Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/26/16


AREA FORECAST DISCUSSION
NWS ALBANY NY
414 PM EST WED FEB 24 2016 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL PASS WEST OF THE REGION THIS EVENING INTO TONIGHT...ALLOWING FOR PERIODS OF RAIN AND ISOLATED THUNDERSTORMS. ANY THUNDERSTORM WILL BE CAPABLE OF PRODUCING LOCALLY STRONG WIND GUSTS. TEMPERATURES WILL CONTINUE TO RISE TONIGHT...REACHING MILD LEVELS FOR TOMORROW MORNING...WITH SHOWERS ENDING. COOLER TEMPEARTURES AND A FEW PASSING SNOW SHOWERS AND FLURRIES WILL RETURN ON FRIDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 413 PM EST...A LARGE AND DYNAMIC STORM SYSTEM IS LOCATED OVER THE OHIO VALLEY...WITH A WARM FRONT EXTENDING ACROSS THE MID ATLANTIC STATES. PERIODS OF LIGHT RAIN HAVE BEEN ONGOING ACROSS OUR AREA TODAY...AND THIS LOOKS TO CONTINUE FOR THE NEXT FEW HOURS. WITH THIS STORM EXPECTED TO PASS TO OUR WEST THIS EVENING INTO TONIGHT...A STRONG SOUTHERLY FLOW WILL BE IN PLACE AT LOW AND MID LEVELS...WITH 850 HPA WINDS EXCEEDING 70 KTS THIS EVENING. THESE 850 V WINDS ARE 3-4 STD ABOVE NORMAL. IN ADDITION...THIS STRONG SOUTHERLY FLOW IS ALLOWING FOR PWATS TO RISE TO 3-4 STD ABOVE NORMAL AS WELL. WE HAVE ISSUED A WIND ADVISORY FOR NW CT...AS THE STRONG WINDS ALOFT MAY BE ABLE TO MIX DOWN TO THE SFC IF IT CAN BREAK THE STRONG LOW LEVEL INVERSION IN PLACE...AND THE MOST LIKELY PLACE FOR THIS TO OCCUR WOULD BE IN NW CT. REGIONAL MOSAIC RADAR SHOWS A LINE OF SEVERE T-STORMS OVER VIRGINA/NORTH CAROLINA AHEAD OF THE STORM/S OCCLUDED FRONT. AS THIS WHOLE STORM SYSTEM LIFTS NORTHEAST TOWARDS THE EASTERN GREAT LAKES...THIS BAND OF STORMS WILL MOVE NORTHEAST AS WELL AS THE STORM/S OCCLUDED FRONT LIFTS NORTHEAST. THE 3KM HRRR SHOWS THAT WHAT/S LEFT OF THIS LINE COULD BE MOVING TOWARDS OUR AREA FOR LATE THIS EVENING...GENERALLY BETWEEN 00Z-06Z. THE ENVIRONMENT IS MUCH DIFFERENT HERE THAN OVER THE MID ATLANTIC...AS COOL LOW LEVEL TEMPS AND A STRONG LOW LEVEL INVERSION WILL KEEP INSTABILITY RATHER LOW AND HELP PREVENT THE WORST OF THE WINDS FROM MIXING DOWN. ANY CONVECTIVE ELEMENTS PRESENT WILL LIKELY BE ELEVATED. STILL...CANNOT RULE OUT SOME LOCALIZED STRONG TO SEVERE WIND GUSTS FROM MIXING DOWN IN PLACES WHERE THE INVERSION CAN BE BROKEN...AND SPC HAS MOST OF OUR AREA IN A MARGINAL RISK FOR SEVERE WEATHER. TEMPS ARE CURRENTLY MAINLY IN THE 30S...ALTHOUGH A FEW SPOTS ACROSS WESTERN NEW ENGLAND HAVE WARMED INTO THE 40S THANKS TO EASTERLY FLOW DOWNSLOPING OFF THE HIGH TERRAIN. AS WE GET TOWARDS THE WARM SECTOR...THE SOUTHERLY FLOW COULD HELP TEMPS SPIKE TONIGHT INTO THE 40S AND 50S...WHICH COULD HELP WEAKEN THAT LOW LEVEL INVERSION AS WELL. IN ADDITION TO THE THREAT FOR GUSTY WINDS...RAIN WILL BE MODERATE TO LOCALLY HEAVY AHEAD OF THE STORM/S OCCLUDED FRONT. A GENERAL ONE TO TWO INCHES IS EXPECTED OVER THE AREA...SEE OUR HYDRO DISCUSSION BELOW FOR HOW WE EXPECT THIS RAINFALL TO IMPACT OUR HSA. THE STEADIEST RAINFALL WILL BE TAPERING OFF BY 08Z-09Z /ACCORDING TO THE HIRES GUIDANCE/. CANNOT RULED OUT SOME LINGERING RAIN SHOWERS BEHIND THE OCCLUDED BOUNDARY THANKS TO THE UPPER LEVEL TROUGH MOVING THROUGH...BUT THE HEAVIEST RAIN WILL CERTAINLY BE DONE BY THAT TIME. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... THURSDAY WILL CONTINUE TO FEATURE MILD TEMPS TO START THE DAY...BUT THE UPPER LEVEL TROUGH MOVING OVER THE REGION...TEMPS ALOFT WILL START TO COOL OFF. THIS WILL HELP TEMPS START TO FALL BACK DOWN FOR THE AFTERNOON HOURS. IT LOOKS TO REMAIN CLOUDY WITH THE CYCLONIC FLOW IN PLACE...AND THERE COULD BE SOME ADDITIONAL RAIN SHOWERS...ESP FOR WESTERN/NORTHERN AREAS. TEMPS WILL FALL THROUGH THE 40S IN THE AFTN HOURS...AND REACH THE MID TO UPPER 30S OVER THE HIGHER ELEVATIONS BY LATE IN THE DAY. TEMPS WILL CONTINUE TO FALL INTO THE TEENS AND 20S FOR THURSDAY NIGHT...AS 850 HPA TEMPS CRASH TO -12 TO -20 DEGREES C. THE THREAT FOR PRECIP WILL END FOR MOST AREAS...BUT CANNOT RULE OUT A FEW LIGHT SNOW SHOWERS OR FLURRIES FOR FAR WESTERN/NORTHERN AREAS. AS THE UPPER LEVEL TROUGH STARTS TO MOVE AWAY...MAINLY DRY WEATHER IS EXPECTED FOR FRI INTO FRI NIGHT...WITH CLEARING SKIES. TEMPS ALOFT WILL REMAIN CHILLY...SO TEMPS WILL CONTINUE TO BE COLD ACROSS THE REGION. HIGHS ON FRIDAY WILL ONLY BE 20S TO LOW 30S /TEENS OVER THE ADIRONDACKS/ AND LOWS ON FRI NIGHT WILL BE IN THE SINGLE DIGITS AND TEENS. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE LONG TERM PERIOD IS EXPECTED TO START DRY AND COOL AND QUICKLY TRANSITION TO MILDER AND WET CONDITIONS HEADING INTO EARLY NEXT WEEK. FOR SATURDAY A LARGE RIDGE OF HIGH PRESSURE IS EXPECTED TO STRETCH ALL THE WAY FROM THE GULF COAST STATES THROUGH THE NORTHEAST US AND INTO EASTERN CANADA. HIGHS ON SATURDAY WILL BE IN THE UPPER 20S TO UPPER 30S WITH LOWS SATURDAY NIGHT IN THE 20S. ON SUNDAY A BACKDOOR COLD FRONT IS EXPECTED TO SLIP SOUTH FROM CANADA AND STALL ACROSS THE REGION AS A WAVE OF LOW PRESSURE RACES EAST ALONG THE STALLED FRONT ON MONDAY. THERE WILL BE AN INCREASING CHANCE OF PRECIPITATION FROM SUNDAY NIGHT INTO MONDAY AS THE LOW PRESSURE SYSTEM MOVES INTO THE EASTERN GREAT LAKES. HIGHS ON SUNDAY ARE EXPECTED TO BE IN THE UPPER 30S TO AROUND 50 WITH LOWS SUNDAY NIGHT IN THE 30S AND HIGHS ON MONDAY IN THE MID 30S TO LOWER 50S. FOR MONDAY NIGHT AND TUESDAY HIGH PRESSURE WILL BE MOVING IN BEHIND THE FRONTAL BOUNDARY WITH MORE SEASONABLE TEMPERATURES. LOWS MONDAY NIGHT WILL BE IN THE MID TEENS TO UPPER 20S WITH HIGHS ON TUESDAY IN THE UPPER 20S TO MID 40S. FOR TUESDAY NIGHT AND WEDNESDAY YET ANOTHER FRONTAL BOUNDARY WILL APPROACH THE EASTERN GREAT LAKES AND BECOME NEARLY STATIONARY ALLOWING FOR MORE UNSETTLED CONDITIONS. LOWS ON TUESDAY NIGHT ARE EXPECTED TO BE IN THE MID TEENS TO UPPER 20S WITH HIGHS ON WEDNESDAY IN THE UPPER 20S TO MID 40S. && .AVIATION /21Z WEDNESDAY THROUGH MONDAY/... RAIN IS DEVELOPING OVER OUR AREA THIS AFTERNOON AND COVERAGE WILL INCREASE SO THAT ALL TAF SITES WILL SEE STEADIER RAIN DEVELOP. CEILINGS AND VISIBILITIES THROUGH THE TAF PERIOD ENDING 18Z THURSDAY WILL HOVER BETWEEN LOW MVFR AND IFR...WITH SOME PERIODS OF LIFR. VISIBILITIES WILL HOVER BETWEEN MVFR AND IFR THROUGH THE PERIOD AS WELL. RAIN WILL TEND TO END IN ALL AREAS BY 14Z-15Z...BUT SOME PATCHES OF RAIN MAY STILL BE AROUND TO REQUIRE VCSH TOMORROW MORNING. CEILINGS SHOULD IMPROVE INTO MVFR TOMORROW MORNING AS WELL. STRONG WINDS ABOVE THE SURFACE THIS AFTERNOON AND EVENING WILL REQUIRE A MENTION OF WIND SHEAR. ISOLATED THUNDER IS POSSIBLE TONIGHT...BUT NOT ENOUGH OF A CHANCE TO INCLUDE AT THIS TIME...BUT WILL WATCH LATER TRENDS FOR LATER TAF ISSUANCES THROUGH TONIGHT. LIGHT NORTH TO NORTHEAST WINDS THIS AFTERNOON WILL TREND TO SOUTHEAST AND SOUTH THROUGH TONIGHT. THEN BETWEEN 12Z-15Z TOMORROW...WINDS WILL SHIFT TO SOUTHWEST AT LESS THAN 10 KT. OUTLOOK... THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA...SHSN. FRIDAY: LOW OPERATIONAL IMPACT. BREEZY NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: SLIGHT CHANCE OF SHSN. SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. && .HYDROLOGY... WITH A STORM SYSTEM MOVING ACROSS THE REGION...RAIN WILL CONTINUE THROUGH THIS EVENING AND INTO THE OVERNIGHT HOURS. THE RAINFALL MAY BE LOCALLY MODERATE TO HEAVY AT TIMES...ESPECIALLY LATE THIS EVENING AHEAD OF THE STORM/S OCCLUDED FRONT. WITH THE RAINFALL OCCURRING WITHIN A SHORT PERIOD OF TIME...THERE MAY BE PONDING OF WATER ON AREA ROADWAYS...AS WELL AS IN LOW LYING AND POOR DRAINAGE AREAS...AND IN FIELDS AND YARDS IN PLACES WHERE THE GROUND REMAINS FROZEN. TOTAL QPF AMOUNTS LOOK TO BE ONE TO TWO INCHES...WITH THE HEAVIEST AMOUNTS ACROSS THE HIGHER ELEVATIONS. WITH A LARGE AMOUNT OF RUNOFF EXPECTED...THERE WILL BE LARGE RISES ON RIVERS AND STREAMS. A FEW RIVER POINTS LOOK TO EXCEED ACTION STAGE...AND COULD EVEN APPROACH FLOOD STAGE /SUCH AS IN PARTS OF THE HOOSIC AND UPPER MOHAWK BASINS/. RIVERS LOOK TO CREST ON THURSDAY MORNING...AND SHOULD QUICKLY START TO RECEDE...WITH ONLY LIGHTER RAIN SHOWERS EXPECTED ON THURSDAY. RIVERS SHOULD CONTINUE TO RECEDE FOR FRIDAY INTO THE WEEKEND...WITH MAINLY DRY WEATHER EXPECTED. JUST SOME PASSING SNOW SHOWERS AND FLURRIES LOOK TO OCCUR ON FRIDAY INTO FRI NIGHT FOR WESTERN AREAS...SOME LIGHT RAIN OR SNOW SHOWERS FOR SAT NIGHT INTO SUNDAY FOR NORTHERN AREAS. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...WIND ADVISORY FROM 9 PM THIS EVENING TO 4 AM EST THURSDAY FOR CTZ001-013. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS NEAR TERM...FRUGIS SHORT TERM...FRUGIS LONG TERM...11 AVIATION...NAS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
1244 PM EST WED FEB 24 2016 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL PASS WEST OF THE REGION THIS EVENING INTO TONIGHT...ALLOWING FOR PERIODS OF RAIN AND ISOLATED THUNDERSTORMS. TEMPERATURES WILL CONTINUE TO RISE TONIGHT...REACHING MILD LEVELS FOR TOMORROW...WITH SHOWERS ENDING. COOLER TEMPERATURES AND A FEW PASSING SNOW SHOWERS AND FLURRIES WILL RETURN ON FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1244 PM EST...TEMPERATURES CONTINUE TO ONLY VERY SLOWLY RISE ACROSS THE REGION...WITH MOST LOCATIONS STILL IN THE MID TO UPPER 30S. SOME LOCATIONS IN THE SOUTHEASTERN ADIRONDACKS AND SOUTHEASTERN VT REMAIN JUST BELOW FREEZING...SO WILL CONTINUE THE WINTER WEATHER ADVISORY IN THOSE AREAS THROUGH 3 PM DUE TO A LITTLE LINGERING FREEZING RAIN/FREEZING DRIZZLE...BUT ADDITIONAL ICE ACCRETION WILL LIKELY JUST BE A TRACE. ALL AREAS SHOULD BE ABOVE FREEZING BY THE MID AFTN HOURS...ENDING THE THREAT FOR FREEZING RAIN. BASED ON CURRENT KENX RADAR AND THE 3KM HRRR GUIDANCE...STEADY RAINFALL IS RETURNING TO THE REGION FOR THE AFTERNOON HOURS. ALTHOUGH RAINFALL WILL GENERALLY BE LIGHT...A FEW POCKETS OF MODERATE RAINFALL WILL BE POSSIBLE FROM TIME TO TIME. THERE COULD BE A RUMBLE OF THUNDER BY THIS EVENING...BUT THE BEST CHANCE OF THUNDER APPEARS TO BE THE LATE EVENING INTO TONIGHT ALONG THE STORM/S OCCLUDED BOUNDARY. TEMPS WILL CONTINUE TO HOLD STEADY OR ONLY VERY SLOWLY RISE. DAILY HIGH TEMPS WILL OCCUR JUST PRIOR TO MIDNIGHT...WITH TEMPS WARMING INTO THE 40S. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... A SOAKING RAIN WILL OVERSPREAD THE REGION THIS EVENING WITH RAINFALL RATES POTENTIALLY REACHING A QUARTER INCH PER HOUR OR MORE AT TIMES. IT LOOKS AS IF THE SHOWALTER INDEX COULD STILL DIP AT OR BELOW 0C ACROSS OUR ENTIRE REGION TONIGHT IMPLYING AN UNSTABLE ELEVATED ATMOSPHERE. THEREFORE WE WILL CONTINUE WITH SLIGHT CHANCES OF THUNDER. SPC HAS MUCH OF THE AREA IN A MARGINAL RISK FOR SEVERE T-STORMS...WITH LOCALLY GUSTY WINDS POSSIBLE WITHIN ANY THUNDERSTORM. A STRONG LOW LEVEL JET WILL BE WORKING ACROSS THE REGION ESPECIALLY DURING THE EVENING. THIS JET WILL SEND PWAT VALUES OVER AN INCH INTO OUR REGION...3-4 STANDARD DEVIATIONS ABOVE NORMAL FOR THE TIME OF YEAR. THE WIND AT H850 OFF THE GEFS LOOKS TO BE UP TO 60KTS...ALSO 3-4 STANDARD DEVIATIONS HIGHER THAN NORMAL REGARDING THE V (SOUTHERLY COMPONENT). H850 TEMPS WILL LIKELY REACH 10C OR BETTER. NOW...IF THUNDERSTORMS WERE ABLE TO DEVELOP...EVEN IF LOW TOPPED... THEY COULD EASILY TAP INTO THE WIND FIELD AND PRODUCE VERY STRONG GUSTS. EVEN WITHOUT THUNDERSTORMS SOME STRONG SYNOPTIC GUSTY WINDS ARE POSSIBLE... MAINLY OVER THE TACONICS AND SOUTHERN GREENS. WE DID NOT HOIST ANY WIND ADVISORIES JUST YET. WE WILL LET THE DAY CREW MAKE THE FINAL CALL ON ANY WIND HEADLINES. ONE MITIGATING FACTOR WILL BE A SATURATED COLUMN WHICH MAKE IT HARDER FOR A FULL MOMENTUM TRANSFER OF WIND TO THE SURFACE. MOST PLACES WILL AVERAGE 10-20 MPH FROM THE SOUTH OR SOUTHEAST... WITH GUSTS TO 30 MPH...POTENTIALLY HIGHER IN THUNDERSTORMS AND ACROSS THE ELEVATED TERRAIN MAINLY TO THE EAST OF THE HUDSON VALLEY. RAINFALL AMOUNTS LOOK TO BE 1-2 INCHES. HYDROLOGICAL ISSUES LOOK MINOR BUT ALL THE ISSUES ARE ADDRESSED IN OUR HYDRO SECTION. TEMPERATURES TONIGHT SHOULD RISE INSTEAD OF FALL...THROUGH THE 40S ACROSS MOST OF OUR REGION. DEWPOINTS WILL ALSO RISE WELL ABOVE FREEZING. THE COMBINATION OF RAIN...ELEVATED DEWPOINTS AND RAIN WILL LIKELY LEAD TO SNOWMELT IN THE ADIRONDACKS. BY THURSDAY...THE STRONGEST FORCING WILL SHIFT EAST AND A MID LEVEL DRY SLOT SHOULD TAPER THE RAIN TO SCATTERED SHOWERS...EVEN AHEAD OF A COLD FRONT. THE SOUTHERLY WIND WILL BECOME SOUTHWESTERLY THEN WESTERLY AS THE DAY WEARS ON. WHILE THE LOW LEVEL JET MOVES ON BY...WITH DRYING ALOFT THE WIND WOULD HAVE A BETTER CHANCE OF MIXING TO THE SURFACE. LOOK FOR THE WIND TO AVERAGE 10-15 MPH...BUT COULD OCCASIONALLY GUST OVER 30 MPH...ESPECIALLY WHEN THE COLD FRONT MOVES THROUGH...DURING THE AFTERNOON. HIGH TEMPERATURES SHOULD BRIEFLY SPIKE INTO THE LOWER TO MID 50S... AND EVEN CLOSE TO 50 ACROSS MOST OF THE HIGHER TERRAIN. IF WE WERE TO BREAK INTO MORE SUNSHINE (LIKE LAST SATURDAY) THESE NUMBERS COULD GO A BIT HIGHER AS THEY DID LAST SATURDAY. ADDITIONAL RAINFALL ON THURSDAY LOOKS MUCH LIGHTER THAN WEDNESDAY NIGHT... GENERALLY A QUARTER INCH OR LESS. THURSDAY NIGHT...IT WILL TURN COLDER BEHIND THE COLD FRONT AS H850 TEMPS FALL QUICKLY FROM +5C TO +9C LOWER THAN -10C BY FRIDAY. A GUSTY NORTHWEST WIND WILL GREET US FRIDAY MORNING AS TEMPERATURES TUMBLE TO THE 20S /TEENS NORTH/. THE COLUMN LOOKS MOIST ENOUGH FOR SOME UPSLOPE SNOW (ENHANCED BY LAKE ONTARIO MOISTURE) MAINLY OVER THE ADIRONDACKS...BUT SOME OVER THE CATSKILLS AND TERRAIN TO THE EAST OF ALBANY POSSIBLE AS WELL. THERE IS A POTENTIAL FOR LOCALIZED ACCUMULATIONS...ESPECIALLY OVER THE ADIRONDACKS PERHAPS APPROACHING ADVISORY LEVELS. WE WILL ADDRESS THAT POSSIBILITY TOMORROW NIGHT. VALLEY AREAS COULD SEE A DUSTING FROM SNOW SHOWERS LATE THURSDAY NIGHT INTO EARLY FRIDAY. OTHERWISE FRIDAY SHOULD BE A PARTLY SUNNY BLUSTERY DAY. HIGH TEMPERATURES WILL BE 30-35 IN MOST VALLEYS... 20S HIGHER TERRAIN. THE WIND 10-20 MPH...GUSTING TO 30 MPH... WILL MAKE IT FEEL ABOUT 10-15 DEGREES COLDER BUT NOWHERE NEAR DANGEROUS WIND CHILL LEVELS. IT WILL BE MOSTLY CLEAR AND COLD FRIDAY NIGHT WITH DIMINISHING WIND (BUT NOT COMPLETELY). LOWS WILL BE IN THE TEENS ALBANY SOUTHWARD...SINGLE NUMBERS TO THE NORTH. SATURDAY WILL BE DRY (OUTSIDE SOME SNOW SHOWERS ACROSS THE ADIRONDACKS) WITH PARTIAL SUNSHINE AND TEMPERATURES MODERATING BACK TO NEAR SEASONABLE LEVELS...MID TO UPPER 30S VALLEYS...CLOSER TO 30 HIGHER TERRAIN. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... THE PERIOD STARTS OUT SATURDAY NIGHT INTO SUNDAY MORNING WITH A POTENTIAL BACK DOOR COLD FRONT APPROACHING NORTHERN PARTS OF THE AREA. VARIOUS SOURCES OF GUIDANCE DIFFER WITH REGARDS TO HOW FAR SOUTH THIS FRONT WILL GET. THE GFS SHOWS THE BOUNDARY REMAINING WELL NORTH IN CANADA...WHILE THE ECMWF AND CMC HAVE THE FRONT PUSHING SOUTHWARD THROUGH AT LEAST THE NORTHERN HALF OF OUR AREA. THE POSITION OF THE FRONT WILL HAVE LARGE IMPLICATIONS FOR HIGH TEMPERATURES SUNDAY. WILL SPLIT THE DIFFERENCE FOR NOW AND MENTION HIGHS MAINLY IN THE 40S...WITH COOLER 30S IN THE ADIRONDACKS AND SOUTHERN GREENS. DUE THE THREAT OF THE FRONT NEARBY...WILL ALSO MENTION SLIGHT CHANCE TO LOW CHANCE POPS NORTH OF I-90. SUNDAY NIGHT INTO EARLY MONDAY...A DEEPENING CYCLONE IS FORECAST TO APPROACH FROM THE MIDWEST/GREAT LAKES REGION. DEPENDING ON HOW FAR SOUTH THE AFOREMENTIONED COLD FRONT PROGRESSES...THERE COULD BE A PERIOD OF MIXED PRECIP ASSOCIATED WITH THE FRONT LIFTING BACK NORTHWARD AS A WARM FRONT. AS THE CYCLONE CENTER TRACKS NORTHEAST ALONG THE ST LAWRENCE VALLEY...A BRIEF PERIOD OF WARMING IS POSSIBLE IN A MINI-WARM SECTOR AHEAD OF THE SYSTEM/S COLD FRONT. THIS COULD SENT TEMPERATURES BACK INTO THE 40S FOR MUCH OF THE AREA...EXCEPT COOLER 30S IN THE ADIRONDACKS WHERE THE COLD FRONT WILL BE MOVING THROUGH QUICKER. SOME RAIN SHOWERS WILL BE POSSIBLE ALONG THE COLD FRONT MONDAY...WITH SNOW SHOWERS ACROSS THE WESTERN ADIRONDACKS. IT WILL TURN COLDER ONCE AGAIN MONDAY NIGHT BEHIND THE COLD FRONT WITH A LEFTOVER SNOW SHOWER POSSIBLE IN SOME SPOTS. MODELS CONTINUE TO SHOW DIFFERING SOLUTIONS FOR THE TUESDAY TO WEDNESDAY TIME FRAME...AS THE GFS INDICATES A CLIPPER-TYPE SYSTEM QUICKLY PASSING THROUGH TUESDAY MORNING...WHILE THE ECMWF HAS A WAVE OF LOW PRESSURE DEVELOPING ALONG A STALLED FRONTAL BOUNDARY TO OUR SOUTH TUESDAY NIGHT INTO WEDNESDAY. EITHER WAY IT LOOKS LIKE THERE WILL BE POTENTIAL FOR SOME ACCUMULATING SNOW AT SOME POINT NEXT WEEK...BUT THE DETAILS ARE STILL QUITE UNCERTAIN...AS FORECAST STORM TRACKS WILL LIKELY CHANGE BETWEEN NOW AND THEN. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... RAIN IS DEVELOPING OVER OUR AREA THIS AFTERNOON AND COVERAGE WILL INCREASE SO THAT ALL TAF SITES WILL SEE STEADIER RAIN DEVELOP. CEILINGS AND VISIBILITIES THROUGH THE TAF PERIOD ENDING 18Z THURSDAY WILL HOVER BETWEEN LOW MVFR AND IFR...WITH SOME PERIODS OF LIFR. VISIBILITIES WILL HOVER BETWEEN MVFR AND IFR THROUGH THE PERIOD AS WELL. RAIN WILL TEND TO END IN ALL AREAS BY 14Z-15Z...BUT SOME PATCHES OF RAIN MAY STILL BE AROUND TO REQUIRE VCSH TOMORROW MORNING. CEILINGS SHOULD IMPROVE INTO MVFR TOMORROW MORNING AS WELL. STRONG WINDS ABOVE THE SURFACE THIS AFTERNOON AND EVENING WILL REQUIRE A MENTION OF WIND SHEAR. ISOLATED THUNDER IS POSSIBLE TONIGHT...BUT NOT ENOUGH OF A CHANCE TO INCLUDE AT THIS TIME...BUT WILL WATCH LATER TRENDS FOR LATER TAF ISSUANCES THROUGH TONIGHT. LIGHT NORTH TO NORTHEAST WINDS THIS AFTERNOON WILL TREND TO SOUTHEAST AND SOUTH THROUGH TONIGHT. THEN BETWEEN 12Z-15Z TOMORROW...WINDS WILL SHIFT TO SOUTHWEST AT LESS THAN 10 KT. OUTLOOK... THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA...SHSN. FRIDAY: LOW OPERATIONAL IMPACT. BREEZY NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN. MONDAY: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA. && .HYDROLOGY... A HEAVY PERIOD OF RAIN IS EXPECTED FOR LATE TODAY INTO THURSDAY MORNING. RAINFALL AMTS OF 1 TO 2 INCHES ARE STILL EXPECTED...PERHAPS A TAD LOWER THAN EARLIER ADVERTISED. AS A RESULT AT THIS TIME...ONLY THE SREFS OFF THE METEOROLOGICAL MODEL ENSEMBLE RIVER FORECASTS (MMEFS) INDICATE ANY RIVER POINT GOING ABOVE FLOODING (WILLIAMSTOWN AND HOPE) WHILE THE GEFS AND NAEFS DO INDICATE ANY FLOODING BUT PLENTY OF POINTS REACHING ACTION STAGES. AT THE VERY LEAST EXPECT SIGNIFICANT WITHIN BANK RISES ON MANY RIVER AND STREAMS. A LOWER THAN AVERAGE SNOW PACK WILL CERTAINLY HELP MITIGATE ANY FLOOD POTENTIAL. NO FLOOD WATCHES HAVE BEEN ISSUED AT THIS TIME. THAT SAID...THE RAINFALL WILL ALSO LIKELY CAUSE SOME PONDING ON ROADWAYS AND PERHAPS SOME MINOR URBAN FLOODING. THE RAIN WILL TAPER TO SCATTERED RAIN SHOWERS ON THURSDAY. RUNOFF WILL CONTINUE THURSDAY AS TEMPERATURES ARE ELEVATED. COLDER AIR MOVING BACK THURSDAY NIGHT INTO FRIDAY WILL SLOW THE RUNOFF. MAINLY DRY WEATHER THIS WEEKEND WITH THE NEXT CHANCE OF SHOWERS MONDAY. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR NYZ033-041>043-083. MA...NONE. VT...WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR VTZ014-015. && $$ SYNOPSIS...FRUGIS NEAR TERM...FRUGIS SHORT TERM...HWJIV LONG TERM...JPV AVIATION...NAS HYDROLOGY...HWJIV/KL
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
357 PM EST WED FEB 24 2016 .DISCUSSION... ...POTENTIAL FOR STRONG TO SEVERE STORMS WIND DOWN NORTH TO SOUTH THROUGH MID EVENING... ...TURNING DRY AND MUCH COOLER THURSDAY...REMAINING WINDY... CURRENT-THIS EVENING...A LINE OF SHOWERS AND STORMS WILL MOVE EAST ACROSS OSCEOLA...ORANGE...SEMINOLE AND VOLUSIA COUNTIES AND EXIT INTO THE ATLANTIC THROUGH THE REST OF THE AFTERNOON AND EARLY EVENING. A LARGE SWATH OF SHOWERS AND STORMS WERE MOVING ACROSS EAST CENTRAL FLORIDA FROM SOUTH OSCEOLA COUNTY TO OKEECHOBEE COUNTY EAST TO THE SOUTHERN BREVARD TO MARTIN COUNTY AND INTO THE COASTAL WATERS THROUGH MID EVENING. BOTH THE HRRR AND LOCAL WRF MODELS WERE INDICATING STORMS AND SHOWERS CLEARING SOUTHERN COUNTIES AROUND 10 PM THIS EVENING. STRONG SOUTH TO SOUTHWEST WINDS AHEAD OF THE STORMS SHIFT TO THE WEST OVERNIGHT NORTH TO SOUTH AS THE LINE OF STORMS CLEARS OUR SOUTHERN COUNTIES. WATER VAPOR SATELLITE LOOP SHOWING A DRIER AIR MASS MOVING TOWARD CENTRAL FLORIDA BEHIND THE FRONT. SLIGHT CHANCE/20 POP OF PRIMARILY SHOWERS SEBASTIAN/INDIAN RIVER COUNTY SOUTH DURING THE EVENING WIND DOWN/EXIT MARTIN COUNTY AROUND MIDNIGHT. WINDS REMAIN OUT OF THE WEST AT 10 TO 15 MPH MOST OF THE OVERNIGHT. LOWS UPPER 40S NORTH TO LOW/MID 50S SOUTHERN AREAS. THU...THE FRONT WAS LOCATED WELL SOUTH OF CENTRAL FLORIDA...BAHAMA ISLANDS AND WESTERN CUBA. HIGH PRESSURE AT THE SURFACE BUILDS FROM THE HIGH PLAINS DOWN TO TEXAS THEN EAST ACROSS THE GULF COAST AND NORTHERN GULF OF MEXICO. DEEPENING UPPER LEVEL LOW OVER THE EASTERN GREAT LAKES LIFTS NORTHEAST. BROAD TROUGHING ASSOCIATED WITH THE LOW REACHES ALL THE WAY INTO THE SOUTHWESTERN GULF OF MEXICO PUSHES THE SURFACE OVER FLORIDA. WEST TO NORTHWEST WINDS 10 TO 15 MPH DIMINISH TO 5 TO 10 MPH AT NIGHT. HIGHS MID 60S...LOWS LOW AND MID 40S EXCEPT UPPER 30S EASTERN OSCEOLA...OKEECHOBEE AND WEST OF INTERSTATE 95 INDIAN RIVER AND SAINT LUCIE COUNTIES. FRI-SUN...HIGH PRESSURE OVER THE NORTHWEST GULF/TX/LA SHIFTS EAST TO NORTH/CENTRAL FLORIDA SUN. NORTHWEST WINDS FRI SHIFT TO NORTH 10 MPH SAT THEN NORTHEAST TO EAST 5 TO 10 MPH SUN. RAIN CHANCES AROUND 10 PERCENT OR LESS. HIGHS MID/UPPER 60S FRI AND SAT THEN LOW 70S SUN. LOWS MID/UPPER 30S SAT MORNING...LOW 40S TO UPPER 40S NORTH TO SOUTH SUN MORNING AND UPPER 40S/LOW 50S MON MORNING. MON-WED...HIGH PRESSURE OVER FLORIDA MON SLOW SHIFTS NORTH THROUGH WED. GENERALLY LIGHT WINDS. HIGHS IN THE LOW/MID 70S. LOWS MID/UPPER 50S. && .AVIATION... TEMPO MVFR/IFR IN/VC TSTMS/SHWRS MCO-TIX NORTH AND MLB LAKE KISSIMMEE SOUTH THROUGH 02Z. TEMPO MVFR CEILINGS TIL 16Z. STORMS/SHOWERS END NORTH TO SOUTH DURING THE EVENING. && .MARINE... THIS EVENING-TONIGHT-FRI...STRONG GUSTY SOUTHWEST TO WEST WINDS AHEAD OF AND JUST BEHIND THE FRONT THAT CLEARS SOUTHERN WATERS AFTER MIDNIGHT. GALE WARNING OFFSHORE ENDS THU MORNING THEN SMALL CRAFT ADVISORY THU LATE OVERNIGHT THU/EARLY FRI MORNING. SMALL CRAFT EXERCISE CAUTION EARLY FRI MORNING TO OVERNIGHT FRI/SAT MORNING. SAT-MON...MODERATE NORTH WINDS BECOME LIGHT EAST SUN AND MON. AREA. SEAS CONTINUE TO SUBSIDE TO 2-4 FT FRI OVERNIGHT...REMAINING NEAR THESE VALUES THRU THE WEEKEND. && .FIRE WEATHER... PREVIOUS FIRE DISCUSSION THU-FRI...VERY DRY POST FRONTAL AIRMASS WILL ALLOW AFTN MIN RH VALUES TO FALL INTO THE U20S-30S AREAWIDE. GUSTY W/WNW 20 FT WINDS ON THU DECREASING INTO FRI. DISPERSION SHOULD BE VG- EX. SAT-SUN...CONTINUED DRY AIRMASS IN PLACE WITH MIN RH VALUES IN THE 30S AGAIN FOR SAT...THEN M-U30S WELL INTO THE INTERIOR ON SUN AND M- U40S ALONG THE COAST AS WINDS FINALLY VEER TO NE/E BRINGING A LITTLE MOISTURE BACK INTO THE AREA. WINDS WILL BE LIGHTER AS HIGH PRESSURE SETTLES INTO THE AREA WITH A WEAKER PRESSURE GRADIENT. && .PRELIMINARY POINT TEMPS/POPS... DAB 48 65 42 62 / 0 10 10 10 MCO 50 66 42 67 / 0 0 10 10 MLB 52 66 43 66 / 10 0 10 10 VRB 54 67 40 67 / 20 0 10 10 LEE 48 65 44 65 / 0 0 10 10 SFB 48 66 43 65 / 0 10 10 10 ORL 50 66 46 66 / 0 0 10 10 FPR 54 68 41 67 / 20 10 10 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR COASTAL VOLUSIA COUNTY-INDIAN RIVER-INLAND VOLUSIA COUNTY-MARTIN-NORTHERN BREVARD COUNTY-NORTHERN LAKE COUNTY-OKEECHOBEE-ORANGE- OSCEOLA-SEMINOLE-SOUTHERN BREVARD COUNTY-SOUTHERN LAKE COUNTY-ST. LUCIE. AM...SMALL CRAFT ADVISORY UNTIL 4 AM EST FRIDAY FOR FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 0-20 NM-SEBASTIAN INLET TO JUPITER INLET 0-20 NM-SEBASTIAN INLET TO JUPITER INLET 20- 60 NM-VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 0-20 NM. GALE WARNING UNTIL 10 AM EST THURSDAY FOR FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 20-60 NM-VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 20-60 NM. && $$ IMPACT WX...LASCODY/ULRICH FORECASTS...WIMMER
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
119 AM EST WED FEB 24 2016 .SYNOPSIS... WARM FRONT SOUTH OF THE FORECAST AREA HAS SLOWLY BEGUN LIFTING NORTHWARD WITH A STRONG COLD FRONT CURRENTLY CROSSING THE CENTRAL GULF STATES. THE COLD FRONT WILL MOVE THROUGH THE AREA THIS AFTERNOON FOLLOWED BY A DRIER AIR MASS. SEVERE THUNDERSTORMS MAY BE ASSOCIATED WITH THIS SYSTEM. STRONG AND GUSTY WINDS WILL BE ACROSS THE AREA THIS MORNING THROUGH THURSDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... WARM FRONT CURRENTLY LOCATED NEAR AN ATL-AGS-MYR LINE LATE THIS EVENING. THE MODELS SHOW THE WARM FRONT LIFTING NORTHWARD IN THE STRONG SOUTH FLOW AHEAD OF THE COLD FRONT LATE TONIGHT. THE NAM SURFACE- BASED LI PATTERN SUGGESTS THE WARM FRONT WILL EXTEND THROUGH THE NORTH PART OF THE FORECAST AREA BY 12Z. SHOWERS THROUGH TONIGHT WILL BE MAINLY ASSOCIATED WITH CONVERGENCE NEAR THE WARM FRONT AND ISENTROPIC LIFT. WATER VAPOR IMAGERY TRENDS INDICATE MUCH OF THE UPPER-LEVEL LIFT WILL HOLD OFF UNTIL LATE TONIGHT. THE SPC WRF AND HRRR DISPLAYED SCATTERED COVERAGE. SHEAR WILL BE ON THE INCREASE. THE MODELS HAVE BEEN CONSISTENT INDICATING H85 WINDS INCREASING TO NEAR 45 KNOTS BY 12Z. EXPECT WEAK INSTABILITY BECAUSE OF NOCTURNAL COOLING. THE NAM DISPLAYS SURFACE-BASED LI/S 0 TO -1 IN THE CENTRAL AND SOUTH SECTIONS OF THE FORECAST AREA LATE TONIGHT AND TOWARD SUNRISE. DESPITE THE WEAK INSTABILITY THE STRONG SHEAR MAY BE ENOUGH TO SUPPORT SEVERE THUNDERSTORMS INCLUDING TORNADOES MAINLY IN THE CSRA TOWARD SUNRISE WHEN GREATER UPPER-LEVEL LIFT WILL BE APPROACHING FROM THE SOUTHWEST. PATCHY FOG ALREADY DEVELOPING NORTH OF THE WARM FRONT THIS EVENING. EXPECT THE FOG TO PERSIST WELL INTO THE OVERNIGHT HOURS UNTIL THE WARM FRONT BEGINS TO LIFT NORTH. WILL NEED TO MONITOR IF DENSE FOG DEVELOPS IN THE NEXT FEW HOURS. EXPECT STEADY OR SLOWLY RISING TEMPERATURES OVERNIGHT. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 AM THURSDAY/... THE MAIN FORECAST CONCERN IS THE RISK OF SEVERE THUNDERSTORMS WEDNESDAY AND STRONG SYNOPTIC-SCALE WIND BEHIND THE COLD FRONT WEDNESDAY AFTERNOON CONTINUING THROUGH WEDNESDAY NIGHT. WEDNESDAY...THE SEVERE THREAT WILL LIKELY BE GREATEST ASSOCIATED WITH THE WARM FRONT LIFTING NORTHWARD THROUGH THE FORECAST AREA EARLY IN THE DAY AND STRONG COLD FRONT IN THE AFTERNOON. THE NAM SURFACE-BASED LI PATTERN SUGGESTS THE WARM FRONT WILL HAVE LIFTED NORTH OF THE ENTIRE REGION BY 18Z WEDNESDAY. THE MODELS HAVE BEEN CONSISTENT SHOWING STRONG SHEAR WITH AN H85 JET OF 50 TO 60 KNOTS. THE GUIDANCE CONSENSUS HAS THE CORE OF THIS JET THROUGH THE FORECAST AREA ABOUT MIDDAY. THERE WILL BE A THREAT OF DAMAGING WIND INCLUDING TORNADOES ALONG WITH HAIL. THE TORNADO THREAT MAY BE GREATEST EARLY IN THE DAY ASSOCIATED WITH THE ADDED SHEAR NEAR THE WARM FRONT. DIRECTIONAL SHEAR MAY BE LESS DURING THE AFTERNOON BUT A MID-LEVEL DRY SLOT OVERSPREADING THE AREA NEAR THE COLD FRONT MAY HELP ENHANCE DOWNDRAFTS. WE HAVE INCLUDED THE THREAT OF DAMAGING WIND IN THE FORECAST. THE NAM BUFKIT INDICATES A MEAN OF 36 KNOTS IN THE MIXED LAYER WEDNESDAY AFTERNOON WITH 50 KNOTS AT THE TOP OF THE LAYER. EXPECT WIND GUSTS AROUND 45 MPH AND THIS HAS PROMPTED US TO ISSUE A GENERAL WIND ADVISORY. THE MODELS HAVE TRENDED DOWNWARD WITH GENERAL RAINFALL WEDNESDAY. THE NAM INDICATED 0.25 TO 0.50 OF AN INCH. THE GFS AND ECMWF HAD LESS THAN 0.25 OF AN INCH. THE SREF MEAN WAS AROUND 0.40 OF INCH. THE THREAT OF FLOODING WAS TOO LOW FOR A FLOOD WATCH AT THIS TIME. DRYING SHOULD OCCUR BEHIND THE COLD FRONT FOR WEDNESDAY NIGHT. ALTHOUGH A MID-LEVEL SHORTWAVE TROUGH COULD POSSIBLY SUPPORT SHOWERS MAINLY IN THE NORTH PART. THE MODELS INDICATE A TIGHT PRESSURE GRADIENT ASSOCIATED WITH STRONG LOW PRESSURE NORTH OF THE AREA. WE MAINTAINED THE WIND ADVISORY. && .LONG TERM /THURSDAY THROUGH TUESDAY/... ON THURSDAY...STRONG UPPER AND SURFACE LOWS TO OUR NE WITH SURFACE HIGH PRESSURE CENTERED TO OUR WEST...WITH AN UPPER DISTURBANCE AND DRY REINFORCING SURFACE TROUGH MOVING THROUGH. CONTINUED TIGHT SURFACE PRESSURE GRADIENT OVER THE REGION WILL RESULT IN CONTINUED WINDY CONDITIONS. THE WIND ADVISORY WILL CONTINUE THROUGH THURSDAY. THROUGH THE PERIOD...UPPER TROUGHINESS WILL REMAIN OVER THE E CONUS...WITH A SERIES OF EMBEDDED UPPER DISTURBANCES AND DRY SURFACE BOUNDARIES MOVING THROUGH IN A DRY NW FLOW ALOFT DRIVING COOLER AND DRIER AIR INTO THE FORECAST AREA. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... HIGH CONFIDENCE IN RESTRICTIONS AND LLWS THROUGH 18Z...THEN IMPROVING CONDITIONS. ISOLATED SHOWERS HAVE BEGUN DEVELOPING ACROSS THE AREA...WITH A LARGE AREA OF SHOWERS AND THUNDERSTORMS CURRENTLY CROSSING CENTRAL GA. EXPECT SHOWERS AND THUNDERSTORMS TO MOVE INTO AGS/DNL AROUND 08Z...THEN SPREAD INTO CAE/CUB/OGB BETWEEN 09 AND 10Z. LLWS IS ALSO A CONCERN AS WINDS A 2KFT ARE CURRENTLY 40 KNOTS. WINDS AT 5 KFT ARE EXPECTED TO BE BETWEEN 60 AND 70 KNOTS THROUGH THE DAY. CONCERN WITH THE THUNDERSTORMS WILL BE THE POTENTIAL FOR THE DAMAGING WIND GUSTS AS THE HIGHER WIND SPEED MIX TO THE SURFACE. WITH THE DIRECTIONAL SHEAR THERE IS POTENTIAL FOR AN ISOLATED TORNADO. SURFACE WINDS WILL RAPIDLY INCREASE AND VEER THROUGH THE MORNING HOURS...WITH SOUTHERLY AT 20 GUSTING 30KT AT SUNRISE...BECOMING SOUTHWESTERLY AT 25 GUSTING UP TO 35 BY 17Z. CONDITIONS WILL IMPROVE AFTER 17Z AS THE COLD FRONT MOVES EAST OF THE TAF SITES...HOWEVER WINDY CONDITIONS WILL CONTINUE THROUGH THE END OF THE PERIOD. EXTENDED AVIATION OUTLOOK...HIGH CONFIDENCE IN WINDY CONDITIONS CONTINUING INTO THURSDAY NIGHT. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THURSDAY FOR GAZ040-063>065-077. SC...WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THURSDAY FOR SCZ015-016-018-020>022-025>031-035>038-041. && $$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
634 PM EST THU FEB 25 2016 .SYNOPSIS... ISSUED AT 340 PM EST THU FEB 25 2016 A WEAK FRONT WILL MOVE ACROSS THE AREA TONIGHT AND WILL BRING SLIGHTLY COLDER TEMPERATURES. LIGHT LAKE EFFECT SNOW SHOWERS ARE ALSO EXPECTED TONIGHT BUT WILL DIMINISH EARLY FRIDAY. ANY ACCUMULATIONS WILL BE AROUND AN INCH OR LESS. HIGH PRESSURE WILL BUILD IN FOR FRIDAY AND SATURDAY PROVIDING QUIET WEATHER. A NICE WARM UP IS EXPECTED BUT THE RECENT SNOWPACK WILL TEMPER THE WARMTH INITIALLY. LOWS TONIGHT WILL BE IN THE 20S WITH SOME TEENS IN THE NORTH. HIGHS ON FRIDAY WILL BE IN THE LOWER 30S. THE OUTLOOK FOR THIS WEEKEND IS FOR HIGHS INTO THE 40S ON SATURDAY AND 50S FOR SUNDAY WITH A CHANCE OF RAIN SUNDAY. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 336 PM EST THU FEB 25 2016 A MUCH QUIETER SHORT TERM AS SYNOPTIC SNOW COMES TO AN END AND WINDS CONTINUE TO DIMINISH TONIGHT. MAIN FOCUS ON LIGHT LAKE EFFECT TONIGHT. DRIER AIR WAS WORKING SOUTH AND SYNOPTIC SNOW WILL BE DONE BEFORE 00Z. HIRES GUIDANCE SHOWING LAKE EFFECT BANDS SETTING UP AROUND 00Z BUT RADAR RETURNS INDICATE LIGHT SNOW SHOWERS ALREADY DEVELOPING. WEAK MID LEVEL SHORT WAVE AND ASSOCIATED SFC TROUGH WILL BRING A THERMAL TROUGH ACROSS THE LAKE AND INVERSION HEIGHTS BRIEFLY RISE TO AROUND 5-6KFT FOR JUST A FEW HOURS THIS EVENING BEFORE COMING BACK DOWN TO AROUND 4KFT REST OF NIGHT. TRAJECTORIES AND DGZ FAVORABLE BUT INSTABILITY VERY LIMITED WITH DELTA T/S 13-14C. HRRR AND RUC13 HAVE BEEN RATHER CONSISTENT ALL DAY SHOWING LIGHT BANDS DEVELOPING WITH A FEW HUNDREDTHS QPF. GIVEN RADAR SIGNALS ALREADY HAVE SIDED TOWARD THE HIRES GUIDANCE. ARW-WRF HAS DONE WELL THIS SEASON WITH LES BANDS AND BLENDED IT WITH LATEST RUC FOR FORECAST. BANDS SHOWN BY MOST MODELS TO PENETRATE RATHER FAR INLAND AND DOWN TO CENTRAL IN AND INTO OHIO WITH HELP FROM SHORT WAVE. THEREFORE CARRIED LOW POPS ALL THE WAY TO SOUTHERN BORDER. STILL THINK ACCUMS WILL BE AN INCH OR LESS GIVEN THE LIMITING FACTORS BUT ISOLATED 2 POSSIBLE IN FAR NORTH IF A STRONGER BAND DEVELOPS IN BRIEF BUT PRIME WINDOW. OTHERWISE NOTHING SIGNIFICANT TO NOTE IN SHORT TERM. POSSIBILITY OF NORTHEAST BEING CLEAR AFTER SHORT WAVE WITH WINDS DROPPING OFF TO 5 KNOTS OR SO LATE TONIGHT. THIS COULD ALLOW TEMPS TO DROP RAPIDLY TOWARD SUNRISE WITH FRESH SNOWPACK. CONTINUED TO SIDE TOWARD OR BELOW LOWER END OF MOS. ALSO KEPT HIGHS IN LOWER END FRIDAY AND FRIDAY NIGHT. && .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 336 PM EST THU FEB 25 2016 WARM UP WILL BE UNDERWAY AT THE START OF THE PERIOD...INITIALLY INFLUENCED BY RIPENING AND SLOWLY MELTING SNOWPACK. AM HESITANT TO INCREASE TEMPS TOO MUCH ESPECIALLY WHERE 8 INCHES OR MORE OF SNOW CURRENTLY RESIDES AND AT LEAST 2 THAW/FREEZE CYCLES TO OCCUR BEFORE WE STAY ABOVE FREEZING STARTING SATURDAY. HAVE ALLOWED HIGHS TO REACH AT LEAST 40 ACROSS THE AREA WITH WARMEST READINGS IN FAR SOUTH. WENT SLIGHTLY WARMER ON SUNDAY AS WELL AS PACIFIC SYSTEM MOVES INTO THE GREAT LAKES AND BEGINS TO PULL UP AT LEAST SOME GULF MOISTURE LATE SUNDAY INTO SUNDAY NIGHT. NOT SURE IF DEEPER MSTR WILL PHASES IN TIME WITH THE SYSTEM TO WARRANT EXPANDED LIKELY OR EVEN CAT POPS SO HAVE LEFT PREVIOUS FORECAST GENERALLY UNTOUCHED. BEST CHANCE WILL BE ACROSS THE NORTH AND EAST CLOSER TO THE SFC LOW. WITH REGARDS TO PRECIP TYPE...ALL LIQUID PRECIP WILL BE SEEN INTO SUNDAY EVENING BEFORE A TRANSITION TO SNOW BY SUNDAY NIGHT. INFLUENCE OF SLIGHTLY COOLER AIR WILL BE SHORT AS MAIN FOCUS YET ANOTHER WAVE IN A VERY ACTIVE FLOW ENTERS THE NW STATES AND THEN BEGINS TO CARVE OUT A DEEPER TROUGH AS IT ENTERS THE PLAINS AND EVENTUALLY GREAT LAKES. ECMWF/GFS VARY ON HANDLING WITH ECMWF BRINGING A OPEN BUT EVENTUALLY NEGATIVELY TILTED WAVE MOVING THROUGH VS GFS CUTTING OFF A DEEP UPPER LOW TO TRACK ACROSS MI. LOTS OF SPECULATION WITH REGARDS TO IMPACTS ON THE AREA...BUT GIVEN NOTED DIFFERENCES...PERIOD OF INTEREST PAST DAY 5 AND CRITICAL THERMAL PROFILES/SFC LOW TRACK ALL IN QUESTIONS...HAVE TO CONSIDER JUST ABOUT ANY FORM OF PRECIP AND WEATHER POSSIBLE AT THIS JUNCTURE FROM FROZEN/FREEZING ALL THE WAY TO RAIN AND THUNDERSTORMS. CONFIDENCE NOT LIKELY TO INCREASE MUCH UNTIL LATE IN THE WEEKEND AS WAVE OF INTEREST BECOMES SAMPLED IN THE UPPER AIR NETWORK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 626 PM EST THU FEB 25 2016 STRATO CU DECK EXTENDS UPSTREAM TO THE MS VALLEY AND WILL LIKELY CONT TO IMPACT THE TERMINALS THROUGH THE PERIOD. SFC RIDGE OVER THE PLAINS EXPECTED TO MOVE RAPIDLY EAST ACROSS INDIANA FRIDAY AFTN WITH CLEARING LIKELY TAKING PLACE BEHIND THIS FEATURE BEYOND THE END OF THE TAF PERIOD. CIGS SHOULD GENERALLY BE HIGH MVFR OR LOW VFR TONIGHT AND FRIDAY. SOME LAKE EFFECT -SHSN EXPECTED OVERNIGHT BUT AVIATION IMPACT SHOULD BE MINOR AS MEAGER LAKE INDUCED CAPE FCST. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR LMZ043-046. && $$ SYNOPSIS...AGD SHORT TERM...LASHLEY LONG TERM...FISHER AVIATION...JT VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
551 PM EST WED FEB 24 2016 .SYNOPSIS... ISSUED AT 410 PM EST WED FEB 24 2016 SNOW IS EXPECTED TO CONTINUE TONIGHT INTO THURSDAY MORNING BEFORE DIMINISHING. STRONG NORTH TO NORTHWEST WINDS OF 20 TO 30 MPH WITH GUSTS TO 35 MPH WILL CREATE BLOWING AND DRIFTING SNOW. ROADS WILL BE SNOW COVERED SLICK AND HAZARDOUS. BLIZZARD CONDITIONS ACROSS NORTHWEST INDIANA AND NORTHEAST ILLINOIS MAY MAKE TRAVEL IMPOSSIBLE ON SOME ROADS. REFER TO THE LATEST WINTER WEATHER PRODUCTS FOR MORE INFORMATION. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 405 PM EST WED FEB 24 2016 WATER VAPOR SHOWS UPPER CIRCULATION OVER SOUTHERN INDIANA WITH DRY SLOT DRIVING INTO NORTHEAST INDIANA AND NORTHWEST OHIO THIS AFTERNOON. SURFACE LOW WAS MOVING THROUGH SOUTHWEST OHIO AND EXPECTED TO LIFT TOWARD NORTHEAST OHIO THIS EVENING. IMPRESSIVE COUPLED UPPER LEVEL JET PROVIDED FOCUS FOR STRONG ASCENT TODAY WHICH QUICKLY COOLED THE COLUMN AND LED TO RAPID SNOW DEVELOPMENT NORTHWEST HALF OF THE AREA. THIS CERTAINLY HAS BEEN AN INTERESTING EVENT TO WATCH UNFOLD. HIGH DGZ...STRONG WINDS AND SATURATED COLUMN BELOW DGZ LED TO AN INTERESTING PATTERN TODAY WITH PCPN TYPES AND ACCUMULATIONS. OBSERVATIONS AT KIWX SAW SNOWFLAKE SIZE AND PRECIPITATION INTENSITY CHANGE DRAMATICALLY IN JUST A MATTER OF MINUTES. BANDS OF STRONGER SNOW AND DEEPER LIFT PRODUCED LARGE SNOWFLAKES WHILE INTERMITTENT PERIODS BETWEEN HEAVIER BANDS SAW SNOWFLAKE SIZE DWINDLE TO VERY FINE FLAKES AND EVEN SNOW PELLETS AND SLEET AT TIMES WITH SOME MELTING AND REFREEZING. TO OUR SOUTHEAST...WARM LAYER CHANGED PCPN OVER TO RAIN BEFORE DRY SLOT ENDED PCPN ENTIRELY. WHILE MUCH OF NORTHWEST AREA HAS SEEN THE HEAVY SNOWFALL TODAY...REPORTS FROM KSBN AND METRO AREA HAVE BEEN ON THE LIGHT SIDE WITH JUST A COUPLE INCHES REPORTED THROUGH MID AFTERNOON. WITH SFC TEMPS ABOVE FREEZING AND URBAN SETTING THERE MAY HAVE BEEN FASTER COMPACTION AND MELTING PROCESSES WITH SNOW ON GROUND COMPARED TO MORE RURAL AREAS. REST OF EVENING WILL SEE DRY SLOT FILL IN AS EXPANDING AREA OF PRECIPITATION TO OUR SOUTH ROTATES NORTH. DEFORMATION ZONE TO EXPAND EAST ACROSS THE AREA AS LOW PULLS AWAY. COLDER AIR WILL EXPAND EAST AND SHOULD CHANGE PCPN TYPE TO ALL SNOW BY MID EVENING IN FAR EAST. RUC AND HRRR HAD A GOOD HANDLE ON PCPN TYPES TODAY AND USED THESE ALONG WITH NAM12 BLENDED FOR TIMING OF CHANGEOVER IN POWT PROCESS FOR FORECAST GRIDS. LIQUID SNOW RATIOS HAVE BEEN LOW AS EXPECTED WITH AROUND 10 TO 1 AVERAGE. SHOULD SEE THESE IMPROVE OVERNIGHT WITH SLIGHTLY COLDER AIR AND DGZ LOWERING. LAKE ENHANCED SNOW BAND STILL EXPECTED TO SWING OFF THE LAKE INTO NW AND NC INDIANA WITH STRONG CYCLONIC FLOW. THIS SHOULD LEAD TO ADDITIONAL MODERATE TO HEAVY BURST OF SNOW. OVERALL INHERITED ACCUMS LOOK GOOD WITH REPORTS RECEIVED ALREADY...TOTAL ACCUMS AROUND A FOOT STILL POSSIBLE NW INDIANA TO SW MICHIGAN BY THURSDAY AFTERNOON WHEN SNOW COMES TO AN END. HEAVY WET SNOW ALONG WITH WINDS JUST BELOW BLIZZARD CRITERIA HAS KEPT NW AREAS FROM SEEING TRUE BLIZZARD CONDITIONS. HOWEVER...REPORTS OF WHITEOUT CONDITIONS AT TIMES WITH NEAR BLIZZARD CONDITIONS WARRANT KEEPING THE BZW IN PLACE THROUGH THE EVENING. SOME STRONGER GUSTS STILL POSSIBLE THIS EVENING WITH GRADIENT AS WELL. WINTER STORM WARNING REMAINS INTACT AND EXPANDED ADVISORY EAST FOR TONIGHT AND THURSDAY FOR COMBINATION OF ADDITIONAL SNOWFALL AND STRONG WINDS CREATING BLOWING AND DRIFTING ISSUES. && .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 405 PM EST WED FEB 24 2016 FORECAST PERIOD TO BEGIN ON THE QUIET SIDE FRIDAY WITH DIMINISHING LAKE EFFECT SNOW SHOWERS AS SURFACE RIDGE AXIS SHIFT EASTWARD AND FLOW QUICKLY BACKS AROUND TO THE W/SW. DRY WEATHER WILL CONTINUE THROUGH SATURDAY WITH SEASONABLE TEMPS. OVERALL PATTERN NOT CHANGING MUCH IN THE EXTENDED PERIOD WITH PERSISTENT UPPER LOWS OVER THE HUDSON BAY AND ALEUTIANS AND UPPER RIDGE REMAINING OVER THE WESTERN US. FIRST IN A SERIES OF SHORT WAVES WILL BE ROTATING OUT OF ALEUTIAN LOW AND ENTERING WEST COAST FRIDAY NIGHT. THIS WILL UNDERCUT THE WESTERN RIDGE AND MOVE INTO THE CENTRAL PLAINS SUNDAY MORNING. DEEPENING SURFACE LOW ASSOCIATED WITH THIS FEATURE WILL MOVE INTO THE GREAT LAKES REGION SUNDAY NIGHT AND BRING A CHANCE FOR RAIN TO THE AREA. STRONG WARM AIR ADVECTION AHEAD OF THIS SYSTEM WILL HAVE TEMPS CLIMBING INTO THE 50S IN THE SOUTHERN CWA SUNDAY...BUT THEN SHARPLY COLDER BEHIND COLD FRONT SUNDAY NIGHT WILL TRANSITION PRECIP BACK OVER TO SNOW BEFORE ENDING. AS THIS FIRST SYSTEM IS MAKING ITS WAY ACROSS OUR AREA...NEXT SHORT WAVE WILL BE COMING ONSHORE IN THE PACIFIC NORTHWEST AND DIGGING SOUTHEAST INTO THE FOUR CORNERS MONDAY NIGHT/TUESDAY MORNING. SURFACE REFLECTION WITH THIS NEXT SYSTEM HAS INVERTED TROF EXTENDING UP INTO THE OHIO VALLEY AND OVERRUNNING AHEAD OF THIS FEATURE WILL BRING PRECIP CHANCES BACK INTO THE AREA EARLY NEXT WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 548 PM EST WED FEB 24 2016 LOW LIFTING NE INTO LAKE ERIE THIS EVE WITH COLDER AIR WRAPPING AROUND INTO NE INDIANA CAUSING RAIN TO CHANGE TO SNOW AT FWA. LARGE DEFORMATION ZONE ASSOCIATED WITH THIS DEEP LOW WILL CONT TO CAUSE SNOW OVERNIGHT WITH VSBYS FURTHER DECREASED BY BLSN AS STRONG N-NW WINDS CONT. IFR/LIFR CONDITIONS OVERNIGHT SHOULD IMPROVE TO VFR BY EARLY THU AFTN AS SNOW ASSOCIATED WITH THE DEPARTING LOW MOVES OUT OF THE AREA AND NW WINDS BEGIN TO DIMINISH. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR INZ009-018- 025>027-032>034. WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR INZ005>008-016- 017-022>024. WINTER STORM WARNING FROM 10 PM EST /9 PM CST/ THIS EVENING TO 4 PM EST /3 PM CST/ THURSDAY FOR INZ003-004-012>015-020. BLIZZARD WARNING UNTIL 10 PM EST /9 PM CST/ THIS EVENING FOR INZ003-004-012>015-020. MI...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR MIZ077>081. OH...WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR OHZ002-005- 016-025. WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR OHZ001-004- 015-024. LM...STORM WARNING UNTIL 7 AM EST THURSDAY FOR LMZ043-046. && $$ SYNOPSIS...LOTHAMER SHORT TERM...LASHLEY LONG TERM...JAL AVIATION...JT VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
412 PM EST WED FEB 24 2016 .SYNOPSIS... ISSUED AT 410 PM EST WED FEB 24 2016 SNOW IS EXPECTED TO CONTINUE TONIGHT INTO THURSDAY MORNING BEFORE DIMINISHING. STRONG NORTH TO NORTHWEST WINDS OF 20 TO 30 MPH WITH GUSTS TO 35 MPH WILL CREATE BLOWING AND DRIFTING SNOW. ROADS WILL BE SNOW COVERED SLICK AND HAZARDOUS. BLIZZARD CONDITIONS ACROSS NORTHWEST INDIANA AND NORTHEAST ILLINOIS MAY MAKE TRAVEL IMPOSSIBLE ON SOME ROADS. REFER TO THE LATEST WINTER WEATHER PRODUCTS FOR MORE INFORMATION. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 405 PM EST WED FEB 24 2016 WATER VAPOR SHOWS UPPER CIRCULATION OVER SOUTHERN INDIANA WITH DRY SLOT DRIVING INTO NORTHEAST INDIANA AND NORTHWEST OHIO THIS AFTERNOON. SURFACE LOW WAS MOVING THROUGH SOUTHWEST OHIO AND EXPECTED TO LIFT TOWARD NORTHEAST OHIO THIS EVENING. IMPRESSIVE COUPLED UPPER LEVEL JET PROVIDED FOCUS FOR STRONG ASCENT TODAY WHICH QUICKLY COOLED THE COLUMN AND LED TO RAPID SNOW DEVELOPMENT NORTHWEST HALF OF THE AREA. THIS CERTAINLY HAS BEEN AN INTERESTING EVENT TO WATCH UNFOLD. HIGH DGZ...STRONG WINDS AND SATURATED COLUMN BELOW DGZ LED TO AN INTERESTING PATTERN TODAY WITH PCPN TYPES AND ACCUMULATIONS. OBSERVATIONS AT KIWX SAW SNOWFLAKE SIZE AND PRECIPITATION INTENSITY CHANGE DRAMATICALLY IN JUST A MATTER OF MINUTES. BANDS OF STRONGER SNOW AND DEEPER LIFT PRODUCED LARGE SNOWFLAKES WHILE INTERMITTENT PERIODS BETWEEN HEAVIER BANDS SAW SNOWFLAKE SIZE DWINDLE TO VERY FINE FLAKES AND EVEN SNOW PELLETS AND SLEET AT TIMES WITH SOME MELTING AND REFREEZING. TO OUR SOUTHEAST...WARM LAYER CHANGED PCPN OVER TO RAIN BEFORE DRY SLOT ENDED PCPN ENTIRELY. WHILE MUCH OF NORTHWEST AREA HAS SEEN THE HEAVY SNOWFALL TODAY...REPORTS FROM KSBN AND METRO AREA HAVE BEEN ON THE LIGHT SIDE WITH JUST A COUPLE INCHES REPORTED THROUGH MID AFTERNOON. WITH SFC TEMPS ABOVE FREEZING AND URBAN SETTING THERE MAY HAVE BEEN FASTER COMPACTION AND MELTING PROCESSES WITH SNOW ON GROUND COMPARED TO MORE RURAL AREAS. REST OF EVENING WILL SEE DRY SLOT FILL IN AS EXPANDING AREA OF PRECIPITATION TO OUR SOUTH ROTATES NORTH. DEFORMATION ZONE TO EXPAND EAST ACROSS THE AREA AS LOW PULLS AWAY. COLDER AIR WILL EXPAND EAST AND SHOULD CHANGE PCPN TYPE TO ALL SNOW BY MID EVENING IN FAR EAST. RUC AND HRRR HAD A GOOD HANDLE ON PCPN TYPES TODAY AND USED THESE ALONG WITH NAM12 BLENDED FOR TIMING OF CHANGEOVER IN POWT PROCESS FOR FORECAST GRIDS. LIQUID SNOW RATIOS HAVE BEEN LOW AS EXPECTED WITH AROUND 10 TO 1 AVERAGE. SHOULD SEE THESE IMPROVE OVERNIGHT WITH SLIGHTLY COLDER AIR AND DGZ LOWERING. LAKE ENHANCED SNOW BAND STILL EXECTED TO SWING OFF THE LAKE INTO NW AND NC INDIANA WITH STRONG CYCLONIC FLOW. THIS SHOULD LEAD TO ADDITIONAL MODERATE TO HEAVY BURST OF SNOW. OVERALL INHERITED ACCUMS LOOK GOOD WITH REPORTS RECEIVED ALREADY...TOTAL ACCUMS AROUND A FOOT STILL POSSIBLE NW INDIANA TO SW MICHIGAN BY THURSDAY AFTERNOON WHEN SNOW COMES TO AN END. HEAVY WET SNOW ALONG WITH WINDS JUST BELOW BLIZZARD CRITERIA HAS KEPT NW AREAS FROM SEEING TRUE BLIZZARD CONDITIONS. HOWEVER...REPORTS OF WHITEOUT CONDITIONS AT TIMES WITH NEAR BLIZZARD CONDITIONS WARRANT KEEPING THE BZW IN PLACE THROUGH THE EVENING. SOME STRONGER GUSTS STILL POSSIBLE THIS EVENING WITH GRADIENT AS WELL. WINTER STORM WARNING REMAINS INTACT AND EXPANDED ADVISORY EAST FOR TONIGHT AND THURSDAY FOR COMBINATION OF ADDITIONAL SNOWFALL AND STRONG WINDS CREATING BLOWING AND DRIFTING ISSUES. && .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 405 PM EST WED FEB 24 2016 FORECAST PERIOD TO BEGIN ON THE QUIET SIDE FRIDAY WITH DIMINISHING LAKE EFFECT SNOW SHOWERS AS SURFACE RIDGE AXIS SHIFT EASTWARD AND FLOW QUICKLY BACKS AROUND TO THE W/SW. DRY WEATHER WILL CONTINUE THROUGH SATURDAY WITH SEASONABLE TEMPS. OVERALL PATTERN NOT CHANGING MUCH IN THE EXTENDED PERIOD WITH PERSISTENT UPPER LOWS OVER THE HUDSON BAY AND ALEUTIANS AND UPPER RIDGE REMAINING OVER THE WESTERN US. FIRST IN A SERIES OF SHORT WAVES WILL BE ROTATING OUT OF ALEUTIAN LOW AND ENTERING WEST COAST FRIDAY NIGHT. THIS WILL UNDERCUT THE WESTERN RIDGE AND MOVE INTO THE CENTRAL PLAINS SUNDAY MORNING. DEEPENING SURFACE LOW ASSOCIATED WITH THIS FEATURE WILL MOVE INTO THE GREAT LAKES REGION SUNDAY NIGHT AND BRING A CHANCE FOR RAIN TO THE AREA. STRONG WARM AIR ADVECTION AHEAD OF THIS SYSTEM WILL HAVE TEMPS CLIMBING INTO THE 50S IN THE SOUTHERN CWA SUNDAY...BUT THEN SHARPLY COLDER BEHIND COLD FRONT SUNDAY NIGHT WILL TRANSITION PRECIP BACK OVER TO SNOW BEFORE ENDING. AS THIS FIRST SYSTEM IS MAKING ITS WAY ACROSS OUR AREA...NEXT SHORT WAVE WILL BE COMING ONSHORE IN THE PACIFIC NORTHWEST AND DIGGING SOUTHEAST INTO THE FOUR CORNERS MONDAY NIGHT/TUESDAY MORNING. SURFACE REFLECTION WITH THIS NEXT SYSTEM HAS INVERTED TROF EXTENDING UP INTO THE OHIO VALLEY AND OVERRUNNING AHEAD OF THIS FEATURE WILL BRING PRECIP CHANCES BACK INTO THE AREA EARLY NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1234 PM EST WED FEB 24 2016 CONTINUED IFR/LIFR CONDITIONS TO PREVAIL OVER THE FORECAST PERIOD. DEFORMATION AXIS IS BEGINNING TO SETUP FROM KSLO-KRZL-KAZO. THIS WILL DRIFT LITTLE OVER THE NEXT 12 TO 18 HOURS AS THE SURFACE LOW LIFTS INTO SOUTHERN INDIANA AND OHIO. ABUNDANT ISENTROPIC ASCENT AND DEEP COLD AIR WILL FAVOR SNOW ALONG THE DEFORMATION AXIS. DRY INTRUSION AND COLD MID-LEVEL CIRCULATION CENTER WILL FAVOR CONVECTIVE DEVELOPMENT...ESPECIALLY ON THE EASTERN EDGE OF THE DEFORMATION AXIS. ISOLD TSSN CANNOT BE RULED OUT. OVERNIGHT AS THE COOLING AND MIXING OCCUR, EXPECT TO SEE MORE WIDESPREAD LIGHT SNOW AND IFR/LIFR CIGS/VSBY OVER ALL OF THE FORECAST AREA. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR INZ009-018- 025>027-032>034. WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR INZ005>008-016- 017-022>024. WINTER STORM WARNING FROM 10 PM EST /9 PM CST/ THIS EVENING TO 4 PM EST /3 PM CST/ THURSDAY FOR INZ003-004-012>015-020. BLIZZARD WARNING UNTIL 10 PM EST /9 PM CST/ THIS EVENING FOR INZ003-004-012>015-020. MI...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR MIZ077>081. OH...WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR OHZ002-005- 016-025. WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR OHZ001-004- 015-024. LM...STORM WARNING UNTIL 7 AM EST THURSDAY FOR LMZ043-046. && $$ SYNOPSIS...LOTHAMER SHORT TERM...LASHLEY LONG TERM...JAL AVIATION...LEWIS VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
245 PM EST WED FEB 24 2016 .UPDATE... THE LONG TERM SECTION HAS BEEN UPDATED BELOW && .SYNOPSIS... ISSUED AT 409 AM EST WED FEB 24 2016 RAIN CHANGES TO WINTER STORM CONDITIONS ACROSS MUCH OF CENTRAL INDIANA TODAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE OHIO VALLEY. STRONG WIND GUSTS AROUND 30-45 MPH ARE EXPECTED TO LAST FROM NOW THROUGH MUCH OF THE DAY ON THURSDAY. AFTER SOME HEAVY SNOW OVER PARTS OF THE AREA TODAY AND TONIGHT COULD SEE SOME SNOW SHOWERS WITH SQUALLS THURSDAY BEFORE THE SYSTEM FINALLY MOVES OUT AND DRY WEATHER REPLACES IT. MUCH WARMER FOR THE WEEKEND THEN SOME SMALLER RAIN OR RAIN SNOW MIX CHANCES OFF AND ON SUNDAY THROUGH TUESDAY. && .NEAR TERM /TODAY AND TONIGHT/... ISSUED AT 1032 AM EST WED FEB 24 2016 DECIDED TO START THE WINTER HEADLINES FOR TODAY A FEW HOURS EARLY AS WE WERE GETTING REPORTS OF A MIXTURE OF PRECIPITATION AND ICE COVERING TREES AND POWER LINES IN MUCH OF THE WINTER STORM WARNING AND ADVISORY AREA. SOME SNOW AND ICE WAS ALSO BEGINNING TO ACCUMULATE ON ROADWAYS IN A FEW LOCATIONS. WITH THAT IN MIND...THE THREAT OF POWER OUTAGE IMPACTS WEIGHED HEAVILY IN THE DECISION TO START THE HEADLINES EARLY. ALSO...EXPANDED THE WINTER WEATHER ADVISORY TO THE NORTHWEST TO INCLUDE HANCOCK...DELAWARE...HENRY AND RANDOLPH COUNTIES AS ELEVATED SURFACES WERE ALSO EXPERIENCING ICE ACCUMULATION. FOR THE MID- MORNING UPDATE...INCLUDED A CHANCE OF FREEZING RAIN TO THE RAIN SNOW MIX THAT WAS PREVIOUSLY FORECAST IN THE GRIDS. HAVE SEEN MAINLY SNOW TO THE NORTHWEST OVER WARREN AND PORTIONS OF TIPPECANOE...FOUNTAIN AND VERMILLION COUNTIES THIS MORNING. ALREADY HAD A REPORT OF AN INCH AND A HALF OF SNOW OUT OF WEST LAFAYETTE AROUND 1045 AM. FORECASTED SNOW AMOUNTS HAVE REMAINED SIMILAR TO THE PREVIOUS FORECAST. THE PREVIOUS DISCUSSION FOLLOWS... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON CURRENT STORM. GENERALLY STUCK CLOSE TO A NAM/RAP BLEND EARLY WITH THE HRRR SHOWING SOME STRANGE MOVEMENT TO THE SURFACE LOW AND NAM/RAP BOTH INITIALIZING WELL. FOR TONIGHT LEANED ON CONSENSUS. HAVE ALREADY SEEN SOME REPORTS OF SNOW MIXING IN BUT IT HAS GENERALLY BEEN PRETTY BRIEF WITH THE WARM AIR AND MOISTURE ADVECTING EVER FURTHER NORTHWARD. HAVEN/T SEEN ANY SLEET THUS FAR...AND FORECAST SOUNDINGS LOOK MUCH LESS CONDUCIVE FOR THIS THAN PREVIOUS RUNS. THUS TOOK IT OUT. NOT COMPLETELY RULING IT OUT BUT THINK IF IT HAPPENS WILL BE RELATIVELY BRIEF. STRONG FRONTOGENESIS OVER THE AREA CURRENTLY PRODUCING SOME GOOD RAIN ACROSS THE AREA. THIS MOVES NORTH AND COULD SEE MORE SPOTTY COVERAGE FOR A FEW HOURS THIS MORNING BEFORE MORE SIGNIFICANT UPPER FORCING KICKS IN. ALSO DEFORMATION ZONE SHOULD SET UP AND THIS STILL LOOKS LIKE IT WILL PRODUCE HEAVY SNOW OVER THE NORTHWEST COUNTIES. DID NOT MAKE SIGNIFICANT CHANGES TO STORM TOTAL SNOWFALL AMOUNTS...BUT DID INCREASE AMOUNTS ENOUGH IN HOWARD COUNTY TO UPGRADE THEM FROM ADVISORY TO WINTER STORM WARNING. ALSO ADDED MADISON COUNTY TO THE ADVISORY WITH SIMILAR SNOWFALL TOTALS TO THOSE EXPECTED IN THE REST OF THE ADVISORY AREA. EAST OF THERE...STILL NOT CONFIDENT ENOUGH ON TIMING OF CHANGEOVER TO SNOW AND TOTAL AMOUNTS TO EXPAND THERE JUST YET. WIND GUSTS TODAY WILL BE IN THE 30-45 MPH RANGE AND COMBINED WITH HEAVY SNOW BAND THAT CURRENTLY LOOKS TO SET UP OVER PARTS OF ILLINOIS AND NORTHWEST INDIANA HAVE CHANGED WARREN COUNTY OVER TO A BLIZZARD WARNING. ELSEWHERE WAS NOT CONFIDENT ENOUGH OF HEAVY SNOW CONDITIONS FOR LONG ENOUGH TO EXPECT THE NEAR ZERO VISIBILITIES TO LAST FOR HOURS...BUT ALSO WOULD NOT BE SURPRISED TO SEE THEM THERE OFF AND ON FOR A TIME THIS AFTERNOON/EVENING. CHANGEOVER LOOKS A LITTLE FASTER THAN PREVIOUS FORECAST BUT NOT A LOT. STILL BY MIDMORNING OVER THE NORTHWEST...AFTERNOON CENTRAL...AND NOT UNTIL TONIGHT IN THE EAST AND SOUTHEAST. DECENT UPPER FORCING LASTS THROUGH TONIGHT ACROSS THE AREA BUT DEFORMATION ZONE SHEARS SOMEWHAT AND EXPECT MUCH LOWER SNOWFALL RATES THAN THOSE SEEN DURING THE PERIOD OF MAX SNOWFALL/BANDING TODAY IN THE NORTHWEST. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON SNOW POTENTIAL AND WIND GUSTS THURSDAY. MODELS ARE IN RELATIVELY GOOD AGREEMENT AND GENERALLY USED CONSENSUS. FOR SNOW POPS ON THURSDAY DID INCREASE FROM GUIDANCE. STILL SEE A SHORTWAVE SPOKE ON THE BACK SIDE OF THE SYSTEM THAT SWINGS THROUGH THE TROUGH TO PROVIDE SOME FORCING. SNOW SQUALL PARAMETER JUMPS UP DURING THIS TIME DUE TO SHARP LAPSE RATES SO COMBINED WITH THE FORCING EXPECT TO SEE SNOW SHOWERS DEVELOP. CONTINUED TIGHT PRESSURE GRADIENT ACROSS THE AREA WILL PRODUCE WIND GUSTS IN THE 30-40 MPH RANGE UNTIL EVENING WHEN THE GRADIENT FINALLY SLACKENS AND COMBINING THIS WITH SNOW EXPECT TO SEE SPOTS WHERE VISIBILITIES DROP DRASTICALLY FOR SHORT PERIODS OF TIME. MAY HAVE TO WIND UP EXPANDING ADVISORY BOTH EASTWARD AND IN TIME DEPENDING ON HOW SYSTEM PLAYS OUT...BUT WITH CONFIDENCE NOT AT SLAM DUNK LEVELS AND STILL 24+ HOURS OUT WILL LET NEXT SHIFT HAVE A LOOK AT LATEST GUIDANCE AND GO FROM THERE. MODELS ARE IN AGREEMENT ON DRY WEATHER THURSDAY NIGHT ON...WITH THE EXCEPTION OF A SLIGHT CHANCE FOR SNOW IN THE FAR NORTHEAST EARLY THURSDAY NIGHT. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... ISSUED AT 245 PM EST WED FEB 24 2016 TEMPERATURE ROLLER COASTER ON THE HORIZON FOR THE EXTENDED PERIOD WITH A QUICK MOVING LOW PRESSURE BRINGING LOW CHANCE FOR POPS LATE WEEKEND...THEN A MORE SUBSTANTIAL THREAT FOR PRECIPITATION FOR THE MIDDLE OF NEXT WEEK AS AN UPPER WAVE DIVES OUT OF THE ROCKIES AND INTERACTS WITH A FRONTAL BOUNDARY. UPPER RIDGING WILL DEVELOP AHEAD OF THE SURFACE LOW TRACKING ACROSS THE GREAT LAKES ON SUNDAY. STRONG WARM ADVECTION AND SOUTHERLY FLOW WILL ENABLE A NICE WARMUP ACROSS THE REGION WITH HIGHS INTO THE 60S ALONG AND SOUTH OF I-70. PRECIP WILL BE PRIMARILY IN THE FORM OF RAIN...ALTHOUGH LOW LEVEL THERMALS BECOME SUPPORTIVE OF SNOW MIXING IN OVER NORTHERN COUNTIES BEFORE PRECIP ENDS LATE SUNDAY NIGHT. HIGH PRESSURE IS EXPECTED WITH DRY WEATHER MONDAY BEFORE RAIN CHANCES RETURN TUESDAY AND WEDNESDAY AS A FRONTAL BOUNDARY SETS UP NEAR THE OHIO RIVER. THE AFOREMENTIONED UPPER WAVE WILL KICK OUT OF THE ROCKIES AND SPIN UP A SURFACE WAVE LIFTING INTO THE OHIO VALLEY BY THE END OF THE PERIOD. PLENTY OF UNCERTAINTY AT THIS EARLY STAGE WITH EXTENDED MODELS OFFERING A PLETHORA OF SOLUTIONS WITH RESPECT TO LOCATION OF THE FRONTAL BOUNDARY AND TIMING OF THE SURFACE WAVES TRACKING ALONG IT WHICH WILL HAVE AN EFFECT ON PRECIP TYPE...AMOUNTS AND IMPACT. HIGHS WILL GENERALLY REMAIN NEAR TO ABOVE NORMAL THROUGH THE FIRST HALF OF NEXT WEEK. && .AVIATION /DISCUSSION FOR 241800Z TAF ISSUANCE/... ISSUED AT 1225 PM EST WED FEB 24 2016 POOR FLYING CONDITIONS WILL CONTINUE THROUGHOUT MUCH OF THE FORECAST PERIOD. STRONG LOW PRESSURE OVER FAR SOUTHERN INDIANA TRACKING NORTHEAST EARLY THIS AFTERNOON WITH A WARM FRONT LIFTING INTO WESTERN OHIO. BULK OF THE STEADIER PRECIP HAS SHIFTED INTO THE NORTHERN WABASH VALLEY IN CLOSER PROXIMITY TO AN INTENSE MID LEVEL DEFORMATION BAND. THIS IS FALLING PREDOMINANTLY AS SNOW OCCASIONALLY MIXING WITH SLEET AND/OR RAIN. AS THE LOW LIFTS NORTHEAST THROUGH THE AFTERNOON...THE WELL DEFINED TROWAL AT 850MB WILL LIFT OUT ALONG WITH IT. COLDER AIRMASS WILL TAKE OVER WITH PRECIPITATION TRANSITIONING TO ALL SNOW. AT KLAF...EXPECT HEAVY SNOW TO IMPACT THE TERMINAL FOR THE NEXT SEVERAL HOURS AS THE DEFORMATION BAND INFLUENCES SNOW RATES. PRECIP SHOULD CHANGE TO SNOW IN KHUF BY 19-20Z...AND KBMG AND KIND BETWEEN 20 AND 22Z. ONCE THE CHANGE TO SNOW TAKES PLACE...EXPECT A PERIOD WITH SUB-IFR VISIBILITIES AND HEAVIER SNOWS INTO THE EVENING. LIGHTER SNOWS WILL CONTINUE OVERNIGHT WITH A POTENTIAL FOR SCATTERED SNOW SHOWERS AND SQUALLS ON THURSDAY AS A SURFACE TROUGH AND WAVE ALOFT ROTATE THROUGH THE AREA ON THE BACK SIDE OF THE DEPARTING STORM. WINDS WILL REMAIN A SIGNIFICANT FACTOR THROUGH THE FORECAST PERIOD...WITH SUSTAINED IN EXCESS OF 20KTS AND GUSTS AT 30-35KTS POSSIBLE INTO EARLY THURSDAY. N/NE WINDS THIS AFTERNOON WILL BACK TO NORTHWEST THEN W/NW BY THURSDAY AS THE LOW PULLS AWAY TO THE NORTHEAST. && .IND WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 1 PM EST THURSDAY FOR INZ037>042- 045>049-051>054-060-061-067. WINTER STORM WARNING UNTIL 1 PM EST THURSDAY FOR INZ021-029>031- 035-036-043-044. BLIZZARD WARNING UNTIL 1 AM EST THURSDAY FOR INZ028. && $$ SYNOPSIS...CP NEAR TERM...MRD/CP SHORT TERM...CP LONG TERM....RYAN AVIATION...RYAN
