAMDAR SOUNDING OUT OF DTW SHOWED PLENTY OF LOW LEVEL DRY AIR IN PLACE. AREA RADAR AND SURFACE OBSERVATIONS STILL HOWEVER SHOW A SLIGHTLY NORTHWARD TREND TO THE SNOW ACROSS NE OHIO. SURFACE DEWPOINTS ARE ALSO BEGINNING TO RISE IN THE METRO DETROIT AREA. WITH KTOL STILL NOT REPORTING ANY SNOW...AND BASED ON 18Z MODEL GUIDANCE...WILL HOLD OFF MENTIONING MVFR CONDITIONS IN LIGHT SNOW IN THE DETROIT AREA UNTIL AFTER 06Z. WITH THE STORM SYSTEM LIFTING ACROSS THE EASTERN US ON SATURDAY...STRONGER LIFT WILL BRUSH SE MI AFTER 12Z. THIS WILL BRING PERSISTENT IFR CONDITIONS IN SNOW TO THE DETROIT AREA. AS FOR FNT AND MBS...MOISTURE FLUX OFF LAKE HURON COMBINED WITH SOME DIURNAL ENHANCEMENT HAS LED TO SOME MVFR CEILINGS AND FLURRIES IN THE FLINT AREA. THESE SHOULD SUBSIDE WITHIN THE NEXT COUPLE OF HOURS WITH THE LOSS OF SOLAR INSOLATION. OTHERWISE...PLAN TO MAINTAIN SOME MVFR CONDITIONS IN LIGHT SNOW AT FNT AFTER 11Z...WHILE MAINTAINING VFR CONDITIONS AT MBS. NORTH-NORTHEAST WINDS WILL REMAIN SUSTAINED AT 10 TO 15 KNOTS THROUGH THE PERIOD...WITH GUSTS INCREASING ABOVE 25 KNOTS AFTER 12Z SAT FOR ALL TAF SITES. PREV DISCUSSION...ISSUED 423 PM EST FRI MAR 7 2008 SHORT TERM...THIS AFTERNOON AND TONIGHT THE FORECAST CENTERS ON THE TIMING AND AMOUNTS OF SNOWFALL FOR THE WINTER STORM IMPACTING THE OHIO RIVER VALLEY. THE LARGE PARTITIONED FULL LATITUDE TROUGH LYING ACROSS A LARGE PORTION OF CENTRAL NORTH AMERICA HAS BEEN ORGANIZING THIS AFTERNOON AS SOUTHERN ENERGY ATOP TEXAS WORKS THROUGH THE BASE. THE ASSOCIATED SURFACE LOW...CURRENTLY ANCHORED OVER FAR WESTERN VIRGINIA AND NORTHEASTERN TENNESSEE...IS ALREADY A LITTLE NORTH AND WEST OF 12Z MODEL SOLUTIONS. THE 12Z SUITE DID FALL IN LINE WITH THE EARLIER MODELS SOLUTIONS IN DEPICTING A SURFACE LOW TRACK EAST OF THE APPALACHIAN SPINE. HOWEVER...STILL DIFFICULT TO BITE ON A COMPLETE EASTERN TRACK GIVEN THE LATEST OBSERVATIONAL DATA. FOR TONIGHT...THE LARGE MIDLEVEL WAVE CURRENTLY DROPPING SOUTHWARD INTO KANSAS/OKLAHOMA WILL HESITATE AS A STRONG UPPER LEVEL JET STREAK WORKS OUT OF THE TROUGH BASE. THE TROPOPAUSE UNDULATION WILL LIFT OUT ALLOWING FOR THE NEGATIVE TILT. EARLIER ANALYSIS OF THE MODEL INITIALIZATIONS REVEALED A SLIGHT UNDER REPRESENTATION IN THE STRENGTH OF THE THE LARGE UPPER LEVEL TROUGH (WATER VAPOR IMAGERY CERTAINLY SUPPORTS A STRONGER SYSTEM). MODEL QPF (12Z GFS/18Z NAM/NGM) IS IN FAIR AGREEMENT PAINTING .1 TO .2 OF INCH FOR THE SOUTHEASTERN PORTION OF THE FORECAST AREA TONIGHT. LOOKING AT CROSS SECTIONS...THE POTENTIAL FOR BANDING WILL BE GREATEST TO OUR SOUTHEAST. EXPECTATIONS ARE FOR FAR EASTERN ST CLAIR/MACOMB/WAYNE/MONROE COUNTIES TO ACCUMULATE CLOSE TO 2 INCHES BY TOMORROW MORNING....TAPERING OFF TO AN INCH ACROSS THE REST OF THE ADVISORY COUNTIES. WINDS WILL STEADILY INCREASE OVERNIGHT AS THE SURFACE LOW STRENGTHENS. CROSS SECTIONS AND MODEL SOUNDINGS HINT AT FAIRLY STABLE LOW LEVELS...SO THE GUSTS MAY WAIT CLOSER TO THE MORNING. THIS EVENT IS A HIGHLY TOUCHY FORECAST WITH QPF AND SNOW AMOUNTS. THERE IS EXPECTED TO BE A SHARP GRADIENT ONCE AGAIN WITH GREATER THAN 6 INCHES OF SNOWFALL JUST TO THE EAST. THEREFORE...FLUCTUATIONS IN THE STORM TRACK WILL HAVE A MAJOR IMPACT ON THE TOTAL SNOW AMOUNTS. LOWS ARE MAINLY FROM INHERITED WITH A SLIGHT ADJUSTMENT UPWARD WITH THE CLOUD COVER. LONG TERM...SATURDAY THROUGH FRIDAY DEFORMATION SNOW WILL CONTINUE TO PUSH NORTHWESTWARD DURING THE MORNING AS THE 700MB AND 500MB TRACK ACROSS CENTRAL OHIO. NGM/GFS/NAM/GLBLGEM ALL IN GOOD AGREEMENT WITH BRINGING MEASURABLE SNOW BACK TO ABOUT A HOWELL TO LAPEER TO SANDUSKY LINE DURING THE MORNING BEFORE PULLING OFF TO THE EAST DURING THE LATE AFTERNOON. THE QPF IS ALSO IN GOOD AGREEMENT WITH ABOUT A TENTH REACHING THE NORTHERN EXTENT WHICH WOULD LEAD TO AROUND AN INCH OF SNOW...UP TO THREE TENTHS ALONG THE EASTERN EDGE OF THE FORECAST AREA WHICH WOULD GIVE AROUND 4 INCHES. BLOWING SNOW AND DRIFTING WILL ALSO BE A PROBLEM FOR THE AREAS RECEIVING SNOW AS IT WILL BE A DRY FLUFFY SNOW AS ATMOSPHERE WILL BE QUITE COLD. WINDS WILL BE STRONG DURING THE DAY AS THE ASSOCIATED SURFACE LOW IS FORECAST TO DEEPEN AS IT MOVES UP THE EAST SIDE OF THE APPALACHIANS WHILE ARCTIC HIGH PRESSURE HANGS TOUGH OVER THE WESTERN LAKES. EXPECTING A COLD NORTH WIND OF 15 TO 25 MPH WITH GUSTS TO AROUND 30 MPH. AS THE ARCTIC HIGH SITS TO THE NORTH...TEMPERATURES WILL ONLY REACH THE LOW TO MID 20S WITH WIND CHILLS REMAINING IN THE SINGLE DIGITS TO SUBZERO. MODELS ALL KEEP BEST LIFT AND MOISTURE JUST TO THE EAST OF THE CWA. ANY SLIGHT ADJUSTMENT OF STORM TRACK TO THE WEST COULD EASILY BRING SEVERAL MORE INCHES OF SNOW...ESPECIALLY TO THE EASTERN FRINGE OF THE FORECAST AREA. AT PRESS TIME...CURRENT WATERVAPOR AND SURFACE PRESSURE PLOTS SEEM TO BE A BIT STRONGER AND SLIGHTLY FURTHER WEST THEN MODELS INDICATE AS THE MAIN PLAYER...SECONDARY SHORTWAVE DROPPING DOWN THROUGH OKLAHOMA PHASES WITH SOUTHERN STREAM WAVE OVER ARKANSAS. THIS COULD LEAD TO A MORE WESTWARD TRACK. EVENING AND NIGHT CREW WILL DO A FINE JOB MONITORING THIS AND MAKING ANY ADJUSTMENTS IF NEED BE. BEYOND SATURDAY A SUSTAINED UPPER NORTHWEST FLOW WILL BRING A FEW WEAK CLIPPER SYSTEMS TO THE GREAT LAKES. ONE WILL MOVE ACROSS NORTHERN INDIANA AND OHIO LATE SUNDAY/SUNDAY NIGHT. AT THIS POINT...LOOKS LIKE SOME LIGHT SNOW POSSIBLE ACROSS SOUTHERN HALF OF CWA WITH MAYBE A DUSTING NEAR THE SOUTHERN BORDER. ANOTHER SYSTEM WILL CROSS THE NORTHERN LAKES