Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/22/15


AREA FORECAST DISCUSSION
NWS PHOENIX AZ
230 PM MST FRI MAR 20 2015 .SYNOPSIS...SOME LINGERING SHOWERS AND THUNDERSTORMS ARE LOCATED OVER THE HIGHER TERRAIN OF GILA COUNTY. OTHERWISE...THE REGION IS DRYING OUT WITH A RETURN OF MOSTLY CLEAR SKIES AND BACK TO A WARMING TREND. HIGH TEMPERATURES WILL BE IN THE 80S WITH THROUGH EARLY NEXT WEEK. && .DISCUSSION... SHOWERS AND THUNDERSTORMS HAVE BEGUN TO DEVELOP ALONG THE EASTERN PORTION OF THE MOGOLLON RIM...INCLUDING IN SOUTHERN GILA COUNTY. OUTFLOW FROM THESE STORMS IS BLOWING TOWARDS THE LOWER DESERTS OR SOUTHWEST. WE MAY SEE SOME CIRRUS BLOWOFF FROM THE STORMS FOR THE REST OF THE AFTERNOON. IN ADDITION...IT IS POSSIBLE THAT A FEW ISOLATED CELLS COULD DEVELOP CLOSER TO PHOENIX...PERHAPS OVER THE SUPERSTITIONS OR MAZATZAL RANGE...DURING THE NEXT FEW HOURS. OBSERVATIONS AT THE SURFACE ARE SHOWING MOST SITES WITH TEMPS IN THE 70S AND REMNANT MOISTURE STILL SHOWING WITH DEW POINTS MOSTLY IN THE 50S. THESE SHOULD BE FALLING OVER THE NEXT 24 HOURS AS WE RETURN TO BEING DOMINATED BY HIGH PRESSURE...WARMING TEMPERATURES...AND DRIER AIR. LOW PRESSURE IS CURRENTLY IN PLACE JUST OFFSHORE OF THE NORTHERN BAJA PENINSULA. WV IMAGERY SHOWS SOME DRY AIR INTRUSION WRAPPING INTO THE LOW BUT STILL A GOOD BELT OF MOISTURE ON THE NORTHWEST SIDE OF THE LOW...FROM NORTHERN BAJA UP THROUGH SOUTHWEST AZ ON UP TO NORTHWEST NM. ALSO ON WV IMAGERY SOME SIGNS OF A RIDGE BEGINNING TO MOVE BACK INTO THE REGION WITH A DRY SLOT SHOWING FROM OVER SAN DIEGO UP THROUGH THE LAKE MEAD...COLORADO RIVER REGION. MODELS INDICATE THE LOW PRESSURE WILL VERY SLOWLY MOVE EASTWARD FOR ANOTHER 24 HOURS BEFORE BEING ABSORBED BY THE LARGE SCALE WESTERLIES ONCE THE LOW REACHES WEST TEXAS LATER ON SATURDAY. BY THEN ZONAL FLOW ALOFT WILL TAKE OVER AND BUILD BACK SOME RIDGING OVER AZ AND CA. THIS WILL BRING A RETURN TO WARMER TEMPS AND MOSTLY CLEAR CONDITIONS TO THE REGION. BY MID WEEK ANOTHER NEW TROUGH WILL DROP DOWN INSIDE THE NORTHWESTERLY FLOW AND ATTEMPT TO CUTOFF ANOTHER LOW PRESSURE SYSTEM BY THURSDAY MORNING. GFS IS RATHER AGGRESSIVELY CALLING FOR DEVELOPMENT OF A PRONOUNCED CUT OFF LOW OFF THE BAJA PENINSULA. CONFIDENCE LEVELS ATTM NOT THAT STRONG AS TO WHAT IMPACTS MAY BE FELT IN OUR REGION AS THERE IS SOME DIVERGENCE IN THE VARIOUS MODEL SOLUTIONS. SO...WE SHALL HAVE TO WAIT AND SEE IF THERE IS MUCH CHANCE FOR CLOUDS AND OR PRECIP FOR THE REGION. && .PREVIOUS DISCUSSION... /ISSUED AT 155 MST FRI MAR 20 2015/... EARLY MORNING WATER VAPOR IMAGERY REVEALS LOW PRESSURE OVER THE GULF OF CALIFORNIA...AND CONTINUES TO DEPICT A SERIES OF WEAK SHORTWAVE TROUGHS ROTATING AROUND THE PARENT CIRCULATION. THE LOW HAS MOVED SOUTHWARD SINCE THURSDAY EVENING AND MOST OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA IS BEGINNING TO EXPERIENCE THE EFFECTS OF STRONG SUBSIDENCE...BUT A FEW SHOWERS PERSIST ACROSS THE AREA /MAINLY SOUTH-CENTRAL ARIZONA/ AS OF 0830Z. RAINFALL AMOUNTS SINCE MIDNIGHT HAVE BEEN VERY LIGHT...ON THE ORDER OF A FEW HUNDREDTHS OR LESS. WITH RAIN ACROSS THE REGION ON THURSDAY AND ELEVATED DEWPOINTS IN THE LOWER 50S...THERE REMAINS A NON-ZERO CHANCE OF FOG THROUGH THE EARLY MORNING HOURS BUT AT THIS POINT IT APPEARS THERE IS JUST ENOUGH CLOUD COVER AND ENOUGH BL MIXING TO PRECLUDE WIDESPREAD FOG DEVELOPMENT. RECENT RUNS OF THE HRRR ARE HINTING AT THE POTENTIAL FOR FOG DEVELOPMENT ACROSS THE WEST VALLEY FROM BUCKEYE INTO LA PAZ COUNTY ALTHOUGH SATELLITE INDICATES QUITE A BIT OF CLOUD COVER. AREA WEBCAMS ARE FOG FREE AS WELL AND I WILL KEEP THE MENTION OF FOG OUT OF THE FORECAST. ANOMALOUSLY HIGH ATMOSPHERIC MOISTURE /PWATS IN THE 99TH PERCENTILE ACROSS PORTIONS OF ARIZONA/ WILL REMAIN IN PLACE TODAY AND THE MAJORITY OF OPERATIONAL HI-RES MODELS INDICATE ANOTHER ROUND OF SHOWERS ARE POSSIBLE THIS AFTERNOON. HI-RES WRF GUIDANCE AND HRRR INDICATE SHOWERS WILL DEVELOP AGAIN LATE THIS MORNING INTO THE AFTERNOON HOURS AND REMAIN CONFINED TO AREAS FROM PHOENIX EASTWARD. AS SUCH...I REFINED POPS SLIGHTLY TO INDICATE 20 PERCENT CHANCES IN THE METRO AND CLOSER TO 50-60 POPS AROUND GLOBE/MIAMI AND POINTS EAST. ALSO INTRODUCED A MENTION OF THUNDER AS MLCAPES /WHILE LARGELY UNIMPRESSIVE BY MONSOON STANDARDS/ WILL APPROACH 100-250 J/KG THIS AFTERNOON. THE UPPER LOW WILL SLOWLY DEPART THE AREA FRIDAY NIGHT INTO SATURDAY WITH ZONAL FLOW SETTING UP ACROSS THE SOUTHWESTERN CONUS THIS WEEKEND. THIS WILL ALLOW CONDITIONS TO RAPIDLY DRY OUT ON SATURDAY /DEWPOINTS WILL FALL NOTICEABLY INTO THE LOWER 40S AND MID 30S/ WHILE ALLOWING TEMPERATURES TO RISE BACK INTO THE UPPER 80S. THIS MORNING`S 00Z SUITE OF OPERATIONAL MODELS DON`T INDICATE A REMARKABLE RISE IN 500MB HEIGHTS /ONLY FORECAST TO REACH APPROX 578-580DM/ AND THUS I WON`T FORECAST ANYTHING NEAR RECORD VALUES. HOWEVER...ABOVE NORMAL TEMPS CERTAINLY LOOK LIKE A SAFE BET THROUGH THE WEEKEND INTO EARLY NEXT WEEK. A MID-WEEK TROUGH WILL MOVE THROUGH THE GREAT BASIN AND ARRIVE IN SOUTHEAST CALIFORNIA/ARIZONA WEDNESDAY AFTERNOON. GIVEN ITS OVER- LAND TRAJECTORY I WOULD EXPECT THE SYSTEM TO BE RELATIVELY MOISTURE STARVED AND THE NAEFS SUPPORTS THE IDEA OF UNIMPRESSIVE PWATS COINCIDENT WITH THE PASSAGE OF THE TROUGH. NONETHELESS WITH A PERIOD OF STRONG SOUTHERLY FLOW AHEAD OF THE TROUGH AND MODEST MOISTURE TRANSPORT...FELT IT WORTHWHILE TO INCLUDE CLIMO-LIKE POPS WEDNESDAY/THURSDAY. IF NOTHING ELSE THE TROUGH WILL BRING IN HIGH CLOUD COVER AND SLIGHTLY COOLER TEMPERATURES BEFORE DEPARTING THE AREA LATE NEXT WEEK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... CLOUDS SHOULD REMAIN IN THE 8-10KFT RANGE...WITH GRADUAL CLEARING BY 03Z SATURDAY AS THE UPPER LEVEL LOW SLOWLY DEPARTS THE AREA. WINDS WILL PERSIST WITH USUAL DIURNAL HEADINGS WITH SPEEDS 8KTS OR LESS. GIVEN RAINFALL AMOUNTS WERE GREATEST ACROSS THE WEST...NORTH AND SE VALLEY WITH KPHX ON THE DRIER SIDE OF ACCUMULATIONS...FEEL THAT AT LEAST KSDL COULD SEE A REMOTE CHANCE OF SOME VCFG FRIDAY AM IF SKIES CLEAR OUT ENOUGH...OR AT THE LEAST A REDUCTION IN VIS. KEEPING MENTION OF VCFG MENTION IN TAFS. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... FEW TO SCT MID- HIGH LEVEL CLOUDS CONTINUE TO CLEAR THROUGHOUT TODAY. WINDS EXPECTED TO REMAIN MOSTLY LIGHT AND VARIABLE THROUGH FRIDAY AFTERNOON. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... AN AREA OF LOW PRESSURE WILL EXIT TO THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO FILTER INTO THE LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE TEENS ACROSS THE CENTRAL AND WESTERN DESERTS. THERE WILL BE A LINGERING SLIGHT CHANCE OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF PHOENIX...MAINLY TO THE EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A DRY WESTERLY FLOW ALOFT WILL DOMINATE THE WEATHER PATTERN AS HIGHER PRESSURE ALOFT SLOWLY BUILDS ACROSS THE REGION. HIGH TEMPERATURES WILL STEADILY CLIMB WITH THE WARMER LOWER DESERTS REACHING THE UPPER 80S TO LOW 90S BY MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS EXPECTED OVER THE NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH DESERTS READINGS BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST HALF OF NEXT WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY THROUGH MONDAY WITH WINDS INCREASING TUESDAY AND WEDNESDAY...BECOMING BREEZY FROM THE WEST DURING THE AFTERNOON HOURS EACH DAY. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...WATERS/LEINS AVIATION....DEWEY/NOLTE FIRE WEATHER...BRECKENRIDGE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
855 AM MST FRI MAR 20 2015 .SYNOPSIS... LOW PRESSURE WILL SLOWLY EXIT THE REGION TODAY WITH A FEW SHOWERS STILL POSSIBLE THIS AFTERNOON TO THE EAST OF PHOENIX. DRIER AND WARMER AIR WILL MOVE INTO THE AREA THIS WEEKEND AND REMAIN IN PLACE THROUGH NEXT WEEK. TEMPERATURES WILL EVENTUALLY RETURN TO THE UPPER 80S TO AROUND 90 BY EARLY NEXT WEEK. && .DISCUSSION... VISIBLE SATELLITE IMAGERY THIS MORNING SHOWS A BAND OF MID LEVEL CLOUDS ACROSS CENTRAL TO SOUTHWEST AZ. RADAR IMAGERY IS NOT SHOWING ANY PRECIP ECHOES IN THAT AREA AT THIS TIME. AT THE SURFACE...MOISTURE REMAINS IN PLACE WITH MOST SITES IN AZ SHOWING LESS THAN 5 DEG DEW POINT DEPRESSION. INDEED...THE VIS DOES INDICATE SOME AREAS OF LINGERING FOG...ALTHOUGH NOT IN OUR CWA BUT SOME POCKETS CAN BE SEEN PRIMARILY IN YAVAPAI COUNTY. IT IS HARD TO DETECT IF THERE IS ANY FOG IN MARICOPA AND PINAL COUNTIES DUE TO THAT MID CLOUD LAYER BLOCKING THE SATELLITE VIEW. STILL...COULD NOT RULE OUT POSSIBILITY THAT THERE MAY BE A LITTLE LINGERING MORNING FOG IN SOME ISOLATED VALLEY AREAS. MOST LOCATIONS ACROSS OUR CWA ARE SHOWING UPPER 50S TO LOW 60S THIS MORNING AND APPEAR TO BE ON TARGET FOR HIGH TEMPS TODAY IN THE LOW 80S FOR MOST LOCATIONS. LOW PRESSURE IS CURRENTLY IN PLACE JUST OFFSHORE OF THE NORTHERN BAJA PENINSULA. WV IMAGERY SHOWS SOME DRY AIR INTRUSION WRAPPING INTO THE LOW BUT STILL A GOOD BELT OF MOISTURE ON THE NORTHWEST SIDE OF THE LOW...FROM NORTHERN BAJA UP THROUGH SOUTHWEST AZ ON UP TO NORTHWEST NM. ALSO ON WV IMAGERY SOME SIGNS OF A RIDGE BEGINNING TO MOVE BACK INTO THE REGION WITH A DRY SLOT SHOWING FROM OVER SAN DIEGO UP THROUGH THE LAKE MEAD...COLORADO RIVER REGION. MODELS INDICATE THE LOW PRESSURE WILL VERY SLOWLY MOVE EASTWARD FOR ANOTHER 24 HOURS BEFORE BEING ABSORBED BY THE LARGE SCALE WESTERLIES ONCE THE LOW REACHES WEST TEXAS LATER ON SATURDAY. BY THEN ZONAL FLOW ALOFT WILL TAKE OVER AND BUILD BACK SOME RIDGING OVER AZ AND CA. THIS WILL BRING A RETURN TO WARMER TEMPS AND MOSTLY CLEAR CONDITIONS TO THE REGION. BY MID WEEK ANOTHER NEW TROUGH WILL DROP DOWN INSIDE THE NORTHWESTERLY FLOW AND ATTEMPT TO CUTOFF ANOTHER LOW PRESSURE SYSTEM BY THURSDAY MORNING. GFS IS RATHER AGGRESSIVELY CALLING FOR DEVELOPMENT OF A PRONOUNCED CUT OFF LOW OFF THE BAJA PENINSULA. CONFIDENCE LEVELS ATTM NOT THAT STRONG AS TO WHAT IMPACTS MAY BE FELT IN OUR REGION AS THERE IS SOME DIVERGENCE IN THE VARIOUS MODEL SOLUTIONS. SO...WE SHALL HAVE TO WAIT AND SEE IF THERE IS MUCH CHANCE FOR CLOUDS AND OR PRECIP FOR THE REGION. && .PREVIOUS DISCUSSION... /ISSUED AT 155 MST FRI MAR 20 2015/... EARLY MORNING WATER VAPOR IMAGERY REVEALS LOW PRESSURE OVER THE GULF OF CALIFORNIA...AND CONTINUES TO DEPICT A SERIES OF WEAK SHORTWAVE TROUGHS ROTATING AROUND THE PARENT CIRCULATION. THE LOW HAS MOVED SOUTHWARD SINCE THURSDAY EVENING AND MOST OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA IS BEGINNING TO EXPERIENCE THE EFFECTS OF STRONG SUBSIDENCE...BUT A FEW SHOWERS PERSIST ACROSS THE AREA /MAINLY SOUTH-CENTRAL ARIZONA/ AS OF 0830Z. RAINFALL AMOUNTS SINCE MIDNIGHT HAVE BEEN VERY LIGHT...ON THE ORDER OF A FEW HUNDREDTHS OR LESS. WITH RAIN ACROSS THE REGION ON THURSDAY AND ELEVATED DEWPOINTS IN THE LOWER 50S...THERE REMAINS A NON-ZERO CHANCE OF FOG THROUGH THE EARLY MORNING HOURS BUT AT THIS POINT IT APPEARS THERE IS JUST ENOUGH CLOUD COVER AND ENOUGH BL MIXING TO PRECLUDE WIDESPREAD FOG DEVELOPMENT. RECENT RUNS OF THE HRRR ARE HINTING AT THE POTENTIAL FOR FOG DEVELOPMENT ACROSS THE WEST VALLEY FROM BUCKEYE INTO LA PAZ COUNTY ALTHOUGH SATELLITE INDICATES QUITE A BIT OF CLOUD COVER. AREA WEBCAMS ARE FOG FREE AS WELL AND I WILL KEEP THE MENTION OF FOG OUT OF THE FORECAST. ANOMALOUSLY HIGH ATMOSPHERIC MOISTURE /PWATS IN THE 99TH PERCENTILE ACROSS PORTIONS OF ARIZONA/ WILL REMAIN IN PLACE TODAY AND THE MAJORITY OF OPERATIONAL HI-RES MODELS INDICATE ANOTHER ROUND OF SHOWERS ARE POSSIBLE THIS AFTERNOON. HI-RES WRF GUIDANCE AND HRRR INDICATE SHOWERS WILL DEVELOP AGAIN LATE THIS MORNING INTO THE AFTERNOON HOURS AND REMAIN CONFINED TO AREAS FROM PHOENIX EASTWARD. AS SUCH...I REFINED POPS SLIGHTLY TO INDICATE 20 PERCENT CHANCES IN THE METRO AND CLOSER TO 50-60 POPS AROUND GLOBE/MIAMI AND POINTS EAST. ALSO INTRODUCED A MENTION OF THUNDER AS MLCAPES /WHILE LARGELY UNIMPRESSIVE BY MONSOON STANDARDS/ WILL APPROACH 100-250 J/KG THIS AFTERNOON. THE UPPER LOW WILL SLOWLY DEPART THE AREA FRIDAY NIGHT INTO SATURDAY WITH ZONAL FLOW SETTING UP ACROSS THE SOUTHWESTERN CONUS THIS WEEKEND. THIS WILL ALLOW CONDITIONS TO RAPIDLY DRY OUT ON SATURDAY /DEWPOINTS WILL FALL NOTICEABLY INTO THE LOWER 40S AND MID 30S/ WHILE ALLOWING TEMPERATURES TO RISE BACK INTO THE UPPER 80S. THIS MORNING`S 00Z SUITE OF OPERATIONAL MODELS DON`T INDICATE A REMARKABLE RISE IN 500MB HEIGHTS /ONLY FORECAST TO REACH APPROX 578-580DM/ AND THUS I WON`T FORECAST ANYTHING NEAR RECORD VALUES. HOWEVER...ABOVE NORMAL TEMPS CERTAINLY LOOK LIKE A SAFE BET THROUGH THE WEEKEND INTO EARLY NEXT WEEK. A MID-WEEK TROUGH WILL MOVE THROUGH THE GREAT BASIN AND ARRIVE IN SOUTHEAST CALIFORNIA/ARIZONA WEDNESDAY AFTERNOON. GIVEN ITS OVER- LAND TRAJECTORY I WOULD EXPECT THE SYSTEM TO BE RELATIVELY MOISTURE STARVED AND THE NAEFS SUPPORTS THE IDEA OF UNIMPRESSIVE PWATS COINCIDENT WITH THE PASSAGE OF THE TROUGH. NONETHELESS WITH A PERIOD OF STRONG SOUTHERLY FLOW AHEAD OF THE TROUGH AND MODEST MOISTURE TRANSPORT...FELT IT WORTHWHILE TO INCLUDE CLIMO-LIKE POPS WEDNESDAY/THURSDAY. IF NOTHING ELSE THE TROUGH WILL BRING IN HIGH CLOUD COVER AND SLIGHTLY COOLER TEMPERATURES BEFORE DEPARTING THE AREA LATE NEXT WEEK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... CLOUDS SHOULD REMAIN IN THE 8-10KFT RANGE...WITH GRADUAL CLEARING BY 03Z SATURDAY AS THE UPPER LEVEL LOW SLOWLY DEPARTS THE AREA. WINDS WILL PERSIST WITH USUAL DIURNAL HEADINGS WITH SPEEDS 8KTS OR LESS. GIVEN RAINFALL AMOUNTS WERE GREATEST ACROSS THE WEST...NORTH AND SE VALLEY WITH KPHX ON THE DRIER SIDE OF ACCUMULATIONS...FEEL THAT AT LEAST KSDL COULD SEE A REMOTE CHANCE OF SOME VCFG FRIDAY AM IF SKIES CLEAR OUT ENOUGH...OR AT THE LEAST A REDUCTION IN VIS. KEEPING MENTION OF VCFG MENTION IN TAFS. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... FEW TO SCT MID- HIGH LEVEL CLOUDS CONTINUE TO CLEAR THROUGHOUT TODAY. WINDS EXPECTED TO REMAIN MOSTLY LIGHT AND VARIABLE THROUGH FRIDAY AFTERNOON. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... AN AREA OF LOW PRESSURE WILL EXIT TO THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO FILTER INTO THE LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE TEENS ACROSS THE CENTRAL AND WESTERN DESERTS. THERE WILL BE A LINGERING SLIGHT CHANCE OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF PHOENIX...MAINLY TO THE EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A DRY WESTERLY FLOW ALOFT WILL DOMINATE THE WEATHER PATTERN AS HIGHER PRESSURE ALOFT SLOWLY BUILDS ACROSS THE REGION. HIGH TEMPERATURES WILL STEADILY CLIMB WITH THE WARMER LOWER DESERTS REACHING THE UPPER 80S TO LOW 90S BY MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS EXPECTED OVER THE NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH DESERTS READINGS BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST HALF OF NEXT WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY THROUGH MONDAY WITH WINDS INCREASING TUESDAY AND WEDNESDAY...BECOMING BREEZY FROM THE WEST DURING THE AFTERNOON HOURS EACH DAY. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...WATERS/LEINS AVIATION....DEWEY/NOLTE FIRE WEATHER...BRECKENRIDGE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
526 AM MST FRI MAR 20 2015 .UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS. && .SYNOPSIS... LOW PRESSURE WILL SLOWLY EXIT THE REGION TODAY...ALTHOUGH A FEW SHOWERS ARE STILL POSSIBLE THIS AFTERNOON TO THE EAST OF PHOENIX. DRIER AND WARMER AIR WILL MOVE INTO THE AREA THIS WEEKEND AND REMAIN IN PLACE THROUGH NEXT WEEK. TEMPERATURES WILL EVENTUALLY RETURN TO THE UPPER 80S/AROUND 90 BY EARLY NEXT WEEK. && .DISCUSSION.../ISSUED AT 155 MST FRI MAR 20 2015/... EARLY MORNING WATER VAPOR IMAGERY REVEALS LOW PRESSURE OVER THE GULF OF CALIFORNIA...AND CONTINUES TO DEPICT A SERIES OF WEAK SHORTWAVE TROUGHS ROTATING AROUND THE PARENT CIRCULATION. THE LOW HAS MOVED SOUTHWARD SINCE THURSDAY EVENING AND MOST OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA IS BEGINNING TO EXPERIENCE THE EFFECTS OF STRONG SUBSIDENCE...BUT A FEW SHOWERS PERSIST ACROSS THE AREA /MAINLY SOUTH-CENTRAL ARIZONA/ AS OF 0830Z. RAINFALL AMOUNTS SINCE MIDNIGHT HAVE BEEN VERY LIGHT...ON THE ORDER OF A FEW HUNDREDTHS OR LESS. WITH RAIN ACROSS THE REGION ON THURSDAY AND ELEVATED DEWPOINTS IN THE LOWER 50S...THERE REMAINS A NON-ZERO CHANCE OF FOG THROUGH THE EARLY MORNING HOURS BUT AT THIS POINT IT APPEARS THERE IS JUST ENOUGH CLOUD COVER AND ENOUGH BL MIXING TO PRECLUDE WIDESPREAD FOG DEVELOPMENT. RECENT RUNS OF THE HRRR ARE HINTING AT THE POTENTIAL FOR FOG DEVELOPMENT ACROSS THE WEST VALLEY FROM BUCKEYE INTO LA PAZ COUNTY ALTHOUGH SATELLITE INDICATES QUITE A BIT OF CLOUD COVER. AREA WEBCAMS ARE FOG FREE AS WELL AND I WILL KEEP THE MENTION OF FOG OUT OF THE FORECAST. ANOMALOUSLY HIGH ATMOSPHERIC MOISTURE /PWATS IN THE 99TH PERCENTILE ACROSS PORTIONS OF ARIZONA/ WILL REMAIN IN PLACE TODAY AND THE MAJORITY OF OPERATIONAL HI-RES MODELS INDICATE ANOTHER ROUND OF SHOWERS ARE POSSIBLE THIS AFTERNOON. HI-RES WRF GUIDANCE AND HRRR INDICATE SHOWERS WILL DEVELOP AGAIN LATE THIS MORNING INTO THE AFTERNOON HOURS AND REMAIN CONFINED TO AREAS FROM PHOENIX EASTWARD. AS SUCH...I REFINED POPS SLIGHTLY TO INDICATE 20 PERCENT CHANCES IN THE METRO AND CLOSER TO 50-60 POPS AROUND GLOBE/MIAMI AND POINTS EAST. ALSO INTRODUCED A MENTION OF THUNDER AS MLCAPES /WHILE LARGELY UNIMPRESSIVE BY MONSOON STANDARDS/ WILL APPROACH 100-250 J/KG THIS AFTERNOON. THE UPPER LOW WILL SLOWLY DEPART THE AREA FRIDAY NIGHT INTO SATURDAY WITH ZONAL FLOW SETTING UP ACROSS THE SOUTHWESTERN CONUS THIS WEEKEND. THIS WILL ALLOW CONDITIONS TO RAPIDLY DRY OUT ON SATURDAY /DEWPOINTS WILL FALL NOTICEABLY INTO THE LOWER 40S AND MID 30S/ WHILE ALLOWING TEMPERATURES TO RISE BACK INTO THE UPPER 80S. THIS MORNING`S 00Z SUITE OF OPERATIONAL MODELS DON`T INDICATE A REMARKABLE RISE IN 500MB HEIGHTS /ONLY FORECAST TO REACH APPROX 578-580DM/ AND THUS I WON`T FORECAST ANYTHING NEAR RECORD VALUES. HOWEVER...ABOVE NORMAL TEMPS CERTAINLY LOOK LIKE A SAFE BET THROUGH THE WEEKEND INTO EARLY NEXT WEEK. A MID-WEEK TROUGH WILL MOVE THROUGH THE GREAT BASIN AND ARRIVE IN SOUTHEAST CALIFORNIA/ARIZONA WEDNESDAY AFTERNOON. GIVEN ITS OVER- LAND TRAJECTORY I WOULD EXPECT THE SYSTEM TO BE RELATIVELY MOISTURE STARVED AND THE NAEFS SUPPORTS THE IDEA OF UNIMPRESSIVE PWATS COINCIDENT WITH THE PASSAGE OF THE TROUGH. NONETHELESS WITH A PERIOD OF STRONG SOUTHERLY FLOW AHEAD OF THE TROUGH AND MODEST MOISTURE TRANSPORT...FELT IT WORTHWHILE TO INCLUDE CLIMO-LIKE POPS WEDNESDAY/THURSDAY. IF NOTHING ELSE THE TROUGH WILL BRING IN HIGH CLOUD COVER AND SLIGHTLY COOLER TEMPERATURES BEFORE DEPARTING THE AREA LATE NEXT WEEK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... CLOUDS SHOULD REMAIN IN THE 8-10KFT RANGE...WITH GRADUAL CLEARING BY 03Z SATURDAY AS THE UPPER LEVEL LOW SLOWLY DEPARTS THE AREA. WINDS WILL PERSIST WITH USUAL DIURNAL HEADINGS WITH SPEEDS 8KTS OR LESS. GIVEN RAINFALL AMOUNTS WERE GREATEST ACROSS THE WEST...NORTH AND SE VALLEY WITH KPHX ON THE DRIER SIDE OF ACCUMULATIONS...FEEL THAT AT LEAST KSDL COULD SEE A REMOTE CHANCE OF SOME VCFG FRIDAY AM IF SKIES CLEAR OUT ENOUGH...OR AT THE LEAST A REDUCTION IN VIS. KEEPING MENTION OF VCFG MENTION IN TAFS. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... FEW TO SCT MID- HIGH LEVEL CLOUDS CONTINUE TO CLEAR THROUGHOUT TODAY. WINDS EXPECTED TO REMAIN MOSTLY LIGHT AND VARIABLE THROUGH FRIDAY AFTERNOON. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... AN AREA OF LOW PRESSURE WILL EXIT TO THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO FILTER INTO THE LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE TEENS ACROSS THE CENTRAL AND WESTERN DESERTS. THERE WILL BE A LINGERING SLIGHT CHANCE OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF PHOENIX...MAINLY TO THE EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A DRY WESTERLY FLOW ALOFT WILL DOMINATE THE WEATHER PATTERN AS HIGHER PRESSURE ALOFT SLOWLY BUILDS ACROSS THE REGION. HIGH TEMPERATURES WILL STEADILY CLIMB WITH THE WARMER LOWER DESERTS REACHING THE UPPER 80S TO LOW 90S BY MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS EXPECTED OVER THE NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH DESERTS READINGS BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST HALF OF NEXT WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY THROUGH MONDAY WITH WINDS INCREASING TUESDAY AND WEDNESDAY...BECOMING BREEZY FROM THE WEST DURING THE AFTERNOON HOURS EACH DAY. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...LEINS AVIATION....DEWEY/NOLTE FIRE WEATHER...BRECKENRIDGE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
155 AM MST FRI MAR 20 2015 .SYNOPSIS... LOW PRESSURE WILL SLOWLY EXIT THE REGION TODAY...ALTHOUGH A FEW SHOWERS ARE STILL POSSIBLE THIS AFTERNOON TO THE EAST OF PHOENIX. DRIER AND WARMER AIR WILL MOVE INTO THE AREA THIS WEEKEND AND REMAIN IN PLACE THROUGH NEXT WEEK. TEMPERATURES WILL EVENTUALLY RETURN TO THE UPPER 80S/AROUND 90 BY EARLY NEXT WEEK. && .DISCUSSION... EARLY MORNING WATER VAPOR IMAGERY REVEALS LOW PRESSURE OVER THE GULF OF CALIFORNIA...AND CONTINUES TO DEPICT A SERIES OF WEAK SHORTWAVE TROUGHS ROTATING AROUND THE PARENT CIRCULATION. THE LOW HAS MOVED SOUTHWARD SINCE THURSDAY EVENING AND MOST OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA IS BEGINNING TO EXPERIENCE THE EFFECTS OF STRONG SUBSIDENCE...BUT A FEW SHOWERS PERSIST ACROSS THE AREA /MAINLY SOUTH-CENTRAL ARIZONA/ AS OF 0830Z. RAINFALL AMOUNTS SINCE MIDNIGHT HAVE BEEN VERY LIGHT...ON THE ORDER OF A FEW HUNDREDTHS OR LESS. WITH RAIN ACROSS THE REGION ON THURSDAY AND ELEVATED DEWPOINTS IN THE LOWER 50S...THERE REMAINS A NON-ZERO CHANCE OF FOG THROUGH THE EARLY MORNING HOURS BUT AT THIS POINT IT APPEARS THERE IS JUST ENOUGH CLOUD COVER AND ENOUGH BL MIXING TO PRECLUDE WIDESPREAD FOG DEVELOPMENT. RECENT RUNS OF THE HRRR ARE HINTING AT THE POTENTIAL FOR FOG DEVELOPMENT ACROSS THE WEST VALLEY FROM BUCKEYE INTO LA PAZ COUNTY ALTHOUGH SATELLITE INDICATES QUITE A BIT OF CLOUD COVER. AREA WEBCAMS ARE FOG FREE AS WELL AND I WILL KEEP THE MENTION OF FOG OUT OF THE FORECAST. ANOMALOUSLY HIGH ATMOSPHERIC MOISTURE /PWATS IN THE 99TH PERCENTILE ACROSS PORTIONS OF ARIZONA/ WILL REMAIN IN PLACE TODAY AND THE MAJORITY OF OPERATIONAL HI-RES MODELS INDICATE ANOTHER ROUND OF SHOWERS ARE POSSIBLE THIS AFTERNOON. HI-RES WRF GUIDANCE AND HRRR INDICATE SHOWERS WILL DEVELOP AGAIN LATE THIS MORNING INTO THE AFTERNOON HOURS AND REMAIN CONFINED TO AREAS FROM PHOENIX EASTWARD. AS SUCH...I REFINED POPS SLIGHTLY TO INDICATE 20 PERCENT CHANCES IN THE METRO AND CLOSER TO 50-60 POPS AROUND GLOBE/MIAMI AND POINTS EAST. ALSO INTRODUCED A MENTION OF THUNDER AS MLCAPES /WHILE LARGELY UNIMPRESSIVE BY MONSOON STANDARDS/ WILL APPROACH 100-250 J/KG THIS AFTERNOON. THE UPPER LOW WILL SLOWLY DEPART THE AREA FRIDAY NIGHT INTO SATURDAY WITH ZONAL FLOW SETTING UP ACROSS THE SOUTHWESTERN CONUS THIS WEEKEND. THIS WILL ALLOW CONDITIONS TO RAPIDLY DRY OUT ON SATURDAY /DEWPOINTS WILL FALL NOTICEABLY INTO THE LOWER 40S AND MID 30S/ WHILE ALLOWING TEMPERATURES TO RISE BACK INTO THE UPPER 80S. THIS MORNING`S 00Z SUITE OF OPERATIONAL MODELS DON`T INDICATE A REMARKABLE RISE IN 500MB HEIGHTS /ONLY FORECAST TO REACH APPROX 578-580DM/ AND THUS I WON`T FORECAST ANYTHING NEAR RECORD VALUES. HOWEVER...ABOVE NORMAL TEMPS CERTAINLY LOOK LIKE A SAFE BET THROUGH THE WEEKEND INTO EARLY NEXT WEEK. A MID-WEEK TROUGH WILL MOVE THROUGH THE GREAT BASIN AND ARRIVE IN SOUTHEAST CALIFORNIA/ARIZONA WEDNESDAY AFTERNOON. GIVEN ITS OVER- LAND TRAJECTORY I WOULD EXPECT THE SYSTEM TO BE RELATIVELY MOISTURE STARVED AND THE NAEFS SUPPORTS THE IDEA OF UNIMPRESSIVE PWATS COINCIDENT WITH THE PASSAGE OF THE TROUGH. NONETHELESS WITH A PERIOD OF STRONG SOUTHERLY FLOW AHEAD OF THE TROUGH AND MODEST MOISTURE TRANSPORT...FELT IT WORTHWHILE TO INCLUDE CLIMO-LIKE POPS WEDNESDAY/THURSDAY. IF NOTHING ELSE THE TROUGH WILL BRING IN HIGH CLOUD COVER AND SLIGHTLY COOLER TEMPERATURES BEFORE DEPARTING THE AREA LATE NEXT WEEK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... UPPER TROUGH AXIS STILL OVERHEAD AZ AND LINGERING BOUNDARY LAYER MOISTURE WILL PROMOTE ISOLATED RAIN SHOWER DEVELOPMENT ACROSS CENTRAL AZ THIS EVENING. HI-RES RADAR REFLECTIVITY FORECASTS POINT TO THE BULK OF THE ACTIVITY REMAINING ALONG THE NORTHERN PERIPHERY OF THE PHX METRO. CANNOT RULE OUT A STRAY SHOWER SKIRTING ONE OF THE TERMINALS...BUT FEEL COVERAGE SHOULD NOT BE ENOUGH TO WARRANT VCSH INCLUSION IN 06Z TAFS. CLOUDS WILL GNLY BE IN THE 8-10KFT RANGE...VARYING FROM PERIODS OF NEAR CLEAR TO BKN COVERAGE AS THEY CIRCULATE AROUND THE AREA. WINDS TO TAKE UP USUAL DIURNAL HEADINGS WITH SPEEDS 8KTS OR LESS. RAINFALL AMOUNTS WERE GREATEST ACROSS THE WEST...NORTH AND SE VALLEY WITH KPHX ON THE DRIER SIDE OF ACCUMULATIONS. FEEL THAT AT LEAST KSDL COULD SEE A REMOTE CHANCE OF SOME VCFG FRIDAY AM IF SKIES CLEAR OUT ENOUGH. WILL CONTINUE VCFG MENTION WITH 06Z TAFS. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... FEW TO SCT MID-HIGH LEVEL CLOUD DECKS WILL DRIFT THROUGH THE AREA OVERNIGHT...GNLY REMAINING AOA 15KFT. WINDS WILL STAY RATHER LIGHT/VARIABLE OVER THE AREA THROUGH FRIDAY MORNING. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... AN AREA OF LOW PRESSURE WILL EXIT TO THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO FILTER INTO THE LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE TEENS ACROSS THE CENTRAL AND WESTERN DESERTS. THERE WILL BE A LINGERING SLIGHT CHANCE OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF PHOENIX...MAINLY TO THE EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A DRY WESTERLY FLOW ALOFT WILL DOMINATE THE WEATHER PATTERN AS HIGHER PRESSURE ALOFT SLOWLY BUILDS ACROSS THE REGION. HIGH TEMPERATURES WILL STEADILY CLIMB WITH THE WARMER LOWER DESERTS REACHING THE UPPER 80S TO LOW 90S BY MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS EXPECTED OVER THE NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH DESERTS READINGS BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST HALF OF NEXT WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY THROUGH MONDAY WITH WINDS INCREASING TUESDAY AND WEDNESDAY...BECOMING BREEZY FROM THE WEST DURING THE AFTERNOON HOURS EACH DAY. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...LEINS AVIATION...NOLTE/MEYERS FIRE WEATHER...BRECKENRIDGE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1111 AM MDT FRI MAR 20 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 433 AM MDT FRI MAR 20 2015 RESIDUAL MTN SNOW SHOWERS SHOULD QUICKLY DIMINISH ACROSS SOUTHERN SECTIONS OF THE FORECAST AREA THIS MORNING. BASED ON LATEST TRENDS FROM HRRR AND RAP13 AND PER COORD WITH SURROUNDING OFFICES...WILL BE TAKING DOWN THE HIGHLIGHTS FOR THE SOUTHERN MTS WITH THE MORNING PACKAGE. WILL STILL MAINTAIN SOME ISOLATED POPS THIS MORNING FOR THE SOUTHWEST MTS AND SOUTHERN PORTIONS OF THE SANGRE DE CRISTO RANGE AS THESE AREAS WILL STILL BE UNDER THE WEAK DEFORMATION/TROF AXIS...BUT NOT EXPECTING MUCH ACCUMULATION. WILL ALSO CARRY SOME PATCHY FOG FOR THE VALLEY LOCATIONS THIS MORNING GIVEN THE RESIDUAL LOW LEVEL MOISTURE AND CLEARING. FOR TODAY...DRIER AIR MOVES IN FROM THE NORTHWEST. TEMPERATURES SHOULD REBOUND NICELY FOR MOST AREAS AND WINDS WILL REMAIN LIGHT. WITH AFTERNOON HEATING...ALL MODELS SUGGEST CONVECTIVE RAIN AND SNOW SHOWERS WILL DEVELOP ACROSS THE SOUTHWEST MOUNTAINS AND SANGRE DE CRISTO RANGE DURING THE AFTERNOON. LAPSE RATES LOOK SUFFICIENTLY STEEP FOR ISOLATED EMBEDDED THUNDERSTORMS ACROSS THE SOUTHWEST MOUNTAINS. THIS COULD LEAD TO POCKETS OF MODERATE TO BRIEFLY HEAVY SNOW ACROSS THE HIGHER AREAS THIS AFTERNOON. ACCUMULATIONS SHOULD BE SPOTTY...BUT LOCAL AREAS COULD SEE A QUICK COUPLE INCHES OF SNOW. SHOWERS SHOULD COME TO AN END DURING THE EVENING WITH CLEARING SKIES. LEE TROF SHOULD KEEP TEMPERATURES WARMER ACROSS THE LOWER EASTERN SLOPES/I-25 CORRIDOR TONIGHT. -KT .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 433 AM MDT FRI MAR 20 2015 PRIMARY LONGER TERM METEOROLOGICAL CONCERNS INCLUDE TEMPERATURES...AMOUNT OF IMPACT NEXT SYSTEM WILL HAVE ON THE FORECAST DISTRICT LATER NEXT WEEK AND GUSTY WIND POTENTIAL AT TIMES. RECENT LONGER TERM COMPUTER SIMULATIONS...PV ANALYSIS AND FORECAST SOUNDINGS SUGGEST THAT BASICALLY DRY AND MILD TO WARM METEOROLOGICAL CONDITIONS SHOULD BE NOTED OVER THE MAJORITY OF THE FORECAST DISTRICT FROM SATURDAY INTO TUESDAY NIGHT AS ZONAL TO NORTHWESTERLY UPPER FLOW DEVELOPS OVER COLORADO. GUSTY WINDS AT TIMES ARE ALSO ANTICIPATED...ESPECIALLY FROM MONDAY INTO TUESDAY NIGHT. A RETURN TO A MORE UNSETTLED AND COOLER METEOROLOGICAL REGIME IS THEN EXPECTED FROM LATER WEDNESDAY INTO THURSDAY EVENING AS AN UPPER DISTURBANCE COMBINES WITH MOIST EASTERLY FLOW. IN ADDITION...WARMEST CONDITIONS ARE ANTICIPATED FROM SATURDAY INTO MONDAY WITH 700 MB TEMPERATURES APPROACHING 6C AT TIMES ALONG THE I-25 CORRIDOR...WHILE COOLEST TEMPERATURES DURING THE LONGER TERM ARE PROJECTED TO DEVELOP BY NEXT WEDNESDAY AND THURSDAY AS 700 MB TEMPERATURES CHALLENGE -8C AT TIMES OVER THE I-25 CORRIDOR. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1108 AM MDT FRI MAR 20 2015 KALS...ANY REMAINING LOW CLOUDS WILL DISSIPATE QUICKLY THROUGH 18Z. VFR CONDITIONS WILL PREVAIL THROUGH THIS AFTERNOON WITH LIGHT SOUTHERLY WINDS. SOUNDINGS ARE INDICATED THE POTENTIAL FOR LOW STRATUS OR FOG TO DEVELOP BY 12Z/SAT. KCOS AND KPUB...VFR CONDITIONS WITH LIGHT DIURNALLY DRIVEN WINDS THROUGH THE NEXT 24 HOURS. MOZLEY && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS PUEBLO CO
436 AM MDT FRI MAR 20 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 433 AM MDT FRI MAR 20 2015 RESIDUAL MTN SNOW SHOWERS SHOULD QUICKLY DIMINISH ACROSS SOUTHERN SECTIONS OF THE FORECAST AREA THIS MORNING. BASED ON LATEST TRENDS FROM HRRR AND RAP13 AND PER COORD WITH SURROUNDING OFFICES...WILL BE TAKING DOWN THE HIGHLIGHTS FOR THE SOUTHERN MTS WITH THE MORNING PACKAGE. WILL STILL MAINTAIN SOME ISOLATED POPS THIS MORNING FOR THE SOUTHWEST MTS AND SOUTHERN PORTIONS OF THE SANGRE DE CRISTO RANGE AS THESE AREAS WILL STILL BE UNDER THE WEAK DEFORMATION/TROF AXIS...BUT NOT EXPECTING MUCH ACCUMULATION. WILL ALSO CARRY SOME PATCHY FOG FOR THE VALLEY LOCATIONS THIS MORNING GIVEN THE RESIDUAL LOW LEVEL MOISTURE AND CLEARING. FOR TODAY...DRIER AIR MOVES IN FROM THE NORTHWEST. TEMPERATURES SHOULD REBOUND NICELY FOR MOST AREAS AND WINDS WILL REMAIN LIGHT. WITH AFTERNOON HEATING...ALL MODELS SUGGEST CONVECTIVE RAIN AND SNOW SHOWERS WILL DEVELOP ACROSS THE SOUTHWEST MOUNTAINS AND SANGRE DE CRISTO RANGE DURING THE AFTERNOON. LAPSE RATES LOOK SUFFICIENTLY STEEP FOR ISOLATED EMBEDDED THUNDERSTORMS ACROSS THE SOUTHWEST MOUNTAINS. THIS COULD LEAD TO POCKETS OF MODERATE TO BRIEFLY HEAVY SNOW ACROSS THE HIGHER AREAS THIS AFTERNOON. ACCUMULATIONS SHOULD BE SPOTTY...BUT LOCAL AREAS COULD SEE A QUICK COUPLE INCHES OF SNOW. SHOWERS SHOULD COME TO AN END DURING THE EVENING WITH CLEARING SKIES. LEE TROF SHOULD KEEP TEMPERATURES WARMER ACROSS THE LOWER EASTERN SLOPES/I-25 CORRIDOR TONIGHT. -KT .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 433 AM MDT FRI MAR 20 2015 PRIMARY LONGER TERM METEOROLOGICAL CONCERNS INCLUDE TEMPERATURES...AMOUNT OF IMPACT NEXT SYSTEM WILL HAVE ON THE FORECAST DISTRICT LATER NEXT WEEK AND GUSTY WIND POTENTIAL AT TIMES. RECENT LONGER TERM COMPUTER SIMULATIONS...PV ANALYSIS AND FORECAST SOUNDINGS SUGGEST THAT BASICALLY DRY AND MILD TO WARM METEOROLOGICAL CONDITIONS SHOULD BE NOTED OVER THE MAJORITY OF THE FORECAST DISTRICT FROM SATURDAY INTO TUESDAY NIGHT AS ZONAL TO NORTHWESTERLY UPPER FLOW DEVELOPS OVER COLORADO. GUSTY WINDS AT TIMES ARE ALSO ANTICIPATED...ESPECIALLY FROM MONDAY INTO TUESDAY NIGHT. A RETURN TO A MORE UNSETTLED AND COOLER METEOROLOGICAL REGIME IS THEN EXPECTED FROM LATER WEDNESDAY INTO THURSDAY EVENING AS AN UPPER DISTURBANCE COMBINES WITH MOIST EASTERLY FLOW. IN ADDITION...WARMEST CONDITIONS ARE ANTICIPATED FROM SATURDAY INTO MONDAY WITH 700 MB TEMPERATURES APPROACHING 6C AT TIMES ALONG THE I-25 CORRIDOR...WHILE COOLEST TEMPERATURES DURING THE LONGER TERM ARE PROJECTED TO DEVELOP BY NEXT WEDNESDAY AND THURSDAY AS 700 MB TEMPERATURES CHALLENGE -8C AT TIMES OVER THE I-25 CORRIDOR. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 433 AM MDT FRI MAR 20 2015 LOCAL LIFR CONDITIONS WILL BE POSSIBLE THIS MORNING AT KALS AS CLEARING SKIES AND MOIST SURFACE LAYER LEADS TO PATCHY FOG FORMATION ON THE VALLEY FLOOR. FOG SHOULD BURN OFF AROUND 15Z. KPUB COULD ALSO SEE SOME PATCHY FOG...BUT DON`T THINK VIS WILL DROP BELOW VFR TO PERHAPS BRIEF MVFR CONDITIONS. KCOS MAY KEEP ENOUGH OF A DRAINAGE WIND TO PREVENT FOG FORMATION. FOR THE REMAINDER OF TODAY...VFR CONDITIONS EXPECTED WITH LIGHT WINDS AT THE TAF SITES. ISOLATED SHOWERS WILL BE POSSIBLE ACROSS THE SANGRE DE CRISTO MOUNTAINS WITH SCATTERED SHOWERS ACROSS THE EASTERN SAN JUANS DURING THE AFTERNOON. LOCAL VIS AND CIGS COULD DROP INTO THE IFR CATEGORY FOR THESE AREAS...BUT SHOWERS SHOULD STAY CONFINED TO THE MTN AREAS WITH KALS REMAINING VFR. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS NEW YORK NY
812 PM EDT SAT MAR 21 2015 .SYNOPSIS... A COLD FRONT WILL MOVE ACROSS TONIGHT...FOLLOWED BY HIGH PRESSURE BUILDING FROM THE NORTHWEST TUESDAY. THE HIGH WILL MOVE TO THE EAST ON WEDNESDAY AS LOW PRESSURE APPROACHES FROM THE WEST. A COLD FRONT ASSOCIATED WITH THE LOW WILL MOVE ACROSS THURSDAY INTO THURSDAY NIGHT. HIGH PRESSURE WILL RETURN FROM FRIDAY INTO SATURDAY. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... RADAR INDICATING SOME LIGHT RAIN SHOWERS OR SPRINKLES MOVING INTO THE LOWER HUDSON VALLEY WITH RETURNS OF 14 TO 20 DBZ. AT SOME OF THE HIGHER ELEVATIONS COULD BE SOME SNOWFLAKES...FLURRIES FALLING. AT 23Z KMSV DOWN TO 2 1/2 MILES. ALSO HRRR PICKING UP ON SOME SPRINKLES THROUGH 02Z. COLD FRONT BACK THROUGH CENTRAL UPSTATE NEW YORK INTO CENTRAL PENNSYLVANIA AND UNDER MOSTLY CLOUDY CONDITIONS TEMPERATURES NOT FALLING OFF TOO QUICKLY...ESPECIALLY INLAND. ADJUSTED TEMPERATURES AND DEW POINTS FOR CURRENT TRENDS. WITH 700-500 HPA TROUGH AXIS ALREADY TO THE N/E THE BEST FORCING SHOULD STAY TO OUR N/E TONIGHT...ALLOWING FOR SURFACE COLD FRONTAL PASSAGE THIS EVENING/THE EARLY MORNING HOURS TO BE DRY. FOR LOWS TONIGHT...USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES. LOWS SHOULD BE AROUND 5 DEGREES BELOW NORMAL. TEMPERATURES WILL NOT FALL OFF THAT MUCH THIS EVENING AHEAD OF THE COLD FRONT...BUT SHOULD FALL OFF FAIRLY RAPIDLY AS MODERATE TO STRONG LOW LEVEL COLD ADVECTION ON SETS BEHIND THE FRONT DUE TO INCREASING NW WINDS. NW WINDS SHOULD GUST TO AROUND 20-30 MPH BY AROUND SUNRISE...WITH WIND CHILLS GENERALLY FROM THE MID TEENS TO AROUND 20. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... NW FLOW ALOFT SUNDAY AND SUNDAY NIGHT AS A PROTUBERANCE OF THE POLAR VORTEX PASSES TO OUR N THEN NE ACROSS SE CANADA/FAR N NEW ENGLAND. GIVEN ASSOCIATED LOW LEVEL COLD POOL...WILL BE A FIGHT BETWEEN DOWN SLOPING LOW LEVEL FLOW AND LOW LEVEL INSTABILITY FOR EXTENT OF CLOUD COVER BY SUNDAY AFTERNOON. FOR NOW GOING MAINLY MOSTLY SUNNY ON SUNDAY. FOR HIGHS SUNDAY A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX DOWN FROM 875 TO 850 HPA PER NAM FCST SOUNDINGS WAS USED. HIGHS SHOULD BE AROUND 15 DEGREES BELOW NORMAL...WITH MOST AREAS STRUGGLING TO REACH THE LOWER TO MID 30S AND HIGHER ELEVATIONS STRUGGLING TO REACH THE 30 DEGREE MARK. NW WINDS GUSTING TO AROUND 30 MPH...WITH SOME OCCASIONAL GUSTS TO 35 OR MAYBE EVEN 40 MPH WILL KEEP WIND CHILLS MAINLY FROM THE UPPER TEENS TO MID 20S. FOR LOWS SUNDAY NIGHT A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER TEMPERATURES WAS USED...WITH VALUES FORECAST TO BE AROUND 15 DEGREES BELOW NORMAL. WINDS DIMINISH THROUGH THE NIGHT...BUT STILL SHOULD PRODUCE WIND CHILLS MAINLY IN THE SINGLE DIGITS. && .LONG TERM /MONDAY THROUGH SATURDAY/... SURFACE CANADIAN HIGH PRESSURE WILL BE BUILDING INTO THE AREA MONDAY INTO TUESDAY NIGHT WHILE ALOFT A WEAK UPPER TROUGH REMAINS ACROSS THE NORTHEAST AND INTO EASTERN CANADA. A WEAK SHORTWAVE ROTATES THROUGH TUESDAY...HOWEVER THERE IS LITTLE MID AND LOWER LEVEL SUPPORT...WITH SUBSIDENCE ASSOCIATED WITH THE HIGH...AND LITTLE MOISTURE. THE SHORTWAVE MOVE THROUGH WITH JUST SOME HIGH CLOUDINESS. WITH THE RIDGE MOVING OFFSHORE WEDNESDAY WARM ADVECTION SETS UP LATE TUESDAY NIGHT INTO WEDNESDAY WITH A DEVELOPING WARM FRONTAL BOUNDARY TO THE WEST AND SOUTH...THROUGH CENTRAL PENNSYLVANIA TO SOUTHERN NEW JERSEY. LIGHT SHOWERS WILL BE POSSIBLE BY WEDNESDAY AFTERNOON WITH INCREASING ISENTROPIC LIFT WITH THE FRONT. IN ADDITION THE WARM ADVECTION WILL QUICKLY REPLACE ANY COLD AIR AND ALL LIQUID PRECIPITATION IS EXPECTED. MINOR DIFFERENCES WITH THE TIMING OF THE COLD FRONT LATE THURSDAY INTO THURSDAY NIGHT. HAVE BROUGHT THE FRONT THROUGH SLOWLY...THURSDAY NIGHT...MORE TOWARD THE ECMWF...AS THE FLOW BECOMES MORE PARALLEL TO THE FRONT. BROAD UPPER TROUGH REMAINS INTO NEXT WEEKEND AS SURFACE HIGH SLOWLY BUILDS. COULD BE SOME POST FRONTAL RAIN SHOWERS...RAIN AND SNOW SHOWERS INLAND...AND WILL KEEP SLIGHT CHANCE POPS FRIDAY INTO SATURDAY. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... A COLD FRONT WILL MOVE THROUGH THIS EVENING. BUILDING HIGH PRESSURE WILL FOLLOW OVERNIGHT INTO SUNDAY. THE COLD FRONT IS PRECEDED BY SPRINKLES/SHOWERS THAT COULD BRING BRIEF MVFR CONDS TO SOME TERMINALS...OTHERWISE VFR CONDS EXPECTED. IF OBS IN WESTERN PA ARE ANY INDICATION...WINDS GUSTS RIGHT AFTER COLD FROPA /02Z KSWF...03Z NYC METRO...04Z KBDR-KISP...AND 05Z KGON/ COULD BE SEVERAL KT STRONGER THAN FCST. GUSTS THEN MAY SUBSIDE FOR A FEW HRS LATE TONIGHT BEFORE INCREASING WITH DAYTIME HEATING/MIXING ON SUNDAY. WIND GUSTS MAY ALSO PEAK CLOSER TO 30 KT IN THE AFTERNOON...BUT THESE GUSTS WILL BE INFREQUENT. .OUTLOOK FOR 00Z MON THROUGH THU... .SUNDAY NIGHT...VFR. NW WINDS G20-25 KT. .MON...VFR. NW WINDS G20KT. .TUE...VFR. .WED...CHANCE OF SHOWERS WITH MVFR CONDS IN THE AFTERNOON. .THU...CHANCE OF SHOWERS WITH MVFR CONDS. SW WINDS G20-25 KT. && .MARINE... WIND AND SEAS FORECAST ON TRACK...NO CHANGES AT THIS TIME. SE SWELLS PERSIST ON THE COASTAL OCEAN WATERS...KEEPING THE SEAS UP. WINDS INCREASE BEHIND A COLD FRONT TONIGHT...BRINGING GUSTS TO SCA LEVELS ON ALL WATERS AFTER MIDNIGHT TONIGHT...WITH SCA GUSTS CONTINUING ON ALL WATERS THROUGH SUNDAY AFTERNOON. SCA LEVEL GUSTS ARE EXPECTED TO CONTINUE ON THE COASTAL OCEAN WATERS...EASTERN SOUND AND THE BAYS OF LONG ISLAND SUNDAY NIGHT. AS A RESULT HAVE EXTENDED THE SCA ON ALL WATERS THROUGH SUNDAY AFTERNOON AND ON THE COASTAL OCEAN WATERS...EASTERN SOUND AND THE BAYS OF LONG ISLAND THROUGH SUNDAY NIGHT. HIGH PRESSURE WILL BE BUILDING INTO THE WATERS MONDAY AND MOVE EAST OF THE WATERS WEDNESDAY. WIND AND SEAS WILL REMAIN BELOW SMALL CRAFT LEVELS MONDAY THROUGH WEDNESDAY. AS THE HIGH MOVES OFF SHORE WEDNESDAY AND A LOW APPROACHES FROM THE WEST AN INCREASING SOUTHERLY FLOW WILL DEVELOP. ON THE OCEAN SMALL CRAFT GUSTS WILL BE POSSIBLE BY THURSDAY...AND SEAS BUILD TO 5 FT OR HIGHER BY THURSDAY. SMALL CRAFT CONDITIONS REMAIN INTO THURSDAY NIGHT. A COLD FRONT CROSSES THE WATERS THURSDAY NIGHT AND HIGH PRESSURE BUILD IN FROM THE WEST. WIND AND SEAS SUBSIDE TO BELOW SMALL CRAFT THURSDAY NIGHT AND REMAIN BELOW FRIDAY. && .HYDROLOGY... DRY THROUGH TUESDAY NIGHT. AROUND A HALF INCH OF PRECIPITATION IS EXPECTED FROM WEDNESDAY AFTERNOON THROUGH THURSDAY NIGHT. ICE BREAKUP/MOVEMENT ACROSS THE LOWER HUDSON VALLEY AND CONNECTICUT RIVERS/STREAMS IS EXPECTED TO BE LIMITED THROUGH EARLY NEXT WEEK WITH LITTLE RUNOFF AND BELOW SEASONABLE TEMPS. ISOLATED ICE JAMS ARE POSSIBLE...WHICH IF THEY OCCUR...COULD RESULT IN LOCALIZED FLOODING. SINCE ICE JAM FLOODING IS UNPREDICTABLE AND SUDDEN...INTERESTS ALONG ICE COVERED RIVERS SHOULD MONITOR NWS FORECASTS FOR THE LATEST INFORMATION. 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 WEB SITE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EDT SUNDAY FOR ANZ335-338. SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EDT MONDAY FOR ANZ330-340-345. SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ350-353-355. && $$ SYNOPSIS...MALOIT/MET NEAR TERM...MALOIT/MET SHORT TERM...MALOIT LONG TERM...MET AVIATION...GOODMAN MARINE...MALOIT/MET HYDROLOGY...MALOIT/MET
AREA FORECAST DISCUSSION
NWS ALBANY NY
621 PM EDT FRI MAR 20 2015 .SYNOPSIS... A STORM SYSTEM PASSING TO THE SOUTH WILL BRING SOME LIGHT SNOW TO THE REGION THROUGH THIS EVENING...MAINLY FOR AREAS TO THE SOUTH OF ALBANY. AN ARCTIC COLD FRONT WILL BRING SOME ADDITIONAL RAIN AND SNOW SHOWERS TO THE REGION ON SATURDAY...BEFORE YET ANOTHER VERY COLD AIR MASS MOVES INTO THE REGION FOR SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... AS OF 615 PM EDT...THE COMBINATION OF SFC LOW PRESSURE OFF THE DELMARVA COAST...AND A FAST MOVING SHORTWAVE MOVING ACROSS THE MID ATLANTIC REGION HAVE ALLOWED FOR A PERIOD OF LIGHT SNOWFALL OVER THE REGION LATE THIS AFTERNOON. THE STEADIEST SNOWFALL HAS BEEN FROM THE CAPITAL REGION ON SOUTHWARD...WITH THE HIGHEST REFLECTIVITY ECHOS ON KENX RADAR OVER THE SOUTHERN BERKSHIRES AND NW CT. WITH THIS BEING A FAST MOVING SYSTEM...PRECIP LOOKS TO BE COMING TO AN END THIS EVENING. THE REGIONAL MOSAIC RADAR ALREADY SHOWS THE BACK EDGE OF THE STEADY PRECIP SHIELD ACROSS CENTRAL NY AND IT/S ADVANCING EASTWARD. THE LATEST 21Z 3KM HRRR SHOWS THE STEADY PRECIP SHOULD BE ENDING THIS EVENING BETWEEN 7 PM AND 9 PM...WITH ONLY A FEW LINGERING SNOW SHOWERS FOR THE MID HUDSON VALLEY...NW CT AND BERKSHIRES BETWEEN 9 PM AND 10 PM. TOTAL SNOWFALL WILL RANGE FROM A COATING TO AN INCH FOR NORTHERN AND CENTRAL AREAS...INCLUDING THE CAPITAL REGION...TO AROUND 1 TO 3 INCHES FOR THE CATSKILLS...MID HUDSON VALLEY...TACONICS...BERKSHIRES AND NW CT. ONLY FAR SOUTHERN AREAS WILL BE CLOSE TO THE HIGHER END OF THE RANGE...AS SNOW RATIOS HAVE BEEN FAIRLY LOW AND THE LIGHT INTENSITY HAS ALLOWED SOME MELTING DUE TO THE WARM GROUND AND STRONG MARCH SUN. AFTERWARD...IT SHOULD JUST REMAIN CLOUDY THROUGH THE REMAINDER OF THE OVERNIGHT HOURS. WITH THE CLOUDS AROUND...TEMPS WON/T DROP TOO MUCH...BUT OVERNIGHT LOWS LOOK TO BE IN THE 20S IN MOST AREAS. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... ON SATURDAY...A STRONG ARCTIC FRONTAL BOUNDARY WILL BE APPROACHING FROM THE GREAT LAKES REGION. THIS FRONT LOOKS TO CROSS DURING THE AFTN HOURS FROM WEST TO EAST. THIS FRONT WILL HAVE A STRONG THERMAL GRADIENT ASSOCIATED WITH IT...WITH TEMPS ALOFT RAPIDLY DROPPING OFF BEHIND THE BOUNDARY. AHEAD OF THE FRONT...SOUTHERLY FLOW SHOULD ALLOW TEMPS TO WARM INTO THE UPPER 30S TO MID 40S ACROSS THE REGION. A BAND OF PRECIPITATION LOOKS TO ACCOMPANY THE BOUNDARY. INITIALLY...PRECIP WILL LIKELY BE RAIN SHOWERS. ALTHOUGH MOISTURE WILL BE LIMITED...THE STRONG SFC CONVERGENCE SHOULD ALLOW FOR A BAND OF SHOWERS FOR MOST AREAS. WITH MID LEVEL LAPSE RATES /700-500 HPA/ WILL BE AROUND 6-7 DEGREES C/KM...THE SHOWERS MAY HAVE SOME CONVECTIVE GROWTH TO THEM...AND MAY BE CAPABLE OF PRODUCING SOME GRAUPEL. THE 4KM BTV WRF SHOWS A BROKEN LINE OF THESE CONVECTIVE SHOWERS WITH SOME HEAVIER ECHOES MOVING ACROSS THE AREA DURING THE AFTN HOURS. WITH THE RAPIDLY COOLING BOUNDARY LAYER...RAIN SHOWERS LOOKS TO SWITCH OVER TO SNOW SHOWERS BEFORE ENDING...FIRST HAPPENING IN THE HIGH TERRAIN. IT/S TOUGH TO SAY IF SHOWERS WILL LAST LONG ENOUGH IN VALLEY AREAS FOR THESE TO BE A CHANGEOVER TO SNOW SHOWERS IN THOSE AREAS BEFORE ENDING DURING THE EARLY EVENING. A QUICK COATING TO AN INCH OR TWO IS POSSIBLE FOR THE HIGH TERRAIN...ESP THE WESTERN AND SOUTHERN ADIRONDACKS. TEMPS SHOULD QUICKLY FALL DURING THE EVENING HOURS. OVERNIGHT LOWS ON SAT NIGHT LOOK TO BE IN THE TEENS FOR MOST AREAS...WITH SOME SINGLE DIGITS IN THE ADIRONDACKS. MOST AREAS WILL SEE PRECIP END WITH THE PASSAGE OF THE BOUNDARY ON SAT EVENING...BUT SOME UPSLOPE AREAS MAY CONTINUE TO SEE SNOW SHOWERS SAT NIGHT IN THE ADIRONDACKS AND GREENS. IN ADDITION...SOME LAKE EFFECT ACTIVITY OFF LAKE ONTARIO MAY BRING SOME CELLULAR SNOW SHOWERS ACROSS THE MOHAWK VALLEY AND SCHOHARIE COUNTY BY SAT NIGHT INTO SUN MORNING AS WELL....BUT ADDITIONAL SNOW ACCUMULATION LOOKS LIGHT. ASIDE FROM A FEW UPSLOPE SNOW SHOWERS IN THE ADIRONDACKS AND PERHAPS THE SOUTHERN GREENS ON SUNDAY...IT LOOKS DRY FOR SUN INTO SUNDAY NIGHT. HOWEVER...IT WILL BE VERY COLD...AS 850 HPA TEMPS FALL TO AROUND -20 DEGREES C. THESE COLD TEMPS ALOFT WILL PROMOTE GOOD MIXING...SO IT WILL BE RATHER BREEZY DURING THE DAY SUNDAY AS WELL...WITH GUSTS OVER 25 MPH POSSIBLE. MAX TEMPS WILL LIKELY ONLY BE IN THE MID 20S TO MID 30S FOR VALLEY AREAS...WITH HIGH TERRAIN HIGHS IN THE TEENS TO LOW 20S. THESE TEMPS ARE 15-20 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. TEMPS WILL CONTINUE TO BE VERY COLD FOR SUNDAY NIGHT...WITH LOWS IN THE SINGLE DIGITS AND TEENS. A FEW SPOTS IN THE ADIRONDACKS WILL EVEN FALL BELOW ZERO AS WELL. THE WINDS WILL DIMINISH SOMEWHAT FOR SUNDAY NIGHT...BUT WON/T BECOME CALM. THIS WILL ALLOW FOR WIND CHILL VALUES 10 BELOW TO 10 ABOVE FOR MOST AREAS...ALTHOUGH WIND CHILL VALUES WILL BE 10 TO 20 BELOW FOR THE ADIRONDACKS. WHILE THESE FALL SHORT OF WIND CHILL ADVISORY CRITERIA...IT/S STILL VERY COLD FOR LATE MARCH. && .LONG TERM /MONDAY THROUGH FRIDAY/... THIS WILL BE A PERIOD OF MODERATING TEMPERATURES...WITH HIGH TEMPERATURES BEGINNING MONDAY NIGHT FROM AROUND 20 DEGREES TO THE UPPER 30S...AND BECOMING AROUND 15 TO 25 DEGREES MILDER BY THURSDAY. LOW TEMPERATURES IN THE SINGLE DIGITS AND TEENS MONDAY NIGHT WILL BE LONG GONE BY WEDNESDAY NIGHT AS READINGS WILL BE 15 TO 25 DEGREES MILDER. THE PERIOD WILL BEGIN WITH HIGH PRESSURE AND DRY CONDITIONS...WITH A STORM SYSTEM FROM THE ROCKIES BRINGING A MIX OF PRECIPITATION BY WEDNESDAY NIGHT. THE MAIN LOW WILL SCOOT ACROSS THE GREAT LAKES AND PASS JUST TO OUR NORTH THROUGH WEDNESDAY NIGHT...WITH THE PRECIPITATION BECOMING MORE SHOWERY BUT STILL MIXED. COLD AIR BEHIND THE COLD FRONT WILL LAG...BUT EVENTUALLY THE PRECIPITATION WILL CHANGE OVER TO SNOW SHOWERS WHERE IT STILL LINGERS NORTH AND WEST OF THE CAPITAL REGION THURSDAY NIGHT. BROAD HIGH PRESSURE BUILDS OVER THE WESTERN HALF OF THE COUNTRY AND IS POISED TO MAKE IT IN FOR THE NEXT WEEKEND. && .AVIATION /22Z FRIDAY THROUGH WEDNESDAY/... EXPECT VFR CONDITIONS AT ALL THE TAF SITES THROUGH EARLY AFTERNOON. LOW PRESSURE WILL BE MOVING OFF THE COAST SO FAR TO THE SOUTH...ANY SIGNIFICANT IMPACTS AND WIDESPREAD IFR CONDITIONS DUE TO SNOW WILL GENERALLY BE CONFINED TO THE KPOU AND KPSF TAF SITES. AT KPOU...CEILINGS WILL GRADUALLY TREND FROM MVFR TO IFR THROUGH THIS AFTERNOON WHILE VISIBILITIES WILL REMAIN IFR. CONDITIONS SHOULD LOWER TO IFR NEAR 21Z AT KPSF. AT KALB EXPECT CONDITIONS TO ONLY LOWER TO MVFR CIGS/VSBYS STARTING AROUND 20Z. AT KGFL EXPECT FLIGHT CONDITIONS WILL REMAIN VFR THROUGH EARLY TONIGHT...AND HAVE ONLY INDICATED VCSH THERE BETWEEN 20/21Z AND 21/01Z. AFTER 00Z...FLIGHT CONDITIONS WILL BEGIN TO IMPROVE AT KALB/KPOU/KPSF. BY 03Z EXPECT THE SNOW TO HAVE ENDED. HOWEVER...LOW LEVEL MOISTURE AND LIGHT WINDS WILL RESULT IN CIGS REMAINING MVFR THROUGH THE NIGHT...ALONG WITH MVFR VISIBILITIES DUE TO FOG. VISIBILITIES WILL IMPROVE THE VFR BY AROUND 14Z...BUT CEILINGS SHOULD REMAIN MVFR. SURFACE WINDS WILL NOT BE MUCH OF A FACTOR THIS TAF PERIOD. WINDS WILL BE BE SOUTH OR SOUTHEAST AT 4 TO 8 KT AT TIMES...DIMINISHING TO NEAR CALM TONIGHT...THEN SOUTH AT 6 KT OR LESS TOMORROW MORNING. OUTLOOK... SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN. SUNDAY: LOW OPERATIONAL IMPACT. BREEZY NO SIG WX. SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. MONDAY-WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... THERE CONTINUES TO BE A SOLID SNOWPACK IN PLACE OVER MUCH OF THE REGION. WHILE SNOW HAS THINNED SOMEWHAT FOR THE HUDSON VALLEY REGION...ONE TO THREE FEET OF SNOW REMAINS IN THE HIGHER ELEVATIONS. WITH COLD TEMPERATURES EXPECTED OVER THE NEXT FEW DAYS...LITTLE MELTING OF THE SNOW WILL OCCUR. ALTHOUGH THE FIRE WEATHER SEASON OFFICIALLY BEGAN ON MARCH 16TH...WIDESPREAD FIRE WEATHER CONCERNS WILL BE MINIMAL UNTIL MELTING OF THE SNOW OCCURS. AS ALWAYS...SPOT FORECASTS ARE READILY AVAILABLE IF REQUESTED. && .HYDROLOGY... WIDESPREAD HYDROLOGIC CONCERNS ARE NOT ANTICIPATED OVER THE NEXT FIVE DAYS. TEMPERATURES WILL BE BELOW FREEZING THIS EVENING INTO TONIGHT...WITH LIGHT SNOW TAPERING OFF. HOWEVER...AHEAD OF AN ARCTIC COLD FRONT...TEMPERATURES WILL BRIEFLY SPIKE INTO THE UPPER 30S TO MID 40S ACROSS THE REGION. SOME SNOW MELT WILL LIKELY OCCUR ON SATURDAY AND A SOME LIGHT RAIN OR SNOW SHOWERS ARE POSSIBLE WITH THE BOUNDARY...BUT AMOUNTS WILL BE VERY LIGHT. COLDER AIR WILL QUICKLY RETURN TO THE REGION LATE SUNDAY WITH MAINLY BELOW FREEZING TEMPS SATURDAY NIGHT THROUGH TUESDAY MORNING. BY TUESDAY INTO WEDNESDAY...IT LOOKS TO REMAIN MAINLY DRY...BUT DAYTIME TEMPERATURES WILL RISE ABOVE FREEZING INTO THE 40S. SOME MELTING WILL LIKELY OCCUR...AND RIVER TRACES WILL FOLLOW A DIURNAL SNOWMELT PATTERN TYPICALLY SEEN IN THE EARLY SPRING. DUE TO THE COLD TEMPERATURES IN PLACE...MELTING WILL BE LIMITED THROUGH TUESDAY MORNING...ALTHOUGH THE SNOW AND ICE WILL CONTINUE TO BE SLOWLY REDUCED DUE TO SUBLIMATION. WITH ONLY SMALL AMOUNTS OF PRECIP EXPECTED AND LITTLE MELTING EXPECTED...ICE BREAKUP OR ICE JAMS ARE NOT ANTICIPATED FOR MOST AREAS. HOWEVER...A SMALL ICE JAM ON ANY SMALLER STREAMS FOR FAR SOUTHERN AREAS CANNOT BE RULED OUT...BUT WIDESPREAD PROBLEMS ARE NOT EXPECTED THROUGH THE MIDDLE OF THE UPCOMING WEEK. AFTERWARD...WE WILL HAVE TO WATCH THE PROSPECTS FOR RAINFALL AND SEE HOW WARM TEMPERATURES CAN RISE IN THE LATE WEEK PERIOD. 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 NEAR TERM...FRUGIS/11 SHORT TERM...FRUGIS LONG TERM...ELH AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
428 PM EDT FRI MAR 20 2015 .SYNOPSIS... A STORM SYSTEM PASSING TO THE SOUTH WILL BRING SOME LIGHT SNOW TO THE REGION THROUGH THIS EVENING...MAINLY FOR AREAS TO THE SOUTH OF ALBANY. AN ARCTIC COLD FRONT WILL BRING SOME ADDITIONAL RAIN AND SNOW SHOWERS TO THE REGION ON SATURDAY...BEFORE YET ANOTHER VERY COLD AIR MASS MOVES INTO THE REGION FOR SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... AS OF 428 PM EDT...THE COMBINATION OF SFC LOW PRESSURE OFF THE COAST OF THE MID ATLANTIC...AND A FAST MOVING SHORTWAVE MOVING ACROSS THE REGION HAVE ALLOWED FOR A PERIOD OF LIGHT SNOWFALL OVER THE REGION THIS AFTERNOON. THE STEADIEST SNOWFALL HAS BEEN FROM THE CAPITAL REGION ON SOUTHWARD...WITH THE HIGHEST REFLECTIVITY ECHOS ON KENX RADAR OVER THE MID HUDSON VALLEY AND NW CT. WITH THIS BEING A FAST MOVING SYSTEM...PRECIP LOOKS TO BE COMING TO AN END THIS EVENING. THE REGIONAL MOSAIC RADAR ALREADY SHOWS THE BACK EDGE OF THE STEADY PRECIP SHIELD ACROSS CENTRAL NY AND IT/S ADVANCING EASTWARD. THE LATEST 19Z 3KM HRRR SHOWS THE STEADY PRECIP SHOULD BE ENDING THIS EVENING BETWEEN 6 PM AND 8 PM...WITH ONLY A FEW LINGERING SNOW SHOWERS FOR THE MID HUDSON VALLEY...NW CT AND BERKSHIRES BETWEEN 8 PM AND 10 PM. TOTAL SNOWFALL WILL RANGE FROM A COATING TO AN INCH FOR NORTHERN AND CENTRAL AREAS...INCLUDING THE CAPITAL REGION...TO AROUND 1 TO 3 INCHES FOR THE CATSKILLS...MID HUDSON VALLEY...TACONICS...BERKSHIRES AND NW CT. ONLY FAR SOUTHERN AREAS WILL BE CLOSE TO THE HIGHER END OF THE RANGE...AS SNOW RATIOS HAVE BEEN FAIRLY LOW AND THE LIGHT INTENSITY HAS ALLOWED SOME MELTING DUE TO THE WARM GROUND AND STRONG MARCH SUN. AFTERWARD...IT SHOULD JUST REMAIN CLOUDY THROUGH THE REMAINDER OF THE OVERNIGHT HOURS. WITH THE CLOUDS AROUND...TEMPS WON/T DROP TOO MUCH...BUT OVERNIGHT LOWS LOOK TO BE IN THE 20S IN MOST AREAS. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... ON SATURDAY...A STRONG ARCTIC FRONTAL BOUNDARY WILL BE APPROACHING FROM THE GREAT LAKES REGION. THIS FRONT LOOKS TO CROSS DURING THE AFTN HOURS FROM WEST TO EAST. THIS FRONT WILL HAVE A STRONG THERMAL GRADIENT ASSOCIATED WITH IT...WITH TEMPS ALOFT RAPIDLY DROPPING OFF BEHIND THE BOUNDARY. AHEAD OF THE FRONT...SOUTHERLY FLOW SHOULD ALLOW TEMPS TO WARM INTO THE UPPER 30S TO MID 40S ACROSS THE REGION. A BAND OF PRECIPITATION LOOKS TO ACCOMPANY THE BOUNDARY. INITIALLY...PRECIP WILL LIKELY BE RAIN SHOWERS. ALTHOUGH MOISTURE WILL BE LIMITED...THE STRONG SFC CONVERGENCE SHOULD ALLOW FOR A BAND OF SHOWERS FOR MOST AREAS. WITH MID LEVEL LAPSE RATES /700-500 HPA/ WILL BE AROUND 6-7 DEGREES C/KM...THE SHOWERS MAY HAVE SOME CONVECTIVE GROWTH TO THEM...AND MAY BE CAPABLE OF PRODUCING SOME GRAUPEL. THE 4KM BTV WRF SHOWS A BROKEN LINE OF THESE CONVECTIVE SHOWERS WITH SOME HEAVIER ECHOES MOVING ACROSS THE AREA DURING THE AFTN HOURS. WITH THE RAPIDLY COOLING BOUNDARY LAYER...RAIN SHOWERS LOOKS TO SWITCH OVER TO SNOW SHOWERS BEFORE ENDING...FIRST HAPPENING IN THE HIGH TERRAIN. IT/S TOUGH TO SAY IF SHOWERS WILL LAST LONG ENOUGH IN VALLEY AREAS FOR THESE TO BE A CHANGEOVER TO SNOW SHOWERS IN THOSE AREAS BEFORE ENDING DURING THE EARLY EVENING. A QUICK COATING TO AN INCH OR TWO IS POSSIBLE FOR THE HIGH TERRAIN...ESP THE WESTERN AND SOUTHERN ADIRONDACKS. TEMPS SHOULD QUICKLY FALL DURING THE EVENING HOURS. OVERNIGHT LOWS ON SAT NIGHT LOOK TO BE IN THE TEENS FOR MOST AREAS...WITH SOME SINGLE DIGITS IN THE ADIRONDACKS. MOST AREAS WILL SEE PRECIP END WITH THE PASSAGE OF THE BOUNDARY ON SAT EVENING...BUT SOME UPSLOPE AREAS MAY CONTINUE TO SEE SNOW SHOWERS SAT NIGHT IN THE ADIRONDACKS AND GREENS. IN ADDITION...SOME LAKE EFFECT ACTIVITY OFF LAKE ONTARIO MAY BRING SOME CELLULAR SNOW SHOWERS ACROSS THE MOHAWK VALLEY AND SCHOHARIE COUNTY BY SAT NIGHT INTO SUN MORNING AS WELL....BUT ADDITIONAL SNOW ACCUMULATION LOOKS LIGHT. ASIDE FROM A FEW UPSLOPE SNOW SHOWERS IN THE ADIRONDACKS AND PERHAPS THE SOUTHERN GREENS ON SUNDAY...IT LOOKS DRY FOR SUN INTO SUNDAY NIGHT. HOWEVER...IT WILL BE VERY COLD...AS 850 HPA TEMPS FALL TO AROUND -20 DEGREES C. THESE COLD TEMPS ALOFT WILL PROMOTE GOOD MIXING...SO IT WILL BE RATHER BREEZY DURING THE DAY SUNDAY AS WELL...WITH GUSTS OVER 25 MPH POSSIBLE. MAX TEMPS WILL LIKELY ONLY BE IN THE MID 20S TO MID 30S FOR VALLEY AREAS...WITH HIGH TERRAIN HIGHS IN THE TEENS TO LOW 20S. THESE TEMPS ARE 15-20 DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. TEMPS WILL CONTINUE TO BE VERY COLD FOR SUNDAY NIGHT...WITH LOWS IN THE SINGLE DIGITS AND TEENS. A FEW SPOTS IN THE ADIRONDACKS WILL EVEN FALL BELOW ZERO AS WELL. THE WINDS WILL DIMINISH SOMEWHAT FOR SUNDAY NIGHT...BUT WON/T BECOME CALM. THIS WILL ALLOW FOR WIND CHILL VALUES 10 BELOW TO 10 ABOVE FOR MOST AREAS...ALTHOUGH WIND CHILL VALUES WILL BE 10 TO 20 BELOW FOR THE ADIRONDACKS. WHILE THESE FALL SHORT OF WIND CHILL ADVISORY CRITERIA...IT/S STILL VERY COLD FOR LATE MARCH. && .LONG TERM /MONDAY THROUGH FRIDAY/... THIS WILL BE A PERIOD OF MODERATING TEMPERATURES...WITH HIGH TEMPERATURES BEGINNING MONDAY NIGHT FROM AROUND 20 DEGREES TO THE UPPER 30S...AND BECOMING AROUND 15 TO 25 DEGREES MILDER BY THURSDAY. LOW TEMPERATURES IN THE SINGLE DIGITS AND TEENS MONDAY NIGHT WILL BE LONG GONE BY WEDNESDAY NIGHT AS READINGS WILL BE 15 TO 25 DEGREES MILDER. THE PERIOD WILL BEGIN WITH HIGH PRESSURE AND DRY CONDITIONS...WITH A STORM SYSTEM FROM THE ROCKIES BRINGING A MIX OF PRECIPITATION BY WEDNESDAY NIGHT. THE MAIN LOW WILL SCOOT ACROSS THE GREAT LAKES AND PASS JUST TO OUR NORTH THROUGH WEDNESDAY NIGHT...WITH THE PRECIPITATION BECOMING MORE SHOWERY BUT STILL MIXED. COLD AIR BEHIND THE COLD FRONT WILL LAG...BUT EVENTUALLY THE PRECIPITATION WILL CHANGE OVER TO SNOW SHOWERS WHERE IT STILL LINGERS NORTH AND WEST OF THE CAPITAL REGION THURSDAY NIGHT. BROAD HIGH PRESSURE BUILDS OVER THE WESTERN HALF OF THE COUNTRY AND IS POISED TO MAKE IT IN FOR THE NEXT WEEKEND. && .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... EXPECT VFR CONDITIONS AT ALL THE TAF SITES THROUGH EARLY AFTERNOON. LOW PRESSURE WILL BE MOVING OFF THE COAST SO FAR TO THE SOUTH...ANY SIGNIFICANT IMPACTS AND WIDESPREAD IFR CONDITIONS DUE TO SNOW WILL GENERALLY BE CONFINED TO THE KPOU AND KPSF TAF SITES. AT KPOU...CEILINGS WILL GRADUALLY TREND FROM MVFR TO IFR THROUGH THIS AFTERNOON WHILE VISIBILITIES WILL REMAIN IFR. CONDITIONS SHOULD LOWER TO IFR NEAR 21Z AT KPSF. AT KALB EXPECT CONDITIONS TO ONLY LOWER TO MVFR CIGS/VSBYS STARTING AROUND 20Z. AT KGFL EXPECT FLIGHT CONDITIONS WILL REMAIN VFR THROUGH EARLY TONIGHT...AND HAVE ONLY INDICATED VCSH THERE BETWEEN 20/21Z AND 21/01Z. AFTER 00Z...FLIGHT CONDITIONS WILL BEGIN TO IMPROVE AT KALB/KPOU/KPSF. BY 03Z EXPECT THE SNOW TO HAVE ENDED. HOWEVER...LOW LEVEL MOISTURE AND LIGHT WINDS WILL RESULT IN CIGS REMAINING MVFR THROUGH THE NIGHT...ALONG WITH MVFR VISIBILITIES DUE TO FOG. VISIBILITIES WILL IMPROVE THE VFR BY AROUND 14Z...BUT CEILINGS SHOULD REMAIN MVFR. SURFACE WINDS WILL NOT BE MUCH OF A FACTOR THIS TAF PERIOD. WINDS WILL BE BE SOUTH OR SOUTHEAST AT 4 TO 8 KT AT TIMES...DIMINISHING TO NEAR CALM TONIGHT...THEN SOUTH AT 6 KT OR LESS TOMORROW MORNING. OUTLOOK... SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN. SUNDAY: LOW OPERATIONAL IMPACT. BREEZY NO SIG WX. SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. MONDAY-WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... THERE CONTINUES TO BE A SOLID SNOWPACK IN PLACE OVER MUCH OF THE REGION. WHILE SNOW HAS THINNED SOMEWHAT FOR THE HUDSON VALLEY REGION...ONE TO THREE FEET OF SNOW REMAINS IN THE HIGHER ELEVATIONS. WITH COLD TEMPERATURES EXPECTED OVER THE NEXT FEW DAYS...LITTLE MELTING OF THE SNOW WILL OCCUR. ALTHOUGH THE FIRE WEATHER SEASON OFFICIALLY BEGAN ON MARCH 16TH...WIDESPREAD FIRE WEATHER CONCERNS WILL BE MINIMAL UNTIL MELTING OF THE SNOW OCCURS. AS ALWAYS...SPOT FORECASTS ARE READILY AVAILABLE IF REQUESTED. && .HYDROLOGY... WIDESPREAD HYDROLOGIC CONCERNS ARE NOT ANTICIPATED OVER THE NEXT FIVE DAYS. TEMPERATURES WILL BE BELOW FREEZING THIS EVENING INTO TONIGHT...WITH LIGHT SNOW TAPERING OFF. HOWEVER...AHEAD OF AN ARCTIC COLD FRONT...TEMPERATURES WILL BRIEFLY SPIKE INTO THE UPPER 30S TO MID 40S ACROSS THE REGION. SOME SNOW MELT WILL LIKELY OCCUR ON SATURDAY AND A SOME LIGHT RAIN OR SNOW SHOWERS ARE POSSIBLE WITH THE BOUNDARY...BUT AMOUNTS WILL BE VERY LIGHT. COLDER AIR WILL QUICKLY RETURN TO THE REGION LATE SUNDAY WITH MAINLY BELOW FREEZING TEMPS SATURDAY NIGHT THROUGH TUESDAY MORNING. BY TUESDAY INTO WEDNESDAY...IT LOOKS TO REMAIN MAINLY DRY...BUT DAYTIME TEMPERATURES WILL RISE ABOVE FREEZING INTO THE 40S. SOME MELTING WILL LIKELY OCCUR...AND RIVER TRACES WILL FOLLOW A DIURNAL SNOWMELT PATTERN TYPICALLY SEEN IN THE EARLY SPRING. DUE TO THE COLD TEMPERATURES IN PLACE...MELTING WILL BE LIMITED THROUGH TUESDAY MORNING...ALTHOUGH THE SNOW AND ICE WILL CONTINUE TO BE SLOWLY REDUCED DUE TO SUBLIMATION. WITH ONLY SMALL AMOUNTS OF PRECIP EXPECTED AND LITTLE MELTING EXPECTED...ICE BREAKUP OR ICE JAMS ARE NOT ANTICIPATED FOR MOST AREAS. HOWEVER...A SMALL ICE JAM ON ANY SMALLER STREAMS FOR FAR SOUTHERN AREAS CANNOT BE RULED OUT...BUT WIDESPREAD PROBLEMS ARE NOT EXPECTED THROUGH THE MIDDLE OF THE UPCOMING WEEK. AFTERWARD...WE WILL HAVE TO WATCH THE PROSPECTS FOR RAINFALL AND SEE HOW WARM TEMPERATURES CAN RISE IN THE LATE WEEK PERIOD. 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 NEAR TERM...FRUGIS SHORT TERM...FRUGIS LONG TERM...ELH AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
614 PM EDT FRI MAR 20 2015 .SYNOPSIS... A LOW PRESSURE SYSTEM, TRACKING TO OUR SOUTH, WILL MOVE ALONG THE COAST THEN TO OUR EAST THROUGH TONIGHT. A COLD FRONT WILL MOVE ACROSS THE AREA LATE SATURDAY INTO SATURDAY NIGHT. HIGH PRESSURE WILL BUILD TOWARD THE AREA SUNDAY AND MOVE ACROSS THE AREA MONDAY INTO TUESDAY, BEFORE SHIFTING EASTWARD INTO WEDNESDAY. A SLOW MOVING COLD FRONT WILL CROSS THE REGION ON THURSDAY INTO FRIDAY. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... WITH THIS UPDATE, WE ARE GOING TO EXTEND THE ADVISORY INTO THE OVERNIGHT OVER NORTHERN AND CENTRAL NEW JERSEY, MATCHING OKX`S TIMING WITH THE POTENTIAL OF SOME AREAS OF LIGHT FREEZING RAIN OR DRIZZLE. 0C AT 850MB ON THE RAP IS MATCHING THE CHANGE TO NON SNOW PRETTY WELL AND SHOWING UP ON THE CC DUAL POL ALSO. WE CANCELED SOME OF THE SOUTHERN ADVISORY COUNTIES, BUT WILL LET THE ADVISORY REMAIN UP ELSEWHERE WHERE THE CHANGEOVER JUST OCCURRED AS ITS TOO SOON AND FOR ANY RESIDUAL IMPACTS FOR THE COMMUTE HOME WESTERN PART OF OUR CWA. NO CHANGE FROM PREVIOUS THINKING AS WE ARE GETTING TO AROUND WARNING CRITERIA ON NON PAVED SURFACES, BUT HALF OR EVEN MORE THAN HALF AS MUCH ON PAVED SURFACES. STILL, POWER OUTAGES ARE OCCURRING THOUGH WE ARE NOT SURE IF THEY SNOW-TREE/WIRE RELATED. COULD SEE A SITUATION IN SOME PLACES WITH 1.0 INCH ON PAVEMENT AND 6 INCHES ON GRASS. WE TRIED TO WORD THAT IN SOME OF OUR STATEMENTS. YOU SEE THE RADAR WITH A NICE BAND BACK INTO E PA AND MOVING ENE HEADING FOR KBLM. THE HEAVIEST AXIS...VCNTY KRDG - KBLM WITH WIDESPREAD 5-6", POSSIBLY 7 INCH ON GRASS AND AROUND 2 ON PAVEMENT THERE. POSSIBLE ISOLATED POWER OUTAGES LATE TODAY NEAR THIS AXIS. PLEASE CONTINUE SENDING US YOUR ACCUM REPORTS, INCLUDING DIFFERENCE FROM PAVEMENT TO YOUR NORMAL MEASURING SFC AND WHETHER ROADS ARE BECOMING SLIPPERY. THANK YOU AGAIN FOR YOUR ASSISTANCE. TONIGHT...ACCUMULATING SNOW CONTINUES PAST 8 PM NNJ OR NE NJ WHILE SOUTH OF THAT, SOME RAIN/DRIZZLE, (POSSIBLE SPOTTY ICING SE PA). OPTED NOT TO HIT THE FREEZING RAIN RISK TOO HARD AS AM NOT CONFIDENT OF ITS OCCURRENCE. IT SHOULD DRY OUT OVERNIGHT WITH TEMPS NEARLY STEADY MOST OF THE NIGHT UNTIL IT PARTIALLY CLEARS TOWARD DAWN? PATCHY FOG MAY THICKEN UP TOWARD DAWN BUT NOT COVERED IN THE FCST. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/... A COLD FRONT WILL MOVE ACROSS THE AREA DURING THE DAY SATURDAY INTO SATURDAY NIGHT. THERE IS NOT A LOT OF MOISTURE/LIFT ASSOCIATED WITH THE FRONT ACROSS OUR AREA AS THE MAIN MOISTURE/LIFT ASSOCIATED WITH THE FRONT AND SHORT WAVE ALOFT PASS TO OUR NORTH. HOWEVER, THERE MAY BE ENOUGH COMBINED LIFT AND MOISTURE FOR SOME ISOLATED SHOWERS ACROSS NORTHWEST PORTIONS OF THE AREA LATE IN THE DAY SATURDAY INTO SATURDAY EVENING AS THE SOUTHERN EDGE OF THE SHORT WAVE MAY CLIP OUR NORTHERN AREAS, SO WE CONTINUED WITH SLIGHT CHANCE POPS OVER THE POCONOS. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... OVERVIEW...THE PERIOD STARTS WITH A COLD FRONT TRACKING NORTHWEST TO SOUTHEAST THROUGH THE REGION. SURFACE HIGH PRESSURE BUILDS IN ACROSS THE GREAT LAKES AND MID-ATLANTIC ON MONDAY. THE CENTER OF THE HIGH SHIFTS FROM ONTARIO ON SUNDAY AFTERNOON, TO THE GREAT LAKES ON MONDAY AFTERNOON, TO THE ATLANTIC SEABOARD ON TUESDAY AFTERNOON, AND THEN OFF THE COAST ON WEDNESDAY. ON WEDNESDAY NIGHT, SURFACE LOW PRESSURE ACROSS THE GREAT LAKES WILL BEGIN TO INTENSIFY. THE LOW IS FORECAST TO MOVE NEAR MAINE ON FRIDAY EVENING. A WARM FRONT, ATTACHED TO THE LOW WILL TRACK THROUGH THE REGION LATE ON WEDNESDAY. A SLOW MOVING COLD FRONT WILL CROSS THE FORECAST AREA LATE ON THURSDAY INTO FRIDAY. IMPACTS...AS THE TODAY`S SNOW MELTS OVER THE WEEKEND, WE WILL SEE CREEKS, STREAMS, AND RIVERS RISE A BIT. AS FOR OUR FORECAST POINTS, PEMBERTON AND PINE BROOK MAY ONCE AGAIN RISE INTO CAUTION STAGE. OTHER THAN THAT, THE EXTENDED PERIOD LOOKS FAIRLY BENIGN. THE PRECIP WITH THE SATURDAY COLD FRONT ACROSS THE NORTH LOOKS LIGHT AND MAINLY LIQUID. THE PRECIP WITH THE COLD FRONT ON THURSDAY LOOKS TO BE HEAVIER COMPARED TO SATURDAY, BUT ALL LIQUID. TEMPS...SLIGHTLY BELOW NORMAL ON SATURDAY, BELOW NORMAL SUNDAY THROUGH TUESDAY, AROUND NORMAL FOR WEDNESDAY AND THURSDAY, AND AT OR BELOW NORMAL FOR FRIDAY. WINDS...NO SIGNIFICANT WIND ISSUES EXPECTED. NORTHWEST WINDS SHOULD INCREASE BEHIND THE COLD FRONT SATURDAY NIGHT INTO SUNDAY. SOME GUSTS IN THE 20-25 MPH RANGE POSSIBLE. SOUTHERLY/SOUTHWESTERLY WINDS SHOULD INCREASE IN THE PRE-FRONTAL AIRMASS ON THURSDAY AND THEN GO NORTHWEST ON FRIDAY. GUSTS, ONCE AGAIN, IN THE 20-25 MPG RANGE LOOKS REASONABLE. PRECIP...RAIN CHANCES INCREASE WEDNESDAY THROUGH FRIDAY. && .AVIATION /22Z FRIDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. REMAINDER OF THIS AFTERNOON...IFR SNOW POSSIBLY LIFR IN HEAVY SNOW FOR A TIME BETWEEN NOW AND 21Z. PLEASE SEE TAFS FOR DETAILS TIMING MID- LATE AFTN SNOW CHANGING TO RAIN KILG/KPHL/KPNE/KTTN/KMIV AND KACY. PLOWING OPS FORESEEN AT KRDG/KABE/TTN WHERE 4 INCHES MAY ACCUMULATE ON PAVEMENTS AND 6 INCHES OR SO ON GRASS. SINCE LITTLE OR NO ACC ON KPHL RUNWAYS AT 16Z, HAVE DISCONTINUED MY STRONGER CONCERN THERE AND POINTS SEWD. NE WIND GUSTS 15-25 KT THIS AFTN, HIGHEST VCNTY KACY. TONIGHT...IFR SNOW KRDG-KABE AND IFR RAIN/SNOW KTTN AND IFR RAIN ELSEWHERE THIS EVENING IMPROVE TO MVFR CIGS AFTER 08Z/21. WIND BECOMING LIGHT NORTH OVERNIGHT AFTER EVENING NE GUSTS OF 15-20 KT. SATURDAY...CONDITIONS IMPROVING TO VFR BKN CIGS NEAR 4000 FT. WEST WIND. GUSTS UNDER 20 KT. OUTLOOK... SATURDAY NIGHT...A COLD FRONT WILL TRACK ACROSS THE TERMINALS. SCATTERED SHOWERS ARE POSSIBLE ACROSS THE NORTHERN TERMINALS. VFR IS EXPECTED, EXCEPT A TEMPO MVFR POSSIBLE IN A SHOWER. HIGH CONFIDENCE. SUNDAY-TUESDAY...VFR UNDER HIGH PRESSURE. GUSTY NORTHWEST WINDS AROUND 20 KT ARE POSSIBLE SATURDAY NIGHT AND SUNDAY. HIGH CONFIDENCE. WEDNESDAY...VFR CONTINUES AS THE SURFACE HIGH SHIFTS OFFSHORE. HIGH CONFIDENCE. && .MARINE... SCA CONTINUES AS POSTED. MAY NEED A SLIGHT UPWARD ADJUSTMENT LATE THIS EVENING FOR A SMALL CHANCE BRIEF GALE CONDITIONS ON THE ATLC WATERS ONLY (CENTRAL NJ TO DE COASTS) IN THE 6 PM TO 10 PM EDT TIME FRAME. OUTLOOK... SATURDAY NIGHT...SCA SEAS MAY PERSIST INTO SATURDAY EVENING ON THE OCEAN, OTHERWISE NO HEADLINES EXPECTED. A COLD FRONT IS FORECAST TO TRACK OFF THE COAST SATURDAY NIGHT. SUNDAY THROUGH WEDNESDAY...SUB-SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED. HIGH CONFIDENCE THROUGH THE PERIOD WITH THE EXCEPTION OF EARLY SUNDAY WHERE, AS OF NOW, WINDS ARE FORECAST UP TO 20 KT. SURFACE HIGH PRESSURE WILL DOMINATE THE 4 DAY PERIOD, MOVING FROM THE INTERIOR TO OFF THE COAST. && .CLIMATE... SNOW WHILE SIGNIFICANT ACROSS A LARGE PORTION OF OUR AREA, IS NOT EXPECTED TO EXCEED RECORD VALUES. FOR PERSPECTIVE: MARCH 20 DAILY RECORD SNOWFALL VALUES FOLLOW 1958 WAS THE YEAR. KABE 16.5 - 1958 KACY 5.0 - 1958 KILG 10.3 - 1958 KPHL 9.6 - 1958 LATEST OCCURRENCE OF MEASURABLE SNOW AND AMOUNT DURING THE 2013-2014 WINTER FOLLOWS... KABE - 4/15/14 0.3" KACY - 3/16/14 0.3" (NOTE: LATEST OCCURRENCE ON RECORD IS 4/24/56 0.4") KPHL - 3/25/14 0.4" KILG - 3/25/14 0.7" && .PHI WATCHES/WARNINGS/ADVISORIES... PA...WINTER WEATHER ADVISORY UNTIL 10 PM EDT THIS EVENING FOR PAZ054-055-060>062-070-071-101>106. NJ...WINTER WEATHER ADVISORY UNTIL 2 AM EDT SATURDAY FOR NJZ001- 007>010-012>015-019-020-026-027. WINTER WEATHER ADVISORY UNTIL 10 PM EDT THIS EVENING FOR NJZ017-018. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ450>455. SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ431. && $$ SYNOPSIS...KRUZDLO NEAR TERM...DRAG/GIGI SHORT TERM...DRAG LONG TERM...KRUZDLO AVIATION...DRAG/KRUZDLO MARINE...DRAG/KRUZDLO CLIMATE...