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1240 PM EST WED FEB 24 2016 .SYNOPSIS... ISSUED AT 1020 AM EST WED FEB 24 2016 STRONG LOW PRESSURE WILL LIFT UP ACROSS THE OHIO VALLEY TODAY...SPREADING PRECIPITATION NORTH ACROSS THE AREA THROUGH MID MORNING. HEAVY SNOW IS EXPECTED ACROSS NORTHEAST ILLINOIS...NORTHWEST INDIANA AND SOUTHWEST LOWER MICHIGAN. A MIX OF PRECIPITATION IS EXPECTED ELSEWHERE TODAY OVER CENTRAL AND EASTERN INDIANA WITH MAINLY RAIN OVER NORTHWEST OHIO. RAIN WILL TRANSITION BACK TO SNOW THIS AFTERNOON AND EVENING FROM WEST TO EAST. MULTIPLE WINTER WEATHER HEADLINES ARE IN EFFECT ACROSS THE REGION FOR TODAY THROUGH THURSDAY. TRAVEL WILL BE DIFFICULT AT TIMES ESPECIALLY OVER NORTHEAST ILLINOIS AND NORTHWEST INDIANA WITH BLIZZARD CONDITIONS LIKELY. && .UPDATE... ISSUED AT 1020 AM EST WED FEB 24 2016 NO SIGNIFICANT CHANGES EXPECTED TO FORECAST AT THIS TIME. WINDS HAVE BEEN PICKING UP THIS MORNING WITH GUSTS TO BETWEEN 30 AND 40 MPH. KFWA ACTUALLY HAD A GUST TO 45 MPH. VISIBILITIES HAVE NOT BEEN REDUCED MUCH BELOW ONE HALF MILE YET AND THIS IS A CONCERN. STILL EXPECTING HEAVIEST SNOW TO ROTATE INTO NW AREAS THIS AFTERNOON WHILE STRONG PRESSURE GRADIENT PROVIDES INCREASE IN SUSTAINED WIND AND GUSTS. HAND ANALYSIS OF 15Z SFC MAP SHOWS SFC LOW JUST WEST OF KSDF WITH AN ELONGATED AXIS OF LOW PRESSURE STRETCHING NORTHEAST ALONG OH RIVER. BEST PRESSURE FALLS NEAR CLE WHICH SUPPORTS LATEST NAM AND MANY OF THE HIRES GUIDANCE OUTPUT. MAIN CONCERN RIGHT NOW REMAINS ALONG SHARP TRANSITION ZONE BETWEEN RAIN AND SNOW OVER CENTRAL FORECAST AREA. WARNING SEEMS TO HAVE THIS HANDLED WELL FOR NOW WITH ONLY QUESTION BEING IN THE NORTHEAST. LATEST NAM12 SUGGEST PCPN IN WILLIAMS COUNTY MAY REMAIN ALL SNOW WITH RAIN SOUTH OF THERE THIS AFTERNOON. REGIONAL RADAR MOSAIC SHOWING DRY SLOT WORKING NORTH AND HAVING AN IMPACT ON PCPN AND RADAR RETURNS WITH DIMINISHING TRENDS. THIS SHOULD HELP LIMIT AMOUNTS WHERE NO HEADLINES IN EFFECT AND SNOW IS FALLING. THUS PLAN TO KEEP WILLIAMS IN AN ADVISORY BUT WILL BE MONITORING THIS AREA CLOSELY. SOME SLEET REPORTS BEING RECEIVED MAINLY ALONG BACK EDGE OF MORE SOLID PCPN SHIELD WHERE DRY SLOT POKING IN. SEEING SOME ADDITIONAL EVAP COOLING IN LOW LEVELS AND LIKELY ALLOWING FOR SOME REFREEZING BEFORE REACHING GROUND. WILL BE MONITORING LATEST 12Z DATA CLOSELY FOR ANY ADDITIONAL CHANGES TO HEADLINES LATER THIS AFTERNOON. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 545 AM EST WED FEB 24 2016 INTENSE SW OVR THE MID MS VALLEY W/ATTENDANT 990MB SFC REFLECTION OVR NW TN DEEPENING RAPIDLY ERLY THIS MORNING. BROAD ARC OF 6MB/3HR PRES FALLS INTO SRN IN/SW OH WITHIN FOCUSED INTENSE WAA ZONE SPURNING WIDESPREAD MOD-HVY RAIN FM ERN IN IN SWD INTO NRN KY. TIGHT/COHERENT NR TERM HIGHRES GUIDANCE SPOT ON W/NWD REACH OF CURRENT PRECIP SHIELD AND PLACEMENT OF SFC LOW...FURTHER ACCENTUATED BY TRENDS FM RAP GUIDANCE SINCE 00Z...SUGGEST FEW CHGS WARRANTED TO EXISTING HEADLINES ALTHOUGH WILL ADD STEUBEN AND HILLSDALE TO CURRENT WARNING HEADLINE AND IN COORDINATION W/ILX/IND/LOT UPGRADE NW IN ZONES TO BZW. SFC LOW OVR NW TN WILL RAPIDLY LIFT NEWD TDA...REACHING NR KCLE BY 00Z AS TROUGH ALOFT TURNS NEGATIVELY TILTED. THIS WILL PROLONG BOTH STG GRADIENT WINDS AND MOD-HVY SNOW ACRS NW HALF. HWVR EWD WRAP OF SUBTROPICAL JET THROUGH ERN OH AND WWD PLACEMENT OF COUPLING W/NRN JET ACRS THE UPR LAKES SUGGESTS SOME DRY SLOTTING AND EVEN SOME LIMITED POTENTIAL FOR THUNDER ACRS WRN OH THIS AFTERNOON. OTRWS COUPLED JET WILL DRIVE INTENSE/DEEP VERTICAL MOTION ESP FM MID MORNING THROUGH LT AFTN NW HALF W/SHARP EWD SNOW CUTOFF TO NOTHING XPCD AS GENERAL STEADYSTATE RAIN/SNOW LINE STRETCHES FM LOGANSPORT- WARSAW-COLDWATER LINE. IT SHLD BE NOTED HWVR THAT RUC CONTS TO TREND A BIT EWD OF THIS LINE AND IN CONCERT W/AGREEABLE NOD FM 06Z NAM WILL SHIFT A BIT EAST. THAT SAID...BLIZZARD CONDS LIKELY NW ZONES COLLOCATED WITHIN INTENSE DEFORMATION SNOW BAND AND MOST INTENSE GRADIENT FLW. XPC SNOWFALL RATES OF 1-2"/HR LIKELY HERE MID MORNING THROUGH LT AFTN. SECONDARY CONCERN LIES W/EWD PULLOUT OF INTENSE SFC CYCLONE OVERNIGHT AND WRN BOUND OF LK ENHANCING MID LVL MSTR PLUME. FLW SLW TO RELAX AND BLIZZARD WARNING COULD BE EXTENDED PENDING HOW THINGS SHAKE OUT TDA AS SOME SIG ACCUMULATION POTENTIAL EXISTS OVR FAR NW ZONES YET DIMINISHES QUICKLY W/INLAND EXTENT. OTRWS STG GRADIENT FLW REMAINS W/RISE COUPLET SLW TO LIFT OUT THROUGH OH OVERNIGHT WHICH SHLD YIELD CONTD AREAS OF BLOWING SNOW. LK ENHANCEMENT SPREADS FURTHER INLAND THU AM AS LL FLW TURNS NWRLY AND XPC MOST AREAS WILL SEE A GENERAL 1-3 INCH ADDNL ACCUM W/CONTD GUSTY NW WINDS NOT DIMINISHING UNTIL AFTN. && .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 545 AM EST WED FEB 24 2016 REST OF THE PERIOD FAIRLY UNEVENTFUL. CHANCE FOR A FEW LAKE EFFECT SNOW SHOWERS THURSDAY NIGHT INTO FRIDAY AS 850MB TEMPS DROP TO AROUND -13C. HOWEVER...FORECAST SOUNDINGS SHOW INVERSION HEIGHTS ARE PRETTY LOW (AROUND 4 KFT) WITH A FAIR AMOUNT OF DRY AIR ENTRAINMENT. 0-2KM DELTA THETA-E VALUES REMAIN ABOVE ZERO AND PERSISTENT NORTHWEST GRADIENT WILL PREVENT ANY TYPE OF BAND ORGANIZATION. DID RAISE POPS JUST A LITTLE FOR LATE THURSDAY NIGHT/FRIDAY MORNING BUT DONT EXPECT MUCH ACCUMULATION...A HALF INCH AT BEST. ANY RESIDUAL LAKE EFFECT SNOW SHOWERS WILL END BY FRIDAY AFTERNOON AS FLOW BACKS WEST AND EVENTUALLY SOUTHWEST. WILL STILL BE A FAIRLY CHILLY DAY THOUGH WITH MOSTLY CLOUDY SKIES AND HIGHS AT OR BELOW FREEZING. AFTER A FAIRLY PLEASANT SATURDAY...NEXT CHANCE OF PRECIP ARRIVES LATE SUNDAY. PRETTY HEALTHY SHORTWAVE SET TO SWING THROUGH THE REGION WITH UPPER JET SUPPORT AND GOOD PV ADVECTION BUT EXACT TRACK REMAINS UNCERTAIN. DOES APPEAR TO BE VERY WARM AHEAD OF THE FRONT WITH TEMPS POTENTIALLY WELL INTO THE 50S ON SUNDAY...SUPPORTING RAIN AS PTYPE IF ANYTHING OCCURS. THERE IS A CHANCE FOR A QUICK SHOT OF LIGHT SNOW IN OUR NORTHERN COUNTIES SUNDAY NIGHT IF POSTFRONTAL DEFORMATION BAND SWINGS THROUGH THE AREA BUT THAT IS QUESTIONABLE AT THIS POINT...AS ARE THERMAL PROFILES. REGARDLESS...ANY SNOW THAT DOES FALL SHOULD BE LIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1234 PM EST WED FEB 24 2016 CONTINUED IFR/LIFR CONDITIONS TO PREVAIL OVER THE FORECAST PERIOD. DEFORMATION AXIS IS BEGINNING TO SETUP FROM KSLO-KRZL-KAZO. THIS WILL DRIFT LITTLE OVER THE NEXT 12 TO 18 HOURS AS THE SURFACE LOW LIFTS INTO SOUTHERN INDIANA AND OHIO. ABUNDANT ISENTROPIC ASCENT AND DEEP COLD AIR WILL FAVOR SNOW ALONG THE DEFORMATION AXIS. DRY INTRUSION AND COLD MID-LEVEL CIRCULATION CENTER WILL FAVOR CONVECTIVE DEVELOPMENT...ESPECIALLY ON THE EASTERN EDGE OF THE DEFORMATION AXIS. ISOLD TSSN CANNOT BE RULED OUT. OVERNIGHT AS THE COOLING AND MIXING OCCUR, EXPECT TO SEE MORE WIDESPREAD LIGHT SNOW AND IFR/LIFR CIGS/VSBY OVER ALL OF THE FORECAST AREA. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR INZ005>008-016- 017-022>024. WINTER STORM WARNING FROM 10 PM EST /9 PM CST/ THIS EVENING TO 4 PM EST /3 PM CST/ THURSDAY FOR INZ003-004-012>015-020. BLIZZARD WARNING UNTIL 10 PM EST /9 PM CST/ THIS EVENING FOR INZ003-004-012>015-020. WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR INZ009. WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 4 PM EST THURSDAY FOR INZ018-025-032. MI...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR MIZ077>081. OH...WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR OHZ001. LM...STORM WARNING UNTIL 7 AM EST THURSDAY FOR LMZ043-046. && $$ UPDATE...LASHLEY SYNOPSIS...LOTHAMER SHORT TERM...T LONG TERM...AGD AVIATION...LEWIS VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1225 PM EST WED FEB 24 2016 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW && .SYNOPSIS... ISSUED AT 409 AM EST WED FEB 24 2016 RAIN CHANGES TO WINTER STORM CONDITIONS ACROSS MUCH OF CENTRAL INDIANA TODAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE OHIO VALLEY. STRONG WIND GUSTS AROUND 30-45 MPH ARE EXPECTED TO LAST FROM NOW THROUGH MUCH OF THE DAY ON THURSDAY. AFTER SOME HEAVY SNOW OVER PARTS OF THE AREA TODAY AND TONIGHT COULD SEE SOME SNOW SHOWERS WITH SQUALLS THURSDAY BEFORE THE SYSTEM FINALLY MOVES OUT AND DRY WEATHER REPLACES IT. MUCH WARMER FOR THE WEEKEND THEN SOME SMALLER RAIN OR RAIN SNOW MIX CHANCES OFF AND ON SUNDAY THROUGH TUESDAY. && .NEAR TERM /TODAY AND TONIGHT/... ISSUED AT 1032 AM EST WED FEB 24 2016 DECIDED TO START THE WINTER HEADLINES FOR TODAY A FEW HOURS EARLY AS WE WERE GETTING REPORTS OF A MIXTURE OF PRECIPITATION AND ICE COVERING TREES AND POWER LINES IN MUCH OF THE WINTER STORM WARNING AND ADVISORY AREA. SOME SNOW AND ICE WAS ALSO BEGINNING TO ACCUMULATE ON ROADWAYS IN A FEW LOCATIONS. WITH THAT IN MIND...THE THREAT OF POWER OUTAGE IMPACTS WEIGHED HEAVILY IN THE DECISION TO START THE HEADLINES EARLY. ALSO...EXPANDED THE WINTER WEATHER ADVISORY TO THE NORTHWEST TO INCLUDE HANCOCK...DELAWARE...HENRY AND RANDOLPH COUNTIES AS ELEVATED SURFACES WERE ALSO EXPERIENCING ICE ACCUMULATION. FOR THE MID- MORNING UPDATE...INCLUDED A CHANCE OF FREEZING RAIN TO THE RAIN SNOW MIX THAT WAS PREVIOUSLY FORECAST IN THE GRIDS. HAVE SEEN MAINLY SNOW TO THE NORTHWEST OVER WARREN AND PORTIONS OF TIPPECANOE...FOUNTAIN AND VERMILLION COUNTIES THIS MORNING. ALREADY HAD A REPORT OF AN INCH AND A HALF OF SNOW OUT OF WEST LAFAYETTE AROUND 1045 AM. FORECASTED SNOW AMOUNTS HAVE REMAINED SIMILAR TO THE PREVIOUS FORECAST. THE PREVIOUS DISCUSSION FOLLOWS... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON CURRENT STORM. GENERALLY STUCK CLOSE TO A NAM/RAP BLEND EARLY WITH THE HRRR SHOWING SOME STRANGE MOVEMENT TO THE SURFACE LOW AND NAM/RAP BOTH INITIALIZING WELL. FOR TONIGHT LEANED ON CONSENSUS. HAVE ALREADY SEEN SOME REPORTS OF SNOW MIXING IN BUT IT HAS GENERALLY BEEN PRETTY BRIEF WITH THE WARM AIR AND MOISTURE ADVECTING EVER FURTHER NORTHWARD. HAVEN/T SEEN ANY SLEET THUS FAR...AND FORECAST SOUNDINGS LOOK MUCH LESS CONDUCIVE FOR THIS THAN PREVIOUS RUNS. THUS TOOK IT OUT. NOT COMPLETELY RULING IT OUT BUT THINK IF IT HAPPENS WILL BE RELATIVELY BRIEF. STRONG FRONTOGENESIS OVER THE AREA CURRENTLY PRODUCING SOME GOOD RAIN ACROSS THE AREA. THIS MOVES NORTH AND COULD SEE MORE SPOTTY COVERAGE FOR A FEW HOURS THIS MORNING BEFORE MORE SIGNIFICANT UPPER FORCING KICKS IN. ALSO DEFORMATION ZONE SHOULD SET UP AND THIS STILL LOOKS LIKE IT WILL PRODUCE HEAVY SNOW OVER THE NORTHWEST COUNTIES. DID NOT MAKE SIGNIFICANT CHANGES TO STORM TOTAL SNOWFALL AMOUNTS...BUT DID INCREASE AMOUNTS ENOUGH IN HOWARD COUNTY TO UPGRADE THEM FROM ADVISORY TO WINTER STORM WARNING. ALSO ADDED MADISON COUNTY TO THE ADVISORY WITH SIMILAR SNOWFALL TOTALS TO THOSE EXPECTED IN THE REST OF THE ADVISORY AREA. EAST OF THERE...STILL NOT CONFIDENT ENOUGH ON TIMING OF CHANGEOVER TO SNOW AND TOTAL AMOUNTS TO EXPAND THERE JUST YET. WIND GUSTS TODAY WILL BE IN THE 30-45 MPH RANGE AND COMBINED WITH HEAVY SNOW BAND THAT CURRENTLY LOOKS TO SET UP OVER PARTS OF ILLINOIS AND NORTHWEST INDIANA HAVE CHANGED WARREN COUNTY OVER TO A BLIZZARD WARNING. ELSEWHERE WAS NOT CONFIDENT ENOUGH OF HEAVY SNOW CONDITIONS FOR LONG ENOUGH TO EXPECT THE NEAR ZERO VISIBILITIES TO LAST FOR HOURS...BUT ALSO WOULD NOT BE SURPRISED TO SEE THEM THERE OFF AND ON FOR A TIME THIS AFTERNOON/EVENING. CHANGEOVER LOOKS A LITTLE FASTER THAN PREVIOUS FORECAST BUT NOT A LOT. STILL BY MIDMORNING OVER THE NORTHWEST...AFTERNOON CENTRAL...AND NOT UNTIL TONIGHT IN THE EAST AND SOUTHEAST. DECENT UPPER FORCING LASTS THROUGH TONIGHT ACROSS THE AREA BUT DEFORMATION ZONE SHEARS SOMEWHAT AND EXPECT MUCH LOWER SNOWFALL RATES THAN THOSE SEEN DURING THE PERIOD OF MAX SNOWFALL/BANDING TODAY IN THE NORTHWEST. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON SNOW POTENTIAL AND WIND GUSTS THURSDAY. MODELS ARE IN RELATIVELY GOOD AGREEMENT AND GENERALLY USED CONSENSUS. FOR SNOW POPS ON THURSDAY DID INCREASE FROM GUIDANCE. STILL SEE A SHORTWAVE SPOKE ON THE BACK SIDE OF THE SYSTEM THAT SWINGS THROUGH THE TROUGH TO PROVIDE SOME FORCING. SNOW SQUALL PARAMETER JUMPS UP DURING THIS TIME DUE TO SHARP LAPSE RATES SO COMBINED WITH THE FORCING EXPECT TO SEE SNOW SHOWERS DEVELOP. CONTINUED TIGHT PRESSURE GRADIENT ACROSS THE AREA WILL PRODUCE WIND GUSTS IN THE 30-40 MPH RANGE UNTIL EVENING WHEN THE GRADIENT FINALLY SLACKENS AND COMBINING THIS WITH SNOW EXPECT TO SEE SPOTS WHERE VISIBILITIES DROP DRASTICALLY FOR SHORT PERIODS OF TIME. MAY HAVE TO WIND UP EXPANDING ADVISORY BOTH EASTWARD AND IN TIME DEPENDING ON HOW SYSTEM PLAYS OUT...BUT WITH CONFIDENCE NOT AT SLAM DUNK LEVELS AND STILL 24+ HOURS OUT WILL LET NEXT SHIFT HAVE A LOOK AT LATEST GUIDANCE AND GO FROM THERE. MODELS ARE IN AGREEMENT ON DRY WEATHER THURSDAY NIGHT ON...WITH THE EXCEPTION OF A SLIGHT CHANCE FOR SNOW IN THE FAR NORTHEAST EARLY THURSDAY NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... ISSUED AT 330 AM EST WED FEB 24 2016 QUIETER WEATHER WILL BE THE RULE THIS WEEKEND AS THE UPPER FLOW BECOMES MORE ZONAL AND HIGH PRESSURE MOVES EAST ACROSS THE LOWER AND MIDDLE MISSISSIPPI VALLEY INTO THE SOUTHEASTERN U.S. MODELS MOVE AN AREA OF LOW PRESSURE EAST ACROSS THE SOUTHERN GREAT LAKES AND PULL A WEAK COLD FRONT THROUGH OUR REGION AROUND SUNDAY NIGHT. WILL CONTINUE LOW CHANCE POPS LATE SUNDAY THROUGH SUNDAY NIGHT. MOST MODELS INDICATE PRECIP WILL BE DONE AFTER 12Z MONDAY. WILL KEEP SLIGHT CHANCE POPS IN THE NORTH MONDAY NIGHT...BUT OVERALL MODEL TRENDS ARE DRIER UNTIL TUESDAY. ANOTHER SYSTEM WILL BE MOVING OUR WAY THE END OF DAY 7 AND THUS CONTINUE LOW CHANCES OF MAINLY RAIN. IN REGARDS TO TEMPERATURES STAYED CLOSE TO MODEL INITIALIZATION. && .AVIATION /DISCUSSION FOR 241800Z TAF ISSUANCE/... ISSUED AT 1225 PM EST WED FEB 24 2016 POOR FLYING CONDITIONS WILL CONTINUE THROUGHOUT MUCH OF THE FORECAST PERIOD. STRONG LOW PRESSURE OVER FAR SOUTHERN INDIANA TRACKING NORTHEAST EARLY THIS AFTERNOON WITH A WARM FRONT LIFTING INTO WESTERN OHIO. BULK OF THE STEADIER PRECIP HAS SHIFTED INTO THE NORTHERN WABASH VALLEY IN CLOSER PROXIMITY TO AN INTENSE MID LEVEL DEFORMATION BAND. THIS IS FALLING PREDOMINANTLY AS SNOW OCCASIONALLY MIXING WITH SLEET AND/OR RAIN. AS THE LOW LIFTS NORTHEAST THROUGH THE AFTERNOON...THE WELL DEFINED TROWAL AT 850MB WILL LIFT OUT ALONG WITH IT. COLDER AIRMASS WILL TAKE OVER WITH PRECIPITATION TRANSITIONING TO ALL SNOW. AT KLAF...EXPECT HEAVY SNOW TO IMPACT THE TERMINAL FOR THE NEXT SEVERAL HOURS AS THE DEFORMATION BAND INFLUENCES SNOW RATES. PRECIP SHOULD CHANGE TO SNOW IN KHUF BY 19-20Z...AND KBMG AND KIND BETWEEN 20 AND 22Z. ONCE THE CHANGE TO SNOW TAKES PLACE...EXPECT A PERIOD WITH SUB-IFR VISIBILITIES AND HEAVIER SNOWS INTO THE EVENING. LIGHTER SNOWS WILL CONTINUE OVERNIGHT WITH A POTENTIAL FOR SCATTERED SNOW SHOWERS AND SQUALLS ON THURSDAY AS A SURFACE TROUGH AND WAVE ALOFT ROTATE THROUGH THE AREA ON THE BACK SIDE OF THE DEPARTING STORM. WINDS WILL REMAIN A SIGNIFICANT FACTOR THROUGH THE FORECAST PERIOD...WITH SUSTAINED IN EXCESS OF 20KTS AND GUSTS AT 30-35KTS POSSIBLE INTO EARLY THURSDAY. N/NE WINDS THIS AFTERNOON WILL BACK TO NORTHWEST THEN W/NW BY THURSDAY AS THE LOW PULLS AWAY TO THE NORTHEAST. && .IND WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 1 PM EST THURSDAY FOR INZ037>042- 045>049-051>054-060-061-067. WINTER STORM WARNING UNTIL 1 PM EST THURSDAY FOR INZ021-029>031- 035-036-043-044. BLIZZARD WARNING UNTIL 1 AM EST THURSDAY FOR INZ028. && $$ SYNOPSIS...CP NEAR TERM...MRD/CP SHORT TERM...CP LONG TERM...JH AVIATION...RYAN
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1048 AM EST WED FEB 24 2016 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 409 AM EST WED FEB 24 2016 RAIN CHANGES TO WINTER STORM CONDITIONS ACROSS MUCH OF CENTRAL INDIANA TODAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE OHIO VALLEY. STRONG WIND GUSTS AROUND 30-45 MPH ARE EXPECTED TO LAST FROM NOW THROUGH MUCH OF THE DAY ON THURSDAY. AFTER SOME HEAVY SNOW OVER PARTS OF THE AREA TODAY AND TONIGHT COULD SEE SOME SNOW SHOWERS WITH SQUALLS THURSDAY BEFORE THE SYSTEM FINALLY MOVES OUT AND DRY WEATHER REPLACES IT. MUCH WARMER FOR THE WEEKEND THEN SOME SMALLER RAIN OR RAIN SNOW MIX CHANCES OFF AND ON SUNDAY THROUGH TUESDAY. && .NEAR TERM /TODAY AND TONIGHT/... ISSUED AT 1032 AM EST WED FEB 24 2016 DECIDED TO START THE WINTER HEADLINES FOR TODAY A FEW HOURS EARLY AS WE WERE GETTING REPORTS OF A MIXTURE OF PRECIPITATION AND ICE COVERING TREES AND POWER LINES IN MUCH OF THE WINTER STORM WARNING AND ADVISORY AREA. SOME SNOW AND ICE WAS ALSO BEGINNING TO ACCUMULATE ON ROADWAYS IN A FEW LOCATIONS. WITH THAT IN MIND...THE THREAT OF POWER OUTAGE IMPACTS WEIGHED HEAVILY IN THE DECISION TO START THE HEADLINES EARLY. ALSO...EXPANDED THE WINTER WEATHER ADVISORY TO THE NORTHWEST TO INCLUDE HANCOCK...DELAWARE...HENRY AND RANDOLPH COUNTIES AS ELEVATED SURFACES WERE ALSO EXPERIENCING ICE ACCUMULATION. FOR THE MID- MORNING UPDATE...INCLUDED A CHANCE OF FREEZING RAIN TO THE RAIN SNOW MIX THAT WAS PREVIOUSLY FORECAST IN THE GRIDS. HAVE SEEN MAINLY SNOW TO THE NORTHWEST OVER WARREN AND PORTIONS OF TIPPECANOE...FOUNTAIN AND VERMILLION COUNTIES THIS MORNING. ALREADY HAD A REPORT OF AN INCH AND A HALF OF SNOW OUT OF WEST LAFAYETTE AROUND 1045 AM. FORECASTED SNOW AMOUNTS HAVE REMAINED SIMILAR TO THE PREVIOUS FORECAST. THE PREVIOUS DISCUSSION FOLLOWS... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON CURRENT STORM. GENERALLY STUCK CLOSE TO A NAM/RAP BLEND EARLY WITH THE HRRR SHOWING SOME STRANGE MOVEMENT TO THE SURFACE LOW AND NAM/RAP BOTH INITIALIZING WELL. FOR TONIGHT LEANED ON CONSENSUS. HAVE ALREADY SEEN SOME REPORTS OF SNOW MIXING IN BUT IT HAS GENERALLY BEEN PRETTY BRIEF WITH THE WARM AIR AND MOISTURE ADVECTING EVER FURTHER NORTHWARD. HAVEN/T SEEN ANY SLEET THUS FAR...AND FORECAST SOUNDINGS LOOK MUCH LESS CONDUCIVE FOR THIS THAN PREVIOUS RUNS. THUS TOOK IT OUT. NOT COMPLETELY RULING IT OUT BUT THINK IF IT HAPPENS WILL BE RELATIVELY BRIEF. STRONG FRONTOGENESIS OVER THE AREA CURRENTLY PRODUCING SOME GOOD RAIN ACROSS THE AREA. THIS MOVES NORTH AND COULD SEE MORE SPOTTY COVERAGE FOR A FEW HOURS THIS MORNING BEFORE MORE SIGNIFICANT UPPER FORCING KICKS IN. ALSO DEFORMATION ZONE SHOULD SET UP AND THIS STILL LOOKS LIKE IT WILL PRODUCE HEAVY SNOW OVER THE NORTHWEST COUNTIES. DID NOT MAKE SIGNIFICANT CHANGES TO STORM TOTAL SNOWFALL AMOUNTS...BUT DID INCREASE AMOUNTS ENOUGH IN HOWARD COUNTY TO UPGRADE THEM FROM ADVISORY TO WINTER STORM WARNING. ALSO ADDED MADISON COUNTY TO THE ADVISORY WITH SIMILAR SNOWFALL TOTALS TO THOSE EXPECTED IN THE REST OF THE ADVISORY AREA. EAST OF THERE...STILL NOT CONFIDENT ENOUGH ON TIMING OF CHANGEOVER TO SNOW AND TOTAL AMOUNTS TO EXPAND THERE JUST YET. WIND GUSTS TODAY WILL BE IN THE 30-45 MPH RANGE AND COMBINED WITH HEAVY SNOW BAND THAT CURRENTLY LOOKS TO SET UP OVER PARTS OF ILLINOIS AND NORTHWEST INDIANA HAVE CHANGED WARREN COUNTY OVER TO A BLIZZARD WARNING. ELSEWHERE WAS NOT CONFIDENT ENOUGH OF HEAVY SNOW CONDITIONS FOR LONG ENOUGH TO EXPECT THE NEAR ZERO VISIBILITIES TO LAST FOR HOURS...BUT ALSO WOULD NOT BE SURPRISED TO SEE THEM THERE OFF AND ON FOR A TIME THIS AFTERNOON/EVENING. CHANGEOVER LOOKS A LITTLE FASTER THAN PREVIOUS FORECAST BUT NOT A LOT. STILL BY MIDMORNING OVER THE NORTHWEST...AFTERNOON CENTRAL...AND NOT UNTIL TONIGHT IN THE EAST AND SOUTHEAST. DECENT UPPER FORCING LASTS THROUGH TONIGHT ACROSS THE AREA BUT DEFORMATION ZONE SHEARS SOMEWHAT AND EXPECT MUCH LOWER SNOWFALL RATES THAN THOSE SEEN DURING THE PERIOD OF MAX SNOWFALL/BANDING TODAY IN THE NORTHWEST. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON SNOW POTENTIAL AND WIND GUSTS THURSDAY. MODELS ARE IN RELATIVELY GOOD AGREEMENT AND GENERALLY USED CONSENSUS. FOR SNOW POPS ON THURSDAY DID INCREASE FROM GUIDANCE. STILL SEE A SHORTWAVE SPOKE ON THE BACK SIDE OF THE SYSTEM THAT SWINGS THROUGH THE TROUGH TO PROVIDE SOME FORCING. SNOW SQUALL PARAMETER JUMPS UP DURING THIS TIME DUE TO SHARP LAPSE RATES SO COMBINED WITH THE FORCING EXPECT TO SEE SNOW SHOWERS DEVELOP. CONTINUED TIGHT PRESSURE GRADIENT ACROSS THE AREA WILL PRODUCE WIND GUSTS IN THE 30-40 MPH RANGE UNTIL EVENING WHEN THE GRADIENT FINALLY SLACKENS AND COMBINING THIS WITH SNOW EXPECT TO SEE SPOTS WHERE VISIBILITIES DROP DRASTICALLY FOR SHORT PERIODS OF TIME. MAY HAVE TO WIND UP EXPANDING ADVISORY BOTH EASTWARD AND IN TIME DEPENDING ON HOW SYSTEM PLAYS OUT...BUT WITH CONFIDENCE NOT AT SLAM DUNK LEVELS AND STILL 24+ HOURS OUT WILL LET NEXT SHIFT HAVE A LOOK AT LATEST GUIDANCE AND GO FROM THERE. MODELS ARE IN AGREEMENT ON DRY WEATHER THURSDAY NIGHT ON...WITH THE EXCEPTION OF A SLIGHT CHANCE FOR SNOW IN THE FAR NORTHEAST EARLY THURSDAY NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... ISSUED AT 330 AM EST WED FEB 24 2016 QUIETER WEATHER WILL BE THE RULE THIS WEEKEND AS THE UPPER FLOW BECOMES MORE ZONAL AND HIGH PRESSURE MOVES EAST ACROSS THE LOWER AND MIDDLE MISSISSIPPI VALLEY INTO THE SOUTHEASTERN U.S. MODELS MOVE AN AREA OF LOW PRESSURE EAST ACROSS THE SOUTHERN GREAT LAKES AND PULL A WEAK COLD FRONT THROUGH OUR REGION AROUND SUNDAY NIGHT. WILL CONTINUE LOW CHANCE POPS LATE SUNDAY THROUGH SUNDAY NIGHT. MOST MODELS INDICATE PRECIP WILL BE DONE AFTER 12Z MONDAY. WILL KEEP SLIGHT CHANCE POPS IN THE NORTH MONDAY NIGHT...BUT OVERALL MODEL TRENDS ARE DRIER UNTIL TUESDAY. ANOTHER SYSTEM WILL BE MOVING OUR WAY THE END OF DAY 7 AND THUS CONTINUE LOW CHANCES OF MAINLY RAIN. IN REGARDS TO TEMPERATURES STAYED CLOSE TO MODEL INITIALIZATION. && .AVIATION /DISCUSSION FOR THE 241500Z TAF UPDATE/... ISSUED AT 1002 AM EST WED FEB 24 2016 MINOR ADJUSTMENTS TO THE TERMINALS BASED ON CURRENT OBS. TRANSITIONED KLAF TO ALL SNOW AND INTRODUCED A RA/SN MIX AT KHUF. POSSIBLE THAT SNOW WILL BEGIN TO MIX IN A TOUCH FASTER THIS AFTERNOON AT KIND AND HIGHLIGHTED AS WELL. 12Z DISCUSSION FOLLOWS. VERY POOR FLYING CONDITIONS WILL BE THE RULE WITH IFR CEILINGS RAIN AND GUSTY WINDS. KLAF MAY START OUT AS MVFR FOR THE FIRST HOUR OR TWO AND THEN IFR OR LIFR AFTER THAT AS PRECIPITATION CHANGES TO SNOW. ELSEWHERE CHANGE OVER WILL OCCUR BY EARLY AFTERNOON KHUF AND CLOSER TO 22Z AT KIND AND KBMG. STRONG LOW PRESSURE OVER WESTERN KENTUCKY WILL TRACK ACROSS EXTREME SOUTHEAST INDIANA BY 18Z AND TO NORTHERN OHIO BY 00Z AND ACROSS THE EASTERN GREAT LAKES TONIGHT. COLDER AIR WILL BE DRAWN INTO OUR REGION THIS AFTERNOON CAUSING RAIN TO CHANGE OVER TO SNOW. MODERATE TO HEAVY SNOW POSSIBLE AT TIMES AT KLAF... OTHERWISE LIGHTER SNOW WILL BE THE RULE MOST OTHER SITES. MODELS INDICATE SNOW WILL LIGHTEN ALL AREAS SOME TONIGHT. THIS WILL RESULT IN VISIBILITIES IMPROVING TO 3 MILES MOST AREAS BY LATE EVENING. NORTH TO NORTHEAST WINDS UP TO 20 KNOTS WITH GUSTS AS HIGH AS 30 KNOTS AT KLAF WITH LESSER GUSTS AT THE OTHER SITES. WINDS MAY DROP TO 10 TO 15 KNOTS AT KBMG MIDDAY AS SURFACE LOW PASSES BY. WINDS WILL BECOME NORTHWEST ALL AREAS THIS AFTERNOON. && .IND WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 1 PM EST THURSDAY FOR INZ037>042- 045>049-051>054-060-061-067. WINTER STORM WARNING UNTIL 1 PM EST THURSDAY FOR INZ021-029>031- 035-036-043-044. BLIZZARD WARNING UNTIL 1 AM EST THURSDAY FOR INZ028. && $$ SYNOPSIS...CP NEAR TERM...MRD/CP SHORT TERM...CP LONG TERM...JH AVIATION...JH/RYAN
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1038 AM EST WED FEB 24 2016 .SYNOPSIS... ISSUED AT 1020 AM EST WED FEB 24 2016 STRONG LOW PRESSURE WILL LIFT UP ACROSS THE OHIO VALLEY TODAY...SPREADING PRECIPITATION NORTH ACROSS THE AREA THROUGH MID MORNING. HEAVY SNOW IS EXPECTED ACROSS NORTHEAST ILLINOIS...NORTHWEST INDIANA AND SOUTHWEST LOWER MICHIGAN. A MIX OF PRECIPITATION IS EXPECTED ELSEWHERE TODAY OVER CENTRAL AND EASTERN INDIANA WITH MAINLY RAIN OVER NORTHWEST OHIO. RAIN WILL TRANSITION BACK TO SNOW THIS AFTERNOON AND EVENING FROM WEST TO EAST. MULTIPLE WINTER WEATHER HEADLINES ARE IN EFFECT ACROSS THE REGION FOR TODAY THROUGH THURSDAY. TRAVEL WILL BE DIFFICULT AT TIMES ESPECIALLY OVER NORTHEAST ILLINOIS AND NORTHWEST INDIANA WITH BLIZZARD CONDITIONS LIKELY. && .UPDATE... ISSUED AT 1020 AM EST WED FEB 24 2016 NO SIGNIFICANT CHANGES EXPECTED TO FORECAST AT THIS TIME. WINDS HAVE BEEN PICKING UP THIS MORNING WITH GUSTS TO BETWEEN 30 AND 40 MPH. KFWA ACTUALLY HAD A GUST TO 45 MPH. VISIBILITIES HAVE NOT BEEN REDUCED MUCH BELOW ONE HALF MILE YET AND THIS IS A CONCERN. STILL EXPECTING HEAVIEST SNOW TO ROTATE INTO NW AREAS THIS AFTERNOON WHILE STRONG PRESSURE GRADIENT PROVIDES INCREASE IN SUSTAINED WIND AND GUSTS. HAND ANALYSIS OF 15Z SFC MAP SHOWS SFC LOW JUST WEST OF KSDF WITH AN ELONGATED AXIS OF LOW PRESSURE STRETCHING NORTHEAST ALONG OH RIVER. BEST PRESSURE FALLS NEAR CLE WHICH SUPPORTS LATEST NAM AND MANY OF THE HIRES GUIDANCE OUTPUT. MAIN CONCERN RIGHT NOW REMAINS ALONG SHARP TRANSITION ZONE BETWEEN RAIN AND SNOW OVER CENTRAL FORECAST AREA. WARNING SEEMS TO HAVE THIS HANDLED WELL FOR NOW WITH ONLY QUESTION BEING IN THE NORTHEAST. LATEST NAM12 SUGGEST PCPN IN WILLIAMS COUNTY MAY REMAIN ALL SNOW WITH RAIN SOUTH OF THERE THIS AFTERNOON. REGIONAL RADAR MOSAIC SHOWING DRY SLOT WORKING NORTH AND HAVING AN IMPACT ON PCPN AND RADAR RETURNS WITH DIMINISHING TRENDS. THIS SHOULD HELP LIMIT AMOUNTS WHERE NO HEADLINES IN EFFECT AND SNOW IS FALLING. THUS PLAN TO KEEP WILLIAMS IN AN ADVISORY BUT WILL BE MONITORING THIS AREA CLOSELY. SOME SLEET REPORTS BEING RECEIVED MAINLY ALONG BACK EDGE OF MORE SOLID PCPN SHIELD WHERE DRY SLOT POKING IN. SEEING SOME ADDITIONAL EVAP COOLING IN LOW LEVELS AND LIKELY ALLOWING FOR SOME REFREEZING BEFORE REACHING GROUND. WILL BE MONITORING LATEST 12Z DATA CLOSELY FOR ANY ADDITIONAL CHANGES TO HEADLINES LATER THIS AFTERNOON. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 545 AM EST WED FEB 24 2016 INTENSE SW OVR THE MID MS VALLEY W/ATTENDANT 990MB SFC REFLECTION OVR NW TN DEEPENING RAPIDLY ERLY THIS MORNING. BROAD ARC OF 6MB/3HR PRES FALLS INTO SRN IN/SW OH WITHIN FOCUSED INTENSE WAA ZONE SPURNING WIDESPREAD MOD-HVY RAIN FM ERN IN IN SWD INTO NRN KY. TIGHT/COHERENT NR TERM HIGHRES GUIDANCE SPOT ON W/NWD REACH OF CURRENT PRECIP SHIELD AND PLACEMENT OF SFC LOW...FURTHER ACCENTUATED BY TRENDS FM RAP GUIDANCE SINCE 00Z...SUGGEST FEW CHGS WARRANTED TO EXISTING HEADLINES ALTHOUGH WILL ADD STEUBEN AND HILLSDALE TO CURRENT WARNING HEADLINE AND IN COORDINATION W/ILX/IND/LOT UPGRADE NW IN ZONES TO BZW. SFC LOW OVR NW TN WILL RAPIDLY LIFT NEWD TDA...REACHING NR KCLE BY 00Z AS TROUGH ALOFT TURNS NEGATIVELY TILTED. THIS WILL PROLONG BOTH STG GRADIENT WINDS AND MOD-HVY SNOW ACRS NW HALF. HWVR EWD WRAP OF SUBTROPICAL JET THROUGH ERN OH AND WWD PLACEMENT OF COUPLING W/NRN JET ACRS THE UPR LAKES SUGGESTS SOME DRY SLOTTING AND EVEN SOME LIMITED POTENTIAL FOR THUNDER ACRS WRN OH THIS AFTERNOON. OTRWS COUPLED JET WILL DRIVE INTENSE/DEEP VERTICAL MOTION ESP FM MID MORNING THROUGH LT AFTN NW HALF W/SHARP EWD SNOW CUTOFF TO NOTHING XPCD AS GENERAL STEADYSTATE RAIN/SNOW LINE STRETCHES FM LOGANSPORT- WARSAW-COLDWATER LINE. IT SHLD BE NOTED HWVR THAT RUC CONTS TO TREND A BIT EWD OF THIS LINE AND IN CONCERT W/AGREEABLE NOD FM 06Z NAM WILL SHIFT A BIT EAST. THAT SAID...BLIZZARD CONDS LIKELY NW ZONES COLLOCATED WITHIN INTENSE DEFORMATION SNOW BAND AND MOST INTENSE GRADIENT FLW. XPC SNOWFALL RATES OF 1-2"/HR LIKELY HERE MID MORNING THROUGH LT AFTN. SECONDARY CONCERN LIES W/EWD PULLOUT OF INTENSE SFC CYCLONE OVERNIGHT AND WRN BOUND OF LK ENHANCING MID LVL MSTR PLUME. FLW SLW TO RELAX AND BLIZZARD WARNING COULD BE EXTENDED PENDING HOW THINGS SHAKE OUT TDA AS SOME SIG ACCUMULATION POTENTIAL EXISTS OVR FAR NW ZONES YET DIMINISHES QUICKLY W/INLAND EXTENT. OTRWS STG GRADIENT FLW REMAINS W/RISE COUPLET SLW TO LIFT OUT THROUGH OH OVERNIGHT WHICH SHLD YIELD CONTD AREAS OF BLOWING SNOW. LK ENHANCEMENT SPREADS FURTHER INLAND THU AM AS LL FLW TURNS NWRLY AND XPC MOST AREAS WILL SEE A GENERAL 1-3 INCH ADDNL ACCUM W/CONTD GUSTY NW WINDS NOT DIMINISHING UNTIL AFTN. && .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 545 AM EST WED FEB 24 2016 REST OF THE PERIOD FAIRLY UNEVENTFUL. CHANCE FOR A FEW LAKE EFFECT SNOW SHOWERS THURSDAY NIGHT INTO FRIDAY AS 850MB TEMPS DROP TO AROUND -13C. HOWEVER...FORECAST SOUNDINGS SHOW INVERSION HEIGHTS ARE PRETTY LOW (AROUND 4 KFT) WITH A FAIR AMOUNT OF DRY AIR ENTRAINMENT. 0-2KM DELTA THETA-E VALUES REMAIN ABOVE ZERO AND PERSISTENT NORTHWEST GRADIENT WILL PREVENT ANY TYPE OF BAND ORGANIZATION. DID RAISE POPS JUST A LITTLE FOR LATE THURSDAY NIGHT/FRIDAY MORNING BUT DONT EXPECT MUCH ACCUMULATION...A HALF INCH AT BEST. ANY RESIDUAL LAKE EFFECT SNOW SHOWERS WILL END BY FRIDAY AFTERNOON AS FLOW BACKS WEST AND EVENTUALLY SOUTHWEST. WILL STILL BE A FAIRLY CHILLY DAY THOUGH WITH MOSTLY CLOUDY SKIES AND HIGHS AT OR BELOW FREEZING. AFTER A FAIRLY PLEASANT SATURDAY...NEXT CHANCE OF PRECIP ARRIVES LATE SUNDAY. PRETTY HEALTHY SHORTWAVE SET TO SWING THROUGH THE REGION WITH UPPER JET SUPPORT AND GOOD PV ADVECTION BUT EXACT TRACK REMAINS UNCERTAIN. DOES APPEAR TO BE VERY WARM AHEAD OF THE FRONT WITH TEMPS POTENTIALLY WELL INTO THE 50S ON SUNDAY...SUPPORTING RAIN AS PTYPE IF ANYTHING OCCURS. THERE IS A CHANCE FOR A QUICK SHOT OF LIGHT SNOW IN OUR NORTHERN COUNTIES SUNDAY NIGHT IF POSTFRONTAL DEFORMATION BAND SWINGS THROUGH THE AREA BUT THAT IS QUESTIONABLE AT THIS POINT...AS ARE THERMAL PROFILES. REGARDLESS...ANY SNOW THAT DOES FALL SHOULD BE LIGHT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 642 AM EST WED FEB 24 2016 RAPID DOWNHILL IN FLIGHT CONDS HAS COMMENCED W/ARRIVAL OF PCPN SHIELD W/IFR OCCASIONAL LIFR CONDS THROUGH THE PD. DIABATIC COOLING WINNING OUT ATTM INVOF KFWA W/FZRA NOTED. CONCURRENT TRENDS IN RAP ALG W/06Z NAM QUITE DISCONCERTING W/EWD SHIFT OF RAIN/SNOW LINE AND LOOKS LIKE A FUNCTION OF BOTH DIABATIC/ADIABATIC PROCESSES GOING ON IN BNDRY LYR THERMAL FIELDS OF WHICH LOOK OVER ESTIMATED IN 00Z GUIDANCE SUITE AS DENOTED IN RAPIDLY DWINDLING MELTING LYR PER DUAL POL DATA. WILL MAKE SOME GRADUATED CHGS TO KFWA TERMINAL. OTRWS PRIOR KSBN FCST LOOKS SOLID W/NR BLIZZARD CONDS LIKELY LT THIS AFTN AND EVENING. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR INZ005>008-016- 017-022>024. WINTER STORM WARNING FROM 10 PM EST /9 PM CST/ THIS EVENING TO 4 PM EST /3 PM CST/ THURSDAY FOR INZ003-004-012>015-020. BLIZZARD WARNING UNTIL 10 PM EST /9 PM CST/ THIS EVENING FOR INZ003-004-012>015-020. WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR INZ009. WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 4 PM EST THURSDAY FOR INZ018-025-032. MI...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR MIZ077>081. OH...WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR OHZ001. LM...STORM WARNING UNTIL 7 AM EST THURSDAY FOR LMZ043-046. && $$ UPDATE...LASHLEY SYNOPSIS...LOTHAMER SHORT TERM...T LONG TERM...AGD AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1002 AM EST WED FEB 24 2016 .UPDATE... AVIATION SECTIONS HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 409 AM EST WED FEB 24 2016 RAIN CHANGES TO WINTER STORM CONDITIONS ACROSS MUCH OF CENTRAL INDIANA TODAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE OHIO VALLEY. STRONG WIND GUSTS AROUND 30-45 MPH ARE EXPECTED TO LAST FROM NOW THROUGH MUCH OF THE DAY ON THURSDAY. AFTER SOME HEAVY SNOW OVER PARTS OF THE AREA TODAY AND TONIGHT COULD SEE SOME SNOW SHOWERS WITH SQUALLS THURSDAY BEFORE THE SYSTEM FINALLY MOVES OUT AND DRY WEATHER REPLACES IT. MUCH WARMER FOR THE WEEKEND THEN SOME SMALLER RAIN OR RAIN SNOW MIX CHANCES OFF AND ON SUNDAY THROUGH TUESDAY. && .NEAR TERM /TODAY AND TONIGHT/... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON CURRENT STORM. GENERALLY STUCK CLOSE TO A NAM/RAP BLEND EARLY WITH THE HRRR SHOWING SOME STRANGE MOVEMENT TO THE SURFACE LOW AND NAM/RAP BOTH INITIALIZING WELL. FOR TONIGHT LEANED ON CONSENSUS. HAVE ALREADY SEEN SOME REPORTS OF SNOW MIXING IN BUT IT HAS GENERALLY BEEN PRETTY BRIEF WITH THE WARM AIR AND MOISTURE ADVECTING EVER FURTHER NORTHWARD. HAVEN/T SEEN ANY SLEET THUS FAR...AND FORECAST SOUNDINGS LOOK MUCH LESS CONDUCIVE FOR THIS THAN PREVIOUS RUNS. THUS TOOK IT OUT. NOT COMPLETELY RULING IT OUT BUT THINK IF IT HAPPENS WILL BE RELATIVELY BRIEF. STRONG FRONTOGENESIS OVER THE AREA CURRENTLY PRODUCING SOME GOOD RAIN ACROSS THE AREA. THIS MOVES NORTH AND COULD SEE MORE SPOTTY COVERAGE FOR A FEW HOURS THIS MORNING BEFORE MORE SIGNIFICANT UPPER FORCING KICKS IN. ALSO DEFORMATION ZONE SHOULD SET UP AND THIS STILL LOOKS LIKE IT WILL PRODUCE HEAVY SNOW OVER THE NORTHWEST COUNTIES. DID NOT MAKE SIGNIFICANT CHANGES TO STORM TOTAL SNOWFALL AMOUNTS...BUT DID INCREASE AMOUNTS ENOUGH IN HOWARD COUNTY TO UPGRADE THEM FROM ADVISORY TO WINTER STORM WARNING. ALSO ADDED MADISON COUNTY TO THE ADVISORY WITH SIMILAR SNOWFALL TOTALS TO THOSE EXPECTED IN THE REST OF THE ADVISORY AREA. EAST OF THERE...STILL NOT CONFIDENT ENOUGH ON TIMING OF CHANGEOVER TO SNOW AND TOTAL AMOUNTS TO EXPAND THERE JUST YET. WIND GUSTS TODAY WILL BE IN THE 30-45 MPH RANGE AND COMBINED WITH HEAVY SNOW BAND THAT CURRENTLY LOOKS TO SET UP OVER PARTS OF ILLINOIS AND NORTHWEST INDIANA HAVE CHANGED WARREN COUNTY OVER TO A BLIZZARD WARNING. ELSEWHERE WAS NOT CONFIDENT ENOUGH OF HEAVY SNOW CONDITIONS FOR LONG ENOUGH TO EXPECT THE NEAR ZERO VISIBILITIES TO LAST FOR HOURS...BUT ALSO WOULD NOT BE SURPRISED TO SEE THEM THERE OFF AND ON FOR A TIME THIS AFTERNOON/EVENING. CHANGEOVER LOOKS A LITTLE FASTER THAN PREVIOUS FORECAST BUT NOT A LOT. STILL BY MIDMORNING OVER THE NORTHWEST...AFTERNOON CENTRAL...AND NOT UNTIL TONIGHT IN THE EAST AND SOUTHEAST. DECENT UPPER FORCING LASTS THROUGH TONIGHT ACROSS THE AREA BUT DEFORMATION ZONE SHEARS SOMEWHAT AND EXPECT MUCH LOWER SNOWFALL RATES THAN THOSE SEEN DURING THE PERIOD OF MAX SNOWFALL/BANDING TODAY IN THE NORTHWEST. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON SNOW POTENTIAL AND WIND GUSTS THURSDAY. MODELS ARE IN RELATIVELY GOOD AGREEMENT AND GENERALLY USED CONSENSUS. FOR SNOW POPS ON THURSDAY DID INCREASE FROM GUIDANCE. STILL SEE A SHORTWAVE SPOKE ON THE BACK SIDE OF THE SYSTEM THAT SWINGS THROUGH THE TROUGH TO PROVIDE SOME FORCING. SNOW SQUALL PARAMETER JUMPS UP DURING THIS TIME DUE TO SHARP LAPSE RATES SO COMBINED WITH THE FORCING EXPECT TO SEE SNOW SHOWERS DEVELOP. CONTINUED TIGHT PRESSURE GRADIENT ACROSS THE AREA WILL PRODUCE WIND GUSTS IN THE 30-40 MPH RANGE UNTIL EVENING WHEN THE GRADIENT FINALLY SLACKENS AND COMBINING THIS WITH SNOW EXPECT TO SEE SPOTS WHERE VISIBILITIES DROP DRASTICALLY FOR SHORT PERIODS OF TIME. MAY HAVE TO WIND UP EXPANDING ADVISORY BOTH EASTWARD AND IN TIME DEPENDING ON HOW SYSTEM PLAYS OUT...BUT WITH CONFIDENCE NOT AT SLAM DUNK LEVELS AND STILL 24+ HOURS OUT WILL LET NEXT SHIFT HAVE A LOOK AT LATEST GUIDANCE AND GO FROM THERE. MODELS ARE IN AGREEMENT ON DRY WEATHER THURSDAY NIGHT ON...WITH THE EXCEPTION OF A SLIGHT CHANCE FOR SNOW IN THE FAR NORTHEAST EARLY THURSDAY NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... ISSUED AT 330 AM EST WED FEB 24 2016 QUIETER WEATHER WILL BE THE RULE THIS WEEKEND AS THE UPPER FLOW BECOMES MORE ZONAL AND HIGH PRESSURE MOVES EAST ACROSS THE LOWER AND MIDDLE MISSISSIPPI VALLEY INTO THE SOUTHEASTERN U.S. MODELS MOVE AN AREA OF LOW PRESSURE EAST ACROSS THE SOUTHERN GREAT LAKES AND PULL A WEAK COLD FRONT THROUGH OUR REGION AROUND SUNDAY NIGHT. WILL CONTINUE LOW CHANCE POPS LATE SUNDAY THROUGH SUNDAY NIGHT. MOST MODELS INDICATE PRECIP WILL BE DONE AFTER 12Z MONDAY. WILL KEEP SLIGHT CHANCE POPS IN THE NORTH MONDAY NIGHT...BUT OVERALL MODEL TRENDS ARE DRIER UNTIL TUESDAY. ANOTHER SYSTEM WILL BE MOVING OUR WAY THE END OF DAY 7 AND THUS CONTINUE LOW CHANCES OF MAINLY RAIN. IN REGARDS TO TEMPERATURES STAYED CLOSE TO MODEL INITIALIZATION. && .AVIATION /DISCUSSION FOR THE 241500Z TAF UPDATE/... ISSUED AT 1002 AM EST WED FEB 24 2016 MINOR ADJUSTMENTS TO THE TERMINALS BASED ON CURRENT OBS. TRANSITIONED KLAF TO ALL SNOW AND INTRODUCED A RA/SN MIX AT KHUF. POSSIBLE THAT SNOW WILL BEGIN TO MIX IN A TOUCH FASTER THIS AFTERNOON AT KIND AND HIGHLIGHTED AS WELL. 12Z DISCUSSION FOLLOWS. VERY POOR FLYING CONDITIONS WILL BE THE RULE WITH IFR CEILINGS RAIN AND GUSTY WINDS. KLAF MAY START OUT AS MVFR FOR THE FIRST HOUR OR TWO AND THEN IFR OR LIFR AFTER THAT AS PRECIPITATION CHANGES TO SNOW. ELSEWHERE CHANGE OVER WILL OCCUR BY EARLY AFTERNOON KHUF AND CLOSER TO 22Z AT KIND AND KBMG. STRONG LOW PRESSURE OVER WESTERN KENTUCKY WILL TRACK ACROSS EXTREME SOUTHEAST INDIANA BY 18Z AND TO NORTHERN OHIO BY 00Z AND ACROSS THE EASTERN GREAT LAKES TONIGHT. COLDER AIR WILL BE DRAWN INTO OUR REGION THIS AFTERNOON CAUSING RAIN TO CHANGE OVER TO SNOW. MODERATE TO HEAVY SNOW POSSIBLE AT TIMES AT KLAF... OTHERWISE LIGHTER SNOW WILL BE THE RULE MOST OTHER SITES. MODELS INDICATE SNOW WILL LIGHTEN ALL AREAS SOME TONIGHT. THIS WILL RESULT IN VISIBILITIES IMPROVING TO 3 MILES MOST AREAS BY LATE EVENING. NORTH TO NORTHEAST WINDS UP TO 20 KNOTS WITH GUSTS AS HIGH AS 30 KNOTS AT KLAF WITH LESSER GUSTS AT THE OTHER SITES. WINDS MAY DROP TO 10 TO 15 KNOTS AT KBMG MIDDAY AS SURFACE LOW PASSES BY. WINDS WILL BECOME NORTHWEST ALL AREAS THIS AFTERNOON. && .IND WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 1 PM EST THURSDAY FOR INZ037>040-045>047-051>054-060-061-067. WINTER STORM WARNING FROM 10 AM THIS MORNING TO 1 PM EST THURSDAY FOR INZ021-029>031-035-036-043-044. BLIZZARD WARNING FROM 10 AM THIS MORNING TO 1 AM EST THURSDAY FOR INZ028. && $$ SYNOPSIS...CP NEAR TERM...CP SHORT TERM...CP LONG TERM...JH AVIATION...JH/RYAN
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
642 AM EST WED FEB 24 2016 .SYNOPSIS... ISSUED AT 545 AM EST WED FEB 24 2016 STRONG LOW PRESSURE WILL LIFT UP ACROSS THE OHIO VALLEY TODAY...SPREADING PRECIPITATION NORTH ACROSS THE AREA THROUGH MID MORNING. HEAVY SNOW IS EXPECTED ACROSS NORTHEAST ILLINOIS...NORTHWEST INDIANA AND SOUTHWEST LOWER MICHIGAN. A MIX OF PRECIPITATION IS EXPECTED ELSEWHERE TODAY OVER CENTRAL AND EASTERN INDIANA WITH MAINLY RAIN OVER NORTHWEST OHIO. RAIN WILL TRANSITION BACK TO SNOW THIS AFTERNOON AND EVENING FROM WEST TO EAST. MULTIPLE WINTER WEATHER HEADLINES ARE IN EFFECT ACROSS THE REGION FOR TODAY THROUGH THURSDAY. TRAVEL WILL BE DIFFICULT AT TIMES ESPECIALLY OVER NORTHEAST ILLINOIS AND NORTHWEST INDIANA WITH BLIZZARD CONDITIONS LIKELY. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 545 AM EST WED FEB 24 2016 INTENSE SW OVR THE MID MS VALLEY W/ATTENDANT 990MB SFC REFLECTION OVR NW TN DEEPENING RAPIDLY ERLY THIS MORNING. BROAD ARC OF 6MB/3HR PRES FALLS INTO SRN IN/SW OH WITHIN FOCUSED INTENSE WAA ZONE SPURNING WIDESPREAD MOD-HVY RAIN FM ERN IN IN SWD INTO NRN KY. TIGHT/COHERENT NR TERM HIGHRES GUIDANCE SPOT ON W/NWD REACH OF CURRENT PRECIP SHIELD AND PLACEMENT OF SFC LOW...FURTHER ACCENTUATED BY TRENDS FM RAP GUIDANCE SINCE 00Z...SUGGEST FEW CHGS WARRANTED TO EXISTING HEADLINES ALTHOUGH WILL ADD STEUBEN AND HILLSDALE TO CURRENT WARNING HEADLINE AND IN COORDINATION W/ILX/IND/LOT UPGRADE NW IN ZONES TO BZW. SFC LOW OVR NW TN WILL RAPIDLY LIFT NEWD TDA...REACHING NR KCLE BY 00Z AS TROUGH ALOFT TURNS NEGATIVELY TILTED. THIS WILL PROLONG BOTH STG GRADIENT WINDS AND MOD-HVY SNOW ACRS NW HALF. HWVR EWD WRAP OF SUBTROPICAL JET THROUGH ERN OH AND WWD PLACEMENT OF COUPLING W/NRN JET ACRS THE UPR LAKES SUGGESTS SOME DRY SLOTTING AND EVEN SOME LIMITED POTENTIAL FOR THUNDER ACRS WRN OH THIS AFTERNOON. OTRWS COUPLED JET WILL DRIVE INTENSE/DEEP VERTICAL MOTION ESP FM MID MORNING THROUGH LT AFTN NW HALF W/SHARP EWD SNOW CUTOFF TO NOTHING XPCD AS GENERAL STEADYSTATE RAIN/SNOW LINE STRETCHES FM LOGANSPORT- WARSAW-COLDWATER LINE. IT SHLD BE NOTED HWVR THAT RUC CONTS TO TREND A BIT EWD OF THIS LINE AND IN CONCERT W/AGREEABLE NOD FM 06Z NAM WILL SHIFT A BIT EAST. THAT SAID...BLIZZARD CONDS LIKELY NW ZONES COLLOCATED WITHIN INTENSE DEFORMATION SNOW BAND AND MOST INTENSE GRADIENT FLW. XPC SNOWFALL RATES OF 1-2"/HR LIKELY HERE MID MORNING THROUGH LT AFTN. SECONDARY CONCERN LIES W/EWD PULLOUT OF INTENSE SFC CYCLONE OVERNIGHT AND WRN BOUND OF LK ENHANCING MID LVL MSTR PLUME. FLW SLW TO RELAX AND BLIZZARD WARNING COULD BE EXTENDED PENDING HOW THINGS SHAKE OUT TDA AS SOME SIG ACCUMULATION POTENTIAL EXISTS OVR FAR NW ZONES YET DIMINISHES QUICKLY W/INLAND EXTENT. OTRWS STG GRADIENT FLW REMAINS W/RISE COUPLET SLW TO LIFT OUT THROUGH OH OVERNIGHT WHICH SHLD YIELD CONTD AREAS OF BLOWING SNOW. LK ENHANCEMENT SPREADS FURTHER INLAND THU AM AS LL FLW TURNS NWRLY AND XPC MOST AREAS WILL SEE A GENERAL 1-3 INCH ADDNL ACCUM W/CONTD GUSTY NW WINDS NOT DIMINISHING UNTIL AFTN. && .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 545 AM EST WED FEB 24 2016 REST OF THE PERIOD FAIRLY UNEVENTFUL. CHANCE FOR A FEW LAKE EFFECT SNOW SHOWERS THURSDAY NIGHT INTO FRIDAY AS 850MB TEMPS DROP TO AROUND -13C. HOWEVER...FORECAST SOUNDINGS SHOW INVERSION HEIGHTS ARE PRETTY LOW (AROUND 4 KFT) WITH A FAIR AMOUNT OF DRY AIR ENTRAINMENT. 0-2KM DELTA THETA-E VALUES REMAIN ABOVE ZERO AND PERSISTENT NORTHWEST GRADIENT WILL PREVENT ANY TYPE OF BAND ORGANIZATION. DID RAISE POPS JUST A LITTLE FOR LATE THURSDAY NIGHT/FRIDAY MORNING BUT DONT EXPECT MUCH ACCUMULATION...A HALF INCH AT BEST. ANY RESIDUAL LAKE EFFECT SNOW SHOWERS WILL END BY FRIDAY AFTERNOON AS FLOW BACKS WEST AND EVENTUALLY SOUTHWEST. WILL STILL BE A FAIRLY CHILLY DAY THOUGH WITH MOSTLY CLOUDY SKIES AND HIGHS AT OR BELOW FREEZING. AFTER A FAIRLY PLEASANT SATURDAY...NEXT CHANCE OF PRECIP ARRIVES LATE SUNDAY. PRETTY HEALTHY SHORTWAVE SET TO SWING THROUGH THE REGION WITH UPPER JET SUPPORT AND GOOD PV ADVECTION BUT EXACT TRACK REMAINS UNCERTAIN. DOES APPEAR TO BE VERY WARM AHEAD OF THE FRONT WITH TEMPS POTENTIALLY WELL INTO THE 50S ON SUNDAY...SUPPORTING RAIN AS PTYPE IF ANYTHING OCCURS. THERE IS A CHANCE FOR A QUICK SHOT OF LIGHT SNOW IN OUR NORTHERN COUNTIES SUNDAY NIGHT IF POSTFRONTAL DEFORMATION BAND SWINGS THROUGH THE AREA BUT THAT IS QUESTIONABLE AT THIS POINT...AS ARE THERMAL PROFILES. REGARDLESS...ANY SNOW THAT DOES FALL SHOULD BE LIGHT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 642 AM EST WED FEB 24 2016 RAPID DOWNHILL IN FLIGHT CONDS HAS COMMENCED W/ARRIVAL OF PCPN SHIELD W/IFR OCCASIONAL LIFR CONDS THROUGH THE PD. DIABATIC COOLING WINNING OUT ATTM INVOF KFWA W/FZRA NOTED. CONCURRENT TRENDS IN RAP ALG W/06Z NAM QUITE DISCONCERTING W/EWD SHIFT OF RAIN/SNOW LINE AND LOOKS LIKE A FUNCTION OF BOTH DIABATIC/ADIABATIC PROCESSES GOING ON IN BNDRY LYR THERMAL FIELDS OF WHICH LOOK OVER ESTIMATED IN 00Z GUIDANCE SUITE AS DENOTED IN RAPIDLY DWINDLING MELTING LYR PER DUAL POL DATA. WILL MAKE SOME GRADUATED CHGS TO KFWA TERMINAL. OTRWS PRIOR KSBN FCST LOOKS SOLID W/NR BLIZZARD CONDS LIKELY LT THIS AFTN AND EVENING. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR INZ005>008-016- 017-022>024. WINTER STORM WARNING FROM 10 PM EST /9 PM CST/ THIS EVENING TO 4 PM EST /3 PM CST/ THURSDAY FOR INZ003-004-012>015-020. BLIZZARD WARNING UNTIL 10 PM EST /9 PM CST/ THIS EVENING FOR INZ003-004-012>015-020. WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 PM EST THURSDAY FOR INZ009. WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 4 PM EST THURSDAY FOR INZ018-025-032. MI...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR MIZ077>081. OH...WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 PM EST THURSDAY FOR OHZ001. LM...STORM WARNING FROM 1 PM THIS AFTERNOON TO 7 AM EST THURSDAY FOR LMZ043-046. && $$ SYNOPSIS...LOTHAMER SHORT TERM...T LONG TERM...AGD AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
600 AM EST WED FEB 24 2016 .UPDATE... AVIATION SECTIONS HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 409 AM EST WED FEB 24 2016 RAIN CHANGES TO WINTER STORM CONDITIONS ACROSS MUCH OF CENTRAL INDIANA TODAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE OHIO VALLEY. STRONG WIND GUSTS AROUND 30-45 MPH ARE EXPECTED TO LAST FROM NOW THROUGH MUCH OF THE DAY ON THURSDAY. AFTER SOME HEAVY SNOW OVER PARTS OF THE AREA TODAY AND TONIGHT COULD SEE SOME SNOW SHOWERS WITH SQUALLS THURSDAY BEFORE THE SYSTEM FINALLY MOVES OUT AND DRY WEATHER REPLACES IT. MUCH WARMER FOR THE WEEKEND THEN SOME SMALLER RAIN OR RAIN SNOW MIX CHANCES OFF AND ON SUNDAY THROUGH TUESDAY. && .NEAR TERM /TODAY AND TONIGHT/... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON CURRENT STORM. GENERALLY STUCK CLOSE TO A NAM/RAP BLEND EARLY WITH THE HRRR SHOWING SOME STRANGE MOVEMENT TO THE SURFACE LOW AND NAM/RAP BOTH INITIALIZING WELL. FOR TONIGHT LEANED ON CONSENSUS. HAVE ALREADY SEEN SOME REPORTS OF SNOW MIXING IN BUT IT HAS GENERALLY BEEN PRETTY BRIEF WITH THE WARM AIR AND MOISTURE ADVECTING EVER FURTHER NORTHWARD. HAVEN/T SEEN ANY SLEET THUS FAR...AND FORECAST SOUNDINGS LOOK MUCH LESS CONDUCIVE FOR THIS THAN PREVIOUS RUNS. THUS TOOK IT OUT. NOT COMPLETELY RULING IT OUT BUT THINK IF IT HAPPENS WILL BE RELATIVELY BRIEF. STRONG FRONTOGENESIS OVER THE AREA CURRENTLY PRODUCING SOME GOOD RAIN ACROSS THE AREA. THIS MOVES NORTH AND COULD SEE MORE SPOTTY COVERAGE FOR A FEW HOURS THIS MORNING BEFORE MORE SIGNIFICANT UPPER FORCING KICKS IN. ALSO DEFORMATION ZONE SHOULD SET UP AND THIS STILL LOOKS LIKE IT WILL PRODUCE HEAVY SNOW OVER THE NORTHWEST COUNTIES. DID NOT MAKE SIGNIFICANT CHANGES TO STORM TOTAL SNOWFALL AMOUNTS...BUT DID INCREASE AMOUNTS ENOUGH IN HOWARD COUNTY TO UPGRADE THEM FROM ADVISORY TO WINTER STORM WARNING. ALSO ADDED MADISON COUNTY TO THE ADVISORY WITH SIMILAR SNOWFALL TOTALS TO THOSE EXPECTED IN THE REST OF THE ADVISORY AREA. EAST OF THERE...STILL NOT CONFIDENT ENOUGH ON TIMING OF CHANGEOVER TO SNOW AND TOTAL AMOUNTS TO EXPAND THERE JUST YET. WIND GUSTS TODAY WILL BE IN THE 30-45 MPH RANGE AND COMBINED WITH HEAVY SNOW BAND THAT CURRENTLY LOOKS TO SET UP OVER PARTS OF ILLINOIS AND NORTHWEST INDIANA HAVE CHANGED WARREN COUNTY OVER TO A BLIZZARD WARNING. ELSEWHERE WAS NOT CONFIDENT ENOUGH OF HEAVY SNOW CONDITIONS FOR LONG ENOUGH TO EXPECT THE NEAR ZERO VISIBILITIES TO LAST FOR HOURS...BUT ALSO WOULD NOT BE SURPRISED TO SEE THEM THERE OFF AND ON FOR A TIME THIS AFTERNOON/EVENING. CHANGEOVER LOOKS A LITTLE FASTER THAN PREVIOUS FORECAST BUT NOT A LOT. STILL BY MIDMORNING OVER THE NORTHWEST...AFTERNOON CENTRAL...AND NOT UNTIL TONIGHT IN THE EAST AND SOUTHEAST. DECENT UPPER FORCING LASTS THROUGH TONIGHT ACROSS THE AREA BUT DEFORMATION ZONE SHEARS SOMEWHAT AND EXPECT MUCH LOWER SNOWFALL RATES THAN THOSE SEEN DURING THE PERIOD OF MAX SNOWFALL/BANDING TODAY IN THE NORTHWEST. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON SNOW POTENTIAL AND WIND GUSTS THURSDAY. MODELS ARE IN RELATIVELY GOOD AGREEMENT AND GENERALLY USED CONSENSUS. FOR SNOW POPS ON THURSDAY DID INCREASE FROM GUIDANCE. STILL SEE A SHORTWAVE SPOKE ON THE BACK SIDE OF THE SYSTEM THAT SWINGS THROUGH THE TROUGH TO PROVIDE SOME FORCING. SNOW SQUALL PARAMETER JUMPS UP DURING THIS TIME DUE TO SHARP LAPSE RATES SO COMBINED WITH THE FORCING EXPECT TO SEE SNOW SHOWERS DEVELOP. CONTINUED TIGHT PRESSURE GRADIENT ACROSS THE AREA WILL PRODUCE WIND GUSTS IN THE 30-40 MPH RANGE UNTIL EVENING WHEN THE GRADIENT FINALLY SLACKENS AND COMBINING THIS WITH SNOW EXPECT TO SEE SPOTS WHERE VISIBILITIES DROP DRASTICALLY FOR SHORT PERIODS OF TIME. MAY HAVE TO WIND UP EXPANDING ADVISORY BOTH EASTWARD AND IN TIME DEPENDING ON HOW SYSTEM PLAYS OUT...BUT WITH CONFIDENCE NOT AT SLAM DUNK LEVELS AND STILL 24+ HOURS OUT WILL LET NEXT SHIFT HAVE A LOOK AT LATEST GUIDANCE AND GO FROM THERE. MODELS ARE IN AGREEMENT ON DRY WEATHER THURSDAY NIGHT ON...WITH THE EXCEPTION OF A SLIGHT CHANCE FOR SNOW IN THE FAR NORTHEAST EARLY THURSDAY NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... ISSUED AT 330 AM EST WED FEB 24 2016 QUIETER WEATHER WILL BE THE RULE THIS WEEKEND AS THE UPPER FLOW BECOMES MORE ZONAL AND HIGH PRESSURE MOVES EAST ACROSS THE LOWER AND MIDDLE MISSISSIPPI VALLEY INTO THE SOUTHEASTERN U.S. MODELS MOVE AN AREA OF LOW PRESSURE EAST ACROSS THE SOUTHERN GREAT LAKES AND PULL A WEAK COLD FRONT THROUGH OUR REGION AROUND SUNDAY NIGHT. WILL CONTINUE LOW CHANCE POPS LATE SUNDAY THROUGH SUNDAY NIGHT. MOST MODELS INDICATE PRECIP WILL BE DONE AFTER 12Z MONDAY. WILL KEEP SLIGHT CHANCE POPS IN THE NORTH MONDAY NIGHT...BUT OVERALL MODEL TRENDS ARE DRIER UNTIL TUESDAY. ANOTHER SYSTEM WILL BE MOVING OUR WAY THE END OF DAY 7 AND THUS CONTINUE LOW CHANCES OF MAINLY RAIN. IN REGARDS TO TEMPERATURES STAYED CLOSE TO MODEL INITIALIZATION. && .AVIATION /DISCUSSION FOR THE 240900Z TAF ISSUANCE/... ISSUED AT 600 AM EST WED FEB 24 2016 VERY POOR FLYING CONDITIONS WILL BE THE RULE WITH IFR CEILINGS RAIN AND GUSTY WINDS. KLAF MAY START OUT AS MVFR FOR THE FIRST HOUR OR TWO AND THEN IFR OR LIFR AFTER THAT AS PRECIPITATION CHANGES TO SNOW. ELSEWHERE CHANGE OVER WILL OCCUR BY EARLY AFTERNOON KHUF AND CLOSER TO 22Z AT KIND AND KBMG. STRONG LOW PRESSURE OVER WESTERN KENTUCKY WILL TRACK ACROSS EXTREME SOUTHEAST INDIANA BY 18Z AND TO NORTHERN OHIO BY 00Z AND ACROSS THE EASTERN GREAT LAKES TONIGHT. COLDER AIR WILL BE DRAWN INTO OUR REGION THIS AFTERNOON CAUSING RAIN TO CHANGE OVER TO SNOW. MODERATE TO HEAVY SNOW POSSIBLE AT TIMES AT KLAF... OTHERWISE LIGHTER SNOW WILL BE THE RULE MOST OTHER SITES. MODELS INDICATE SNOW WILL LIGHTEN ALL AREAS SOME TONIGHT. THIS WILL RESULT IN VISIBILITIES IMPROVING TO 3 MILES MOST AREAS BY LATE EVENING. NORTH TO NORTHEAST WINDS UP TO 20 KNOTS WITH GUSTS AS HIGH AS 30 KNOTS AT KLAF WITH LESSER GUSTS AT THE OTHER SITES. WINDS MAY DROP TO 10 TO 15 KNOTS AT KBMG MIDDAY AS SURFACE LOW PASSES BY. WINDS WILL BECOME NORTHWEST ALL AREAS THIS AFTERNOON. && .IND WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 1 PM EST THURSDAY FOR INZ037>040-045>047-051>054-060-061-067. WINTER STORM WARNING FROM 10 AM THIS MORNING TO 1 PM EST THURSDAY FOR INZ021-029>031-035-036-043-044. BLIZZARD WARNING FROM 10 AM THIS MORNING TO 1 AM EST THURSDAY FOR INZ028. && $$ SYNOPSIS...CP NEAR TERM...CP SHORT TERM...CP LONG TERM...JH AVIATION...JH
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
547 AM EST WED FEB 24 2016 .SYNOPSIS... ISSUED AT 545 AM EST WED FEB 24 2016 STRONG LOW PRESSURE WILL LIFT UP ACROSS THE OHIO VALLEY TODAY...SPREADING PRECIPITATION NORTH ACROSS THE AREA THROUGH MID MORNING. HEAVY SNOW IS EXPECTED ACROSS NORTHEAST ILLINOIS...NORTHWEST INDIANA AND SOUTHWEST LOWER MICHIGAN. A MIX OF PRECIPITATION IS EXPECTED ELSEWHERE TODAY OVER CENTRAL AND EASTERN INDIANA WITH MAINLY RAIN OVER NORTHWEST OHIO. RAIN WILL TRANSITION BACK TO SNOW THIS AFTERNOON AND EVENING FROM WEST TO EAST. MULTIPLE WINTER WEATHER HEADLINES ARE IN EFFECT ACROSS THE REGION FOR TODAY THROUGH THURSDAY. TRAVEL WILL BE DIFFICULT AT TIMES ESPECIALLY OVER NORTHEAST ILLINOIS AND NORTHWEST INDIANA WITH BLIZZARD CONDITIONS LIKELY. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 545 AM EST WED FEB 24 2016 INTENSE SW OVR THE MID MS VALLEY W/ATTENDANT 990MB SFC REFLECTION OVR NW TN DEEPENING RAPIDLY ERLY THIS MORNING. BROAD ARC OF 6MB/3HR PRES FALLS INTO SRN IN/SW OH WITHIN FOCUSED INTENSE WAA ZONE SPURNING WIDESPREAD MOD-HVY RAIN FM ERN IN IN SWD INTO NRN KY. TIGHT/COHERENT NR TERM HIGHRES GUIDANCE SPOT ON W/NWD REACH OF CURRENT PRECIP SHIELD AND PLACEMENT OF SFC LOW...FURTHER ACCENTUATED BY TRENDS FM RAP GUIDANCE SINCE 00Z...SUGGEST FEW CHGS WARRANTED TO EXISTING HEADLINES ALTHOUGH WILL ADD STEUBEN AND HILLSDALE TO CURRENT WARNING HEADLINE AND IN COORDINATION W/ILX/IND/LOT UPGRADE NW IN ZONES TO BZW. SFC LOW OVR NW TN WILL RAPIDLY LIFT NEWD TDA...REACHING NR KCLE BY 00Z AS TROUGH ALOFT TURNS NEGATIVELY TILTED. THIS WILL PROLONG BOTH STG GRADIENT WINDS AND MOD-HVY SNOW ACRS NW HALF. HWVR EWD WRAP OF SUBTROPICAL JET THROUGH ERN OH AND WWD PLACEMENT OF COUPLING W/NRN JET ACRS THE UPR LAKES SUGGESTS SOME DRY SLOTTING AND EVEN SOME LIMITED POTENTIAL FOR THUNDER ACRS WRN OH THIS AFTERNOON. OTRWS COUPLED JET WILL DRIVE INTENSE/DEEP VERTICAL MOTION ESP FM MID MORNING THROUGH LT AFTN NW HALF W/SHARP EWD SNOW CUTOFF TO NOTHING XPCD AS GENERAL STEADYSTATE RAIN/SNOW LINE STRETCHES FM LOGANSPORT- WARSAW-COLDWATER LINE. IT SHLD BE NOTED HWVR THAT RUC CONTS TO TREND A BIT EWD OF THIS LINE AND IN CONCERT W/AGREEABLE NOD FM 06Z NAM WILL SHIFT A BIT EAST. THAT SAID...BLIZZARD CONDS LIKELY NW ZONES COLLOCATED WITHIN INTENSE DEFORMATION SNOW BAND AND MOST INTENSE GRADIENT FLW. XPC SNOWFALL RATES OF 1-2"/HR LIKELY HERE MID MORNING THROUGH LT AFTN. SECONDARY CONCERN LIES W/EWD PULLOUT OF INTENSE SFC CYCLONE OVERNIGHT AND WRN BOUND OF LK ENHANCING MID LVL MSTR PLUME. FLW SLW TO RELAX AND BLIZZARD WARNING COULD BE EXTENDED PENDING HOW THINGS SHAKE OUT TDA AS SOME SIG ACCUMULATION POTENTIAL EXISTS OVR FAR NW ZONES YET DIMINISHES QUICKLY W/INLAND EXTENT. OTRWS STG GRADIENT FLW REMAINS W/RISE COUPLET SLW TO LIFT OUT THROUGH OH OVERNIGHT WHICH SHLD YIELD CONTD AREAS OF BLOWING SNOW. LK ENHANCEMENT SPREADS FURTHER INLAND THU AM AS LL FLW TURNS NWRLY AND XPC MOST AREAS WILL SEE A GENERAL 1-3 INCH ADDNL ACCUM W/CONTD GUSTY NW WINDS NOT DIMINISHING UNTIL AFTN. && .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 545 AM EST WED FEB 24 2016 REST OF THE PERIOD FAIRLY UNEVENTFUL. CHANCE FOR A FEW LAKE EFFECT SNOW SHOWERS THURSDAY NIGHT INTO FRIDAY AS 850MB TEMPS DROP TO AROUND -13C. HOWEVER...FORECAST SOUNDINGS SHOW INVERSION HEIGHTS ARE PRETTY LOW (AROUND 4 KFT) WITH A FAIR AMOUNT OF DRY AIR ENTRAINMENT. 0-2KM DELTA THETA-E VALUES REMAIN ABOVE ZERO AND PERSISTENT NORTHWEST GRADIENT WILL PREVENT ANY TYPE OF BAND ORGANIZATION. DID RAISE POPS JUST A LITTLE FOR LATE THURSDAY NIGHT/FRIDAY MORNING BUT DONT EXPECT MUCH ACCUMULATION...A HALF INCH AT BEST. ANY RESIDUAL LAKE EFFECT SNOW SHOWERS WILL END BY FRIDAY AFTERNOON AS FLOW BACKS WEST AND EVENTUALLY SOUTHWEST. WILL STILL BE A FAIRLY CHILLY DAY THOUGH WITH MOSTLY CLOUDY SKIES AND HIGHS AT OR BELOW FREEZING. AFTER A FAIRLY PLEASANT SATURDAY...NEXT CHANCE OF PRECIP ARRIVES LATE SUNDAY. PRETTY HEALTHY SHORTWAVE SET TO SWING THROUGH THE REGION WITH UPPER JET SUPPORT AND GOOD PV ADVECTION BUT EXACT TRACK REMAINS UNCERTAIN. DOES APPEAR TO BE VERY WARM AHEAD OF THE FRONT WITH TEMPS POTENTIALLY WELL INTO THE 50S ON SUNDAY...SUPPORTING RAIN AS PTYPE IF ANYTHING OCCURS. THERE IS A CHANCE FOR A QUICK SHOT OF LIGHT SNOW IN OUR NORTHERN COUNTIES SUNDAY NIGHT IF POSTFRONTAL DEFORMATION BAND SWINGS THROUGH THE AREA BUT THAT IS QUESTIONABLE AT THIS POINT...AS ARE THERMAL PROFILES. REGARDLESS...ANY SNOW THAT DOES FALL SHOULD BE LIGHT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1229 AM EST WED FEB 24 2016 RAPID DOWNHILL SLIDE XPCD THROUGH DAYBREAK AS INTENSE LOW PRES OVR WRN KY SHIFTS NEWD TO KTOL BY EVENING. BROAD WAA INDUCED PRECIP SHIELD IS SPREADING QUICKLY NWD AND WILL OVERSPREAD THE TERMINALS 09-12Z AS FLIGHT CONDS LWR TO IFR. RAIN/SNOW LINE XPCD TO LAY OUT INBTWN W/MOD-HVY SNOW AT KSBN VS RAIN AT KFWA THROUGH ABT 00Z. THEREAFTER CHG OVR XPCD AT KFWA. HWVR GREATER WX RELATED IMPACTS XPCD INVOF KSBN W/HVY SNOW AND GRADIENT GUSTS AOA 35KTS THIS AFTN. DEFORMATION INDUCED SNOW...ALBEIT LIGHTER...WILL PERSIST OVR KSBN TERMINAL OVERNIGHT W/STG NW SFC WINDS CONTG. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR INZ005>008-016- 017-022>024. WINTER STORM WARNING FROM 10 PM EST /9 PM CST/ THIS EVENING TO 4 PM EST /3 PM CST/ THURSDAY FOR INZ003-004-012>015-020. BLIZZARD WARNING UNTIL 10 PM EST /9 PM CST/ THIS EVENING FOR INZ003-004-012>015-020. WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 PM EST THURSDAY FOR INZ009. WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 4 PM EST THURSDAY FOR INZ018-025-032. MI...WINTER STORM WARNING UNTIL 4 PM EST THURSDAY FOR MIZ077>081. OH...WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 PM EST THURSDAY FOR OHZ001. LM...STORM WARNING FROM 1 PM THIS AFTERNOON TO 7 AM EST THURSDAY FOR LMZ043-046. && $$ SYNOPSIS...LOTHAMER SHORT TERM...T LONG TERM...AGD AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
442 AM EST WED FEB 24 2016 .UPDATE... THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 409 AM EST WED FEB 24 2016 RAIN CHANGES TO WINTER STORM CONDITIONS ACROSS MUCH OF CENTRAL INDIANA TODAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE OHIO VALLEY. STRONG WIND GUSTS AROUND 30-45 MPH ARE EXPECTED TO LAST FROM NOW THROUGH MUCH OF THE DAY ON THURSDAY. AFTER SOME HEAVY SNOW OVER PARTS OF THE AREA TODAY AND TONIGHT COULD SEE SOME SNOW SHOWERS WITH SQUALLS THURSDAY BEFORE THE SYSTEM FINALLY MOVES OUT AND DRY WEATHER REPLACES IT. MUCH WARMER FOR THE WEEKEND THEN SOME SMALLER RAIN OR RAIN SNOW MIX CHANCES OFF AND ON SUNDAY THROUGH TUESDAY. && .NEAR TERM /TODAY AND TONIGHT/... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON CURRENT STORM. GENERALLY STUCK CLOSE TO A NAM/RAP BLEND EARLY WITH THE HRRR SHOWING SOME STRANGE MOVEMENT TO THE SURFACE LOW AND NAM/RAP BOTH INITIALIZING WELL. FOR TONIGHT LEANED ON CONSENSUS. HAVE ALREADY SEEN SOME REPORTS OF SNOW MIXING IN BUT IT HAS GENERALLY BEEN PRETTY BRIEF WITH THE WARM AIR AND MOISTURE ADVECTING EVER FURTHER NORTHWARD. HAVEN/T SEEN ANY SLEET THUS FAR...AND FORECAST SOUNDINGS LOOK MUCH LESS CONDUCIVE FOR THIS THAN PREVIOUS RUNS. THUS TOOK IT OUT. NOT COMPLETELY RULING IT OUT BUT THINK IF IT HAPPENS WILL BE RELATIVELY BRIEF. STRONG FRONTOGENESIS OVER THE AREA CURRENTLY PRODUCING SOME GOOD RAIN ACROSS THE AREA. THIS MOVES NORTH AND COULD SEE MORE SPOTTY COVERAGE FOR A FEW HOURS THIS MORNING BEFORE MORE SIGNIFICANT UPPER FORCING KICKS IN. ALSO DEFORMATION ZONE SHOULD SET UP AND THIS STILL LOOKS LIKE IT WILL PRODUCE HEAVY SNOW OVER THE NORTHWEST COUNTIES. DID NOT MAKE SIGNIFICANT CHANGES TO STORM TOTAL SNOWFALL AMOUNTS...BUT DID INCREASE AMOUNTS ENOUGH IN HOWARD COUNTY TO UPGRADE THEM FROM ADVISORY TO WINTER STORM WARNING. ALSO ADDED MADISON COUNTY TO THE ADVISORY WITH SIMILAR SNOWFALL TOTALS TO THOSE EXPECTED IN THE REST OF THE ADVISORY AREA. EAST OF THERE...STILL NOT CONFIDENT ENOUGH ON TIMING OF CHANGEOVER TO SNOW AND TOTAL AMOUNTS TO EXPAND THERE JUST YET. WIND GUSTS TODAY WILL BE IN THE 30-45 MPH RANGE AND COMBINED WITH HEAVY SNOW BAND THAT CURRENTLY LOOKS TO SET UP OVER PARTS OF ILLINOIS AND NORTHWEST INDIANA HAVE CHANGED WARREN COUNTY OVER TO A BLIZZARD WARNING. ELSEWHERE WAS NOT CONFIDENT ENOUGH OF HEAVY SNOW CONDITIONS FOR LONG ENOUGH TO EXPECT THE NEAR ZERO VISIBILITIES TO LAST FOR HOURS...BUT ALSO WOULD NOT BE SURPRISED TO SEE THEM THERE OFF AND ON FOR A TIME THIS AFTERNOON/EVENING. CHANGEOVER LOOKS A LITTLE FASTER THAN PREVIOUS FORECAST BUT NOT A LOT. STILL BY MIDMORNING OVER THE NORTHWEST...AFTERNOON CENTRAL...AND NOT UNTIL TONIGHT IN THE EAST AND SOUTHEAST. DECENT UPPER FORCING LASTS THROUGH TONIGHT ACROSS THE AREA BUT DEFORMATION ZONE SHEARS SOMEWHAT AND EXPECT MUCH LOWER SNOWFALL RATES THAN THOSE SEEN DURING THE PERIOD OF MAX SNOWFALL/BANDING TODAY IN THE NORTHWEST. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... ISSUED AT 409 AM EST WED FEB 24 2016 FORECAST FOCUS IS ON SNOW POTENTIAL AND WIND GUSTS THURSDAY. MODELS ARE IN RELATIVELY GOOD AGREEMENT AND GENERALLY USED CONSENSUS. FOR SNOW POPS ON THURSDAY DID INCREASE FROM GUIDANCE. STILL SEE A SHORTWAVE SPOKE ON THE BACK SIDE OF THE SYSTEM THAT SWINGS THROUGH THE TROUGH TO PROVIDE SOME FORCING. SNOW SQUALL PARAMETER JUMPS UP DURING THIS TIME DUE TO SHARP LAPSE RATES SO COMBINED WITH THE FORCING EXPECT TO SEE SNOW SHOWERS DEVELOP. CONTINUED TIGHT PRESSURE GRADIENT ACROSS THE AREA WILL PRODUCE WIND GUSTS IN THE 30-40 MPH RANGE UNTIL EVENING WHEN THE GRADIENT FINALLY SLACKENS AND COMBINING THIS WITH SNOW EXPECT TO SEE SPOTS WHERE VISIBILITIES DROP DRASTICALLY FOR SHORT PERIODS OF TIME. MAY HAVE TO WIND UP EXPANDING ADVISORY BOTH EASTWARD AND IN TIME DEPENDING ON HOW SYSTEM PLAYS OUT...BUT WITH CONFIDENCE NOT AT SLAM DUNK LEVELS AND STILL 24+ HOURS OUT WILL LET NEXT SHIFT HAVE A LOOK AT LATEST GUIDANCE AND GO FROM THERE. MODELS ARE IN AGREEMENT ON DRY WEATHER THURSDAY NIGHT ON...WITH THE EXCEPTION OF A SLIGHT CHANCE FOR SNOW IN THE FAR NORTHEAST EARLY THURSDAY NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... ISSUED AT 330 AM EST WED FEB 24 2016 QUIETER WEATHER WILL BE THE RULE THIS WEEKEND AS THE UPPER FLOW BECOMES MORE ZONAL AND HIGH PRESSURE MOVES EAST ACROSS THE LOWER AND MIDDLE MISSISSIPPI VALLEY INTO THE SOUTHEASTERN U.S. MODELS MOVE AN AREA OF LOW PRESSURE EAST ACROSS THE SOUTHERN GREAT LAKES AND PULL A WEAK COLD FRONT THROUGH OUR REGION AROUND SUNDAY NIGHT. WILL CONTINUE LOW CHANCE POPS LATE SUNDAY THROUGH SUNDAY NIGHT. MOST MODELS INDICATE PRECIP WILL BE DONE AFTER 12Z MONDAY. WILL KEEP SLIGHT CHANCE POPS IN THE NORTH MONDAY NIGHT...BUT OVERALL MODEL TRENDS ARE DRIER UNTIL TUESDAY. ANOTHER SYSTEM WILL BE MOVING OUR WAY THE END OF DAY 7 AND THUS CONTINUE LOW CHANCES OF MAINLY RAIN. IN REGARDS TO TEMPERATURES STAYED CLOSE TO MODEL INITIALIZATION. && .AVIATION /DISCUSSION FOR THE 240900Z TAF ISSUANCE/... ISSUED AT 330 AM EST WED FEB 24 2016 TWEAKED KIND TAF TO BETTER MATCH CURRENT CONDITIONS. NO OTHER CHANGES ARE NEEDED AT THIS TIME. PREVIOUS AVIATION DISCUSSION FOLLOWS... RADAR AND RAPID REFRESH SUGGESTS RAIN SHIELD WILL BE OVER THE TERMINALS...EXCEPT PERHAPS LAF BY ISSUANCE TIME. ALSO...TRENDS SUGGEST VFR OR MVFR CEILINGS SHOULD LAST MOST OF THE NIGHT WITH CONDITIONS LIKELY TO DETERIORATE NEAR OR SLIGHTLY LATER THAN 12Z. THERMAL PATTERN SUGGESTS LAF SHOULD BE THE FIRST TO SEE THE RAIN CHANGE TO SNOW OR A MIX. KEPT 15Z AS A START TIME FOR THE MIX THERE WITH ALL SNOW BY 18Z. HUF SHOULD CHANGE OVER AFTER 18Z AND IND AND BMG SHOULD NOT CHANGEOVER UNTIL AFTER 00Z THURSDAY. HOWEVER... CONFIDENCE IN PRECISE TIMING OF CHANGEOVER IS NOT GREAT AS A SMALL ERROR IN TEMPERATURE FORECASTS COULD MAKE THE DIFFERENCE IN PRECIPITATION TYPE. ALTHOUGH THERE MAY BE A FEW BREAKS IN THE PRECIPITATION TODAY AND TONIGHT...FELT IT WOULD BE PRECIPITATING OVER A MAJORITY OF THE TIME AND DID NOT TRY AND GET CUTE WITH TIMING ANY BRIEF DRY PERIOD. NORTHEAST WINDS 10 TO 15 KNOTS OVERNIGHT WILL BE INCREASING A FEW KNOTS TODAY AND GUST AS HIGH AS 30 KNOTS AT LAF WITH LESSER GUSTS AT THE OTHER SITES. && .IND WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 1 PM EST THURSDAY FOR INZ037>040-045>047-051>054-060-061-067. WINTER STORM WARNING FROM 10 AM THIS MORNING TO 1 PM EST THURSDAY FOR INZ021-029>031-035-036-043-044. BLIZZARD WARNING FROM 10 AM THIS MORNING TO 1 AM EST THURSDAY FOR INZ028. && $$ SYNOPSIS...CP NEAR TERM...CP SHORT TERM...CP LONG TERM...MK/JH AVIATION...JH
AREA FORECAST DISCUSSION
NWS DES MOINES IA
534 PM CST THU FEB 25 2016 .SHORT TERM /TONIGHT/... ISSUED AT 316 PM CST THU FEB 25 2016 LITTLE OF CONCERN TONIGHT OUTSIDE OF CLOUDS. MID LEVEL VORT LOBE CONTINUES TO DROP DOWN THE MID MS VALLEY BUT ANY ENHANCED VERTICAL MOTION IS ALREADY PAST IA. UPSTREAM SASKATCHEWAN/MANITOBA SHORT WAVE IS PRODUCING A FAINT REFLECTION OF HIGH CLOUDINESS...AND WHILE THE FORCING WILL BE WEAK TO MODERATE AS IT REACHES IA EARLY FRI MORNING STILL DO NOT EXPECT ANY PRECIP DUE TO A LACK OF MOISTURE. LIKELY JUST SCATTERED MID CLOUDS. THE ONLY SENSIBLE WEATHER OF NOTE WILL BE STRATUS TRENDS WITH PATCHY HOLES PASSING BY THIS EVENING...AND HIGH RES MODELS SUGGESTING MORE GENERAL CLEARING TOWARD DAYBREAK AS UPSTREAM LOW LEVEL RIDGE CROSS THE MO RIVER VALLEY. STAYED A TOUCH OVER MOS WITH CLOUDS EXPECTED TO BE PREVALENT FOR AWHILE. .LONG TERM /FRIDAY THROUGH THURSDAY/... ISSUED AT 316 PM CST THU FEB 25 2016 FEW CONCERNS IN THE EARLY PORTION OF THE EXTENDED. HRRR AND OTHER MESOSCALE MODELS SUGGEST THAT CLOUDS WILL HOLD ON THROUGH A PORTION OF FRIDAY MORNING...THEN BREAK UP LATE IN THE AFTERNOON AS ANOTHER WEAK WAVE PASSES EAST OF THE REGION BY 00Z SATURDAY. HIGHS FRIDAY WILL MODERATE AS THE WEAK SYSTEM APPROACHES FROM THE WEST. WARM AIR ADVECTION WITH LITTLE MOISTURE TRANSITIONS EAST INTO THE AREA FOR FRIDAY NIGHT INTO THE WEEKEND. VARIOUS SOLUTIONS HAVE H850 TEMPERATURES RISING TO +11C BY 00Z SUNDAY...WITH MIXING AT LEAST TAPPING INTO 8 TO 10C AIR BY LATE DAY. WILL CONTINUE TREND OF HIGHS IN THE 50S AND 60S ON SATURDAY AS SOUTH WINDS INCREASE TO 15 TO 25 MPH DURING THE DAY. LOWS SATURDAY NIGHT WILL BE QUITE MILD AS SOUTHWEST FLOW CONTINUES. BY 12Z SUNDAY THE COLD FRONT WILL BE NEARING THE I80 CORRIDOR...BUT ENOUGH RESIDUAL WARM AIR ALOFT AND A MILD START TO THE DAY WILL HELP HIGHS REACH THE MID TO UPPER 50S SOUTH. ACROSS THE NORTH BEHIND THE BOUNDARY...LIGHT RAIN AND CLOUDS WILL BEGIN TO FILL IN OVER THE REGION. THIS WILL KEEP TEMPERATURES COOLER NORTH WITH TEMPERATURES FALLING OFF DURING THE LATE AFTERNOON HOURS. WINDS SUNDAY AFTERNOON WITH GUSTS MAY BRIEFLY APPROACH 35 TO 40 MPH WITH THE PASSAGE OF THE COLD FRONT. BY SUNDAY NIGHT INTO MONDAY...WESTERLY FLOW WILL QUICKLY DISPLACE THE SLIGHT COLD AIR ADVECTION SUNDAY EVENING. THIS WILL RESULT IN A RENEWED WARM UP MONDAY WITH HIGHS BACK IN THE 40S/50S ACROSS THE STATE. THE REMAINDER OF THE EXTENDED FEATURES A LOW CONFIDENCE FORECAST AT THIS TIME...MODELS CONTINUE AT ODDS WITH THE TRACK AND EVOLUTION OF THE EARLY NEXT WEEK SYSTEM. TODAYS CONSENSUS SHOWS THAT THE TRACK MAY BE FARTHER NORTHWEST OF THE PREVIOUS TWO MODEL RUNS...RESULTING IN THE POTENTIAL FOR MORE ADVERSE WINTER CONDITIONS ACROSS PORTIONS OF OUR FORECAST AREA. GIVEN THAT WE ARE STILL 5-6 DAYS AWAY AND MODELS INHERENTLY STRUGGLE TO REACH A CORRECT SOLUTION AT THIS TIME RANGE...WILL CONTINUE TO GO WITH CHANCE POPS FOR NOW. THE MORE NORTHWEST DRIFT IN THE MODELS THE PAST 12 HOURS THOUGH WILL NEED TO BE MONITORED. WITH THE GFS ADVERTISING A MORE WOUND UP STORM THAN THE EURO AT THIS TIME DUE TO FASTER INGESTION OF COLD CANADIAN AIR...IT ALSO HAS STRONGER WINDS AND MORE PRECIPITATION FORECAST. AGREEMENT BETWEEN MODELS ON HEAVIEST PRECIPITATION AXIS/STRENGTH /TRACK IS CURRENTLY ALSO POOR. THE GENERAL TREND FOR BOTH THE GFS/EURO OF COOLER AND DRIER AIR RETURNING TO THE REGION WEDNESDAY WITH ANOTHER FAST MOVING SYSTEM SOMETIME AROUND THURSDAY. TEMPERATURES NEXT WEEK WILL GENERALLY BE IN THE 30S/40S WITH SOME UNCERTAINTY ON TUESDAY. WILL MENTION IN UPDATED HWO THIS AFTERNOON AND PASS ONTO SUCCEEDING SHIFT. && .AVIATION...26/00Z ISSUED AT 534 PM CST THU FEB 25 2016 MVFR CIGS EXPECTED OVERNIGHT WITH CLEARING FROM DURING THE DAY FRIDAY. NORTHWEST WINDS TO DIMINISH SOME TONIGHT AND SHIFT AROUND TO THE WEST TO SOUTHWEST THROUGH THE PERIOD. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...SMALL LONG TERM...REV AVIATION...BEERENDS
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