TUESDAY BRINGING ANOTHER CHANCE OF RAIN/SNOW ACROSS THE SAGINAW VALLEY AND THUMB. UPPER RIDGE WILL BUILD IN FOR THE MIDDLE OF THE WEEK BRINGING A QUICK SHOT OF MORE NORMAL TEMPERATURES FOR THIS TIME OF MARCH BEFORE ANOTHER ARCTIC FRONT DRIVES A COLD FRONT THROUGH THURSDAY WITH CHANCE OF RAIN THURSDAY FOLLOWED BY BELOW NORMAL TEMPS AND SNOW SHOWERS FOR FRI. MARINE... NORTHERLY WINDS WILL STEADILY INCREASE TONIGHT AND SATURDAY AS A STRONG LOW PRESSURE SYSTEM TRACKS UP THE EASTERN UNITED STATES. WINDS WILL GUSTS TO 25 KNOTS OVERNIGHT...THEN A PERIOD OF FREQUENT GUSTS TO GALE FORCE IS EXPECTED SATURDAY ACROSS SOUTHERN LAKE HURON...LAKE ST CLAIR...AND LAKE ERIE. IN ADDITION TO THE WIND...THE COLD AIR OFF THE NORTH SHORE OF LAKE HURON...THE COLD WATER...AND THE STRONG WINDS WILL ALL COMBINE TO PRODUCE A RISK OF FREEZING SPRAY. THIS WILL ESPECIALLY BE THE CASE TONIGHT AS TEMPERATURES DROP TO ZERO OR BELOW IN ONTARIO NORTH OF THE LAKE AND WITH WATER TEMPERATURE SO CLOSE TO FREEZING. THESE HARSH MARINE CONDITIONS WILL EASE BY SUNDAY AS THE SYSTEM OFF THE ATLANTIC COAST CONTINUES TO MOVE AWAY FROM THE AREA. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...SNOW AND BLOWING SNOW ADVISORY...MIZ063-MIZ069-MIZ070-MIZ075-MIZ076- MIZ082-MIZ083...UNTIL 7 PM SATURDAY. LAKE HURON... HEAVY FREEZING SPRAY WARNING...LHZ362-LHZ363-LHZ462-LHZ463- LHZ464...UNTIL 7 PM SATURDAY. BRISK WIND ADVISORY...SAGINAW BAY...UNTIL 7 PM SATURDAY. BRISK WIND ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON...UNTIL 10 AM SATURDAY. GALE WARNING...LHZ441-LHZ442-LHZ443-LHZ462-LHZ463-LHZ464...FROM 10 AM SATURDAY TO 7 PM SATURDAY. LAKE ST CLAIR... BRISK WIND ADVISORY...UNTIL 10 AM SATURDAY. GALE WARNING...FROM 10 AM SATURDAY TO 7 PM SATURDAY. MI WATERS OF LAKE ERIE... BRISK WIND ADVISORY...UNTIL 10 AM SATURDAY. GALE WARNING...FROM 10 AM SATURDAY TO 7 PM SATURDAY. && $$ UPDATE.......SC AVIATION.....SC SHORT TERM...CB LONG TERM....DRC MARINE.......JDS YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
628 PM EST FRI MAR 7 2008 .AVIATION... THE WINTER STORM CURRENTLY IMPACTING THE OHIO VALLEY WILL REMAIN A CONCERN FOR THE DETROIT TERMINALS TONIGHT THROUGH THE DAY SATURDAY. A 21Z TAMDAR SOUNDING OUT OF DTW SHOWED PLENTY OF LOW LEVEL DRY AIR IN PLACE. AREA RADAR AND SURFACE OBSERVATIONS STILL HOWEVER SHOW A SLIGHTLY NORTHWARD TREND TO THE SNOW ACROSS NE OHIO. SURFACE DEWPOINTS ARE ALSO BEGINNING TO RISE IN THE METRO DETROIT AREA. WITH KTOL STILL NOT REPORTING ANY SNOW...AND BASED ON 18Z MODEL GUIDANCE...WILL HOLD OFF MENTIONING MVFR CONDITIONS IN LIGHT SNOW IN THE DETROIT AREA UNTIL AFTER 06Z. WITH THE STORM SYSTEM LIFTING ACROSS THE EASTERN US ON SATURDAY...STRONGER LIFT WILL BRUSH SE MI AFTER 12Z. THIS WILL BRING PERSISTENT IFR CONDITIONS IN SNOW TO THE DETROIT AREA. AS FOR FNT AND MBS...MOISTURE FLUX OFF LAKE HURON COMBINED WITH SOME DIURNAL ENHANCEMENT HAS LED TO SOME MVFR CEILINGS AND FLURRIES IN THE FLINT AREA. THESE SHOULD SUBSIDE WITHIN THE NEXT COUPLE OF HOURS WITH THE LOSS OF SOLAR INSOLATION. OTHERWISE...PLAN TO MAINTAIN SOME MVFR CONDITIONS IN LIGHT SNOW AT FNT AFTER 11Z...WHILE MAINTAINING VFR CONDITIONS AT MBS. NORTH-NORTHEAST WINDS WILL REMAIN SUSTAINED AT 10 TO 15 KNOTS THROUGH THE PERIOD...WITH GUSTS INCREASING ABOVE 25 KNOTS AFTER 12Z SAT FOR ALL TAF SITES. && .PREV DISCUSSION...ISSUED 423 PM EST FRI MAR 7 2008 SHORT TERM...THIS AFTERNOON AND TONIGHT THE FORECAST CENTERS ON THE TIMING AND AMOUNTS OF SNOWFALL FOR THE WINTER STORM IMPACTING THE OHIO RIVER VALLEY. THE LARGE PARTITIONED FULL LATITUDE TROUGH LYING ACROSS A LARGE PORTION OF CENTRAL NORTH AMERICA HAS BEEN ORGANIZING THIS AFTERNOON AS SOUTHERN ENERGY ATOP TEXAS WORKS THROUGH THE BASE. THE ASSOCIATED SURFACE LOW...CURRENTLY ANCHORED OVER FAR WESTERN VIRGINIA AND NORTHEASTERN TENNESSEE...IS ALREADY A LITTLE NORTH AND WEST OF 12Z MODEL SOLUTIONS. THE 12Z SUITE DID FALL IN LINE WITH THE EARLIER MODELS SOLUTIONS IN DEPICTING A SURFACE LOW TRACK EAST OF THE APPALACHIAN SPINE. HOWEVER...STILL DIFFICULT TO BITE ON A COMPLETE EASTERN TRACK GIVEN THE LATEST OBSERVATIONAL DATA. FOR TONIGHT...THE LARGE MIDLEVEL WAVE CURRENTLY DROPPING SOUTHWARD INTO KANSAS/OKLAHOMA WILL HESITATE AS A STRONG UPPER LEVEL JET STREAK WORKS OUT OF THE TROUGH BASE. THE TROPOPAUSE UNDULATION WILL LIFT OUT ALLOWING FOR THE NEGATIVE TILT. EARLIER ANALYSIS OF THE MODEL INITIALIZATIONS REVEALED A SLIGHT UNDER REPRESENTATION IN THE STRENGTH OF THE THE LARGE UPPER LEVEL TROUGH (WATER VAPOR IMAGERY CERTAINLY SUPPORTS A STRONGER SYSTEM). MODEL QPF (12Z GFS/18Z NAM/NGM) IS IN FAIR AGREEMENT PAINTING .1 TO .2 OF INCH FOR THE SOUTHEASTERN PORTION OF THE FORECAST AREA TONIGHT. LOOKING AT CROSS SECTIONS...THE POTENTIAL FOR BANDING WILL BE GREATEST TO OUR SOUTHEAST. EXPECTATIONS ARE FOR FAR EASTERN ST CLAIR/MACOMB/WAYNE/MONROE COUNTIES TO ACCUMULATE CLOSE TO 2 INCHES BY TOMORROW MORNING....TAPERING OFF TO AN INCH ACROSS THE REST OF THE ADVISORY COUNTIES. WINDS WILL STEADILY INCREASE OVERNIGHT AS THE SURFACE LOW STRENGTHENS. CROSS SECTIONS AND MODEL SOUNDINGS HINT AT FAIRLY STABLE LOW LEVELS...SO THE GUSTS MAY WAIT CLOSER TO THE MORNING. THIS EVENT IS A HIGHLY TOUCHY FORECAST WITH QPF AND SNOW AMOUNTS. THERE IS EXPECTED TO BE A SHARP GRADIENT ONCE AGAIN WITH GREATER THAN 6 INCHES OF SNOWFALL JUST TO THE EAST. THEREFORE...FLUCTUATIONS IN THE STORM TRACK WILL HAVE A MAJOR IMPACT ON THE TOTAL SNOW AMOUNTS. LOWS