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
840 PM EDT SAT MAR 21 2015 .DISCUSSION... CURRENT-OVERNIGHT...DAYTIME CUMULUS FIELD DISSIPATES DURING THE EVENING. MANUAL OBSERVATION REPORTING SITES ARE RECORDING MOSTLY CLOUDY SKIES DUE TO HIGH CLOUDINESS. THE IR...WATER VAPOR SATELLITE AND RAP UPPER AIR FORECAST LOOPS ARE SHOWING THAT THE HIGH CLOUDINESS SHOULD PERSIST OVERNIGHT. WEAK HIGH PRESSURE STRETCHING ACROSS THE SOUTHEAST WILL RESULT IN LIGHT WEST WIND AFTER MIDNIGHT. THERE SHOULD BE ENOUGH LOW LEVEL MOISTURE AND LIGHT TO CALM WINDS TO WILL ALLOW PATCHY TO AREAS OF FOG TO FORM AGAIN AFTER MIDNIGHT. VISIBILITY SHOULD BE AT LOWEST TOWARD SUNRISE SUNDAY. SEA FOG AND VERY LOW CLOUD HEIGHTS ALONG THE VOLUSIA COUNTY BEACHES MAY BE A PROBLEM AGAIN AS AS COASTAL SITES FROM PONCE INLET AND NEW SMYRNA BEACH NORTH ARE REPORTING LOW CLOUDS...LESS THAN 1000 FOOT CEILINGS AND REDUCED VISIBILITY. REMOVE PRECIP FROM THE LAND/ZONES GRIDS AND STARTED FOG FORMATION EARLIER. UPDATED THE WIND...WEATHER AND SKY GRIDS. PREVIOUS ZONES DISCUSSION... TONIGHT AND SUNDAY...CU FIELD ASCD WITH A SLOW INLAND MOVING EAST COAST BREEZE BOUNDARY AND INTERACTION WITH LOCALIZED BOUNDARIES SHOULD HELP INITIATE ISOLATED SHOWERS INTO EARLY EVENING. WL KEEP COVERAGE WORDING TO ISOLATED THROUGH AROUND 10 PM WHEN ACTIVITY WINDS DOWN WHILE DRIFTING EAST TO SOUTHEAST OVER THE MARINE AREA. VERY LIGHT TO CALM WINDS WILL ALLOW FOR AREAS OF FOG TO DEVELOP ONCE AGAIN EARLY SUNDAY DURING THE EARLY MORNING HOURS. CAN`T RULE OUT SOME DENSE FOG IN SOME SPOTS BEFORE DAYBREAK AS WAS THE CASE THIS MORNING. LOWS WILL BE MILD IN THE 60S. SUNDAY...HEIGHT FALLS ALONG AN OLD SFC BOUNDARY WL DESTABILIZE AIR MASS MOST NOTABLY OVER N FL. EXPECT A CONTAINED LIGHT WLY WIND REGIME WITH SUITABLE LINGERING MOISTURE IN THE LOWER LEVELS TO HELP PRODUCE ISOLD AFTERNOON SHOWERS. PRESENCE OF A DEFINED EAST COAST BREEZE BOUNDARY AND OTHER COLLISIONS SHOULD BE KEY IN PRODUCING ISOLATED SHOWERS BY MID AFTERNOON WITH A SLOW EAST TO SOUTHEAST MOVEMENT IN WEAK WESTERLY STEERING LEVEL WINDS. AFTER BREAKING OF MORNING FOG AMPLE HEATING WILL BRING INLAND AREAS TO THE UPPER 80S WITH MID 80S ALONG THE COAST. SUN NIGHT-MON NIGHT... MID LEVEL SHORT WAVE TROUGH WILL MOVE RAPIDLY EWD FROM THE WRN GULF COAST AND LWR MS VLY ACROSS THE SERN CONUS/FL BY MON AFTERNOON. SURFACE RESPONSE IS IN THE FORM OF A PAIR OF WEAK SFC LOW PRES WAVES ALONG A FRONTAL BDRY WHICH SAGS INTO THE AREA BY MONDAY NIGHT AND THEN STALLS/BECOMES DIFFUSE. MODEL GUIDANCE LOOKS TO BE A LITTLE BIT FASTER WITH THE SYSTEM...AND AS SUCH HAVE NUDGED POPS UP ACROSS THE NORTH FOR SHRA ACTIVITY LATE SUN NIGHT. MID LEVEL DPVA COUPLED WITH BROADLY DIVGT H25 FLOW WILL YIELD SUFFICIENT FORCED ASCENT THAT WILL WORK ON INCREASING MEAN PWAT (1.5 TO 1.7") AND RESULT IN SCT-NMRS SHRA AND A FEW TS. CURRENT GRIDS BUMPED NUMBERS UP TO 50-70 PCT...AND THESE COULD GO A BIT HIGHER. MAXES ACROSS THE NORTH GNRLY IN THE U70S WITH L80S SOUTH. TUE-SAT...RELATIVELY DRY ZONAL FLOW PATTERN AT MID WEEK GRADUALLY BECOMES CYCLONIC FROM LATE THU INTO THIS WEEKEND AS A LARGE FULL LAT TROUGH DEVELOPS OVER THE ERN CONUS. THIS SPELLS INCREASING RAIN CHCS FOR LATE THU INTO FRI AHEAD OF A RATHER STRONG COLD FRONTAL PASSAGE LATE FRIDAY...THEN TURNING COOLER FROM FRI NIGHT INTO THIS WEEKEND. THROUGH FRI...MAXES IN THE U70S-NEAR 80F AT THE COAST AND L80S INLAND WITH MINS IN THE 60S. BEHIND THE FRONT....TEMPS DROPPING BACK INTO THE 70S ON SAT WITH MINS MAINLY IN THE 50S BOTH FRI/SAT NIGHTS. && .AVIATION...VFR CONDITIONS UNTIL 06Z THEN MVFR TO 13Z. AREAS OF BR WILL REDUCE VSBYS TO 3-5SM TIL 22/06Z FM 22/06Z-22/08Z LOCAL 1-2SM BR. AREAS OF 2-3SM BR WITH LCL 1/4 TO 1/2SM FG FM 22/08Z-22/13Z. && .MARINE....TONIGHT AND SUNDAY EXPECT FAVORABLE CONDS OVERNIGHT INTO SUN WITH LIGHT GRADIENT WIND CONDS AND DECREASING SWELL. SEAS 3 FT OR LESS OUTER WATERS AND AROUND 2 FT NEAR THE IMMEDIATE COAST. PREVIOUS MARINE DISCUSSION... SUN NIGHT-THU...OFFSHORE FLOW AHEAD OF WEAK FRONTAL WAVES SUN NIGHT- EARLY MON WITH FRONTAL BDRY SAGGING SOUTH TO AROUND CAPE CANAVERAL BY MONDAY NIGHT AND THEN STALLING/WASHING OUT TUE...WITH WINDS BCMG RATHER LIGHT. FLOW BEGINS TO INCREASE OUT OF THE SE-S WED AND S-W THU AHEAD OF THE NEXT SYSTEM. SOME INCREASE IN WINDS/SEAS POST FROPA MON NIGHT-TUE NIGHT WITH SWELL LINGERING WELL INTO THE WEEK. SEAS GENERALLY 3-4FT NEAR SHORE AND 4-5/4-6FT WELL OFFSHORE. && .PRELIMINARY POINT TEMPS/POPS... DAB 65 83 65 74 / 20 20 40 70 MCO 67 88 68 80 / 10 20 20 60 MLB 66 86 67 78 / 20 20 20 60 VRB 66 87 66 80 / 20 20 10 50 LEE 67 84 68 80 / 10 20 40 70 SFB 67 87 67 79 / 20 20 30 70 ORL 69 87 68 79 / 10 20 20 70 FPR 64 86 64 80 / 20 10 10 50 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ KELLY/WIMMER
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1237 AM CDT FRI MAR 20 2015 .UPDATE... 805 PM CDT FOR EVENING UPDATE... ONLY MINOR TWEAKS TO FORECAST/GRIDS THIS EVENING...MAINLY TO RAISE POP ACROSS SOUTHERN PORTIONS OF OUR SOUTHERN COUNTIES FOR LIGHT RAIN THIS EVENING. LATE AFTERNOON/EARLY EVENING WATER VAPOR IMAGERY SHOWS MID-LEVEL SHORT WAVE FEATURE MOVING INTO THE LOWER OHIO VALLEY. SURFACE MAP DOESN`T INDICATE MUCH OF A SURFACE REFLECTION WITH THIS DISTURBANCE WITH FORCING MAINLY CONCENTRATED ALONG LOW-MID LEVEL BAROCLINIC ZONE ACROSS THE LOWER MISSOURI/OHIO RIVER VALLEYS. LOCALLY...REGIONAL RADAR MOSAIC DEPICTS AN AREA OF LIGHT/EMBEDDED MODERATE RAIN GENERALLY SOUTH OF ABOUT A MACOMB-PONTIAC LINE AT 8 PM CDT...WITH MAINLY LIGHT RAIN EXPECTED ESPECIALLY ACROSS THE SOUTHERN TIER OF WFO LOT COUNTIES THROUGH THE REMAINDER OF THE EVENING...THOUGH SPOTTY LIGHT RAIN HAS BEEN REPORTED AS FAR NORTH AS PERU IL AND WILL CONTINUE TO BE POSSIBLE GENERALLY ALONG/SOUTH OF THE I-80 CORRIDOR. OVERALL...THE GOING FORECAST HANDLES THIS WELL IN BOTH SPACE AND TIME AND ONLY REAL CHANGE WAS TO INCREASE POPS TO LIKELIES OVER THE SOUTHERN PARTS OF LIVINGSTON...FORD AND IROQUOIS AS WELL AS BENTON COUNTIES. GUIDANCE IN PRETTY GOOD AGREEMENT IN DECREASING RAIN COVERAGE FROM THE WEST DURING THE PREDAWN HOURS...AND ENDING PRIOR TO SUNRISE AS PHASING/AMPLIFYING NORTHERN STREAM UPPER TROUGH MOVES THROUGH. OTHERWISE...FORECAST IN GOOD SHAPE...WITH ONLY MINIMAL HOURLY TEMP/DEW POINT AND WIND GRID TWEAKS BASED ON HOURLY OBSERVATIONAL TRENDS EARLY THIS EVENING. RATZER && .SHORT TERM... 243 PM CDT THROUGH SATURDAY... MAIN FORECAST CONCERNS IN THE NEAR TERM INCLUDE PRECIP CHANCES IN OUR SOUTHERN COUNTIES TONIGHT...AND A COLD FRONT WHICH WILL BRING FALLING TEMPERATURES DURING THE DAY SATURDAY... RADAR IMAGERY SHOWS AREA OF PRECIPITATION ACROSS PORTIONS OF NORTHERN MISSOURI AND WEST CENTRAL ILLINOIS THIS AFTERNOON ASSOCIATED WITH AN AREA OF WARM ADVECTION AND BROAD MID-LEVEL HEIGHT FALLS IN ADVANCE OF A LOW AMPLITUDE WAVE. THIS AREA WILL SPREAD ENE ACROSS PORTIONS OF MAINLY CENTRAL ILLINOIS THIS EVENING AND TONIGHT...WITH THE BEST CHANCES FOR PRECIP STAYING SOUTH OF I-80 IN THE LOCAL FORECAST AREA. EXPECT THE ENTIRE FORECAST AREA TO BE DRY ON FRIDAY AS SUBSIDENCE OVERSPREADS THE REGION BEHIND THE DEPARTING UPPER TROUGH. DOWN LOW...WINDS TURN SOUTHWEST IN ADVANCE OF OUR NEXT SYSTEM HELPING TO ADVECT IN WARMER TEMPERATURES. MID TO UPPER 50S ARE EXPECTED FRIDAY AFTERNOON. SOUTHWEST FLOW SHOULD REMAIN STRONG ENOUGH TO PREVENT A LAKE BREEZE FROM MAKING MUCH IF ANY INLAND PROGRESS TOMORROW. MEANWHILE...LOW PRESSURE TRACKING ACROSS HUDSON BAY INTO THE CANADIAN MARITIME PROVINCES TOMORROW WILL DRAG A COLD FRONT INTO THE NORTHERN GREAT LAKES REGION WITH A WAVE FORMING ALONG THE FRONT IN THE UPPER MIDWEST AS ANOTHER SHORTWAVE TROUGH DIVES INTO THE NORTHERN TIER OF STATES. PRECIPITATION WITH THIS SYSTEM SHOULD REMAIN WELL TO OUR NORTH WITH PRETTY DRY CONDITIONS NOTED IN THE SOUNDINGS LOCALLY. DO EXPECT HOWEVER THAT THE COLD AIR BEHIND THE FRONT WILL SURGE DOWN LAKE MICHIGAN PUSHING INTO NORTHERN ILLINOIS EARLY IN THE DAY SATURDAY RESULTING IN EARLY HIGH TEMPS AND FALLING TEMPS OFF THE LAKE BY AROUND MIDDAY. DEUBELBEISS && .LONG TERM... 243 PM CDT SATURDAY NIGHT THROUGH THURSDAY... RIDGE OF HIGH PRESSURE WILL BE IN PLACE JUST TO OUR NORTH SATURDAY NIGHT INTO SUNDAY WITH A WEAK SURFACE LOW OVER THE CENTRAL PLAINS AND THE LOCAL FORECAST AREA JUST ON THE COLD SIDE OF THE H85 BAROCLINIC ZONE. OVERNIGHT LOWS SHOULD FALL BELOW FREEZING AREA WIDE SATURDAY NIGHT WITH TEMPERATURES ONLY REBOUNDING INTO THE 40S SUNDAY. ISENTROPIC ASCENT INCREASES THROUGH THE DAY SUNDAY FOCUSED FROM SOUTHERN MINNESOTA INTO NORTHERN ILLINOIS. WITH ANTECEDENT DRY LOW LEVELS AND DRY NORTHEASTERLY FLOW ALSO IN THE LOW LEVELS...LEANING TOWARDS SLOWER GUIDANCE AS FAR AS OSNET OF PRECIPITATION SO EXPECT SUNDAY TO BE DRY ACROSS THE FORECAST AREA WITH PRECIP CHANCES INCREASING FROM THE NORTHWEST LATE SUNDAY NIGHT INTO MONDAY AS A COMPACT VORT MAX DROPS INTO THE MIDWEST. DESPITE SURFACE TEMPERATURES EVENTUALLY RISING INTO THE MID TO UPPER 30S MONDAY...THE DEPTH OF THE NEAR SURFACE WARM LAYER MAY BE TOO SHALLOW FOR COMPLETE MELTING SO EXPECT PRECIPITATION TO PRIMARILY FALL AS SNOW. LIGHT ACCUMULATIONS APPEAR POSSIBLE HOWEVER DIFFERENCES IN THE TRACK PRECLUDE NAILING DOWN ANY OF THE DETAILS THIS FAR OUT...BUT WOULD PROBABLY ERR ON THE DRIER SIDE GIVEN SOME OF THE AFOREMENTIONED CONCERNS ABOUT MOISTURE AVAILABILITY AND SATURATION CONCERNS. CONTINUE TO MONITOR THE POSSIBILITY OF A MORE DYNAMIC SYSTEM IMPACTING THE REGION TUESDAY AND WEDNESDAY WITH MODELS CONTINUING TO ADVERTISE AT LEAST A BRIEF WARMUP THANKS TO 50KT+ LOW LEVEL JET TRANSPORTING +10C 850MB TEMPS AND PWATS JUST IN EXCESS OF AN INCH INTO PORTIONS OF THE UPPER MIDWEST. LATEST GFS AND ECMWF BOTH SHOW THE THERMAL AXIS MOVING ACROSS NORTHERN ILLINOIS TUESDAY NIGHT. BASED ON CURRENT TIMING OFF THE ECMWF AND GFS...WOULD EXPECT WARMING TEMPS TUESDAY NIGHT AND CONSERVATIVELY MID TO UPPER 50S WEDNESDAY...THOUGH GUIDANCE MAY BE UNDER-FORECASTING THE WARMUP. PRECIPITATION...CLOUD COVER...AND TIMING OF THE COLD FRONT WILL LIKELY BE LIMITING FACTORS BUT CLIMATOLOGY SUGGESTS WE COULD EASILY BE ABLE TO GET INTO THE 60S WEDNESDAY. COLD FRONT EVENTUALLY SWEEPS BACK ACROSS THE REGION MIDWEEK WITH WELL BELOW NORMAL CONDITIONS RETURNING THE LATTER HALF OF NEXT WEEK. DEUBELBEISS && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * NONE. KJB //DISCUSSION...UPDATED 06Z... A SURFACE FRONTAL TROUGH OF LOW PRESSURE WILL GRADUALLY SHIFT EAST- SOUTHWARD ACROSS THE UPPER MIDWEST LATER TODAY. THIS WILL DRIVE PRIMARILY SOUTHWEST FLOW ACROSS THE TERMINALS TODAY...WITH SOME LOW END GUSTS UP TO 20 KT EVENING LOOKING LIKELY BY THIS AFTERNOON. SUSTAINED WIND SPEEDS COULD REMAIN ELEVATED OUT OF THE SOUTHWEST THROUGH THIS EVENING...DUE IN LARGE PART TO A CORRIDOR OF GOOD PRESSURE FALLS SETTING UP TO OUR NORTHEAST OVER LOWER MICHIGAN AHEAD OF THE APPROACHING TROUGH DURING THE EVENING HOURS. WE COULD EVEN SEE A BIT OF AN INCREASE IN THE SOUTHWEST WINDS DURING THE EVENING. LOW LEVEL WIND SHEAR IS POSSIBLE OVER THE AREA LATER THIS EVENING AS WINDS OFF THE DECK COULD INCREASE TO OR JUST IN EXCESS OF 40 KT. HOWEVER...DUE TO THE FACT THAT SURFACE WINDS COULD ALSO BE OF DECENT MAGNITUDE...AND IT COULD END UP BEING SHORT LIVED...I HAVE HELD OFF ON INCLUDING ANY WIND SHEAR IN THE TAFS AT THIS TIME. OTHERWISE VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. A COLD FRONT WILL BE APPROACHING NORTHERN ILLINOIS BY EARLY SATURDAY MORNING. THERE REMAINS UNCERTAINTY ON THE EXACT TIMING OF THIS FRONTAL PASSAGE...WITH SOME POSSIBILITIES OF IT NOT PASSING OVER THE TERMINALS UNTIL AROUND DAYBREAK SATURDAY. NORTH-NORTHEASTERLY WINDS WILL SET UP IN THE WAKE OF THIS FRONT. GIVEN THE TIMING UNCERTAINTIES...I HAVE NOT INCLUDED THIS WINDS SHIFT IN THE NEW 30 HOUR ORD TAF DUE TO THE FACT THAT IT MAY OCCUR JUST PAST THE END OF THIS PERIOD. KJB //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE IN ALL FORECAST ELEMENTS. KJB //OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z... SATURDAY AND SUNDAY...VFR SUNDAY NIGHT AND MONDAY...CHANCE OF RAIN OR SNOW. IFR POSSIBLE. TUESDAY...VFR. TUESDAY NIGHT AND WEDNESDAY...CHANCE OF RAIN. IFR POSSIBLE IZZI && .MARINE... 203 PM CDT AS HIGH PRESSURE CONTINUES TO MOVE FROM THE EASTERN GREAT LAKES TO THE EAST...GENERALLY SELY HAS DEVELOPED OVER LAKE MICHIGAN. A WEAK GRADIENT OVER THE SOUTHERN PORTIONS OF THE LAKE HAVE ALLOWED A PSEUDO-LAKE BREEZE TO DEVELOP WITH WINDS MORE ELY OVER THE NEARSHORE WATERS ALONG THE ILLINOIS COAST...WHILE WINDS REMAIN SELY OVER THE INDIANA NEARSHORE WATERS. AS THE HIGH CONTINUES TO THE EAST TONIGHT AND LOW PRESSURE TRACKS ACROSS THE CANADIAN PRAIRIES...WITH A TRAILING COLD FRONT EXTENDING INTO THE NRN PLAINS...WINDS WILL VEER TO SOUTHERLY BY FRIDAY MORNING. THE COMBINATION OF A SLOW MOVING HIGH MOVING OFF TO THE EAST AND A FASTER MOVING SFC TROUGH AND ASSOCIATED COLD FRONT FROM THE WEST...WILL LEAD TO STRENGTHENING SLY WINDS THROUGH FRIDAY INTO FRIDAY EVENING WITH SPEEDS INCREASING TO 20-25KT...WITH THE STRONGEST WINDS OVER THE NRN PORTIONS OF THE LAKE WHERE THE GRADIENT WILL BE STRONGEST. THE COLD FRONT IS EXPECTED TO PUSH SOUTH DOWN THE LAKE LATE FRIDAY NIGHT...INTO SATURDAY MORNING...TURNING WINDS MORE NORTHERLY AND DRAWING COLDER AIR DOWN THE LAKE. THE INCREASING COLD ADVECTION AS ANOTHER ARCTIC HIGH BUILDS OUT OF CANADA AND INTO THE UPPER MISSISSIPPI VALLEY AND WESTERN GREAT LAKES SHOULD HELP BRING THE NORTHERLY WINDS BACK UP TO 20-25KT SATURDAY NIGHT AND INTO SUNDAY. WHILE GALES ARE NOT EXPECTED FOLLOWING THE FRONTAL PASSAGE...THE EXTENDED NORTHERLY FETCH SHOULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS FOR BOTH THE ILLINOIS AND INDIANA NEARSHORE WATERS FOR SATURDAY NIGHT AND SUNDAY. WINDS WILL GRADUALLY VEER TO NORTHEASTERLY TO EASTERLY SUNDAY NIGHT AND MONDAY AS THE HIGH BUILDS ACROSS THE EASTERN GREAT LAKES AND WEAK LOW PRESSURE DEVELOPING OVER THE CENTRAL PLAINS SUNDAY TRACKS EAST TO THE LOWER OHIO VALLEY BEFORE WEAKENING TO AN OPEN TROUGH EXTENDING FROM TENNESSEE TO WESTERN PENNSYLVANIA EARLY NEXT WEEK. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1123 PM CDT Thu Mar 19 2015 .UPDATE... ISSUED AT 832 PM CDT THU MAR 19 2015 Shortwave trof seen on the Water Vapor loop this evening over western Minnesota thru central Nebraska has brought rain through all but our far southeast counties. Looks like several more hours of light rain over our central and northern counties this evening into the early morning hours before the trof shifts closer to our area by Friday morning. May see some lingering light rain over our far eastern counties early Friday morning but it appears the bulk of the precip will be east of our area by dawn Friday with surface winds turning more into a westerly direction which will bring in some drier air for the remainder of the day. May take some time to scour out the low level clouds in the morning but as winds back more into a west to southwest direction for the afternoon, we should see the sun return helping to push temperatures back into the mid and upper 50s. Have made some adjustments to POPs, mainly across our central and northern counties, along with the usual early evening temperature tweaks to the grids. Should have the updated zones out by 900 pm. && .SHORT TERM...(Tonight) ISSUED AT 209 PM CDT THU MAR 19 2015 Area of rain across Missouri has spread into west central Illinois early this afternoon, with some light rain being reported as far east as Jacksonville at 2 pm. Still quite a bit of dry air underneath this rain, with temp/dew point spreads around 15 degrees, so amounts will remain rather light this afternoon. Latest HRRR and NAM spread this eastward centered along the Jacksonville-Paris corridor through the afternoon, reaching the Indiana border toward 4-5 pm., with a southern extent generally along I-70. Any northward extension past Peoria would be more likely very late afternoon. The bulk of the precipitation should be east of the forecast area by around midnight or so, but some drizzle is likely to linger overnight, especially in the south half of the forecast area, where stratus should become extensive after midnight. Little change made to the temperatures, with lows 35-38 in most areas. && .LONG TERM...(Friday through Thursday) ISSUED AT 209 PM CDT THU MAR 19 2015 Split-flow pattern continues into the end of the week as deep trough continues to pivot over the Hudson Bay area and southern stream energy moves slowly over the southwest U.S.. Wave embedded in the northern stream trough should exit the forecast area Friday bringing gradual clearing and seasonal temperatures. Next northern stream wave and associated cold front is expected to impact the area on Saturday. Significant spread on frontal passage timing is evident in operational model suite and SREF which has major implications on temperatures for Saturday, particularly across the central forecast area. Northern tier of area see passage before peak heating in most of the solutions with I-70 southward not impacted by cold advection until well after peak heating through the solution envelope. Its the I-72/Danville corridor which has the largest impact of this difference in timing. Operational 12Z NAM is slow enough to suggest some lower 70s are possible across southwest forecast area, however, the model seems to be on the warm side of the SREF envelope. For now will be leaning toward the cooler, but still above normal, GFS/SREF Mean timing. Either way, moisture remains shunted south and east of Illinois so passage will be dry. Much cooler temperatures will move into the region behind the front with progged 850 mb temps expected below freezing across the northern half of the area by Monday. Models are suggesting a temporary transition to a more progressive zonal pattern by early next week. The initial wave in this pattern shift is progged to move eastward into Illinois Monday. Low-level temperatures remain cool and Bufkit soundings suggest a mix of precip may be possible late Sunday Night and early Monday across northern portions of the forecast area. The southern stream energy moving across the southern tier of the country is expected to be over the eastern Gulf of Mexico by Sunday Night shunting any Gulf moisture east limiting moisture available in the Midwest, so QPF will likely be limited to a few tenths of liquid at most. Phased ridging develops over the Mississippi Valley by Tuesday allowing temps to respond rapidly. With the phasing, Gulf moisture is available for the next wave expected to push into the state on Wednesday. Latest model suite are fairly consistent on bringing 850 temps into the 10C range with surface dew points into the 50s. Timing of the waves associated cold front will have an impact on any potential instability and if a passage does occur near peak heating can not rule out the potential for thunder, particularly across southeast Illinois Wednesday afternoon and evening. At this time, GFS and ECMWF suggest the strong wave on Wednesday will assist in a transition back to a ridge west/trough east longwave pattern allowing cold air to once again plummet into the midwest. With 850 mb temps expected to be below 0C by Thursday afternoon, highs on Thursday may struggle to make it out of the 40s. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) ISSUED AT 1115 PM CDT THU MAR 19 2015 Backedge of rain continues to push steadily to the east and was about to push east of PIA. Most of the steadier light rain should be east of our TAF sites between 07z-09z. We may see some light drizzle at times during the early morning hours as the lower levels of the atmosphere continues to saturate ahead of an upper level disturbance, which should pass east of our area Friday morning. Until then, latest short term forecasts continue to suggest the cigs will continue to lower to IFR. With the trof axis still to our west and the very light surface flow expected to continue thru about 15z Friday, can not rule that out so will continue to include at least some tempo IFR groups into the morning hours. Forecast soundings indicate a gradual improvement to VFR but not until after 17z across our eastern TAF sites as the low level westerly flow starts to increase. The light and variable wind regime will continue for the rest of the night and then start to increase from a westerly direction after 13z Friday with speeds by afternoon in the 10 to 15 kt range. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Smith SHORT TERM...Geelhart LONG TERM...Barker AVIATION...Smith
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1108 PM EDT SAT MAR 21 2015 .UPDATE... ISSUED AT 1100 PM EDT SAT MAR 21 2015 HOURLY GRIDS HAVE BEEN UPDATED TO ACCOUNT FOR THE LATEST OBSERVATIONS AND THE DRY COLD FRONT CROSSING THE AREA. THIS FRONTAL PASSAGE SHOULD LEAD TO ENOUGH MIXING OF THE DECOUPLED VALLEYS IN THE SOUTHEAST FOR AT LEAST A COUPLE OF HOURS AS IT MOVES THROUGH...BEFORE TEMPS AGAIN DROP OFF LATE TONIGHT BEHIND THE FRONT. THE HOURLY TEMPERATURES HAVE BEEN BLENDED TO THE PREVIOUS CURVED AFTER 3 AM TO ACCOUNT FOR THIS EXPECTATION. UPDATE ISSUED AT 810 PM EDT SAT MAR 21 2015 HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND SATELLITE IMAGERY. THE COLD FRONT THAT IS LACKING IN LOW LEVEL MOISTURE IS DROPPING INTO THE NORTHERN PART OF THE CWA ATTM. THIS FRONT WILL DROP SOUTH ACROSS THE REMAINDER OF THE CWA DURING THE REST OF THIS EVENING AND INTO THE OVERNIGHT HOURS. THIS FRONT WILL BRING LITTLE MORE THAN A SHIFT IN WINDS FROM THE WEST OR SOUTHWEST TO THE NORTH AND NORTHEAST ON RIDGETOPS AND IN EXPOSED LOCATIONS. CIRRUS ASSOCIATED WITH A SHORTWAVE WORKING FROM THE SOUTHERN PLAINS TOWARD THE MS VALLEY REGION CONTINUES TO MOVE OVERHEAD AS IT WORKS AROUND RIDGING EXTENDING FROM THE GULF OF MEXICO INTO THE SOUTHEAST. THERE IS ADDITIONAL CIRRUS PASSING BY IN THE WEST TO NORTHWEST FLOW ALOFT. CLOUD COVER WAS INCREASED OVERNIGHT INTO SUNDAY AS THE CIRRUS HAS BEEN RATHER THICK AND MODELS INDICATE IT MAY GET THICKER. SOME MID CLOUDS WILL ALSO PASS BY FROM TIME TO TIME ON SUNDAY AS THE SHORTWAVE EJECTS INTO THE SOUTHEASTERN STATES. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM EDT SAT MAR 21 2015 18Z SFC ANALYSIS SHOWS HIGH PRESSURE NOSING DEEPER INTO EAST KENTUCKY KEEPING THE SKIES MOSTLY CLEAR...ASIDE FROM A SOME HIGH CLOUDS SEEPING NORTH FROM LOW PRESSURE WELL TO THE SOUTHWEST OF THE AREA. DESPITE THE HIGH PRESSURE AND RETURNING SUNSHINE... DEWPOINTS REMAIN IN THE UPPER 30S AND LOWER 40S KEEPING THE RH AROUND 50 PERCENT FOR MUCH OF THE AREA. MEANWHILE...TEMPERATURES ARE STILL CATCHING UP TO FORECAST HIGHS WITH A COUPLE OF HOURS OF CLIMBING YET TO GO...RANGING FROM LOW 60S IN THE SOUTH TO THE MID 50S IN THE NORTH. WINDS ARE GENERALLY LIGHT FROM THE SOUTHWEST... THOUGH ON THE NORTHEAST FRINGE OF THE HIGH PRESSURE SYSTEM THERE HAVE BEEN A FEW GUSTS TO BETWEEN 15 AND 20 KTS. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY DEPICT SOUTHERN STREAM ENERGY BRUSHING BY KENTUCKY SUNDAY INTO MONDAY AS A BROAD TROUGH SLOWLY MOVES THROUGH THE LOWER MISSISSIPPI VALLEY AND DEEP SOUTH. DURING THIS TIME...EASTERN KENTUCKY WILL BE IN THE MIDST OF GENERALLY BENIGN NORTHWEST FLOW IN WHICH ANY NORTHERN STREAM ENERGY STAYS OFF TO THE NORTHEAST OF THE AREA. HEIGHTS DO FALL A BIT TONIGHT INTO SUNDAY...BUT NOT DRAMATICALLY ENOUGH TO HAVE MUCH IMPACT ON SENSIBLE WEATHER. GIVEN THE MODEL AGREEMENT...HAVE FAVORED THE HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS THROUGH MONDAY MORNING. SENSIBLE WEATHER WILL FEATURE A COOL NIGHT DESPITE THE HIGH CLOUDS DRIFTING IN FROM THE SOUTHWEST FROM A WEAK LOW NEAR THE CENTRAL GULF COAST. AT THE SAME TIME...A COLD FRONT WILL SLIP INTO AND THROUGH THE AREA WITH NOT MUCH IN THE WAY OF MOISTURE. EXPECTING A DECENT START TO THE NIGHT FOR DECOUPLING AND RADIATIONAL COOLING SO HAVE BROUGHT THE VALLEY TEMPS DOWN QUICKER THAN THE MODELS WOULD SUGGEST. THE COLDER SPOTS MIX OUT IN THE MORNING UNDER PARTIAL SUNSHINE SUNDAY WITH TEMPERATURES TOPPING OUT A CATEGORY OR TWO BELOW TODAY/S HIGHS. WITH THE FRONT SOUTH OF THE AREA FOR SUNDAY NIGHT WE WILL SEE SOME COLDER TEMPERATURES ACROSS THE BOARD WITH SOME MINOR RIDGE TO VALLEY DIFFERENCES BY DAWN. FOR TONIGHT...PATCHY FOG CAN BE EXPECTED IN THE VALLEYS TOWARD DAWN WHILE ON SUNDAY NIGHT THERE MAY BE SOME PATCHES OF FROST IN THE VALLEYS. HAVE LEFT THE FROST OUT OF THE ZFP FORECAST FOR NOW...BUT DID ADD SOME TO THE GRIDS. AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO SUNDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD. AS FOR POPS...KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 235 PM EDT SAT MAR 21 2015 THE UPCOMING WEEK WILL FEATURE A TRANSITION FROM MEAN ZONAL FLOW EARLY IN THE PERIOD TO A HIGHLY AMPLIFIED PATTERN BY THE END OF THE PERIOD...WITH A DEEP TROUGH BECOMING ESTABLISHED IN THE EASTERN UNITED STATES WITH A RIDGE IN THE WEST. THIS WILL RESULT IN A SIGNIFICANT COOL DOWN AS WE HEAD INTO NEXT WEEKEND. THE START OF THE FORECAST PERIOD WILL FEATURE A SHORT WAVE MOVING THROUGH THE SOUTHERN STREAM ACROSS THE SOUTHEAST U.S. AND THEN OFF THE ATLANTIC COAST. A WEAK SYSTEM WILL ALSO BE PASSING BY TO OUR NORTH. OTHER THAN INCREASED CLOUDINESS THERE SHOULD BE LITTLE IMPACT TO OUR AREA FROM THESE SYSTEMS. AS WE MOVE INTO MID WEEK A MUCH MORE SIGNIFICANT SHORT WAVE WILL EMERGE INTO THE PLAINS. OUT AHEAD OF THIS...A SURFACE WARM FRONT WILL MOVE ACROSS THE REGION WITH A SIGNIFICANT SURGE OF WARM AIR MOVING INTO THE AREA AHEAD OF AN ADVANCING COLD FRONT. AS THE UPPER SYSTEM AND SURFACE LOW MOVE INTO THE GREAT LAKES REGION THE COLD FRONT WILL MOVE INTO ERN KY WEDNESDAY NIGHT INTO THURSDAY. THIS WILL BRING A GOOD CHANCE OF RAIN...WITH COOLER TEMPERATURES FOLLOWING. HAVE DECIDED TO ADD A SLIGHT CHANCE OF THUNDER WITH THIS FRONTAL PASSAGE AS WELL..WHICH WILL BE IN GOOD AGREEMENT WITH WFOS TO OUR WEST AND SOUTH. A SECOND SURGE OF COLDER AIR LOOKS TO IMMEDIATELY FOLLOW THE INITIAL COLD FRONTAL PASSAGE...AND THE POSSIBILITY EXISTS FOR SOME SNOW TO AT LEAST MIX IN WITH RAIN IF ANY PRECIPITATION LINGERS INTO FRIDAY NIGHT. THE OPERATIONAL GFS IS THE MOST AGGRESSIVE MODEL WITH THE COLD AIR SURGE...WITH THE ECMWF AND GFS ENSEMBLE MEAN...WHILE STILL COLD...NOT AS IMPRESSIVE...WITH 85H TEMPERATURES 5 DEGREES OR SO WARMER. AT THIS POINT THERE IS STILL CONSIDERABLE UNCERTAINTY REGARDING THE WEATHER DETAILS FOR THE END OF THE WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 820 PM EDT SAT MAR 21 2015 ALTHOUGH A COLD FRONT IS DROPPING SOUTH INTO THE AREA ATTM...IT IS LACKING IN LOW LEVEL MOISTURE. THERE WILL BE A WIND SHIFT FROM THE WEST OR SOUTHWEST TO THE NORTH AND NORTHEAST AS IT PASSES A LOCATION BY WINDS SHOULD AVERAGE 6KT OR LESS. VALLEY LOCATIONS SUCH AS SME AND LOZ MAY BE DECOUPLED AND NOT EXPERIENCE THIS WITH ONLY LIGHT AND VARIABLE WINDS. A TOUCH OF GENERALLY MVFR VALLEY FOG IS POSSIBLE AFTER THE 6Z TO 9Z PERIOD AND THIS HAS BEEN INCLUDED AT SME AS SUGGESTED BY SOME OF THE RECENT LAMP GUIDANCE AND PERSISTENCE FROM THE PREVIOUS TAF. OUTSIDE OF ANY VALLEY FOG VFR IS EXPECTED DURING THE PERIOD AS CLOUDS FROM 12Z TO 0Z SHOULD ALSO BE JUST CIRRUS AND SOME MID LEVEL CLOUDS. WINDS DURING THE LAST 12 HOURS OF THE PERIOD SHOULD ALSO BE 5KT OR LESS AND VARIABLE OUT OF THE NORTH TO NORTHEAST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...SBH AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
845 PM EDT SAT MAR 21 2015 .UPDATE... ISSUED AT 810 PM EDT SAT MAR 21 2015 HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND SATELLITE IMAGERY. THE COLD FRONT THAT IS LACKING IN LOW LEVEL MOISTURE IS DROPPING INTO THE NORTHERN PART OF THE CWA ATTM. THIS FRONT WILL DROP SOUTH ACROSS THE REMAINDER OF THE CWA DURING THE REST OF THIS EVENING AND INTO THE OVERNIGHT HOURS. THIS FRONT WILL BRING LITTLE MORE THAN A SHIFT IN WINDS FROM THE WEST OR SOUTHWEST TO THE NORTH AND NORTHEAST ON RIDGETOPS AND IN EXPOSED LOCATIONS. CIRRUS ASSOCIATED WITH A SHORTWAVE WORKING FROM THE SOUTHERN PLAINS TOWARD THE MS VALLEY REGION CONTINUES TO MOVE OVERHEAD AS IT WORKS AROUND RIDGING EXTENDING FROM THE GULF OF MEXICO INTO THE SOUTHEAST. THERE IS ADDITIONAL CIRRUS PASSING BY IN THE WEST TO NORTHWEST FLOW ALOFT. CLOUD COVER WAS INCREASED OVERNIGHT INTO SUNDAY AS THE CIRRUS HAS BEEN RATHER THICK AND MODELS INDICATE IT MAY GET THICKER. SOME MID CLOUDS WILL ALSO PASS BY FROM TIME TO TIME ON SUNDAY AS THE SHORTWAVE EJECTS INTO THE SOUTHEASTERN STATES. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM EDT SAT MAR 21 2015 18Z SFC ANALYSIS SHOWS HIGH PRESSURE NOSING DEEPER INTO EAST KENTUCKY KEEPING THE SKIES MOSTLY CLEAR...ASIDE FROM A SOME HIGH CLOUDS SEEPING NORTH FROM LOW PRESSURE WELL TO THE SOUTHWEST OF THE AREA. DESPITE THE HIGH PRESSURE AND RETURNING SUNSHINE... DEWPOINTS REMAIN IN THE UPPER 30S AND LOWER 40S KEEPING THE RH AROUND 50 PERCENT FOR MUCH OF THE AREA. MEANWHILE...TEMPERATURES ARE STILL CATCHING UP TO FORECAST HIGHS WITH A COUPLE OF HOURS OF CLIMBING YET TO GO...RANGING FROM LOW 60S IN THE SOUTH TO THE MID 50S IN THE NORTH. WINDS ARE GENERALLY LIGHT FROM THE SOUTHWEST... THOUGH ON THE NORTHEAST FRINGE OF THE HIGH PRESSURE SYSTEM THERE HAVE BEEN A FEW GUSTS TO BETWEEN 15 AND 20 KTS. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY DEPICT SOUTHERN STREAM ENERGY BRUSHING BY KENTUCKY SUNDAY INTO MONDAY AS A BROAD TROUGH SLOWLY MOVES THROUGH THE LOWER MISSISSIPPI VALLEY AND DEEP SOUTH. DURING THIS TIME...EASTERN KENTUCKY WILL BE IN THE MIDST OF GENERALLY BENIGN NORTHWEST FLOW IN WHICH ANY NORTHERN STREAM ENERGY STAYS OFF TO THE NORTHEAST OF THE AREA. HEIGHTS DO FALL A BIT TONIGHT INTO SUNDAY...BUT NOT DRAMATICALLY ENOUGH TO HAVE MUCH IMPACT ON SENSIBLE WEATHER. GIVEN THE MODEL AGREEMENT...HAVE FAVORED THE HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS THROUGH MONDAY MORNING. SENSIBLE WEATHER WILL FEATURE A COOL NIGHT DESPITE THE HIGH CLOUDS DRIFTING IN FROM THE SOUTHWEST FROM A WEAK LOW NEAR THE CENTRAL GULF COAST. AT THE SAME TIME...A COLD FRONT WILL SLIP INTO AND THROUGH THE AREA WITH NOT MUCH IN THE WAY OF MOISTURE. EXPECTING A DECENT START TO THE NIGHT FOR DECOUPLING AND RADIATIONAL COOLING SO HAVE BROUGHT THE VALLEY TEMPS DOWN QUICKER THAN THE MODELS WOULD SUGGEST. THE COLDER SPOTS MIX OUT IN THE MORNING UNDER PARTIAL SUNSHINE SUNDAY WITH TEMPERATURES TOPPING OUT A CATEGORY OR TWO BELOW TODAY/S HIGHS. WITH THE FRONT SOUTH OF THE AREA FOR SUNDAY NIGHT WE WILL SEE SOME COLDER TEMPERATURES ACROSS THE BOARD WITH SOME MINOR RIDGE TO VALLEY DIFFERENCES BY DAWN. FOR TONIGHT...PATCHY FOG CAN BE EXPECTED IN THE VALLEYS TOWARD DAWN WHILE ON SUNDAY NIGHT THERE MAY BE SOME PATCHES OF FROST IN THE VALLEYS. HAVE LEFT THE FROST OUT OF THE ZFP FORECAST FOR NOW...BUT DID ADD SOME TO THE GRIDS. AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO SUNDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD. AS FOR POPS...KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 235 PM EDT SAT MAR 21 2015 THE UPCOMING WEEK WILL FEATURE A TRANSITION FROM MEAN ZONAL FLOW EARLY IN THE PERIOD TO A HIGHLY AMPLIFIED PATTERN BY THE END OF THE PERIOD...WITH A DEEP TROUGH BECOMING ESTABLISHED IN THE EASTERN UNITED STATES WITH A RIDGE IN THE WEST. THIS WILL RESULT IN A SIGNIFICANT COOL DOWN AS WE HEAD INTO NEXT WEEKEND. THE START OF THE FORECAST PERIOD WILL FEATURE A SHORT WAVE MOVING THROUGH THE SOUTHERN STREAM ACROSS THE SOUTHEAST U.S. AND THEN OFF THE ATLANTIC COAST. A WEAK SYSTEM WILL ALSO BE PASSING BY TO OUR NORTH. OTHER THAN INCREASED CLOUDINESS THERE SHOULD BE LITTLE IMPACT TO OUR AREA FROM THESE SYSTEMS. AS WE MOVE INTO MID WEEK A MUCH MORE SIGNIFICANT SHORT WAVE WILL EMERGE INTO THE PLAINS. OUT AHEAD OF THIS...A SURFACE WARM FRONT WILL MOVE ACROSS THE REGION WITH A SIGNIFICANT SURGE OF WARM AIR MOVING INTO THE AREA AHEAD OF AN ADVANCING COLD FRONT. AS THE UPPER SYSTEM AND SURFACE LOW MOVE INTO THE GREAT LAKES REGION THE COLD FRONT WILL MOVE INTO ERN KY WEDNESDAY NIGHT INTO THURSDAY. THIS WILL BRING A GOOD CHANCE OF RAIN...WITH COOLER TEMPERATURES FOLLOWING. HAVE DECIDED TO ADD A SLIGHT CHANCE OF THUNDER WITH THIS FRONTAL PASSAGE AS WELL..WHICH WILL BE IN GOOD AGREEMENT WITH WFOS TO OUR WEST AND SOUTH. A SECOND SURGE OF COLDER AIR LOOKS TO IMMEDIATELY FOLLOW THE INITIAL COLD FRONTAL PASSAGE...AND THE POSSIBILITY EXISTS FOR SOME SNOW TO AT LEAST MIX IN WITH RAIN IF ANY PRECIPITATION LINGERS INTO FRIDAY NIGHT. THE OPERATIONAL GFS IS THE MOST AGGRESSIVE MODEL WITH THE COLD AIR SURGE...WITH THE ECMWF AND GFS ENSEMBLE MEAN...WHILE STILL COLD...NOT AS IMPRESSIVE...WITH 85H TEMPERATURES 5 DEGREES OR SO WARMER. AT THIS POINT THERE IS STILL CONSIDERABLE UNCERTAINTY REGARDING THE WEATHER DETAILS FOR THE END OF THE WEEK. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 820 PM EDT SAT MAR 21 2015 ALTHOUGH A COLD FRONT IS DROPPING SOUTH INTO THE AREA ATTM...IT IS LACKING IN LOW LEVEL MOISTURE. THERE WILL BE A WIND SHIFT FROM THE WEST OR SOUTHWEST TO THE NORTH AND NORTHEAST AS IT PASSES A LOCATION BY WINDS SHOULD AVERAGE 6KT OR LESS. VALLEY LOCATIONS SUCH AS SME AND LOZ MAY BE DECOUPLED AND NOT EXPERIENCE THIS WITH ONLY LIGHT AND VARIABLE WINDS. A TOUCH OF GENERALLY MVFR VALLEY FOG IS POSSIBLE AFTER THE 6Z TO 9Z PERIOD AND THIS HAS BEEN INCLUDED AT SME AS SUGGESTED BY SOME OF THE RECENT LAMP GUIDANCE AND PERSISTENCE FROM THE PREVIOUS TAF. OUTSIDE OF ANY VALLEY FOG VFR IS EXPECTED DURING THE PERIOD AS CLOUDS FROM 12Z TO 0Z SHOULD ALSO BE JUST CIRRUS AND SOME MID LEVEL CLOUDS. WINDS DURING THE LAST 12 HOURS OF THE PERIOD SHOULD ALSO BE 5KT OR LESS AND VARIABLE OUT OF THE NORTH TO NORTHEAST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...SBH AVIATION...JP
AREA FORECAST DISCUSSION
NWS PADUCAH KY
411 PM CDT FRI MAR 20 2015 .UPDATE... ISSUED AT 411 PM CDT FRI MAR 20 2015 UPDATED AVIATION SECTION. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 1249 PM CDT FRI MAR 20 2015 LOW LEVEL TRAJECTORIES NOT FAVORABLE FOR RAPID CLEAR OUT...BUT SLOWLY OVER TIME...HIGH PRESSURE WORKS IN AND ACROSS THE TENNESSEE VALLEY AND OVERALL SUBSIDENCE/DRYING THROUGH THE COLUMN SHOULD WIN OUT...CERTAINLY...BY TMRW. THIS WILL RESULT IN A NICE WARMUP WITH TEMPS CLIMBING THRU THE 60S AND FLIRTING WITH/REACHING TOWARD 70 ESP ACROSS OUR SOUTH/WEST. A MORE OR LESS ZONAL FLOW THEN RIDES OUT THE REMAINDER OF THE SHORT TERM AND CARRIES THE FORECAST THRU THE WEEKEND. ENERGY IN THE FLOW PATTERN TO OUR NORTH AND SOUTH MEANS MORE CLOUDS SUNDAY THAN SATURDAY...AND AS A RESULT...TEMPS MAY NOT CLIMB AS HIGH BUT WILL STILL BE RELATIVELY PLEASANT IN THE 60S. .LONG TERM...(MONDAY THROUGH FRIDAY) ISSUED AT 1249 PM CDT FRI MAR 20 2015 HIGH CONFIDENCE THROUGH MID WEEK....DECREASING TO LOW CONFIDENCE AFTER THURSDAY. THE MODELS ARE IN GOOD AGREEMENT WITH NEXT SYSTEM TO MOVE THROUGH MID WEEK...BUT AFTER THAT THEY DIVERGE A GREAT DEAL. THEY BOTH KEEP US UNDER A SLOW MOVING UPPER TROUGH BUT DIFFER IN SPOKES OF ENERGY MOVING THROUGH THE TROF AND AVAILABLE MOISTURE. THE GFS CONTINUES TO SHOW NUMEROUS SPOKES OF ENERGY PRODUCING LIGHT RAIN AFTER THE MAIN COLD FRONT PASSAGE IN CONTRAST TO SEVERAL RUNS OF THE ECMWF WHICH KEEPS US DRY AFTER THURSDAY. MAY HAVE SOME SLIGHT CHANCES IN FOR THE POSSIBILITY THE GFS VERIFIES BUT WILL WAIT AND SEE WHAT THE EXTENDED INIT YIELDS AND TAKE IT FROM THERE. I INTRODUCED THUNDER YESTERDAY AND NOW THINK IT WILL BE SURFACE BASED WITH LI`S AT THE SURFACE YIELDING -1 TO -4. ALSO K INDEX 30 AND ABOVE WITH SHOWALTER ZERO TO -4. WILL KEEP TRW- OVER THE ENTIRE AREA THROUGH 00Z THURSDAY AND THEN TAPER IT OFF TO ALONG AND SOUTHEAST OF THE OHIO RIVER 0-06Z THU. PLAN ON TAKING THUNDER COMPLETELY OUT AFTER 06Z THURSDAY. THE THUNDER WILL BE POSSIBLE IN THE WARM SECTOR AFTER THE WARM FRONT HAS LIFTED NORTH AND AHEAD OF THE APPROACHING COLD FRONT FROM THE NORTHWEST. SLIGHTLY ABOVE NORMAL TEMPERATURES FOR MOST OF THE WORK WEEK WILL FALL BELOW NORMAL IN THE COLD FRONTS WAKE AT THE END OF THE WORK WEEK. && .AVIATION... ISSUED AT 411 PM CDT FRI MAR 20 2015 SIGNIFICANT CHANGES MADE TO THE TAFS. DECK OF CLOUDS WITH MVFR BASES WILL MOVE OUT. SATELLITE SHOWS CLEARING IMMINENT AT KCGI AND WILL SOON FOLLOW AT KPAH. SHOULD HAPPEN BY 01-02Z AT KEVV AND KOWB. THE RAP IS NOT DEPICTING THE PLACEMENT CORRECTLY...TOO FAR SOUTH...SO WILL STRICTLY FOLLOW SATELLITE. MODELS DO NOT LINGER THE LOW LEVEL MOISTURE AROUND OVERNIGHT. JUST HIGH CLOUDS AT TIMES. WILL TAKE ANOTHER LOOK AT THE PROSPECT FOR SOME LIGHT FOG GIVEN LIGHT WINDS AND RESIDUAL LOW LEVEL MOISTURE. THE LATEST MOS DOES HINT AT IT FOR LATE TONIGHT...EARLY SATURDAY MORNING. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
310 PM EDT FRI MAR 20 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 310 PM EDT FRI MAR 20 2015 18Z SFC ANALYSIS SHOWS LOW PRESSURE SKIRTING OFF TO THE EAST OF KENTUCKY AS WEAK HIGH PRESSURE IS STARTING TO BUILD INTO THE AREA. THIS HAS ALLOWED THE LIGHT RAIN TO DEPART THE AREA WITH SOME POCKETS OF DRIZZLE STILL POSSIBLE IN THE FAR EAST. UNDER THE LOW CLOUDS SOME PATCHY FOG IS FOUND ON THE RIDGES AND ALSO WHERE THE RAIN HAD ONLY RECENTLY LEFT. TEMPERATURES ARE GENERALLY IN THE MID TO UPPER 40S ACROSS THE AREA WITH A ENCLAVE OF LOWER 50S FOUND IN THE FAR SOUTHEAST. DEWPOINTS...MEANWHILE ARE MOSTLY WITHIN A DEGREE OR TWO OF DRY BULB TEMPS...THOUGH THERE IS A BIT MORE OF A SPREAD TO THE NORTHWEST AS SOME DRIER AIR IS TRYING TO PUSH IN ON WEST TO NORTHWEST WINDS OF 5 TO 10 KTS. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM. THEY ALL DEPICT A WEAK TROUGH CROSSING EASTERN KENTUCKY THIS EVENING WITH A STRONGER ONE MOVING THROUGH THE GREAT LAKES. THE NORTHERN TROUGH STAYS WELL TO THE NORTHEAST WHILE MID LEVEL HEIGHTS STAY NEARLY STATIONARY ON SATURDAY LEAVING THE CWA IN BENIGN NORTHWEST FLOW. MEANWHILE...IN THE SOUTHERN STREAM A BROADER TROUGH WILL SPILL ITS ENERGY THROUGH THE TENNESSEE VALLEY AND DEEP SOUTH INTO SUNDAY MORNING...SLIGHTLY STRONGER IN THE ECMWF AND NAM THAN THE GFS. THIS ALLOWS SOME ENERGY TO BUILD INTO SOUTHERN PARTS OF EAST KENTUCKY SATURDAY NIGHT AND INTO SUNDAY MORNING. GIVEN THE BROAD MODEL AGREEMENT...HAVE FAVORED THE HIGHER RESOLUTION HRRR AND NAM12 FOR WEATHER SPECIFICS THROUGH THE SHORT TERM. SENSIBLE WEATHER WILL FEATURE A CLOUDY AND DAMP NIGHT AS HIGH BOUNDARY LAYER MOISTURE WILL KEEP A THREAT OF MAINLY LIGHT FOG AROUND THROUGH THE DAWN ON SATURDAY. THE EXCEPTION MAY BE IN THE FAR NORTHWEST WHERE THE LOW CLOUDS COULD BREAK UP BEFORE SUNUP. IN ADDITION...THE HIGHER TERRAIN MAY SEE THE LOW CLOUDS SINK DOWN ENOUGH FOR SOME DENSER FOG TO ENSHROUD THE RIDGES. HAVE DEPICTED THIS IN THE GRIDS AND IT WILL BE THE FORECAST CHALLENGE OF THE NIGHT FOR THE EVENING SHIFT. OTHERWISE...THE FOG AND LOW CLOUDS WILL BREAK UP SATURDAY MORNING LEADING TO MOSTLY SUNNY SKIES AND PLEASANT CONDITIONS. SOME HIGH CLOUDS WILL LIKELY IMPACT THE AREA SATURDAY NIGHT AS A COLD FRONT SKIMS BY TO THE NORTH AND A SOUTHERN LOW DEVELOPS WELL TO THE SOUTH. WILL KEEP THE IDEA OF A SMALL RIDGE AND VALLEY TEMPERATURE SPLIT IN THE GRIDS FOR SATURDAY NIGHT...DESPITE THE HIGH CLOUDS. USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO SATURDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD AS WELL AS LINGERING THE LOW CLOUDS/FOG A BIT LONGER THAN MODELS WOULD SUGGEST INTO SATURDAY MORNING. AS FOR POPS...AFTER 00Z TONIGHT KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 225 PM EDT FRI MAR 20 2015 THERE IS GENERAL MODEL AGREEMENT ON THE EVOLUTION OF THE MEAN PATTERN...AS WE MOVE FROM FAIRLY PROGRESSIVE LOW AMPLITUDE FLOW AT THE START OF THE PERIOD TO A HIGHER AMPLITUDE PATTERN TOWARDS THE END OF NEXT WEEK. THE MEAN FLOW WILL TRANSITION...AT LEAST TEMPORARILY...TO THAT PATTERN WHICH HAS BEEN COMMON DURING THE LATE WINTER...WITH A MEAN TROUGH IN THE EASTERN UNITED STATES AND A WESTERN RIDGE. HOWEVER THIS CHANGE WILL NOT FULLY IMPACT OUR LOCAL WEATHER UNTIL LATE NEXT WEEK OR INTO THE FOLLOWING WEEKEND. IN THE MEAN TIME...SPLIT FLOW WILL BE THE RULE FOR LATE IN THE WEEKEND INTO EARLY NEXT WEEK. A SOUTHERN STREAM WAVE WILL SLIDE BY TO OUR SOUTH...MOVING FROM THE LOWER MS VALLEY TO OFF THE SOUTHEAST U.S. COAST EARLY NEXT WEEK. AT THE SAME TIME A WEAK NORTHERN STREAM SYSTEM WILL MOVE ACROSS THE GREAT LAKES. THE MAIN IMPACTS...INCLUDING PRECIPITATION CHANCES WILL REMAIN TO OUR SOUTH AND NORTH WITH EACH RESPECTIVE SYSTEM. AFTER THESE PASS BY...A STRONGER SYSTEM EMERGING FROM THE PLAINS...WILL FIRST BRING A SURGE OF WARM AIR INTO OUR REGION FOR THE MIDDLE OF NEXT WEEK...WITH A COLD FRONT THEN FOLLOWING AS SURFACE LOW PRESSURE MOVES ACROSS THE GREAT LAKES. THE TIMING OF THE COLDER AIR AND BEST PRECIPITATION CHANCES FOR THE SECOND HALF OF NEXT WEEK REMAIN IN QUESTION AT THIS TIME...WITH DETAILS VARYING FROM MODEL TO MODEL AND RUN TO RUN. HOWEVER IT DOES APPEAR A SIGNIFICANT SHOT OF COLDER AIR WILL AFFECT THE REGION AT THE END OR JUST BEYOND THE END OF THIS FORECAST PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 230 PM EDT FRI MAR 20 2015 LIGHT RAIN IS EXITING THE AREA BUT LOW CLOUDS AND FOG WILL KEEP IFR AND MVFR CONDITIONS GOING ACROSS EASTERN KENTUCKY THROUGH THE EVENING. EXPECT THE FOG THE LOW CLOUDS TO HOLD IN FOR MUCH OF THE NIGHT...AS WELL...WITH CIGS EVEN LOWERING A BIT LATE IN THE EVENING AND DURING THE OVERNIGHT PERIOD. CLOUDS THEN LOOK TO SCATTER OUT EARLY SATURDAY MORNING FROM NORTHWEST TO SOUTHEAST... AFTER DAWN...FOR VFR CONDITIONS THAT WILL STICK AROUND THROUGH THE DAY. WINDS WILL GENERALLY BE AROUND 5 KTS OR LESS THROUGH THE PERIOD OUT OF THE WEST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GREIF LONG TERM...SBH AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
229 PM EDT FRI MAR 20 2015 .UPDATE... ISSUED AT 210 PM EDT FRI MAR 20 2015 DID A QUICK UPDATE EARLIER TO FINE TUNE THE POPS AND WX AS THE LIGHT RAIN EXITS. ALSO...TWEAKED THE FOG INTO THE EVENING FOR MAINLY THE HIGHER TERRAIN. FINALLY...TOUCHED UP THE T AND TD GRIDS INTO THE EVENING PER THE LATEST OBS AND TRENDS. THESE UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 1055 AM EDT FRI MAR 20 2015 14Z SFC ANALYSIS SHOWS AN AREA OF LOW PRESSURE MOVING OUT OF EASTERN KENTUCKY. THIS WILL EVENTUALLY TAKE THE TRAILING LIGHT RAIN WITH IT...THOUGH A FEW POCKETS WILL REMAIN INTO THE AFTERNOON ALONG WITH CLOUDY SKIES. IN ADDITION TO THE RAIN...THERE IS SOME PATCHY FOG OUT THERE...MAINLY OVER THE HIGHER TERRAIN. TEMPERATURES ARE GENERALLY IN THE 45 TO 50 DEGREE RANGE WITH DEWPOINTS JUST A DEGREE OR TWO LESS. WINDS ARE MOSTLY LIGHT THROUGH EAST KENTUCKY BECOMING WESTERLY AT 5 TO 10 KTS AS THE LOW DEPARTS. HAVE UPDATED THE GRIDS TO REFLECT THE LAST OF THE RAIN PER THE LATEST RADAR TRENDS AND HRRR GUIDANCE. ALSO FINE TUNED THE T AND TD GRIDS THROUGH THE AFTERNOON BASED ON THE LATEST SHORTBLEND GUIDANCE AND OBS/TRENDS. THE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS ALONG WITH A FRESHENED SET OF ZONES AND HWO. UPDATE ISSUED AT 800 AM EDT FRI MAR 20 2015 LIGHT RAIN HAS FILLED BACK IN ACROSS PORTIONS OF THE AREA OVER THE PAST COUPLE OF HOURS. THE FIRST BAND OF BETTER RETURNS WILL EXIT FAR NORTHEASTERN KENTUCKY IN THE NEXT 30 MINUTES TO AN HOUR. ANOTHER MORE SUSTAINED BAND OF PRECIPITATION IS COMING IN FROM WESTERN KENTUCKY. THE LATEST HRRR CONTINUES TO SHOW THIS BAND HOLDING TOGETHER WELL AS IT ENTERS OUR SOUTHWESTERN COUNTIES BETWEEN 9 AND 10 AM. FRESHENED UP THE POPS...TEMPERATURES...AND DEW POINTS TO BETTER CAPTURE THE LATEST TRENDS IN THE OBSERVATIONS. OTHERWISE...THE FORECAST REMAINS ON TRACK. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 353 AM EDT FRI MAR 20 2015 WEAK SURFACE LOW PRESSURE IS CURRENTLY RESIDING ACROSS NORTHEASTERN KENTUCKY...WITH HIGH PRESSURE SETTLING IN ACROSS THE SOUTHERN PLAINS STATES. ALOFT...A NORTHERN STREAM SHORT WAVE TROUGH IS DROPPING SOUTHEAST INTO THE GREAT LAKES AND CENTRAL PLAINS. PRECIPITATION HAS DWINDLED ACROSS EASTERN KENTUCKY DURING THE OVERNIGHT HOURS...WITH A LITTLE PATCHY DRIZZLE AND FOG LEFT IN ITS WAKE. TEMPERATURES HAVE CREPT UP A LITTLE DURING THE OVERNIGHT HOURS...RANGING FROM THE LOW 40S NORTH OF I-64...TO THE MID AND UPPER 40S SOUTH OF THE HAL ROGERS AND HIGHWAY 80 CORRIDORS. THE NORTHERN STREAM SHORT WAVE TROUGH WILL CONTINUE TO MOVE SOUTHEAST TOWARDS OUR AREA THROUGH TODAY...HELPING TO REINFORCE THE WEAK SURFACE FRONT CURRENTLY ALIGNED ACROSS THE COMMONWEALTH. EXPECT A RESURGENCE IN THE LIGHT RAIN THROUGH THE MORNING...BEFORE THE FORCING AND MOISTURE SHIFT OFF TO THE SOUTHEAST DURING THE AFTERNOON. HIGH PRESSURE WILL BUILD IN TONIGHT...BEFORE GETTING TEMPORARILY BUCKLED BY A COLD FRONT THAT WILL SWING THROUGH THE OHIO VALLEY ON SATURDAY. MOISTURE WILL BE LACKING WITH THIS FRONT...SO DRY WEATHER WILL CONTINUE TO HOLD ON. WILL STAY ON THE COOLER SIDE OF GUIDANCE TODAY...WITH CLOUDS LINGERING. HIGHS WILL TOP OUT IN THE LOW TO MID 50S...WITH LOWS TONIGHT DOWN AROUND 40 ACCOMPANIED BY SOME PATCHY FOG. SOUTHWEST WINDS OUT AHEAD OF THE APPROACHING FRONT WILL ALLOW FOR HIGHS ON SATURDAY TO RETURN TO THE 60S. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 225 PM EDT FRI MAR 20 2015 THERE IS GENERAL MODEL AGREEMENT ON THE EVOLUTION OF THE MEAN PATTERN...AS WE MOVE FROM FAIRLY PROGRESSIVE LOW AMPLITUDE FLOW AT THE START OF THE PERIOD TO A HIGHER AMPLITUDE PATTERN TOWARDS THE END OF NEXT WEEK. THE MEAN FLOW WILL TRANSITION...AT LEAST TEMPORARILY...TO THAT PATTERN WHICH HAS BEEN COMMON DURING THE LATE WINTER...WITH A MEAN TROUGH IN THE EASTERN UNITED STATES AND A WESTERN RIDGE. HOWEVER THIS CHANGE WILL NOT FULLY IMPACT OUR LOCAL WEATHER UNTIL LATE NEXT WEEK OR INTO THE FOLLOWING WEEKEND. IN THE MEAN TIME...SPLIT FLOW WILL BE THE RULE FOR LATE IN THE WEEKEND INTO EARLY NEXT WEEK. A SOUTHERN STREAM WAVE WILL SLIDE BY TO OUR SOUTH...MOVING FROM THE LOWER MS VALLEY TO OFF THE SOUTHEAST U.S. COAST EARLY NEXT WEEK. AT THE SAME TIME A WEAK NORTHERN STREAM SYSTEM WILL MOVE ACROSS THE GREAT LAKES. THE MAIN IMPACTS...INCLUDING PRECIPITATION CHANCES WILL REMAIN TO OUR SOUTH AND NORTH WITH EACH RESPECTIVE SYSTEM. AFTER THESE PASS BY...A STRONGER SYSTEM EMERGING FROM THE PLAINS...WILL FIRST BRING A SURGE OF WARM AIR INTO OUR REGION FOR THE MIDDLE OF NEXT WEEK...WITH A COLD FRONT THEN FOLLOWING AS SURFACE LOW PRESSURE MOVES ACROSS THE GREAT LAKES. THE TIMING OF THE COLDER AIR AND BEST PRECIPITATION CHANCES FOR THE SECOND HALF OF NEXT WEEK REMAIN IN QUESTION AT THIS TIME...WITH DETAILS VARYING FROM MODEL TO MODEL AND RUN TO RUN. HOWEVER IT DOES APPEAR A SIGNIFICANT SHOT OF COLDER AIR WILL AFFECT THE REGION AT THE END OR JUST BEYOND THE END OF THIS FORECAST PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 230 PM EDT FRI MAR 20 2015 LIGHT RAIN IS EXITING THE AREA BUT LOW CLOUDS AND FOG WILL KEEP IFR AND MVFR CONDITIONS GOING ACROSS EASTERN KENTUCKY THROUGH THE EVENING. EXPECT THE FOG THE LOW CLOUDS TO HOLD IN FOR MUCH OF THE NIGHT...AS WELL...WITH CIGS EVEN LOWERING A BIT LATE IN THE EVENING AND DURING THE OVERNIGHT PERIOD. CLOUDS THEN LOOK TO SCATTER OUT EARLY SATURDAY MORNING FROM NORTHWEST TO SOUTHEAST... AFTER DAWN...FOR VFR CONDITIONS THAT WILL STICK AROUND THROUGH THE DAY. WINDS WILL GENERALLY BE AROUND 5 KTS OR LESS THROUGH THE PERIOD OUT OF THE WEST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...GEOGERIAN LONG TERM...SBH AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1055 AM EDT FRI MAR 20 2015 .UPDATE... ISSUED AT 1055 AM EDT FRI MAR 20 2015 14Z SFC ANALYSIS SHOWS AN AREA OF LOW PRESSURE MOVING OUT OF EASTERN KENTUCKY. THIS WILL EVENTUALLY TAKE THE TRAILING LIGHT RAIN WITH IT...THOUGH A FEW POCKETS WILL REMAIN INTO THE AFTERNOON ALONG WITH CLOUDY SKIES. IN ADDITION TO THE RAIN...THERE IS SOME PATCHY FOG OUT THERE...MAINLY OVER THE HIGHER TERRAIN. TEMPERATURES ARE GENERALLY IN THE 45 TO 50 DEGREE RANGE WITH DEWPOINTS JUST A DEGREE OR TWO LESS. WINDS ARE MOSTLY LIGHT THROUGH EAST KENTUCKY BECOMING WESTERLY AT 5 TO 10 KTS AS THE LOW DEPARTS. HAVE UPDATED THE GRIDS TO REFLECT THE LAST OF THE RAIN PER THE LATEST RADAR TRENDS AND HRRR GUIDANCE. ALSO FINE TUNED THE T AND TD GRIDS THROUGH THE AFTERNOON BASED ON THE LATEST SHORTBLEND GUIDANCE AND OBS/TRENDS. THE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS ALONG WITH A FRESHENED SET OF ZONES AND HWO. UPDATE ISSUED AT 800 AM EDT FRI MAR 20 2015 LIGHT RAIN HAS FILLED BACK IN ACROSS PORTIONS OF THE AREA OVER THE PAST COUPLE OF HOURS. THE FIRST BAND OF BETTER RETURNS WILL EXIT FAR NORTHEASTERN KENTUCKY IN THE NEXT 30 MINUTES TO AN HOUR. ANOTHER MORE SUSTAINED BAND OF PRECIPITATION IS COMING IN FROM WESTERN KENTUCKY. THE LATEST HRRR CONTINUES TO SHOW THIS BAND HOLDING TOGETHER WELL AS IT ENTERS OUR SOUTHWESTERN COUNTIES BETWEEN 9 AND 10 AM. FRESHENED UP THE POPS...TEMPERATURES...AND DEW POINTS TO BETTER CAPTURE THE LATEST TRENDS IN THE OBSERVATIONS. OTHERWISE...THE FORECAST REMAINS ON TRACK. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 353 AM EDT FRI MAR 20 2015 WEAK SURFACE LOW PRESSURE IS CURRENTLY RESIDING ACROSS NORTHEASTERN KENTUCKY...WITH HIGH PRESSURE SETTLING IN ACROSS THE SOUTHERN PLAINS STATES. ALOFT...A NORTHERN STREAM SHORT WAVE TROUGH IS DROPPING SOUTHEAST INTO THE GREAT LAKES AND CENTRAL PLAINS. PRECIPITATION HAS DWINDLED ACROSS EASTERN KENTUCKY DURING THE OVERNIGHT HOURS...WITH A LITTLE PATCHY DRIZZLE AND FOG LEFT IN ITS WAKE. TEMPERATURES HAVE CREPT UP A LITTLE DURING THE OVERNIGHT HOURS...RANGING FROM THE LOW 40S NORTH OF I-64...TO THE MID AND UPPER 40S SOUTH OF THE HAL ROGERS AND HIGHWAY 80 CORRIDORS. THE NORTHERN STREAM SHORT WAVE TROUGH WILL CONTINUE TO MOVE SOUTHEAST TOWARDS OUR AREA THROUGH TODAY...HELPING TO REINFORCE THE WEAK SURFACE FRONT CURRENTLY ALIGNED ACROSS THE COMMONWEALTH. EXPECT A RESURGENCE IN THE LIGHT RAIN THROUGH THE MORNING...BEFORE THE FORCING AND MOISTURE SHIFT OFF TO THE SOUTHEAST DURING THE AFTERNOON. HIGH PRESSURE WILL BUILD IN TONIGHT...BEFORE GETTING TEMPORARILY BUCKLED BY A COLD FRONT THAT WILL SWING THROUGH THE OHIO VALLEY ON SATURDAY. MOISTURE WILL BE LACKING WITH THIS FRONT...SO DRY WEATHER WILL CONTINUE TO HOLD ON. WILL STAY ON THE COOLER SIDE OF GUIDANCE TODAY...WITH CLOUDS LINGERING. HIGHS WILL TOP OUT IN THE LOW TO MID 50S...WITH LOWS TONIGHT DOWN AROUND 40 ACCOMPANIED BY SOME PATCHY FOG. SOUTHWEST WINDS OUT AHEAD OF THE APPROACHING FRONT WILL ALLOW FOR HIGHS ON SATURDAY TO RETURN TO THE 60S. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 407 AM EDT FRI MAR 20 2015 PERIOD BEGINS QUIET ACROSS EASTERN KENTUCKY UNDER MORE OF NW FLOW ALOFT. WE BEGIN WATCHING A SOUTHERN STREAM WAVE ACROSS TX MOVE EAST AS WE MOVE INTO THE FIRST PART OF THE WORK WEEK. WE WILL BE SANDWICHED BETWEEN THE NORTHERN STREAM AND SOUTHERN STREAM SYSTEMS. MOST GUIDANCE KEEP THE SOUTHERN STREAM SYSTEM SOUTH OF EASTERN KENTUCKY...SO HAVE KEPT POPS SOUTH OF THE REGION AS WE BEGIN THE WORK WEEK MONDAY. THE ECMWF DOES BRING A SHORTWAVE ALONG THE NORTHERN STREAM AS WE MOVE INTO MONDAY AFTERNOON SO DO HAVE A SLIGHT POP ACROSS THE FAR NORTH...HOWEVER CONFIDENCE REMAINS LOW WITH THIS AS ECMWF IS THE ONLY GUIDANCE INDICATING THIS AT THIS POINT. A WEAK WARM FRONT ADVANCES NORTHEAST...AS WE MOVE INTO LATE TUESDAY INTO TUESDAY NIGHT AHEAD OF STRENGTHENING SURFACE LOW MOVING OUT OF THE NORTHERN PLAINS INTO THE GREAT LAKES. THEN GUIDANCE BECOMES A BIT MORE DIVERGENT AS WE MOVE WEDNESDAY INTO THURSDAY. THE ECMWF IS A BIT QUICKER WITH MOVING THE COLD FRONT ACROSS THE REGION AND MOST OF THE PRECIP EAST BY THURSDAY. WHILE THE GFS SLOWS THE PROGRESSION OF THE FRONT AND EVENTUALLY DEVELOPS A SECONDARY LOW ALONG THE FRONT. GIVEN UNCERTAINTY DID STICK CLOSE TO THE MODEL BLEND POPS AT THIS POINT. DID KEEP LIKELY POPS IN SPOTS GIVEN THAT IT DOES SEEM WE WILL SEE MEASURABLE PRECIPITATION ASSOCIATED WITH THIS DISTURBANCE. THERE IS SOME ELEVATED INSTABILITY SHOWING UP IN THE FORECAST SOUNDINGS AS WE MOVE INTO THE AFTERNOON ON WEDNESDAY AND THURSDAY. HOWEVER HAVE NO MENTION OF THUNDER AT THIS POINT...GIVEN THAT THIS WILL BE HIGHLY DEPENDENT ON THE EVOLUTION OF THIS SYSTEM WHICH REMAINS UNCERTAIN. OTHERWISE HIGH TEMPS THROUGH THE PERIOD WILL GENERALLY BE IN THE 50S AND 60S WITH PERHAPS WARMER TEMPS ON WEDNESDAY WHERE HIGHS COULD NEAR THE 70S. LOW TEMPS THROUGH THE PERIOD WILL GENERALLY BE IN THE 30S AND 40S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 800 AM EDT FRI MAR 20 2015 LIGHT RAIN AND FOG WILL KEEP MAINLY IFR OR LOWER CONDITIONS ACROSS EASTERN KENTUCKY THROUGH THE MORNING HOURS. THE LIGHT PRECIPITATION WILL THEN DIMINISH THIS AFTERNOON FROM NORTHWEST TO SOUTHEAST. CEILINGS WILL GRADUALLY IMPROVE TO MVFR STATUS BY LATE IN THE DAY OR EARLY EVENING HOURS. CLOUDS THEN LOOK TO SCATTER OUT OVERNIGHT FROM NORTHWEST TO SOUTHEAST. WINDS WILL GENERALLY BE AROUND 5 KTS OR LESS THROUGH THE PERIOD...BEGINNING OUT OF THE SOUTHWEST AND THEN GRADUALLY VEERING TO THE WEST THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...GEOGERIAN LONG TERM...DJ AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