525 AM CST WED FEB 24 2016 .UPDATE... Updated aviation section for 12z taf issuance && .SHORT TERM...(Today through Friday night) Issued at 320 AM CST WED FEB 24 2016 The main concern remains the potent storm system over our region this morning. This system contains a variety of potential hazards, including heavy snow, strong winds, heavy rain, and thunder. The heavy rain and thunder appear to be the least significant at this time. The main focus of this forecast package is on the winter weather and strong wind potential. As of 08z, the surface low was deepening rather rapidly along the Tennessee/Kentucky border near khop. RAP model data indicated the central pressure fell about 10 mb between 00z and 08z. A strong northerly low-level jet exists on the northwest side of the low. Winds aloft are forecast near 50 knots at 1000 feet agl over se Missouri this morning. There have been a few reports of 40 knot gusts in southeast MO overnight, including the kpof asos site. Model guidance indicates these strong wind fields will expand northeast across southern IL this morning. Although winds aloft will begin to weaken as they spread east this afternoon, lapse rates will steepen in the cold advection pattern. Due to more efficient momentum transfer/mixing, the Wind Advisory may need to be expanded further east across KY and into southwest IN today. Widespread moderate rain overnight has begun to change to snow in the hilly terrain of se Missouri. Around 08z, snow was reported north and west of kpof in Wayne and nw Butler Counties. At the same time, a mid-level dry slot has begun to work north across the Bootheel of Missouri. It appears the dry slot will move north- northeast in tandem with the strong mid-level low. A band of moderate to heavy precip has been organizing on the northwest side of the dry slot. The potential for a band of heavy snowfall exists under this deformation band. Mesoscale discussion 136 from the SPC contains the details on this heavy snow threat. A Winter Storm Warning will be issued for small parts of se Missouri and srn Illinois, where the deformation zone is expected to slowly organize through mid-morning. This area is generally along and northwest of a line from kcgi to kmvn. Hilly terrain in this area will provide a little extra orographic lift, along with colder temps at higher elevations. Although surface and pavement temps will be at or above freezing, snowfall rates around an inch per hour for several hours should overcome the ground warmth. The Winter Weather Advisory will continue for the rest of southeast MO and southern IL, where some bursts of snow are possible in the more unstable air within the dry slot. One last sidenote, the Winter Storm Warning will replace the Wind Advisory, since the wind hazard is covered by the warning. The main area of precip will exit our region by early this afternoon, but areas of lighter precip will continue to wrap south-southeastward around the departing occluded low through tonight. Most of this wrap-around precip will be along and east of the Mississippi River, and mainly in the form of snow. However, surface temps are forecast to remain above freezing for most of the night. Any additional snow amounts are forecast to be less than one-half inch and mainly in southwest IN and the Pennyrile region. Therefore, the winter headlines will not be extended into the night with this forecast package. There may be some lingering light snow showers in the EVV area and Pennyrile region of west KY on Thursday. Otherwise, relatively quiet weather is expected Thursday into Friday as surface high pressure builds east across our region. Forecast highs will be lowered a notch for Thursday based on anticipated snow cover in some areas. In addition, forecast 850 mb temps of minus 10 do not support highs in the 40s, especially with the anticipated cloud cover. With increasing sun and moderating 850 mb temps on Friday, highs will be in the 40s. .LONG TERM...(Saturday through Tuesday) Issued at 320 AM CST WED FEB 24 2016 Above average confidence in the long term. High pressure at the surface and weak ridging aloft should keep the region dry through Sunday. With the approach and passage of a frontal system Sunday night, precipitation chances will be small due to a lack of moisture. High pressure in the wake of the front will keep the region dry through at least Monday, and maybe even Monday night. Models not in good agreement regarding the results of a cold front dropping southward out of the northern plains Monday into Monday evening. The GFS brings the front across our CWA dry while the ECMWF brings the front into our CWA, then stalls it out E-W. After midnight Monday night the ECMWF brings a swath of QPF quickly eastward along the boundary across our CWA while the GFS continues to be dry. With so much disparity, decided to keep it dry Monday night. Models show the aforementioned frontal boundary lifting back to the north as a warm front on Tuesday. Again the GFS remains dry with the fropa while the ECMWF cranks out precipitation for basically the entire area. Decided to split the difference in this period and go with small pops. Temperatures will remain above normal through the long term period, and thankfully any precipitation that falls should be of the liquid variety. && .AVIATION... Issued at 525 AM CST WED FEB 24 2016 IFR cigs/vsbys will remain prevalent through today as a strong storm system and its associated precipitation impact the taf sites. Conditions will improve this evening as winds become northwest and bring drier air. Rain will transition to snow from west to east, starting at kcgi early this morning and finally changing near KOWB and KEVV this afternoon. Sustained winds at or above 15 kts will continue until tonight when the system exits to the east. Gusts will be around 30 knots today. && .PAH Watches/Warnings/Advisories... IL...Winter Weather Advisory until 6 PM CST this evening for ILZ075>078-080>086-088-089-092-093. Wind Advisory until 6 PM CST this evening for ILZ076>078-082-083- 085>094. Winter Storm Warning until 6 PM CST this evening for ILZ075-080- 081-084. MO...Winter Weather Advisory until 6 PM CST this evening for MOZ076- 086-087-100-107>112-114. Wind Advisory until 6 PM CST this evening for MOZ100-107>112-114. Winter Storm Warning until 6 PM CST this evening for MOZ076-086- 087. IN...NONE. KY...Wind Advisory until 6 PM CST this evening for KYZ001>006. && $$ SHORT TERM...MY LONG TERM...JP AVIATION...MY
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
320 AM CST WED FEB 24 2016 .SHORT TERM...(Today through Friday night) Issued at 320 AM CST WED FEB 24 2016 The main concern remains the potent storm system over our region this morning. This system contains a variety of potential hazards, including heavy snow, strong winds, heavy rain, and thunder. The heavy rain and thunder appear to be the least significant at this time. The main focus of this forecast package is on the winter weather and strong wind potential. As of 08z, the surface low was deepening rather rapidly along the Tennessee/Kentucky border near khop. RAP model data indicated the central pressure fell about 10 mb between 00z and 08z. A strong northerly low-level jet exists on the northwest side of the low. Winds aloft are forecast near 50 knots at 1000 feet agl over se Missouri this morning. There have been a few reports of 40 knot gusts in southeast MO overnight, including the kpof asos site. Model guidance indicates these strong wind fields will expand northeast across southern IL this morning. Although winds aloft will begin to weaken as they spread east this afternoon, lapse rates will steepen in the cold advection pattern. Due to more efficient momentum transfer/mixing, the Wind Advisory may need to be expanded further east across KY and into southwest IN today. Widespread moderate rain overnight has begun to change to snow in the hilly terrain of se Missouri. Around 08z, snow was reported north and west of kpof in Wayne and nw Butler Counties. At the same time, a mid-level dry slot has begun to work north across the Bootheel of Missouri. It appears the dry slot will move north- northeast in tandem with the strong mid-level low. A band of moderate to heavy precip has been organizing on the northwest side of the dry slot. The potential for a band of heavy snowfall exists under this deformation band. Mesoscale discussion 136 from the SPC contains the details on this heavy snow threat. A Winter Storm Warning will be issued for small parts of se Missouri and srn Illinois, where the deformation zone is expected to slowly organize through mid-morning. This area is generally along and northwest of a line from kcgi to kmvn. Hilly terrain in this area will provide a little extra orographic lift, along with colder temps at higher elevations. Although surface and pavement temps will be at or above freezing, snowfall rates around an inch per hour for several hours should overcome the ground warmth. The Winter Weather Advisory will continue for the rest of southeast MO and southern IL, where some bursts of snow are possible in the more unstable air within the dry slot. One last sidenote, the Winter Storm Warning will replace the Wind Advisory, since the wind hazard is covered by the warning. The main area of precip will exit our region by early this afternoon, but areas of lighter precip will continue to wrap south-southeastward around the departing occluded low through tonight. Most of this wrap-around precip will be along and east of the Mississippi River, and mainly in the form of snow. However, surface temps are forecast to remain above freezing for most of the night. Any additional snow amounts are forecast to be less than one-half inch and mainly in southwest IN and the Pennyrile region. Therefore, the winter headlines will not be extended into the night with this forecast package. There may be some lingering light snow showers in the EVV area and Pennyrile region of west KY on Thursday. Otherwise, relatively quiet weather is expected Thursday into Friday as surface high pressure builds east across our region. Forecast highs will be lowered a notch for Thursday based on anticipated snow cover in some areas. In addition, forecast 850 mb temps of minus 10 do not support highs in the 40s, especially with the anticipated cloud cover. With increasing sun and moderating 850 mb temps on Friday, highs will be in the 40s. .LONG TERM...(Saturday through Tuesday) Issued at 320 AM CST WED FEB 24 2016 Above average confidence in the long term. High pressure at the surface and weak ridging aloft should keep the region dry through Sunday. With the approach and passage of a frontal system Sunday night, precipitation chances will be small due to a lack of moisture. High pressure in the wake of the front will keep the region dry through at least Monday, and maybe even Monday night. Models not in good agreement regarding the results of a cold front dropping southward out of the northern plains Monday into Monday evening. The GFS brings the front across our CWA dry while the ECMWF brings the front into our CWA, then stalls it out E-W. After midnight Monday night the ECMWF brings a swath of QPF quickly eastward along the boundary across our CWA while the GFS continues to be dry. With so much disparity, decided to keep it dry Monday night. Models show the aforementioned frontal boundary lifting back to the north as a warm front on Tuesday. Again the GFS remains dry with the fropa while the ECMWF cranks out precipitation for basically the entire area. Decided to split the difference in this period and go with small pops. Temperatures will remain above normal through the long term period, and thankfully any precipitation that falls should be of the liquid variety. && .AVIATION... Issued at 1148 PM CST TUE FEB 23 2016 Expect MVFR and IFR cigs/vsbys through the period with perhaps some LIFR cigs as a strong storm system and its associated precipitation impact the Quad State area. Conditions will deteriorate this morning as northerly winds gradually increase and become gusty. Rain will transition to snow from west to east, starting in SE MO in the morning and finally changing near KOWB and KEVV by the evening. Snow and sustained winds AOA 15 kts will continue until Wednesday night when the system exits to the east. && .PAH Watches/Warnings/Advisories... IL...Winter Weather Advisory until 6 PM CST this evening for ILZ075>078-080>086-088-089-092-093. Wind Advisory until 6 PM CST this evening for ILZ076>078-082-083- 085>094. Winter Storm Warning until 6 PM CST this evening for ILZ075-080- 081-084. MO...Winter Weather Advisory until 6 PM CST this evening for MOZ076- 086-087-100-107>112-114. Wind Advisory until 6 PM CST this evening for MOZ100-107>112-114. Winter Storm Warning until 6 PM CST this evening for MOZ076-086- 087. IN...NONE. KY...Wind Advisory until 6 PM CST this evening for KYZ001>006. && $$ SHORT TERM...MY LONG TERM...JP AVIATION...BP2
AREA FORECAST DISCUSSION
NWS GRAY ME
1155 AM EST WED FEB 24 2016 .SYNOPSIS... WE`LL SEE A LIGHT WINTRY MIX TODAY AS WARMER AIR MOVES INTO THE REGION ALOFT AHEAD OF A MUCH STRONGER LOW PRESSURE SYSTEM. THIS LOW WILL MOVE WEST OF THE REGION TONIGHT AND THURSDAY...BRINGING A ROUND OF HEAVY RAINFALL TO THE REGION AS TEMPERATURES WARM WELL ABOVE SEASONAL NORMS. MUCH COOLER AIR WILL FLOW BACK INTO THE REGION TO END THE WEEK. ANOTHER LOW PRESSURE SYSTEM WILL PASS NORTH OF THE REGION SUNDAY NIGHT AND MONDAY AND WILL DRAG A COLD FRONT ACROSS THE REGION LATE MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1155 AM...TEMPERATURES CONTINUE TO SLOWLY CLIMB ACROSS THE FORECAST AREA. THE WINTER WEATHER ADVISORY FOR COASTAL SECTIONS AS WELL AS SOUTHEAST NEW HAMPSHIRE WILL BE ALLOWED TO EXPIRE AT NOON AS SURFACE TEMPERATURES WARM SLOWLY ABOVE FREEZING. PREV DISC... 945 AM...LATEST SURFACE ANALYSIS SHOWS COLD AIR IS SLOW TO ERODE...EVEN SLOWER THEN MESOSCALE MODELS WOULD SUGGEST. LIGHT MIXED PRECIPITATION WILL CONTINUE WITH AREAS OF FREEZING DRIZZLE OVER SOUTHERN AND COASTAL SECTIONS. I OPTED TO EXTEND THE WINTER WEATHER ADVISORIES UNTIL NOON FOR AREAS OF LIGHT FREEZING RAIN/DRIZZLE OVER SOUTHEAST NEW HAMPSHIRE AS WELL AS COASTAL MAINE. PREV DISC... UPDATE... COLD AIR HOLDING IN TOUGH WITH A NORTHERLY COMPONENT TO THE WIND FIELDS EVEN ALONG THE COAST. HAVE EXPANDED TO INCLUDE A BRIEF WINTER WEATHER ADVISORY FOR THE COASTLINE AS WELL...WITH TEMPERATURES RUNNING IN THE UPPER 20S TO LOWER 30S AND THE PRECIPITATION BEGINNING TO CHANGE OVER TO FREEZING RAIN IN SPOTS. FREEZING RAIN NOW OCCURRING FROM PORTSMOUTH NORTHWARD THROUGH THE PORTLAND AREA ALONG THE COASTLINE. WISCASSET AND ROCKLAND MAY CHANGEOVER AROUND 13Z. THE LATEST HRRR IS BEGINNING TO HAVE A GOOD HANDLE ON THIS DELAY IN THE BOUNDRY LAYER/SURFACE WARMING. THIS NEW ADVISORY WILL BE IN AFFECT UNTIL 10 AM. HAVE ALSO EXPANDED THE ADVISORY UNTIL 10 AM ACROSS INTERIOR ROCKINGHAM COUNTY AS WELL. PREV DISC... A VERY COMPLEX SCENARIO CONTINUES AS COLD ARCTIC AIR REMAINS IN PLACE IN A SHALLOW LAYER NEAR THE SURFACE OVER MAIND AND NEW HAMPSHIRE. HOWEVER...VERY WARM AIR CONTINUES TO ENTER THE REGION ALOFT. PRECIPITATION EARLY THIS MORNING ASSOCIATED WITH THE FIRST INITIAL SHORT WAVE REMAINS IN THE FORM OF SNOW FOR MOST AREAS. EXPECT THE PRECIP TO CHANGE TO RAIN TODAY ALONG THE COAST AS A STRONG EASTERLY FLOW CONTINUES NEAR/ALONG THE COASTAL FRONT. FURTHER INLAND...THE PRECIP WILL CHANGE TO SLEET AND FREEZING RAIN AFTER A FEW INCHES OF SNOW ACCUMULATES. ELEVATIONS AROUND 1500 FEET MAY HOLD ONTO THE FREEZING RAIN THE LONGEST WITH A FEW LOCATIONS PICKING UP CLOSE TO A HALF INCH OF ICE ACCRETION. MODELS ARE IN RELATIVELY GOOD AGREEMENT WITH THE FEATURES IN THIS COMPLEX SYSTEM WITH THE MODEL ENSEMBLES PLACING THE MAIN UPPER LEVEL LOW PRESSURE SYSTEM MOVING QUICKLY TO THE NORTH FROM THE SOUTHERN OHIO VALLEY BY LATER TODAY. MESOSCALE MODELS SUGGEST THERE COULD BE A LULL IN THE PRECIPITATION BY THE TIME WE REACH THE MIDDAY HOURS. THIS MAY ALLOW THE PRECIP TO CHANGE TO A FREEZING DRIZZLE OR DRIZZLE IN SOME AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... MAIN...LARGE SCALE SYNOPTIC SYSTEM APPROACHES TONIGHT AS CYCLOGENESIS CONTINUES AS THE SURFACE LOW REACHES UPSTATE NEW YORK. A STRONG LOW LEVEL JET WILL ADVECT WARM...MOIST AIR. HIGH PWAT AND POLEWARD WIND VALUES CONTINUE TO BE FORECAST IN A HIGHLY ANOMALOUS EVENT. EXPECT THE RAIN TO BECOME HEAVY AFTER MIDNIGHT. THE ATMOSPHERE WILL REMAIN UNSTABLE WITH CONVECTION FORMING LATE AT NIGHT WITH SCATTERED THUNDERSTORMS CONTINUING INTO EARLY THURSDAY. LOCALLY HEAVY RAIN WILL CONTINUE EARLY THURSDAY MORNING AHEAD OF THE STRONG APPROACHING COLD FRONT. A DRY SLOT WILL ALLOW FOR THE PRECIP TO BECOME LIGHT DURING THE LATE MORNING AND AFTERNOON HOURS. MODELS ARE NOW IN FAIRLY GOOD AGREEMENT WITH THE TIMING OF THE PASSAGE OF THE COLD FRONT. WINDS WILL INCREASE OUT OF THE SOUTH LATER TONIGHT AND EARLY THURSDAY MORNING. WIND GUSTS TO 50 MPH ARE POSSIBLE ALONG THE COAST. THESE HIGH WINDS WILL ARRIVE ON AN INCREASING MIXING LAYER AND STRONG LOW LEVEL JET. THIS WARM AIR ADVECTION WILL ALLOW READINGS TO SOAR INTO THE 50S IN SOME AREAS. THE RECORD HIGH IN PORTLAND FOR THURSDAY IS 51 WHICH WILL LIKELY BE BROKEN. THE PREVIOUS RECORD WAS SET IN 1984 AND 1985. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... A COLD FRONT WILL CROSS THE REGION THURSDAY NIGHT BRINGING THE RETURN OF COLDER TEMPERATURES FRIDAY INTO THE WEEKEND. MODELS NOT IN GOOD AGREEMENT ON THE MAGNITUDE OF THE COLDER AIR WITH THE NAM MOS QUITE A BIT COLDER THAN THE GFS. HAVE USED A BLEND WHICH SEEMS MORE REASONABLE. THE FRONT COULD BE ACCOMPANIED BY SOME RAIN SHOWERS WHICH EVENTUALLY WILL CHANGE TO SNOW SHOWERS AS THE COLDER AIR MOVES INTO THE REGION THURSDAY NIGHT. A RIDGE OF HIGH PRESSURE WILL BUILD INTO THE AREA SATURDAY THEN WILL MOVE EAST OF THE AREA SATURDAY NIGHT AND SUNDAY. WARM ADVECTION ON THE BACK SIDE OF THE RIDGE WILL BRING MORE CLOUDS INTO THE REGION SUNDAY AS LOW PRESSURE APPROACHES FROM THE WEST. THIS WILL BRING INCREASING CHANCES FOR PRECIPITATION, FIRST AS SNOW SHOWERS SUNDAY NIGHT, THEN RAIN SHOWERS MONDAY AS THE LOW MOVES NORTH OF THE AREA. A COLD FRONT IS EXPECTED TO CROSS THE AREA LATE MONDAY BRINGING A RETURN OF COLDER AIR AND WITH THE POSSIBILITY THAT ANY RAIN SHOWERS MAY CHANGE BACK TO SNOW SHOWERS. AHEAD OF THE FRONT MONDAY, ESPECIALLY SOUTHERN AND COASTAL AREAS WILL SEE ANOTHER WARM DAY TO FINISH OUT THE MONTH OF FEBRUARY. COLDER AIR WILL RETURN TO THE REGION FOR TUESDAY AND WEDNESDAY. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... SHORT TERM...MOST AREAS WILL DETEORATE TO LIFR CONDITIONS. MIXED PRECIPITATION WITH ICING EXPECTED TODAY INTO TONIGHT. EXPECT WIND SHEAR TO DEVELOP AS SURFACE WINDS REMAIN LIGHT FROM THE NORTHEAST...BUT WINDS INCREASE SIGNIFICANTLY ALOFT LATER TODAY AND TONIGHT. LONG TERM...IFR TO MVFR CONDITIONS THURSDAY NIGHT WILL IMPROVE TO VFR FRIDAY. VFR CONDITIONS EXPECTED SATURDAY AND SUNDAY...EXCEPT IN THE MOUNTAINS WHERE MVFR CONDITIONS ARE POSSIBLE IN SNOW SHOWERS. && .MARINE... SHORT TERM...SCA CONDITIONS EXPECTED THURSDAY NIGHT AND FRIDAY AND AGAIN SUNDAY AND MONDAY LONG TERM...GALE WARNINGS ARE NOW IN EFFECT FOR ALL OF OUR WATERS. WINDS WILL INCREASE OUT OF THE SOUTH TONIGHT WITH BUILDING SEAS. && .HYDROLOGY... RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE EXPECTED THROUGH THURSDAY AFTER SOME SNOW...SLEET...AND FREEZING RAIN. LOCALIZED AMOUNTS OF 3 TO 3.5 INCHES WILL BE POSSIBLE ON THE EAST-SOUTHEAST FACING SLOPES OF THE WHITES AND MAINE FOOTHILLS. THIS MAY POSE SOME MINOR FLOODING PROBLEMS FOR POOR DRAINAGE AREAS AS WELL AS SIGNIFICANT RISES FOR THE SACO...PEMI...AND SWIFT RIVERS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MEZ018- 019. WINTER WEATHER ADVISORY UNTIL 5 AM EST THURSDAY FOR MEZ007>009- 012>014-020>022. NH...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NHZ005>011-015. WINTER WEATHER ADVISORY UNTIL 5 AM EST THURSDAY FOR NHZ001>004. MARINE...GALE WARNING FROM 11 PM THIS EVENING TO 1 PM EST THURSDAY FOR ANZ151-153. GALE WARNING FROM 11 PM THIS EVENING TO 7 PM EST THURSDAY FOR ANZ150-152-154. && $$ ES
AREA FORECAST DISCUSSION
NWS GRAY ME
951 AM EST WED FEB 24 2016 .SYNOPSIS... WE`LL SEE A LIGHT WINTRY MIX TODAY AS WARMER AIR MOVES INTO THE REGION ALOFT AHEAD OF A MUCH STRONGER LOW PRESSURE SYSTEM. THIS LOW WILL MOVE WEST OF THE REGION TONIGHT AND THURSDAY...BRINGING A ROUND OF HEAVY RAINFALL TO THE REGION AS TEMPERATURES WARM WELL ABOVE SEASONAL NORMS. MUCH COOLER AIR WILL FLOW BACK INTO THE REGION TO END THE WEEK. ANOTHER LOW PRESSURE SYSTEM WILL PASS NORTH OF THE REGION SUNDAY NIGHT AND MONDAY AND WILL DRAG A COLD FRONT ACROSS THE REGION LATE MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 945 AM...LATEST SURFACE ANALYSIS SHOWS COLD AIR IS SLOW TO ERODE...EVEN SLOWER THEN MESOSCALE MODELS WOULD SUGGEST. LIGHT MIXED PRECIPITATION WILL CONTINUE WITH AREAS OF FREEZING DRIZZLE OVER SOUTHERN AND COASTAL SECTIONS. I OPTED TO EXTEND THE WINTER WEATHER ADVISORIES UNTIL NOON FOR AREAS OF LIGHT FREEZING RAIN/DRIZZLE OVER SOUTHEAST NEW HAMPSHIRE AS WELL AS COASTAL MAINE. PREV DISC... UPDATE... COLD AIR HOLDING IN TOUGH WITH A NORTHERLY COMPONENT TO THE WIND FIELDS EVEN ALONG THE COAST. HAVE EXPANDED TO INCLUDE A BRIEF WINTER WEATHER ADVISORY FOR THE COASTLINE AS WELL...WITH TEMPERATURES RUNNING IN THE UPPER 20S TO LOWER 30S AND THE PRECIPITATION BEGINNING TO CHANGE OVER TO FREEZING RAIN IN SPOTS. FREEZING RAIN NOW OCCURRING FROM PORTSMOUTH NORTHWARD THROUGH THE PORTLAND AREA ALONG THE COASTLINE. WISCASSET AND ROCKLAND MAY CHANGEOVER AROUND 13Z. THE LATEST HRRR IS BEGINNING TO HAVE A GOOD HANDLE ON THIS DELAY IN THE BOUNDRY LAYER/SURFACE WARMING. THIS NEW ADVISORY WILL BE IN AFFECT UNTIL 10 AM. HAVE ALSO EXPANDED THE ADVISORY UNTIL 10 AM ACROSS INTERIOR ROCKINGHAM COUNTY AS WELL. PREV DISC... A VERY COMPLEX SCENARIO CONTINUES AS COLD ARCTIC AIR REMAINS IN PLACE IN A SHALLOW LAYER NEAR THE SURFACE OVER MAIND AND NEW HAMPSHIRE. HOWEVER...VERY WARM AIR CONTINUES TO ENTER THE REGION ALOFT. PRECIPITATION EARLY THIS MORNING ASSOCIATED WITH THE FIRST INITIAL SHORT WAVE REMAINS IN THE FORM OF SNOW FOR MOST AREAS. EXPECT THE PRECIP TO CHANGE TO RAIN TODAY ALONG THE COAST AS A STRONG EASTERLY FLOW CONTINUES NEAR/ALONG THE COASTAL FRONT. FURTHER INLAND...THE PRECIP WILL CHANGE TO SLEET AND FREEZING RAIN AFTER A FEW INCHES OF SNOW ACCUMULATES. ELEVATIONS AROUND 1500 FEET MAY HOLD ONTO THE FREEZING RAIN THE LONGEST WITH A FEW LOCATIONS PICKING UP CLOSE TO A HALF INCH OF ICE ACCRETION. MODELS ARE IN RELATIVELY GOOD AGREEMENT WITH THE FEATURES IN THIS COMPLEX SYSTEM WITH THE MODEL ENSEMBLES PLACING THE MAIN UPPER LEVEL LOW PRESSURE SYSTEM MOVING QUICKLY TO THE NORTH FROM THE SOUTHERN OHIO VALLEY BY LATER TODAY. MESOSCALE MODELS SUGGEST THERE COULD BE A LULL IN THE PRECIPITATION BY THE TIME WE REACH THE MIDDAY HOURS. THIS MAY ALLOW THE PRECIP TO CHANGE TO A FREEZING DRIZZLE OR DRIZZLE IN SOME AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... MAIN...LARGE SCALE SYNOPTIC SYSTEM APPROACHES TONIGHT AS CYCLOGENESIS CONTINUES AS THE SURFACE LOW REACHES UPSTATE NEW YORK. A STRONG LOW LEVEL JET WILL ADVECT WARM...MOIST AIR. HIGH PWAT AND POLEWARD WIND VALUES CONTINUE TO BE FORECAST IN A HIGHLY ANOMALOUS EVENT. EXPECT THE RAIN TO BECOME HEAVY AFTER MIDNIGHT. THE ATMOSPHERE WILL REMAIN UNSTABLE WITH CONVECTION FORMING LATE AT NIGHT WITH SCATTERED THUNDERSTORMS CONTINUING INTO EARLY THURSDAY. LOCALLY HEAVY RAIN WILL CONTINUE EARLY THURSDAY MORNING AHEAD OF THE STRONG APPROACHING COLD FRONT. A DRY SLOT WILL ALLOW FOR THE PRECIP TO BECOME LIGHT DURING THE LATE MORNING AND AFTERNOON HOURS. MODELS ARE NOW IN FAIRLY GOOD AGREEMENT WITH THE TIMING OF THE PASSAGE OF THE COLD FRONT. WINDS WILL INCREASE OUT OF THE SOUTH LATER TONIGHT AND EARLY THURSDAY MORNING. WIND GUSTS TO 50 MPH ARE POSSIBLE ALONG THE COAST. THESE HIGH WINDS WILL ARRIVE ON AN INCREASING MIXING LAYER AND STRONG LOW LEVEL JET. THIS WARM AIR ADVECTION WILL ALLOW READINGS TO SOAR INTO THE 50S IN SOME AREAS. THE RECORD HIGH IN PORTLAND FOR THURSDAY IS 51 WHICH WILL LIKELY BE BROKEN. THE PREVIOUS RECORD WAS SET IN 1984 AND 1985. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... A COLD FRONT WILL CROSS THE REGION THURSDAY NIGHT BRINGING THE RETURN OF COLDER TEMPERATURES FRIDAY INTO THE WEEKEND. MODELS NOT IN GOOD AGREEMENT ON THE MAGNITUDE OF THE COLDER AIR WITH THE NAM MOS QUITE A BIT COLDER THAN THE GFS. HAVE USED A BLEND WHICH SEEMS MORE REASONABLE. THE FRONT COULD BE ACCOMPANIED BY SOME RAIN SHOWERS WHICH EVENTUALLY WILL CHANGE TO SNOW SHOWERS AS THE COLDER AIR MOVES INTO THE REGION THURSDAY NIGHT. A RIDGE OF HIGH PRESSURE WILL BUILD INTO THE AREA SATURDAY THEN WILL MOVE EAST OF THE AREA SATURDAY NIGHT AND SUNDAY. WARM ADVECTION ON THE BACK SIDE OF THE RIDGE WILL BRING MORE CLOUDS INTO THE REGION SUNDAY AS LOW PRESSURE APPROACHES FROM THE WEST. THIS WILL BRING INCREASING CHANCES FOR PRECIPITATION, FIRST AS SNOW SHOWERS SUNDAY NIGHT, THEN RAIN SHOWERS MONDAY AS THE LOW MOVES NORTH OF THE AREA. A COLD FRONT IS EXPECTED TO CROSS THE AREA LATE MONDAY BRINGING A RETURN OF COLDER AIR AND WITH THE POSSIBILITY THAT ANY RAIN SHOWERS MAY CHANGE BACK TO SNOW SHOWERS. AHEAD OF THE FRONT MONDAY, ESPECIALLY SOUTHERN AND COASTAL AREAS WILL SEE ANOTHER WARM DAY TO FINISH OUT THE MONTH OF FEBRUARY. COLDER AIR WILL RETURN TO THE REGION FOR TUESDAY AND WEDNESDAY. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...MOST AREAS WILL DETEORATE TO LIFR CONDITIONS. MIXED PRECIPITATION WITH ICING EXPECTED TODAY INTO TONIGHT. EXPECT WIND SHEAR TO DEVELOP AS SURFACE WINDS REMAIN LIGHT FROM THE NORTHEAST...BUT WINDS INCREASE SIGNIFICANTLY ALOFT LATER TODAY AND TONIGHT. LONG TERM...IFR TO MVFR CONDITIONS THURSDAY NIGHT WILL IMPROVE TO VFR FRIDAY. VFR CONDITIONS EXPECTED SATURDAY AND SUNDAY...EXCEPT IN THE MOUNTAINS WHERE MVFR CONDITIONS ARE POSSIBLE IN SNOW SHOWERS. && .MARINE... SHORT TERM...SCA CONDITIONS EXPECTED THURSDAY NIGHT AND FRIDAY AND AGAIN SUNDAY AND MONDAY LONG TERM...GALE WARNINGS ARE NOW IN EFFECT FOR ALL OF OUR WATERS. WINDS WILL INCREASE OUT OF THE SOUTH TONIGHT WITH BUILDING SEAS. && .HYDROLOGY... RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE EXPECTED THROUGH THURSDAY AFTER SOME SNOW...SLEET...AND FREEZING RAIN. LOCALIZED AMOUNTS OF 3 TO 3.5 INCHES WILL BE POSSIBLE ON THE EAST-SOUTHEAST FACING SLOPES OF THE WHITES AND MAINE FOOTHILLS. THIS MAY POSE SOME MINOR FLOODING PROBLEMS FOR POOR DRAINAGE AREAS AS WELL AS SIGNIFICANT RISES FOR THE SACO...PEMI...AND SWIFT RIVERS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MEZ018- 019. WINTER WEATHER ADVISORY UNTIL 5 AM EST THURSDAY FOR MEZ007>009- 012>014-020>022. WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR MEZ023>028. NH...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NHZ005>011-015. WINTER WEATHER ADVISORY UNTIL 5 AM EST THURSDAY FOR NHZ001>004. WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR NHZ012>014. MARINE...GALE WARNING FROM 11 PM THIS EVENING TO 1 PM EST THURSDAY FOR ANZ151-153. GALE WARNING FROM 11 PM THIS EVENING TO 7 PM EST THURSDAY FOR ANZ150-152-154. && $$ ES
AREA FORECAST DISCUSSION
NWS GRAY ME
712 AM EST WED FEB 24 2016 .SYNOPSIS... THE SNOW WILL CHANGE TO A WINTRY MIX TODAY AS WARMER AIR BEGINS TO MOVE INTO THE REGION ALOFT AHEAD OF A MUCH STRONGER LOW PRESSURE SYSTEM. THIS LOW WILL MOVE WEST OF THE REGION TONIGHT AND THURSDAY...BRINGING A ROUND OF HEAVY RAINFALL TO THE REGION AS TEMPERATURES WARM WELL ABOVE SEASONAL NORMS. MUCH COOLER AIR WILL FLOW BACK INTO THE REGION TO END THE WEEK. ANOTHER LOW PRESSURE SYSTEM WILL PASS NORTH OF THE REGION SUNDAY NIGHT AND MONDAY AND WILL DRAG A COLD FRONT ACROSS THE REGION LATE MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATE... COLD AIR HOLDING IN TOUGH WITH A NORTHERLY COMPONENT TO THE WIND FIELDS EVEN ALONG THE COAST. HAVE EXPANDED TO INCLUDE A BRIEF WINTER WEATHER ADVISORY FOR THE COASTLINE AS WELL...WITH TEMPERATURES RUNNING IN THE UPPER 20S TO LOWER 30S AND THE PRECIPITATION BEGINNING TO CHANGE OVER TO FREEZING RAIN IN SPOTS. FREEZING RAIN NOW OCCURRING FROM PORTSMOUTH NORTHWARD THROUGH THE PORTLAND AREA ALONG THE COASTLINE. WISCASSET AND ROCKLAND MAY CHANGEOVER AROUND 13Z. THE LATEST HRRR IS BEGINNING TO HAVE A GOOD HANDLE ON THIS DELAY IN THE BOUNDRY LAYER/SURFACE WARMING. THIS NEW ADVISORY WILL BE IN AFFECT UNTIL 10 AM. HAVE ALSO EXPANDED THE ADVISORY UNTIL 10 AM ACROSS INTERIOR ROCKINGHAM COUNTY AS WELL. PREV DISC... A VERY COMPLEX SCENARIO CONTINUES AS COLD ARCTIC AIR REMAINS IN PLACE IN A SHALLOW LAYER NEAR THE SURFACE OVER MAIND AND NEW HAMPSHIRE. HOWEVER...VERY WARM AIR CONTINUES TO ENTER THE REGION ALOFT. PRECIPITATION EARLY THIS MORNING ASSOCIATED WITH THE FIRST INITIAL SHORT WAVE REMAINS IN THE FORM OF SNOW FOR MOST AREAS. EXPECT THE PRECIP TO CHANGE TO RAIN TODAY ALONG THE COAST AS A STRONG EASTERLY FLOW CONTINUES NEAR/ALONG THE COASTAL FRONT. FURTHER INLAND...THE PRECIP WILL CHANGE TO SLEET AND FREEZING RAIN AFTER A FEW INCHES OF SNOW ACCUMULATES. ELEVATIONS AROUND 1500 FEET MAY HOLD ONTO THE FREEZING RAIN THE LONGEST WITH A FEW LOCATIONS PICKING UP CLOSE TO A HALF INCH OF ICE ACCRETION. MODELS ARE IN RELATIVELY GOOD AGREEMENT WITH THE FEATURES IN THIS COMPLEX SYSTEM WITH THE MODEL ENSEMBLES PLACING THE MAIN UPPER LEVEL LOW PRESSURE SYSTEM MOVING QUICKLY TO THE NORTH FROM THE SOUTHERN OHIO VALLEY BY LATER TODAY. MESOSCALE MODELS SUGGEST THERE COULD BE A LULL IN THE PRECIPITATION BY THE TIME WE REACH THE MIDDAY HOURS. THIS MAY ALLOW THE PRECIP TO CHANGE TO A FREEZING DRIZZLE OR DRIZZLE IN SOME AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... MAIN...LARGE SCALE SYNOPTIC SYSTEM APPROACHES TONIGHT AS CYCLOGENESIS CONTINUES AS THE SURFACE LOW REACHES UPSTATE NEW YORK. A STRONG LOW LEVEL JET WILL ADVECT WARM...MOIST AIR. HIGH PWAT AND POLEWARD WIND VALUES CONTINUE TO BE FORECAST IN A HIGHLY ANOMALOUS EVENT. EXPECT THE RAIN TO BECOME HEAVY AFTER MIDNIGHT. THE ATMOSPHERE WILL REMAIN UNSTABLE WITH CONVECTION FORMING LATE AT NIGHT WITH SCATTERED THUNDERSTORMS CONTINUING INTO EARLY THURSDAY. LOCALLY HEAVY RAIN WILL CONTINUE EARLY THURSDAY MORNING AHEAD OF THE STRONG APPROACHING COLD FRONT. A DRY SLOT WILL ALLOW FOR THE PRECIP TO BECOME LIGHT DURING THE LATE MORNING AND AFTERNOON HOURS. MODELS ARE NOW IN FAIRLY GOOD AGREEMENT WITH THE TIMING OF THE PASSAGE OF THE COLD FRONT. WINDS WILL INCREASE OUT OF THE SOUTH LATER TONIGHT AND EARLY THURSDAY MORNING. WIND GUSTS TO 50 MPH ARE POSSIBLE ALONG THE COAST. THESE HIGH WINDS WILL ARRIVE ON AN INCREASING MIXING LAYER AND STRONG LOW LEVEL JET. THIS WARM AIR ADVECTION WILL ALLOW READINGS TO SOAR INTO THE 50S IN SOME AREAS. THE RECORD HIGH IN PORTLAND FOR THURSDAY IS 51 WHICH WILL LIKELY BE BROKEN. THE PREVIOUS RECORD WAS SET IN 1984 AND 1985. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... A COLD FRONT WILL CROSS THE REGION THURSDAY NIGHT BRINGING THE RETURN OF COLDER TEMPERATURES FRIDAY INTO THE WEEKEND. MODELS NOT IN GOOD AGREEMENT ON THE MAGNITUDE OF THE COLDER AIR WITH THE NAM MOS QUITE A BIT COLDER THAN THE GFS. HAVE USED A BLEND WHICH SEEMS MORE REASONABLE. THE FRONT COULD BE ACCOMPANIED BY SOME RAIN SHOWERS WHICH EVENTUALLY WILL CHANGE TO SNOW SHOWERS AS THE COLDER AIR MOVES INTO THE REGION THURSDAY NIGHT. A RIDGE OF HIGH PRESSURE WILL BUILD INTO THE AREA SATURDAY THEN WILL MOVE EAST OF THE AREA SATURDAY NIGHT AND SUNDAY. WARM ADVECTION ON THE BACK SIDE OF THE RIDGE WILL BRING MORE CLOUDS INTO THE REGION SUNDAY AS LOW PRESSURE APPROACHES FROM THE WEST. THIS WILL BRING INCREASING CHANCES FOR PRECIPITATION, FIRST AS SNOW SHOWERS SUNDAY NIGHT, THEN RAIN SHOWERS MONDAY AS THE LOW MOVES NORTH OF THE AREA. A COLD FRONT IS EXPECTED TO CROSS THE AREA LATE MONDAY BRINGING A RETURN OF COLDER AIR AND WITH THE POSSIBILITY THAT ANY RAIN SHOWERS MAY CHANGE BACK TO SNOW SHOWERS. AHEAD OF THE FRONT MONDAY, ESPECIALLY SOUTHERN AND COASTAL AREAS WILL SEE ANOTHER WARM DAY TO FINISH OUT THE MONTH OF FEBRUARY. COLDER AIR WILL RETURN TO THE REGION FOR TUESDAY AND WEDNESDAY. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...MOST AREAS WILL DETEORATE TO LIFR CONDITIONS. MIXED PRECIPITATION WITH ICING EXPECTED TODAY INTO TONIGHT. EXPECT WIND SHEAR TO DEVELOP AS SURFACE WINDS REMAIN LIGHT FROM THE NORTHEAST...BUT WINDS INCREASE SIGNIFICANTLY ALOFT LATER TODAY AND TONIGHT. LONG TERM...IFR TO MVFR CONDITIONS THURSDAY NIGHT WILL IMPROVE TO VFR FRIDAY. VFR CONDITIONS EXPECTED SATURDAY AND SUNDAY...EXCEPT IN THE MOUNTAINS WHERE MVFR CONDITIONS ARE POSSIBLE IN SNOW SHOWERS. && .MARINE... SHORT TERM...SCA CONDITIONS EXPECTED THURSDAY NIGHT AND FRIDAY AND AGAIN SUNDAY AND MONDAY LONG TERM...GALE WARNINGS ARE NOW IN EFFECT FOR ALL OF OUR WATERS. WINDS WILL INCREASE OUT OF THE SOUTH TONIGHT WITH BUILDING SEAS. && .HYDROLOGY... RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE EXPECTED THROUGH THURSDAY AFTER SOME SNOW...SLEET...AND FREEZING RAIN. LOCALIZED AMOUNTS OF 3 TO 3.5 INCHES WILL BE POSSIBLE ON THE EAST-SOUTHEAST FACING SLOPES OF THE WHITES AND MAINE FOOTHILLS. THIS MAY POSE SOME MINOR FLOODING PROBLEMS FOR POOR DRAINAGE AREAS AS WELL AS SIGNIFICANT RISES FOR THE SACO...PEMI...AND SWIFT RIVERS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MEZ018- 019. WINTER WEATHER ADVISORY UNTIL 5 AM EST THURSDAY FOR MEZ007>009- 012>014-020>022. WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR MEZ023>028. NH...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NHZ005>011-015. WINTER WEATHER ADVISORY UNTIL 5 AM EST THURSDAY FOR NHZ001>004. WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR NHZ012>014. MARINE...GALE WARNING FROM 11 PM THIS EVENING TO 1 PM EST THURSDAY FOR ANZ151-153. GALE WARNING FROM 11 PM THIS EVENING TO 7 PM EST THURSDAY FOR ANZ150-152-154. && $$ SYNOPSIS... NEAR TERM...CANNON SHORT TERM...CANNON LONG TERM...JENSENIUS AVIATION...CANNON/JENSENIUS MARINE...CANNON/JENSENIUS HYDROLOGY...CANNON
AREA FORECAST DISCUSSION
NWS GRAY ME
531 AM EST WED FEB 24 2016 .SYNOPSIS... THE SNOW WILL CHANGE TO A WINTRY MIX TODAY AS WARMER AIR BEGINS TO MOVE INTO THE REGION ALOFT AHEAD OF A MUCH STRONGER LOW PRESSURE SYSTEM. THIS LOW WILL MOVE WEST OF THE REGION TONIGHT AND THURSDAY...BRINGING A ROUND OF HEAVY RAINFALL TO THE REGION AS TEMPERATURES WARM WELL ABOVE SEASONAL NORMS. MUCH COOLER AIR WILL FLOW BACK INTO THE REGION TO END THE WEEK. ANOTHER LOW PRESSURE SYSTEM WILL PASS NORTH OF THE REGION SUNDAY NIGHT AND MONDAY AND WILL DRAG A COLD FRONT ACROSS THE REGION LATE MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATE... COLD AIR HOLDING IN TOUGH WITH A NORTHERLY COMPONENT TO THE WIND FIELDS EVEN ALONG THE COAST. HAVE EXPANDED TO INCLUDE A BRIEF WINTER WEATHER ADVISORY FOR THE COASTLINE AS WELL...WITH TEMPERATURES RUNNING IN THE UPPER 20S TO LOWER 30S AND THE PRECIPITATION BEGINNING TO CHANGE OVER TO FREEZING RAIN IN SPOTS. THE LATEST HRRR IS BEGINNING TO HAVE A GOOD HANDLE ON THIS DELAY IN THE BOUNDRY LAYER/SURFACE WARMING. THIS NEW ADVISORY WILL BE IN AFFECT UNTIL 10 AM. HAVE ALSO EXPANDED THE ADVISORY UNTIL 10 AM ACROSS INTERIOR ROCKINGHAM COUNTY AS WELL. PREV DISC... A VERY COMPLEX SCENARIO CONTINUES AS COLD ARCTIC AIR REMAINS IN PLACE IN A SHALLOW LAYER NEAR THE SURFACE OVER MAIND AND NEW HAMPSHIRE. HOWEVER...VERY WARM AIR CONTINUES TO ENTER THE REGION ALOFT. PRECIPITATION EARLY THIS MORNING ASSOCIATED WITH THE FIRST INITIAL SHORT WAVE REMAINS IN THE FORM OF SNOW FOR MOST AREAS. EXPECT THE PRECIP TO CHANGE TO RAIN TODAY ALONG THE COAST AS A STRONG EASTERLY FLOW CONTINUES NEAR/ALONG THE COASTAL FRONT. FURTHER INLAND...THE PRECIP WILL CHANGE TO SLEET AND FREEZING RAIN AFTER A FEW INCHES OF SNOW ACCUMULATES. ELEVATIONS AROUND 1500 FEET MAY HOLD ONTO THE FREEZING RAIN THE LONGEST WITH A FEW LOCATIONS PICKING UP CLOSE TO A HALF INCH OF ICE ACCRETION. MODELS ARE IN RELATIVELY GOOD AGREEMENT WITH THE FEATURES IN THIS COMPLEX SYSTEM WITH THE MODEL ENSEMBLES PLACING THE MAIN UPPER LEVEL LOW PRESSURE SYSTEM MOVING QUICKLY TO THE NORTH FROM THE SOUTHERN OHIO VALLEY BY LATER TODAY. MESOSCALE MODELS SUGGEST THERE COULD BE A LULL IN THE PRECIPITATION BY THE TIME WE REACH THE MIDDAY HOURS. THIS MAY ALLOW THE PRECIP TO CHANGE TO A FREEZING DRIZZLE OR DRIZZLE IN SOME AREAS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... MAIN...LARGE SCALE SYNOPTIC SYSTEM APPROACHES TONIGHT AS CYCLOGENESIS CONTINUES AS THE SURFACE LOW REACHES UPSTATE NEW YORK. A STRONG LOW LEVEL JET WILL ADVECT WARM...MOIST AIR. HIGH PWAT AND POLEWARD WIND VALUES CONTINUE TO BE FORECAST IN A HIGHLY ANOMALOUS EVENT. EXPECT THE RAIN TO BECOME HEAVY AFTER MIDNIGHT. THE ATMOSPHERE WILL REMAIN UNSTABLE WITH CONVECTION FORMING LATE AT NIGHT WITH SCATTERED THUNDERSTORMS CONTINUING INTO EARLY THURSDAY. LOCALLY HEAVY RAIN WILL CONTINUE EARLY THURSDAY MORNING AHEAD OF THE STRONG APPROACHING COLD FRONT. A DRY SLOT WILL ALLOW FOR THE PRECIP TO BECOME LIGHT DURING THE LATE MORNING AND AFTERNOON HOURS. MODELS ARE NOW IN FAIRLY GOOD AGREEMENT WITH THE TIMING OF THE PASSAGE OF THE COLD FRONT. WINDS WILL INCREASE OUT OF THE SOUTH LATER TONIGHT AND EARLY THURSDAY MORNING. WIND GUSTS TO 50 MPH ARE POSSIBLE ALONG THE COAST. THESE HIGH WINDS WILL ARRIVE ON AN INCREASING MIXING LAYER AND STRONG LOW LEVEL JET. THIS WARM AIR ADVECTION WILL ALLOW READINGS TO SOAR INTO THE 50S IN SOME AREAS. THE RECORD HIGH IN PORTLAND FOR THURSDAY IS 51 WHICH WILL LIKELY BE BROKEN. THE PREVIOUS RECORD WAS SET IN 1984 AND 1985. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... A COLD FRONT WILL CROSS THE REGION THURSDAY NIGHT BRINGING THE RETURN OF COLDER TEMPERATURES FRIDAY INTO THE WEEKEND. MODELS NOT IN GOOD AGREEMENT ON THE MAGNITUDE OF THE COLDER AIR WITH THE NAM MOS QUITE A BIT COLDER THAN THE GFS. HAVE USED A BLEND WHICH SEEMS MORE REASONABLE. THE FRONT COULD BE ACCOMPANIED BY SOME RAIN SHOWERS WHICH EVENTUALLY WILL CHANGE TO SNOW SHOWERS AS THE COLDER AIR MOVES INTO THE REGION THURSDAY NIGHT. A RIDGE OF HIGH PRESSURE WILL BUILD INTO THE AREA SATURDAY THEN WILL MOVE EAST OF THE AREA SATURDAY NIGHT AND SUNDAY. WARM ADVECTION ON THE BACK SIDE OF THE RIDGE WILL BRING MORE CLOUDS INTO THE REGION SUNDAY AS LOW PRESSURE APPROACHES FROM THE WEST. THIS WILL BRING INCREASING CHANCES FOR PRECIPITATION, FIRST AS SNOW SHOWERS SUNDAY NIGHT, THEN RAIN SHOWERS MONDAY AS THE LOW MOVES NORTH OF THE AREA. A COLD FRONT IS EXPECTED TO CROSS THE AREA LATE MONDAY BRINGING A RETURN OF COLDER AIR AND WITH THE POSSIBILITY THAT ANY RAIN SHOWERS MAY CHANGE BACK TO SNOW SHOWERS. AHEAD OF THE FRONT MONDAY, ESPECIALLY SOUTHERN AND COASTAL AREAS WILL SEE ANOTHER WARM DAY TO FINISH OUT THE MONTH OF FEBRUARY. COLDER AIR WILL RETURN TO THE REGION FOR TUESDAY AND WEDNESDAY. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM...MOST AREAS WILL DETEORATE TO LIFR CONDITIONS. MIXED PRECIPITATION WITH ICING EXPECTED TODAY INTO TONIGHT. EXPECT WIND SHEAR TO DEVELOP AS SURFACE WINDS REMAIN LIGHT FROM THE NORTHEAST...BUT WINDS INCREASE SIGNIFICANTLY ALOFT LATER TODAY AND TONIGHT. LONG TERM...IFR TO MVFR CONDITIONS THURSDAY NIGHT WILL IMPROVE TO VFR FRIDAY. VFR CONDITIONS EXPECTED SATURDAY AND SUNDAY...EXCEPT IN THE MOUNTAINS WHERE MVFR CONDITIONS ARE POSSIBLE IN SNOW SHOWERS. && .MARINE... SHORT TERM...SCA CONDITIONS EXPECTED THURSDAY NIGHT AND FRIDAY AND AGAIN SUNDAY AND MONDAY LONG TERM...GALE WARNINGS ARE NOW IN EFFECT FOR ALL OF OUR WATERS. WINDS WILL INCREASE OUT OF THE SOUTH TONIGHT WITH BUILDING SEAS. && .HYDROLOGY... RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE EXPECTED THROUGH THURSDAY AFTER SOME SNOW...SLEET...AND FREEZING RAIN. LOCALIZED AMOUNTS OF 3 TO 3.5 INCHES WILL BE POSSIBLE ON THE EAST-SOUTHEAST FACING SLOPES OF THE WHITES AND MAINE FOOTHILLS. THIS MAY POSE SOME MINOR FLOODING PROBLEMS FOR POOR DRAINAGE AREAS AS WELL AS SIGNIFICANT RISES FOR THE SACO...PEMI...AND SWIFT RIVERS. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MEZ018- 019. WINTER WEATHER ADVISORY UNTIL 5 AM EST THURSDAY FOR MEZ007>009- 012>014-020>022. WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR MEZ023>028. NH...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NHZ005>011-015. WINTER WEATHER ADVISORY UNTIL 5 AM EST THURSDAY FOR NHZ001>004. WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR NHZ012>014. MARINE...GALE WARNING FROM 11 PM THIS EVENING TO 1 PM EST THURSDAY FOR ANZ151-153. GALE WARNING FROM 11 PM THIS EVENING TO 7 PM EST THURSDAY FOR ANZ150-152-154. && $$ SYNOPSIS... NEAR TERM...CANNON SHORT TERM...CANNON LONG TERM...JENSENIUS AVIATION...CANNON/JENSENIUS MARINE...CANNON/JENSENIUS HYDROLOGY...CANNON
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
ISSUED BY NATIONAL WEATHER SERVICE CHARLESTON WV 656 PM EST THU FEB 25 2016 .SYNOPSIS... COLDER TEMPERATURES WITH SNOW SHOWERS TAPERING OFF LATER TONIGHT. HIGH PRESSURE AND SEASONAL CONDITIONS RETURN FOR THE WEEKEND. && .NEAR TERM /THROUGH FRIDAY/... UPPER TROUGH IS EXPECTED TO PIVOT ACROSS THE LOWER GREAT LAKES WITH A REINFORCING SHORTWAVE BRINGING ADDITIONAL SNOW SHOWERS THROUGH THIS EVENING AND OVERNIGHT. WHILE SNOW HAS HAD DIFFICULTY ACCUMULATING OUTSIDE OF THE RIDGES DUE TO WARM SURFACE TEMPERATURES FROM THE LAST FEW DAYS AND SOUTHWEST FLOW AT THE SURFACE...A NORTHWEST WIND SHIFT...STRENGTHENING COLD ADVECTION AND LOSS OF WHAT INSOLATION WE HAD SHOULD ALLOW FOR ADDITIONAL SNOWFALL TO STICK. DEEP MOISTURE BELOW THE INVERSION IN THE DENDRITIC GROWTH ZONE...FAVORABLE WIND DIRECTION FOR LAKE ENHANCEMENT...AND OMEGA PLACEMENT ARE ALL FACTORS TO SUPPORT THE ONGOING WINTER WEATHER ADVISORY FOR THE HIGHER TERRAIN IN WV...MD...AND PA. HAVE BUMPED UP THE SNOW AMOUNTS IN THESE AREAS BASED ON THE SYNOPTIC AND UPSLOPE SUPPORT WHICH WILL GET OUR SNOW AMOUNTS OVER 6 INCHES IN SOME SPOTS. IN ADDITION TO THE SNOW...STRONG MIXING IN THE HAS PRODUCED GUSTS NEAR 40MPH IN THE RIDGES. WHILE THESE STRONGER GUSTS SHOULD ONLY LAST 6 HOURS OR SO...HAVE EMPHASIZED THE NEAR- ADVISORY WIND GUSTS IN THE UPDATED WSW THROUGH THIS EVENING. OUTSIDE OF THE HIGH TERRAIN THERE IS A WINDOW LATE THIS AFTERNOON/EVENING WHERE LOW LEVEL INSTABILITY APPEARS TO BE MAXIMIZED COINCIDING WITH THE SHORTWAVE PASSAGE. THIS MAY BE ENOUGH TO INVIGORATE SOME SNOW SQUALLS...AS IS EMPHASIZED IN THE HRRR AND THE RUC IN THE SNOW SQUALL PARAMETER. WILL CONTINUE TO MONITOR FOR THESE CONCERNS THROUGH THE AFTERNOON BEFORE SUBSIDENCE BUILDS AND INVERSION HEIGHTS BEGIN TO LOWER. && .SHORT TERM /FRIDAY NIGHT/... SNOW SHOWERS WILL DIMINISH FRIDAY AS LOW LEVELS DRY OUT AND INVERSIONS DROP BUT THE LATEST MODEL DATA DOES SUGGEST A DUAL-LAKE BAND MAY PROLONG SNOW SHOWER ACTIVITY IN OUR COUNTIES NORTH OF I-80 THROUGH FRIDAY MORNING. HAVE NOT ADJUSTED THE TIMING OF THE CURRENT ADVISORY IN THOSE COUNTIES DUE TO UNCERTAINTY AT THIS TIME BUT AN ADDITIONAL INCH MAY BE POSSIBLE IF A BAND PERSISTS. SURFACE RIDGING WILL BUILD IN LATER FRIDAY FOR THE WEEKEND THOUGH COLD ADVECTION AND CLOUD COVER SHOULD KEEP TEMPERATURES BELOW NORMAL FRIDAY AND FRIDAY NIGHT. TEMPERATURES WILL MODERATE LATE SATURDAY...WITH HIGHS FORECAST ABOVE SEASONAL AVERAGES BY SUNDAY AS SOUTHWEST FLOW RETURNS AHEAD OF THE NEXT FAST-MOVING SYSTEM FOR THE START OF THE WEEK. && .LONG TERM /SATURDAY THROUGH THURSDAY/... THE ECMWF AND GFS HAVE DECENT AGREEMENT EXCEPT FOR SOME TIMING DIFFERENCES WITH LOW PRESSURE AND A COLD FRONT CROSSING THE REGION SUNDAY NIGHT INTO MONDAY MORNING. APPEARS THAT LOCATIONS SOUTH OF PITTSBURGH WOULD RECEIVE RAIN...WHILE LOCATIONS NORTH OF PITTSBURGH WOULD HAVE SNOW MIX IN FOR A PERIOD OF TIME. ANOTHER SYSTEM MOVES IN FOR THE MIDDLE OF THE WEEK. WITH MODELS LACKING RUN-TO-RUN CONSISTENCY FOR THE SECOND SYSTEM...HAVE MADE RELATIVELY SMALL CHANGES TO THIS PORTION OF THE FORECAST. TEMPERATURES SHOULD BE SLIGHTLY ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... 00Z FRIDAY THRU 00Z SATURDAY... WIDESPREAD MVFR/IFR RESTRICTIONS ARE EXPECTED IN SNOW SHOWERS THIS EVENING...IFR/LIFR VISIBILITIES CANNOT BE RULED OUT IN HEAVIER SNOW SHOWERS. AFTER MIDNIGHT...BULK OF THE SNOWFALL SHOULD REMAIN CONTAINED TO FKL/DUJ TERMINALS. EVEN WITH SNOW SHOWER COVERAGE DIMINISHING...EXPECT THAT MVFR CIGS SHOULD REMAIN AT ALL SITES THROUGH 14Z FRIDAY. WINDS SHOULD BE OUT OF THE WEST- NORTHWEST UP TO 20-30 KT...WITH GUSTS DIMINISHING OVERNIGHT. AFTER 14Z...SLOWLY IMPROVING TO VFR CEILINGS FROM NORTHWEST TO SOUTHEAST. .OUTLOOK.../AFTER 00Z SATURDAY/... RESTRICTIONS ARE PSBL WITH A MON COLD FRONT. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...WINTER WEATHER ADVISORY UNTIL 7 AM EST FRIDAY FOR MDZ001. OH...NONE. PA...WINTER WEATHER ADVISORY UNTIL 5 AM EST FRIDAY FOR PAZ007-008. WINTER WEATHER ADVISORY UNTIL 7 AM EST FRIDAY FOR PAZ074-076. WV...WINTER WEATHER ADVISORY UNTIL 7 AM EST FRIDAY FOR WVZ510>514. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
406 AM EST WED FEB 24 2016 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 410 PM EST TUE FEB 23 2016 WV IMAGERY AND RAP ANALYSIS INDICATED NRN STREAM AFFECTING THE NRN LAKES DOMINATED BY A MID/UPPER LEVEL LOW N OF HUDSON BAY AND A RIDGE OVER WRN CANADA. 700-500 MB QVECTOR CONV ASSOCIATED WITH A SHORTWAVE TROUGH FROM NW ONTARIO INTO NRN MN SUPPORTED AREAS OF SNOW FROM NE MN INTO NW WI TO IWD AND INCREASING CLOUDS THROUGH WRN UPPER MI. OTHERWISE...SUNSHINE OVER THE CNTRL AND EAST ALONG WITH SW FLOW WAA HAS HELPED PUSH TEMPS INTO THE MID 30S. TONIGHT...THE MODELS SUGGEST THAT AS THE UPSTREAM SHRTWV DIGS TO THE SE...THE FORCING WILL WEAKEN THIS EVENING AS THE AREA OF LIGHT SNOW MOVES INTO THE WRN CWA. SO...ONLY CHANCE POPS MENTIONED WITH ANY ACCUMULATIONS OF A HALF INCH OR LESS. ADDITIONAL LIGHT SNOW SHOWERS WILL BE POSSIBLE FROM IWD TO CMX AS THE SFC TROUGH MOVES THROUGH OVERNIGHT. EVEN WITH WINDS VEERING NRLY...850 MB TEMPS TO AROUND -7C WILL PROVIDE LITTLE ADDITIONAL INSTABILITY FOR LES OR LAKE ENHANCED SNOW. WEDNESDAY...THE AREA WILL FALL UNDER THE INFLUENCE OF THE CIRCULATION AROUND DEEPENING LOW PRES MOVING TOWARD THE LOWER LAKES. INCREASING NRLY FLOW WITH 850 MB TEMPS FALLING TO AROUND -10C ALONG WITH A BAND OF LINGERING 925-850 MB MOISTURE...WILL SUPPORT SCT LIGHT SNOW SHOWERS INTO LOCATIONS FAVORED BY N TO NE FLOW OVER THE WEST HALF. INVERSION HEIGHTS ARUOND 4K FT AND MARGINAL INSTABILITY SHOULD LIMIT ANY ACCUMULATIONS TO LESS THAN AN INCH. TEMPS WILL REMAIN SLIGHTLY ABOVE NORMAL WITH HIGHS IN THE LOWER TO MID 30S. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 359 PM EST TUE FEB 23 2016 WEDNESDAY NIGHT THROUGH THURSDAY...A STRONG LOW PRESSURE SYSTEM WILL CONTINUE TO INTENSIFY AND SLIDE NORTHWARD TO THE SOUTHERN GREAT LAKES WEDNESDAY NIGHT INTO THURSDAY AS ANOTHER LOW PRESSURE SYSTEM OVER THE NORTHERN PLAINS MERGES INTO IT. COLDER AIR IS EXPECTED TO BE DRAWN INTO THE UPPER GREAT LAKE REGION AS MOISTURE BEGINS TO INCREASE. 850MB TEMPERATURES ARE EXPECTED TO DROP TO THE -12C TO -15C RANGE WEDNESDAY NIGHT THROUGH THURSDAY. THIS ALONG WITH CONTINUED NORTH TO NORTH-NORTHWESTERLY FLOW AND A LITTLE DEEPER MOISTURE OVER THE WEST HALF WILL HELP TO INCREASE LAKE EFFECT SNOW CHANCES...AGAIN FOR NORTH TO NORTH-NORTHWEST WIND SNOW BELTS. INVERSION HEIGHT PROGGED TO BE AT OR BELOW 4KFT SHOULD KEEP LAKE EFFECT SNOW TOTALS FAIRLY LIGHT THROUGH THIS TIME PERIOD. OVER THE EAST HALF...THE LES POTENTIAL DEPENDS LARGELY ON THE EXACT TRACK OF THE LOW...WHICH LOOKS LIKE IT WILL BE FAR ENOUGH EAST TO GIVE LITTLE IF ANY CHANCE OF LAKE EFFECT OVER THE EAST HALF. FREEZING DRIZZLE IS POSSIBLE OVER THE EAST HALF...DUE TO THE LACK OF ICE CRYSTALS IN THE LAYER...BUT DID NOT MENTION AT THIS POINT AS IT LOOKS LIKE LOWER LEVEL DRY AIR MAY KEEP THIS FROM BEING A MAJOR ISSUE. IT WILL BE QUITE WINDY DURING THE DAY OVER THE EAST HALF AS THE AREA WILL BE IN CLOSE PROXIMITY TO THE TIGHTER PRESSURE GRADIENT ASSOCIATED WITH THE STRONG LOW PRESSURE SYSTEM. COULD SEE GALE GUSTS OVER EASTERN LAKE SUPERIOR AND OVER NORTHERN LAKE MI. WIND GUSTS OVER THE EAST HALF OF THE U.P. COULD GUST TO 25 TO 35 MPH THROUGH THIS TIME PERIOD. THURSDAY NIGHT THROUGH FRIDAY...THE STRONG LOW PRESSURE SYSTEM WILL CONTINUE NORTHEASTWARD INTO NORTHEAST QUEBEC BY FRIDAY AFTERNOON. BEING ON THE WESTERN EDGE OF THE DEPARTING LOW ALONG WITH THE APPROACH OF A 500MB SHORTWAVE...LIGHT LAKE EFFECT SNOW POTENTIAL WILL CONTINUE THURSDAY NIGHT OVER NORTHWEST WIND FAVORED LOCATIONS. THE MORE CONCENTRATED SNOW WILL OCCUR AS THE SHORTWAVE SLIDES THROUGH...IN THE EVENING OVER THE WEST HALF AND OVERNIGHT OVER THE EAST HALF AS INVERSION HEIGHTS BRIEFLY JUMP TO AROUND 5KFT TO 6KFT. 850MB TEMPERATURES WILL THEN BEGIN TO MODERATE LATE FRIDAY AS A SURFACE RIDGE SLIDES IN AND 500MB HEIGHTS INCREASE. AGAIN...THIS SHOULD BE BRIEF ENOUGH THAT TOTALS SHOULD REMAIN FAIRLY LIGHT. 850MB TEMPERATURES ARE PROGGED TO INCREASE TO AROUND -10C THROUGH THE DAY FRIDAY AHEAD OF THE NEXT APPROACHING LOW PRESSURE SYSTEM SLIDING ACROSS CENTRAL CANADA. WINDS ARE PROGGED TO BECOME MORE WEST TO WEST- SOUTHWEST BY FRIDAY AFTERNOON...WHICH WILL END THE LIGHT LAKE EFFECT POTENTIAL FOR ALL AREAS EXCEPT THE KEWEENAW PENINSULA. FRIDAY NIGHT THROUGH SUNDAY NIGHT...A LOW PRESSURE SYSTEM OVER CENTRAL CANADA IS PROGGED TO SLIDE FROM EAST-CENTRAL MANITOBA TO NEAR JAMES BAY SATURDAY AFTERNOON TO NORTHEAST QUEBEC BY SUNDAY AFTERNOON. THIS WILL ALLOW A COLD FRONT TO SLIDE ACROSS THE UPPER GREAT LAKES REGION LATE SATURDAY NIGHT INTO SUNDAY MORNING. 850MB TEMPERATURES AND WEST TO WEST-SOUTHWEST WINDS WELL IN ADVANCE OF THE FRONT WILL KEEP LAKE EFFECT SNOW POTENTIAL FAIRLY LOW. ALONG AND IMMEDIATELY AHEAD OF THE COLD FRONT INCREASED FORCING WILL ALLOW SYSTEM SNOW TO DEVELOP AND SLIDE THROUGH THE AREA LATE SATURDAY NIGHT INTO SUNDAY MORNING AS SHOWN BY OVERLAYING DEEP LAYER QCONV ALONG WITH 1000-500MB RH. QPF LOOKS TO BE FAIRLY LIGHT THROUGH FOR THE FRIDAY NIGHT SATURDAY MORNING TIME PERIOD WITH ONLY AROUND 0.10 INCHES PAINTED OUT ALONG THE FRONT. ALOFT 500MB TROUGHING WILL BE INTENSIFIED ACROSS THE AREA AS THE LOW DEPARTS TO THE EAST OF THE AREA ALLOWING COLDER TEMPERATURES TO SLIDE INTO THE UPPER GREAT LAKES REGION ON THE BACKSIDE OF THE COLD FRONT SUNDAY AFTERNOON AND NIGHT. LATE SATURDAY NIGHT THROUGH SUNDAY 850MB TEMPERATURES ARE PROGGED TO QUICKLY FALL INTO THE -15C TO -20C RANGE. THIS WILL BE FAVORABLE FOR LAKE EFFECT SNOW...ESPECIALLY FOR NORTH TO NORTHWEST WIND FAVORED SNOW BELTS. THERE ARE STILL SOME DIFFERENCES IN THE INTENSITY AND POSITION OF THE SURFACE LOW AND COLD FRONT POSITION DURING THIS TIME PERIOD SO THE EXACT TIMING AND LOCATIONS FOR THE STEADIER LAKE EFFECT WILL NEED TO BE FINE-TUNED AS MODELS TREND TOWARD A SIMILAR SOLUTION. MODERATE LAKE EFFECT SNOW CONTINUES TO LOOK AS THOUGH IT WILL OCCUR...BUT IT WOULD LIKELY BE MORE FOCUSED DURING THE SUNDAY AFTERNOON AND SUNDAY NIGHT TIME PERIOD FOR NORTH TO NORTHWEST WIND LOCATIONS. THE GRADIENT LOOKS TO BE WEAKER ACROSS THE AREA FROM THIS SYSTEM...KEEPING WINDS LIGHTER THAN IT APPEARED A COUPLE DAYS AGO. THERE WILL STILL BE BLOWING SNOW SUNDAY AFTERNOON AND SUNDAY NIGHT BUT IT DOES NOT LOOK AS EXTREME AS EARLIER MODELS HAD SUGGESTED. MONDAY THROUGH TUESDAY...A LOW PRESSURE SYSTEM WILL SLIDE FROM THE MID MISSISSIPPI VALLEY TO THE NEW ENGLAND STATES THROUGH THIS TIME PERIOD. IT MAY BRUSH THE U.P. LATE SUNDAY NIGHT INTO EARLY MONDAY MORNING BUT MODELS ARE STILL DIFFERING ON THE SOLUTION. EC IS FARTHER NORTH AND GFS IS FARTHER SOUTH. ANOTHER SHOT OF COLDER AIR LOOKS LIKE IT WILL WORK ITS WAY DOWN INTO THE AREA MONDAY AND MONDAY NIGHT WITH ANOTHER SHOT OF LAKE EFFECT SNOW FOR WEST TO WEST NORTHWEST LOCATIONS. WILL GO WITH A CONSENSUS OF THE MODELS FOR NOW AS THE MODELS DIFFER ENOUGH TO LIMIT CONFIDENCE ON PINNING DOWN SNOW PROBABILITY FOR SPECIFIC WIND DIRECTIONS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1030 PM EST TUE FEB 23 2016 MVFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE PERIOD AT ALL SITES. THERE WILL HOWEVER BE BRIEF TIMES OF IFR CONDITIONS AT ALL SITES AS WELL IN LIGHT SNOW OR UPSLOPE FLOW WITH THE BEST CHANCE OF SEEING IFR AT KIWD AND KSAW LATE TONIGHT INTO WED MORNING...WED AFTERNOON AT KCMX. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 406 AM EST WED FEB 24 2016 LOW PRESSURE OVER W KY WILL SHIFT ACROSS THE LOWER GREAT LAKES AT TONIGHT...BEFORE EXITING INTO QUEBEC ON THURSDAY. THIS WILL BE WHILE HIGH PRESSURE ACROSS ONTARIO EXITS INTO N QUEBEC. THE RESULT WILL BE N-NE GALES OF 35-40KTS OVER MAINLY E LAKE SUPERIOR LATE THIS EVENING THROUGH THURSDAY. LOOK FOR WINDS TO SLOWLY DIMINISH AS HIGH PRESSURE ACROSS THE PLAINS STATES THURSDAY BUILDS A RIDGE ACROSS THE UPPER GREAT LAKES THURSDAY NIGHT-FRIDAY...AS THE AREA OF HIGH PRESSURE SINKS TO THE GULF COAST FOR FRIDAY-SATURDAY. THE RIDGE OVER THE UPPER GREAT LAKES WILL BE REPLACED BY A TROUGH FRIDAY NIGHT-SATURDAY...WHILE THE PARENT LOW CROSSES N ONTARIO. SW GUSTS COULD NEAR 30KTS FRIDAY NIGHT-EARLY SATURDAY. A WEAK RIDGE SHOULD BRIEFLY BUILD ACROSS LAKE SUPERIOR SATURDAY NIGHT...BEFORE THE NEXT LOW OVER THE CENTRAL PLAINS NEARS LAKE MICHIGAN ON SUNDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING FROM MIDNIGHT TONIGHT TO 7 PM EST THURSDAY FOR LSZ266-267. LAKE MICHIGAN... GALE WARNING FROM 10 PM THIS EVENING TO 7 PM EST THURSDAY FOR LMZ248-250. && $$ SHORT TERM...JLB LONG TERM...KEC AVIATION...07 MARINE...KF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1151 PM EST TUE FEB 23 2016 .AVIATION... NORTHEAST WINDS WILL SLOWLY INCREASE DURING THE MORNING WITH THE APPROACH OF THE WINTER STORM SYSTEM...WITH GUSTS LIKELY TOPPING 20 KNOTS TOWARD DAYBREAK. CIGS ARE EXPECTED TO DROP QUICKLY AS PRECIP OVERSPREADS SE MI FROM SOUTH TO NORTH BETWEEN 11Z AND 15Z WED MORNING. ATTM...PRECIP TYPE IS EXPECTED TO BE A MIX OF SNOW AND RAIN WED MORNING AROUND DETROIT...AND MAINLY SNOW AT PTK/FNT/MBS. CONDITIONS WILL DETERIORATE INTO WEDNESDAY AFTERNOON AS BOTH SNOWFALL INTENSITY AND NORTHEAST WINDS INCREASE. DAYTIME SNOW ACCUMULATIONS ARE EXPECTED TO RANGE FROM 3 TO 5 INCHES AT PTK/FNT/MBS. THE SNOWFALL WILL BE HEAVY AND WET. FOR DTW...LATEST GUIDANCE SUGGESTS PRECIP ONSET BETWEEN AROUND 11Z...LIKELY BEING A MIX OF RAIN AND SNOW. THERMAL PROFILES AT METRO WILL BE RIGHT ON THE BORDER BETWEEN RAIN AND SNOW INTO THE AFTERNOON. THIS LEADS TO A HIGH DEGREE OF UNCERTAINTY AS TO WHETHER ANY SNOW ACCUMULATIONS WILL OCCUR BY MID WED AFTERNOON. IF THE CHANGE OVER TO SNOW OCCURS MORE QUICKLY...AN INCH OR TWO OF ACCUMULATION DURING THE LATE MORNING AND EARLY AFTERNOON IS POSSIBLE. //DTW THRESHOLD PROBABILITIES... * HIGH IN CEILINGS BELOW 5000 THROUGH THE TAF PERIOD. * LOW IN TIMING THE CHANGE OVER FROM RAIN TO SNOW ON WEDNESDAY. && .PREV DISCUSSION...ISSUED 957 PM EST TUE FEB 23 2016 UPDATE... NO MAJOR FORECAST CHANGES ARE PLANNED AT THIS TIME. ANY ADJUSTMENTS WILL AWAIT THE ANALYSIS OF THE FULL 00Z MODEL SUITE. THE LATEST SATELLITE LOOP NOW SHOWS THE UPPER LOW CHURNING OVER THE SOUTHERN MISSISSIPPI VALLEY...WITH SIGNS OF STRENGTHENING MID LEVEL DEFORMATION ACROSS NORTHERN ARKANSAS AND SOUTHERN MISSOURI. THE 02Z SURFACE ANALYSIS SHOWS A 995MB SFC LOW OVER NRN MISSISSIPPI. THE LAST FEW SFC ANALYSES AND RECENT SFC PRESSURE CHANGE SUGGEST THE SFC LOW WILL LIFT INTO WRN TENNESSEE/WRN KENTUCKY OVERNIGHT. SUGGESTING THE MORNING GFS RUN MAY INDEED BE A LITTLE TOO FAR WEST...YET ALSO RAISING SOME CONCERNS THE ECMWF MAY HAVE BEEN A BIT TOO FAR EAST. THIS DOES SUPPORT THE IDEA THAT THE SERN SECTIONS OF THE FORECAST AREA WILL FLUCTUATE FROM RAIN TO SNOW AND BACK AT TIMES...WITH THE FAR SOUTHEAST /MONROE TO DOWNTOWN DETROIT/ POSSIBLY REMAINING ALL RAIN INTO THE EVENING BEFORE FULLY CHANGING OVER TO SNOW. LATER FORECAST SHIFTS WILL CONTINUE TO EVALUATE THE THERMAL PROFILE AS THIS WILL HAVE BIG IMPLICATIONS AS TO SNOWFALL AMOUNTS /ESPECIALLY SOUTHEAST OF AN ANN ARBOR TO PORT HURON LINE/. FARTHER NORTH AND WEST...PREDOMINATE PRECIP TYPE AS SNOW AND STRONG MID LEVEL DEFORMATION WITH TREMENDOUS MOISTURE TRANSPORT WILL SUPPORT SOLID WARNING CRITERIA SNOWFALL. AS FAR AS THE EVENING UPDATE...THE RECENT HRRR AND 00Z NAM ARE PICKING UP ON THE DEGREE OF DRY AIR /NOTED ON THE 00Z DTX SOUNDING/. THIS WILL SUPPORT BACKING OFF THE ONSET OF PRECIP ACROSS THE NORTHERN DETROIT SUBURBS BY A COUPLE HOURS. THE LEAD EDGE OF THE PRECIP IS EXPECTED TO REACH DETROIT/ANN ARBOR AROUND 11Z...THEN LIFT INTO FLINT AND PORT HURON AROUND 13Z. PREV DISCUSSION...ISSUED 347 PM EST TUE FEB 23 2016 DISCUSSION... A VERY CHALLENGING FORECAST REMAINS FOR SOUTHEAST MICHIGAN WITH HIGHLY SENSITIVE THERMAL FIELDS...AS THE INTERACTION OF THREE KEY UPPER LEVEL PLAYERS TAKES PLACE OVER THE NEXT 24-48 HOURS...WITH SHARP LOW LEVEL BAROCLINIC ZONE EXPECTED TO WORK THROUGH THE CWA...AS EXCELLENT MOISTURE TRANSPORT OCCURS IN MID LEVELS. SHORTWAVE UPPER LEVEL TROUGH TRACKING THROUGH MINNESOTA EXTENDING BACK INTO THE CENTRAL PLAINS TO CONTINUE TO DROP SOUTH AND FORCE THE LARGE UPPER LEVEL LOW OVER TEXAS TO THE NORTHEAST. THE CIRCULATION IS QUICKLY TIGHTENING UP AND WILL ALLOW FOR RAPID DEEPENING OF THE LOW PRESSURE THIS EVENING OVER WESTERN GULF STATES. THE BIG ISSUE IS THE MID/UPPER LEVEL CIRCULATION OVER THE MID MISSISSIPPI RIVER VALLEY AT 12Z WEDNESDAY QUICKLY UNRAVELS AND EXPANDS OUTWARD...WITH THE EXCELLENT FORCING PROVIDED BY THE UPPER LEVEL PV FILAMENT ADVANCING NORTH...ARRIVING WEDNESDAY MORNING...WITH PW VALUES PUSHING TOWARD 0.75 INCHES...AND 700 MB SPECIFIC HUMIDITY RUNNING AROUND 4 G/KG...AND EVEN MAYBE APPROACHING 5 G/KG DOWNRIVER BY EARLY AFTERNOON. WITH THAT MOISTURE COMES WARMTH...AND WILL BE TOWING THE LINE WITH THE 0 C ISOTHERM ACROSS A VERY DEEP LAYER. THE GFS AND NAM MODEL DIFFERENCES ARE VERY PRONOUNCED...AS 925-850 MB WET BULB TEMPS OF THE GFS ARE A GOOD 5 DEGREES C WARMER THAN THE NAM OVER WAYNE COUNTY BY WEDNESDAY AFTERNOON. THE OPERATIONAL GFS REMAINS A BIT OF A WESTERN OUTLIER WITH THE SURFACE LOW TRACK COMPARED TO ITS ENSEMBLE MEMBERS...AND WITH THE GEM MORE IN LINE WITH THE NAM...FORECAST WAS SKEWED ON THE COLDER SIDE...AS THE 12Z EURO HAS COME IN LINE WITH ITS 00Z RUN. THE HUGE DIVERGENCE BETWEEN THE MODELS APPEARS TO TAKE PLACE AT 6Z WEDNESDAY ALONG THE SOUTHERN TENNESSEE BORDER...AS THE 12Z GFS LOOKS TOO DEEP AND WEST WITH THE SURFACE LOW (983 MB)...LIKELY SUFFERING CONVECTIVE FEEDBACK...WHILE THE EURO IS MUCH FARTHER EAST AND WEAKER AT 990 MB. LATEST RAP13 IS IN LINE WITH THE EURO MAGNITUDE BUT IN THE MIDDLE FOR LOCATION. EXPECTATIONS ARE THE COLD DRY EAST-NORTHEAST FEED DOWN LOW SHOULD PROMOTE GOOD WET BULBING WITH LEAD SURGE OF MOISTURE/ACTIVITY TO SUPPORT MOSTLY SNOW DURING WEDNESDAY...WITH THE EXCEPTION BEING TOWARD THE OHIO BORDER (MONROE/WAYNE/LENAWEE COUNTIES)...AS MID LEVEL DRY SLOT WILL ALSO ATTEMPT TO IMPINGE ON THESE AREAS DURING THE AFTERNOON. IF PRECIPITATION DOES TAPER OFF AND SHUT DOWN...SOME MODEST WARMING WILL OCCUR. WITH THAT SAID...EXPECTATIONS ARE FOR 1 TO 5 INCHES IN THOSE LOCATIONS TOWARD THE OHIO BORDER. HIGHER END IF WE STAY MOSTLY SNOW AND DON`T MIX...LOWER END WITH MIXTURE. CONFIDENCE IS HIGHER FOR AREAS ALONG AND NORTHWEST OF THE GLACIAL RIDGE BEING ALL SNOW...WITH LONGER DURATION OF FORCING. ALTHOUGH THE DEFORMATION AXIS LIFTING NORTH TOWARD SAGINAW BAY WEDNESDAY EVENING...AND THE QUESTION MARK IS WILL CONTINUE TO MOVE FARTHER NORTH BEFORE SETTLING BACK SOUTH WEDNESDAY NIGHT INTO THURSDAY...AS THIRD UPPER LEVEL PLAYER CURRENTLY APPROACHING THE SOUTHERN SASKATCHEWAN BORDER THIS AFTERNOON ACTS AS THE KICKER AND ALLOW FOR MID LEVEL RIDGING TO SET IN THURSDAY AFTERNOON...ENDING THE SNOW BY AROUND NOON. WITH MUCH OF THE WEIGHT PLACED ON THE CONSISTENT EURO...TOTAL QPF AMOUNTS IN EXCESS OF 1.25 INCHES ALONG AND NORTH OF I-69 POINT TO STORM TOTALS OF 10 TO 14 INCHES. STRONG NORTHEAST WINDS COMING OFF SAGINAW BAY/LAKE HURON DURING WEDNESDAY WILL PRODUCE GUSTS OF AT LEAST 35 MPH...ESPECIALLY NEAR THE LAKESHORES...BUT WITH THE WET NATURE OF SNOW...LACK OF BLOWING SNOW INITIALLY...VISIBILITIES MAY STRUGGLE TO DROP BELOW 1/4SM FOR ANY EXTENDED TIME...AND HELD OFF ON BLIZZARD WARNING. THIS IS SOMETHING LATER SHIFTS CAN LOOK AT CLOSELY. THE NEXT CHANCE FOR PRECIPITATION WILL DEVELOP SUNDAY FOR SOUTHEAST MICHIGAN. ON SATURDAY AFTERNOON...A CANADIAN LOW DROPS OVER THE DAKOTA`S AND BEGINS ITS EASTWARD TRACK TOWARD MICHIGAN. THIS LOW...WHICH INITIALLY LOOKED FAIRLY WEAK...NOW APPEARS TO BE A LITTLE MORE HEARTY. IT BEARS WATCHING FOR POTENTIAL MEASURABLE SNOWFALL SUNDAY AFTERNOON THROUGH TUESDAY. MARINE... DEVELOPING WINTER STORM OVER EASTERN TEXAS WILL MOVE TO NORTHERN OHIO BY WEDNESDAY EVENING AND CONTINUE ON INTO CANADA WEDNESDAY NIGHT. SURFACE GRADIENT WILL TIGHTEN WITH THIS SYSTEM BRINGING AN INCREASING NORTHEAST FLOW TONIGHT AND WEDNESDAY THAT WILL BACK TO THE NORTHWEST DURING THE DAY THURSDAY. EXPECTING GALES ON LAKE HURON WITH THIS SYSTEM WEDNESDAY AFTERNOON THROUGH THURSDAY NIGHT. HYDROLOGY... A STRONG LOW PRESSURE SYSTEM WILL TRACK THROUGH THE EASTERN OHIO VALLEY ON WEDNESDAY. A DEEP PLUME OF MOISTURE ACCOMPANYING THIS SYSTEM WILL RESULT IN A LONGER DURATION OF WIDESPREAD PRECIPITATION IMPACTING SOUTHEAST MICHIGAN WEDNESDAY THROUGH THURSDAY.THE EXACT TRACK OF THE SURFACE LOW AND RAIN SNOW LINE STILL IS UNCERTAIN. CURRENTLY IT LOOKS TO RUN THROUGH THE FAR EASTERN PORTIONS OF THE FORECAST AREA...MAINLY FROM ABOUT PORT HURON SOUTH THROUGH DETROIT. TOTAL QPF AMOUNTS OF 1.0-1.5 INCHES ARE LIKELY. EVEN IF IT FELL ALL AS RAIN...WOULD ONLY EXPECT THE ROUGE RIVER TO COME NEAR FLOOD STAGE. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY FROM 7 AM WEDNESDAY TO 11 AM EST THURSDAY FOR MIZ076-082. WINTER STORM WARNING FROM 9 AM WEDNESDAY TO 11 AM EST THURSDAY FOR MIZ060>063-068>070-075. WINTER STORM WARNING FROM 11 AM WEDNESDAY TO 11 AM EST THURSDAY FOR MIZ047>049-053>055. LAKE HURON...GALE WARNING FROM 10 AM WEDNESDAY TO 4 AM EST FRIDAY FOR LHZ362-363- 421-422-441-462. GALE WARNING FROM 4 PM WEDNESDAY TO 4 AM EST FRIDAY FOR LHZ361-442- 443-463-464. LAKE ST CLAIR...NONE. MICHIGAN WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....SC UPDATE.......SC DISCUSSION...SF/DE MARINE.......DRC HYDROLOGY....DRC YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1155 PM CST TUE FEB 23 2016 .UPDATE: Issued at 839 PM CST Tue Feb 23 2016 Upper level low was now over southwest AR with a deep surface low ahead of it over northwest MS. Rain was spreading northward into parts of southeast MO and southwest IL with a narow band of rain extending from Linn to Elsberry MO, just west of the St Louis metro area. Latest HRRR model runs spread precipitation through southeast MO and southwest IL late tonight, including most of the St Louis metro area with St Charles county being the western edge of the persistent precipitation shield. The rain should change over to snow over most of the area late tonight leading to potentially hazardous driving conditions Wednesday morning. Snowfall rates may be quite high across parts of southeast MO and southwest IL Wednesday morning and may have to increase snow amounts a little mainly south and east of STL. Will continue Winter Weather Advisory and Wind Advisory for late tonight and Wednesday for southeast MO and southwest IL, including the St Louis metro area. GKS && .SHORT TERM: (Through Wednesday) Issued at 245 PM CST Tue Feb 23 2016 Have made some significant adjustments to the forecast that include metro St. Louis. A winter weather advisory and a wind advisory has already been issued for late tonight and tomorrow. Water vapor shows that the upper low is bottoming out over the Southern Plains that will move northeast tonight and tomorrow morning through the Mid South into the Ohio Valley. The 12Z run of the GFS showed a slight shift to the northwest with the axis of the precipitation whereas the 12Z ECMWF is slightly farther to southeast. GFS is showing intense frontogenesis that will move along the northwestern edge of precipitation band from the eastern Ozarks into central Illinois including the St. Louis metro area from 09-15Z that will likely be producing heavy precipitation rates. Forecast soundings indicate that this will be snow. The latest runs from the HRRR, WRF, and RAP all are supporting this, showing mesoscale banding moving up into eastern Missouri and southwestern Illinois late tonight and early Wednesday. So expect precipitation to move into the area this evening and overnight through the morning hours, with more snow now given the amount of forcing and slightly colder soundings. This now justifies issuing an advisory for the southeastern half of the CWA of snowfall amounts. There will be a time in the morning where the snow could be heavy at times with big wet heavy flakes. It will also be windy as the pressure gradient will be tightening as the surface low deepens. Have also issued a wind advisory for the same location as the winter weather advisory. Have lowered temperatures below guidance. Temperatures will be hampered from rising tomorrow by the clouds and the precipitation. Precipitation will end from west to east during the afternoon as the system begins to lift out of the area. Britt .LONG TERM: (Wednesday Night through Next Tuesday) Issued at 245 PM CST Tue Feb 23 2016 Still looks like we will stay dry from Thursday into Saturday as there will not be much moisture to work with under northwesterly flow aloft. Temperatures will go from below normal to back above normal for the weekend. Still looks like a system will bring us a chance of precipitation on Sunday night. Britt && .AVIATION: (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CST Tue Feb 23 2016 Based on a variety of guidance the previous forecast looks to be in pretty good shape. The low pressure system was located in western TN at 06z and lifting northeastward. It will continue to move northeastward and deepen through the forecast period. Rain had already spread into southern IL and southern MO and will continue to move north and fill in across the St. Louis metro area between 06-08z. Present indications are that the rain will change to snow across far eastern MO into southwest IL in the 09-10z period and then continue through the morning, tapering off by early afternoon. Flight conditions will deteriorate lowering to IFR once the change to snow occurs. The snow should remain east of KCOU and south of KUIN. Northerly winds have been increasing this evening and will continue to ramp up overnight with strong and gusty north-northwest winds lasting through the day on Wednesday. Specifics for KSTL: Rain was encroaching on KSTL from the northwest and southeast and should move into the terminal between 06-08z. Present indications are that the rain will change to snow in the 09-10z period and then continue through the morning, tapering off by early afternoon. Flight conditions will deteriorate, lowering to IFR once the change to snow occurs. Northerly winds have been increasing this evening and will continue to ramp up overnight with strong and gusty north-northwest winds lasting through the day on Wednesday. Glass && .LSX WATCHES/WARNINGS/ADVISORIES: MO...Winter Weather Advisory until 6 PM CST Wednesday FOR Crawford MO- Franklin MO-Iron MO-Jefferson MO-Madison MO-Reynolds MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO- Ste. Genevieve MO-Washington MO. Wind Advisory until 6 PM CST Wednesday FOR Crawford MO-Franklin MO-Iron MO-Jefferson MO-Madison MO-Reynolds MO-St. Charles MO-St. Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve MO-Washington MO. IL...Winter Weather Advisory until 6 PM CST Wednesday FOR Madison IL- Monroe IL-Randolph IL-St. Clair IL. Wind Advisory until 6 PM CST Wednesday FOR Bond IL-Clinton IL- Fayette IL-Jersey IL-Macoupin IL-Madison IL-Marion IL- Monroe IL-Montgomery IL-Randolph IL-St. Clair IL-Washington IL. Winter Weather Advisory from 6 AM to 6 PM CST Wednesday FOR Bond IL-Clinton IL-Fayette IL-Jersey IL-Macoupin IL-Marion IL- Montgomery IL-Washington IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