ARE MAINLY FROM INHERITED WITH A SLIGHT ADJUSTMENT UPWARD WITH THE CLOUD COVER. LONG TERM...SATURDAY THROUGH FRIDAY DEFORMATION SNOW WILL CONTINUE TO PUSH NORTHWESTWARD DURING THE MORNING AS THE 700MB AND 500MB TRACK ACROSS CENTRAL OHIO. NGM/GFS/NAM/GLBLGEM ALL IN GOOD AGREEMENT WITH BRINGING MEASURABLE SNOW BACK TO ABOUT A HOWELL TO LAPEER TO SANDUSKY LINE DURING THE MORNING BEFORE PULLING OFF TO THE EAST DURING THE LATE AFTERNOON. THE QPF IS ALSO IN GOOD AGREEMENT WITH ABOUT A TENTH REACHING THE NORTHERN EXTENT WHICH WOULD LEAD TO AROUND AN INCH OF SNOW...UP TO THREE TENTHS ALONG THE EASTERN EDGE OF THE FORECAST AREA WHICH WOULD GIVE AROUND 4 INCHES. BLOWING SNOW AND DRIFTING WILL ALSO BE A PROBLEM FOR THE AREAS RECEIVING SNOW AS IT WILL BE A DRY FLUFFY SNOW AS ATMOSPHERE WILL BE QUITE COLD. WINDS WILL BE STRONG DURING THE DAY AS THE ASSOCIATED SURFACE LOW IS FORECAST TO DEEPEN AS IT MOVES UP THE EAST SIDE OF THE APPALACHIANS WHILE ARCTIC HIGH PRESSURE HANGS TOUGH OVER THE WESTERN LAKES. EXPECTING A COLD NORTH WIND OF 15 TO 25 MPH WITH GUSTS TO AROUND 30 MPH. AS THE ARCTIC HIGH SITS TO THE NORTH...TEMPERATURES WILL ONLY REACH THE LOW TO MID 20S WITH WIND CHILLS REMAINING IN THE SINGLE DIGITS TO SUBZERO. MODELS ALL KEEP BEST LIFT AND MOISTURE JUST TO THE EAST OF THE CWA. ANY SLIGHT ADJUSTMENT OF STORM TRACK TO THE WEST COULD EASILY BRING SEVERAL MORE INCHES OF SNOW...ESPECIALLY TO THE EASTERN FRINGE OF THE FORECAST AREA. AT PRESS TIME...CURRENT WATERVAPOR AND SURFACE PRESSURE PLOTS SEEM TO BE A BIT STRONGER AND SLIGHTLY FURTHER WEST THEN MODELS INDICATE AS THE MAIN PLAYER...SECONDARY SHORTWAVE DROPPING DOWN THROUGH OKLAHOMA PHASES WITH SOUTHERN STREAM WAVE OVER ARKANSAS. THIS COULD LEAD TO A MORE WESTWARD TRACK. EVENING AND NIGHT CREW WILL DO A FINE JOB MONITORING THIS AND MAKING ANY ADJUSTMENTS IF NEED BE. BEYOND SATURDAY A SUSTAINED UPPER NORTHWEST FLOW WILL BRING A FEW WEAK CLIPPER SYSTEMS TO THE GREAT LAKES. ONE WILL MOVE ACROSS NORTHERN INDIANA AND OHIO LATE SUNDAY/SUNDAY NIGHT. AT THIS POINT...LOOKS LIKE SOME LIGHT SNOW POSSIBLE ACROSS SOUTHERN HALF OF CWA WITH MAYBE A DUSTING NEAR THE SOUTHERN BORDER. ANOTHER SYSTEM WILL CROSS THE NORTHERN LAKES TUESDAY BRINGING ANOTHER CHANCE OF RAIN/SNOW ACROSS THE SAGINAW VALLEY AND THUMB. UPPER RIDGE WILL BUILD IN FOR THE MIDDLE OF THE WEEK BRINGING A QUICK SHOT OF MORE NORMAL TEMPERATURES FOR THIS TIME OF MARCH BEFORE ANOTHER ARCTIC FRONT DRIVES A COLD FRONT THROUGH THURSDAY WITH CHANCE OF RAIN THURSDAY FOLLOWED BY BELOW NORMAL TEMPS AND SNOW SHOWERS FOR FRI. MARINE... NORTHERLY WINDS WILL STEADILY INCREASE TONIGHT AND SATURDAY AS A STRONG LOW PRESSURE SYSTEM TRACKS UP THE EASTERN UNITED STATES. WINDS WILL GUSTS TO 25 KNOTS OVERNIGHT...THEN A PERIOD OF FREQUENT GUSTS TO GALE FORCE IS EXPECTED SATURDAY ACROSS SOUTHERN LAKE HURON...LAKE ST CLAIR...AND LAKE ERIE. IN ADDITION TO THE WIND...THE COLD AIR OFF THE NORTH SHORE OF LAKE HURON...THE COLD WATER...AND THE STRONG WINDS WILL ALL COMBINE TO PRODUCE A RISK OF FREEZING SPRAY. THIS WILL ESPECIALLY BE THE CASE TONIGHT AS TEMPERATURES DROP TO ZERO OR BELOW IN ONTARIO NORTH OF THE LAKE AND WITH WATER TEMPERATURE SO CLOSE TO FREEZING. THESE HARSH MARINE CONDITIONS WILL EASE BY SUNDAY AS THE SYSTEM OFF THE ATLANTIC COAST CONTINUES TO MOVE AWAY FROM THE AREA. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...SNOW AND BLOWING SNOW ADVISORY...MIZ063-MIZ069-MIZ070-MIZ075-MIZ076- MIZ082-MIZ083...FROM MIDNIGHT SATURDAY TO 7 PM SATURDAY. LAKE HURON... HEAVY FREEZING SPRAY WARNING...LHZ362-LHZ363-LHZ462-LHZ463- LHZ464...UNTIL 7 PM SATURDAY. BRISK WIND ADVISORY...SAGINAW BAY...UNTIL 7 PM SATURDAY. BRISK WIND ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON...UNTIL 10 AM SATURDAY. GALE WARNING...LHZ441-LHZ442-LHZ443-LHZ462-LHZ463-LHZ464...FROM 10 AM SATURDAY TO 7 PM SATURDAY. LAKE ST CLAIR... BRISK WIND ADVISORY...UNTIL 10 AM SATURDAY. GALE WARNING...FROM 10 AM SATURDAY TO 7 PM SATURDAY. MI WATERS OF LAKE ERIE... BRISK WIND ADVISORY...UNTIL 10 AM SATURDAY. GALE WARNING...FROM 10 AM SATURDAY TO 7 PM SATURDAY. && $$ AVIATION.....SC SHORT TERM...CB LONG TERM....DRC MARINE.......JDS YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1005 AM EST SAT MAR 8 2008 .SYNOPSIS... LOW PRESSURE MOVING INTO NORTHEAST PENNSYLVANIA LATE TODAY WILL BRING A MIXED BAG OF PRECIPITATION TO THE REGION. AS THE LOW MOVES INTO NEW ENGLAND TONIGHT, RAIN AND MIXED PRECIPITATION WILL CHANGE OVER TO SNOW SHOWERS AS GUSTY WINDS BRING IN COLDER AIR. THE SNOW SHOWERS WILL PERSIST ACROSS UPSTATE NEW YORK ON SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... UPDATED...LTL CHG TO CRNT FCST AND WILL LEAVE ALL FLAGS AS IS. AREAS ALONG AND W OF I-81 HAVE SFC TEMPS GNRLY IN THE 30-32 RNG, AND XPCT LTL CHG THIS AFTN. ACRS THESE AREAS, A MIX OF RAIN/FZRA AND SLEET CAN BE XPCTD. AREAS TO THE SE WILL SEE RAIN AS THE PRIMARY PCPN TYPE. POTNL FOR CONVECTION THIS AFTN ACRS THE POCONOS AND SRN CATSKILLS MAY POSE SOME FLASHY HYDRO PRBLMS THIS AFTN/EVNG AND WILL KEEP A CLOSE EYE ON THIS. WINDS WILL PICK UP THIS EVNG BEHIND THE LOW. ISALLOBARIC FIELD LOOKS PRETTY GOOD BUT INITIAL BUFKIT PROFILES SUGGEST LOW END ADVISORY. IN AGREEMENT WITH BUF/ALY TO HOLD OFF ON ANY WIND HEADLINES ATTM...INITIAL THOUGHT IS THAT 20-30G4O WOULD WORK FOR MOST OF THE AREA. GIVEN COMPLEXITY OF FCST ATTM WILL LEAVE HEADLINES AS IS BUT WILL CONSIDER WIND HEADLINES THIS AFTN. PREV