800 AM EDT FRI MAR 20 2015 .UPDATE... ISSUED AT 800 AM EDT FRI MAR 20 2015 LIGHT RAIN HAS FILLED BACK IN ACROSS PORTIONS OF THE AREA OVER THE PAST COUPLE OF HOURS. THE FIRST BAND OF BETTER RETURNS WILL EXIT FAR NORTHEASTERN KENTUCKY IN THE NEXT 30 MINUTES TO AN HOUR. ANOTHER MORE SUSTAINED BAND OF PRECIPITATION IS COMING IN FROM WESTERN KENTUCKY. THE LATEST HRRR CONTINUES TO SHOW THIS BAND HOLDING TOGETHER WELL AS IT ENTERS OUR SOUTHWESTERN COUNTIES BETWEEN 9 AND 10 AM. FRESHENED UP THE POPS...TEMPERATURES...AND DEW POINTS TO BETTER CAPTURE THE LATEST TRENDS IN THE OBSERVATIONS. OTHERWISE...THE FORECAST REMAINS ON TRACK. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 353 AM EDT FRI MAR 20 2015 WEAK SURFACE LOW PRESSURE IS CURRENTLY RESIDING ACROSS NORTHEASTERN KENTUCKY...WITH HIGH PRESSURE SETTLING IN ACROSS THE SOUTHERN PLAINS STATES. ALOFT...A NORTHERN STREAM SHORT WAVE TROUGH IS DROPPING SOUTHEAST INTO THE GREAT LAKES AND CENTRAL PLAINS. PRECIPITATION HAS DWINDLED ACROSS EASTERN KENTUCKY DURING THE OVERNIGHT HOURS...WITH A LITTLE PATCHY DRIZZLE AND FOG LEFT IN ITS WAKE. TEMPERATURES HAVE CREPT UP A LITTLE DURING THE OVERNIGHT HOURS...RANGING FROM THE LOW 40S NORTH OF I-64...TO THE MID AND UPPER 40S SOUTH OF THE HAL ROGERS AND HIGHWAY 80 CORRIDORS. THE NORTHERN STREAM SHORT WAVE TROUGH WILL CONTINUE TO MOVE SOUTHEAST TOWARDS OUR AREA THROUGH TODAY...HELPING TO REINFORCE THE WEAK SURFACE FRONT CURRENTLY ALIGNED ACROSS THE COMMONWEALTH. EXPECT A RESURGENCE IN THE LIGHT RAIN THROUGH THE MORNING...BEFORE THE FORCING AND MOISTURE SHIFT OFF TO THE SOUTHEAST DURING THE AFTERNOON. HIGH PRESSURE WILL BUILD IN TONIGHT...BEFORE GETTING TEMPORARILY BUCKLED BY A COLD FRONT THAT WILL SWING THROUGH THE OHIO VALLEY ON SATURDAY. MOISTURE WILL BE LACKING WITH THIS FRONT...SO DRY WEATHER WILL CONTINUE TO HOLD ON. WILL STAY ON THE COOLER SIDE OF GUIDANCE TODAY...WITH CLOUDS LINGERING. HIGHS WILL TOP OUT IN THE LOW TO MID 50S...WITH LOWS TONIGHT DOWN AROUND 40 ACCOMPANIED BY SOME PATCHY FOG. SOUTHWEST WINDS OUT AHEAD OF THE APPROACHING FRONT WILL ALLOW FOR HIGHS ON SATURDAY TO RETURN TO THE 60S. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 407 AM EDT FRI MAR 20 2015 PERIOD BEGINS QUIET ACROSS EASTERN KENTUCKY UNDER MORE OF NW FLOW ALOFT. WE BEGIN WATCHING A SOUTHERN STREAM WAVE ACROSS TX MOVE EAST AS WE MOVE INTO THE FIRST PART OF THE WORK WEEK. WE WILL BE SANDWICHED BETWEEN THE NORTHERN STREAM AND SOUTHERN STREAM SYSTEMS. MOST GUIDANCE KEEP THE SOUTHERN STREAM SYSTEM SOUTH OF EASTERN KENTUCKY...SO HAVE KEPT POPS SOUTH OF THE REGION AS WE BEGIN THE WORK WEEK MONDAY. THE ECMWF DOES BRING A SHORTWAVE ALONG THE NORTHERN STREAM AS WE MOVE INTO MONDAY AFTERNOON SO DO HAVE A SLIGHT POP ACROSS THE FAR NORTH...HOWEVER CONFIDENCE REMAINS LOW WITH THIS AS ECMWF IS THE ONLY GUIDANCE INDICATING THIS AT THIS POINT. A WEAK WARM FRONT ADVANCES NORTHEAST...AS WE MOVE INTO LATE TUESDAY INTO TUESDAY NIGHT AHEAD OF STRENGTHENING SURFACE LOW MOVING OUT OF THE NORTHERN PLAINS INTO THE GREAT LAKES. THEN GUIDANCE BECOMES A BIT MORE DIVERGENT AS WE MOVE WEDNESDAY INTO THURSDAY. THE ECMWF IS A BIT QUICKER WITH MOVING THE COLD FRONT ACROSS THE REGION AND MOST OF THE PRECIP EAST BY THURSDAY. WHILE THE GFS SLOWS THE PROGRESSION OF THE FRONT AND EVENTUALLY DEVELOPS A SECONDARY LOW ALONG THE FRONT. GIVEN UNCERTAINTY DID STICK CLOSE TO THE MODEL BLEND POPS AT THIS POINT. DID KEEP LIKELY POPS IN SPOTS GIVEN THAT IT DOES SEEM WE WILL SEE MEASURABLE PRECIPITATION ASSOCIATED WITH THIS DISTURBANCE. THERE IS SOME ELEVATED INSTABILITY SHOWING UP IN THE FORECAST SOUNDINGS AS WE MOVE INTO THE AFTERNOON ON WEDNESDAY AND THURSDAY. HOWEVER HAVE NO MENTION OF THUNDER AT THIS POINT...GIVEN THAT THIS WILL BE HIGHLY DEPENDENT ON THE EVOLUTION OF THIS SYSTEM WHICH REMAINS UNCERTAIN. OTHERWISE HIGH TEMPS THROUGH THE PERIOD WILL GENERALLY BE IN THE 50S AND 60S WITH PERHAPS WARMER TEMPS ON WEDNESDAY WHERE HIGHS COULD NEAR THE 70S. LOW TEMPS THROUGH THE PERIOD WILL GENERALLY BE IN THE 30S AND 40S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 800 AM EDT FRI MAR 20 2015 LIGHT RAIN AND FOG WILL KEEP MAINLY IFR OR LOWER CONDITIONS ACROSS EASTERN KENTUCKY THROUGH THE MORNING HOURS. THE LIGHT PRECIPITATION WILL THEN DIMINISH THIS AFTERNOON FROM NORTHWEST TO SOUTHEAST. CEILINGS WILL GRADUALLY IMPROVE TO MVFR STATUS BY LATE IN THE DAY OR EARLY EVENING HOURS. CLOUDS THEN LOOK TO SCATTER OUT OVERNIGHT FROM NORTHWEST TO SOUTHEAST. WINDS WILL GENERALLY BE AROUND 5 KTS OR LESS THROUGH THE PERIOD...BEGINNING OUT OF THE SOUTHWEST AND THEN GRADUALLY VEERING TO THE WEST THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEOGERIAN SHORT TERM...GEOGERIAN LONG TERM...DJ AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1033 PM EDT SAT MAR 21 2015 .SYNOPSIS... LOW PRESSURE WILL INTENSIFY ACROSS THE MARITIMES OVERNIGHT THROUGH SUNDAY. HIGH PRESSURE WILL BUILD EAST TOWARD THE REGION LATER MONDAY. && .NEAR TERM /THROUGH SUNDAY/... 1020 PM UPDATE: SNOW CONTINUES TO FILL IN ACROSS THE REGION W/THE LATEST RADAR LOOPS SHOWING SOME ENHANCED BANDS MOVING N THROUGH THE MT. KATAHDIN AND PATTEN REGION. THE LATEST RUN OF THE NAM12 AND HRRR 3KM MODELS SHOWING THIS AREA WELL AND HAVE IT EXPANDING INTO NNE MAINE LATER TONIGHT. THE BACK EDGE OF THE SNOW LOOKS LIKE IT WILL CLEAR THE SW AND DOWNEAST AREA AFTER 06Z AS ENERGY SHIFTS TO THE LOW MOVING INTO THE CANADIAN MARITIMES. SNOW IS EXPECTED TO CONTINUE ACROSS THE NORTHERN TIER ON SUNDAY W/THE WRAP-AROUND MOISTURE BEING PULLED BACK IN FROM THE NORTH. THE HIGHEST SNOWFALL IS EXPECTED ACROSS NW AND NE AREAS W/2-4 INCHES AND 2 INCHES OR LESS ELSEWHERE. TEMPERATURES HAVE BEEN SLOW TO FALL BACK AND ADJUSTMENTS WERE DONE TO THE HRLY TEMPERATURES TO BRING THEM UP AS WELL AS THE OVERNIGHT MINS. CURRENT WINTER WEATHER ADVISORY AND WIND ADVISORY REMAINS IN EFFECT. LOW PRESSURE MOVING EAST ACROSS THE REGION AND ANOTHER LOW TRACKING TOWARD NOVA SCOTIA WILL MERGE AND RAPIDLY INTENSIFY ACROSS NOVA SCOTIA TONIGHT. THE STRONG LOW WILL THEN LIFT NORTH ACROSS THE GULF OF SAINT LAWRENCE SUNDAY WHILE UPPER LEVEL LOW PRESSURE CROSSES THE REGION. SNOW WILL OCCUR ACROSS THE REGION TONIGHT...WITH THE GREATER ACCUMULATIONS ACROSS NORTHERN AREAS AND LESSER ACCUMULATIONS DOWNEAST. GENERALLY EXPECT OVERNIGHT SNOW ACCUMULATIONS OF 2 TO 4 INCHES ACROSS NORTHERN AREAS TONIGHT TAPERING TO AROUND AN INCH DOWNEAST. MOISTURE WRAPPING AROUND THE UPPER LOW WILL KEEP MOSTLY CLOUDY SKIES ALONG A CHANCE OF SNOW SHOWERS ACROSS THE NORTH AND MOUNTAINS SUNDAY...WITH ADDITIONAL SNOW ACCUMULATIONS OF AROUND AN INCH POSSIBLE. PARTLY/MOSTLY SUNNY SKIES ARE EXPECTED DOWNEAST SUNDAY. WINDS WILL ALSO INCREASE RAPIDLY LATE TONIGHT WITH THE TIGHTENING PRESSURE GRADIENT BETWEEN THE INTENSIFYING MARITIMES LOW AND HIGH PRESSURE TO THE WEST. FORECAST SOUNDINGS SHOW A DEEP MIXED LAYER ACROSS THE REGION SUNDAY WHICH WILL HELP TRANSPORT THE STRONG WINDS ALOFT TO THE SURFACE. THE TIGHT PRESSURE GRADIENT...COLD ADVECTION AND DEEP LAYER MIXING WILL SUPPORT SUSTAINED WINDS OF 20 TO 30 MPH...WITH GUSTS UP TO 50 MPH...ACROSS THE REGION SUNDAY. HAVE ISSUED A WINTER WEATHER ADVISORY ACROSS NORTHERN AREAS TONIGHT THROUGH SUNDAY. THIS WILL COVER THE SNOW TONIGHT THEN THE BLOWING SNOW AND STRONG WINDS SUNDAY. HAVE ISSUED A WIND ADVISORY ACROSS THE REMAINDER OF THE FORECAST AREA SUNDAY WHERE LESSER SNOW ACCUMULATIONS WILL OCCUR TONIGHT THOUGH WIND GUSTS OF UP TO 50 MPH WILL ALSO OCCUR SUNDAY. LOW TEMPERATURES TONIGHT WILL RANGE FROM AROUND 5 TO 10 ABOVE NORTH...TO THE MID TEENS DOWNEAST. HIGH TEMPERATURES SUNDAY WILL RANGE FROM 10 TO 15 NORTH...TO THE UPPER TEENS TO AROUND 20 DOWNEAST. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... MAINLY DRY AND CHILLY CONDITIONS ARE EXPECTED DURING THE SHORT TERM AS A HIGH PRESSURE SYSTEM FROM CANADA MOVES OVER THE NORTHEAST AND CANADIAN MARITIMES. BUT SOME LINGERING SNOW SHOWERS ARE POSSIBLE ACROSS NRN MAINE SUNDAY NIGHT AND MONDAY MORNING. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... MAINLY DRY CONDITIONS AND ABOVE NORMAL TEMPERATURES WILL RETURN TO THE FCST AREA DURING THE BEGINNING OF THE EXTENDED FORECAST PERIOD AS A RIDGE OF HIGH PRESSURE BUILDS OVER EAST COAST. HIGHS ON WEDNESDAY WILL RANGE FROM THE MID 30S NORTH TO THE LOWER 40S SOUTH. TEMPERATURES ARE EXPECTED TO BE EVEN WARMER ON THURSDAY WITH HIGHS INTO THE 40S FOR MOST AREAS. HOWEVER PRECIPITATION WILL ACCOMPANY THE WARMER AIR AS A WARM FRONT PROPAGATES NEWD ACROSS NEW ENGLAND. PRECIP TYPE WILL INITIALLY BE SNOW/SLEET BUT THEN TRANSITION TO FREEZING RAIN AND JUST RAIN BY THURSDAY AFTERNOON. THE COLD AIR WILL RETURN THURSDAY NIGHT AFTER A COLD FRONT MOVES THROUGH...CAUSING MOST OF THE RAIN TO MIX WITH AND CHANGE OVER TO SNOW BY EARLY FRIDAY MORNING. AN UPPER LEVEL TROUGH MOVING ACROSS THE NORTHEAST WILL PRODUCE SCTD SNOW SHOWERS ACROSS MUCH OF MAINE FRIDAY INTO SATURDAY...ESPECIALLY DURING THE DAYTIME HOURS WHEN THERE WILL BE SOME INSTABILITY. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... NEAR TERM: MVFR TO LIFR CONDITIONS ARE EXPECTED ACROSS NORTHERN AREAS TONIGHT. ACROSS DOWNEAST AREAS...EXPECT MVFR TO IFR CONDITIONS EARLY TONIGHT IMPROVING TO VFR OVERNIGHT. OCCASIONAL MVFR CONDITIONS WILL OCCUR ACROSS THE NORTH AND MOUNTAINS SUNDAY WITH VFR CONDITIONS DOWNEAST. STRONG GUSTY WINDS WILL OCCUR ACROSS THE ENTIRE REGION LATER TONIGHT THROUGH SUNDAY WITH SUSTAINED WINDS OF 20 TO 30 MPH AND GUSTS UP T0 50 MPH. SHORT TERM: IFR TO MVFR CONDITIONS ARE EXPECTED ACROSS NRN MAINE SUNDAY NIGHT IN ASSOCIATION WITH SNOW SHOWERS AFFECTING THIS AREA. CONDITIONS WILL ONLY IMPROVE SLIGHTLY ON MONDAY. VFR CONDITIONS SHOULD RETURN BY TUESDAY. WINDS WILL BE STRONG AND GUSTY SUNDAY NIGHT INTO MONDAY...THEN DIMINISH MONDAY NIGHT INTO TUESDAY. VFR CONDITIONS ARE EXPECTED EARLY WEDNESDAY...WITH IFR/LIFR CONDITIONS LATER WEDNESDAY INTO THURSDAY. && .MARINE... NEAR TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY LEVELS EARLY TONIGHT. GALE CONDITIONS WILL THEN DEVELOP LATER TONIGHT AND PERSIST SUNDAY. MODERATE FREEZING SPRAY WILL OCCUR SUNDAY. A GALE WARNING IS IN EFFECT STARTING LATE TONIGHT AND RUNNING THROUGH SUNDAY. A FREEZING SPRAY ADVISORY IS IN EFFECT FOR SUNDAY. VISIBILITIES COULD BE REDUCED IN RAIN/SNOW TONIGHT. SHORT TERM: A GALE WARNING AND FREEZING SPRAY ADVISORY WILL BE IN EFFECT FOR THE COASTAL ZONES SUNDAY NIGHT DUE TO STRONG NW WINDS ACROSS THE GULF OF MAINE. WINDS SHOULD DIMINISH SLIGHTLY ON MONDAY WHEN THE WARNING COULD PROBABLY BE REDUCED TO A SCY. THE FREEZING SPRAY SHOULD ALSO DECREASE IN INTENSITY AND COVERAGE ON MONDAY AS WELL. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY UNTIL 8 PM EDT SUNDAY FOR MEZ001>006- 010. WIND ADVISORY FROM 8 AM TO 8 PM EDT SUNDAY FOR MEZ011-015>017- 029>032. MARINE...FREEZING SPRAY ADVISORY FROM 6 AM SUNDAY TO 8 AM EDT MONDAY FOR ANZ050>052. GALE WARNING FROM 5 AM SUNDAY TO 8 AM EDT MONDAY FOR ANZ050>052. && $$ NEAR TERM...HEWITT
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1240 PM CDT FRI MAR 20 2015 .UPDATE...LATEST SATELLITE IMAGERY SHOWED THE REGION UNDER ZONAL FLOW WITH A WEAK UPPER DISTURBANCE EXITING THE REGION WHILE A CLOSED MID TO UPPER LEVEL LOW WAS OBSERVED OVER BAJA. A STATIONARY FRONTAL BOUNDARY WAS NOTED ACROSS THE INTERSTATE 20 CORRIDOR ALONG WITH AN INVERTED TROUGH EXTENDING NORTH. AREA RADARS WERE PICKING UP SHOWERS EXITING THE NORTHEAST PORTION OF THE ARKLAMISS AS THE 16Z HRRR WAS SHOWING. SO HAVE ADJUSTED POPS ACCORDINGLY. LEFT ISOLATED POPS FOR THE REST OF THE AFTERNOON. HOURLY TEMPS SEEM TO BE PROCEEDING AS FORECAST. SO WILL STICK WITH HIGHS FROM THE MIDDLE 60S NORTHWEST TO THE LOWER 80S SOUTHEAST./17/ && .AVIATION...AREAS OF MODERATE TO HEAVY RAIN IMPACTING KGLH...KGWO AND HEADED FOR KGTR LATER THIS MORNING. BOTH VSBY AND CIGS HAVE BEEN REDUCED TO IFR AT TIMES. FOR TAF SITES FURTHER SOUTH...THERE HAVE BEEN INTERMITTENT CIG AND VSBY RESTRICTIONS BUT THERE SHOULD BE AN IMPROVEMENT THROUGH THE LATE MORNING AND AFTERNOON HOURS AS VISIBLE SATELLITE IMAGERY SHOWS AREAS OF SUN SOUTH OF INTERSTATE 20. /SW/ && /.PREVIOUS DISCUSSION 452 AM CDT FRI MAR 20 2015 .SHORT TERM...TODAY THROUGH SATURDAY NIGHT...WATER VAPOR IMAGERY/RAP ANALYSIS SHOWS THE CIRCULATION AROUND A CLOSED LOW SPINNING OVER THE BAJA REGION AND A NORTHERN STREAM SHORTWAVE DROPPING ACROSS THE MID MISSISSIPPI VALLEY. OUR CWA WILL REMAIN DOWNSTREAM OF THE CLOSED LOW THROUGH THE SHORT TERM PERIOD WHICH WILL CONTINUE TO DRAW UP PACIFIC MOISTURE ACROSS OUR REGION. THE NORTHERN STREAM SHORTWAVE WILL TRACK EAST AND HELP SEND A WEAK COLD FRONT INTO OUR CWA LATER TODAY. SURFACE ANALYSIS STILL SHOWED A STALLED FRONTAL BOUNDARY ALONG HIGHWAY 84 THAT STRETCHED BACK ACROSS CENTRAL LOUISIANA AND INTO NORTHEAST TEXAS. A FEW LIGHT SHOWERS WILL BE POSSIBLE THIS MORNING IN OUR SOUTH TRACKING INTO CENTRAL MISSISSIPPI DUE TO THE STALLED BOUNDARY BUT THE GREATEST CHANCE FOR RAIN THIS MORNING WILL BE OVER OUR NORTHWEST ZONES AS MORE VIGOROUS CONVECTION HAS DEVELOPED OVERNIGHT ALONG AND NORTH OF THE STALLED FRONT OVER THE ARKLATEX. THIS ACTIVITY WILL SPREAD EAST INTO OUR AREA THIS MORNING. MODEL CONSENSUS MOVES THE WEAK COLD FRONT FROM THE NORTHWEST INTO OUR DELTA REGION THIS AFTERNOON AND IT IS EXPECTED TO HAVE ENOUGH MOMENTUM TO PUSH SOUTH OF OUR CWA LATE THIS EVENING BEFORE STALLING. THE FOCUS FOR RAIN WILL SHIFT SOUTH WITH THE FRONT THIS AFTERNOON AND EVENING. A WEAK CENTER OF HIGH PRESSURE WILL MOVE IN BEHIND THE FRONT TONIGHT AND BRING SLIGHTLY COOLER AND DRIER AIR TO THE LOW LEVELS. THIS WILL HELP BRING AN END TO THE RAIN LATE TONIGHT THAT WILL LAST INTO SATURDAY MORNING. THE RAIN WILL MOVE BACK OVER OUR CWA FROM THE SOUTHWEST SATURDAY AFTERNOON IN RESPONSE TO THE APPROACHING CLOSED LOW THAT WILL OPEN INTO AND UPPER LEVEL TROUGH OVER THE SOUTHERN PLAINS. THE STALLED FRONTAL BOUNDARY WILL BEGIN MOVING BACK TO THE NORTH BY SUNDAY MORNING AS WELL AIDING THE RAIN PRODUCTION. ONE TO TWO INCH RAIN AMOUNTS WILL BE COMMON OVER THE WESTERN HALF OF OUR CWA FROM TODAY THROUGH EARLY SUNDAY MORNING. /22/ .LONG TERM...SUNDAY THROUGH THURSDAY...WET WEATHER CONDITIONS WILL LINGER THROUGH THE END OF THE WEEKEND WITH A PERIOD OF DRIER WEATHER EXPECTED FOR THE BEGINNING OF THE WORK WEEK. ON SUNDAY MORNING THE UPPER TROUGH WILL BE POSITIONED ACROSS THE LOWER PLAINS WITH THE SURFACE LOW STILL WEST OF THE FORECAST AREA. THE 00Z GFS IS CONSIDERABLY SLOWER AND FARTHER NORTH/WEST WITH THE LOW COMPARED TO YESTERDAY. THE EURO...HOWEVER...HAS SHOWN GREATER CONSISTENCY OVER THE PAST FEW RUNS...AND THIS IS THE SOLUTION WE WILL PREFER FOR THIS PACKAGE. WHILE THIS WOULD STILL TRANSLATE INTO A SLOWER PROGRESSION OF THIS SYSTEM THROUGH THE REGION AND HIGHER QPF THROUGH THE DAY SUNDAY THAN INDICATED IN PREVIOUS FORECASTS...IT WOULD ALSO FAVOR CLEARING OUT FASTER THAN THE GFS. THUNDER STILL LOOKS QUITE POSSIBLE SUNDAY INTO SUNDAY EVENING...PARTICULARLY OVER THE SOUTHERN HALF OF THE AREA WHERE THERE WILL BE A GREATER POTENTIAL FOR LOW LEVEL DESTABILIZATION. MOST AVAILABLE GUIDANCE LIMITS SURFACE BASED INSTABILITY TO GENERALLY ALONG AND SOUTH OF THE I-20 CORRIDOR...WITH SOME ELEVATED INSTABILITY POSSIBLE A BIT FARTHER NORTH. THE MAIN FOCUS FOR THUNDER IN WX GRIDS SUNDAY/SUNDAY NIGHT WAS PLACED OVER THE SOUTHERN 2/3RDS OF THE CWA. THE UPPER TROUGH/SHORTWAVE IS EXPECTED TO SHIFT ACROSS THE AREA SUNDAY NIGHT/MONDAY MORNING...WITH UPPER FLOW BECOMING MORE ZONAL FOR THE EARLY PART OF NEXT WEEK. SURFACE RIDGING WILL SHIFT ACROSS THE REGION MONDAY INTO TUESDAY...BUT LOW LEVEL FLOW WILL QUICKLY SHIFT BACK AROUND TO SOUTHERLY TUESDAY INTO WEDNESDAY ALLOWING FOR A RETURN TO ABOVE NORMAL TEMPS. MODEL SOLUTIONS DIVERGE FOR THE MIDDLE TO END OF THE WEEK...BUT THERE IS SOME AGREEMENT THAT ANOTHER COLD FRONT WILL PUSH INTO THE AREA AROUND THURSDAY...WITH RAIN POSSIBLE OVER NORTHERN ZONES AS EARLY AS WEDNESDAY NIGHT. /DL/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 74 57 71 57 / 19 35 71 91 MERIDIAN 76 57 73 58 / 22 30 48 86 VICKSBURG 72 56 68 57 / 18 49 78 87 HATTIESBURG 81 62 76 60 / 17 49 76 84 NATCHEZ 78 59 70 58 / 17 65 80 89 GREENVILLE 65 52 68 54 / 19 17 45 77 GREENWOOD 66 53 69 53 / 24 14 37 77 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ 17/SW/22/DL/
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
251 PM CDT Fri Mar 20 2015 .SHORT TERM: (Through Tonight) Issued at 250 PM CDT Fri Mar 20 2015 Focus tonight will be temps. Clouds continue to struggle to dissipate this afternoon. It appears the RAP is handling these clouds the best for now. Nrn edge of the clouds shud continue slowly moving ewd. Further S, believe clouds will continue to dissipate and move newd. A section of the nrn clouds from near KCOU to KUIN will likely be the last to dissipate or advect out of the area. Across the srn portions of the CWA, CI has already begun to move into the area and will continue to do so overnight. However, it is a little uncertain how thick these clouds will be. Have trended twd the cooler guidance tonight partially because of anticipating the clearing. However, going forecast may not be cold enuf since temps struggled today. Tilly .LONG TERM: (Saturday through Next Friday) Issued at 250 PM CDT Fri Mar 20 2015 A cdfnt shud have arrived across the nrn third of the CWA by 12z Sat. This fnt will continue to push swd thru the day. While this may be a cold fnt, with nearly full insolation expected, tomorrow shud actually be warmer than today. Mdls also push the thermal ridge across the region on Sat. The fnt begins to lift nwd on Sun as a sfc low and associated s/w approach the region. While not high chances, this system will bring a chance for RA across nrn portions of the CWA Sun night and across much of the area on Mon, more probable during the afternoon with heating. As the trof deepens across the Plains and the LLJ increases with what shud be an open Gulf, precip chances increase quickly Mon night and Tues, with TS becoming more probable as well. Going forecast PoPs may be too low attm, but have not gone higher for now due to lack of persistence among mdl guidance. Given the amount of shear available with the system on Tues, there is a very narrow window where severe weather potential exists. However, given a number of questions regarding timing with this event, will hold off mention in products now other than that it remains to be a system to watch. Behind the cdfnt late Wed and a secondary cdfnt on Thurs, the potential for a very cold rain or possibly even light snow event exists. Have kept as RA for now, but again, will be a system to monitor. Tilly && .AVIATION: (For the 18z TAFs through 18z Saturday Afternoon) Issued at 1235 PM CDT Fri Mar 20 2015 Low stratus has been stuborn to clear/erode thus far and exact trends this afternoon are hardly high confidence. There have been indications of thinning and possible erosion from southwest MO into central MO towards the St. Louis area and also from the north out of Iowa. The new TAFS suggest these trends will persist and all sites that are still IFR should at leave improve to MVFR by 18-20z. I was a bit pessimistic on the clearing trend. I added a tempo for some light fog/BR into the St. Louis area terminals late tonight/early Saturday morning and this will be strongly dependent on how quickly the clearing progresses. The longer it takes the better the fog potential and severity. A cold front will move through the region on Saturday morning and flight conditions should be VFR at that time. Specifics for KSTL: Low stratus has been stuborn to clear/erode thus far and exact trends this afternoon are hardly high confidence. There have been indications of thinning and possible erosion from southwest MO into central MO towards the St. Louis area, and also to the south/southeast of KSTL. The new TAF suggest these trends will persist with improvement to VFR by 21z. I was a bit pessimistic on the clearing trend. I added a tempo for some light fog/BR late tonight/early Saturday morning and this will be strongly dependent on how quickly the clearing progresses. The longer it takes the better the fog potential and severity. A cold front will move through the region on Saturday morning and flight conditions should be VFR at that time. Glass && .PRELIMINARY POINT TEMPS/POPS: Saint Louis 44 71 43 69 / 0 0 0 5 Quincy 40 63 38 63 / 0 0 0 5 Columbia 43 71 44 72 / 0 0 0 5 Jefferson City 41 72 44 72 / 0 0 0 5 Salem 41 68 40 62 / 0 0 0 5 Farmington 42 72 42 69 / 0 0 0 10 && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1155 PM CDT Thu Mar 19 2015 .UPDATE: Issued at 959 PM CDT Thu Mar 19 2015 Updated the fcst mainly for PoPs. Nthrn band is working east as expected...while more activity works into SW MO from sthrn KS and nthrn OK. This should continue to push east and weaken with time. Removed the likely PoPs for the metro area overnight and kept the highest PoPs...in the high chance category...confined to areas south of I70. Otherwise the other fcst elements appear to be n good shape. 2% && .SHORT TERM: (Through Late Tonight) Issued at 342 PM CDT Thu Mar 19 2015 The combination of weak mid level frontogenesis, weak low-level convergence, and weak large scale ascent having been driving a band of rain from eastern KS across northern MO into west central IL for much of the afternoon. The band has managed to stay just north of Columbia for much of the day. Present indications are that as the attendant upstream shortwave migrates eastward this evening, the western portion of the band will sink a bit south and impact areas slight further south with likely or higher pops through mid-evening persisting in the north. Later tonight the RAP and HRRR have been very persistent for the last 4+ runs indicating another pocket of rain will move along and just north of I-44 moving into central MO around 05z and exiting the CWA by 10z. This appears to be in response to mid-level convergence and frontogenesis and looks quite reasonable, thus I have introduced some high chance to likely pops. Otherwise clouds/stratus will hang tuf with clearing across parts of central MO in the predawn hours, probably allowing for some fog. Glass .LONG TERM: (Friday through Next Thursday) Issued at 342 PM CDT Thu Mar 19 2015 Mdls are in relatively good agreement thru the forecast period. A cdfnt will drop into the region late Sat, bringing cooler temps for Sun. Ahead of the fnt, have trended aoa the warmer guidance, which is slightly warmer than the prev forecast. Mdls prog a s/w within the nrn branch approaching the region on Mon. Have kept PoPs low attm given the different mdl solns. For Tues, the GFS/GEM mdls suggest any precip will remain further W, with a more amplified flow and a more sly component of the LLJ. While the ECMWF soln is a possibility, this does not seem likely attm. With differences in sfc low track and strength of upper low, timing of precip for Wed and beyond is more difficult. Have kept PoPs out of the likely range for now given timing differences. However, it seems that precip will be likely sometime between Tues night and Thurs morning. Hopefully, timing will improve with future mdl cycles. Temps are expected to remain near or above seasonal average. Tilly && .AVIATION: (For the 06z TAFs through 06z Friday Night) Issued at 1155 PM CDT Thu Mar 19 2015 IFR CIGs will expand to the rest of STL metro by 08z, with improvement from west to east late tonight and into Friday morning as the low clouds slowly clear out. Rain should be done, but cannot fully rule out a brief occurrence of drizzle thru 12z. Otherwise, a light westerly flow will develop and back SW Friday night. Specifics for KSTL: Deteriorating conditions to IFR are imminent with some drizzle possible. Then improving conditions late Friday morning and early afternoon. A westerly flow will develop on Friday backing SW Friday night. TES && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
118 PM CDT FRI MAR 20 2015 .SYNOPSIS... ISSUED AT 351 AM CDT FRI MAR 20 2015 CUTOFF LOW OVER THE BAJA...RIDGING INTO THE PACIFIC NORTHWEST AND THE SOUTHEAST CONUS WITH AN UPPER HIGH OVER CUBA. TROUGH FROM HUDSON BAY LOW INTO THE OHIO VALLEY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 351 AM CDT FRI MAR 20 2015 MODELS IN FAIR AGREEMENT IN NEAR TERM. HAVE GOOD CONFIDENCE IN THE FORECAST. MAIN CONCERNS WILL BE FIRE WEATHER CONDITIONS OVER WESTERN NEBRASKA TODAY...SEE DISCUSSION BELOW. SPLIT FLOW REGIME ALOFT WITH STRONG SUBSIDENCE OVER WESTERN NEBRASKA TODAY. CLEAR SKIES FULL SUN AND GUSTY SOUTHWEST FLOW. HAVE UPPED TEMPERATURES BY 3 TO 4 DEGREES ABOVE GUIDANCE WITH STRONG WEST TO SOUTHWEST FLOW. LOWERED DEWPOINTS INTO THE TEENS OVER MUCH OF THE SANDHILLS AND SOUTHWEST NEBRASKA FOLLOWING RUC FORECAST. DEWPOINTS OVER THE PANHANDLE IN THE TEENS EARLY THIS MORNING. UNDER CLEAR SKIES TEMPERATURES WILL REMAIN IN THE 30S OVER NIGHT WITH SOME LOWER READINGS ALONG RIVER VALLEYS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 351 AM CDT FRI MAR 20 2015 ACTIVE PATTERN FOR THE LONG TERM PERIOD. MAIN FOCUS WILL BE ON AND OFF FIRE CONCERNS AND MODEL DIFFERENCES WITH A FEW SHOTS AT RAINFALL/THUNDER...YES PRECIP...NEXT WEEK...ALBEIT NOT GREAT SHOTS. SATURDAY A STALLING COOL FRONT WILL BEGIN TO PUSH BACK TO THE NORTHEAST AS A WARM FRONT. QUESTION IS HOW FAR IT MAKES IT INTO N CENTRAL NEB AS TO TEMPS THERE. TO THE SOUTHWEST OF THE FRONT...850 MB TEMPS SOAR BACK TO 14C TO 18C. GUIDANCE RETURNS TEMPS INTO THE MID TO UPPER 70S. WITH LITTLE CLOUD COVER EXPECTED...HAVE SIDED WITH THE WARMER VALUES. TO THE NORTHEAST OF THE FRONT...STILL MILD AIR FOR FEBRUARY WITH HIGHS IN THE 60S. WINDS TO THE SOUTHWEST OF THE FRONT WILL BE FAIRLY LIGHT...15 MPH OR LESS...SO WHILE RH VALUES WILL BE AT OR BELOW CRITICAL LEVELS NO HEADLINE AT THIS TIME. SUNDAY A SFC LOW AND TRAILING COLD FRONT WILL SLIDE SE ACROSS THE AREA. TIMING STILL IN QUESTION WITH THE GFS FASTER...BRINGING COLD AIR CLOSER TO THE CWA....WHICH MAKES FOR A LOW CONFIDENCE TEMP FORECAST. MIXING ALONG THE FRONT SHOULD HELP TO PUSH TEMPS UP SO STILL WENT WITH 60S AND 70S AGAIN. MODELS IN GENERALLY HAVE INCREASE THE ARRIVAL OF THE FRONT...WHICH HAS RESULTED IN THE BETTER MOISTURE/LIFT FOCUSING MAINLY TO THE NORTH AND EAST OF THE CWA...SO TRIMMED INHERITED POPS. MONDAY THROUGH WEDNESDAY A SERIES OF DISTURBANCES WILL PUSH ACROSS THE PLAINS...HOWEVER MODELS CONTINUE TO STRUGGLE WITH THE TRACK AND TIMING. THE FIRST WAVE ARRIVES MONDAY MORNING. DRY SLOT ACROSS SW WITH THE REST OF THE AREA WITH LOW POPS. SOUTHERLY WINDS WILL BE INCREASING MOISTURE...HOWEVER WOULD NOT BE SURPRISED MOST OF THE PRECIP IS JUST LIGHT RAIN OR SPRINKLES. MONDAY NIGHT THE GFS FAVORS AN ELEVATED TROUGH TO LIFT NE ACROSS THE AREA. A NEG ELEVATED LIFTED INDEX AND MARGINAL MOISTURE COULD RESULT IN SOME OVERNIGHT THUNDER. LINGERING T CHANCE FOR TUESDAY AS THE ACTIVITY LIFTS NE OF THE AREA. WEDNESDAY A STRONGER LOW SLIDES ACROSS THE NORTHERN/CENTRAL PLAINS...WITH A TRAILING COLD FRONT. SOME ARCTIC AIR FILLS IN BEHIND THE FRONT AS 850 MB TEMPS FALL BELOW ZERO. LACK OF MOISTURE IS STILL A CONCERN WITH PASSAGE...HOWEVER THE COOLER TEMPS COULD RESULT IN RAIN MAYBE MIXING WITH SNOW WED NIGHT IF IT HAS NOT EXITED YET. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 114 PM CDT FRI MAR 20 2015 A FEW SCATTERED HIGH CIRRUS CLOUDS WILL OCCUR THIS AFTERNOON...OTHERWISE CLEAR SKIES CAN BE EXPECTED. VFR CONDITIONS WILL PREVAIL THROUGH TONIGHT. WEST TO NORTHWEST WINDS AT 10 TO 20 KTS THIS AFTERNOON WILL DECREASE TO 5 KTS OR LESS TONIGHT. && .FIRE WEATHER... ISSUED AT 351 AM CDT FRI MAR 20 2015 CRITICAL FIRE WEATHER DAY OVER WESTERN NEBRASKA WHERE MOISTURE HAS BEEN SPARSE OVER THE LAST MONTH. WEST TO SOUTHWEST FLOW TODAY WITH DEW POINTS FALLING INTO THE TEENS AND SURFACE TEMPERATURES RISING INTO THE MID 70S THIS AFTERNOON. NORTHEAST ZONES WILL BE MORE SUSCEPTIBLE WITH STRONGER WIND FORECAST AS COOL FRONT MOVES SOUTH OUT OF SOUTH DAKOTA THIS EVENING. WINDS SOMEWHAT MARGINAL OVER THE SOUTHEAST NEBRASKA PANHANDLE AND SOUTHWEST NEBRASKA BUT HAVE INCLUDED DUE TO LOW RH AND VERY DRY CONDITIONS. && .LBF WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 8 PM CDT /7 PM MDT/ THIS EVENING FOR NEZ204-206-208>210-219. && $$ SYNOPSIS...POWER SHORT TERM...POWER LONG TERM...MASEK AVIATION...TAYLOR FIRE WEATHER...POWER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1223 PM CDT FRI MAR 20 2015 .UPDATE... ISSUED AT 651 AM CDT FRI MAR 20 2015 WITHIN THE LAST FEW HOURS...MADE A FEW UPDATES FOR THIS MORNING`S FORECAST MAINLY ADDRESSING TWO ITEMS: 1) ALTHOUGH APPARENTLY QUITE SMALL IN AREAL EXTENT...AUTOMATED OBS...SATELLITE IMAGERY AND GROUND TRUTH INCLUDING SOCIAL MEDIA REPORTS INDICATE THAT AT LEAST LOCALIZED DENSE FOG HAS IN FACT BECOME AN ISSUE THIS MORNING...PRIMARILY ONLY IN MITCHELL COUNTY KS AND POSSIBLY IN IMMEDIATELY-BORDERING PORTIONS OF NEIGHBORING COUNTIES. CONTEMPLATED ISSUING A 1-COUNTY DENSE FOG ADVISORY BUT AFTER COORDINATING WITH NEIGHBORING OFFICES ICT/TOP OPTED TO HOLD OFF ON ANY FORMAL HEADLINE...BUT DID ISSUE A SPECIAL WEATHER STATEMENT (SPSGID) CONCERNING THIS FOG THROUGH 9 AM. 2) LOW TEMPS THIS MORNING CONTINUE TO DROP A TOUCH LOWER THAN EXPECTED...AND IT NOW APPEARS MOST OF THE CWA WILL BOTTOM OUT IN THE 23-28 RANGE...WITH TYPICAL COLD SPOTS SUCH AS ORD NOW DOWN TO 20. ASSUMING THE AFTERNOON HIGH TEMP FORECAST IS ON TRACK...WE ARE IN FOR A NOTABLE 40-50 DEGREE DIURNAL TEMP RISE TODAY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 359 AM CDT FRI MAR 20 2015 IF NOT FOR THE NOW-CRITICAL FIRE DANGER CONCERNS MAINLY NORTH OF THE INTERSTATE 80 CORRIDOR THIS AFTERNOON...THIS WOULD ACTUALLY BE A FAIRLY STRAIGHTFORWARD 24 HOURS WITH ESSENTIALLY CLOUD-FREE SKIES...EFFECTIVELY ZERO RISK OF PRECIP...AND A NICE WARM UP INTO THE 70S AREA-WIDE. ABOUT THE ONLY THING THAT MIGHT WARRANT A COMPLAINT WOULD BE SOMEWHAT BREEZY WESTERLY WIND THIS AFTERNOON...ESPECIALLY NEAR/NORTH OF I-80. FOR THOSE WITH PARTICULAR INTEREST IN THE FIRE DANGER DETAILS TODAY...PLEASE REFER TO THE SEPARATE SECTION BELOW AS THIS TOPIC WILL NOT BE ADDRESSED ANY FURTHER IN THIS MAIN SHORT TERM SECTION. STARTING OFF WITH THE HERE AND NOW AS OF 08Z/3AM...THE ENTIRE CWA SITS UNDER ESSENTIALLY CLOUDLESS SKIES AS THE MASS OF CLOUDS FROM YESTERDAY HAS SUNK WELL OFF TO THE SOUTH. ALTHOUGH THE MAJORITY OF THE CWA IS TRULY FREE OF ALL WEATHER CONCERNS...AN AREA OF HIGHER DEWPOINTS AROUND 30 DEGREES RESIDING NEAR A SUBTLE TROUGH AXIS IN FAR SOUTHEAST COUNTIES SUCH AS THAYER/JEWELL/MITCHELL IS PROMOTING AT LEAST SOME PATCHY LIGHT FOG...WITH THE BELOIT AIRPORT EVEN SUGGESTING IT COULD BE PATCHY DENSE ESPECIALLY IN LOW-LYING AREAS. THANKS TO THE CLEAR SKIES AND A GENERALLY LIGHT/VARIABLE WIND REGIME WITH SUSTAINED SPEEDS LARGELY AROUND 5 MPH OR LESS...TEMPS THIS MORNING ARE DROPPING A BIT LOWER THAN ANTICIPATED IN MANY AREAS...AS IT NOW APPEARS THE MAJORITY OF THE CWA SHOULD BOTTOM OUT SOMEWHERE IN THE 25-32 RANGE. TURNING TO THE MID-UPPER LEVELS...THE LOCAL AREA REMAINS UNDER RATHER WEAK FLOW THANKS TO BEING WELL-REMOVED FROM BOTH THE NORTHERN AND SOUTHERN UPPER JET BRANCHES IN THIS LARGE-SCALE SPLIT FLOW REGIME...WITH THE NORTHERN BRANCH CENTERED MAINLY FROM CANADA INTO THE DAKOTAS...AND THE SOUTHERN BRANCH ORIENTED FROM MEXICO INTO THE SOUTHERN PLAINS AND EASTWARD. NOW LOOKING AHEAD FORECAST-WISE... EARLY THIS MORNING (ROUGHLY THROUGH 8 AM): AS MENTIONED ABOVE ABOUT THE ONLY CONCERN IS THE ONGOING POTENTIAL FOR AT LEAST PATCHY FOG MAINLY SOUTHEAST OF A HEBRON-OSBORNE LINE WHERE MOISTURE REMAINS HIGHER ALONG THE WEAK TROUGH AXIS. ALTHOUGH CERTAINLY NOT EXPECTING WIDESPREAD DENSE FOG ISSUES AT THIS POINT...PATCHY DENSE IS NOT OUT OF THE QUESTION AND MAY ADD THIS MENTION TO THE HAZARDOUS WEATHER OUTLOOK (HWOGID). FOR WHAT ITS WORTH...THE LATEST 07Z HRRR VISIBILITY PROG HAS CAUGHT ONTO THIS SMALL-SCALE AREA OF AT LEAST LIGHT FOG POTENTIAL. TODAY: ONCE ANY LINGERING MORNING FOG BURNS OFF IN THE SOUTHEAST...BY MOST FOLKS STANDARDS WE ARE LEFT WITH A PRETTY DARN PLEASANT DAY WITH A BIT OF BREEZE (ESPECIALLY NORTH) AND ESSENTIALLY WALL-TO-WALL SUNSHINE. IN THE MID-UPPER LEVELS...ESSENTIALLY NIL FORCING IN FAIRLY WEAK WEST-NORTHWEST FLOW AS THE LOCAL AREA REMAINS IN THE "QUIET ZONE" BETWEEN THE MAIN JET BRANCHES IN THE SPLIT REGIME. AT THE SURFACE...WEAK PRESSURE FALLS ASSOCIATED WITH A WEAK LOW PRESSURE SYSTEM SLIDING EAST-SOUTHEAST ACROSS THE DAKOTAS...ALONG WITH BROAD HIGH PRESSURE CENTERED TO THE SOUTH...WILL PROMOTE INCREASING WEST-SOUTHWEST BREEZES AS THE DAY WEARS ON. THESE BREEZES WILL PEAK IN INTENSITY THIS AFTERNOON THANKS TO DEEP DIURNAL MIXING PROGGED TO REACH UP TO AROUND 750 MILLIBARS PER GFS FORECAST SOUNDINGS. WITH THE STRONGEST CORRIDOR OF LOW-LEVEL WINDS FOCUSED NORTH OF I-80...THAT IS WHERE THE OVERALL-STRONGEST SUSTAINED SPEEDS OF AROUND 20 MPH WITH HIGHER GUSTS CLOSER TO 30 MPH WILL EXIST...WITH SPEEDS TAPERING OFF GRADUALLY WITH SOUTHWARD EXTENT...AND THUS KS ZONES ONLY EXPECTED TO SEE SUSTAINED SPEEDS AROUND 10 MPH. GIVEN THE DEEP MIXING ANTICIPATED...YET AGAIN AND AS HAS BEEN THE CASE ON SEVERAL DAYS THIS MONTH...VARIOUS SETS OF MODELS/GUIDANCE APPEAR TO BE TOO HIGH WITH AFTERNOON DEWPOINTS/RELATIVE HUMIDITY VALUES. ALTHOUGH MAY HAVE NOT GONE LOW ENOUGH...FOLLOWED CLOSEST TO GFS/RAP VALUES WITH DEWS AVERAGING WELL DOWN IN THE 20S CWA-WIDE FOR MOST OF THE DAY. TEMP-WISE...THIS SUNNY/DOWNSLOPE WESTERLY WIND REGIME SHOULD SQUEEZE OUT EVERY BIT OF WARMING POTENTIAL THAT IT CAN...AND NUDGED HIGH TEMPS OVER MUCH OF THE CWA UP ANOTHER 1-2 DEGREES...AIMING FOR A FAIRLY UNIFORM 73-75 RANGE MOST PLACES. BY VERY LATE THIS AFTERNOON (ESPECIALLY AFTER 6 PM)...THE AFTERNOON BREEZINESS SHOULD BE ON A FAIRLY STEADY DECLINE. THIS EVENING/TONIGHT: QUIET/ESSENTIALLY CLOUD-FREE WEATHER PERSISTS OVER THE LOCAL AREA IN WEAK QUASI-ZONAL FLOW ALOFT. AT THE SURFACE...HIGH PRESSURE WILL INCREASINGLY-BUILD SOUTHWARD INTO NEBRASKA AS THE NIGHT WEARS ON...EMANATING FROM A HIGH PRESSURE SYSTEM EXTENDING SOUTHWARD FROM THE CANADA/NORTH DAKOTA/MINNESOTA BORDER REGION. ALL THIS REALLY MEANS LOCALLY IS THAT WHILE THE EVENING HOURS WILL GENERALLY FEATURE SOUTH-SOUTHWEST BREEZES OF 5-10 MPH...THE POST-MIDNIGHT HOURS WILL BRING A WEAK COLD FRONT SOUTHWARD MAINLY INTO THE NORTHERN 1/2 OF THE CWA...MARKED BY A SWITCH TO FAIRLY LIGHT NORTH/NORTHEAST BREEZES. GIVEN THE CLEAR SKIES AND LIGHT BREEZES...WE MAY BE FACING ANOTHER NIGHT WITH TEMPS FALLING A BIT LOWER THAN CURRENT EXPECTATIONS...BUT GIVEN THE NOTICEABLY WARMER START TO THE NIGHT THIS TIME AROUND...GENERALLY EXPECT LOWS TO HOLD UP ABOUT 5-8 DEGREES WARMER THAN THIS MORNING. AS A RESULT...HAVE LOWS AIMED 35-39 ACROSS MOST OF THE CWA...AND COLDER LOW 30S MOST FAVORED IN THE USUAL VALLEY/GREELEY/DAWSON COUNTY AREAS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 359 AM CDT FRI MAR 20 2015 ACTUALLY A DECENT AMOUNT OF INTERESTING WEATHER IN THE EXTENDED PERIOD. IN GENERAL...TEMPERATURES REMAIN WELL ABOVE NORMAL THROUGH TUESDAY...AND THEN START TO COOL BACK TO NEAR SEASONAL NORMALS WEDNESDAY AND THURSDAY. PRECIPITATION CHANCES CENTERED ON MONDAY NIGHT. THOUGH SPRING STARTS TODAY AT 2245Z...SATURDAY WILL BE THE FIRST FULL DAY OF SPRING AND IT WILL BE A NICE ONE. HIGHS IN THE 70S AND REASONABLY LIGHT SOUTH WINDS. LOW LEVEL MOISTURE STARTS TO SNEAK UP INTO THE AREA BY SUNDAY MORNING...WITH DEWPOINTS WELL INTO THE 40S EXPECTED OVER PARTS OF THE AREA SUNDAY. ALL THIS IS AHEAD OF A WEAK SURFACE FRONT. THE FRONT WILL BE A FOCUS FOR LOW LEVEL CONVERGENCE...AND THE INCREASING MOISTURE RESULTS IN SOME 500+ CAPE VALUES BY AFTERNOON. MODEL TRENDS HAVE SLID THE CONVECTIVE POTENTIAL TO THE EAST...OR MAINLY EAST OF HIGHWAY 81. THERE IS GOOD AGREEMENT WITH THE MODELS THIS EVENT WILL BE GET GOING FURTHER EAST AND LATER IN THE EVENING. FOR THAT REASON HAVE TRIMMED THUNDERSTORM CHANCES BACK AND HUGGED THE EASTERN EDGE OF THE FORECAST AREA. THIS WINDOW OF OPPORTUNITY LOOKS PRETTY SMALL BOTH TIMING AND COVERAGE WISE AT THIS TIME. ATTENTION TURNS TO MONDAY AND TUESDAY...WHEN A WEAK SHORT WAVE WILL RIDE OVER AN UPPER LEVEL RIDGE. WARM ADVECTION WILL ALSO KICK IN AND THERE IS SOMEWHAT IMPROVING CHANCES FOR SHOWERS AND ISOLATED THUNDERSTORMS MOVING INTO FROM THE SOUTH MONDAY AND SPREADING OVER MOST OF THE AREA MONDAY NIGHT AND THE FIRST HALF OF THE DAY TUESDAY. MID LEVEL LAPSE RATES ARE ACTUALLY PRETTY UNSTABLE MONDAY NIGHT AS LOW LEVEL MOISTURE CREEPS BACK INTO THE AREA. SOME WEAK ELEVATED CAPE ALSO SUPPORTS AT LEAST ISOLATED THUNDERSTORMS. STILL A FEW DAYS AWAY...BUT THERE IS AT LEAST SOME CHANCE OF MEASURABLE RAINFALL FOR MOST AREAS... ESPECIALLY MONDAY NIGHT AND EARLY TUESDAY. SIGNS NOW POINT TOWARD AMOUNTS IN THE 0.15 TO 0.35 RANGE...BUT IT IS EARLY. ALL OF THE PRECIPITATION LIFTS NORTHEAST OF THE REGION BY ABOUT MIDDAY TUESDAY AS UPPER LEVEL LOW PRESSURE DEEPENS TO OUR NORTH IN THE DAKOTAS. SUCH A LOW POSITION HAS SOME POTENTIAL TO SWEEP SOME DRY AIR ACROSS THE FORECAST AREA TUESDAY AFTERNOON ABOARD WESTERLY WINDS. SO DESPITE SOME RAINFALL POTENTIALLY EARLY IN THE DAY...THE RAPID DRYING MAY BE A FIRE WEATHER ISSUE LATE THE AFTERNOON FOR SOME AREAS. SEE THE FIRE WEATHER DISCUSSION FOR MORE INFORMATION. TUESDAY LOOKS LIKE THE LAST WELL ABOVE NORMAL DAY FOR TEMPERATURES AS COOLER AIR INVADES THE REGION BY WEDNESDAY AND LINGERS INTO THURSDAY. GOOD NEWS IS THE COOLER TEMPS ARE REALLY ONLY ABOUT NORMAL AT THE COOLEST. PEERING AHEAD A BIT FURTHER...WHATEVER RAIN WE MAY GET EARLY NEXT WEEK COULD BE PRETTY HANDY...AS THE LIKELIHOOD OF ANY OTHER SUBSTANTIAL RAINFALL PRIOR TO THE END OF THE MONTH LOOKS IFFY AT BEST. TEMPERATURES MAY CLIMB BACK ABOVE NORMAL AGAIN BY NEXT WEEKEND. && .AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1213 PM CDT FRI MAR 20 2015 A SURFACE HIGH PRESSURE IS SLIDING TO THE SOUTH. WEST WINDS ARE PICKING UP THIS AFTERNOON AND WILL DIMINISH AS THE SUN SETS TONIGHT. && .FIRE WEATHER... ISSUED AT 359 AM CDT FRI MAR 20 2015 THIS AFTERNOON/EARLY EVENING: NOT SURPRISING GIVEN TRENDS OVER THE PAST FEW DAYS...TODAY IS NOW OFFICIALLY CONSIDERED A CRITICAL FIRE DANGER DAY FOR MOST COUNTIES ALONG/NORTH OF THE INTERSTATE 80 CORRIDOR...AND HAVE COORDINATED WITH NEIGHBORING OFFICES LBF/OAX ON AN UPGRADE/EXPANSION OF THE PREVIOUS FIRE WEATHER WATCH TO A RED FLAG WARNING VALID FROM 18Z- 01Z/1PM-8PM. JUST AS A QUICK REVIEW FOR THOSE WHO MIGHT BE UNFAMILIAR WITH FIRE WEATHER CRITERIA: "CRITICAL" FIRE WEATHER IN OUR CWA IS DEFINED AS THE 3+ HOUR OVERLAP OF RELATIVE HUMIDITY (RH) OF 20 PERCENT-OR-LOWER AND SUSTAINED WINDS/GUSTS OF 20 MPH/25 MPH. "NEAR-CRITICAL" IS DEFINED AS THE OVERLAP OF 25 PERCENT-OR- LOWER RH AND SUSTAINED WINDS GUSTS OF 15 MPH/20 MPH (IN THE PRESENCE OF DRY VEGETATION OF COURSE). WITHIN THE WARNING AREA...CONFIDENCE HAS INCREASED IN REACHING CRITICAL CRITERIA...WITH RH VALUES EXPECTED TO SOLIDLY CRASH INTO THE 14-20 PERCENT RANGE FOR SEVERAL HOURS. WIND-WISE...ALTHOUGH SOME PLACES IN THE WARNING MAY NOT SEE WIDESPREAD 20+ MPH SUSTAINED WESTERLY SPEEDS ALL AFTERNOON...THERE SHOULD BE A GREATER LIKELIHOOD OF REALIZING SEMI-FREQUENT 25+ MPH GUSTS GIVEN DEEP MIXING...ESPECIALLY NORTH OF HIGHWAY 92. OF COURSE...IT IS ALWAYS IMPORTANT TO REMEMBER THAT EVEN OUTSIDE THE OFFICIAL RED FLAG AREA...AT LEAST NEAR-CRITICAL FIRE DANGER WILL CERTAINLY EXIST...ESPECIALLY FOR COUNTIES BETWEEN I-80 AND THE STATE LINE WHERE GUST POTENTIAL TO 20+ MPH SHOULD EXIST. ALTHOUGH NOT "TOTALLY SAFE" BY ANY MEANS...NORTH CENTRAL KANSAS ZONES SHOULD BE UNDER THE LEAST-OVERALL THREAT THIS AFTERNOON GIVEN THAT EVEN GUSTS SHOULD FALL SHORT OF 20 MPH. ON ONE LAST NOTE...THE WARNING END TIME OF 8PM IS PROBABLY PLENTY GENEROUS GIVEN THAT WIND SPEEDS SHOULD REALLY SLACKEN CONSIDERABLY BY 7PM IF NOT SOONER...BUT GIVEN HOW LOW RH VALUES SHOULD DROP...WOULD RATHER GIVE LATER SHIFTS A CHANCE TO CANCEL A BIT EARLY THAN HAVE TO EXTEND. BEYOND TODAY: DESPITE THE FACT THERE ARE AT LEAST SMALL CHANCES FOR PRECIPITATION PEPPERED IN THE LATE SUNDAY THROUGH WEDNESDAY TIMEFRAME...THERE COULD BE A COUPLE OF PERIODS OF HEIGHTENED FIRE WEATHER CONDITIONS. SATURDAY WILL SEE SOME PRETTY LOW RELATIVE HUMIDITY VALUES IN THE SOUTHWEST...BUT THE WIND SHOULD REMAIN BELOW 15 MPH. ANOTHER MAY BE SUNDAY AFTERNOON ACROSS ABOUT THE WESTERN HALF OF THE FORECAST AREA. DRIER AIR WILL FILTER IN AS A NORTHWEST WIND TAKES HOLD IN A POST FRONT REGIME. TEMPS WILL BE WELL ABOVE NORMAL AGAIN. WIND SPEEDS ARE A BIT MARGINAL AND IT WILL BE TOTALLY BASED ON TIMING. SIMILAR DEAL ON TUESDAY BUT THIS TIME STRONG UPPER LEVEL LOW PRESSURE OVER THE DAKOTAS WILL HELP CREATE A DOWNSLOPE WESTERLY FLOW BY AFTERNOON...AGAIN OVER THE WESTERN HALF OF THE FORECAST. IT DOESN/T LOOK AS WARM BUT SURFACE DEWPOINTS COULD REALLY TANK...POSSIBLY WELL BELOW THE ONGOING FORECAST. AGAIN... TIMING IS THE KEY AND THIS PERIOD SHOULD BE CONSIDERED ONE TO WATCH AS THE TIME APPROACHES. && .GID WATCHES/WARNINGS/ADVISORIES... NE...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ039>041- 046>049-060>063. KS...NONE. && $$ UPDATE...PFANNKUCH SHORT TERM...PFANNKUCH LONG TERM...MORITZ AVIATION...JCB FIRE WEATHER...PFANNKUCH/MORITZ
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
700 AM CDT FRI MAR 20 2015 .SYNOPSIS... ISSUED AT 351 AM CDT FRI MAR 20 2015 CUTOFF LOW OVER THE BAJA...RIDGING INTO THE PACIFIC NORTHWEST AND THE SOUTHEAST CONUS WITH AN UPPER HIGH OVER CUBA. TROUGH FROM HUDSON BAY LOW INTO THE OHIO VALLEY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 351 AM CDT FRI MAR 20 2015 MODELS IN FAIR AGREEMENT IN NEAR TERM. HAVE GOOD CONFIDENCE IN THE FORECAST. MAIN CONCERNS WILL BE FIRE WEATHER CONDITIONS OVER WESTERN NEBRASKA TODAY...SEE DISCUSSION BELOW. SPLIT FLOW REGIME ALOFT WITH STRONG SUBSIDENCE OVER WESTERN NEBRASKA TODAY. CLEAR SKIES FULL SUN AND GUSTY SOUTHWEST FLOW. HAVE UPPED TEMPERATURES BY 3 TO 4 DEGREES ABOVE GUIDANCE WITH STRONG WEST TO SOUTHWEST FLOW. LOWERED DEWPOINTS INTO THE TEENS OVER MUCH OF THE SANDHILLS AND SOUTHWEST NEBRASKA FOLLOWING RUC FORECAST. DEWPOINTS OVER THE PANHANDLE IN THE TEENS EARLY THIS MORNING. UNDER CLEAR SKIES TEMPERATURES WILL REMAIN IN THE 30S OVER NIGHT WITH SOME LOWER READINGS ALONG RIVER VALLEYS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 351 AM CDT FRI MAR 20 2015 ACTIVE PATTERN FOR THE LONG TERM PERIOD. MAIN FOCUS WILL BE ON AND OFF FIRE CONCERNS AND MODEL DIFFERENCES WITH A FEW SHOTS AT RAINFALL/THUNDER...YES PRECIP...NEXT WEEK...ALBEIT NOT GREAT SHOTS. SATURDAY A STALLING COOL FRONT WILL BEGIN TO PUSH BACK TO THE NORTHEAST AS A WARM FRONT. QUESTION IS HOW FAR IT MAKES IT INTO N CENTRAL NEB AS TO TEMPS THERE. TO THE SOUTHWEST OF THE FRONT...850 MB TEMPS SOAR BACK TO 14C TO 18C. GUIDANCE RETURNS TEMPS INTO THE MID TO UPPER 70S. WITH LITTLE CLOUD COVER EXPECTED...HAVE SIDED WITH THE WARMER VALUES. TO THE NORTHEAST OF THE FRONT...STILL MILD AIR FOR FEBRUARY WITH HIGHS IN THE 60S. WINDS TO THE SOUTHWEST OF THE FRONT WILL BE FAIRLY LIGHT...15 MPH OR LESS...SO WHILE RH VALUES WILL BE AT OR BELOW CRITICAL LEVELS NO HEADLINE AT THIS TIME. SUNDAY A SFC LOW AND TRAILING COLD FRONT WILL SLIDE SE ACROSS THE AREA. TIMING STILL IN QUESTION WITH THE GFS FASTER...BRINGING COLD AIR CLOSER TO THE CWA....WHICH MAKES FOR A LOW CONFIDENCE TEMP FORECAST. MIXING ALONG THE FRONT SHOULD HELP TO PUSH TEMPS UP SO STILL WENT WITH 60S AND 70S AGAIN. MODELS IN GENERALLY HAVE INCREASE THE ARRIVAL OF THE FRONT...WHICH HAS RESULTED IN THE BETTER MOISTURE/LIFT FOCUSING MAINLY TO THE NORTH AND EAST OF THE CWA...SO TRIMMED INHERITED POPS. MONDAY THROUGH WEDNESDAY A SERIES OF DISTURBANCES WILL PUSH ACROSS THE PLAINS...HOWEVER MODELS CONTINUE TO STRUGGLE WITH THE TRACK AND TIMING. THE FIRST WAVE ARRIVES MONDAY MORNING. DRY SLOT ACROSS SW WITH THE REST OF THE AREA WITH LOW POPS. SOUTHERLY WINDS WILL BE INCREASING MOISTURE...HOWEVER WOULD NOT BE SURPRISED MOST OF THE PRECIP IS JUST LIGHT RAIN OR SPRINKLES. MONDAY NIGHT THE GFS FAVORS AN ELEVATED TROUGH TO LIFT NE ACROSS THE AREA. A NEG ELEVATED LIFTED INDEX AND MARGINAL MOISTURE COULD RESULT IN SOME OVERNIGHT THUNDER. LINGERING T CHANCE FOR TUESDAY AS THE ACTIVITY LIFTS NE OF THE AREA. WEDNESDAY A STRONGER LOW SLIDES ACROSS THE NORTHERN/CENTRAL PLAINS...WITH A TRAILING COLD FRONT. SOME ARCTIC AIR FILLS IN BEHIND THE FRONT AS 850 MB TEMPS FALL BELOW ZERO. LACK OF MOISTURE IS STILL A CONCERN WITH PASSAGE...HOWEVER THE COOLER TEMPS COULD RESULT IN RAIN MAYBE MIXING WITH SNOW WED NIGHT IF IT HAS NOT EXITED YET. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 700 AM CDT FRI MAR 20 2015 VISUAL FLIGHT RULES TODAY. MAIN AVIATION CONCERNS WILL CENTER ON WEST WINDS GUSTING TO 25 MPH AS WINDS INCREASE THIS MORNING. && .FIRE WEATHER... ISSUED AT 351 AM CDT FRI MAR 20 2015 CRITICAL FIRE WEATHER DAY OVER WESTERN NEBRASKA WHERE MOISTURE HAS BEEN SPARSE OVER THE LAST MONTH. WEST TO SOUTHWEST FLOW TODAY WITH DEW POINTS FALLING INTO THE TEENS AND SURFACE TEMPERATURES RISING INTO THE MID 70S THIS AFTERNOON. NORTHEAST ZONES WILL BE MORE SUSCEPTIBLE WITH STRONGER WIND FORECAST AS COOL FRONT MOVES SOUTH OUT OF SOUTH DAKOTA THIS EVENING. WINDS SOMEWHAT MARGINAL OVER THE SOUTHEAST NEBRASKA PANHANDLE AND SOUTHWEST NEBRASKA BUT HAVE INCLUDED DUE TO LOW RH AND VERY DRY CONDITIONS. && .LBF WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ THIS AFTERNOON TO 8 PM CDT /7 PM MDT/ THIS EVENING FOR NEZ204-206-208>210-219. && $$ SYNOPSIS...POWER SHORT TERM...POWER LONG TERM...MASEK AVIATION...POWER FIRE WEATHER...POWER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
651 AM CDT FRI MAR 20 2015 .UPDATE... ISSUED AT 651 AM CDT FRI MAR 20 2015 WITHIN THE LAST FEW HOURS...MADE A FEW UPDATES FOR THIS MORNING`S FORECAST MAINLY ADDRESSING TWO ITEMS: 1) ALTHOUGH APPARENTLY QUITE SMALL IN AREAL EXTENT...AUTOMATED OBS...SATELLITE IMAGERY AND GROUND TRUTH INCLUDING SOCIAL MEDIA REPORTS INDICATE THAT AT LEAST LOCALIZED DENSE FOG HAS IN FACT BECOME AN ISSUE THIS MORNING...PRIMARILY ONLY IN MITCHELL COUNTY KS AND POSSIBLY IN IMMEDIATELY-BORDERING PORTIONS OF NEIGHBORING COUNTIES. CONTEMPLATED ISSUING A 1-COUNTY DENSE FOG ADVISORY BUT AFTER COORDINATING WITH NEIGHBORING OFFICES ICT/TOP OPTED TO HOLD OFF ON ANY FORMAL HEADLINE...BUT DID ISSUE A SPECIAL WEATHER STATEMENT (SPSGID) CONCERNING THIS FOG THROUGH 9 AM. 2) LOW TEMPS THIS MORNING CONTINUE TO DROP A TOUCH LOWER THAN EXPECTED...AND IT NOW APPEARS MOST OF THE CWA WILL BOTTOM OUT IN THE 23-28 RANGE...WITH TYPICAL COLD SPOTS SUCH AS ORD NOW DOWN TO 20. ASSUMING THE AFTERNOON HIGH TEMP FORECAST IS ON TRACK...WE ARE IN FOR A NOTABLE 40-50 DEGREE DIURNAL TEMP RISE TODAY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 359 AM CDT FRI MAR 20 2015 IF NOT FOR THE NOW-CRITICAL FIRE DANGER CONCERNS MAINLY NORTH OF THE INTERSTATE 80 CORRIDOR THIS AFTERNOON...THIS WOULD ACTUALLY BE A FAIRLY STRAIGHTFORWARD 24 HOURS WITH ESSENTIALLY CLOUD-FREE SKIES...EFFECTIVELY ZERO RISK OF PRECIP...AND A NICE WARM UP INTO THE 70S AREA-WIDE. ABOUT THE ONLY THING THAT MIGHT WARRANT A COMPLAINT WOULD BE SOMEWHAT BREEZY WESTERLY WIND THIS AFTERNOON...ESPECIALLY NEAR/NORTH OF I-80. FOR THOSE WITH PARTICULAR INTEREST IN THE FIRE DANGER DETAILS TODAY...PLEASE REFER TO THE SEPARATE SECTION BELOW AS THIS TOPIC WILL NOT BE ADDRESSED ANY FURTHER IN THIS MAIN SHORT TERM SECTION. STARTING OFF WITH THE HERE AND NOW AS OF 08Z/3AM...THE ENTIRE CWA SITS UNDER ESSENTIALLY CLOUDLESS SKIES AS THE MASS OF CLOUDS FROM YESTERDAY HAS SUNK WELL OFF TO THE SOUTH. ALTHOUGH THE MAJORITY OF THE CWA IS TRULY FREE OF ALL WEATHER CONCERNS...AN AREA OF HIGHER DEWPOINTS AROUND 30 DEGREES RESIDING NEAR A SUBTLE TROUGH AXIS IN FAR SOUTHEAST COUNTIES SUCH AS THAYER/JEWELL/MITCHELL IS PROMOTING AT LEAST SOME PATCHY LIGHT FOG...WITH THE BELOIT AIRPORT EVEN SUGGESTING IT COULD BE PATCHY DENSE ESPECIALLY IN LOW-LYING AREAS. THANKS TO THE CLEAR SKIES AND A GENERALLY LIGHT/VARIABLE WIND REGIME WITH SUSTAINED SPEEDS LARGELY AROUND 5 MPH OR LESS...TEMPS THIS MORNING ARE DROPPING A BIT LOWER THAN ANTICIPATED IN MANY AREAS...AS IT NOW APPEARS THE MAJORITY OF THE CWA SHOULD BOTTOM OUT SOMEWHERE IN THE 25-32 RANGE. TURNING TO THE MID-UPPER LEVELS...THE LOCAL AREA REMAINS UNDER RATHER WEAK FLOW THANKS TO BEING WELL-REMOVED FROM BOTH THE NORTHERN AND SOUTHERN UPPER JET BRANCHES IN THIS LARGE-SCALE SPLIT FLOW REGIME...WITH THE NORTHERN BRANCH CENTERED MAINLY FROM CANADA INTO THE DAKOTAS...AND THE SOUTHERN BRANCH ORIENTED FROM MEXICO INTO THE SOUTHERN PLAINS AND EASTWARD. NOW LOOKING AHEAD FORECAST-WISE... EARLY THIS MORNING (ROUGHLY THROUGH 8 AM): AS MENTIONED ABOVE ABOUT THE ONLY CONCERN IS THE ONGOING POTENTIAL FOR AT LEAST PATCHY FOG MAINLY SOUTHEAST OF A HEBRON-OSBORNE LINE WHERE MOISTURE REMAINS HIGHER ALONG THE WEAK TROUGH AXIS. ALTHOUGH CERTAINLY NOT EXPECTING WIDESPREAD DENSE FOG ISSUES AT THIS POINT...PATCHY DENSE IS NOT OUT OF THE QUESTION AND MAY ADD THIS MENTION TO THE HAZARDOUS WEATHER OUTLOOK (HWOGID). FOR WHAT ITS WORTH...THE LATEST 07Z HRRR VISIBILITY PROG HAS CAUGHT ONTO THIS SMALL-SCALE AREA OF AT LEAST LIGHT FOG POTENTIAL. TODAY: ONCE ANY LINGERING MORNING FOG BURNS OFF IN THE SOUTHEAST...BY MOST FOLKS STANDARDS WE ARE LEFT WITH A PRETTY DARN PLEASANT DAY WITH A BIT OF BREEZE (ESPECIALLY NORTH) AND ESSENTIALLY WALL-TO-WALL SUNSHINE. IN THE MID-UPPER LEVELS...ESSENTIALLY NIL FORCING IN FAIRLY WEAK WEST-NORTHWEST FLOW AS THE LOCAL AREA REMAINS IN THE "QUIET ZONE" BETWEEN THE MAIN JET BRANCHES IN THE SPLIT REGIME. AT THE SURFACE...WEAK PRESSURE FALLS ASSOCIATED WITH A WEAK LOW PRESSURE SYSTEM SLIDING EAST-SOUTHEAST ACROSS THE DAKOTAS...ALONG WITH BROAD HIGH PRESSURE CENTERED TO THE SOUTH...WILL PROMOTE INCREASING WEST-SOUTHWEST BREEZES AS THE DAY WEARS ON. THESE BREEZES WILL PEAK IN INTENSITY THIS AFTERNOON THANKS TO DEEP DIURNAL MIXING PROGGED TO REACH UP TO AROUND 750 MILLIBARS PER GFS FORECAST SOUNDINGS. WITH THE STRONGEST CORRIDOR OF LOW-LEVEL WINDS FOCUSED NORTH OF I-80...THAT IS WHERE THE OVERALL-STRONGEST SUSTAINED SPEEDS OF AROUND 20 MPH WITH HIGHER GUSTS CLOSER TO 30 MPH WILL EXIST...WITH SPEEDS TAPERING OFF GRADUALLY WITH SOUTHWARD EXTENT...AND THUS KS ZONES ONLY EXPECTED TO SEE SUSTAINED SPEEDS AROUND 10 MPH. GIVEN THE DEEP MIXING ANTICIPATED...YET AGAIN AND AS HAS BEEN THE CASE ON SEVERAL DAYS THIS MONTH...VARIOUS SETS OF MODELS/GUIDANCE APPEAR TO BE TOO HIGH WITH AFTERNOON DEWPOINTS/RELATIVE HUMIDITY VALUES. ALTHOUGH MAY HAVE NOT GONE LOW ENOUGH...FOLLOWED CLOSEST TO GFS/RAP VALUES WITH DEWS AVERAGING WELL DOWN IN THE 20S CWA-WIDE FOR MOST OF THE DAY. TEMP-WISE...THIS SUNNY/DOWNSLOPE WESTERLY WIND REGIME SHOULD SQUEEZE OUT EVERY BIT OF WARMING POTENTIAL THAT IT CAN...AND NUDGED HIGH TEMPS OVER MUCH OF THE CWA UP ANOTHER 1-2 DEGREES...AIMING FOR A FAIRLY UNIFORM 73-75 RANGE MOST PLACES. BY VERY LATE THIS AFTERNOON (ESPECIALLY AFTER 6 PM)...THE AFTERNOON BREEZINESS SHOULD BE ON A FAIRLY STEADY DECLINE. THIS EVENING/TONIGHT: QUIET/ESSENTIALLY CLOUD-FREE WEATHER PERSISTS OVER THE LOCAL AREA IN WEAK QUASI-ZONAL FLOW ALOFT. AT THE SURFACE...HIGH PRESSURE WILL INCREASINGLY-BUILD SOUTHWARD INTO NEBRASKA AS THE NIGHT WEARS ON...EMANATING FROM A HIGH PRESSURE SYSTEM EXTENDING SOUTHWARD FROM THE CANADA/NORTH DAKOTA/MINNESOTA BORDER REGION. ALL THIS REALLY MEANS LOCALLY IS THAT WHILE THE EVENING HOURS WILL GENERALLY FEATURE SOUTH-SOUTHWEST BREEZES OF 5-10 MPH...THE POST-MIDNIGHT HOURS WILL BRING A WEAK COLD FRONT SOUTHWARD MAINLY INTO THE NORTHERN 1/2 OF THE CWA...MARKED BY A SWITCH TO FAIRLY LIGHT NORTH/NORTHEAST BREEZES. GIVEN THE CLEAR SKIES AND LIGHT BREEZES...WE MAY BE FACING ANOTHER NIGHT WITH TEMPS FALLING A BIT LOWER THAN CURRENT EXPECTATIONS...BUT GIVEN THE NOTICEABLY WARMER START TO THE NIGHT THIS TIME AROUND...GENERALLY EXPECT LOWS TO HOLD UP ABOUT 5-8 DEGREES WARMER THAN THIS MORNING. AS A RESULT...HAVE LOWS AIMED 35-39 ACROSS MOST OF THE CWA...AND COLDER LOW 30S MOST FAVORED IN THE USUAL VALLEY/GREELEY/DAWSON COUNTY AREAS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 359 AM CDT FRI MAR 20 2015 ACTUALLY A DECENT AMOUNT OF INTERESTING WEATHER IN THE EXTENDED PERIOD. IN GENERAL...TEMPERATURES REMAIN WELL ABOVE NORMAL THROUGH TUESDAY...AND THEN START TO COOL BACK TO NEAR SEASONAL NORMALS WEDNESDAY AND THURSDAY. PRECIPITATION CHANCES CENTERED ON MONDAY NIGHT. THOUGH SPRING STARTS TODAY AT 2245Z...SATURDAY WILL BE THE FIRST FULL DAY OF SPRING AND IT WILL BE A NICE ONE. HIGHS IN THE 70S AND REASONABLY LIGHT SOUTH WINDS. LOW LEVEL MOISTURE STARTS TO SNEAK UP INTO THE AREA BY SUNDAY MORNING...WITH DEWPOINTS WELL INTO THE 40S EXPECTED OVER PARTS OF THE AREA SUNDAY. ALL THIS IS AHEAD OF A WEAK SURFACE FRONT. THE FRONT WILL BE A FOCUS FOR LOW LEVEL CONVERGENCE...AND THE INCREASING MOISTURE RESULTS IN SOME 500+ CAPE VALUES BY AFTERNOON. MODEL TRENDS HAVE SLID THE CONVECTIVE POTENTIAL TO THE EAST...OR MAINLY EAST OF HIGHWAY 81. THERE IS GOOD AGREEMENT WITH THE MODELS THIS EVENT WILL BE GET GOING FURTHER EAST AND LATER IN THE EVENING. FOR THAT REASON HAVE TRIMMED THUNDERSTORM CHANCES BACK AND HUGGED THE EASTERN EDGE OF THE FORECAST AREA. THIS WINDOW OF OPPORTUNITY LOOKS PRETTY SMALL BOTH TIMING AND COVERAGE WISE AT THIS TIME. ATTENTION TURNS TO MONDAY AND TUESDAY...WHEN A WEAK SHORT WAVE WILL RIDE OVER AN UPPER LEVEL RIDGE. WARM ADVECTION WILL ALSO KICK IN AND THERE IS SOMEWHAT IMPROVING CHANCES FOR SHOWERS AND ISOLATED THUNDERSTORMS MOVING INTO FROM THE SOUTH MONDAY AND SPREADING OVER MOST OF THE AREA MONDAY NIGHT AND THE FIRST HALF OF THE DAY TUESDAY. MID LEVEL LAPSE RATES ARE ACTUALLY PRETTY UNSTABLE MONDAY NIGHT AS LOW LEVEL MOISTURE CREEPS BACK INTO THE AREA. SOME WEAK ELEVATED CAPE ALSO SUPPORTS AT LEAST ISOLATED THUNDERSTORMS. STILL A FEW DAYS AWAY...BUT THERE IS AT LEAST SOME CHANCE OF MEASURABLE RAINFALL FOR MOST AREAS... ESPECIALLY MONDAY NIGHT AND EARLY TUESDAY. SIGNS NOW POINT TOWARD AMOUNTS IN THE 0.15 TO 0.35 RANGE...BUT IT IS EARLY. ALL OF THE PRECIPITATION LIFTS NORTHEAST OF THE REGION BY ABOUT MIDDAY TUESDAY AS UPPER LEVEL LOW PRESSURE DEEPENS TO OUR NORTH IN THE DAKOTAS. SUCH A LOW POSITION HAS SOME POTENTIAL TO SWEEP SOME DRY AIR ACROSS THE FORECAST AREA TUESDAY AFTERNOON ABOARD WESTERLY WINDS. SO DESPITE SOME RAINFALL POTENTIALLY EARLY IN THE DAY...THE RAPID DRYING MAY BE A FIRE WEATHER ISSUE LATE THE AFTERNOON FOR SOME AREAS. SEE THE FIRE WEATHER DISCUSSION FOR MORE INFORMATION. TUESDAY LOOKS LIKE THE LAST WELL ABOVE NORMAL DAY FOR TEMPERATURES AS COOLER AIR INVADES THE REGION BY WEDNESDAY AND LINGERS INTO THURSDAY. GOOD NEWS IS THE COOLER TEMPS ARE REALLY ONLY ABOUT NORMAL AT THE COOLEST. PEERING AHEAD A BIT FURTHER...WHATEVER RAIN WE MAY GET EARLY NEXT WEEK COULD BE PRETTY HANDY...AS THE LIKELIHOOD OF ANY OTHER SUBSTANTIAL RAINFALL PRIOR TO THE END OF THE MONTH LOOKS IFFY AT BEST. TEMPERATURES MAY CLIMB BACK ABOVE NORMAL AGAIN BY NEXT WEEKEND. && .AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 651 AM CDT FRI MAR 20 2015 WITH ESSENTIALLY NO SKY COVER WHATSOEVER ANTICIPATED...CONFIDENCE IS QUITE HIGH IN CONTINUED VFR CEILING/VISIBILITY. THAT LEAVES WIND AS THE MAIN ISSUE...ESPECIALLY A PERIOD OF MODEST GUSTINESS THIS AFTERNOON. STARTING OFF THIS MORNING...VERY LIGHT WESTERLY BREEZES WILL GRADUALLY PICK UP WITH TIME...BEFORE PEAKING IN INTENSITY MAINLY DURING THE 18Z-23Z TIME FRAME THIS AFTERNOON...DURING WHICH GUST POTENTIAL WILL BE UP AROUND 22KT. BY SUNSET BREEZES WILL SUBSIDE TO SPEEDS AT/BELOW 10KT...AND WILL REMAIN FAIRLY LIGHT THROUGHOUT THE NIGHT ALTHOUGH A WEAK COLD FRONT WILL RESULT IN A DIRECTIONAL CHANGE TRANSITION FROM SOUTHERLY TO VARIABLE/NORTHERLY. && .FIRE WEATHER... ISSUED AT 359 AM CDT FRI MAR 20 2015 THIS AFTERNOON/EARLY EVENING: NOT SURPRISING GIVEN TRENDS OVER THE PAST FEW DAYS...TODAY IS NOW OFFICIALLY CONSIDERED A CRITICAL FIRE DANGER DAY FOR MOST COUNTIES ALONG/NORTH OF THE INTERSTATE 80 CORRIDOR...AND HAVE COORDINATED WITH NEIGHBORING OFFICES LBF/OAX ON AN UPGRADE/EXPANSION OF THE PREVIOUS FIRE WEATHER WATCH TO A RED FLAG WARNING VALID FROM 18Z- 01Z/1PM-8PM. JUST AS A QUICK REVIEW FOR THOSE WHO MIGHT BE UNFAMILIAR WITH FIRE WEATHER CRITERIA: "CRITICAL" FIRE WEATHER IN OUR CWA IS DEFINED AS THE 3+ HOUR OVERLAP OF RELATIVE HUMIDITY (RH) OF 20 PERCENT-OR-LOWER AND SUSTAINED WINDS/GUSTS OF 20 MPH/25 MPH. "NEAR-CRITICAL" IS DEFINED AS THE OVERLAP OF 25 PERCENT-OR- LOWER RH AND SUSTAINED WINDS GUSTS OF 15 MPH/20 MPH (IN THE PRESENCE OF DRY VEGETATION OF COURSE). WITHIN THE WARNING AREA...CONFIDENCE HAS INCREASED IN REACHING CRITICAL CRITERIA...WITH RH VALUES EXPECTED TO SOLIDLY CRASH INTO THE 14-20 PERCENT RANGE FOR SEVERAL HOURS. WIND-WISE...ALTHOUGH SOME PLACES IN THE WARNING MAY NOT SEE WIDESPREAD 20+ MPH SUSTAINED WESTERLY SPEEDS ALL AFTERNOON...THERE SHOULD BE A GREATER LIKELIHOOD OF REALIZING SEMI-FREQUENT 25+ MPH GUSTS GIVEN DEEP MIXING...ESPECIALLY NORTH OF HIGHWAY 92. OF COURSE...IT IS ALWAYS IMPORTANT TO REMEMBER THAT EVEN OUTSIDE THE OFFICIAL RED FLAG AREA...AT LEAST NEAR-CRITICAL FIRE DANGER WILL CERTAINLY EXIST...ESPECIALLY FOR COUNTIES BETWEEN I-80 AND THE STATE LINE WHERE GUST POTENTIAL TO 20+ MPH SHOULD EXIST. ALTHOUGH NOT "TOTALLY SAFE" BY ANY MEANS...NORTH CENTRAL KANSAS ZONES SHOULD BE UNDER THE LEAST-OVERALL THREAT THIS AFTERNOON GIVEN THAT EVEN GUSTS SHOULD FALL SHORT OF 20 MPH. ON ONE LAST NOTE...THE WARNING END TIME OF 8PM IS PROBABLY PLENTY GENEROUS GIVEN THAT WIND SPEEDS SHOULD REALLY SLACKEN CONSIDERABLY BY 7PM IF NOT SOONER...BUT GIVEN HOW LOW RH VALUES SHOULD DROP...WOULD RATHER GIVE LATER SHIFTS A CHANCE TO CANCEL A BIT EARLY THAN HAVE TO EXTEND. BEYOND TODAY: DESPITE THE FACT THERE ARE AT LEAST SMALL CHANCES FOR PRECIPITATION PEPPERED IN THE LATE SUNDAY THROUGH WEDNESDAY TIMEFRAME...THERE COULD BE A COUPLE OF PERIODS OF HEIGHTENED FIRE WEATHER CONDITIONS. SATURDAY WILL SEE SOME PRETTY LOW RELATIVE HUMIDITY VALUES IN THE SOUTHWEST...BUT THE WIND SHOULD REMAIN BELOW 15 MPH. ANOTHER MAY BE SUNDAY AFTERNOON ACROSS ABOUT THE WESTERN HALF OF THE FORECAST AREA. DRIER AIR WILL FILTER IN AS A NORTHWEST WIND TAKES HOLD IN A POST FRONT REGIME. TEMPS WILL BE WELL ABOVE NORMAL AGAIN. WIND SPEEDS ARE A BIT MARGINAL AND IT WILL BE TOTALLY BASED ON TIMING. SIMILAR DEAL ON TUESDAY BUT THIS TIME STRONG UPPER LEVEL LOW PRESSURE OVER THE DAKOTAS WILL HELP CREATE A DOWNSLOPE WESTERLY FLOW BY AFTERNOON...AGAIN OVER THE WESTERN HALF OF THE FORECAST. IT DOESN/T LOOK AS WARM BUT SURFACE DEWPOINTS COULD REALLY TANK...POSSIBLY WELL BELOW THE ONGOING FORECAST. AGAIN... TIMING IS THE KEY AND THIS PERIOD SHOULD BE CONSIDERED ONE TO WATCH AS THE TIME APPROACHES. && .GID WATCHES/WARNINGS/ADVISORIES... NE...RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING FOR NEZ039>041-046>049-060>063. KS...NONE. && $$ UPDATE...PFANNKUCH SHORT TERM...PFANNKUCH LONG TERM...MORITZ AVIATION...PFANNKUCH FIRE WEATHER...PFANNKUCH/MORITZ