305 PM CST WED FEB 24 2016 .SHORT TERM...(TONIGHT THROUGH SATURDAY) ISSUED AT 305 PM CST WED FEB 24 2016 PRIMARY FORECAST CONCERNS ARE PCPN AMOUNTS AND PCPN TYPE FROM TONIGHT INTO THURSDAY MORNING. CLOSED LOW AT 500 MB OVER THE NRN PLAINS WILL CONTINUE TO DROP SEWD TONIGHT...BUT WILL BE WEAKENING/SHEARING OUT. IT DID HAVE 12 HOUR HEIGHT FALLS OF OVER 100 METERS IN WRN ND AT 12Z...AND 300 MB WINDS WERE AROUND 115 KNOTS FROM SASK DOWN INTO WRN SD. REGIONAL RADAR LOOP EARLY THIS AFTN SHOWED ECHOES DROPPING SEWD ACROSS SD AND PARTS OF NRN NE. FORECAST SOUNDINGS SUGGEST THAT WE SHOULD HAVE SOME DECENT MID LEVEL LAPSE RATES...AND EVEN A BIT OF ELEVATED CAPE AT SOME SPOTS FOR A FEW HOURS. RECENT EXPERIMENTAL HRRR COMPOSITE REFLECTIVITIES FORECAST FOR THIS EVENING ARE INTERESTING...WITH SOME 40-50 DBZ ECHOES SHOWN. WILL MENTION A MIX OF RAIN AND SNOW SHOWERS (TRENDING TOWARD MOSTLY SNOW BY MID EVENING) THEN A CHANCE OR SLIGHT CHANCE OF SNOW (DEPENDING ON LOCATION AND TIME) AFTER MIDNIGHT. IT APPEARS MOST SNOW AMOUNTS WOULD BE HALF AN INCH OR LESS...WITH POSSIBLY SOME ISOLATED AREAS GETTING AROUND AN INCH. EXPECT LOWS 25 TO 30 AND WINDS WILL BE GRADUALLY INCREASING. FLURRIES COULD LINGER THURSDAY MORNING...THEN CLOUDS SHOULD BE ON THE DECREASE DURING THE DAY WITH BRISK NORTHWEST WINDS. GUSTS MAY BE AROUND 30 MPH OR HIGHER. HIGHS SHOULD BE 35 TO 40 NORTH AND 38 TO 42 SOUTH. THE PERIOD FROM THURSDAY NIGHT THROUGH SATURDAY LOOKS DRY. MID TROPOSPHERIC RIDGE WILL STILL BE BACK OVER WRN NORTH AMERICA EARLY FRIDAY...BUT BUILD EASTWARD TOWARD OUR AREA AND WEAKEN THROUGH SATURDAY. TEMPERATURES SHOULD MODERATE A BIT FRIDAY. STRONGER WARMING SETS IN FOR SATURDAY. SOUTHWEST LOW LEVEL WINDS WILL INCREASE AND MIX DOWN...WITH A MILD DAY ON TAP. 1000-500 MB THICKNESS AND 850 MB TEMPERATURE FORECASTS SUGGEST HIGHS MAINLY IN THE 60S...FAIRLY CLOSE TO OR ABOVE GFS MOS. DEWPOINTS AT THIS TIME LOOK HIGH ENOUGH TO KEEP FIRE DANGER LEVELS DOWN...BUT WILL NEED TO MONITOR AS WE GET CLOSER TO SATURDAY. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 305 PM CST WED FEB 24 2016 A COLD FRONT IS EXPECTED TO PUSH ACROSS THE AREA SATURDAY NIGHT... WITH SOME PCPN POSSIBLY LAGGING BACK BEHIND THE FRONT. KEPT OUR AREA DRY SATURDAY NIGHT...BUT KEPT A SMALL CHANCE OF RAIN GOING FOR ABOUT THE NRN HALF OF THE FCST AREA ON SUNDAY AS A MID LEVEL SHORTWAVE TROUGH AND MODEST 850-500 MB MEAN RH MOVE THROUGH THE REGION. WINDY CONDITIONS ARE LIKELY SUNDAY...POSSIBLY NEAR WIND ADVISORY NUMBERS. WILL HAVE TO KEEP AN EYE ON THAT TOO. OTHERWISE...FLOW ALOFT WILL TURN BACK TO THE NORTHWEST SUNDAY NIGHT AS THE RIDGE REESTABLISHES ITSELF OVER THE ROCKIES. THAT WILL BE SHORT LIVED THOUGH AS SHORTWAVE ENERGY CRASHING INTO THE RIDGE SPREADS PCPN INTO THE ROCKIES AND HIGH PLAINS MONDAY. THE CHANCE OF PCPN IN OUR AREA SHOULD INCREASE MONDAY NIGHT. THE PCPN TYPE ACROSS ERN NE AND SWRN IA WILL BE A MIX OF RAIN AND SNOW...WITH SNOW MORE LIKELY IN OUR NRN ZONES AND RAIN MORE LIKELY SRN ZONES. AT THIS POINT...BELIEVE THE 12Z GFS QPF VALUES ARE TOO HIGH...ESPECIALLY ON TUESDAY. THE 12Z ECMWF HOWEVER MAY BE TOO DRY. AT LEAST SOME SNOW ACCUMULATION DOES APPEAR POSSIBLE TUESDAY. IT DOES LOOK LIKE THIS SYSTEM SHOULD BE MOSTLY OUT OF OUR AREA BY WEDNESDAY...BUT HELD ONTO A SLIGHT CHANCE OF RAIN OR SNOW IN SERN NE AND SWRN IA IN CASE THE SYSTEM SLOWS DOWN A BIT. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1131 AM CST WED FEB 24 2016 WESTERN EDGE OF STRATUS AFFECTING KOMA/KLNK HAS BECOME MORE BROKEN TO SCATTERED...WITH VFR CONDITIONS NOW IN PLACE IN BOTH SITES AND LIKELY TO CONTINUE THROUGH THE AFTERNOON. HAVE INCLUDED TEMPO FOR RAIN/SNOW AT KOFK AND SNOW AT KOMA (DUE TO LATER ARRIVAL)...BUT TOOK MENTION OUT OF KLNK...WHERE POTENTIAL FOR PRECIP IS LOWER. BEHIND PRECIPITATION...MVFR CEILINGS AND GUSTY NORTHWEST WINDS ARE LIKELY TO MOVE IN FOR THE REST OF THE TAF CYCLE. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...MILLER LONG TERM...MILLER AVIATION...MAYES
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1046 PM MST TUE FEB 23 2016 .UPDATE... CANCELLED THE WINTER WX ADVISORY AS REMAINING BAND OF SNOW CONTINUES TO SHRINK. ADDED FREEZING FOG TO SOME NORTHWEST AND NORTH CENTRAL ZONES FOR THE REST OF THE NIGHT AS WELL. LOW TEMPERATURES MAY NOT GET AS COLD ACROSS THE NORTHWEST THIRD OR SO...THANKS TO LINGERING CLOUD COVER BUT DID NOT MAKE ANY CHANGES. && .PREV DISCUSSION...1042 PM MST TUE FEB 23 2016... .AVIATION... 06Z TAF CYCLE LAST SMALL BAND OF SNOW CONTINUES TO DISSIPATE WEST OF KAEG LATE THIS EVENING. HOWEVER...AREAS OF BR AND FZFG HAVE DEVELOPED WHERE EARLIER BANDS EXISTED...INCLUDING AROUND KFMN AND KSAF. THESE TWO SITES WILL LIKELY WAFFLE FOR THE NEXT SEVERAL HOURS BETWEEN LIFR AND VFR CIGS/VSBYS. ATTEMPTED TO INDICATE AS SUCH IN GOING TAFS. EVENTUALLY...INCOMING DRIER AIR SHOULD CLEAR THEM OUT BUT CONFIDENCE IS LOW WHEN THAT WILL BE. LESS ACTIVE ON WEDNESDAY...THOUGH SHOULD SEE SOME CIRRUS MOVE IN OVERHEAD. LIGHTER WINDS OVERALL...BUT COULD SEE SOME WESTERLY BREEZES ACROSS THE PLAINS. A WEAK BACK DOOR FRONT SHOULD MOVE INTO NE NM WED EVENING BRINGING THE WINDS AROUND TO THE N AND NE. 34 && .PREV DISCUSSION...546 PM MST TUE FEB 23 2016... .UPDATE... BAND OF SNOW WHICH HAS SET UP OVER SANTA FE AREA SHOWS LITTLE SIGN OF RELENTING SOON...AND REPORTS RECEIVED SO FAR INDICATE AN ADVISORY PROBABLY NECESSARY...SO WENT AHEAD AND ADDED THEM AS WELL AS THE WEST SLOPES OF THE SANGRES TO THE EXISTING ADVISORY. HRRR AND RAP SHOW THE BAND PERSISTING THRU AROUND 04Z BEFORE TAPERING OFF. UPDATED WSW AND ZFP ALREADY OUT. && .PREV DISCUSSION...318 PM MST TUE FEB 23 2016... .SYNOPSIS... AN UPPER LEVEL TROUGH WILL GRADUALLY EXIT THE AREA TO THE SOUTHEAST TONIGHT...BUT NOT BEFORE DROPPING A FEW INCHES OF ADDITIONAL SNOW IN THE NORTHWEST MOUNTAINS. A RIDGE OF HIGH PRESSURE WILL SLOWLY CROSS THE WESTERN UNITED STATES DURING THE LATTER HALF OF THE WEEK BRINGING WARMING TEMPERATURES AND DRY WEATHER TO NEW MEXICO. AN EXCEPTION WILL BE THE EASTERN PLAINS WHERE A BACK DOOR COLD FRONT WILL STALL THE WARMING TREND ON THURSDAY. HIGH TEMPERATURES SHOULD PEAK AROUND 5 TO 15 DEGREES ABOVE NORMAL ON SATURDAY. && .DISCUSSION... A TRAILING BATCH OF SHORTWAVE ENERGY WILL LINGER OVER NORTHWEST AREAS THIS EVENING BEFORE WHISKING SOUTHEASTWARD. AROUND 1 INCH OF ADDITIONAL SNOW ACCUMULATION WILL BE POSSIBLE IN THE SOUTHERN SAN JUAN MOUNTAINS...AND AROUND 2 INCHES IN THE JEMEZ. THUS...WE PLAN TO CONTINUE THE WINTER WEATHER ADVISORY FOR THE JEMEZ MOUNTAINS THROUGH THIS EVENING. THERE COULD BE SOME PATCHY FOG LATE TONIGHT AND EARLY THIS MORNING IN THE UPPER RIO GRANDE AND LOWER CHAMA RIVER VALLEYS...ESPECIALLY WHERE SNOW RECENTLY ACCUMULATED...AS SKIES CLEAR LATER TONIGHT. THIS MAY BE THE CASE IN ALBUQUERQUES NE HEIGHTS AND THE WESTERN FOOTHILLS OF THE SANDIA MOUNTAINS...TOO. MODELS NOW SHOW SUNDAYS UPPER LEVEL TROUGH PASSING TOO FAR NORTH OF NM FOR ANY PRECIPITATION. THE WEATHER SYSTEM WILL STILL SEND A COLD FRONT SOUTHWARD THROUGH THE STATE...AND WINDS WILL PROBABLY BECOME GUSTY. ANOTHER STORM SYSTEM WITH A SIMILAR LOOK TO TODAYS ONGOING SYSTEM IS PROGGED TO CLIP NE NM MONDAY AND MONDAY NIGHT. 44 && .FIRE WEATHER... LIGHT RAIN AND SNOW OVER THE AREA WILL TAPER OFF WHILE LINGERING INTO THE NORTHERN HIGH TERRAIN THIS EVENING. ACCUMULATING SNOWFALL HAS IMPACTED MUCH OF THE AREA FROM THE NORTHERN MTS EAST ACROSS THE NORTHEAST PLAINS...WHERE ROUGHLY 3 TO 8 INCHES HAS BEEN REPORTED... WITH LOCALLY HIGHER AMOUNTS NEAR 1 FT. THE COLDER TEMPERATURES AND STRONG WINDS HAVE BEEN THE OTHER STORY TODAY...AND THIS WILL SLOWLY TREND LIGHTER AND WARMER INTO WEDNESDAY AND THURSDAY. OVERNIGHT LOWS WILL BE THE COLDEST IN NEARLY TWO WEEKS AREAWIDE TONIGHT AND WEDNESDAY NIGHT...WITH LOTS OF SINGLE DIGITS TO TEENS AND 20S. THIS ALONG WITH SNOWMELT WILL HELP WITH IMPROVING RH RECOVERIES FOR THE NEXT COUPLE DAYS. VERY DRY AIR WORKING INTO THE STATE THURSDAY INTO FRIDAY WILL STILL ALLOW FOR SOME MIN RH VALUES IN THE TEENS. VENT RATES WILL DETERIORATE AS WELL INTO FRIDAY BEFORE TRENDING BETTER OVER THE WEEKEND. THE NEXT STORM SYSTEM WILL ATTEMPT TO MOVE ACROSS THE NORTHERN HALF OF THE STATE LATE SUNDAY HOWEVER MODELS ARE AT ODDS WITH WHETHER OR NOT THIS WILL OCCUR. GUYER && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1042 PM MST TUE FEB 23 2016 .AVIATION... 06Z TAF CYCLE LAST SMALL BAND OF SNOW CONTINUES TO DISSIPATE WEST OF KAEG LATE THIS EVENING. HOWEVER...AREAS OF BR AND FZFG HAVE DEVELOPED WHERE EARLIER BANDS EXISTED...INCLUDING AROUND KFMN AND KSAF. THESE TWO SITES WILL LIKELY WAFFLE FOR THE NEXT SEVERAL HOURS BETWEEN LIFR AND VFR CIGS/VSBYS. ATTEMPTED TO INDICATE AS SUCH IN GOING TAFS. EVENTUALLY...INCOMING DRIER AIR SHOULD CLEAR THEM OUT BUT CONFIDENCE IS LOW WHEN THAT WILL BE. LESS ACTIVE ON WEDNESDAY...THOUGH SHOULD SEE SOME CIRRUS MOVE IN OVERHEAD. LIGHTER WINDS OVERALL...BUT COULD SEE SOME WESTERLY BREEZES ACROSS THE PLAINS. A WEAK BACK DOOR FRONT SHOULD MOVE INTO NE NM WED EVENING BRINGING THE WINDS AROUND TO THE N AND NE. 34 && .PREV DISCUSSION...546 PM MST TUE FEB 23 2016... .UPDATE... BAND OF SNOW WHICH HAS SET UP OVER SANTA FE AREA SHOWS LITTLE SIGN OF RELENTING SOON...AND REPORTS RECEIVED SO FAR INDICATE AN ADVISORY PROBABLY NECESSARY...SO WENT AHEAD AND ADDED THEM AS WELL AS THE WEST SLOPES OF THE SANGRES TO THE EXISTING ADVISORY. HRRR AND RAP SHOW THE BAND PERSISTING THRU AROUND 04Z BEFORE TAPERING OFF. UPDATED WSW AND ZFP ALREADY OUT. && .PREV DISCUSSION...318 PM MST TUE FEB 23 2016... .SYNOPSIS... AN UPPER LEVEL TROUGH WILL GRADUALLY EXIT THE AREA TO THE SOUTHEAST TONIGHT...BUT NOT BEFORE DROPPING A FEW INCHES OF ADDITIONAL SNOW IN THE NORTHWEST MOUNTAINS. A RIDGE OF HIGH PRESSURE WILL SLOWLY CROSS THE WESTERN UNITED STATES DURING THE LATTER HALF OF THE WEEK BRINGING WARMING TEMPERATURES AND DRY WEATHER TO NEW MEXICO. AN EXCEPTION WILL BE THE EASTERN PLAINS WHERE A BACK DOOR COLD FRONT WILL STALL THE WARMING TREND ON THURSDAY. HIGH TEMPERATURES SHOULD PEAK AROUND 5 TO 15 DEGREES ABOVE NORMAL ON SATURDAY. && .DISCUSSION... A TRAILING BATCH OF SHORTWAVE ENERGY WILL LINGER OVER NORTHWEST AREAS THIS EVENING BEFORE WHISKING SOUTHEASTWARD. AROUND 1 INCH OF ADDITIONAL SNOW ACCUMULATION WILL BE POSSIBLE IN THE SOUTHERN SAN JUAN MOUNTAINS...AND AROUND 2 INCHES IN THE JEMEZ. THUS...WE PLAN TO CONTINUE THE WINTER WEATHER ADVISORY FOR THE JEMEZ MOUNTAINS THROUGH THIS EVENING. THERE COULD BE SOME PATCHY FOG LATE TONIGHT AND EARLY THIS MORNING IN THE UPPER RIO GRANDE AND LOWER CHAMA RIVER VALLEYS...ESPECIALLY WHERE SNOW RECENTLY ACCUMULATED...AS SKIES CLEAR LATER TONIGHT. THIS MAY BE THE CASE IN ALBUQUERQUES NE HEIGHTS AND THE WESTERN FOOTHILLS OF THE SANDIA MOUNTAINS...TOO. MODELS NOW SHOW SUNDAYS UPPER LEVEL TROUGH PASSING TOO FAR NORTH OF NM FOR ANY PRECIPITATION. THE WEATHER SYSTEM WILL STILL SEND A COLD FRONT SOUTHWARD THROUGH THE STATE...AND WINDS WILL PROBABLY BECOME GUSTY. ANOTHER STORM SYSTEM WITH A SIMILAR LOOK TO TODAYS ONGOING SYSTEM IS PROGGED TO CLIP NE NM MONDAY AND MONDAY NIGHT. 44 && .FIRE WEATHER... LIGHT RAIN AND SNOW OVER THE AREA WILL TAPER OFF WHILE LINGERING INTO THE NORTHERN HIGH TERRAIN THIS EVENING. ACCUMULATING SNOWFALL HAS IMPACTED MUCH OF THE AREA FROM THE NORTHERN MTS EAST ACROSS THE NORTHEAST PLAINS...WHERE ROUGHLY 3 TO 8 INCHES HAS BEEN REPORTED... WITH LOCALLY HIGHER AMOUNTS NEAR 1 FT. THE COLDER TEMPERATURES AND STRONG WINDS HAVE BEEN THE OTHER STORY TODAY...AND THIS WILL SLOWLY TREND LIGHTER AND WARMER INTO WEDNESDAY AND THURSDAY. OVERNIGHT LOWS WILL BE THE COLDEST IN NEARLY TWO WEEKS AREAWIDE TONIGHT AND WEDNESDAY NIGHT...WITH LOTS OF SINGLE DIGITS TO TEENS AND 20S. THIS ALONG WITH SNOWMELT WILL HELP WITH IMPROVING RH RECOVERIES FOR THE NEXT COUPLE DAYS. VERY DRY AIR WORKING INTO THE STATE THURSDAY INTO FRIDAY WILL STILL ALLOW FOR SOME MIN RH VALUES IN THE TEENS. VENT RATES WILL DETERIORATE AS WELL INTO FRIDAY BEFORE TRENDING BETTER OVER THE WEEKEND. THE NEXT STORM SYSTEM WILL ATTEMPT TO MOVE ACROSS THE NORTHERN HALF OF THE STATE LATE SUNDAY HOWEVER MODELS ARE AT ODDS WITH WHETHER OR NOT THIS WILL OCCUR. GUYER && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1230 PM EST WED FEB 24 2016 .SYNOPSIS...A POWERFUL UPPER LEVEL LOW AND ACCOMPANYING SURFACE CYCLONE THAT WILL TRACK THROUGH THE TN AND OH VALLEYS. A TRAILING COLD FRONT WILL SWEEP EAST ACROSS OUR REGION LATE THIS AFTERNOON AND EVENING. BLUSTERY CONDITIONS WILL FOLLOW AS HIGH PRESSURE BUILDS EAST TONIGHT AND THU. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1245 PM WEDNESDAY... ...STRONG WINDS AND SEVERE THUNDERSTORMS LIKELY THIS AFTERNOON... TORNADO WATCH REMAINS IN EFFECT THROUGH 7 PM...WITH WIDESPREAD SHOWERS AND A FEW SEVERE THUNDERSTORMS ONGOING EARLY THIS AFTERNOON. THE POTENTIALLY STRONGEST LINE IS MOVING ACROSS THE YADKIN RIVER INTO THE WESTERN PIEDMONT...WILL REACH THE TRIAD BETWEEN 1 AND 2 PM...AND INTO THE TRIANGLE AREA 3-4 PM. OVERALL FORECAST TRENDS ARE ON TRACK. PREVIOUS DISCUSSIONS...WEDGE HAS ERODED OUT OF ALL BUT THE FAR NORTHWEST PIEDMONT COUNTIES THIS MORNING...SETTING TABLE FOR SOME MODEST DESTABILIZATION HEADING INTO THE AFTERNOON. WINDS HAVE BEEN ON THE UPTICK DUE TO THE MIXING...WITH GUSTS EXCEEDING 30 MPH BECOMING MORE NUMEROUS. SOME MINOR UPDATES TO REFLECT TIMING OF THESE TRENDS ARE IN ORDER...OTHERWISE THE SEVERE THREAT IS ON TRACK PER DISCUSSION BELOW. AN UPPER LEVEL TROUGH WILL SWING ACROSS THE SOUTHEAST STATES TODAY...WHILE THE ASSOCIATED JET STREAK STRENGTHENS FROM THE GULF COAST TOWARD THE CAROLINAS AND AN INTENSE LOW-LEVEL JET (60 KT AT 850MB AT KFFC) TRANSLATES ACROSS CENTRAL NC...ALL CONCURRENT WITH A STABILIZES AIRMASS IN THE WAKE OF AN INLAND RETREATING WEDGE/COASTAL WARM FRONTS. THIS WILL SET THE STAGE FOR A MULTIFACETED AND POTENTIALLY DANGEROUS SEVERE WEATHER SITUATION. GIVEN THE LARGE SCALE FORCING...IT APPEARS THERE WILL BE A COUPLE TIME PERIODS FAVORABLE FOR SEVERE WEATHER. THE FIRST WILL UNFOLD THIS MORNING (AND MAY ALREADY BE GETTING GOING WITH AN ELEVATED SUPERCELL APPROACHING RICHMOND COUNTY AT 3AM) AS WARM ADVECTION AND MUCAPE INCREASE ATOP THE STUBBORN WEDGE AIRMASS WHICH IS STILL NEAR THE COAST. THE WEDGE FRONT AND EVENTUALLY THE TRUE WARM SECTOR ARE PROGGED TO SLOWLY MIX INLAND THIS MORNING AND THEN MORE QUICKLY BY MIDDAY...WITH THE NORTHWEST PIEDMONT LIKELY TO BREAK OUT BY 2PM. MANY OF THE CAMS SHOW CONTINUED DEVELOPMENT OF CONVECTION TO OUR SOUTH THAT MOVES NORTH...AND WITH TIME SURFACE BASED CONVECTION WILL BE MORE LIKELY...WITH A GROWING CONCERN FOR THOSE STORMS INTERSECTING THE HELICITY LADEN WARM FRONT (0-3KM SRH OF 300-400 M2/S2). THE BEST TIME FRAME FOR THIS APPEARS TO BE FROM 5 AM THROUGH 11AM...MAINLY IN THE COASTAL PLAIN. AND THEN THIS AFTERNOON MODELS SEEM TO BE KEYING IN ON DEVELOPMENT FORCED BY THE MAIN UPPER TROUGH AND ALONG A CONFLUENCE ZONE (AHEAD OF THE MAIN COLD FRONT) THAT IS CURRENTLY OVER CENTRAL AL. THIS LINE WILL HAVE THE POTENTIAL TO STRENGTHEN RAPIDLY AS IT ENCOUNTERS THE WARM SECTOR...CHARACTERIZED BY TEMPS IN THE UPPER 60S/LOWER 70S AND DEWPOINTS IN THE MID 60S...AND 500-1000 J/KG MLCAPE. THE WELL-TIMED ARRIVAL OF A DRY SLOT MAY ALSO HELP TO ENHANCE INSTABILITY...AS WELL AS DCAPE. LOW-LEVEL WINDS WILL HAVE VEERED TO MORE SOUTHERN BY THEN...BUT 0-3KM SRH WILL STILL BE 200-300 M2/S2 AND LONG HODOGRAPHS WILL SUPPORT BOWING LINE SEGMENTS AND SUPERCELLS. THE TIME FRAME FOR THIS APPEARS TO BETWEEN NOON AND 6PM. THE HRRR HAS REALLY LATCHED ONTO THIS IN THE PAST 3 OR 4 RUNS. SPC HAS UPGRADED A PORTION OF THE AREA TO A MODERATE RISK (FROM THE TRIANGLE NORTH AND EAST)...OWING TO THE BEST OVERLAP OF KINEMATICS AND EVENTUALLY DESTABILIZATION. DAMAGING WINDS WILL BE POSSIBLE FOR NEARLY ALL OF CENTRAL NC (POSSIBLY MISSING THE NORTHWEST PIEDMONT IF THEY DO NOT BREAK OUT PRIOR TO THE SECOND LINE OF CONVECTION) ...IF NOT FROM CONVECTION THEN FROM 20-25MPH WINDS AND GUSTS TO 40- 45MPH (ENHANCED EVEN BY SUB-SEVERE SHOWERS AND STORMS). A FEW TORNADOES ARE ALSO POSSIBLE AND A STRONG...LONG TRACK TORNADO CANNOT BE RULED OUT. THE CURRENT WIND ADVISORY WILL CONTINUE FROM 9AM THROUGH MIDNIGHT. THE CONVECTIVE LINE SHOULD RACE EAST OF THE AREA BY 7PM OR SO...WITH A FEW ADDITIONAL SHOWERS POSSIBLE ALONG THE MAIN COLD FRONT. LOWS WILL BOTTOM OUT IN THE 41-48 RANGE. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 355 AM WEDNESDAY... SHORT WAVE ENERGY WILL CONTINUE TO ROTATE ACROSS THE OHIO VALLEY AROUND THE MAIN UPPER TROF THURSDAY AND THURSDAY NIGHT...WITH THE FINAL AND STRONGEST SHORT WAVE SHIFTING THE TROF AXIS OFFSHORE BY FRIDAY MORNING. MOISTURE WILL BE SQUEEZED OUT OVER THE WESTERN SLOPES...WITH SCATTERED TO BROKEN STRATOCUMULUS (PERHAPS A STRAY SPRINKLE OR TWO IN THE TRIAD) SPILLING ACROSS THE NORTHERN TIER. COLD AIR WILL BE REINFORCED...WITH A STRONG PRESSURE GRADIENT LINGERING THURSDAY FEATURING SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO AROUND 35 MPH...AND WITH A FEW INFREQUENT GUSTS INTO THE UPPER 30S TO NEAR 40S KTS POSSIBLE. HIGHS WILL BE A CATEGORY OR SO BELOW NORMAL...WITH THE AFOREMENTIONED BLUSTERY CONDITIONS AND AN ASSOCIATED CHILLIER FEEL THAN TEMPERATURES IN THE LOW TO MID 50S WOULD OTHERWISE SUGGEST. SKIES WILL BECOME CLEAR OVERNIGHT...WITH THE DIURNAL TEMPERATURE FALL TEMPERED BY GOOD MIXING TO KEEP FRIDAY MORNING MINS MOSTLY IN THE LOWER 30S. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... AS OF 1000 AM WEDNESDAY... COOL AIR ADVECTION DUE TO BROAD TROFFING ACROSS THE EASTERN CONUS WILL RESULT IN DRY WEATHER THROUGH THE WEEKEND...WITH HIGHS STRUGGLING TO REACH 50 ON BOTH FRIDAY AND SATURDAY. MORNING MINS WILL BE IN THE 30S SATURDAY AND SUNDAY MORNINGS. A FINAL MOISTURE STARVED SHORT WAVE WILL MOVE EAST ACROSS THE AREA LATER SATURDAY...INITIATING A SHORT-LIVED WARMING TREND THAT WILL BEGIN SUNDAY AS PROGRESSIVE SHORT WAVE RIDGING MOVES ACROSS CONCURRENT WITH MILD HIGH PRESSURE BUILDING IN FROM THE SOUTH. HIGHS SUNDAY WILL REACH NEAR NORMAL...MID TO UPPER 50S...AND REACH 60 TO 65 ON MONDAY AHEAD OF OUR NEXT WEAK AND DRY COLD FRONT WHICH WILL MOVE THROUGH LATER MONDAY TO COOL US BACK INTO THE MID AND UPPER 50S ON TUESDAY. THE FRONT WILL DISSIPATE AND LIFT NORTH WITH MILD RETURN FLOW DEVELOPING MID WEEK AS A STRONGER FRONTAL SYSTEM TAKES SHAPE OVER THE LOWER PLAINS...WITH EXPECTED IMPACTS NOT EXPECTED TO REACH THE EAST COAST UNTIL THURSDAY. HIGHS WEDNESAY SHOULD REACH THE LOW TO MID 60S. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 1230 PM WEDNESDAY... MAIN HAZARD WILL BE SEVERE STORMS THIS AFTERNOON...INITIAL COLD AIR WEDGE HAS ERODED AND AN INTITIAL LINE OF POTENTIALLY SEVERE THUNDERSTORMS WILL BE MOVING EAST...INTO THE TRIAD TAF SITES (GSO/INT) BETWEEN 18 AND 20Z. EASTERN SITES MAY EXPECT SCATTERED ACTIVITY THROUGH THE AFTERNOON...WITH THE MAIN LINE REACHING THE SITES 19-22Z. GUSTS ACCOMPANYING THE STORMS COULD REACH 50 KNOTS AND POSSIBLY PRODUCE A TORNADO OR TWO. MEANWHILE...THE PREVAILING CONDITIONS THROUGH 00Z WILL FEATURE ROUNDS OF SHOWERS WITH MVFR CEILINGS AND SUSTAINED SOUTHERLY WINDS 15 TO 20 KNOTS WITH GUSTS TO 30 KNOTS. AFTER THE CONVECTION WANES...VFR CONDITIONS ARE EXPECTED OVERNIGHT...WITH SOUTH TO SOUTHWEST WINDS SUBSIDING TO 10 TO 15 KNOTS GUSTING 20 TO 25 OVERNIGHT. CONDITIONS THURSDAY REMAIN VFR...BUT WINDS WILL PICK UP AGAIN BY MIDMORNING...WITH SOUTHWEST TO WEST WINDS 15 TO 20 GUSTING TO 30 KNOTS AFTER 15Z...SUBSIDING TO LESS THAN 10 KNOTS AROUND 00Z TOMORROW EVENING (BEYOND THE VALID TAF PERIOD). FRIDAY AND BEYOND...VFR CONDITIONS WITH NO PRECIPITATION ARE EXPECTED THROUGH THE WEEKEND...LIKELY LINGERING INTO MIDWEEK. && .RAH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY THROUGH MIDNIGHT EST TONIGHT FOR NCZ008>011-024>028-040>043-073>078-083>086-088-089. && $$ SYNOPSIS...26/MLM NEAR TERM...22/MLM SHORT TERM...26/MLM LONG TERM...MLM AVIATION...MLM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
956 AM EST WED FEB 24 2016 .SYNOPSIS...A WARM FRONT MOVED NORTH OF THE AREA THIS MORNING...IN ADVANCE OF A POWERFUL UPPER LEVEL LOW AND ACCOMPANYING SURFACE CYCLONE THAT WILL TRACK THROUGH THE TN AND OH VALLEYS. A TRAILING COLD FRONT WILL SWEEP EAST ACROSS OUR REGION LATE THIS AFTERNOON AND EVENING. BLUSTERY CONDITIONS WILL FOLLOW AS HIGH PRESSURE BUILDS EAST TONIGHT AND THU. && .NEAR TERM /THROUGH TONIGHT/... AS OF 956 AM WEDNESDAY... ...STRONG WINDS AND SEVERE THUNDERSTORMS LIKELY TODAY... WEDGE HAS ERODED OUT OF ALL BUT THE FAR NORTHWEST PIEDMONT COUNTIES THIS MORNING...SETTING TABLE FOR SOME MODEST DESTABILIZATION HEADING INTO THE AFTERNOON. WINDS HAVE BEEN ON THE UPTICK DUE TO THE MIXING ...WITH GUSTS EXCEEDING 30 MPH BECOMING MORE NUMEROUS. SOME MINOR UPDATES TO REFLECT TIMING OF THESE TRENDS ARE IN ORDER...OTHERWISE THE SEVERE THREAT IS ON TRACK PER DISCUSSION BELOW. PREVIOUS DISCUSSION...AN UPPER LEVEL TROUGH WILL SWING ACROSS THE SOUTHEAST STATES TODAY...WHILE THE ASSOCIATED JET STREAK STRENGTHENS FROM THE GULF COAST TOWARD THE CAROLINAS AND AN INTENSE LOW-LEVEL JET (60 KT AT 850MB AT KFFC) TRANSLATES ACROSS CENTRAL NC...ALL CONCURRENT WITH A STABILIZES AIRMASS IN THE WAKE OF AN INLAND RETREATING WEDGE/COASTAL WARM FRONTS. THIS WILL SET THE STAGE FOR A MULTIFACETED AND POTENTIALLY DANGEROUS SEVERE WEATHER SITUATION. GIVEN THE LARGE SCALE FORCING...IT APPEARS THERE WILL BE A COUPLE TIME PERIODS FAVORABLE FOR SEVERE WEATHER. THE FIRST WILL UNFOLD THIS MORNING (AND MAY ALREADY BE GETTING GOING WITH AN ELEVATED SUPERCELL APPROACHING RICHMOND COUNTY AT 3AM) AS WARM ADVECTION AND MUCAPE INCREASE ATOP THE STUBBORN WEDGE AIRMASS WHICH IS STILL NEAR THE COAST. THE WEDGE FRONT AND EVENTUALLY THE TRUE WARM SECTOR ARE PROGGED TO SLOWLY MIX INLAND THIS MORNING AND THEN MORE QUICKLY BY MIDDAY...WITH THE NORTHWEST PIEDMONT LIKELY TO BREAK OUT BY 2PM. MANY OF THE CAMS SHOW CONTINUED DEVELOPMENT OF CONVECTION TO OUR SOUTH THAT MOVES NORTH...AND WITH TIME SURFACE BASED CONVECTION WILL BE MORE LIKELY...WITH A GROWING CONCERN FOR THOSE STORMS INTERSECTING THE HELICITY LADEN WARM FRONT (0-3KM SRH OF 300-400 M2/S2). THE BEST TIME FRAME FOR THIS APPEARS TO BE FROM 5 AM THROUGH 11AM...MAINLY IN THE COASTAL PLAIN. AND THEN THIS AFTERNOON MODELS SEEM TO BE KEYING IN ON DEVELOPMENT FORCED BY THE MAIN UPPER TROUGH AND ALONG A CONFLUENCE ZONE (AHEAD OF THE MAIN COLD FRONT) THAT IS CURRENTLY OVER CENTRAL AL. THIS LINE WILL HAVE THE POTENTIAL TO STRENGTHEN RAPIDLY AS IT ENCOUNTERS THE WARM SECTOR...CHARACTERIZED BY TEMPS IN THE UPPER 60S/LOWER 70S AND DEWPOINTS IN THE MID 60S...AND 500-1000 J/KG MLCAPE. THE WELL-TIMED ARRIVAL OF A DRY SLOT MAY ALSO HELP TO ENHANCE INSTABILITY...AS WELL AS DCAPE. LOW-LEVEL WINDS WILL HAVE VEERED TO MORE SOUTHERN BY THEN...BUT 0-3KM SRH WILL STILL BE 200-300 M2/S2 AND LONG HODOGRAPHS WILL SUPPORT BOWING LINE SEGMENTS AND SUPERCELLS. THE TIME FRAME FOR THIS APPEARS TO BETWEEN NOON AND 6PM. THE HRRR HAS REALLY LATCHED ONTO THIS IN THE PAST 3 OR 4 RUNS. SPC HAS UPGRADED A PORTION OF THE AREA TO A MODERATE RISK (FROM THE TRIANGLE NORTH AND EAST)...OWING TO THE BEST OVERLAP OF KINEMATICS AND EVENTUALLY DESTABILIZATION. DAMAGING WINDS WILL BE POSSIBLE FOR NEARLY ALL OF CENTRAL NC (POSSIBLY MISSING THE NORTHWEST PIEDMONT IF THEY DO NOT BREAK OUT PRIOR TO THE SECOND LINE OF CONVECTION) ...IF NOT FROM CONVECTION THEN FROM 20-25MPH WINDS AND GUSTS TO 40- 45MPH (ENHANCED EVEN BY SUB-SEVERE SHOWERS AND STORMS). A FEW TORNADOES ARE ALSO POSSIBLE AND A STRONG...LONG TRACK TORNADO CANNOT BE RULED OUT. THE CURRENT WIND ADVISORY WILL CONTINUE FROM 9AM THROUGH MIDNIGHT. THE CONVECTIVE LINE SHOULD RACE EAST OF THE AREA BY 8PM OR SO...WITH A FEW ADDITIONAL SHOWERS POSSIBLE ALONG THE MAIN COLD FRONT. LOWS WILL BOTTOM OUT IN THE41-48 RANGE. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 355 AM WEDNESDAY... SHORT WAVE ENERGY WILL CONTINUE TO ROTATE ACROSS THE OHIO VALLEY AROUND THE MAIN UPPER TROF THURSDAY AND THURSDAY NIGHT...WITH THE FINAL AND STRONGEST SHORT WAVE SHIFTING THE TROF AXIS OFFSHORE BY FRIDAY MORNING. MOISTURE WILL BE SQUEEZED OUT OVER THE WESTERN SLOPES...WITH SCATTERED TO BROKEN STRATOCUMULUS (PERHAPS A STRAY SPRINKLE OR TWO IN THE TRIAD) SPILLING ACROSS THE NORTHERN TIER. COLD AIR WILL BE REINFORCED...WITH A STRONG PRESSURE GRADIENT LINGERING THURSDAY FEATURING SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO AROUND 35 MPH...AND WITH A FEW INFREQUENT GUSTS INTO THE UPPER 30S TO NEAR 40S KTS POSSIBLE. HIGHS WILL BE A CATEGORY OR SO BELOW NORMAL...WITH THE AFOREMENTIONED BLUSTERY CONDITIONS AND AN ASSOCIATED CHILLIER FEEL THAN TEMPERATURES IN THE LOW TO MID 50S WOULD OTHERWISE SUGGEST. SKIES WILL BECOME CLEAR OVERNIGHT...WITH THE DIURNAL TEMPERATURE FALL TEMPERED BY GOOD MIXING TO KEEP FRIDAY MORNING MINS MOSTLY IN THE LOWER 30S. && .LONG TERM /FRIDAY THROUGH WEDNESDAYDAY/... AS OF 1000 AM WEDNESDAY... COOL AIR ADVECTION DUE TO BROAD TROFFING ACROSS THE EASTERN CONUS WILL RESULT IN DRY WEATHER THROUGH THE WEEKEND...WITH HIGHS STRUGGLING TO REACH 50 ON BOTH FRIDAY AND SATURDAY. MORNING MINS WILL BE IN THE 30S SATURDAY AND SUNDAY MORNINGS. A FINAL MOISTURE STARVED SHORT WAVE WILL MOVE EAST ACROSS THE AREA LATER SATURDAY...INITIATING A SHORT-LIVED WARMING TREND THAT WILL BEGIN SUNDAY AS PROGRESSIVE SHORT WAVE RIDGING MOVES ACROSS CONCURRENT WITH MILD HIGH PRESSURE BUILDING IN FROM THE SOUTH. HIGHS SUNDAY WILL REACH NEAR NORMAL...MID TO UPPER 50S...AND REACH 60 TO 65 ON MONDAY AHEAD OF OUR NEXT WEAK AND DRY COLD FRONT WHICH WILL MOVE THROUGH LATER MONDAY TO COOL US BACK INTO THE MID AND UPPER 50S ON TUESDAY. THE FRONT WILL DISSIPATE AND LIFT NORTH WITH MILD RETURN FLOW DEVELOPING MID WEEK AS A STRONGER FRONTAL SYSTEM TAKES SHAPE OVER THE LOWER PLAINS...WITH EXPECTED IMPACTS NOT EXPECTED TO REACH THE EAST COAST UNTIL THURSDAY. HIGHS WEDNESAY SHOULD REACH THE LOW TO MID 60S. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... AS OF 900 AM WEDNESDAY... COLD AIR DAMMING...AND ASSOCIATED COOL AND SATURATED AIR AND LIFR CONDITIONS TRAPPED BELOW A STRONG TEMPERATURE INVERSION CENTERED AROUND 2000-2500 FT...WILL CONTINUE UNTIL A WARM FRONT RETREATS NORTH THROUGH CENTRAL NC LATE THIS MORNING THROUGH MIDDAY. WINDS IN THE INVERSION LAYER WILL RAPIDLY STRENGTHEN BETWEEN 9-12Z...OWING TO THE APPROACH OF A POWERFUL UPPER LEVEL LOW FROM THE MID-SOUTH; AND THIS WILL RESULT IN THE OCCURRENCE OF LOW LEVEL WIND SHEAR UNTIL THE INVERSION BREAKS WITH THE PASSAGE OF THE WARM FRONT. THE WARM FRONT WILL MARK THE LEADING EDGE OF AN INCREASINGLY WINDY...WARM...AND HUMID REGIME --ONE CHARACTERIZED BY MVFR CEILINGS OR OCCASIONAL SCATTERING TO VFR-- AND STRONG SSE SURFACE WINDS BETWEEN 15-25 KTS WITH GUSTS OF 30-40 KTS. THE TIMING OF THE PASSAGE OF THIS WARM FRONT WILL LIKELY BE BETWEEN 11-14Z AT FAY AND RWI; 12-15Z AT RDU...AND 14-17Z AT GSO/INT. IN ADDITION...MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS WILL OVERSPREAD CENTRAL NC...THE FIRST OF WHICH IS NOW ABOUT TO CROSS THE SC STATE LINE. THESE INITIAL SHOWERS AND STORMS WILL BE BASED WITHIN THE AFOREMENTIONED INVERSION AND CONSEQUENTLY NOT POSE A RISK OF DAMAGING CONVECTIVE WINDS AND/OR TORNADOES. HOWEVER...SUBSEQUENT ROUNDS OF STORMS BETWEEN 15-22Z WILL LIKELY RESULT IN SWATHS OF STRAIGHT LINE WINDS IN EXCESS OF 70 MPH AND A FEW TORNADOES... PARTICULARLY AT RDU/FAY/RWI. A COLD FRONT WILL SWEEP THE STORMS AND SUB-VFR CONDITIONS EAST OF CENTRAL NC LATER THIS AFTERNOON AND EVENING. OUTLOOK: VFR CONDITIONS...BUT WITH BLUSTERY WESTERLY WINDS...WILL FOLLOW FOR TONIGHT AND ESPECIALLY THU. && .RAH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT EST TONIGHT FOR NCZ008>011-024>028-040>043-073>078-083>086-088-089. && $$ SYNOPSIS...26 NEAR TERM...22/MLM SHORT TERM...26/MLM LONG TERM...MLM AVIATION...26
AREA FORECAST DISCUSSION
NWS RALEIGH NC
925 AM EST WED FEB 24 2016 .SYNOPSIS...A WARM FRONT WILL RETREAT NORTH TODAY...IN ADVANCE OF A POWERFUL UPPER LEVEL LOW AND ACCOMPANYING SURFACE CYCLONE THAT WILL TRACK THROUGH THE TN AND OH VALLEYS. A TRAILING COLD FRONT WILL SWEEP EAST ACROSS OUR REGION LATE THIS AFTERNOON AND EVENING. BLUSTERY CONDITIONS WILL FOLLOW AS HIGH PRESSURE BUILDS EAST TONIGHT AND THU. && .NEAR TERM /THROUGH TONIGHT/... AS OF 345 AM WEDNESDAY... ...STRONG WINDS AND SEVERE THUNDERSTORMS LIKELY TODAY... AN UPPER LEVEL TROUGH WILL SWING ACROSS THE SOUTHEAST STATES TODAY...WHILE THE ASSOCIATED JET STREAK STRENGTHENS FROM THE GULF COAST TOWARD THE CAROLINAS AND AN INTENSE LOW-LEVEL JET (60 KT AT 850MB AT KFFC) TRANSLATES ACROSS CENTRAL NC...ALL CONCURRENT WITH A STABILIZES AIRMASS IN THE WAKE OF AN INLAND RETREATING WEDGE/COASTAL WARM FRONTS. THIS WILL SET THE STAGE FOR A MULTIFACETED AND POTENTIALLY DANGEROUS SEVERE WEATHER SITUATION. GIVEN THE LARGE SCALE FORCING...IT APPEARS THERE WILL BE A COUPLE TIME PERIODS FAVORABLE FOR SEVERE WEATHER. THE FIRST WILL UNFOLD THIS MORNING (AND MAY ALREADY BE GETTING GOING WITH AN ELEVATED SUPERCELL APPROACHING RICHMOND COUNTY AT 3AM) AS WARM ADVECTION AND MUCAPE INCREASE ATOP THE STUBBORN WEDGE AIRMASS WHICH IS STILL NEAR THE COAST. THE WEDGE FRONT AND EVENTUALLY THE TRUE WARM SECTOR ARE PROGGED TO SLOWLY MIX INLAND THIS MORNING AND THEN MORE QUICKLY BY MIDDAY...WITH THE NORTHWEST PIEDMONT LIKELY TO BREAK OUT BY 2PM. MANY OF THE CAMS SHOW CONTINUED DEVELOPMENT OF CONVECTION TO OUR SOUTH THAT MOVES NORTH...AND WITH TIME SURFACE BASED CONVECTION WILL BE MORE LIKELY...WITH A GROWING CONCERN FOR THOSE STORMS INTERSECTING THE HELICITY LADEN WARM FRONT (0-3KM SRH OF 300-400 M2/S2). THE BEST TIME FRAME FOR THIS APPEARS TO BE FROM 5 AM THROUGH 11AM...MAINLY IN THE COASTAL PLAIN. AND THEN THIS AFTERNOON MODELS SEEM TO BE KEYING IN ON DEVELOPMENT FORCED BY THE MAIN UPPER TROUGH AND ALONG A CONFLUENCE ZONE (AHEAD OF THE MAIN COLD FRONT) THAT IS CURRENTLY OVER CENTRAL AL. THIS LINE WILL HAVE THE POTENTIAL TO STRENGTHEN RAPIDLY AS IT ENCOUNTERS THE WARM SECTOR...CHARACTERIZED BY TEMPS IN THE UPPER 60S/LOWER 70S AND DEWPOINTS IN THE MID 60S...AND 500-1000 J/KG MLCAPE. THE WELL-TIMED ARRIVAL OF A DRY SLOT MAY ALSO HELP TO ENHANCE INSTABILITY...AS WELL AS DCAPE. LOW-LEVEL WINDS WILL HAVE VEERED TO MORE SOUTHERN BY THEN...BUT 0-3KM SRH WILL STILL BE 200-300 M2/S2 AND LONG HODOGRAPHS WILL SUPPORT BOWING LINE SEGMENTS AND SUPERCELLS. THE TIME FRAME FOR THIS APPEARS TO BETWEEN NOON AND 6PM. THE HRRR HAS REALLY LATCHED ONTO THIS IN THE PAST 3 OR 4 RUNS. SPC HAS UPGRADED A PORTION OF THE AREA TO A MODERATE RISK (FROM THE TRIANGLE NORTH AND EAST)...OWING TO THE BEST OVERLAP OF KINEMATICS AND EVENTUALLY DESTABILIZATION. DAMAGING WINDS WILL BE POSSIBLE FOR NEARLY ALL OF CENTRAL NC (POSSIBLY MISSING THE NORTHWEST PIEDMONT IF THEY DO NOT BREAK OUT PRIOR TO THE SECOND LINE OF CONVECTION) ...IF NOT FROM CONVECTION THEN FROM 20-25MPH WINDS AND GUSTS TO 40- 45MPH (ENHANCED EVEN BY SUB-SEVERE SHOWERS AND STORMS). A FEW TORNADOES ARE ALSO POSSIBLE AND A STRONG...LONG TRACK TORNADO CANNOT BE RULED OUT. THE CURRENT WIND ADVISORY WILL CONTINUE FROM 9AM THROUGH MIDNIGHT. THE CONVECTIVE LINE SHOULD RACE EAST OF THE AREA BY 8PM OR SO...WITH A FEW ADDITIONAL SHOWERS POSSIBLE ALONG THE MAIN COLD FRONT. LOWS WILL BOTTOM OUT IN THE41-48 RANGE. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 355 AM WEDNESDAY... SHORT WAVE ENERGY WILL CONTINUE TO ROTATE ACROSS THE OHIO VALLEY AROUND THE MAIN UPPER TROF THURSDAY AND THURSDAY NIGHT...WITH THE FINAL AND STRONGEST SHORT WAVE SHIFTING THE TROF AXIS OFFSHORE BY FRIDAY MORNING. MOISTURE WILL BE SQUEEZED OUT OVER THE WESTERN SLOPES...WITH SCATTERED TO BROKEN STRATOCUMULUS (PERHAPS A STRAY SPRINKLE OR TWO IN THE TRIAD) SPILLING ACROSS THE NORTHERN TIER. COLD AIR WILL BE REINFORCED...WITH A STRONG PRESSURE GRADIENT LINGERING THURSDAY FEATURING SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO AROUND 35 MPH...AND WITH A FEW INFREQUENT GUSTS INTO THE UPPER 30S TO NEAR 40S KTS POSSIBLE. HIGHS WILL BE A CATEGORY OR SO BELOW NORMAL...WITH THE AFOREMENTIONED BLUSTERY CONDITIONS AND AN ASSOCIATED CHILLIER FEEL THAN TEMPERATURES IN THE LOW TO MID 50S WOULD OTHERWISE SUGGEST. SKIES WILL BECOME CLEAR OVERNIGHT...WITH THE DIURNAL TEMPERATURE FALL TEMPERED BY GOOD MIXING TO KEEP FRIDAY MORNING MINS MOSTLY IN THE LOWER 30S. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 345 AM WEDNESDAY... COOL AIR ADVECTION DUE TO BROAD TROFFING ACROSS THE EASTERN CONUS WILL RESULT IN DRY WEATHER THROUGH THE WEEKEND...WITH HIGHS STRUGGLING TO REACH 50 ON BOTH FRIDAY AND SATURDAY. MORNING MINS WILL BE IN THE 30S SATURDAY AND SUNDAY MORNINGS. A FINAL MOISTURE STARVED SHORT WAVE WILL MOVE EAST ACROSS THE AREA LATER SATURDAY...INITIATING A SHORT-LIVED WARMING TREND THAT WILL BEGIN SUNDAY AS PROGRESSIVE SHORT WAVE RIDGING MOVES ACROSS CONCURRENT WITH MILD HIGH PRESSURE BUILDING IN FROM THE SOUTH. HIGHS SUNDAY WILL REACH NEAR NORMAL...MID TO UPPER 50S...AND REACH 60 TO 65 ON MONDAY AHEAD OF OUR NEXT DRY COLD FRONT WHICH WILL MOVE THROUGH LATER MONDAY TO COOL US BACK INTO THE MID AND UPPER 50S ON TUESDAY. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... AS OF 900 AM WEDNESDAY... COLD AIR DAMMING...AND ASSOCIATED COOL AND SATURATED AIR AND LIFR CONDITIONS TRAPPED BELOW A STRONG TEMPERATURE INVERSION CENTERED AROUND 2000-2500 FT...WILL CONTINUE UNTIL A WARM FRONT RETREATS NORTH THROUGH CENTRAL NC LATE THIS MORNING THROUGH MIDDAY. WINDS IN THE INVERSION LAYER WILL RAPIDLY STRENGTHEN BETWEEN 9-12Z...OWING TO THE APPROACH OF A POWERFUL UPPER LEVEL LOW FROM THE MID-SOUTH; AND THIS WILL RESULT IN THE OCCURRENCE OF LOW LEVEL WIND SHEAR UNTIL THE INVERSION BREAKS WITH THE PASSAGE OF THE WARM FRONT. THE WARM FRONT WILL MARK THE LEADING EDGE OF AN INCREASINGLY WINDY...WARM...AND HUMID REGIME --ONE CHARACTERIZED BY MVFR CEILINGS OR OCCASIONAL SCATTERING TO VFR-- AND STRONG SSE SURFACE WINDS BETWEEN 15-25 KTS WITH GUSTS OF 30-40 KTS. THE TIMING OF THE PASSAGE OF THIS WARM FRONT WILL LIKELY BE BETWEEN 11-14Z AT FAY AND RWI; 12-15Z AT RDU...AND 14-17Z AT GSO/INT. IN ADDITION...MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS WILL OVERSPREAD CENTRAL NC...THE FIRST OF WHICH IS NOW ABOUT TO CROSS THE SC STATE LINE. THESE INITIAL SHOWERS AND STORMS WILL BE BASED WITHIN THE AFOREMENTIONED INVERSION AND CONSEQUENTLY NOT POSE A RISK OF DAMAGING CONVECTIVE WINDS AND/OR TORNADOES. HOWEVER...SUBSEQUENT ROUNDS OF STORMS BETWEEN 15-22Z WILL LIKELY RESULT IN SWATHS OF STRAIGHT LINE WINDS IN EXCESS OF 70 MPH AND A FEW TORNADOES... PARTICULARLY AT RDU/FAY/RWI. A COLD FRONT WILL SWEEP THE STORMS AND SUB-VFR CONDITIONS EAST OF CENTRAL NC LATER THIS AFTERNOON AND EVENING. OUTLOOK: VFR CONDITIONS...BUT WITH BLUSTERY WESTERLY WINDS...WILL FOLLOW FOR TONIGHT AND ESPECIALLY THU. && .RAH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT EST TONIGHT FOR NCZ008>011-024>028-040>043-073>078-083>086-088-089. && $$ SYNOPSIS...26 NEAR TERM...22 SHORT TERM...26/MLM LONG TERM...MLM AVIATION...26
AREA FORECAST DISCUSSION
NWS RALEIGH NC
359 AM EST WED FEB 24 2016 .SYNOPSIS...A WARM FRONT WILL RETREAT NORTH TODAY...IN ADVANCE OF A POWERFUL UPPER LEVEL LOW AND ACCOMPANYING SURFACE CYCLONE THAT WILL TRACK THROUGH THE TN AND OH VALLEYS. A TRAILING COLD FRONT WILL SWEEP EAST ACROSS OUR REGION LATE THIS AFTERNOON AND EVENING. BLUSTERY CONDITIONS WILL FOLLOW AS HIGH PRESSURE BUILDS EAST TONIGHT AND THU. && .NEAR TERM /THROUGH TONIGHT/... AS OF 345 AM WEDNESDAY... ...STRONG WINDS AND SEVERE THUNDERSTORMS LIKELY TODAY... AN UPPER LEVEL TROUGH WILL SWING ACROSS THE SOUTHEAST STATES TODAY...WHILE THE ASSOCIATED JET STREAK STRENGTHENS FROM THE GULF COAST TOWARD THE CAROLINAS AND AN INTENSE LOW-LEVEL JET (60 KT AT 850MB AT KFFC) TRANSLATES ACROSS CENTRAL NC...ALL CONCURRENT WITH A STABILIZES AIRMASS IN THE WAKE OF AN INLAND RETREATING WEDGE/COASTAL WARM FRONTS. THIS WILL SET THE STAGE FOR A MULTIFACETED AND POTENTIALLY DANGEROUS SEVERE WEATHER SITUATION. GIVEN THE LARGE SCALE FORCING...IT APPEARS THERE WILL BE A COUPLE TIME PERIODS FAVORABLE FOR SEVERE WEATHER. THE FIRST WILL UNFOLD THIS MORNING (AND MAY ALREADY BE GETTING GOING WITH AN ELEVATED SUPERCELL APPROACHING RICHMOND COUNTY AT 3AM) AS WARM ADVECTION AND MUCAPE INCREASE ATOP THE STUBBORN WEDGE AIRMASS WHICH IS STILL NEAR THE COAST. THE WEDGE FRONT AND EVENTUALLY THE TRUE WARM SECTOR ARE PROGGED TO SLOWLY MIX INLAND THIS MORNING AND THEN MORE QUICKLY BY MIDDAY...WITH THE NORTHWEST PIEDMONT LIKELY TO BREAK OUT BY 2PM. MANY OF THE CAMS SHOW CONTINUED DEVELOPMENT OF CONVECTION TO OUR SOUTH THAT MOVES NORTH...AND WITH TIME SURFACE BASED CONVECTION WILL BE MORE LIKELY...WITH A GROWING CONCERN FOR THOSE STORMS INTERSECTING THE HELICITY LADEN WARM FRONT (0-3KM SRH OF 300-400 M2/S2). THE BEST TIME FRAME FOR THIS APPEARS TO BE FROM 5 AM THROUGH 11AM...MAINLY IN THE COASTAL PLAIN. AND THEN THIS AFTERNOON MODELS SEEM TO BE KEYING IN ON DEVELOPMENT FORCED BY THE MAIN UPPER TROUGH AND ALONG A CONFLUENCE ZONE (AHEAD OF THE MAIN COLD FRONT) THAT IS CURRENTLY OVER CENTRAL AL. THIS LINE WILL HAVE THE POTENTIAL TO STRENGTHEN RAPIDLY AS IT ENCOUNTERS THE WARM SECTOR...CHARACTERIZED BY TEMPS IN THE UPPER 60S/LOWER 70S AND DEWPOINTS IN THE MID 60S...AND 500-1000 J/KG MLCAPE. THE WELL-TIMED ARRIVAL OF A DRY SLOT MAY ALSO HELP TO ENHANCE INSTABILITY...AS WELL AS DCAPE. LOW-LEVEL WINDS WILL HAVE VEERED TO MORE SOUTHERN BY THEN...BUT 0-3KM SRH WILL STILL BE 200-300 M2/S2 AND LONG HODOGRAPHS WILL SUPPORT BOWING LINE SEGMENTS AND SUPERCELLS. THE TIME FRAME FOR THIS APPEARS TO BETWEEN NOON AND 6PM. THE HRRR HAS REALLY LATCHED ONTO THIS IN THE PAST 3 OR 4 RUNS. SPC HAS UPGRADED A PORTION OF THE AREA TO A MODERATE RISK (FROM THE TRIANGLE NORTH AND EAST)...OWING TO THE BEST OVERLAP OF KINEMATICS AND EVENTUALLY DESTABILIZATION. DAMAGING WINDS WILL BE POSSIBLE FOR NEARLY ALL OF CENTRAL NC (POSSIBLY MISSING THE NORTHWEST PIEDMONT IF THEY DO NOT BREAK OUT PRIOR TO THE SECOND LINE OF CONVECTION) ...IF NOT FROM CONVECTION THEN FROM 20-25MPH WINDS AND GUSTS TO 40- 45MPH (ENHANCED EVEN BY SUB-SEVERE SHOWERS AND STORMS). A FEW TORNADOES ARE ALSO POSSIBLE AND A STRONG...LONG TRACK TORNADO CANNOT BE RULED OUT. THE CURRENT WIND ADVISORY WILL CONTINUE FROM 9AM THROUGH MIDNIGHT. THE CONVECTIVE LINE SHOULD RACE EAST OF THE AREA BY 8PM OR SO...WITH A FEW ADDITIONAL SHOWERS POSSIBLE ALONG THE MAIN COLD FRONT. LOWS WILL BOTTOM OUT IN THE41-48 RANGE. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 355 AM WEDNESDAY... SHORT WAVE ENERGY WILL CONTINUE TO ROTATE ACROSS THE OHIO VALLEY AROUND THE MAIN UPPER TROF THURSDAY AND THURSDAY NIGHT...WITH THE FINAL AND STRONGEST SHORT WAVE SHIFTING THE TROF AXIS OFFSHORE BY FRIDAY MORNING. MOISTURE WILL BE SQUEEZED OUT OVER THE WESTERN SLOPES...WITH SCATTERED TO BROKEN STRATOCUMULUS (PERHAPS A STRAY SPRINKLE OR TWO IN THE TRIAD) SPILLING ACROSS THE NORTHERN TIER. COLD AIR WILL BE REINFORCED...WITH A STRONG PRESSURE GRADIENT LINGERING THURSDAY FEATURING SUSTAINED WESTERLY WINDS OF 15 TO 25 MPH WITH GUSTS TO AROUND 35 MPH...AND WITH A FEW INFREQUENT GUSTS INTO THE UPPER 30S TO NEAR 40S KTS POSSIBLE. HIGHS WILL BE A CATEGORY OR SO BELOW NORMAL...WITH THE AFOREMENTIONED BLUSTERY CONDITIONS AND AN ASSOCIATED CHILLIER FEEL THAN TEMPERATURES IN THE LOW TO MID 50S WOULD OTHERWISE SUGGEST. SKIES WILL BECOME CLEAR OVERNIGHT...WITH THE DIURNAL TEMPERATURE FALL TEMPERED BY GOOD MIXING TO KEEP FRIDAY MORNING MINS MOSTLY IN THE LOWER 30S. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 345 AM WEDNESDAY... COOL AIR ADVECTION DUE TO BROAD TROFFING ACROSS THE EASTERN CONUS WILL RESULT IN DRY WEATHER THROUGH THE WEEKEND...WITH HIGHS STRUGGLING TO REACH 50 ON BOTH FRIDAY AND SATURDAY. MORNING MINS WILL BE IN THE 30S SATURDAY AND SUNDAY MORNINGS. A FINAL MOISTURE STARVED SHORT WAVE WILL MOVE EAST ACROSS THE AREA LATER SATURDAY...INITIATING A SHORT-LIVED WARMING TREND THAT WILL BEGIN SUNDAY AS PROGRESSIVE SHORT WAVE RIDGING MOVES ACROSS CONCURRENT WITH MILD HIGH PRESSURE BUILDING IN FROM THE SOUTH. HIGHS SUNDAY WILL REACH NEAR NORMAL...MID TO UPPER 50S...AND REACH 60 TO 65 ON MONDAY AHEAD OF OUR NEXT DRY COLD FRONT WHICH WILL MOVE THROUGH LATER MONDAY TO COOL US BACK INTO THE MID AND UPPER 50S ON TUESDAY. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... AS OF 200 AM WEDNESDAY... COLD AIR DAMMING...AND ASSOCIATED COOL AND SATURATED AIR AND LIFR CONDITIONS TRAPPED BELOW A STRONG TEMPERATURE INVERSION CENTERED AROUND 2000-2500 FT...WILL CONTINUE UNTIL A WARM FRONT RETREATS NORTH THROUGH CENTRAL NC LATE THIS MORNING THROUGH MIDDAY. WINDS IN THE INVERSION LAYER WILL RAPIDLY STRENGTHEN BETWEEN 9-12Z...OWING TO THE APPROACH OF A POWERFUL UPPER LEVEL LOW FROM THE MID-SOUTH; AND THIS WILL RESULT IN THE OCCURRENCE OF LOW LEVEL WIND SHEAR UNTIL THE INVERSION BREAKS WITH THE PASSAGE OF THE WARM FRONT. THE WARM FRONT WILL MARK THE LEADING EDGE OF AN INCREASINGLY WINDY...WARM...AND HUMID REGIME --ONE CHARACTERIZED BY MVFR CEILINGS OR OCCASIONAL SCATTERING TO VFR-- AND STRONG SSE SURFACE WINDS BETWEEN 15-25 KTS WITH GUSTS OF 30-40 KTS. THE TIMING OF THE PASSAGE OF THIS WARM FRONT WILL LIKELY BE BETWEEN 11-14Z AT FAY AND RWI; 12-15Z AT RDU...AND 14-17Z AT GSO/INT. IN ADDITION...MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS WILL OVERSPREAD CENTRAL NC...THE FIRST OF WHICH IS NOW ABOUT TO CROSS THE SC STATE LINE. THESE INITIAL SHOWERS AND STORMS WILL BE BASED WITHIN THE AFOREMENTIONED INVERSION AND CONSEQUENTLY NOT POSE A RISK OF DAMAGING CONVECTIVE WINDS AND/OR TORNADOES. HOWEVER...SUBSEQUENT ROUNDS OF STORMS BETWEEN 15-22Z WILL LIKELY RESULT IN SWATHS OF STRAIGHT LINE WINDS IN EXCESS OF 70 MPH AND A FEW TORNADOES... PARTICULARLY AT RDU/FAY/RWI. A COLD FRONT WILL SWEEP THE STORMS AND SUB-VFR CONDITIONS EAST OF CENTRAL NC LATER THIS AFTERNOON AND EVENING. OUTLOOK: VFR CONDITIONS...BUT WITH BLUSTERY WESTERLY WINDS...WILL FOLLOW FOR TONIGHT AND ESPECIALLY THU. && .RAH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT EST TONIGHT FOR NCZ008>011-024>028-040>043-073>078-083>086-088-089. && $$ SYNOPSIS...26 NEAR TERM...22 SHORT TERM...26/MLM LONG TERM...MLM AVIATION...26
AREA FORECAST DISCUSSION
NWS RALEIGH NC
345 AM EST WED FEB 24 2016 .SYNOPSIS...A WARM FRONT WILL RETREAT NORTH TODAY...IN ADVANCE OF A POWERFUL UPPER LEVEL LOW AND ACCOMPANYING SURFACE CYCLONE THAT WILL TRACK THROUGH THE TN AND OH VALLEYS. A TRAILING COLD FRONT WILL SWEEP EAST ACROSS OUR REGION LATE THIS AFTERNOON AND EVENING. BLUSTERY CONDITIONS WILL FOLLOW AS HIGH PRESSURE BUILDS EAST TONIGHT AND THU. && .NEAR TERM /THROUGH TONIGHT/... AS OF 345 AM WEDNESDAY... ...STRONG WINDS AND SEVERE THUNDERSTORMS LIKELY TODAY... AN UPPER LEVEL TROUGH WILL SWING ACROSS THE SOUTHEAST STATES TODAY...WHILE THE ASSOCIATED JET STREAK STRENGTHENS FROM THE GULF COAST TOWARD THE CAROLINAS AND AN INTENSE LOW-LEVEL JET (60 KT AT 850MB AT KFFC) TRANSLATES ACROSS CENTRAL NC...ALL CONCURRENT WITH A STABILIZES AIRMASS IN THE WAKE OF AN INLAND RETREATING WEDGE/COASTAL WARM FRONTS. THIS WILL SET THE STAGE FOR A MULTIFACETED AND POTENTIALLY DANGEROUS SEVERE WEATHER SITUATION. GIVEN THE LARGE SCALE FORCING...IT APPEARS THERE WILL BE A COUPLE TIME PERIODS FAVORABLE FOR SEVERE WEATHER. THE FIRST WILL UNFOLD THIS MORNING (AND MAY ALREADY BE GETTING GOING WITH AN ELEVATED SUPERCELL APPROACHING RICHMOND COUNTY AT 3AM) AS WARM ADVECTION AND MUCAPE INCREASE ATOP THE STUBBORN WEDGE AIRMASS WHICH IS STILL NEAR THE COAST. THE WEDGE FRONT AND EVENTUALLY THE TRUE WARM SECTOR ARE PROGGED TO SLOWLY MIX INLAND THIS MORNING AND THEN MORE QUICKLY BY MIDDAY...WITH THE NORTHWEST PIEDMONT LIKELY TO BREAK OUT BY 2PM. MANY OF THE CAMS SHOW CONTINUED DEVELOPMENT OF CONVECTION TO OUR SOUTH THAT MOVES NORTH...AND WITH TIME SURFACE BASED CONVECTION WILL BE MORE LIKELY...WITH A GROWING CONCERN FOR THOSE STORMS INTERSECTING THE HELICITY LADEN WARM FRONT (0-3KM SRH OF 300-400 M2/S2). THE BEST TIME FRAME FOR THIS APPEARS TO BE FROM 5 AM THROUGH 11AM...MAINLY IN THE COASTAL PLAIN. AND THEN THIS AFTERNOON MODELS SEEM TO BE KEYING IN ON DEVELOPMENT FORCED BY THE MAIN UPPER TROUGH AND ALONG A CONFLUENCE ZONE (AHEAD OF THE MAIN COLD FRONT) THAT IS CURRENTLY OVER CENTRAL AL. THIS LINE WILL HAVE THE POTENTIAL TO STRENGTHEN RAPIDLY AS IT ENCOUNTERS THE WARM SECTOR...CHARACTERIZED BY TEMPS IN THE UPPER 60S/LOWER 70S AND DEWPOINTS IN THE MID 60S...AND 500-1000 J/KG MLCAPE. THE WELL-TIMED ARRIVAL OF A DRY SLOT MAY ALSO HELP TO ENHANCE INSTABILITY...AS WELL AS DCAPE. LOW-LEVEL WINDS WILL HAVE VEERED TO MORE SOUTHERN BY THEN...BUT 0-3KM SRH WILL STILL BE 200-300 M2/S2 AND LONG HODOGRAPHS WILL SUPPORT BOWING LINE SEGMENTS AND SUPERCELLS. THE TIME FRAME FOR THIS APPEARS TO BETWEEN NOON AND 6PM. THE HRRR HAS REALLY LATCHED ONTO THIS IN THE PAST 3 OR 4 RUNS. SPC HAS UPGRADED A PORTION OF THE AREA TO A MODERATE RISK (FROM THE TRIANGLE NORTH AND EAST)...OWING TO THE BEST OVERLAP OF KINEMATICS AND EVENTUALLY DESTABILIZATION. DAMAGING WINDS WILL BE POSSIBLE FOR NEARLY ALL OF CENTRAL NC (POSSIBLY MISSING THE NORTHWEST PIEDMONT IF THEY DO NOT BREAK OUT PRIOR TO THE SECOND LINE OF CONVECTION) ...IF NOT FROM CONVECTION THEN FROM 20-25MPH WINDS AND GUSTS TO 40- 45MPH (ENHANCED EVEN BY SUB-SEVERE SHOWERS AND STORMS). A FEW TORNADOES ARE ALSO POSSIBLE AND A STRONG...LONG TRACK TORNADO CANNOT BE RULED OUT. THE CURRENT WIND ADVISORY WILL CONTINUE FROM 9AM THROUGH MIDNIGHT. THE CONVECTIVE LINE SHOULD RACE EAST OF THE AREA BY 8PM OR SO...WITH A FEW ADDITIONAL SHOWERS POSSIBLE ALONG THE MAIN COLD FRONT. LOWS WILL BOTTOM OUT IN THE41-48 RANGE. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 340 PM TUESDAY... ...STRONG WIND GUSTS IN ADDITION TO A RISK OF SEVERE THUNDERSTORMS EXPECTED WEDNESDAY... THE STRONG LOW PRESSURE SYSTEM RESPONSIBLE FOR THE SEVERE WEATHER THIS AFTERNOON ACROSS THE LOWER MISSISSIPPI VALLEY WILL LIFT NEWD THROUGH THE TN-LOWER OH VALLEY ON WEDNESDAY. STRONG WINDS ROTATING AROUND THE BASE OF THE ASSOCIATED UPPER TROUGH WILL CROSS CENTRAL NC ON WEDNESDAY. THE STRENGTH/DEPTH OF THE SURFACE LOW (SUB 990MB) AND AN AREA OF HIGH PRESSURE OFFSHORE WILL CAUSE VERY WINDY CONDITIONS. THESE STRONG SLY SF WINDS WILL AID TO SCOUR OUT THE RESIDUAL CAD AIR MASS DURING THE MORNING HOURS. SLY SUSTAINED WINDS IN THE WARM SECTOR AROUND 20 MPH WILL BE COMMON WITH GUSTS 35-40MPH LIKELY...ESPECIALLY ALONG AND EAST OF HIGHWAY 1. WINDS OF THIS MAGNITUDE EXPECTED TO OCCUR FOR A SOLID 9-12 HOURS. THUS PLAN TO ISSUE A WIND ADVISORY FOR MOST OF CENTRAL NC (EXCLUDING THE NW PIEDMONT) FOR MOST OF WEDNESDAY INTO WEDNESDAY EVENING. THE SLY WINDS WILL USHER A MOIST SLIGHTLY UNSTABLE AIR MASS INTO CENTRAL NC. NEAR SURFACE S-SE WINDS COUPLED WITH A SLY LOW LEVEL JET UPWARDS 50-60KTS WILL CREATE A HIGHLY SHEARED ENVIRONMENT EVIDENT BY THE LARGE TURN HODOGRAPHS. WHILE KINEMATICS ARE QUITE STRONG...LOW LEVEL INSTABILITY CHARACTERIZED AS SLIGHT AT BEST. STILL...CONSIDERING THE TIME OF YEAR...THE STRENGTH OF THE KINEMATICS MAY COMPENSATE FOR THE LACK OF MODERATE-STRONGLY UNSTABLE AIR MASS. THE BETTER SUPPORT FOR DEEP CONVECTION WILL CROSS CENTRAL NC MID- LATE MORNING THROUGH THE LATE AFTERNOON HOURS. LATEST RUN OF WRF MODELS AND CONVECTIVE ALLOWING MODELS ARE HINTING AT THE POSSIBILITY OF TWO LINES OF CONVECTION CROSSING THE REGION...THE FIRST IN THE LATE MORNING THROUGH EARLY-MID AFTERNOON...AND ANOTHER CROSSING THE PIEDMONT COUNTIES LATE AFTERNOON-EARLY EVENING. THE KINEMATICS SUPPORT THE POTENTIAL FOR THE DEVELOPMENT OF A FEW STORMS WITH SUPERCELLULAR CHARACTERISTICS. THIS POTENTIAL LOOKS BEST OVER THE SANDHILLS AND THE COASTAL PLAIN WHERE THE BEST INSTABILITY. ELSEWHERE...STRONG DAMAGING WIND GUSTS WILL BE LIKELY WITH ANY STRONG/SEVERE STORMS THAT OCCUR. NOT OUT OF THE REALM OF POSSIBILITY THAT WIND GUSTS AROUND 70 MPH WILL OCCUR. WHILE CONFIDENCE IS FAIRLY CERTAIN THAT SEVERE STORMS ARE POSSIBLE OVER MOST OF CENTRAL NC...WITH THE MOST FAVORABLE CONDITIONS EAST OF HIGHWAY 1...THE THREAT FOR SEVERE STORMS IN VICINITY OF THE TRIAD IS A LITTLE BIT UNCERTAIN. THE MODELS WHAT TO QUICKLY SCOUR OUT THE RESIDUAL CAD AIR MASS OVER THE TRIAD BUT CONSIDERING HOW ENTRENCHED THE CAD IS PRESENTLY...THE EFFECTS OF THE CAD MAY LINGER LONGER...LIMITING THE ABILITY OF THE STRONG/DAMAGING WINDS FROM REACHING THE SURFACE. THUS...WHILE THE RESIDUAL CAD MAY INITIALLY PROTECT THE TRIAD WHEN THE INITIAL LINE OF CONVECTION MOVES IN LATE MORNING...THE SECOND LINE (IF IT FORMS) MAY HAVE BETTER POTENTIAL TO PRODUCE DAMAGING WINDS IN THE TRIAD LATER IN THE DAY. A MAY STABLE DIRE AIR MASS WILL OVERSPREAD CENTRAL NC WEDNESDAY EVENING-WEDNESDAY NIGHT...AIDING TO DISSIPATE REMAINING SHOWERS AND STORMS AND CLEARING SKIES WEST-TO-EAST. IT WILL REMAIN WINDY WITH GUSTS 20-30 MPH EXPECTED... IN THE EAST. && .LONG TERM /THURSDAY THROUGH TUESDAY/... AS OF 1245 PM TUESDAY... SHORT WAVE ENERGY WILL CONTINUE TO ROTATE ACROSS THE OHIO VALLEY AROUND THE MAIN UPPER TROF THURSDAY AND THURSDAY NIGHT...WITH THE FINAL AND STRONGEST SHORT WAVE SHIFTING THE TROF AXIS OFFSHORE BY FRIDAY MORNING. MOISTURE WILL BE SQUEEZED OUT OVER THE WESTERN SLOPES...WITH SCATTERED TO BROKEN STRATOCUMULUS (PERHAPS A STRAY SPRINKLE OR TWO IN THE TRIAD) SPILLING ACROSS THE NORTHERN TIER. COLD AIR WILL BE REINFORCED...WITH A STRONG PRESSURE GRADIENT LINGERING THURSDAY FEATURING SUSTAINED WESTERLY WINDS OF 15 TO 20 MPH WITH GUSTS TO 30 MPH. HIGHS WILL BE A CATEGORY OR SO BELOW NORMAL THURSDAY...A WINDY AND CHILLY 50 TO 55. SKIES WILL BECOME CLEAR OVERNIGHT...WITH THE DIURNAL TEMPERATURE FALL TEMPERED BY GOOD MIXING TO KEEP FRIDAY MORNING MINS MOSTLY IN THE LOWER 30S. COOL AIR ADVECTION DUE TO BROAD TROFFING ACROSS THE EASTERN CONUS WILL RESULT IN DRY WEATHER THROUGH THE WEEKEND...WITH HIGHS STRUGGLING TO REACH 50 ON BOTH FRIDAY AND SATURDAY. MORNING MINS WILL BE IN THE 30S SATURDAY AND SUNDAY MORNINGS. A FINAL MOISTURE STARVED SHORT WAVE WILL MOVE EAST ACROSS THE AREA LATER SATURDAY...INITIATING A SHORT-LIVED WARMING TREND THAT WILL BEGIN SUNDAY AS PROGRESSIVE SHORT WAVE RIDGING MOVES ACROSS CONCURRENT WITH MILD HIGH PRESSURE BUILDING IN FROM THE SOUTH. HIGHS SUNDAY WILL REACH NEAR NORMAL...MID TO UPPER 50S...AND REACH 60 TO 65 ON MONDAY AHEAD OF OUR NEXT DRY COLD FRONT WHICH WILL MOVE THROUGH LATER MONDAY TO COOL US BACK INTO THE MID AND UPPER 50S ON TUESDAY. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... AS OF 200 AM WEDNESDAY... COLD AIR DAMMING...AND ASSOCIATED COOL AND SATURATED AIR AND LIFR CONDITIONS TRAPPED BELOW A STRONG TEMPERATURE INVERSION CENTERED AROUND 2000-2500 FT...WILL CONTINUE UNTIL A WARM FRONT RETREATS NORTH THROUGH CENTRAL NC LATE THIS MORNING THROUGH MIDDAY. WINDS IN THE INVERSION LAYER WILL RAPIDLY STRENGTHEN BETWEEN 9-12Z...OWING TO THE APPROACH OF A POWERFUL UPPER LEVEL LOW FROM THE MID-SOUTH; AND THIS WILL RESULT IN THE OCCURRENCE OF LOW LEVEL WIND SHEAR UNTIL THE INVERSION BREAKS WITH THE PASSAGE OF THE WARM FRONT. THE WARM FRONT WILL MARK THE LEADING EDGE OF AN INCREASINGLY WINDY...WARM...AND HUMID REGIME --ONE CHARACTERIZED BY MVFR CEILINGS OR OCCASIONAL SCATTERING TO VFR-- AND STRONG SSE SURFACE WINDS BETWEEN 15-25 KTS WITH GUSTS OF 30-40 KTS. THE TIMING OF THE PASSAGE OF THIS WARM FRONT WILL LIKELY BE BETWEEN 11-14Z AT FAY AND RWI; 12-15Z AT RDU...AND 14-17Z AT GSO/INT. IN ADDITION...MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS WILL OVERSPREAD CENTRAL NC...THE FIRST OF WHICH IS NOW ABOUT TO CROSS THE SC STATE LINE. THESE INITIAL SHOWERS AND STORMS WILL BE BASED WITHIN THE AFOREMENTIONED INVERSION AND CONSEQUENTLY NOT POSE A RISK OF DAMAGING CONVECTIVE WINDS AND/OR TORNADOES. HOWEVER...SUBSEQUENT ROUNDS OF STORMS BETWEEN 15-22Z WILL LIKELY RESULT IN SWATHS OF STRAIGHT LINE WINDS IN EXCESS OF 70 MPH AND A FEW TORNADOES... PARTICULARLY AT RDU/FAY/RWI. A COLD FRONT WILL SWEEP THE STORMS AND SUB-VFR CONDITIONS EAST OF CENTRAL NC LATER THIS AFTERNOON AND EVENING. OUTLOOK: VFR CONDITIONS...BUT WITH BLUSTERY WESTERLY WINDS...WILL FOLLOW FOR TONIGHT AND ESPECIALLY THU. && .RAH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT EST TONIGHT FOR NCZ008>011-024>028-040>043-073>078-083>086-088-089. && $$ SYNOPSIS...26 NEAR TERM...22 SHORT TERM...WSS LONG TERM...MLM AVIATION...26
AREA FORECAST DISCUSSION
NWS BISMARCK ND
939 PM CST THU FEB 25 2016 .UPDATE... ISSUED AT 939 PM CST THU FEB 25 2016 MID- AND HIGH-LEVEL CLOUD COVER IS HELPING PREVENT FREE-FALLING TEMPERATURES THIS EVENING DESPITE A BOUNDARY LAYER. WE HELD WITH PREVIOUS FORECAST LOWS FOR NOW EVEN THOUGH RECENT HIGH-RESOLUTION MODEL GUIDANCE KEYS ON THE CLOUD COVER AND ACTUALLY SUGGESTS LOWS WARMER THAN WE ARE ADVERTISING. OUR DECISION TO MAKE NO CHANGE TO OFFICIALLY-FORECAST LOWS IS BASED ON THE DRY AIR AND THE CLEARING ALREADY ADVANCING SOUTHEASTWARD ACROSS NORTHWEST ND PER EVENING SATELLITE IMAGERY. IN THE MEANTIME WE DID NEED TO INCREASE CLOUD COVER IN THE FORECAST...WHILE ADVERTISING A DECREASE OVERNIGHT. UPDATE ISSUED AT 554 PM CST THU FEB 25 2016 NO CHANGES OF NOTE WERE MADE WITH THIS UPDATE. LATE AFTERNOON MOISTURE CHANNEL IMAGES SHOW A SHORTWAVE TROUGH DROPPING SOUTH- EAST ACROSS SASKATCHEWAN. THAT WAVE IS RESPONSIBLE FOR THE HIGH- LEVEL CLOUDS ACROSS THE AREA...BUT MODEL GUIDANCE IS STILL VERY SUPPORTIVE OF A DRY AND QUIET NIGHT DESPITE THAT WAVE PASSAGE. THAT/S LARGELY DUE TO THE VERY DRY AIR MASS THAT EXISTS WITH 23 UTC SURFACE DEWPOINTS RANGING FROM THE SINGLE DIGITS F IN SOUTH- WEST ND TO THE TEENS F ELSEWHERE. THE DRY AIR MAY PROMOTE QUICK COOLING THIS EVENING SO WE WILL HAVE TO MONITOR TEMPERATURES IN CASE FORECAST LOWS ARE TOO OPTIMISTIC. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 129 PM CST THU FEB 25 2016 LATE THURSDAY AFTERNOON...A REGION OF SURFACE HIGH PRESSURE EXTENDED FROM THE SOUTHERN PROVINCES OF MANITOBA/SASKATCHEWAN SOUTH THROUGH THE CENTRAL PLAINS. STRATUS CLOUDS WERE RETREATING TO THE EAST AS LOW LEVEL WARM AIR ADVECTION WAS ERODING THE WESTERN EDGE. BY THIS EVENING THE STRATUS SHOULD HAVE RETREATED EAST OF THE JAMES RIVER VALLEY IN RESPONSE TO A WEST TO NORTHWEST WARM ADVECTIVE FLOW. THE HRRR DOES HINT AT SOME ISOLATED FOG NORTH CENTRAL BUT NOT ENOUGH SIGNAL TO PUT THAT IN THE FORECAST YET. ON FRIDAY...THE H500 RIDGE MOVES EAST TO THE CENTRAL AND NORTHERN PLAINS WITH BROAD WARM ADVECTION. WITH SUNNY SKIES FRIDAYS HIGHS WILL BE WELL INTO THE 50S WEST AND CENTRAL...WITH MID TO UPPER 40S JAMES RIVER VALLEY NORTH TO THE TURTLE MOUNTAINS. WITH GOOD MIXING HAVE RAISED MAX TEMPS 1 TO 2 DEGREES ABOVE THE CONSSHORT GUIDANCE FOR FRIDAY. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 129 PM CST THU FEB 25 2016 AN ACTIVE LONG TERM PERIOD. MAIN HIGHLIGHTS ARE A BRIEF BUT SIGNIFICANT WARMUP SATURDAY...FOLLOWED BY SUCCESSIVE COLD FRONTS ROUNDING OUT THE WEEKEND INTO EARLY NEXT WEEK PROMOTING A COOLING TREND. CHANCES OF SNOW ALSO RETURN WITH EACH SYSTEM THAT MOVES THROUGH. FRIDAY NIGHT THROUGH SATURDAY...WESTERN AND CENTRAL NORTH DAKOTA RESIDES IN THE WARM SECTOR. THE NAEFS/NORTH AMERICAN ENSEMBLE FORECAST SYSTEM SHOWS MODEL FORECASTS WITH REGARDS TO 850-500MB TEMPERATURES FALLING WITHIN THE 98TH/99TH PERCENTILE WITH RESPECT TO CLIMATOLOGY. NOT QUITE A MAXIMUM BUT CLOSE ENOUGH TO WHERE THESE ENSEMBLE TEMPERATURES REPRESENT AN EVENT THAT IS OUTSIDE THE 1979- 2000 CLIMATOLOGY FOR THIS TIME OF YEAR. RECORD HIGHS SATURDAY ARE AROUND 65 DEGREES FOR MOST OF THE MAJOR CITIES WITH THE RECORD AT JAMESTOWN OF 60 DEGREES. FORECAST HIGHS WILL MOSTLY RANGE BETWEEN 50F AND 62F. ALBEIT SHY OF RECORDS...THIS WILL STILL NEED SOME MONITORING AS WE GET CLOSER. A SURFACE COLD FRONT IMPINGES UPON NORTHWEST NORTH DAKOTA SATURDAY AFTERNOON WITH COLD AIR ADVECTION DEVELOPING. THIS COLD FRONT WILL SWEEP THROUGH ALL OF WESTERN AND CENTRAL NORTH DAKOTA SATURDAY NIGHT. A SLIGHT CHANCE OF RAIN SHOWERS IS FORECAST WEST SATURDAY EVENING...AND AS COLDER AIR ARRIVES SATURDAY NIGHT...EXPECT ANY PRECIPITATION TO CHANGE OVER TO LIGHT SNOW SHOWERS SATURDAY NIGHT. SUNDAY THROUGH TUESDAY...A QUICK TRANSITION FROM COLD AIR ADVECTION TO WARM AIR ADVECTION SUNDAY EVENING...THEN BACK TO COLD AIR ADVECTION SUNDAY NIGHT AND MONDAY AS AN ALBERTA CLIPPER PUSHES THROUGH. THE GFS AND ECMWF SHOW ANOTHER SHORTWAVE AND SURFACE LOW TO FOLLOW ON MONDAY. THIS SHORTWAVE MOVES FROM EASTERN MONTANA INTO WESTERN AND SOUTHERN NORTH DAKOTA MONDAY AFTERNOON THROUGH MONDAY NIGHT. CURRENTLY THE LONG TERM FORECAST GRIDS ONLY CARRY A SLIGHT CHANCE OF SNOW. THIS COULD CHANGE IF AGREEMENT AMONGST THE LONG TERM MODELS CONTINUE. TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...THE SYSTEM DEPARTS TUESDAY NIGHT WITH THE NEXT ONE COMING ACROSS WEDNESDAY INTO WEDNESDAY NIGHT. THE ECMWF IS STRONGER WITH PRECIPITATION CHANCES THAN THE GFS DURING THIS TIME PERIOD. THE SUPERBLEND CURRENTLY ADVERTISES CHANCES OF SNOW IN THE TURTLE MOUNTAINS ONLY. TEMPERATURES THROUGH AFTER SATURDAY IN THE LONG TERM PERIOD WILL TREND COOLER. HIGHS IN THE 40S SUNDAY WILL FALL BACK INTO THE 30S FOR THE MOST PART MONDAY THROUGH THURSDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 939 PM CST THU FEB 25 2016 GOOD VFR FLYING WEATHER IS EXPECTED TONIGHT AND FRIDAY ACROSS WESTERN AND CENTRAL ND WITH ONLY SOME PASSING MID- AND HIGH-LEVEL CLOUDS THANKS TO A DRY AIR MASS WITH HIGH PRESSURE MAINLY IN CONTROL. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CJS SHORT TERM...WAA LONG TERM...KS AVIATION...CJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