BLO... WK SFC LOW THAT DEVELOPED OVR THE DELMARVA EARLY THIS MRNG HAS MVD TO A POSN OFF OF CAPE COD. THIS HAS SERVED TO PULL IN A LITTLE BIT CLDR AIR FOR THE TIME BEING BUT HAS ALSO TAKEN PCPN WITH IT AS IT EXITS. RESPITE FROM THE PCPN WILL BE SHORT-LIVED AS MORE IS MVG QUICKLY NORTH THRU PA WITH LIGHTNING STRIKES ALREADY NOTED OVR CPA. UPPER LOW HAS CLOSED OFF OVR THE TN VALLEY WITH ASSOC SFC LOW MAKING RAPID PROGRESS TO THE NORTH...CURRENTLY LOCATED OVR VA/TN/NC BORDER. SFC TROF AXIS EXTENDS NORTH OF THE CTR AND TWD FA WITH GREATEST PRESSURE FALLS OVR WV AT PRESENT. EXPECT THIS LOW WILL CONTINUE MVG NORTH AND EAST TODAY ALONG BOUNDARY. BOTH NAM/GFS ARE IN GOOD AGREEMENT ON EVENTUAL POSN OF LOW THIS AFTN. ONLY DIFFERENCE RMNS IN THE NAM DEVELOPING SECONDARY LOW ALONG THE COAST THIS AFTN. HOWEVER...WITHIN 6 HRS THE PRIMARILY SFC LOW TAKES OVR. GFS/SUPER ENSEMBLES/RUC DO NOT SEEM TO BE BUYING INTO THIS SOLN AND HAVE THUS SIDED TWD GFS SOLN IN THE PLACEMENT OF THE LOW CTR FOR TODAY. H5 LOW WILL EJECT NORTH TODAY AS NEXT S/WV DROPS INTO NRN PLAINS AND KICKS IT OUT. LOW IS PROGGED TO TAKE ON NEGATIVE TILT AS IT HEADS UP INTO THE OH VALLEY. ALL SHORT AND MEDIUM RANGE GUIDANCE INDICATES THE LOW CTR TRACKING WEST OF THE FA TODAY. H8/H7 CENTERS ALSO EXPECTED TO TRACK THRU WRN NY/FINGER LAKES TODAY. AS H8 LOW TRACKS NORTH...WINDS WILL BACK ARND TO THE SOUTHEAST DRAWING WARMER AIR INTO CNY AFTR ABOUT 15Z. CURRENTLY TEMPS ARE SITTING RIGHT ARND FZG. INITIAL BATCH OF PCPN WILL MV IN BTWN 12Z-15Z. BUFKIT PROFILES FROM THE NAM/GFS/RUC INDICATE A MIX OF SLEET OR FZRA EARLY THIS MRNG...POSSIBLY MIXED WITH SNOW ACROSS THE FAR NORTH AS PROFILE RMNS ISOTHERMAL PER ACARS DATA. AS WARM ADVECTION KICKS IN THE WARM LAYER AT 800MB INCRS TO ARND +5C. FAR SRN AND ERN ZONES WILL RMN ABV FRZG AND EXPECT ALL RAIN TODAY. SOME ELEVATED CONVECTION CAN BE EXPECTED WITH SHOWALTERS DROPPING BLO ZERO AND LAPSE RATES INCRSG TO 6.5-7 FROM 15Z-21Z. FURTHER NORTH...SLEET AND FREEZING RAIN WILL GIVE WAY TO ALL RAIN AFTER ABOUT 15Z ACROSS PARTS OF CNY. HIGHER ELEVATIONS MAY RMN ARND FRZG FOR A GOOD PART OF THE DAY. WITH TEMPS ARND 32F...PCPN MAY HAVE A HARD TIME ACCUMULATING ON SFCS AND EXPECT ICING OF ONLY ONE TENTH OF AN INCH OR SO THRU THE DAY ACROSS THE HILLTOPS. ACROSS THE FINGER LAKES AND FAR NORTH...FREEZING RAIN MAY HOLD ON A LITTLE LONGER AS TEMPS WILL STRUGGLE INTO THE MIDDLE 30S. UP TO ONE QUARTER OF AN INCH WILL BE POSSIBLE ALTHO VALLEY LOCATIONS SHUD WARM UP ENUF TO SEE PLAIN RAIN. THUS...HAVE LEFT WINTER WX ADVISORIES IN PLACE WHERE THEY PREVIOUSLY WERE. DELAWARE COUNTY MAY BE A QUESTION MARK AS TO WHETHER SOME SPOTS MAY SEE SOME ICING BUT HAVE OPTED NOT TO INCLUDE THEM AS OF YET AS MOST OF THE COUNTY SHUD WARM UP FAIRLY QUICKLY ALOFT. WINTER STORM WARNINGS FOR STEUBEN...SCHUYLER... MADISON AND SRN ONEIDA HAVE BEEN DROPPED TO WINTER WX ADVISORIES. VRY LITTLE SNOW IS EXPECTED TODAY AND ICING AMNTS WILL NOT BE ENUF TO PUSH THESE AREAS TO WARNING CRITERIA. REGARDING THE HEAVY RAIN THREAT...H8 JET INCREASES TO 40-50KTS THIS AFTN WITH A SOUTH-SOUTHEAST TRAJECTORY AS H8 LOW MVS NORTH. THIS IN CONJUNCTION WITH SRN STREAM SPEED MAX AND POSSIBLE ELEVATED CONVECTION WILL CONTINUE THE THREAT FOR FLOODING TODAY. CUD SEE SOME URBAN AND SMALL STREAM FLOODING BUT FEEL THE BETTER CHC FOR HVY RAIN HAS SHIFTED A LITTLE TO THE EAST BASED ON TRACK OF SFC LOW AND H8 SPEED MAX. MODELS HV COME IN LIGHTER ON QPF WITH 0.50-1.00 INCHES EXPECTED FROM I-81 CORRIDOR EAST. WITH RIVERS STILL HIGH AND PROGGED TO RISE TO NR/ABV FLOOD STAGE ON THE SUSQUEHANNA AND DELAWARE BEST COURSE OF ACTION IS TO KEEP FLOOD WATCH GOING THRU SUNDAY MORNING. LATER SHIFTS MAY NEED TO CANCEL IT EARLY GIVEN PROGRESS OF HVY RAIN TO THE EAST. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... FCST FOR TONIGHT COMPLICATED WITH REGARD TO SNOWFALL AMNTS/WARNING CRITERIA PCPN. SFC LOW PASSES THRU THIS EVENING AND DRAWS COLD AIR IN VRY QUICKLY. TEMPS ALOFT PLUMMET BHND THE STORM WITH H8 TEMPS DOWN TO NR -15C AFTER 06Z. PCPN WILL CHG TO ALL SNOW OVR MOST OF CNY AFTER 00Z. QPF FROM 00Z NAM/GFS BOTH GIVE ABOUT ONE HALF INCH ACROSS THE FINGER LKS/MOHAWK VALLEY OVERNIGHT. TREMENDOUS LIFT BEING ADVERTISED ALONG WITH RAPIDLY LOWERING SNOW GROWTH LAYER. INITIAL PLAN WAS TO DROP WARNING FOR THE ENTIRE AREA. HOWEVER...WRAP- ROUND OCCASIONALLY HAS A TENDENCY TO INTENSIFY DUE TO THE LAKE INFLUENCE. WITH FAVORABLE SNOW GROWTH AREA...INTENSE LIFT AND PLENTY OF MOISTURE AVAILABLE OVR NRN SECTIONS...HAVE OPTED TO KEEP WARNING GOING FROM YATES THRU ONONDAGA AND NRN ONEIDA. THE BEST CHC FOR 12-HR WARNING CRITERIA ACCUMS WILL BE FROM PENN YAN TO SYRACUSE TO BOONVILLE WITH 5-8 INCHES POSSIBLE. LIMITING FACTOR IN ALL THIS WILL BE THE SPEED AT WHICH THE STORM DEPARTS THE AREA. PCPN WILL ONLY HV ABOUT A 4-6 HR WINDOW TO WORK WITH IN ORDER TO GET WARNING CRITERIA. THE ADVISORY AREA WILL ONLY SEE ABOUT 1-3 INCHES OF SNOW ACCUMS OVRNGT BUT SLEET AND FZRA EXPECTED SAT AFTN WARRANTS KEEPING HEADLINE RUNNING. NEXT CONCERN FOR TONIGHT WILL BE WINDS BHND THE STORM. TIGHT PRESSURE GRADIENT WILL EXIST ARND LOW AS IT CONTINUES TO DEEPEN INTO NRN VT. MODELS HINTING AT H8 WINDS OF 50KTS BLOWING THRU ON BACKSIDE OF SFC LOW. WUD NOT BE SURPRISED TO SEE GUSTS UP TO 45 KTS OVERNIGHT OVR THE HILLTOPS. WIND ADVISORY MAY NEED TO BE HOISTED LATER ON. FOR THE TIME BEING...PREFER TO CVR POTENTIAL IN SUBSEQUENT WINTER WX HEADLINES