AREA FORECAST DISCUSSION
NWS HASTINGS NE
359 AM CDT FRI MAR 20 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 359 AM CDT FRI MAR 20 2015 IF NOT FOR THE NOW-CRITICAL FIRE DANGER CONCERNS MAINLY NORTH OF THE INTERSTATE 80 CORRIDOR THIS AFTERNOON...THIS WOULD ACTUALLY BE A FAIRLY STRAIGHTFORWARD 24 HOURS WITH ESSENTIALLY CLOUD-FREE SKIES...EFFECTIVELY ZERO RISK OF PRECIP...AND A NICE WARM UP INTO THE 70S AREA-WIDE. ABOUT THE ONLY THING THAT MIGHT WARRANT A COMPLAINT WOULD BE SOMEWHAT BREEZY WESTERLY WIND THIS AFTERNOON...ESPECIALLY NEAR/NORTH OF I-80. FOR THOSE WITH PARTICULAR INTEREST IN THE FIRE DANGER DETAILS TODAY...PLEASE REFER TO THE SEPARATE SECTION BELOW AS THIS TOPIC WILL NOT BE ADDRESSED ANY FURTHER IN THIS MAIN SHORT TERM SECTION. STARTING OFF WITH THE HERE AND NOW AS OF 08Z/3AM...THE ENTIRE CWA SITS UNDER ESSENTIALLY CLOUDLESS SKIES AS THE MASS OF CLOUDS FROM YESTERDAY HAS SUNK WELL OFF TO THE SOUTH. ALTHOUGH THE MAJORITY OF THE CWA IS TRULY FREE OF ALL WEATHER CONCERNS...AN AREA OF HIGHER DEWPOINTS AROUND 30 DEGREES RESIDING NEAR A SUBTLE TROUGH AXIS IN FAR SOUTHEAST COUNTIES SUCH AS THAYER/JEWELL/MITCHELL IS PROMOTING AT LEAST SOME PATCHY LIGHT FOG...WITH THE BELOIT AIRPORT EVEN SUGGESTING IT COULD BE PATCHY DENSE ESPECIALLY IN LOW-LYING AREAS. THANKS TO THE CLEAR SKIES AND A GENERALLY LIGHT/VARIABLE WIND REGIME WITH SUSTAINED SPEEDS LARGELY AROUND 5 MPH OR LESS...TEMPS THIS MORNING ARE DROPPING A BIT LOWER THAN ANTICIPATED IN MANY AREAS...AS IT NOW APPEARS THE MAJORITY OF THE CWA SHOULD BOTTOM OUT SOMEWHERE IN THE 25-32 RANGE. TURNING TO THE MID-UPPER LEVELS...THE LOCAL AREA REMAINS UNDER RATHER WEAK FLOW THANKS TO BEING WELL-REMOVED FROM BOTH THE NORTHERN AND SOUTHERN UPPER JET BRANCHES IN THIS LARGE-SCALE SPLIT FLOW REGIME...WITH THE NORTHERN BRANCH CENTERED MAINLY FROM CANADA INTO THE DAKOTAS...AND THE SOUTHERN BRANCH ORIENTED FROM MEXICO INTO THE SOUTHERN PLAINS AND EASTWARD. NOW LOOKING AHEAD FORECAST-WISE... EARLY THIS MORNING (ROUGHLY THROUGH 8 AM): AS MENTIONED ABOVE ABOUT THE ONLY CONCERN IS THE ONGOING POTENTIAL FOR AT LEAST PATCHY FOG MAINLY SOUTHEAST OF A HEBRON-OSBORNE LINE WHERE MOISTURE REMAINS HIGHER ALONG THE WEAK TROUGH AXIS. ALTHOUGH CERTAINLY NOT EXPECTING WIDESPREAD DENSE FOG ISSUES AT THIS POINT...PATCHY DENSE IS NOT OUT OF THE QUESTION AND MAY ADD THIS MENTION TO THE HAZARDOUS WEATHER OUTLOOK (HWOGID). FOR WHAT ITS WORTH...THE LATEST 07Z HRRR VISIBILITY PROG HAS CAUGHT ONTO THIS SMALL-SCALE AREA OF AT LEAST LIGHT FOG POTENTIAL. TODAY: ONCE ANY LINGERING MORNING FOG BURNS OFF IN THE SOUTHEAST...BY MOST FOLKS STANDARDS WE ARE LEFT WITH A PRETTY DARN PLEASANT DAY WITH A BIT OF BREEZE (ESPECIALLY NORTH) AND ESSENTIALLY WALL-TO-WALL SUNSHINE. IN THE MID-UPPER LEVELS...ESSENTIALLY NIL FORCING IN FAIRLY WEAK WEST-NORTHWEST FLOW AS THE LOCAL AREA REMAINS IN THE "QUIET ZONE" BETWEEN THE MAIN JET BRANCHES IN THE SPLIT REGIME. AT THE SURFACE...WEAK PRESSURE FALLS ASSOCIATED WITH A WEAK LOW PRESSURE SYSTEM SLIDING EAST-SOUTHEAST ACROSS THE DAKOTAS...ALONG WITH BROAD HIGH PRESSURE CENTERED TO THE SOUTH...WILL PROMOTE INCREASING WEST-SOUTHWEST BREEZES AS THE DAY WEARS ON. THESE BREEZES WILL PEAK IN INTENSITY THIS AFTERNOON THANKS TO DEEP DIURNAL MIXING PROGGED TO REACH UP TO AROUND 750 MILLIBARS PER GFS FORECAST SOUNDINGS. WITH THE STRONGEST CORRIDOR OF LOW-LEVEL WINDS FOCUSED NORTH OF I-80...THAT IS WHERE THE OVERALL-STRONGEST SUSTAINED SPEEDS OF AROUND 20 MPH WITH HIGHER GUSTS CLOSER TO 30 MPH WILL EXIST...WITH SPEEDS TAPERING OFF GRADUALLY WITH SOUTHWARD EXTENT...AND THUS KS ZONES ONLY EXPECTED TO SEE SUSTAINED SPEEDS AROUND 10 MPH. GIVEN THE DEEP MIXING ANTICIPATED...YET AGAIN AND AS HAS BEEN THE CASE ON SEVERAL DAYS THIS MONTH...VARIOUS SETS OF MODELS/GUIDANCE APPEAR TO BE TOO HIGH WITH AFTERNOON DEWPOINTS/RELATIVE HUMIDITY VALUES. ALTHOUGH MAY HAVE NOT GONE LOW ENOUGH...FOLLOWED CLOSEST TO GFS/RAP VALUES WITH DEWS AVERAGING WELL DOWN IN THE 20S CWA-WIDE FOR MOST OF THE DAY. TEMP-WISE...THIS SUNNY/DOWNSLOPE WESTERLY WIND REGIME SHOULD SQUEEZE OUT EVERY BIT OF WARMING POTENTIAL THAT IT CAN...AND NUDGED HIGH TEMPS OVER MUCH OF THE CWA UP ANOTHER 1-2 DEGREES...AIMING FOR A FAIRLY UNIFORM 73-75 RANGE MOST PLACES. BY VERY LATE THIS AFTERNOON (ESPECIALLY AFTER 6 PM)...THE AFTERNOON BREEZINESS SHOULD BE ON A FAIRLY STEADY DECLINE. THIS EVENING/TONIGHT: QUIET/ESSENTIALLY CLOUD-FREE WEATHER PERSISTS OVER THE LOCAL AREA IN WEAK QUASI-ZONAL FLOW ALOFT. AT THE SURFACE...HIGH PRESSURE WILL INCREASINGLY-BUILD SOUTHWARD INTO NEBRASKA AS THE NIGHT WEARS ON...EMANATING FROM A HIGH PRESSURE SYSTEM EXTENDING SOUTHWARD FROM THE CANADA/NORTH DAKOTA/MINNESOTA BORDER REGION. ALL THIS REALLY MEANS LOCALLY IS THAT WHILE THE EVENING HOURS WILL GENERALLY FEATURE SOUTH-SOUTHWEST BREEZES OF 5-10 MPH...THE POST-MIDNIGHT HOURS WILL BRING A WEAK COLD FRONT SOUTHWARD MAINLY INTO THE NORTHERN 1/2 OF THE CWA...MARKED BY A SWITCH TO FAIRLY LIGHT NORTH/NORTHEAST BREEZES. GIVEN THE CLEAR SKIES AND LIGHT BREEZES...WE MAY BE FACING ANOTHER NIGHT WITH TEMPS FALLING A BIT LOWER THAN CURRENT EXPECTATIONS...BUT GIVEN THE NOTICEABLY WARMER START TO THE NIGHT THIS TIME AROUND...GENERALLY EXPECT LOWS TO HOLD UP ABOUT 5-8 DEGREES WARMER THAN THIS MORNING. AS A RESULT...HAVE LOWS AIMED 35-39 ACROSS MOST OF THE CWA...AND COLDER LOW 30S MOST FAVORED IN THE USUAL VALLEY/GREELEY/DAWSON COUNTY AREAS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 359 AM CDT FRI MAR 20 2015 ACTUALLY A DECENT AMOUNT OF INTERESTING WEATHER IN THE EXTENDED PERIOD. IN GENERAL...TEMPERATURES REMAIN WELL ABOVE NORMAL THROUGH TUESDAY...AND THEN START TO COOL BACK TO NEAR SEASONAL NORMALS WEDNESDAY AND THURSDAY. PRECIPITATION CHANCES CENTERED ON MONDAY NIGHT. THOUGH SPRING STARTS TODAY AT 2245Z...SATURDAY WILL BE THE FIRST FULL DAY OF SPRING AND IT WILL BE A NICE ONE. HIGHS IN THE 70S AND REASONABLY LIGHT SOUTH WINDS. LOW LEVEL MOISTURE STARTS TO SNEAK UP INTO THE AREA BY SUNDAY MORNING...WITH DEWPOINTS WELL INTO THE 40S EXPECTED OVER PARTS OF THE AREA SUNDAY. ALL THIS IS AHEAD OF A WEAK SURFACE FRONT. THE FRONT WILL BE A FOCUS FOR LOW LEVEL CONVERGENCE...AND THE INCREASING MOISTURE RESULTS IN SOME 500+ CAPE VALUES BY AFTERNOON. MODEL TRENDS HAVE SLID THE CONVECTIVE POTENTIAL TO THE EAST...OR MAINLY EAST OF HIGHWAY 81. THERE IS GOOD AGREEMENT WITH THE MODELS THIS EVENT WILL BE GET GOING FURTHER EAST AND LATER IN THE EVENING. FOR THAT REASON HAVE TRIMMED THUNDERSTORM CHANCES BACK AND HUGGED THE EASTERN EDGE OF THE FORECAST AREA. THIS WINDOW OF OPPORTUNITY LOOKS PRETTY SMALL BOTH TIMING AND COVERAGE WISE AT THIS TIME. ATTENTION TURNS TO MONDAY AND TUESDAY...WHEN A WEAK SHORT WAVE WILL RIDE OVER AN UPPER LEVEL RIDGE. WARM ADVECTION WILL ALSO KICK IN AND THERE IS SOMEWHAT IMPROVING CHANCES FOR SHOWERS AND ISOLATED THUNDERSTORMS MOVING INTO FROM THE SOUTH MONDAY AND SPREADING OVER MOST OF THE AREA MONDAY NIGHT AND THE FIRST HALF OF THE DAY TUESDAY. MID LEVEL LAPSE RATES ARE ACTUALLY PRETTY UNSTABLE MONDAY NIGHT AS LOW LEVEL MOISTURE CREEPS BACK INTO THE AREA. SOME WEAK ELEVATED CAPE ALSO SUPPORTS AT LEAST ISOLATED THUNDERSTORMS. STILL A FEW DAYS AWAY...BUT THERE IS AT LEAST SOME CHANCE OF MEASURABLE RAINFALL FOR MOST AREAS... ESPECIALLY MONDAY NIGHT AND EARLY TUESDAY. SIGNS NOW POINT TOWARD AMOUNTS IN THE 0.15 TO 0.35 RANGE...BUT IT IS EARLY. ALL OF THE PRECIPITATION LIFTS NORTHEAST OF THE REGION BY ABOUT MIDDAY TUESDAY AS UPPER LEVEL LOW PRESSURE DEEPENS TO OUR NORTH IN THE DAKOTAS. SUCH A LOW POSITION HAS SOME POTENTIAL TO SWEEP SOME DRY AIR ACROSS THE FORECAST AREA TUESDAY AFTERNOON ABOARD WESTERLY WINDS. SO DESPITE SOME RAINFALL POTENTIALLY EARLY IN THE DAY...THE RAPID DRYING MAY BE A FIRE WEATHER ISSUE LATE THE AFTERNOON FOR SOME AREAS. SEE THE FIRE WEATHER DISCUSSION FOR MORE INFORMATION. TUESDAY LOOKS LIKE THE LAST WELL ABOVE NORMAL DAY FOR TEMPERATURES AS COOLER AIR INVADES THE REGION BY WEDNESDAY AND LINGERS INTO THURSDAY. GOOD NEWS IS THE COOLER TEMPS ARE REALLY ONLY ABOUT NORMAL AT THE COOLEST. PEERING AHEAD A BIT FURTHER...WHATEVER RAIN WE MAY GET EARLY NEXT WEEK COULD BE PRETTY HANDY...AS THE LIKELIHOOD OF ANY OTHER SUBSTANTIAL RAINFALL PRIOR TO THE END OF THE MONTH LOOKS IFFY AT BEST. TEMPERATURES MAY CLIMB BACK ABOVE NORMAL AGAIN BY NEXT WEEKEND. && .AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1221 AM CDT FRI MAR 20 2015 WITH ESSENTIALLY NO SKY COVER WHATSOEVER ANTICIPATED...CONFIDENCE IS QUITE HIGH IN CONTINUED VFR CEILING/VISIBILITY. THAT LEAVES WIND AS THE MAIN ISSUE...ESPECIALLY A PERIOD OF MODEST GUSTINESS DURING THE AFTERNOON HOURS. STARTING OFF EARLY THIS MORNING...VERY LIGHT/GENERALLY WESTERLY BREEZE WILL PREVAIL. AFTER SUNRISE...WEST-SOUTHWEST SPEEDS WILL START TO PICK UP A BIT...WITH GUST POTENTIAL TO AROUND 22KT THEN PEAKING DURING THE 18Z-23Z TIME FRAME BEFORE SUBSIDING TO AT/BELOW 10KT THROUGH THE REMAINDER OF FRIDAY EVENING. && .FIRE WEATHER... ISSUED AT 359 AM CDT FRI MAR 20 2015 THIS AFTERNOON/EARLY EVENING: NOT SURPRISING GIVEN TRENDS OVER THE PAST FEW DAYS...TODAY IS NOW OFFICIALLY CONSIDERED A CRITICAL FIRE DANGER DAY FOR MOST COUNTIES ALONG/NORTH OF THE INTERSTATE 80 CORRIDOR...AND HAVE COORDINATED WITH NEIGHBORING OFFICES LBF/OAX ON AN UPGRADE/EXPANSION OF THE PREVIOUS FIRE WEATHER WATCH TO A RED FLAG WARNING VALID FROM 18Z- 01Z/1PM-8PM. JUST AS A QUICK REVIEW FOR THOSE WHO MIGHT BE UNFAMILIAR WITH FIRE WEATHER CRITERIA: "CRITICAL" FIRE WEATHER IN OUR CWA IS DEFINED AS THE 3+ HOUR OVERLAP OF RELATIVE HUMIDITY (RH) OF 20 PERCENT-OR-LOWER AND SUSTAINED WINDS/GUSTS OF 20 MPH/25 MPH. "NEAR-CRITICAL" IS DEFINED AS THE OVERLAP OF 25 PERCENT-OR- LOWER RH AND SUSTAINED WINDS GUSTS OF 15 MPH/20 MPH (IN THE PRESENCE OF DRY VEGETATION OF COURSE). WITHIN THE WARNING AREA...CONFIDENCE HAS INCREASED IN REACHING CRITICAL CRITERIA...WITH RH VALUES EXPECTED TO SOLIDLY CRASH INTO THE 14-20 PERCENT RANGE FOR SEVERAL HOURS. WIND-WISE...ALTHOUGH SOME PLACES IN THE WARNING MAY NOT SEE WIDESPREAD 20+ MPH SUSTAINED WESTERLY SPEEDS ALL AFTERNOON...THERE SHOULD BE A GREATER LIKELIHOOD OF REALIZING SEMI-FREQUENT 25+ MPH GUSTS GIVEN DEEP MIXING...ESPECIALLY NORTH OF HIGHWAY 92. OF COURSE...IT IS ALWAYS IMPORTANT TO REMEMBER THAT EVEN OUTSIDE THE OFFICIAL RED FLAG AREA...AT LEAST NEAR-CRITICAL FIRE DANGER WILL CERTAINLY EXIST...ESPECIALLY FOR COUNTIES BETWEEN I-80 AND THE STATE LINE WHERE GUST POTENTIAL TO 20+ MPH SHOULD EXIST. ALTHOUGH NOT "TOTALLY SAFE" BY ANY MEANS...NORTH CENTRAL KANSAS ZONES SHOULD BE UNDER THE LEAST-OVERALL THREAT THIS AFTERNOON GIVEN THAT EVEN GUSTS SHOULD FALL SHORT OF 20 MPH. ON ONE LAST NOTE...THE WARNING END TIME OF 8PM IS PROBABLY PLENTY GENEROUS GIVEN THAT WIND SPEEDS SHOULD REALLY SLACKEN CONSIDERABLY BY 7PM IF NOT SOONER...BUT GIVEN HOW LOW RH VALUES SHOULD DROP...WOULD RATHER GIVE LATER SHIFTS A CHANCE TO CANCEL A BIT EARLY THAN HAVE TO EXTEND. BEYOND TODAY: DESPITE THE FACT THERE ARE AT LEAST SMALL CHANCES FOR PRECIPITATION PEPPERED IN THE LATE SUNDAY THROUGH WEDNESDAY TIMEFRAME...THERE COULD BE A COUPLE OF PERIODS OF HEIGHTENED FIRE WEATHER CONDITIONS. SATURDAY WILL SEE SOME PRETTY LOW RELATIVE HUMIDITY VALUES IN THE SOUTHWEST...BUT THE WIND SHOULD REMAIN BELOW 15 MPH. ANOTHER MAY BE SUNDAY AFTERNOON ACROSS ABOUT THE WESTERN HALF OF THE FORECAST AREA. DRIER AIR WILL FILTER IN AS A NORTHWEST WIND TAKES HOLD IN A POST FRONT REGIME. TEMPS WILL BE WELL ABOVE NORMAL AGAIN. WIND SPEEDS ARE A BIT MARGINAL AND IT WILL BE TOTALLY BASED ON TIMING. SIMILAR DEAL ON TUESDAY BUT THIS TIME STRONG UPPER LEVEL LOW PRESSURE OVER THE DAKOTAS WILL HELP CREATE A DOWNSLOPE WESTERLY FLOW BY AFTERNOON...AGAIN OVER THE WESTERN HALF OF THE FORECAST. IT DOESN/T LOOK AS WARM BUT SURFACE DEWPOINTS COULD REALLY TANK...POSSIBLY WELL BELOW THE ONGOING FORECAST. AGAIN... TIMING IS THE KEY AND THIS PERIOD SHOULD BE CONSIDERED ONE TO WATCH AS THE TIME APPROACHES. && .GID WATCHES/WARNINGS/ADVISORIES... NE...RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING FOR NEZ039>041-046>049-060>063. KS...NONE. && $$ SHORT TERM...PFANNKUCH LONG TERM...MORITZ AVIATION...PFANNKUCH FIRE WEATHER...PFANNKUCH/MORITZ
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
352 AM CDT FRI MAR 20 2015 .SYNOPSIS... ISSUED AT 351 AM CDT FRI MAR 20 2015 CUTOFF LOW OVER THE BAJA...RIDGING INTO THE PACIFIC NORTHWEST AND THE SOUTHEAST CONUS WITH AN UPPER HIGH OVER CUBA. TROUGH FROM HUDSON BAY LOW INTO THE OHIO VALLEY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 351 AM CDT FRI MAR 20 2015 MODELS IN FAIR AGREEMENT IN NEAR TERM. HAVE GOOD CONFIDENCE IN THE FORECAST. MAIN CONCERNS WILL BE FIRE WEATHER CONDITIONS OVER WESTERN NEBRASKA TODAY...SEE DISCUSSION BELOW. SPLIT FLOW REGIME ALOFT WITH STRONG SUBSIDENCE OVER WESTERN NEBRASKA TODAY. CLEAR SKIES FULL SUN AND GUSTY SOUTHWEST FLOW. HAVE UPPED TEMPERATURES BY 3 TO 4 DEGREES ABOVE GUIDANCE WITH STRONG WEST TO SOUTHWEST FLOW. LOWERED DEWPOINTS INTO THE TEENS OVER MUCH OF THE SANDHILLS AND SOUTHWEST NEBRASKA FOLLOWING RUC FORECAST. DEWPOINTS OVER THE PANHANDLE IN THE TEENS EARLY THIS MORNING. UNDER CLEAR SKIES TEMPERATURES WILL REMAIN IN THE 30S OVER NIGHT WITH SOME LOWER READINGS ALONG RIVER VALLEYS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 351 AM CDT FRI MAR 20 2015 ACTIVE PATTERN FOR THE LONG TERM PERIOD. MAIN FOCUS WILL BE ON AND OFF FIRE CONCERNS AND MODEL DIFFERENCES WITH A FEW SHOTS AT RAINFALL/THUNDER...YES PRECIP...NEXT WEEK...ALBEIT NOT GREAT SHOTS. SATURDAY A STALLING COOL FRONT WILL BEGIN TO PUSH BACK TO THE NORTHEAST AS A WARM FRONT. QUESTION IS HOW FAR IT MAKES IT INTO N CENTRAL NEB AS TO TEMPS THERE. TO THE SOUTHWEST OF THE FRONT...850 MB TEMPS SOAR BACK TO 14C TO 18C. GUIDANCE RETURNS TEMPS INTO THE MID TO UPPER 70S. WITH LITTLE CLOUD COVER EXPECTED...HAVE SIDED WITH THE WARMER VALUES. TO THE NORTHEAST OF THE FRONT...STILL MILD AIR FOR FEBRUARY WITH HIGHS IN THE 60S. WINDS TO THE SOUTHWEST OF THE FRONT WILL BE FAIRLY LIGHT...15 MPH OR LESS...SO WHILE RH VALUES WILL BE AT OR BELOW CRITICAL LEVELS NO HEADLINE AT THIS TIME. SUNDAY A SFC LOW AND TRAILING COLD FRONT WILL SLIDE SE ACROSS THE AREA. TIMING STILL IN QUESTION WITH THE GFS FASTER...BRINGING COLD AIR CLOSER TO THE CWA....WHICH MAKES FOR A LOW CONFIDENCE TEMP FORECAST. MIXING ALONG THE FRONT SHOULD HELP TO PUSH TEMPS UP SO STILL WENT WITH 60S AND 70S AGAIN. MODELS IN GENERALLY HAVE INCREASE THE ARRIVAL OF THE FRONT...WHICH HAS RESULTED IN THE BETTER MOISTURE/LIFT FOCUSING MAINLY TO THE NORTH AND EAST OF THE CWA...SO TRIMMED INHERITED POPS. MONDAY THROUGH WEDNESDAY A SERIES OF DISTURBANCES WILL PUSH ACROSS THE PLAINS...HOWEVER MODELS CONTINUE TO STRUGGLE WITH THE TRACK AND TIMING. THE FIRST WAVE ARRIVES MONDAY MORNING. DRY SLOT ACROSS SW WITH THE REST OF THE AREA WITH LOW POPS. SOUTHERLY WINDS WILL BE INCREASING MOISTURE...HOWEVER WOULD NOT BE SURPRISED MOST OF THE PRECIP IS JUST LIGHT RAIN OR SPRINKLES. MONDAY NIGHT THE GFS FAVORS AN ELEVATED TROUGH TO LIFT NE ACROSS THE AREA. A NEG ELEVATED LIFTED INDEX AND MARGINAL MOISTURE COULD RESULT IN SOME OVERNIGHT THUNDER. LINGERING T CHANCE FOR TUESDAY AS THE ACTIVITY LIFTS NE OF THE AREA. WEDNESDAY A STRONGER LOW SLIDES ACROSS THE NORTHERN/CENTRAL PLAINS...WITH A TRAILING COLD FRONT. SOME ARCTIC AIR FILLS IN BEHIND THE FRONT AS 850 MB TEMPS FALL BELOW ZERO. LACK OF MOISTURE IS STILL A CONCERN WITH PASSAGE...HOWEVER THE COOLER TEMPS COULD RESULT IN RAIN MAYBE MIXING WITH SNOW WED NIGHT IF IT HAS NOT EXITED YET. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1140 PM CDT THU MAR 19 2015 VFR IS EXPECTED ALL AREAS OVERNIGHT THROUGH FRIDAY EVENING. SFC LOW PRESSURE ACROSS SERN ALBERTA WILL CIRCULATE THROUGH THE DAKOTAS FRIDAY AND BE LOCATED OVER MN BY FRIDAY EVENING. FEW CLOUDS ARE EXPECTED ACROSS WRN AND NCNTL NEBRASKA DURING THIS TIME. && .FIRE WEATHER... ISSUED AT 351 AM CDT FRI MAR 20 2015 CRITICAL FIRE WEATHER DAY OVER WESTERN NEBRASKA WHERE MOISTURE HAS BEEN SPARSE OVER THE LAST MONTH. WEST TO SOUTHWEST FLOW TODAY WITH DEW POINTS FALLING INTO THE TEENS AND SURFACE TEMPERATURES RISING INTO THE MID 70S THIS AFTERNOON. NORTHEAST ZONES WILL BE MORE SUSCEPTIBLE WITH STRONGER WIND FORECAST AS COOL FRONT MOVES SOUTH OUT OF SOUTH DAKOTA THIS EVENING. WINDS SOMEWHAT MARGINAL OVER THE SOUTHEAST NEBRASKA PANHANDLE AND SOUTHWEST NEBRASKA BUT HAVE INCLUDED DUE TO LOW RH AND VERY DRY CONDITIONS. && .LBF WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ THIS AFTERNOON TO 8 PM CDT /7 PM MDT/ THIS EVENING FOR NEZ204-206-208>210-219. && $$ SYNOPSIS...POWER SHORT TERM...POWER LONG TERM...MASEK AVIATION...CDC FIRE WEATHER...POWER
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
609 PM MDT SAT MAR 21 2015 .AVIATION... 00Z TAF CYCLE THE LAST FEW SHOWERS ARE DISSIPATING OVER CENTRAL/WESTERN NM LATE THIS AFTERNOON. SKIES EXPECTED TO CLEAR OVERNIGHT...LEADING TO PERHAPS SOME SHALLOW FOG AT A FEW SITES ACROSS THE EASTERN PLAINS AND NORTHERN/WESTERN VALLEYS. TOMORROW LOOKS SPECTACULAR WITH JUST SOME LATE AFTERNOON BREEZES NEAR THE ARIZONA BORDER AND EAST SLOPES. GUYER && .PREV DISCUSSION...541 PM MDT SAT MAR 21 2015... .UPDATE... INTERESTINGLY...THOUGH IT IS QUITE DIFFICULT TO GET SE BOUND CONVECTION TO MAKE IT INTO THE ABQ METRO EVEN IN THE SUMMER...HERE IT IS SURVIVING INTO THE NORTH PORTION OF THE METRO. IT SHOULD NOT LAST MORE THAN ANOTHER HALF HOUR TO HOUR AND AMOUNTS WILL BE UNDER A TENTH OF AN INCH...BUT FELT IT WAS ENOUGH TO NECESSITATE A QUICK UPDATE. SO...IT IS THUS. ALSO TWEAKED POPS AND SKY COVER SLIGHTLY IN A FEW OTHER SPOTS. 43 && .PREV DISCUSSION...310 PM MDT SAT MAR 21 2015... .SYNOPSIS... DRYING AND WARMING TREND SUNDAY AND MONDAY WITH SOME AFTERNOON WINDINESS MONDAY. CRITICAL FIRE WEATHER CONDITIONS COULD DEVELOP MONDAY AFTERNOON FROM THE EAST SLOPES OF THE CENTRAL MOUNTAIN CHAIN OVER THE NORTHEAST AND EAST CENTRAL PLAINS. SOMEWHAT COOLER TUESDAY...ALTHOUGH HIGH TEMPERATURES WILL REMAIN ABOVE AVERAGE. THERE IS POTENTIAL FOR A BRIEF PERIOD OF WETTER WEATHER AROUND THE MIDDLE OF NEXT WEEK...BUT FORECAST MODELS DIFFER CONSIDERABLY. A DRYING TREND LOOKS TO RETURN FOR NEXT FRIDAY AND SATURDAY. && .DISCUSSION... PUNY CONVECTION OVER SOME OF THE NORTHERN...WESTERN AND CENTRAL HIGH TERRAIN THIS AFTERNOON. KEPT THE SMALL INHERITED POPS FOR THIS EVENING WITH LITTLE CHANGE...ALTHOUGH BOTH HRRR AND NAM12 MAKE A CASE FOR ISOLATED CELLS THIS EVENING OVER THE FAR NORTHEAST. GIVEN THERE/S NOT MUCH GOING ON OVER THE MTS ON THE COLORADO SIDE OF THE BORDER AT THE MOMENT...THERE/S PROBABLY NOT MUCH CHANCE FOR ONE TO SCORE A DIRECT HIT ON ANY RAINFALL MEASURING BUCKET. OTHERWISE...THERE IS POTENTIAL FOR AT LEAST PATCHY FOG IN THE PECOS VALLEY SOUTH OF INTERSTATE 40 EASTWARD TO THE TEXAS BORDER LATER TONIGHT AND EARLY SUNDAY...INCLUDING THE CLOVIS/PORTALES AREA...WHERE 40S DEWPOINTS FORECAST TO REMAIN IN PLACE AND THE MID TO HIGH LEVEL MOISTURE CLEARS OUT WITH THE DEPARTING LOW/TROUGH. DEW POINTS DRY OUT SUNDAY AS AN WEAK RIDGE BUILDS OVER THE STATE. A SFC LEE TROUGH WILL BE ESTABLISHED...AND TEMPERATURES WILL RANGE FROM AROUND 5 TO NEARLY 20 DEGREES ABOVE AVERAGE...WITH THE GREATEST DEVIATION FROM NORMAL ACROSS NORTH CENTRAL AND NORTHEAST. A TREND TOWARD ZONAL FLOW MONDAY...AND COMBINED WITH THE SFC TROUGH...BREEZY TO WINDY CONDITIONS LOOK TO DEVELOP ESPECIALLY FROM THE CENTRAL MT CHAIN OVER THE NORTHEAST AND EAST CENTRAL PLAINS. WIDESPREAD WIND ADVY CRITERIA DOESN/T APPEAR TO BE LIKELY...HOWEVER...IMPACTS WILL BE FIRE WEATHER RELATED AS HIGHS WILL SOAR IN TO THE UPPER 70S AND 80S MONDAY AFTERNOON OVER THAT PART OF THE FORECAST AREA. HIGH TEMPERATURE DEVIATIONS FROM AVERAGE WILL BE SOMEWHAT SIMILAR TO THOSE OF SUNDAY. TUESDAY WILL BE SLIGHTLY COOLER AS THE SFC TROUGH AND ASSOCIATED SHORT WAVE TRACK NORTHEAST OF NEW MEXICO...LEAVING SOME GUSTY NORTHWEST WINDS TO AFFECT THE CENTRAL MT CHAIN AND ADJACENT HIGHLANDS. FOR THE MID TO LATE WEEK PERIOD...THE ECMWF REMAINS THE WETTER MODEL...COMPARED TO THE GFS...WHICH DEVELOPS 2 SEPARATE FEATURES...A CUTOFF LOW OVER SOCAL...AND A SHORT WAVE IN THE NW FLOW ALOFT WHICH CLIPS NORTHEAST NM. GIVEN THE DIFFERENCES...REINED IN POPULATED POPS FOR WED NIGHT/THURS. FRIDAY AND SATURDAY LOOK DRY...BUT ECMWF DROPS ANOTHER SHORT WAVE INTO NORTHERN NEW MEXICO SUNDAY...WHILE THE GFS BOOTS OUT THE SOCAL LOW FARTHER NORTH AND OVER THE STATE. EITHER WAY...IT LOOKS LIKE SPOTTY PRECIPITATION COULD DEVELOP. && .FIRE WEATHER... ...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE ON MONDAY ACROSS MUCH OF EASTERN NEW MEXICO... LOW PRESSURE SYSTEM ALOFT CONTINUES TO SWING SOUTH OF NM TODAY WITH SOME STEADY BATCHES OF LIGHT PRECIPITATION FAVORING THE SOUTHERN TIER OF THE STATE...MOSTLY OUT OF THE ABQ FIRE WEATHER FORECAST AREA. HOWEVER...SOME REMNANT INSTABILITY AND MOISTURE IS LEADING TO DEVELOPMENT OF NEW SHOWERS AND STORMS OVER THE HIGHER TERRAIN OF CENTRAL NM THIS AFTERNOON. THIS ACTIVITY SHOULD REMAIN FAIRLY ISOLATED WITH LOW PROBABILITIES FOR ACTUAL WETTING RAINFALL...BUT A FEW CLOUD TO GROUND LIGHTNING STRIKES COULD OCCUR. DRIER AIR IN THE MID TO UPPER LEVELS OF THE ATMOSPHERE IS SLOWLY FILTERING INTO THE STATE FROM THE NORTH NORTHWEST...AND THIS TREND WILL PERSIST OVERNIGHT. HOWEVER...THE DEWPOINTS NEAR THE SURFACE WILL BE SLOWER TO RESPOND TO THIS DRYING...THUS ANOTHER NIGHT/MORNING OF EXCELLENT RH RECOVERY IS ANTICIPATED THROUGH EARLY SUNDAY. THE REMNANTS OF THE LOW PRESSURE SYSTEM WILL HAVE FULLY EXITED EAST OF NM ON SUNDAY...GIVING WAY TO A RIDGE OF HIGH PRESSURE. THIS WILL KEEP THE DRYING TREND GOING...WITH LOW LAYER RH/DEWPOINTS ALSO QUICKLY RESPONDING DOWNWARD AS DEEP MIXING ENSUES IN AN ABOVE NORMAL TEMPERATURE REGIME. PRECIPITATION WILL HAVE FULLY ESCAPED AND THE ENTIRE FORECAST AREA SHOULD EXCEED SEASONAL AVERAGES. A WEAK LEE SIDE SURFACE TROUGH WILL STRUGGLE TO TAKE SHAPE...BUT WILL NOT FULLY COME TOGETHER BEFORE DUSK SUNDAY. THE PATTERN TURNS MORE CRITICAL ON MONDAY AS THE RIDGE ALOFT BREAKS DOWN AND STRONGER WESTERLY FLOW ALOFT DEVELOPS OVER NM WITH AVERAGE SPEEDS OF 30-40 MPH IN THE 10000 TO 18000 FT LAYER. THIS WILL BE A NOTABLE STRENGTHENING OF THESE UPPER LEVEL WINDS THAT HAS YET TO TRANSFER TO THE SURFACE THUS FAR THIS YEAR. AS THE LEE SIDE SURFACE CYCLONE BECOMES BETTER ESTABLISHED EXCELLENT MIXING IS FORECAST...AND BREEZY TO WINDY CONDITIONS WILL ENSUE MONDAY AFTERNOON WHILE THE WARMER THAN AVERAGE AND DRY CONDITIONS PERSIST. WIND SPEEDS LOOK TO EXCEED CRITICAL SPEEDS OVER MUCH OF THE NORTHEASTERN QUADRANT OF NM WHERE RH WILL PLUMMET TO 10 TO 15 PERCENT MONDAY AFTERNOON...AND AFTER FURTHER COLLABORATION ON THE STATUS OF THE FINE OR 1-HOUR FUELS...BELIEVE THERE WILL BE ENOUGH FIRE DANGER JUXTAPOSED WITH THE CRITICAL WINDS/RH. THUS...A WATCH WILL BE HOISTED WITH THIS FORECAST PACKAGE. A SHORT WAVE TROUGH WILL PASS NORTH OF NM MONDAY NIGHT...KEEPING WINDS ALOFT STRONG...AND SOME MOUNTAIN WAVE ACTIVITY MAY EVEN CRASH EAST OF THE SANGRE DE CRISTOS INTO EARLY TUESDAY MORNING. THE REMAINDER OF TUESDAY SHOULD SEE A DECREASE IN SPEEDS ALOFT WITH SLIGHTLY COOLER...BUT STILL ABOVE AVERAGE TEMPERATURES PREVAILING. THE NEXT NOTABLE FEATURE WILL APPROACH ON THURSDAY AS A TROUGH DIVES SOUTHEAST OUT OF CANADA AND ADDITIONAL ENERGY SEPARATES AND CUTS OFF ON A TRAJECTORY NEAR OR WEST OF NM. FORECAST MODELS ARE HAVING DIFFICULTY RETAINING CONTINUITY BETWEEN RUNS AND AMONGST EACH OTHER. THE IMPACTS FROM THE COLDER AIR AND PRECIPITATION SEEM LESS CERTAIN ACCORDING TO THE GFS...WHILE THE EUROPEAN MODEL IS MORE ASSERTIVE WITH BOTH. 52 && .ABQ WATCHES/WARNINGS/ADVISORIES... FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR THE FOLLOWING ZONES...NMZ103-104-107-108. && $$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
541 PM MDT SAT MAR 21 2015 .UPDATE... INTERESTINGLY...THOUGH IT IS QUITE DIFFICULT TO GET SE BOUND CONVECTION TO MAKE IT INTO THE ABQ METRO EVEN IN THE SUMMER...HERE IT IS SURVIVING INTO THE NORTH PORTION OF THE METRO. IT SHOULD NOT LAST MORE THAN ANOTHER HALF HOUR TO HOUR AND AMOUNTS WILL BE UNDER A TENTH OF AN INCH...BUT FELT IT WAS ENOUGH TO NECESSITATE A QUICK UPDATE. SO...IT IS THUS. ALSO TWEAKED POPS AND SKY COVER SLIGHTLY IN A FEW OTHER SPOTS. 43 && .PREV DISCUSSION...310 PM MDT SAT MAR 21 2015... .SYNOPSIS... DRYING AND WARMING TREND SUNDAY AND MONDAY WITH SOME AFTERNOON WINDINESS MONDAY. CRITICAL FIRE WEATHER CONDITIONS COULD DEVELOP MONDAY AFTERNOON FROM THE EAST SLOPES OF THE CENTRAL MOUNTAIN CHAIN OVER THE NORTHEAST AND EAST CENTRAL PLAINS. SOMEWHAT COOLER TUESDAY...ALTHOUGH HIGH TEMPERATURES WILL REMAIN ABOVE AVERAGE. THERE IS POTENTIAL FOR A BRIEF PERIOD OF WETTER WEATHER AROUND THE MIDDLE OF NEXT WEEK...BUT FORECAST MODELS DIFFER CONSIDERABLY. A DRYING TREND LOOKS TO RETURN FOR NEXT FRIDAY AND SATURDAY. && .DISCUSSION... PUNY CONVECTION OVER SOME OF THE NORTHERN...WESTERN AND CENTRAL HIGH TERRAIN THIS AFTERNOON. KEPT THE SMALL INHERITED POPS FOR THIS EVENING WITH LITTLE CHANGE...ALTHOUGH BOTH HRRR AND NAM12 MAKE A CASE FOR ISOLATED CELLS THIS EVENING OVER THE FAR NORTHEAST. GIVEN THERE/S NOT MUCH GOING ON OVER THE MTS ON THE COLORADO SIDE OF THE BORDER AT THE MOMENT...THERE/S PROBABLY NOT MUCH CHANCE FOR ONE TO SCORE A DIRECT HIT ON ANY RAINFALL MEASURING BUCKET. OTHERWISE...THERE IS POTENTIAL FOR AT LEAST PATCHY FOG IN THE PECOS VALLEY SOUTH OF INTERSTATE 40 EASTWARD TO THE TEXAS BORDER LATER TONIGHT AND EARLY SUNDAY...INCLUDING THE CLOVIS/PORTALES AREA...WHERE 40S DEWPOINTS FORECAST TO REMAIN IN PLACE AND THE MID TO HIGH LEVEL MOISTURE CLEARS OUT WITH THE DEPARTING LOW/TROUGH. DEW POINTS DRY OUT SUNDAY AS AN WEAK RIDGE BUILDS OVER THE STATE. A SFC LEE TROUGH WILL BE ESTABLISHED...AND TEMPERATURES WILL RANGE FROM AROUND 5 TO NEARLY 20 DEGREES ABOVE AVERAGE...WITH THE GREATEST DEVIATION FROM NORMAL ACROSS NORTH CENTRAL AND NORTHEAST. A TREND TOWARD ZONAL FLOW MONDAY...AND COMBINED WITH THE SFC TROUGH...BREEZY TO WINDY CONDITIONS LOOK TO DEVELOP ESPECIALLY FROM THE CENTRAL MT CHAIN OVER THE NORTHEAST AND EAST CENTRAL PLAINS. WIDESPREAD WIND ADVY CRITERIA DOESN/T APPEAR TO BE LIKELY...HOWEVER...IMPACTS WILL BE FIRE WEATHER RELATED AS HIGHS WILL SOAR IN TO THE UPPER 70S AND 80S MONDAY AFTERNOON OVER THAT PART OF THE FORECAST AREA. HIGH TEMPERATURE DEVIATIONS FROM AVERAGE WILL BE SOMEWHAT SIMILAR TO THOSE OF SUNDAY. TUESDAY WILL BE SLIGHTLY COOLER AS THE SFC TROUGH AND ASSOCIATED SHORT WAVE TRACK NORTHEAST OF NEW MEXICO...LEAVING SOME GUSTY NORTHWEST WINDS TO AFFECT THE CENTRAL MT CHAIN AND ADJACENT HIGHLANDS. FOR THE MID TO LATE WEEK PERIOD...THE ECMWF REMAINS THE WETTER MODEL...COMPARED TO THE GFS...WHICH DEVELOPS 2 SEPARATE FEATURES...A CUTOFF LOW OVER SOCAL...AND A SHORT WAVE IN THE NW FLOW ALOFT WHICH CLIPS NORTHEAST NM. GIVEN THE DIFFERENCES...REINED IN POPULATED POPS FOR WED NIGHT/THURS. FRIDAY AND SATURDAY LOOK DRY...BUT ECMWF DROPS ANOTHER SHORT WAVE INTO NORTHERN NEW MEXICO SUNDAY...WHILE THE GFS BOOTS OUT THE SOCAL LOW FARTHER NORTH AND OVER THE STATE. EITHER WAY...IT LOOKS LIKE SPOTTY PRECIPITATION COULD DEVELOP. && .FIRE WEATHER... ...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE ON MONDAY ACROSS MUCH OF EASTERN NEW MEXICO... LOW PRESSURE SYSTEM ALOFT CONTINUES TO SWING SOUTH OF NM TODAY WITH SOME STEADY BATCHES OF LIGHT PRECIPITATION FAVORING THE SOUTHERN TIER OF THE STATE...MOSTLY OUT OF THE ABQ FIRE WEATHER FORECAST AREA. HOWEVER...SOME REMNANT INSTABILITY AND MOISTURE IS LEADING TO DEVELOPMENT OF NEW SHOWERS AND STORMS OVER THE HIGHER TERRAIN OF CENTRAL NM THIS AFTERNOON. THIS ACTIVITY SHOULD REMAIN FAIRLY ISOLATED WITH LOW PROBABILITIES FOR ACTUAL WETTING RAINFALL...BUT A FEW CLOUD TO GROUND LIGHTNING STRIKES COULD OCCUR. DRIER AIR IN THE MID TO UPPER LEVELS OF THE ATMOSPHERE IS SLOWLY FILTERING INTO THE STATE FROM THE NORTH NORTHWEST...AND THIS TREND WILL PERSIST OVERNIGHT. HOWEVER...THE DEWPOINTS NEAR THE SURFACE WILL BE SLOWER TO RESPOND TO THIS DRYING...THUS ANOTHER NIGHT/MORNING OF EXCELLENT RH RECOVERY IS ANTICIPATED THROUGH EARLY SUNDAY. THE REMNANTS OF THE LOW PRESSURE SYSTEM WILL HAVE FULLY EXITED EAST OF NM ON SUNDAY...GIVING WAY TO A RIDGE OF HIGH PRESSURE. THIS WILL KEEP THE DRYING TREND GOING...WITH LOW LAYER RH/DEWPOINTS ALSO QUICKLY RESPONDING DOWNWARD AS DEEP MIXING ENSUES IN AN ABOVE NORMAL TEMPERATURE REGIME. PRECIPITATION WILL HAVE FULLY ESCAPED AND THE ENTIRE FORECAST AREA SHOULD EXCEED SEASONAL AVERAGES. A WEAK LEE SIDE SURFACE TROUGH WILL STRUGGLE TO TAKE SHAPE...BUT WILL NOT FULLY COME TOGETHER BEFORE DUSK SUNDAY. THE PATTERN TURNS MORE CRITICAL ON MONDAY AS THE RIDGE ALOFT BREAKS DOWN AND STRONGER WESTERLY FLOW ALOFT DEVELOPS OVER NM WITH AVERAGE SPEEDS OF 30-40 MPH IN THE 10000 TO 18000 FT LAYER. THIS WILL BE A NOTABLE STRENGTHENING OF THESE UPPER LEVEL WINDS THAT HAS YET TO TRANSFER TO THE SURFACE THUS FAR THIS YEAR. AS THE LEE SIDE SURFACE CYCLONE BECOMES BETTER ESTABLISHED EXCELLENT MIXING IS FORECAST...AND BREEZY TO WINDY CONDITIONS WILL ENSUE MONDAY AFTERNOON WHILE THE WARMER THAN AVERAGE AND DRY CONDITIONS PERSIST. WIND SPEEDS LOOK TO EXCEED CRITICAL SPEEDS OVER MUCH OF THE NORTHEASTERN QUADRANT OF NM WHERE RH WILL PLUMMET TO 10 TO 15 PERCENT MONDAY AFTERNOON...AND AFTER FURTHER COLLABORATION ON THE STATUS OF THE FINE OR 1-HOUR FUELS...BELIEVE THERE WILL BE ENOUGH FIRE DANGER JUXTAPOSED WITH THE CRITICAL WINDS/RH. THUS...A WATCH WILL BE HOISTED WITH THIS FORECAST PACKAGE. A SHORT WAVE TROUGH WILL PASS NORTH OF NM MONDAY NIGHT...KEEPING WINDS ALOFT STRONG...AND SOME MOUNTAIN WAVE ACTIVITY MAY EVEN CRASH EAST OF THE SANGRE DE CRISTOS INTO EARLY TUESDAY MORNING. THE REMAINDER OF TUESDAY SHOULD SEE A DECREASE IN SPEEDS ALOFT WITH SLIGHTLY COOLER...BUT STILL ABOVE AVERAGE TEMPERATURES PREVAILING. THE NEXT NOTABLE FEATURE WILL APPROACH ON THURSDAY AS A TROUGH DIVES SOUTHEAST OUT OF CANADA AND ADDITIONAL ENERGY SEPARATES AND CUTS OFF ON A TRAJECTORY NEAR OR WEST OF NM. FORECAST MODELS ARE HAVING DIFFICULTY RETAINING CONTINUITY BETWEEN RUNS AND AMONGST EACH OTHER. THE IMPACTS FROM THE COLDER AIR AND PRECIPITATION SEEM LESS CERTAIN ACCORDING TO THE GFS...WHILE THE EUROPEAN MODEL IS MORE ASSERTIVE WITH BOTH. 52 && .AVIATION... 18Z TAF CYCLE NEW CUMULUS CLOUDS ARE STARTING TO BUBBLE UP OVER THE HIGHER TERRAIN OF CENTRAL TO WESTERN NEW MEXICO EARLY THIS AFTERNOON...AND ISOLATED TO SCATTERED SHOWERS ARE EXPECTED TO TAKE SHAPE INTO THE MID AFTERNOON. ACTIVITY WILL GENERALLY DRIFT FROM NORTHWEST TO SOUTHEAST AT ABOUT 10 TO 15 MPH WITH GUSTY OUTFLOW WINDS AND SMALL HAIL POSSIBLE. ANY REDUCTIONS TO CEILINGS/VISIBILITIES IN DOWNPOURS WILL BE VERY BRIEF. THERE IS POTENTIAL FOR SOME LOW STRATUS CLOUDS/FOG TO DEVELOP IN THE PECOS VALLEY AND TOWARD THE EAST CENTRAL PLAINS OF NEW MEXICO LATE TONIGHT AND INTO EARLY SUNDAY MORNING. LOCALIZED MVFR TO IFR/LIFR CONDITIONS WOULD BE POSSIBLE...GENERALLY EAST OF A KROW TO KCVN LINE. 52 && .ABQ WATCHES/WARNINGS/ADVISORIES... FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR THE FOLLOWING ZONES...NMZ103-104-107-108. && $$ 43
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1141 AM MDT FRI MAR 20 2015 .AVIATION... 18Z TAF CYCLE SCATTERED MVFR CEILINGS DUE TO LOW STRATUS CLOUDS HAVE LINGERED OVER PARTS OF NORTHERN AND CENTRAL NEW MEXICO AFTER FAIRLY WIDESPREAD PRECIPITATION LATE YESTERDAY AND LAST NIGHT. FOG HAS DISSIPATED...BUT SOME ISOLATED LOCATIONS SUCH AS KCQC AND KSRR ARE OBSERVING LOWER CEILINGS IN THE IFR/LIFR CATEGORIES. CEILINGS WILL RISE THROUGH THE LATE AFTERNOON WITH SOME ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING...NAMELY ALONG AND SURROUNDING THE CONTINENTAL DIVIDE IN WESTERN NEW MEXICO. SMALL HAIL AND GUSTY DOWNBURST WINDS WILL BE POSSIBLE WITH THIS ACTIVITY...BUT SHOWERS/STORMS SHOULD MOSTLY DISSIPATE INTO THE EARLY EVENING. SOME LOW STRATUS CLOUDS AND PERHAPS FOG WILL REDEVELOP IN THE LOWER PECOS VALLEY LATE TONIGHT INTO EARLY SATURDAY MORNING...NEAR KROW AND POTENTIALLY IN SOME WEST CENTRAL VALLEYS...SUCH AS KGUP. CONFIDENCE IS LOW ON EXACT EXTENT OF ANY LOW CLOUDS/FOG DEVELOPMENT TONIGHT/SATURDAY MORNING...THUS TAFS ARE NOT OVERLY PESSIMISTIC. && .PREV DISCUSSION...722 AM MDT FRI MAR 20 2015... .UPDATE... QUICK UPDATE TO LOWER POPS FOR THE MORNING PERIOD. SHOWERS HAVE LARGELY DISSIPATED THIS MORNING...EXCEPT AROUND GRANTS. THOUGH SOME WILL LIKELY REDEVELOP BEFORE 18Z...BEST COVERAGE WILL NOT BE UNTIL THE AFTERNOON. UPDATES ALREADY OUT. 34 && .PREV DISCUSSION...315 AM MDT FRI MAR 20 2015... .SYNOPSIS... RAIN CONTINUES THIS MORNING ACROSS PORTIONS OF CENTRAL AND WEST CENTRAL NEW MEXICO. THOUGH THIS ACTIVITY WILL DIMINISH LATER THIS MORNING...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON. COVERAGE WILL NOT BE AS WIDESPREAD AS YESTERDAY...NOR WILL AMOUNTS BE AS GREAT. NONETHELESS...PORTIONS OF WESTERN NEW MEXICO WILL BE FAVORED. ON SATURDAY...PRECIPITATION CHANCES WILL FAVOR SOUTH CENTRAL AND SOUTHEASTERN PORTIONS OF THE AREA...THOUGH SPOTTY HIGH TERRAIN STORMS WILL BE POSSIBLE ELSEWHERE. EARLY NEXT WEEK...DRY AND BREEZY CONDITIONS...MORE TYPICAL OF MARCH...ARE EXPECTED. && .DISCUSSION... RAIN IS PERSISTING THIS MORNING FROM JUST SOUTH OF THE JEMEZ MTNS...SOUTH-SOUTHWESTWARD TOWARD THE WEST CENTRAL AND SW MTNS. THIS AREA OF RAIN APPEARS TO BE WITHIN THE DEFORMATION ZONE OF THE UPPER LEVEL TROUGH...BUT AS THIS BECOMES MORE ILL-DEFINED...RAIN SHOULD SLOWLY DIMINISH THROUGH THE MORNING HOURS. FURTHER NORTH...A FEW SPRINKLES OR FLURRIES CONTINUE...BUT BY AND LARGE...PRECIPITATION HAS ENDED IN THIS AREA. THEREFORE...WILL CANCEL THE WINTER HIGHLIGHTS WITH THIS MORNINGS PACKAGE. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON...THOUGH THE BEST LIFT FROM THE UPPER LEVEL LOW WILL BE ACROSS SOUTHWEST PORTIONS OF THE CWA. MODELS CONTINUE TO TREND BACK QPF AMOUNTS ACROSS THE CENTRAL MTN CHAIN...THOUGH THE HRRR SUGGESTS SOME SCATTERED LIGHT POPCORN CONVECTION THIS AFTN. REGARDLESS...NOT LOOKING FOR PRECIPITATION COVERAGE TO BE AS WIDESPREAD AS YESTERDAY...AND THE BEST CHANCES FOR WETTING RAINS LOOK TO BE ACROSS THE SW MTNS. THE TROUGH/LOW WILL CONTINUE TO WEAKEN AS IT SHIFTS NORTHEASTWARD ON SATURDAY...CROSSING FAR SE NM IN THE AFTN. HOWEVER...MODELS ARE NOW SHOWING A BETTER CHANCE FOR PRECIP TO BULGE NORTHWARD INTO SC AND SE PORTIONS OF THE CWA. HAVE INCREASED POPS IN THESE AREAS AND TRENDED TEMPS DOWNWARD ACCORDINGLY. ELSEWHERE...SPOTTY SHOWERS OR A T-STORM MAY DEVELOP OVER THE HIGHER TERRAIN...BUT THE DRIER AIR MOVING IN WILL START TO TAKE ITS TOLL. BY SUNDAY...THE TROUGH WILL BE EAST OF NM AND MUCH DRIER AIR BENEATH A WEAK RIDGE WILL ELIMINATE PRECIPITATION CHANCES. STRENGTHENING WESTERLY FLOW ALOFT AND THE DEVELOPMENT OF A SURFACE LOW OVER SE CO WILL RESULT IN A DRY AND WINDY DAY ON MONDAY...WITH SIMILAR CONDITIONS ON TUESDAY. TEMPERATURES WILL WARM WELL ABOVE NORMAL...ESPECIALLY ACROSS THE EAST DUE TO COMPRESSIONAL WARMING. MODELS REMAIN AT ODDS REGARDING THE TIMING AND STRENGTH OF THE NEXT SYSTEM SOMETIME MID TO LATE WEEK. THE STRENGTH AND TIMING OF THE ASSOCIATED BACK DOOR COLD FRONT IS IN QUESTION AS WELL...WHICH WILL HAVE IMPACTS ON PRECIPITATION CHANCES. STAY TUNED. 34 && .FIRE WEATHER... MOIST ATMOSPHERE TO GRADUALLY DRY OUT THROUGH THE WEEKEND. EARLY NEXT WEEK WILL BE DRY AND WARM WITH INCREASING WINDS...CREATING THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS. STORM OVER BAJA CA WILL CONTINUE TO BRING WIDESPREAD SHOWERS TODAY FAVORING THE WEST AND CENTRAL AREAS. THERE WILL BE A FEW STORMS AS WELL. TEMPERATURES WILL BE MILDER IN THE NORTHEAST AND COOLER IN THE SOUTHEAST WITH NOT MUCH CHANGE ELSEWHERE. MINIMUM RH VALUES WILL BE MUCH LOWER IN THE NORTHEAST. VENT RATES WILL BE POOR IN THE EAST AND CENTRAL AREAS AND FAIR TO GOOD IN THE WEST. RAIN SHOWERS AND MOUNTAIN SNOW SHOWERS WILL CONTINUE TONIGHT WITH A FEW STORMS THIS EVENING. PRECIPITATION WILL AGAIN FAVOR WEST AND CENTRAL AREAS. RH RECOVERIES WILL BE EXCELLENT. A GRADUAL DRYING AND WARMING TREND WILL BEGIN THIS WEEKEND AND CONTINUE EARLY NEXT WEEK. ISOLATED SHOWERS WILL FAVOR THE WESTERN AND CENTRAL MOUNTAINS SATURDAY...THEN IT WILL BE DRY AREA WIDE SUNDAY. WETTING RAINS WILL BE SCARCE SATURDAY...IF ANY AT ALL. TEMPERATURES WILL INCREASE 5 TO 10 DEGREES EACH DAY THIS WEEKEND WHILE MINIMUM RH VALUES PLUMMET...WITH MOSTLY TEENS ON SUNDAY ASIDE FROM THE 20S OVER THE HIGHER TERRAIN. VENT RATES WILL IMPROVE WITH THE ONLY POOR RATES IN THE NORTHEAST SATURDAY...THEN GOOD TO EXCELLENT SUNDAY. THE WARM AND DRY WEATHER WILL CONTINUE EARLY NEXT WEEK WITH THE FLOW ALOFT INCREASING OUT OF THE WEST. THIS WILL HELP PRODUCE STRONGER SURFACE WINDS ALONG WITH THE DEVELOPMENT OF A LEE SIDE TROUGH IN THE EAST. CRITICAL FIRE WEATHER CONDITIONS WILL BE APPROACHED ON MONDAY ACROSS EASTERN PORTIONS OF ZONE 106...THEN REACHED FOR A FEW HOURS ON TUESDAY. MAIN THREAT TUESDAY WILL BE FROM CLINES CORNERS TO SANTA ROSA. VENT RATES WILL BE GOOD TO EXCELLENT MONDAY AND TUESDAY. A DEEPENING SHORT WAVE TROUGH TO OUR NORTHWEST WEDNESDAY WILL DROP A BACK DOOR COLD FRONT INTO THE EAST WITH COOLER TEMPERATURES FOR ALL AREAS...ESPECIALLY THE EAST. THIS WILL ELIMINATE CRITICAL FIRE WEATHER CONCERNS AS MINIMUM RH VALUES RISE INTO THE 20S ACROSS THE EAST. SHOWERS WILL DEVELOP OVER THE WEST AND NORTH MOUNTAINS WEDNESDAY AND SPREAD ACROSS MUCH OF THE AREA THURSDAY INTO FRIDAY. TEMPERATURES WILL CONTINUE TO COOL TO BELOW NORMAL LEVELS WHILE RH VALUES INCREASE SHARPLY. CHJ && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
722 AM MDT FRI MAR 20 2015 .UPDATE... QUICK UPDATE TO LOWER POPS FOR THE MORNING PERIOD. SHOWERS HAVE LARGELY DISSIPATED THIS MORNING...EXCEPT AROUND GRANTS. THOUGH SOME WILL LIKELY REDEVELOP BEFORE 18Z...BEST COVERAGE WILL NOT BE UNTIL THE AFTERNOON. UPDATES ALREADY OUT. 34 && .PREV DISCUSSION...606 AM MDT FRI MAR 20 2015... .AVIATION... 12Z TAF CYCLE SHOWERS GRADUALLY DIMINISHING OVER CIBOLA...SOUTHERN SANDOVAL AND WEST CENTRAL SANTA FE COUNTIES. THEY SHOULD END BY 15Z. PATCHY DENSE FOG WITH LIFR CONDITIONS AT LAM AND SRR SHOULD IMPROVE TO VFR BY LATE MORNING. OTHERWISE MOSTLY VFR CONDITIONS TODAY EXCEPT MVFR IN SHOWERS/STORMS THAT DEVELOP THROUGHOUT THE DAY. MAIN PRECIPITATION COVERAGE OVER THE HIGHER TERRAIN. TOUGH CALL TONIGHT ON EXTENT OF LOW CLOUDS AND FOG THAT MAY FORM. WILL BE OPTIMISTIC AND KEEP TAFS MOSTLY VFR. && .PREV DISCUSSION...315 AM MDT FRI MAR 20 2015... .SYNOPSIS... RAIN CONTINUES THIS MORNING ACROSS PORTIONS OF CENTRAL AND WEST CENTRAL NEW MEXICO. THOUGH THIS ACTIVITY WILL DIMINISH LATER THIS MORNING...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON. COVERAGE WILL NOT BE AS WIDESPREAD AS YESTERDAY...NOR WILL AMOUNTS BE AS GREAT. NONETHELESS...PORTIONS OF WESTERN NEW MEXICO WILL BE FAVORED. ON SATURDAY...PRECIPITATION CHANCES WILL FAVOR SOUTH CENTRAL AND SOUTHEASTERN PORTIONS OF THE AREA...THOUGH SPOTTY HIGH TERRAIN STORMS WILL BE POSSIBLE ELSEWHERE. EARLY NEXT WEEK...DRY AND BREEZY CONDITIONS...MORE TYPICAL OF MARCH...ARE EXPECTED. && .DISCUSSION... RAIN IS PERSISTING THIS MORNING FROM JUST SOUTH OF THE JEMEZ MTNS...SOUTH-SOUTHWESTWARD TOWARD THE WEST CENTRAL AND SW MTNS. THIS AREA OF RAIN APPEARS TO BE WITHIN THE DEFORMATION ZONE OF THE UPPER LEVEL TROUGH...BUT AS THIS BECOMES MORE ILL-DEFINED...RAIN SHOULD SLOWLY DIMINISH THROUGH THE MORNING HOURS. FURTHER NORTH...A FEW SPRINKLES OR FLURRIES CONTINUE...BUT BY AND LARGE...PRECIPITATION HAS ENDED IN THIS AREA. THEREFORE...WILL CANCEL THE WINTER HIGHLIGHTS WITH THIS MORNINGS PACKAGE. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON...THOUGH THE BEST LIFT FROM THE UPPER LEVEL LOW WILL BE ACROSS SOUTHWEST PORTIONS OF THE CWA. MODELS CONTINUE TO TREND BACK QPF AMOUNTS ACROSS THE CENTRAL MTN CHAIN...THOUGH THE HRRR SUGGESTS SOME SCATTERED LIGHT POPCORN CONVECTION THIS AFTN. REGARDLESS...NOT LOOKING FOR PRECIPITATION COVERAGE TO BE AS WIDESPREAD AS YESTERDAY...AND THE BEST CHANCES FOR WETTING RAINS LOOK TO BE ACROSS THE SW MTNS. THE TROUGH/LOW WILL CONTINUE TO WEAKEN AS IT SHIFTS NORTHEASTWARD ON SATURDAY...CROSSING FAR SE NM IN THE AFTN. HOWEVER...MODELS ARE NOW SHOWING A BETTER CHANCE FOR PRECIP TO BULGE NORTHWARD INTO SC AND SE PORTIONS OF THE CWA. HAVE INCREASED POPS IN THESE AREAS AND TRENDED TEMPS DOWNWARD ACCORDINGLY. ELSEWHERE...SPOTTY SHOWERS OR A T-STORM MAY DEVELOP OVER THE HIGHER TERRAIN...BUT THE DRIER AIR MOVING IN WILL START TO TAKE ITS TOLL. BY SUNDAY...THE TROUGH WILL BE EAST OF NM AND MUCH DRIER AIR BENEATH A WEAK RIDGE WILL ELIMINATE PRECIPITATION CHANCES. STRENGTHENING WESTERLY FLOW ALOFT AND THE DEVELOPMENT OF A SURFACE LOW OVER SE CO WILL RESULT IN A DRY AND WINDY DAY ON MONDAY...WITH SIMILAR CONDITIONS ON TUESDAY. TEMPERATURES WILL WARM WELL ABOVE NORMAL...ESPECIALLY ACROSS THE EAST DUE TO COMPRESSIONAL WARMING. MODELS REMAIN AT ODDS REGARDING THE TIMING AND STRENGTH OF THE NEXT SYSTEM SOMETIME MID TO LATE WEEK. THE STRENGTH AND TIMING OF THE ASSOCIATED BACK DOOR COLD FRONT IS IN QUESTION AS WELL...WHICH WILL HAVE IMPACTS ON PRECIPITATION CHANCES. STAY TUNED. 34 && .FIRE WEATHER... MOIST ATMOSPHERE TO GRADUALLY DRY OUT THROUGH THE WEEKEND. EARLY NEXT WEEK WILL BE DRY AND WARM WITH INCREASING WINDS...CREATING THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS. STORM OVER BAJA CA WILL CONTINUE TO BRING WIDESPREAD SHOWERS TODAY FAVORING THE WEST AND CENTRAL AREAS. THERE WILL BE A FEW STORMS AS WELL. TEMPERATURES WILL BE MILDER IN THE NORTHEAST AND COOLER IN THE SOUTHEAST WITH NOT MUCH CHANGE ELSEWHERE. MINIMUM RH VALUES WILL BE MUCH LOWER IN THE NORTHEAST. VENT RATES WILL BE POOR IN THE EAST AND CENTRAL AREAS AND FAIR TO GOOD IN THE WEST. RAIN SHOWERS AND MOUNTAIN SNOW SHOWERS WILL CONTINUE TONIGHT WITH A FEW STORMS THIS EVENING. PRECIPITATION WILL AGAIN FAVOR WEST AND CENTRAL AREAS. RH RECOVERIES WILL BE EXCELLENT. A GRADUAL DRYING AND WARMING TREND WILL BEGIN THIS WEEKEND AND CONTINUE EARLY NEXT WEEK. ISOLATED SHOWERS WILL FAVOR THE WESTERN AND CENTRAL MOUNTAINS SATURDAY...THEN IT WILL BE DRY AREA WIDE SUNDAY. WETTING RAINS WILL BE SCARCE SATURDAY...IF ANY AT ALL. TEMPERATURES WILL INCREASE 5 TO 10 DEGREES EACH DAY THIS WEEKEND WHILE MINIMUM RH VALUES PLUMMET...WITH MOSTLY TEENS ON SUNDAY ASIDE FROM THE 20S OVER THE HIGHER TERRAIN. VENT RATES WILL IMPROVE WITH THE ONLY POOR RATES IN THE NORTHEAST SATURDAY...THEN GOOD TO EXCELLENT SUNDAY. THE WARM AND DRY WEATHER WILL CONTINUE EARLY NEXT WEEK WITH THE FLOW ALOFT INCREASING OUT OF THE WEST. THIS WILL HELP PRODUCE STRONGER SURFACE WINDS ALONG WITH THE DEVELOPMENT OF A LEE SIDE TROUGH IN THE EAST. CRITICAL FIRE WEATHER CONDITIONS WILL BE APPROACHED ON MONDAY ACROSS EASTERN PORTIONS OF ZONE 106...THEN REACHED FOR A FEW HOURS ON TUESDAY. MAIN THREAT TUESDAY WILL BE FROM CLINES CORNERS TO SANTA ROSA. VENT RATES WILL BE GOOD TO EXCELLENT MONDAY AND TUESDAY. A DEEPENING SHORT WAVE TROUGH TO OUR NORTHWEST WEDNESDAY WILL DROP A BACK DOOR COLD FRONT INTO THE EAST WITH COOLER TEMPERATURES FOR ALL AREAS...ESPECIALLY THE EAST. THIS WILL ELIMINATE CRITICAL FIRE WEATHER CONCERNS AS MINIMUM RH VALUES RISE INTO THE 20S ACROSS THE EAST. SHOWERS WILL DEVELOP OVER THE WEST AND NORTH MOUNTAINS WEDNESDAY AND SPREAD ACROSS MUCH OF THE AREA THURSDAY INTO FRIDAY. TEMPERATURES WILL CONTINUE TO COOL TO BELOW NORMAL LEVELS WHILE RH VALUES INCREASE SHARPLY. CHJ && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 34
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
606 AM MDT FRI MAR 20 2015 .AVIATION... 12Z TAF CYCLE SHOWERS GRADUALLY DIMINISHING OVER CIBOLA...SOUTHERN SANDOVAL AND WEST CENTRAL SANTA FE COUNTIES. THEY SHOULD END BY 15Z. PATCHY DENSE FOG WITH LIFR CONDITIONS AT LAM AND SRR SHOULD IMPROVE TO VFR BY LATE MORNING. OTHERWISE MOSTLY VFR CONDITIONS TODAY EXCEPT MVFR IN SHOWERS/STORMS THAT DEVELOP THROUGHOUT THE DAY. MAIN PRECIPITATION COVERAGE OVER THE HIGHER TERRAIN. TOUGH CALL TONIGHT ON EXTENT OF LOW CLOUDS AND FOG THAT MAY FORM. WILL BE OPTIMISTIC AND KEEP TAFS MOSTLY VFR. && .PREV DISCUSSION...315 AM MDT FRI MAR 20 2015... .SYNOPSIS... RAIN CONTINUES THIS MORNING ACROSS PORTIONS OF CENTRAL AND WEST CENTRAL NEW MEXICO. THOUGH THIS ACTIVITY WILL DIMINISH LATER THIS MORNING...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON. COVERAGE WILL NOT BE AS WIDESPREAD AS YESTERDAY...NOR WILL AMOUNTS BE AS GREAT. NONETHELESS...PORTIONS OF WESTERN NEW MEXICO WILL BE FAVORED. ON SATURDAY...PRECIPITATION CHANCES WILL FAVOR SOUTH CENTRAL AND SOUTHEASTERN PORTIONS OF THE AREA...THOUGH SPOTTY HIGH TERRAIN STORMS WILL BE POSSIBLE ELSEWHERE. EARLY NEXT WEEK...DRY AND BREEZY CONDITIONS...MORE TYPICAL OF MARCH...ARE EXPECTED. && .DISCUSSION... RAIN IS PERSISTING THIS MORNING FROM JUST SOUTH OF THE JEMEZ MTNS...SOUTH-SOUTHWESTWARD TOWARD THE WEST CENTRAL AND SW MTNS. THIS AREA OF RAIN APPEARS TO BE WITHIN THE DEFORMATION ZONE OF THE UPPER LEVEL TROUGH...BUT AS THIS BECOMES MORE ILL-DEFINED...RAIN SHOULD SLOWLY DIMINISH THROUGH THE MORNING HOURS. FURTHER NORTH...A FEW SPRINKLES OR FLURRIES CONTINUE...BUT BY AND LARGE...PRECIPITATION HAS ENDED IN THIS AREA. THEREFORE...WILL CANCEL THE WINTER HIGHLIGHTS WITH THIS MORNINGS PACKAGE. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON...THOUGH THE BEST LIFT FROM THE UPPER LEVEL LOW WILL BE ACROSS SOUTHWEST PORTIONS OF THE CWA. MODELS CONTINUE TO TREND BACK QPF AMOUNTS ACROSS THE CENTRAL MTN CHAIN...THOUGH THE HRRR SUGGESTS SOME SCATTERED LIGHT POPCORN CONVECTION THIS AFTN. REGARDLESS...NOT LOOKING FOR PRECIPITATION COVERAGE TO BE AS WIDESPREAD AS YESTERDAY...AND THE BEST CHANCES FOR WETTING RAINS LOOK TO BE ACROSS THE SW MTNS. THE TROUGH/LOW WILL CONTINUE TO WEAKEN AS IT SHIFTS NORTHEASTWARD ON SATURDAY...CROSSING FAR SE NM IN THE AFTN. HOWEVER...MODELS ARE NOW SHOWING A BETTER CHANCE FOR PRECIP TO BULGE NORTHWARD INTO SC AND SE PORTIONS OF THE CWA. HAVE INCREASED POPS IN THESE AREAS AND TRENDED TEMPS DOWNWARD ACCORDINGLY. ELSEWHERE...SPOTTY SHOWERS OR A T-STORM MAY DEVELOP OVER THE HIGHER TERRAIN...BUT THE DRIER AIR MOVING IN WILL START TO TAKE ITS TOLL. BY SUNDAY...THE TROUGH WILL BE EAST OF NM AND MUCH DRIER AIR BENEATH A WEAK RIDGE WILL ELIMINATE PRECIPITATION CHANCES. STRENGTHENING WESTERLY FLOW ALOFT AND THE DEVELOPMENT OF A SURFACE LOW OVER SE CO WILL RESULT IN A DRY AND WINDY DAY ON MONDAY...WITH SIMILAR CONDITIONS ON TUESDAY. TEMPERATURES WILL WARM WELL ABOVE NORMAL...ESPECIALLY ACROSS THE EAST DUE TO COMPRESSIONAL WARMING. MODELS REMAIN AT ODDS REGARDING THE TIMING AND STRENGTH OF THE NEXT SYSTEM SOMETIME MID TO LATE WEEK. THE STRENGTH AND TIMING OF THE ASSOCIATED BACK DOOR COLD FRONT IS IN QUESTION AS WELL...WHICH WILL HAVE IMPACTS ON PRECIPITATION CHANCES. STAY TUNED. 34 && .FIRE WEATHER... MOIST ATMOSPHERE TO GRADUALLY DRY OUT THROUGH THE WEEKEND. EARLY NEXT WEEK WILL BE DRY AND WARM WITH INCREASING WINDS...CREATING THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS. STORM OVER BAJA CA WILL CONTINUE TO BRING WIDESPREAD SHOWERS TODAY FAVORING THE WEST AND CENTRAL AREAS. THERE WILL BE A FEW STORMS AS WELL. TEMPERATURES WILL BE MILDER IN THE NORTHEAST AND COOLER IN THE SOUTHEAST WITH NOT MUCH CHANGE ELSEWHERE. MINIMUM RH VALUES WILL BE MUCH LOWER IN THE NORTHEAST. VENT RATES WILL BE POOR IN THE EAST AND CENTRAL AREAS AND FAIR TO GOOD IN THE WEST. RAIN SHOWERS AND MOUNTAIN SNOW SHOWERS WILL CONTINUE TONIGHT WITH A FEW STORMS THIS EVENING. PRECIPITATION WILL AGAIN FAVOR WEST AND CENTRAL AREAS. RH RECOVERIES WILL BE EXCELLENT. A GRADUAL DRYING AND WARMING TREND WILL BEGIN THIS WEEKEND AND CONTINUE EARLY NEXT WEEK. ISOLATED SHOWERS WILL FAVOR THE WESTERN AND CENTRAL MOUNTAINS SATURDAY...THEN IT WILL BE DRY AREA WIDE SUNDAY. WETTING RAINS WILL BE SCARCE SATURDAY...IF ANY AT ALL. TEMPERATURES WILL INCREASE 5 TO 10 DEGREES EACH DAY THIS WEEKEND WHILE MINIMUM RH VALUES PLUMMET...WITH MOSTLY TEENS ON SUNDAY ASIDE FROM THE 20S OVER THE HIGHER TERRAIN. VENT RATES WILL IMPROVE WITH THE ONLY POOR RATES IN THE NORTHEAST SATURDAY...THEN GOOD TO EXCELLENT SUNDAY. THE WARM AND DRY WEATHER WILL CONTINUE EARLY NEXT WEEK WITH THE FLOW ALOFT INCREASING OUT OF THE WEST. THIS WILL HELP PRODUCE STRONGER SURFACE WINDS ALONG WITH THE DEVELOPMENT OF A LEE SIDE TROUGH IN THE EAST. CRITICAL FIRE WEATHER CONDITIONS WILL BE APPROACHED ON MONDAY ACROSS EASTERN PORTIONS OF ZONE 106...THEN REACHED FOR A FEW HOURS ON TUESDAY. MAIN THREAT TUESDAY WILL BE FROM CLINES CORNERS TO SANTA ROSA. VENT RATES WILL BE GOOD TO EXCELLENT MONDAY AND TUESDAY. A DEEPENING SHORT WAVE TROUGH TO OUR NORTHWEST WEDNESDAY WILL DROP A BACK DOOR COLD FRONT INTO THE EAST WITH COOLER TEMPERATURES FOR ALL AREAS...ESPECIALLY THE EAST. THIS WILL ELIMINATE CRITICAL FIRE WEATHER CONCERNS AS MINIMUM RH VALUES RISE INTO THE 20S ACROSS THE EAST. SHOWERS WILL DEVELOP OVER THE WEST AND NORTH MOUNTAINS WEDNESDAY AND SPREAD ACROSS MUCH OF THE AREA THURSDAY INTO FRIDAY. TEMPERATURES WILL CONTINUE TO COOL TO BELOW NORMAL LEVELS WHILE RH VALUES INCREASE SHARPLY. CHJ && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