554 PM CST THU FEB 25 2016 .UPDATE... ISSUED AT 554 PM CST THU FEB 25 2016 NO CHANGES OF NOTE WERE MADE WITH THIS UPDATE. LATE AFTERNOON MOISTURE CHANNEL IMAGES SHOW A SHORTWAVE TROUGH DROPPING SOUTH- EAST ACROSS SASKATCHEWAN. THAT WAVE IS RESPONSIBLE FOR THE HIGH- LEVEL CLOUDS ACROSS THE AREA...BUT MODEL GUIDANCE IS STILL VERY SUPPORTIVE OF A DRY AND QUIET NIGHT DESPITE THAT WAVE PASSAGE. THAT/S LARGELY DUE TO THE VERY DRY AIR MASS THAT EXISTS WITH 23 UTC SURFACE DEWPOINTS RANGING FROM THE SINGLE DIGITS F IN SOUTH- WEST ND TO THE TEENS F ELSEWHERE. THE DRY AIR MAY PROMOTE QUICK COOLING THIS EVENING SO WE WILL HAVE TO MONITOR TEMPERATURES IN CASE FORECAST LOWS ARE TOO OPTIMISTIC. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 129 PM CST THU FEB 25 2016 LATE THURSDAY AFTERNOON...A REGION OF SURFACE HIGH PRESSURE EXTENDED FROM THE SOUTHERN PROVINCES OF MANITOBA/SASKATCHEWAN SOUTH THROUGH THE CENTRAL PLAINS. STRATUS CLOUDS WERE RETREATING TO THE EAST AS LOW LEVEL WARM AIR ADVECTION WAS ERODING THE WESTERN EDGE. BY THIS EVENING THE STRATUS SHOULD HAVE RETREATED EAST OF THE JAMES RIVER VALLEY IN RESPONSE TO A WEST TO NORTHWEST WARM ADVECTIVE FLOW. THE HRRR DOES HINT AT SOME ISOLATED FOG NORTH CENTRAL BUT NOT ENOUGH SIGNAL TO PUT THAT IN THE FORECAST YET. ON FRIDAY...THE H500 RIDGE MOVES EAST TO THE CENTRAL AND NORTHERN PLAINS WITH BROAD WARM ADVECTION. WITH SUNNY SKIES FRIDAYS HIGHS WILL BE WELL INTO THE 50S WEST AND CENTRAL...WITH MID TO UPPER 40S JAMES RIVER VALLEY NORTH TO THE TURTLE MOUNTAINS. WITH GOOD MIXING HAVE RAISED MAX TEMPS 1 TO 2 DEGREES ABOVE THE CONSSHORT GUIDANCE FOR FRIDAY. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 129 PM CST THU FEB 25 2016 AN ACTIVE LONG TERM PERIOD. MAIN HIGHLIGHTS ARE A BRIEF BUT SIGNIFICANT WARMUP SATURDAY...FOLLOWED BY SUCCESSIVE COLD FRONTS ROUNDING OUT THE WEEKEND INTO EARLY NEXT WEEK PROMOTING A COOLING TREND. CHANCES OF SNOW ALSO RETURN WITH EACH SYSTEM THAT MOVES THROUGH. FRIDAY NIGHT THROUGH SATURDAY...WESTERN AND CENTRAL NORTH DAKOTA RESIDES IN THE WARM SECTOR. THE NAEFS/NORTH AMERICAN ENSEMBLE FORECAST SYSTEM SHOWS MODEL FORECASTS WITH REGARDS TO 850-500MB TEMPERATURES FALLING WITHIN THE 98TH/99TH PERCENTILE WITH RESPECT TO CLIMATOLOGY. NOT QUITE A MAXIMUM BUT CLOSE ENOUGH TO WHERE THESE ENSEMBLE TEMPERATURES REPRESENT AN EVENT THAT IS OUTSIDE THE 1979- 2000 CLIMATOLOGY FOR THIS TIME OF YEAR. RECORD HIGHS SATURDAY ARE AROUND 65 DEGREES FOR MOST OF THE MAJOR CITIES WITH THE RECORD AT JAMESTOWN OF 60 DEGREES. FORECAST HIGHS WILL MOSTLY RANGE BETWEEN 50F AND 62F. ALBEIT SHY OF RECORDS...THIS WILL STILL NEED SOME MONITORING AS WE GET CLOSER. A SURFACE COLD FRONT IMPINGES UPON NORTHWEST NORTH DAKOTA SATURDAY AFTERNOON WITH COLD AIR ADVECTION DEVELOPING. THIS COLD FRONT WILL SWEEP THROUGH ALL OF WESTERN AND CENTRAL NORTH DAKOTA SATURDAY NIGHT. A SLIGHT CHANCE OF RAIN SHOWERS IS FORECAST WEST SATURDAY EVENING...AND AS COLDER AIR ARRIVES SATURDAY NIGHT...EXPECT ANY PRECIPITATION TO CHANGE OVER TO LIGHT SNOW SHOWERS SATURDAY NIGHT. SUNDAY THROUGH TUESDAY...A QUICK TRANSITION FROM COLD AIR ADVECTION TO WARM AIR ADVECTION SUNDAY EVENING...THEN BACK TO COLD AIR ADVECTION SUNDAY NIGHT AND MONDAY AS AN ALBERTA CLIPPER PUSHES THROUGH. THE GFS AND ECMWF SHOW ANOTHER SHORTWAVE AND SURFACE LOW TO FOLLOW ON MONDAY. THIS SHORTWAVE MOVES FROM EASTERN MONTANA INTO WESTERN AND SOUTHERN NORTH DAKOTA MONDAY AFTERNOON THROUGH MONDAY NIGHT. CURRENTLY THE LONG TERM FORECAST GRIDS ONLY CARRY A SLIGHT CHANCE OF SNOW. THIS COULD CHANGE IF AGREEMENT AMONGST THE LONG TERM MODELS CONTINUE. TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...THE SYSTEM DEPARTS TUESDAY NIGHT WITH THE NEXT ONE COMING ACROSS WEDNESDAY INTO WEDNESDAY NIGHT. THE ECMWF IS STRONGER WITH PRECIPITATION CHANCES THAN THE GFS DURING THIS TIME PERIOD. THE SUPERBLEND CURRENTLY ADVERTISES CHANCES OF SNOW IN THE TURTLE MOUNTAINS ONLY. TEMPERATURES THROUGH AFTER SATURDAY IN THE LONG TERM PERIOD WILL TREND COOLER. HIGHS IN THE 40S SUNDAY WILL FALL BACK INTO THE 30S FOR THE MOST PART MONDAY THROUGH THURSDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 554 PM CST THU FEB 25 2016 GOOD VFR FLYING WEATHER IS EXPECTED TONIGHT AND FRIDAY ACROSS WESTERN AND CENTRAL ND WITH ONLY SOME PASSING HIGH-LEVEL CLOUDS THANKS TO A DRY AIR MASS WITH HIGH PRESSURE MAINLY IN CONTROL. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CJS SHORT TERM...WAA LONG TERM...KS AVIATION...CJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1255 AM CST WED FEB 24 2016 .UPDATE... ISSUED AT 1255 AM CST WED FEB 24 2016 STRONG S/WV TROUGH/CLIPPER SYSTEM OVER SOUTHERN SASKATCHEWAN ADVANCING SOUTHEAST TOWARDS NORTH DAKOTA. THIS FEATURE WILL TRACK INTO WESTERN NORTH DAKOTA OVERNIGHT...THEN SOUTH-SOUTHEAST ACROSS THE DAKOTAS WEDNESDAY AND WEDNESDAY NIGHT. AREA OF LIGHT SNOW WILL TRACK FROM EASTERN MONTANA INTO WEST CENTRAL AND SOUTHWESTERN ND NOW THROUGH 12Z...THEN INTO PORTIONS OF THE SOUTH CENTRAL 12-18Z. MODELS ARE TRYING TO PORTRAY A LULL IN PRECIPITATION BEHIND THIS INITIAL AREA OF LIGHT SNOW...AND HARD TO ARGUE WITH A LACK OF LIGHT SNOW OBSERVED CURRENTLY UPSTREAM NEAR THE WAVE OVER SOUTH CENTRAL CANADA. THINK THERE WILL BE SOME FLURRIES/SCT SNOW SHOWERS IN THE AFTERNOON AND WED NIGHT...MOST LIKELY CENTRAL AND EAST. UPDATE ISSUED AT 940 PM CST TUE FEB 23 2016 WE ADDED PATCHY FOG TO TONIGHT/S FORECAST FROM ROLLA SOUTH TOWARD THE JAMESTOWN AREA WHERE LIGHT LOW-LEVEL SOUTHEAST FLOW EXISTS ON THE WEST SIDE OF RETREATING HIGH PRESSURE...AND WHERE TEMPERATURE/ DEWPOINT SPREADS ARE LESS THAN 5 F AS OF 0330 UTC. HRRR SOLUTIONS ARE ALSO CONSISTENT IN SIGNALING SOME FOG IN THOSE AREAS. OTHER- WISE...ONLY MINOR CHANGES TO THE REST OF THE FORECAST...THOUGH WE DID INCREASE POPS SLIGHTLY AFTER 09 UTC IN SOUTHWEST ND USING A TIME-LAGGED...RAPID-REFRESH-BASED SUITE OF GUIDANCE. UPDATE ISSUED AT 550 PM CST TUE FEB 23 2016 NO SIGNIFICANT CHANGES WITH THIS UPDATE AS WEAK HIGH PRESSURE IS IN CONTROL OF THE WEATHER OVER WESTERN AND CENTRAL ND LATE THIS AFTERNOON. GUSTY WINDS IN SOUTHWESTERN ND HAVE BEEN ON A SLOW DOWNWARD TREND SINCE 22 UTC...AND SHOULD QUICKLY DIMINISH WITH SUNSET AS THE NEAR-GROUND LAYER COOLS...CAUSING AT LEAST A WEAK SURFACE-BASED INVERSION TO FORM PER MODEL FORECAST SOUNDINGS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 243 PM CST TUE FEB 23 2016 TUESDAY AFTERNOON BEGINS WITH A WEAK SHORTWAVE DEPARTING THE REGION WITH ANOTHER POISED TO MOVE IN LATE TONIGHT. CLOUDS HAVE GENERALLY CLEARED ACROSS WEST AND CENTRAL NORTH DAKOTA WITH A STRATO-CU FIELD IN PLACE ACROSS THE JAMES RIVER VALLEY. TO THE WEST GUST NORTHWEST WINDS OF 20 TO 30 MPH ARE MIXING WELL AND ALLOWING TEMPERATURES TO RISE INTO THE MID 40S ACROSS SOUTHWEST NORTH DAKOTA. TONIGHT CLOUDS WILL DECREASE ACROSS THE EAST AFTER SUNSET WITH INCREASING CLOUDS NORTH. THE CONSALL GUIDANCE GAVE A SLIGHT CHANCE FOR SNOW AFTER MIDNIGHT NORTHWEST AND NORTH CENTRAL. ON WEDNESDAY THE SHORTWAVE/FRONTAL SYSTEM WILL MOVE THROUGH. TEMPERATURES WILL BE COLD ENOUGH FOR MAINLY SNOW BUT ONCE AGAIN MOISTURE IS LIMITED AND SNOW AMOUNTS WILL BE CONFINED TO THE EAST WITH AMOUNTS LESS THAN AN INCH. OVERALL ABOUT 5 TO 15 DEGREES COOLER WEDNESDAY THAN TODAY AFTER THE COLD FRONT. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 243 PM CST TUE FEB 23 2016 FAST-MOVING UPPER LEVEL LOW MOVES ACROSS THE STATE DAYTIME WEDNESDAY. COLD ADVECTION CONTINUES WEDNESDAY NIGHT WITH LINGERING CLOUDS AND UPPER LEVEL LIFT FOR SMALL CHANCES OF LIGHT SNOW OVER EASTERN PORTIONS OF CENTRAL NORTH DAKOTA. A QUIET BUT COOL DAY THURSDAY AS THE COOL HIGH PRESSURE SYSTEM MOVES SOUTHEASTWARD ACROSS THE DAKOTAS. THURSDAY NIGHT ANOTHER FAST-MOVING UPPER LEVEL SHORTWAVE MOVES SOUTHEAST OUT OF THE CANADIAN FRONT RANGE AND CONTINUES SOUTHEAST ACROSS NORTH DAKOTA ON FRIDAY. A COLD FRONT ACCOMPANIES THE SYSTEM...BUT FOLLOWED QUICKLY BY A BUILDING RIDGE OVER THE ROCKIES. LOWS THURSDAY NIGHT IN THE UPPER TEENS AND 20S...BUT A BREEZY DAY FRIDAY WITH HIGHS REACHING THE LOWER 50S SOUTHWEST. A FAIRLY LARGE TEMPERATURE GRADIENT FROM NORTHEAST-TO-SOUTHWEST ACROSS THE STATE...WITH HIGHS ONLY IN THE MID TO UPPER 30S TURTLE MOUNTAINS AND NORTHERN JAMES VALLEY. SIMILAR TEMPERATURE GRADIENT FOR SATURDAY WITH VERY MILD CONDITIONS SOUTHWEST...BUT SEASONABLE IN THE NORTH CENTRAL AND JAMES VALLEY AS COOLER AIR BEGINS MOVING SOUTHWARD INTO NORTHEASTERN NORTH DAKOTA. A STRONGER PUSH OF COLD AIR PUSHES INTO THE STATE SATURDAY NIGHT AS AN UPPER LEVEL SHORTWAVE TROUGH EMERGES OUT OF THE ROCKIES AND MOVES EAST ACROSS THE NORTHERN PLAINS. THIS WILL BRING A CHANCE OF RAIN OR SNOW TO OUR AREA...AS WELL AS A COOL SPELL. LOOKING AT LOWS SATURDAY NIGHT FROM AROUND 5 ABOVE IN THE TURTLE MOUNTAINS TO UPPER 20S SOUTHWEST. WIDESPREAD LIGHT SNOW AMOUNTS ARE EXPECTED SATURDAY NIGHT THROUGH SUNDAY MORNING...MAINLY AN INCH OR LESS MOST AREAS. COOLER WEATHER SUNDAY INTO EARLY NEXT WEEK...AS THE LARGE HUDSON BAY LOW REMAINS ENTRENCHED OVER EASTERN NORTH AMERICA AND KEEPS ANY WESTERN NORTH AMERICA RIDGE FROM TAKING HOLD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1255 AM CST WED FEB 24 2016 CLOUD COVER WILL INCREASE TONIGHT AND ESPECIALLY ON WEDNESDAY AS A COLD FRONT APPROACHES AND THEN CROSSES THE AREA. LOW IFR CIGS AND FOG FORECAST EARLY THIS MORNING AROUND KJMS. MVFR CEILINGS ARE POSSIBLE OVER PARTS OF WESTERN AND CENTRAL ND ON WEDNESDAY BEHIND THE FRONT. WE ARE NOT PARTICULARLY CONFIDENT IN THE LOWER CEILINGS THOUGH GIVEN A LACK OF STRATUS OBSERVED UPSTREAM WITH THE FRONT. A FEW SNOW SHOWERS ARE ALSO POSSIBLE LATE TONIGHT WEST...THEN CENTRAL AND EAST WEDNESDAY AND WEDNESDAY NIGHT. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...NH SHORT TERM...WAA LONG TERM...JV AVIATION...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1153 PM CST TUE FEB 23 2016 .UPDATE... ISSUED AT 1151 PM CST TUE FEB 23 2016 ADDED PATCHY FOG TO THE NW FA OTHERWISE NO OTHER CHANGES. UPDATE ISSUED AT 926 PM CST TUE FEB 23 2016 CLOUDS CONTINUE TO SLOWLY THIN ACROSS THE REGION. COMBINED WITH FRESH SNOW AND LIGHT WINDS TEMPERATURES HAVE DROPPED OFF MORE THAN EXPECTED ALONG THE INTERNATIONAL BORDER AREA AND HAVE ACCORDINGLY LOWERED MINIMUM TEMPERATURES. UPDATE ISSUED AT 635 PM CST TUE FEB 23 2016 ADJUSTED CLOUD COVER SLIGHTLY OTHERWISE NO OTHER CHANGES. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 236 PM CST TUE FEB 23 2016 SFC LOW AND ASSOCIATED UPPER LEVEL VORT MOVING TOWARD WESTERN LAKE SUPERIOR NORTH OF DULUTH AT MID AFTN. SNOW HAS EXITED THE EASTERN FCST AREA AFTER A NARROW AREA OF 6 INCH SNOWFALL NR ROSEAU- WARROAD-LAKE OF THE WOODS REGION. SOME DRYING NOTED COMING SOUTH IN THE 925-850 MB LAYER AND DRYING IS FCST VIA HRRR TO MOVE INTO NW MN THIS EVENING. UNSURE HOW WIDESPREAD CLEARING WILL BE HOWEVER. CLOUD BAND LOCATED IN ERN ND NORTH INTO PARTS OF MANITOBA BTWN BRANDON AND WINNIPEG AND THIS CLOUD AREA IS MOVING SOUTH AND MAY HELP KEEP MUCH OF ERN ND FAIRLY CLOUDY INTO THE EVENING. SO AT FIRST SKY COVER TONIGHT MAY BE RATHER CHAOTIC. NOT A LOT OF COLD ADVECTION BUT ENOUGH COOLING TO GET LOWS DOWN INTO THE TEENS AND LOWER 20S. NEXT SHORT WAVE PRETTY WELL DEFINED MOVING INTO ECNTRL ALBERTA. NO PRECIP YET NOTED WITH SYSTEM VIA OBS OR CANADIAN RADAR. BUT THIS UPPER SYSTEM DOES STRENGTHEN AS IT DROPS SOUTH-SOUTHEAST INTO CNTRL ND 18Z-21Z PERIOD THEN INTO ERN SD WED EVENING. WITH CONVECTIVE SNOW BANDS WITH THE LAST TWO SYSTEMS IN AREA OF STEEP MID LEVEL LAPSE RATES (7 TO 7.5C/KM 700-500 MB)...CONCERN AGAIN WILL THIS OCCUR AGAIN. CERTAINLY POSSIBLE...AND DOES APPEAR MAIN RISK IS CNTRL ND INTO ERN SD BRUSHING SOUTHWESTERN FCST AREA. THIS IS THE AREA WITH THE BEST CHC OF 1 INCH OF SNOW (JMS-ABR-ATY REGION). DID INCREASE POPS WED 12-18Z IN WRN FCST AND THEN SPREAD EAST INTO RRV WED AFTN/NIGHT. FAR ERN FCST AREA ON THE EDGE WITH SYSTEM AS BEST AREAS FOR PRECIP APPEARS TO BE ON THE SOUTH AND WESTERN SIDE OF THE UPPER LOW. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 236 PM CST TUE FEB 23 2016 COOLER ON THURSDAY AS THE UPPER LOW DEPARTS AND SKIES BEGIN TO CLEAR. HIGH PRESSURE OVER THE AREA THU NIGHT. WARM ADVECTION BEGINS FRIDAY AS WINDS TURN SOUTH-SOUTHWEST. NUMERICAL GUIDANCE LIKELY A BIT UNDERDONE SO WENT A TAD HIGHER. BUT IF FULL SUN COULD BE EVEN HIGHER. FOR FRIDAY NIGHT THRU TUESDAY... MODELS ARE IN PRETTY GOOD AGREEMENT AT THE START OF THE PERIOD...WITH NORTHWEST FLOW ALOFT AND A FAIRLY WARM AIR MASS FRIDAY NIGHT AND SATURDAY AHEAD OF THE NEXT APPROACHING COLD FRONT. TEMPS WILL BE WELL ABOVE SEASONAL AVERAGES AND SATURDAY COULD EVEN BE WARMER THAN THE BLENDED SOLUTION HIGHS IF WE GET SOME SUN OVER OUR NO SNOW AREAS IN THE SOUTHWESTERN CWA. THE COLD FRONT WILL MOVE THROUGH SATURDAY NIGHT...BRINGING A CHANCE FOR SNOW AND COLDER TEMPS FOR SUNDAY. THE GFS IS MORE PHASED AND AMPLIFIED THAN THE OTHER DETERMINISTIC MODELS...BRINGING DOWN A STRONGER SURGE OF ARCTIC AIR. CONSIDERING THE OTHER DETERMINISTIC MODELS ARE MUCH WARMER AND MANY OF THE GFS ENSEMBLE MEMBERS ARE NOT AS AGGRESSIVE WITH THE COLDER AIR...WILL LEAN TOWARDS THE WARMER BLENDED SOLUTION AND KEEP READINGS ABOVE ZERO. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1151 PM CST TUE FEB 23 2016 ALTHOUGH ALL BUT BJI VFR MOST GUIDANCE BRINGS BACK IFR CIGS BACK INTO THE FA TOWARDS MORNING. WITH GOOD AGREEMENT BETWEEN GUIDANCE FOLLOWED SUIT WITH TAFS. MOST SNOW TOMORROW SHOULD REMAIN TO THE WEST OF THE FA. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...VOELKER SHORT TERM...RIDDLE LONG TERM...RIDDLE/JR AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
526 PM EST WED FEB 24 2016 .SYNOPSIS... DEEPENING LOW PRESSURE WILL MOVE NORTHEAST ACROSS NORTH CENTRAL OHIO THIS EVENING...AND CONTINUE INTO QUEBEC THURSDAY. A TROUGH WILL REMAIN IN THE WAKE OF THE LOW THROUGH THURSDAY. HIGH PRESSURE WILL BUILD ACROSS THE MISSISSIPPI AND OHIO VALLEYS FRIDAY...AND SHIFT OFF OF THE CAROLINA COAST SUNDAY. LOW PRESSURE WILL MOVE EAST ACROSS THE GREAT LAKES SUNDAY AND SUNDAY NIGHT...WITH A COLD FRONT CROSSING THE LOCAL AREA SUNDAY NIGHT. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... REMOVED MENTION OF TSRA FOR 630 UPDATE. TSRA TO SOUTH DIMINISHING AND WITH SUNSET SEE NO REASON TO CONTINUE MENTIONING TSRA. ORIGINAL DISCUSSION... LOW PRESSURE WAS CENTERED NEAR SPRINGFIELD OHIO AND ACCORDING TO PRESSURE FALLS...WILL CONTINUE NORTHEAST ACROSS ASHTABULA THIS EVENING AND THEN ACROSS LAKE ONTARIO TONIGHT. THE STEADIER STRATIFORM RAIN HAS PUSHED NORTH AND IN THE WARM SECTOR WE ARE SEEING CONVECTIVE BANDS ROTATING AROUND THE PARENT CIRCULATION. SCATTERED RAIN SHOWERS WILL CONTINUE THIS EVENING. ANOTHER NORTHERN STREAM BIT OF SHORTWAVE ENERGY WILL BE DIVING SOUTHEAST TONIGHT INTERACTING WITH THE UPPER LOW OVER THE OHIO VALLEY. COLDER AIR WILL WRAP INTO THIS SYSTEM...BUT IT WILL NOT BE EXCESSIVELY COLD. TEMPERATURES WILL SIGNIFICANTLY DROP ACROSS THE EAST WHERE THEY WERE ABLE TO WARM INTO THE 50S TODAY...BUT OVERALL ACROSS THE AREA WE ARE LOOKING AT TEMPS TO FALL INTO THE LOWER 30S BY THURSDAY MORNING/MIDDAY. AS THE LOW PASSES TO OUR NORTHEAST WINDS WILL COME AROUND TO THE NORTHWEST AND WEST- NORTHWEST FIRST NEAR THE TOLEDO/FINDLAY AREA THEN LATE TONIGHT ACROSS THE EAST. THE WIND SHIFT IS A DECENT PROXY TO THE POSITION OF THE RAIN/SNOW LINE. WRAP AROUND MOISTURE AND A TROUGH THAT WILL LINGER IN THE WAKE OF THE LOW WILL PROVIDE SUPPORT FOR PRECIPITATION. REALLY A MARGINAL SNOW EVENT BUT HAVE PUT UP A WINTER WEATHER ADVISORY FOR THE I-75 CORRIDOR. IT WILL BE BLUSTERY AND ACCUMULATIONS WILL LIKELY END UP NEAR 3 TO 4 INCHES THROUGH THURSDAY AFTERNOON. IT IS HIGHLY DEPENDENT UPON WHEN ACTUAL ACCUMULATING CAN START. BEGAN A WINTER WEATHER ADVISORY FOR NE OH LATER OVERNIGHT. BULK OF IMPACT WILL BE THURSDAY DURING THE DAY. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... WINTER WEATHER ADVISORY FOR NW OH CONTINUE THROUGH EARLY AFTERNOON THURSDAY. BY THEN SNOW WILL BECOME MORE SHOWERY AND WILL BE TAPERING. GUSTY WINDS WILL CONTINUE THROUGH THE DAY. AGAIN A MARGINAL SNOW EVENT FOR NE OH/NW PA AS THE SNOW WILL BE DRAWN OUT FROM THURSDAY MORNING THROUGH THURSDAY EVENING AND THURSDAY NIGHT. FOR THE MOST PART PEOPLE SHOULD END UP WITH 4 OR 5 INCHES. A FEW 6 INCH REPORTS POSSIBLE ACROSS NW PA. WE DO NOT GET A TRUE LAKE CONTRIBUTION UNTIL THURSDAY NIGHT. ELSEWHERE SNOW SHOWERS WILL CONTINUE FOR THURSDAY WITH ACCUMULATIONS OF 2 TO 3 INCHES IN THE END. SNOWBELT SNOW SHOWERS COME TO AN END LATE THURSDAY NIGHT/FRIDAY MORNING AS THE RIDGE BUILDS IN AND THE INVERSION DROPS. HIGH PRESSURE KEEPS ALL OTHERS QUIET AND DRY. TEMPERATURES WILL GO NO WHERE ON THURSDAY. AGAIN COLD AIR IS NOT ALL THAT IMPRESSIVE AND WE WILL END UP BEING SEASONABLE FOR FRIDAY. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE LONG TERM FORECAST BEGINS WITH A RATHER BENIGN SATURDAY AND FIRST HALF OF SUNDAY. HIGH PRESSURE AND RIDGING AT THE SURFACE WILL ALLOW FOR CALM WEATHER FOR THE WEEKEND. SOUTHERLY WINDS WILL ADVECT WARM MOIST AIR INTO THE REGION AND TEMPERATURES SHOULD BE SLIGHTLY ABOVE NORMAL ON SATURDAY AND THEN 10-15 DEGREES ABOVE NORMAL ON SUNDAY. CLOUD COVER WILL BE HIT AND MISS FOR THE MOST PART WITH AN INCREASE IN CLOUD COVER ON SUNDAY AFTERNOON AHEAD OF THE NEXT LOW PRESSURE SYSTEM. LATE ON SUNDAY INTO MONDAY... THE MODELS TEND TO BE IN FAIRLY GOOD AGREEMENT ON AN UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOW PRESSURE SYSTEM MOVING DOWN FROM CANADA. SINCE THE AIR AHEAD OF THIS SYSTEM WILL BE RATHER WARM...ANY PRECIPITATION WOULD START AS RAIN ON SUNDAY NIGHT INTO MONDAY. AS THIS LOW TRACKS EAST ON MONDAY COLD AIR WILL MOVE IN ON THE BACK SIDE OF THE LOW AND COOL TEMPERATURES DOWN BELOW FREEZING LATE MONDAY AFTERNOON AND THE PRECIPITATION TYPE WILL CHANGE OVER TO SNOW BEFORE THE SYSTEM MOVE OUT OF THE REGION. SINCE THIS LOW PRESSURE SYSTEM IS COMING FROM A COLD DRY CANADIAN CLIMATE...CAN CERTAINLY SEE THIS SYSTEM REMAINING RELATIVELY DRY AND SNOW CHANCES REMAINING RELATIVELY LIMITED BUT CONFIDENCE IN PRECIPITATION TIMING AND TYPE WILL INCREASE WITH TIME. FOR THE REST OF THE LONG TERM FORECAST BEYOND MONDAY NIGHT... THE GFS AND ECMWF MODEL SOLUTIONS BEGIN TO GREATLY DIFFER. THE GFS BRINGS IN AN ADDITIONAL LOW PRESSURE SYSTEM FROM CANADA THAT WOULD MISS THE AREA TO THE NORTH. THIS WOULD STREAM IN SOME WARM MOIST AIR FROM THE SOUTH AHEAD OF THE LOW AND A CHANCE FOR SOME RAIN. THIS SOLUTION WOULD USHER IN TEMPERATURES WELL ABOVE NORMAL FOR MID WEEK. CONVERSELY...THE ECMWF DRAWS IN A COOL CANADIAN HIGH THAT BRINGS COLD ARCTIC AIR INTO THE GREAT LAKES REGION. THIS SOLUTION WOULD INDICATE A DRIER AIR MASS BUT TEMPERATURES WELL BELOW AVERAGE. GIVEN THE DIFFERENT MODEL SOLUTIONS GENERALLY SPLIT THE DIFFERENCE ALTHOUGH BIASED THE GFS A BIT AS IT HAS HANDLED THE CURRENT SYSTEM BETTER AND THE WARMER SOLUTION SEEMS TO BE THE THEME AS OF LATE. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... WIDESPREAD IFR CONDITIONS OVER THE AREA AS THE SURFACE LOW TRACKS TOWARD THE AREA. GOES-14 ONE MINUTE RAPID SCAN SHOWING A LARGE AREA OF VFR CONDITION PUSHING OVER THE EASTERN LOCATIONS THIS AFTERNOON. HRRR MODEL SHOWS THESE VFR CONDITIONS IMPACTING YNG...ERI AND POSSIBLY CAK THIS AFTERNOON AND EVENING. IFR SHOULD REMAIN AT TOL AND FDY. MFD AND CLE WILL MOST LIKELY STAY IFR BUT COULD BRIEFLY LIFT TO MVFR OR VFR THIS AFTERNOON. RAIN WILL CHANGE TO SNOW OVERNIGHT. WESTERN SITES TOL AND FDY AROUND 00Z...04Z AT MFD AND CLE...AFT 06Z FOR CAK...YNG AND ERI. ALL SITES SHOULD HAVE SNOW BY 12Z THU. VISIBILITIES COULD DROP BELOW TWO MILES IN THE SNOW OVERNIGHT. MODERATE SNOW WITH VISIBILITIES OF 1/2 MILE OR LESS ARE NOT OUT OF THE QUESTION PERIODICALLY. LIGHT SNOW SHOULD REMAIN OVER THE TAF LOCATIONS THROUGH THE PERIOD. VISIBILITIES AND CEILINGS SHOULD IMPROVE IN THE WEST BY THURSDAY AFTERNOON. OUTLOOK...NON VFR WEDNESDAY NIGHT THROUGH THURSDAY NIGHT WITH PRECIPITATION TRANSITIONING TO SNOW EARLY THURSDAY. NON VFR WILL CONTINUE IN SCATTERED SNOW SHOWERS ACROSS NW PA ON FRIDAY. && .MARINE... A STRONG LOW PRESSURE SYSTEM WILL MOVE ACROSS LAKE ERIE OVERNIGHT. THE CENTER OF THE STORM SYSTEM SHOULD PASS DIRECTLY OVER THE CENTER SECTIONS OF THE LAKE. THIS WILL CREATE VARIABLE WIND DIRECTIONS OVERNIGHT AND WIND SPEEDS WILL DECREASE. I WILL ALLOW THE GALE WARNING TO EXPIRE. STRONG COLD AIR ADVECTION WILL FOLLOW THE FRONT ON THURSDAY. WINDS WILL SHIFT TO THE NORTHWEST AND INCREASE DURING THE AFTERNOON. MODELS CURRENTLY HAVE WINDS AROUND 30 KNOTS WITH SOME GUSTS TO 40 KNOTS. IT IS A MARGINAL GALE FOR THURSDAY. I AM GOING TO HOLD OFF ON THE GALE WARNING FOR NOW BUT IT WILL NEED TO BE MONITORED. NORTHWEST WINDS WILL DECREASE THURSDAY NIGHT INTO FRIDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...WINTER WEATHER ADVISORY FROM 3 AM TO 7 PM EST THURSDAY FOR OHZ011>014-089. WINTER WEATHER ADVISORY UNTIL 1 PM EST THURSDAY FOR OHZ003-006- 017. PA...WINTER WEATHER ADVISORY FROM 6 AM THURSDAY TO 6 AM EST FRIDAY FOR PAZ001>003. MARINE...NONE. && $$ SYNOPSIS...OUDEMAN NEAR TERM...DJB/OUDEMAN SHORT TERM...OUDEMAN LONG TERM...SEFCOVIC AVIATION...GARNET MARINE...GARNET
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
409 PM EST WED FEB 24 2016 .SYNOPSIS... DEEPENING LOW PRESSURE WILL MOVE NORTHEAST ACROSS NORTH CENTRAL OHIO THIS EVENING...AND CONTINUE INTO QUEBEC THURSDAY. A TROUGH WILL REMAIN IN THE WAKE OF THE LOW THROUGH THURSDAY. HIGH PRESSURE WILL BUILD ACROSS THE MISSISSIPPI AND OHIO VALLEYS FRIDAY...AND SHIFT OFF OF THE CAROLINA COAST SUNDAY. LOW PRESSURE WILL MOVE EAST ACROSS THE GREAT LAKES SUNDAY AND SUNDAY NIGHT...WITH A COLD FRONT CROSSING THE LOCAL AREA SUNDAY NIGHT. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... LOW PRESSURE WAS CENTERED NEAR SPRINGFIELD OHIO AND ACCORDING TO PRESSURE FALLS...WILL CONTINUE NORTHEAST ACROSS ASHTABULA THIS EVENING AND THEN ACROSS LAKE ONTARIO TONIGHT. THE STEADIER STRATIFORM RAIN HAS PUSHED NORTH AND IN THE WARM SECTOR WE ARE SEEING CONVECTIVE BANDS ROTATING AROUND THE PARENT CIRCULATION. SCATTERED RAIN SHOWERS WILL CONTINUE THIS EVENING. ANOTHER NORTHERN STREAM BIT OF SHORTWAVE ENERGY WILL BE DIVING SOUTHEAST TONIGHT INTERACTING WITH THE UPPER LOW OVER THE OHIO VALLEY. COLDER AIR WILL WRAP INTO THIS SYSTEM...BUT IT WILL NOT BE EXCESSIVELY COLD. TEMPERATURES WILL SIGNIFICANTLY DROP ACROSS THE EAST WHERE THEY WERE ABLE TO WARM INTO THE 50S TODAY...BUT OVERALL ACROSS THE AREA WE ARE LOOKING AT TEMPS TO FALL INTO THE LOWER 30S BY THURSDAY MORNING/MIDDAY. AS THE LOW PASSES TO OUR NORTHEAST WINDS WILL COME AROUND TO THE NORTHWEST AND WEST- NORTHWEST FIRST NEAR THE TOLEDO/FINDLAY AREA THEN LATE TONIGHT ACROSS THE EAST. THE WIND SHIFT IS A DECENT PROXY TO THE POSITION OF THE RAIN/SNOW LINE. WRAP AROUND MOISTURE AND A TROUGH THAT WILL LINGER IN THE WAKE OF THE LOW WILL PROVIDE SUPPORT FOR PRECIPITATION. REALLY A MARGINAL SNOW EVENT BUT HAVE PUT UP A WINTER WEATHER ADVISORY FOR THE I-75 CORRIDOR. IT WILL BE BLUSTERY AND ACCUMULATIONS WILL LIKELY END UP NEAR 3 TO 4 INCHES THROUGH THURSDAY AFTERNOON. IT IS HIGHLY DEPENDENT UPON WHEN ACTUAL ACCUMULATING CAN START. BEGAN A WINTER WEATHER ADVISORY FOR NE OH LATER OVERNIGHT. BULK OF IMPACT WILL BE THURSDAY DURING THE DAY. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... WINTER WEATHER ADVISORY FOR NW OH CONTINUE THROUGH EARLY AFTERNOON THURSDAY. BY THEN SNOW WILL BECOME MORE SHOWERY AND WILL BE TAPERING. GUSTY WINDS WILL CONTINUE THROUGH THE DAY. AGAIN A MARGINAL SNOW EVENT FOR NE OH/NW PA AS THE SNOW WILL BE DRAWN OUT FROM THURSDAY MORNING THROUGH THURSDAY EVENING AND THURSDAY NIGHT. FOR THE MOST PART PEOPLE SHOULD END UP WITH 4 OR 5 INCHES. A FEW 6 INCH REPORTS POSSIBLE ACROSS NW PA. WE DO NOT GET A TRUE LAKE CONTRIBUTION UNTIL THURSDAY NIGHT. ELSEWHERE SNOW SHOWERS WILL CONTINUE FOR THURSDAY WITH ACCUMULATIONS OF 2 TO 3 INCHES IN THE END. SNOWBELT SNOW SHOWERS COME TO AN END LATE THURSDAY NIGHT/FRIDAY MORNING AS THE RIDGE BUILDS IN AND THE INVERSION DROPS. HIGH PRESSURE KEEPS ALL OTHERS QUIET AND DRY. TEMPERATURES WILL GO NO WHERE ON THURSDAY. AGAIN COLD AIR IS NOT ALL THAT IMPRESSIVE AND WE WILL END UP BEING SEASONABLE FOR FRIDAY. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE LONG TERM FORECAST BEGINS WITH A RATHER BENIGN SATURDAY AND FIRST HALF OF SUNDAY. HIGH PRESSURE AND RIDGING AT THE SURFACE WILL ALLOW FOR CALM WEATHER FOR THE WEEKEND. SOUTHERLY WINDS WILL ADVECT WARM MOIST AIR INTO THE REGION AND TEMPERATURES SHOULD BE SLIGHTLY ABOVE NORMAL ON SATURDAY AND THEN 10-15 DEGREES ABOVE NORMAL ON SUNDAY. CLOUD COVER WILL BE HIT AND MISS FOR THE MOST PART WITH AN INCREASE IN CLOUD COVER ON SUNDAY AFTERNOON AHEAD OF THE NEXT LOW PRESSURE SYSTEM. LATE ON SUNDAY INTO MONDAY... THE MODELS TEND TO BE IN FAIRLY GOOD AGREEMENT ON AN UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOW PRESSURE SYSTEM MOVING DOWN FROM CANADA. SINCE THE AIR AHEAD OF THIS SYSTEM WILL BE RATHER WARM...ANY PRECIPITATION WOULD START AS RAIN ON SUNDAY NIGHT INTO MONDAY. AS THIS LOW TRACKS EAST ON MONDAY COLD AIR WILL MOVE IN ON THE BACK SIDE OF THE LOW AND COOL TEMPERATURES DOWN BELOW FREEZING LATE MONDAY AFTERNOON AND THE PRECIPITATION TYPE WILL CHANGE OVER TO SNOW BEFORE THE SYSTEM MOVE OUT OF THE REGION. SINCE THIS LOW PRESSURE SYSTEM IS COMING FROM A COLD DRY CANADIAN CLIMATE...CAN CERTAINLY SEE THIS SYSTEM REMAINING RELATIVELY DRY AND SNOW CHANCES REMAINING RELATIVELY LIMITED BUT CONFIDENCE IN PRECIPITATION TIMING AND TYPE WILL INCREASE WITH TIME. FOR THE REST OF THE LONG TERM FORECAST BEYOND MONDAY NIGHT... THE GFS AND ECMWF MODEL SOLUTIONS BEGIN TO GREATLY DIFFER. THE GFS BRINGS IN AN ADDITIONAL LOW PRESSURE SYSTEM FROM CANADA THAT WOULD MISS THE AREA TO THE NORTH. THIS WOULD STREAM IN SOME WARM MOIST AIR FROM THE SOUTH AHEAD OF THE LOW AND A CHANCE FOR SOME RAIN. THIS SOLUTION WOULD USHER IN TEMPERATURES WELL ABOVE NORMAL FOR MID WEEK. CONVERSELY...THE ECMWF DRAWS IN A COOL CANADIAN HIGH THAT BRINGS COLD ARCTIC AIR INTO THE GREAT LAKES REGION. THIS SOLUTION WOULD INDICATE A DRIER AIR MASS BUT TEMPERATURES WELL BELOW AVERAGE. GIVEN THE DIFFERENT MODEL SOLUTIONS GENERALLY SPLIT THE DIFFERENCE ALTHOUGH BIASED THE GFS A BIT AS IT HAS HANDLED THE CURRENT SYSTEM BETTER AND THE WARMER SOLUTION SEEMS TO BE THE THEME AS OF LATE. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... WIDESPREAD IFR CONDITIONS OVER THE AREA AS THE SURFACE LOW TRACKS TOWARD THE AREA. GOES-14 ONE MINUTE RAPID SCAN SHOWING A LARGE AREA OF VFR CONDITION PUSHING OVER THE EASTERN LOCATIONS THIS AFTERNOON. HRRR MODEL SHOWS THESE VFR CONDITIONS IMPACTING YNG...ERI AND POSSIBLY CAK THIS AFTERNOON AND EVENING. IFR SHOULD REMAIN AT TOL AND FDY. MFD AND CLE WILL MOST LIKELY STAY IFR BUT COULD BRIEFLY LIFT TO MVFR OR VFR THIS AFTERNOON. RAIN WILL CHANGE TO SNOW OVERNIGHT. WESTERN SITES TOL AND FDY AROUND 00Z...04Z AT MFD AND CLE...AFT 06Z FOR CAK...YNG AND ERI. ALL SITES SHOULD HAVE SNOW BY 12Z THU. VISIBILITIES COULD DROP BELOW TWO MILES IN THE SNOW OVERNIGHT. MODERATE SNOW WITH VISIBILITIES OF 1/2 MILE OR LESS ARE NOT OUT OF THE QUESTION PERIODICALLY. LIGHT SNOW SHOULD REMAIN OVER THE TAF LOCATIONS THROUGH THE PERIOD. VISIBILITIES AND CEILINGS SHOULD IMPROVE IN THE WEST BY THURSDAY AFTERNOON. OUTLOOK...NON VFR WEDNESDAY NIGHT THROUGH THURSDAY NIGHT WITH PRECIPITATION TRANSITIONING TO SNOW EARLY THURSDAY. NON VFR WILL CONTINUE IN SCATTERED SNOW SHOWERS ACROSS NW PA ON FRIDAY. && .MARINE... A STRONG LOW PRESSURE SYSTEM WILL MOVE ACROSS LAKE ERIE OVERNIGHT. THE CENTER OF THE STORM SYSTEM SHOULD PASS DIRECTLY OVER THE CENTER SECTIONS OF THE LAKE. THIS WILL CREATE VARIABLE WIND DIRECTIONS OVERNIGHT AND WIND SPEEDS WILL DECREASE. I WILL ALLOW THE GALE WARNING TO EXPIRE. STRONG COLD AIR ADVECTION WILL FOLLOW THE FRONT ON THURSDAY. WINDS WILL SHIFT TO THE NORTHWEST AND INCREASE DURING THE AFTERNOON. MODELS CURRENTLY HAVE WINDS AROUND 30 KNOTS WITH SOME GUSTS TO 40 KNOTS. IT IS A MARGINAL GALE FOR THURSDAY. I AM GOING TO HOLD OFF ON THE GALE WARNING FOR NOW BUT IT WILL NEED TO BE MONITORED. NORTHWEST WINDS WILL DECREASE THURSDAY NIGHT INTO FRIDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...WINTER WEATHER ADVISORY FROM 3 AM TO 7 PM EST THURSDAY FOR OHZ011>014-089. WINTER WEATHER ADVISORY UNTIL 1 PM EST THURSDAY FOR OHZ003-006- 017. PA...WINTER WEATHER ADVISORY FROM 6 AM THURSDAY TO 6 AM EST FRIDAY FOR PAZ001>003. MARINE...NONE. && $$ SYNOPSIS...OUDEMAN NEAR TERM...OUDEMAN SHORT TERM...OUDEMAN LONG TERM...SEFCOVIC AVIATION...GARNET MARINE...GARNET
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1254 PM EST WED FEB 24 2016 .SYNOPSIS... A STRONG LOW PRESSURE SYSTEM WILL CROSS NORTHEAST THROUGH THE OHIO VALLEY TODAY. UPPER LEVEL LOW PRESSURE WILL COMBINE WITH THE SURFACE LOW THIS EVENING WHEN THEY REACH NORTHERN OHIO...AND RAIN WILL RAPIDLY CHANGE OVER TO SNOW FROM WEST TO EAST OVERNIGHT AS THE COLD AIR GETS PULLED IN ON WESTERLY WIND. NORTHWEST FLOW WITH LAKE ENHANCED SNOW SHOWERS WILL CONTINUE AS A RIDGE OF HIGH PRESSURE BUILDS IN THE MIDWEST ON FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WIDESPREAD RAIN SHIELD HAS PIVOTED UP INTO NORTHERN OHIO WITH PRECIPITATION ACROSS MUCH OF OUR AREA NOW LIGHTER AND SOMEWHAT MORE SCATTERED. PCPN AMOUNTS HAVE GENERALLY BEEN AN INCH OR SO...WITH THE HIGHEST AMOUNTS OF AN INCH TO AN INCH AND A QUARTER MAINLY ACROSS WESTERN PORTIONS OF OUR AREA. WE HAVE HAD A FEW SPOTTY REPORTS OF ICING ACROSS OUR FAR NORTHWEST WHERE TEMPERATURES ARE CURRENTLY IN THE LOW TO MID 30S. ROAD TEMPERATURES ARE STILL WARM SO DO NOT EXPECT MUCH OF A TRAVEL ISSUE WITH THIS...BUT SOME LIGHT ICING ON EXPOSED SURFACES WILL BE POSSIBLE THROUGH LATE MORNING UNTIL TEMPERATURES BUMP UP INTO THE UPPER 30S. HAVE ISSUED AN SPS TO ADDRESS THIS. THE SURFACE LOW WILL LIFT NORTHEAST ALONG THE I-71 CORRIDOR THROUGH THIS AFTERNOON. ALONG AND SOUTHEAST OF THIS WHERE WE WILL GET INTO A BIT OF A WARM SECTOR...THE RAP CONTINUES TO SHOW SOME WEAK INSTABILITIES OF GENERALLY 500 J/KG OR LESS DEVELOPING THROUGH LATE MORNING INTO MID AFTERNOON. THIS COULD LEAD TO SOME ISOLATED THUNDERSTORM DEVELOPMENT AS WE HEAD INTO THE AFTERNOON. THE BETTER INSTABILITY WILL NOT BE COMPLETELY SYNCED UP WITH THE BETTER SHEAR PROFILES WHICH WILL BE SHIFTING OFF TO THE NORTHEAST THROUGH EARLY AFTERNOON. HOWEVER..ALONG THE INTERFACE OF THE INCREASING INSTABILITY AND DECREASING SHEAR...IT WILL BE TOUGH TO RULE OUT A FEW STRONG TO SEVERE STORMS WITH EVEN AN ISOLATED TORNADO POSSIBLE. THE BEST CHANCE FOR THIS WOULD LIKELY BE ACROSS OUR FAR SOUTHEAST...WHERE THE BEST INSTABILITY SHOULD EXIST. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/... AS THE LOW CROSSES THROUGH NORTHERN OHIO THIS EVENING COLDER AIR WILL BE USHERED IN ON WESTERLY WINDS AND RAIN WILL CHANGE OVER TO SNOW. ACCUMULATIONS WILL BE LIMITED GIVEN THE WARM AND WET GROUND BUT THE POTENTIAL FOR 1-3 INCHES OF ACCUMULATION IS EXPECTED GIVEN THE TEMPERATURE PROFILE AND EXPECTED QPF...WITH THE HIGHER AMOUNTS NOTED NORTH OF METROPOLITAN DAYTON. AS THE COLD AIR PUSHES IN....SOME WIND GUSTS TO 40 MPH WILL BE POSSIBLE TONIGHT INTO THURSDAY. COLD ADVECTION WILL LIKELY KEEP SOME FORM OF SNOW SHOWERS OVER THE REGION THURSDAY AND THEN TAPER OFF OVERNIGHT. NORTHWEST FLOW WILL TAP MOISTURE FROM LAKE MICHIGAN AND KEEP THE THREAT OF SNOW SHOWERS IN THE FORECAST FOR FRIDAY AFTERNOON. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... THE EXTENDED FORECAST PERIOD WILL BEGIN WITH A SHARP TROUGH DEVELOPING IN THE FAR WESTERN STATES...WITH BROAD RIDGING ACROSS THE EASTERN TWO THIRDS OF THE COUNTRY. SURFACE HIGH PRESSURE WILL BE CENTERED OVER THE LOWER MISSISSIPPI VALLEY...MOVING EAST-SOUTHEAST AND GRAZING PAST THE OHIO VALLEY AND ILN FORECAST AREA. WHILE THERE IS A SLIGHT CHANCE THAT SOME FLURRIES OR LIGHT SNOW SHOWERS COULD BE CONTINUING WITHIN THE MIXED BOUNDARY LAYER ON FRIDAY MORNING...A DRY FORECAST WILL BE MAINTAINED FOR NOW. A THICK STRATOCUMULUS DECK LOOKS PRETTY LIKELY TO EXIST...AND THIS MAY NOT CLEAR UNTIL THE EVENING...WHEN WARM ADVECTION ALOFT BEGINS. A WEAK SHORTWAVE WILL MOVE THROUGH THE REGION FRIDAY NIGHT AND SATURDAY...BUT WITH VERY LITTLE MOISTURE...AND DRY CONDITIONS ARE EXPECTED. THE WARM ADVECTION WILL BEGIN TO INCREASE BY SATURDAY...WITH RIDGING BUILDING IN FOR THE SOUTHEASTERN STATES...AND A SHIFT TO SOUTHWESTERLY FLOW IN THE LOWER LEVELS OF THE ATMOSPHERE. IN FACT...SOME GUSTY CONDITIONS COULD BE POSSIBLE ON BOTH SATURDAY AND SUNDAY...WITH A TIGHTENING PRESSURE GRADIENT ACROSS THE MIDDLE MISSISSIPPI VALLEY AND INTO THE SOUTHERN GREAT LAKES REGION. AS RIDGING MOVES TO THE EAST...THE NEXT SHORTWAVE FORECAST TO AFFECT THE OHIO VALLEY IS EXPECTED TO MOVE THROUGH ON SUNDAY NIGHT. OVERALL TIMING AND PLACEMENT ALIGNMENT ON THE 06Z/12Z GFS AND 00Z/12Z ECMWF ARE GOOD...BUT UNSURPRISINGLY...DETAILS ON THE SPEED OF THE WAVE AND THE STRENGTH OF A DEVELOPING SURFACE LOW ARE IN MUCH POORER AGREEMENT. AFTER A COUPLE DAYS OF WARM ADVECTION...WHATEVER PRECIPITATION OCCURS SHOULD START AS RAIN...AND MAY STAY THAT WAY IN THE SOUTHERN AND SOUTHEASTERN SECTIONS OF THE FORECAST AREA. A MIX WITH SNOW WILL BE MORE LIKELY FURTHER TO THE NORTH. FOR MONDAY AND BEYOND...MODEL DIFFERENCES BECOME TOO LARGE TO ACCURATELY PREDICT A SPECIFIC DETERMINISTIC RESULT. THERE IS SIGNIFICANT DISAGREEMENT ON HOW FAR SOUTH A COLD FRONT IS ABLE TO TRAVEL ON MONDAY AND MONDAY NIGHT...AND THE PROGRESSION OF UPSTREAM TROUGHING BEYOND THAT POINT IS IN SIGNIFICANT DISAGREEMENT. AFTER MONDAY...500MB GFSE PERTURBATIONS BECOME COMPLETELY MISALIGNED AND OUT OF PHASE. THUS...SPECIFICS IN THE FORECAST BEYOND MONDAY ARE VERY LOW IN CONFIDENCE. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... SURFACE LOW LOOKS TO BE JUST WEST OF KCVG WITH A WARM FRONT EXTENDING EAST ALONG THE OHIO RIVER. A LINE OF SHOWERS AND THUNDERSTORMS HAS DEVELOPED ALONG THE WARM FRONT. THE SURFACE LOW WILL RIDE UP ALONG I-71 THROUGH MID TO LATE AFTERNOON. AS IT DOES...EXPECT THE LINE OF SHOWERS AND THUNDERSTORMS TO WORK UP TOWARD CENTRAL OHIO OVER THE NEXT FEW HOURS. SOME BRIEF HEAVY RAIN WILL BE POSSIBLE WITH THESE STORMS WITH VSBYS DROPPING DOWN TO IFR. AS THE WARM FRONT MOVES THROUGH...WINDS WILL BECOME SOUTHERLY AND INCREASE WITH SOME GUSTS AS HIGH AS 30 KNOTS POSSIBLE THROUGH MID TO LATE AFTERNOON. CIGS WILL TREND TOWARD VFR...BUT OCCASIONAL SHOWERS AND MVFR CIGS WILL ALSO PERSIST THROUGH THE AFTERNOON HOURS. GOOD CAA WILL DEVELOP ON THE BACKSIDE OF THE LOW AS IT MOVES OFF TO THE NORTHEAST. THIS WILL ALLOW FOR SHOWERS TO CHANGE OVER TO SNOW THIS EVENING FROM WEST TO EAST. IN GOOD CAA...GUSTY WEST WINDS WILL CONTINUE THROUGH THE REMAINDER OF THE TAF PERIOD. EXPECT IFR CIGS AND IFR TO MVFR VSBYS WITH OCCASIONAL SNOW/SNOW SHOWERS TO PREVAIL ON INTO THURSDAY. OUTLOOK...MVFR CEILINGS MAY CONTINUE INTO FRIDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...FLOOD WATCH THROUGH LATE TONIGHT FOR OHZ070>074-077>082-088. KY...FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ089>100. IN...FLOOD WATCH THROUGH LATE TONIGHT FOR INZ066-073>075-080. && $$ SYNOPSIS...FRANKS NEAR TERM...JGL SHORT TERM...FRANKS LONG TERM...HATZOS AVIATION...JGL
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1239 PM EST WED FEB 24 2016 .SYNOPSIS... DEEPENING LOW PRESSURE WILL MOVE NORTHEAST THROUGH OHIO TODAY. THE LOW WILL MOVE NORTHEAST INTO QUEBEC TONIGHT AND THURSDAY MORNING. HIGH PRESSURE WILL BUILD SOUTHEAST TO THE GULF COAST STATES BY FRIDAY AND EXTEND A RIDGE NORTH OVER THE FORECAST AREA. ANOTHER AREA OF LOW PRESSURE WILL MOVE EAST THROUGH THE GREAT LAKES SUNDAY INTO MONDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... NO BIG CHANGES WITH THIS MIDDAY UPDATE. STILL EVALUATING SNOW POTENTIAL TONIGHT INTO THURSDAY AND A NEW ADVISORY IS NOT OUT OF THE QUESTION FOR AT LEAST NW OH. NE OH/NW PA ALSO A CONCERN BUT MORE FOR THURSDAY. MONITORING RAINFALL AMOUNTS. AS OF 10 AM HAVE RECEIVED 1.01 INCHES AT MANSFIELD. CAK AND MNN AT 0.98 INCHES. FDY AT 0.70. SHORT TERM CONCERN LIES WITH CONVECTIVE NATURE OF THE CLOUDS DEVELOPING TO OUR SOUTH AND PUSHING NORTHWARD TOWARD THE CENTRAL HIGHLANDS AND THE MAHONING VALLEY. CONCERN WITH SATURATED GROUNDS AND THE POTENTIAL FOR CONVECTIVE RAINFALL ON TOP OF THAT. HAVE CONTINUED THE MENTION OF THUNDER IN THE FORECAST. WILL WATCH FLOOD THREAT. TRACK OF SYSTEM BASED ON THE PRESSURE FALLS IS HEADED TOWARD CENTRAL OHIO AND EVENTUALLY NORTH-CENTRAL OHIO THIS EVENING. THIS IS SLIGHTLY FASTER THAN YESTERDAYS MODEL RUNS. HAVE MADE MINOR ADJUSTMENTS TO THE FORECAST FOR TODAY/TONIGHT. DELAYED BIG RISE IN TEMPS ACROSS THE SOUTHEAST BY JUST A FEW HOURS. NICE GRADIENT IN TEMPS EXPECTED...WITH MID/UPPER 30S ACROSS THE WEST AND NORTHWEST AND MID 50S ACROSS THE FAR SOUTHEAST. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... DEEP UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE GRADUALLY EAST OVER THE FORECAST AREA TONIGHT. THIS WILL FORCE DEEP SURFACE LOW PRESSURE TO MOVE NORTHEAST AND OUT OF THE AREA AS WELL. AS SURFACE LOW PRESSURE MOVES OVER THE FORECAST AREA...EXPECTING RAIN TO PERSIST INTO TONIGHT AND THEN WRAP AROUND COLD AIR ADVECTION WILL TAKE PLACE. THIS SHOULD CAUSE A TRANSITION OVER TO SNOW FROM THE RAIN. SNOW WILL FALL ACROSS THE AREA TONIGHT INTO THURSDAY AND WILL GRADUALLY PULL OUT FROM WEST TO EAST. THE MEAN FLOW SHOULD SUPPORT SOME LAKE EFFECT SNOW ACTIVITY THURSDAY NIGHT INTO FRIDAY AND SOME LINGERING SNOW ACTIVITY IN THE NORTHEAST SATURDAY. OTHERWISE...HIGH PRESSURE RIDGE WILL BUILD INTO THE FORECAST AREA FROM THE WEST AND BRING A RETURN BACK TO FAIR WEATHER FOR MOST OF THE FORECAST AREA. TEMPERATURES WILL BE TRENDING DOWNWARD AS THE COLD AIR ADVECTION BEGINS LATER TONIGHT AND CONTINUING INTO SATURDAY. && .LONG TERM /SUNDAY THROUGH TUESDAY/... NOT A LOT OF CONFIDENCE IN THE EXTENDED FORECAST. WITH THE FAST MOVEMENT OF THE SYSTEMS...ANY TIMING DIFFERENCES CAN MAKE FOR SIGNIFICANT TEMPERATURE AND POP ERRORS. THE MODELS WANT TO BRING THE WARM AIR BACK ON SUNDAY AHEAD OF THE NEXT FRONT. SHOWERS WILL LIKELY HOLD OFF UNTIL FRONTAL PASSAGE SUNDAY NIGHT BUT GUIDANCE GIVES POPS FROM ABOUT 10 PERCENT IN THE SOUTH TO NEAR 25 PERCENT AROUND TOLEDO AND CANNOT REALLY ARGUE AT THIS TIME. HIGHS WILL REBOUND TO NEAR 50 OR PERHAPS A LITTLE BETTER. THE GUSTY PACIFIC FRONT SHOULD BE EAST OF THE AREA BY MONDAY. THE MODELS SHOW A SECONDARY COLD FRONT BY TUESDAY BUT THE MODELS BEGIN TO DIVERGE. THE GFS IS FASTER WITH THE FRONTAL PASSAGE. THE CMC AND ECMWF ARE SLOWER AND THE ECMWF IS WETTER. THE CURRENT FORECAST HAS A CHANCE OF RAIN AND SNOW SHOWERS AND WILL STAND PAT FOR NOW GIVEN THE WIDE RANGE OF SOLUTIONS. TEMPERATURES WILL DEPEND ON THE TIMING OF THE FRONT. FORECAST TEMPS NEAR NORMAL AS A COMPROMISE FOR THE TIME BEING. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... WIDESPREAD IFR CONDITIONS OVER THE AREA AS THE SURFACE LOW TRACKS TOWARD THE AREA. GOES-14 ONE MINUTE RAPID SCAN SHOWING A LARGE AREA OF VFR CONDITION PUSHING OVER THE EASTERN LOCATIONS THIS AFTERNOON. HRRR MODEL SHOWS THESE VFR CONDITIONS IMPACTING YNG...ERI AND POSSIBLY CAK THIS AFTERNOON AND EVENING. IFR SHOULD REMAIN AT TOL AND FDY. MFD AND CLE WILL MOST LIKELY STAY IFR BUT COULD BRIEFLY LIFT TO MVFR OR VFR THIS AFTERNOON. RAIN WILL CHANGE TO SNOW OVERNIGHT. WESTERN SITES TOL AND FDY AROUND 00Z...04Z AT MFD AND CLE...AFT 06Z FOR CAK...YNG AND ERI. ALL SITES SHOULD HAVE SNOW BY 12Z THU. VISIBILITIES COULD DROP BELOW TWO MILES IN THE SNOW OVERNIGHT. MODERATE SNOW WITH VISIBILITIES OF 1/2 MILE OR LESS ARE NOT OUT OF THE QUESTION PERIODICALLY. LIGHT SNOW SHOULD REMAIN OVER THE TAF LOCATIONS THROUGH THE PERIOD. VISIBILITIES AND CEILINGS SHOULD IMPROVE IN THE WEST BY THURSDAY AFTERNOON. OUTLOOK...NON VFR WEDNESDAY NIGHT THROUGH THURSDAY NIGHT WITH PRECIPITATION TRANSITIONING TO SNOW EARLY THURSDAY. NON VFR WILL CONTINUE IN SCATTERED SNOW SHOWERS ACROSS NW PA ON FRIDAY. && .MARINE... A STRONG LOW PRESSURE SYSTEM WILL TRACK FROM THE LOWER OHIO VALLEY THIS MORNING ACROSS LAKE ERIE THIS EVENING AND THEN ACROSS QUEBEC ON THURSDAY. THE EXACT TRACK OVER LAKE ERIE IS STILL A LITTLE UNCERTAIN...IT WILL CROSS THE LAKE SOMEWHERE OVER THE WESTERN OR CENTRAL BASIN. NORTHEAST WINDS WILL INCREASE RAPIDLY AHEAD OF THE LOW THIS MORNING AND GALE FORCE WINDS ARE LIKELY FOR A SHORT TIME ON THE CENTRAL AND WESTERN BASIN FROM MID MORNING THROUGH MID AFTERNOON. WINDS WILL DIMINISH FOR A WHILE TONIGHT WITH THE PASSAGE OF THE LOW...THEN PICK BACK UP FROM THE WEST NORTHWEST BY THURSDAY MORNING ON THE BACK SIDE OF THE LOW. GALE FORCE WINDS ARE POSSIBLE AGAIN ON THURSDAY BUT THE MAJORITY OF THE LAKE WILL PROBABLY STAY AROUND 30 KNOTS. WILL EMPHASIZE THE FIRST GALE WARNING TODAY AND CONTINUE TO EXAMINE THE POSSIBILITY OF A GALE AGAIN ON THURSDAY. HIGH PRESSURE WILL BUILD IN FROM THE WEST BY LATE FRIDAY. WINDS WILL BACK TO THE SOUTHWEST BY SATURDAY AND INCREASE ON SUNDAY AHEAD OF A COLD FRONT. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...GALE WARNING UNTIL 4 PM EST THIS AFTERNOON FOR LEZ142>148- 162>168. && $$ SYNOPSIS...LOMBARDY NEAR TERM...LOMBARDY/OUDEMAN SHORT TERM...LOMBARDY LONG TERM...KOSARIK AVIATION...GARNET MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
935 AM EST WED FEB 24 2016 .SYNOPSIS... A STRONG LOW PRESSURE SYSTEM WILL CROSS NORTHEAST THROUGH THE OHIO VALLEY TODAY. UPPER LEVEL LOW PRESSURE WILL COMBINE WITH THE SURFACE LOW THIS EVENING WHEN THEY REACH NORTHERN OHIO...AND RAIN WILL RAPIDLY CHANGE OVER TO SNOW FROM WEST TO EAST OVERNIGHT AS THE COLD AIR GETS PULLED IN ON WESTERLY WIND. NORTHWEST FLOW WITH LAKE ENHANCED SNOW SHOWERS WILL CONTINUE AS A RIDGE OF HIGH PRESSURE BUILDS IN THE MIDWEST ON FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WIDESPREAD RAIN SHIELD HAS PIVOTED UP INTO NORTHERN OHIO WITH PRECIPITATION ACROSS MUCH OF OUR AREA NOW LIGHTER AND SOMEWHAT MORE SCATTERED. PCPN AMOUNTS HAVE GENERALLY BEEN AN INCH OR SO...WITH THE HIGHEST AMOUNTS OF AN INCH TO AN INCH AND A QUARTER MAINLY ACROSS WESTERN PORTIONS OF OUR AREA. WE HAVE HAD A FEW SPOTTY REPORTS OF ICING ACROSS OUR FAR NORTHWEST WHERE TEMPERATURES ARE CURRENTLY IN THE LOW TO MID 30S. ROAD TEMPERATURES ARE STILL WARM SO DO NOT EXPECT MUCH OF A TRAVEL ISSUE WITH THIS...BUT SOME LIGHT ICING ON EXPOSED SURFACES WILL BE POSSIBLE THROUGH LATE MORNING UNTIL TEMPERATURES BUMP UP INTO THE UPPER 30S. HAVE ISSUED AN SPS TO ADDRESS THIS. THE SURFACE LOW WILL LIFT NORTHEAST ALONG THE I-71 CORRIDOR THROUGH THIS AFTERNOON. ALONG AND SOUTHEAST OF THIS WHERE WE WILL GET INTO A BIT OF A WARM SECTOR...THE RAP CONTINUES TO SHOW SOME WEAK INSTABILITIES OF GENERALLY 500 J/KG OR LESS DEVELOPING THROUGH LATE MORNING INTO MID AFTERNOON. THIS COULD LEAD TO SOME ISOLATED THUNDERSTORM DEVELOPMENT AS WE HEAD INTO THE AFTERNOON. THE BETTER INSTABILITY WILL NOT BE COMPLETELY SYNCED UP WITH THE BETTER SHEAR PROFILES WHICH WILL BE SHIFTING OFF TO THE NORTHEAST THROUGH EARLY AFTERNOON. HOWEVER..ALONG THE INTERFACE OF THE INCREASING INSTABILITY AND DECREASING SHEAR...IT WILL BE TOUGH TO RULE OUT A FEW STRONG TO SEVERE STORMS WITH EVEN AN ISOLATED TORNADO POSSIBLE. THE BEST CHANCE FOR THIS WOULD LIKELY BE ACROSS OUR FAR SOUTHEAST...WHERE THE BEST INSTABILITY SHOULD EXIST. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/... AS THE LOW CROSSES THROUGH NORTHERN OHIO THIS EVENING COLDER AIR WILL BE USHERED IN ON WESTERLY WINDS AND RAIN WILL CHANGE OVER TO SNOW. ACCUMULATIONS WILL BE LIMITED GIVEN THE WARM AND WET GROUND BUT THE POTENTIAL FOR 1-3 INCHES OF ACCUMULATION IS EXPECTED GIVEN THE TEMPERATURE PROFILE AND EXPECTED QPF...WITH THE HIGHER AMOUNTS NOTED NORTH OF METROPOLITAN DAYTON. AS THE COLD AIR PUSHES IN....SOME WIND GUSTS TO 40 MPH WILL BE POSSIBLE TONIGHT INTO THURSDAY. COLD ADVECTION WILL LIKELY KEEP SOME FORM OF SNOW SHOWERS OVER THE REGION THURSDAY AND THEN TAPER OFF OVERNIGHT. NORTHWEST FLOW WILL TAP MOISTURE FROM LAKE MICHIGAN AND KEEP THE THREAT OF SNOW SHOWERS IN THE FORECAST FOR FRIDAY AFTERNOON. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... THE EXTENDED FORECAST PERIOD WILL BEGIN WITH A SHARP TROUGH DEVELOPING IN THE FAR WESTERN STATES...WITH BROAD RIDGING ACROSS THE EASTERN TWO THIRDS OF THE COUNTRY. SURFACE HIGH PRESSURE WILL BE CENTERED OVER THE LOWER MISSISSIPPI VALLEY...MOVING EAST-SOUTHEAST AND GRAZING PAST THE OHIO VALLEY AND ILN FORECAST AREA. WHILE THERE IS A SLIGHT CHANCE THAT SOME FLURRIES OR LIGHT SNOW SHOWERS COULD BE CONTINUING WITHIN THE MIXED BOUNDARY LAYER ON FRIDAY MORNING...A DRY FORECAST WILL BE MAINTAINED FOR NOW. A THICK STRATOCUMULUS DECK LOOKS PRETTY LIKELY TO EXIST...AND THIS MAY NOT CLEAR UNTIL THE EVENING...WHEN WARM ADVECTION ALOFT BEGINS. A WEAK SHORTWAVE WILL MOVE THROUGH THE REGION FRIDAY NIGHT AND SATURDAY...BUT WITH VERY LITTLE MOISTURE...AND DRY CONDITIONS ARE EXPECTED. THE WARM ADVECTION WILL BEGIN TO INCREASE BY SATURDAY...WITH RIDGING BUILDING IN FOR THE SOUTHEASTERN STATES...AND A SHIFT TO SOUTHWESTERLY FLOW IN THE LOWER LEVELS OF THE ATMOSPHERE. IN FACT...SOME GUSTY CONDITIONS COULD BE POSSIBLE ON BOTH SATURDAY AND SUNDAY...WITH A TIGHTENING PRESSURE GRADIENT ACROSS THE MIDDLE MISSISSIPPI VALLEY AND INTO THE SOUTHERN GREAT LAKES REGION. AS RIDGING MOVES TO THE EAST...THE NEXT SHORTWAVE FORECAST TO AFFECT THE OHIO VALLEY IS EXPECTED TO MOVE THROUGH ON SUNDAY NIGHT. OVERALL TIMING AND PLACEMENT ALIGNMENT ON THE 06Z/12Z GFS AND 00Z/12Z ECMWF ARE GOOD...BUT UNSURPRISINGLY...DETAILS ON THE SPEED OF THE WAVE AND THE STRENGTH OF A DEVELOPING SURFACE LOW ARE IN MUCH POORER AGREEMENT. AFTER A COUPLE DAYS OF WARM ADVECTION...WHATEVER PRECIPITATION OCCURS SHOULD START AS RAIN...AND MAY STAY THAT WAY IN THE SOUTHERN AND SOUTHEASTERN SECTIONS OF THE FORECAST AREA. A MIX WITH SNOW WILL BE MORE LIKELY FURTHER TO THE NORTH. FOR MONDAY AND BEYOND...MODEL DIFFERENCES BECOME TOO LARGE TO ACCURATELY PREDICT A SPECIFIC DETERMINISTIC RESULT. THERE IS SIGNIFICANT DISAGREEMENT ON HOW FAR SOUTH A COLD FRONT IS ABLE TO TRAVEL ON MONDAY AND MONDAY NIGHT...AND THE PROGRESSION OF UPSTREAM TROUGHING BEYOND THAT POINT IS IN SIGNIFICANT DISAGREEMENT. AFTER MONDAY...500MB GFSE PERTURBATIONS BECOME COMPLETELY MISALIGNED AND OUT OF PHASE. THUS...SPECIFICS IN THE FORECAST BEYOND MONDAY ARE VERY LOW IN CONFIDENCE. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... SRN EDGE OF THE OVERRUNNING RAIN IS WORKING NORTH QUICKER THAN EXPECTED. CIGS AND VSBYS SHOULD GO VFR FROM SOUTH TO NORTH THIS MORNING AS THE STEADY RAIN ENDS AHEAD OF THE SFC LOW. WITH THE PASSAGE OF THE LOW...ADDITIONAL SCT SHRA/TSRA ARE POSSIBLE DURING THE AFTN. AS THE LOW MOVES NE AFT 00Z...COLDER AIR WILL FILTER INTO THE REGION. SHRA WILL MIX WITH...THEN CHANGE TO SN. CIGS AND VSBYS WILL DROP TO IFR WITH THE CHANGE TO SNOW. WINDS WILL ALSO INCREASE FROM THE WEST TO NORTHWEST IN THE CAA. THE STEADY SNOW ON THE BACKSIDE OF THE SYSTEM WILL TRANSITION TO SNOW SHOWERS TOWARDS 12Z...ALLOWING CIGS AND VSBYS TO RISE SLIGHTLY. OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES ARE EXPECTED WITH PRECIPITATION INTO THURSDAY. MVFR CEILINGS MAY CONTINUE INTO FRIDAY. GUSTY WINDS OF 35 TO 40 KNOTS POSSIBLE WEDNESDAY NIGHT INTO THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...FLOOD WATCH THROUGH LATE TONIGHT FOR OHZ070>074-077>082-088. KY...FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ089>100. IN...FLOOD WATCH THROUGH LATE TONIGHT FOR INZ066-073>075-080. && $$ SYNOPSIS...FRANKS NEAR TERM...JGL SHORT TERM...FRANKS LONG TERM...HATZOS AVIATION...SITES
AREA FORECAST DISCUSSION
NWS Tulsa OK
1117 AM CST WED FEB 24 2016 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. MVFR ceilings will begin to clear out of NW Arkansas and all areas will be VFR after 21z. Wind gusts will subside late this afternoon, with another frontal passage tonight bringing a small increase in NW winds after 06z. && .PREV DISCUSSION... /ISSUED 1012 AM CST WED FEB 24 2016/ DISCUSSION... Departing upper level low continues to result in gusty northwest winds in much of the area with some low clouds persisting across NW Arkansas into far NE Oklahoma. Overall trend through today will be gradual clearing with decrease in wind speeds, especially by late afternoon. A few small changes made to reflect current trends but overall, the short term forecast is in good shape. PREV DISCUSSION... /ISSUED 539 AM CST WED FEB 24 2016/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. MVFR ceilings will persist into this afternoon at KFYV/KXNA/KROG. Otherwise, VFR conditions will prevail through the forecast period. Gusty northwest winds today will diminish this evening. PREV DISCUSSION... /ISSUED 308 AM CST WED FEB 24 2016/ DISCUSSION... Precipitation is beginning taper off across far eastern Oklahoma and western Arkansas this morning. Most of the precipitation has transitioned back to rain at all the observation stations across western Arkansas. The HRRR has the precipitation moving out of the forecast area by 10z. Will be cancelling the Winter Weather Advisory before 8 am expiration time. Same goes for the Wind Advisory. Have not seen any wind gusts in the 40 mph range in some time. Otherwise, skies will clear out from west to east across the area as the storm system currently over western Tennessee moves off to the north-northeast. A cold front will move through the region Tonight and will keep temperatures generally below normal for this time of year through Friday morning. A warm up ensues Friday and especially over the weekend as the low level winds become south-southwesterly. Another cold front moves through the region Sunday night with no precipitation expected. The next chance of showers and thunderstorms will come as we move into the Tue-Wed time frame as the next storm system approaches. TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. $$ && .PRELIMINARY POINT TEMPS/POPS... TUL 54 33 52 28 / 0 0 0 0 FSM 51 33 53 29 / 0 0 0 0 MLC 54 31 53 26 / 0 0 0 0 BVO 54 27 52 25 / 0 0 0 0 FYV 45 28 45 25 / 10 0 0 0 BYV 46 30 45 26 / 10 0 0 0 MKO 53 32 51 29 / 0 0 0 0 MIO 48 30 47 26 / 0 0 0 0 F10 55 33 52 29 / 0 0 0 0 HHW 56 34 55 29 / 0 0 0 0 && .TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. && $$ SHORT TERM...14 LONG TERM....07 AVIATION...14
AREA FORECAST DISCUSSION
NWS Tulsa OK
1012 AM CST WED FEB 24 2016 .DISCUSSION... Departing upper level low continues to result in gusty northwest winds in much of the area with some low clouds persisting across NW Arkansas into far NE Oklahoma. Overall trend through today will be gradual clearing with decrease in wind speeds, especially by late afternoon. A few small changes made to reflect current trends but overall, the short term forecast is in good shape. && .PREV DISCUSSION... /ISSUED 539 AM CST WED FEB 24 2016/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. MVFR ceilings will persist into this afternoon at KFYV/KXNA/KROG. Otherwise, VFR conditions will prevail through the forecast period. Gusty northwest winds today will diminish this evening. PREV DISCUSSION... /ISSUED 308 AM CST WED FEB 24 2016/ DISCUSSION... Precipitation is beginning taper off across far eastern Oklahoma and western Arkansas this morning. Most of the precipitation has transitioned back to rain at all the observation stations across western Arkansas. The HRRR has the precipitation moving out of the forecast area by 10z. Will be cancelling the Winter Weather Advisory before 8 am expiration time. Same goes for the Wind Advisory. Have not seen any wind gusts in the 40 mph range in some time. Otherwise, skies will clear out from west to east across the area as the storm system currently over western Tennessee moves off to the north-northeast. A cold front will move through the region Tonight and will keep temperatures generally below normal for this time of year through Friday morning. A warm up ensues Friday and especially over the weekend as the low level winds become south-southwesterly. Another cold front moves through the region Sunday night with no precipitation expected. The next chance of showers and thunderstorms will come as we move into the Tue-Wed time frame as the next storm system approaches. TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. $$ && .PRELIMINARY POINT TEMPS/POPS... TUL 54 33 52 28 / 0 0 0 0 FSM 51 33 53 29 / 0 0 0 0 MLC 54 31 53 26 / 0 0 0 0 BVO 54 27 52 25 / 0 0 0 0 FYV 45 28 45 25 / 10 0 0 0 BYV 46 30 45 26 / 10 0 0 0 MKO 53 32 51 29 / 0 0 0 0 MIO 48 30 47 26 / 0 0 0 0 F10 55 33 52 29 / 0 0 0 0 HHW 56 34 55 29 / 0 0 0 0 && .TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. && $$ SHORT TERM...14 LONG TERM....07
AREA FORECAST DISCUSSION
NWS Tulsa OK
539 AM CST WED FEB 24 2016 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. MVFR ceilings will persist into this afternoon at KFYV/KXNA/KROG. Otherwise, VFR conditions will prevail through the forecast period. Gusty northwest winds today will diminish this evening. && .PREV DISCUSSION... /ISSUED 308 AM CST WED FEB 24 2016/ DISCUSSION... Precipitation is beginning taper off across far eastern Oklahoma and western Arkansas this morning. Most of the precipitation has transitioned back to rain at all the observation stations across western Arkansas. The HRRR has the precipitation moving out of the forecast area by 10z. Will be cancelling the Winter Weather Advisory before 8 am expiration time. Same goes for the Wind Advisory. Have not seen any wind gusts in the 40 mph range in some time. Otherwise, skies will clear out from west to east across the area as the storm system currently over western Tennessee moves off to the north-northeast. A cold front will move through the region Tonight and will keep temperatures generally below normal for this time of year through Friday morning. A warm up ensues Friday and especially over the weekend as the low level winds become south-southwesterly. Another cold front moves through the region Sunday night with no precipitation expected. The next chance of showers and thunderstorms will come as we move into the Tue-Wed time frame as the next storm system approaches. && .TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. && $$ AVIATION...05
AREA FORECAST DISCUSSION
NWS Tulsa OK
308 AM CST WED FEB 24 2016 .DISCUSSION... Precipitation is beginning taper off across far eastern Oklahoma and western Arkansas this morning. Most of the precipitation has transitioned back to rain at all the observation stations across western Arkansas. The HRRR has the precipitation moving out of the forecast area by 10z. Will be cancelling the Winter Weather Advisory before 8 am expiration time. Same goes for the Wind Advisory. Have not seen any wind gusts in the 40 mph range in some time. Otherwise, skies will clear out from west to east across the area as the storm system currently over western Tennessee moves off to the north-northeast. A cold front will move through the region Tonight and will keep temperatures generally below normal for this time of year through Friday morning. A warm up ensues Friday and especially over the weekend as the low level winds become south-southwesterly. Another cold front moves through the region Sunday night with no precipitation expected. The next chance of showers and thunderstorms will come as we move into the Tue-Wed time frame as the next storm system approaches. && .PRELIMINARY POINT TEMPS/POPS... TUL 54 33 52 28 / 0 0 0 0 FSM 51 33 53 29 / 0 0 0 0 MLC 54 31 53 26 / 0 0 0 0 BVO 54 27 52 25 / 0 0 0 0 FYV 45 28 45 25 / 10 0 0 0 BYV 46 30 45 26 / 10 0 0 0 MKO 53 32 51 29 / 0 0 0 0 MIO 48 30 47 26 / 0 0 0 0 F10 55 33 52 29 / 0 0 0 0 HHW 56 34 55 29 / 0 0 0 0 && .TSA Watches/Warnings/Advisories... OK...NONE. AR...Winter Weather Advisory until 8 AM CST this morning for ARZ001- 002-010-011-019-020. Wind Advisory until 6 AM CST early this morning for ARZ001-002- 010-011-019-020-029. && $$ SHORT TERM...05 LONG TERM....10
AREA FORECAST DISCUSSION
NWS NORMAN OK
1135 PM CST TUE FEB 23 2016 .AVIATION... 2406/2506 TAFS... VFR CONDITIONS WILL PREVAIL WITH A BREEZY NORTH WIND. && .PREV DISCUSSION... /ISSUED 845 PM CST TUE FEB 23 2016/ UPDATE... MINOR ADJUSTMENTS MADE TO SKY, TD, WIND, AND TEMP GRIDS. PLEASE SEE THE DISCUSSION BELOW. DISCUSSION... PRECIPITATION CONTINUES TO DISSIPATE AND SHIFT EASTWARD WITH THE MID TO UPPER LOW EARLY THIS EVENING. SOME SNOW IS NOW BEING OBSERVED OVER EASTERN OK BUT SFC WETBULBS ARE TOO HIGH ACROSS OUR FA. DEWPOINTS HAVE DROPPED INTO THE TEENS ACROSS NW OK AND SKIES ARE ALSO BEGINNING TO CLEAR THERE SO EXPECT SOME MIN TEMPS TO DROP INTO THE 20S BY EARLY MORNING THERE AS WIND SPEEDS DECREASE. ADJUSTED WINDS THROUGH 12Z CLOSER TO THE HRRR OUTPUT SINCE IT APPEARS TO HAVE A DECENT HANDLE ON THEM. THE SAME WAS DONE FOR DEWPOINTS. ONLY MINOR ADJUSTMENTS TO TEMPS WERE MADE, SPECIFICALLY ACROSS NW OK. ALL UPDATED PRODUCTS HAVE BEEN SENT. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 34 57 32 53 / 10 0 0 0 HOBART OK 32 60 31 54 / 10 0 0 0 WICHITA FALLS TX 35 60 34 57 / 10 0 0 0 GAGE OK 26 59 26 53 / 0 0 0 0 PONCA CITY OK 32 55 30 50 / 10 0 0 0 DURANT OK 37 57 36 56 / 70 0 0 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
801 AM EST WED FEB 24 2016 .SYNOPSIS... A STRONG LOW PRESSURE SYSTEM OVER WESTERN TN/KY THIS MORNING WILL STRENGTHEN AS IT LIFTS NORTHEAST ACROSS THE UPPER OHIO VALLEY AND LOWER GREAT LAKES REGION. WIDESPREAD MODERATE TO LOCALLY HEAVY RAIN IS EXPECTED. STRONG TO POTENTIALLY DAMAGING WINDS ARE POSSIBLE FROM LATE THIS AFTERNOON INTO THE EVENING ALONG A FAST MOVING LINE OF HEAVY SHOWERS/THUNDERSTORMS. GUSTY NORTHWEST WINDS WILL DIRECT COLDER AIR INTO THE AREA BEHIND THE DEPARTING STORM SYSTEM FOR THE SECOND HALF OF THE WEEK. RAIN WILL MIX WITH AND CHANGE TO SNOW ON THURSDAY OVER WESTERN PENNSYLVANIA WITH A LIGHT ACCUMULATION BY FRIDAY MORNING. && .NEAR TERM /THROUGH TONIGHT/... MESO OBS/IRIS DATABASE STILL SHOWING SEVERAL SITES AT 30-33F AT 07Z BUT THE OVERALL TREND IS TO THE UPSIDE. CONSIDERED ENDING FZRA ADVY EARLY WITH FREEZING PCPN BEING HIGHLY LOCALIZED...BUT DECIDED TO LET IT RUN THE COURSE FOR NOW ESPECIALLY GIVEN DELAYS ALREADY IN EFFECT. HRRR KEEPS BAND OF STEADIER RAIN CURRENTLY OVER WRN PA WEST OF I-99 CORRIDOR THRU 12Z...LEAVING MUCH OF THE AREA IN RELATIVE PCPN MINIMUM WITH CONTINUED LIGHT RAIN/DRIZZLE THROUGH MID MORNING. THE WEDGE FRONT/LOW LEVEL CAD SHOULD ERODE FROM SOUTH- NORTH BY THE LATE AFTERNOON AS SUGGESTED BY THE HIRES NCAR ENS MEAN LIFTED INDEX. THE STABLE AIR BELOW TYPICALLY STUBBORN INVERSION WILL QUICKLY BE REPLACED BY WARM/MOIST AND MARGINALLY UNSTABLE AIRMASS /HIRES ENS MEAN MUCAPES AROUND 500-750 J/KG/ IN PLACE AHEAD OF APPROACHING COLD FRONT. EXPECT RAIN COVERAGE AND INTENSITY TO INCREASE BY THE AFTERNOON COINCIDENT WITH RAMP-UP OF LARGE SCALE FORCING ASSOCIATED WITH POWERFUL 100+KT MID/UPPER JET...AND ARRIVAL OF 1-1.5 INCH PWS VIA 60-70KT LOW LEVEL SOUTHERLY WINDS. THE ANOMALOUS MOISTURE VALUES COMBINED WITH STRONG DIFFLUENT FLOW ALOFT/BOUNDARY LAYER CONVERGENCE WILL SUPPORT POTENTIAL FOR ORGANIZED FRONTAL OR PRE- FRONTAL CONVECTION ALONG/AHEAD OF A STRONG COLD FRONT RACING EAST- NORTHEAST FROM THE SOUTHERN APPALACHIANS AND ACROSS THE MID ATLANTIC STATES. WHILE THE AREA OF PCPN WILL BE QUITE PROGRESSIVE...THE PATTERN IS FAVORABLE FOR LOCALIZED HEAVY RAIN RATES/FLOODING RISK ESPECIALLY WITH CENTRAL PA FFG VALUES RATHER LOW. THEREFORE WPC HAS MAINTAINED RISK FOR EXCESSIVE RAINFALL AND WILL CONTINUE TO HIGHLIGHT IN HWO. UTILIZED WPC GUIDANCE FOR QPF AMTS WHICH RANGE BTWN 0.75 INCHES IN THE LAURELS TO ~ 1.50 INCHES FOCUSED INTO THE THE SOUTHERN POCONOS/ENDLESS MTNS WHERE TERRAIN ENHANCEMENT WILL BE MAXIMIZED. THE VERY STRONG WIND FIELDS WILL SUPPORT AN IMPRESSIVE KINEMATIC ENVIRONMENT DURING THE LATE AFTERNOON AND EVENING HOURS WITH A LARGE AREA OF DEEP LAYER SHEAR GREATER THAN 60KT AND STORM MOTIONS LIKELY OVER 50KT. GIVEN THE MAGNITUDE OF THE FORCING/FLOW AND FAVORABLE HIGH SHEAR/LOW CAPE ENVIRONMENT...IT IS NOT SURPRISING TO SEE THE HIRES GUIDANCE DEPICT A LINE OF LOW TOPPED HEAVY SHOWERS/EMBEDDED TSTMS CROSSING THE CWA BTWN 21-03Z WITH THE PRIMARY SEVERE WX THREAT OF STRONG TO DAMAGING WIND GUSTS. WILL ALSO HIGHLIGHT THIS RISK IN HWO. HEAVY RAIN/SEVERE WX RISK SHOULD END BY MIDNIGHT WITH LINGERING LIGHT RAIN/SHOWERS INTO EARLY THURSDAY MORNING. SNOW MAY BEGIN TO MIX WITH RAIN OVER THE HIGHER TERRAIN ALONG THE WESTERN ALLEGHENIES AS COLDER AIR BEGINS TO FILTER IN BEHIND INCREASINGLY GUSTY NW WINDS. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... PERSISTENT/STRONG COLD ADVECTION WRAPPING INTO CENTRAL PA BEHIND THE DEPARTING STORM TRACKING INTO THE ST. LAWRENCE VALLEY SHOULD TRANSITION RAIN TO SNOW OVER THE WESTERN ALLEGHENIES ON THURSDAY. MARGINALLY WARM BLYR TEMPS AND ROAD SFC MAY BE A LIMITING FACTOR FOR ACCUMULATIONS INITIALLY. THE COMBINATION OF LAKE EFFECT/ENHANCED UPSLOPE SNOW AND DECAYING COMMA HEAD/DEFORMATION ZONE SHOULD YIELD A GENERAL 1-3 INCHES BY FRIDAY MORNING. WIND GUSTS IN THE 25 TO 35 MPH RANGE ARE LIKELY ON THURSDAY WITH PEAK GUSTS AROUND 40 MPH POSSIBLE ON THE RIDGES IN SOUTHWEST PA. LAKE EFFECT/UPSLOPE SNOW SHOWERS GRADUALLY TAPER DOWN ON FRIDAY AND COME TO AN END FRI NGT AS WEAK RIDGE OF HIGH PRESSURE SLIDES INTO THE AREA. && .LONG TERM /SATURDAY THROUGH TUESDAY/... TEMPERATURES SHOULD MODERATE NICELY SAT-SUN AS SW FLOW BRINGS MILDER AIR INTO THE AREA. MODEL CONSENSUS SHOWS LOW PRES TRACKING FROM THE MIDWEST ACROSS THE LOWER GREAT LAKES INTO NORTHERN NEW ENGLAND SUN-MON...BRINGING RISK OF RAIN/SNOW TO START NEXT WEEK. GFS/ECMWF DIVERGE ON THE SFC PATTERN TOWARD THE MIDDLE OF NEXT WEEK BUT NEITHER MODEL INDICATES ANY HIGH IMPACT WX SYSTEMS. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... AS A SERIES OF STORM SYSTEMS AFFECT MOVE TO THE NORTH...EXPECT WIDESPREAD IFR ACROSS THE REGION. CURRENTLY IFR IS AT ALL TAF SITES WITH CLOUDS AND RAIN MOVING IN FROM THE SOUTHWEST...WHICH SHOULD ENVELOP CENTRAL PA TODAY THROUGH AFTERNOON INTO EARLY EVENING. STEADIER/HEAVIER RAIN WILL ARRIVE THIS AFTERNOON AS A STRONGER STORM TRACKS NORTHEAST FROM THE OHIO VALLEY TOWARD THE EASTERN GREAT LAKES. THE OTHER CONCERN IS AS THE LOW LEVEL JET TRACKS INTO THE REGION LATE THIS MORNING...EARLY AFTERNOON. THERE WILL BE AN INCREASE IN LLWS. EXPECT WINDS ALOFT OF 60 TO 70 KTS AROUND 2KFT. THIS WIND SHEAR SHOULD BEGIN WEST TO EAST THROUGH 15Z...AND ENDING BETWEEN 00Z TO 03Z THURSDAY AS THE JET EXITS THE REGION. EXPECT CONDITIONS TO SLOWLY IMPROVE BETWEEN 03Z TO 09Z FROM THE SOUTH TO THE NORTH. IFR SHOULD IMPROVE TO MVFR BETWEEN 00Z TO 06Z AND FROM MVFR TO VFR BETWEEN 09Z TO 12Z THURSDAY. OUTLOOK... THU...WINDY. PM SHSN/REDUCED VSBYS POSS...MAINLY W MTNS. FRI...WINDY...ESP EAST. AM SHSN/REDUCED VSBY POSS W MTNS. SAT-SUN...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING RAIN ADVISORY UNTIL 8 AM EST THIS MORNING FOR PAZ005- 006-010>012-017>019-024>028-033>037-041-042-045-046-049>053- 058. && $$ SYNOPSIS...STEINBUGL NEAR TERM...STEINBUGL SHORT TERM...STEINBUGL LONG TERM...STEINBUGL AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