AND THE HWO. AREAS OF SNOW AND BLOWING SNOW CAN BE EXPECTED TONIGHT - ONE MORE FACTOR IN FAVOR OF KEEPING SOME PORTIONS OF THE WINTER STORM WARNING GOING. THE SNOW SHUD BEGIN TO TAPER OFF AFTER MIDNIGHT AS LOW RAPIDLY MVS NORTH AND EAST. LAKE EFFECT SNOW SHOWERS WILL BE POSSIBLE ON SUNDAY BUT CONDS DO NOT APPEAR TO BE FAVORABLE FOR ADVISORY ACCUMS WITH THE SNOWS. LAKE EFFECT WILL SLOWLY COME TO AN END ON MONDAY AS HIPRES TRIES TO BUILD IN. && .LONG TERM /TUESDAY THROUGH FRIDAY/... WITH FOCUS ON THE SHORT TERM MIXED EVENT ABOUT TO GET UNDERWAY... WE HAVE FOLLOWED THE HPC GUIDANCE WITH THIS FCST UPDATE. IN GENERAL...MED RANGE MODELS SUGGEST THAT THE NORTHERN STREAM WILL INFLUENCE WX ACROSS CNY/NEPA WITH TRANSIENT WEAK SYSTEMS PASSING THROUGH THE AREA. NOTHING AT THIS TIME LOOKS SIGNIFICANT. COLD ENOUGH FOR CHC SOME LAKE EFFECT SNOW SHOWERS LINGERING SUN NITE AND MONDAY. LACK OF SYNOPTIC MOISTURE SHOULD MAKE ANY LES A LIGHT EVENT. WEAK TROF/FRONT PASSAGES TUESDAY NIGHT AND THURSDAY NIGHT INTO FRIDAY WITH CHANCES FOR SNOW SHOWERS AT NIGHT...RAIN SHOWERS DURING THE DAY. HIGH PRESSURE AND DRY CONDITIONS TUESDAY AND WEDS INTO THURS. TEMPS START OFF BELOW NORMAL...THEN DECENT WAA AHEAD OF FRONT THURSDAY NIGHT AND FRIDAY SHOULD BRING TEMPS ABOVE. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... PRECIP MOVING BACK INTO ALL TAF SITES THIS MORNING. CONDITIONS WILL BE A CHALLENGE, BOTH FOR FLYING AND FOR FORECASTING. WILL LIKELY SEE AN AVERAGE OF IFR CONDITIONS TODAY, ALTHOUGH FLUCTUATIONS ON EITHER SIDE ARE EXPECTED. LOWEST CONDITIONS LIKELY AT HIGHER ELEVATIONS OF KBGM AND KITH WHERE LIFR WILL BE COMMON. A MIX OF PRECIP THIS MORNING AT KSYR, KITH, KELM, KBGM...CHANGING TO ALL RAIN BY LATE THIS MORNING. AT KAVP, ALL RAIN...BUT THERE ARE A FEW TSRA TO THE SOUTH AND WEST OF THE STATION, SO HAVE INCLUDED A CB GROUP FOR A FEW HOURS THIS MORNING. PRECIP CHANGES OVER TO SNOW THIS EVENING AND TAPERS OFF, WITH GENERAL IMPROVEMENT TO MVFR, AND POSSIBLY EVEN VFR DURING THE OVERNIGHT. NORTH TO NORTHEAST WINDS TODAY, 10 KTS OR LESS...WILL INCREASE OUT OF THE NORTHWEST TONIGHT, 15 TO 25 KTS WITH GUSTS TO 30 KTS. OUTLOOK... SUN...VFR. NO SIG WX. MON...VFR. NO SIG WX. TUES...MVFR...CHC SNOW SHOWERS. WED...VFR. NO SIG WX. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...FLOOD WATCH THROUGH SUNDAY MORNING FOR PAZ038>040-043-044-047- 048-072. WINTER WEATHER ADVISORY UNTIL 8 AM EDT SUNDAY FOR PAZ038-039. NY...FLOOD WATCH THROUGH SUNDAY MORNING FOR NYZ009-037-045-046- 055>057-062. WINTER WEATHER ADVISORY UNTIL 8 AM EDT SUNDAY FOR NYZ022>025- 036-037-044>046-055-056. WINTER STORM WARNING UNTIL 8 AM EDT SUNDAY FOR NYZ009-015>018. && $$ SYNOPSIS...PVB NEAR TERM...PVB SHORT TERM...PVB LONG TERM...JAB AVIATION...JML/TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
638 AM EST SAT MAR 8 2008 .SYNOPSIS... A STORM SYSTEM MOVING UP FROM THE TENNESSEE VALLEY WILL SPREAD A MIX OF SLEET AND FREEZING RAIN INTO CENTRAL NEW YORK THIS MORNING...WITH RAIN EXPECTED OVER NORTHEAST PENNSYLVANIA. AS WARM AIR GETS WRAPPED UP AROUND THE STORM THE MIXED PRECIPITATION IS EXPECTED TO SWITCH OVER TO ALL RAIN BY NOON. SOME HIGHER HILLTOP LOCATIONS MAY EXPERIENCE FREEZING RAIN OFF AND ON THROUGH THE AFTERNOON AS TEMPERATURES HOVER AROUND FREEZING. THE RAIN WILL CHANGE OVER TO SNOW THIS EVENING BEGINNING IN THE FINGER LAKES...AND WORKING SOUTH OVERNIGHT. SNOW ACCUMULATIONS OF 5 TO 8 INCHES WILL BE POSSIBLE OVER PORTIONS OF THE FINGER LAKES TONIGHT...WITH SEVERAL INCHES EXPECTED ACROSS THE SOUTHERN TIER AND SUSQUEHANNA BASIN. NORTHWEST WINDS WILL STRENGTHEN TONIGHT WITH WIND GUSTS OF 35 TO 45 MPH POSSIBLE. THE SNOW WILL TAPER OFF BY MORNING...WITH ONLY A FEW LINGER LAKE EFFECT SNOW SHOWERS EXPECTED EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... WK SFC LOW THAT DEVELOPED OVR THE DELMARVA EARLY THIS MRNG HAS MVD TO A POSN OFF OF CAPE COD. THIS HAS SERVED TO PULL IN A LITTLE BIT CLDR AIR FOR THE TIME BEING BUT HAS ALSO TAKEN PCPN WITH IT AS IT EXITS. RESPITE FROM THE PCPN WILL BE SHORT-LIVED AS MORE IS MVG QUICKLY NORTH THRU PA WITH LIGHTNING STRIKES ALREADY NOTED OVR CPA. UPPER LOW HAS CLOSED OFF OVR THE TN VALLEY WITH ASSOC SFC LOW MAKING RAPID PROGRESS TO THE NORTH...CURRENTLY LOCATED OVR VA/TN/NC BORDER. SFC TROF AXIS EXTENDS NORTH OF THE CTR AND TWD FA WITH GREATEST PRESSURE FALLS OVR WV AT PRESENT. EXPECT THIS LOW WILL CONTINUE MVG NORTH AND EAST TODAY ALONG BOUNDARY. BOTH NAM/GFS ARE IN GOOD AGREEMENT ON EVENTUAL POSN OF LOW THIS AFTN. ONLY DIFFERENCE RMNS IN THE NAM DEVELOPING SECONDARY LOW ALONG THE COAST THIS AFTN. HOWEVER...WITHIN 6 HRS THE PRIMARILY SFC LOW TAKES OVR. GFS/SUPER ENSEMBLES/RUC DO NOT SEEM TO BE BUYING INTO THIS SOLN AND HAVE THUS SIDED TWD GFS SOLN IN THE PLACEMENT OF THE LOW CTR FOR TODAY. H5 LOW WILL EJECT NORTH TODAY AS NEXT S/WV DROPS INTO NRN PLAINS AND KICKS IT OUT. LOW IS PROGGED TO TAKE ON NEGATIVE TILT AS IT HEADS UP INTO THE OH VALLEY. ALL SHORT AND MEDIUM RANGE GUIDANCE INDICATES THE LOW CTR TRACKING WEST OF THE FA TODAY. H8/H7 CENTERS ALSO EXPECTED TO TRACK THRU WRN NY/FINGER LAKES TODAY. AS H8 LOW TRACKS NORTH...WINDS WILL BACK ARND TO THE SOUTHEAST DRAWING WARMER AIR INTO CNY AFTR ABOUT 15Z. CURRENTLY TEMPS ARE SITTING RIGHT ARND FZG. INITIAL BATCH OF PCPN WILL MV IN BTWN 12Z-15Z. BUFKIT PROFILES FROM THE NAM/GFS/RUC INDICATE A MIX OF SLEET OR FZRA EARLY THIS MRNG...POSSIBLY MIXED WITH SNOW ACROSS