315 AM MDT FRI MAR 20 2015 .SYNOPSIS... RAIN CONTINUES THIS MORNING ACROSS PORTIONS OF CENTRAL AND WEST CENTRAL NEW MEXICO. THOUGH THIS ACTIVITY WILL DIMINISH LATER THIS MORNING...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON. COVERAGE WILL NOT BE AS WIDESPREAD AS YESTERDAY...NOR WILL AMOUNTS BE AS GREAT. NONETHELESS...PORTIONS OF WESTERN NEW MEXICO WILL BE FAVORED. ON SATURDAY...PRECIPITATION CHANCES WILL FAVOR SOUTH CENTRAL AND SOUTHEASTERN PORTIONS OF THE AREA...THOUGH SPOTTY HIGH TERRAIN STORMS WILL BE POSSIBLE ELSEWHERE. EARLY NEXT WEEK...DRY AND BREEZY CONDITIONS...MORE TYPICAL OF MARCH...ARE EXPECTED. && .DISCUSSION... RAIN IS PERSISTING THIS MORNING FROM JUST SOUTH OF THE JEMEZ MTNS...SOUTH-SOUTHWESTWARD TOWARD THE WEST CENTRAL AND SW MTNS. THIS AREA OF RAIN APPEARS TO BE WITHIN THE DEFORMATION ZONE OF THE UPPER LEVEL TROUGH...BUT AS THIS BECOMES MORE ILL-DEFINED...RAIN SHOULD SLOWLY DIMINISH THROUGH THE MORNING HOURS. FURTHER NORTH...A FEW SPRINKLES OR FLURRIES CONTINUE...BUT BY AND LARGE...PRECIPITATION HAS ENDED IN THIS AREA. THEREFORE...WILL CANCEL THE WINTER HIGHLIGHTS WITH THIS MORNINGS PACKAGE. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON...THOUGH THE BEST LIFT FROM THE UPPER LEVEL LOW WILL BE ACROSS SOUTHWEST PORTIONS OF THE CWA. MODELS CONTINUE TO TREND BACK QPF AMOUNTS ACROSS THE CENTRAL MTN CHAIN...THOUGH THE HRRR SUGGESTS SOME SCATTERED LIGHT POPCORN CONVECTION THIS AFTN. REGARDLESS...NOT LOOKING FOR PRECIPITATION COVERAGE TO BE AS WIDESPREAD AS YESTERDAY...AND THE BEST CHANCES FOR WETTING RAINS LOOK TO BE ACROSS THE SW MTNS. THE TROUGH/LOW WILL CONTINUE TO WEAKEN AS IT SHIFTS NORTHEASTWARD ON SATURDAY...CROSSING FAR SE NM IN THE AFTN. HOWEVER...MODELS ARE NOW SHOWING A BETTER CHANCE FOR PRECIP TO BULGE NORTHWARD INTO SC AND SE PORTIONS OF THE CWA. HAVE INCREASED POPS IN THESE AREAS AND TRENDED TEMPS DOWNWARD ACCORDINGLY. ELSEWHERE...SPOTTY SHOWERS OR A T-STORM MAY DEVELOP OVER THE HIGHER TERRAIN...BUT THE DRIER AIR MOVING IN WILL START TO TAKE ITS TOLL. BY SUNDAY...THE TROUGH WILL BE EAST OF NM AND MUCH DRIER AIR BENEATH A WEAK RIDGE WILL ELIMINATE PRECIPITATION CHANCES. STRENGTHENING WESTERLY FLOW ALOFT AND THE DEVELOPMENT OF A SURFACE LOW OVER SE CO WILL RESULT IN A DRY AND WINDY DAY ON MONDAY...WITH SIMILAR CONDITIONS ON TUESDAY. TEMPERATURES WILL WARM WELL ABOVE NORMAL...ESPECIALLY ACROSS THE EAST DUE TO COMPRESSIONAL WARMING. MODELS REMAIN AT ODDS REGARDING THE TIMING AND STRENGTH OF THE NEXT SYSTEM SOMETIME MID TO LATE WEEK. THE STRENGTH AND TIMING OF THE ASSOCIATED BACK DOOR COLD FRONT IS IN QUESTION AS WELL...WHICH WILL HAVE IMPACTS ON PRECIPITATION CHANCES. STAY TUNED. 34 && .FIRE WEATHER... MOIST ATMOSPHERE TO GRADUALLY DRY OUT THROUGH THE WEEKEND. EARLY NEXT WEEK WILL BE DRY AND WARM WITH INCREASING WINDS...CREATING THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS. STORM OVER BAJA CA WILL CONTINUE TO BRING WIDESPREAD SHOWERS TODAY FAVORING THE WEST AND CENTRAL AREAS. THERE WILL BE A FEW STORMS AS WELL. TEMPERATURES WILL BE MILDER IN THE NORTHEAST AND COOLER IN THE SOUTHEAST WITH NOT MUCH CHANGE ELSEWHERE. MINIMUM RH VALUES WILL BE MUCH LOWER IN THE NORTHEAST. VENT RATES WILL BE POOR IN THE EAST AND CENTRAL AREAS AND FAIR TO GOOD IN THE WEST. RAIN SHOWERS AND MOUNTAIN SNOW SHOWERS WILL CONTINUE TONIGHT WITH A FEW STORMS THIS EVENING. PRECIPITATION WILL AGAIN FAVOR WEST AND CENTRAL AREAS. RH RECOVERIES WILL BE EXCELLENT. A GRADUAL DRYING AND WARMING TREND WILL BEGIN THIS WEEKEND AND CONTINUE EARLY NEXT WEEK. ISOLATED SHOWERS WILL FAVOR THE WESTERN AND CENTRAL MOUNTAINS SATURDAY...THEN IT WILL BE DRY AREA WIDE SUNDAY. WETTING RAINS WILL BE SCARCE SATURDAY...IF ANY AT ALL. TEMPERATURES WILL INCREASE 5 TO 10 DEGREES EACH DAY THIS WEEKEND WHILE MINIMUM RH VALUES PLUMMET...WITH MOSTLY TEENS ON SUNDAY ASIDE FROM THE 20S OVER THE HIGHER TERRAIN. VENT RATES WILL IMPROVE WITH THE ONLY POOR RATES IN THE NORTHEAST SATURDAY...THEN GOOD TO EXCELLENT SUNDAY. THE WARM AND DRY WEATHER WILL CONTINUE EARLY NEXT WEEK WITH THE FLOW ALOFT INCREASING OUT OF THE WEST. THIS WILL HELP PRODUCE STRONGER SURFACE WINDS ALONG WITH THE DEVELOPMENT OF A LEE SIDE TROUGH IN THE EAST. CRITICAL FIRE WEATHER CONDITIONS WILL BE APPROACHED ON MONDAY ACROSS EASTERN PORTIONS OF ZONE 106...THEN REACHED FOR A FEW HOURS ON TUESDAY. MAIN THREAT TUESDAY WILL BE FROM CLINES CORNERS TO SANTA ROSA. VENT RATES WILL BE GOOD TO EXCELLENT MONDAY AND TUESDAY. A DEEPENING SHORT WAVE TROUGH TO OUR NORTHWEST WEDNESDAY WILL DROP A BACK DOOR COLD FRONT INTO THE EAST WITH COOLER TEMPERATURES FOR ALL AREAS...ESPECIALLY THE EAST. THIS WILL ELIMINATE CRITICAL FIRE WEATHER CONCERNS AS MINIMUM RH VALUES RISE INTO THE 20S ACROSS THE EAST. SHOWERS WILL DEVELOP OVER THE WEST AND NORTH MOUNTAINS WEDNESDAY AND SPREAD ACROSS MUCH OF THE AREA THURSDAY INTO FRIDAY. TEMPERATURES WILL CONTINUE TO COOL TO BELOW NORMAL LEVELS WHILE RH VALUES INCREASE SHARPLY. CHJ && .AVIATION... 06Z TAF CYCLE CURRENTLY IN THE THICK OF IT ACROSS CENTRAL AND EASTERN NM. RAIN WITH PATCHY FOG...AND HIGH TERRAIN SNOW...IS IMPACTING MUCH OF THE AREA. IFR CIGS/VSBYS MAINLY ALONG AND SOUTH OF I-40 OVER EASTERN NM WILL SLOWLY IMPROVE AROUND SUNRISE AS PRECIP EXITS THE AREA. THE BIG CHALLENGE WILL BE WHAT HAPPENS AROUND THE RIO GRANDE VALLEY AS A COLD FRONT IS INTERACTING WITH AN UPPER WAVE DRIFTING ACROSS THE REGION. CURRENTLY THE RADAR SHOWS WIDESPREAD RAIN AND SHORT- TERM MODEL GUIDANCE INDICATES THIS WILL CONTINUE THROUGH EARLY FRIDAY MORNING. GAP WINDS AROUND KABQ MAY FORCE IMPACTS FARTHER TO THE WEST HOWEVER STILL SOME MVFR CIGS ARE ON TAP THROUGH 15Z. AMOUNT OF FOG THAT DEVELOPS BEFORE SUNRISE WILL BE A CHALLENGE. CLEARING IS ANTICIPATED MOST AREAS BY LATE MORNING BEFORE ANOTHER ROUND OF SHOWERS/STORMS DEVELOPS OVER THE HIGH TERRAIN. GUYER && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 65 35 68 35 / 10 5 5 5 DULCE........................... 56 29 63 29 / 30 20 10 5 CUBA............................ 54 33 62 32 / 40 20 5 5 GALLUP.......................... 59 30 65 26 / 30 10 5 5 EL MORRO........................ 51 31 59 29 / 40 30 10 5 GRANTS.......................... 55 28 65 25 / 50 20 5 5 QUEMADO......................... 54 31 60 29 / 40 30 5 5 GLENWOOD........................ 66 39 70 39 / 30 20 5 5 CHAMA........................... 52 26 57 26 / 40 30 20 10 LOS ALAMOS...................... 51 36 60 38 / 40 20 20 10 PECOS........................... 50 34 60 36 / 30 20 10 5 CERRO/QUESTA.................... 51 26 59 27 / 30 20 10 5 RED RIVER....................... 44 24 51 25 / 40 30 20 10 ANGEL FIRE...................... 45 21 54 22 / 40 30 10 5 TAOS............................ 53 29 61 28 / 20 10 10 5 MORA............................ 49 31 59 31 / 30 20 10 5 ESPANOLA........................ 57 36 66 37 / 20 10 0 0 SANTA FE........................ 52 36 60 38 / 30 10 10 5 SANTA FE AIRPORT................ 55 34 64 35 / 30 10 5 5 ALBUQUERQUE FOOTHILLS........... 57 39 66 41 / 30 10 5 5 ALBUQUERQUE HEIGHTS............. 59 41 68 42 / 30 10 5 5 ALBUQUERQUE VALLEY.............. 61 38 69 38 / 30 10 5 5 ALBUQUERQUE WEST MESA........... 60 39 69 39 / 30 10 5 5 LOS LUNAS....................... 61 37 70 36 / 20 10 5 5 RIO RANCHO...................... 59 40 69 40 / 30 10 5 5 SOCORRO......................... 62 41 69 41 / 20 10 5 5 SANDIA PARK/CEDAR CREST......... 52 36 62 38 / 40 20 5 5 TIJERAS......................... 54 37 65 37 / 40 10 5 5 MORIARTY/ESTANCIA............... 55 29 64 29 / 30 10 5 5 CLINES CORNERS.................. 51 34 62 36 / 30 10 10 5 GRAN QUIVIRA.................... 55 36 64 37 / 30 10 5 5 CARRIZOZO....................... 59 40 65 40 / 20 10 5 5 RUIDOSO......................... 54 35 58 39 / 20 10 30 20 CAPULIN......................... 56 34 65 33 / 5 5 10 5 RATON........................... 57 31 67 31 / 10 5 5 5 SPRINGER........................ 57 32 66 33 / 10 5 5 5 LAS VEGAS....................... 51 31 63 33 / 30 10 5 5 CLAYTON......................... 60 40 70 42 / 5 0 5 5 ROY............................. 56 36 66 37 / 5 5 5 0 CONCHAS......................... 61 40 70 41 / 10 0 5 5 SANTA ROSA...................... 59 39 69 40 / 20 5 5 5 TUCUMCARI....................... 62 40 71 40 / 10 0 5 5 CLOVIS.......................... 60 41 65 41 / 5 0 10 10 PORTALES........................ 61 40 64 40 / 5 0 10 20 FORT SUMNER..................... 60 40 66 41 / 10 5 5 5 ROSWELL......................... 63 44 63 43 / 5 10 30 20 PICACHO......................... 56 40 61 41 / 10 10 20 10 ELK............................. 53 39 57 40 / 20 20 30 20 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 34
AREA FORECAST DISCUSSION
NWS BISMARCK ND
913 PM CDT SAT MAR 21 2015 .UPDATE... ISSUED AT 903 PM CDT SAT MAR 21 2015 RADAR SHOWS STEADY LIGHT SNOW IN ROLLA THAT WILL LAST FOR A FEW HOURS. THEN FOCUS WILL TURN TO THE WEST WHERE LOW LEVEL WARM ADVECTION AND FRONTAL BOUNDARY WILL FOCUS LIGHT RAIN THIS EVENING...WITH A WINTRY MIX OF RAIN...FREEZING RAIN OR SLEET AND SOME SNOW POSSIBLE AFTER MIDNIGHT. NEW NAM NOW PLACES MOST OF THE PRECIP IN CANADA. BUT BOTH NAM AND HRRR GENERATE A RAIN AREA SOUTHWEST TONIGHT. STILL MUCH UNCERTAINTY AT THIS LATE TIME. AM MORE COMFORTABLE WITH LESS FREEZING RAIN AND MORE RAIN THROUGH MIDNIGHT...WILL MONITOR AFTER MIDNIGHT BUT IF NAM IS RIGHT MOST OF PRECIP WILL BE NORTH IN CANADA. UPDATE ISSUED AT 646 PM CDT SAT MAR 21 2015 CLOUDS ARE INCREASING WEST ASSOCIATED WITH A SHORTWAVE TROUGH MOVING INTO THE NORTHERN PLAINS. WARM AIR ACROSS EASTERN MONTANA WILL MOVE OVER COOLER SURFACE AIR ACROSS WESTERN NORTH DAKOTA LATER TONIGHT. THIS COULD CREATE SOME FREEZING PRECIPITATION. SURFACE TEMPERATURES TO SAY THE LEAST WILL BE CRITICAL FOR THIS. AT 6 PM CROSBY RAWS IS 27 AND WILLISTON 41. WILL CONTINUE TO MONITOR. SO FAR CURRENT FORECAST LOOKS OK. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 320 PM CDT SAT MAR 21 2015 CURRENT SURFACE ANALYSIS PLACES LOW STRETCHING GENERALLY ALONG THE LEE SIDE OF THE ROCKIES WHILE HIGH STRETCHES FROM THE RED RIVER VALLEY UP INTO MANITOBA. UPPER LEVEL ANALYSIS PLACES RIDGE OVER EASTERN MONTANA UP INTO SASKATCHEWAN/ALBERTA WHILE DEEP LOW SPINS NEAR JAMES BAY BRINGING NORTHWEST FLOW TO OUR AREA. POTENT SHORT WAVE OVER THE NORTHWESTERN CONUS CONTINUES ITS EASTWARD PUSH. SOME LIGHT SNOW CONTINUES TO LINGER OVER THE NORTH CENTRAL PART OF THE STATE IN WEAK ISENTROPIC LIFT...THOUGH AREA WEBCAMS INDICATE VERY LITTLE IF ANY ACCUMULATION. FOR THE REST OF THIS AFTERNOON INTO TONIGHT...AFOREMENTIONED LIGHT SNOW OVER THE NORTH WILL CONTINUE TO SLOWLY DISSIPATE. OTHERWISE...MAIN CONCERN WILL BE THE SHORT WAVE OVER THE NORTHWESTERN CONUS MAKING ITS ADVANCE TOWARDS THE AREA. SHORT WAVE WILL PUSH ITS WAY OVER THE RIDGE...WITH PRECIPITATION DEVELOPING OVER THE WEST THIS EVENING AND SPREADING EAST OVERNIGHT. MOST LOCATIONS SHOULD SEE SNOW...OR POSSIBLY SOME RAIN OVER THE WEST WHERE TEMPERATURES WILL BE SLOWLY FALLING. LATER TONIGHT...FORECAST SOUNDINGS SUGGEST THE POSSIBILITY OF A LITTLE SLEET OF FREEZING RAIN MAINLY OVER THE FAR WEST SO HAVE ADDED A MENTION OF THAT. ON SUNDAY...SNOW WILL DIMINISH FROM WEST TO EAST AS SHORT WAVE CONTINUES ITS PROGRESSION THROUGH THE AREA. TOTAL SNOW AMOUNTS FROM THIS SYSTEM STILL LOOK TO BE THE HIGHEST MAINLY OVER NORTH CENTRAL NORTH DAKOTA INTO PARTS OF THE NORTHWEST. TEMPERATURES WILL REMAIN THE COOLEST MAINLY OVER THE CENTRAL PART OF THE STATE WHILE TO THE WEST EXPECT TEMPERATURES TO REBOUND AS SYSTEM MOVES TO THE EAST. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 320 PM CDT SAT MAR 21 2015 A POTENT SYSTEM COULD IMPACT THE REGION MIDWEEK. THE LATEST SUITE OF MODELS CONTINUES TO SLOW DOWN THE PROGRESSION OF OUR MID WEEK SYSTEM. PREVIOUS RUNS HAD PRECIPITATION BEGINNING MONDAY NIGHT WEST. HOWEVER...IT NOW APPEARS PRECIPITATION WILL BE DELAYED UNTIL TUESDAY. THERE IS STILL A LOT OF UNCERTAINTY IN THE EXACT TRACK OF THIS SYSTEM. OVER THE PAST TWO MODEL RUNS THE GFS HAS ONCE AGAIN COMPLETELY FLIP FLOPPED FROM A NORTHERN SOLUTION TO A SOUTHERN SOLUTION. THE ECMWF REMAINS FAIRLY CONSISTENT...WITH AN EVER SO SLIGHTLY FURTHER NORTH TRACK THAN THE 00 UTC RUN. THE GFS ENSEMBLE SPREAD IS RATHER WIDE...WITH THE CENTER OF THE LOW ANYWHERE FROM SOUTHERN CANADA TO NORTHERN IOWA. FOR THIS FORECAST...UTILIZED A BLEND OF THE OPERATIONAL MODELS. THIS LED TO GENERALLY LESSER AMOUNTS OF SNOW SOUTH OF HIGHWAY 2. IT APPEARS THAT MOST OF WESTERN AND CENTRAL NORTH DAKOTA WILL SEE TEMPERATURES WARM ENOUGH FOR ALL RAIN DURING THE MORNING AND AFTERNOON HOURS...AND THEN SEE A TRANSITION FROM NORTH TO SOUTH TO ALL SNOW OVERNIGHT. AT THIS TIME IT APPEARS THAT ONLY LOCATIONS NORTH OF HIGHWAY 2 WILL SEE BELOW FREEZING TEMPERATURES THROUGHOUT TUESDAY AND WEDNESDAY. TEMPERATURES WILL VARY GREATLY BASED ON THE EXACT TRACK OF THE LOW PRESSURE CENTER. THEREFORE...HEAVY SNOWFALL IS POSSIBLE WITH THIS SYSTEM AS STRONG FRONTOGENESIS...DEFORMATION BANDING...AND POTENTIAL TROWL SET UP ACROSS SOME PORTION OF NORTH DAKOTA...BUT AT THE SAME TIME IT COULD TURN OUT TO BE SIMPLY A HEAVY RAIN EVENT FOR WESTERN AND CENTRAL NORTH DAKOTA. THERE IS JUST TOO MUCH UNCERTAINTY AT THIS TIME TO NAIL DOWN SPECIFIC LOCATIONS AND SNOWFALL AMOUNTS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 646 PM CDT SAT MAR 21 2015 AT 6 PM CDT...A WARM FRONT EXTENDED ACROSS EASTERN MONTANA AND WILL BE THE FOCUS FOR A MIX OF FREEZING RAIN...RAIN AND SNOW OVER WESTERN NORTH DAKOTA TONIGHT. CURRENT VFR CONDITIONS WILL DETERIORATE TO IFR FROM KISN-KMOT AFTER 06Z. KDIK-KBIS-KJMS SHOULD FALL AS LOW AS MVFR ID CLOUDS AND SNOW. KISN-KDIK HAVE A POSSIBILITY FOR FREEZING RAIN BETWEEN 06Z-12Z. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...JJS LONG TERM...AJ AVIATION...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1253 PM CDT FRI MAR 20 2015 .UPDATE... ISSUED AT 1250 PM CDT FRI MAR 20 2015 SNOW QUICKLY SHIFTING EAST WITH LOWEST VSBY CURRENTLY ACROSS THE FAR EAST. WITH DIMINISHING SNOW AND RISING ROAD SURFACE TEMPERATURES WILL CANCEL THE ADVISORY. FARTHER EAST TEMPERATURES WARMER SO ALSO WILL SEE LESS ACCUMULATION. MADE SOME MINOR TEMPERATURE AND CLOUD COVER ADJUSTMENTS BUT NOTHING MAJOR. UPDATE ISSUED AT 1102 AM CDT FRI MAR 20 2015 HAVE ISSUED A WINTER WEATHER ADVISORY FOR 3-5 INCHES OF SNOW ALONG A NARROW LINE FROM CANDO TO EDMORE...PETERSBURG AND FOSSTON. WILL SEE A SHARP CUT OFF OF SNOW EITHER SIDE OF THIS LINE. UPDATE ISSUED AT 953 AM CDT FRI MAR 20 2015 ONLY CHANGES WERE TO SHRINK POPS ON EITHER SIDE OF NARROW SNOW BAND SHIFTING INTO PARTS OF NORTHERN VALLEY INTO NW MN. THIS IS SETTING UP TO BE A FAIRLY NARROW BAND AND WOULD NOT BE SURPRISED TO SEE SOME ISOLD 3-4 INCH AMOUNTS ACROSS THE NW FA. NO OTHER CHANGES AT THIS POINT. UPDATE ISSUED AT 645 AM CDT FRI MAR 20 2015 HEAVIER AREA OF SNOW HAS SET UP AS EXPECTED AND IS SET TO CONTINUE PROPAGATING EAST/SOUTHEAST. VIEWING WEBCAMS...IT HAS STARTED SNOWING LIGHTLY IN DEVILS LAKE AHEAD OF THE HEAVIER SNOWFALL...AND THE ROADS ARE WET. FURTHER WEST INTO THE HEAVIER SNOWFALL...ROADS ARE BECOMING COVERED WITH SNOW...WITH WHAT APPEARS TO BE AN INCH OR TWO OF ACCUMULATION (WHICH MAKES SENSE IF RATES ARE AN INCH PER HOUR). THE AREA OF HEAVIER SNOWFALL THAT WILL BE ABLE TO ACCUMULATE ON ROADWAYS APPEARS THAT IT WILL BE BRIEF (3 HOURS OR LESS)...WHICH MEANS GIVEN CURRENT SNOWFALL RATES OF AN INCH/HOUR THAT AREAS WITHIN THIS HEAVIER BAND WILL RECEIVE UP TO 3 INCHES OF SNOWFALL. SINCE THE SNOW IS MELTING ON ROADS WHERE THE SNOW IS LIGHTER...THIS SNOWFALL WILL NOT ADD TO THE OVERALL SNOWFALL. THUS...WILL NOT ISSUE A WINTER WEATHER ADVISORY AT THIS TIME. WILL CONTINUE TO MONITOR. THE MAIN IMPACT WILL BE 2-3 INCHES IN A SHORT DURATION OF MODERATE TO HEAVY SNOW (MAYBE UP TO 4 INCHES). THE LAST FEW RUNS OF THE HRRR...RAP...AND HOPWRF HAVE DECREASED OVERALL QPF...ALTHOUGH NOT SURE WHY. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 THE MAIN CONCERN WILL BE SNOWFALL AMOUNTS THIS MORNING INTO THE EARLY AFTERNOON HOURS. MODELS ARE INDICATING THE POTENTIAL FOR A BRIEF PERIOD OF HEAVY SNOW WITHIN A NARROW BAND. MID-LEVEL FRONTOGENESIS COMBINED WITH SYNOPTIC FORCING (UPPER JET SUPPORT) AND PWATS NEAR 0.4-0.5 INCHES SUPPORT A BANDED EVENT. HI-RES MODELS INDICATING AROUND 0.3 INCHES QPF WITHIN THIS NARROW BAND...WITH THE WRFARW4 AND WRFNMM4 INDICATING AROUND 0.5 INCHES QPF. HRRR AND RAP INDICATE THE LOCATION OF THIS BAND FROM LANGDON TO JUST NORTH OF GRAND FORKS AND BEMIDJI. OTHER GUIDANCE SHIFTS THIS BAND SLIGHTLY NORTH OR SOUTH. ROAD SFC TEMPS ARE NOW AROUND 32F...AND THE HEAVY NATURE OF THE SNOW SHOULD ALLOW ACCUMULATION ON ROAD SURFACES (EVEN IF IT FALLS DURING THE DAYTIME). WITH THAT SAID...THERE IS STILL UNCERTAINTY WITH THIS THINKING...ALONG WITH THE EXACT LOCATION OF THE SNOW BAND. FEEL RELATIVELY CONFIDENT THAT A PORTION OF THE REGION WILL REQUIRE A WINTER WX ADVISORY FOR THIS EVENT...BUT WITH THE LOCATION IN QUESTION WILL HOLD OFF UNTIL THE BAND ACTUALLY SETS UP. DID ISSUE AN SPS ATTEMPTING TO DESCRIBE THE SITUATION. MAX TEMPS WILL BE TRICKY TODAY GIVEN THE STRONG LOW LEVEL THERMAL GRADIENT. VALUES WILL RANGE FROM THE UPPER 20S NEAR THE INTERNATIONAL BORDER TO NEAR 60F CLOSER TO SOUTH DAKOTA. HIGH PRESSURE AND A MUCH COLDER AIRMASS INFLUENCES THE REGION TONIGHT INTO SATURDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 SATURDAY NIGHT-SUNDAY NIGHT...HIGH PRESSURE SHIFTS SLIGHTLY EAST AS A STRONGER SYSTEM ATTEMPTS TO PROPAGATE INTO THE REGION. KEPT THE HIGHER POPS ACROSS THE WESTERN FA AS THE PRECIP WILL LIKELY DIMINISH AS IT MOVES INTO THE DRIER AIRMASS. ACCUMULATING SNOW WILL BE POSSIBLE ACROSS A PORTION OF EASTERN NORTH DAKOTA. MONDAY-THURSDAY...THE LONG TERM COULD BRING A TEMPORARY RETURN OF WINTER CONDITIONS AS A LEE SIDE LOW DEVELOPS OVER THE NORTHERN CONUS ROCKIES AND EJECTS INTO THE NORTHERN PLAINS...TRACKING ACROSS SOUTH DAKOTA...SOUTHERN MINNESOTA AND INTO THE GREAT LAKES. THERE ARE TIMING DIFFERENCES WITH THE ECMWF BRINGING THE SFC LOW OUT OF NE WY A BIT SLOWER THAN THE GFS...THEN SPEEDING UP AND ENTERING THE GREAT LAKES AHEAD OF THE GFS. BOTH SYSTEMS TRACK THE LOW ALONG THE I 90 CORRIDOR AND BRING PRECIPITATION ACROSS NORTH DAKOTA AND NORTHERN MINNESOTA...MAINLY ON TUESDAY FOR OUR CWA. THERE WILL BE PERIODS OF A POTENTIAL RAIN SNOW MIX BUT THICKNESS VALUES FALL BY 06Z WEDNESDAY...AND ANY WRAP AROUND TUE NIGHT WILL LIKELY BE SNOW. MODELS ARE BRINGING AN ABUNDANCE OF PACIFIC MOISTURE WITH THIS SYSTEM...AND IT WILL BE A SYSTEM TO WATCH AS WE HAVE RECENTLY SEEN RECORD HIGHS AND MARCH LIKE WEATHER IS GRADUALLY RETURNING. THE LATTER HALF OF THE WEEK WILL BE DRY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1247 PM CDT FRI MAR 20 2015 NARROW BAND OF MODERATE SNOW IS EXITING THE NORTHERN VALLEY AT THIS TIME...CONDITIONS IMPROVING TO MVFR KGFK/KTVF THE NEXT HOUR OR TWO. ALL SNOW SHOULD BE CLEAR OF KBJI BY 21-24Z. ULTIMATELY LOOKING FOR A TRANSITION TO VFR BY LATE AFTERNOON FROM VALLEY WEST. GUSTY NORTH WINDS SHOULD ARRIVE IN WAKE OF SNOW...THEN SUBSIDE TOWARD EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...VOELKER SHORT TERM...TG LONG TERM...TG/SPEICHER AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1105 AM CDT FRI MAR 20 2015 .UPDATE... ISSUED AT 1102 AM CDT FRI MAR 20 2015 HAVE ISSUED A WINTER WEATHER ADVISORY FOR 3-5 INCHES OF SNOW ALONG A NARROW LINE FROM CANDO TO EDMORE...PETERSBURG AND FOSSTON. WILL SEE A SHARP CUT OFF OF SNOW EITHER SIDE OF THIS LINE. UPDATE ISSUED AT 953 AM CDT FRI MAR 20 2015 ONLY CHANGES WERE TO SHRINK POPS ON EITHER SIDE OF NARROW SNOW BAND SHIFTING INTO PARTS OF NORTHERN VALLEY INTO NW MN. THIS IS SETTING UP TO BE A FAIRLY NARROW BAND AND WOULD NOT BE SURPRISED TO SEE SOME ISOLD 3-4 INCH AMOUNTS ACROSS THE NW FA. NO OTHER CHANGES AT THIS POINT. UPDATE ISSUED AT 645 AM CDT FRI MAR 20 2015 HEAVIER AREA OF SNOW HAS SET UP AS EXPECTED AND IS SET TO CONTINUE PROPAGATING EAST/SOUTHEAST. VIEWING WEBCAMS...IT HAS STARTED SNOWING LIGHTLY IN DEVILS LAKE AHEAD OF THE HEAVIER SNOWFALL...AND THE ROADS ARE WET. FURTHER WEST INTO THE HEAVIER SNOWFALL...ROADS ARE BECOMING COVERED WITH SNOW...WITH WHAT APPEARS TO BE AN INCH OR TWO OF ACCUMULATION (WHICH MAKES SENSE IF RATES ARE AN INCH PER HOUR). THE AREA OF HEAVIER SNOWFALL THAT WILL BE ABLE TO ACCUMULATE ON ROADWAYS APPEARS THAT IT WILL BE BRIEF (3 HOURS OR LESS)...WHICH MEANS GIVEN CURRENT SNOWFALL RATES OF AN INCH/HOUR THAT AREAS WITHIN THIS HEAVIER BAND WILL RECEIVE UP TO 3 INCHES OF SNOWFALL. SINCE THE SNOW IS MELTING ON ROADS WHERE THE SNOW IS LIGHTER...THIS SNOWFALL WILL NOT ADD TO THE OVERALL SNOWFALL. THUS...WILL NOT ISSUE A WINTER WEATHER ADVISORY AT THIS TIME. WILL CONTINUE TO MONITOR. THE MAIN IMPACT WILL BE 2-3 INCHES IN A SHORT DURATION OF MODERATE TO HEAVY SNOW (MAYBE UP TO 4 INCHES). THE LAST FEW RUNS OF THE HRRR...RAP...AND HOPWRF HAVE DECREASED OVERALL QPF...ALTHOUGH NOT SURE WHY. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 THE MAIN CONCERN WILL BE SNOWFALL AMOUNTS THIS MORNING INTO THE EARLY AFTERNOON HOURS. MODELS ARE INDICATING THE POTENTIAL FOR A BRIEF PERIOD OF HEAVY SNOW WITHIN A NARROW BAND. MID-LEVEL FRONTOGENESIS COMBINED WITH SYNOPTIC FORCING (UPPER JET SUPPORT) AND PWATS NEAR 0.4-0.5 INCHES SUPPORT A BANDED EVENT. HI-RES MODELS INDICATING AROUND 0.3 INCHES QPF WITHIN THIS NARROW BAND...WITH THE WRFARW4 AND WRFNMM4 INDICATING AROUND 0.5 INCHES QPF. HRRR AND RAP INDICATE THE LOCATION OF THIS BAND FROM LANGDON TO JUST NORTH OF GRAND FORKS AND BEMIDJI. OTHER GUIDANCE SHIFTS THIS BAND SLIGHTLY NORTH OR SOUTH. ROAD SFC TEMPS ARE NOW AROUND 32F...AND THE HEAVY NATURE OF THE SNOW SHOULD ALLOW ACCUMULATION ON ROAD SURFACES (EVEN IF IT FALLS DURING THE DAYTIME). WITH THAT SAID...THERE IS STILL UNCERTAINTY WITH THIS THINKING...ALONG WITH THE EXACT LOCATION OF THE SNOW BAND. FEEL RELATIVELY CONFIDENT THAT A PORTION OF THE REGION WILL REQUIRE A WINTER WX ADVISORY FOR THIS EVENT...BUT WITH THE LOCATION IN QUESTION WILL HOLD OFF UNTIL THE BAND ACTUALLY SETS UP. DID ISSUE AN SPS ATTEMPTING TO DESCRIBE THE SITUATION. MAX TEMPS WILL BE TRICKY TODAY GIVEN THE STRONG LOW LEVEL THERMAL GRADIENT. VALUES WILL RANGE FROM THE UPPER 20S NEAR THE INTERNATIONAL BORDER TO NEAR 60F CLOSER TO SOUTH DAKOTA. HIGH PRESSURE AND A MUCH COLDER AIRMASS INFLUENCES THE REGION TONIGHT INTO SATURDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 SATURDAY NIGHT-SUNDAY NIGHT...HIGH PRESSURE SHIFTS SLIGHTLY EAST AS A STRONGER SYSTEM ATTEMPTS TO PROPAGATE INTO THE REGION. KEPT THE HIGHER POPS ACROSS THE WESTERN FA AS THE PRECIP WILL LIKELY DIMINISH AS IT MOVES INTO THE DRIER AIRMASS. ACCUMULATING SNOW WILL BE POSSIBLE ACROSS A PORTION OF EASTERN NORTH DAKOTA. MONDAY-THURSDAY...THE LONG TERM COULD BRING A TEMPORARY RETURN OF WINTER CONDITIONS AS A LEE SIDE LOW DEVELOPS OVER THE NORTHERN CONUS ROCKIES AND EJECTS INTO THE NORTHERN PLAINS...TRACKING ACROSS SOUTH DAKOTA...SOUTHERN MINNESOTA AND INTO THE GREAT LAKES. THERE ARE TIMING DIFFERENCES WITH THE ECMWF BRINGING THE SFC LOW OUT OF NE WY A BIT SLOWER THAN THE GFS...THEN SPEEDING UP AND ENTERING THE GREAT LAKES AHEAD OF THE GFS. BOTH SYSTEMS TRACK THE LOW ALONG THE I 90 CORRIDOR AND BRING PRECIPITATION ACROSS NORTH DAKOTA AND NORTHERN MINNESOTA...MAINLY ON TUESDAY FOR OUR CWA. THERE WILL BE PERIODS OF A POTENTIAL RAIN SNOW MIX BUT THICKNESS VALUES FALL BY 06Z WEDNESDAY...AND ANY WRAP AROUND TUE NIGHT WILL LIKELY BE SNOW. MODELS ARE BRINGING AN ABUNDANCE OF PACIFIC MOISTURE WITH THIS SYSTEM...AND IT WILL BE A SYSTEM TO WATCH AS WE HAVE RECENTLY SEEN RECORD HIGHS AND MARCH LIKE WEATHER IS GRADUALLY RETURNING. THE LATTER HALF OF THE WEEK WILL BE DRY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 645 AM CDT FRI MAR 20 2015 BAND OF SNOW AND LIFR/IFR CONDITIONS WILL AFFECT KDVL...KGFK...KTVF...AND KBJI THIS MORNING OR AFTERNOON FOR A 2-5 HOUR PERIOD. KFAR WILL BE ON THE SOUTHERN EDGE OF THE HEAVIER PRECIP...BUT COULD BRIEFLY BE AFFECTED. AFTER BREEZY NORTHERLY WINDS THIS AFTERNOON...CONDITIONS WILL IMPROVE THIS EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WINTER WEATHER ADVISORY UNTIL 3 PM CDT THIS AFTERNOON FOR NDZ006- 015-016-026-027-054. MN...WINTER WEATHER ADVISORY UNTIL 3 PM CDT THIS AFTERNOON FOR MNZ001. && $$ UPDATE...VOELKER SHORT TERM...TG LONG TERM...TG/SPEICHER AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
957 AM CDT FRI MAR 20 2015 .UPDATE... ISSUED AT 953 AM CDT FRI MAR 20 2015 ONLY CHANGES WERE TO SHRINK POPS ON EITHER SIDE OF NARROW SNOW BAND SHIFTING INTO PARTS OF NORTHERN VALLEY INTO NW MN. THIS IS SETTING UP TO BE A FAIRLY NARROW BAND AND WOULD NOT BE SURPRISED TO SEE SOME ISOLD 3-4 INCH AMOUNTS ACROSS THE NW FA. NO OTHER CHANGES AT THIS POINT. UPDATE ISSUED AT 645 AM CDT FRI MAR 20 2015 HEAVIER AREA OF SNOW HAS SET UP AS EXPECTED AND IS SET TO CONTINUE PROPAGATING EAST/SOUTHEAST. VIEWING WEBCAMS...IT HAS STARTED SNOWING LIGHTLY IN DEVILS LAKE AHEAD OF THE HEAVIER SNOWFALL...AND THE ROADS ARE WET. FURTHER WEST INTO THE HEAVIER SNOWFALL...ROADS ARE BECOMING COVERED WITH SNOW...WITH WHAT APPEARS TO BE AN INCH OR TWO OF ACCUMULATION (WHICH MAKES SENSE IF RATES ARE AN INCH PER HOUR). THE AREA OF HEAVIER SNOWFALL THAT WILL BE ABLE TO ACCUMULATE ON ROADWAYS APPEARS THAT IT WILL BE BRIEF (3 HOURS OR LESS)...WHICH MEANS GIVEN CURRENT SNOWFALL RATES OF AN INCH/HOUR THAT AREAS WITHIN THIS HEAVIER BAND WILL RECEIVE UP TO 3 INCHES OF SNOWFALL. SINCE THE SNOW IS MELTING ON ROADS WHERE THE SNOW IS LIGHTER...THIS SNOWFALL WILL NOT ADD TO THE OVERALL SNOWFALL. THUS...WILL NOT ISSUE A WINTER WEATHER ADVISORY AT THIS TIME. WILL CONTINUE TO MONITOR. THE MAIN IMPACT WILL BE 2-3 INCHES IN A SHORT DURATION OF MODERATE TO HEAVY SNOW (MAYBE UP TO 4 INCHES). THE LAST FEW RUNS OF THE HRRR...RAP...AND HOPWRF HAVE DECREASED OVERALL QPF...ALTHOUGH NOT SURE WHY. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 THE MAIN CONCERN WILL BE SNOWFALL AMOUNTS THIS MORNING INTO THE EARLY AFTERNOON HOURS. MODELS ARE INDICATING THE POTENTIAL FOR A BRIEF PERIOD OF HEAVY SNOW WITHIN A NARROW BAND. MID-LEVEL FRONTOGENESIS COMBINED WITH SYNOPTIC FORCING (UPPER JET SUPPORT) AND PWATS NEAR 0.4-0.5 INCHES SUPPORT A BANDED EVENT. HI-RES MODELS INDICATING AROUND 0.3 INCHES QPF WITHIN THIS NARROW BAND...WITH THE WRFARW4 AND WRFNMM4 INDICATING AROUND 0.5 INCHES QPF. HRRR AND RAP INDICATE THE LOCATION OF THIS BAND FROM LANGDON TO JUST NORTH OF GRAND FORKS AND BEMIDJI. OTHER GUIDANCE SHIFTS THIS BAND SLIGHTLY NORTH OR SOUTH. ROAD SFC TEMPS ARE NOW AROUND 32F...AND THE HEAVY NATURE OF THE SNOW SHOULD ALLOW ACCUMULATION ON ROAD SURFACES (EVEN IF IT FALLS DURING THE DAYTIME). WITH THAT SAID...THERE IS STILL UNCERTAINTY WITH THIS THINKING...ALONG WITH THE EXACT LOCATION OF THE SNOW BAND. FEEL RELATIVELY CONFIDENT THAT A PORTION OF THE REGION WILL REQUIRE A WINTER WX ADVISORY FOR THIS EVENT...BUT WITH THE LOCATION IN QUESTION WILL HOLD OFF UNTIL THE BAND ACTUALLY SETS UP. DID ISSUE AN SPS ATTEMPTING TO DESCRIBE THE SITUATION. MAX TEMPS WILL BE TRICKY TODAY GIVEN THE STRONG LOW LEVEL THERMAL GRADIENT. VALUES WILL RANGE FROM THE UPPER 20S NEAR THE INTERNATIONAL BORDER TO NEAR 60F CLOSER TO SOUTH DAKOTA. HIGH PRESSURE AND A MUCH COLDER AIRMASS INFLUENCES THE REGION TONIGHT INTO SATURDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 SATURDAY NIGHT-SUNDAY NIGHT...HIGH PRESSURE SHIFTS SLIGHTLY EAST AS A STRONGER SYSTEM ATTEMPTS TO PROPAGATE INTO THE REGION. KEPT THE HIGHER POPS ACROSS THE WESTERN FA AS THE PRECIP WILL LIKELY DIMINISH AS IT MOVES INTO THE DRIER AIRMASS. ACCUMULATING SNOW WILL BE POSSIBLE ACROSS A PORTION OF EASTERN NORTH DAKOTA. MONDAY-THURSDAY...THE LONG TERM COULD BRING A TEMPORARY RETURN OF WINTER CONDITIONS AS A LEE SIDE LOW DEVELOPS OVER THE NORTHERN CONUS ROCKIES AND EJECTS INTO THE NORTHERN PLAINS...TRACKING ACROSS SOUTH DAKOTA...SOUTHERN MINNESOTA AND INTO THE GREAT LAKES. THERE ARE TIMING DIFFERENCES WITH THE ECMWF BRINGING THE SFC LOW OUT OF NE WY A BIT SLOWER THAN THE GFS...THEN SPEEDING UP AND ENTERING THE GREAT LAKES AHEAD OF THE GFS. BOTH SYSTEMS TRACK THE LOW ALONG THE I 90 CORRIDOR AND BRING PRECIPITATION ACROSS NORTH DAKOTA AND NORTHERN MINNESOTA...MAINLY ON TUESDAY FOR OUR CWA. THERE WILL BE PERIODS OF A POTENTIAL RAIN SNOW MIX BUT THICKNESS VALUES FALL BY 06Z WEDNESDAY...AND ANY WRAP AROUND TUE NIGHT WILL LIKELY BE SNOW. MODELS ARE BRINGING AN ABUNDANCE OF PACIFIC MOISTURE WITH THIS SYSTEM...AND IT WILL BE A SYSTEM TO WATCH AS WE HAVE RECENTLY SEEN RECORD HIGHS AND MARCH LIKE WEATHER IS GRADUALLY RETURNING. THE LATTER HALF OF THE WEEK WILL BE DRY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 645 AM CDT FRI MAR 20 2015 BAND OF SNOW AND LIFR/IFR CONDITIONS WILL AFFECT KDVL...KGFK...KTVF...AND KBJI THIS MORNING OR AFTERNOON FOR A 2-5 HOUR PERIOD. KFAR WILL BE ON THE SOUTHERN EDGE OF THE HEAVIER PRECIP...BUT COULD BRIEFLY BE AFFECTED. AFTER BREEZY NORTHERLY WINDS THIS AFTERNOON...CONDITIONS WILL IMPROVE THIS EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...VOELKER SHORT TERM...TG LONG TERM...TG/SPEICHER AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
645 AM CDT FRI MAR 20 2015 .UPDATE... ISSUED AT 645 AM CDT FRI MAR 20 2015 HEAVIER AREA OF SNOW HAS SET UP AS EXPECTED AND IS SET TO CONTINUE PROPAGATING EAST/SOUTHEAST. VIEWING WEBCAMS...IT HAS STARTED SNOWING LIGHTLY IN DEVILS LAKE AHEAD OF THE HEAVIER SNOWFALL...AND THE ROADS ARE WET. FURTHER WEST INTO THE HEAVIER SNOWFALL...ROADS ARE BECOMING COVERED WITH SNOW...WITH WHAT APPEARS TO BE AN INCH OR TWO OF ACCUMULATION (WHICH MAKES SENSE IF RATES ARE AN INCH PER HOUR). THE AREA OF HEAVIER SNOWFALL THAT WILL BE ABLE TO ACCUMULATE ON ROADWAYS APPEARS THAT IT WILL BE BRIEF (3 HOURS OR LESS)...WHICH MEANS GIVEN CURRENT SNOWFALL RATES OF AN INCH/HOUR THAT AREAS WITHIN THIS HEAVIER BAND WILL RECEIVE UP TO 3 INCHES OF SNOWFALL. SINCE THE SNOW IS MELTING ON ROADS WHERE THE SNOW IS LIGHTER...THIS SNOWFALL WILL NOT ADD TO THE OVERALL SNOWFALL. THUS...WILL NOT ISSUE A WINTER WEATHER ADVISORY AT THIS TIME. WILL CONTINUE TO MONITOR. THE MAIN IMPACT WILL BE 2-3 INCHES IN A SHORT DURATION OF MODERATE TO HEAVY SNOW (MAYBE UP TO 4 INCHES). THE LAST FEW RUNS OF THE HRRR...RAP...AND HOPWRF HAVE DECREASED OVERALL QPF...ALTHOUGH NOT SURE WHY. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 THE MAIN CONCERN WILL BE SNOWFALL AMOUNTS THIS MORNING INTO THE EARLY AFTERNOON HOURS. MODELS ARE INDICATING THE POTENTIAL FOR A BRIEF PERIOD OF HEAVY SNOW WITHIN A NARROW BAND. MID-LEVEL FRONTOGENESIS COMBINED WITH SYNOPTIC FORCING (UPPER JET SUPPORT) AND PWATS NEAR 0.4-0.5 INCHES SUPPORT A BANDED EVENT. HI-RES MODELS INDICATING AROUND 0.3 INCHES QPF WITHIN THIS NARROW BAND...WITH THE WRFARW4 AND WRFNMM4 INDICATING AROUND 0.5 INCHES QPF. HRRR AND RAP INDICATE THE LOCATION OF THIS BAND FROM LANGDON TO JUST NORTH OF GRAND FORKS AND BEMIDJI. OTHER GUIDANCE SHIFTS THIS BAND SLIGHTLY NORTH OR SOUTH. ROAD SFC TEMPS ARE NOW AROUND 32F...AND THE HEAVY NATURE OF THE SNOW SHOULD ALLOW ACCUMULATION ON ROAD SURFACES (EVEN IF IT FALLS DURING THE DAYTIME). WITH THAT SAID...THERE IS STILL UNCERTAINTY WITH THIS THINKING...ALONG WITH THE EXACT LOCATION OF THE SNOW BAND. FEEL RELATIVELY CONFIDENT THAT A PORTION OF THE REGION WILL REQUIRE A WINTER WX ADVISORY FOR THIS EVENT...BUT WITH THE LOCATION IN QUESTION WILL HOLD OFF UNTIL THE BAND ACTUALLY SETS UP. DID ISSUE AN SPS ATTEMPTING TO DESCRIBE THE SITUATION. MAX TEMPS WILL BE TRICKY TODAY GIVEN THE STRONG LOW LEVEL THERMAL GRADIENT. VALUES WILL RANGE FROM THE UPPER 20S NEAR THE INTERNATIONAL BORDER TO NEAR 60F CLOSER TO SOUTH DAKOTA. HIGH PRESSURE AND A MUCH COLDER AIRMASS INFLUENCES THE REGION TONIGHT INTO SATURDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 SATURDAY NIGHT-SUNDAY NIGHT...HIGH PRESSURE SHIFTS SLIGHTLY EAST AS A STRONGER SYSTEM ATTEMPTS TO PROPAGATE INTO THE REGION. KEPT THE HIGHER POPS ACROSS THE WESTERN FA AS THE PRECIP WILL LIKELY DIMINISH AS IT MOVES INTO THE DRIER AIRMASS. ACCUMULATING SNOW WILL BE POSSIBLE ACROSS A PORTION OF EASTERN NORTH DAKOTA. MONDAY-THURSDAY...THE LONG TERM COULD BRING A TEMPORARY RETURN OF WINTER CONDITIONS AS A LEE SIDE LOW DEVELOPS OVER THE NORTHERN CONUS ROCKIES AND EJECTS INTO THE NORTHERN PLAINS...TRACKING ACROSS SOUTH DAKOTA...SOUTHERN MINNESOTA AND INTO THE GREAT LAKES. THERE ARE TIMING DIFFERENCES WITH THE ECMWF BRINGING THE SFC LOW OUT OF NE WY A BIT SLOWER THAN THE GFS...THEN SPEEDING UP AND ENTERING THE GREAT LAKES AHEAD OF THE GFS. BOTH SYSTEMS TRACK THE LOW ALONG THE I 90 CORRIDOR AND BRING PRECIPITATION ACROSS NORTH DAKOTA AND NORTHERN MINNESOTA...MAINLY ON TUESDAY FOR OUR CWA. THERE WILL BE PERIODS OF A POTENTIAL RAIN SNOW MIX BUT THICKNESS VALUES FALL BY 06Z WEDNESDAY...AND ANY WRAP AROUND TUE NIGHT WILL LIKELY BE SNOW. MODELS ARE BRINGING AN ABUNDANCE OF PACIFIC MOISTURE WITH THIS SYSTEM...AND IT WILL BE A SYSTEM TO WATCH AS WE HAVE RECENTLY SEEN RECORD HIGHS AND MARCH LIKE WEATHER IS GRADUALLY RETURNING. THE LATTER HALF OF THE WEEK WILL BE DRY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 645 AM CDT FRI MAR 20 2015 BAND OF SNOW AND LIFR/IFR CONDITIONS WILL AFFECT KDVL...KGFK...KTVF...AND KBJI THIS MORNING OR AFTERNOON FOR A 2-5 HOUR PERIOD. KFAR WILL BE ON THE SOUTHERN EDGE OF THE HEAVIER PRECIP...BUT COULD BRIEFLY BE AFFECTED. AFTER BREEZY NORTHERLY WINDS THIS AFTERNOON...CONDITIONS WILL IMPROVE THIS EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...TG SHORT TERM...TG LONG TERM...TG/SPEICHER AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
300 AM CDT FRI MAR 20 2015 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 THE MAIN CONCERN WILL BE SNOWFALL AMOUNTS THIS MORNING INTO THE EARLY AFTERNOON HOURS. MODELS ARE INDICATING THE POTENTIAL FOR A BRIEF PERIOD OF HEAVY SNOW WITHIN A NARROW BAND. MID-LEVEL FRONTOGENESIS COMBINED WITH SYNOPTIC FORCING (UPPER JET SUPPORT) AND PWATS NEAR 0.4-0.5 INCHES SUPPORT A BANDED EVENT. HI-RES MODELS INDICATING AROUND 0.3 INCHES QPF WITHIN THIS NARROW BAND...WITH THE WRFARW4 AND WRFNMM4 INDICATING AROUND 0.5 INCHES QPF. HRRR AND RAP INDICATE THE LOCATION OF THIS BAND FROM LANGDON TO JUST NORTH OF GRAND FORKS AND BEMIDJI. OTHER GUIDANCE SHIFTS THIS BAND SLIGHTLY NORTH OR SOUTH. ROAD SFC TEMPS ARE NOW AROUND 32F...AND THE HEAVY NATURE OF THE SNOW SHOULD ALLOW ACCUMULATION ON ROAD SURFACES (EVEN IF IT FALLS DURING THE DAYTIME). WITH THAT SAID...THERE IS STILL UNCERTAINTY WITH THIS THINKING...ALONG WITH THE EXACT LOCATION OF THE SNOW BAND. FEEL RELATIVELY CONFIDENT THAT A PORTION OF THE REGION WILL REQUIRE A WINTER WX ADVISORY FOR THIS EVENT...BUT WITH THE LOCATION IN QUESTION WILL HOLD OFF UNTIL THE BAND ACTUALLY SETS UP. DID ISSUE AN SPS ATTEMPTING TO DESCRIBE THE SITUATION. MAX TEMPS WILL BE TRICKY TODAY GIVEN THE STRONG LOW LEVEL THERMAL GRADIENT. VALUES WILL RANGE FROM THE UPPER 20S NEAR THE INTERNATIONAL BORDER TO NEAR 60F CLOSER TO SOUTH DAKOTA. HIGH PRESSURE AND A MUCH COLDER AIRMASS INFLUENCES THE REGION TONIGHT INTO SATURDAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 300 AM CDT FRI MAR 20 2015 SATURDAY NIGHT-SUNDAY NIGHT...HIGH PRESSURE SHIFTS SLIGHTLY EAST AS A STRONGER SYSTEM ATTEMPTS TO PROPAGATE INTO THE REGION. KEPT THE HIGHER POPS ACROSS THE WESTERN FA AS THE PRECIP WILL LIKELY DIMINISH AS IT MOVES INTO THE DRIER AIRMASS. ACCUMULATING SNOW WILL BE POSSIBLE ACROSS A PORTION OF EASTERN NORTH DAKOTA. MONDAY-THURSDAY...THE LONG TERM COULD BRING A TEMPORARY RETURN OF WINTER CONDITIONS AS A LEE SIDE LOW DEVELOPS OVER THE NORTHERN CONUS ROCKIES AND EJECTS INTO THE NORTHERN PLAINS...TRACKING ACROSS SOUTH DAKOTA...SOUTHERN MINNESOTA AND INTO THE GREAT LAKES. THERE ARE TIMING DIFFERENCES WITH THE ECMWF BRINGING THE SFC LOW OUT OF NE WY A BIT SLOWER THAN THE GFS...THEN SPEEDING UP AND ENTERING THE GREAT LAKES AHEAD OF THE GFS. BOTH SYSTEMS TRACK THE LOW ALONG THE I 90 CORRIDOR AND BRING PRECIPITATION ACROSS NORTH DAKOTA AND NORTHERN MINNESOTA...MAINLY ON TUESDAY FOR OUR CWA. THERE WILL BE PERIODS OF A POTENTIAL RAIN SNOW MIX BUT THICKNESS VALUES FALL BY 06Z WEDNESDAY...AND ANY WRAP AROUND TUE NIGHT WILL LIKELY BE SNOW. MODELS ARE BRINGING AN ABUNDANCE OF PACIFIC MOISTURE WITH THIS SYSTEM...AND IT WILL BE A SYSTEM TO WATCH AS WE HAVE RECENTLY SEEN RECORD HIGHS AND MARCH LIKE WEATHER IS GRADUALLY RETURNING. THE LATTER HALF OF THE WEEK WILL BE DRY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1137 PM CDT THU MAR 19 2015 TRIED TO GIVE BEST IDEAS OF TIMING ON THE SNOW BAND THAT WILL MOVE ACROSS THE KDVL/KGFK/KTVF/KBJI AREAS FRIDAY. KFAR SHOULD BE MORE ON THE SOUTHERN FRINGE OF THE SNOW BAND SO THEY SHOULD AVOID THE LOWER VSBYS AND CLOUDS THAT WILL HIT THE OTHER 4 SITES. LOOKS LIKE IT WILL SNOW PRETTY HEAVILY RIGHT ALONG THE HIGHWAY 2 CORRIDOR SO WENT WITH LOW VSBYS/CLOUDS AS A FIRST GUESS. LATEST MODELS ARE SHOWING POTENTIAL FOR 1-4 INCHES OF SNOW HERE. THINKING IT WILL BE A 4 HOUR WINDOW OR SO OF HEAVY SNOW BEFORE IT QUICKLY BEGINS TO IMPROVE AGAIN. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...TG LONG TERM...TG/SPEICHER AVIATION...GODON
AREA FORECAST DISCUSSION
NWS BISMARCK ND
100 AM CDT FRI MAR 20 2015 .UPDATE... ISSUED AT 100 AM CDT FRI MAR 20 2015 EMBEDDED MID LEVEL SHORT WAVE TROUGH AND ASSOCIATED SURFACE LOW PRESSURE WILL BRING A SWATH OF PRECIPITATION TO THE NORTHERN HALF OF THE STATE OVERNIGHT INTO FRIDAY MORNING. ADJUSTED POPS BASED ON LATEST REGIONAL RADAR AND NEAR TERM HIGH RES MODEL OUTPUT. BASICALLY INCREASED TO 100 POPS ACROSS MY NORTH. MAY SEE SPORADIC SLEET OR EVEN FREEZING RAIN DEPENDING ON WHAT SURFACE TEMPERATURES DO FOR THE REST OF THE AM HOURS...SO OPTED TO THROW THIS MENTION INTO THE GRIDDED FORECAST. AS THE LOW TRACKS OFF TO OUR SOUTH AND EAST FRIDAY...WRAP AROUND MOISTURE WILL BRING A CHANCE FOR SOME LIGHT SNOW EARLY TO MID AFTERNOON ACROSS THE NORTH BEHIND A SFC COLD FRONT. UPDATE ISSUED AT 934 PM CDT THU MAR 19 2015 CLOUDS HAVE CLEARED FROM THE JAMES RIVER VALLEY. MEANWHILE THE NEXT SYSTEM IS SPREADING CLOUDS INTO THE NORTHWEST. WILL SEE SOME LIGHT SNOW DEVELOP AFTER MIDNIGHT. CURRENT FORECAST TENDS LOOK OK. UPDATE ISSUED AT 627 PM CDT THU MAR 19 2015 A GOOD WESTERLY DOWN SLOPE WIND HAS CONTRIBUTED TO A RAPID DISSIPATION OF THE CLOUD COVER. IT IS NOW CLEAR ALL THE WAY TO THE JAMES RIVER VALLEY AND THAT WILL CLEAR THIS EVENING. CLOUDS ALSO KEEPING LATE AFTERNOON/EARLY EVENING TEMPERATURES COOL ACROSS THE JAMES RIVER VALLEY. AS WINDS SHIFT TO THE NORTHWEST AND CLOUDS CLEAR MIXING WILL INCREASE AND SHOULD SEE THE HIGH TEMPERATURES FOR THE DAY THIS EVENING. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 257 PM CDT THU MAR 19 2015 SNOW ACROSS NORTHERN NORTH DAKOTA TONIGHT HIGHLIGHTS THE SHORT TERM FORECAST. THE LOW STRATUS FIELD ACROSS WESTERN AND CENTRAL NORTH DAKOTA WILL CONTINUE TO ERODE FROM WEST TO EAST THROUGH THE REMAINDER OF THE AFTERNOON AND EARLY EVENING GIVEN THE LATEST VISIBLE SATELLITE TRENDS AND 16-18 UTC HRRR ITERATIONS. THEREAFTER...A RAPIDLY PROPAGATING CLIPPER SYSTEM WILL ENTER NORTHWESTERN NORTH DAKOTA EARLY FRIDAY MORNING...EXITING INTO NORTH CENTRAL SOUTH DAKOTA BY 18 UTC. A BAND OF LIGHT TO MODERATE SNOW WILL DEVELOP NORTH OF THE SURFACE LOW TRACK ACROSS NORTH CENTRAL NORTH DAKOTA IN CONJUNCTION WITH THE ARRIVAL OF A COLD FRONT INTO NORTHERN NORTH DAKOTA. THE GREATEST SNOWFALL TOTALS OF TWO TO THREE INCHES ARE FORECAST FOR THE TURTLE MOUNTAINS...QUICKLY DECREASING TO THE SOUTH AND WEST. IN THE WARM SECTOR OF THE CLIPPER ACROSS SOUTHERN NORTH DAKOTA...HIGHS IN THE LOWER 60S ARE POSSIBLE...NEAR THE WARMER EDGE OF THE 12 UTC SUITE...GIVEN THE BIAS TO BE TOO COLD SO FAR IN A WELL MIXED ENVIRONMENT WITH GOOD INSOLATION THIS MONTH. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 320 PM CDT THU MAR 19 2015 SEVERAL PERIODS OF ACCUMULATING SNOW ARE POSSIBLE SATURDAY THROUGH WEDNESDAY. AN ACTIVE WEATHER PATTERN IS SETTING UP FOR WESTERN AND CENTRAL NORTH DAKOTA THIS WEEKEND THROUGH MID-WEEK. THE FIRST STORM...AND POTENTIAL FOR WIDESPREAD ACCUMULATING SNOW... WILL ARRIVE LATE SATURDAY AFTERNOON AND REMAIN THROUGH LATE SUNDAY NIGHT. UPSLOPE FLOW...POTENT LEE CYCLOGENESIS AND FAVORABLE UPPER LEVEL JET DYNAMICS (RIGHT ENTRANCE REGION OF A AN 80 KNOT JET) COULD PRODUCE WIDESPREAD MODERATE SNOWFALL. THE MAIN AXIS OF FRONTOGENESIS AND LIFT APPEARS TO BE SETTING UP MAINLY NORTH AND EAST OF THE MISSOURI RIVER. THE NEXT...AND POTENTIALLY STRONGER...STORM SYSTEM SHOULD IMPACT THE REGION MONDAY NIGHT THROUGH WEDNESDAY AFTERNOON. THERE IS SOME UNCERTAINTY IN THE EXACT TRACK OF THIS SYSTEM. THE 12 UTC GFS HAS BEEN CONSISTENT IN SHOWING THE DEFORMATION ZONE ACROSS SOUTHERN NORTH DAKOTA...WHILE THE 12 UTC ECMWF IS STILL SHOWING A FURTHER NORTH SOLUTION. IT IS IMPORTANT TO NOTE THAT THE LATEST ECMWF RUN IS TRENDING FURTHER SOUTH COMPARED TO PREVIOUS RUNS. SO IT DOES APPEAR THAT AT LEAST SOME PORTION OF NORTH DAKOTA WILL BE IMPACTED. HEAVY SNOWFALL IS POSSIBLE WITH THIS SYSTEM AS STRONG FRONTOGENESIS...DEFORMATION BANDING...AND POTENTIAL TROW SET UP ACROSS THE REGION. SURFACE TEMPERATURES WILL PLAY A LARGE ROLE IN DETERMINING HOW MUCH SNOWFALL ACTUALLY ACCUMULATES. INDICATIONS ARE THAT DURING THE DAYLIGHT HOURS TEMPERATURES ACROSS THE NORTH DAKOTA WILL REMAIN WELL ABOVE FREEZING. DYNAMIC COOLING IN SNOWBANDS WOULD LIKELY REDUCE AFTERNOON HEATING...BUT REGARDLESS IT APPEARS THE MAJORITY OF ACCUMULATING SNOW WILL HAVE TO TAKE PLACE OVERNIGHT. NO HEADLINES WERE ISSUED WITH THIS FORECAST. IF TRENDS AND CONFIDENCE CONTINUE TO INCREASE...HEADLINES ARE POSSIBLE THIS WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 100 AM CDT FRI MAR 20 2015 COLD FRONT WILL MOVE SOUTH INTO THE REGION OVERNIGHT INTO FRIDAY AND WILL BE THE FOCUS FOR CLOUDS AND RAIN/SNOW ACROSS THE NORTH. THIS WILL IMPACT KISN-KMOT WITH POSSIBLE IFR CONDITIONS. REMAINDER OF THE REGION SHOULD REMAIN VFR. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...NH SHORT TERM...AYD LONG TERM...AJ AVIATION...NH
AREA FORECAST DISCUSSION
NWS MEDFORD OR
244 PM PDT FRI MAR 20 2015 .DISCUSSION...AN ACTIVE PATTERN IS IN THE WORKS STARTING THIS EVENING AND LASTING INTO THE EARLY PART OF NEXT WEEK. THE FIRST FRONT IS MAKING HEADWAY TOWARDS THE OREGON COAST. SO FAR NO RAINFALL HAS BEEN REPORTED AT ANY OF THE COASTAL LOCATIONS, BUT THE COMPOSITE RADAR IMAGES FROM MEDFORD AND EUREKA SHOW THE LEADING EDGE OF RAINFALL MOVING INTO THE OUTER MARINE WATERS. THE LATEST HRRR MODEL SHOWS RAINFALL ARRIVING AT THE COAST AROUND 5 PM PDT THEN PUSHING INLAND IN COOS AND CURRY COUNTY DURING THE EVENING. THE MODELS SHOW WEAK ELEVATED INSTABILITY OVER THE MARINE WATERS THIS EVENING, BUT HAVE NOT SEEN ANY LIGHTNING STRIKES OVER THE WATERS AND THE COLD AIR ALOFT IS STILL TO THE WEST, SO HAVE DECIDED TO REMOVE IT FROM THE FORECAST THIS EVENING. THE COLD FRONT WILL CONTINUE TO MOVE SOUTHEAST TONIGHT WITH RAIN AND HIGHER ELEVATION MOUNTAIN SNOW MAINLY ALONG AND WEST OF THE CASCADES. SNOW LEVELS START OUT AROUND 7000 FEET THIS EVENING, LOWERING TO AROUND 5500 FEET BY SATURDAY MORNING, SO WOULD NOT BE SURPRISED TO SEE ROADS SNOW COVERED NEAR DIAMOND LAKE AND CRATER LAKE AREAS BY DAYBREAK SATURDAY. THE UPPER TROUGH WILL SWING THROUGH SATURDAY MORNING THEN THE MODELS SHOW WEAK RIDGING BUILDING IN SATURDAY AFTERNOON. THIS SHOULD RESULT IN DECREASING PRECIPIATION LATE SATURDAY MORNING WITH DRY CONDITIONS MOST HOURS AND LOCATIONS SATURDAY AFTERNOON. ALSO THERE WILL BE SLIGHT WARMING ALOFT WHICH WILL REDUCE THE AMOUNT OF INSTABILITY. THE NAM SHOWS PRECIPIATION BREAKING OUT OVER NORTHERN CAL AND SOUTHWEST OREGON SATURDAY NIGHT. THE GFS ALSO SHOWS THIS,BUT TO A MUCH LESSER EXTENT AND THE EC KEEPS IT DRY. FOR NOW DID NOT MAKE ANY SIGNIFICANT CHANGES TO THE FORECAST, BUT DID EXPEND POPS FURTHER NORTH AND NORTHEAST. ANOTHER, BUT STRONGER FRONT WILL ARRIVE SUNDAY BRINGING ANOTHER ROUND OF PRECIPIATION TO THE COAST LATE SUNDAY MORNING, MOVING INLAND SUNDAY AFTERNOON. A MUCH COLDER AIRMASS ALOFT (THE COLDEST WE HAVE SEEN IN A WHILE) WILL MOVE IN SUNDAY NIGHT AND REMAIN OVERHEAD THROUGH MONDAY. SNOW LEVELS WILL FALL FROM AROUND 6000 FEET TO 4000 FEET SUNDAY NIGHT WITH PLENTY OF SHOWERS. SO IF YOU PLAN ON TRAVELING ON HIGHWAY 140 NEAR LAKE OF THE WOODS, HIGHWAY 62 NEAR CRATER LAKE, HIGHWAY 130 NEAR DIAMOND LAKE AND SISKIYOU SUMMIT SUNDAY NIGHT, BE PREPARED FOR WINTRY TRAVEL. MODELS CONTINUE TO SHOW 500 MB TEMPERATURES NEAR OR A LITTLE LOWER THEN -30 C MOVING OVER THE AREA DURING THE DAY MONDAY. IN ADDITION NEGATIVE LIFTED INDICES ARE EXPECTED. ALL THIS IN COMBINATION WITH SURFACE HEATING WILL CREATE ENOUGH INSTABILITY FOR AT LEAST ISOLATED THUNDERSTORMS MONDAY AFTERNOON. RIGHT NOW, THE BEST CHANCE FOR THUNDERSTORMS WILL BE ALONG AND EAST OF THE CASCADES FROM AROUND CRATER LAKE NORTH, THE NORTHERN HALF OF KLAMATH COUNTY AND MOST OF LAKE COUNTY, BUT THE DETAILS ON THIS ARE LIKELY TO CHANGE AS WE GET CLOSER TO MONDAY. IF NOTHING ELSE, WE`LL SEE SHOWERS INCREASE IN COVERAGE WITH SOME MODERATE TO HEAVY PRODUCING SMALL HAIL, ESPECIALLY IN THE AFTERNOON. SNOW LEVELS WILL START AROUND 4000 FEET MONDAY MORNING, THEN WE`LL HAVE A DIURNAL INCREASE TO AROUND 4500 FEET IN THE AFTERNOON. HOWEVER, THEY COULD TEMPORARILY LOWER TO 4000 FEET OR LESS IN HEAVIER SHOWERS. IF THIS HAPPENS, THEN LAKE OF THE WOODS AND SISKIYOU SUMMIT COULD SEE RAIN SHOWERS TURN TO WET SNOW SHOWERS THAT COULD BRIEFLY ACCUMULATE ON THE ROADS. A COOL MOIST NORTHWEST FLOW CONTINUES MONDAY NIGHT WITH THE BULK OF THE PRECIPIATION ALONG AND WEST OF THE CASCADES. THE GFS AND EC SHOW A WEAK LOW DEVELOPING AND MOVING TOWARDS NORTHWEST OREGON. THIS WILL BRING ANOTHER ROUND OF MODERATE PRECIPIATION AND THERE`S A CHANCE SNOW LEVELS COULD COME UP AS A WARM FRONT MOVES THROUGH. -PETRUCELLI MEDIUM RANGE FORECAST...TUESDAY THROUGH FRIDAY. THE EXTENDED PERIOD WILL START OFF WITH NEARLY ZONAL FLOW ALOFT OVER THE PACIFIC NORTHWEST. A LONG WAVE RIDGE WILL BEGIN TO BUILD OFFSHORE BETWEEN 130W AND 140W TUESDAY...AND IT WILL AMPLIFY AS IT MOVES SLOWLY EAST. FLOW ALOFT WILL BECOME NORTHWESTERLY OVER THE PACIFIC NORTHWEST. AFTER THE LAST OF THE SHORT WAVES EMBEDDED IN THE ZONAL FLOW MOVES THROUGH TUESDAY NIGHT INTO WEDNESDAY...EXPECT DRY WEATHER TO DEVELOP ALONG WITH A WARMING TREND WEDNESDAY INTO THURSDAY. BOTH THE EC AND THE GFS BREAK THE LONG WAVE RIDGE AXIS TO THE EAST OF THE MEDFORD CWA SOMETIME THURSDAY. AFTER THIS THE MODEL SOLUTIONS DIVERGE. THE EC IS THE MOST PROGRESSIVE...BRINGING THE NEXT SHORT WAVE ONSHORE FRIDAY MORNING. THE GFS DELAYS THIS WAVE UNTIL FRIDAY EVENING. THE ENSEMBLES SHOW QUITE A BIT OF SPREAD IN THE MEMBERS FROM FRIDAY ON...ESPECIALLY THE EC. SO...CONFIDENCE ON THE TIMING OF THE INCOMING SYSTEM IS LOW TO MODERATE. AT THIS TIME...WILL GO THE MIDDLE ROAD AND BRING PRECIPITATION BACK INTO THE FORECAST FRIDAY. -JRS && .AVIATION...FOR THE 20/18Z TAF CYCLE...FROM THE CASCADES EAST...VFR CONDITIONS WILL PREVAIL INITIALLY. AREAS OF MVFR CIGS/VSBYS WITH LOCAL IFR CIGS/VSBYS WILL DEVELOP OVER THE COASTAL WATERS THIS AFTERNOON...SPREAD TO THE COAST AROUND 02Z...THEN SPREAD INLAND TO THE CASCADES THROUGH 06Z WITH HIGHER TERRAIN BECOMING OBSCURED. THESE AREAS WILL CLEAR TO VFR BY SATURDAY AFTERNOON. EAST OF THE CASCADES...VFR CONDITIONS WILL PREVAIL THROUGH SATURDAY...BUT AREAS OF HIGHER TERRAIN WILL BECOME OBSCURED AFTER 06Z TONIGHT. -JRS && .MARINE...UPDATED 230 PM PDT FRIDAY 20 MAR 2015...A COLD FRONT WITH MODERATE WINDS AND HAZARDOUS SEAS WILL MOVE THROUGH THE WATERS THIS EVENING WITH A SLIGHT CHANCE OF THUNDERSTORMS. WINDS AND SEAS WILL GRADUALLY DIMINISH OVERNIGHT INTO SATURDAY NIGHT AS WEAK HIGH PRESSURE BUILDS IN. ANOTHER COLD FRONT WILL MOVE ONSHORE SUNDAY MORNING AND THIS WILL BRING ANOTHER ROUND OF SOUTH WINDS AND CHOPPY SEAS SATURDAY NIGHT INTO SUNDAY. WINDS MAY APPROACH GALE FORCE SUNDAY MORNING. A SERIES OF WEAKER DISTURBANCES WILL MOVE THROUGH THE WATERS MONDAY AND TUESDAY. SPILDE && .MFR WATCHES/WARNINGS/ADVISORIES... OR...NONE. CA...NONE. PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 9 PM PDT THIS EVENING FOR PZZ350-356-370-376. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS EVENING FOR PZZ350-356-370-376. $$
AREA FORECAST DISCUSSION
NWS MEDFORD OR
857 AM PDT FRI MAR 20 2015 .DISCUSSION...MADE MINOR ADJUSTMENTS TO THE FORECAST FOR TODAY MOSTLY TO REFLECT THE CURRENT SHORT RANGE HRRR MODEL. ALSO A HIGH AND MID LEVEL CLOUD DECK IS THINK ENOUGH TI BLOCK OUT THE SUN WEST OF THE CASCADES AND THUS SHOULD BE SUFFICIENT ENOUGH TO SLOW DOWN THE AMOUNT OF WARMING. THUS, HAVE LOWERED MAX TEMPERATURES A COUPLE OF DEGREES ON AVERAGE. ALSO TRIMMED DOWN POPS OVER THE SOUTHWEST PART OF THE AREA AND NORTHERN CASCADES. WHILE I COULD NOT RULE OUT A FEW LIGHT SHOWERS, WERE PROBABLY NOT GOING TO GET ANYTHING MEASURABLE. REGARDING THUNDERSTORMS FOR LATE THIS AFTERNOON AND TONIGHT. THE NAM SHOW WEAK ELEVATED INSTABILITY AT (850 MB) OVER THE MARINE WATERS LATE THIS AFTERNOON. ALSO LIFTED INDICES ARE BARELY IN THE NEGATIVE TERRITORY FOR TONIGHT FOR INLAND LOCATIONS. THE GFS IS MORE STABLE. BOTTOM LINE IS WE`LL TAKE A CLOSER LOOK AT THUNDERSTORM POTENTIAL FOR TONIGHT, BUT BASED ON PRELIMINARY DATA, IT DOES NOT LOOK FAVORABLE. -PETRUCELLI && .AVIATION...FOR THE 20/12Z TAF CYCLE...VFR CONDITIONS WILL CONTINUE INTO FRIDAY AFTERNOON. THE EXCEPTION IS AT THE COOS COAST (INCLUDING KOTH) WHERE MARINE STRATUS WILL BE PRESENT THROUGH THE MORNING. LOW LEVEL SOUTHERLY WINDS WILL INCREASE AND BECOME MODERATE TO STRONG THIS AFTERNOON AHEAD OF A COLD FRONT. THIS FRONT WILL SPREAD RAIN THE COAST AFTER 21Z WITH AREAS OF MVFR CONDITIONS DEVELOPING. -SVEN && .MARINE....UPDATED 530 AM PDT FRIDAY 20 MAR 2015...A COLD FRONT BRINGS MODERATE WINDS AND HAZARDOUS SEAS INTO TONIGHT. IT WILL ALSO RESULT IN A SLIGHT CHANCE OF THUNDERSTORMS TONIGHT. WINDS AND SEAS WILL GRADUALLY DIMINISH LATE TONIGHT INTO SATURDAY NIGHT AS WEAK HIGH PRESSURE BUILDS IN. ANOTHER COLD FRONT WILL BRING INCREASING SOUTH WINDS AND CHOPPY SEAS SUNDAY. THE MODELS HAVE TRENDED SLIGHTLY WEAKER WITH THIS FRONT BUT A PERIOD OF GALES IS POSSIBLE IN THE AFTERNOON AND EARLY EVENING. A SERIES OF WEAKER DISTURBANCES WILL THEN MOVE THROUGH THE WATERS SUNDAY NIGHT THROUGH TUESDAY. -SVEN && .PREV DISCUSSION... /ISSUED 600 AM PDT FRI MAR 20 2015/ DISCUSSION...AN ACTIVE PATTERN WILL BEGIN TO KICK IN TODAY, WITH THE FIRST OF TWO WET SYSTEMS PUSHING INTO THE REGION. THERE IS GOOD AGREEMENT BETWEEN THE MODELS CONCERNING THE GENERAL PROGRESSION OF THE FORECAST, BUT THERE ARE SOME DIFFERENCES IN THE DETAILS. DESPITE THESE SMALL DIFFERENCES, CONFIDENCE IS VERY GOOD. HAVE RELIED ON GENERAL MODEL BLEND FOR THE FORECAST, AND WILL DISCUSS THE POSSIBLY IMPACTFUL MODEL DIFFERENCES AS THEY COME. THE FIRST FRONTAL SYSTEM WILL MOVE ONSHORE TODAY, BRINGING A SHOT OF PRECIPITATION TO MOST OF THE AREA DURING THE EVENING AND OVERNIGHT HOURS, ESPECIALLY ALONG AND WEST OF THE CASCADES. THE FRONT APPEARS AS IF IT WILL WEAKEN AND SLOW DOWN A BIT AS IT CROSSES THE FORECAST AREA, ENDING THE BULK OF THE PRECIPITATION BY LATE MORNING. ONLY LIGHT TO MODERATE RAINFALL AMOUNTS ARE EXPECTED, ALTHOUGH SOME LOCATIONS ALONG THE COAST COULD SEE BRIEF PERIODS OF HEAVIER RAIN. ANOTHER ASPECT WORTH MENTIONING IS THAT THE COLDER AIR MOVING IN ALOFT COULD RESULT IN SOME WEAK INSTABILITY ALONG THE LEADING EDGE OF THE FRONT. THIS LINES UP WITH THE TRENDS OF THE PREVIOUS SHIFT, THEREFORE, HAVE KEPT A SLIGHT CHANCE OF THUNDER IN THE FORECAST FOR THE COAST AND WEST SIDE OVERNIGHT, THEN MOVING TO THE CASCADES AND EAST SIDE DURING THE DAY SATURDAY. ALTHOUGH MODELS DO NOT SHOW SIGNIFICANT PRECIPITATION CHANCES SATURDAY, WITH THE FRONT LINGERING IN THE AREA AND POSSIBLE INSTABILITY, FELT IT NECESSARY TO KEEP SLIGHT CHANCE OF SHOWERS, AND MAYBE SOME THUNDER, IN THE FORECAST THROUGH THE AFTERNOON. SNOW LEVELS WILL STAY ABOVE 7000 FEET FOR THE DURATION OF THIS SYSTEM. THE NEXT FRONT APPEARS STRONGER AND WETTER, AND WILL PUSH ONSHORE SUNDAY AFTERNOON. THIS SYSTEM HAS A SIGNIFICANTLY DEEPER TROUGH AND COOLER AIR THAN THE PREVIOUS SYSTEM, AND WE WILL SEE SNOW LEVELS DROP FROM AROUND 6000 FEET SUNDAY TO BELOW 4000 FEET BY MONDAY AFTERNOON. THIS TROUGH AND ITS MOISTURE ARE EXPECTED TO LINGER IN THE AREA THROUGH MUCH OF TUESDAY, AND WITH MODERATE RAINFALL RATES LIKELY, A GOOD SOAKING RAIN APPEARS TO BE IN THE WORKS. FOR AREAS ABOVE THE SNOW LEVELS, SNOWFALL COULD BE LOCALLY HEAVY AT TIMES, BUT AS OF NOW, SNOWFALL AMOUNTS WILL NOT BE OVERLY SIGNIFICANT. HOWEVER, THERE IS SNOW FORECAST FOR MANY OF THE HIGHER PASSES, AND THOSE TRAVELING DURING THIS TIME WILL NEED TO KEEP UP TO DATE WITH THE LATEST FORECASTS. WINDS WILL ALSO BE A CONCERN WITH THIS SYSTEM, WITH THE USUAL TROUBLE SPOTS, SUCH AS THE SHASTA VALLEY, SUMMER LAKE, AND THE EAST SIDE, LIKELY TO SEE GUSTY WINDS WITH THE ONSET OF THE FRONT. THE GFS SOLUTIONS IS ALSO SUGGESTING THE POSSIBILITY OF A SECONDARY SURFACE LOW FORMING UP OFFSHORE TUESDAY, AND THIS WOULD PRODUCE A LOW LEVEL JET THAT COULD BRING STRONG WINDS TO SOME AREAS. THE GFS IS THE ONLY MODEL THAT DOES THIS, SO HAVE KEPT THE WINDS DOWN FOR NOW, BUT THIS MAY NEED TO BE UPDATED WITH A LATER FORECAST PACKAGE. FOR THE LONG TERM, HIGH PRESSURE AND RIDGING SHOULD RETURN BEGINNING WEDNESDAY. WITH THE COLD AIR IN PLACE FROM THE PREVIOUS SYSTEM, AND CLEARING SKIES, TEMPERATURES COULD DROP TO BELOW NORMAL VALUES OVERNIGHT, AND THIS COULD LEAD TO SOME FROST CONCERNS. OTHERWISE, THE FORECAST APPEARS CALM, WITH ONLY A SLIGHT CHANCE OF PRECIPITATION WITH ANOTHER WEAK FRONT ON FRIDAY. THE ECMWF IS THE ONLY SOLUTION WITH THIS FEATURE, AND EVEN IT HAS BACKED OFF ON THE STRENGTH OF THE TROUGH FROM PREVIOUS RUNS. HAVE KEPT A SLIGHT CHANCE IN THE FORECAST, BUT SUSPECT THAT CONDITIONS WILL REMAIN DRY, ESPECIALLY GIVEN THE TRENDS THE PAST SEVERAL MONTHS. ASIDE FORM THE NEAR TO SLIGHTLY COOLER THAN NORMAL TEMPERATURES EXPECTED BEHIND THE FRONT EARLY IN THE WEEK, THE AREA SHOULD CONTINUE TO SEE WARMER TEMPERATURES, WITH ABOVE NORMAL DAYTIME HIGHS AND NEAR AVERAGE OVERNIGHT LOWS. && .MFR WATCHES/WARNINGS/ADVISORIES... OR...NONE. CA...NONE. PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR PZZ350-356-370-376. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM PDT SATURDAY FOR PZZ350-356-370-376. $$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