659 AM EST WED FEB 24 2016 .SYNOPSIS... A STRONG LOW PRESSURE SYSTEM OVER WESTERN TN/KY THIS MORNING WILL STRENGTHEN AS IT LIFTS NORTHEAST ACROSS THE UPPER OHIO VALLEY AND LOWER GREAT LAKES REGION. WIDESPREAD MODERATE TO LOCALLY HEAVY RAIN IS EXPECTED. STRONG TO POTENTIALLY DAMAGING WINDS ARE POSSIBLE FROM LATE THIS AFTERNOON INTO THE EVENING ALONG A FAST MOVING LINE OF HEAVY SHOWERS/THUNDERSTORMS. GUSTY NORTHWEST WINDS WILL DIRECT COLDER AIR INTO THE AREA BEHIND THE DEPARTING STORM SYSTEM FOR THE SECOND HALF OF THE WEEK. RAIN WILL MIX WITH AND CHANGE TO SNOW ON THURSDAY OVER WESTERN PENNSYLVANIA WITH A LIGHT ACCUMULATION BY FRIDAY MORNING. && .NEAR TERM /THROUGH TONIGHT/... 630AM UPDATE...ICING RISK NOW VERY LIMITED TO HIGHEST RIDGES WEST OF THE I-99 CORRIDOR INTO RURAL NCENTRAL PA. DON`T FEEL IT WILL NEED TO BE EXTENDED GIVEN LIMITED COVERAGE/IMPACT AND THEREFORE ANTICIPATE THE HEADLINE ENDING ON SCHEDULE. MESO OBS/IRIS DATABASE STILL SHOWING SEVERAL SITES AT 30-33F AT 07Z BUT THE OVERALL TREND IS TO THE UPSIDE. CONSIDERED ENDING FZRA ADVY EARLY WITH FREEZING PCPN BEING HIGHLY LOCALIZED...BUT DECIDED TO LET IT RUN THE COURSE FOR NOW ESPECIALLY GIVEN DELAYS ALREADY IN EFFECT. HRRR KEEPS BAND OF STEADIER RAIN CURRENTLY OVER WRN PA WEST OF I-99 CORRIDOR THRU 12Z...LEAVING MUCH OF THE AREA IN RELATIVE PCPN MINIMUM WITH CONTINUED LIGHT RAIN/DRIZZLE THROUGH MID MORNING. THE WEDGE FRONT/LOW LEVEL CAD SHOULD ERODE FROM SOUTH- NORTH BY THE LATE AFTERNOON AS SUGGESTED BY THE HIRES NCAR ENS MEAN LIFTED INDEX. THE STABLE AIR BELOW TYPICALLY STUBBORN INVERSION WILL QUICKLY BE REPLACED BY WARM/MOIST AND MARGINALLY UNSTABLE AIRMASS /HIRES ENS MEAN MUCAPES AROUND 500-750 J/KG/ IN PLACE AHEAD OF APPROACHING COLD FRONT. EXPECT RAIN COVERAGE AND INTENSITY TO INCREASE BY THE AFTERNOON COINCIDENT WITH RAMP-UP OF LARGE SCALE FORCING ASSOCIATED WITH POWERFUL 100+KT MID/UPPER JET...AND ARRIVAL OF 1-1.5 INCH PWS VIA 60-70KT LOW LEVEL SOUTHERLY WINDS. THE ANOMALOUS MOISTURE VALUES COMBINED WITH STRONG DIFFLUENT FLOW ALOFT/BOUNDARY LAYER CONVERGENCE WILL SUPPORT POTENTIAL FOR ORGANIZED FRONTAL OR PRE- FRONTAL CONVECTION ALONG/AHEAD OF A STRONG COLD FRONT RACING EAST- NORTHEAST FROM THE SOUTHERN APPALACHIANS AND ACROSS THE MID ATLANTIC STATES. WHILE THE AREA OF PCPN WILL BE QUITE PROGRESSIVE...THE PATTERN IS FAVORABLE FOR LOCALIZED HEAVY RAIN RATES/FLOODING RISK ESPECIALLY WITH CENTRAL PA FFG VALUES RATHER LOW. THEREFORE WPC HAS MAINTAINED RISK FOR EXCESSIVE RAINFALL AND WILL CONTINUE TO HIGHLIGHT IN HWO. UTILIZED WPC GUIDANCE FOR QPF AMTS WHICH RANGE BTWN 0.75 INCHES IN THE LAURELS TO ~ 1.50 INCHES FOCUSED INTO THE THE SOUTHERN POCONOS/ENDLESS MTNS WHERE TERRAIN ENHANCEMENT WILL BE MAXIMIZED. THE VERY STRONG WIND FIELDS WILL SUPPORT AN IMPRESSIVE KINEMATIC ENVIRONMENT DURING THE LATE AFTERNOON AND EVENING HOURS WITH A LARGE AREA OF DEEP LAYER SHEAR GREATER THAN 60KT AND STORM MOTIONS LIKELY OVER 50KT. GIVEN THE MAGNITUDE OF THE FORCING/FLOW AND FAVORABLE HIGH SHEAR/LOW CAPE ENVIRONMENT...IT IS NOT SURPRISING TO SEE THE HIRES GUIDANCE DEPICT A LINE OF LOW TOPPED HEAVY SHOWERS/EMBEDDED TSTMS CROSSING THE CWA BTWN 21-03Z WITH THE PRIMARY SEVERE WX THREAT OF STRONG TO DAMAGING WIND GUSTS. WILL ALSO HIGHLIGHT THIS RISK IN HWO. HEAVY RAIN/SEVERE WX RISK SHOULD END BY MIDNIGHT WITH LINGERING LIGHT RAIN/SHOWERS INTO EARLY THURSDAY MORNING. SNOW MAY BEGIN TO MIX WITH RAIN OVER THE HIGHER TERRAIN ALONG THE WESTERN ALLEGHENIES AS COLDER AIR BEGINS TO FILTER IN BEHIND INCREASINGLY GUSTY NW WINDS. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... PERSISTENT/STRONG COLD ADVECTION WRAPPING INTO CENTRAL PA BEHIND THE DEPARTING STORM TRACKING INTO THE ST. LAWRENCE VALLEY SHOULD TRANSITION RAIN TO SNOW OVER THE WESTERN ALLEGHENIES ON THURSDAY. MARGINALLY WARM BLYR TEMPS AND ROAD SFC MAY BE A LIMITING FACTOR FOR ACCUMULATIONS INITIALLY. THE COMBINATION OF LAKE EFFECT/ENHANCED UPSLOPE SNOW AND DECAYING COMMA HEAD/DEFORMATION ZONE SHOULD YIELD A GENERAL 1-3 INCHES BY FRIDAY MORNING. WIND GUSTS IN THE 25 TO 35 MPH RANGE ARE LIKELY ON THURSDAY WITH PEAK GUSTS AROUND 40 MPH POSSIBLE ON THE RIDGES IN SOUTHWEST PA. LAKE EFFECT/UPSLOPE SNOW SHOWERS GRADUALLY TAPER DOWN ON FRIDAY AND COME TO AN END FRI NGT AS WEAK RIDGE OF HIGH PRESSURE SLIDES INTO THE AREA. && .LONG TERM /SATURDAY THROUGH TUESDAY/... TEMPERATURES SHOULD MODERATE NICELY SAT-SUN AS SW FLOW BRINGS MILDER AIR INTO THE AREA. MODEL CONSENSUS SHOWS LOW PRES TRACKING FROM THE MIDWEST ACROSS THE LOWER GREAT LAKES INTO NORTHERN NEW ENGLAND SUN-MON...BRINGING RISK OF RAIN/SNOW TO START NEXT WEEK. GFS/ECMWF DIVERGE ON THE SFC PATTERN TOWARD THE MIDDLE OF NEXT WEEK BUT NEITHER MODEL INDICATES ANY HIGH IMPACT WX SYSTEMS. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... AS A SERIES OF STORM SYSTEMS AFFECT MOVE TO THE NORTH...EXPECT WIDESPREAD IFR ACROSS THE REGION. CURRENTLY IFR IS AT ALL TAF SITES EXCEPT UNV AND IPT WHICH ARE MVFR. CLOUDS AND RAIN MOVING IN FROM THE SOUTHWEST...WHICH SHOULD ENVELOP CENTRAL PA...ALLOWING FOR IFR BY 10Z. THE BIGGEST ISSUE INTO THE OVERNIGHT...BEYOND THE LOW CEILINGS AND AREAS OF FOG...WILL BE THE POSSIBILITY OF POCKETS OF FREEZING DRIZZLE/RAIN. TEMPERATURES OVER MUCH OF CENTRAL PA ARE NOT FAR FROM FREEZING...ANY DROP OFF AT ALL OVERNIGHT WILL RESULT IN LOCALIZED POCKETS OF LIGHT ICING. STEADIER/HEAVIER RAIN WILL ARRIVE LATE TONIGHT INTO EARLY WEDNESDAY MORNING AS A STRONGER STORM TRACKS NORTHEAST FROM THE OHIO VALLEY TOWARD THE EASTERN GREAT LAKES. THE OTHER CONCERN IS AS THE LOW LEVEL JET TRACKS INTO THE REGION EARLY WEDNESDAY...THERE WILL BE AN INCREASE IN LLWS. EXPECT WINDS ALOFT OF 60 TO 70 KTS AROUND 2KFT. THIS WIND SHEAR SHOULD BEGIN WEST TO EAST BETWEEN 13Z TO 15Z...AND ENDING BETWEEN 00Z TO 03Z THURSDAY AS THE JET EXITS THE REGION. OUTLOOK... WED NGT...WINDY WITH RAIN/LOW CIGS LIKELY. THU...WINDY. PM SHSN/REDUCED VSBYS POSS...MAINLY W MTNS. FRI...WINDY...ESP EAST. AM SHSN/REDUCED VSBY POSS W MTNS. SAT-SUN...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING RAIN ADVISORY UNTIL 8 AM EST THIS MORNING FOR PAZ005- 006-010>012-017>019-024>028-033>037-041-042-045-046-049>053- 058. && $$ SYNOPSIS...STEINBUGL NEAR TERM...STEINBUGL SHORT TERM...STEINBUGL LONG TERM...STEINBUGL AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
411 AM EST WED FEB 24 2016 .SYNOPSIS... A STRONG LOW PRESSURE SYSTEM OVER WESTERN TN/KY THIS MORNING WILL STRENGTHEN AS IT LIFTS NORTHEAST ACROSS THE UPPER OHIO VALLEY AND LOWER GREAT LAKES REGION. WIDESPREAD MODERATE TO LOCALLY HEAVY RAIN IS EXPECTED. STRONG TO POTENTIALLY DAMAGING WINDS ARE POSSIBLE FROM LATE THIS AFTERNOON INTO THE EVENING ALONG A FAST MOVING LINE OF HEAVY SHOWERS/THUNDERSTORMS. GUSTY NORTHWEST WINDS WILL DIRECT COLDER AIR INTO THE AREA BEHIND THE DEPARTING STORM SYSTEM FOR THE SECOND HALF OF THE WEEK. RAIN WILL MIX WITH AND CHANGE TO SNOW ON THURSDAY OVER WESTERN PENNSYLVANIA WITH A LIGHT ACCUMULATION BY FRIDAY MORNING. && .NEAR TERM /THROUGH TONIGHT/... MESO OBS/IRIS DATABASE STILL SHOWING SEVERAL SITES AT 30-33F AT 07Z BUT THE OVERALL TREND IS TO THE UPSIDE. CONSIDERED ENDING FZRA ADVY EARLY WITH FREEZING PCPN BEING HIGHLY LOCALIZED...BUT DECIDED TO LET IT RUN THE COURSE FOR NOW ESPECIALLY GIVEN DELAYS ALREADY IN EFFECT. HRRR KEEPS BAND OF STEADIER RAIN CURRENTLY OVER WRN PA WEST OF I-99 CORRIDOR THRU 12Z...LEAVING MUCH OF THE AREA IN RELATIVE PCPN MINIMUM WITH CONTINUED LIGHT RAIN/DRIZZLE THROUGH MID MORNING. THE WEDGE FRONT/LOW LEVEL CAD SHOULD ERODE FROM SOUTH- NORTH BY THE LATE AFTERNOON AS SUGGESTED BY THE HIRES NCAR ENS MEAN LIFTED INDEX. THE STABLE AIR BELOW TYPICALLY STUBBORN INVERSION WILL QUICKLY BE REPLACED BY WARM/MOIST AND MARGINALLY UNSTABLE AIRMASS /HIRES ENS MEAN MUCAPES AROUND 500-750 J/KG/ IN PLACE AHEAD OF APPROACHING COLD FRONT. EXPECT RAIN COVERAGE AND INTENSITY TO INCREASE BY THE AFTERNOON COINCIDENT WITH RAMP-UP OF LARGE SCALE FORCING ASSOCIATED WITH POWERFUL 100+KT MID/UPPER JET...AND ARRIVAL OF 1-1.5 INCH PWS VIA 60-70KT LOW LEVEL SOUTHERLY WINDS. THE ANOMALOUS MOISTURE VALUES COMBINED WITH STRONG DIFFLUENT FLOW ALOFT/BOUNDARY LAYER CONVERGENCE WILL SUPPORT POTENTIAL FOR ORGANIZED FRONTAL OR PRE- FRONTAL CONVECTION ALONG/AHEAD OF A STRONG COLD FRONT RACING EAST- NORTHEAST FROM THE SOUTHERN APPALACHIANS AND ACROSS THE MID ATLANTIC STATES. WHILE THE AREA OF PCPN WILL BE QUITE PROGRESSIVE...THE PATTERN IS FAVORABLE FOR LOCALIZED HEAVY RAIN RATES/FLOODING RISK ESPECIALLY WITH CENTRAL PA FFG VALUES RATHER LOW. THEREFORE WPC HAS MAINTAINED RISK FOR EXCESSIVE RAINFALL AND WILL CONTINUE TO HIGHLIGHT IN HWO. UTILIZED WPC GUIDANCE FOR QPF AMTS WHICH RANGE BTWN 0.75 INCHES IN THE LAURELS TO ~ 1.50 INCHES FOCUSED INTO THE THE SOUTHERN POCONOS/ENDLESS MTNS WHERE TERRAIN ENHANCEMENT WILL BE MAXIMIZED. THE VERY STRONG WIND FIELDS WILL SUPPORT AN IMPRESSIVE KINEMATIC ENVIRONMENT DURING THE LATE AFTERNOON AND EVENING HOURS WITH A LARGE AREA OF DEEP LAYER SHEAR GREATER THAN 60KT AND STORM MOTIONS LIKELY OVER 50KT. GIVEN THE MAGNITUDE OF THE FORCING/FLOW AND FAVORABLE HIGH SHEAR/LOW CAPE ENVIRONMENT...IT IS NOT SURPRISING TO SEE THE HIRES GUIDANCE DEPICT A LINE OF LOW TOPPED HEAVY SHOWERS/EMBEDDED TSTMS CROSSING THE CWA BTWN 21-03Z WITH THE PRIMARY SEVERE WX THREAT OF STRONG TO DAMAGING WIND GUSTS. WILL ALSO HIGHLIGHT THIS RISK IN HWO. HEAVY RAIN/SEVERE WX RISK SHOULD END BY MIDNIGHT WITH LINGERING LIGHT RAIN/SHOWERS INTO EARLY THURSDAY MORNING. SNOW MAY BEGIN TO MIX WITH RAIN OVER THE HIGHER TERRAIN ALONG THE WESTERN ALLEGHENIES AS COLDER AIR BEGINS TO FILTER IN BEHIND INCREASINGLY GUSTY NW WINDS. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... PERSISTENT/STRONG COLD ADVECTION WRAPPING INTO CENTRAL PA BEHIND THE DEPARTING STORM TRACKING INTO THE ST. LAWRENCE VALLEY SHOULD TRANSITION RAIN TO SNOW OVER THE WESTERN ALLEGHENIES ON THURSDAY. MARGINALLY WARM BLYR TEMPS AND ROAD SFC MAY BE A LIMITING FACTOR FOR ACCUMULATIONS INITIALLY. THE COMBINATION OF LAKE EFFECT/ENHANCED UPSLOPE SNOW AND DECAYING COMMA HEAD/DEFORMATION ZONE SHOULD YIELD A GENERAL 1-3 INCHES BY FRIDAY MORNING. WIND GUSTS IN THE 25 TO 35 MPH RANGE ARE LIKELY ON THURSDAY WITH PEAK GUSTS AROUND 40 MPH POSSIBLE ON THE RIDGES IN SOUTHWEST PA. LAKE EFFECT/UPSLOPE SNOW SHOWERS GRADUALLY TAPER DOWN ON FRIDAY AND COME TO AN END FRI NGT AS WEAK RIDGE OF HIGH PRESSURE SLIDES INTO THE AREA. && .LONG TERM /SATURDAY THROUGH TUESDAY/... TEMPERATURES SHOULD MODERATE NICELY SAT-SUN AS SW FLOW BRINGS MILDER AIR INTO THE AREA. MODEL CONSENSUS SHOWS LOW PRES TRACKING FROM THE MIDWEST ACROSS THE LOWER GREAT LAKES INTO NORTHERN NEW ENGLAND SUN-MON...BRINGING RISK OF RAIN/SNOW TO START NEXT WEEK. GFS/ECMWF DIVERGE ON THE SFC PATTERN TOWARD THE MIDDLE OF NEXT WEEK BUT NEITHER MODEL INDICATES ANY HIGH IMPACT WX SYSTEMS. && .AVIATION /07Z WEDNESDAY THROUGH SUNDAY/... AS A SERIES OF STORM SYSTEMS AFFECT MOVE TO THE NORTH...EXPECT WIDESPREAD IFR ACROSS THE REGION. CURRENTLY IFR IS AT ALL TAF SITES EXCEPT UNV AND IPT WHICH ARE MVFR. CLOUDS AND RAIN MOVING IN FROM THE SOUTHWEST...WHICH SHOULD ENVELOP CENTRAL PA...ALLOWING FOR IFR BY 10Z. THE BIGGEST ISSUE INTO THE OVERNIGHT...BEYOND THE LOW CEILINGS AND AREAS OF FOG...WILL BE THE POSSIBILITY OF POCKETS OF FREEZING DRIZZLE/RAIN. TEMPERATURES OVER MUCH OF CENTRAL PA ARE NOT FAR FROM FREEZING...ANY DROP OFF AT ALL OVERNIGHT WILL RESULT IN LOCALIZED POCKETS OF LIGHT ICING. STEADIER/HEAVIER RAIN WILL ARRIVE LATE TONIGHT INTO EARLY WEDNESDAY MORNING AS A STRONGER STORM TRACKS NORTHEAST FROM THE OHIO VALLEY TOWARD THE EASTERN GREAT LAKES. THE OTHER CONCERN IS AS THE LOW LEVEL JET TRACKS INTO THE REGION EARLY WEDNESDAY...THERE WILL BE AN INCREASE IN LLWS. EXPECT WINDS ALOFT OF 60 TO 70 KTS AROUND 2KFT. THIS WIND SHEAR SHOULD BEGIN WEST TO EAST BETWEEN 13Z TO 15Z...AND ENDING BETWEEN 00Z TO 03Z THURSDAY AS THE JET EXITS THE REGION. OUTLOOK... WED NGT...WINDY WITH RAIN/LOW CIGS LIKELY. THU...WINDY. PM SHSN/REDUCED VSBYS POSS...MAINLY W MTNS. FRI...WINDY...ESP EAST. AM SHSN/REDUCED VSBY POSS W MTNS. SAT-SUN...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING RAIN ADVISORY UNTIL 8 AM EST THIS MORNING FOR PAZ005- 006-010>012-017>019-024>028-033>037-041-042-045-046-049>053- 058. && $$ SYNOPSIS...STEINBUGL NEAR TERM...STEINBUGL SHORT TERM...STEINBUGL LONG TERM...STEINBUGL AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
110 PM EST WED FEB 24 2016 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL MOVE NORTHEAST ACROSS THE TENNESSEE VALLEY TODAY AND SWING A COLD FRONT OVER THE CAROLINAS AND NORTHEAST GEORGIA. DRY AND SEASONABLE HIGH PRESSURE WILL BUILD IN FROM THE WEST FRIDAY AND REMAIN THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1245 AM...WITH STRONG LLVL WINDS AND DEEP MIXING...MUCH OF THE PIEDMONT IS REALIZING WIND GUSTS IN THE 35-45 KT RANGE...OCCASIONALLY AS HIGH AS 48 KTS. THERE HAVE BEEN NUMEROUS REPORTS OF TREES FALLING DOWN AND POWER OUTAGES. GIVEN THE WET SOILS LOOSENING ROOTS...EVEN SUB-WARNING WINDS ARE KNOCKING DOWN MORE TREES THAN USUAL. SO HAVE OPTED TO UPGRADE THE WIND ADVISORY TO A HIGH WIND WARNING FOR ALL THE PIEDMONT AND THE SOUTHWEST NC MTNS UNTIL 7 PM. WINDS WILL REMAIN GUSTY INTO THE EVENING...SO THE WIND ADVISORIES STILL LOOK GOOD THRU MIDNIGHT. AS FOR CONVECTION...AS THE HIGH RES MODELS INDICATED...THE LINE OF STORMS ARE QUICKLY CROSSING THE REMAINDER OF OUR CWFA...ALREADY EAST OF I-77. A TORNADO WATCH WAS ISSUED FOR THIS LINE...AND SHOULD BE ABLE TO BE CLEARED SOON. AS FOR THE FLOOD WATCH...THE HEAVY RAIN/FLASH FLOOD THREAT IS WANING...BUT WILL LEAVE UP THE PORTION ALONG AND EAST OF THE LINE OF CONVECTION. THE REST OF THE WATCH WAS CANCELED. AS OF 1000 AM...THE WEDGE FRONT CONTINUES TO RETREAT AS EXPECTED...WITH JUST THE NC FOOTHILLS AND PORTIONS OF THE NW PIEDMONT STILL IN THE WEDGE. THE LAPS AND RAP CAPE ANALYSES SHOWING THE UNCOVERED AIR MASS IS BECOMING UNSTABLE...WITH 500-1000 J/KG OF SBCAPE...ACROSS THE UPPER SAVANNAH VALLEY. THIS POCKET OF BEST INSTABILITY IS LINING UP WITH DEVELOPING LINE OF CONVECTION FROM THE NC ESCARPMENT TO AROUND GREENWOOD SC. THIS BROKEN LINE WILL LIKELY INTENSIFY AS IT TRACKS EAST...WITH PLENTY OF SHEAR FOR ROTATING UPDRAFTS AND WIND/HAIL/TORNADO THREAT DEVELOPING. THE LATEST DAY 1 CONVECTIVE OUTLOOK HAS SHIFTED THE SLGT RISK TO THE EAST...NOW JUST BARELY CLIPPING THE EASTERN TIER OF OUR COUNTIES. THIS AREA IS WHERE THE INSTABILITY AND SHEAR WILL LINE UP BEST FOR MORE ROBUST SUPERCELLS. THE RAP 0-1 KM EHI OVER 1 EAST OF I-77 EARLY THIS AFTERNOON. WILL KEEP MENTION OF SEVERE FOR THE I-77 CORRIDOR. TO THE WEST...THERE IS A NON-ZERO SEVERE THREAT...BUT THE BIGGER THREAT LOOKS TO BE WINDS...BOTH IN CONVECTION AND JUST WITH MIXING. THE LATEST NAM AND HIGH RES/NEAR TERM GUIDANCE STILL INDICATING SOLID 30-40 MPH GUSTS ACRS THE ENTIRE CWFA FROM MIDDAY THRU THE EVENING...WITH AN OCCASIONAL HIGHER GUST POSSIBLE. THE WIND HEADLINES LOOK ON TRACK. THE ENVIRONMENT ALONG AND AHEAD OF THE ADVANCING COLD FRONT APPEARS VERY INTERESTING AFTER MID MORNING. NAM FORECAST SOUNDINGS MAINTAIN A VERY LOW LFC...GENERALLY 2 KFT. HELICITY BETWEEN 0-1 KM IS FORECAST TO RANGE FROM 250-300 M2/S2 ACROSS THE PIEDMONT AND EASTERN FOOTHILLS. INSTABILITY IS MUCH MORE UNCERTAIN...HOWEVER...IT SHOULD EASILY INCREASE ACROSS THE NC PIEDMONT AND NE UPSTATE OF SC IN THE WAKE OF THE DEPARTING WEDGE BOUNDARY...REACHING 600-900 J/KG. IN FACT...MID DAY VALUES OF EHI OVER KCLT NEAR 2.5 ACCORDING TO THE NAM. IN ADDITION...GFS360 INDICATES THAT A BELT OF H5 Q-VECTOR CONVERGENCE WILL SWEEP ACROSS THE I-77 CORRIDOR DURING THE LATE MORNING TO MID AFTER HOURS. CAMS SIMULATED REFLECTIVITY APPEAR VERY REALISTIC GIVEN THE EXPECTED ENVIRONMENT...SHOWING LIMITED DEVELOPMENT ACROSS THE MTNS AND FOOTHILLS. HOWEVER...BY EARLY AFTERNOON...A NORTH-SOUTH LINE OF TSRA DEVELOPS ALONG THE COLD FRONT OVER THE I-77 CORRIDOR. THIS WILL BE THE FEATURE TO WATCH...POSSIBLY RESULTING IN DAMAGING WINDS...HAIL...AND A ISOLATED TORNADO. WE WILL CONTINUE TO HIGHLIGHT SVR TSRA IN THE HWO AND THE FORECAST. THE SECOND HAZARD IS EXCESSIVE RAINFALL. SO FAR...IT APPEARS THAT THE SQUALL LINE ACROSS THE DEEP SOUTH IS BLOCKING THE DEEPEST MOISTURE FROM REACHING THE FORECAST AREA. HOWEVER...CONVECTIVE DOWNPOURS AND PRESENT HIGH STREAM FLOWS WOULD YIELD EASY CONDITIONS FOR FLASH FLOODING TO DEVELOP...NO CHANGES TO THE FLASH FLOOD WATCH. THE SATURATED GROUND AND GUSTY WINDS WILL LIKELY YIELD DOWNED TREES TODAY AND THIS EVENING...I WILL KEEP WIND HEADLINES THROUGH THIS MORNING. EXTENDING WIND ADVISORY ACROSS THE MTNS TO MATCH FOOTHILL AND PIEDMONT ADVISORY THROUGH MIDNIGHT. TONIGHT...WRAP-AROUND MOISTURE...CAA...AND GUSTY NW WINDS WILL SUPPORT UPSLOPE PRECIPITATION ACROSS THE NC MTNS. GIVEN THE TIMING THE CAA...PRECIP WILL CHANGE OVER THE -SN AROUND MIDNIGHT. RELATIVELY DEEP MOISTURE AND STRONG FLOW WILL SUPPORT ACCUMULATING SHSN ACROSS THE MTNS THROUGH THE LATE NIGHT HOURS. IT IS POSSIBLE MANY AREAS ALONG THE TN LINE WILL SEE AROUND TWO INCHES ON THE GROUND BY SUNRISE THURSDAY. ACCUMULATING SNOWFALL WILL CONTINUE INTO THURSDAY. WE WILL POST A WINTER WEATHER ADVISORY STARTING AT MIDNIGHT. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 130 AM EST WEDNESDAY...FAIRLY STRAIGHT-FORWARD LOOKING SITUATION FOR THE REST OF THE WORK WEEK...DOMINATED MAINLY BY AN UPPER TROF LEFT BEHIND IN THE WAKE OF THE DEPARTING STORM SYSTEM. THE MAIN ISSUE WILL BE PRECIP PRODUCTION ACROSS THE NC MOUNTAINS... MAINLY NEAR THE TN BORDER...AT LEAST THROUGH THURSDAY AND THURSDAY NIGHT. THE OPERATIONAL MODELS AGREE THAT MOISTURE WILL BE RELATIVELY DEEP THROUGH AT LEAST THURSDAY EVENING...WHILE THICKNESS/FCST SOUNDINGS SUPPORT PRECIP FALLING ALMOST ENTIRELY AS SNOW EVEN ON THURSDAY AFTERNOON WHEN TEMPS MAY CLIMB CLOSE TO 40 DEGREES IN SOME VALLEY LOCATIONS. THERE ARE SOME CONFLICTING SIGNALS. ON THE ONE HAND...THE FLOW IS MORE WESTERLY THROUGH THE DAYTIME HOURS ON THURSDAY...ALTHOUGH IT DOES VEER AROUND TO A MORE NW DIRECTION AROUND 00Z FRIDAY. ON THE OTHER HAND...WHAT THE SITUATION LACKS IN MECHANICAL FORCING WILL BE MADE UP BY SFC-BASED CAPE AROUND 100-150 J/KG HELPING TO FUEL WHAT SHOULD BE CONVECTIVE SNOW SHOWERS THURSDAY AFTERNOON. CONFIDENCE IS INCREASING THAT WE WILL SEE ADVISORY-LEVEL SNOW ACCUMULATIONS ACROSS THE NC MOUNTAIN ZONES NEAR THE TN BORDER. THE BETTER SNOW PRODUCTION SHOULD TAPER OFF AROUND DAYBREAK FRIDAY. MEANWHILE...OUTSIDE THE MTNS...IT SHOULD BE DRY AS IT DOES NOT APPEAR THAT SHOWERS WILL BE ABLE TO BREAK CONTAINMENT WITHOUT ANY UPPER SUPPORT. THE MAIN CONCERN HERE WILL BE THE POTENTIAL FOR STRONG WIND GUSTS ON THURSDAY AS COLD ADVECTION ALOFT RESULTS IN A DEEP BOUNDARY LAYER WITH POTENTIAL TO TAP INTO SOME 40KT WIND UP AROUND 750-800 MB. EXPECT A WINDY DAY OUTSIDE THE MTNS...WITH TEMPS BELOW NORMAL. WILL NOT ISSUE A WIND ADVISORY WITH THIS PACKAGE OWING TO ONGOING THREATS TODAY. THE NW FLOW MOISTURE PULLS OUT ON FRIDAY SO WE SHOULD SEE AN END TO SNOW SHOWERS ON THE TN BORDER. TEMPS WILL AGAIN BE 5-10 DEGREES BELOW NORMAL. THE FINAL SHORT WAVE DROPS DOWN THRU THE BOTTOM OF THE UPPER TROF ON FRIDAY NIGHT. THE MODELS DISAGREE IF THERE WILL BE ANY SURFACE REFLECTION OF THIS...AS THEY DO NOT GENERATE ANY PRECIP... EVEN WITH A FINAL SURGE OF LOW LEVEL MOISTURE IN THE NW UPSLOPE REGION. A DRY FCST WAS INHERITED...SO A CHANGE WILL NOT BE MADE AT THIS POINT. QUIET WEATHER WILL CONTINUE EAST OF THE MTNS. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 230 AM WEDNESDAY...THE WEEKEND LOOKS LIKE IT WILL BE DRY WITH A WARMING TREND. THE UPPER PATTERN SHOULD BECOME MORE PROGRESSIVE WITH THE UPPER TROF FINALLY SLIPPING EAST OUT OVER THE ATLANTIC AND A DEAMPLIFYING UPPER RIDGE BUILDING IN THROUGH SUNDAY. THIS WILL SUPPORT HIGH PRESSURE AT THE SURFACE ACROSS MOST OF THE SOUTHEAST AND CAROLINAS THRU SUNDAY EVENING. TEMPS SHOULD MAKE IT BACK ABOVE NORMAL ON SUNDAY AFTERNOON. A SURFACE FRONT WILL APPROACH FROM THE WEST LATE IN THE DAY ON SUNDAY. THE GFS CONTINUES TO HAVE MORE RESPONSE THAN THE ECMWF...BUT EVEN THE GFS DOES NOT BRING PRECIP INTO THE AREA BEFORE MIDNIGHT. WILL PUSH BACK THE PRECIP CHANCE REACHING THE MTNS UNTIL LATER IN THAT PERIOD. WARM ADVECTION AHEAD OF THE FRONT SHOULD KEEP TEMPS ABOVE FREEZING...SO ANY PRECIP THAT REACHES THE MTNS BY DAYBREAK MONDAY SHOULD BE LIQUID. BEYOND THAT...NO OTHER CHANGES WERE MADE. THE FRONT LOOKS LIKE IT WILL FALL APART AS IT CROSSES THE REGION ON MONDAY. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AT KCLT AND ELSEWHERE EAST OF THE MTNS...VERY STRONG AND GUSTY WINDS ARE THE MAIN CONCERN THRU THIS EVENING...AS DEEP MIXING AND STRONG LLVL WIND FIELD IS COMBINING TO PRODUCE FREQUENT GUSTS IN THE 30-40 KT RANGE...AND OCCASIONALLY 40-48 KT ACROSS THE UPSTATE. THE LINE OF CONVECTION IS JUST EXITING EAST OF KCLT AT TIME OF 18Z TAF. OTHERWISE...LOOKING AT AREA RADAR AND VISIBLE SATELLITE IMAGERY...THE THREAT FOR ADDITIONAL STORMS HAS WANED. A LOW VFR CUMULUS DECK IS WRAPPING AROUND THE DEEP LOW PRESSURE SYSTEM TO OUR NORTH...WITH SOME OF THAT CLOUD COVER SNEAKING AROUND THE MTNS FROM THE SW INTO THE WESTERN UPSTATE. THIS THE CLOUDS WILL FILL BACK IN...BUT GENERALLY 4000 TO 6000 FT. GUIDANCE WANTS TO LOWER CIGS TO MVFR AT KAND FOR EARLY EVENING...BUT WILL GO WITH 3500 FT FOR NOW. THE LOW CLOUDS SHOULD CLEAR OUT BY DAYBREAK...AS FLOW VEERS TO MORE WESTERLY TO WEST-NORTHWESTERLY AND DOWNSLOPING INCREASES. GUSTY WESTERLY TO SOUTHWESTERLY WINDS WILL CONTINUE THRU THURSDAY. AT KAVL...WITH THE WINDS BEING MORE ACROSS THE VALLEY...GUSTS ARE NOT AS STRONG AS IN THE PIEDMONT...BUT STILL GUSTY OUT OF THE SW. WINDS WILL SHIFT TO NW LATER THIS EVENING...AND SOME LOW VFR OR MVFR CLOUDS SHOULD WORK UP THE VALLEY FORM THE N. THERE IS A CHANCE OF SNOW SHOWERS EARLY THURSDAY...SO WILL GO WITH PROB30. OUTLOOK...GUSTY WEST WINDS ARE EXPECTED TO LINGER ACROSS THE AREA ON THURSDAY WITH A PERIOD OF NW FLOW SNOW ALONG THE TN/NC BORDER. DRYING EXPECTED TOWARD THE WEEKEND. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 93% HIGH 98% HIGH 100% HIGH 100% KGSP HIGH 97% HIGH 98% HIGH 100% HIGH 100% KAVL MED 74% MED 67% HIGH 100% HIGH 100% KHKY HIGH 89% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 95% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 85% HIGH 95% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: WWW.WEATHER.GOV/GSP/AVIATION && .GSP WATCHES/WARNINGS/ADVISORIES... GA...HIGH WIND WARNING UNTIL 7 PM EST THIS EVENING FOR GAZ010-017- 018-026-028-029. WIND ADVISORY FROM 7 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR GAZ010-017-018-026-028-029. NC...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NCZ033-035- 048>050-053-065-501>510. HIGH WIND WARNING UNTIL 7 PM EST THIS EVENING FOR NCZ036-037- 051-052-056>059-062>064-068>072-082. WIND ADVISORY FROM 7 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR NCZ036-037-051-052-056>059-062>064-068>072-082. WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 7 AM EST FRIDAY FOR NCZ033-048>053-058-059-062. FLASH FLOOD WATCH UNTIL 6 PM EST THIS EVENING FOR NCZ035>037- 056-057-069>072-082. SC...HIGH WIND WARNING UNTIL 7 PM EST THIS EVENING FOR SCZ001>014- 019. WIND ADVISORY FROM 7 PM THIS EVENING TO MIDNIGHT EST TONIGHT FOR SCZ001>014-019. FLASH FLOOD WATCH UNTIL 6 PM EST THIS EVENING FOR SCZ009-014. && $$ SYNOPSIS...SBK NEAR TERM...ARK/NED SHORT TERM...PM LONG TERM...PM AVIATION...ARK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1013 AM EST WED FEB 24 2016 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL MOVE NORTHEAST ACROSS THE TENNESSEE VALLEY TODAY AND SWING A COLD FRONT OVER THE CAROLINAS AND NORTHEAST GEORGIA. DRY AND SEASONABLE HIGH PRESSURE WILL BUILD IN FROM THE WEST FRIDAY AND REMAIN THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1000 AM...THE WEDGE FRONT CONTINUES TO RETREAT AS EXPECTED...WITH JUST THE NC FOOTHILLS AND PORTIONS OF THE NW PIEDMONT STILL IN THE WEDGE. THE LAPS AND RAP CAPE ANALYSES SHOWING THE UNCOVERED AIR MASS IS BECOMING UNSTABLE...WITH 500-1000 J/KG OF SBCAPE...ACROSS THE UPPER SAVANNAH VALLEY. THIS POCKET OF BEST INSTABILITY IS LINING UP WITH DEVELOPING LINE OF CONVECTION FROM THE NC ESCARPMENT TO AROUND GREENWOOD SC. THIS BROKEN LINE WILL LIKELY INTENSIFY AS IT TRACKS EAST...WITH PLENTY OF SHEAR FOR ROTATING UPDRAFTS AND WIND/HAIL/TORNADO THREAT DEVELOPING. THE LATEST DAY 1 CONVECTIVE OUTLOOK HAS SHIFTED THE SLGT RISK TO THE EAST...NOW JUST BARELY CLIPPING THE EASTERN TIER OF OUR COUNTIES. THIS AREA IS WHERE THE INSTABILITY AND SHEAR WILL LINE UP BEST FOR MORE ROBUST SUPERCELLS. THE RAP 0-1 KM EHI OVER 1 EAST OF I-77 EARLY THIS AFTERNOON. WILL KEEP MENTION OF SEVERE FOR THE I-77 CORRIDOR. TO THE WEST...THERE IS A NON-ZERO SEVERE THREAT...BUT THE BIGGER THREAT LOOKS TO BE WINDS...BOTH IN CONVECTION AND JUST WITH MIXING. THE LATEST NAM AND HIGH RES/NEAR TERM GUIDANCE STILL INDICATING SOLID 30-40 MPH GUSTS ACRS THE ENTIRE CWFA FROM MIDDAY THRU THE EVENING...WITH AN OCCASIONAL HIGHER GUST POSSIBLE. THE WIND HEADLINES LOOK ON TRACK. THE ENVIRONMENT ALONG AND AHEAD OF THE ADVANCING COLD FRONT APPEARS VERY INTERESTING AFTER MID MORNING. NAM FORECAST SOUNDINGS MAINTAIN A VERY LOW LFC...GENERALLY 2 KFT. HELICITY BETWEEN 0-1 KM IS FORECAST TO RANGE FROM 250-300 M2/S2 ACROSS THE PIEDMONT AND EASTERN FOOTHILLS. INSTABILITY IS MUCH MORE UNCERTAIN...HOWEVER...IT SHOULD EASILY INCREASE ACROSS THE NC PIEDMONT AND NE UPSTATE OF SC IN THE WAKE OF THE DEPARTING WEDGE BOUNDARY...REACHING 600-900 J/KG. IN FACT...MID DAY VALUES OF EHI OVER KCLT NEAR 2.5 ACCORDING TO THE NAM. IN ADDITION...GFS360 INDICATES THAT A BELT OF H5 Q-VECTOR CONVERGENCE WILL SWEEP ACROSS THE I-77 CORRIDOR DURING THE LATE MORNING TO MID AFTER HOURS. CAMS SIMULATED REFLECTIVITY APPEAR VERY REALISTIC GIVEN THE EXPECTED ENVIRONMENT...SHOWING LIMITED DEVELOPMENT ACROSS THE MTNS AND FOOTHILLS. HOWEVER...BY EARLY AFTERNOON...A NORTH-SOUTH LINE OF TSRA DEVELOPS ALONG THE COLD FRONT OVER THE I-77 CORRIDOR. THIS WILL BE THE FEATURE TO WATCH...POSSIBLY RESULTING IN DAMAGING WINDS...HAIL...AND A ISOLATED TORNADO. WE WILL CONTINUE TO HIGHLIGHT SVR TSRA IN THE HWO AND THE FORECAST. THE SECOND HAZARD IS EXCESSIVE RAINFALL. SO FAR...IT APPEARS THAT THE SQUALL LINE ACROSS THE DEEP SOUTH IS BLOCKING THE DEEPEST MOISTURE FROM REACHING THE FORECAST AREA. HOWEVER...CONVECTIVE DOWNPOURS AND PRESENT HIGH STREAM FLOWS WOULD YIELD EASY CONDITIONS FOR FLASH FLOODING TO DEVELOP...NO CHANGES TO THE FLASH FLOOD WATCH. THE SATURATED GROUND AND GUSTY WINDS WILL LIKELY YIELD DOWNED TREES TODAY AND THIS EVENING...I WILL KEEP WIND HEADLINES THROUGH THIS MORNING. EXTENDING WIND ADVISORY ACROSS THE MTNS TO MATCH FOOTHILL AND PIEDMONT ADVISORY THROUGH MIDNIGHT. TONIGHT...WRAP-AROUND MOISTURE...CAA...AND GUSTY NW WINDS WILL SUPPORT UPSLOPE PRECIPITATION ACROSS THE NC MTNS. GIVEN THE TIMING THE CAA...PRECIP WILL CHANGE OVER THE -SN AROUND MIDNIGHT. RELATIVELY DEEP MOISTURE AND STRONG FLOW WILL SUPPORT ACCUMULATING SHSN ACROSS THE MTNS THROUGH THE LATE NIGHT HOURS. IT IS POSSIBLE MANY AREAS ALONG THE TN LINE WILL SEE AROUND TWO INCHES ON THE GROUND BY SUNRISE THURSDAY. ACCUMULATING SNOWFALL WILL CONTINUE INTO THURSDAY. WE WILL POST A WINTER WEATHER ADVISORY STARTING AT MIDNIGHT. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 130 AM EST WEDNESDAY...FAIRLY STRAIGHT-FORWARD LOOKING SITUATION FOR THE REST OF THE WORK WEEK...DOMINATED MAINLY BY AN UPPER TROF LEFT BEHIND IN THE WAKE OF THE DEPARTING STORM SYSTEM. THE MAIN ISSUE WILL BE PRECIP PRODUCTION ACROSS THE NC MOUNTAINS... MAINLY NEAR THE TN BORDER...AT LEAST THROUGH THURSDAY AND THURSDAY NIGHT. THE OPERATIONAL MODELS AGREE THAT MOISTURE WILL BE RELATIVELY DEEP THROUGH AT LEAST THURSDAY EVENING...WHILE THICKNESS/FCST SOUNDINGS SUPPORT PRECIP FALLING ALMOST ENTIRELY AS SNOW EVEN ON THURSDAY AFTERNOON WHEN TEMPS MAY CLIMB CLOSE TO 40 DEGREES IN SOME VALLEY LOCATIONS. THERE ARE SOME CONFLICTING SIGNALS. ON THE ONE HAND...THE FLOW IS MORE WESTERLY THROUGH THE DAYTIME HOURS ON THURSDAY...ALTHOUGH IT DOES VEER AROUND TO A MORE NW DIRECTION AROUND 00Z FRIDAY. ON THE OTHER HAND...WHAT THE SITUATION LACKS IN MECHANICAL FORCING WILL BE MADE UP BY SFC-BASED CAPE AROUND 100-150 J/KG HELPING TO FUEL WHAT SHOULD BE CONVECTIVE SNOW SHOWERS THURSDAY AFTERNOON. CONFIDENCE IS INCREASING THAT WE WILL SEE ADVISORY-LEVEL SNOW ACCUMULATIONS ACROSS THE NC MOUNTAIN ZONES NEAR THE TN BORDER. THE BETTER SNOW PRODUCTION SHOULD TAPER OFF AROUND DAYBREAK FRIDAY. MEANWHILE...OUTSIDE THE MTNS...IT SHOULD BE DRY AS IT DOES NOT APPEAR THAT SHOWERS WILL BE ABLE TO BREAK CONTAINMENT WITHOUT ANY UPPER SUPPORT. THE MAIN CONCERN HERE WILL BE THE POTENTIAL FOR STRONG WIND GUSTS ON THURSDAY AS COLD ADVECTION ALOFT RESULTS IN A DEEP BOUNDARY LAYER WITH POTENTIAL TO TAP INTO SOME 40KT WIND UP AROUND 750-800 MB. EXPECT A WINDY DAY OUTSIDE THE MTNS...WITH TEMPS BELOW NORMAL. WILL NOT ISSUE A WIND ADVISORY WITH THIS PACKAGE OWING TO ONGOING THREATS TODAY. THE NW FLOW MOISTURE PULLS OUT ON FRIDAY SO WE SHOULD SEE AN END TO SNOW SHOWERS ON THE TN BORDER. TEMPS WILL AGAIN BE 5-10 DEGREES BELOW NORMAL. THE FINAL SHORT WAVE DROPS DOWN THRU THE BOTTOM OF THE UPPER TROF ON FRIDAY NIGHT. THE MODELS DISAGREE IF THERE WILL BE ANY SURFACE REFLECTION OF THIS...AS THEY DO NOT GENERATE ANY PRECIP... EVEN WITH A FINAL SURGE OF LOW LEVEL MOISTURE IN THE NW UPSLOPE REGION. A DRY FCST WAS INHERITED...SO A CHANGE WILL NOT BE MADE AT THIS POINT. QUIET WEATHER WILL CONTINUE EAST OF THE MTNS. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 230 AM WEDNESDAY...THE WEEKEND LOOKS LIKE IT WILL BE DRY WITH A WARMING TREND. THE UPPER PATTERN SHOULD BECOME MORE PROGRESSIVE WITH THE UPPER TROF FINALLY SLIPPING EAST OUT OVER THE ATLANTIC AND A DEAMPLIFYING UPPER RIDGE BUILDING IN THROUGH SUNDAY. THIS WILL SUPPORT HIGH PRESSURE AT THE SURFACE ACROSS MOST OF THE SOUTHEAST AND CAROLINAS THRU SUNDAY EVENING. TEMPS SHOULD MAKE IT BACK ABOVE NORMAL ON SUNDAY AFTERNOON. A SURFACE FRONT WILL APPROACH FROM THE WEST LATE IN THE DAY ON SUNDAY. THE GFS CONTINUES TO HAVE MORE RESPONSE THAN THE ECMWF...BUT EVEN THE GFS DOES NOT BRING PRECIP INTO THE AREA BEFORE MIDNIGHT. WILL PUSH BACK THE PRECIP CHANCE REACHING THE MTNS UNTIL LATER IN THAT PERIOD. WARM ADVECTION AHEAD OF THE FRONT SHOULD KEEP TEMPS ABOVE FREEZING...SO ANY PRECIP THAT REACHES THE MTNS BY DAYBREAK MONDAY SHOULD BE LIQUID. BEYOND THAT...NO OTHER CHANGES WERE MADE. THE FRONT LOOKS LIKE IT WILL FALL APART AS IT CROSSES THE REGION ON MONDAY. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... AT KCLT AND ELSEWHERE EAST OF THE MTNS...COLD AIR DAMMING WILL CONTINUE ACROSS THE FOOTHILLS AND PIEDMONT THROUGH MID MORNING. UNTIL THE WEDGE ERODES...CLOUD BASES WILL RANGE IN THE VLIFR TO LIFR LEVELS AND IFR VIS AND STEADY ENE WINDS. IN ADDITION...ROUNDS OF MODERATE SHRA WILL PASS OVER THE REGION WITH STRENGTHENING LLVL LIFT. AS THE RETREATING WEDGE BOUNDARY APPROACHES THIS MORNING...LLWS WILL LIKELY CONTINUE ACROSS THE FOOTHILLS AND PIEDMONT. HOWEVER...AS THE WARM SECTOR BUILDS ACROSS THE REGION MID TO LATE MORNING...WINDS WILL VEER FROM THE SOUTH WITH REGULAR GUSTS IN THE MID TO UPPER 20S...ENDING LLWS. SFC BASED INSTABILITY WILL SWEEP ACROSS THE REGION AHEAD OF A COLD FRONT...SUPPORTING A MENTION OF LATE MORNING TO MID AFTERNOON TSRA. BY THIS LATE AFTERNOON...TSRA WILL END AND SKY WILL MIX TO VFR. GUSTY SW WINDS WILL CONTINUE THROUGH THE REST OF THE TAF PERIOD. AT KAVL...OVERALL CONDITIONS WILL REMAIN SIMILAR TO FOOTHILL AND PIEDMONT TERMINALS. HOWEVER...WINDS WILL REMAIN FROM THE SOUTH FOR MUCH OF TODAY...WITH GUSTS IN THE MID TO UPPER 20S DEVELOPING DURING THE AFTERNOON. MVFR CEILINGS WILL LIKELY LINGER AS NW WINDS DEVELOP AND SUPPORTS UPSLOPE CLOUD COVER. OUTLOOK...GUSTY WEST WINDS ARE EXPECTED TO LINGER ACROSS THE AREA ON THURSDAY WITH A PERIOD OF NW FLOW SNOW ALONG THE TN/NC BORDER. DRYING EXPECTED TOWARD THE WEEKEND. CONFIDENCE TABLE... 15-21Z 21-03Z 03-09Z 09-12Z KCLT MED 72% HIGH 100% HIGH 100% HIGH 100% KGSP MED 79% HIGH 98% HIGH 100% HIGH 100% KAVL MED 64% MED 75% LOW 58% MED 65% KHKY MED 72% HIGH 98% HIGH 100% HIGH 100% KGMU MED 72% HIGH 95% HIGH 100% HIGH 100% KAND MED 76% HIGH 80% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: WWW.WEATHER.GOV/GSP/AVIATION && .GSP WATCHES/WARNINGS/ADVISORIES... GA...FLASH FLOOD WATCH UNTIL 6 PM EST THIS EVENING FOR GAZ010-017- 018-026-028-029. WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR GAZ010-017-018- 026-028-029. NC...FLASH FLOOD WATCH UNTIL 6 PM EST THIS EVENING FOR NCZ033- 035>037-048>053-056>059-062>065-068>072-082-501>510. WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NCZ033-035>037- 048>053-056>059-062>065-068>072-082-501>510. HIGH WIND WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NCZ051-052- 058-059-062>064. WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 7 AM EST FRIDAY FOR NCZ033-048>053-058-059-062. SC...FLASH FLOOD WATCH UNTIL 6 PM EST THIS EVENING FOR SCZ001>014- 019. WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR SCZ001>014-019. && $$ SYNOPSIS...SBK NEAR TERM...ARK/NED SHORT TERM...PM LONG TERM...PM AVIATION...NED
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
446 AM EST WED FEB 24 2016 .SHORT TERM (TODAY THROUGH FRIDAY)... A STRONG SURFACE LOW PRESSURE CENTER IS CURRENTLY LOCATED ACROSS MIDDLE TENNESSEE MOVING OFF TO THE NORTHEAST. A WARM FRONT EXTENDS ACROSS NORTH ALABAMA INTO CENTRAL GEORGIA FROM THIS LOWS WITH A COLD STRETCHING SOUTHWARD ALONG THE AL/MS LINE AT PRESENT TIME. THE WINDS ACROSS THE SOUTHERN VALLEY REMAIN FROM THE SOUTHEAST WITH THE WARM FRONT STILL TO THE SOUTH. GRADIENT WINDS WITH THE SYSTEM ARE FAIRLY STRONG AND HAVE SEEN GUST AT KCHA ALREADY UP TO 32 KTS. CURRENT WATER VAPOR IMAGERY AND RAP UPPER AIR ANALYSIS INDICATES A DEEP CLOSED LOW MOVING ACROSS THE SOUTHERN MISSISSIPPI RIVER VALLEY. IN ADDITION...WATER VAPOR IMAGERY REVEALS SOME DRY AIR WRAPPING INTO THE SYSTEM ACROSS MISSISSIPPI AND ALABAMA. THE LOW LEVEL JET IS ALSO IMPRESSIVE ACROSS THE REGION WITH WINDS AT 850 MB IN THE 50 TO 60 KT RANGE. EVEN THOUGH THE CURRENT FLOW IS PERPENDICULAR TO THE MOUNTAINS...HAVE ONLY SEEN A WIND GUST READING OF UP TO 40 KTS AT CAMP CREEK...WINDS THERE WILL CONTINUE TO PICK UP DURING THE EARLY MORNING HOURS. FOR EARLY THIS MORNING...MODELS DIFFER ON WHETHER THE WARM FRONT MOVES INTO THE SOUTHERN VALLEY BEFORE THE LOW MOVES TO THE NORTHEAST. FOR NOW...THE SPC MAINTAINS A MARGINAL RISK FOR SEVERE WEATHER ACROSS THE SOUTHERN VALLEY AND SOUTHERN APPALACHIANS. MOST MODELS INDICATE THAT THE 60 DEGREE ISODROSOTHEORM WILL REMAIN TO THE SOUTH OF THE AREA AND THIS WILL LIMIT INSTABILITY ACROSS THE AREA. HI-RES MODELS AND CURRENT RADAR TRENDS INDICATE THAT THE BEST THREAT FOR AN ISOLATED DAMAGING WIND GUST WILL COME OUT OF THE AREA OF SHOWERS AND STORMS MOVING NORTHEAST ACROSS NORTHERN ALABAMA. SO FAR...REPORTS AND LIGHTNING ACTIVITY WITH THIS LINE OF SHOWERS AND STORMS HAS BEEN LIMITED. THEREFORE...THE THREAT FOR DAMAGING WINDS REMAINS MARGINAL AT BEST. PW VALUES WITH THIS SYSTEM HAVE BEEN NEAR 1.25 INCHES WHICH IS WELL INTO THE 90TH PERCENTILE FOR THIS TIME OF THE YEAR. ESTIMATED STORM TOTAL AMOUNTS RANGE FROM 1-2 INCHES ACROSS THE SOUTHERN PLATEAU AND SOUTHERN VALLEY OVER THE LAST 12-24 HOURS. THEREFORE...HAVE CONTINUED THE FLOOD WATCH IN THESE COUNTIES. AS MENTIONED EARLIER...THERE IS THE DRY SLOT MOVING IN LATER THIS MORNING AND MAY BE ABLE TO CANCEL THE FLOOD WATCH LATER ON THE DAY SHIFT. THE MOUNTAIN WAVE EVENT HAS NOT BEEN OVERLY IMPRESSIVE YET AND WENT AHEAD AND CHANGED THE EXPIRATION TIME TO 18Z. BY THIS TIME...THE LOW LEVEL WIND FLOW SHOULD BE OUT OF THE SOUTHWEST AND THE THREAT FOR MOUNTAIN WAVES WILL HAVE ENDED. HOWEVER...DID EXTEND THE WIND ADVISORY THROUGH 06Z WITH STRONG GRADIENT WINDS CONTINUING BEHIND THE SYSTEM. DECREASED POPS SLIGHTLY LATE THIS MORNING AND INTO THE AFTERNOON WITH THE DRY SLOT MOVING INTO THE AREA. IN FACT...THERE COULD BE SOME SUNSHINE AT TIMES. THE DYNAMIC SYSTEM WILL WRAP COLD AIR IN BEHIND IT TONIGHT AND INTO THURSDAY. SCATTERED RAIN SHOWERS WILL TRANSITION TO SNOW DURING THE OVERNIGHT HOURS AS COLD AIR MOVES IN WITH 850 MB TEMPERATURES DROPPING INTO THE -10 TO -6 DEGREES CELSIUS RANGE WITH STRONG COLD AIR ADVECTION BEHIND THE DEPARTING SYSTEM. OROGRAPHIC LIFT ALONG THE APPALACHIANS WILL BE ENHANCED BY NORTHWESTERLY FLOW IN THE LOW LEVELS. LOW LEVEL LAPSE RATES WILL BE STEEP THANKS TO THE IMPRESSIVE COLD AIR AT 850 MB. THIS WILL CREATE SCATTERED SNOW SHOWERS ACROSS MOST OF THE AREA TONIGHT THROUGH THURSDAY NIGHT. HIGHEST TOTALS WILL BE ACROSS THE HIGHER ELEVATIONS ALONG THE TN/NC LINE...THE NORTHERN PLATEAU AND SW VIRGINIA. WENT AHEAD AND ISSUED A WINTER WEATHER ADVISORY FOR THESE AREAS WITH 1-2 INCHES OF SNOW EXPECTED FOR MOST OF THESE AREAS WITH UP TO 5 INCHES POSSIBLE ALONG THE TN/NC LINE. PW VALUES REMAIN LOW AROUND A QUARTER OF AN INCH BUT CONTINUED SHORTWAVE TROUGHS MOVE THROUGH THE AREA TONIGHT THROUGH FRIDAY MORNING WILL ENHANCE PRECIP. DEVELOPMENT. A FEW FACTORS WILL LIMIT ACCUMULATIONS OUTSIDE OF THE ADVISORY AREA...THE MAIN ONE BEING THAT TEMPERATURES WILL BE ABOVE FREEZING DURING THE SNOWFALL. EXPECT ACCUMULATION OUTSIDE OF THE ADVISORY WILL RANGE FROM JUST UNDER AN INCH IN THE TRI-CITIES AREA TO A DUSTING TO HALF AN INCH FOR THE KNOXVILLE AREA. .LONG TERM (FRIDAY NIGHT THROUGH WEDNESDAY)... FAVORABLE WEATHER FOR US AS WE HEAD INTO THE WEEKEND WITH MOSTLY CLEAR SKIES AND TEMPERATURES TOPPING OUT IN THE 50`S TO 60`S FOR MUCH OF THE AREA. QUASI-ZONAL FLOW WILL HELP KEEP THINGS QUIET UNTIL THE EARLY PART OF NEXT WEEK WHEN A LOW MOVES ACROSS THE GREAT LAKES AND THE ASSOCIATED COLD FRONT SWEEPS THROUGH THE AREA. MODELS ARE STILL NOT IN GREAT AGREEMENT WITH THE AMOUNT OF MOISTURE THAT WILL BE ASSOCIATED WITH THIS SYSTEM, SO CONFIDENCE ON RAINFALL CHANCES IS RELATIVELY LOW AT THIS TIME. AT THIS POINT IF THERE IS ENOUGH MOISTURE WITH THE FRONT MOST OF THE AREA LIKELY SEE ALL RAIN AS IT MOVES THROUGH...THERE COULD BE A FEW OF THE HIGHEST MOUNTAIN TOPS THAT GET A BIT OF SNOW MIXED IN DURING THE OVERNIGHT MONDAY. CURRENT FORECAST HAS HIGH TEMPERATURES EARLY NEXT WEEK A FEW DEGREES ABOVE NORMAL FOR MOST OF THE AREA. && .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 56 37 43 29 / 80 60 20 10 KNOXVILLE MCGHEE TYSON AIRPORT, TN 59 36 40 28 / 80 70 20 30 OAK RIDGE, TN 57 35 40 28 / 90 70 20 30 TRI CITIES AIRPORT, TN 61 32 36 25 / 80 70 70 70 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...HIGH WIND WARNING UNTIL 1 PM EST THIS AFTERNOON FOR CHEROKEE- CLAY. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST FRIDAY FOR CHEROKEE-CLAY. WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM EST THURSDAY FOR CHEROKEE-CLAY. FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR CHEROKEE-CLAY. TN...HIGH WIND WARNING UNTIL 1 PM EST THIS AFTERNOON FOR BLOUNT SMOKY MOUNTAINS-COCKE SMOKY MOUNTAINS-EAST POLK-JOHNSON-MCMINN-NW BLOUNT-NORTH SEVIER-NORTHWEST CARTER-NORTHWEST COCKE- NORTHWEST GREENE-NORTHWEST MONROE-SEVIER SMOKY MOUNTAINS- SOUTHEAST CARTER-SOUTHEAST GREENE-SOUTHEAST MONROE-UNICOI- WASHINGTON TN. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST FRIDAY FOR BLOUNT SMOKY MOUNTAINS-COCKE SMOKY MOUNTAINS- JOHNSON-NORTHWEST CARTER-SEVIER SMOKY MOUNTAINS-SOUTHEAST CARTER-SOUTHEAST GREENE-SOUTHEAST MONROE-UNICOI. WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM EST THURSDAY FOR BLOUNT SMOKY MOUNTAINS-COCKE SMOKY MOUNTAINS-EAST POLK- JOHNSON-MCMINN-NW BLOUNT-NORTH SEVIER-NORTHWEST CARTER- NORTHWEST COCKE-NORTHWEST GREENE-NORTHWEST MONROE-SEVIER SMOKY MOUNTAINS-SOUTHEAST CARTER-SOUTHEAST GREENE-SOUTHEAST MONROE-UNICOI-WASHINGTON TN. FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR BRADLEY-EAST POLK- HAMILTON-MARION-WEST POLK. WIND ADVISORY UNTIL 1 AM EST /MIDNIGHT CST/ THURSDAY FOR ANDERSON-BLEDSOE-BRADLEY-CAMPBELL-CLAIBORNE-GRAINGER- HAMBLEN-HAMILTON-HANCOCK-HAWKINS-JEFFERSON-KNOX-LOUDON- MARION-MEIGS-MORGAN-RHEA-ROANE-SCOTT TN-SEQUATCHIE-SULLIVAN- UNION-WEST POLK. WINTER WEATHER ADVISORY FROM 1 AM TO 7 PM EST THURSDAY FOR CAMPBELL-CLAIBORNE-MORGAN-SCOTT TN. VA...HIGH WIND WARNING UNTIL 1 PM EST THIS AFTERNOON FOR RUSSELL- WASHINGTON. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST FRIDAY FOR LEE-RUSSELL-SCOTT-WASHINGTON-WISE. WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM EST THURSDAY FOR RUSSELL-WASHINGTON. WIND ADVISORY UNTIL 1 AM EST THURSDAY FOR LEE-SCOTT-WISE. && $$ MA/ABM
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1152 PM CST TUE FEB 23 2016 .UPDATE... FOR 06Z AVIATION DISCUSSION. && .DISCUSSION... MS AT THIS TIME. THE STRENGTH OF THE SFC LOW IS NOTICEABLY STRONGER THAN THE MODEL PROGS. THOSE MODEL PROGS STILL BRING A GOOD ONE HALF TO ONE INCH OF RAINFALL ACROSS MUCH OF THE MID STATE BETWEEN 6 PM AND MIDNIGHT TONIGHT. CURRENT MOSAIC SHOWS A LARGE AREA OF HEAVIER RAINFALL ACROSS MUCH OF WEST CENTRAL AL...WITH THIS PRECIPITATION MOVING NORTHWARD. HRRR IS ALSO IN LINE WITH HEAVIER RAINFALL MOVING OUR WAY. ON THE WATER VAP IMAGERY...YOU CAN CLEARLY SEE THE ASSOCIATED UPPER LEVEL LOW SPINNING ACROSS EASTERN TX. PVA IN ADVANCE OF THIS FEATURE IS A LITTLE UNDERDONE AND THEREBY...YOU HAVE A STRONGER SFC LOW. UPPER DIVERGENCE IS RATHER IMPRESSIVE AND RESIDES ABOVE STRONG LOWER LEVEL AND UP TO 850 MB FORCING. 90+ MRH AREA IS RATHER EXTENSIVE AND SHOULD COVER THE MID STATE THROUGH ABOUT 9Z. LOOKING AT FFG LEVELS...THE DATA WAS ISSUED EARLIER TODAY. IT APPEARS THAT 1 TO 1 1/2 INCHES IN 1 HOUR IS THE THRESHOLD. FOR 6 HRS...2 TO 2 1/2 INCHES IS NEEDED. BEST INSTABILITY LEVELS WILL REACH INTO OUR SOUTHWESTERN COUNTIES BY 10 PM. TSTM FORMATION WILL CERTAINLY LEAD TO AN ENHANCED CHANCE OF AT LEAST SOME MINOR FLOODING PROBLEMS. OTW...NO FLOOD WATCH IS NEEDED GOING FORWARD. EXPECTATIONS ARE FOR AROUND 1 INCH TOTAL THROUGH MIDNIGHT...UP TO 1 1/2 INCHES SOUTHWESTERN AREAS. NO CHANGES TO THE FCST FOR NOW BUT WILL BE REISSUING THE SPS BY 10 PM WHEN IT EXPIRES. FOR NOW...NO CHANGES EXPECTED TO THE SPS WITH THAT UPCOMING ISSUANCE. && .AVIATION... 06Z TAF DISCUSSION. ACTIVE WX PATTERN CONTINUES TO BE IN STORE AS QUASI STACKED SFC/UPPER LEVEL LOWS MOVE FROM N MS NEWD INTO ERN PORTIONS OF THE SRN OHIO RIVER VALLEY BY 25/06Z. BEST PROXIMITY OF SFC/UPPER LEVEL LOWS TO MID STATE LOOK TO BE IN THE 24/06Z-24/09Z TIME FRAME. SOME MODERATE RAINFALL MAY BE POSSIBLE...ESPECIALLY NEAR CKV...DURING THIS TIME FRAME. STILL CONTINUE TO EXPECT SEVERAL AMENDMENTS THRU 25/06Z PER ACTUAL CEILING AND VSBY FLUCTUATIONS. OVERALL...WILL CONTINUE TO GO WITH MVFR CEILINGS/VSBYS CKV/BNA AND LIFR CEILINGS CKV/IFR VSBYS THRU 25/06Z. AS FRONTAL SYSTEM CONTINUES TO MOVE CLOSER TO...ACROSS... AND EXITS THE MID STATE REGION...SFC PRESSURE GRADIENT SHOULD SUPPORT GUSTS TO 20 TO 25 KTS...WITH NE/E WINDS SHIFTING TO W/NW AS SYSTEM MOVES NEWD INTO ERN OHIO VALLEY REGION BY 25/06Z. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM/AVIATION........31 LONG TERM..................21
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1034 PM CST TUE FEB 23 2016 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .UPDATE... ISSUED AT 808 PM CST TUE FEB 23 2016 NOT A BIG UPDATE TONIGHT. AS PER GOING FORECAST...SNOW DIMINISHING WHILE MOVING TOWARD EASTERN WISCONSIN. CAMS ACROSS CENTRAL WISCONSIN SHOW WET ROADS. ACROSS NORTH CENTRAL WISCONSIN...RADARS SHOWING A TAD CONVECTIVE LOOK AS THE MID LEVEL TROUGH WORKS INTO THE AREA. SOME MID LEVEL LAPSE RATES MAY BE RESPONSIBLE FOR THESE CONVECTIVE ELEMENTS...WITH SLIGHT 850 WAA INTO COLDER H7 TEMPS OF -14 C. ISSUED A SPS FOR NC WI FOR AN INCH OR TWO THIS EVENING. AS FAR AS FOG POTENTIAL TONIGHT...A FEW HOLES BRIEFLY OPEN UP BUT SAT TRENDS DO NOT SHOW SIG CLEARING COMPARED TO THE PREVIOUS NIGHT. STILL LIGHT WINDS AND MOIST BOUNDARY PRODUCING SOME 3-5 MILE MVFR VSBYS EARLY THIS EVENING. && .SHORT TERM...TONIGHT AND WEDNESDAY ISSUED AT 250 PM CST TUE FEB 23 2016 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SEVERAL SHORTWAVES MOVING ACROSS MINNESOTA. A WEAK COLD FRONT IS EXTENDING SOUTH FROM A LOW PRESSURE SYSTEM LOCATED OVER NORTHERN MINNESOTA. LIGHT SNOW SHOWERS AND FLURRIES ARE MOVING EAST OVER THE WESTERN HALF OF WISCONSIN...AND WILL CONTINUE TO SLIDE INTO CENTRAL AND NORTH-CENTRAL WI OVER THE REST OF THE AFTERNOON. WHILE THIS IS OCCURRING...A SOUTHERN STREAM LOW PRESSURE IS ORGANIZING OVER THE GULF COAST. FORECAST CONCERNS INCLUDE SNOW TRENDS THROUGH TONIGHT AND WIND GUSTS ON WEDNESDAY AS THE SOUTHERN STREAM LOW MOVES NORTH. TONIGHT...SHORTWAVE TROUGHS MOVING OVER THE NORTHERN MISSISSIPPI VALLEY WILL BECOME MORE SHEARED AS THEY MOVE INTO THE WESTERN GREAT LAKES. CONSEQUENTLY...THE UPSTREAM COLD FRONT WILL WASH OUT AS IT MOVES INTO NORTH-CENTRAL WISCONSIN LATE THIS EVENING AND OVERNIGHT. UNTIL IT DOES SO...LIGHT SNOW AND FLURRIES WILL REMAIN POSSIBLE MAINLY NORTHWEST OF A WAUTOMA TO IRON MOUNTAIN LINE. NOT ANTICIPATING MUCH ACCUMULATIONS TONIGHT...MAYBE UP TO A HALF INCH. FARTHER EAST...EXPECT AMPLE CLOUD COVER WITH PERHAPS SOME BREAKS IN THE OVERCAST DEVELOPING FROM TIME TO TIME. LOWS IN THE MIDDLE TO UPPER 20S. WEDNESDAY...NORTHEAST FLOW WILL STRENGTHEN AS A STRONG LOW PRESSURE SYSTEM MOVES ACROSS THE OHIO VALLEY. THE PRECIP SHIELD ASSOCIATED WITH THE SYSTEM WILL LIFT NORTHWARD AND COULD CLIP THE SHORELINE AROUND MANITOWOC LATE IN THE AFTERNOON. OTHERWISE...EXPECT PLENTY OF CLOUDS WITH A FEW FLURRIES OVER NORTHERN VILAS CO. NORTHWEST WINDS WILL INCREASE THROUGH THE DAY AND BECOME GUSTY. SOME GUSTS TO 30 OR 35 MPH WILL BE POSSIBLE ALONG THE LAKE SHORE AND THE FOX VALLEY. CONTINUED MILD TEMPS RANGING THROUGH THE 30S. .LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY ISSUED AT 250 PM CST TUE FEB 23 2016 MAIN FCST CONCERN IS THE WEEKEND FORECAST...WITH MUCH ABOVE NORMAL TEMPS POSSIBLE ON SATURDAY...FOLLOWED BY THE POTENTIAL FOR ACCUM SNOW SUNDAY INTO SUNDAY NIGHT. NO SIGNIFICANT CHANGES WERE MADE WITH RESPECT TO THE EFFECTS OF THE LARGE LOW PRESSURE SYSTEM TRACKING THROUGH THE OHIO VALLEY AND EASTERN GREAT LAKES WEDS/WEDS NGT. STILL ONLY EXPECTING A CHANCE OF LIGHT SNOW IN EC WI ON WEDS/WEDS NGT...AND GALES ON LAKE MICHIGAN FROM WEDS AFTERNOON THROUGH THURSDAY. ON THE BACK SIDE OF THE STORM...SOME MINOR LAKE EFFECT SNOWS WILL LIKELY DEVELOP IN VILAS COUNTY THU/THU NGT. PLEASANT WEATHER IS EXPECTED FRIDAY INTO SATURDAY...WITH PARTLY SUNNY SKIES AND MODERATING TEMPERATURES. 925 MB TEMPS WARM TO +2 TO +6 C ON SATURDAY...SUGGESTING THAT MAX TEMPS WILL GET WELL INTO THE 40S IN PARTS OF C/EC WI. WOULD NOT BE SHOCKED TO SEE 50 DEGREES AT THE TYPICAL WARM SPOTS. A COLD FRONT WILL DROP SOUTH THROUGH THE AREA ON SATURDAY NIGHT. A SFC LOW IS EXPECTED TO DEVELOP ALONG THIS FRONT ON SUNDAY AND SUNDAY NIGHT...WITH THE MOST LIKELY TRACK TAKING IT THROUGH NORTHERN ILLINOIS. THIS COULD RESULT IN SEVERAL INCHES OF SNOW IN PARTS OF THE FCST AREA...THOUGH CONFIDENCE IN THE DETAILS IS LOW. THERE SHOULD BE PLENTY OF DYNAMICS...WITH COUPLED UPPER JETS AND SOME MID-LEVEL FRONTOGENETIC FORCING ANTICIPATED. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1034 PM CST TUE FEB 23 2016 LIGHT SNOW OR FLURRIES WILL BE ON DECREASE TONIGHT AS A TROUGH OF LOW PRESSURE WEAKENS AND LIFTS NORTHEAST OF THE AREA. WHILE POCKETS OF VFR CIGS WERE NOTED OVER EASTERN WISCONSIN. ANTICIPATE MORE LIFR/MVFR CIGS AND VSBYS TO DEVELOP TONIGHT AND CONTINUE INTO WEDNESDAY MORNING DUE TO LOW LEVEL MOISTURE AND LIGHT WINDS. SOME IMPROVEMENT WITH CIGS AND VSBYS ON WEDNESDAY AS NORTHEAST WINDS INCREASE DUE TO A STORM SYSTEM PASSING OVER THE OHIO VALLEY. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE.........TDH SHORT TERM.....MPC LONG TERM......KIECKBUSCH AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS ALBANY NY
415 AM EST FRI FEB 26 2016 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE WILL MOVE TO OUR EAST TODAY. LEFTOVER SNOW SHOWERS WILL DIMINISH ACROSS THE REGION LEAVING US WITH A MAINLY DRY DAY WITH INCREASING SUNSHINE...BUT BRISK CONDITIONS. HIGH PRESSURE WILL CREST TO OUR SOUTH LATE TONIGHT BRINGING A MAINLY CLEAR SEASONABLY COLD NIGHT. A SOUTHWEST FLOW WILL ALLOW FOR MODERATING TEMPERATURES FOR THE WEEKEND...ESPECIALLY SUNDAY ALONG WITH MAINLY DRY WEATHER. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 330 AM EST...STILL LOOKING AT SOME UPSLOPE SNOW ACROSS THE HIGHER TERRAIN...ESPECIALLY TO THE EAST OF THE HUDSON VALLEY. HOWEVER RADAR REFLECTIVITY`S HAVE DIMINISHED DURING THE PAST HOUR...IMPLYING SNOWFALL RATES HAVE DIMINISHED. THE LATEST HRRR INDICATED THAT THIS UPSLOPE SNOW SHOULD DIMINISH TO FLURRIES OR ALL END TOGETHER BY 5AM OR SO....AT LEAST OVER EASTERN TERRAIN. THE UPSLOPE/LAKE ENHANCED SNOW SHOWER ACTIVITY WILL LIKELY PERSIST OVER THE ADIRONDACKS THROUGH MUCH OF THE DAY...AND OCCASIONALLY A FEW FRAGMENTED BANDS WILL WORK INTO THE MOHAWK VALLEY AND PERHAPS INTO THE CAPITAL DISTRICT BUT WITH NOTHING MORE THAN FLURRIES EXPECTED. ADDITIONAL SNOW ACCUMULATION FROM HERE ON IN...SHOULD BE AN INCH OR LESS... WITH LITTLE OR NONE IN THE VALLEYS. TEMPERATURES CONTINUE TO SLOWLY SLIDE...RANGING FROM AROUND FREEZING IN THE VALLEYS...WELL DOWN INT0 THE 20S ACROSS THE HIGHER TERRAIN...AND EVEN INTO THE TEENS ACROSS THE ADIRONDACKS. THESE NUMBERS WILL DROP A FEW MORE DEGREES THROUGH DAWN. THE WIND HAS INCREASED AS THE STRONGEST PRESSURE RISES WERE WORKING ACROSS THE REGION ALONG WITH A TIGHT PRESSURE GRADIENT. ALBANY HAD A PEAK WIND GUST TO 44 MPH AND NORTH ADAMS TO 46 MPH. THIS TIGHT PRESSURE RISE WILL SHIFT TO OUR EAST AFTER SUNRISE. WHILE THE STRONGEST WIND GUSTS SHOULD BE TAKING PLACE THROUGH EARLY MORNING...INCREASED MIXING WITH HEATING WILL CERTAINLY KEEP A STRONG BREEZE GOING THROUGHOUT THE DAY. LOOK FOR THE WIND TO AVERAGE 10-20 MPH THROUGHOUT THE DAY...GUSTING TO 30-40 MPH...WITH THE HIGHEST GUSTS OVER THE HIGHER TERRAIN/MOHAWK VALLEY AND CAPITAL REGION. THESE VALUES LOOK TO REMAIN JUST BELOW WIND ADVISORY CRITERIA. H850 TEMPERATURES WILL DIP TO AROUND -15C TODAY. NORMALLY SUCH TEMPERATURES WOULD INSURE BELOW FREEZING HIGHS. HOWEVER GIVEN IT IS LATE FEBRUARY WITH A SUN ANGLE UP TO 37 DEGREES AT ALBANY...AND THE EXCELLENT MIXING HIGH TEMPERATURES SHOULD REACH AROUND FREEZING IN MOST VALLEY LOCATIONS... AND EVEN A LITTLE HIGHER IN THE MID HUDSON VALLEY. HIGHS WILL BE CONSIDERABLY COLDER ACROSS THE HIGHER TERRAIN...GENERALLY LOWER TO MID 20S...EXCEPT 15-20 ACROSS THE ADIRONDACKS. THE WIND WILL PRODUCE WIND CHILL VALUES ABOUT 10-15 COLDER THAN THIS VALUES...VERY COLD BUT NOT THAT CLOSE TO WIND CHILL ADVISORY LEVELS. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... TONIGHT...THE WIND ONLY SLOWLY ABATE SINCE THE HIGH PRESSURE WILL CREST WELL TO OUR SOUTH...KEEPING A PRESSURE GRADIENT OVER THE REGION. THIS SETUP WILL NOT ALLOW FOR OPTIMAL RADIATIONAL COOLING DESPITE A CLEAR TO PARTLY CLOUDY SKY. HOWEVER...LOWS WILL STILL DIP BELOW NORMAL LEVELS... TEENS FROM ALBANY SOUTH...SINGLE NUMBERS WELL NORTH OF THE CAPITAL REGION. SATURDAY...THE AIR MASS WILL BEGIN TO MODERATE. IT STAYS A BIT BREEZY WITH PLENTY OF SUNSHINE...HIGH TEMPERATURES WILL REBOUND TO 35-40 IN THE VALLEYS...MID 20S TO LOWER 30S HIGHER TERRAIN. THESE VALUES WILL BE SPOT ON FOR THE TIME OF YEAR. A WEAK BACKDOOR COLD FRONT WILL DROP INTO OUR NORTHERN AREAS SATURDAY NIGHT. THIS WILL BE THE LEADING OF A VERY COLD AIR MASS THAT EARLIER IN THE WEEK LOOKED TO HAVE BEEN AIMED AT OUR REGION. HOWEVER...THIS AIR MASS WILL PASS WELL NORTH ACROSS SOUTHERN CANADA WITH THE FRONT WASHING OUT WELL NORTH OF I90 SATURDAY NIGHT. THIS FRONT WILL BRING SOME CLOUDS AND PERHAPS A FEW INNOCUOUS SNOW SHOWERS TO NORTHERN AREAS. OVERNIGHT LOWS SATURDAY WILL ACTUALLY BE HIGHER THAN NORMAL DUE TO THE CLOUD AND A SOUTHERLY BREEZE...20S TO AROUND 30. BY SUNDAY...HIGH PRESSURE OFFSHORE WILL STRENGTHEN A SOUTHWESTERLY FLOW ACROSS MOST OF OUR REGION. WITH AT LEAST PARTIAL SUNSHINE AND H850 TEMPERATURES SLATED TO RISE TO AROUND OR A LITTLE ABOVE 0C... LOOK FOR HIGH TEMPERATURES TO REACH 50-55 FROM THE CAPITAL REGION SOUTHWARD...40S EVEN NORTH. THE WIND WILL BE SOUTH 10-15 MPH. && .LONG TERM /MONDAY THROUGH THURSDAY/... THE PERIOD STARTS OUT SUNDAY NIGHT WITH A DEEPENING LOW PRESSURE SYSTEM APPROACHING FROM THE EASTERN GREAT LAKES. THE CYCLONE CENTER IS EXPECTED TO TRACK NORTHEAST ALONG THE ST LAWRENCE VALLEY REGION EARLY MONDAY MORNING...DRAGGING A COLD FRONT ACROSS EAST CENTRAL NEW YORK AND WESTERN NEW ENGLAND. SINCE THERE IS EXPECTED TO BE A PERSISTENT SOUTHWEST BREEZE THROUGH SUNDAY NIGHT...TEMPERATURES SHOULD REMAIN FAIRLY STEADY IN MOST LOCATIONS. DEPENDING ON MOISTURE/STABILITY PROFILES AND THE DEGREE OF MIXING...WINDS COULD END UP BEING QUITE STRONG AND WILL HAVE TO WATCH FOR THIS POTENTIAL. FOR NOW WILL MENTION WIND SPEEDS BELOW ADVISORY CRITERIA. THE SYSTEM DOES LOOK QUITE PROGRESSIVE...WITH A FAST-MOVING OPEN WAVE TROUGH ALOFT. SO MAINLY LIGHT QPF IS EXPECTED...WITH THE BEST CHANCE FOR MEASURABLE RAIN/SNOW SHOWERS ACROSS HIGHER TERRAIN AREAS NORTH OF ALBANY. TEMPS INITIALLY SHOULD BE WARM ENOUGH FOR PLAIN RAIN...BUT WILL THEN TRANSITION TO SNOW SHOWERS ACROSS THE HIGHER TERRAIN MONDAY MORNING. PRECIP LOOK TO TAPER OFF FAIRLY QUICKLY MONDAY ONCE THE COLD FRONT MOVES THROUGH. BREEZY CONDITIONS WILL CONTINUE...ALTHOUGH WINDS WILL SHIFT TO THE NORTHWEST BEHIND THE COLD FRONT. GENERALLY TRANQUIL CONDITIONS EXPECTED MONDAY NIGHT INTO TUESDAY WITH WEAK HIGH PRESSURE MOVING IN. HOWEVER...A WEAK UPPER LEVEL DISTURBANCE COULD RESULT IN A FEW SNOW SHOWERS MAINLY ACROSS THE WESTERN ADIRONDACKS DURING THIS TIME. TEMPS CONTINUE TO BE ABOVE NORMAL WITH NO REAL ARCTIC AIR IN THE VICINITY. MODELS THEN START TO DIVERGE FOR THE TUESDAY NIGHT THROUGH THURSDAY TIME FRAME...WHICH COULD BE RATHER ACTIVE DUE TO A POWERFUL STORM EXPECTED TO EMERGE FROM THE GREAT PLAINS AND TRACK ACROSS THE MIDWEST BY LATE TUESDAY. THE EVENTUAL TRACK LOOK TO BE JUST WEST OF OUR REGION ONCE AGAIN...LIKELY PUTTING US ON THE WARM SIDE OF THE STORM WITH MAINLY RAIN AS PTYPE. HOWEVER...THERE IS QUITE A BIT OF VARIABILITY IN THE STORM TRACK AS THERE IS A CHANCE FOR A MORE SOUTHERLY/EASTERLY TRACK BASED ON THE GFS ENSEMBLE MEAN. THIS COULD MEAN MORE OF A THREAT FOR A WINTRY MIX TO RAIN SCENARIO...ALTHOUGH CONFIDENCE IS LOW AT THIS TIME. TIMING VERY UNCERTAIN AT THIS POINT AS WELL...WITH THE ECMWF MUCH FASTER THAN THE GFS AND ITS ENSEMBLE MEAN. THE ECMWF HAS THE MAIN IMPACTS FORM THE STORM TUESDAY NIGHT INTO EARLY WEDNESDAY...WHILE THE GFS CAMP IS MORE LATE WEDNESDAY THROUGH WEDNESDAY NIGHT. SO BOTTOM LINE IS THERE LOOKS TO BE A GOOD CHANCE FOR MODERATE TO POTENTIALLY HEAVY PRECIP IN A 6-12 HOUR TIME WINDOW...BUT THE DETAILS IN TIMING AND PTYPE ARE FAR FROM CERTAIN AT THIS TIME. STAY TUNED. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... PRETTY STRONG WINDS WERE BUFFETING MAINLY KALB THIS EARLY MORNING WITH GUSTS TO 40KTS NOTED WITH THE 09Z METAR. A STRONG LOW LEVEL JET HAS ENHANCED THESE WINDS BUT SHOULD LIFT OUT AFTER SUNRISE. HOWEVER...INCREASED MIXING WITH KEEP THE GUSTY WINDS GOING THROUGHOUT THE DAY FROM WEST TO NORTHWEST. THEY WILL AVERAGE 10-15KTS WITH GUSTS TO 25KTS AT KPOU AND KGFL AND AROUND 30KTS AT KPSF AND KALB...WITH OCCASIONAL GUSTS TO 40KTS AT TIMES. UPSLOPE SNOWS WERE WEAKENING AT KPSF...BUT COULD NEVERTHELESS PRODUCE OCCASIONAL IFR CONDITIONS DUE TO LOWERED VISIBILITY IN SNOW (2SM) THROUGH 10Z. OTHERWISE...THROUGH 10Z...SNOW SHOWERS COULD BRIEFLY REDUCE VISIBILITY TO MVFR AT THE OTHER TAF SITES (EXCEPT AT KPOU WHERE A VCSH WILL SUFFICE). AFTER SUNRISE...VFR CONDITIONS WILL PREVAIL AS CIGS SHOULD BECOME SCATTERED AROUND 4 KFT AGL. VISIBILITIES WILL BE UNRESTRICTED. THESE WINDS WILL PERSIST INTO THE EVENING PEAK...BEFORE DIMINISHING A LITTLE (BUT NOT COMPLETELY) TONIGHT. OUTLOOK... SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. MONDAY: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA. MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN. WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA. && .HYDROLOGY... NO MORE RAIN IS EXPECTED FOR THE NEXT SEVERAL DAYS. ANY PRECIPITATION THAT FALLS TODAY WOULD BE IN THE FORM OF FLURRIES OR SNOW SHOWERS WITH VIRTUALLY NO EFFECT ON RIVERS AND STREAMS. MOST...IF NOT ALL WATERSHEDS HAVE CRESTED AND WILL SLOWLY RECEDE DURING THE NEXT SEVERAL DAYS. THE NEXT CHANCE OF SIGNIFICANT PRECIPITATION WILL NOT BE UNTIL NEXT WEDNESDAY...IN THE FORM OF RAIN OR MIXED PRECIPITATION. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...HWJIV NEAR TERM...HWJIV SHORT TERM...HWJIV LONG TERM...JPV AVIATION...HWJIV HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