THE FAR NORTH AS PROFILE RMNS ISOTHERMAL PER ACARS DATA. AS WARM ADVECTION KICKS IN THE WARM LAYER AT 800MB INCRS TO ARND +5C. FAR SRN AND ERN ZONES WILL RMN ABV FRZG AND EXPECT ALL RAIN TODAY. SOME ELEVATED CONVECTION CAN BE EXPECTED WITH SHOWALTERS DROPPING BLO ZERO AND LAPSE RATES INCRSG TO 6.5-7 FROM 15Z-21Z. FURTHER NORTH...SLEET AND FREEZING RAIN WILL GIVE WAY TO ALL RAIN AFTER ABOUT 15Z ACROSS PARTS OF CNY. HIGHER ELEVATIONS MAY RMN ARND FRZG FOR A GOOD PART OF THE DAY. WITH TEMPS ARND 32F...PCPN MAY HAVE A HARD TIME ACCUMULATING ON SFCS AND EXPECT ICING OF ONLY ONE TENTH OF AN INCH OR SO THRU THE DAY ACROSS THE HILLTOPS. ACROSS THE FINGER LAKES AND FAR NORTH...FREEZING RAIN MAY HOLD ON A LITTLE LONGER AS TEMPS WILL STRUGGLE INTO THE MIDDLE 30S. UP TO ONE QUARTER OF AN INCH WILL BE POSSIBLE ALTHO VALLEY LOCATIONS SHUD WARM UP ENUF TO SEE PLAIN RAIN. THUS...HAVE LEFT WINTER WX ADVISORIES IN PLACE WHERE THEY PREVIOUSLY WERE. DELAWARE COUNTY MAY BE A QUESTION MARK AS TO WHETHER SOME SPOTS MAY SEE SOME ICING BUT HAVE OPTED NOT TO INCLUDE THEM AS OF YET AS MOST OF THE COUNTY SHUD WARM UP FAIRLY QUICKLY ALOFT. WINTER STORM WARNINGS FOR STEUBEN...SCHUYLER... MADISON AND SRN ONEIDA HAVE BEEN DROPPED TO WINTER WX ADVISORIES. VRY LITTLE SNOW IS EXPECTED TODAY AND ICING AMNTS WILL NOT BE ENUF TO PUSH THESE AREAS TO WARNING CRITERIA. REGARDING THE HEAVY RAIN THREAT...H8 JET INCREASES TO 40-50KTS THIS AFTN WITH A SOUTH-SOUTHEAST TRAJECTORY AS H8 LOW MVS NORTH. THIS IN CONJUNCTION WITH SRN STREAM SPEED MAX AND POSSIBLE ELEVATED CONVECTION WILL CONTINUE THE THREAT FOR FLOODING TODAY. CUD SEE SOME URBAN AND SMALL STREAM FLOODING BUT FEEL THE BETTER CHC FOR HVY RAIN HAS SHIFTED A LITTLE TO THE EAST BASED ON TRACK OF SFC LOW AND H8 SPEED MAX. MODELS HV COME IN LIGHTER ON QPF WITH 0.50-1.00 INCHES EXPECTED FROM I-81 CORRIDOR EAST. WITH RIVERS STILL HIGH AND PROGGED TO RISE TO NR/ABV FLOOD STAGE ON THE SUSQUEHANNA AND DELAWARE BEST COURSE OF ACTION IS TO KEEP FLOOD WATCH GOING THRU SUNDAY MORNING. LATER SHIFTS MAY NEED TO CANCEL IT EARLY GIVEN PROGRESS OF HVY RAIN TO THE EAST. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... FCST FOR TONIGHT COMPLICATED WITH REGARD TO SNOWFALL AMNTS/WARNING CRITERIA PCPN. SFC LOW PASSES THRU THIS EVENING AND DRAWS COLD AIR IN VRY QUICKLY. TEMPS ALOFT PLUMMET BHND THE STORM WITH H8 TEMPS DOWN TO NR -15C AFTER 06Z. PCPN WILL CHG TO ALL SNOW OVR MOST OF CNY AFTER 00Z. QPF FROM 00Z NAM/GFS BOTH GIVE ABOUT ONE HALF INCH ACROSS THE FINGER LKS/MOHAWK VALLEY OVERNIGHT. TREMENDOUS LIFT BEING ADVERTISED ALONG WITH RAPIDLY LOWERING SNOW GROWTH LAYER. INITIAL PLAN WAS TO DROP WARNING FOR THE ENTIRE AREA. HOWEVER...WRAP- ROUND OCCASIONALLY HAS A TENDENCY TO INTENSIFY DUE TO THE LAKE INFLUENCE. WITH FAVORABLE SNOW GROWTH AREA...INTENSE LIFT AND PLENTY OF MOISTURE AVAILABLE OVR NRN SECTIONS...HAVE OPTED TO KEEP WARNING GOING FROM YATES THRU ONONDAGA AND NRN ONEIDA. THE BEST CHC FOR 12-HR WARNING CRITERIA ACCUMS WILL BE FROM PENN YAN TO SYRACUSE TO BOONVILLE WITH 5-8 INCHES POSSIBLE. LIMITING FACTOR IN ALL THIS WILL BE THE SPEED AT WHICH THE STORM DEPARTS THE AREA. PCPN WILL ONLY HV ABOUT A 4-6 HR WINDOW TO WORK WITH IN ORDER TO GET WARNING CRITERIA. THE ADVISORY AREA WILL ONLY SEE ABOUT 1-3 INCHES OF SNOW ACCUMS OVRNGT BUT SLEET AND FZRA EXPECTED SAT AFTN WARRANTS KEEPING HEADLINE RUNNING. NEXT CONCERN FOR TONIGHT WILL BE WINDS BHND THE STORM. TIGHT PRESSURE GRADIENT WILL EXIST ARND LOW AS IT CONTINUES TO DEEPEN INTO NRN VT. MODELS HINTING AT H8 WINDS OF 50KTS BLOWING THRU ON BACKSIDE OF SFC LOW. WUD NOT BE SURPRISED TO SEE GUSTS UP TO 45 KTS OVERNIGHT OVR THE HILLTOPS. WIND ADVISORY MAY NEED TO BE HOISTED LATER ON. FOR THE TIME BEING...PREFER TO CVR POTENTIAL IN SUBSEQUENT WINTER WX HEADLINES AND THE HWO. AREAS OF SNOW AND BLOWING SNOW CAN BE EXPECTED TONIGHT - ONE MORE FACTOR IN FAVOR OF KEEPING SOME PORTIONS OF THE WINTER STORM WARNING GOING. THE SNOW SHUD BEGIN TO TAPER OFF AFTER MIDNIGHT AS LOW RAPIDLY MVS NORTH AND EAST. LAKE EFFECT SNOW SHOWERS WILL BE POSSIBLE ON SUNDAY BUT CONDS DO NOT APPEAR TO BE FAVORABLE FOR ADVISORY ACCUMS WITH THE SNOWS. LAKE EFFECT WILL SLOWLY COME TO AN END ON MONDAY AS HIPRES TRIES TO BUILD IN. && .LONG TERM /TUESDAY THROUGH FRIDAY/... WITH FOCUS ON THE SHORT TERM MIXED EVENT ABOUT TO GET UNDERWAY... WE HAVE FOLLOWED THE HPC GUIDANCE WITH THIS FCST UPDATE. IN GENERAL...MED RANGE MODELS SUGGEST THAT THE NORTHERN STREAM WILL INFLUENCE WX ACROSS CNY/NEPA WITH TRANSIENT WEAK SYSTEMS PASSING THROUGH THE AREA. NOTHING AT THIS TIME LOOKS SIGNIFICANT. COLD ENOUGH FOR CHC SOME LAKE EFFECT SNOW SHOWERS LINGERING SUN NITE AND MONDAY. LACK OF SYNOPTIC MOISTURE SHOULD MAKE ANY LES A LIGHT EVENT. WEAK TROF/FRONT PASSAGES TUESDAY NIGHT AND THURSDAY NIGHT INTO FRIDAY WITH CHANCES FOR SNOW SHOWERS AT NIGHT...RAIN SHOWERS DURING THE DAY. HIGH PRESSURE AND DRY CONDITIONS TUESDAY AND WEDS INTO THURS. TEMPS START OFF BELOW NORMAL...THEN DECENT WAA AHEAD OF FRONT THURSDAY NIGHT AND FRIDAY SHOULD BRING TEMPS ABOVE. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... PRECIP MOVING BACK INTO ALL TAF SITES THIS MORNING. CONDITIONS WILL BE A CHALLENGE, BOTH FOR FLYING AND FOR FORECASTING. WILL LIKELY SEE AN AVERAGE OF IFR CONDITIONS TODAY, ALTHOUGH FLUCTUATIONS ON EITHER SIDE ARE EXPECTED. LOWEST CONDITIONS LIKELY AT HIGHER ELEVATIONS OF KBGM AND KITH WHERE LIFR WILL BE COMMON. A MIX OF PRECIP THIS MORNING AT KSYR, KITH, KELM, KBGM...CHANGING TO ALL RAIN BY LATE THIS MORNING. AT KAVP, ALL RAIN...BUT THERE ARE A FEW TSRA TO THE SOUTH AND WEST OF THE STATION, SO HAVE INCLUDED A CB GROUP FOR A FEW HOURS THIS MORNING. PRECIP CHANGES OVER TO SNOW THIS EVENING AND TAPERS OFF, WITH GENERAL IMPROVEMENT TO MVFR, AND POSSIBLY EVEN VFR DURING THE OVERNIGHT. NORTH TO NORTHEAST WINDS TODAY, 10 KTS OR LESS...WILL INCREASE OUT OF THE NORTHWEST TONIGHT, 15 TO 25 KTS WITH GUSTS TO 30 KTS. OUTLOOK... SUN...VFR. NO SIG WX. MON...VFR. NO SIG WX. TUES...MVFR...CHC SNOW SHOWERS. WED...VFR. NO SIG WX. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...FLOOD WATCH THROUGH SUNDAY MORNING FOR PAZ038>040-043-044-047- 048-072. WINTER WEATHER ADVISORY UNTIL 8 AM EDT SUNDAY FOR PAZ038-039. NY...FLOOD WATCH THROUGH SUNDAY MORNING FOR NYZ009-037-045-046- 055>057-062. WINTER WEATHER ADVISORY UNTIL 8 AM EDT SUNDAY FOR NYZ022>025- 036-037-044>046-055-056. WINTER STORM WARNING UNTIL 8 AM EDT SUNDAY FOR NYZ009-015>018. && $$ SYNOPSIS...PVB NEAR TERM...PVB SHORT TERM...PVB LONG TERM...JAB AVIATION...JML/TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
539 AM EST SAT MAR 8 2008 .SYNOPSIS... A STORM SYSTEM MOVING UP FROM THE TENNESSEE VALLEY WILL SPREAD A MIX OF SLEET AND FREEZING RAIN INTO CENTRAL NEW YORK THIS MORNING...WITH RAIN EXPECTED OVER NORTHEAST PENNSYLVANIA. AS WARM AIR GETS WRAPPED UP AROUND THE STORM THE MIXED PRECIPITATION IS EXPECTED TO SWITCH OVER TO ALL RAIN BY NOON. SOME HIGHER HILLTOP LOCATIONS MAY EXPERIENCE FREEZING RAIN OFF AND ON THROUGH THE AFTERNOON AS TEMPERATURES HOVER AROUND FREEZING. THE RAIN WILL CHANGE OVER TO SNOW THIS EVENING BEGINNING IN THE FINGER LAKES...AND WORKING SOUTH OVERNIGHT. SNOW ACCUMULATIONS OF 5 TO 8 INCHES WILL BE POSSIBLE OVER PORTIONS OF THE FINGER LAKES TONIGHT...WITH SEVERAL INCHES EXPECTED ACROSS THE SOUTHERN TIER AND SUSQUEHANNA BASIN. NORTHWEST WINDS WILL STRENGTHEN TONIGHT WITH WIND GUSTS OF 35 TO 45 MPH POSSIBLE. THE SNOW WILL TAPER OFF BY MORNING...WITH ONLY A FEW LINGER LAKE EFFECT SNOW SHOWERS EXPECTED EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WK SFC LOW THAT DEVELOPED OVR THE DELMARVA EARLY THIS MRNG HAS MVD TO A POSN OFF OF CAPE COD. THIS HAS SERVED TO PULL IN A LITTLE BIT CLDR AIR FOR THE TIME BEING BUT HAS ALSO TAKEN PCPN WITH IT AS IT EXITS. RESPITE FROM THE PCPN WILL BE SHORT-LIVED AS MORE IS MVG QUICKLY NORTH THRU PA WITH LIGHTNING STRIKES ALREADY NOTED OVR CPA. UPPER LOW HAS CLOSED OFF OVR THE TN VALLEY WITH ASSOC SFC LOW MAKING RAPID PROGRESS TO THE NORTH...CURRENTLY LOCATED OVR VA/TN/NC BORDER. SFC TROF AXIS EXTENDS NORTH OF THE CTR AND TWD FA WITH GREATEST PRESSURE FALLS OVR WV AT PRESENT. EXPECT THIS LOW WILL CONTINUE MVG NORTH AND EAST TODAY ALONG BOUNDARY. BOTH NAM/GFS ARE IN GOOD AGREEMENT ON EVENTUAL POSN OF LOW THIS AFTN. ONLY DIFFERENCE RMNS IN THE NAM DEVELOPING SECONDARY LOW ALONG THE COAST THIS AFTN. HOWEVER...WITHIN 6 HRS THE PRIMARILY SFC LOW TAKES OVR. GFS/SUPER ENSEMBLES/RUC DO NOT SEEM TO BE BUYING INTO THIS SOLN AND HAVE THUS SIDED TWD GFS SOLN IN THE PLACEMENT OF THE LOW CTR FOR TODAY. H5 LOW WILL EJECT NORTH TODAY AS NEXT S/WV DROPS INTO NRN PLAINS AND KICKS IT OUT. LOW IS PROGGED TO TAKE ON NEGATIVE TILT AS IT HEADS UP INTO THE OH VALLEY. ALL SHORT AND MEDIUM RANGE GUIDANCE INDICATES THE LOW CTR TRACKING WEST OF THE FA TODAY. H8/H7 CENTERS ALSO EXPECTED TO TRACK THRU WRN NY/FINGER LAKES TODAY. AS H8 LOW TRACKS NORTH...WINDS WILL BACK ARND TO THE SOUTHEAST DRAWING WARMER AIR INTO CNY AFTR ABOUT 15Z. CURRENTLY TEMPS ARE SITTING RIGHT ARND FZG. INITIAL BATCH OF PCPN WILL MV IN BTWN 12Z-15Z. BUFKIT PROFILES FROM THE NAM/GFS/RUC INDICATE A MIX OF SLEET OR FZRA EARLY THIS MRNG...POSSIBLY MIXED WITH SNOW ACROSS THE FAR NORTH AS PROFILE RMNS ISOTHERMAL PER ACARS DATA. AS WARM ADVECTION KICKS IN THE WARM LAYER AT 800MB INCRS TO ARND +5C. FAR SRN AND ERN ZONES WILL RMN ABV FRZG AND EXPECT ALL RAIN TODAY. SOME ELEVATED CONVECTION CAN BE EXPECTED WITH SHOWALTERS DROPPING BLO ZERO AND LAPSE RATES INCRSG TO 6.5-7 FROM 15Z-21Z. FURTHER NORTH...SLEET AND FREEZING RAIN WILL GIVE WAY TO ALL RAIN AFTER ABOUT 15Z ACROSS PARTS OF CNY. HIGHER ELEVATIONS MAY RMN ARND FRZG FOR A GOOD PART OF THE DAY. WITH TEMPS ARND 32F...PCPN MAY HAVE A HARD TIME ACCUMULATING ON SFCS AND EXPECT ICING OF ONLY ONE TENTH OF AN INCH OR SO THRU THE DAY ACROSS THE HILLTOPS. ACROSS THE FINGER LAKES AND FAR NORTH...FREEZING RAIN MAY HOLD ON A LITTLE LONGER AS TEMPS WILL STRUGGLE INTO THE MIDDLE 30S. UP TO ONE QUARTER OF AN INCH WILL BE POSSIBLE ALTHO VALLEY LOCATIONS SHUD WARM UP ENUF TO SEE PLAIN RAIN. THUS...HAVE LEFT WINTER WX ADVISORIES IN PLACE WHERE THEY PREVIOUSLY WERE. DELAWARE COUNTY MAY BE A QUESTION MARK AS TO WHETHER SOME SPOTS MAY SEE SOME ICING BUT HAVE OPTED NOT TO INCLUDE THEM AS OF YET AS MOST OF THE COUNTY SHUD WARM UP FAIRLY QUICKLY ALOFT. WINTER STORM WARNINGS FOR STEUBEN...SCHUYLER... MADISON AND SRN ONEIDA HAVE BEEN DROPPED TO WINTER WX ADVISORIES. VRY LITTLE SNOW IS EXPECTED TODAY AND ICING AMNTS WILL NOT BE ENUF TO PUSH THESE AREAS TO WARNING CRITERIA. REGARDING THE HEAVY RAIN THREAT...H8 JET INCREASES TO 40-50KTS THIS AFTN WITH A SOUTH-SOUTHEAST TRAJECTORY AS H8 LOW MVS NORTH. THIS IN CONJUNCTION WITH SRN STREAM SPEED MAX AND POSSIBLE ELEVATED CONVECTION WILL CONTINUE THE THREAT FOR FLOODING TODAY. CUD SEE SOME URBAN AND SMALL STREAM FLOODING BUT FEEL THE BETTER CHC FOR HVY RAIN HAS SHIFTED A LITTLE TO THE EAST BASED ON TRACK OF SFC LOW AND H8 SPEED MAX. MODELS HV COME IN LIGHTER ON QPF WITH 0.50-1.00 INCHES EXPECTED FROM I-81 CORRIDOR EAST. WITH RIVERS STILL HIGH AND PROGGED TO RISE TO NR/ABV FLOOD STAGE ON THE SUSQUEHANNA AND DELAWARE BEST COURSE OF ACTION IS TO KEEP FLOOD WATCH GOING THRU SUNDAY MORNING. LATER SHIFTS MAY NEED TO CANCEL IT EARLY GIVEN PROGRESS OF HVY RAIN TO THE EAST. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/... FCST FOR TONIGHT COMPLICATED WITH REGARD TO SNOWFALL AMNTS/WARNING CRITERIA PCPN. SFC LOW PASSES THRU THIS EVENING AND DRAWS COLD AIR IN VRY QUICKLY. TEMPS ALOFT PLUMMET BHND THE STORM WITH H8 TEMPS DOWN TO NR -15C AFTER 06Z. PCPN WILL CHG TO ALL SNOW OVR MOST OF CNY AFTER 00Z. QPF FROM 00Z NAM/GFS BOTH GIVE ABOUT ONE HALF INCH ACROSS THE FINGER LKS/MOHAWK VALLEY OVERNIGHT. TREMENDOUS LIFT BEING ADVERTISED ALONG WITH RAPIDLY LOWERING SNOW GROWTH LAYER. INITIAL PLAN WAS TO DROP WARNING FOR THE ENTIRE AREA. HOWEVER...WRAP- ROUND OCCASIONALLY HAS A TENDENCY TO INTENSIFY DUE TO THE LAKE INFLUENCE. WITH FAVORABLE SNOW GROWTH AREA...INTENSE LIFT AND PLENTY OF MOISTURE AVAILABLE OVR NRN SECTIONS...HAVE OPTED TO KEEP WARNING GOING FROM YATES THRU ONONDAGA AND NRN ONEIDA. THE BEST CHC FOR 12-HR WARNING CRITERIA ACCUMS WILL BE FROM PENN YAN TO SYRACUSE TO BOONVILLE WITH 5-8 INCHES POSSIBLE. LIMITING FACTOR IN ALL THIS WILL BE THE SPEED AT WHICH THE STORM DEPARTS THE AREA. PCPN WILL ONLY HV ABOUT A 4-6 HR WINDOW TO WORK WITH IN ORDER TO GET WARNING CRITERIA. THE ADVISORY AREA WILL ONLY SEE ABOUT 1-3 INCHES OF SNOW ACCUMS OVRNGT BUT SLEET AND FZRA EXPECTED SAT AFTN WARRANTS KEEPING HEADLINE RUNNING. NEXT CONCERN FOR TONIGHT WILL BE WINDS BHND THE STORM. TIGHT PRESSURE GRADIENT WILL EXIST ARND LOW AS IT CONTINUES TO DEEPEN INTO NRN VT. MODELS HINTING AT H8 WINDS OF 50KTS BLOWING THRU ON BACKSIDE OF SFC LOW. WUD NOT BE SURPRISED TO SEE GUSTS UP TO 45 KTS OVERNIGHT OVR THE HILLTOPS. WIND ADVISORY MAY NEED TO BE HOISTED LATER ON. FOR THE TIME BEING...PREFER TO CVR POTENTIAL IN SUBSEQUENT WINTER WX HEADLINES AND THE HWO. AREAS OF SNOW AND BLOWING SNOW CAN BE EXPECTED TONIGHT - ONE MORE FACTOR IN FAVOR OF KEEPING SOME PORTIONS OF THE WINTER STORM WARNING GOING. THE SNOW SHUD BEGIN TO TAPER OFF AFTER MIDNIGHT AS LOW RAPIDLY MVS NORTH AND EAST. LAKE EFFECT SNOW SHOWERS WILL BE POSSIBLE ON SUNDAY BUT CONDS DO NOT APPEAR TO BE FAVORABLE FOR ADVISORY ACCUMS WITH THE SNOWS. LAKE EFFECT WILL SLOWLY COME TO AN END ON MONDAY AS HIPRES TRIES TO BUILD IN. && .LONG TERM /TUESDAY THROUGH FRIDAY/... WITH FOCUS ON THE SHORT TERM MIXED EVENT ABOUT TO GET UNDERWAY... WE HAVE FOLLOWED THE HPC GUIDANCE WITH THIS FCST UPDATE. IN GENERAL...MED RANGE MODELS SUGGEST THAT THE NORTHERN STREAM WILL INFLUENCE WX ACROSS CNY/NEPA WITH TRANSIENT WEAK SYSTEMS PASSING THROUGH THE AREA. NOTHING AT THIS TIME LOOKS SIGNIFICANT. COLD ENOUGH FOR CHC SOME LAKE EFFECT SNOW SHOWERS LINGERING SUN NITE AND MONDAY. LACK OF SYNOPTIC MOISTURE SHOULD MAKE ANY LES A LIGHT EVENT. WEAK TROF/FRONT PASSAGES TUESDAY NIGHT AND THURSDAY NIGHT INTO FRIDAY WITH CHANCES FOR SNOW SHOWERS AT NIGHT...RAIN SHOWERS DURING THE DAY. HIGH PRESSURE AND DRY CONDITIONS TUESDAY AND WEDS INTO THURS. TEMPS START OFF BELOW NORMAL...THEN DECENT WAA AHEAD OF FRONT THURSDAY NIGHT AND FRIDAY SHOULD BRING TEMPS ABOVE. && .AVIATION /10Z SATURDAY THROUGH WEDNESDAY/... ALTHOUGH MOST OF THE FIRST BATCH OF PRECIP FROM CURRENT STORM SYSTEM HAS TAPERED OFF, SPOTTY DRIZZLE AND PLENTY OF LOW LEVEL MOISTURE WILL LEAVE LOW CONDITIONS THROUGH THE NIGHT BEFORE ARRIVAL OF MORE STEADY PRECIP. A WIDE VARIETY OF CEILINGS AND VISBY THROUGH THE NIGHT...ANYTHING FROM MVFR TO VLIFR...ESPECIALLY AT HIGHER ELEV SITES OF KITH AND KBGM. THEREFORE HAVE PLENTY OF TEMPO GROUPS IN THE FIRST SEVERAL HOURS OF THE TAFS. NEXT BATCH OF PRECIP LOOKS LIKE IT WILL MOVE IN AROUND MID MORNING TODAY...WITH MORE LOW CEILINGS AND VISBYS. PRECIPITATION TYPE WILL CONTINUE TO FLUCTUATE WITH THIS SYSTEM. LOOKING FOR ELM- SYR- RME TO HAVE MAJORITY OF TIME IN WINTRY MIX. LATEST GUIDANCE INDICATES LIKELIHOOD OF SIGNIFICANT FZRA AT ELM...WITH MORE OF A SNOW/SLEET SITUATION AT SYR- RME -ITH...ALTHOUGH THESE STATIONS WILL ALSO HAVE A PERIOD OF -FZRA MAINLY THIS MORNING. BGM WILL BE MOST TRANSITORY...DOMINATED MAINLY BY RAIN/FZRA...AND AVP WILL REMAIN RAIN. OUTLOOK... SAT NITE...IFR/MVFR BECOMING VFR. SNOW DIMINISHING. LAKE EFFECT SHSN MAY LINGER SYR-RME. SUN...VFR. NO SIG WX. MON...VFR. NO SIG WX. TUES...MVFR...CHC SNOW SHOWERS. WEDS...VFR. NO SIG WX. && .HYDROLOGY... QPF EXPECTED TO RANGE FROM 0.50-1.00 INCHES TODAY WITH LOCALLY HIGHER AMNTS APPCHG 1.50 INCHES OVR THE DELAWARE RIVER BASIN. RIVERS CONTINUE TO RISE AND MANY WILL APPCH MINOR FLOOD STAGE THIS WEEKEND. UPDATED RIVER STATEMENTS ARE OUT AND WILL BE UPDATED LATER THIS MORNING. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...FLOOD WATCH THROUGH SUNDAY MORNING FOR PAZ038>040-043-044-047- 048-072. WINTER WEATHER ADVISORY UNTIL 8 AM EDT SUNDAY FOR PAZ038-039. NY...FLOOD WATCH THROUGH SUNDAY MORNING FOR NYZ009-037-045-046- 055>057-062. WINTER WEATHER ADVISORY UNTIL 8 AM EDT SUNDAY FOR NYZ022>025- 036-037-044>046-055-056. WINTER STORM WARNING UNTIL 8 AM EDT SUNDAY FOR NYZ009-015>018. && $$ SYNOPSIS...PVB NEAR TERM...PVB SHORT TERM...PVB LONG TERM...JAB AVIATION...JML/TAC