332 PM EDT FRI MAR 20 2015 .SYNOPSIS... LOW PRESSURE WILL TRACK OFF THE MID ATLANTIC COAST THIS EVENING BRINGING AN END TO OUR LATE SEASON SNOWFALL. A WEAK RIDGE OF HIGH PRESSURE WILL DRIFT EAST ACROSS THE COMMONWEALTH SATURDAY BRINGING DRY AND MILDER CONDITIONS. A STRONG COLD FRONTAL PASSAGE SATURDAY NIGHT WILL REINFORCE THE COLD AIR AND RESULT IN BELOW NORMAL TEMPERATURES SUNDAY...THROUGH EARLY NEXT WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 13Z HRRR SHOWS PRECIP EXITING MY FAR EASTERN COUNTIES BETWEEN 20-22Z. LOW CLOUDS AND PATCHY DRIZZLE/FREEZING DRIZZLE WILL PROBABLY LINGER INTO THE OVERNIGHT AS WEAK HIGH PRESSURE NOSES IN AND BRINGS LIGHT WINDS AND A LOW LEVEL SUBSIDENCE INVERSION TO KEEP MOISTURE TRAPPED. AS THE SNOW DECREASES IN INTENSITY AND THE SKIES BRIGHTEN WITH THE PASSAGE OF THE DEEPEST CLOUDS...THE HIGH LATE MARCH SUN ANGLE WILL HELP IMPROVE ROAD CONDITIONS AS WE APPROACH THE EVENING COMMUTE. THE IMPROVING CONDITIONS WILL REACH FAR EASTERN AREAS LAST. && .SHORT TERM /8 PM THIS EVENING THROUGH 6 PM SATURDAY/... DEEP...MID AND HIGH CLOUD WILL PEEL AWAY TONIGHT...WHILE EXTENSIVE/WARMER LOW CLOUDS WILL PREVAIL. TEMPS WILL DIP BACK INTO U20S AND L30S FOR LOWS TONIGHT...WITH PATCHY FREEZING DRIZZLE POSSIBLE. HAVE CONFINED THE MENTION OF FREEZING DRIZZLE TO THE HIGHER ELEVATIONS TO AVOID BEING OVERLY PESSIMISTIC OVER TOO LARGE AN AREA. THE NEXT COLD AIRMASS WILL ARRIVE WITH A COLD FRONT THAT THE NEAR TERM GUIDANCE SHOWS ENTERING MY NWRN ZONES BY AROUND MID DAY. IT WILL BE MILD AHEAD OF THE FRONT WITH LOW CHANCE POPS MAINLY FAVORING THE WESTERN AND NORTHERN HIGHER ELEVATIONS. HIGHS IN THE MID 40S TO LOWER 50S...WHILE MILD COMPARED TO RECENT CONDITIONS...WILL ACTUALLY BE ONLY NEAR OR EVEN SLIGHTLY COOLER THAN NORMAL FOR THE FIRST FULL DAY OF SPRING. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... ARCTIC HIGH WILL BUILD IN BEHIND EXITING COLD FRONT SAT NIGHT INTO MIDWEEK...WITH BELOW NORMAL TEMPS TO START THE WEEK THAT WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID 50S. SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE. BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW SHOWERS FOR LATER FRI INTO THE WEEKEND. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... WIDESPREAD IFR WILL CONTINUE THROUGH LATE DAY. SNOW WILL TAPER FROM NORTHWEST TO SOUTHEAST THROUGH MID AFTN...REACHING SERN TERMINALS BETWEEN 20-23Z. WHILE VISIBILITIES WILL TEND TO IMPROVE WITH THE ENDING OF THE STEADY SNOW...FORECAST SOUNDINGS FAVOR LOW CLOUDS LINGERING INTO THE EVENING WITH WEAK SFC FLOW AND RESIDUAL LOW LEVEL MOISTURE REMAINING IN PLACE. INCREASING WINDS AHEAD OF APPROACHING COLD FRONT SHOULD SPELL SIGNIFICANT IMPROVEMENT EAST OF THE MTNS INTO EARLY SATURDAY. OUTLOOK... SAT...MVFR CIGS NORTH AND WEST WITH ISOLD RAIN OR SNOW SHOWERS. VFR CIGS IN THE 3000-5000` RANGE CENTRAL AND EAST. SUN-TUE...VFR/NO SIG WX. WED...MAINLY VFR WITH SCATTERED RAIN SHOWERS. && .CLIMATE... SPRING OFFICIALLY BEGINS AT 645 PM EDT/2245 UTC THIS EVENING. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 PM EDT THIS EVENING FOR PAZ006- 010>012-017>019-024>028-033-036-037-041-042-045-046-049>053- 056>059-063>066. WINTER STORM WARNING UNTIL 6 PM EDT THIS EVENING FOR PAZ034- 035. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...RXR AVIATION...LA CORTE CLIMATE...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
204 PM EDT FRI MAR 20 2015 .SYNOPSIS... LOW PRESSURE WILL TRACK OFF THE MID ATLANTIC COAST THIS EVENING BRINGING AN END TO OUR LATE SEASON SNOWFALL. A WEAK RIDGE OF HIGH PRESSURE WILL DRIFT EAST ACROSS THE COMMONWEALTH SATURDAY BRINGING DRY AND MILDER CONDITIONS. A STRONG COLD FRONTAL PASSAGE SATURDAY NIGHT WILL REINFORCE THE COLD AIR AND RESULT IN BELOW NORMAL TEMPERATURES SUNDAY...THROUGH EARLY NEXT WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 13Z HRRR SHOWS PRECIP EXITING MY FAR EASTERN COUNTIES BETWEEN 20-22Z. LOW CLOUDS AND PATCHY DRIZZLE/FREEZING DRIZZLE WILL PROBABLY LINGER INTO THE OVERNIGHT AS WEAK HIGH PRESSURE NOSES IN AND BRINGS LIGHT WINDS AND A LOW LEVEL SUBSIDENCE INVERSION TO KEEP MOISTURE TRAPPED. AS THE SNOW DECREASES IN INTENSITY AND THE SKIES BRIGHTEN WITH THE PASSAGE OF THE DEEPEST CLOUDS...THE HIGH LATE MARCH SUN ANGLE WILL HELP IMPROVE ROAD CONDITIONS AS WE APPROACH THE EVENING COMMUTE. THE IMPROVING CONDITIONS WILL REACH FAR EASTERN AREAS LAST. && .SHORT TERM /8 PM THIS EVENING THROUGH 6 PM SATURDAY/... DEEP...MID AND HIGH CLOUD WILL PEEL AWAY TONIGHT...WHILE EXTENSIVE/WARMER LOW CLOUDS WILL PREVAIL. TEMPS WILL DIP BACK INTO U20S AND L30S FOR LOWS TONIGHT...WITH PATCHY FREEZING DRIZZLE POSSIBLE. HAVE CONFINED THE MENTION OF FREEZING DRIZZLE TO THE HIGHER ELEVATIONS TO AVOID BEING OVERLY PESSIMISTIC OVER TOO LARGE AN AREA. THE NEXT COLD AIRMASS WILL ARRIVE WITH A COLD FRONT THAT THE NEAR TERM GUIDANCE SHOWS ENTERING MY NWRN ZONES BY AROUND MID DAY. IT WILL BE MILD AHEAD OF THE FRONT WITH LOW CHANCE POPS MAINLY FAVORING THE WESTERN AND NORTHERN HIGHER ELEVATIONS. HIGHS IN THE MID 40S TO LOWER 50S...WHILE MILD COMPARED TO RECENT CONDITIONS...WILL ACTUALLY BE ONLY NEAR OR EVEN SLIGHTLY COOLER THAN NORMAL FOR THE FIRST FULL DAY OF SPRING. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... COLD AND DRY WX IS ON TAP FOR SUNDAY INTO EARLY NEXT WEEK...AS ARCTIC HIGH BUILDS SOUTH INTO THE REGION. 12Z GEFS PLUMES AND ECENS DATA IMPLY MONDAY WILL BE THE COLDEST DAY WITH HIGHS STRUGGLING TO HIT 32F OVR THE N MTNS AND AM LOWS IN THE LOW TEENS TO UPPER SINGLE DIGITS ACROSS THE ALLEGHENY PLATEAU. MODERATING TEMPS AND THE CHC OF RAIN SHOWERS APPEAR LKLY ARND THE MIDDLE OF NEXT WEEK...AS SFC LOW TRACKS WEST OF PA AND TRAILING COLD FRONT ARRIVES. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... WIDESPREAD IFR WILL CONTINUE THROUGH LATE DAY. SNOW WILL TAPER FROM NORTHWEST TO SOUTHEAST THROUGH MID AFTN...REACHING SERN TERMINALS BETWEEN 20-23Z. WHILE VISIBILITIES WILL TEND TO IMPROVE WITH THE ENDING OF THE STEADY SNOW...FORECAST SOUNDINGS FAVOR LOW CLOUDS LINGERING INTO THE EVENING WITH WEAK SFC FLOW AND RESIDUAL LOW LEVEL MOISTURE REMAINING IN PLACE. INCREASING WINDS AHEAD OF APPROACHING COLD FRONT SHOULD SPELL SIGNIFICANT IMPROVEMENT EAST OF THE MTNS INTO EARLY SATURDAY. OUTLOOK... SAT...MVFR CIGS NORTH AND WEST WITH ISOLD RAIN OR SNOW SHOWERS. VFR CIGS IN THE 3000-5000` RANGE CENTRAL AND EAST. SUN-TUE...VFR/NO SIG WX. WED...MAINLY VFR WITH SCATTERED RAIN SHOWERS. && .CLIMATE... SPRING OFFICIALLY BEGINS AT 645 PM EDT/2245 UTC THIS EVENING. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 PM EDT THIS EVENING FOR PAZ006- 010>012-017>019-024>028-033-036-037-041-042-045-046-049>053- 056>059-063>066. WINTER STORM WARNING UNTIL 6 PM EDT THIS EVENING FOR PAZ034- 035. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE/DEFLITCH LONG TERM...FITZGERALD/CERU AVIATION...LA CORTE CLIMATE...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1234 PM EDT FRI MAR 20 2015 .SYNOPSIS... LOW PRESSURE WILL TRACK OFF THE MID ATLANTIC COAST THIS EVENING BRINGING AN END TO OUR LATE SEASON SNOWFALL. A WEAK RIDGE OF HIGH PRESSURE WILL DRIFT EAST ACROSS THE COMMONWEALTH SATURDAY BRINGING DRY AND MILDER CONDITIONS. A STRONG COLD FRONTAL PASSAGE SATURDAY NIGHT WILL REINFORCE THE COLD AIR AND RESULT IN BELOW NORMAL TEMPERATURES SUNDAY...THROUGH EARLY NEXT WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 13Z HRRR SHOWS PRECIP EXITING MY FAR EASTERN COUNTIES BETWEEN 20-22Z. LOW CLOUDS AND PATCHY DRIZZLE/FREEZING DRIZZLE WILL PROBABLY LINGER INTO THE OVERNIGHT AS WEAK HIGH PRESSURE NOSES IN AND BRINGS LIGHT WINDS AND A LOW LEVEL SUBSIDENCE INVERSION TO KEEP MOISTURE TRAPPED. AS THE SNOW DECREASES IN INTENSITY AND THE SKIES BRIGHTEN WITH THE PASSAGE OF THE DEEPEST CLOUDS...THE HIGH LATE MARCH SUN ANGLE WILL HELP IMPROVE ROAD CONDITIONS AS WE APPROACH THE EVENING COMMUTE. THE IMPROVING CONDITIONS WILL REACH FAR EASTERN AREAS LAST. && .SHORT TERM /8 PM THIS EVENING THROUGH 6 PM SATURDAY/... DEEP...MID AND HIGH CLOUD WILL PEEL AWAY TONIGHT...WHILE EXTENSIVE/WARMER LOW CLOUDS WILL PREVAIL. TEMPS WILL DIP BACK INTO U20S AND L30S FOR LOWS TONIGHT...WITH PATCHY FREEZING DRIZZLE POSSIBLE. A FAIR AMT OF AGREEMENT THRU THE WEEKEND AMONG MED RANGE GUIDANCE...ALL OF WHICH SHOW A PIECE OF THE POLAR VORTEX HEADING SE FROM HUDSON BAY INTO SOUTHERN QUEBEC...PUSHING A SHARP COLD FRONT THRU PA SATURDAY AFTERNOON/EVENING. TEMPS SHOULD REACH NEAR OR ABOVE SEASONAL NORMS AHEAD OF FRONT SATURDAY. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... COLD AND DRY WX IS ON TAP FOR SUNDAY INTO EARLY NEXT WEEK...AS ARCTIC HIGH BUILDS SOUTH INTO THE REGION. 12Z GEFS PLUMES AND ECENS DATA IMPLY MONDAY WILL BE THE COLDEST DAY WITH HIGHS STRUGGLING TO HIT 32F OVR THE N MTNS AND AM LOWS IN THE LOW TEENS TO UPPER SINGLE DIGITS ACROSS THE ALLEGHENY PLATEAU. MODERATING TEMPS AND THE CHC OF RAIN SHOWERS APPEAR LKLY ARND THE MIDDLE OF NEXT WEEK...AS SFC LOW TRACKS WEST OF PA AND TRAILING COLD FRONT ARRIVES. && .AVIATION /16Z FRIDAY THROUGH WEDNESDAY/... WIDESPREAD IFR WILL CONTINUE THROUGH LATE DAY. SNOW WILL TAPER FROM NORTHWEST TO SOUTHEAST THROUGH MID AFTN...REACHING SERN TERMINALS BETWEEN 20-23Z. WHILE VISIBILITIES WILL TEND TO IMPROVE WITH THE ENDING OF THE STEADY SNOW...FORECAST SOUNDINGS FAVOR LOW CLOUDS LINGERING INTO THE EVENING WITH WEAK SFC FLOW AND RESIDUAL LOW LEVEL MOISTURE REMAINING IN PLACE. INCREASING WINDS AHEAD OF APPROACHING COLD FRONT SHOULD SPELL SIGNIFICANT IMPROVEMENT EAST OF THE MTNS INTO EARLY SATURDAY. OUTLOOK... SAT...MVFR CIGS NORTH AND WEST WITH ISOLD RAIN OR SNOW SHOWERS. VFR CIGS IN THE 3000-5000` RANGE CENTRAL AND EAST. SUN-TUE...VFR/NO SIG WX. WED...MAINLY VFR WITH SCATTERED RAIN SHOWERS. && .CLIMATE... SPRING OFFICIALLY BEGINS AT 645 PM EDT/2245 UTC THIS EVENING. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 PM EDT THIS EVENING FOR PAZ006- 010>012-017>019-024>028-033-036-037-041-042-045-046-049>053- 056>059-063>066. WINTER STORM WARNING UNTIL 6 PM EDT THIS EVENING FOR PAZ034- 035. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LAMBERT LONG TERM...FITZGERALD/CERU AVIATION...LA CORTE CLIMATE...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1025 AM EDT FRI MAR 20 2015 .SYNOPSIS... LOW PRESSURE WILL TRACK ACROSS THE MID ATLANTIC STATES AND BRING A LATE SEASON SNOWFALL TO THE AREA TODAY. A WEAK RIDGE OF HIGH PRESSURE WILL DRIFT EAST ACROSS THE COMMONWEALTH SATURDAY BRINGING DRY AND MILDER CONDITIONS. A STRONG COLD FRONTAL PASSAGE SATURDAY NIGHT WILL REINFORCE THE COLD AIR AND RESULT IN BELOW NORMAL TEMPERATURES SUNDAY...THROUGH EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LATEST HRRR SHOWS PRECIP WINDING DOWN RAPIDLY THIS AFTERNOON AS FORCING WANES AND QUICKLY MOVES EAST OF THE REGION. FROM EARLIER... MODELS REMAIN CONSISTENT IN BRINGING A WEAK LOW TOWARD SWRN PA BY MIDDAY...BEFORE A STRONGER SECONDARY FORMS ON THE MID ATLANTIC COAST AND MOVES OUT OVER THE OCEAN TONIGHT AND SATURDAY. WHILE THE SURFACE LOW(S) WILL BE UNIMPRESSIVE...THE ASSOCIATED LARGE SCALE FORCING WILL BE RATHER VIGOROUS. THE POTENT COUPLED UPPER JET IS USED TO GENERATE A PERIOD OF STRONG FRONTOGENESIS AND WARM ADVECTION WHICH WILL RESULT IN AN 6-9 HOUR PERIOD OF LIGHT TO MODERATE SNOW FOR CENTRAL AND SOUTHERN PA. ROAD CONDITIONS TODAY...AS IS COMMON WITH PRACTICALLY ALL LATE MARCH SNOWSTORMS...WILL BE STRONGLY DICTATED BY THE INTENSITY OF THE SNOW. INITIALLY...WITH NEAR OR A FEW DEG F ABOVE FREEZING RIGHT AT THE ONSET...ROADS WILL BE WET. THE MID TO LATE MORNING HOURS ACROSS THE EASTERN RIDGES OF THE LAURELS AND THROUGH THE SOUTHERN AND CENTRAL MTNS WILL CONTAIN THE BEST CHANCE OF ADVERSE TRAVEL CONDITIONS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... THE SNOW WILL WIND DOWN RATHER QUICKLY IN THE MID AFTERNOON TODAY. AS THE PRECIP RATES DIMINISH BY 17-20Z EARLY AFTERNOON...IMPACTS FROM ANY LINGERING LIGHT SNOW THAT IS FALLING WILL DECREASE AS TREATED ROADS...MARGINAL SKIN TEMPS AND THE HIGH MARCH SUN ANGLES WILL ALL WORK TO MINIMIZE ADDITIONAL ACCUMULATIONS. DEEP...MID AND HIGH CLOUD WILL PEEL AWAY TONIGHT...WHILE EXTENSIVE/WARMER LOW CLOUDS WILL PREVAIL. TEMPS WILL DIP BACK INTO U20S AND L30S FOR LOWS TONIGHT...WITH PATCHY FREEZING DRIZZLE POSSIBLE. A FAIR AMT OF AGREEMENT THRU NEXT WEEKEND AMONG MED RANGE GUIDANCE...ALL OF WHICH SHOW A PIECE OF THE POLAR VORTEX HEADING SE FROM HUDSON BAY INTO SOUTHERN QUEBEC...PUSHING A SHARP COLD FRONT THRU PA SATURDAY AFTERNOON/EVENING. TEMPS SHOULD REACH NEAR OR ABOVE SEASONAL NORMS AHEAD OF FRONT SATURDAY. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... COLD AND DRY WX IS ON TAP FOR SUNDAY INTO EARLY NEXT WEEK...AS ARCTIC HIGH BUILDS SOUTH INTO THE REGION. 12Z GEFS PLUMES AND ECENS DATA IMPLY MONDAY WILL BE THE COLDEST DAY WITH HIGHS STRUGGLING TO HIT 32F OVR THE N MTNS AND AM LOWS IN THE LOW TEENS TO UPPER SINGLE DIGITS ACROSS THE ALLEGHENY PLATEAU. MODERATING TEMPS AND THE CHC OF RAIN SHOWERS APPEAR LKLY ARND THE MIDDLE OF NEXT WEEK...AS SFC LOW TRACKS WEST OF PA AND TRAILING COLD FRONT ARRIVES. && .AVIATION /14Z FRIDAY THROUGH TUESDAY/... WIDESPREAD IFR WILL CONTINUE INTO THE AFTERNOON. SNOW WILL TAPER FROM NORTHWEST TO SOUTHEAST THROUGH MID AFTN BUT NOT END UNTIL THE 20-23Z TIMEFRAME AT MDT AND LNS. FORECAST SOUNDINGS FAVOR LOW CLOUDS AND SOME VIZ REDUCTIONS LINGERING INTO THE EVENING WITH WEAK SFC FLOW AND RESIDUAL LOW LEVEL MOISTURE REMAINING IN PLACE. INCREASING WINDS AHEAD OF APPROACHING COLD FRONT SHOULD SPELL SIGNIFICANT IMPROVEMENT EAST OF THE MTNS INTO EARLY SATURDAY. OUTLOOK... SAT...MVFR CIGS WEST WITH ISOLD -SHSN PSBL. VFR CIGS IN THE 3000-5000` RANGE CENTRAL AND EAST. 20-30KT WIND GUSTS FROM 270-320 ASSOCD WITH COLD FROPA. SUN-TUE...VFR/NO SIG WX. && .CLIMATE... SPRING OFFICIALLY BEGINS AT 645 PM EDT TODAY. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 PM EDT THIS EVENING FOR PAZ006- 010>012-017>019-024>028-033-036-037-041-042-045-046-049>053- 056>059-063>066. WINTER STORM WARNING UNTIL 6 PM EDT THIS EVENING FOR PAZ034- 035. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...DANGELO/LA CORTE/LAMBERT SHORT TERM...LAMBERT LONG TERM...FITZGERALD/CERU AVIATION...LA CORTE/STEINBUGL CLIMATE...
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1203 PM CDT FRI MAR 20 2015 .AVIATION 18Z DISCUSSION... THE DEEPER MOISTURE WILL BE SHIFTING SOUTH OF MIDDLE TN BY 00Z. AS A RESULT...THE LIGHT SHOWER ACTIVITY WILL CONTINUE TO DECREASE IN COVERAGE. OTW...LOW CIGS TO PERSIST INTO THIS AFTERNOON WITH PARTIAL CLEARING BY LATE TONIGHT. VSBYS IN THE 3SM-5SM RANGE WILL BE POSSIBLE UNTIL 12Z...MAINLY ACROSS THE PLATEAU. && .PREV DISCUSSION... /ISSUED 1047 AM CDT FRI MAR 20 2015/ DISCUSSION... SHOWER ACTIVITY HAS DECREASED IN COVERAGE AND INTENSITY OVER THE PAST FEW HOURS. CURRENTLY...JUST PATCHY LIGHT ACTIVITY EXISTS ACROSS SOUTHERN AREAS. MODELS INDICATE THAT THE DEEPER MOISTURE WILL MOVE OFF TO THE SOUTH BY 00Z. HRRR AGREES WITH THIS AND WILL THEREFORE BEGIN TO LOWER POPS FOR TODAY. WILL INCLUDE JUST A SLIGHT CHANCE OF SHOWERS NW BEFORE 1 PM...WITH LOW POPS ELSEWHERE. OTW...CLOUDINESS WILL PERSIST SO HIGH TEMPS SHOULD HOLD IN THE UPPER 50S OR SO. UPDATE OUT SHORTLY. PREV DISCUSSION... /ISSUED 448 AM CDT FRI MAR 20 2015/ UPDATE... 12Z TAFS. AVIATION... DETERIORATED CONDITIONS EXPECTED TO CONTINUE INTO THE EVENING CKV/BNA AND WELL THROUGH TONIGHT CSV IN THE WAKE OF A PASSING COLD FRONT. CIGS/VSBYS EXPECTED TO REMAIN LARGELY MVFR/IFR THROUGH TODAY BNA/CKV BUT IMPROVEMENT IS LIKELY EARLY TONIGHT. EARLY MORNING FOG HOWEVER EXPECTED TO FORM 08-12Z. CSV LIKELY TO REMAIN LARGELY IFR THROUGH THE PERIOD. BRIEF IMPROVEMENT POSSIBLE EARLY TONIGHT BUT FOG EXPECTED TO QUICKLY REDEVELOP BRINGING VSBYS BACK DOWN TOWARD 06Z AND OVERNIGHT. PREV DISCUSSION... /ISSUED 253 AM CDT FRI MAR 20 2015/ DISCUSSION... UPPER TROUGH TO OUR WEST WILL BRING LIGHT RAIN INTO NORTHWEST MIDDLE TENNESSEE BY 5 OR 6 AM THIS MORNING WITH THE RAIN TRANSLATING EASTWARD AS WE GO THROUGH THE DAY. BY NOON AREAS NORTH AND WEST OF NASHVILLE SHOULD BE RAIN FREE WITH RAIN CONTINUING SOUTHEAST HALF OF MIDDLE TENNESSEE BUT END FROM THE WEST DURING THE AFTERNOON HOURS. LOOKING FOR CLOUDY SKIES MUCH OF THE DAY BUT SHOULD SEE DECREASING CLOUDS BEGINNING OVER THE NORTHWEST BY MID AFTERNOON WHICH WOULD INCLUDE A FEW RAYS OF SUN. NOT AS COOL TODAY AS YESTERDAY BUT NO BIG WARM UP EITHER WITH HIGHS IN THE MID 50S PLATEAU AND IN THE UPPER 50S TO AROUND 60 ELSEWHERE. 1021 MBAR SURFACE RIDGE TAKES OVER TONIGHT AND SATURDAY AS MID STATE REMAINS IN THE MIDDLE OF SPLIT UPPER FLOW PATTERN INTO SATURDAY. HIGHS ON SATURDAY WILL CLIMB INTO THE UPPER 60S AT MANY LOCATIONS. BY SATURDAY NIGHT SOUTHERN STREAM STARTS WORKING UPPER TROUGH IN THIS DIRECTION FROM SOUTH TEXAS...BELIEVE EURO HAS BEST HANDLE ON THIS FEATURE WHICH WILL BRING A LIGHT RAIN CHANCE FOR THE SOUTH HALF OF MID STATE DURING THE DAY SUNDAY. HIGHS ON SUNDAY WILL BE TRICKY DUE TO CLOUD COVER AND RAIN CHANCE BUT GENERALLY IN THE 60S. STILL A SLIGHT CHANCE OF RAIN SOUTHEAST HALF SUNDAY NIGHT AS UPPER TROUGH AND ATTENDANT SURFACE LOW REMAIN NEARBY. NO RAIN MONDAY AND TUESDAY BUT I DID INCLUDE A SLIGHT CHANCE FOR WEDNESDAY AS FRONTAL SYSTEM APPROACHES FROM THE NORTHWEST THEN BUMP UP POPS WEDNESDAY NIGHT THROUGH FRIDAY AS UPPER TROUGH ONCE AGAIN DOMINATES EASTERN U.S. WITH ENERGY WORKING ACROSS OUR AREA. HIGHS NEXT WEEK GENERALLY IN THE 60S EACH DAY WITH LOWS IN THE 40S MONDAY INTO WEDNESDAY...AROUND 50 THURSDAY MORNING THEN IN THE 40S FRIDAY MORNING AND IN THE 30S SATURDAY MORNING. CLIMATE...AVERAGE DATE OF THE LAST 32 DEGREE TEMPERATURE IN THE SPRING AT NASHVILLE IS APRIL 6TH. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1047 AM CDT FRI MAR 20 2015 .DISCUSSION... SHOWER ACTIVITY HAS DECREASED IN COVERAGE AND INTENSITY OVER THE PAST FEW HOURS. CURRENTLY...JUST PATCHY LIGHT ACTIVITY EXISTS ACROSS SOUTHERN AREAS. MODELS INDICATE THAT THE DEEPER MOISTURE WILL MOVE OFF TO THE SOUTH BY 00Z. HRRR AGREES WITH THIS AND WILL THEREFORE BEGIN TO LOWER POPS FOR TODAY. WILL INCLUDE JUST A SLIGHT CHANCE OF SHOWERS NW BEFORE 1 PM...WITH LOW POPS ELSEWHERE. OTW...CLOUDINESS WILL PERSIST SO HIGH TEMPS SHOULD HOLD IN THE UPPER 50S OR SO. UPDATE OUT SHORTLY. && .PREV DISCUSSION... /ISSUED 448 AM CDT FRI MAR 20 2015/ UPDATE... 12Z TAFS. AVIATION... DETERIORATED CONDITIONS EXPECTED TO CONTINUE INTO THE EVENING CKV/BNA AND WELL THROUGH TONIGHT CSV IN THE WAKE OF A PASSING COLD FRONT. CIGS/VSBYS EXPECTED TO REMAIN LARGELY MVFR/IFR THROUGH TODAY BNA/CKV BUT IMPROVEMENT IS LIKELY EARLY TONIGHT. EARLY MORNING FOG HOWEVER EXPECTED TO FORM 08-12Z. CSV LIKELY TO REMAIN LARGELY IFR THROUGH THE PERIOD. BRIEF IMPROVEMENT POSSIBLE EARLY TONIGHT BUT FOG EXPECTED TO QUICKLY REDEVELOP BRINGING VSBYS BACK DOWN TOWARD 06Z AND OVERNIGHT. PREV DISCUSSION... /ISSUED 253 AM CDT FRI MAR 20 2015/ DISCUSSION... UPPER TROUGH TO OUR WEST WILL BRING LIGHT RAIN INTO NORTHWEST MIDDLE TENNESSEE BY 5 OR 6 AM THIS MORNING WITH THE RAIN TRANSLATING EASTWARD AS WE GO THROUGH THE DAY. BY NOON AREAS NORTH AND WEST OF NASHVILLE SHOULD BE RAIN FREE WITH RAIN CONTINUING SOUTHEAST HALF OF MIDDLE TENNESSEE BUT END FROM THE WEST DURING THE AFTERNOON HOURS. LOOKING FOR CLOUDY SKIES MUCH OF THE DAY BUT SHOULD SEE DECREASING CLOUDS BEGINNING OVER THE NORTHWEST BY MID AFTERNOON WHICH WOULD INCLUDE A FEW RAYS OF SUN. NOT AS COOL TODAY AS YESTERDAY BUT NO BIG WARM UP EITHER WITH HIGHS IN THE MID 50S PLATEAU AND IN THE UPPER 50S TO AROUND 60 ELSEWHERE. 1021 MBAR SURFACE RIDGE TAKES OVER TONIGHT AND SATURDAY AS MID STATE REMAINS IN THE MIDDLE OF SPLIT UPPER FLOW PATTERN INTO SATURDAY. HIGHS ON SATURDAY WILL CLIMB INTO THE UPPER 60S AT MANY LOCATIONS. BY SATURDAY NIGHT SOUTHERN STREAM STARTS WORKING UPPER TROUGH IN THIS DIRECTION FROM SOUTH TEXAS...BELIEVE EURO HAS BEST HANDLE ON THIS FEATURE WHICH WILL BRING A LIGHT RAIN CHANCE FOR THE SOUTH HALF OF MID STATE DURING THE DAY SUNDAY. HIGHS ON SUNDAY WILL BE TRICKY DUE TO CLOUD COVER AND RAIN CHANCE BUT GENERALLY IN THE 60S. STILL A SLIGHT CHANCE OF RAIN SOUTHEAST HALF SUNDAY NIGHT AS UPPER TROUGH AND ATTENDANT SURFACE LOW REMAIN NEARBY. NO RAIN MONDAY AND TUESDAY BUT I DID INCLUDE A SLIGHT CHANCE FOR WEDNESDAY AS FRONTAL SYSTEM APPROACHES FROM THE NORTHWEST THEN BUMP UP POPS WEDNESDAY NIGHT THROUGH FRIDAY AS UPPER TROUGH ONCE AGAIN DOMINATES EASTERN U.S. WITH ENERGY WORKING ACROSS OUR AREA. HIGHS NEXT WEEK GENERALLY IN THE 60S EACH DAY WITH LOWS IN THE 40S MONDAY INTO WEDNESDAY...AROUND 50 THURSDAY MORNING THEN IN THE 40S FRIDAY MORNING AND IN THE 30S SATURDAY MORNING. CLIMATE...AVERAGE DATE OF THE LAST 32 DEGREE TEMPERATURE IN THE SPRING AT NASHVILLE IS APRIL 6TH. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 58 42 68 47 / 40 05 05 05 CLARKSVILLE 57 40 67 47 / 20 05 0 0 CROSSVILLE 55 39 65 43 / 50 10 10 05 COLUMBIA 60 42 67 47 / 40 10 10 10 LAWRENCEBURG 61 43 69 48 / 40 10 10 20 WAVERLY 59 42 68 48 / 20 05 05 0 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1237 PM CDT FRI MAR 20 2015 .AVIATION.../18Z TAFS/ CONCERNS THIS FORECAST PERIOD WILL BE THE SOUTHWARD PROGRESSION OF WEAK COLD FRONT AND THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS. IFR/MVFR CIGS AT ALL SITES TO BEGIN THIS FORECAST PERIOD. ONCE STEADIER RAINFALL BEGINS CIGS WILL FALL TO IFR. VSBYS WILL BE REDUCED TO 3SM-5SM. WEAK COLD FRONT REMAINS JUST NORTH OF THE REGION. STILL EXPECTED THE FRONT TO ARRIVE AT KAUS 21Z-22Z AND KSAT/KSSF 23Z-00Z. WINDS BE EASTERLY AT 5-10 KNOTS AHEAD OF THE FRONT AND NORTHEAST AT 8-12 KNOTS BEHIND THE FRONT. AFTER FROPA WILL SEE RAIN/SHOWERS AND THUNDERSTORMS FOR THE REMAINDER OF THE FORECAST. TIMING OF THE CONVECTION IS UNCERTAIN AT THIS TIME AND HAVE NOT SPECIFICALLY INCLUDED IN THE FORECAST. WILL CONTINUE TO MONITOR AND MAKE UPDATES AS NECESSARY. && .PREV DISCUSSION... /ISSUED 654 AM CDT FRI MAR 20 2015/ AVIATION... IFR/MVFR CIGS/VSBYS WILL LIFT TO MAINLY MVFR LATE MORNING THROUGH AFTERNOON INTO EARLY THIS EVENING...THEN FALL BACK TO IFR TONIGHT. LIFR CIGS ARE POSSIBLE THIS MORNING AND AGAIN TONIGHT INTO SATURDAY MORNING. SHRA/TSRA WILL BECOME MORE WIDESPREAD TODAY AS A COLD FRONT MOVES ACROSS THE AREA AND AN UPPER LEVEL TROUGH APPROACHES. S TO SE WINDS LESS THAN 10 KTS WILL SHIFT TO N TO NE AT 5 TO 12 KTS AFTER THE FRONTAL PASSAGE. PREV DISCUSSION... /ISSUED 425 AM CDT FRI MAR 20 2015/ SHORT TERM (TODAY THROUGH SATURDAY)... .PERIODS OF HEAVY RAINFALL EXPECTED TODAY INTO SATURDAY... MAIN FOCUS NEXT 48 HOURS WILL CENTER AROUND MODERATE TO HEAVY RAIN THAT WILL LIKELY CAUSE LOCALIZED TO AREAS OF FLASH FLOODING IMPACTS WITH WIDESPREAD 2-4 INCHES WITH LOCALLY HIGHER AMOUNTS UP TO 6 INCHES CONFINED TO NARROW AXES. HAVE UPDATED THE FLASH FLOOD WATCH TO INCLUDE ALL AREAS WEST TO THE RIO GRANDE AND HAVE MOVED UP THE START TIME TO 1PM THIS AFTERNOON. A SEGMENTED WATCH COULD HAVE BEEN MADE BUT DECIDED TO KEEP THE MESSAGING AS SIMPLE AS POSSIBLE. THE UPDATED FLASH FLOOD WATCH WILL BE POSTED BY 6AM THIS MORNING. THE WATCH WAS EXTENDED WESTWARD GIVEN NEW HI-RES ARW/NMM SUPPORT AND A BULLISH HRRR THROUGH THE EARLY TO MID AFTERNOON HOURS. IN ADDITION...THE RUN TO RUN CONSISTENCY OF THE ECMWF CONTINUES TO HIGHLIGHT VAL VERDE COUNTY AND SURROUNDING AREAS FOR HIGHER TOTALS WHERE LIMITED SOIL DEPTH WITH COMPOUND FLOODING ISSUES QUICKLY. AT THIS TIME...A COLD FRONT IS LOCATED ALONG A LINE FROM SAN ANGELO TOWARD FORTH WORTH AND MOVING SOUTH. SPC MESOANALYSIS IS INDICATING STRONGER MID AND UPPER LEVEL DIVERGENCE OVERSPREADING THE BIG BEND OF TEXAS AND COUPLED WITH THE LOW-LEVEL FRONTAL CONVERGENCE...IS AIDING ELEVATED THUNDERSTORM DEVELOPMENT ACROSS WEST-CENTRAL TEXAS. THE BOUNDARY WILL CONTINUE SOUTH AND AS ADDITIONAL SYNOPTIC LIFT SHIFTS NORTHEAST FROM A WEAK EJECTING SHORTWAVE TROUGH...FURTHER SHOWER AND THUNDERSTORM DEVELOPMENT IS EXPECTED THROUGH THE MORNING HOURS FOR THE EDWARDS PLATEAU INTO THE RIO GRANDE VALLEY. THIS ACTIVITY IS EXPECTED TO PROGRESS SOUTH AND EAST THROUGH MID-DAY INTO THE I-35 CORRIDOR AND SE AREAS BY LATE AFTERNOON. WITH SUBTLE MID LEVEL HEIGHT FALLS AIDING IN MID LEVEL COOLING...ELEVATED INSTABILITY WILL RANGE FROM 300 J/KG IN HILL COUNTRY TO NEAR 1000 J/KG ALONG AN AXIS EXTENDING FROM THE RIO GRANDE NE TOWARDS THE 35 CORRIDOR AND POINTS SOUTHEAST. FEEL THIS AREA WHERE BEST ELEVATED INSTABILITY COMBINED WITH STRONGEST LOW-LEVEL CONVERGENCE EXISTS WILL LIKELY SEE THE HEAVIER RAINFALL TOTALS THROUGH THIS AFTERNOON. FEEL THERE WILL BE A WEAKENING TREND BY EVENING WITH RAINFALL RATES LOWERING AS THE REGION WILL BE BETWEEN IMPULSES. ANOTHER ROUND OF HEAVIER RAIN LOOKS TO ORGANIZE OVERNIGHT FRIDAY INTO SATURDAY MORNING AS ANOTHER IMPULSE EJECTS AHEAD OF THE PARENT CUT-FF LOW AND H5 TO H3 WIND SPEEDS INCREASE. GLOBAL MODELS ALONG WITH THE NAM SUGGEST THE HEAVIEST AXIS WILL BE EITHER ALONG THE I-35 CORRIDOR OR JUST SOUTHEAST. THIS BANDING OF SHOWERS AND THUNDERSTORMS WILL LIKELY BE TAPPING INTO PWATS OF 1.5" TO 1.8" AND FEEL THIS TIME FRAME FROM 1AM SATURDAY MORNING TO EARLY AFTERNOON WILL BE OF HIGH CONCERN DEPENDING ON EXACT EVOLUTION AND GEOGRAPHICAL PLACEMENT FOR FLOODING ISSUES. FINALLY...A DEVELOPING SURFACE LOW WILL HELP DRIVE THE FRONT THROUGH THE AREA LATE SATURDAY INTO EARLY SUNDAY AND HELP SLOWLY DIMINISH RAIN/TSTORM CHANCES AS THE MID LEVEL LOW SHIFTS EAST ACROSS NE TEXAS. LONG TERM (SATURDAY NIGHT THROUGH THURSDAY)... NO IMPACTS TO HIGHLIGHT FOR THE LONG TERM AS MUCH DRIER CONDITIONS ARE EXPECTED MONDAY THROUGH AT LEAST WEDNESDAY BEFORE ANOTHER FRONT POSSIBLY MOVES THROUGH ON THURSDAY OF NEXT WEEK. AN AXIS OF HIGH PRESSURE AND BELOW 0.9" PWATS WILL KEEP ATMOSPHERE STABILIZED AND DRY THROUGH THE EARLY AND MID PORTIONS OF NEXT WEEK WITH THE JET STREAM SHIFTING NORTH. THE SOUTHERN BRANCH OF THE JET STREAM LOOKS TO RELAX SLIGHTLY WITH ONLY A WEAK TROUGH NOTED ACROSS NORTHERN MEXICO BY WEDNESDAY. HOWEVER...GLOBAL MODELS SUGGEST THAT STRONGER NORTHERN STREAM TROUGHING COULD HELP BUCKLE THE SOUTHERN BRANCH ONCE GAIN AND FORCE ANOTHER CUT-OFF LOW SITUATION BY NEXT WEEKEND. TEMPERATURES WILL BE NEAR NORMAL FOR THIS TIME OF YEAR THROUGH THE WEEK. /ALLEN/ && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 72 58 66 58 74 / 100 100 90 70 20 AUSTIN BERGSTROM INTL AIRPORT 72 59 65 58 73 / 100 100 100 70 20 NEW BRAUNFELS MUNI AIRPORT 74 60 67 58 76 / 90 100 100 60 20 BURNET MUNI AIRPORT 67 55 63 56 71 / 100 80 80 70 20 DEL RIO INTL AIRPORT 70 59 69 56 79 / 100 80 80 30 10 GEORGETOWN MUNI AIRPORT 70 57 64 57 72 / 100 100 90 70 20 HONDO MUNI AIRPORT 73 60 68 57 77 / 100 90 90 50 20 SAN MARCOS MUNI AIRPORT 73 60 66 57 75 / 90 100 100 70 20 LA GRANGE - FAYETTE REGIONAL 75 62 68 60 74 / 90 100 100 70 20 SAN ANTONIO INTL AIRPORT 75 60 67 59 76 / 90 100 90 60 20 STINSON MUNI AIRPORT 74 60 68 59 77 / 90 100 90 60 20 && .EWX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR THE FOLLOWING COUNTIES: ATASCOSA...BANDERA...BASTROP...BEXAR...BLANCO...BURNET... CALDWELL...COMAL...DE WITT...DIMMIT...EDWARDS...FAYETTE...FRIO... GILLESPIE...GONZALES...GUADALUPE...HAYS...KARNES...KENDALL...KERR... KINNEY...LAVACA...LEE...LLANO...MAVERICK...MEDINA...REAL...TRAVIS... UVALDE...VAL VERDE...WILLIAMSON...WILSON...ZAVALA. && $$ MESOSCALE/AVIATION...10 SYNOPTIC/GRIDS...00/24 PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
654 AM CDT FRI MAR 20 2015 .AVIATION... IFR/MVFR CIGS/VSBYS WILL LIFT TO MAINLY MVFR LATE MORNING THROUGH AFTERNOON INTO EARLY THIS EVENING...THEN FALL BACK TO IFR TONIGHT. LIFR CIGS ARE POSSIBLE THIS MORNING AND AGAIN TONIGHT INTO SATURDAY MORNING. SHRA/TSRA WILL BECOME MORE WIDESPREAD TODAY AS A COLD FRONT MOVES ACROSS THE AREA AND AN UPPER LEVEL TROUGH APPROACHES. S TO SE WINDS LESS THAN 10 KTS WILL SHIFT TO N TO NE AT 5 TO 12 KTS AFTER THE FRONTAL PASSAGE. && .PREV DISCUSSION... /ISSUED 425 AM CDT FRI MAR 20 2015/ SHORT TERM (TODAY THROUGH SATURDAY)... ..PERIODS OF HEAVY RAINFALL EXPECTED TODAY INTO SATURDAY... MAIN FOCUS NEXT 48 HOURS WILL CENTER AROUND MODERATE TO HEAVY RAIN THAT WILL LIKELY CAUSE LOCALIZED TO AREAS OF FLASH FLOODING IMPACTS WITH WIDESPREAD 2-4 INCHES WITH LOCALLY HIGHER AMOUNTS UP TO 6 INCHES CONFINED TO NARROW AXES. HAVE UPDATED THE FLASH FLOOD WATCH TO INCLUDE ALL AREAS WEST TO THE RIO GRANDE AND HAVE MOVED UP THE START TIME TO 1PM THIS AFTERNOON. A SEGMENTED WATCH COULD HAVE BEEN MADE BUT DECIDED TO KEEP THE MESSAGING AS SIMPLE AS POSSIBLE. THE UPDATED FLASH FLOOD WATCH WILL BE POSTED BY 6AM THIS MORNING. THE WATCH WAS EXTENDED WESTWARD GIVEN NEW HI-RES ARW/NMM SUPPORT AND A BULLISH HRRR THROUGH THE EARLY TO MID AFTERNOON HOURS. IN ADDITION...THE RUN TO RUN CONSISTENCY OF THE ECMWF CONTINUES TO HIGHLIGHT VAL VERDE COUNTY AND SURROUNDING AREAS FOR HIGHER TOTALS WHERE LIMITED SOIL DEPTH WITH COMPOUND FLOODING ISSUES QUICKLY. AT THIS TIME...A COLD FRONT IS LOCATED ALONG A LINE FROM SAN ANGELO TOWARD FORTH WORTH AND MOVING SOUTH. SPC MESOANALYSIS IS INDICATING STRONGER MID AND UPPER LEVEL DIVERGENCE OVERSPREADING THE BIG BEND OF TEXAS AND COUPLED WITH THE LOW-LEVEL FRONTAL CONVERGENCE...IS AIDING ELEVATED THUNDERSTORM DEVELOPMENT ACROSS WEST-CENTRAL TEXAS. THE BOUNDARY WILL CONTINUE SOUTH AND AS ADDITIONAL SYNOPTIC LIFT SHIFTS NORTHEAST FROM A WEAK EJECTING SHORTWAVE TROUGH...FURTHER SHOWER AND THUNDERSTORM DEVELOPMENT IS EXPECTED THROUGH THE MORNING HOURS FOR THE EDWARDS PLATEAU INTO THE RIO GRANDE VALLEY. THIS ACTIVITY IS EXPECTED TO PROGRESS SOUTH AND EAST THROUGH MID-DAY INTO THE I-35 CORRIDOR AND SE AREAS BY LATE AFTERNOON. WITH SUBTLE MID LEVEL HEIGHT FALLS AIDING IN MID LEVEL COOLING...ELEVATED INSTABILITY WILL RANGE FROM 300 J/KG IN HILL COUNTRY TO NEAR 1000 J/KG ALONG AN AXIS EXTENDING FROM THE RIO GRANDE NE TOWARDS THE 35 CORRIDOR AND POINTS SOUTHEAST. FEEL THIS AREA WHERE BEST ELEVATED INSTABILITY COMBINED WITH STRONGEST LOW-LEVEL CONVERGENCE EXISTS WILL LIKELY SEE THE HEAVIER RAINFALL TOTALS THROUGH THIS AFTERNOON. FEEL THERE WILL BE A WEAKENING TREND BY EVENING WITH RAINFALL RATES LOWERING AS THE REGION WILL BE BETWEEN IMPULSES. ANOTHER ROUND OF HEAVIER RAIN LOOKS TO ORGANIZE OVERNIGHT FRIDAY INTO SATURDAY MORNING AS ANOTHER IMPULSE EJECTS AHEAD OF THE PARENT CUT-FF LOW AND H5 TO H3 WIND SPEEDS INCREASE. GLOBAL MODELS ALONG WITH THE NAM SUGGEST THE HEAVIEST AXIS WILL BE EITHER ALONG THE I-35 CORRIDOR OR JUST SOUTHEAST. THIS BANDING OF SHOWERS AND THUNDERSTORMS WILL LIKELY BE TAPPING INTO PWATS OF 1.5" TO 1.8" AND FEEL THIS TIME FRAME FROM 1AM SATURDAY MORNING TO EARLY AFTERNOON WILL BE OF HIGH CONCERN DEPENDING ON EXACT EVOLUTION AND GEOGRAPHICAL PLACEMENT FOR FLOODING ISSUES. FINALLY...A DEVELOPING SURFACE LOW WILL HELP DRIVE THE FRONT THROUGH THE AREA LATE SATURDAY INTO EARLY SUNDAY AND HELP SLOWLY DIMINISH RAIN/TSTORM CHANCES AS THE MID LEVEL LOW SHIFTS EAST ACROSS NE TEXAS. LONG TERM (SATURDAY NIGHT THROUGH THURSDAY)... NO IMPACTS TO HIGHLIGHT FOR THE LONG TERM AS MUCH DRIER CONDITIONS ARE EXPECTED MONDAY THROUGH AT LEAST WEDNESDAY BEFORE ANOTHER FRONT POSSIBLY MOVES THROUGH ON THURSDAY OF NEXT WEEK. AN AXIS OF HIGH PRESSURE AND BELOW 0.9" PWATS WILL KEEP ATMOSPHERE STABILIZED AND DRY THROUGH THE EARLY AND MID PORTIONS OF NEXT WEEK WITH THE JET STREAM SHIFTING NORTH. THE SOUTHERN BRANCH OF THE JET STREAM LOOKS TO RELAX SLIGHTLY WITH ONLY A WEAK TROUGH NOTED ACROSS NORTHERN MEXICO BY WEDNESDAY. HOWEVER...GLOBAL MODELS SUGGEST THAT STRONGER NORTHERN STREAM TROUGHING COULD HELP BUCKLE THE SOUTHERN BRANCH ONCE GAIN AND FORCE ANOTHER CUT-OFF LOW SITUATION BY NEXT WEEKEND. TEMPERATURES WILL BE NEAR NORMAL FOR THIS TIME OF YEAR THROUGH THE WEEK. /ALLEN/ && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 72 58 66 58 74 / 100 100 90 70 20 AUSTIN BERGSTROM INTL AIRPORT 72 59 65 58 73 / 100 100 100 70 20 NEW BRAUNFELS MUNI AIRPORT 74 60 67 58 76 / 90 100 100 60 20 BURNET MUNI AIRPORT 67 55 63 56 71 / 100 80 80 70 20 DEL RIO INTL AIRPORT 70 59 69 56 79 / 100 80 80 30 10 GEORGETOWN MUNI AIRPORT 70 57 64 57 72 / 100 100 90 70 20 HONDO MUNI AIRPORT 73 60 68 57 77 / 100 90 90 50 20 SAN MARCOS MUNI AIRPORT 73 60 66 57 75 / 90 100 100 70 20 LA GRANGE - FAYETTE REGIONAL 75 62 68 60 74 / 90 100 100 70 20 SAN ANTONIO INTL AIRPORT 75 60 67 59 76 / 90 100 90 60 20 STINSON MUNI AIRPORT 74 60 68 59 77 / 90 100 90 60 20 && .EWX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH FROM 1 PM CDT THIS AFTERNOON THROUGH SATURDAY EVENING FOR THE FOLLOWING COUNTIES: ATASCOSA...BANDERA...BASTROP... BEXAR...BLANCO...BURNET...CALDWELL...COMAL...DE WITT...DIMMIT... EDWARDS...FAYETTE...FRIO...GILLESPIE...GONZALES...GUADALUPE... HAYS...KARNES...KENDALL...KERR...KINNEY...LAVACA...LEE...LLANO... MAVERICK...MEDINA...REAL...TRAVIS...UVALDE...VAL VERDE... WILLIAMSON...WILSON...ZAVALA. && $$ MESOSCALE/AVIATION...04 SYNOPTIC/GRIDS...15
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
425 AM CDT FRI MAR 20 2015 .SHORT TERM (TODAY THROUGH SATURDAY)... ...PERIODS OF HEAVY RAINFALL EXPECTED TODAY INTO SATURDAY... MAIN FOCUS NEXT 48 HOURS WILL CENTER AROUND MODERATE TO HEAVY RAIN THAT WILL LIKELY CAUSE LOCALIZED TO AREAS OF FLASH FLOODING IMPACTS WITH WIDESPREAD 2-4 INCHES WITH LOCALLY HIGHER AMOUNTS UP TO 6 INCHES CONFINED TO NARROW AXES. HAVE UPDATED THE FLASH FLOOD WATCH TO INCLUDE ALL AREAS WEST TO THE RIO GRANDE AND HAVE MOVED UP THE START TIME TO 1PM THIS AFTERNOON. A SEGMENTED WATCH COULD HAVE BEEN MADE BUT DECIDED TO KEEP THE MESSAGING AS SIMPLE AS POSSIBLE. THE UPDATED FLASH FLOOD WATCH WILL BE POSTED BY 6AM THIS MORNING. THE WATCH WAS EXTENDED WESTWARD GIVEN NEW HI-RES ARW/NMM SUPPORT AND A BULLISH HRRR THROUGH THE EARLY TO MID AFTERNOON HOURS. IN ADDITION...THE RUN TO RUN CONSISTANCY OF THE ECMWF CONTINUES TO HIGHLIGHT VAL VERDE COUNTY AND SURROUNDING AREAS FOR HIGHER TOTALS WHERE LIMITED SOIL DEPTH WITH COMPOUND FLOODING ISSUES QUICKLY. AT THIS TIME...A COLD FRONT IS LOCATED ALONG A LINE FROM SAN ANGELO TOWARD FORTH WORTH AND MOVING SOUTH. SPC MESOANALYSIS IS INDICATING STRONGER MID AND UPPER LEVEL DIVERGENCE OVERSPREADING THE BIG BEND OF TEXAS AND COUPLED WITH THE LOW-LEVEL FRONTAL CONVERGENCE...IS AIDING ELEVATED THUNDERSTORM DEVELOPMENT ACROSS WEST-CENTRAL TEXAS. THE BOUNDARY WILL CONTINUE SOUTH AND AS ADDITIONAL SYNOPTIC LIFT SHIFTS NORTHEAST FROM A WEAK EJECTING SHORTWAVE TROUGH...FURTHER SHOWER AND THUNDERSTORM DEVELOPMENT IS EXPECTED THROUGH THE MORNING HOURS FOR THE EDWARDS PLATEAU INTO THE RIO GRANDE VALLEY. THIS ACTIVITY IS EXPECTED TO PROGRESS SOUTH AND EAST THROUGH MID-DAY INTO THE I-35 CORRIDOR AND SE AREAS BY LATE AFTERNOON. WITH SUBTLE MID LEVEL HEIGHT FALLS AIDING IN MID LEVEL COOLING...ELEVATED INSTABILITY WILL RANGE FROM 300 J/KG IN HILL COUNTRY TO NEAR 1000 J/KG ALONG AN AXIS EXTENDING FROM THE RIO GRANDE NE TOWARDS THE 35 CORRIDOR AND POINTS SOUTHEAST. FEEL THIS AREA WHERE BEST ELEVATED INSTABILITY COMBINED WITH STRONGEST LOW-LEVEL CONVERGENCE EXISTS WILL LIKELY SEE THE HEAVIER RAINFALL TOTALS THROUGH THIS AFTERNOON. FEEL THERE WILL BE A WEAKENING TREND BY EVENING WITH RAINFALL RATES LOWERING AS THE REGION WILL BE BETWEEN IMPULSES. ANOTHER ROUND OF HEAVIER RAIN LOOKS TO ORGANIZE OVERNIGHT FRIDAY INTO SATURDAY MORNING AS ANOTHER IMPULSE EJECTS AHEAD OF THE PARENT CUT-FF LOW AND H5 TO H3 WIND SPEEDS INCREASE. GLOBAL MODELS ALONG WITH THE NAM SUGGEST THE HEAVIEST AXIS WILL BE EITHER ALONG THE I-35 CORRIDOR OR JUST SOUTHEAST. THIS BANDING OF SHOWERS AND THUNDERSTORMS WILL LIKELY BE TAPPING INTO PWATS OF 1.5" TO 1.8" AND FEEL THIS TIME FRAME FROM 1AM SATURDAY MORNING TO EARLY AFTERNOON WILL BE OF HIGH CONCERN DEPENDING ON EXACT EVOLUTION AND GEOGRAPHICAL PLACEMENT FOR FLOODING ISSUES. FINALLY...A DEVELOPING SURFACE LOW WILL HELP DRIVE THE FRONT THROUGH THE AREA LATE SATURDAY INTO EARLY SUNDAY AND HELP SLOWLY DIMINISH RAIN/TSTORM CHANCES AS THE MID LEVEL LOW SHIFTS EAST ACROSS NE TEXAS. && .LONG TERM (SATURDAY NIGHT THROUGH THURSDAY)... NO IMPACTS TO HIGHLIGHT FOR THE LONG TERM AS MUCH DRIER CONDITIONS ARE EXPECTED MONDAY THROUGH AT LEAST WEDNESDAY BEFORE ANOTHER FRONT POSSIBLY MOVES THROUGH ON THURSDAY OF NEXT WEEK. AN AXIS OF HIGH PRESSURE AND BELOW 0.9" PWATS WILL KEEP ATMOSPHERE STABILIZED AND DRY THROUGH THE EARLY AND MID PORTIONS OF NEXT WEEK WITH THE JET STREAM SHIFTING NORTH. THE SOUTHERN BRANCH OF THE JET STREAM LOOKS TO RELAX SLIGHTLY WITH ONLY A WEAK TROUGH NOTED ACROSS NORTHERN MEXICO BY WEDNESDAY. HOWEVER...GLOBAL MODELS SUGGEST THAT STRONGER NORTHERN STREAM TROUGHING COULD HELP BUCKLE THE SOUTHERN BRANCH ONCE GAIN AND FORCE ANOTHER CUT-OFF LOW SITUATION BY NEXT WEEKEND. TEMPERATURES WILL BE NEAR NORMAL FOR THIS TIME OF YEAR THROUGH THE WEEK. /ALLEN/ && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 72 58 66 58 74 / 80 100 90 70 20 AUSTIN BERGSTROM INTL AIRPORT 72 59 65 58 73 / 80 100 100 70 20 NEW BRAUNFELS MUNI AIRPORT 74 60 67 58 76 / 70 100 100 60 20 BURNET MUNI AIRPORT 67 55 63 56 71 / 80 80 80 70 20 DEL RIO INTL AIRPORT 70 59 69 56 79 / 80 80 80 30 10 GEORGETOWN MUNI AIRPORT 70 57 64 57 72 / 80 100 90 70 20 HONDO MUNI AIRPORT 73 60 68 57 77 / 80 90 90 50 20 SAN MARCOS MUNI AIRPORT 73 60 66 57 75 / 70 100 100 70 20 LA GRANGE - FAYETTE REGIONAL 75 62 68 60 74 / 70 100 100 70 20 SAN ANTONIO INTL AIRPORT 75 60 67 59 76 / 70 100 90 60 20 STINSON MUNI AIRPORT 74 60 68 59 77 / 70 100 90 60 20 && .EWX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH FROM 1 PM CDT THIS AFTERNOON THROUGH SATURDAY EVENING FOR THE FOLLOWING COUNTIES: ATASCOSA...BANDERA...BASTROP... BEXAR...BLANCO...BURNET...CALDWELL...COMAL...DE WITT...DIMMIT... EDWARDS...FAYETTE...FRIO...GILLESPIE...GONZALES...GUADALUPE... HAYS...KARNES...KENDALL...KERR...KINNEY...LAVACA...LEE...LLANO... MAVERICK...MEDINA...REAL...TRAVIS...UVALDE...VAL VERDE... WILLIAMSON...WILSON...ZAVALA. && $$ MESOSCALE/AVIATION...04 SYNOPTIC/GRIDS...15
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
203 AM EDT FRI MAR 20 2015 .SYNOPSIS... LOW PRESSURE WILL SLIDE OT THE NORTH CAROLINA COAST BY FRIDAY MORNING THEN HEAD NORTH ALONG INTO FRIDAY EVENING. HIGH PRESSURE BUILDS INTO THE AREA FOR THE WEEKEND. && .NEAR TERM /THROUGH TODAY/... AS OF 1130 PM EDT THURSDAY... MAIN ISSUE OVERNIGHT WILL BE THE TYPE OF PRECIP FALLING NORTH OF A LWB-LYH LINE...MAINLY HIGHER TERRAIN. MODELS ESPECIALLY THE NAM IS SHOWING MIX OF SNOW/SLEET THRU MORNING IN THE ALLEGHANY HIGHLANDS...AND BASED ON SFC OBS AND DUAL POL RADAR ANALYSIS WITH CURRENT CONDITIONS...THE NAM IS DOING A PRETTY DECENT JOB. TEMPS HAVE BEEN SLOW TO RISE...AND MOST CASES NOT REALLY MOVING AT ALL. BLACKSBURG HAS BEEN STUCK AT 32-33F FOR THE PAST 6-8 HOURS. LOOKING AT RADAR...THE LATEST HRRR STILL DOING A FAIRLY DECENT JOB WITH LOCATION AND WILL FOLLOW IT BUT RAISE POPS A LITTLE HIGHER TO ACCOUNT FOR OVERSHOOTING LIGHT RAIN/DRIZZLE. STILL MOST AREAS SOUTH OF A MKJ-AVC WHICH IS MARION/WYTHEVILLE TO SOUTH HILL VA WILL SEE LIGHT RAIN/DRIZZLE AND FOG THROUGH MOST OF THE NIGHT WHILE BETTER QPF OCCURS NORTH...AND MORESO FROM BKW-LYH NORTH. SNOW/SLEET AMOUNTS OVERNIGHT WILL BE SMALL UP TO AN INCH IN THE ALLEGHANYS ABOVE 3000 FT. SHOULD SEE THINGS TO SLOWLY TAPER OFF TO DZ/--RA ONCE THE MAIN OVERRUNNING AND LIFT SHIFT EAST AND NORTH TOWARD THE COAST AND NRN VA BY MORNING. ADDED FOG TO MOST OF OUR RIDGES AND ESPECIALLY BLUE RIDGE. PREVIOUS VALID DISCUSSION... BY FRIDAY MORNING...LOW WILL BE NEAR ILM NC...AND THEN PROGRESS NE THRU THE DAY. CONCURRENTLY...ANOTHER AREA OF LOW PRESSURE WILL BE PROGRESSING EASTWARD THROUGH THE OHIO VALLEY. ITS ASSOCIATED COLD FRONT WILL PROGRESS ACROSS THE AREA FRIDAY AFTERNOON. UNTIL THAT TIME...EXPECT THE COLD AIR DAMMING WEDGE TO HOLD FAST ACROSS THE REGION...WITH PLENTY OF CLOUD COVER. PRECIPITATION WILL GRADUALLY DECREASE IN COVERAGE ACROSS THE AREA FRIDAY MORNING WITH THE DEPARTURE OF THE COASTAL LOW. HOWEVER...LOOK FOR A RESURGENCE IN THE WEST AS THE COLD FRONT CROSSES THE AREA. FRIDAY AFTERNOON...PRECIPITATION IS EXPECTED TO BE LACKING EAST OF THE BLUE RIDGE AS DOWNSLOPE WINDS SUPPRESS THE ACTIVITY. TEMPERATURES WILL BE SLOW TO RISE WHILE THE COLD AIR DAMMING IS STILL IN PLACE. IRONICALLY...IT WILL TAKE THE COLD FRONT TO HELP MIX THE LOWER ATMOSPHERE AND START TO THIN OUT THE CLOUD COVER A BIT IN THE EAST TO HELP TEMPERATURES RISE ON FRIDAY. HIGHS ARE EXPECTED TO RANGE FROM THE UPPER 40S TO AROUND 50 ACROSS THE MOUNTAINS...TO THE 50S ACROSS THE PIEDMONT. && .SHORT TERM /TONIGHT THROUGH SUNDAY/... AS OF 310 PM EDT THURSDAY... CONFLUENT FLOW ALOFT AND DRIER AIR BEHIND THE COLD FRONT FRIDAY AND SATURDAY. ANY PRECIPITATION THAT IS LEFT OVER LATE IN THE DAY ON FRIDAY WILL QUICKLY DISSIPATE FRIDAY EVENING. A COLD FRONT WILL COME THROUGH SATURDAY. NO PRECIPITATION IS EXPECTED ALONG THIS BOUNDARY. HAVE PROBABILITY OF PRECIPITATION MOVING BACK INTO THE SOUTHERN COUNTY WARNING AREA ON SUNDAY WITH THE APPROACH OF A WEAKENING SOUTHERN STREAM SHORT WAVE. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 1205 PM EDT THURSDAY... SPLIT FLOW WITH BROAD EASTERN UNITED STATES TROF ON MONDAY TRANSITIONS TO A WESTERN TROF AND RIDGING OVER THE EAST ON WEDNESDAY AND THURSDAY. SOUTHERN STREAM SYSTEM REMAINS SUPPRESSED ON SUNDAY NIGHT AND MONDAY WITH A MAJORITY OF THE HEAVIER PRECIPITATION ACROSS THE SOUTHEAST UNITED STATES. SOME WINTER PRECIPITATION MAY BE POSSIBLE ON THE NORTHERN FRINGE OF THIS SYSTEM. THIS WILL DEPEND ON HOW FAR COLDER AIR AND HIGH PRESSURE WEDGES DOWN INTO THE MID ATLANTIC REGION. CENTER OF HIGH PRESSURE WILL BE IN A FAVORABLE POSITION FOR A WEDGE ON MONDAY. CAD WILL ALSO BE ENHANCED BY INVERTED TROFFING WEST OF THE APPALACHIANS. SOME SHORT WAVE ENERGY COMING THROUGH THE NORTHERN STREAM ON TUESDAY MAY IMPACT THE FORECAST AREA. THERE WILL ALSO BE A WARMING TREND ON WEDNESDAY AND THURSDAY IN ADVANCE OF THE NEXT SIGNIFICANT COLD FRONT. ECMWF SHOWED SOME INDICATIONS OF A CHANCE OF PRECIPITATION IN ASSOCIATION WITH A WARM FRONT ON WEDNESDAY. SURFACE HIGH PRESSURE MOVES OFFSHORE BY WEDNESDAY WITH DEEP MOISTURE COMING OUT OF THE GULF AHEAD OF THE COLD FRONT. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... AS OF 200 AM EDT FRIDAY... CLASSIC WEDGE SCENARIO CURRENTLY IN PLACE WITH HIGH PRESSURE CENTERED OVER THE NORTHEAST SURGES DOWN THE EASTERN SEABOARD BANKED UP AGAINST THE APPALACHIANS. LOW PRESSURE TO OUR WEST IS PUSHING WARM AND MOIST AIR UP AND OVER THE WEDGE AND THIS ISENTROPIC LIFT IS GENERATING WIDESPREAD LOW CIGS AND LIGHT PRECIPITATION. THE WEDGE WILL LIKELY PERSIST THROUGH AT LEAST EARLY AFTERNOON FRIDAY RESULTING IN PERSISTENT LOW CIGS IN ADDITION TO AREAS OF LIGHT RAIN OR DRIZZLE. THROUGH NOON TODAY EXPECT AREAS OF IFR/LIFR CONDITIONS DUE TO LOW CLOUDS AND FOG. AFTER NOON...WINDS ARE EXPECTED TO SHIFT AROUND MORE FROM A WESTERLY DIRECTION ALLOWING FOR GRADUAL IMPROVEMENT OF CIGS/VSBYS...MOST READILY EAST OF THE BLUE RIDGE AS NW FLOW DOWNSLOPE KICKS IN...BUT SLOWER IMPROVEMENT CAN BE EXPECTED WEST OF THE RIDGE AS NW FLOW IS UPSLOPE AND SOME LIGHT SHOWERS/DRIZZLE LINGER THROUGH THE AFTERNOON. GENERALLY LIGHT WINDS OVERALL EXCEPT GUSTY NEAR RIDGE CRESTS. EXTENDED FORECAST...HIGH PRESSURE BUILDS ACROSS THE MID ATLANTIC FOR THE WEEKEND...ALLOWING FOR RETURN TO MAINLY VFR CONDITIONS. MVFR AND A CHANCE OF PRECIPITATION WILL RETURN BY SUNDAY NIGHT AS A BACKDOOR COLD FRONT MARKS THE ARRIVAL OF ANOTHER WEDGE EARLY NEXT WEEK. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...DS/WP SHORT TERM...AMS LONG TERM...AMS AVIATION...PM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1042 PM CDT SAT MAR 21 2015 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SHORT TERM...TONIGHT AND SUNDAY ISSUED AT 207 PM CDT SAT MAR 21 2015 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW CANADIAN HIGH PRESSURE BUILDING SOUTHEAST ACROSS THE NORTHERN MISSISSIPPI VALLEY AND WESTERN GREAT LAKES REGION. CLOUDS OFF LAKE SUPERIOR ARE RETREATING EARLY THIS AFTERNOON AS DRY AIR ALOFT MIXES DOWN. MEANWHILE...A WIDE SWATH OF MID-CLOUDS IN A CONFLUENT/FRONTOGENETICAL AREA IS STREAMING SOUTHEAST OVER THE NORTHERN PLAINS AND POISED TO ARRIVE LATER TODAY. CLOUD TRENDS AND TEMPS ARE THE MAIN FORECAST CONCERNS OVER THE NEXT 24 HOURS. TONIGHT...CANADIAN HIGH PRESSURE WILL BE BUILDING SOUTHEAST ACROSS THE STATE OF WISCONSIN. DESPITE THE INCOMING SURFACE HIGH...LAKE CLOUDS MAY LINGER OVER THE DOOR PENINSULA AS A RESULT OF WINDS TURNING TO THE EAST AND 925MB TEMPS AROUND -11C. LIGHT NORTHERLY FLOW AND INCREASING INSTABILITY MAY ALSO BRING LAKE CLOUDS INTO VILAS COUNTY LATE TONIGHT. OTHERWISE WILL SEE 700MB CONVERGENCE BRING IN A BAND OF MID-CLOUD ACROSS MUCH OF THE AREA. EDGE THE NORTHERN EXTENT OF THESE CLOUDS SLIGHTLY FURTHER NORTH BASED ON THE LATEST GUIDANCE AND SATELLITE TRENDS...AND CONSEQUENTLY...RAISED MIN TEMPS SLIGHTLY FARTHER NORTH AS WELL. LOWS RANGING FROM THE SINGLE DIGITS AT LAND O LAKES TO THE MIDDLE 20S SOUTH. SUNDAY...THE MID-LEVEL CONVERGENCE ZONE WILL SINK SLIGHTLY SOUTH THROUGH THE DAY WHICH SHOULD LEAD TO CLEARING OVER NORTHEAST WISCONSIN. ANY LOW CLOUDS OVER N-C WISCONSIN SHOULD MIX OUT WITH DAYTIME HEATING BY MIDDAY. THEN WILL BE WATCHING AN INVERTED TROUGH/SHORTWAVE MOVE EAST ACROSS THE NORTHERN MISSISSIPPI VALLEY DURING THE AFTERNOON. AHEAD OF THESE FEATURES...A BAND OF LIGHT PRECIP WILL BE DEVELOPING AS IT PUSHES EAST ACROSS CENTRAL MINNESOTA AND WESTERN WISCONSIN. MOST GUIDANCE INCLUDING THE NAM/SREF/AND MESOMODELS KEEP PRECIP SOUTHWEST OF THE FORECAST AREA AND THAT PLACEMENT COINCIDES BETTER WITH THE FRONTOGENETICAL FORCING. NORTHEAST WINDS WILL KEEP HIGHS COOL AND WILL GO WITH MAX TEMPS MAINLY IN THE MID TO UPPER 30S. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY ISSUED AT 207 PM CDT SAT MAR 21 2015 MAIN CONCERN FOR THIS PERIOD WILL BE SYSTEM SUNDAY NIGHT...A SECOND SYSTEM TUESDAY NIGHT INTO WEDNESDAY AND BELOW NORMAL TEMPERATURES FOR THE LATTER HALF OF NEXT WEEK INTO NEXT WEEKEND. SYSTEM FOR SUNDAY NIGHT APPEARS TO BE LOCKED IN NOW...WITH CHANCES OF LIGHT SNOW SOUTH OF A KEWAUNEE TO TOMAHAWK LINE. WILL BE FAIRLY SHARP GRADIENT IN THE SNOW CHANCES WITH THE HIGHEST CHANCES ACROSS CENTRAL WISCONSIN. SNOWFALL AMOUNTS ACROSS PORTIONS OF PORTAGE... WOOD..AND WAUSHARA COUNTIES COULD BE AROUND AN INCH. ONLY SNOW FLURRIES WILL BE SEEN AT GREEN BAY. EXCEPT FOR A FEW LINGERING FLURRIES MONDAY MORNING ACROSS THE FAR SOUTH...DRY CONDITIONS WILL PREVAIL MONDAY AFTERNOON INTO MONDAY EVENING. LATEST DEVELOP TODAY IS THAT SOME OF THE MODELS ARE PRODUCING LIGHT PRECIPITATION AMOUNTS ACROSS THE NORTH WITH RETURN FLOW. DID ADD SOME FLURRIES LATE MONDAY NIGHT TO ACCOUNT FOR THIS SCENARIO. MAIN SYSTEM STILL ON TRACK FOR TUESDAY NIGHT AND WEDNESDAY. BOUNDARY/850MB TEMPERATURES STILL PROBLEMATIC WITH PRECIPITATION TYPES AND SNOW AMOUNTS. ALTHOUGH NOT IN THE FORECAST...COULD BE A LITTLE SLEET OR FREEZING RAIN MIXED IN AT TIMES ACROSS THE NORTH. WITH SUCH UNCERTAINTIES IN THE FORECAST...DID NOT ADD TO THE FORECAST AT THIS TIME. SOME LINGERING LIGHT RAIN OR SNOW SHOWERS COULD LINGER INTO THURSDAY WITH COLD CYCLONIC FLOW ALOFT. WESTERN RIDGE WILL BUILD BY THE END OF NEXT WEEK...WHICH WILL LEAD TO BELOW NORMAL TEMPERATURES INTO NEXT WEEKEND. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1042 PM CDT SAT MAR 21 2015 MAINLY A VFR MID LEVEL CIG WILL PASS OVER THE AREA TONIGHT INTO SUNDAY MORNING. DRIER AIR FROM THE NORTH WILL PRODUCE MORE OF A MIX OF MID TO HIGH LEVEL CLOUDS LATER SUNDAY. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......ECKBERG AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