303 AM EST FRI FEB 26 2016 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE AND AN UPSLOPE WIND WILL ALLOW FOR NUMEROUS SNOW SHOWERS MAINLY OVER THE ELEVATED TERRAIN EAST OF THE HUDSON VALLEY OVERNIGHT...BRINGING SOME LIGHT TO LOCALLY MODERATE SNOWFALL ACCUMULATIONS. LIGHT SNOW SHOWERS WILL BE SCATTERED ACROSS THE REMAINDER OF THE REGION WITH LITTLE OR NO ACCUMULATIONS. HIGH PRESSURE WILL BUILD TO OUR SOUTH BRINGING AN END TO MOST OF THE SNOW SHOWERS LATER TODAY. IT WILL BE A PARTLY TO MOSTLY SUNNY BUT BRISK AND CHILLY DAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 115 AM EST...RADARS HAVE DETECTED ENHANCED AREAS OF UPSLOPE SNOW...MAINLY ACROSS THE ELEVATED TERRAIN TO THE EAST OF THE HUDSON VALLEY. SNOWFALL RATES LOOK TO BE AROUND HALF AN INCH PER HOUR AND WE DID HAVE ONE TWITTER REPORT OF MODERATE SNOWFALL IN LENOX MA. THIS UPSLOPE WAS DUE TO THE EFFECTS OF AN UPPER LEVEL DISTURBANCE/SHORT WAVE...COMBINED WITH CYCLONIC FLOW AND ENHANCED MOISTURE OFF LAKE ONTARIO. THE LATEST HRRR MODEL INDICATE THIS ACTIVITY SHOULD DIMINISH BY 400 AM OR SO AS THE UPPER SYSTEM MOVES AWAY...THE FLOW BECOMES MORE ANTICYCLONIC...DRYING THE COLUMN OUT. UNTIL THEN...1-3 INCHES OF SNOW SNOW LOOKS TO ACCUMULATE ALONG THE SPINE OF THE TACONICS...SOUTHERN GREENS...BERKSHIRES AND EVEN INTO THE LITCHFIELD HILLS. OTHER LESS IMPRESSIVE UPSLOPE SNOWS WERE NOTED ACROSS THE ADIRONDACKS WITH AMOUNTS CLOSER TO AN INCH. SCATTERED SNOW SHOWERS WERE DETECTED IN REMAINING AREAS...EVEN MOST VALLEY LOCATIONS...WITH A DUSTING POSSIBLE. ALL OF THIS ACTIVITY SHOULD DIMINISH BEFORE DAYBREAK. A NORTHWEST WIND 10-15 MPH...GUSTING TO OVER 30 MPH (ESPECIALLY IN THE WIND PRONE AREAS) WILL CONTINUE TO SLOWLY DRIVE TEMPERATURES DOWNWARD OVERNIGHT. OVERNIGHT LOWS WILL BE IN THE MID TO UPPER 20S MOST VALLEY AREAS... CLOSER TO 20 ACROSS THE HIGHER TERRAIN. && .SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/... LATER TODAY WILL BE MUCH COLDER THAN RECENT DAYS...WITH HIGHS GENERALLY REMAINING BELOW FREEZING ACROSS MUCH OF THE REGION. HIGHS WILL ONLY REACH THE 20S TO LOW 30S FOR MUCH OF THE AREA...WITH JUST TEENS OVER THE ADIRONDACKS. IN ADDITION...W-NW WINDS WILL CONTINUE TO BE 15-25 MPH AT TIMES...MAKING IT FEELS EVEN COLDER. THERE SHOULD BE A GOOD DEAL OF SUNSHINE FOR VALLEY AREAS...ALTHOUGH MORE CLOUDS AND A FEW PASSING FLURRIES ARE POSSIBLE IN FAR WESTERN AREAS...THANKS TO SOME LAKE MOISTURE TRYING TO MOVE INTO THE AREA. QUIET AND DRY WEATHER IS EXPECTED FOR FRI NIGHT INTO SATURDAY...WITH SFC HIGH PRESSURE NOT FAR FROM THE AREA. ALTHOUGH IT WILL BE CHILLY FOR FRI NIGHT...HEIGHTS ALOFT WILL START TO BE RISING ONCE AGAIN FOR SATURDAY. TEMPS WILL BE IN THE SINGLE DIGITS AND TEENS FOR FRIDAY NIGHT...AND RISE BACK INTO THE UPPER 20S TO UPPER 30S FOR SATURDAY. A STORM SYSTEM WILL BE SLIDING ACROSS THE UPPER GREAT LAKES ON SAT NIGHT. THERE WILL A STRONG W-SW FLOW AHEAD OF THIS APPROACHING SYSTEM...SO TEMPS WON/T BE QUITE AS COLD...WITH LOW TO MID LEVEL WARM AIR ADVECTION. LOWS WILL ONLY BE IN THE UPPER 20S TO LOW 30S FOR SAT NIGHT. && .LONG TERM /SUNDAY THROUGH THURSDAY/... CHANGEABLE CONDITIONS...ALONG WITH ANOTHER POTENTIAL STORM SYSTEM WILL IMPACT THE REGION DURING THE LONG TERM PERIOD...WITH OVERALL TEMPERATURES LIKELY REMAINING ABOVE NORMAL. INITIALLY...A CLIPPER TYPE SYSTEM IS EXPECTED TO TRACK NORTH OF THE GREAT LAKES AND INTO SOUTHEAST CANADA SUNDAY INTO MONDAY. A MILD SOUTHWEST FLOW AHEAD OF THIS FEATURE IS EXPECTED FOR SUNDAY AFTERNOON AND NIGHT. THERE COULD BE SOME SHOWERS OF RAIN...SNOW OR A LIGHT WINTRY MIX INITIALLY SUNDAY MORNING ACROSS EXTREME NORTHERN AREAS...AS A WEAK FRONTAL SYSTEM MAY BE CLOSE BY BEFORE LIFTING NORTHWARD IN THE AFTERNOON. THEN...MAINLY DRY CONDITIONS IN THE AFTERNOON...FOLLOWED BY INCREASING CHANCES OF SHOWERS OF RAIN AND SNOW FROM NW TO SE LATER SUNDAY NIGHT INTO MONDAY. AS THE FRONT PASSES ON MONDAY...STRONG GUSTY WINDS MAY DEVELOP. FOR MON NT-WED NT...THERE IS CONSIDERABLE UNCERTAINTY REGARDING THE NEXT POTENTIAL STORM SYSTEM. THE REMAINING FRONTAL SYSTEM FROM THE CLIPPER MAY REMAIN CLOSE BY...AS A SHORTWAVE TRANSLATES EAST LATE MON INTO TUE. THIS COULD ALLOW FOR SOME SNOW SHOWERS OR A PERIOD OF LIGHT SNOW SOMETIME TUESDAY OR TUESDAY NIGHT...ESP ACROSS CENTRAL OR NORTHERN AREAS. THEN...A POSSIBLE STRONGER LOW PRESSURE SYSTEM...SOMEWHAT SIMILAR TO THIS WEEK/S STORM...MAY TRACK TOWARD THE OHIO VALLEY REGION OR GREAT LAKES REGION ON WED. UNCERTAINTY REMAINS HIGH REGARDING THE POTENTIAL TRACK...AS THERE ARE SOME 12Z/25 GEFS MEMBERS THAT SUGGEST A MORE SOUTHERN TRACK...TOWARD THE MID ATLANTIC COAST...PLACING OUR REGION ON THE COLDER SIDE AND A POSSIBLE SNOW OR WINTRY MIX SITUATION. HOWEVER...THE MAJORITY OF DETERMINISTIC GUIDANCE SUGGESTS A MORE N/W TRACK...ALLOWING FOR A WARMER/WETTER SCENARIO OVERALL...AFTER A POSSIBLE WINTRY MIX ACROSS NORTHERN AREAS WED AM. WE HAVE SIDED WITH THIS OVERALL IDEA FOR NOW...WITH A WINTRY MIX WED AM FOR NORTHERN AREAS...AND RAIN ELSEWHERE...WITH MAINLY RAIN EXPECTED FOR THE REMAINDER OF THE REGION WED AFTERNOON/EVE...TAPERING TO SHOWERS OF RAIN AND SNOW IN THE STORM/S WAKE FOR THURSDAY. AS FOR TEMPS...WE EXPECT FAIRLY MILD CONDITIONS FOR SUNDAY AFTERNOON THROUGH MONDAY MORNING...ESP IN VALLEY AREAS...WHERE SUN AFTERNOON TEMPS COULD REACH INTO THE 50S...IF NOT WARMER. FOR AREAS MAINLY N AND W OF ALBANY...EXPECT AFTERNOON TEMPS TO REACH THE 40S. FOR SUN NT/MON AM...MOST TEMPS SHOULD REMAIN ABOVE FREEZING...GENERALLY IN THE 30S...ALTHOUGH IT IS POSSIBLE THAT SOME VALLEY AREAS FROM ALBANY SOUTH REMAIN ABOVE 40. THEN...MONDAY COULD STILL BE FAIRLY MILD DEPENDING ON THE TIMING OF THE COLD FRONT...WITH 40S POSSIBLE IN THE MORNING FOR VALLEYS...AND 30S ACROSS HIGHER ELEVATIONS...BEFORE TEMPS POSSIBLY FALL BACK INTO THE 20S AND 30S IN THE AFTERNOON. MON NT/TUE AM TEMPS SHOULD FALL INTO THE 20S...EXCEPT FOR TEENS ACROSS THE WESTERN ADIRONDACKS. FOR TUE-WED...LOTS OF UNCERTAINTY REGARDING TEMPS...WHICH WILL ULTIMATELY DEPEND ON THE TRACK OF THE LOW PRESSURE SYSTEM. FOR NOW...SIDED WITH MILDER GUIDANCE...WITH HIGHS IN THE 40S...EXCEPT FOR 30S ACROSS THE ADIRONDACKS...AND TUE NT/WED AM MINS MAINLY IN THE 20S TO LOWER 30S...BUT POSSIBLY SLIGHTLY COLDER ACROSS THE ADIRONDACKS. AGAIN...TEMPS COULD BE MUCH COLDER...OR EVEN SLIGHTLY WARMER THAN CURRENTLY FORECAST DEPENDING ON THE ULTIMATE TRACK OF THIS POSSIBLE STORM SYSTEM. FOR WED NT-THU...AS SLIGHTLY COLDER AIR BUILDS BACK IN...EXPECT MIN TEMPS TO FALL INTO THE 20S TO LOWER 30S...EXCEPT FOR SOME TEENS ACROSS THE ADIRONDACKS...AND THU MAX TEMPS MAINLY IN THE 30S TO LOWER 40S. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... UPSLOPE SNOWS WILL PRODUCE FREQUENT IFR CONDITIONS AT KPSF THROUGH 10Z...WHILE ONLY OCCASIONAL MVFR CONDITIONS IN SCATTERED SNOW SHOWERS AT THE REMAINING TAF SITES (INCLUDING KALB) THROUGH 10Z. OTHERWISE...VFR CONDITIONS WILL PREVAIL (BECOMING VFR AT KPSF AFTER 13Z). LOOK FOR THE CIGS TO BECOME SCATTERED AFTER 13Z AT ALL THE TERMINAL SITES. VISIBILITY OUTSIDE OF THE SNOW SHOWERS WILL BE UNRESTRICTED. A FRESH NORTHWEST BREEZE WILL PERSIST THROUGH TODAY AT ALL THE TAF SITES...10-15 KTS...BUT GUSTING TO 20KTS AT KPOU/KGFL AND 25KTS (OR A LITTLE HIGHER) AT KALB AND KPSF. THE WIND WILL SLOWLY DIMINISH AROUND DARK...BUT A GENTLE BREEZE WILL PERSIST INTO THE NIGHT TIME HOURS. OUTLOOK... FRIDAY NIGHT THROUGH SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. MONDAY: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHRA. MONDAY NIGHT THROUGH TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .HYDROLOGY... NO MORE RAIN IS EXPECTED FOR THE NEXT SEVERAL DAYS. ANYTHING THAT FALL OVERNIGHT WILL BE IN THE FORM OF SNOW SHOWERS WITH VIRTUALLY NO EFFECT ON RIVERS AND STREAMS. MOST...IF NOT ALL WATERSHEDS HAVE CRESTED AND WILL SLOWLY RECEDE DURING THE SEVERAL DAYS. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS/HWJIV NEAR TERM...HWJIV SHORT TERM...FRUGIS LONG TERM...KL AVIATION...HWJIV/KL HYDROLOGY...FRUGIS/HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
115 AM EST FRI FEB 26 2016 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE AND AN UPSLOPE WIND WILL ALLOW FOR NUMEROUS SNOW SHOWERS MAINLY OVER THE ELEVATED TERRAIN EAST OF THE HUDSON VALLEY OVERNIGHT...BRINGING SOME LIGHT TO LOCALLY MODERATE SNOWFALL ACCUMULATIONS. LIGHT SNOW SHOWERS WILL BE SCATTERED ACROSS THE REMAINDER OF THE REGION WITH LITTLE OR NO ACCUMULATIONS. HIGH PRESSURE WILL BUILD TO OUR SOUTH BRINGING AN END TO MOST OF THE SNOW SHOWERS LATER TODAY. IT WILL BE A PARTLY TO MOSTLY SUNNY BUT BRISK AND CHILLY DAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 115 AM EST...RADARS HAVE DETECTED ENHANCED AREAS OF UPSLOPE SNOW...MAINLY ACROSS THE ELEVATED TERRAIN TO THE EAST OF THE HUDSON VALLEY. SNOWFALL RATES LOOK TO BE AROUND HALF AN INCH PER HOUR AND WE DID HAVE ONE TWITTER REPORT OF MODERATE SNOWFALL IN LENOX MA. THIS UPSLOPE WAS DUE TO THE EFFECTS OF AN UPPER LEVEL DISTURBANCE/SHORT WAVE...COMBINED WITH CYCLONIC FLOW AND ENHANCED MOISTURE OFF LAKE ONTARIO. THE LATEST HRRR MODEL INDICATE THIS ACTIVITY SHOULD DIMINISH BY 400 AM OR SO AS THE UPPER SYSTEM MOVES AWAY...THE FLOW BECOMES MORE ANTICYCLONIC...DRYING THE COLUMN OUT. UNTIL THEN...1-3 INCHES OF SNOW SNOW LOOKS TO ACCUMULATE ALONG THE SPINE OF THE TACONICS...SOUTHERN GREENS...BERKSHIRES AND EVEN INTO THE LITCHFIELD HILLS. OTHER LESS IMPRESSIVE UPSLOPE SNOWS WERE NOTED ACROSS THE ADIRONDACKS WITH AMOUNTS CLOSER TO AN INCH. SCATTERED SNOW SHOWERS WERE DETECTED IN REMAINING AREAS...EVEN MOST VALLEY LOCATIONS...WITH A DUSTING POSSIBLE. ALL OF THIS ACTIVITY SHOULD DIMINISH BEFORE DAYBREAK. A NORTHWEST WIND 10-15 MPH...GUSTING TO OVER 30 MPH (ESPECIALLY IN THE WIND PRONE AREAS) WILL CONTINUE TO SLOWLY DRIVE TEMPERATURES DOWNWARD OVERNIGHT. OVERNIGHT LOWS WILL BE IN THE MID TO UPPER 20S MOST VALLEY AREAS... CLOSER TO 20 ACROSS THE HIGHER TERRAIN. && .SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/... LATER TODAY WILL BE MUCH COLDER THAN RECENT DAYS...WITH HIGHS GENERALLY REMAINING BELOW FREEZING ACROSS MUCH OF THE REGION. HIGHS WILL ONLY REACH THE 20S TO LOW 30S FOR MUCH OF THE AREA...WITH JUST TEENS OVER THE ADIRONDACKS. IN ADDITION...W-NW WINDS WILL CONTINUE TO BE 15-25 MPH AT TIMES...MAKING IT FEELS EVEN COLDER. THERE SHOULD BE A GOOD DEAL OF SUNSHINE FOR VALLEY AREAS...ALTHOUGH MORE CLOUDS AND A FEW PASSING FLURRIES ARE POSSIBLE IN FAR WESTERN AREAS...THANKS TO SOME LAKE MOISTURE TRYING TO MOVE INTO THE AREA. QUIET AND DRY WEATHER IS EXPECTED FOR FRI NIGHT INTO SATURDAY...WITH SFC HIGH PRESSURE NOT FAR FROM THE AREA. ALTHOUGH IT WILL BE CHILLY FOR FRI NIGHT...HEIGHTS ALOFT WILL START TO BE RISING ONCE AGAIN FOR SATURDAY. TEMPS WILL BE IN THE SINGLE DIGITS AND TEENS FOR FRIDAY NIGHT...AND RISE BACK INTO THE UPPER 20S TO UPPER 30S FOR SATURDAY. A STORM SYSTEM WILL BE SLIDING ACROSS THE UPPER GREAT LAKES ON SAT NIGHT. THERE WILL A STRONG W-SW FLOW AHEAD OF THIS APPROACHING SYSTEM...SO TEMPS WON/T BE QUITE AS COLD...WITH LOW TO MID LEVEL WARM AIR ADVECTION. LOWS WILL ONLY BE IN THE UPPER 20S TO LOW 30S FOR SAT NIGHT. && .LONG TERM /SUNDAY THROUGH THURSDAY/... CHANGEABLE CONDITIONS...ALONG WITH ANOTHER POTENTIAL STORM SYSTEM WILL IMPACT THE REGION DURING THE LONG TERM PERIOD...WITH OVERALL TEMPERATURES LIKELY REMAINING ABOVE NORMAL. INITIALLY...A CLIPPER TYPE SYSTEM IS EXPECTED TO TRACK NORTH OF THE GREAT LAKES AND INTO SOUTHEAST CANADA SUNDAY INTO MONDAY. A MILD SOUTHWEST FLOW AHEAD OF THIS FEATURE IS EXPECTED FOR SUNDAY AFTERNOON AND NIGHT. THERE COULD BE SOME SHOWERS OF RAIN...SNOW OR A LIGHT WINTRY MIX INITIALLY SUNDAY MORNING ACROSS EXTREME NORTHERN AREAS...AS A WEAK FRONTAL SYSTEM MAY BE CLOSE BY BEFORE LIFTING NORTHWARD IN THE AFTERNOON. THEN...MAINLY DRY CONDITIONS IN THE AFTERNOON...FOLLOWED BY INCREASING CHANCES OF SHOWERS OF RAIN AND SNOW FROM NW TO SE LATER SUNDAY NIGHT INTO MONDAY. AS THE FRONT PASSES ON MONDAY...STRONG GUSTY WINDS MAY DEVELOP. FOR MON NT-WED NT...THERE IS CONSIDERABLE UNCERTAINTY REGARDING THE NEXT POTENTIAL STORM SYSTEM. THE REMAINING FRONTAL SYSTEM FROM THE CLIPPER MAY REMAIN CLOSE BY...AS A SHORTWAVE TRANSLATES EAST LATE MON INTO TUE. THIS COULD ALLOW FOR SOME SNOW SHOWERS OR A PERIOD OF LIGHT SNOW SOMETIME TUESDAY OR TUESDAY NIGHT...ESP ACROSS CENTRAL OR NORTHERN AREAS. THEN...A POSSIBLE STRONGER LOW PRESSURE SYSTEM...SOMEWHAT SIMILAR TO THIS WEEK/S STORM...MAY TRACK TOWARD THE OHIO VALLEY REGION OR GREAT LAKES REGION ON WED. UNCERTAINTY REMAINS HIGH REGARDING THE POTENTIAL TRACK...AS THERE ARE SOME 12Z/25 GEFS MEMBERS THAT SUGGEST A MORE SOUTHERN TRACK...TOWARD THE MID ATLANTIC COAST...PLACING OUR REGION ON THE COLDER SIDE AND A POSSIBLE SNOW OR WINTRY MIX SITUATION. HOWEVER...THE MAJORITY OF DETERMINISTIC GUIDANCE SUGGESTS A MORE N/W TRACK...ALLOWING FOR A WARMER/WETTER SCENARIO OVERALL...AFTER A POSSIBLE WINTRY MIX ACROSS NORTHERN AREAS WED AM. WE HAVE SIDED WITH THIS OVERALL IDEA FOR NOW...WITH A WINTRY MIX WED AM FOR NORTHERN AREAS...AND RAIN ELSEWHERE...WITH MAINLY RAIN EXPECTED FOR THE REMAINDER OF THE REGION WED AFTERNOON/EVE...TAPERING TO SHOWERS OF RAIN AND SNOW IN THE STORM/S WAKE FOR THURSDAY. AS FOR TEMPS...WE EXPECT FAIRLY MILD CONDITIONS FOR SUNDAY AFTERNOON THROUGH MONDAY MORNING...ESP IN VALLEY AREAS...WHERE SUN AFTERNOON TEMPS COULD REACH INTO THE 50S...IF NOT WARMER. FOR AREAS MAINLY N AND W OF ALBANY...EXPECT AFTERNOON TEMPS TO REACH THE 40S. FOR SUN NT/MON AM...MOST TEMPS SHOULD REMAIN ABOVE FREEZING...GENERALLY IN THE 30S...ALTHOUGH IT IS POSSIBLE THAT SOME VALLEY AREAS FROM ALBANY SOUTH REMAIN ABOVE 40. THEN...MONDAY COULD STILL BE FAIRLY MILD DEPENDING ON THE TIMING OF THE COLD FRONT...WITH 40S POSSIBLE IN THE MORNING FOR VALLEYS...AND 30S ACROSS HIGHER ELEVATIONS...BEFORE TEMPS POSSIBLY FALL BACK INTO THE 20S AND 30S IN THE AFTERNOON. MON NT/TUE AM TEMPS SHOULD FALL INTO THE 20S...EXCEPT FOR TEENS ACROSS THE WESTERN ADIRONDACKS. FOR TUE-WED...LOTS OF UNCERTAINTY REGARDING TEMPS...WHICH WILL ULTIMATELY DEPEND ON THE TRACK OF THE LOW PRESSURE SYSTEM. FOR NOW...SIDED WITH MILDER GUIDANCE...WITH HIGHS IN THE 40S...EXCEPT FOR 30S ACROSS THE ADIRONDACKS...AND TUE NT/WED AM MINS MAINLY IN THE 20S TO LOWER 30S...BUT POSSIBLY SLIGHTLY COLDER ACROSS THE ADIRONDACKS. AGAIN...TEMPS COULD BE MUCH COLDER...OR EVEN SLIGHTLY WARMER THAN CURRENTLY FORECAST DEPENDING ON THE ULTIMATE TRACK OF THIS POSSIBLE STORM SYSTEM. FOR WED NT-THU...AS SLIGHTLY COLDER AIR BUILDS BACK IN...EXPECT MIN TEMPS TO FALL INTO THE 20S TO LOWER 30S...EXCEPT FOR SOME TEENS ACROSS THE ADIRONDACKS...AND THU MAX TEMPS MAINLY IN THE 30S TO LOWER 40S. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... UPSLOPE SNOWS WILL PRODUCE FREQUENT IFR CONDITIONS AT KPSF THROUGH 10Z...WHILE ONLY OCCASIONAL MVFR CONDITIONS IN SCATTERED SNOW SHOWERS AT THE REMAINING TAF SITES (INCLUDING KALB) THROUGH 10Z. OTHERWISE...VFR CONDITIONS WILL PREVAIL (BECOMING VFR AT KPSF AFTER 13Z). LOOK FOR THE CIGS TO BECOME SCATTERED AFTER 13Z AT ALL THE TERMINAL SITES. VISIBILITY OUTSIDE OF THE SNOW SHOWERS WILL BE UNRESTRICTED. A FRESH NORTHWEST BREEZE WILL PERSIST THROUGH TODAY AT ALL THE TAF SITES...10-15 KTS...BUT GUSTING TO 20KTS AT KPOU/KGFL AND 25KTS (OR A LITTLE HIGHER) AT KALB AND KPSF. THE WIND WILL SLOWLY DIMINISH AROUND DARK...BUT A GENTLE BREEZE WILL PERSIST INTO THE NIGHT TIME HOURS. OUTLOOK... FRIDAY NIGHT THROUGH SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. MONDAY: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHRA. MONDAY NIGHT THROUGH TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .HYDROLOGY... NO MORE RAIN IS EXPECTED FOR THE NEXT SEVERAL DAYS. ANYTHING THAT FALL OVERNIGHT WILL BE IN THE FORM OF SNOW SHOWERS WITH VIRTUALLY NO EFFECT ON RIVERS AND STREAMS. MOST...IF NOT ALL WATERSHEDS HAVE CRESTED AND WILL SLOWLY RECEDE DURING THE SEVERAL DAYS. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS/HWJIV NEAR TERM...HWJIV SHORT TERM...FRUGIS LONG TERM...KL AVIATION...HWJIV/KL HYDROLOGY...FRUGIS/HWJIV
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
139 AM EST FRI FEB 26 2016 .SYNOPSIS... ISSUED AT 105 AM EST THU FEB 26 2016 A WEAK FRONT WILL MOVE ACROSS THE AREA TONIGHT ACCOMPANIED BY SLIGHTLY COLDER TEMPERATURES. VERY LIGHT LAKE EFFECT SNOW SHOWERS WILL DIMINISH EARLY THIS MORNING WITH NOT MUCH MORE THAN A DUSTING OF SNOW. HIGH PRESSURE WILL BUILD IN TODAY AND SATURDAY PROVIDING QUIET WEATHER. A NICE WARM UP IS EXPECTED BUT THE RECENT SNOWPACK WILL TEMPER THE WARMTH INITIALLY. LOWS TONIGHT WILL BE MAINLY IN THE 20S. HIGHS TODAY WILL BE IN THE LOWER 30S. HIGHS WILL WARM INTO THE 40S SATURDAY AND 50S SUNDAY...ALONG WITH A CHANCE OF RAIN. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 336 PM EST THU FEB 25 2016 A MUCH QUIETER SHORT TERM AS SYNOPTIC SNOW COMES TO AN END AND WINDS CONTINUE TO DIMINISH TONIGHT. MAIN FOCUS ON LIGHT LAKE EFFECT TONIGHT. DRIER AIR WAS WORKING SOUTH AND SYNOPTIC SNOW WILL BE DONE BEFORE 00Z. HIRES GUIDANCE SHOWING LAKE EFFECT BANDS SETTING UP AROUND 00Z BUT RADAR RETURNS INDICATE LIGHT SNOW SHOWERS ALREADY DEVELOPING. WEAK MID LEVEL SHORT WAVE AND ASSOCIATED SFC TROUGH WILL BRING A THERMAL TROUGH ACROSS THE LAKE AND INVERSION HEIGHTS BRIEFLY RISE TO AROUND 5-6KFT FOR JUST A FEW HOURS THIS EVENING BEFORE COMING BACK DOWN TO AROUND 4KFT REST OF NIGHT. TRAJECTORIES AND DGZ FAVORABLE BUT INSTABILITY VERY LIMITED WITH DELTA T/S 13-14C. HRRR AND RUC13 HAVE BEEN RATHER CONSISTENT ALL DAY SHOWING LIGHT BANDS DEVELOPING WITH A FEW HUNDREDTHS QPF. GIVEN RADAR SIGNALS ALREADY HAVE SIDED TOWARD THE HIRES GUIDANCE. ARW-WRF HAS DONE WELL THIS SEASON WITH LES BANDS AND BLENDED IT WITH LATEST RUC FOR FORECAST. BANDS SHOWN BY MOST MODELS TO PENETRATE RATHER FAR INLAND AND DOWN TO CENTRAL IN AND INTO OHIO WITH HELP FROM SHORT WAVE. THEREFORE CARRIED LOW POPS ALL THE WAY TO SOUTHERN BORDER. STILL THINK ACCUMS WILL BE AN INCH OR LESS GIVEN THE LIMITING FACTORS BUT ISOLATED 2 POSSIBLE IN FAR NORTH IF A STRONGER BAND DEVELOPS IN BRIEF BUT PRIME WINDOW. OTHERWISE NOTHING SIGNIFICANT TO NOTE IN SHORT TERM. POSSIBILITY OF NORTHEAST BEING CLEAR AFTER SHORT WAVE WITH WINDS DROPPING OFF TO 5 KNOTS OR SO LATE TONIGHT. THIS COULD ALLOW TEMPS TO DROP RAPIDLY TOWARD SUNRISE WITH FRESH SNOWPACK. CONTINUED TO SIDE TOWARD OR BELOW LOWER END OF MOS. ALSO KEPT HIGHS IN LOWER END FRIDAY AND FRIDAY NIGHT. && .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 336 PM EST THU FEB 25 2016 WARM UP WILL BE UNDERWAY AT THE START OF THE PERIOD...INITIALLY INFLUENCED BY RIPENING AND SLOWLY MELTING SNOWPACK. AM HESITANT TO INCREASE TEMPS TOO MUCH ESPECIALLY WHERE 8 INCHES OR MORE OF SNOW CURRENTLY RESIDES AND AT LEAST 2 THAW/FREEZE CYCLES TO OCCUR BEFORE WE STAY ABOVE FREEZING STARTING SATURDAY. HAVE ALLOWED HIGHS TO REACH AT LEAST 40 ACROSS THE AREA WITH WARMEST READINGS IN FAR SOUTH. WENT SLIGHTLY WARMER ON SUNDAY AS WELL AS PACIFIC SYSTEM MOVES INTO THE GREAT LAKES AND BEGINS TO PULL UP AT LEAST SOME GULF MOISTURE LATE SUNDAY INTO SUNDAY NIGHT. NOT SURE IF DEEPER MSTR WILL PHASES IN TIME WITH THE SYSTEM TO WARRANT EXPANDED LIKELY OR EVEN CAT POPS SO HAVE LEFT PREVIOUS FORECAST GENERALLY UNTOUCHED. BEST CHANCE WILL BE ACROSS THE NORTH AND EAST CLOSER TO THE SFC LOW. WITH REGARDS TO PRECIP TYPE...ALL LIQUID PRECIP WILL BE SEEN INTO SUNDAY EVENING BEFORE A TRANSITION TO SNOW BY SUNDAY NIGHT. INFLUENCE OF SLIGHTLY COOLER AIR WILL BE SHORT AS MAIN FOCUS YET ANOTHER WAVE IN A VERY ACTIVE FLOW ENTERS THE NW STATES AND THEN BEGINS TO CARVE OUT A DEEPER TROUGH AS IT ENTERS THE PLAINS AND EVENTUALLY GREAT LAKES. ECMWF/GFS VARY ON HANDLING WITH ECMWF BRINGING A OPEN BUT EVENTUALLY NEGATIVELY TILTED WAVE MOVING THROUGH VS GFS CUTTING OFF A DEEP UPPER LOW TO TRACK ACROSS MI. LOTS OF SPECULATION WITH REGARDS TO IMPACTS ON THE AREA...BUT GIVEN NOTED DIFFERENCES...PERIOD OF INTEREST PAST DAY 5 AND CRITICAL THERMAL PROFILES/SFC LOW TRACK ALL IN QUESTIONS...HAVE TO CONSIDER JUST ABOUT ANY FORM OF PRECIP AND WEATHER POSSIBLE AT THIS JUNCTURE FROM FROZEN/FREEZING ALL THE WAY TO RAIN AND THUNDERSTORMS. CONFIDENCE NOT LIKELY TO INCREASE MUCH UNTIL LATE IN THE WEEKEND AS WAVE OF INTEREST BECOMES SAMPLED IN THE UPPER AIR NETWORK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 101 AM EST FRI FEB 26 2016 VFR CLOUDS WERE OVER NORTHERN INDIANA EARLY THIS MORNING EAST OF AN UPSTREAM RIDGE. WARMER AIR WITH VERY LITTLE MOISTURE WILL SPREAD INTO THE AREA AND WILL ALLOW SKIES TO CLEAR OVER THE AREA. A LARGE AREA OF CLEARING WAS ALREADY OVER THE UPPER MIDWEST. EXPECT THE LOW CLOUD DECK TO SCATTER OUT OVER NORTHERN INDIANA THIS AFTERNOON AND EARLY THIS EVENING. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR LMZ043-046. && $$ SYNOPSIS...AGD/SKIPPER SHORT TERM...LASHLEY LONG TERM...FISHER AVIATION...SKIPPER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1137 PM CST THU FEB 25 2016 .SHORT TERM /TONIGHT/... ISSUED AT 316 PM CST THU FEB 25 2016 LITTLE OF CONCERN TONIGHT OUTSIDE OF CLOUDS. MID LEVEL VORT LOBE CONTINUES TO DROP DOWN THE MID MS VALLEY BUT ANY ENHANCED VERTICAL MOTION IS ALREADY PAST IA. UPSTREAM SASKATCHEWAN/MANITOBA SHORT WAVE IS PRODUCING A FAINT REFLECTION OF HIGH CLOUDINESS...AND WHILE THE FORCING WILL BE WEAK TO MODERATE AS IT REACHES IA EARLY FRI MORNING STILL DO NOT EXPECT ANY PRECIP DUE TO A LACK OF MOISTURE. LIKELY JUST SCATTERED MID CLOUDS. THE ONLY SENSIBLE WEATHER OF NOTE WILL BE STRATUS TRENDS WITH PATCHY HOLES PASSING BY THIS EVENING...AND HIGH RES MODELS SUGGESTING MORE GENERAL CLEARING TOWARD DAYBREAK AS UPSTREAM LOW LEVEL RIDGE CROSS THE MO RIVER VALLEY. STAYED A TOUCH OVER MOS WITH CLOUDS EXPECTED TO BE PREVALENT FOR AWHILE. .LONG TERM /FRIDAY THROUGH THURSDAY/... ISSUED AT 316 PM CST THU FEB 25 2016 FEW CONCERNS IN THE EARLY PORTION OF THE EXTENDED. HRRR AND OTHER MESOSCALE MODELS SUGGEST THAT CLOUDS WILL HOLD ON THROUGH A PORTION OF FRIDAY MORNING...THEN BREAK UP LATE IN THE AFTERNOON AS ANOTHER WEAK WAVE PASSES EAST OF THE REGION BY 00Z SATURDAY. HIGHS FRIDAY WILL MODERATE AS THE WEAK SYSTEM APPROACHES FROM THE WEST. WARM AIR ADVECTION WITH LITTLE MOISTURE TRANSITIONS EAST INTO THE AREA FOR FRIDAY NIGHT INTO THE WEEKEND. VARIOUS SOLUTIONS HAVE H850 TEMPERATURES RISING TO +11C BY 00Z SUNDAY...WITH MIXING AT LEAST TAPPING INTO 8 TO 10C AIR BY LATE DAY. WILL CONTINUE TREND OF HIGHS IN THE 50S AND 60S ON SATURDAY AS SOUTH WINDS INCREASE TO 15 TO 25 MPH DURING THE DAY. LOWS SATURDAY NIGHT WILL BE QUITE MILD AS SOUTHWEST FLOW CONTINUES. BY 12Z SUNDAY THE COLD FRONT WILL BE NEARING THE I80 CORRIDOR...BUT ENOUGH RESIDUAL WARM AIR ALOFT AND A MILD START TO THE DAY WILL HELP HIGHS REACH THE MID TO UPPER 50S SOUTH. ACROSS THE NORTH BEHIND THE BOUNDARY...LIGHT RAIN AND CLOUDS WILL BEGIN TO FILL IN OVER THE REGION. THIS WILL KEEP TEMPERATURES COOLER NORTH WITH TEMPERATURES FALLING OFF DURING THE LATE AFTERNOON HOURS. WINDS SUNDAY AFTERNOON WITH GUSTS MAY BRIEFLY APPROACH 35 TO 40 MPH WITH THE PASSAGE OF THE COLD FRONT. BY SUNDAY NIGHT INTO MONDAY...WESTERLY FLOW WILL QUICKLY DISPLACE THE SLIGHT COLD AIR ADVECTION SUNDAY EVENING. THIS WILL RESULT IN A RENEWED WARM UP MONDAY WITH HIGHS BACK IN THE 40S/50S ACROSS THE STATE. THE REMAINDER OF THE EXTENDED FEATURES A LOW CONFIDENCE FORECAST AT THIS TIME...MODELS CONTINUE AT ODDS WITH THE TRACK AND EVOLUTION OF THE EARLY NEXT WEEK SYSTEM. TODAYS CONSENSUS SHOWS THAT THE TRACK MAY BE FARTHER NORTHWEST OF THE PREVIOUS TWO MODEL RUNS...RESULTING IN THE POTENTIAL FOR MORE ADVERSE WINTER CONDITIONS ACROSS PORTIONS OF OUR FORECAST AREA. GIVEN THAT WE ARE STILL 5-6 DAYS AWAY AND MODELS INHERENTLY STRUGGLE TO REACH A CORRECT SOLUTION AT THIS TIME RANGE...WILL CONTINUE TO GO WITH CHANCE POPS FOR NOW. THE MORE NORTHWEST DRIFT IN THE MODELS THE PAST 12 HOURS THOUGH WILL NEED TO BE MONITORED. WITH THE GFS ADVERTISING A MORE WOUND UP STORM THAN THE EURO AT THIS TIME DUE TO FASTER INGESTION OF COLD CANADIAN AIR...IT ALSO HAS STRONGER WINDS AND MORE PRECIPITATION FORECAST. AGREEMENT BETWEEN MODELS ON HEAVIEST PRECIPITATION AXIS/STRENGTH /TRACK IS CURRENTLY ALSO POOR. THE GENERAL TREND FOR BOTH THE GFS/EURO OF COOLER AND DRIER AIR RETURNING TO THE REGION WEDNESDAY WITH ANOTHER FAST MOVING SYSTEM SOMETIME AROUND THURSDAY. TEMPERATURES NEXT WEEK WILL GENERALLY BE IN THE 30S/40S WITH SOME UNCERTAINTY ON TUESDAY. WILL MENTION IN UPDATED HWO THIS AFTERNOON AND PASS ONTO SUCCEEDING SHIFT. && .AVIATION...26/06Z ISSUED AT 1137 PM CST THU FEB 25 2016 MVFR CIGS CONTINUE WITH NORTHWESTERLY WINDS. CLEARING STARTING TO MAKE IT INTO WESTERN IOWA AND SHOULD MOVE THROUGH THE MAJORITY OF THE TAF SITES THROUGH MID MORNING. WAS A LITTLE MORE PESSIMISTIC WITH THE CIGS...AS COULD SEE A LOBE OF LOWER CLOUDS MOVE BACK IN FOR A BRIEF PERIOD AROUND SUNRISE THROUGH LATE MORNING. OTHERWISE WINDS TO SHIFT AROUND TO THE SOUTH TO SOUTHWEST...WITH CLEAR SKIES FRIDAY EVENING. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...SMALL LONG TERM...REV AVIATION...BEERENDS
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
250 AM CST FRI FEB 26 2016 .SHORT TERM...(Today through Sunday night) Issued at 250 AM CST FRI FEB 26 2016 The low levels continue to slowly dry out as surface high pressure builds east from the Plains into the Mississippi Valley. Skies cleared out in some areas overnight, but areas of low clouds are returning from the north as of 08z. The main forecast issue for today is how much low cloudiness to expect. Model forecast soundings as well as the RAP 1000/850 mb layer mean rh suggest that low clouds will not be quick to leave our area. The deepest and most persistent moisture is forecast to remain across the Evansville tri-state area today, where the forecast will stay mostly cloudy. Elsewhere, there should be occasional sunshine today, especially in the far western areas around kpof. The mixed layer has become more shallow since yesterday, and there is little evidence of any forcing for ascent. Therefore, no mention of precip will be made. High temps will be only slightly higher than Thursday, ranging from the lower to mid 40s in most places. Tonight will become mainly clear as dry southwest flow nudges the low clouds out of our area. Low temps will average around 30 degrees. Saturday and Saturday night will remain mostly clear as a 500 mb shortwave ridge moves southeast across our region. Low-level southwest flow will bring moderating temps, with highs reaching 60 in parts of southeast Missouri Saturday. Sunday will be milder than Saturday, but the combination of strong southwest winds and increasing high cloudiness could make it feel cooler. The nam model has been showing 30 to 40 knots of wind in the mixed layer (below 3000 feet). Surface wind gusts should be within that range Sunday afternoon. A low-amplitude 500 mb shortwave trough and its associated cold front will move across our region on Sunday night. Moisture will be limited, since this system is embedded in northwest flow. Will maintain small rain chances, primarily along and east of the Mississippi River. .LONG TERM...(Monday through Thursday) Issued at 250 AM CST FRI FEB 26 2016 Models are struggling with the pattern in the long term. Basically used the latest ensemble mean solutions incorporated with 50 percent blend of our previous 2 official gridded forecasts. Should be dry Monday, with our attention on a developing upper level system over the Pacific NW, quickly headed for the Rockies. The models have this strong wave somewhere over the central Plains by 12z Tuesday. Will continue with slight chance PoPs for showers Monday night. Area wide convective chances Tuesday. The GFS is notably slower than the EC/GEM and other solutions. Will not completely discount it. Plan on giving the other model consensus more weight. Continue PoPs for rain/showers Tuesday night, though slightly lower, with diminishing PoPs Wednesday. Have little confidence in the models from Wednesday night into Thursday. Will carry slight/low chance PoPs given the 00z/12z EC solutions show weak s/wv energy may generate some precip (mainly rain, mix north 1/2?) during this time frame. Temps will be a blend of latest MOS and previous 2 forecast cycles. && .AVIATION... Issued at 250 AM CST FRI FEB 26 2016 VFR cigs will remain persistent through the day in the kevv/kowb areas. In the kpah/kcgi areas, expect occasional cigs in the vfr category. There will likely be short intervals of mvfr cigs at all sites, especially during the midday and afternoon hours. Low clouds will depart our region this evening, followed by mainly clear skies. No vsby issues are expected. Winds will be considerably lighter than the past couple of days as high pressure builds overhead. && .PAH Watches/Warnings/Advisories... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...MY LONG TERM...CN AVIATION...MY
AREA FORECAST DISCUSSION
NWS JACKSON KY
300 AM EST FRI FEB 26 2016 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM EST FRI FEB 26 2016 07Z SFC ANALYSIS SHOWS HIGH PRESSURE PUSHING INTO KENTUCKY FROM THE WEST WHILE A DEEP LOW IS FOUND TO THE NORTHEAST. THERE REMAINS A FAIRLY TIGHT PRESSURE GRADIENT BETWEEN THESE SYSTEMS KEEPING THE WINDS GOING THROUGH EAST KENTUCKY THIS NIGHT. THIS IS SUPPORTING A WELL MIXED AIR MASS MAKING TEMPERATURES FAIRLY UNIFORM ACROSS THE CWA. ADDITIONALLY...THESE WINDS ARE NOT ADVECTING IN MUCH COLDER AIR MEANING TEMPERATURES CURRENTLY ARE NEAR FREEZING ACROSS THE AREA BUT NOT MUCH COLDER. AS A RESULT...SOME OF THE LINGERING SNOW SHOWERS ARE PARTIALLY MELTING CAUSING SOME REPORTS OF SLEET AND DRIZZLE. THE BANDED NATURE OF THE PCPN EARLY THIS MORNING IS STILL MAKING IT POSSIBLE TO SEE BRIEF DUSTINGS OF ACCUMULATION FOR THE LOWER ELEVATIONS WHILE PLACES ABOVE 2000 FT COULD PICK UP ANOTHER HALF AN INCH OF ACCUMULATION OR SO THROUGH DAWN. FOR THAT REASON WILL MAINTAIN THE ADVISORY UNTIL 12Z IN THOSE PLACES ALONG WITH RUNNING THE SPS THROUGH THE MORNING COMMUTE FOR POTENTIAL SLICK SPOTS ELSEWHERE. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY ALL TAKE A DEEP TROUGH EAST AND AWAY FROM THE REGION. IN THE WAKE OF THIS...THE PATTERN WILL TEMPORARILY FLATTEN OUT BEFORE ANOTHER...WEAKER...TROUGH MOVES THROUGH THE OHIO VALLEY FRIDAY NIGHT INTO SATURDAY. RIDGING FOLLOWS FOR SATURDAY WITH SIGNIFICANT HEIGHT RISES OVER KENTUCKY WHILE THE CORE OF THE TROUGH SLIPS OFF THE SOUTHEAST COAST. GIVEN THE AGREEMENT AMONG THE MODELS HAVE FAVORED A BLENDED SOLUTION WITH A LEAN TOWARD THE HRRR AND NAM12 IN THE NEAR TERM. SENSIBLE WEATHER WILL FEATURE THE BULK OF ANY LINGERING SNOW SHOWERS ENDING AROUND DAWN ALONG WITH THE RISK FOR ACCUMULATIONS. SOME LIGHT SNOW SHOWERS AND FLURRIES WILL BE POSSIBLE IN THE FAR EAST THROUGH LATE AFTERNOON. TEMPERATURES BOTTOMING OUT FOR MOST PLACES IN THE LOWER 30S SHOULD LIMIT THE POTENTIAL FOR SLICK SPOTS THIS MORNING...PARTICULARLY WITH ROAD TEMPS IN THE MID AND UPPER 30S. SKIES WILL BE MOSTLY CLOUDY TODAY ALLOWING FOR LITTLE HELP FROM SUNSHINE IN TEMPERATURES RECOVERING...REACHING INTO THE MID 30S NORTHEAST TO LOWER 40S IN THE SOUTH. CLOUDY CONDITIONS WILL CONTINUE TO BE THE RULE INTO SATURDAY MORNING KEEPING THE DIURNAL RANGE OF TEMPERATURES TO A MINIMUM. ACCORDINGLY...READINGS WILL BE DOWN IN THE MID 20S TONIGHT AND AGAIN FAIRLY UNIFORM ACROSS THE ELEVATIONS. FOR SATURDAY...TEMPERATURES WILL MORE SOLIDLY REBOUND AS SUNSHINE RETURNS...AND THE WINDS SWITCH MORE TO THE SOUTH... ALLOWING READINGS TO CLIMB INTO THE UPPER 40S AND LOWER 50S. USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WIND GRIDS THROUGH THE DAY THEN USED THE SUPERBLEND THEREAFTER. MADE ONLY MINOR ADJUSTMENTS TO THE T GRIDS GIVEN THE LIMITED TERRAIN DIFFERENCES ANTICIPATED TONIGHT. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS FOR LINGERING SNOW SHOWERS AND FLURRIES THIS MORNING IN THE FAR EAST...OTHERWISE POP VALUES WERE KEPT IN THE SINGLE DIGITS THROUGH SATURDAY...IN LINE WITH THE MOS GUIDANCE. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 230 AM EST FRI FEB 26 2016 FORECAST CONFIDENCE REMAINS DECENT THROUGH MONDAY MORNING AS EVIDENCE BY GOOD AGREEMENT IN OPERATIONAL MODELS AND ENSEMBLES. HOWEVER...SPREAD IN MODELS INCREASES QUICKLY BEYOND MONDAY...LEADING TO LARGER UNCERTAINTIES FOR MUCH OF NEXT WEEK. THE PERIOD WILL START AS A MID LEVEL TROUGH CROSSES THE CENTRAL PLAINS ON SUNDAY WITH HEIGHTS CONTINUING TO BUILD ACROSS THE OHIO RIVER VALLEY. STRONG SOUTHWESTERLY FLOW WILL DEVELOP THROUGH THE DAY WITH TEMPERATURES JUMPING INTO THE 60S. GFS/NAM BUFKIT SOUNDINGS ARE SHOWING GOOD MIXING ON SUNDAY WITH WIND GUSTS TOPPING 30 OR 35 MPH. STRONGEST WIND GUSTS ARE EXPECTED ACROSS CENTRAL KENTUCKY. WILL INCLUDE A MENTION OF THE STRONG WINDS IN THE HWO. IF IT WASN`T FOR THE WET FUEL CONDITIONS...WE WOULD GET VERY CLOSE TO RED FLAG CONDITIONS AS THE RH SHOULD DROP FAIRLY LOW SUNDAY AFTERNOON. WILL HIGHLIGHT THE CRITICAL WEATHER CONDITIONS IN THE FIRE WEATHER FORECAST. AS THE SHORTWAVE TROUGH PUSHES ACROSS THE OHIO RIVER VALLEY SUNDAY NIGHT...A COLD FRONT WILL BE DRAGGED ACROSS EASTERN KENTUCKY WITH A BAND OF SCATTERED TO NUMEROUS SHOWERS. WITH MODELS IN FAIRLY GOOD AGREEMENT AND A MODEST DEPTH OF MOISTURE WITH THE FRONTAL PASSAGE. HAVE BUMPED POPS UP A CATEGORY. RAIN SHOULD MOVE ON THROUGH FAIRLY QUICKLY...WITH DRY WEATHER SPREADING BACK IN EARLY MONDAY MORNING. ATTENTION THEN TURNS TO A SYSTEM FOR THE MIDDLE OF NEXT WEEK. AS MENTIONED ABOVE...MID/UPPER LEVEL FEATURES ARE NOT IN GREAT AGREEMENT...SO CONFIDENCE IN STRENGTH AND TIMING OF THE MIDWEEK SYSTEM IS VERY MUCH IN QUESTION. HOWEVER...IT DOES APPEAR A WARM UP WILL BE ON TAP AHEAD OF THE SYSTEM FOR LATE MONDAY THROUGH TUESDAY...BEFORE COOLER WEATHER RETURNS FOR THE LATTER HALF OF THE WEEK. SOMEWHERE IN THAT WINDOW...CONFIDENCE IS INCREASING FOR ANOTHER ROUND OF RAIN. BEST CHANCES RIGHT NOW WOULD BE TUESDAY NIGHT INTO WEDNESDAY...BUT COULD EASILY BE SHIFTED FORWARD OR BACKWARD IN TIME AS MODELS SHIFT AROUND. WHILE IT DOES TURN COOLER BEHIND THE SYSTEM...THE STRENGTH OF THE SYSTEM WILL DETERMINE HOW MUCH COLD AIR GETS DRAGGED IN BEHIND THE DEPARTING SYSTEM AND IF WE SEE ANOTHER ROUND OF LIGHT SNOW SHOWER ACTIVITY. FOR NOW...WILL KEEP THINGS MORE RAIN AS WE HEAD INTO MARCH AND CONDITIONS BECOME MORE HOSTILE TO SNOW CHANCES. IT DOES APPEAR ANOTHER CLIPPER SYSTEM MAY FOLLOW LATER IN THE WEEK...BUT AGAIN UNCERTAINTY IS VERY HIGH BEYOND THE MID WEEK SYSTEM. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 125 AM EST FRI FEB 26 2016 CIGS WILL BE IN THE IFR AND MVFR RANGE THROUGH MID MORNING AS SCATTERED SNOW SHOWERS MOVE THROUGH EASTERN KENTUCKY. LOOK FOR CIGS TO LIFT INTO THE VFR RANGE DURING THE DAY FRIDAY FOR MOST SITES. HAVE KEPT VCSH IN THE TAFS THROUGH THE EARLY MORNING HOURS AS THESE MAINLY SNOW SHOWERS MOVE THROUGH. WINDS WILL REMAIN OUT OF THE NORTHWEST TO WEST AT 5 TO 10 KTS THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR KYZ087- 088-118-120. && $$ SHORT TERM...GREIF LONG TERM...KAS AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS CARIBOU ME
400 AM EST FRI FEB 26 2016 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TODAY WITH SOME LIGHT SNOW. HIGH PRESSURE WILL RIDGE ACROSS THE REGION TONIGHT INTO EARLY SATURDAT. ANOTHER COLD FRONT WILL CROSS THE REGION SATURDAY NIGHT INTO SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... COLDER AIR RETURNS FOR THIS TERM W/SOME SNOW EARLY TODAY. LATEST RADAR LOOP HAD PRECIP IN THE FORM OF SNOW MOVING ACROSS THE REGION IN RESPONSE TO A COLD FRONT MOVING ACROSS THE REGION. A BAND OF HEAVIER SNOW WAS MOVING ACROSS THE EASTERN SECTION OF AROOSTOOK COUNTY. THE LATEST NAM12 AND HRRR 3KM DOING WELL SHOWING A NICE CONVERGENCE ZONE IN THIS REGION W/A 35 KT AT 700 MBS MOVING ACROSS THE STATE. A QUICK INCH OF SNOW POSSIBLE AND WILL RE-FREEZING OF STANDING WATER, THIS WILL MAKE FOR ICY CONDITIONS. THE NAM SOUNDINGS INDICATE THAT SNOW SHOWERS WILL BE AROUND MAINLY ACROSS THE NORTH AND WEST INTO EARLY AFTERNOON AS UPPER TROF SWINGS ACROSS THE REGION. THE NAM INDICATED SOME DECENT VORTICITY ADVECTION W/THIS TROF TO HELP IGNITE SOME ACTIVITY. SNOW SQUALL PARAMETERS ARE NOT ALL IMPRESSIVE FOR HEAVIER ACTIVITY. MOISTURE IS THERE THROUGH 700MBS BUT LAPSE RATES NOT ALL IMPRESSIVE. THEREFORE, SNOWFALL FROM THESE SNOW SHOWERS WILL BE MAINLY LIGHT(LESS THAN AN INCH AT BEST). WNW WINDS WILL PICK UP TO 10-20 MPH ALLOWING FOR A BIT OF DRIFTING IN OPEN AREAS. NOTHING MAJOR. UPPER TROF SWINGS BY THIS EVENING W/HIGH PRES S OF THE REGION SET TO RIDGE ACROSS THE REGION OVERNIGHT. NW WINDS WILL DROP OFF BUT ARE FORECAST TO STAY UP AROUND 10 MPH. PARTIAL CLEARING WILL ALLOW FOR TEMPERATURES TO FALL OFF QUICKLY BUT THE WIND WILL ALLOW FOR SOME MIXING IN THE BLYR TO KEEP TEMPS FROM BOTTOMING OUT TOO LOW. MUCH COLDER HOWEVER THAN PREVIOUS NIGHTS W/AREAS BACK ACROSS THE ALLAGASH AND OUT WEST DROPPING AOB ZERO(0F) W/SINGLE NUMBERS EXPECTED FOR THE REST OF NORTHERN AND EASTERN MAINE. && .SHORT TERM /SATURDAY THROUGH SUNDAY/... HIGH PRESSURE WILL BUILD ACROSS THE REGION EARLY SATURDAY AND THEN MOVE EAST SATURDAY AFTERNOON IN ADVANCE OF AN APPROACHING COLD FRONT FROM THE NORTHWEST. EXPECT SUNSHINE TO GIVE WAY TO INCREASING AFTERNOON CLOUDS AND PERHAPS A FEW SNOW SHOWERS BY LATE IN THE DAY ACROSS FAR NORTHERN AREAS. HIGH TEMPERATURES ON SATURDAY WILL BE IN THE MID TO UPPER 20S NORTH AND LOWER 30S DOWNEAST. THE COLD FRONT WILL CROSS NORTHERN AREAS SATURDAY NIGHT AND THEN STALL IN THE VICINITY OF THE COAST SUNDAY. EXPECT A FEW SNOW SHOWERS ACROSS NORTHERN AREAS SATURDAY NIGHT WITH THE PASSAGE OF THE FRONT WITH DRY CONDITIONS DOWNEAST. LOWS SATURDAY NIGHT WILL GENERALLY RANGE FROM THE MID TEENS NORTH AND LOW TO MID 20 CENTRAL AND DOWN EAST. LOW PRESSURE WILL APPROACH FROM THE WEST SUNDAY WITH THE FRONT STARTING TO MOVE BACK TO THE NORTH AS A WARM FRONT. EXPECT SNOW TO DEVELOP ACROSS THE NORTH AND WEST LATER SUNDAY AFTERNOON WITH MAYBE AN INCH OR SO BY LATE SUNDAY AFTERNOON. ACROSS DOWNEAST AREAS EXPECT MAINLY CLOUDY SKIES. THERE WILL BE QUITE THE TEMPERATURE GRADIENT ON SUNDAY WITH HIGHS ACROSS THE NORTH MAINLY IN THE LOW TO MID 20S BUT IN THE MID 30S TO AROUND 40 ACROSS CENTRAL AND DOWNEAST. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... LOW PRESSURE WILL CONTINUE TO TRACK EAST TOWARD THE AREA SUNDAY NIGHT. A TIGHT THERMAL GRADIENT IN ASSOCIATION WITH A STRONG BAROCLINIC ZONE WILL SET UP ACROSS NORTHERN MOST MAINE SUPPORTING OVERRUNNING PRECIPITATION, MAINLY IN THE FORM OF SNOW ACROSS FAR NORTHERN MAINE. THE PRECIPITATION WILL CONTINUE INTO MONDAY BEFORE TAPERING TO SNOW SHOWERS LATER MONDAY AFTERNOON AS THE LOW TRACKS ACROSS TEH CANADIAN MARITIMES. THERE COULD BE SEVERAL INCHES OF SNOW ACROSS NORTHERN AREAS, ESPECIALLY THE SAINT JOHN VALLEY SUNDAY NIGHT AND INTO MONDAY. ACROSS CENTRAL AND DOWNEAST AREAS EXPECT MAINLY CLOUDY SKIES WITH THE CHANCE FOR RAIN SHOWERS. COLDER AIR WILL MOVE IN MONDAY NIGHT IN THE WAKE OF THE LOW WITH A FEW LINGERING SNOW SHOWERS POSSIBLE ACROSS NORTHERN AREAS AND PARTLY CLOUDY SKIES DOWNEAST. HIGH PRESSURE WILL BUILD EAST TOWARD THE AREA TUESDAY AND TUESDAY NIGHT. ANOTHER LOW PRESSURE SYSTEM WILL TRACK TOWARD THE AREA BY MID TO LATE WEEK BRINGING SOME SNOW OR EVEN RAIN TO THE REGION DEPENDING ON THE EXACT TRACK OF THE SYSTEM. && .AVIATION /07Z FRIDAY THROUGH TUESDAY/... NEAR TERM: MVFR FRO THE NORTHERN TERMINALS TODAY W/A TEMPO OF IFR THIS MORNING DUE TO SNOW. KBGR AND KBHB WILL SEE VFR FOR THE MOST PART TODAY W/A BRIEF PERIOD OF MVFR THIS MORNING. LOOK FOR IMPROVING CONDITIONS TONIGHT W/VFR FOR ALL TERMINALS. SHORT TERM: VFR SATURDAY ALL TERMINALS. MVFR IS POSSIBLE SATURDAY NIGHT AT THE NORTHERN TERMINALS IN SCT SNOW SHOWERS WITH VFR KBGR/KBHB. VFR THRU MUCH OF SUNDAY. IFR/LIFR CAN BE EXPECTED SUNDAY NIGHT AT THE NORTHERN TERMINALS IN SNOW WITH CONTINUED VFR KBGR/KBHB. THESE CONDITIONS WILL PERSIST INTO MONDAY. VFR RETURNS ALL TERMINALS MONDAY NIGHT THROUGH TUESDAY. && .MARINE... NEAR TERM: TRANSITIONED THE GALE WARNING TO A SCA INTO TONIGHT. WINDS HAVE DROPPED BACK TO 25 KTS W/SOME GUSTS TO 30 KT. A SURGE IN THE WINDS POSSIBLE LATER TODAY AS CAA HITS THE WARMER WATERS. SEAS ARE RUNNING 10-13 FT W/A SWELL COMPONENT FROM THE SE. PERIODS OF 11-12 SECONDS OUT THERE ATTM. THE SEA STATE WILL SUBSIDE TONIGHT AS THE WIND COMPONENT GOES OFFSHORE. SHORT TERM: A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED SATURDAY NIGHT AND SUNDAY. WINDS/SEAS ARE LIKELY TO CONTINUE AT SMALL CRAFT ADVISORY CONDITIONS THROUGH EARLY NEXT WEEK. && .HYDROLOGY... THE FLOOD WATCH REMAINS IN PLACE. SNOW FALLING AS COLDER AIR MOVING INTO THE REGION. THIS WILL BEGIN TO SLOW THINGS UP TODAY. RIVERS/STREAMS ARE HIGH W/SOME ICE MOVEMENT ESPECIALLY ON THE KINGSBURY STREAM IN PISCATAQUIS COUNTY. THREAT FOR MINOR FLOODING INCLUDING ICE JAM FLOODING IS STILL POSSIBLE ON THE SAINT JOHN...AROOSTOOK...PISCATAQUIS AND ALLAGASH RIVERS ALONG WITH SMALLER STREAMS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH UNTIL NOON EST TODAY FOR MEZ001>006-010-031. MARINE...GALE WARNING UNTIL 4 AM EST EARLY THIS MORNING FOR ANZ050>052. && $$ NEAR TERM...HEWITT SHORT TERM...DUDA LONG TERM...DUDA AVIATION...HEWITT/DUDA MARINE...HEWITT/DUDA HYDROLOGY...HEWITT
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1221 AM CST FRI FEB 26 2016 .UPDATE... ISSUED AT 1220 AM CST FRI FEB 26 2016 NO MAJOR CHANGES REQUIRED FOR THIS UPDATE. UPDATE ISSUED AT 939 PM CST THU FEB 25 2016 MID- AND HIGH-LEVEL CLOUD COVER IS HELPING PREVENT FREE-FALLING TEMPERATURES THIS EVENING DESPITE A BOUNDARY LAYER. WE HELD WITH PREVIOUS FORECAST LOWS FOR NOW EVEN THOUGH RECENT HIGH-RESOLUTION MODEL GUIDANCE KEYS ON THE CLOUD COVER AND ACTUALLY SUGGESTS LOWS WARMER THAN WE ARE ADVERTISING. OUR DECISION TO MAKE NO CHANGE TO OFFICIALLY-FORECAST LOWS IS BASED ON THE DRY AIR AND THE CLEARING ALREADY ADVANCING SOUTHEASTWARD ACROSS NORTHWEST ND PER EVENING SATELLITE IMAGERY. IN THE MEANTIME WE DID NEED TO INCREASE CLOUD COVER IN THE FORECAST...WHILE ADVERTISING A DECREASE OVERNIGHT. UPDATE ISSUED AT 554 PM CST THU FEB 25 2016 NO CHANGES OF NOTE WERE MADE WITH THIS UPDATE. LATE AFTERNOON MOISTURE CHANNEL IMAGES SHOW A SHORTWAVE TROUGH DROPPING SOUTH- EAST ACROSS SASKATCHEWAN. THAT WAVE IS RESPONSIBLE FOR THE HIGH- LEVEL CLOUDS ACROSS THE AREA...BUT MODEL GUIDANCE IS STILL VERY SUPPORTIVE OF A DRY AND QUIET NIGHT DESPITE THAT WAVE PASSAGE. THAT/S LARGELY DUE TO THE VERY DRY AIR MASS THAT EXISTS WITH 23 UTC SURFACE DEWPOINTS RANGING FROM THE SINGLE DIGITS F IN SOUTH- WEST ND TO THE TEENS F ELSEWHERE. THE DRY AIR MAY PROMOTE QUICK COOLING THIS EVENING SO WE WILL HAVE TO MONITOR TEMPERATURES IN CASE FORECAST LOWS ARE TOO OPTIMISTIC. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 129 PM CST THU FEB 25 2016 LATE THURSDAY AFTERNOON...A REGION OF SURFACE HIGH PRESSURE EXTENDED FROM THE SOUTHERN PROVINCES OF MANITOBA/SASKATCHEWAN SOUTH THROUGH THE CENTRAL PLAINS. STRATUS CLOUDS WERE RETREATING TO THE EAST AS LOW LEVEL WARM AIR ADVECTION WAS ERODING THE WESTERN EDGE. BY THIS EVENING THE STRATUS SHOULD HAVE RETREATED EAST OF THE JAMES RIVER VALLEY IN RESPONSE TO A WEST TO NORTHWEST WARM ADVECTIVE FLOW. THE HRRR DOES HINT AT SOME ISOLATED FOG NORTH CENTRAL BUT NOT ENOUGH SIGNAL TO PUT THAT IN THE FORECAST YET. ON FRIDAY...THE H500 RIDGE MOVES EAST TO THE CENTRAL AND NORTHERN PLAINS WITH BROAD WARM ADVECTION. WITH SUNNY SKIES FRIDAYS HIGHS WILL BE WELL INTO THE 50S WEST AND CENTRAL...WITH MID TO UPPER 40S JAMES RIVER VALLEY NORTH TO THE TURTLE MOUNTAINS. WITH GOOD MIXING HAVE RAISED MAX TEMPS 1 TO 2 DEGREES ABOVE THE CONSSHORT GUIDANCE FOR FRIDAY. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 129 PM CST THU FEB 25 2016 AN ACTIVE LONG TERM PERIOD. MAIN HIGHLIGHTS ARE A BRIEF BUT SIGNIFICANT WARMUP SATURDAY...FOLLOWED BY SUCCESSIVE COLD FRONTS ROUNDING OUT THE WEEKEND INTO EARLY NEXT WEEK PROMOTING A COOLING TREND. CHANCES OF SNOW ALSO RETURN WITH EACH SYSTEM THAT MOVES THROUGH. FRIDAY NIGHT THROUGH SATURDAY...WESTERN AND CENTRAL NORTH DAKOTA RESIDES IN THE WARM SECTOR. THE NAEFS/NORTH AMERICAN ENSEMBLE FORECAST SYSTEM SHOWS MODEL FORECASTS WITH REGARDS TO 850-500MB TEMPERATURES FALLING WITHIN THE 98TH/99TH PERCENTILE WITH RESPECT TO CLIMATOLOGY. NOT QUITE A MAXIMUM BUT CLOSE ENOUGH TO WHERE THESE ENSEMBLE TEMPERATURES REPRESENT AN EVENT THAT IS OUTSIDE THE 1979- 2000 CLIMATOLOGY FOR THIS TIME OF YEAR. RECORD HIGHS SATURDAY ARE AROUND 65 DEGREES FOR MOST OF THE MAJOR CITIES WITH THE RECORD AT JAMESTOWN OF 60 DEGREES. FORECAST HIGHS WILL MOSTLY RANGE BETWEEN 50F AND 62F. ALBEIT SHY OF RECORDS...THIS WILL STILL NEED SOME MONITORING AS WE GET CLOSER. A SURFACE COLD FRONT IMPINGES UPON NORTHWEST NORTH DAKOTA SATURDAY AFTERNOON WITH COLD AIR ADVECTION DEVELOPING. THIS COLD FRONT WILL SWEEP THROUGH ALL OF WESTERN AND CENTRAL NORTH DAKOTA SATURDAY NIGHT. A SLIGHT CHANCE OF RAIN SHOWERS IS FORECAST WEST SATURDAY EVENING...AND AS COLDER AIR ARRIVES SATURDAY NIGHT...EXPECT ANY PRECIPITATION TO CHANGE OVER TO LIGHT SNOW SHOWERS SATURDAY NIGHT. SUNDAY THROUGH TUESDAY...A QUICK TRANSITION FROM COLD AIR ADVECTION TO WARM AIR ADVECTION SUNDAY EVENING...THEN BACK TO COLD AIR ADVECTION SUNDAY NIGHT AND MONDAY AS AN ALBERTA CLIPPER PUSHES THROUGH. THE GFS AND ECMWF SHOW ANOTHER SHORTWAVE AND SURFACE LOW TO FOLLOW ON MONDAY. THIS SHORTWAVE MOVES FROM EASTERN MONTANA INTO WESTERN AND SOUTHERN NORTH DAKOTA MONDAY AFTERNOON THROUGH MONDAY NIGHT. CURRENTLY THE LONG TERM FORECAST GRIDS ONLY CARRY A SLIGHT CHANCE OF SNOW. THIS COULD CHANGE IF AGREEMENT AMONGST THE LONG TERM MODELS CONTINUE. TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...THE SYSTEM DEPARTS TUESDAY NIGHT WITH THE NEXT ONE COMING ACROSS WEDNESDAY INTO WEDNESDAY NIGHT. THE ECMWF IS STRONGER WITH PRECIPITATION CHANCES THAN THE GFS DURING THIS TIME PERIOD. THE SUPERBLEND CURRENTLY ADVERTISES CHANCES OF SNOW IN THE TURTLE MOUNTAINS ONLY. TEMPERATURES THROUGH AFTER SATURDAY IN THE LONG TERM PERIOD WILL TREND COOLER. HIGHS IN THE 40S SUNDAY WILL FALL BACK INTO THE 30S FOR THE MOST PART MONDAY THROUGH THURSDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1220 AM CST FRI FEB 26 2016 VFR AT ALL SITES THROUGH THE TAF PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AJ SHORT TERM...WAA LONG TERM...KS AVIATION...AJ
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
324 AM PST FRI FEB 26 2016 .SYNOPSIS...DRY WEATHER WITH ABOVE NORMAL TEMPERATURES THIS AFTERNOON. A WEAK SYSTEM WILL BRING A CHANCE FOR LIGHT RAIN, MAINLY NORTH OF INTERSTATE 80 THIS EVENING INTO EARLY SATURDAY... FOLLOWED BY AN EVEN WEAKER SYSTEM SUNDAY INTO MONDAY MORNING. && .DISCUSSION... Friday will start off similar to yesterday with some patchy fog this morning followed by warm and dry weather into this afternoon. Daytime highs will be a few degrees cooler than yesterday, but still several degrees above normal. Models in fairly good agreement that a weak trough will move inland this evening. The current HRRR shows precipitation moving into our CWA after 4 pm. The bulk of precipitation from this system continues to track north of I-80. The Sacramento region will likely only see a few hundredths of an inch while locations south of I-80 (Stockton- Modesto area) will probably stay dry or just see trace amounts of rain. Valley areas north of I-80 should range 0.05-0.25" with the higher amounts near Red Bluff and Redding. Mountain rain amounts will range 0.10" up to around a half inch with the Shasta County mountains and Lassen Peak having the highest amounts. Snow levels will stay above pass levels today and then lower overnight between 5500-6500 ft north of I-80 by early Saturday morning. However, any snow amounts that occur will be very light...a dusting up to around an inch or two at the higher peaks. Sierra travel on I-80 and Hwy 50 should see very minimal impacts, if any. Precipitation should end by late morning on Saturday giving way to another dry and warm afternoon/night. The next weak system is forecast to move across NorCal on Sunday with light rain hitting the coastal range and northern Sacramento Valley by late Sunday morning. Precipitation will then spread southward towards the I-80 corridor by Sunday afternoon into early Monday morning. Rain amounts will be lighter than the Fri-Sat system and, once again, snow will be an inch at best for the higher elevations north of I-80. Ridging re-develops over NorCal Monday into Tuesday. JBB && .EXTENDED DISCUSSION (Tuesday THROUGH Friday) Generally dry and mild weather is expected through the first half of next week. A weak system will pass over far Northern California Tuesday with light showers possible. Otherwise, temperatures are likely to peak on Wednesday, with highs roughly 5 to 10 degrees above normal. Models continue to indicate a stronger trough moving through around Thursday of next week. While not a strong system, this will likely be the first shot at region-wide precipitation in the next week. && && .AVIATION... General VFR conditions across interior NorCal the next 24 hours, except for isolated MVFR conditions in BR in the northern San Joaquin valley from 13Z to 17Z. Also, local MVFR possible over the mountains Friday night into Saturday morning as a weak system moves through. Breezy southwesterly winds over higher terrain tomorrow afternoon into Saturday morning. && .STO Watches/Warnings/Advisories... None. && $$
AREA FORECAST DISCUSSION...DELAYED
National Weather Service Lincoln IL
944 AM CST FRI FEB 26 2016 .UPDATE... ISSUED AT 944 AM CST FRI FEB 26 2016 Most of the CWA east of I-55 saw the lower level clouds scatter out and skies were mostly sunny this morning, although cirrus clouds were still streaming overhead. Another stratocumulus deck was along and west of the Illinois River, and this will overspread the forecast area over the next few hours. RAP model shows the lower clouds and cirrus on the way out by late afternoon, and will continue with the trend of decreasing clouds over the northwest CWA late this afternoon. Zones/grids were recently updated to address the sky trends, with minor updates to the temperatures. && .SHORT TERM...(Today) ISSUED AT 330 AM CST FRI FEB 26 2016 1032 mb high pressure over central Texas and ridging northward across the eastern plains, will see the ridge over IL by 18Z/noon today and into the Ohio river valley by sunset. This will keep central and southeast IL dry today, though a northern stream upper level trof over the Dakotas will dive southeast into MO and IL by early evening. This will tend to bring mostly cloudy skies and seasonably cool temperatures today. A large break in the low clouds across the nw half of CWA and moving southeast toward I-57 early this morning, should fill back in during the morning as upper level trof approaches and diurnal cumulus/stratocumulus clouds develop. WNW winds 7-15 mph this morning becomes WSW this afternoon. Still have a couple inches of snow on ground over east central IL and kept cooler highs in the mid to upper 30s there, while lower 40s elsewhere. .LONG TERM...(Tonight through Thursday) ISSUED AT 330 AM CST FRI FEB 26 2016 Northern stream upper level trof/short wave to exit quickly southeast into the mid MS and Ohio river valleys by 06z/midnight tonight with clouds decreasing from nw to SE during the night in its wake. Lows tonight of 25-30F with coolest readings over east central IL. Upper level heights rise over IL Saturday with upper level flow become semi-zonal and allowing Pacific air to flow into IL this weekend and bringing a nice warmup. Any remaining snow pack over east central IL to likely all melt on Saturday with ample sunshine with increasing SW winds 10-15 mph and gusts of 20-25 mph by Saturday afternoon. Milder highs Saturday in the 50s, ranging from lower 50s east central IL to the upper 50s west central IL. Lows Sat night in the upper 30s and lower 40s as fair skies continue. Low pressure emerging from the southern Canadian Rockies into the northern plains Saturday evening, tracks eastward across central WI and lower MI Sunday. Breezy SW winds of 15 to 25 mph and gusts of 25 to 35 mph Sunday brings even milder temps with highs in the low to mid 60s, despite increasing clouds as skies become mostly cloudy Sunday afternoon. Continued to carry slight chance of showers by mid/late Sunday afternoon over northern half of CWA while better chances of showers and even isolated thunderstorms over ne IL Sunday afternoon and early Sunday evening closer to low pressure moving across the central Great Lakes. This pulls a cold front southeast across central IL sunday evening bringing 20-30% chances of rain showers to central and eastern IL. Dry behind this front as clouds decrease overnight Sunday night and Monday and turning a bit cooler. Lows Sunday night in the low to mid 30s. Highs Monday 50-55F with mostly sunny skies and still above normal for last day of February. Big changes in the 00Z forecast models with track and speed of strong low pressure ejecting from KS on Tue. Yesterday models where taking low pressure ne across the ohio river valley Wed. Today the GEM and ECMWF model take low pressure into central IL by 18Z Tue and then into the eastern Great Lakes by 06Z/midnight Tue night. The GFS model is much slower with low pressure over ne KS at 18Z Tue and over central IL at 06Z/midnight Tue night. Will stay close to blended initialization pops with some lean toward the more similar ECMWF and GEM camps. Still dry Monday night over central/eastern IL then think rain showers to develop from west to east during the day Tue with isolated thunderstorms possible over southern IL. Leaning toward faster GEM/ECMWF model would have cooler air arriving quicker Tue night with rain changing to light snow showers, especially after midnight Tue night over central IL and just slight chances on Wed but GEM and ECMWF models have pcpn east of IL by Wed. This storm track over central IL would keep better chances of snow accumulations north of our CWA. Highs Tue range from upper 40s nw of IL river to near 60F by Lawrenceville. Much cooler Wed with brisk WNW winds and highs in mid to upper 30s central IL and lower 40s in southeast IL. A clipper system moves into IL from the northern Rockies Thu bringing a chance of rain/snow and below normal highs in the mid to upper 30s central IL and lower 40s southeast IL. && .AVIATION...(For the 12Z TAFS through 12Z Saturday morning) ISSUED AT 532 AM CST FRI FEB 26 2016 A hole in the clouds moved over all the sites during the overnight hours, but beginning at PIA around 13z, MVFR clouds around 2-2.5kft will move back into the area and effect all TAF sites this morning. CMI will remain clear the longest before the clouds arrive there around 18z. MVFR clouds will not clear until around 00z this evening and then skies should remain clear remainder of TAF period. The clear skies tonight, combined with winds becoming southerly, will produce fog over the areas where most of the snow melts today. So have included 2sm BR at CMI and DEC and BMI, where any snow cover should melt today and increase low level moisture for overnight. For PIA and SPI, will just have a TEMPO group of light fog. Winds will be northwest, then westerly most of the day, then light and variable this evening as the ridge moves through the area. Then winds will become southerly overnight. && .ILX Watches/Warnings/Advisories... NONE. && $$ UPDATE...Geelhart SHORT TERM...07 LONG TERM...07 AVIATION...Auten
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1057 AM EST FRI FEB 26 2016 .UPDATE... ISSUED AT 1057 AM EST FRI FEB 26 2016 HOURLY GRIDS WERE UPDATED BASED ON RECENT OBSERVATIONS AND RADAR TRENDS. THIS LED TO NO SUBSTANTIAL CHANGE OTHER THAN TO COOL OFF THE RIDGES A BIT THROUGH EARLY AFTERNOON. SINCE SNOW SHOWERS CONTINUE TO WIND DOWN TO ISOLATED SNOW SHOWERS AND FLURRIES AS THE LOW LEVEL FLOW WILL BECOME MORE WESTERLY AND LOW LEVEL MOISTURE MORE SHALLOW. THE SNOW SHOWERS HAVE ALSO SHIFTED INTO THE NORTHEASTERN AND EASTERN COUNTIES. THE SPS WAS EXTENDED THROUGH NOON SINCE RIDGETOPS REMAIN AT OR BELOW FREEZING ACROSS THE NORTH AND EASTERN PART OF THE AREA. UPDATE ISSUED AT 700 AM EST FRI FEB 26 2016 ALTHOUGH BANDS OF LIGHT SNOW SHOWERS AND FLURRIES WILL CONTINUE INTO MID MORNING ACROSS FAR EASTERN PARTS OF THE AREA WE WILL LET THE WINTER WEATHER ADVISORY EXPIRE AT 7 AM WITH LITTLE ADDITIONAL ACCUMULATION EXPECTED. THE SPS WILL CONTINUE THROUGH 9:30 FOR THE ENTIRE AREA DUE TO A POTENTIAL FOR SLICK SPOTS WITH THE LAST OF THE SNOW SHOWERS AROUND AND TEMPERATURES NEAR FREEZING. HAVE UPDATED THE GRIDS TO REFLECT THE CURRENT RADAR AND OB TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATED ZONES...HWO...AND THE EXPIRATION FOR THE WSW WILL FOLLOW SHORTLY. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM EST FRI FEB 26 2016 07Z SFC ANALYSIS SHOWS HIGH PRESSURE PUSHING INTO KENTUCKY FROM THE WEST WHILE A DEEP LOW IS FOUND TO THE NORTHEAST. THERE REMAINS A FAIRLY TIGHT PRESSURE GRADIENT BETWEEN THESE SYSTEMS KEEPING THE WINDS GOING THROUGH EAST KENTUCKY THIS NIGHT. THIS IS SUPPORTING A WELL MIXED AIR MASS MAKING TEMPERATURES FAIRLY UNIFORM ACROSS THE CWA. ADDITIONALLY...THESE WINDS ARE NOT ADVECTING IN MUCH COLDER AIR MEANING TEMPERATURES CURRENTLY ARE NEAR FREEZING ACROSS THE AREA BUT NOT MUCH COLDER. AS A RESULT...SOME OF THE LINGERING SNOW SHOWERS ARE PARTIALLY MELTING CAUSING SOME REPORTS OF SLEET AND DRIZZLE. THE BANDED NATURE OF THE PCPN EARLY THIS MORNING IS STILL MAKING IT POSSIBLE TO SEE BRIEF DUSTINGS OF ACCUMULATION FOR THE LOWER ELEVATIONS WHILE PLACES ABOVE 2000 FT COULD PICK UP ANOTHER HALF AN INCH OF ACCUMULATION OR SO THROUGH DAWN. FOR THAT REASON WILL MAINTAIN THE ADVISORY UNTIL 12Z IN THOSE PLACES ALONG WITH RUNNING THE SPS THROUGH THE MORNING COMMUTE FOR POTENTIAL SLICK SPOTS ELSEWHERE. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY ALL TAKE A DEEP TROUGH EAST AND AWAY FROM THE REGION. IN THE WAKE OF THIS...THE PATTERN WILL TEMPORARILY FLATTEN OUT BEFORE ANOTHER...WEAKER...TROUGH MOVES THROUGH THE OHIO VALLEY FRIDAY NIGHT INTO SATURDAY. RIDGING FOLLOWS FOR SATURDAY WITH SIGNIFICANT HEIGHT RISES OVER KENTUCKY WHILE THE CORE OF THE TROUGH SLIPS OFF THE SOUTHEAST COAST. GIVEN THE AGREEMENT AMONG THE MODELS HAVE FAVORED A BLENDED SOLUTION WITH A LEAN TOWARD THE HRRR AND NAM12 IN THE NEAR TERM. SENSIBLE WEATHER WILL FEATURE THE BULK OF ANY LINGERING SNOW SHOWERS ENDING AROUND DAWN ALONG WITH THE RISK FOR ACCUMULATIONS. SOME LIGHT SNOW SHOWERS AND FLURRIES WILL BE POSSIBLE IN THE FAR EAST THROUGH LATE AFTERNOON. TEMPERATURES BOTTOMING OUT FOR MOST PLACES IN THE LOWER 30S SHOULD LIMIT THE POTENTIAL FOR SLICK SPOTS THIS MORNING...PARTICULARLY WITH ROAD TEMPS IN THE MID AND UPPER 30S. SKIES WILL BE MOSTLY CLOUDY TODAY ALLOWING FOR LITTLE HELP FROM SUNSHINE IN TEMPERATURES RECOVERING...REACHING INTO THE MID 30S NORTHEAST TO LOWER 40S IN THE SOUTH. CLOUDY CONDITIONS WILL CONTINUE TO BE THE RULE INTO SATURDAY MORNING KEEPING THE DIURNAL RANGE OF TEMPERATURES TO A MINIMUM. ACCORDINGLY...READINGS WILL BE DOWN IN THE MID 20S TONIGHT AND AGAIN FAIRLY UNIFORM ACROSS THE ELEVATIONS. FOR SATURDAY...TEMPERATURES WILL MORE SOLIDLY REBOUND AS SUNSHINE RETURNS...AND THE WINDS SWITCH MORE TO THE SOUTH... ALLOWING READINGS TO CLIMB INTO THE UPPER 40S AND LOWER 50S. USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WIND GRIDS THROUGH THE DAY THEN USED THE SUPERBLEND THEREAFTER. MADE ONLY MINOR ADJUSTMENTS TO THE T GRIDS GIVEN THE LIMITED TERRAIN DIFFERENCES ANTICIPATED TONIGHT. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS FOR LINGERING SNOW SHOWERS AND FLURRIES THIS MORNING IN THE FAR EAST...OTHERWISE POP VALUES WERE KEPT IN THE SINGLE DIGITS THROUGH SATURDAY...IN LINE WITH THE MOS GUIDANCE. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 230 AM EST FRI FEB 26 2016 FORECAST CONFIDENCE REMAINS DECENT THROUGH MONDAY MORNING AS EVIDENCE BY GOOD AGREEMENT IN OPERATIONAL MODELS AND ENSEMBLES. HOWEVER...SPREAD IN MODELS INCREASES QUICKLY BEYOND MONDAY...LEADING TO LARGER UNCERTAINTIES FOR MUCH OF NEXT WEEK. THE PERIOD WILL START AS A MID LEVEL TROUGH CROSSES THE CENTRAL PLAINS ON SUNDAY WITH HEIGHTS CONTINUING TO BUILD ACROSS THE OHIO RIVER VALLEY. STRONG SOUTHWESTERLY FLOW WILL DEVELOP THROUGH THE DAY WITH TEMPERATURES JUMPING INTO THE 60S. GFS/NAM BUFKIT SOUNDINGS ARE SHOWING GOOD MIXING ON SUNDAY WITH WIND GUSTS TOPPING 30 OR 35 MPH. STRONGEST WIND GUSTS ARE EXPECTED ACROSS CENTRAL KENTUCKY. WILL INCLUDE A MENTION OF THE STRONG WINDS IN THE HWO. IF IT WASN`T FOR THE WET FUEL CONDITIONS...WE WOULD GET VERY CLOSE TO RED FLAG CONDITIONS AS THE RH SHOULD DROP FAIRLY LOW SUNDAY AFTERNOON. WILL HIGHLIGHT THE CRITICAL WEATHER CONDITIONS IN THE FIRE WEATHER FORECAST. AS THE SHORTWAVE TROUGH PUSHES ACROSS THE OHIO RIVER VALLEY SUNDAY NIGHT...A COLD FRONT WILL BE DRAGGED ACROSS EASTERN KENTUCKY WITH A BAND OF SCATTERED TO NUMEROUS SHOWERS. WITH MODELS IN FAIRLY GOOD AGREEMENT AND A MODEST DEPTH OF MOISTURE WITH THE FRONTAL PASSAGE. HAVE BUMPED POPS UP A CATEGORY. RAIN SHOULD MOVE ON THROUGH FAIRLY QUICKLY...WITH DRY WEATHER SPREADING BACK IN EARLY MONDAY MORNING. ATTENTION THEN TURNS TO A SYSTEM FOR THE MIDDLE OF NEXT WEEK. AS MENTIONED ABOVE...MID/UPPER LEVEL FEATURES ARE NOT IN GREAT AGREEMENT...SO CONFIDENCE IN STRENGTH AND TIMING OF THE MIDWEEK SYSTEM IS VERY MUCH IN QUESTION. HOWEVER...IT DOES APPEAR A WARM UP WILL BE ON TAP AHEAD OF THE SYSTEM FOR LATE MONDAY THROUGH TUESDAY...BEFORE COOLER WEATHER RETURNS FOR THE LATTER HALF OF THE WEEK. SOMEWHERE IN THAT WINDOW...CONFIDENCE IS INCREASING FOR ANOTHER ROUND OF RAIN. BEST CHANCES RIGHT NOW WOULD BE TUESDAY NIGHT INTO WEDNESDAY...BUT COULD EASILY BE SHIFTED FORWARD OR BACKWARD IN TIME AS MODELS SHIFT AROUND. WHILE IT DOES TURN COOLER BEHIND THE SYSTEM...THE STRENGTH OF THE SYSTEM WILL DETERMINE HOW MUCH COLD AIR GETS DRAGGED IN BEHIND THE DEPARTING SYSTEM AND IF WE SEE ANOTHER ROUND OF LIGHT SNOW SHOWER ACTIVITY. FOR NOW...WILL KEEP THINGS MORE RAIN AS WE HEAD INTO MARCH AND CONDITIONS BECOME MORE HOSTILE TO SNOW CHANCES. IT DOES APPEAR ANOTHER CLIPPER SYSTEM MAY FOLLOW LATER IN THE WEEK...BUT AGAIN UNCERTAINTY IS VERY HIGH BEYOND THE MID WEEK SYSTEM. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 630 AM EST FRI FEB 26 2016 CIGS WILL BE GENERALLY IN THE LOW VFR RANGE THROUGH THE PERIOD WITH OCCASIONAL BOUTS OF MVFR THIS MORNING AS THE LAST OF THE LIGHT SNOW SHOWERS DEPART THE AREA. WINDS WILL REMAIN OUT OF THE NORTHWEST TO WEST AT 5 TO 10 KTS THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...KAS AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