902 PM CDT SAT MAR 21 2015 .UPDATE... ISSUED AT 902 PM CDT SAT MAR 21 2015 THE MAIN FOCUS IS ON THE SNOW FOR TOMORROW IN REGARD TO WHEN IT WILL START AND WHETHER IT WILL START OUT AS RAIN OR SNOW. VERY DRY AIR IN PLACE IN THE LOW LEVELS THANKS TO NORTHEASTERLY FLOW ALONG THE SOUTHERN PERIPHERY OF A RIDGE OF HIGH PRESSURE. HIGH CLOUDS ARE MOVING IN AND WILL THICKEN THROUGH THE NIGHT. AS WE APPROACH DAYBREAK TOMORROW MORNING MUCH OF THE MESO-GUIDANCE...SUCH AS THE RAP/HRRR/HOPWRF...IS SUGGESTING THAT THE PRECIPITATION WILL BE KNOCKING ON THE DOOR OF SOUTHEAST MINNESOTA. AS THE SYSTEM MOVES INTO THE REGION TOMORROW AFTERNOON...LIFT WILL BE MAXIMIZED AND THE PRECIPITATION WILL BECOME MORE WIDESPREAD AND INTENSE. MANY OF THE RAP FORECAST SOUNDINGS FOR TOMORROW MORNING SHOW THAT AS THE PROFILE BECOMES SATURATED...THE SURFACE/LOW LEVEL WET BULB TEMPERATURES SHOULD BE COLD ENOUGH TO PRODUCE ALL SNOW. SHOULD AIR TEMPERATURES STAY A BIT ON THE WARMER SIDE...IT COULD START AS RAIN...BUT AM LEANING MORE TOWARD THE IDEA THAT SNOW IS THE MORE LIKELY PRECIPITATION TYPE. IF THAT IS THE CASE...OUR FORECAST SNOW AMOUNTS WILL LIKELY NEED TO BE UPPED IN THE MORNING/AFTERNOON TOMORROW. THE RAP CAN TEND TO GO TOO LOW UNDER THE PRECIPITATION SHIELD...SO CONFIDENCE WAS NOT HIGH ENOUGH TO PUSH THE FORECAST THAT WAY...PARTICULARLY SINCE SURFACE TEMPERATURES ARE STILL IN THE MID TO UPPER 30S THROUGH MUCH OF THE AREA. THE OTHER QUESTION IS WITH ROAD TEMPERATURES AND HOW WARM THEY WILL BE TOMORROW. TODAY...UNDER MAINLY FULL SUN...THEY REACHED THE 50S/60S AND CURRENTLY ARE IN THE 40S. WITH HEAVY ENOUGH OF SNOW RATES IN THE AFTERNOON/EVENING TOMORROW...EXPECT THAT SNOW WILL BE ABLE TO ACCUMULATE ON THE ROADS AND CAUSE SOME SLICK CONDITIONS. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 349 PM CDT SAT MAR 21 2015 THE FOCUS FOR THIS PERIOD IS ON THE SYSTEM COMING THROUGH FOR SUNDAY AND SUNDAY NIGHT. WATER VAPOR SATELLITE SHOWS A COUPLE OF SHORT WAVE TROUGHS OVER THE PACIFIC NORTHWEST THIS AFTERNOON. THE FIRST WAS OVER THE ROCKIES OF NORTHERN IDAHO/NORTHWEST MONTANA WITH THE SECOND OVER WASHINGTON STATE. THE 21.12Z MODELS ALL HANDLE THESE WAVES SIMILARLY WITH THE LEAD WAVE OVER IDAHO/MONTANA THE MAIN PLAYER AS IT COMES ACROSS THE UPPER MIDWEST AND THE GREAT LAKES REGION WHILE THE SECOND WAVE GOES ACROSS SOUTHERN CANADA. THIS FIRST WAVE DOES NOT BECOME ALL THAT STRONG BUT ENOUGH TO PRODUCE SOME WEAK PV ADVECTION IN THE 500-300 MB LAYER SUNDAY AFTERNOON AND EVENING. THE UPPER LEVEL JET WILL ALSO BE ASSOCIATED WITH THIS WAVE WITH THE AREA COMING UNDER THE RIGHT ENTRANCE REGION AND ITS ASSOCIATED VERTICAL MOTIONS. IN THE LOW LEVELS...STILL EXPECTING A STRONG LOW LEVEL BAROCLINIC ZONE TO BE SET UP FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA. WEAK TO AT TIMES MODERATE FRONTOGENESIS WILL OCCUR OVER THE BAROCLINIC ZONE...ESPECIALLY IN THE 750-650 MB LAYER. THE ISENTROPIC UP GLIDE WILL BE ON THE ORDER OF 2 TO 4 UBAR/S ON THE 285K SURFACE SUNDAY EVENING. EXPECTING THAT ALL THIS FORCING WILL BE SUFFICIENT TO PRODUCE A BAND OF PRECIPITATION RIGHT ACROSS THE FORECAST AREA FROM NORTHWEST TO SOUTHEAST. WILL SHOW AN AREA OF 80 TO 100 PERCENT PRECIPITATION CHANCES STARTING ACROSS SOUTHEAST MINNESOTA BY LATE MORNING OR EARLY AFTERNOON AND SPREADING INTO WESTERN WISCONSIN BY LATE AFTERNOON INTO THE EVENING. PRECIPITATION TYPES REMAIN A CONCERN THROUGHOUT THE EVENT WITH THIS SYSTEM. EXPECTING THAT IT SHOULD INITIALLY START OUT AS SOME LIGHT RAIN. HOWEVER...WHEN THE BEST FORCING OCCURS...THE BUFKIT SOUNDINGS FROM BOTH THE NAM AND GFS SHOW STRONG LIFT THROUGH THE DENDRITIC GROWTH ZONE THAT SHOULD BE ABLE TO PRODUCE GOOD SNOW RATES AND CHANGE THE PRECIPITATION OVER TO ALL SNOW DESPITE THE BOUNDARY LAYER INITIALLY BEING ABOVE FREEZING. ALSO...THE LOW LEVEL FLOW WILL BE OUT OF THE EAST AND ALTHOUGH THIS WILL BE TRYING TO BRING SOME DRIER AIR...THIS DRIER AIR MAY HELP TO PUSH THE WET BULB ZERO TEMPERATURES DOWN AND AID IN THE TRANSITION TO ALL SNOW. THERE ALSO IS STILL SOME CONCERN ABOUT A LOSS OF ICE IN THE CLOUDS AS THE FORCING STARTS TO DIMINISH ON THE BACK SIDE OF THE PRECIPITATION BAND. WHILE THE MODELS HAVE BEEN CONSISTENT IN SHOWING THIS...THEY HAVE NOT BEEN CONSISTENT ON THE TIMING OF WHEN THE ICE COULD BE LOST WITH EACH MODEL RUN SHOWING THE ICE REMAINING LONGER. WILL STILL SHOW A CHANGE OVER TO FREEZING RAIN...BUT CONFIDENCE ON THIS CONTINUES TO BE LOW. WILL ISSUE A WINTER WEATHER ADVISORY FOCUSING ON THE BAND OF HEAVIER SNOW ACCUMULATIONS...GENERALLY IN THE 2 TO 4 INCH RANGE. STILL START THIS LATE SUNDAY MORNING ACROSS SOUTHEAST MINNESOTA INTO FAR WESTERN WISCONSIN AND RUN THIS THROUGH SUNDAY EVENING. WILL HAVE THE ADVISORY ALONG THE MISSISSIPPI RIVER INTO SOUTHWEST WISCONSIN FROM ABOUT THE MIDDLE OF SUNDAY AFTERNOON THROUGH SUNDAY NIGHT. THIS MAY HAVE TO BE EXPANDED LATER TO COVER THE ICING POTENTIAL...BUT CONFIDENCE ON THIS ASPECT OF THE FORECAST REMAINS TOO LOW TO ISSUE HEADLINES ON AT THIS TIME. .LONG TERM...(TUESDAY THROUGH SATURDAY) ISSUED AT 349 PM CDT SAT MAR 21 2015 ANOTHER SHORT WAVE COMING IN OVER THE PACIFIC NORTHWEST COAST WILL CROSS THE NORTHERN ROCKIES AND THEN IS EXPECTED TO DEEPEN OVER THE UPPER MIDWEST TUESDAY. THE MODELS ARE STILL BOUNCING AROUND WITH WHETHER THIS SYSTEM WILL COME THROUGH PHASED WITH ANOTHER NORTHERN STREAM SHORT WAVE TROUGH LIKE THE GFS SHOWS...OR WHETHER THE TWO SYSTEMS WILL REMAIN SEPARATE LIKE THE ECMWF AND GEM. EITHER WAY...ALL THE MODELS SHOW ONE AREA OF SURFACE LOW PRESSURE TRACKING ACROSS OR JUST NORTH OF THE FORECAST AREA WITH THE ECMWF AND GEM HAVING ANOTHER SURFACE LOW FARTHER NORTH UNDER THE OTHER SHORT WAVE TROUGH. EITHER OF THESE SOLUTIONS SHOULD ALLOW ENOUGH WARM AIR TO BE DRAWN IN FOR THIS SYSTEM TO PRIMARILY PRODUCE RAIN. THE TIMING LOOKS TO HAVE THE PRECIPITATION MOVING IN TUESDAY AFTERNOON WITH THE BEST CHANCES TUESDAY NIGHT...70 TO 80 PERCENT FOR THE ENTIRE AREA...AND THEN MOVES OUT WEDNESDAY AND WEDNESDAY NIGHT. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 649 PM CDT SAT MAR 21 2015 THE MAIN FOCUS AT THE TAF SITES IS WITH THE SNOW THAT WILL MOVE IN TOMORROW MORNING/AFTERNOON. AHEAD OF IT...HIGH LEVEL CLOUD COVER IS MOVING IN FROM THE NORTHWEST WITH CEILINGS DROPPING THROUGH TOMORROW MORNING AS THE DEPTH OF MID LEVEL MOISTURE INCREASES AHEAD OF THE NEXT SYSTEM. SNOW IS EXPECTED TO MOVE IN/DEVELOP ACROSS SOUTHEAST MINNESOTA TOMORROW MORNING BEFORE SPREADING EAST TOWARD LSE AROUND 1PM. SNOW MAY BE HEAVY AT TIMES...SO IFR TO LIFR CONDITIONS ARE EXPECTED WITH VISIBILITY LIKELY TO DROP TO A MILE OR LESS AT TIMES. THE HEAVIEST SNOW IS EXPECTED TO FALL TOMORROW AFTERNOON AND EVENING BEFORE DISSIPATING OVERNIGHT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY FROM 11 AM SUNDAY TO 1 AM CDT MONDAY FOR WIZ032-033. WINTER WEATHER ADVISORY FROM 3 PM SUNDAY TO 7 AM CDT MONDAY FOR WIZ041-053>055-061. MN...WINTER WEATHER ADVISORY FROM 11 AM SUNDAY TO 1 AM CDT MONDAY FOR MNZ079-086>088-094-095. WINTER WEATHER ADVISORY FROM 3 PM SUNDAY TO 7 AM CDT MONDAY FOR MNZ096. IA...WINTER WEATHER ADVISORY FROM 3 PM SUNDAY TO 7 AM CDT MONDAY FOR IAZ010-011. && $$ UPDATE...HALBACH SHORT TERM...04 LONG TERM...04 AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
400 AM EDT SUN MAR 22 2015 .SYNOPSIS... A LOW PRESSURE SYSTEM WILL DEVELOP ALONG THE GULF COAST AND BRING RAIN BACK TO THE AREA TODAY THROUGH MONDAY. COOLER TEMPERATURES WILL OCCUR. SURFACE RIDGE TO THE NORTH AND A WEAK TROUGH ALONG THE CAROLINA COAST WILL PERSIST THROUGH MIDWEEK. && .NEAR TERM /THROUGH TONIGHT/... WEAK SURFACE LOW DEVELOPING IN THE NORTHWEST GULF OF MEXICO. RADAR AT 0730Z INDICATING LIGHT RAIN MOVING ACROSS THE SAVANNAH RIVER INTO THE MIDLANDS FROM CENTRAL GEORGIA. LATEST HRRR RADAR SIMULATION APPEARS TO HAVE A HANDLE ON PRECIPITATION TREND. HRRR MODEL SPREADS LIGHT PRECIPITATION TO THE NORTH DURING THE MORNING AS MOISTURE FLUX/ISENTROPIC LIFT INCREASES. BASED ON RADAR/MODEL CONSENSUS...RAISED POPS ACROSS THE REGION. THE UPPER LEVEL TROUGH OVER THE SOUTHERN PLAINS WILL CONTINUE TO TRACK TO THE NORTHEAST TODAY...ACROSS THE MISSISSIPPI VALLEY THIS EVENING. INCREASING ISENTROPIC LIFT THIS AFTERNOON AND THIS EVENING. PRECIPITABLE WATER ABOVE CLIMATOLOGICAL MEAN WITH HIGHEST VALUES IN THE CSRA...AROUND 1.3 INCHES. AS UPPER LEVEL LOW MOVES OVER THE REGION TONIGHT...EXPECT STRONGEST LIFT DURING THIS TIME AND WILL MENTION POSSIBLE MODERATE RAIN MAINLY SOUTHERN AREAS. A TIGHT PRECIPITATION GRADIENT EXPECTED WITH STRONGEST 850MB CONVERGENCE ACROSS SOUTHERN MIDLANDS. LIGHTER AMOUNTS ACROSS NORTH MIDLANDS. WITH RAIN AND EXTENSIVE CLOUDS TEMPERATURES EXPECTED TO RISE A FEW DEGREES FROM MORNING LOWS...SO LOW TO MID 60S APPEARS ON TRACK. MOS CONSENSUS FOR MINIMUM TEMPERATURES HAS BEEN CONSISTENT AND APPEARS ACCEPTED. && .SHORT TERM /MONDAY THROUGH TUESDAY/... COLD AIR DAMMING/WEDGE APPEARS LIKELY MONDAY WITH WEAK ISENTROPIC LIFT/MOISTURE FLUX CONTINUING THROUGH AT LEAST 18Z. LIGHT PRECIPITATION OR DRIZZLE MAY CONTINUE THROUGH AFTERNOON. RAISED POPS ALL AREAS FROM PREVIOUS FORECAST. PREFER COOLER MAV GUIDANCE WHICH IS IN LINE WITH THE SREF AND LOCAL WEDGE GUIDANCE...SO LOW TO MID 50S WITH TEMPERATURES LIKELY FALLING THROUGH THE AFTERNOON AS RIDGE STRENGTHENS TO THE NORTH. WEAK ONSHORE FLOW MAY CONTINUE THROUGH TUESDAY...SO INCREASED CLOUDS WITH MODEST WARMING. SHOWERS APPEAR POSSIBLE MAINLY CLOSER TO THE COAST SO FOR NOW WILL LEAVE POPS BELOW 15 PERCENT. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... GENERAL AGREEMENT CONTINUES IN THE EXTENDED FORECAST PERIOD WITH THE OVERALL PATTERN...THOUGH THERE IS UNCERTAINTY LATE IN THE FORECAST DUE TO TIMING AND STRENGTH DIFFERENCES ASSOCIATED WITH A DEEP UPPER TROUGH DIGGING ACROSS THE MIDDLE PART OF THE COUNTRY. FOR THE MOST PART...USED A BLEND OF GFS/PREVIOUS ECMWF/HPC GUIDANCE. THERE IS UNCERTAINTY WITH POSSIBLE RAIN CHANCES WEDNESDAY AS A WEAK INVERTED TROUGH MAY DEVELOP ALONG THE COAST WITH THE SURFACE HIGH RETREATING IN ADVANCE OF THE NEXT STORM SYSTEM...ALTHOUGH THE COOL WEDGE MAY BE STRONGER THAN FORECAST. A DIGGING TROUGH ACROSS THE NORTHERN HALF OF THE COUNTRY THURSDAY INTO FRIDAY WILL RESULT IN INCREASING MOISTURE IN DEVELOPING SOUTHWESTERLY FLOW AHEAD OF AN APPROACHING COLD FRONT. FORECAST INSTABILITY OF LIFTED INDEX VALUES AROUND MINUS 2 THURSDAY AFTERNOON WOULD SUPPORT AN ISOLATED THUNDERSTORM THREAT. RAIN CHANCES CONTINUE INTO FRIDAY DUE TO TIMING ISSUES BETWEEN THE MODELS. AT THIS TIME SATURDAY APPEARS DRY WITH HIGH PRESSURE BUILDING IN FROM THE WEST. TEMPERATURES GENERALLY BELOW NORMAL TUESDAY...AOA NORMAL WEDNESDAY THROUGH FRIDAY...AND BELOW NORMAL SATURDAY. && .AVIATION /07Z SUNDAY THROUGH THURSDAY/... HIGH CONFIDENCE IN RESTRICTIONS BEGINNING AROUND DAYBREAK AND CONTINUING THROUGH THE END OF THE PERIOD. FRONTAL BOUNDARY FROM THE GULF COAST THROUGH SOUTHEASTERN GA CONTINUES TO MOVE NORTHWARD AND WILL SPREAD RAIN ACROSS THE TAF SITES THROUGH THE DAY. REGIONAL WSR-88D NETWORK CURRENTLY SHOWS RAIN MOVING THROUGH CENTRAL GA WITH SCATTERED RAIN ENTERING THE AGS/DNL AREA. EXPECT RAIN TO MOVE INTO THE TAF SITES THROUGH DAYBREAK ALONG WITH LOWERING CIGS AND VSBYS. EXPECT MVFR CONDITIONS THROUGH MUCH OF THE DAY WITH CONDITIONS LOWERING TO IFR FROM 23/00Z THROUGH THE END OF THE PERIOD. WINDS THROUGH THE PERIOD WILL BE EASTERLY AT 7 KNOTS OR LESS. EXTENDED AVIATION OUTLOOK...HIGH CONFIDENCE IN CIG/VSBY RESTRICTIONS CONTINUING THROUGH MONDAY NIGHT IN WEDGE CONDITIONS. THERE MAY BE ANOTHER CHANCE FOR RAIN AND ASSOCIATED RESTRICTIONS TUESDAY NIGHT THROUGH THURSDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSON KY
159 AM EDT SUN MAR 22 2015 .UPDATE... ISSUED AT 158 AM EDT SUN MAR 22 2015 UPDATED GRIDS WITH LATEST OBS AND TRENDS. DID KEPT GENERALLY TRENDS IN TEMPS AS IS AS DRY COLD FRONT CONTINUES TO PUSH THROUGH THE REGION TONIGHT. OPTED TO KEEP PATCHY VALLEY FOG ACROSS PORTIONS OF THE REGION GIVEN THAT EKQ SAW A SLIGHT DROP IN VIS AT 5Z. NO MAJOR CHANGES NEEDED THIS UPDATE. UPDATE ISSUED AT 1100 PM EDT SAT MAR 21 2015 HOURLY GRIDS HAVE BEEN UPDATED TO ACCOUNT FOR THE LATEST OBSERVATIONS AND THE DRY COLD FRONT CROSSING THE AREA. THIS FRONTAL PASSAGE SHOULD LEAD TO ENOUGH MIXING OF THE DECOUPLED VALLEYS IN THE SOUTHEAST FOR AT LEAST A COUPLE OF HOURS AS IT MOVES THROUGH...BEFORE TEMPS AGAIN DROP OFF LATE TONIGHT BEHIND THE FRONT. THE HOURLY TEMPERATURES HAVE BEEN BLENDED TO THE PREVIOUS CURVED AFTER 3 AM TO ACCOUNT FOR THIS EXPECTATION. UPDATE ISSUED AT 810 PM EDT SAT MAR 21 2015 HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND SATELLITE IMAGERY. THE COLD FRONT THAT IS LACKING IN LOW LEVEL MOISTURE IS DROPPING INTO THE NORTHERN PART OF THE CWA ATTM. THIS FRONT WILL DROP SOUTH ACROSS THE REMAINDER OF THE CWA DURING THE REST OF THIS EVENING AND INTO THE OVERNIGHT HOURS. THIS FRONT WILL BRING LITTLE MORE THAN A SHIFT IN WINDS FROM THE WEST OR SOUTHWEST TO THE NORTH AND NORTHEAST ON RIDGETOPS AND IN EXPOSED LOCATIONS. CIRRUS ASSOCIATED WITH A SHORTWAVE WORKING FROM THE SOUTHERN PLAINS TOWARD THE MS VALLEY REGION CONTINUES TO MOVE OVERHEAD AS IT WORKS AROUND RIDGING EXTENDING FROM THE GULF OF MEXICO INTO THE SOUTHEAST. THERE IS ADDITIONAL CIRRUS PASSING BY IN THE WEST TO NORTHWEST FLOW ALOFT. CLOUD COVER WAS INCREASED OVERNIGHT INTO SUNDAY AS THE CIRRUS HAS BEEN RATHER THICK AND MODELS INDICATE IT MAY GET THICKER. SOME MID CLOUDS WILL ALSO PASS BY FROM TIME TO TIME ON SUNDAY AS THE SHORTWAVE EJECTS INTO THE SOUTHEASTERN STATES. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM EDT SAT MAR 21 2015 18Z SFC ANALYSIS SHOWS HIGH PRESSURE NOSING DEEPER INTO EAST KENTUCKY KEEPING THE SKIES MOSTLY CLEAR...ASIDE FROM A SOME HIGH CLOUDS SEEPING NORTH FROM LOW PRESSURE WELL TO THE SOUTHWEST OF THE AREA. DESPITE THE HIGH PRESSURE AND RETURNING SUNSHINE... DEWPOINTS REMAIN IN THE UPPER 30S AND LOWER 40S KEEPING THE RH AROUND 50 PERCENT FOR MUCH OF THE AREA. MEANWHILE...TEMPERATURES ARE STILL CATCHING UP TO FORECAST HIGHS WITH A COUPLE OF HOURS OF CLIMBING YET TO GO...RANGING FROM LOW 60S IN THE SOUTH TO THE MID 50S IN THE NORTH. WINDS ARE GENERALLY LIGHT FROM THE SOUTHWEST... THOUGH ON THE NORTHEAST FRINGE OF THE HIGH PRESSURE SYSTEM THERE HAVE BEEN A FEW GUSTS TO BETWEEN 15 AND 20 KTS. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY DEPICT SOUTHERN STREAM ENERGY BRUSHING BY KENTUCKY SUNDAY INTO MONDAY AS A BROAD TROUGH SLOWLY MOVES THROUGH THE LOWER MISSISSIPPI VALLEY AND DEEP SOUTH. DURING THIS TIME...EASTERN KENTUCKY WILL BE IN THE MIDST OF GENERALLY BENIGN NORTHWEST FLOW IN WHICH ANY NORTHERN STREAM ENERGY STAYS OFF TO THE NORTHEAST OF THE AREA. HEIGHTS DO FALL A BIT TONIGHT INTO SUNDAY...BUT NOT DRAMATICALLY ENOUGH TO HAVE MUCH IMPACT ON SENSIBLE WEATHER. GIVEN THE MODEL AGREEMENT...HAVE FAVORED THE HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS THROUGH MONDAY MORNING. SENSIBLE WEATHER WILL FEATURE A COOL NIGHT DESPITE THE HIGH CLOUDS DRIFTING IN FROM THE SOUTHWEST FROM A WEAK LOW NEAR THE CENTRAL GULF COAST. AT THE SAME TIME...A COLD FRONT WILL SLIP INTO AND THROUGH THE AREA WITH NOT MUCH IN THE WAY OF MOISTURE. EXPECTING A DECENT START TO THE NIGHT FOR DECOUPLING AND RADIATIONAL COOLING SO HAVE BROUGHT THE VALLEY TEMPS DOWN QUICKER THAN THE MODELS WOULD SUGGEST. THE COLDER SPOTS MIX OUT IN THE MORNING UNDER PARTIAL SUNSHINE SUNDAY WITH TEMPERATURES TOPPING OUT A CATEGORY OR TWO BELOW TODAY/S HIGHS. WITH THE FRONT SOUTH OF THE AREA FOR SUNDAY NIGHT WE WILL SEE SOME COLDER TEMPERATURES ACROSS THE BOARD WITH SOME MINOR RIDGE TO VALLEY DIFFERENCES BY DAWN. FOR TONIGHT...PATCHY FOG CAN BE EXPECTED IN THE VALLEYS TOWARD DAWN WHILE ON SUNDAY NIGHT THERE MAY BE SOME PATCHES OF FROST IN THE VALLEYS. HAVE LEFT THE FROST OUT OF THE ZFP FORECAST FOR NOW...BUT DID ADD SOME TO THE GRIDS. AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO SUNDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD. AS FOR POPS...KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 235 PM EDT SAT MAR 21 2015 THE UPCOMING WEEK WILL FEATURE A TRANSITION FROM MEAN ZONAL FLOW EARLY IN THE PERIOD TO A HIGHLY AMPLIFIED PATTERN BY THE END OF THE PERIOD...WITH A DEEP TROUGH BECOMING ESTABLISHED IN THE EASTERN UNITED STATES WITH A RIDGE IN THE WEST. THIS WILL RESULT IN A SIGNIFICANT COOL DOWN AS WE HEAD INTO NEXT WEEKEND. THE START OF THE FORECAST PERIOD WILL FEATURE A SHORT WAVE MOVING THROUGH THE SOUTHERN STREAM ACROSS THE SOUTHEAST U.S. AND THEN OFF THE ATLANTIC COAST. A WEAK SYSTEM WILL ALSO BE PASSING BY TO OUR NORTH. OTHER THAN INCREASED CLOUDINESS THERE SHOULD BE LITTLE IMPACT TO OUR AREA FROM THESE SYSTEMS. AS WE MOVE INTO MID WEEK A MUCH MORE SIGNIFICANT SHORT WAVE WILL EMERGE INTO THE PLAINS. OUT AHEAD OF THIS...A SURFACE WARM FRONT WILL MOVE ACROSS THE REGION WITH A SIGNIFICANT SURGE OF WARM AIR MOVING INTO THE AREA AHEAD OF AN ADVANCING COLD FRONT. AS THE UPPER SYSTEM AND SURFACE LOW MOVE INTO THE GREAT LAKES REGION THE COLD FRONT WILL MOVE INTO ERN KY WEDNESDAY NIGHT INTO THURSDAY. THIS WILL BRING A GOOD CHANCE OF RAIN...WITH COOLER TEMPERATURES FOLLOWING. HAVE DECIDED TO ADD A SLIGHT CHANCE OF THUNDER WITH THIS FRONTAL PASSAGE AS WELL..WHICH WILL BE IN GOOD AGREEMENT WITH WFOS TO OUR WEST AND SOUTH. A SECOND SURGE OF COLDER AIR LOOKS TO IMMEDIATELY FOLLOW THE INITIAL COLD FRONTAL PASSAGE...AND THE POSSIBILITY EXISTS FOR SOME SNOW TO AT LEAST MIX IN WITH RAIN IF ANY PRECIPITATION LINGERS INTO FRIDAY NIGHT. THE OPERATIONAL GFS IS THE MOST AGGRESSIVE MODEL WITH THE COLD AIR SURGE...WITH THE ECMWF AND GFS ENSEMBLE MEAN...WHILE STILL COLD...NOT AS IMPRESSIVE...WITH 85H TEMPERATURES 5 DEGREES OR SO WARMER. AT THIS POINT THERE IS STILL CONSIDERABLE UNCERTAINTY REGARDING THE WEATHER DETAILS FOR THE END OF THE WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 135 AM EDT SUN MAR 22 2015 DRY COLD FRONT CONTINUES TO DROP SOUTH ACROSS EASTERN KENTUCKY TONIGHT. WINDS HAVE SHIFTED ACROSS NORTHERN PORTIONS OF THE CWA GENERALLY ALONG AND NORTH OF THE MOUNTAIN PARKWAY THIS HOUR TO GENERALLY LIGHT NORTH AND NORTHEAST WINDS. SOUTHERN SITES SUCH AS SME COULD SEE SOME LIGHT MVFR FOG TONIGHT...HOWEVER CONFIDENCE IS LOW AT THIS POINT DEPENDING ON HOW MUCH MIXING IF ANY OCCURS WITH DRY COLD FRONT. THE GUIDANCE DID LEAN TOWARD JUST ABOVE OR RIGHT AT MVFR...SO DID OPT TO LEAVE A WEAK MVFR SIGNAL IN THE SME TAF STARTING AT 9Z. OTHERWISE VFR WILL BE THE STORY THROUGH THE TAF PERIOD WITH GENERALLY HIGH TO POSSIBLY MID LEVEL CLOUDS. WINDS THROUGH MUCH OF THE TAF PERIOD WILL REMAIN LIGHT OUT OF THE NORTH TO NORTHEAST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...DJ SHORT TERM...GREIF LONG TERM...SBH AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
135 AM EDT SUN MAR 22 2015 .UPDATE... ISSUED AT 1100 PM EDT SAT MAR 21 2015 HOURLY GRIDS HAVE BEEN UPDATED TO ACCOUNT FOR THE LATEST OBSERVATIONS AND THE DRY COLD FRONT CROSSING THE AREA. THIS FRONTAL PASSAGE SHOULD LEAD TO ENOUGH MIXING OF THE DECOUPLED VALLEYS IN THE SOUTHEAST FOR AT LEAST A COUPLE OF HOURS AS IT MOVES THROUGH...BEFORE TEMPS AGAIN DROP OFF LATE TONIGHT BEHIND THE FRONT. THE HOURLY TEMPERATURES HAVE BEEN BLENDED TO THE PREVIOUS CURVED AFTER 3 AM TO ACCOUNT FOR THIS EXPECTATION. UPDATE ISSUED AT 810 PM EDT SAT MAR 21 2015 HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS AND SATELLITE IMAGERY. THE COLD FRONT THAT IS LACKING IN LOW LEVEL MOISTURE IS DROPPING INTO THE NORTHERN PART OF THE CWA ATTM. THIS FRONT WILL DROP SOUTH ACROSS THE REMAINDER OF THE CWA DURING THE REST OF THIS EVENING AND INTO THE OVERNIGHT HOURS. THIS FRONT WILL BRING LITTLE MORE THAN A SHIFT IN WINDS FROM THE WEST OR SOUTHWEST TO THE NORTH AND NORTHEAST ON RIDGETOPS AND IN EXPOSED LOCATIONS. CIRRUS ASSOCIATED WITH A SHORTWAVE WORKING FROM THE SOUTHERN PLAINS TOWARD THE MS VALLEY REGION CONTINUES TO MOVE OVERHEAD AS IT WORKS AROUND RIDGING EXTENDING FROM THE GULF OF MEXICO INTO THE SOUTHEAST. THERE IS ADDITIONAL CIRRUS PASSING BY IN THE WEST TO NORTHWEST FLOW ALOFT. CLOUD COVER WAS INCREASED OVERNIGHT INTO SUNDAY AS THE CIRRUS HAS BEEN RATHER THICK AND MODELS INDICATE IT MAY GET THICKER. SOME MID CLOUDS WILL ALSO PASS BY FROM TIME TO TIME ON SUNDAY AS THE SHORTWAVE EJECTS INTO THE SOUTHEASTERN STATES. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 320 PM EDT SAT MAR 21 2015 18Z SFC ANALYSIS SHOWS HIGH PRESSURE NOSING DEEPER INTO EAST KENTUCKY KEEPING THE SKIES MOSTLY CLEAR...ASIDE FROM A SOME HIGH CLOUDS SEEPING NORTH FROM LOW PRESSURE WELL TO THE SOUTHWEST OF THE AREA. DESPITE THE HIGH PRESSURE AND RETURNING SUNSHINE... DEWPOINTS REMAIN IN THE UPPER 30S AND LOWER 40S KEEPING THE RH AROUND 50 PERCENT FOR MUCH OF THE AREA. MEANWHILE...TEMPERATURES ARE STILL CATCHING UP TO FORECAST HIGHS WITH A COUPLE OF HOURS OF CLIMBING YET TO GO...RANGING FROM LOW 60S IN THE SOUTH TO THE MID 50S IN THE NORTH. WINDS ARE GENERALLY LIGHT FROM THE SOUTHWEST... THOUGH ON THE NORTHEAST FRINGE OF THE HIGH PRESSURE SYSTEM THERE HAVE BEEN A FEW GUSTS TO BETWEEN 15 AND 20 KTS. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY DEPICT SOUTHERN STREAM ENERGY BRUSHING BY KENTUCKY SUNDAY INTO MONDAY AS A BROAD TROUGH SLOWLY MOVES THROUGH THE LOWER MISSISSIPPI VALLEY AND DEEP SOUTH. DURING THIS TIME...EASTERN KENTUCKY WILL BE IN THE MIDST OF GENERALLY BENIGN NORTHWEST FLOW IN WHICH ANY NORTHERN STREAM ENERGY STAYS OFF TO THE NORTHEAST OF THE AREA. HEIGHTS DO FALL A BIT TONIGHT INTO SUNDAY...BUT NOT DRAMATICALLY ENOUGH TO HAVE MUCH IMPACT ON SENSIBLE WEATHER. GIVEN THE MODEL AGREEMENT...HAVE FAVORED THE HIGHER RESOLUTION HRRR AND NAM12 FOR DETAILS THROUGH MONDAY MORNING. SENSIBLE WEATHER WILL FEATURE A COOL NIGHT DESPITE THE HIGH CLOUDS DRIFTING IN FROM THE SOUTHWEST FROM A WEAK LOW NEAR THE CENTRAL GULF COAST. AT THE SAME TIME...A COLD FRONT WILL SLIP INTO AND THROUGH THE AREA WITH NOT MUCH IN THE WAY OF MOISTURE. EXPECTING A DECENT START TO THE NIGHT FOR DECOUPLING AND RADIATIONAL COOLING SO HAVE BROUGHT THE VALLEY TEMPS DOWN QUICKER THAN THE MODELS WOULD SUGGEST. THE COLDER SPOTS MIX OUT IN THE MORNING UNDER PARTIAL SUNSHINE SUNDAY WITH TEMPERATURES TOPPING OUT A CATEGORY OR TWO BELOW TODAY/S HIGHS. WITH THE FRONT SOUTH OF THE AREA FOR SUNDAY NIGHT WE WILL SEE SOME COLDER TEMPERATURES ACROSS THE BOARD WITH SOME MINOR RIDGE TO VALLEY DIFFERENCES BY DAWN. FOR TONIGHT...PATCHY FOG CAN BE EXPECTED IN THE VALLEYS TOWARD DAWN WHILE ON SUNDAY NIGHT THERE MAY BE SOME PATCHES OF FROST IN THE VALLEYS. HAVE LEFT THE FROST OUT OF THE ZFP FORECAST FOR NOW...BUT DID ADD SOME TO THE GRIDS. AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO SUNDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD. AS FOR POPS...KEPT THEM LOW...IN LINE WITH ALL MOS GUIDANCE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 235 PM EDT SAT MAR 21 2015 THE UPCOMING WEEK WILL FEATURE A TRANSITION FROM MEAN ZONAL FLOW EARLY IN THE PERIOD TO A HIGHLY AMPLIFIED PATTERN BY THE END OF THE PERIOD...WITH A DEEP TROUGH BECOMING ESTABLISHED IN THE EASTERN UNITED STATES WITH A RIDGE IN THE WEST. THIS WILL RESULT IN A SIGNIFICANT COOL DOWN AS WE HEAD INTO NEXT WEEKEND. THE START OF THE FORECAST PERIOD WILL FEATURE A SHORT WAVE MOVING THROUGH THE SOUTHERN STREAM ACROSS THE SOUTHEAST U.S. AND THEN OFF THE ATLANTIC COAST. A WEAK SYSTEM WILL ALSO BE PASSING BY TO OUR NORTH. OTHER THAN INCREASED CLOUDINESS THERE SHOULD BE LITTLE IMPACT TO OUR AREA FROM THESE SYSTEMS. AS WE MOVE INTO MID WEEK A MUCH MORE SIGNIFICANT SHORT WAVE WILL EMERGE INTO THE PLAINS. OUT AHEAD OF THIS...A SURFACE WARM FRONT WILL MOVE ACROSS THE REGION WITH A SIGNIFICANT SURGE OF WARM AIR MOVING INTO THE AREA AHEAD OF AN ADVANCING COLD FRONT. AS THE UPPER SYSTEM AND SURFACE LOW MOVE INTO THE GREAT LAKES REGION THE COLD FRONT WILL MOVE INTO ERN KY WEDNESDAY NIGHT INTO THURSDAY. THIS WILL BRING A GOOD CHANCE OF RAIN...WITH COOLER TEMPERATURES FOLLOWING. HAVE DECIDED TO ADD A SLIGHT CHANCE OF THUNDER WITH THIS FRONTAL PASSAGE AS WELL..WHICH WILL BE IN GOOD AGREEMENT WITH WFOS TO OUR WEST AND SOUTH. A SECOND SURGE OF COLDER AIR LOOKS TO IMMEDIATELY FOLLOW THE INITIAL COLD FRONTAL PASSAGE...AND THE POSSIBILITY EXISTS FOR SOME SNOW TO AT LEAST MIX IN WITH RAIN IF ANY PRECIPITATION LINGERS INTO FRIDAY NIGHT. THE OPERATIONAL GFS IS THE MOST AGGRESSIVE MODEL WITH THE COLD AIR SURGE...WITH THE ECMWF AND GFS ENSEMBLE MEAN...WHILE STILL COLD...NOT AS IMPRESSIVE...WITH 85H TEMPERATURES 5 DEGREES OR SO WARMER. AT THIS POINT THERE IS STILL CONSIDERABLE UNCERTAINTY REGARDING THE WEATHER DETAILS FOR THE END OF THE WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 135 AM EDT SUN MAR 22 2015 DRY COLD FRONT CONTINUES TO DROP SOUTH ACROSS EASTERN KENTUCKY TONIGHT. WINDS HAVE SHIFTED ACROSS NORTHERN PORTIONS OF THE CWA GENERALLY ALONG AND NORTH OF THE MOUNTAIN PARKWAY THIS HOUR TO GENERALLY LIGHT NORTH AND NORTHEAST WINDS. SOUTHERN SITES SUCH AS SME COULD SEE SOME LIGHT MVFR FOG TONIGHT...HOWEVER CONFIDENCE IS LOW AT THIS POINT DEPENDING ON HOW MUCH MIXING IF ANY OCCURS WITH DRY COLD FRONT. THE GUIDANCE DID LEAN TOWARD JUST ABOVE OR RIGHT AT MVFR...SO DID OPT TO LEAVE A WEAK MVFR SIGNAL IN THE SME TAF STARTING AT 9Z. OTHERWISE VFR WILL BE THE STORY THROUGH THE TAF PERIOD WITH GENERALLY HIGH TO POSSIBLY MID LEVEL CLOUDS. WINDS THROUGH MUCH OF THE TAF PERIOD WILL REMAIN LIGHT OUT OF THE NORTH TO NORTHEAST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...SBH AVIATION...DJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
502 AM EDT SUN MAR 22 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 502 AM EDT SUN MAR 22 2015 DESPITE 850MB TEMPS AROUND -17C PER LATEST RAP ANALYSIS...THERE ARE NO LAKE EFFECT CLOUDS DEVELOPING OFF THE OPEN WATER OF NCNTRL LAKE SUPERIOR. EVEN OFF THE OPEN WATER EXTENDING FROM THE KEWEENAW TO MUNISING...THERE WAS A LITTLE BURST OF LES EARLIER IN THE NIGHT INTO ALGER COUNTY...BUT THAT HAS SINCE DISSIPATED. CONVERGENCE HAS RECENTLY STRENGTHENED OVER THAT OPEN WATER AREA AS A WIND SHIFT TO THE ENE IS PROGRESSING TOWARD THE MARQUETTE COUNTY SHORELINE WHERE LAND BREEZE IS EVIDENT. IN JUST IN THE LAST HR...THIS HAS RESULTED IN NEW LIGHT LES DEVELOPMENT OVER FAR ERN MARQUETTE COUNTY. OTHERWISE...AS OF 09Z...THAT IS IT FOR LES AND EVEN LAKE EFFECT CLOUDS OFF LAKE SUPERIOR. UPSTREAM 00Z SOUNDINGS AT KINL/CYPL TELL THE STORY AS NOT ONLY WAS THE AIR MASS DRY IN THE LOW TO MID LEVELS...BUT BOTH SOUNDINGS ALSO EXHIBITED THE HOSTILE FOR LES INVERTED V LOOK. WOULD EXPECT A CONTINUED UPTICK IN LES OFF SCNTRL LAKE SUPERIOR INTO FAR ERN MARQUETTE COUNTY AND ALGER COUNTY EARLY THIS MORNING AS WE APPROACH THE COOLEST PART OF THE DIURNAL CYCLE/MOST FAVORABLE TIME OF DAY FOR LES AT THIS TIME OF YEAR. THAT SAID...IT WON`T BE MORE THAN LIGHT SNOW SHOWERS AND FLURRIES WITH ANY ACCUMULATION UNDER 1 INCH. THE DISRUPTIVE EFFECT OF DAYTIME HEATING AT THIS TIME OF YEAR COMBINED WITH 850MB THERMAL TROF SHIFTING E WILL BRING AN END TO THE LIGHT LES EARLY THIS AFTN. ACROSS THE REST OF THE FCST AREA...EXPECT A PARTLY TO MOSTLY SUNNY DAY WITH HIGHS IN THE 20S ACROSS MOST OF THE N AND E TO THE 30S TOWARD THE MI/WI BORDER. SHORTWAVE MOVING ACROSS THE DAKOTAS TODAY AND INTO THE WRN GREAT LAKES TONIGHT WILL WEAKEN AS IT ENCOUNTERS INCREASINGLY CONFLUENT FLOW. MODELS SHOW THIS WAVE SPREADING PCPN ACROSS MN INTO WI. MODELS WHICH HAD PREVIOUSLY BROUGHT THE PCPN TO NEAR THE MI/WI BORDER TONIGHT HAVE TRENDED S WITH THE NRN EDGE OF THE PCPN. GIVEN THE CONFLUENT FLOW OVER THE UPPER LAKES...ESTABLISHED ARCTIC AIR AND CONTINUED DRY AIR EMANATING FROM THE SFC HIGH PRES AREA WHICH WILL BE SLOWLY DRIFTING E OF HERE...A DRY FCST IS THE WAY TO GO TONIGHT. MIN TEMPS TONIGHT COULD BE QUITE LOW...ESPECIALLY OVER THE ERN FCST AREA WHERE HIGH/MID CLOUDS WILL BE THINNEST AND WHERE THERE WILL BE LIGHT ENE WINDS OFF ONTARIO. EXPECT TRADITIONAL COLD SPOTS TO FALL TO NEAR 0F OR EVEN BLO. DEPENDING ON THICKNESS OF CLOUDS...SINGLE DIGITS ABOVE ZERO MAY BE COMMON IN THE INTERIOR WESTWARD INTO CNTRL UPPER MI. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 451 AM EDT SUN MAR 22 2015 AT 12Z MONDAY UPPER MI WILL STILL BE IN BETWEEN SYSTEMS. THE NEXT SHORTWAVE WILL BE OVER S MANITOBA. HIGH PRESSURE WILL STILL BE THE MAIN FEATURE...CENTERED OVER THE E HALF OF ONTARIO/E LAKE SUPERIOR/E UPPER MI. NOT EXPECTING MUCH OUT OF THE SHORTWAVE TO THE NW AS IT WORKS THROUGH A REGION OF PRETTY DRY AIR. THE PRECIP OVER NW MN MONDAY AFTERNOON IS EXPECTED TO ALL BUT DRY UP AS IT CROSSES MN AND W LAKE SUPERIOR. DID KEEP JUST A SMALL POCKET OF SLIGHT CHANCE POPS OVER W LAKE SUPERIOR MONDAY NIGHT...AND N LAKE SUPERIOR LATE MONDAY NIGHT/TUESDAY MORNING. THE SFC HIGH WILL SLIDE TO THE SE OVER FAR SE ONTARIO/S QUEBEC BY TUESDAY MORNING. LOOK FOR THE RETURN OF S WINDS ON TUESDAY...WITH 850MB TEMPS RISING TO C TO -2C BY THE END OF THE DAY. DOWNSLOPE AREAS AND LOCATIONS ALONG THE WI BORDER MAY SEE TEMPS IN THE UPPER 40S TO NEAR 50F...ESPECIALLY IF THE ANTICIPATED MOSTLY SUNNY SKY PANS OUT. SLOWED DOWN/BROUGHT MORE TEMPORAL DEFINITION TO THE INCOMING SNOW AND MIXED PRECIP LATE TUESDAY NIGHT. THERE IS STILL ENOUGH UNCERTAINTY IN THE FCST SOLUTIONS TO KEEP THE MENTION OF SEVERAL INCHES OF SNOW POSSIBLE IN THE HWO FOR LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING. EXPECT SFC LOWS FROM THE DAKOTAS AND E KS TUESDAY AFTERNOON TO MERGE ACROSS WI BY DAYBREAK WEDNESDAY. 850MB WINDS OUT OF THE S AT 40- 50KTS WILL BE OUT AHEAD OF THE LOW /ACROSS LAKE MI AT 12Z WEDNESDAY/...USHERING IN WARMER AIR. LOOKS LIKE A GOOD CHANCE OF MIXED PRECIP STILL OVER S CENTRAL AND E UPPER MI WEDNESDAY AFTERNOON...WHICH WILL MINIMIZE THE POTENTIAL FOR QUICKLY ACCUMULATING SNOW. DEF/LIKELY SNOW WILL EXIT WEDNESDAY AFTERNOON AS THE CONSOLIDATED LOW EXITS FROM E UPPER MI TO E ONTARIO. OTHERWISE...PRECIP SHOULD STAY MAINLY IN THE FORM OF SNOW NW OF A LINE FROM IRON TO MUNISING. MODERATE SNOW WILL BE POSSIBLE OVER THE FAR W...DIMINISHING TO A GOOD CHANCE AS STEADY N TO NW WINDS TAKE HOLD AND COLDER AIR PUSHES IN ON THURSDAY. 850MB TEMPS WILL FALL TO - 18 TO -22C THURSDAY AFTERNOON INTO EARLY FRIDAY MORNING. LIGHTER AND LESS FAVORABLE W TO SW WINDS SHOULD PUSH IN LATER FRIDAY...AS ANOTHER AREA OF HIGH PRESSURE SINKS IN FROM S CENTRAL CANADA. LOOKING FARTHER OUT...MODELS ARE HINTING AT ANOTHER SYSTEM FOR THE END OF THE WEEKEND. STAY TUNED. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 133 AM EDT SUN MAR 22 2015 A WEAK SURGE OF MOISTURE MOVING IN OVERNIGHT SHOULD RESULT IN INCREASING LAKE EFFECT CLOUD COVERAGE AS WINDS VEER TO THE NORTH- NORTHWEST. KSAW HAS THE BEST OPPORTUNITY FOR HIGH END MVFR CEILINGS. WITH A MORE ANTICYCLONIC FLOW OVER THE WEST...CONFIDENCE IS TOO LOW TO INCLUDE ANY MVFR MENTION AT KIWD/KCMX. THE MOISTURE WILL DEPART THIS MORNING AND WINDS WILL BACK...LEADING TO DIMINISHING CLOUDS/LES AS HIGH PRES RIDGE CONTINUES TO MOVE OVER THE REGION. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 502 AM EDT SUN MAR 22 2015 JUST AHEAD OF A HIGH PRES RIDGE EXTENDING SE OVER WRN LAKE SUPERIOR...NW WINDS OVER FAR ERN LAKE SUPERIOR WILL PROBABLY INCREASE TO 15-25KT TODAY. OTHERWISE...WINDS WILL BE UNDER 20KT. WINDS WILL THEN BE UNDER 20KT ACROSS THE LAKE TONIGHT AS THE HIGH PRES RIDGE DRIFTS E. WINDS SHOULD GENERALLY REMAIN UNDER 20KT MON INTO EARLY TUE AS PRES GRADIENT REMAINS WEAK. ATTENTION THEN TURNS TO DEEPENING LOW PRES WHICH WILL TRACK FROM THE CNTRL PLAINS TUE TO EASTERN UPPER MI WED AFTN. AHEAD OF THIS SYSTEM...SE TO E WINDS WILL INCREASE TUE NIGHT TO 15-25KT ACROSS MUCH OF LAKE SUPERIOR. WINDS WILL THEN VEER AROUND TO THE N WED/THU. WHILE 15-25KT WINDS WILL PROBABLY BE COMMON...WILL NEED TO WATCH FOR STRONGER WINDS UP TO 30KT AND POTENTIALLY UP TO GALE FORCE AT SOME POINT WED INTO EARLY THU FOR PARTS OF LAKE SUPERIOR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...JLB MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1120 PM MDT SAT MAR 21 2015 .AVIATION... 06Z TAF CYCLE CLEARING SKIES AND LIGHT WINDS MAY FAVOR SHALLOW FOG IN NORTHERN AND WESTERN VALLEYS BY SUNRISE. THE AREA AROUND KROW MAY ALSO FAVOR SOME FOG HOWEVER CONFIDENCE TOO LOW TO INCLUDE WITHIN THE PREVAILING FORECAST. OTHERWISE...VFR ALL AREAS THROUGH SUNDAY WITH A FEW LATE AFTERNOON BREEZES ALONG THE AZ BORDER AND EASTERN SLOPES. GUYER && .PREV DISCUSSION...541 PM MDT SAT MAR 21 2015... .UPDATE... INTERESTINGLY...THOUGH IT IS QUITE DIFFICULT TO GET SE BOUND CONVECTION TO MAKE IT INTO THE ABQ METRO EVEN IN THE SUMMER...HERE IT IS SURVIVING INTO THE NORTH PORTION OF THE METRO. IT SHOULD NOT LAST MORE THAN ANOTHER HALF HOUR TO HOUR AND AMOUNTS WILL BE UNDER A TENTH OF AN INCH...BUT FELT IT WAS ENOUGH TO NECESSITATE A QUICK UPDATE. SO...IT IS THUS. ALSO TWEAKED POPS AND SKY COVER SLIGHTLY IN A FEW OTHER SPOTS. 43 && .PREV DISCUSSION...310 PM MDT SAT MAR 21 2015... .SYNOPSIS... DRYING AND WARMING TREND SUNDAY AND MONDAY WITH SOME AFTERNOON WINDINESS MONDAY. CRITICAL FIRE WEATHER CONDITIONS COULD DEVELOP MONDAY AFTERNOON FROM THE EAST SLOPES OF THE CENTRAL MOUNTAIN CHAIN OVER THE NORTHEAST AND EAST CENTRAL PLAINS. SOMEWHAT COOLER TUESDAY...ALTHOUGH HIGH TEMPERATURES WILL REMAIN ABOVE AVERAGE. THERE IS POTENTIAL FOR A BRIEF PERIOD OF WETTER WEATHER AROUND THE MIDDLE OF NEXT WEEK...BUT FORECAST MODELS DIFFER CONSIDERABLY. A DRYING TREND LOOKS TO RETURN FOR NEXT FRIDAY AND SATURDAY. && .DISCUSSION... PUNY CONVECTION OVER SOME OF THE NORTHERN...WESTERN AND CENTRAL HIGH TERRAIN THIS AFTERNOON. KEPT THE SMALL INHERITED POPS FOR THIS EVENING WITH LITTLE CHANGE...ALTHOUGH BOTH HRRR AND NAM12 MAKE A CASE FOR ISOLATED CELLS THIS EVENING OVER THE FAR NORTHEAST. GIVEN THERE/S NOT MUCH GOING ON OVER THE MTS ON THE COLORADO SIDE OF THE BORDER AT THE MOMENT...THERE/S PROBABLY NOT MUCH CHANCE FOR ONE TO SCORE A DIRECT HIT ON ANY RAINFALL MEASURING BUCKET. OTHERWISE...THERE IS POTENTIAL FOR AT LEAST PATCHY FOG IN THE PECOS VALLEY SOUTH OF INTERSTATE 40 EASTWARD TO THE TEXAS BORDER LATER TONIGHT AND EARLY SUNDAY...INCLUDING THE CLOVIS/PORTALES AREA...WHERE 40S DEWPOINTS FORECAST TO REMAIN IN PLACE AND THE MID TO HIGH LEVEL MOISTURE CLEARS OUT WITH THE DEPARTING LOW/TROUGH. DEW POINTS DRY OUT SUNDAY AS AN WEAK RIDGE BUILDS OVER THE STATE. A SFC LEE TROUGH WILL BE ESTABLISHED...AND TEMPERATURES WILL RANGE FROM AROUND 5 TO NEARLY 20 DEGREES ABOVE AVERAGE...WITH THE GREATEST DEVIATION FROM NORMAL ACROSS NORTH CENTRAL AND NORTHEAST. A TREND TOWARD ZONAL FLOW MONDAY...AND COMBINED WITH THE SFC TROUGH...BREEZY TO WINDY CONDITIONS LOOK TO DEVELOP ESPECIALLY FROM THE CENTRAL MT CHAIN OVER THE NORTHEAST AND EAST CENTRAL PLAINS. WIDESPREAD WIND ADVY CRITERIA DOESN/T APPEAR TO BE LIKELY...HOWEVER...IMPACTS WILL BE FIRE WEATHER RELATED AS HIGHS WILL SOAR IN TO THE UPPER 70S AND 80S MONDAY AFTERNOON OVER THAT PART OF THE FORECAST AREA. HIGH TEMPERATURE DEVIATIONS FROM AVERAGE WILL BE SOMEWHAT SIMILAR TO THOSE OF SUNDAY. TUESDAY WILL BE SLIGHTLY COOLER AS THE SFC TROUGH AND ASSOCIATED SHORT WAVE TRACK NORTHEAST OF NEW MEXICO...LEAVING SOME GUSTY NORTHWEST WINDS TO AFFECT THE CENTRAL MT CHAIN AND ADJACENT HIGHLANDS. FOR THE MID TO LATE WEEK PERIOD...THE ECMWF REMAINS THE WETTER MODEL...COMPARED TO THE GFS...WHICH DEVELOPS 2 SEPARATE FEATURES...A CUTOFF LOW OVER SOCAL...AND A SHORT WAVE IN THE NW FLOW ALOFT WHICH CLIPS NORTHEAST NM. GIVEN THE DIFFERENCES...REINED IN POPULATED POPS FOR WED NIGHT/THURS. FRIDAY AND SATURDAY LOOK DRY...BUT ECMWF DROPS ANOTHER SHORT WAVE INTO NORTHERN NEW MEXICO SUNDAY...WHILE THE GFS BOOTS OUT THE SOCAL LOW FARTHER NORTH AND OVER THE STATE. EITHER WAY...IT LOOKS LIKE SPOTTY PRECIPITATION COULD DEVELOP. && .FIRE WEATHER... ...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE ON MONDAY ACROSS MUCH OF EASTERN NEW MEXICO... LOW PRESSURE SYSTEM ALOFT CONTINUES TO SWING SOUTH OF NM TODAY WITH SOME STEADY BATCHES OF LIGHT PRECIPITATION FAVORING THE SOUTHERN TIER OF THE STATE...MOSTLY OUT OF THE ABQ FIRE WEATHER FORECAST AREA. HOWEVER...SOME REMNANT INSTABILITY AND MOISTURE IS LEADING TO DEVELOPMENT OF NEW SHOWERS AND STORMS OVER THE HIGHER TERRAIN OF CENTRAL NM THIS AFTERNOON. THIS ACTIVITY SHOULD REMAIN FAIRLY ISOLATED WITH LOW PROBABILITIES FOR ACTUAL WETTING RAINFALL...BUT A FEW CLOUD TO GROUND LIGHTNING STRIKES COULD OCCUR. DRIER AIR IN THE MID TO UPPER LEVELS OF THE ATMOSPHERE IS SLOWLY FILTERING INTO THE STATE FROM THE NORTH NORTHWEST...AND THIS TREND WILL PERSIST OVERNIGHT. HOWEVER...THE DEWPOINTS NEAR THE SURFACE WILL BE SLOWER TO RESPOND TO THIS DRYING...THUS ANOTHER NIGHT/MORNING OF EXCELLENT RH RECOVERY IS ANTICIPATED THROUGH EARLY SUNDAY. THE REMNANTS OF THE LOW PRESSURE SYSTEM WILL HAVE FULLY EXITED EAST OF NM ON SUNDAY...GIVING WAY TO A RIDGE OF HIGH PRESSURE. THIS WILL KEEP THE DRYING TREND GOING...WITH LOW LAYER RH/DEWPOINTS ALSO QUICKLY RESPONDING DOWNWARD AS DEEP MIXING ENSUES IN AN ABOVE NORMAL TEMPERATURE REGIME. PRECIPITATION WILL HAVE FULLY ESCAPED AND THE ENTIRE FORECAST AREA SHOULD EXCEED SEASONAL AVERAGES. A WEAK LEE SIDE SURFACE TROUGH WILL STRUGGLE TO TAKE SHAPE...BUT WILL NOT FULLY COME TOGETHER BEFORE DUSK SUNDAY. THE PATTERN TURNS MORE CRITICAL ON MONDAY AS THE RIDGE ALOFT BREAKS DOWN AND STRONGER WESTERLY FLOW ALOFT DEVELOPS OVER NM WITH AVERAGE SPEEDS OF 30-40 MPH IN THE 10000 TO 18000 FT LAYER. THIS WILL BE A NOTABLE STRENGTHENING OF THESE UPPER LEVEL WINDS THAT HAS YET TO TRANSFER TO THE SURFACE THUS FAR THIS YEAR. AS THE LEE SIDE SURFACE CYCLONE BECOMES BETTER ESTABLISHED EXCELLENT MIXING IS FORECAST...AND BREEZY TO WINDY CONDITIONS WILL ENSUE MONDAY AFTERNOON WHILE THE WARMER THAN AVERAGE AND DRY CONDITIONS PERSIST. WIND SPEEDS LOOK TO EXCEED CRITICAL SPEEDS OVER MUCH OF THE NORTHEASTERN QUADRANT OF NM WHERE RH WILL PLUMMET TO 10 TO 15 PERCENT MONDAY AFTERNOON...AND AFTER FURTHER COLLABORATION ON THE STATUS OF THE FINE OR 1-HOUR FUELS...BELIEVE THERE WILL BE ENOUGH FIRE DANGER JUXTAPOSED WITH THE CRITICAL WINDS/RH. THUS...A WATCH WILL BE HOISTED WITH THIS FORECAST PACKAGE. A SHORT WAVE TROUGH WILL PASS NORTH OF NM MONDAY NIGHT...KEEPING WINDS ALOFT STRONG...AND SOME MOUNTAIN WAVE ACTIVITY MAY EVEN CRASH EAST OF THE SANGRE DE CRISTOS INTO EARLY TUESDAY MORNING. THE REMAINDER OF TUESDAY SHOULD SEE A DECREASE IN SPEEDS ALOFT WITH SLIGHTLY COOLER...BUT STILL ABOVE AVERAGE TEMPERATURES PREVAILING. THE NEXT NOTABLE FEATURE WILL APPROACH ON THURSDAY AS A TROUGH DIVES SOUTHEAST OUT OF CANADA AND ADDITIONAL ENERGY SEPARATES AND CUTS OFF ON A TRAJECTORY NEAR OR WEST OF NM. FORECAST MODELS ARE HAVING DIFFICULTY RETAINING CONTINUITY BETWEEN RUNS AND AMONGST EACH OTHER. THE IMPACTS FROM THE COLDER AIR AND PRECIPITATION SEEM LESS CERTAIN ACCORDING TO THE GFS...WHILE THE EUROPEAN MODEL IS MORE ASSERTIVE WITH BOTH. 52 && .ABQ WATCHES/WARNINGS/ADVISORIES... FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING FOR THE FOLLOWING ZONES...NMZ103-104-107-108. && $$
AREA FORECAST DISCUSSION
NWS BUFFALO NY
421 AM EDT SUN MAR 22 2015 .SYNOPSIS... COLD AIR WILL CONTINUE TO POUR INTO THE REGION TODAY WITH SOME LAKE EFFECT SNOW SOUTH OF LAKE ONTARIO. HIGH PRESSURE WILL THEN BUILD ACROSS THE LOWER GREAT LAKES TONIGHT THROUGH TUESDAY. WHILE COLD WEATHER WILL ACCOMPANY THE AREA OF HIGH PRESSURE...SIGNIFICANT WARMING CAN BE EXPECTED BY MID WEEK. && .NEAR TERM /THROUGH TONIGHT/... AT 400 AM...SYRACUSE/BINGHAMTON RADAR LOOPS SHOW LAKE ENHANCED SNOW SHOWERS OF SOUTHEAST OF LAKE ONTARIO GENERALLY FOCUSED ON EASTERN WAYNE COUNTY. SURFACE OBS SHOW A CONVERGENCE BOUNDARY FOCUSED IN THE SAME LOCATION BETWEEN ROCHESTER AND FULTON. UNLIKE TYPICAL LAKE EFFECT EVENTS WHERE THESE BOUNDARIES ARE LAKE DRIVEN...THIS IS PRIMARILY A SYNOPTIC BOUNDARY ON THE SOUTHERN FRINGE OF AN UPPER LEVEL TROUGH. MOST HIGH RESOLUTION MODEL GUIDANCE CAPTURES THIS BOUNDARY WELL. CURIOUSLY MUCH OF THE 00Z HIGH RES GUIDANCE HAS SHIFTED QPF TO THE NORTHEAST OF THE BOUNDARY WHICH DOES NOT MATCH THE LATEST CONDITIONS. FORECAST WILL FOCUS ON THE BOUNDARY WHICH IS WELL DEPICTED BY THE HRRR AND SUPPORTED BY SURFACE WINDS OF MOST OTHER HIGH RES GUIDANCE. THERE IS LITTLE DOUBT THAT THE BOUNDARY WILL DROP SOUTHWARD MID-MORNING WHICH WILL PUSH STEADIER LAKE EFFECT SNOW ACROSS MONROE AND ONTARIO COUNTIES BY DAYBREAK. SNOW WILL BE SHORT-LIVED AS THE BOUNDARY CONTINUES ITS SOUTHWARD PUSH WITH SNOW LIKELY TO FALL APART AS THE BOUNDARY GETS FURTHER FROM THE MOISTURE OF LAKE ONTARIO. STEADIEST BANDS SHOULD BRING 3 TO 5 INCHES TO SOME LOCATIONS IN WAYNE COUNTY...WITH AMOUNTS DROPPING OFF DOWN TO ONLY AN INCH OR TWO IN THE ROCHESTER METRO AREA...AND EVEN LESS TO THE WEST. DAYTIME MIXING SHOULD FURTHER DISRUPT THE LAKE EFFECT BY EARLY AFTERNOON WHEN ACCUMULATING SNOW SHOULD BE DONE. THE AIRMASS IS PROBABLY DRY ENOUGH FOR SOME SUNSHINE UNTIL AFTERNOON CU DEVELOP SOUTH OF THE LAKE. TEMPERATURES WILL BE ON THE COOL SIDE...WITH HIGHS IN THE MID TO UPPER 20S IN MOST LOCATIONS...WITH SOME AREAS EAST OF LAKE ONTARIO STRUGGLING TO REACH 20. A WEAK SHORTWAVE WILL CLIP THE NORTH COUNTRY LATE THIS AFTERNOON AND EVENING WHICH MAY SPARK A FLURRY OR LIGHT SNOW SHOWERS. THIS ALSO MAY BRIEFLY ENHANCE LAKE EFFECT SNOW EAST AND SOUTHEAST OF LAKE ONTARIO...WITH VERY LIGHT ACCUMULATIONS POSSIBLE. ELSEWHERE...FAIR BUT CHILLY CONDITIONS WITH OVERNIGHT LOWS 5 TO 15 ABOVE. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... HIGH PRESSURE DROPPING SOUTHWARD FROM THE UPPER GREAT LAKES WILL PRESENT DRY WEATHER CONDITIONS ACROSS OUR REGION FOR MONDAY THROUGH TUESDAY. ACCOMPANYING THIS AREA OF HIGH PRESSURE WILL BE A DRY AIRMASS...ONE THAT WILL BRING LOW DEW POINTS IN THE SINGLE DIGITS. CLOUDS WILL THICKEN SOME OVER OUR EASTERN AREAS MONDAY NIGHT AS THE TAIL END OF AN UPPER LEVEL TROUGH CLIPS THE REGION. THIS AREA OF HIGH PRESSURE WILL SLIDE ACROSS THE REGION ON TUESDAY WITH ABUNDANT SUNSHINE. HIGHS ON MONDAY WILL REMAIN IN THE 20S...ABOUT 20 DEGREES BELOW NORMAL...WHILE ON TUESDAY UNDER SLIGHTLY WARMER TEMPERATURES ALOFT WE SHOULD CLIMB INTO THE 30S ACROSS THE REGION. TUESDAY NIGHT THIS AREA OF HIGH PRESSURE WILL SLIDE OFF THE EAST COAST...WITH A RETURN SOUTHERLY FLOW BRINGING BOTH A MILDER AND MOISTER AIRMASS. AS A WARM FRONT NEARS THE REGION FROM THE OHIO VALLEY A RAIN OR LOWER CHANCE...WET SNOW SHOWER IS POSSIBLE JUST BEFORE DAYBREAK WEDNESDAY MORNING. UNDER THIS SOUTHERLY FLOW OVERNIGHT LOWS TUESDAY NIGHT WILL RANGE FROM AROUND 20 EAST OF LAKE ONTARIO...TO UPPER 20S EAST OF LAKE ERIE. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... A STORM SYSTEM FROM THE UPPER GREAT LAKES WILL REACH OUR AREA TO START THE TIME PERIOD. THIS SYSTEM ACCOMPANIED BY A SHARP SHORTWAVE IS PROGGED TO LIFT NORTHEASTWARD FROM THE NORTHERN PLAINS TUESDAY TO ACROSS THE UPPER GREAT LAKES ON WEDNESDAY. A WARM FRONT WILL LIFT NORTHWARD ACROSS THE AREA ON WEDNESDAY...ALLOWING TEMPERATURES TO SURGE INTO THE LOW TO MID 50S FOR MOST OF THE AREA BY THE AFTERNOON. EXPECT TO SEE A SHIELD OF PRECIPITATION IN THE FORM OF RAIN LIFT NORTHWARD ACROSS THE AREA WEDNESDAY MORNING ALONG THE FRONT...BUT THEN WE COULD SEE THE PRECIPITATION WEAKEN/BECOME MORE SHOWERY BY WEDNESDAY AFTERNOON AS WE GET INTO THE WARM SECTOR AND THE SYNOPTIC FORCING MOVES INTO SOUTHERN ONTARIO. MODELS DIVERGE SLIGHTLY BY WEDNESDAY NIGHT INTO THURSDAY ON WHERE AN ELONGATED BAROCLINIC ZONE WILL SET UP. 12Z ECMWF PLACES THIS BOUNDARY SLIGHTLY FARTHER EAST THAN THE 12Z GFS SOLUTION. THE ECMWF SOLUTION WOULD MEAN MUCH LESS RAINFALL FOR WESTERN NY...BEING STUCK ON THE COLD SIDE OF THE BOUNDARY. THE GFS SOLUTION PRODUCES MUCH MORE RAINFALL FOR THE FORECAST AREA WITH A MORE FAVORABLE ORIENTATION OF THE BAROCLINIC ZONE JUST TO OUR WEST. THE POTENTIAL FOR WARMER WEATHER AND POTENTIALLY SIGNIFICANT RAINFALL STILLS BARES WATCHING FOR POSSIBLE HYDROLOGIC ISSUES STILL. BEHIND THIS WEATHER SYSTEM...THE WEEK WILL END WITH BELOW NORMAL TEMPERATURES AND THE POTENTIAL FOR SOME LAKE EFFECT SNOW SHOWERS SOUTHEAST OF LAKE ONTARIO AS A BROAD TROUGH CROSSES OVERHEAD. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... A DEVELOPING LAKE EFFECT BAND SE OF LAKE ONTARIO WILL DROP SOUTHWARD AND PROBABLY BRING A COUPLE HOURS OF STEADY SNOW TO THE ROCHESTER TERMINAL WITH IFR OR LOWER CONDITIONS. THIS MAY CLIP BUF/IAG/JHW WITH SOME LIGHT SNOW AND MVFR CLOUD DECKS AS A CONVERGENCE BOUNDARY CONTINUES TO DROP SOUTH THROUGH MID-MORNING. OTHERWISE...EXPECT VFR CONDITIONS. HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE LOWER LAKES THIS AFTERNOON WITH MOSTLY VFR CONDITIONS THROUGH TONIGHT. A WEAK UPPER LEVEL DISTURBANCE IS FORECAST TO CLIP THE NORTH COUNTRY...WHICH MAY LOWER CIGS AND BRING A BRIEF SNOW SHOWER TO ART/ROC TONIGHT. OUTLOOK... MONDAY AND TUESDAY...VFR. WEDNESDAY...DETERIORATING CONDITIONS IN RAIN...WHICH MAY BEGIN AS A LITTLE WET SNOW. THURSDAY...MVFR IN RAIN SHOWERS. && .MARINE... BRISK NORTHWESTERLY WINDS WILL PERSIST THROUGH AT LEAST THIS EVENING AS A RELATIVELY TIGHT SFC PRESSURE GRADIENT WILL REMAIN IN PLACE. THIS WILL RESULT IN A PROLONGED PERIOD OF ADVISORY- WORTHY WINDS AND WAVES FOR THE ICE FREE WATERS OF THE WESTERN TWO THIRDS OF LAKE ONTARIO. BASED ON THE LATEST GUIDANCE HAVE EXTENDED THE SMALL CRAFT ADVISORIES INTO MONDAY MORNING. AFTER THIS..HIGH PRESSURE WILL BUILD ACROSS THE WATERS WITH QUIET CONDITIONS EXPECTED THROUGH MID-WEEK. && .HYDROLOGY... MODEL GUIDANCE CONTINUES TO SUGGEST THAT THERE WILL BE A WARM UP MID-WEEK. HOW LONG THIS LASTS...AND HOW MUCH RAIN COMES WITH THIS WARM UP IS STILL UNCERTAIN. MMEFS ENSEMBLE GUIDANCE SUGGESTS AN INCREASING PROBABLY (AROUND 30 PERCENT) FOR FLOODING ON SOME OF THE BUFFALO CREEKS AND IN THE GENESEE AND ALLEGHENY BASINS. THIS DOES NOT TAKE INTO ACCOUNT THAT THERE ARE ICE JAMS IN PLACE ON SOME OF THE CREEKS WHICH COULD RESULT IN ICE JAM FLOODING IF FLOWS INCREASE RAPIDLY. IF THERE IS FLOOD IT PROBABLY WOULD NOT OCCUR UNTIL AT LEAST WEDNESDAY WHEN TEMPERATURES ARE FORECAST TO WARM INTO THE 40S AND 50S. HYDROLOGIC CONDITIONS ARE DISCUSSED IN THE ESF PRODUCT...AND THE RISK FOR FLOODING MID TO LATE WEEK IS DISCUSSED IN THE HAZARDOUS WEATHER OUTLOOK (HWO). IF THERE IS GOING TO BE FLOODING DUE TO SNOW MELT THIS SPRING...THIS WILL PROBABLY HAVE TO BE THE SYSTEM TO DO IT FOR THE BUFFALO CREEKS...GENESEE...AND ALLEGHENY BASINS. IF FORECAST CONFIDENCE INCREASES IT IS POSSIBLE THAT FLOOD WATCHES WILL BE NEEDED FOR SOME AREAS IN THE WEDNESDAY AND THURSDAY TIMEFRAME. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...LAKE EFFECT SNOW ADVISORY UNTIL 11 AM EDT THIS MORNING FOR NYZ003-004-014. MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR LOZ042-043. && $$ SYNOPSIS...APFFEL NEAR TERM...APFFEL SHORT TERM...THOMAS LONG TERM...CHURCH/THOMAS AVIATION...APFFEL MARINE...APFFEL HYDROLOGY...APFFEL
AREA FORECAST DISCUSSION
NWS BUFFALO NY
305 AM EDT SUN MAR 22 2015 .SYNOPSIS... IN THE WAKE OF A COLD FRONT...MUCH COLDER AIR WILL CONTINUE TO POUR ACROSS OUR AREA OVERNIGHT...WHILE GENERATING SOME ACCUMULATING LAKE SNOWS SOUTH OF LAKE ONTARIO BETWEEN LATE TONIGHT AND SUNDAY MORNING. HIGH PRESSURE WILL THEN BUILD ACROSS THE LOWER GREAT LAKES SUNDAY AND MONDAY. WHILE COLD WEATHER WILL ACCOMPANY THE AREA OF HIGH PRESSURE...SIGNIFICANT WARMING CAN BE EXPECTED BY MID WEEK. && .NEAR TERM /THROUGH TODAY/... AT 300 AM...RADAR/SATELLITE LAKE ENHANCED SNOW SHOWERS SOUTHEAST OF LAKE ONTARIO. SURFACE OBS SHOW A CONVERGENCE BOUNDARY FOCUSED IN THE SAME LOCATION...SOMEWHERE BETWEEN ROCHESTER AND FULTON. UNLIKE TYPICAL LAKE EFFECT EVENTS WHERE THESE BOUNDARIES ARE TYPICALLY LAKE DRIVEN...THIS IS A SYNOPTIC BOUNDARY ON THE SOUTHERN FRINGE OF AN UPPER LEVEL TROUGH. HIGH RESOLUTION MODEL GUIDANCE CAPTURES THIS BOUNDARY WELL WITH THE HOURLY HRRR GRIDS PROVIDING A GOOD PICTURE OF THE LIKELY PROGRESSION OF THE BOUNDARY. HOWEVER...THE 00Z NAM APPEARS TO BE TOO FAR NORTHEAST WITH THE QPF...WITH STEADIEST SNOWS LIKELY TO BE FOCUSED ALONG THE BOUNDARY. AT ANY RATE...THERE IS LITTLE DOUBT THAT THE BOUNDARY WILL DROP SOUTHWARD MID-MORNING. THIS WILL PUSH STEADIER LAKE EFFECT SNOW WESTWARD INTO AND ACROSS MONROE AND ONTARIO COUNTIES BY DAYBREAK. SNOW WILL BE SHORT-LIVED AS THE BOUNDARY CONTINUES ITS SOUTHWARD PUSH. THIS WILL RESULT IN LOWER AMOUNTS WHERE THINGS GET OFF TO A LATER START. STEADIEST BANDS SHOULD BRING 3 TO 5 INCHES TO SOME LOCATIONS IN WAYNE COUNTY...WITH AMOUNTS DROPPING OFF DOWN TO ONLY AN INCH OR TWO IN THE ROCHESTER METRO AREA...AND EVEN LESS TO THE WEST. AFTER THIS BOUNDARY DROPS SOUTH AND WEAKENS LATE THIS MORNING...EXPECT DAYTIME HEATING TO MIX IN DRIER AIR AND DISRUPT MOST OF THIS ACTIVITY. THE AIRMASS IS PROBABLY DRY ENOUGH FOR SOME SUNSHINE UNTIL AFTERNOON CU DEVELOP SOUTH OF THE LAKE. WEAK SHORTWAVE WILL CLIP THE NORTH COUNTRY LATE THIS AFTERNOON WHICH MAY SPARK A FLURRY OR BRIEF SNOW SHOWERS. TEMPERATURES WILL BE ON THE COOL SIDE...WITH HIGHS IN THE MID TO UPPER 20S IN MOST LOCATIONS...WITH SOME AREAS EAST OF LAKE ONTARIO STRUGGLING TO REACH 20. && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... MAINLY QUIET WEATHER EXPECTED IN THE SHORT TERM AS HIGH PRESSURE BUILDS IN ACROSS THE AREA. MONDAY WILL REMAIN A COOL DAY AS LIGHT NORTHERLY WINDS AHEAD OF THE SURFACE HIGH KEEP -12C 850 MB TEMPERATURES LOCKED IN ACROSS WESTERN/CENTRAL NY. HIGH TEMPERATURES ON MONDAY WILL BE STUCK IN THE 20S. LIGHT WINDS AND CLEAR SKIES MONDAY NIGHT AS THE SURFACE HIGH SLIDES OVERHEAD WILL MAKE FOR A COOL NIGHT WITH TEMPERATURES DIPPING INTO THE TEENS AND SINGLE DIGITS. THE COLDEST TEMPERATURES WILL BE IN THE NORTH COUNTRY AND THE HIGHER TERRAIN OF THE WESTERN SOUTHERN TIER. TUESDAY WILL START A SLOW WARMING TREND TOWARD MID-WEEK...AS THE SURFACE HIGH SLIDES EAST OF THE AREA AND THE SOUTHERLY RETURN FLOW RESUMES. 850 MB TEMPERATURES RECOVER INTO THE -2 TO -6C RANGE BY TUESDAY AFTERNOON...WHICH WILL PUSH SURFACE TEMPERATURES INTO THE 30S FOR MOST LOCATIONS. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... THE SYSTEM TO WATCH ENTERS THE PICTURE EARLY WEDNESDAY MORNING AS A SHARP SHORTWAVE IS PROGGED TO LIFT NORTHEASTWARD ACROSS MICHIGAN. A WARM FRONT WILL LIFT NORTHWARD ACROSS THE AREA ON WEDNESDAY...ALLOWING TEMPERATURES TO SURGE INTO THE LOW TO MID 50S FOR MOST OF THE AREA BY THE AFTERNOON. EXPECT TO SEE A SHIELD OF PRECIPITATION IN THE FORM OF RAIN LIFT NORTHWARD ACROSS THE AREA WEDNESDAY MORNING ALONG THE FRONT...BUT THEN WE COULD SEE THE PRECIPITATION WEAKEN/BECOME MORE SHOWERY BY WEDNESDAY AFTERNOON AS WE GET INTO THE WARM SECTOR AND THE SYNOPTIC FORCING MOVES INTO SOUTHERN ONTARIO. MODELS DIVERGE SLIGHTLY BY WEDNESDAY NIGHT INTO THURSDAY ON WHERE AN ELONGATED BAROCLINIC ZONE WILL SET UP. 12Z ECMWF PLACES THIS BOUNDARY SLIGHTLY FARTHER EAST THAN THE 12Z GFS SOLUTION. THE ECMWF SOLUTION WOULD MEAN MUCH LESS RAINFALL FOR WESTERN NY...BEING STUCK ON THE COLD SIDE OF THE BOUNDARY. THE GFS SOLUTION PRODUCES MUCH MORE RAINFALL FOR THE FORECAST AREA WITH A MORE FAVORABLE ORIENTATION OF THE BAROCLINIC ZONE JUST TO OUR WEST. THE POTENTIAL FOR WARMER WEATHER AND POTENTIALLY SIGNIFICANT RAINFALL STILLS BARES WATCHING FOR POSSIBLE HYDROLOGIC ISSUES STILL. BEHIND THIS WEATHER SYSTEM...THE WEEK LOOKS TO CLOSE OUT WITH BELOW NORMAL TEMPERATURES AND THE POTENTIAL FOR SOME LAKE EFFECT SNOW SHOWERS SOUTHEAST OF LAKE ONTARIO AS A BROAD TROUGH CROSSES OVERHEAD. && .AVIATION /07Z SUNDAY THROUGH THURSDAY/... OUTSIDE OF LAKE EFFECT EXPECT VFR CONDITIONS THROUGH THIS AFTERNOON. A DEVELOPING LAKE EFFECT BAND SE OF LAKE ONTARIO WILL DROP SOUTHWARD AND PROBABLY BRING A COUPLE HOURS OF STEADY SNOW TO THE ROCHESTER TERMINAL WITH IFR OR LOWER CONDITIONS. THIS MAY CLIP BUF/IAG/JHW WITH SOME LIGHT SNOW AND MVFR CLOUD DECKS AS A CONVERGENCE BOUNDARY DROPS SOUTH DURING SUNDAY MORNING. HIGH PRESSURE BUILDS SOUTHEASTWARD ACROSS THE LOWER GREAT LAKES ON SUNDAY...THE LAKE SNOWS SHOULD WEAKEN DRAMATICALLY AND SHIFT TO AREAS SOUTHEAST OF LAKE ONTARIO...WHILE GENERAL VFR CONDITIONS BECOME RE-ESTABLISHED ACROSS THE REGION. A WEAK UPPER LEVEL DISTURBANCE IS FORECAST TO CLIP THE NORTH COUNTRY...WHICH MAY LOWER CIGS AND BRING A BRIEF SNOW SHOWER TO ART SUNDAY EVENING. OUTLOOK... SUNDAY NIGHT...MAINLY VFR WITH A CHANCE OF SNOW SHOWERS EAST AND SOUTHEAST OF LAKE ONTARIO. MONDAY AND TUESDAY...VFR. WEDNESDAY...DETERIORATING CONDITIONS IN RAIN...WHICH MAY BEGIN AS A LITTLE WET SNOW. THURSDAY...MVFR IN RAIN SHOWERS. && .MARINE... BRISK NORTHWESTERLY WINDS WILL PERSIST THROUGH AT LEAST THIS EVENING AS A RELATIVELY TIGHT SFC PRESSURE GRADIENT WILL REMAIN IN PLACE. THIS WILL RESULT IN A PROLONGED PERIOD OF ADVISORY- WORTHY WINDS AND WAVES FOR THE ICE FREE WATERS OF THE WESTERN TWO THIRDS OF LAKE ONTARIO...AS IS OUTLINED BELOW. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...LAKE EFFECT SNOW ADVISORY UNTIL 11 AM EDT THIS MORNING FOR NYZ003-004-014. MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EDT MONDAY FOR LOZ042-043. && $$ SYNOPSIS...JJR/RSH NEAR TERM...APFFEL SHORT TERM...CHURCH LONG TERM...CHURCH AVIATION...APFFEL MARINE...JJR/RSH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