700 AM EST FRI FEB 26 2016 .UPDATE... ISSUED AT 700 AM EST FRI FEB 26 2016 ALTHOUGH BANDS OF LIGHT SNOW SHOWERS AND FLURRIES WILL CONTINUE INTO MID MORNING ACROSS FAR EASTERN PARTS OF THE AREA WE WILL LET THE WINTER WEATHER ADVISORY EXPIRE AT 7 AM WITH LITTLE ADDITIONAL ACCUMULATION EXPECTED. THE SPS WILL CONTINUE THROUGH 9:30 FOR THE ENTIRE AREA DUE TO A POTENTIAL FOR SLICK SPOTS WITH THE LAST OF THE SNOW SHOWERS AROUND AND TEMPERATURES NEAR FREEZING. HAVE UPDATED THE GRIDS TO REFLECT THE CURRENT RADAR AND OB TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATED ZONES...HWO...AND THE EXPIRATION FOR THE WSW WILL FOLLOW SHORTLY. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM EST FRI FEB 26 2016 07Z SFC ANALYSIS SHOWS HIGH PRESSURE PUSHING INTO KENTUCKY FROM THE WEST WHILE A DEEP LOW IS FOUND TO THE NORTHEAST. THERE REMAINS A FAIRLY TIGHT PRESSURE GRADIENT BETWEEN THESE SYSTEMS KEEPING THE WINDS GOING THROUGH EAST KENTUCKY THIS NIGHT. THIS IS SUPPORTING A WELL MIXED AIR MASS MAKING TEMPERATURES FAIRLY UNIFORM ACROSS THE CWA. ADDITIONALLY...THESE WINDS ARE NOT ADVECTING IN MUCH COLDER AIR MEANING TEMPERATURES CURRENTLY ARE NEAR FREEZING ACROSS THE AREA BUT NOT MUCH COLDER. AS A RESULT...SOME OF THE LINGERING SNOW SHOWERS ARE PARTIALLY MELTING CAUSING SOME REPORTS OF SLEET AND DRIZZLE. THE BANDED NATURE OF THE PCPN EARLY THIS MORNING IS STILL MAKING IT POSSIBLE TO SEE BRIEF DUSTINGS OF ACCUMULATION FOR THE LOWER ELEVATIONS WHILE PLACES ABOVE 2000 FT COULD PICK UP ANOTHER HALF AN INCH OF ACCUMULATION OR SO THROUGH DAWN. FOR THAT REASON WILL MAINTAIN THE ADVISORY UNTIL 12Z IN THOSE PLACES ALONG WITH RUNNING THE SPS THROUGH THE MORNING COMMUTE FOR POTENTIAL SLICK SPOTS ELSEWHERE. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY ALL TAKE A DEEP TROUGH EAST AND AWAY FROM THE REGION. IN THE WAKE OF THIS...THE PATTERN WILL TEMPORARILY FLATTEN OUT BEFORE ANOTHER...WEAKER...TROUGH MOVES THROUGH THE OHIO VALLEY FRIDAY NIGHT INTO SATURDAY. RIDGING FOLLOWS FOR SATURDAY WITH SIGNIFICANT HEIGHT RISES OVER KENTUCKY WHILE THE CORE OF THE TROUGH SLIPS OFF THE SOUTHEAST COAST. GIVEN THE AGREEMENT AMONG THE MODELS HAVE FAVORED A BLENDED SOLUTION WITH A LEAN TOWARD THE HRRR AND NAM12 IN THE NEAR TERM. SENSIBLE WEATHER WILL FEATURE THE BULK OF ANY LINGERING SNOW SHOWERS ENDING AROUND DAWN ALONG WITH THE RISK FOR ACCUMULATIONS. SOME LIGHT SNOW SHOWERS AND FLURRIES WILL BE POSSIBLE IN THE FAR EAST THROUGH LATE AFTERNOON. TEMPERATURES BOTTOMING OUT FOR MOST PLACES IN THE LOWER 30S SHOULD LIMIT THE POTENTIAL FOR SLICK SPOTS THIS MORNING...PARTICULARLY WITH ROAD TEMPS IN THE MID AND UPPER 30S. SKIES WILL BE MOSTLY CLOUDY TODAY ALLOWING FOR LITTLE HELP FROM SUNSHINE IN TEMPERATURES RECOVERING...REACHING INTO THE MID 30S NORTHEAST TO LOWER 40S IN THE SOUTH. CLOUDY CONDITIONS WILL CONTINUE TO BE THE RULE INTO SATURDAY MORNING KEEPING THE DIURNAL RANGE OF TEMPERATURES TO A MINIMUM. ACCORDINGLY...READINGS WILL BE DOWN IN THE MID 20S TONIGHT AND AGAIN FAIRLY UNIFORM ACROSS THE ELEVATIONS. FOR SATURDAY...TEMPERATURES WILL MORE SOLIDLY REBOUND AS SUNSHINE RETURNS...AND THE WINDS SWITCH MORE TO THE SOUTH... ALLOWING READINGS TO CLIMB INTO THE UPPER 40S AND LOWER 50S. USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WIND GRIDS THROUGH THE DAY THEN USED THE SUPERBLEND THEREAFTER. MADE ONLY MINOR ADJUSTMENTS TO THE T GRIDS GIVEN THE LIMITED TERRAIN DIFFERENCES ANTICIPATED TONIGHT. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS FOR LINGERING SNOW SHOWERS AND FLURRIES THIS MORNING IN THE FAR EAST...OTHERWISE POP VALUES WERE KEPT IN THE SINGLE DIGITS THROUGH SATURDAY...IN LINE WITH THE MOS GUIDANCE. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 230 AM EST FRI FEB 26 2016 FORECAST CONFIDENCE REMAINS DECENT THROUGH MONDAY MORNING AS EVIDENCE BY GOOD AGREEMENT IN OPERATIONAL MODELS AND ENSEMBLES. HOWEVER...SPREAD IN MODELS INCREASES QUICKLY BEYOND MONDAY...LEADING TO LARGER UNCERTAINTIES FOR MUCH OF NEXT WEEK. THE PERIOD WILL START AS A MID LEVEL TROUGH CROSSES THE CENTRAL PLAINS ON SUNDAY WITH HEIGHTS CONTINUING TO BUILD ACROSS THE OHIO RIVER VALLEY. STRONG SOUTHWESTERLY FLOW WILL DEVELOP THROUGH THE DAY WITH TEMPERATURES JUMPING INTO THE 60S. GFS/NAM BUFKIT SOUNDINGS ARE SHOWING GOOD MIXING ON SUNDAY WITH WIND GUSTS TOPPING 30 OR 35 MPH. STRONGEST WIND GUSTS ARE EXPECTED ACROSS CENTRAL KENTUCKY. WILL INCLUDE A MENTION OF THE STRONG WINDS IN THE HWO. IF IT WASN`T FOR THE WET FUEL CONDITIONS...WE WOULD GET VERY CLOSE TO RED FLAG CONDITIONS AS THE RH SHOULD DROP FAIRLY LOW SUNDAY AFTERNOON. WILL HIGHLIGHT THE CRITICAL WEATHER CONDITIONS IN THE FIRE WEATHER FORECAST. AS THE SHORTWAVE TROUGH PUSHES ACROSS THE OHIO RIVER VALLEY SUNDAY NIGHT...A COLD FRONT WILL BE DRAGGED ACROSS EASTERN KENTUCKY WITH A BAND OF SCATTERED TO NUMEROUS SHOWERS. WITH MODELS IN FAIRLY GOOD AGREEMENT AND A MODEST DEPTH OF MOISTURE WITH THE FRONTAL PASSAGE. HAVE BUMPED POPS UP A CATEGORY. RAIN SHOULD MOVE ON THROUGH FAIRLY QUICKLY...WITH DRY WEATHER SPREADING BACK IN EARLY MONDAY MORNING. ATTENTION THEN TURNS TO A SYSTEM FOR THE MIDDLE OF NEXT WEEK. AS MENTIONED ABOVE...MID/UPPER LEVEL FEATURES ARE NOT IN GREAT AGREEMENT...SO CONFIDENCE IN STRENGTH AND TIMING OF THE MIDWEEK SYSTEM IS VERY MUCH IN QUESTION. HOWEVER...IT DOES APPEAR A WARM UP WILL BE ON TAP AHEAD OF THE SYSTEM FOR LATE MONDAY THROUGH TUESDAY...BEFORE COOLER WEATHER RETURNS FOR THE LATTER HALF OF THE WEEK. SOMEWHERE IN THAT WINDOW...CONFIDENCE IS INCREASING FOR ANOTHER ROUND OF RAIN. BEST CHANCES RIGHT NOW WOULD BE TUESDAY NIGHT INTO WEDNESDAY...BUT COULD EASILY BE SHIFTED FORWARD OR BACKWARD IN TIME AS MODELS SHIFT AROUND. WHILE IT DOES TURN COOLER BEHIND THE SYSTEM...THE STRENGTH OF THE SYSTEM WILL DETERMINE HOW MUCH COLD AIR GETS DRAGGED IN BEHIND THE DEPARTING SYSTEM AND IF WE SEE ANOTHER ROUND OF LIGHT SNOW SHOWER ACTIVITY. FOR NOW...WILL KEEP THINGS MORE RAIN AS WE HEAD INTO MARCH AND CONDITIONS BECOME MORE HOSTILE TO SNOW CHANCES. IT DOES APPEAR ANOTHER CLIPPER SYSTEM MAY FOLLOW LATER IN THE WEEK...BUT AGAIN UNCERTAINTY IS VERY HIGH BEYOND THE MID WEEK SYSTEM. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 630 AM EST FRI FEB 26 2016 CIGS WILL BE GENERALLY IN THE LOW VFR RANGE THROUGH THE PERIOD WITH OCCASIONAL BOUTS OF MVFR THIS MORNING AS THE LAST OF THE LIGHT SNOW SHOWERS DEPART THE AREA. WINDS WILL REMAIN OUT OF THE NORTHWEST TO WEST AT 5 TO 10 KTS THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...GREIF LONG TERM...KAS AVIATION...GREIF
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
530 AM CST FRI FEB 26 2016 .UPDATE... Updated aviation section for 12z taf issuance && .SHORT TERM...(Today through Sunday night) Issued at 250 AM CST FRI FEB 26 2016 The low levels continue to slowly dry out as surface high pressure builds east from the Plains into the Mississippi Valley. Skies cleared out in some areas overnight, but areas of low clouds are returning from the north as of 08z. The main forecast issue for today is how much low cloudiness to expect. Model forecast soundings as well as the RAP 1000/850 mb layer mean rh suggest that low clouds will not be quick to leave our area. The deepest and most persistent moisture is forecast to remain across the Evansville tri-state area today, where the forecast will stay mostly cloudy. Elsewhere, there should be occasional sunshine today, especially in the far western areas around kpof. The mixed layer has become more shallow since yesterday, and there is little evidence of any forcing for ascent. Therefore, no mention of precip will be made. High temps will be only slightly higher than Thursday, ranging from the lower to mid 40s in most places. Tonight will become mainly clear as dry southwest flow nudges the low clouds out of our area. Low temps will average around 30 degrees. Saturday and Saturday night will remain mostly clear as a 500 mb shortwave ridge moves southeast across our region. Low-level southwest flow will bring moderating temps, with highs reaching 60 in parts of southeast Missouri Saturday. Sunday will be milder than Saturday, but the combination of strong southwest winds and increasing high cloudiness could make it feel cooler. The nam model has been showing 30 to 40 knots of wind in the mixed layer (below 3000 feet). Surface wind gusts should be within that range Sunday afternoon. A low-amplitude 500 mb shortwave trough and its associated cold front will move across our region on Sunday night. Moisture will be limited, since this system is embedded in northwest flow. Will maintain small rain chances, primarily along and east of the Mississippi River. .LONG TERM...(Monday through Thursday) Issued at 250 AM CST FRI FEB 26 2016 Models are struggling with the pattern in the long term. Basically used the latest ensemble mean solutions incorporated with 50 percent blend of our previous 2 official gridded forecasts. Should be dry Monday, with our attention on a developing upper level system over the Pacific NW, quickly headed for the Rockies. The models have this strong wave somewhere over the central Plains by 12z Tuesday. Will continue with slight chance PoPs for showers Monday night. Area wide convective chances Tuesday. The GFS is notably slower than the EC/GEM and other solutions. Will not completely discount it. Plan on giving the other model consensus more weight. Continue PoPs for rain/showers Tuesday night, though slightly lower, with diminishing PoPs Wednesday. Have little confidence in the models from Wednesday night into Thursday. Will carry slight/low chance PoPs given the 00z/12z EC solutions show weak s/wv energy may generate some precip (mainly rain, mix north 1/2?) during this time frame. Temps will be a blend of latest MOS and previous 2 forecast cycles. && .AVIATION... Issued at 530 AM CST FRI FEB 26 2016 VFR cigs will remain persistent through the day in the kevv/kowb areas. In the kpah/kcgi areas, mvfr to vfr cigs around 3k feet are returning as of 11z. There will likely be intervals of mvfr cigs at all sites through the mid-afternoon hours. Low clouds will depart our region late this afternoon and early this evening, followed by a mid-level cloud deck above 10k feet. No vsby issues are expected. Winds will be considerably lighter than the past couple of days as high pressure builds overhead. && .PAH Watches/Warnings/Advisories... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...MY LONG TERM...CN AVIATION...MY
AREA FORECAST DISCUSSION
NWS CARIBOU ME
614 AM EST FRI FEB 26 2016 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE AREA TODAY WITH SOME LIGHT SNOW. HIGH PRESSURE WILL RIDGE ACROSS THE REGION TONIGHT INTO EARLY SATURDAY. ANOTHER COLD FRONT WILL CROSS THE REGION SATURDAY NIGHT INTO SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... 615 AM UPDATE: STEADY LIGHT SNOW MOVING ACROSS THE REGION AHEAD OF THE COLD FRONT. SNOW HAS EXTENDING ITS WAY DOWN INTO CENTRAL PENOBSCOT COUNTY AND HANCOCK COUNTY. THEREFORE, INCREASE THE PERCENTAGES(POPS) W/THE MENTION OF SNOW IN THESE AREAS W/LIGHT ACCUMULATIONS. STILL LOOKING FOR AROUND AN INCH OR SO ACROSS NORTHERN AREAS. HRLY TEMPS NEEDED ADJUSTMENT TO BRING THEM UP A FEW DEGREES USING THE ADJLAV GUIDANCE WHICH APPEARS TO BE DOING WELL ATTM. PREVIOUS DISCUSSION... COLDER AIR RETURNS FOR THIS TERM W/SOME SNOW EARLY TODAY. LATEST RADAR LOOP HAD PRECIP IN THE FORM OF SNOW MOVING ACROSS THE REGION IN RESPONSE TO A COLD FRONT MOVING ACROSS THE REGION. A BAND OF HEAVIER SNOW WAS MOVING ACROSS THE EASTERN SECTION OF AROOSTOOK COUNTY. THE LATEST NAM12 AND HRRR 3KM DOING WELL SHOWING A NICE CONVERGENCE ZONE IN THIS REGION W/A 35 KT AT 700 MBS MOVING ACROSS THE STATE. A QUICK INCH OF SNOW POSSIBLE AND WILL RE-FREEZING OF STANDING WATER, THIS WILL MAKE FOR ICY CONDITIONS. THE NAM SOUNDINGS INDICATE THAT SNOW SHOWERS WILL BE AROUND MAINLY ACROSS THE NORTH AND WEST INTO EARLY AFTERNOON AS UPPER TROF SWINGS ACROSS THE REGION. THE NAM INDICATED SOME DECENT VORTICITY ADVECTION W/THIS TROF TO HELP IGNITE SOME ACTIVITY. SNOW SQUALL PARAMETERS ARE NOT ALL IMPRESSIVE FOR HEAVIER ACTIVITY. MOISTURE IS THERE THROUGH 700MBS BUT LAPSE RATES NOT ALL IMPRESSIVE. THEREFORE, SNOWFALL FROM THESE SNOW SHOWERS WILL BE MAINLY LIGHT(LESS THAN AN INCH AT BEST). WNW WINDS WILL PICK UP TO 10-20 MPH ALLOWING FOR A BIT OF DRIFTING IN OPEN AREAS. NOTHING MAJOR. UPPER TROF SWINGS BY THIS EVENING W/HIGH PRES S OF THE REGION SET TO RIDGE ACROSS THE REGION OVERNIGHT. NW WINDS WILL DROP OFF BUT ARE FORECAST TO STAY UP AROUND 10 MPH. PARTIAL CLEARING WILL ALLOW FOR TEMPERATURES TO FALL OFF QUICKLY BUT THE WIND WILL ALLOW FOR SOME MIXING IN THE BLYR TO KEEP TEMPS FROM BOTTOMING OUT TOO LOW. MUCH COLDER HOWEVER THAN PREVIOUS NIGHTS W/AREAS BACK ACROSS THE ALLAGASH AND OUT WEST DROPPING AOB ZERO(0F) W/SINGLE NUMBERS EXPECTED FOR THE REST OF NORTHERN AND EASTERN MAINE. && .SHORT TERM /SATURDAY THROUGH SUNDAY/... HIGH PRESSURE WILL BUILD ACROSS THE REGION EARLY SATURDAY AND THEN MOVE EAST SATURDAY AFTERNOON IN ADVANCE OF AN APPROACHING COLD FRONT FROM THE NORTHWEST. EXPECT SUNSHINE TO GIVE WAY TO INCREASING AFTERNOON CLOUDS AND PERHAPS A FEW SNOW SHOWERS BY LATE IN THE DAY ACROSS FAR NORTHERN AREAS. HIGH TEMPERATURES ON SATURDAY WILL BE IN THE MID TO UPPER 20S NORTH AND LOWER 30S DOWNEAST. THE COLD FRONT WILL CROSS NORTHERN AREAS SATURDAY NIGHT AND THEN STALL IN THE VICINITY OF THE COAST SUNDAY. EXPECT A FEW SNOW SHOWERS ACROSS NORTHERN AREAS SATURDAY NIGHT WITH THE PASSAGE OF THE FRONT WITH DRY CONDITIONS DOWNEAST. LOWS SATURDAY NIGHT WILL GENERALLY RANGE FROM THE MID TEENS NORTH AND LOW TO MID 20 CENTRAL AND DOWN EAST. LOW PRESSURE WILL APPROACH FROM THE WEST SUNDAY WITH THE FRONT STARTING TO MOVE BACK TO THE NORTH AS A WARM FRONT. EXPECT SNOW TO DEVELOP ACROSS THE NORTH AND WEST LATER SUNDAY AFTERNOON WITH MAYBE AN INCH OR SO BY LATE SUNDAY AFTERNOON. ACROSS DOWNEAST AREAS EXPECT MAINLY CLOUDY SKIES. THERE WILL BE QUITE THE TEMPERATURE GRADIENT ON SUNDAY WITH HIGHS ACROSS THE NORTH MAINLY IN THE LOW TO MID 20S BUT IN THE MID 30S TO AROUND 40 ACROSS CENTRAL AND DOWNEAST. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... LOW PRESSURE WILL CONTINUE TO TRACK EAST TOWARD THE AREA SUNDAY NIGHT. A TIGHT THERMAL GRADIENT IN ASSOCIATION WITH A STRONG BAROCLINIC ZONE WILL SET UP ACROSS NORTHERN MOST MAINE SUPPORTING OVERRUNNING PRECIPITATION, MAINLY IN THE FORM OF SNOW ACROSS FAR NORTHERN MAINE. THE PRECIPITATION WILL CONTINUE INTO MONDAY BEFORE TAPERING TO SNOW SHOWERS LATER MONDAY AFTERNOON AS THE LOW TRACKS ACROSS TEH CANADIAN MARITIMES. THERE COULD BE SEVERAL INCHES OF SNOW ACROSS NORTHERN AREAS, ESPECIALLY THE SAINT JOHN VALLEY SUNDAY NIGHT AND INTO MONDAY. ACROSS CENTRAL AND DOWNEAST AREAS EXPECT MAINLY CLOUDY SKIES WITH THE CHANCE FOR RAIN SHOWERS. COLDER AIR WILL MOVE IN MONDAY NIGHT IN THE WAKE OF THE LOW WITH A FEW LINGERING SNOW SHOWERS POSSIBLE ACROSS NORTHERN AREAS AND PARTLY CLOUDY SKIES DOWNEAST. HIGH PRESSURE WILL BUILD EAST TOWARD THE AREA TUESDAY AND TUESDAY NIGHT. ANOTHER LOW PRESSURE SYSTEM WILL TRACK TOWARD THE AREA BY MID TO LATE WEEK BRINGING SOME SNOW OR EVEN RAIN TO THE REGION DEPENDING ON THE EXACT TRACK OF THE SYSTEM. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... NEAR TERM: MVFR FRO THE NORTHERN TERMINALS TODAY W/A TEMPO OF IFR THIS MORNING DUE TO SNOW. KBGR AND KBHB WILL SEE VFR FOR THE MOST PART TODAY W/A BRIEF PERIOD OF MVFR THIS MORNING. LOOK FOR IMPROVING CONDITIONS TONIGHT W/VFR FOR ALL TERMINALS. SHORT TERM: VFR SATURDAY ALL TERMINALS. MVFR IS POSSIBLE SATURDAY NIGHT AT THE NORTHERN TERMINALS IN SCT SNOW SHOWERS WITH VFR KBGR/KBHB. VFR THRU MUCH OF SUNDAY. IFR/LIFR CAN BE EXPECTED SUNDAY NIGHT AT THE NORTHERN TERMINALS IN SNOW WITH CONTINUED VFR KBGR/KBHB. THESE CONDITIONS WILL PERSIST INTO MONDAY. VFR RETURNS ALL TERMINALS MONDAY NIGHT THROUGH TUESDAY. && .MARINE... NEAR TERM: TRANSITIONED THE GALE WARNING TO A SCA INTO TONIGHT. WINDS HAVE DROPPED BACK TO 25 KTS W/SOME GUSTS TO 30 KT. A SURGE IN THE WINDS POSSIBLE LATER TODAY AS CAA HITS THE WARMER WATERS. SEAS ARE RUNNING 10-13 FT W/A SWELL COMPONENT FROM THE SE. PERIODS OF 11-12 SECONDS OUT THERE ATTM. THE SEA STATE WILL SUBSIDE TONIGHT AS THE WIND COMPONENT GOES OFFSHORE. SHORT TERM: A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED SATURDAY NIGHT AND SUNDAY. WINDS/SEAS ARE LIKELY TO CONTINUE AT SMALL CRAFT ADVISORY CONDITIONS THROUGH EARLY NEXT WEEK. && .HYDROLOGY... THE FLOOD WATCH REMAINS IN PLACE. SNOW FALLING AS COLDER AIR MOVING INTO THE REGION. THIS WILL BEGIN TO SLOW THINGS UP TODAY. RIVERS/STREAMS ARE HIGH W/SOME ICE MOVEMENT ESPECIALLY ON THE KINGSBURY STREAM IN PISCATAQUIS COUNTY. THREAT FOR MINOR FLOODING INCLUDING ICE JAM FLOODING IS STILL POSSIBLE ON THE SAINT JOHN...AROOSTOOK...PISCATAQUIS AND ALLAGASH RIVERS ALONG WITH SMALLER STREAMS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...FLOOD WATCH UNTIL NOON EST TODAY FOR MEZ001>006-010-031. MARINE...SMALL CRAFT ADVISORY UNTIL 3 AM EST SATURDAY FOR ANZ050>052. && $$ NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
137 PM PST FRI FEB 26 2016 .SYNOPSIS... WEAK ONSHORE FLOW WILL CREATE SLIGHTLY COOLER WEATHER IN THE COAST AND VALLEYS AND SOME WARMING FOR THE MOUNTAINS AND DESERTS THROUGH THE WEEKEND...WITH NIGHT AND MORNING COASTAL LOW CLOUDS AND FOG POSSIBLE. ANOTHER WARM-UP EXPECTED MONDAY THROUGH TUESDAY DUE TO STRENGTHENING HIGH PRESSURE ALOFT...WITH WEAK OFFSHORE FLOW CREATING WARMING ALL THE WAY TO THE COAST. WEAK ONSHORE FLOW WEDNESDAY BRINGS SOME COOLING TO THE COAST AND VALLEYS BUT SOME WARMING IN THE MOUNTAINS AND DESERTS. COOLER IN ALL AREAS ON THURSDAY AS A TROUGH MOVING INTO CENTRAL CALIFORNIA BRINGS STRENGTHENING ONSHORE FLOW AND A DEEPENING OF THE MARINE LAYER. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... AFTERNOON VISIBLE SATELLITE SHOWS BANDS OF HIGH CLOUDS MOVING OVER THE REGION FROM THE WEST. WATER VAPOR SATELLITE INDICATES A WEAK RIDGE ALOFT OVER SOUTHERN CALIFORNIA...AND A TROUGH APPROACHING THE WEST COAST. PRESSURE GRADIENTS SHOW THAT WE ARE TRENDING TOWARDS ONSHORE FLOW...AS THE SAN DIEGO TO LAS VEGAS GRADIENT IS CURRENTLY ONLY 0.4 MB ONSHORE...WHEREAS IT WAS 2.3 MB OFFSHORE AT THIS TIME YESTERDAY. WITH A BETTER SEA BREEZE KICKING IN AND THE RIDGE ALOFT WEAKENING A BIT TODAY...TEMPERATURES IN THE COAST AND VALLEYS AT 1 PM ARE A FEW TO SEVERAL DEGREES LOWER THAN AT 1 PM YESTERDAY...WHILE THEY ARE A FEW TO SEVERAL DEGREES HIGHER IN THE MOUNTAINS AND DESERTS. WITH THE TRENDING ONSHORE FLOW AND VERY SHALLOW MARINE LAYER...LOCAL WRF AND HRRR ARE INDICATING POSSIBLE DENSE FOG FORMATION ABOUT 5 TO LOCALLY 10 MILES INLAND FROM THE COAST TONIGHT THROUGH EARLY SATURDAY MORNING. IT IS POSSIBLE THAT THE HIGH CLOUDS MOVING IN COULD DISRUPT THE FORMATION OF FOG SOMEWHAT...BUT THE HIGH CLOUDS DO NOT LOOK TO BE THICK ENOUGH TO PREVENT FOG FORMATION ALTOGETHER. A SHORT-WAVE TROUGH WILL MOVE INTO THE PACIFIC NORTHWEST ON SATURDAY...NUDGING THE RIDGE ALOFT FURTHER SOUTH AND BRINGING PREVAILING WEAK ONSHORE FLOW. THIS SHOULD CREATE A LITTLE MORE COOLING FOR THE COAST AND VALLEYS...WHILE THE MOUNTAINS AND DESERTS ACTUALLY GET A LITTLE WARMER. TEMPERATURES ON SUNDAY LIKELY PRETTY SIMILAR TO SATURDAY. A CONTINUED SHALLOW MARINE LAYER MAY RESULT IN MORE FOG/LOW CLOUDS SATURDAY NIGHT/SUNDAY MORNING. LOW CLOUDS/FOG MAY MOVE A LITTLE FARTHER INLAND SUNDAY NIGHT/MONDAY MORNING DUE TO MOMENTARILY INCREASING ONSHORE FLOW AND DECREASING 500 MB HEIGHTS AS A TROUGH MOVES INTO THE GREAT BASIN. MODELS SHOW THE RIDGE RE-BUILDING OVER SOUTHERN CALIFORNIA MONDAY AFTERNOON THROUGH TUESDAY WHICH WILL CREATE ANOTHER WARMING TREND...WITH HIGHS ONCE AGAIN REACHING 10-20 DEGREES ABOVE NORMAL. WEAK OFFSHORE FLOW MONDAY AFTERNOON THROUGH TUESDAY WILL HELP BRING THE WARMING ALL THE WAY TO THE COAST ON THOSE DAYS...THEN ONSHORE FLOW ON WEDNESDAY STARTS TO BRING SOME COOLING TO THE COAST. A COOL-DOWN IS EXPECTED THURSDAY AS A TROUGH MOVES INTO CENTRAL CALIFORNIA AND ONSHORE FLOW STRENGTHENS. THIS SHOULD PRODUCE A DEEPER MARINE LAYER AS WELL. HOWEVER...MODELS CONTINUE TO KEEP ANY PRECIPITATION TO OUR NORTH. && .AVIATION... 262100Z...FAIR SKIES WITH SOME HIGH CLOUDS AND UNRESTRICTED VIS ARE EXPECTED THROUGH SATURDAY AFTERNOON ACROSS THE REGION. NEAR THE COAST AFTER 03Z AREAS OF LOW CLOUDS AND FOG WILL DEVELOP AND MOVE A SHORT DISTANCE ONSHORE AND BECOME A MORE UNIFORM DECK AFTER 08Z. CIGS WILL BE AROUND 400-700 FEET MSL WITH TOPS TO 1200 FEET. IN GENERAL VIS WILL BE 1-4SM AT THE COAST...BUT LOCALLY AS LOW AS 1/4SM MAINLY ON COASTAL MESAS AND ALONG THE INLAND EXTENT OF FOG. LOW CLOUDS AND FOG SHOULD LIFT AND SCATTER OUT BY 16-17Z SATURDAY. && .MARINE... 100 PM...AREAS OF FOG WITH VIS 1NM OR LESS ARE EXPECTED TONIGHT. A LARGE WEST-NORTHWEST SWELL WITH A LONG PERIOD WILL ARRIVE TONIGHT AND PRODUCE COMBINED SEAS UP TO 10 FEET MAINLY SOUTH OF SAN CLEMENTE ISLAND SATURDAY THROUGH SUNDAY MORNING. OTHERWISE...NO ADDITIONAL MARINE WEATHER HAZARDS ARE EXPECTED THROUGH WEDNESDAY. && .BEACHES... 100 PM...A BUILDING SWELL WILL PRODUCE HIGH SURF TONIGHT THROUGH SUNDAY. THE HIGHEST SURF WILL PEAK SATURDAY AFTERNOON AND EVENING BEFORE GRADUALLY DECREASING SUNDAY. FOR SURF AND HAZARD DETAILS...CHECK THE SURF FORECAST LAXSRFSGX...AND THE HIGH SURF ADVISORY LAXCFWSGX. && .SKYWARN... SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...HIGH SURF ADVISORY UNTIL 9 PM PST SUNDAY FOR ORANGE COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS. PZ...NONE. && $$ PUBLIC...HARRISON AVIATION/MARINE/BEACHES...MM
AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
915 AM PST FRI FEB 26 2016 .SYNOPSIS... THIS WEEKEND THE ONSHORE FLOW WILL ALLOW OVERNIGHT LOW CLOUDS AND FOG TO FORM ALONG THE COAST WITH TEMPERATURES SLIGHTLY COOLER EVERYWHERE. A HIGH WILL BUILD IN NEXT WEEK FOR A WARMING TREND AND DECREASING CLOUDINESS INTO MIDWEEK. BUT A LOW WILL DIP SOUTH ON THURSDAY FOR INCREASING CLOUDINESS AND POSSIBLE PRECIPITATION NORTH OF SANTA BARBARA. && .SHORT TERM...(TDY-SUN) GRADIENTS TRENDING ONSHORE TODAY AS A WEAK COLD FRONT APPROACHES CALIFORNIA FROM THE WEST. A SHALLOW MARINE LAYER HAS FORMED WITH SOME DENSE FOG REPORTED ALONG THE COAST NORTH OF VENTURA. TEMPERATURES OFF TO A SLOWER START NEAR THE COAST THIS MORNING WITH THE MARINE INFLUENCE SO THE COOLING TREND IN THE FORECAST LOOKS GOOD. MAY SEE LOW CLOUDS LINGERING ALONG THE CENTRAL COAST THROUGH THE DAY WITH THE FRONT LINGERING OFFSHORE SO FORECAST CLEARING THERE MAY BE A BIT OPTIMISTIC, ESPECIALLY AT THE BEACHES. ***FROM PREVIOUS DISCUSSION*** THE REMNANTS OF THE WEAK COLD FRONT ASSOC WITH TODAYS TROF WILL MOVE OVER THE AREA TONIGHT. IT WILL NOT DO TOO MUCH EXCEPT USHER IN A BURST OF NORTH WINDS. THE NORTH WINDS WILL SPIN A WEAK EDDY UP WHICH WILL BRING SOME LOW CLOUDS TO THE LA COAST AND THE THE WESTERN PORTION OF SBA COUNTY (ALTHOUGH THERE IS A FAIR CHANCE THAT THE ATMOSPHERE WILL BE TOO WELL MIXED FOR THE CLOUDS TO FORM). THE NORTH FLOW WILL ALSO PUSH SOME CLOUDS UP THE NORTH SLOPES. THERE WILL BE SUB ADVISORY WIND GUSTS THROUGH THE I-5 CORRIDOR AND SBA SOUTH COAST. SATURDAY WILL BE THE COOLEST DAY WITH THE LOWEST HGTS AND THE STRONGEST ONSHORE FLOW TOWARDS KDAG (STILL OFFSHORE FROM KBFL) MORE RIDGING AND MORE NORTH FLOW ON TAP FOR SUNDAY. THERE WILL AGAIN BE SOME SUB ADVISORY LEVEL NORTH WINDS (NO UPPER OR THERMAL SUPPORT) THESE WINDS WILL NOT BE STRONG ENOUGH TO SCOUR OUT THE LOW CLOUDS FROM THE LA COAST. IT WILL BE PARTLY CLOUDY AS SOME MID LEVEL CLOUDS MOVE IN THE WESTERLY FLOW ALOFT. MAX TEMPS WILL BEGIN TO RISE. .LONG TERM...(MON-THU) EARLY MONDAY THE RIDGE AND THE NORTHERLY FLOW INCREASES. THE NORTH PUSH MAY BE STRONG ENOUGH TO CREATE A LOW END WIND ADVISORY THROUGH THE I-5 CORRIDOR AND THE SBA SOUTH COAST. THE WARMING TREND WILL CONTINUE AND THERE WILL BE BROAD SWATH OF 80S ACROSS MUCH OF THE COASTS AND VLYS. ON TUESDAY THE RIDGING PEAKS AND THE OFFSHORE FLOW TRANSITIONS TO THE NE. SANTA ANA WINDS WILL CARRY THE DAY. MAX TEMPS WILL BUMP UP A FEW MORE DEGREES. WEDNESDAY WILL BE LIKE TUESDAY JUST A LITTLE LESS SO. THE RIDGE AND THE OFFSHORE FLOW WILL BE WEAKER. SKIES WILL TURN PARTLY CLOUDY AS MID AND HIGH LEVEL CLOUDS STREAM IN. MAX TEMPS WILL REMAIN WELL ABOVE NORMAL JUST A FEW DEGREES COOLER THAN TUESDAY. A FAST MOVING TROF AND COLD FRONT WILL ZOOM INTO THE AREA THURSDAY. HGTS WILL FALL AND THE OFFSHORE FLOW WILL REVERSE. SKIES WILL BE PARTLY CLOUDY SOUTH OF POINT CONCEPTION AND WILL TURN MOSTLY CLOUDY NORTH OF POINT CONCEPTION. A SLIGHT CHC OF LIGHT RAIN WILL DEVELOP OVER SLO AND SBA COUNTIES DURING THE AFTERNOON. MAX TEMPS WILL FALL 5 TO 10 DEGREES FROM WEDNESDAYS READINGS. && .AVIATION...26/1200Z AT 0920Z...THE MARINE LAYER DEPTH AT KLAX WAS AROUND 500 FEET. THE TOP OF THE MARINE INVERSION WAS AROUND 1900 FEET WITH A TEMPERATURE OF 21 DEGREES CELSIUS. STRATUS AND FOG...WITH LIFR TO VLIFR CIGS AND VSBYS WILL AFFECT THE CENTRAL COAST THROUGH MID MORNING. THERE IS A SLIGHT CHANCE OF STRATUS WITH LIFR CONDS AFFECTING COASTAL SECTIONS OF WRN L.A. COUNTY...VTU AND SERN SBA COUNTY THROUGH MID MORNING. OTHERWISE...VFR CONDS THROUGH THIS EVENING...WITH PLENTY OF HIGH CLOUDS. TONIGHT...EXPECT STRATUS WITH LIFR TO VLIFR CONDS AFTER MIDNIGHT ACROSS COASTAL SECTIONS OF L.A. COUNTY AND THE CENTRAL COAST...AND POSSIBLY ACROSS COASTAL SECTIONS OF VTU COUNTY. SOME LLWS IS EXPECTED NEAR KSBA AS GUSTY NLY WINDS DEVELOP THROUGH AND BELOW PASSES AND CANYONS OF THE SANTA YNEZ RANGE. KLAX...MODERATE CONFIDENCE IN THE 12Z TAF. THERE IS A 10 TO 20 PERCENT CHC OF VLIFR CIGS AND VIS BETWEEN 14Z AND 16Z THIS MORNING. EXPECT VLIFR CONDS AFTER 09Z TONIGHT. THESE IS A 20 PERCENT CHANCE VLIFR CONDS COULD OCCUR AS EARLY AS 05Z. THERE IS A 20 PERCENT CHANCE THAT CONDS WILL REMAIN VFR TONIGHT/SAT MORNING. KBUR...HIGH CONFIDENCE IN THE 12Z TAF WITH VFR CONDS EXPECTED THROUGH THE PD. && .MARINE...26/300 AM. GOOD CONFIDENCE IN SCA CONDS ACROSS THE OUTER WATERS THROUGH SUN NIGHT. FOR TODAY...WINDS MAY BE BELOW SCA LEVELS IN SOME AREAS...BUT SEAS SHOULD BE AT OR ABOVE 10 FEET...AT LEAST IN MOST AREAS. EXPECT MORE WIDESPREAD SCA LEVEL WINDS ACROSS THE OUTER WATERS TONIGHT THROUGH SUN NIGHT...WITH SEAS AT OR ABOVE 10 FEET. EXPECT 10 FOOT SEAS TO REACH THE NORTHERN INNER WATER LATE IN THE DAY. ACROSS THE NRN INNER WATERS...THERE IS A 30 PERCENT CHANCE THAT WINDS WILL REMAIN BELOW SCA LEVELS ACROSS THE NRN INNER WATERS UNTIL SAT AFTERNOON...BUT GOOD CONFIDENCE THAT SEAS WILL BE ABOVE THRESHOLDS. MODERATELY LARGE SWELL WILL AFFECT THE SOUTHERN INNER WATERS AND THE SANTA BARBARA CHANNEL SAT THROUGH SUN...BUT SHOULD REMAIN BELOW SCA LEVELS. && .BEACHES...25/900 PM. HIGH SURF HAS BEEN EXTENDED INTO AT LEAST SUNDAY AS A WEST- NORTHWEST SWELL CURRENTLY IN THE EAST CENTRAL PACIFIC IS EXPECTED TO BUILD OVER THE WATERS FRIDAY THROUGH SATURDAY. HIGH SURF ADVISORY CONDITIONS WILL LIKELY EXIST ALONG ALL EXPOSED WEST AND NORTHWEST FACING SHORES FRIDAY NIGHT THROUGH SUNDAY. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...HIGH SURF ADVISORY IN EFFECT UNTIL 9 AM PST SUNDAY FOR ZONES 34-35. (SEE LAXCFWLOX). BEACH HAZARDS STATEMENT IN EFFECT THROUGH SUNDAY EVENING FOR ZONE 39. (SEE LAXCFWLOX). HIGH SURF ADVISORY IN EFFECT UNTIL 9 PM PST SUNDAY FOR ZONES 40-41-87. (SEE LAXCFWLOX). PZ...SMALL CRAFT ADVISORY IN EFFECT FROM 3 PM THIS AFTERNOON TO 3 AM PST MONDAY FOR ZONE 645. (SEE LAXMWWLOX). SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 AM PST MONDAY FOR ZONES 670-673-676. (SEE LAXMWWLOX). && $$ PUBLIC...MW AVIATION...BRUNO MARINE...BRUNO BEACHES...HALL SYNOPSIS...SETO WEATHER.GOV/LOSANGELES
  [top] Area Forecast Discussion National Weather Service Sacramento CA 914 AM PST FRI FEB 26 2016 .SYNOPSIS...DRY WEATHER WITH ABOVE NORMAL TEMPERATURES THIS AFTERNOON. A WEAK SYSTEM WILL BRING A CHANCE FOR LIGHT RAIN, MAINLY NORTH OF INTERSTATE 80 THIS EVENING INTO EARLY SATURDAY... FOLLOWED BY AN EVEN WEAKER SYSTEM SUNDAY INTO MONDAY MORNING. && .DISCUSSION... Frontal boundary and upper trof just off the N Coast this morning and poised to move across Norcal mainly during the evening time frame. Only change contemplated in the short term is the potential for a thunderstorm or two over Shasta Co with FROPA and upper trof passage. CAPE/instability progs suggesting the area from Shasta Co into NErn Tehama/Wrn Plumas Co will have the potential for convection during the evening. Forecast soundings indicate potential for elevated instability with the high resolution QPF/REF progs highlighting the Shasta Co area. Any thunder that occurs should be brief/isolated and should move quickly with the progressive nature of the trof. In general...this system will weaken as it encounters the W Coast ridge and moves over Norcal. This system and the Sun/Mon system should have limited impacts. JHM Daytime highs this afternoon will be a few degrees cooler than yesterday, but still several degrees above normal. Models in fairly good agreement that a weak trough will move inland this evening. The current HRRR shows precipitation moving into our CWA after 4 pm. The bulk of precipitation from this system continues to track north of I- 80. The Sacramento region will likely only see a few hundredths of an inch while locations south of I-80 (Stockton- Modesto area) will probably stay dry or just see trace amounts of rain. Valley areas north of I-80 should range 0.05-0.25" with the higher amounts near Red Bluff and Redding. Mountain rain amounts will range 0.10" up to around a half inch with the Shasta County mountains and Lassen Peak having the highest amounts. Snow levels will stay above pass levels today and then lower overnight between 5500-6500 ft north of I-80 by early Saturday morning. However, any snow amounts that occur will be very light...a dusting up to around an inch or two at the higher peaks. Sierra travel on I-80 and Hwy 50 should see very minimal impacts, if any. Precipitation should end by late morning on Saturday giving way to another dry and warm afternoon/night. The next weak system is forecast to move across NorCal on Sunday with light rain hitting the coastal range and northern Sacramento Valley by late Sunday morning. Precipitation will then spread southward towards the I-80 corridor by Sunday afternoon into early Monday morning. Rain amounts will be lighter than the Fri-Sat system and, once again, snow will be an inch at best for the higher elevations north of I-80. Ridging re-develops over NorCal Monday into Tuesday. JBB && .EXTENDED DISCUSSION (Tuesday THROUGH Friday) Generally dry and mild weather is expected through the first half of next week. A weak system will pass over far Northern California Tuesday with light showers possible. Otherwise, temperatures are likely to peak on Wednesday, with highs roughly 5 to 10 degrees above normal. Models continue to indicate a stronger trough moving through around Thursday of next week. While not a strong system, this will likely be the first shot at region-wide precipitation in the next week. && && .AVIATION... Mainly VFR conditions the next 24 hours, except MVFR conditions in BR in the northern San Joaquin Valley through about 17z. A weather system may bring local MVFR conditions over the mountains tonight into early Saturday. Breezy southwest winds over higher terrain this afternoon through tonight. Dang && .STO Watches/Warnings/Advisories... None. && $$
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
840 AM PST FRI FEB 26 2016 .SYNOPSIS... WEAK ONSHORE FLOW WILL CREATE SLIGHTLY COOLER WEATHER IN THE COAST AND VALLEYS AND SOME WARMING FOR THE MOUNTAINS AND DESERTS THROUGH THE WEEKEND...WITH NIGHT AND MORNING COASTAL LOW CLOUDS AND FOG POSSIBLE. ANOTHER WARM-UP EXPECTED MONDAY THROUGH WEDNESDAY DUE TO STRENGTHENING HIGH PRESSURE ALOFT...WITH WEAK OFFSHORE FLOW MONDAY AND TUESDAY CREATING WARMING ALL THE WAY TO THE COAST...WHILE WEAK ONSHORE FLOW WEDNESDAY BRINGS SOME COOLING TO THE COAST. COOLER IN ALL AREAS ON THURSDAY AS A TROUGH MOVING INTO CENTRAL CALIFORNIA BRINGS STRENGTHENING ONSHORE FLOW AND A DEEPENING OF THE MARINE LAYER. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... MORNING VISIBLE SATELLITE SHOWS SOME PATCHES OF FOG OVER THE COASTAL WATERS...WITH A FEW BANDS OF HIGH CLOUDS MOVING IN FROM THE WEST. WATER VAPOR SATELLITE INDICATES A WEAK RIDGE ALOFT OVER SOUTHERN CALIFORNIA...AND A TROUGH APPROACHING THE WEST COAST. PRESSURE GRADIENTS SHOW THAT WE ARE TRENDING TOWARDS ONSHORE FLOW...AS THE SAN DIEGO TO LAS VEGAS GRADIENT IS CURRENTLY ONLY 1.0 MB OFFSHORE...WHEREAS IT WAS 2.9 MB OFFSHORE AT THIS TIME YESTERDAY. WITH A BETTER SEA BREEZE KICKING IN AND THE RIDGE ALOFT WEAKENING A BIT TODAY...EXPECT HIGHS IN THE COAST AND VALLEY SECTIONS TO BE A FEW DEGREES LOWER THAN YESTERDAY...WHILE THE MOUNTAINS AND DESERTS ARE SEVERAL DEGREES HIGHER. WITH THE TRENDING ONSHORE FLOW AND VERY SHALLOW MARINE LAYER...LOCAL WRF AND HRRR ARE INDICATING POSSIBLE DENSE FOG FORMATION ABOUT 5 TO LOCALLY 10 MILES INLAND FROM THE COAST TONIGHT THROUGH EARLY SATURDAY MORNING. IT IS POSSIBLE THAT THE HIGH CLOUDS MOVING IN COULD DISRUPT THE FORMATION OF FOG SOMEWHAT...BUT THE HIGH CLOUDS DO NOT LOOK TO BE THICK ENOUGH TO PREVENT FOG FORMATION ALTOGETHER. A SHORT-WAVE TROUGH WILL MOVE INTO THE PACIFIC NORTHWEST ON SATURDAY...NUDGING THE RIDGE ALOFT FURTHER SOUTH AND BRINGING PREVAILING WEAK ONSHORE FLOW. THIS SHOULD CREATE FURTHER COOLING FOR THE COAST AND VALLEYS...WHILE THE MOUNTAINS AND DESERTS ACTUALLY GET A LITTLE WARMER. TEMPERATURES ON SUNDAY LIKELY PRETTY SIMILAR TO SATURDAY. A CONTINUED SHALLOW MARINE LAYER MAY RESULT IN MORE FOG/LOW CLOUDS SATURDAY NIGHT/SUNDAY MORNING. LOW CLOUDS/FOG MAY MOVE A LITTLE FARTHER INLAND SUNDAY NIGHT/MONDAY MORNING DUE TO MOMENTARILY INCREASING ONSHORE FLOW AND DECREASING 500 MB HEIGHTS AS A TROUGH MOVES INTO THE GREAT BASIN. MODELS SHOW THE RIDGE RE-BUILDING OVER SOUTHERN CALIFORNIA MONDAY AFTERNOON THROUGH WEDNESDAY WHICH WILL CREATE ANOTHER WARMING TREND...WITH HIGHS ONCE AGAIN REACHING 10-20 DEGREES ABOVE NORMAL. WEAK OFFSHORE FLOW MONDAY AFTERNOON THROUGH TUESDAY WILL HELP BRING THE WARMING ALL THE WAY TO THE COAST ON THOSE DAYS...WITH ONSHORE FLOW ON WEDNESDAY STARTING TO BRING SOME COOLING TO THE COAST. A COOL-DOWN IS EXPECTED THURSDAY AS A TROUGH MOVES INTO CENTRAL CALIFORNIA AND ONSHORE FLOW STRENGTHENS. THIS SHOULD PRODUCE A DEEPER MARINE LAYER AS WELL. HOWEVER...MODELS CONTINUE TO KEEP ANY PRECIPITATION TO OUR NORTH. && .AVIATION... 261630Z...FAIR SKIES WITH SOME HIGH CLOUDS AND UNRESTRICTED VIS ARE EXPECTED TODAY INTO SATURDAY MORNING ACROSS THE REGION. NEAR THE COAST AFTER 03Z AREAS OF LOW CLOUDS AND FOG WILL DEVELOP AND MOVE A SHORT DISTANCE ONSHORE AND BECOME A MORE UNIFORM DECK AFTER 08Z. CIGS WILL BE AROUND 400-700 FEET MSL WITH TOPS TO 1200 FEET. IN GENERAL VIS WILL BE 2-5SM AT THE COAST...BUT LOCALLY BELOW 1SM MAINLY ALONG COASTAL MESAS AND INLAND EXTENT OF FOG. LOW CLOUDS AND FOG SHOULD LIFT AND SCATTER OUT BY 16-17Z SATURDAY. && .MARINE... 830 AM...PATCHES OF FOG WITH VIS 1NM OR LESS ARE POSSIBLE TODAY AND TONIGHT. A LARGE WEST-NORTHWEST SWELL WITH A LONG PERIOD WILL ARRIVE TONIGHT AND PRODUCE COMBINED SEAS OF 8-10 FEET MAINLY SOUTH OF SAN CLEMENTE ISLAND SATURDAY THROUGH SUNDAY MORNING. OTHERWISE...NO ADDITIONAL MARINE WEATHER HAZARDS ARE EXPECTED THROUGH TUESDAY. && .BEACHES... 830 AM...A BUILDING SWELL WILL PRODUCE HIGH SURF TONIGHT THROUGH SUNDAY. THE HIGHEST SURF WILL PEAK SATURDAY AFTERNOON BEFORE GRADUALLY DECREASING SUNDAY. FOR SURF AND HAZARD DETAILS...CHECK THE SURF FORECAST LAXSRFSGX...AND THE HIGH SURF ADVISORY LAXCFWSGX. && .SKYWARN... SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...HIGH SURF ADVISORY UNTIL 9 PM PST SUNDAY FOR ORANGE COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS. PZ...NONE. && $$ PUBLIC...HARRISON AVIATION/MARINE/BEACHES...MM
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
309 PM CST FRI FEB 26 2016 .SHORT TERM...(Tonight) ISSUED AT 309 PM CST FRI FEB 26 2016 Earlier clearing over the southeast half of the CWA has filled in since late morning. However, back edge of the low cloud shield has moved into west central Illinois this afternoon. Latest RAP guidance suggests most of this should be out of the CWA by mid evening, with a period of clear skies. However, an area of cirrus will move through after midnight, associated with the upper wave currently seen on water vapor imagery from the west tip of Lake Superior into western Kansas. This will result in partly cloudy conditions as the wave zips through overnight. Will need to watch for some fog potential over east central Illinois, as there were 1-3 inches of snow on the ground there this morning and some melting has taken place. However, winds will be picking up after midnight, which may help mitigate the threat. Currently, only the SREF is indicating any visibility restrictions overnight. Will leave out mention for now and continue to monitor. && .LONG TERM...(Saturday through Friday) ISSUED AT 309 PM CST FRI FEB 26 2016 Any patchy early morning fog in east-central Illinois early Saturday morning should quickly dissipate as southwest winds crank up into the 15 to 25 mph range. The gusty winds and ample sunshine will go a long way toward melting any remaining snow pack in our counties as well, with high temps expected to reach in the 50s across the board. The upper level ridge responsible for the warming trend will begin to shift east of Illinois on Sunday, as the next in a series of low pressure systems approaches the Great Lakes region. Despite increasing afternoon clouds and slight chances of rain north of Springfield to Mattoon on Sunday, strong south to southwest winds of 25 to 35 mph will provide our warmest day of the next week. Highs will climb into the low to mid 60s. Thunder potential appears to have lowered with the latest model suite, so no mention of thunder was included ahead of the cold front later Sunday afternoon. Slight chances of rain will linger into Sunday evening east of I-57, with dry conditions after midnight when the cold front departs well to the east. A brief push of cooler air will arrive for Monday, but plenty of sunshine will help high temps recover into the 50s, which are still well above normal. The extended models once again have come in with widely varying solutions. The ECMWF is the only model to develop a deep 990mb low passing across Illinois roughly along I-72 on Tuesday. It indicates enough cold air N-NW of the low for several inches of snow W of I-55 Tue afternoon, with rain changing to snow east of I-55 into the evening. A few thunderstorms would even be possible south of I-72 on Tuesday. The GFS has a weak and more elongated surface low develop and pass by to the south of Illinois on Tuesday, with precip mainly south of I-72, and mainly rain until colder air arrives Tuesday evening and changes rain to snow as precip ends. The Canadian GEM has more of an open wave and surface trough pass across Illinois on Tuesday, with precip starting briefly as rain early Tuesday then changing to snow, with light accums possible. With such large swings in each models solutions from cycle to cycle, along with differences between the models, only minor changes were made to the forecast from late Monday night through Tues night. The blended initialization shifted the Likely PoPs on Tuesday to areas southeast of Decatur, with high chance PoPs elsewhere in central Illinois. The actual PoP numbers were relatively close to the previous forecast in general. Precip type scenarios were tied to a warm surge on Tuesday, then rain changing to snow from W to E Tues night, as colder air arrives behind the low/surface trough. Changes to this scenario are likely over the next couple of days before models start to converge on a solution. A break in the precip chances is expected for Wednesday as weak high pressure passes across IL. However, another upper level shortwave and surface trough are projected to pass over Illinois on Thursday. There will be higher chances of rain or snow southeast of the Illinois river, closer to the track of the upper vort max and jet dynamics. High temps will dip back below normal from Wednesday to Friday as the waves bring brief shots of cooler air to the region. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) ISSUED AT 1128 AM CST FRI FEB 26 2016 Ceilings are falling just below 3000 feet late this morning from KSPI-KCMI as a stratocumulus deck spreads southeast. Am expecting some modest improvement in heights by mid afternoon back into VFR range. The overall cloud deck will continue to push east, and should be out of the TAF sites by mid evening. Continue to have some concerns regarding fog potential overnight across east central Illinois, where snow is currently melting. SREF visibility probabilities showing 30-40% chance of 1 mile visibility between 09-12Z in this area, where the snow is thickest. A couple things that may help mitigate it are an increasing southerly wind which will set up after 06Z, as well as some higher clouds accompanying an upper level trough. Right now, will continue with prevailing MVFR visibilities at KCMI late tonight, with TEMPO periods at KBMI/KDEC where there is less snow cover. Any fog should burn off by 15Z with sunshine and winds increasing to around 10 knots. && .ILX Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Geelhart LONG TERM...Shimon AVIATION...Geelhart
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
308 PM CST FRI FEB 26 2016 .SHORT TERM...(Tonight) ISSUED AT 308 PM CST FRI FEB 26 2016 Earlier clearing over the southeast half of the CWA has filled in since late morning. However, back edge of the low cloud shield has moved into west central Illinois this afternoon. Latest RAP guidance suggests most of this should be out of the CWA by mid evening, with a period of clear skies. However, an area of cirrus will move through after midnight, associated with the upper wave currently seen on water vapor imagery from the west tip of Lake Superior into western Kansas. This will result in partly cloudy conditions as the wave zips through overnight. Will need to watch for some fog potential over east central Illinois, as there were 1-3 inches of snow on the ground there this morning and some melting has taken place. However, winds will be picking up after midnight, which may help mitigate the threat. Currently, only the SREF is indicating any visibility restrictions overnight. Will leave out mention for now and continue to monitor. && .LONG TERM...(Saturday through Friday) ISSUED AT 308 PM CST FRI FEB 26 2016 Any patchy early morning for in east-central Illinois early Saturday morning should quickly dissipate as southwest winds crank up into the 15 to 25 mph range. The gusty winds and ample sunshine will go a long way toward melting any remaining snow pack in our counties as well, with high temps expected to reach in the 50s across the board. The upper level ridge responsible for the warming trend will begin to shift east of Illinois on Sunday, as the next in a series of low pressure systems approaches the Great Lakes region. Despite increasing afternoon clouds and slight chances of rain north of Springfield to Mattoon on Sunday, strong south to southwest winds of 25 to 35 mph will provide our warmest day of the next week. Highs will climb into the low to mid 60s. Thunder potential appears to have lowered with the latest model suite, so no mention of thunder was included ahead of the cold front later Sunday afternoon. Slight chances of rain will linger into Sunday evening east of I-57, with dry conditions after midnight when the cold front departs well to the east. A brief push of cooler air will arrive for Monday, but plenty of sunshine will help high temps recover into the 50s, which are still well above normal. The extended models once again have come in with widely varying solutions. The ECMWF is the only model to develop a deep 990mb low passing across Illinois roughly along I-72 on Tuesday. It indicates enough cold air N-NW of the low for several inches of snow W of I-55 Tue afternoon, with rain changing to snow east of I-55 into the evening. A few thunderstorms would even be possible south of I-72 on Tuesday. The GFS has a weak and more elongated surface low develop and pass by to the south of Illinois on Tuesday, with precip mainly south of I-72, and mainly rain until colder air arrives Tuesday evening and changes rain to snow as precip ends. The Canadian GEM has more of an open wave and surface trough pass across Illinois on Tuesday, with precip starting briefly as rain early Tuesday then changing to snow, with light accums possible. With such large swings in each models solutions from cycle to cycle, along with differences between the models, only minor changes were made to the forecast from late Monday night through Tues night. The blended initialization shifted the Likely PoPs on Tuesday to areas southeast of Decatur, with high chance PoPs elsewhere in central Illinois. The actual PoP numbers were relatively close to the previous forecast in general. Precip type scenarios were tied to a warm surge on Tuesday, then rain changing to snow from W to E Tues night, as colder air arrives behind the low/surface trough. Changes to this scenario are likely over the next couple of days before models start to converge on a solution. A break in the precip chances is expected for Wednesday as weak high pressure passes across IL. However, another upper level shortwave and surface trough are projected to pass over Illinois on Thursday. There will be higher chances of rain or snow southeast of the Illinois river, closer to the track of the upper vort max and jet dynamics. High temps will dip back below normal from Wednesday to Friday as the waves bring brief shots of cooler air to the region. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) ISSUED AT 1128 AM CST FRI FEB 26 2016 Ceilings are falling just below 3000 feet late this morning from KSPI-KCMI as a stratocumulus deck spreads southeast. Am expecting some modest improvement in heights by mid afternoon back into VFR range. The overall cloud deck will continue to push east, and should be out of the TAF sites by mid evening. Continue to have some concerns regarding fog potential overnight across east central Illinois, where snow is currently melting. SREF visibility probabilities showing 30-40% chance of 1 mile visibility between 09-12Z in this area, where the snow is thickest. A couple things that may help mitigate it are an increasing southerly wind which will set up after 06Z, as well as some higher clouds accompanying an upper level trough. Right now, will continue with prevailing MVFR visibilities at KCMI late tonight, with TEMPO periods at KBMI/KDEC where there is less snow cover. Any fog should burn off by 15Z with sunshine and winds increasing to around 10 knots. && .ILX Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Geelhart LONG TERM...Shimon AVIATION...Geelhart
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1128 AM CST FRI FEB 26 2016 .UPDATE... ISSUED AT 944 AM CST FRI FEB 26 2016 Most of the CWA east of I-55 saw the lower level clouds scatter out and skies were mostly sunny this morning, although cirrus clouds were still streaming overhead. Another stratocumulus deck was along and west of the Illinois River, and this will overspread the forecast area over the next few hours. RAP model shows the lower clouds and cirrus on the way out by late afternoon, and will continue with the trend of decreasing clouds over the northwest CWA late this afternoon. Zones/grids were recently updated to address the sky trends, with minor updates to the temperatures. && .SHORT TERM...(Today) ISSUED AT 330 AM CST FRI FEB 26 2016 1032 mb high pressure over central Texas and ridging northward across the eastern plains, will see the ridge over IL by 18Z/noon today and into the Ohio river valley by sunset. This will keep central and southeast IL dry today, though a northern stream upper level trof over the Dakotas will dive southeast into MO and IL by early evening. This will tend to bring mostly cloudy skies and seasonably cool temperatures today. A large break in the low clouds across the nw half of CWA and moving southeast toward I-57 early this morning, should fill back in during the morning as upper level trof approaches and diurnal cumulus/stratocumulus clouds develop. WNW winds 7-15 mph this morning becomes WSW this afternoon. Still have a couple inches of snow on ground over east central IL and kept cooler highs in the mid to upper 30s there, while lower 40s elsewhere. .LONG TERM...(Tonight through Thursday) ISSUED AT 330 AM CST FRI FEB 26 2016 Northern stream upper level trof/short wave to exit quickly southeast into the mid MS and Ohio river valleys by 06z/midnight tonight with clouds decreasing from nw to SE during the night in its wake. Lows tonight of 25-30F with coolest readings over east central IL. Upper level heights rise over IL Saturday with upper level flow become semi-zonal and allowing Pacific air to flow into IL this weekend and bringing a nice warmup. Any remaining snow pack over east central IL to likely all melt on Saturday with ample sunshine with increasing SW winds 10-15 mph and gusts of 20-25 mph by Saturday afternoon. Milder highs Saturday in the 50s, ranging from lower 50s east central IL to the upper 50s west central IL. Lows Sat night in the upper 30s and lower 40s as fair skies continue. Low pressure emerging from the southern Canadian Rockies into the northern plains Saturday evening, tracks eastward across central WI and lower MI Sunday. Breezy SW winds of 15 to 25 mph and gusts of 25 to 35 mph Sunday brings even milder temps with highs in the low to mid 60s, despite increasing clouds as skies become mostly cloudy Sunday afternoon. Continued to carry slight chance of showers by mid/late Sunday afternoon over northern half of CWA while better chances of showers and even isolated thunderstorms over ne IL Sunday afternoon and early Sunday evening closer to low pressure moving across the central Great Lakes. This pulls a cold front southeast across central IL sunday evening bringing 20-30% chances of rain showers to central and eastern IL. Dry behind this front as clouds decrease overnight Sunday night and Monday and turning a bit cooler. Lows Sunday night in the low to mid 30s. Highs Monday 50-55F with mostly sunny skies and still above normal for last day of February. Big changes in the 00Z forecast models with track and speed of strong low pressure ejecting from KS on Tue. Yesterday models where taking low pressure ne across the ohio river valley Wed. Today the GEM and ECMWF model take low pressure into central IL by 18Z Tue and then into the eastern Great Lakes by 06Z/midnight Tue night. The GFS model is much slower with low pressure over ne KS at 18Z Tue and over central IL at 06Z/midnight Tue night. Will stay close to blended initialization pops with some lean toward the more similar ECMWF and GEM camps. Still dry Monday night over central/eastern IL then think rain showers to develop from west to east during the day Tue with isolated thunderstorms possible over southern IL. Leaning toward faster GEM/ECMWF model would have cooler air arriving quicker Tue night with rain changing to light snow showers, especially after midnight Tue night over central IL and just slight chances on Wed but GEM and ECMWF models have pcpn east of IL by Wed. This storm track over central IL would keep better chances of snow accumulations north of our CWA. Highs Tue range from upper 40s nw of IL river to near 60F by Lawrenceville. Much cooler Wed with brisk WNW winds and highs in mid to upper 30s central IL and lower 40s in southeast IL. A clipper system moves into IL from the northern Rockies Thu bringing a chance of rain/snow and below normal highs in the mid to upper 30s central IL and lower 40s southeast IL. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) ISSUED AT 1128 AM CST FRI FEB 26 2016 Ceilings are falling just below 3000 feet late this morning from KSPI-KCMI as a stratocumulus deck spreads southeast. Am expecting some modest improvement in heights by mid afternoon back into VFR range. The overall cloud deck will continue to push east, and should be out of the TAF sites by mid evening. Continue to have some concerns regarding fog potential overnight across east central Illinois, where snow is currently melting. SREF visibility probabilities showing 30-40% chance of 1 mile visibility between 09-12Z in this area, where the snow is thickest. A couple things that may help mitigate it are an increasing southerly wind which will set up after 06Z, as well as some higher clouds accompanying an upper level trough. Right now, will continue with prevailing MVFR visibilities at KCMI late tonight, with TEMPO periods at KBMI/KDEC where there is less snow cover. Any fog should burn off by 15Z with sunshine and winds increasing to around 10 knots. && .ILX Watches/Warnings/Advisories... NONE. && $$ UPDATE...Geelhart SHORT TERM...07 LONG TERM...07 AVIATION...Geelhart
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
142 PM EST FRI FEB 26 2016 .UPDATE... ISSUED AT 125 PM EST FRI FEB 26 2016 WINDS WILL CONTINUE TO BECOME MORE ANTICYLCONIC OR WESTERLY THIS AFTERNOON AND FLURRIES SHOULD CONTINUE TO TAPER OFF FROM WEST TO EAST. LOW CLOUDS WILL REMAIN AND THIS SHOULD CONTINUE TO SUPPRESS TEMPERATURES AND HOLD MOST LOCATIONS INTO THE 30S FOR THE REMAINDER OF THE DAY. THE EXCEPTIONS WILL BE IN THE SOUTH WHERE THE LOW 40S ARE POSSIBLE AND THE HIGHEST ELEVATIONS ABOVE 2500 FEET WILL HOLD IN THE 20S. UPDATE ISSUED AT 1057 AM EST FRI FEB 26 2016 HOURLY GRIDS WERE UPDATED BASED ON RECENT OBSERVATIONS AND RADAR TRENDS. THIS LED TO NO SUBSTANTIAL CHANGE OTHER THAN TO COOL OFF THE RIDGES A BIT THROUGH EARLY AFTERNOON. SINCE SNOW SHOWERS CONTINUE TO WIND DOWN TO ISOLATED SNOW SHOWERS AND FLURRIES AS THE LOW LEVEL FLOW WILL BECOME MORE WESTERLY AND LOW LEVEL MOISTURE MORE SHALLOW. THE SNOW SHOWERS HAVE ALSO SHIFTED INTO THE NORTHEASTERN AND EASTERN COUNTIES. THE SPS WAS EXTENDED THROUGH NOON SINCE RIDGETOPS REMAIN AT OR BELOW FREEZING ACROSS THE NORTH AND EASTERN PART OF THE AREA. UPDATE ISSUED AT 700 AM EST FRI FEB 26 2016 ALTHOUGH BANDS OF LIGHT SNOW SHOWERS AND FLURRIES WILL CONTINUE INTO MID MORNING ACROSS FAR EASTERN PARTS OF THE AREA WE WILL LET THE WINTER WEATHER ADVISORY EXPIRE AT 7 AM WITH LITTLE ADDITIONAL ACCUMULATION EXPECTED. THE SPS WILL CONTINUE THROUGH 9:30 FOR THE ENTIRE AREA DUE TO A POTENTIAL FOR SLICK SPOTS WITH THE LAST OF THE SNOW SHOWERS AROUND AND TEMPERATURES NEAR FREEZING. HAVE UPDATED THE GRIDS TO REFLECT THE CURRENT RADAR AND OB TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATED ZONES...HWO...AND THE EXPIRATION FOR THE WSW WILL FOLLOW SHORTLY. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM EST FRI FEB 26 2016 07Z SFC ANALYSIS SHOWS HIGH PRESSURE PUSHING INTO KENTUCKY FROM THE WEST WHILE A DEEP LOW IS FOUND TO THE NORTHEAST. THERE REMAINS A FAIRLY TIGHT PRESSURE GRADIENT BETWEEN THESE SYSTEMS KEEPING THE WINDS GOING THROUGH EAST KENTUCKY THIS NIGHT. THIS IS SUPPORTING A WELL MIXED AIR MASS MAKING TEMPERATURES FAIRLY UNIFORM ACROSS THE CWA. ADDITIONALLY...THESE WINDS ARE NOT ADVECTING IN MUCH COLDER AIR MEANING TEMPERATURES CURRENTLY ARE NEAR FREEZING ACROSS THE AREA BUT NOT MUCH COLDER. AS A RESULT...SOME OF THE LINGERING SNOW SHOWERS ARE PARTIALLY MELTING CAUSING SOME REPORTS OF SLEET AND DRIZZLE. THE BANDED NATURE OF THE PCPN EARLY THIS MORNING IS STILL MAKING IT POSSIBLE TO SEE BRIEF DUSTINGS OF ACCUMULATION FOR THE LOWER ELEVATIONS WHILE PLACES ABOVE 2000 FT COULD PICK UP ANOTHER HALF AN INCH OF ACCUMULATION OR SO THROUGH DAWN. FOR THAT REASON WILL MAINTAIN THE ADVISORY UNTIL 12Z IN THOSE PLACES ALONG WITH RUNNING THE SPS THROUGH THE MORNING COMMUTE FOR POTENTIAL SLICK SPOTS ELSEWHERE. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY ALL TAKE A DEEP TROUGH EAST AND AWAY FROM THE REGION. IN THE WAKE OF THIS...THE PATTERN WILL TEMPORARILY FLATTEN OUT BEFORE ANOTHER...WEAKER...TROUGH MOVES THROUGH THE OHIO VALLEY FRIDAY NIGHT INTO SATURDAY. RIDGING FOLLOWS FOR SATURDAY WITH SIGNIFICANT HEIGHT RISES OVER KENTUCKY WHILE THE CORE OF THE TROUGH SLIPS OFF THE SOUTHEAST COAST. GIVEN THE AGREEMENT AMONG THE MODELS HAVE FAVORED A BLENDED SOLUTION WITH A LEAN TOWARD THE HRRR AND NAM12 IN THE NEAR TERM. SENSIBLE WEATHER WILL FEATURE THE BULK OF ANY LINGERING SNOW SHOWERS ENDING AROUND DAWN ALONG WITH THE RISK FOR ACCUMULATIONS. SOME LIGHT SNOW SHOWERS AND FLURRIES WILL BE POSSIBLE IN THE FAR EAST THROUGH LATE AFTERNOON. TEMPERATURES BOTTOMING OUT FOR MOST PLACES IN THE LOWER 30S SHOULD LIMIT THE POTENTIAL FOR SLICK SPOTS THIS MORNING...PARTICULARLY WITH ROAD TEMPS IN THE MID AND UPPER 30S. SKIES WILL BE MOSTLY CLOUDY TODAY ALLOWING FOR LITTLE HELP FROM SUNSHINE IN TEMPERATURES RECOVERING...REACHING INTO THE MID 30S NORTHEAST TO LOWER 40S IN THE SOUTH. CLOUDY CONDITIONS WILL CONTINUE TO BE THE RULE INTO SATURDAY MORNING KEEPING THE DIURNAL RANGE OF TEMPERATURES TO A MINIMUM. ACCORDINGLY...READINGS WILL BE DOWN IN THE MID 20S TONIGHT AND AGAIN FAIRLY UNIFORM ACROSS THE ELEVATIONS. FOR SATURDAY...TEMPERATURES WILL MORE SOLIDLY REBOUND AS SUNSHINE RETURNS...AND THE WINDS SWITCH MORE TO THE SOUTH... ALLOWING READINGS TO CLIMB INTO THE UPPER 40S AND LOWER 50S. USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WIND GRIDS THROUGH THE DAY THEN USED THE SUPERBLEND THEREAFTER. MADE ONLY MINOR ADJUSTMENTS TO THE T GRIDS GIVEN THE LIMITED TERRAIN DIFFERENCES ANTICIPATED TONIGHT. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS FOR LINGERING SNOW SHOWERS AND FLURRIES THIS MORNING IN THE FAR EAST...OTHERWISE POP VALUES WERE KEPT IN THE SINGLE DIGITS THROUGH SATURDAY...IN LINE WITH THE MOS GUIDANCE. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 230 AM EST FRI FEB 26 2016 FORECAST CONFIDENCE REMAINS DECENT THROUGH MONDAY MORNING AS EVIDENCE BY GOOD AGREEMENT IN OPERATIONAL MODELS AND ENSEMBLES. HOWEVER...SPREAD IN MODELS INCREASES QUICKLY BEYOND MONDAY...LEADING TO LARGER UNCERTAINTIES FOR MUCH OF NEXT WEEK. THE PERIOD WILL START AS A MID LEVEL TROUGH CROSSES THE CENTRAL PLAINS ON SUNDAY WITH HEIGHTS CONTINUING TO BUILD ACROSS THE OHIO RIVER VALLEY. STRONG SOUTHWESTERLY FLOW WILL DEVELOP THROUGH THE DAY WITH TEMPERATURES JUMPING INTO THE 60S. GFS/NAM BUFKIT SOUNDINGS ARE SHOWING GOOD MIXING ON SUNDAY WITH WIND GUSTS TOPPING 30 OR 35 MPH. STRONGEST WIND GUSTS ARE EXPECTED ACROSS CENTRAL KENTUCKY. WILL INCLUDE A MENTION OF THE STRONG WINDS IN THE HWO. IF IT WASN`T FOR THE WET FUEL CONDITIONS...WE WOULD GET VERY CLOSE TO RED FLAG CONDITIONS AS THE RH SHOULD DROP FAIRLY LOW SUNDAY AFTERNOON. WILL HIGHLIGHT THE CRITICAL WEATHER CONDITIONS IN THE FIRE WEATHER FORECAST. AS THE SHORTWAVE TROUGH PUSHES ACROSS THE OHIO RIVER VALLEY SUNDAY NIGHT...A COLD FRONT WILL BE DRAGGED ACROSS EASTERN KENTUCKY WITH A BAND OF SCATTERED TO NUMEROUS SHOWERS. WITH MODELS IN FAIRLY GOOD AGREEMENT AND A MODEST DEPTH OF MOISTURE WITH THE FRONTAL PASSAGE. HAVE BUMPED POPS UP A CATEGORY. RAIN SHOULD MOVE ON THROUGH FAIRLY QUICKLY...WITH DRY WEATHER SPREADING BACK IN EARLY MONDAY MORNING. ATTENTION THEN TURNS TO A SYSTEM FOR THE MIDDLE OF NEXT WEEK. AS MENTIONED ABOVE...MID/UPPER LEVEL FEATURES ARE NOT IN GREAT AGREEMENT...SO CONFIDENCE IN STRENGTH AND TIMING OF THE MIDWEEK SYSTEM IS VERY MUCH IN QUESTION. HOWEVER...IT DOES APPEAR A WARM UP WILL BE ON TAP AHEAD OF THE SYSTEM FOR LATE MONDAY THROUGH TUESDAY...BEFORE COOLER WEATHER RETURNS FOR THE LATTER HALF OF THE WEEK. SOMEWHERE IN THAT WINDOW...CONFIDENCE IS INCREASING FOR ANOTHER ROUND OF RAIN. BEST CHANCES RIGHT NOW WOULD BE TUESDAY NIGHT INTO WEDNESDAY...BUT COULD EASILY BE SHIFTED FORWARD OR BACKWARD IN TIME AS MODELS SHIFT AROUND. WHILE IT DOES TURN COOLER BEHIND THE SYSTEM...THE STRENGTH OF THE SYSTEM WILL DETERMINE HOW MUCH COLD AIR GETS DRAGGED IN BEHIND THE DEPARTING SYSTEM AND IF WE SEE ANOTHER ROUND OF LIGHT SNOW SHOWER ACTIVITY. FOR NOW...WILL KEEP THINGS MORE RAIN AS WE HEAD INTO MARCH AND CONDITIONS BECOME MORE HOSTILE TO SNOW CHANCES. IT DOES APPEAR ANOTHER CLIPPER SYSTEM MAY FOLLOW LATER IN THE WEEK...BUT AGAIN UNCERTAINTY IS VERY HIGH BEYOND THE MID WEEK SYSTEM. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 135 PM EST FRI FEB 26 2016 FLURRIES CONTINUE TO DIMINISH FROM WEST TO EAST WHILE LOW STRATOCU IS LEADING TO CIGS IN THE LOWER END OF VFR OR MVFR RANGE. THE LOW CLOUDS SHOULD LINGER FOR MUCH OF THE FIRST 12 TO 18 HOURS OF THE PERIOD...BEFORE SOME AT LEAST PARTIAL CLEARING LATE. WINDS WILL AVERAGE AT 10KT OR LESS THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...KAS AVIATION...JP
AREA FORECAST DISCUSSION
National Weather Service Paducah KY
1109 AM CST FRI FEB 26 2016 .UPDATE... Issued at 1107 AM CST FRI FEB 26 2016 For aviation section. UPDATE Updated aviation section for 12z taf issuance && .SHORT TERM...(Today through Sunday night) Issued at 250 AM CST FRI FEB 26 2016 The low levels continue to slowly dry out as surface high pressure builds east from the Plains into the Mississippi Valley. Skies cleared out in some areas overnight, but areas of low clouds are returning from the north as of 08z. The main forecast issue for today is how much low cloudiness to expect. Model forecast soundings as well as the RAP 1000/850 mb layer mean rh suggest that low clouds will not be quick to leave our area. The deepest and most persistent moisture is forecast to remain across the Evansville tri-state area today, where the forecast will stay mostly cloudy. Elsewhere, there should be occasional sunshine today, especially in the far western areas around kpof. The mixed layer has become more shallow since yesterday, and there is little evidence of any forcing for ascent. Therefore, no mention of precip will be made. High temps will be only slightly higher than Thursday, ranging from the lower to mid 40s in most places. Tonight will become mainly clear as dry southwest flow nudges the low clouds out of our area. Low temps will average around 30 degrees. Saturday and Saturday night will remain mostly clear as a 500 mb shortwave ridge moves southeast across our region. Low-level southwest flow will bring moderating temps, with highs reaching 60 in parts of southeast Missouri Saturday. Sunday will be milder than Saturday, but the combination of strong southwest winds and increasing high cloudiness could make it feel cooler. The nam model has been showing 30 to 40 knots of wind in the mixed layer (below 3000 feet). Surface wind gusts should be within that range Sunday afternoon. A low-amplitude 500 mb shortwave trough and its associated cold front will move across our region on Sunday night. Moisture will be limited, since this system is embedded in northwest flow. Will maintain small rain chances, primarily along and east of the Mississippi River. .LONG TERM...(Monday through Thursday) Issued at 250 AM CST FRI FEB 26 2016 Models are struggling with the pattern in the long term. Basically used the latest ensemble mean solutions incorporated with 50 percent blend of our previous 2 official gridded forecasts. Should be dry Monday, with our attention on a developing upper level system over the Pacific NW, quickly headed for the Rockies. The models have this strong wave somewhere over the central Plains by 12z Tuesday. Will continue with slight chance PoPs for showers Monday night. Area wide convective chances Tuesday. The GFS is notably slower than the EC/GEM and other solutions. Will not completely discount it. Plan on giving the other model consensus more weight. Continue PoPs for rain/showers Tuesday night, though slightly lower, with diminishing PoPs Wednesday. Have little confidence in the models from Wednesday night into Thursday. Will carry slight/low chance PoPs given the 00z/12z EC solutions show weak s/wv energy may generate some precip (mainly rain, mix north 1/2?) during this time frame. Temps will be a blend of latest MOS and previous 2 forecast cycles. && .AVIATION... Issued at 1105 AM CST FRI FEB 26 2016 VFR cigs will remain persistent through the day in the kevv/kowb areas. In the kpah/kcgi areas, mvfr to vfr cigs around 3k feet will be common. Clouds will depart our region late this afternoon and early this evening. && .PAH Watches/Warnings/Advisories... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ UPDATE...GM SHORT TERM...MY LONG TERM...CN AVIATION...GM