325 AM EDT SUN MAR 22 2015 .SYNOPSIS...A WEAK COLD FRONT WILL MOVE ACROSS CENTRAL NC THIS MORNING...FOLLOWED BY THE PASSAGE OF A STRONGER COLD FRONT TONIGHT. A SERIES OF WEAK AREAS OF LOW PRESSURE WILL TRACK EAST ACROSS THE DEEP SOUTH AND OFF THE SOUTH ATLANTIC COAST THROUGH MONDAY NIGHT. HIGH PRESSURE WILL EXTEND INTO THE REGION FROM THE NORTHEAST ON TUESDAY AND WEDNESDAY BEFORE THE NEXT COLD FRONT APPROACHES THE REGION FROM THE WEST ON THURSDAY. && .NEAR TERM /SUNDAY THROUGH MONDAY/... AS OF 325 AM SUNDAY... A SOUTHERN STREAM SHORT WAVE TROUGH LOCATED OVER TX AND OK EARLY THIS MORNING WILL SHIFT EAST AND REACH THE SOUTH ATLANTIC COAST BY LATE MONDAY AFTERNOON. FURTHER ALOFT...A STRONG SUBTROPICAL JET WITH A MOISTURE CONNECTION FROM THE EASTERN PACIFIC WILL EXTEND ACROSS THE SOUTHEAST DURING THE PERIOD WITH SPEEDS AT TIMES IN EXCES OF 125KTS. AT THE SURFACE...A SERIES OF WEAK SURFACE LOWS WILL MOVE ACROSS THE NORTHERN GULF COAST AND INTO THE ATLANTIC NEAR THE FL/GA COAST. FINALLY...A SOUTHWARD ADVANCING COLD FRONT LOCATED ACROSS NORTHERN VA AT 06Z WILL DROP INTO CENTRAL NC LATER THIS MORNING WITH A SECONDARY A STRONGER FRONT PUSING INTO NC LATE TONIGHT. TODAY WILL FEATURE MAINLY CLOUDY SKIES ACROSS CENTRAL NC ALTHOUGH THE CLOUDINESS WILL BE OF A MID AND HIGH NATURE THIS MORNING EVERYWHERE RESULTING IN A RELATIVELY BRIGHT OVERCAST. REGIONAL RADAR SHOWS AN AREA OF LIGHT RAIN EXTENDING ACROSS AL AND GA AND NOW CROSSING THE SAVANNAH RIVER INTO SC. THE NORTHERN EXTENT OF THIS PRECIPITATION IS VERY LIGHT AND FALLING FROM MID LEVEL CLOUDS. DETERMINISTIC NWP GUIDANCE HAS BEEN FAIRLY CONSISTENT IN DEPICTING A SHARP BOUNDARY BETWEEN THE RAIN SHIELD RAIN AND DRY WEATHER TO THE NORTH WITH THE BOUNDARY LIKELY SETTING UP JUST NORTH OF THE NORTH CAROLINA-SOUTH CAROLINA BORDER. GIVEN RADAR TRENDS AND HIGHER RESOLUTION GUIDANCE INCLUDING THE HRRR AND THE HI RES WINDOW RUNS...HAVE INCREASED POPS AND QPF AMOUNTS FOR THE SOUTHERN MOST ROW OF COUNTIES IN NC. STILL...CONFIDENCE IN HOW MUCH AND HOW FAR NORTH THE PRECIPITATION WILL FALL IS LIMITED BUT IT APPEARS THAT MEASURABLE RAIN TODAY WILL REMAIN SOUTH OF THE U.S. 64 CORRIDOR. EVEN WHERE THERE IS A GOOD CHANCE OF RAIN SUCH AS FAYETTEVILLE... GUIDANCE IS VARYING IN HOW MUCH. FOR EXAMPLE THE 21Z SREF 30-HOUR FORECAST FOR FAY NOTES 4 OF THE 21 MEMBERS PRODUCING MORE THAN AN INCH OF PRECIPITATION WHILE 6 MEMBERS HAVE LESS THAN 3 HUNDRETHS AND THE START TIME OF THE PRECIPITATION VARIES JUST AS WIDELY. EVEN WITH OVERCAST SKIES AND SOME SLIGHTLY COOLER AIR FILTERING IN FROM THE NORTHEAST...HIGHS TODAY SHOULD GENERALLY RANGE IN THE LOWER TO MID 60S WITH THE COOLEST TEMPS IN THE NORTHEAST WITH HIGHS AROUND 60 AND A FEW LOCATIONS ACROSS THE WESTERN PIEDMONT FLIRTING WITH THE UPPER 60S. THE WEAK WAVES OF LOWER PRESSURE WILL CONTINUE TO SKIRT BY TO OUR SOUTH TONIGHT AND MONDAY. A SECONDARY COLD FRONT WILL PUSH INTO NC FROM THE NORTHEAST LATE TONIGHT AND EARLY MONDAY WITH NOTABLY COOLER AN DRIER AIR. WIDESPREAD OVERCAST CONDITIONS ARE EXPECTED TONIGHT INTO MONDAY WITH SOME THINNING OF THE CLOUD COVER EXPECTED LATE IN THE DAY ACROSS THE NORTHERN AND WESTERN PIEDMONT. CHANCES OF LIGHT RAIN WILL CONTINUE ACROSS THE SOUTHEAST. LIGHT NORTHEAST AND EASTERLY WINDS WILL BECOME NORTHEAST AND INCREASE LATE TONIGHT AND MONDAY BEHIND THE FRONT WITH SOME GUSTS REACHING THE 15-20 MPH RANGE. LOWS TONIGHT WILL RANGE FROM AROUND 40 TO 45 WITH HIGHS ON MONDA IN THE LOWER 50S. -BLAES && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... AS OF 320 AM SUNDAY... MONDAY NIGHT THROUGH TUESDAY... S/W IN THE SOUTHERN STREAM WILL CONTINUE TO SHEAR OUT AS IT PROGRESSES EASTWARD ACROSS SOUTH CAROLINA. MEANWHILE A PARENT SFC HIGH OVER NEW ENGLAND WILL CONTINUE TO NOSE/BUILD SOUTHWARD INTO THE CAROLINAS. THIS SFC WEATHER SYSTEM WILL CONTINUE TO ADVECT A COOLER/DRIER LOW LEVEL AIR MASS INTO THE REGION. ANY PRECIP OVER THE FAR SOUTH-SE SECTIONS OF THE FORECAST AREA WILL GRADUALLY DIMINISH AS LIFT ASSOCIATED WITH THE S/W WEAKENS. MIN TEMPS MONDAY NIGHT MID-UPPER 30S. THE SURFACE PATTERN FOR TUESDAY WITH A PARENT HIGH CENTERED OVER NEW ENGLAND AND SLY AND/OR BACKING FLOW IN THE 850MB-700MB LAYER WIL SUPPORT A WEAK CLASSICAL COLD AIR DAMMING EVENT FOR TUESDAY. CONSIDERABLE CLOUDINESS AND A SFC NE WIND SHOULD LEAD TO AFTERNOON TEMPS 7-10 DEGREES BELOW NORMAL (AT LEAST). TUESDAY NIGHT...INCREASING SLY FLOW IN THE 925-850MB SHOULD CAUSE PATCHES OF DRIZZLE TO OCCUR ALONG WITH EXTENSIVE LOW CLOUDS. MIN TEMPS UPPER 30S-LOWER 40S. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 320 AM SUNDAY... WEDNESDAY THROUGH SATURDAY... UPPER AIR PATTERN WILL EVOLVE THIS PERIOD INTO A PATTERN SIMILAR TO THE LAST HALF OF TIS WINTER SEASON WITH A PRONOUNCED RIDGE IN THE WEST AND A TROUGH OVER TEH EAST. THE LEAD S/W INITIATING THIS PATTERN EVOLUTION WILL CROSSING THE PLAINS STATES WEDNESDAY. CLOSER TO HOME...SFC RIDGE WILL DRIFT OFFSHORE IN RESPONSE TO THE APPROACHING S/W...WITH A SLY LOW LEVEL FLOW INCREASING ACROSS OUR REGION. THIS FLOW OVER THE COOL STABLE DOME OF AIR LEFTOVER FROM THE CAD EVENT TUESDAY SHOULD CAUSE EXTENSIVE CLOUDINESS WEDNESDAY MORNING ALONG WITH PATCHES OF DRIZZLE OR DENSE FOG. MODELS HINT AT SOME EXTENSION OF THE RIDGE PERSISTING OVER OUR REGION SO THE LOW CLOUDS MAY HOLD ON LONGER THAN PREDICTED BY THE MODELS WHICH MAY CAUSE HIGH TEMPS WEDNESDAY TO BE COOLER THAN FORECAST. HAVE LOWERED MAX TEMPS ABOUT A CATEGORY FROM THE PREVIOUS FORECAST AND THIS MAY NOT BE ENOUGH. THIS WILL NEED TO BE RE- EVALUATED WITH LATER MODEL RUNS. WITH THE INCREASING SLY FLOW WILL COME A THREAT FOR A FEW SHOWERS WEDNESDAY. HAVE INTRODUCED A SLIGHT CHANCE POP FOR WEDNESDAY. LEAD S/W WILL LIFT WELL NORTH OF OUR REGION THROUGH A SHEAR AXIS AND SFC FRONT WILL EXTEND SOUTHWARD INTO THE TN VALLEY THURSDAY MORNING...MOVING INTO THE CAROLINA PIEDMONT BY LATE THURSDAY- THURSDAY EVENING. 00Z GFS DEPICTS A SLIGHTLY UNSTABLE AIR MASS WITH SFC BASED CAPE VALUES 1000-1400 J/KG AND MUCAPE JUST SHY OF 1000 J/KG. BULK SHEAR INCREASES TO 35-45 KTS BY LATE IN THE DAY. THE CAPE VALUES MAY BE ACHIEVED IF ENOUGH HEATING OCCURS WHICH IS QUESTIONABLE AS CONSIDERABLE CLOUDINESS FROM RESIDUAL CAD MAY STILL BE AN ISSUE. WILL MAINTAIN CHANCE POPS FOR THURSDAY AFTERNOON- THURSDAY NIGHT ALONG WITH A MENTION OF THUNDER BASED ON THE ABOVE CONVECTIVE PARAMETERS. HIGH TEMPS THURSDAY COULD END UP BEING 3-5 DEGREES COOLER...BASED ON WHETHER CLOUDS/SHOWERS MORE EXTENSIVE THAN CURRENT THINKING. MILD WEDNESDAY NIGHT AHEAD OF THE FRONT WITH OVERNIGHT TEMPS IN THE MID-UPPER 50S. HIGHS THURSDAY LOWER 70S NW TO UPPER 70S SE. UNSETTLED WEATHER EXPECTED FRIDAY THROUGH EARLY SATURDAY AS A SERIES OF S/WS ALOFT DIG THE UPPER TROUGH OVER THE EASTERN U.S. WHILE FRONTAL PASSAGE EXPECTED THURSDAY NIGHT...COULD SEE POCKETS OF LIGHT RAIN TRAVERSE ACROSS THE REGION FRIDAY...FRIDAY NIGHT AND POSSIBLY SATURDAY ASSOCIATED WITH THE S/WS ALOFT. UPPER TROUGH OVERHEAD WILL LEAD TO A PERIOD OF BELOW NORMAL HIGH TEMPS...AVERAGING 10-15 DEGREES BELOW NORMAL. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... AS OF 240 AM SUNDAY... 24 HOUR TAF PERIOD...A SERIES OF WEAK AREAS OF LOW PRESSURE WILL HELP GENERATE A LARGE AREA OF LIGHT RAIN ACROSS THE DEEP SOUTH THROUGH MONDAY. THE MAJORITY OF THIS PRECIPITATION WILL FALL SOUTH OF THE RAH TERMINALS WITH A RELATIVELY SHARP BOUNDARY BETWEEN RAIN AND NO RAIN LIKELY TO EXTEND NEAR AND JUST NORTH OF THE NORTH AND SOUTH CAROLINA BORDER. SOME OF THE RAIN WILL LIKELY REACH THE KFAY TERMINAL LATE THIS AFTERNOON OR EARLY THIS EVENING WITH THE PRECIPITATION LIKELY REMAINING SOUTH OF THE REMAINDER OF THE TERMINALS FOR MOST OF THE OVERNIGHT. CONFIDENCE IN HOW MUCH AND HOW FAR NORTH THE PRECIPITATION WILL FALL IS LOW. AT LEAST INITIALLY MUCH OF THE PRECIPITATION WILL FALL FROM MID LEVEL CLOUDS AND THE EXTENT OF CEILING REDUCTION AT KFAY IS UNCERTAIN BUT FEEL IT IS PROBABLE THAT AT LEAST A PERIOD OF MVFR CIGS AND VSBYS WILL OCCUR THIS EVENING. AFTER MIDNIGHT...LOW LEVEL MOISTURE WILL INCREASE AND MORE WIDESPREAD LOW CEILINGS AT 2500-3500 FEET ARE EXPECTED ACROSS ALL OF THE TERMINALS. CALM OR VERY LIGHT SOUTHWESTERLY WINDS ARE EXPECTED EARLY THIS MORNING AND THEN BECOME NORTHEASTERLY WITH THE PASSAGE OF A WEAK COLD FRONT THIS MORNING. OUTLOOK... ANOTHER COLD FRONT WILL MOVE THROUGH CENTRAL NC TONIGHT PRODUCING A SURGE OF STRONGER NORTHEAST WINDS INTO MONDAY WITH A PERIOD OF MVFR CEILINGS IN STRATUS. THE POTENTIAL FOR SOME LIGHT RAIN MAINLY SOUTH OF KRDU AND KRWI PERSISTS LATE TONIGHT INTO MONDAY AFTERNOON. REDUCED CIGS ARE LIKELY TO PERSIST FROM MONDAY INTO TUESDAY MORNING. ADVERSE AVIATION CONDITIONS ARE LIKELY TO DEVELOP WEDNESDAY AND WEDNESDAY NIGHT WITH A MOIST SOUTHEAST FLOW PRODUCING LOW STRATUS AND SOME RAIN. ANOTHER ROUND OF ADVERSE CONDITION ARE PROBABLY ON THURSDAY AS A COLD FRONT PRODUCES SCATTERED SHOWERS AS IT APPROACHES THE REGION. -BLAES && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BLAES NEAR TERM...BLAES SHORT TERM...WSS LONG TERM...WSS AVIATION...BLAES
AREA FORECAST DISCUSSION
NWS BISMARCK ND
414 AM CDT SUN MAR 22 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM CDT SUN MAR 22 2015 FORECAST HIGHLIGHTS AND CHALLENGES IN THE SHORT TERM PERIOD WILL BE THE THREAT FOR FREEZING PRECIPITATION ACROSS THE SOUTHWEST THIS MORNING...AND HOW PRECIPITATION EVOLVES EASTWARD. CURRENTLY...ACTIVE ZONAL FLOW ALOFT WITH A POTENT SHORT WAVE MOVING EAST INTO SOUTH CENTRAL CANADA AND ANOTHER MORE SUBTLE/EMBEDDED FEATURE MOVING EAST ACROSS NORTHERN WYOMING/SOUTHEASTERN MONTANA. ASSOCIATED SURFACE LOWS OVER SOUTHERN SASKATCHEWAN AND EASTERN WY/SOUTHWESTERN SD RESPECTIVELY. THE SOUTHERN MOST WAVE IS OUR MAIN CONCERN...GENERATING PRECIPITATION FROM SOUTHEASTERN MONTANA EAST TO ACROSS SOUTHWESTERN NORTH DAKOTA. THERMAL PROFILES AND SFC TEMPERATURES INDICATING LIGHT FREEZING RAIN IS LIKELY FALLING. MADE A FEW CALLS TO THE SOUTHWEST WHICH INDICATED NO IMPACTS AS SO FAR THE LIGHT FREEZING PRECIP IS ONLY TRACING OUT. A VERY DRY EASTERLY FLOW IS KEEPING THE BOUNDARY LAYER RATHER DRY FROM THE SURFACE UP TO 5-7K FT AGL...SO ANY MOISTURE REACHING THE GROUND SHOULD BE LIMITED. WILL MAINTAIN LIKELY POPS SOUTHWEST INTO SOUTH CENTRAL. HAVE A SPECIAL WEATHER STATEMENT OUT NOW FOR THE FREEZING RAIN POTENTIAL...AND WILL CONTINUE WITH THIS UNLESS WE HEAR OF MORE IMPACTS AND A FREEZING RAIN ADVISORY BECOMES NEEDED. MORE RADAR RETURNS ACROSS THE NORTH...BUT AGAIN WITH CLOUD BASES AT ROUGHLY 8-10K AGL...ANTICIPATE LITTLE IS REACHING THE GROUND SO WILL KEEP POPS BELOW LIKELY THERE. MODELS HAVING A HARD TIME THIS MORNING WITH EACH RUN OF THE HRRR AND NAM MODELS DIFFERENT. BASICALLY WENT WITH A BLEND WHICH FOLLOWS THE 00Z ECMWF AND LATEST 06Z NAM RATHER WELL. THIS CONFINES HIGHER POPS THIS MORNING TO MY SOUTHERN COUNTIES...ALONG TO SOUTH OF INTERSTATE 94. MAIN THREAT FOR FREEZING RAIN WILL REMAIN WEST OF THE MISSOURI RIVER ACROSS MY SOUTHWEST THROUGH MID MORNING...WITH THERMAL PROFILES SUGGESTING ALL SNOW TO THE EAST. SURFACE FRONTAL BOUNDARY MOMENTARILY STALLS ACROSS THE WEST THIS AFTERNOON...WITH A WESTERLY WIND TO THE WEST AND SOUTHERLY WIND TO THE EAST. NAM AND RAP ARE INDICATING POSSIBLE STRATUS DEVELOPMENT ALONG TO EAST OF THE BOUNDARY LATER TODAY INTO THIS EVENING AS THE SOUTH/SOUTHEASTERLY FLOW TRANSPORTS MOISTURE NORTH. THUS WILL KEEP SKY COVER ELEVATED ABOVE MOSTLY SUNNY/MOSTLY CLEAR. CONFIDENCE NOT HIGH WITH THIS PLAYING OUT WITH MODELS STRUGGLING THE PAST FEW RUNS. AFOREMENTIONED STRONG SHORT WAVE CUTTING EAST ACROSS SOUTH CENTRAL CANADA WILL TURN SOUTHEAST AND MOVE INTO FAR NORTHEASTERN ND/NORTHERN MINNESOTA THIS SUNDAY NIGHT. PRECIPITATION IN THE FORM OF SNOW MAY GRAZE MY FAR NORTHEAST SO WILL MAINTAIN A LOW POP THERE TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 414 AM CDT SUN MAR 22 2015 THE PRIMARY CONCERN IN THE LONG TERM PERIOD WILL BE THE POTENT STORM MONDAY NIGHT INTO TUESDAY. THE LATEST MODEL SUITE CONTINUES TO ADVERTISE A POTENT STORM SYSTEM ACROSS THE NORTHERN PLAINS MONDAY NIGHT INTO TUESDAY. DETAILS REGARDING THE EXACT TRACK OF THE SYSTEM REMAIN ELUSIVE WITH THE 00Z GFS AND ECMWF STILL SHOWING DIFFERENCES...AND LARGE SPREAD INDICATED BY THE GEFS. THE ECMWF AND GFS BOTH SUGGEST TWO SURFACE LOWS WILL DEVELOP...HOWEVER THEY DIFFER ON THE PROGRESSION OF THE NORTHERN MOST LOW. THE ECMWF KEEPS THE LOWS SEPARATE WITH ONE TRACKING INTO CANADA...WHILE THE GFS MERGES THE LOWS IN MINNESOTA / WISCONSIN. HAVE AGAIN GONE WITH A BLENDED MODEL SOLUTION DUE TO THE UNCERTAINTY. THIS MAINTAINS SOME CONSISTENCY IN THE FORECAST WITH WARM AIR AND RAIN EXPECTED ACROSS MUCH OF CENTRAL AND WESTERN NORTH DAKOTA DURING THE MORNING AND AFTERNOON TUESDAY. THE EXCEPTION COULD BE THE FAR NORTH AND WEST WHERE COLDER AIR MAY FAVOR SNOW. COLD AIR ARRIVES BEHIND THE LOW TUESDAY NIGHT...WHICH SUPPORTS A THERMAL PROFILE TRANSITIONING TO SNOW ACROSS THE FORECAST AREA. CONFIDENCE IN PRECIPITATION AND / OR SNOW AMOUNTS REMAINS LOW DUE TO THE LARGE DIFFERENCES IN MODEL SOLUTIONS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 414 AM CDT SUN MAR 22 2015 FREEZING RAIN WILL BE POSSIBLE THROUGH 12-14Z FOR KISN-KDIK...ALL SNOW EAST FOR KMOT-KBIS-KJMS. CURRENT VFR CONDITIONS NOW EXPECTED TO MAINLY PERSIST. IFR CONDITIONS POSSIBLE FOR KBIS-KJMS AS SNOW DEVELOPS LATER THIS MORNING. MODELS DO INDICATE A CORRIDOR OF LOW STRATUS DEVELOPING DURING THE DAY SUNDAY INTO SUNDAY NIGHT CENTRAL IMPACTING KBIS-KMOT-KJMS. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...NH LONG TERM...CK AVIATION...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
330 AM CDT SUN MAR 22 2015 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 330 AM CDT SUN MAR 22 2015 SNOW CHANCES AND AMOUNTS WILL BE THE CHALLENGE. 00Z MODELS IN DECENT AGREEMENT...ALTHOUGH THERE ARE SOME DIFFERENCES TODAY. RIDGING REMAINS IN PLACE ACROSS THE REGION WITH DRY LOW LEVEL EASTERLY FLOW. MODEL TRENDS INDICATE LESS INTERACTION BETWEEN NORTHERN AND SOUTHERN UPPER WAVES...LEADING TO FAR LESS QPF ACROSS THE WESTERN FA TODAY. IN FACT...THE LATEST HRRR AND RAP GUIDANCE INDICATES THAT QPF WILL REMAIN OUTSIDE OF THE FA WITH STRONGER RIDGING/MORE DRY AIR. TRENDED THE FORECAST IN THIS DIRECTION...WITH MAYBE AN INCH OR TWO OF SNOW ACROSS THE FAR SOUTHERN FA. WILL CONTINUE TO MONITOR TRENDS AND MAY EVENTUALLY REMOVE ALL POPS FOR TODAY. WITH THIS...MODELS ARE TRENDING WARMER TODAY (THINNER CLOUD COVER)...AND FOLLOWED THIS TREND IN THE FORECAST. TONIGHT...THE NORTHERN UPPER WAVE IS QUITE STRONG...AND MODELS HAVE BEEN CONSISTENT SPREADING SNOW INTO PARTS OF THE NORTHERN FA (WITH AN INCH OR TWO POSSIBLE). MONDAY...REGION WILL BE BETWEEN SYSTEMS ALONG WITH WARM AIR ADVECTION AHEAD OF THE NEXT SYSTEM. SHOULD BE A RELATIVELY QUIET DAY WITH MAX TEMPS APPROACHING OR INTO THE 40S. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAR 22 2015 MONDAY NIGHT-TUESDAY NIGHT...STRONGER SYSTEM WILL AFFECT THE REGION...MOST LIKELY LATER TUESDAY INTO TUESDAY NIGHT. CONFIDENCE IS HIGH THAT SOMETHING IS GOING TO OCCUR...ALTHOUGH MODELS ARE ALL OVER THE PLACE WITH DETAILS SO EXACTLY WHAT OCCURS IS HIGHLY QUESTIONABLE. GENERALLY...THE REGION WILL BE WITHIN AN INVERTED TROUGH WITH RAIN EVENTUALLY CHANGING TO SNOW. SOME MODELS ARE INDICATING OVER A FOOT OF SNOW...WITH OTHERS FAR LESS (OR ALMOST NOTHING). MUCH WILL DEPEND ON HOW THE SYSTEM EVOLVES...AND WHEN/WHERE THE SOUTHERN SFC LOW STRENGTHENS (WHICH WILL INFLUENCE THE STRENGTH OF THE INVERTED TROUGH AND THUS QPF AMOUNTS). FOR NOW...THE BEST THING TO SAY IS RAIN CHANGING TO SNOW WITH SOME ACCUMULATIONS POSSIBLE. WEDNESDAY-SATURDAY...THE BACKSIDE OF THE FULLY DEVELOPED CLOSED- LOW SYSTEM OVER WISCONSIN AND MOVING EASTWARD WILL BRING AN END TO THE PRECIPITATION OVER WEST-CENTRAL MINNESOTA WITH THE NORTHERLY WINDS ADVECTING IN SOME COOLER DAYTIME TEMPERATURES IN THE 30S AND LOWS IN THE TEENS FOR WEDNESDAY. A SURFACE HIGH PRESSURE SYSTEM WILL BE IN PLACE OVER THE AREA BY THURSDAY AHEAD OF A BUILDING UPPER-AIR RIDGE ON THE WEST COAST. THAT HIGH WILL BE SHIFTING TO THE EAST WITH SOME SOUTHERLY WINDS ON ITS BACKSIDE BRINGING IN SOME WARMER AIR FOR FRIDAY AND SATURDAY. HOWEVER...AN EMBEDDED UPPER-AIR SHORT WAVE EMBEDDED IN THE NORTHWEST FLOW FROM WESTERN RIDGE WILL BRING GOOD CHANCES FOR WEEKEND PRECIPITATION AS ANOTHER SURFACE LOW SPINS UP TO TRAVERSE THE REGION OVER THE WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1139 PM CDT SAT MAR 21 2015 REALLY NO CHANGE IN CIGS ANTICIPATED AS DRY LOWER LEVELS SHOULD LIMIT ANY LOWER CLOUD DEVELOPMENT. LOW CONFIDENCE IN SNOW POTENTIAL ACROSS TAF SITES TOMORROW SO LEFT DRY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...TG LONG TERM...TG/LUKES AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
125 AM CDT SUN MAR 22 2015 .UPDATE... ISSUED AT 125 AM CDT SUN MAR 22 2015 POOR MODEL PERFORMANCE THE PAST FEW DAYS HAS LED TO SOME RATHER BIG MODIFICATIONS FOR THE SHORT TERM FORECAST TONIGHT THROUGH SUNDAY. HIGH RES NMM/ARW...ALONG WITH THE HRRR AND SREF/NAM BRING THE HEAVIER PRECIPITATION THIS MORNING NOW ACROSS MY SOUTHERN COUNTIES WITH ONLY SCATTERED ACTIVITY NOW ACROSS THE NORTH. REGIONAL RADAR SUPPORTS THIS. POPS WERE ADJUSTED. MAIN CONCERN IS THE POTENTIAL FOR FREEZING RAIN ACROSS PORTIONS OF THE SOUTHWEST. ALONG THE MONTANA BORDER AIR TEMPERATURES WILL REMAIN WARM ENOUGH TO KEEP PRECIPITATION ALL RAIN. FARTHER TO THE EAST FROM DUNN COUNTY SOUTH THROUGH STARK...HETTINGER...AND ADAMS COUNTIES...SURFACE TEMPERATURE FORECAST ALONG WITH THERMAL PROFILES WILL SUPPORT FREEZING RAIN...WITH ICE ACCUMULATIONS LIKELY. STILL SOME UNCERTAINTY WHETHER TEMPERATURES WILL WARM OR NOT AS PRECIPITATION DEVELOPS INTO THIS AREA FROM THE WEST. PLAN RIGHT NOW IS TO HIGHLIGHT THE POTENTIAL WITH A SPECIAL WEATHER STATEMENT AND MONITOR IN CASE A FREEZING RAIN ADVISORY BECOMES NEEDED. PRECIP TYPE WILL BECOME ALL SNOW AS THE AREA OF PRECIPITATION TRACKS FARTHER EAST INTO MORTON AND GRANT COUNTIES AND POINTS EAST. ACCUMULATIONS ARE EXPECTED IF HIGH RES MODELS HOLD TRUE...RIGHT NOW AROUND AN INCH. UPDATE ISSUED AT 903 PM CDT SAT MAR 21 2015 RADAR SHOWS STEADY LIGHT SNOW IN ROLLA THAT WILL LAST FOR A FEW HOURS. THEN FOCUS WILL TURN TO THE WEST WHERE LOW LEVEL WARM ADVECTION AND FRONTAL BOUNDARY WILL FOCUS LIGHT RAIN THIS EVENING...WITH A WINTRY MIX OF RAIN...FREEZING RAIN OR SLEET AND SOME SNOW POSSIBLE AFTER MIDNIGHT. NEW NAM NOW PLACES MOST OF THE PRECIP IN CANADA. BUT BOTH NAM AND HRRR GENERATE A RAIN AREA SOUTHWEST TONIGHT. STILL MUCH UNCERTAINTY AT THIS LATE TIME. AM MORE COMFORTABLE WITH LESS FREEZING RAIN AND MORE RAIN THROUGH MIDNIGHT...WILL MONITOR AFTER MIDNIGHT BUT IF NAM IS RIGHT MOST OF PRECIP WILL BE NORTH IN CANADA. UPDATE ISSUED AT 646 PM CDT SAT MAR 21 2015 CLOUDS ARE INCREASING WEST ASSOCIATED WITH A SHORTWAVE TROUGH MOVING INTO THE NORTHERN PLAINS. WARM AIR ACROSS EASTERN MONTANA WILL MOVE OVER COOLER SURFACE AIR ACROSS WESTERN NORTH DAKOTA LATER TONIGHT. THIS COULD CREATE SOME FREEZING PRECIPITATION. SURFACE TEMPERATURES TO SAY THE LEAST WILL BE CRITICAL FOR THIS. AT 6 PM CROSBY RAWS IS 27 AND WILLISTON 41. WILL CONTINUE TO MONITOR. SO FAR CURRENT FORECAST LOOKS OK. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 320 PM CDT SAT MAR 21 2015 CURRENT SURFACE ANALYSIS PLACES LOW STRETCHING GENERALLY ALONG THE LEE SIDE OF THE ROCKIES WHILE HIGH STRETCHES FROM THE RED RIVER VALLEY UP INTO MANITOBA. UPPER LEVEL ANALYSIS PLACES RIDGE OVER EASTERN MONTANA UP INTO SASKATCHEWAN/ALBERTA WHILE DEEP LOW SPINS NEAR JAMES BAY BRINGING NORTHWEST FLOW TO OUR AREA. POTENT SHORT WAVE OVER THE NORTHWESTERN CONUS CONTINUES ITS EASTWARD PUSH. SOME LIGHT SNOW CONTINUES TO LINGER OVER THE NORTH CENTRAL PART OF THE STATE IN WEAK ISENTROPIC LIFT...THOUGH AREA WEBCAMS INDICATE VERY LITTLE IF ANY ACCUMULATION. FOR THE REST OF THIS AFTERNOON INTO TONIGHT...AFOREMENTIONED LIGHT SNOW OVER THE NORTH WILL CONTINUE TO SLOWLY DISSIPATE. OTHERWISE...MAIN CONCERN WILL BE THE SHORT WAVE OVER THE NORTHWESTERN CONUS MAKING ITS ADVANCE TOWARDS THE AREA. SHORT WAVE WILL PUSH ITS WAY OVER THE RIDGE...WITH PRECIPITATION DEVELOPING OVER THE WEST THIS EVENING AND SPREADING EAST OVERNIGHT. MOST LOCATIONS SHOULD SEE SNOW...OR POSSIBLY SOME RAIN OVER THE WEST WHERE TEMPERATURES WILL BE SLOWLY FALLING. LATER TONIGHT...FORECAST SOUNDINGS SUGGEST THE POSSIBILITY OF A LITTLE SLEET OF FREEZING RAIN MAINLY OVER THE FAR WEST SO HAVE ADDED A MENTION OF THAT. ON SUNDAY...SNOW WILL DIMINISH FROM WEST TO EAST AS SHORT WAVE CONTINUES ITS PROGRESSION THROUGH THE AREA. TOTAL SNOW AMOUNTS FROM THIS SYSTEM STILL LOOK TO BE THE HIGHEST MAINLY OVER NORTH CENTRAL NORTH DAKOTA INTO PARTS OF THE NORTHWEST. TEMPERATURES WILL REMAIN THE COOLEST MAINLY OVER THE CENTRAL PART OF THE STATE WHILE TO THE WEST EXPECT TEMPERATURES TO REBOUND AS SYSTEM MOVES TO THE EAST. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 320 PM CDT SAT MAR 21 2015 A POTENT SYSTEM COULD IMPACT THE REGION MIDWEEK. THE LATEST SUITE OF MODELS CONTINUES TO SLOW DOWN THE PROGRESSION OF OUR MID WEEK SYSTEM. PREVIOUS RUNS HAD PRECIPITATION BEGINNING MONDAY NIGHT WEST. HOWEVER...IT NOW APPEARS PRECIPITATION WILL BE DELAYED UNTIL TUESDAY. THERE IS STILL A LOT OF UNCERTAINTY IN THE EXACT TRACK OF THIS SYSTEM. OVER THE PAST TWO MODEL RUNS THE GFS HAS ONCE AGAIN COMPLETELY FLIP FLOPPED FROM A NORTHERN SOLUTION TO A SOUTHERN SOLUTION. THE ECMWF REMAINS FAIRLY CONSISTENT...WITH AN EVER SO SLIGHTLY FURTHER NORTH TRACK THAN THE 00 UTC RUN. THE GFS ENSEMBLE SPREAD IS RATHER WIDE...WITH THE CENTER OF THE LOW ANYWHERE FROM SOUTHERN CANADA TO NORTHERN IOWA. FOR THIS FORECAST...UTILIZED A BLEND OF THE OPERATIONAL MODELS. THIS LED TO GENERALLY LESSER AMOUNTS OF SNOW SOUTH OF HIGHWAY 2. IT APPEARS THAT MOST OF WESTERN AND CENTRAL NORTH DAKOTA WILL SEE TEMPERATURES WARM ENOUGH FOR ALL RAIN DURING THE MORNING AND AFTERNOON HOURS...AND THEN SEE A TRANSITION FROM NORTH TO SOUTH TO ALL SNOW OVERNIGHT. AT THIS TIME IT APPEARS THAT ONLY LOCATIONS NORTH OF HIGHWAY 2 WILL SEE BELOW FREEZING TEMPERATURES THROUGHOUT TUESDAY AND WEDNESDAY. TEMPERATURES WILL VARY GREATLY BASED ON THE EXACT TRACK OF THE LOW PRESSURE CENTER. THEREFORE...HEAVY SNOWFALL IS POSSIBLE WITH THIS SYSTEM AS STRONG FRONTOGENESIS...DEFORMATION BANDING...AND POTENTIAL TROWL SET UP ACROSS SOME PORTION OF NORTH DAKOTA...BUT AT THE SAME TIME IT COULD TURN OUT TO BE SIMPLY A HEAVY RAIN EVENT FOR WESTERN AND CENTRAL NORTH DAKOTA. THERE IS JUST TOO MUCH UNCERTAINTY AT THIS TIME TO NAIL DOWN SPECIFIC LOCATIONS AND SNOWFALL AMOUNTS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 125 AM CDT SUN MAR 22 2015 FREEZING RAIN WILL BE POSSIBLE THROUGH 12Z FOR KISN-KDIK...ALL SNOW EAST FOR KMOT-KBIS-KJMS. CURRENT VFR CONDITIONS NOW EXPECTED TO MAINLY PERSIST. IFR CONDITIONS POSSIBLE FOR KBIS-KJMS AS SNOW DEVELOPS LATER THIS MORNING. MODELS DO INDICATE A CORRIDOR OF LOW STRATUS DEVELOPING DURING THE DAY SUNDAY INTO SUNDAY NIGHT CENTRAL IMPACTING KBIS-KMOT-KJMS. SOME UNCERTAINTY WITH THIS RIGHT NOW. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...NH SHORT TERM...JJS LONG TERM...AJ AVIATION...NH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1149 PM CDT SAT MAR 21 2015 .UPDATE... ISSUED AT 902 PM CDT SAT MAR 21 2015 THE MAIN FOCUS IS ON THE SNOW FOR TOMORROW IN REGARD TO WHEN IT WILL START AND WHETHER IT WILL START OUT AS RAIN OR SNOW. VERY DRY AIR IN PLACE IN THE LOW LEVELS THANKS TO NORTHEASTERLY FLOW ALONG THE SOUTHERN PERIPHERY OF A RIDGE OF HIGH PRESSURE. HIGH CLOUDS ARE MOVING IN AND WILL THICKEN THROUGH THE NIGHT. AS WE APPROACH DAYBREAK TOMORROW MORNING MUCH OF THE MESO-GUIDANCE...SUCH AS THE RAP/HRRR/HOPWRF...IS SUGGESTING THAT THE PRECIPITATION WILL BE KNOCKING ON THE DOOR OF SOUTHEAST MINNESOTA. AS THE SYSTEM MOVES INTO THE REGION TOMORROW AFTERNOON...LIFT WILL BE MAXIMIZED AND THE PRECIPITATION WILL BECOME MORE WIDESPREAD AND INTENSE. MANY OF THE RAP FORECAST SOUNDINGS FOR TOMORROW MORNING SHOW THAT AS THE PROFILE BECOMES SATURATED...THE SURFACE/LOW LEVEL WET BULB TEMPERATURES SHOULD BE COLD ENOUGH TO PRODUCE ALL SNOW. SHOULD AIR TEMPERATURES STAY A BIT ON THE WARMER SIDE...IT COULD START AS RAIN...BUT AM LEANING MORE TOWARD THE IDEA THAT SNOW IS THE MORE LIKELY PRECIPITATION TYPE. IF THAT IS THE CASE...OUR FORECAST SNOW AMOUNTS WILL LIKELY NEED TO BE UPPED IN THE MORNING/AFTERNOON TOMORROW. THE RAP CAN TEND TO GO TOO LOW UNDER THE PRECIPITATION SHIELD...SO CONFIDENCE WAS NOT HIGH ENOUGH TO PUSH THE FORECAST THAT WAY...PARTICULARLY SINCE SURFACE TEMPERATURES ARE STILL IN THE MID TO UPPER 30S THROUGH MUCH OF THE AREA. THE OTHER QUESTION IS WITH ROAD TEMPERATURES AND HOW WARM THEY WILL BE TOMORROW. TODAY...UNDER MAINLY FULL SUN...THEY REACHED THE 50S/60S AND CURRENTLY ARE IN THE 40S. WITH HEAVY ENOUGH OF SNOW RATES IN THE AFTERNOON/EVENING TOMORROW...EXPECT THAT SNOW WILL BE ABLE TO ACCUMULATE ON THE ROADS AND CAUSE SOME SLICK CONDITIONS. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 349 PM CDT SAT MAR 21 2015 THE FOCUS FOR THIS PERIOD IS ON THE SYSTEM COMING THROUGH FOR SUNDAY AND SUNDAY NIGHT. WATER VAPOR SATELLITE SHOWS A COUPLE OF SHORT WAVE TROUGHS OVER THE PACIFIC NORTHWEST THIS AFTERNOON. THE FIRST WAS OVER THE ROCKIES OF NORTHERN IDAHO/NORTHWEST MONTANA WITH THE SECOND OVER WASHINGTON STATE. THE 21.12Z MODELS ALL HANDLE THESE WAVES SIMILARLY WITH THE LEAD WAVE OVER IDAHO/MONTANA THE MAIN PLAYER AS IT COMES ACROSS THE UPPER MIDWEST AND THE GREAT LAKES REGION WHILE THE SECOND WAVE GOES ACROSS SOUTHERN CANADA. THIS FIRST WAVE DOES NOT BECOME ALL THAT STRONG BUT ENOUGH TO PRODUCE SOME WEAK PV ADVECTION IN THE 500-300 MB LAYER SUNDAY AFTERNOON AND EVENING. THE UPPER LEVEL JET WILL ALSO BE ASSOCIATED WITH THIS WAVE WITH THE AREA COMING UNDER THE RIGHT ENTRANCE REGION AND ITS ASSOCIATED VERTICAL MOTIONS. IN THE LOW LEVELS...STILL EXPECTING A STRONG LOW LEVEL BAROCLINIC ZONE TO BE SET UP FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA. WEAK TO AT TIMES MODERATE FRONTOGENESIS WILL OCCUR OVER THE BAROCLINIC ZONE...ESPECIALLY IN THE 750-650 MB LAYER. THE ISENTROPIC UP GLIDE WILL BE ON THE ORDER OF 2 TO 4 UBAR/S ON THE 285K SURFACE SUNDAY EVENING. EXPECTING THAT ALL THIS FORCING WILL BE SUFFICIENT TO PRODUCE A BAND OF PRECIPITATION RIGHT ACROSS THE FORECAST AREA FROM NORTHWEST TO SOUTHEAST. WILL SHOW AN AREA OF 80 TO 100 PERCENT PRECIPITATION CHANCES STARTING ACROSS SOUTHEAST MINNESOTA BY LATE MORNING OR EARLY AFTERNOON AND SPREADING INTO WESTERN WISCONSIN BY LATE AFTERNOON INTO THE EVENING. PRECIPITATION TYPES REMAIN A CONCERN THROUGHOUT THE EVENT WITH THIS SYSTEM. EXPECTING THAT IT SHOULD INITIALLY START OUT AS SOME LIGHT RAIN. HOWEVER...WHEN THE BEST FORCING OCCURS...THE BUFKIT SOUNDINGS FROM BOTH THE NAM AND GFS SHOW STRONG LIFT THROUGH THE DENDRITIC GROWTH ZONE THAT SHOULD BE ABLE TO PRODUCE GOOD SNOW RATES AND CHANGE THE PRECIPITATION OVER TO ALL SNOW DESPITE THE BOUNDARY LAYER INITIALLY BEING ABOVE FREEZING. ALSO...THE LOW LEVEL FLOW WILL BE OUT OF THE EAST AND ALTHOUGH THIS WILL BE TRYING TO BRING SOME DRIER AIR...THIS DRIER AIR MAY HELP TO PUSH THE WET BULB ZERO TEMPERATURES DOWN AND AID IN THE TRANSITION TO ALL SNOW. THERE ALSO IS STILL SOME CONCERN ABOUT A LOSS OF ICE IN THE CLOUDS AS THE FORCING STARTS TO DIMINISH ON THE BACK SIDE OF THE PRECIPITATION BAND. WHILE THE MODELS HAVE BEEN CONSISTENT IN SHOWING THIS...THEY HAVE NOT BEEN CONSISTENT ON THE TIMING OF WHEN THE ICE COULD BE LOST WITH EACH MODEL RUN SHOWING THE ICE REMAINING LONGER. WILL STILL SHOW A CHANGE OVER TO FREEZING RAIN...BUT CONFIDENCE ON THIS CONTINUES TO BE LOW. WILL ISSUE A WINTER WEATHER ADVISORY FOCUSING ON THE BAND OF HEAVIER SNOW ACCUMULATIONS...GENERALLY IN THE 2 TO 4 INCH RANGE. STILL START THIS LATE SUNDAY MORNING ACROSS SOUTHEAST MINNESOTA INTO FAR WESTERN WISCONSIN AND RUN THIS THROUGH SUNDAY EVENING. WILL HAVE THE ADVISORY ALONG THE MISSISSIPPI RIVER INTO SOUTHWEST WISCONSIN FROM ABOUT THE MIDDLE OF SUNDAY AFTERNOON THROUGH SUNDAY NIGHT. THIS MAY HAVE TO BE EXPANDED LATER TO COVER THE ICING POTENTIAL...BUT CONFIDENCE ON THIS ASPECT OF THE FORECAST REMAINS TOO LOW TO ISSUE HEADLINES ON AT THIS TIME. .LONG TERM...(TUESDAY THROUGH SATURDAY) ISSUED AT 349 PM CDT SAT MAR 21 2015 ANOTHER SHORT WAVE COMING IN OVER THE PACIFIC NORTHWEST COAST WILL CROSS THE NORTHERN ROCKIES AND THEN IS EXPECTED TO DEEPEN OVER THE UPPER MIDWEST TUESDAY. THE MODELS ARE STILL BOUNCING AROUND WITH WHETHER THIS SYSTEM WILL COME THROUGH PHASED WITH ANOTHER NORTHERN STREAM SHORT WAVE TROUGH LIKE THE GFS SHOWS...OR WHETHER THE TWO SYSTEMS WILL REMAIN SEPARATE LIKE THE ECMWF AND GEM. EITHER WAY...ALL THE MODELS SHOW ONE AREA OF SURFACE LOW PRESSURE TRACKING ACROSS OR JUST NORTH OF THE FORECAST AREA WITH THE ECMWF AND GEM HAVING ANOTHER SURFACE LOW FARTHER NORTH UNDER THE OTHER SHORT WAVE TROUGH. EITHER OF THESE SOLUTIONS SHOULD ALLOW ENOUGH WARM AIR TO BE DRAWN IN FOR THIS SYSTEM TO PRIMARILY PRODUCE RAIN. THE TIMING LOOKS TO HAVE THE PRECIPITATION MOVING IN TUESDAY AFTERNOON WITH THE BEST CHANCES TUESDAY NIGHT...70 TO 80 PERCENT FOR THE ENTIRE AREA...AND THEN MOVES OUT WEDNESDAY AND WEDNESDAY NIGHT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1149 PM CDT SAT MAR 21 2015 THE MAIN FOCUS IS ON THE SNOW FOR TOMORROW WITH THE QUESTION BEING WHEN THE HEAVIEST SNOW BAND WILL MOVE THROUGH. CURRENTLY...IT APPEARS THAT THE SNOW WILL BEGIN AROUND 16Z AT RST AND 19Z AT LSE WITH IFR CONDITIONS LIKELY OCCURRING SOON AFTER IT BEGINS. THE HEAVIEST SNOWFALL LOOKS LIKE IT WILL COME IN THE AFTERNOON AND EVENING...SO HAVE KEPT THE VISIBILITY DOWN AROUND 3/4SM OVER THAT TIMEFRAME. THERE COULD BE SOME BRIEF PERIODS WHERE VISIBILITY DROPS LOWER THAN THAT...BUT CONFIDENCE IS NOT HIGH ENOUGH AT THIS POINT TO PUT THAT SORT OF DETAIL IN. REGARDLESS...IT LOOKS LIKE AN EXTENDED PERIOD OF IFR/LIFR CONDITIONS ONCE THE SNOW BEGINS TOMORROW. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY FROM 11 AM SUNDAY TO 1 AM CDT MONDAY FOR WIZ032-033. WINTER WEATHER ADVISORY FROM 3 PM SUNDAY TO 7 AM CDT MONDAY FOR WIZ041-053>055-061. MN...WINTER WEATHER ADVISORY FROM 11 AM SUNDAY TO 1 AM CDT MONDAY FOR MNZ079-086>088-094-095. WINTER WEATHER ADVISORY FROM 3 PM SUNDAY TO 7 AM CDT MONDAY FOR MNZ096. IA...WINTER WEATHER ADVISORY FROM 3 PM SUNDAY TO 7 AM CDT MONDAY FOR IAZ010-011. && $$ UPDATE...HALBACH SHORT TERM...04 LONG TERM...04 AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
825 AM MDT SUN MAR 22 2015 .UPDATE... ISSUED AT 821 AM MDT SUN MAR 22 2015 EARLY UPDATE THIS MORNING AS WAVE CLOUDS ARE FAIRLY THICK AND HAVE SPREAD ACROSS THE NORTHEAST PLAINS. PROBABLY ENOUGH MIXING THAT OUR HIGHS ARE ALRIGHT. REST OF FORECAST UNCHANGED. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 443 AM MDT SUN MAR 22 2015 UPPER LEVEL RIDGING WILL CONTINUE OVER COLORADO TODAY WITH TEMPERATURES WELL ABOVE SEASONAL NORMALS. THERE WILL BE A MODEST INCREASE IN MOISTURE ALOFT THROUGH THIS AFTERNOON AND EVENING AS THE UPPER RIDGE BEGINS WEAKENING AHEAD OF AN UPPER TROUGH MOVING OUT OF THE PACIFIC NORTHWEST. THE NAM AND GFS GENERATE SHOWER ACTIVITY OVER THE MOUNTAINS THIS AFTERNOON AND EVENING...BUT THE LATEST RUNS OF THE RAP KEEP CONDITIONS OVER COLORADO DRY THROUGH 03Z. WATER VAPOR IMAGERY SHOWS INCREASED MOISTURE OVER NEVADA AND UTAH BUT INFRARED SATELLITE PICTURES ONLY SHOW INCREASING CLOUDS OVER EASTERN UTAH AT THIS TIME. SINCE THE PREVIOUS FORECAST ALREADY HAD SOME LOW POPS IN THE MOUNTAINS THIS AFTERNOON AND EVENING...WILL STICK WITH THAT FOR NOW. WITH THE AIRMASS STARTING OUT SO WARM...WILL MENTION THE PRECIPITATION BEGINNING AS RAIN OR A MIX OF RAIN AND SNOW. POPS WILL MAX OUT IN THE 40-50 PERCENT RANGE DURING THE LATTER HALF OF THE AFTERNOON. WINDS ACROSS NORTHEAST COLORADO TODAY MAY BE AFFECTED BY A WEAK SURFACE FRONT MOVING OUT OF WYOMING. CURRENTLY...ANY PRESSURE RISES OVER WYOMING ARE WEAK...BUT AS THE LEE TROUGH THAT HAS BEEN IN PLACE OVER NORTHEAST COLORADO MOVES AWAY FROM THE FOOTHILLS WINDS SHOULD BECOME NORTHERLY LATE IN THE MORNING AND NORTHEASTERLY LATER IN THE AFTERNOON. THE COMBINATION OF WEAK NORTH WINDS AND GRADUALLY INCREASING CLOUDS SHOULD KEEP HIGH TEMPERATURES AT AROUND THE SAME NUMBERS THEY WERE YESTERDAY AFTERNOON. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 443 AM MDT SUN MAR 22 2015 THE FLOW ALOFT WILL BECOME MORE WSW ON MON AHEAD OF AN UPPER LVL THAT WILL MOVE QUICKLY ACROSS WY AND NRN CO MON NIGHT. AT THE SFC LOW PRES WILL INTENSIFY FM ERN WY INTO ERN CO WITH INCREASING SSE LOW LVL FLOW ACROSS THE PLAINS. CROSS-SECTIONS SHOW MOISTURE WILL INCREASE IN THE MTNS BY LATE AFTN SO WILL KEEP IN A CHC OF SHOWERS MAINLY NORTH OF I-70. ACROSS THE PLAINS IT WILL BE MAINLY DRY EXCEPT FOR A SLIGHT CHC OF CONVECTION NR THE WY-CO BORDER. AS FOR HIGHS WILL KEEP READINGS IN THE UPPER 60S TO LOWER 70S ACROSS NERN CO. FOR MON NIGHT INTO EARLY TUE A QUICK MOVING UPPER LEVEL TROUGH WILL AFFECT THE AREA WITH A DECENT SHOT OF MID LVL ASCENT ALONG WITH RATHER STEEP LAPSE RATES. THUS SHOULD SEE SNOW INCREASE IN THE MTNS MON EVENING BUT THEN DECREASE BY TUE MORNING. SOME AREAS COULD GET CLOSE TO LOWER END ADVISORY AMOUNTS NORTH OF I-70. AT LOWER ELEVATIONS WITH STEEP LAPSE RATES AND FAVORABLE MID LVL ASCENT THERE WILL BE A CHC OF SHOWERS AND A FEW TSTMS MON NIGHT ESPECIALLY NR THE WY-NE BORDER WITH LOWER CHANCES FURTHER SOUTH. ON TUE THE UPPER LEVEL TROUGH WILL EXIT THE AREA TUE MORNING WITH STG DOWNWARD DESCENT THRU THE AFTN HOURS. ALTHOUGH OROGRAPHICS WILL REMAIN FAVORABLE IN THE MTNS MOISTURE DEPTH WILL BE MARGINAL THRU THE AFTN SO ANY ADDITIONAL ACCUMULATIONS WILL BE ON THE LIGHT SIDE. OVER NERN CO WITH STG DOWNWARD FORCING IN PLACE DO NOT EXPECT ANY PCPN ALTHOUGH THERE COULD BE A FEW LINGERING SHOWERS OVER THE FAR NERN CORNER IN THE MORNING. MEANWHILE WITH DECENT LOW LVL GRADIENT IN PLACE AND DOWNWARD DESCENT EXPECT FAIRLY STG WINDS FM THE NRN FOOTHILLS ACROSS THE PLAINS. WINDS COULD GET CLOSE TO WARNING CRITERIA FOR A FEW HOURS ESPECIALLY CLOSER TO THE WY-NE BORDER. ALSO CONSIDERING HOW DRY IT HAS BEEN OVER PORTIONS OF THE PLAINS BLOWING DUST WILL CERTAINLY BE POSSIBLE AS WELL. AS FOR HIGHS READINGS WILL COOL BACK INTO THE LOWER TO MID 60S OVER NERN CO. FOR TUE NIGHT AND WED THE FLOW ALOFT WILL BECOME MORE NWLY WITH A DISTURBANCE POSSIBLY AFFECTING THE AREA ON WED. MOISTURE WILL INCREASE IN THE MTNS WITH FAVORABLE OROGRAPHICS AND LAPSE RATES SO SHOULD SEE A GOOD CHC OF SNOW. AT LOWER ELEVATIONS A CDFNT WILL MOVE ACROSS NERN CO LATE TUE NIGHT INTO WED MORNING WITH NLY LOW LVL FLOW. AS THE DISTURBANCE MOVES ACROSS DURING THE DAY THERE MAY BE AT LEAST A SLIGHT CHC OF LIGHT PCPN BEHIND THE FNT SO WILL KEEP IN LOW POPS OVER NERN CO. AS FOR HIGHS THE ECWMF HAS READINGS IN THE 40S OVER NERN CO WHILE THE GFS HAS TEMPS IN THE 50S. FOR NOW WILL KEEP HIGHS IN THE LOWER TO MID 50S. FOR WED NIGHT INTO THU NWLY FLOW ALOFT WILL REMAIN OVER THE AREA. THE ECMWF AND GFS STILL DISAGREE AS TO HOW MUCH MOISTURE IS EMBEDDED IN THE FLOW AND WHETHER ANOTHER SURGE OF COOLER AIR WILL AFFECT NERN CO. THE ECMWF CONTINUES TO SHOW VERY LITTLE MOISTURE ON THU AND DOES NOT HAVE ANOTHER FNT AFFECTING THE PLAINS. AS A RESULT IT HAS NO PCPN AND SHOWS WARMER TEMPS. MEANWHILE THE GFS HAS SOME MOISTURE EMBEDDED IN THE FLOW AND SHOWS ANOTHER FNT MOVING ACROSS NERN CO DURING THE DAY. THIS LEADS TO A CHC OF SNOW IN THE MTNS AND POSSIBLY SOME LIGHT PCPN OVER NERN CO. WILL CONTINUE TO KEEP POPS ON THE LOW SIDE ON THU SINCE THERE IS NO AGREEMENT BETWEEN THE TWO MODELS. AS FAR AS HIGHS WILL KEEP READINGS IN THE 50S OVER NERN CO. BY FRI AND SAT BOTH THE ECMWF AND GFS SHOW DRY NWLY FLOW ALOFT OVER THE AREA WITH NO PCPN. HIGHS WILL GRADUALLY RISE BOTH DAYS WITH 70S POSSIBLY BY SATURDAY OVER NERN CO. && .AVIATION...(FOR THE TAFS THROUGH 18Z MONDAY MORNING) ISSUED AT 821 AM MDT SUN MAR 22 2015 VFR THROUGH TONIGHT. STILL EXPECTING A SHIFT TO NORTHERLY WINDS AROUND 16Z. ISOLATED SHOWERS IN THE LATE AFTERNOON AND EVENING SHOULD HAVE LITTLE OR NO IMPACT AS CEILINGS WILL REMAIN HIGH. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GIMMESTAD SHORT TERM...DANKERS LONG TERM...RPK AVIATION...GIMMESTAD
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
443 AM MDT SUN MAR 22 2015 .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 443 AM MDT SUN MAR 22 2015 UPPER LEVEL RIDGING WILL CONTINUE OVER COLORADO TODAY WITH TEMPERATURES WELL ABOVE SEASONAL NORMALS. THERE WILL BE A MODEST INCREASE IN MOISTURE ALOFT THROUGH THIS AFTERNOON AND EVENING AS THE UPPER RIDGE BEGINS WEAKENING AHEAD OF AN UPPER TROUGH MOVING OUT OF THE PACIFIC NORTHWEST. THE NAM AND GFS GENERATE SHOWER ACTIVITY OVER THE MOUNTAINS THIS AFTERNOON AND EVENING...BUT THE LATEST RUNS OF THE RAP KEEP CONDITIONS OVER COLORADO DRY THROUGH 03Z. WATER VAPOR IMAGERY SHOWS INCREASED MOISTURE OVER NEVADA AND UTAH BUT INFRARED SATELLITE PICTURES ONLY SHOW INCREASING CLOUDS OVER EASTERN UTAH AT THIS TIME. SINCE THE PREVIOUS FORECAST ALREADY HAD SOME LOW POPS IN THE MOUNTAINS THIS AFTERNOON AND EVENING...WILL STICK WITH THAT FOR NOW. WITH THE AIRMASS STARTING OUT SO WARM...WILL MENTION THE PRECIPITATION BEGINNING AS RAIN OR A MIX OF RAIN AND SNOW. POPS WILL MAX OUT IN THE 40-50 PERCENT RANGE DURING THE LATTER HALF OF THE AFTERNOON. WINDS ACROSS NORTHEAST COLORADO TODAY MAY BE AFFECTED BY A WEAK SURFACE FRONT MOVING OUT OF WYOMING. CURRENTLY...ANY PRESSURE RISES OVER WYOMING ARE WEAK...BUT AS THE LEE TROUGH THAT HAS BEEN IN PLACE OVER NORTHEAST COLORADO MOVES AWAY FROM THE FOOTHILLS WINDS SHOULD BECOME NORTHERLY LATE IN THE MORNING AND NORTHEASTERLY LATER IN THE AFTERNOON. THE COMBINATION OF WEAK NORTH WINDS AND GRADUALLY INCREASING CLOUDS SHOULD KEEP HIGH TEMPERATURES AT AROUND THE SAME NUMBERS THEY WERE YESTERDAY AFTERNOON. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 443 AM MDT SUN MAR 22 2015 THE FLOW ALOFT WILL BECOME MORE WSW ON MON AHEAD OF AN UPPER LVL THAT WILL MOVE QUICKLY ACROSS WY AND NRN CO MON NIGHT. AT THE SFC LOW PRES WILL INTENSIFY FM ERN WY INTO ERN CO WITH INCREASING SSE LOW LVL FLOW ACROSS THE PLAINS. CROSS-SECTIONS SHOW MOISTURE WILL INCREASE IN THE MTNS BY LATE AFTN SO WILL KEEP IN A CHC OF SHOWERS MAINLY NORTH OF I-70. ACROSS THE PLAINS IT WILL BE MAINLY DRY EXCEPT FOR A SLIGHT CHC OF CONVECTION NR THE WY-CO BORDER. AS FOR HIGHS WILL KEEP READINGS IN THE UPPER 60S TO LOWER 70S ACROSS NERN CO. FOR MON NIGHT INTO EARLY TUE A QUICK MOVING UPPER LEVEL TROUGH WILL AFFECT THE AREA WITH A DECENT SHOT OF MID LVL ASCENT ALONG WITH RATHER STEEP LAPSE RATES. THUS SHOULD SEE SNOW INCREASE IN THE MTNS MON EVENING BUT THEN DECREASE BY TUE MORNING. SOME AREAS COULD GET CLOSE TO LOWER END ADVISORY AMOUNTS NORTH OF I-70. AT LOWER ELEVATIONS WITH STEEP LAPSE RATES AND FAVORABLE MID LVL ASCENT THERE WILL BE A CHC OF SHOWERS AND A FEW TSTMS MON NIGHT ESPECIALLY NR THE WY-NE BORDER WITH LOWER CHANCES FURTHER SOUTH. ON TUE THE UPPER LEVEL TROUGH WILL EXIT THE AREA TUE MORNING WITH STG DOWNWARD DESCENT THRU THE AFTN HOURS. ALTHOUGH OROGRAPHICS WILL REMAIN FAVORABLE IN THE MTNS MOISTURE DEPTH WILL BE MARGINAL THRU THE AFTN SO ANY ADDITIONAL ACCUMULATIONS WILL BE ON THE LIGHT SIDE. OVER NERN CO WITH STG DOWNWARD FORCING IN PLACE DO NOT EXPECT ANY PCPN ALTHOUGH THERE COULD BE A FEW LINGERING SHOWERS OVER THE FAR NERN CORNER IN THE MORNING. MEANWHILE WITH DECENT LOW LVL GRADIENT IN PLACE AND DOWNWARD DESCENT EXPECT FAIRLY STG WINDS FM THE NRN FOOTHILLS ACROSS THE PLAINS. WINDS COULD GET CLOSE TO WARNING CRITERIA FOR A FEW HOURS ESPECIALLY CLOSER TO THE WY-NE BORDER. ALSO CONSIDERING HOW DRY IT HAS BEEN OVER PORTIONS OF THE PLAINS BLOWING DUST WILL CERTAINLY BE POSSIBLE AS WELL. AS FOR HIGHS READINGS WILL COOL BACK INTO THE LOWER TO MID 60S OVER NERN CO. FOR TUE NIGHT AND WED THE FLOW ALOFT WILL BECOME MORE NWLY WITH A DISTURBANCE POSSIBLY AFFECTING THE AREA ON WED. MOISTURE WILL INCREASE IN THE MTNS WITH FAVORABLE OROGRAPHICS AND LAPSE RATES SO SHOULD SEE A GOOD CHC OF SNOW. AT LOWER ELEVATIONS A CDFNT WILL MOVE ACROSS NERN CO LATE TUE NIGHT INTO WED MORNING WITH NLY LOW LVL FLOW. AS THE DISTURBANCE MOVES ACROSS DURING THE DAY THERE MAY BE AT LEAST A SLIGHT CHC OF LIGHT PCPN BEHIND THE FNT SO WILL KEEP IN LOW POPS OVER NERN CO. AS FOR HIGHS THE ECWMF HAS READINGS IN THE 40S OVER NERN CO WHILE THE GFS HAS TEMPS IN THE 50S. FOR NOW WILL KEEP HIGHS IN THE LOWER TO MID 50S. FOR WED NIGHT INTO THU NWLY FLOW ALOFT WILL REMAIN OVER THE AREA. THE ECMWF AND GFS STILL DISAGREE AS TO HOW MUCH MOISTURE IS EMBEDDED IN THE FLOW AND WHETHER ANOTHER SURGE OF COOLER AIR WILL AFFECT NERN CO. THE ECMWF CONTINUES TO SHOW VERY LITTLE MOISTURE ON THU AND DOES NOT HAVE ANOTHER FNT AFFECTING THE PLAINS. AS A RESULT IT HAS NO PCPN AND SHOWS WARMER TEMPS. MEANWHILE THE GFS HAS SOME MOISTURE EMBEDDED IN THE FLOW AND SHOWS ANOTHER FNT MOVING ACROSS NERN CO DURING THE DAY. THIS LEADS TO A CHC OF SNOW IN THE MTNS AND POSSIBLY SOME LIGHT PCPN OVER NERN CO. WILL CONTINUE TO KEEP POPS ON THE LOW SIDE ON THU SINCE THERE IS NO AGREEMENT BETWEEN THE TWO MODELS. AS FAR AS HIGHS WILL KEEP READINGS IN THE 50S OVER NERN CO. BY FRI AND SAT BOTH THE ECMWF AND GFS SHOW DRY NWLY FLOW ALOFT OVER THE AREA WITH NO PCPN. HIGHS WILL GRADUALLY RISE BOTH DAYS WITH 70S POSSIBLY BY SATURDAY OVER NERN CO. && .AVIATION...(FOR THE TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 443 AM MDT SUN MAR 22 2015 NO AVIATION IMPACTS FROM WEATHER TODAY AND TONIGHT. HIGH CLOUDS WILL BE GRADUALLY INCREASING THIS AFTERNOON AND OVERNIGHT BUT CEILINGS SHOULD REMAIN ABOVE 8000 FEET AGL. SOUTHERLY WINDS THIS MORNING ARE EXPECTED TO SWITCH TO NORTHERLY LATE IN THE MORNING THEN NORTHEAST TO EASTERLY LATE IN THE AFTERNOON AND EVENING. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...DANKERS LONG TERM...RPK AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
650 AM EDT SUN MAR 22 2015 .SYNOPSIS... A LOW PRESSURE SYSTEM WILL DEVELOP ALONG THE GULF COAST AND BRING RAIN BACK TO THE AREA TODAY THROUGH MONDAY. COOLER TEMPERATURES WILL OCCUR. SURFACE RIDGE TO THE NORTH AND A WEAK TROUGH ALONG THE CAROLINA COAST WILL PERSIST THROUGH MIDWEEK. && .NEAR TERM /THROUGH TONIGHT/... WEAK SURFACE LOW DEVELOPING IN THE NORTHWEST GULF OF MEXICO. RADAR AT 0730Z INDICATING LIGHT RAIN MOVING ACROSS THE SAVANNAH RIVER INTO THE MIDLANDS FROM CENTRAL GEORGIA. LATEST HRRR RADAR SIMULATION APPEARS TO HAVE A HANDLE ON PRECIPITATION TREND. HRRR MODEL SPREADS LIGHT PRECIPITATION TO THE NORTH DURING THE MORNING AS MOISTURE FLUX/ISENTROPIC LIFT INCREASES. BASED ON RADAR/MODEL CONSENSUS...RAISED POPS ACROSS THE REGION. THE UPPER LEVEL TROUGH OVER THE SOUTHERN PLAINS WILL CONTINUE TO TRACK TO THE NORTHEAST TODAY...ACROSS THE MISSISSIPPI VALLEY THIS EVENING. INCREASING ISENTROPIC LIFT THIS AFTERNOON AND THIS EVENING. PRECIPITABLE WATER ABOVE CLIMATOLOGICAL MEAN WITH HIGHEST VALUES IN THE CSRA...AROUND 1.3 INCHES. AS UPPER LEVEL LOW MOVES OVER THE REGION TONIGHT...EXPECT STRONGEST LIFT DURING THIS TIME AND WILL MENTION POSSIBLE MODERATE RAIN MAINLY SOUTHERN AREAS. A TIGHT PRECIPITATION GRADIENT EXPECTED WITH STRONGEST 850MB CONVERGENCE ACROSS SOUTHERN MIDLANDS. LIGHTER AMOUNTS ACROSS NORTH MIDLANDS. WITH RAIN AND EXTENSIVE CLOUDS TEMPERATURES EXPECTED TO RISE A FEW DEGREES FROM MORNING LOWS...SO LOW TO MID 60S APPEARS ON TRACK. MOS CONSENSUS FOR MINIMUM TEMPERATURES HAS BEEN CONSISTENT AND APPEARS ACCEPTED. && .SHORT TERM /MONDAY THROUGH TUESDAY/... COLD AIR DAMMING/WEDGE APPEARS LIKELY MONDAY WITH WEAK ISENTROPIC LIFT/MOISTURE FLUX CONTINUING THROUGH AT LEAST 18Z. LIGHT PRECIPITATION OR DRIZZLE MAY CONTINUE THROUGH AFTERNOON. RAISED POPS ALL AREAS FROM PREVIOUS FORECAST. PREFER COOLER MAV GUIDANCE WHICH IS IN LINE WITH THE SREF AND LOCAL WEDGE GUIDANCE...SO LOW TO MID 50S WITH TEMPERATURES LIKELY FALLING THROUGH THE AFTERNOON AS RIDGE STRENGTHENS TO THE NORTH. WEAK ONSHORE FLOW MAY CONTINUE THROUGH TUESDAY...SO INCREASED CLOUDS WITH MODEST WARMING. SHOWERS APPEAR POSSIBLE MAINLY CLOSER TO THE COAST SO FOR NOW WILL LEAVE POPS BELOW 15 PERCENT. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... GENERAL AGREEMENT CONTINUES IN THE EXTENDED FORECAST PERIOD WITH THE OVERALL PATTERN...THOUGH THERE IS UNCERTAINTY LATE IN THE FORECAST DUE TO TIMING AND STRENGTH DIFFERENCES ASSOCIATED WITH A DEEP UPPER TROUGH DIGGING ACROSS THE MIDDLE PART OF THE COUNTRY. FOR THE MOST PART...USED A BLEND OF GFS/PREVIOUS ECMWF/HPC GUIDANCE. THERE IS UNCERTAINTY WITH POSSIBLE RAIN CHANCES WEDNESDAY AS A WEAK INVERTED TROUGH MAY DEVELOP ALONG THE COAST WITH THE SURFACE HIGH RETREATING IN ADVANCE OF THE NEXT STORM SYSTEM...ALTHOUGH THE COOL WEDGE MAY BE STRONGER THAN FORECAST. A DIGGING TROUGH ACROSS THE NORTHERN HALF OF THE COUNTRY THURSDAY INTO FRIDAY WILL RESULT IN INCREASING MOISTURE IN DEVELOPING SOUTHWESTERLY FLOW AHEAD OF AN APPROACHING COLD FRONT. FORECAST INSTABILITY OF LIFTED INDEX VALUES AROUND MINUS 2 THURSDAY AFTERNOON WOULD SUPPORT AN ISOLATED THUNDERSTORM THREAT. RAIN CHANCES CONTINUE INTO FRIDAY DUE TO TIMING ISSUES BETWEEN THE MODELS. AT THIS TIME SATURDAY APPEARS DRY WITH HIGH PRESSURE BUILDING IN FROM THE WEST. TEMPERATURES GENERALLY BELOW NORMAL TUESDAY...AOA NORMAL WEDNESDAY THROUGH FRIDAY...AND BELOW NORMAL SATURDAY. && .AVIATION /10Z SUNDAY THROUGH THURSDAY/... HIGH CONFIDENCE IN RESTRICTIONS BEGINNING OVER THE NEXT COUPLE OF HOURS AND CONTINUING THROUGH THE END OF THE PERIOD. RAIN CONTINUES TO SPREAD INTO THE TAF SITES WITH RESTRICTIONS EXPECTED TO ARRIVE IN THE NEXT COUPLE OF HOURS. WSR-88D NETWORK SHOWS LIGHT RAIN AROUND THE TAF SITES WITH HEAVIER RAIN ACROSS CENTRAL AND SOUTHERN GA WHICH WILL MOVE INTO THE AREA LATER TODAY. CONDITIONS WILL REMAIN LOW END MVFR TO IFR FROM THE LATE MORNING THROUGH TONIGHT. LIFR CONDITIONS POSSIBLE AFTER 23/06Z...HOWEVER CONFIDENCE TOO LOW TO INCLUDE IN TAFS ATTM. WINDS THROUGH THE PERIOD WILL BE NORTHEASTERLY AT 7 KNOTS OR LESS. EXTENDED AVIATION OUTLOOK...HIGH CONFIDENCE IN CIG/VSBY RESTRICTIONS CONTINUING THROUGH MONDAY NIGHT IN WEDGE CONDITIONS. THERE MAY BE ANOTHER CHANCE FOR RAIN AND ASSOCIATED RESTRICTIONS TUESDAY NIGHT THROUGH THURSDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1103 AM CDT SUN MAR 22 2015 .UPDATE... 1025 AM CDT ONLY SMALL CHANGES MADE TO THE FORECAST FOR THIS AFTERNOON. HAVE ADDED THE MENTION OF SOME FLURRIES OR POSSIBLY SPRINKLES THIS AFTERNOON IN FAR NORTHERN ILLINOIS...BUT AS FOR THIS EVENING CONTINUE TO DELAY MENTION OF MEASURABLE PRECIPITATION CHANCES. A CANOPY OF MID-LEVEL CLOUDS FROM SOUTHERN/CENTRAL MN THROUGH FAR NORTHERN IL AND SOUTHERN LAKE MI HIGHLIGHTS A WEAK ZONE OF MID-LEVEL FORCING ALONG A MODEST THERMAL GRADIENT. THE NATURE OF SOME OF THE SOUTHERN EDGE CLOUDS AS WELL AS 35-40DBZ ECHOES ON COMPOSITE RADAR NEAR THE IA/MN BORDER INDICATE THE PRESENCE OF AT LEAST WEAK INSTABILITY ALOFT AND LIKELY THE RESULT OF A SUBTLE MID-LEVEL PERTURBATION PER SATELLITE AND RAP ANALYSIS. IT IS POSSIBLE AS THIS CORRIDOR OF SHOWERY-TYPE ECHOES BRINGS SOME SPRINKLES OR FLURRIES TO FAR NORTHERN IL EARLY TO MID AFTERNOON...SO THAT IS WHY THE EARLIER MENTION IN THE FORECAST. OVERALL THOUGH...THE DRIER SYNOPTIC AIR AND DRY 925-850MB TRAJECTORIES WILL LIKELY PREVENT ANY NOTEWORTHY PRECIP INTO THIS EVE AND POSSIBLY THROUGH EARLY OVERNIGHT UNTIL STRONGER FORCING WITH THE MAIN UPPER SHORT WAVE APPROACH. THE CHALLENGE WITH THIS UPCOMING SNOW EVENT LOOKS TO BE IF THERE WILL BE A CORRIDOR/BAND OF MODERATE SNOWFALL RATES DURING THE DAYBREAK THROUGH MID-MORNING HOURS ON MONDAY...WHICH SOME HIGH RESOLUTION MODELS INCLUDING THE 12Z NAM INDICATE AND THIS MAKES SENSE SOMEWHERE IN THE REGION WITH THIS TYPE OF SYSTEM. IT IS JUST PLACEMENT AND DURATION IS THE CHALLENGE. THESE MORE APPRECIABLE RATES EVEN IF TEMPORARY WOULD HAVE AT LEAST A SLIGHTLY GREATER IMPACT DUE TO OVERCOMING THE NOW WARMER PAVEMENT AND GROUND TEMPERATURES. WILL CONTINUE TO LOOK AT GUIDANCE AND REFINE THE FORECAST WITH MORE TEMPORAL AND SPATIAL RESOLUTION FOR MONDAY MORNING AND IF NEEDED ISSUE SOME FORM OF STATEMENT TO FURTHER HIGHLIGHT. MTF && .SHORT TERM... 235 AM CDT THROUGH MONDAY... MAIN CONCERN IN THE SHORT TERM WILL REVOLVE AROUND TIMING OF A DEVELOPING MID-LVL SHORTWAVE FOR LATE TONIGHT INTO MONDAY MORNING...WHICH WILL LIKELY BRING SOME LIGHT ACCUMULATING SNOWFALL TO MAINLY NORTHERN IL. PRIOR TO THE ARRIVAL OF THIS SYSTEM...EARLY THIS MORNING THE SURFACE ANTI-CYCLONIC FEATURE REMAINED CENTERED OVER THE GREAT LAKES REGION. THIS FEATURE WAS SENDING MUCH DRIER AIR SOUTH ACROSS THE WESTERN GREAT LAKES WITH NUMEROUS LOCATIONS IN WISC SEEING DEW PTS IN THE SINGLE DIGITS TO LOW TEENS...ALTHOUGH ACROSS NORTHERN IL DEW PTS REMAINED IN THE LOW/MID 20S. THIS WAS A RESULT OF THE NORTHEAST WINDS ALLOWING THE MARINE ENVIRONMENT TO BLEED INLAND. GUIDANCE CONTINUES TO SUGGEST THE SFC RIDGE WILL REMAIN ORIENTED ACROSS THE UPPER MIDWEST/GREAT LAKES STRETCHING NORTH INTO CENTRAL ONTARIO THROUGH TONIGHT AND INTO MONDAY. THIS WILL MAINTAIN A COOL/DRY NORTHEAST TO EAST LLVL FLOW ACROSS THE FORECAST AREA. IR IMAGERY INDICATES A THIN CIRRUS SHIELD OVERHEAD...BUT WILL STEADILY THICKEN AS THE AFTN/EVE PROGRESSES. HIGHS TODAY WILL STRUGGLE TO WARM BEYOND THE LOW/MID 40S...WITH A FEW AREAS IN THE FAR SOUTHWEST NEARING 50. AREAS ADJACENT TO LAKE MICHIGAN WILL BE UNDER THE INFLUENCE OF A COLD MARINE ENVIRONMENT...LIKELY HOLDING TEMPS IN THE UPR 30S WITHIN THE FIRST FEW MILES OF LAND AWAY FROM THE LAKE. THE FOR TONIGHT...GUIDANCE HAS LOCKED IN THE DRY AIR WHICH APPEARS TO BE DELAYING THE MOISTENING LOW/MID LVLS UNTIL LATE TONIGHT. USING A T-LAG DISPLAY OF SOUNDINGS WOULD SUGGEST THE TREND HAS BEEN TO PUSH BACK PRECIP UNTIL ARND 6Z BUT THAT TOO COULD BE A FEW HOURS EARLY. HAVE HELD ONTO DRY CONDS LONGER WITH SLT CHC POPS ARRIVING ARND 6Z...THEN STEADILY INCREASING TO LIKELY ARND 9Z THRU ABOUT 12- 14Z. A BAROCLINIC ZONE WILL BE ORIENTED FROM SOUTHEAST IOWA EAST THROUGH CENTRAL IL INTO CENTRAL IN BY EARLY MON AFTN. THE LOW WILL LIKELY FOLLO THIS ORIENTATION AS IT NEARS THE REGION LATE TONIGHT. THERE CONTINUES TO BE SOME DEGREE OF UNCERTAINTY ON THE DURATION OF THE SNOW...HOWEVER DYNAMICALLY SPEAKING THE FORCING CRANKS UP LATE TONIGHT WITH STEEPING MID-LVL LAPSE RATES AND A TIGHTENING GRADIENT ALONG THE BAROCLINIC ZONE. WITH STRONG ASCENT ALONG THE LEADING EDGE...QUICK MOISTENING OF THE LLVLS SHUD OCCUR AND MAY ALLOW FOR A FEW HRS OF MODERATE SNOW BETWEEN 10-14Z...BEFORE THE PROFILE BEGINS TO WARM AND LIFT BEGINS TO DECREASE BY 15-17Z MON. SNOW ACCUMS ARE POSSIBLE AND TIMING APPEARS TO BE JUST PRIOR TO RUSH-HOUR MON MORNING...AND ENDING SHORTLY AFTER. CURRENT INDICATIONS ARE FOR ARND 1 INCH CLOSER TO CHICAGO...AND POSSIBLY UP TO 2 INCHES IN A FEW AREAS ALONG AND WEST OF A DIXON TO CRYSTAL LAKE LINE. THICK SOLAR SHIELDING WILL KEEP TEMPS WELL BELOW SEASONAL CONDS MON...WITH HIGHS MAINLY IN THE MID/UPR 30S. PRECIP SHUD BE ENDING BY EARLY AFTN MON. BEACHLER && .LONG TERM... 354 AM CDT MONDAY NIGHT THROUGH SATURDAY... ATTENTION DURING THE LONG TERM PERIOD IS MAINLY FOCUSED ON THE POTENTIAL FOR A GOOD STORM SYSTEM TO IMPACT THE REGION LATE TUESDAY THROUGH WEDNESDAY. MODEL GUIDANCE CONTINUES IN DECENT AGREEMENT WITH THE EVOLUTION OF A STORM SYSTEM ACROSS THE CENTRAL PORTION OF THE COUNTRY BY MID WEEK. UPPER LEVEL ENERGY EMANATING FROM THE NORTHEASTERN PACIFIC IS EXPECTED TO SHIFT EASTWARD ONSHORE ACROSS THE PACIFIC NORTHWEST BY MONDAY...THEN OVER THE ROCKIES BY TUESDAY MORNING. THIS SHOULD SPAWN SURFACE LOW PRESSURE OVER THE PLAINS DURING THE DAY TUESDAY. MODEL GUIDANCE IS ALSO INSISTENT THAT THE MAIN MID/UPPER LEVEL SHORT WAVE WILL BECOME NEGATIVELY TILTED AS IT MOVES OVER THE MID MISSOURI VALLEY LATE TUESDAY INTO TUESDAY NIGHT. AS SUCH...THIS IS SHAPING UP TO POSSIBLY BE A GOOD DYNAMIC SYSTEM CAPABLE OF PRODUCING THUNDERSTORMS OVER THE AREA...ESPECIALLY TUESDAY NIGHT...FOLLOWED BY SOME STRONG SYNOPIC WINDS INTO WEDNESDAY. IT CURRENTLY APPEARS THAT MOST OF NORTHERN ILLINOIS/NORTHWESTERN INDIANA MAY END UP STAYING DRY FOR MOST OF THE DAY TUESDAY AS MOST OF THE SHOWERS LOOK TO REMAIN FOCUSED DOWN STATE IN CLOSER PROXIMITY TO THE WARM FRONTAL BOUNDARY. FOR THIS REASON I HAVE CUT BACK ON POPS ACROSS NORTHERN ILLINOIS DURING THE DAY TUESDAY. THE BEST POTENTIAL FOR SHOWERS AND THUNDERSTORMS FOR THE AREA LOOKS TO BE TUESDAY EVENING AND INTO THE PREDAWN HOURS OF OF WEDNESDAY MORNING. THIS IS THE PERIOD WHEN THE MAIN MID LEVEL NEGATIVELY TILTED SYSTEM BEGINS TO SHIFT OVER NORTHERN ILLINOIS. AS THIS OCCURS...THE SURFACE LOW WILL ACCELERATE NORTHEASTWARD AND DEEPEN INTO WEDNESDAY. THIS WILL RAPIDLY SHIFT THE WARM FRONT AND BETTER MOISTURE FROM DOWNSTATE ILLINOIS RIGHT ACROSS THE AREA BY TUESDAY EVENING. THINGS LOOK TO DRY OUT IN A HURRY BY EARLY WEDNESDAY FOLLOWING THE PASSAGE OF THE MID LEVEL SYSTEM AND DRY PUNCH. THE MAIN WEATHER ISSUE ON WEDNESDAY WILL BE THE POTENTIAL FOR STRONG WEST- SOUTHWESTERLY WINDS. IT CURRENTLY APPEARS THAT WINDS COULD GUST TO AROUND 40 TO 45 MPH ON WEDNESDAY AS THE COMBINATION OF MUCH DRIER AIR...GOOD LARGE SCALE DECENT IN THE WAKE OF THE UPPER LEVEL SYSTEM AND SOME DECENT SURFACE PRESSURE RISES...COULD LEAD TO EFFICIENT ATMOSPHERIC MIXING OF STRONG WINDS OFF THE SURFACE. MID/UPPER LEVEL HEIGHTS ARE EXPECTED TO BUILD ACROSS WESTERN NORTH AMERICA BY MID WEEK...AND THIS WILL ULTIMATELY SET UP TROUGHING OVER THE EASTERN CONUS...FEATURING NORTHWEST FLOW ALOFT OVER THE WESTERN GREAT LAKES REGION. THEREFORE...MILD CONDITIONS TUESDAY NIGHT AND WEDNESDAY WILL TRANSITION TO COLDER WEATHER AGAIN BY THURSDAY AS THIS PATTERN ALLOWS MUCH COLDER AIR TO SPILL IN ACROSS THE EASTERN CONUS FOR THE LATER HALF OF THE WEEK. HIGHS WILL LIKELY END UP 10 TO 15 DEGREES BELOW AVERAGE FOR A FEW DAYS AT THE END OF THE PERIOD (30S TO LOW 40S). IT ALSO APPEARS THAT THERE COULD BE SOME PERIODIC EPISODES OF SNOW AND RAIN SHOWERS AS ADDITIONAL MID LEVEL DISTURBANCES SHIFT SOUTHEASTWARD ACROSS THE REGION. KJB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * NORTHEAST WINDS 10 TO 15 KT THRU THIS EVENING...WITH HIGHER GUSTS POSSIBLE. * SNOW DEVELOPING AROUND DAYBREAK MONDAY MORNING WITH MVFR CIGS/VIS...IFR POSSIBLE. CMS //DISCUSSION...UPDATED 12Z... HIGH PRESSURE REMAINS CENTERED TO THE NORTH OF THE REGION...AND WILL CONTINUE TO ALLOW NORTHEAST TO EAST WINDS THRU THE DURATION OF THE CURRENT TAF. WITH THE LACK OF MIXING OVERNIGHT...THE WIND SPEEDS HAVE FALLEN OFF SLIGHTLY. EXPECT SHORTLY AFTER DAYBREAK THE WIND SPEEDS TO PICK BACK UP AND GUSTS TO 15KT WILL BE FREQUENT. THE LOW/MID LVLS IN THE ATMOSPHERE REMAIN VERY DRY...WHICH WILL ALLOW MINIMAL CLOUDS IN THE LOWER LEVELS. A CIRRUS SHIELD WILL STEADILY THICKEN AND BEGIN TO LOWER...ALTHOUGH EXPECT VFR CONDS TO PREVAIL THRU AT LEAST 00Z AND POSSIBLY BEYOND 6Z MON TONIGHT. THE FOCUS THEN TURNS TOWARDS THE DEVELOPING LOW PRESSURE SYSTEM ACROSS THE CENTRAL PLAINS...THAT GUIDANCE HAS CONTINUED TO SUGGEST WILL STRENGTHEN PRIOR TO ARRIVAL OVER THE REGION LATE SUN NIGHT INTO EARLY MON. GUIDANCE CONTINUES TO DELAY THE ONSET...ARRIVING ACROSS FAR NORTHWEST IL ARND 6-8Z. THEN POSSIBLY NOT REACHING ORD/MDW UNTIL ARND 10-12Z. IT STILL APPEARS FAVORABLE FOR LGT SNOW AND A PERIOD OF MODERATE SNOW MAY ACCOMPANY THE SYSTEM AROUND DAYBREAK MON FOR A FEW HOURS...WITH LIGHT ACCUMULATIONS. CIGS SHUD LOWER QUICKLY WITH THE STEADIER SNOW...AND MAY TOUCH IFR CONDS AS THE GRADIENT SLACKENS. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH FOR WINDS THRU THE PERIOD. * MEDIUM FOR PRECIP TIMING/DURATION/CIGS/VIS MONDAY MORNING. CMS //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...MAINLY VFR CONDS. PATCHY MVFR CIGS. TUESDAY...CHANCE OF RAIN TUESDAY AFTERNOON. RAIN LIKELY/THUNDER POSSIBLE AT NIGHT. MVFR/IFR POSSIBLE. BREEZY SOUTHEAST WINDS. WEDNESDAY...SLIGHT CHANCE OF SHOWERS WITH MVFR EARLY. GUSTY WEST- SOUTHWEST WINDS. THURSDAY...SLIGHT CHANCE OF SHOWERS. MVFR POSSIBLE. FRIDAY...VFR. SATURDAY...VFR. BEACHLER && .MARINE... 425 AM CDT A SURFACE RIDGE OF HIGH PRESSURE WILL SHIFT OVER SOUTHERN CANADA AND THE UPPER GREAT LAKES THROUGH MONDAY. THIS WILL RESULT IN A CONTINUED PERIOD OF NORTHERLY WINDS UP TO AROUND 20 KT TODAY AND TONIGHT. THEREFORE...EXPECT WAVES OF 3 TO 5 FEET TO CONTINUE FOR THE NEAR SHORE WATERS OF NORTHEASTERN ILLINOIS AND NORTHWESTERN INDIANA. ANOTHER STORM SYSTEM IS EXPECTED TO IMPACT THE WESTERN GREAT LAKES REGION LATE TUESDAY THROUGH WEDNESDAY. THE SURFACE LOW IS FORECAST TO TRACK EAST-NORTHEASTWARD FROM THE PLAINS TO THE UPPER GREAT LAKES BY WEDNESDAY MORNING. THIS LOOKS TO RESULT IN A PERIOD OF INCREASING SOUTHEASTERLY WINDS OF 25 TO 30 KT TUESDAY NIGHT...FOLLOWED BY A PERIOD OF STRONG WEST-SOUTHWESTERLY WINDS ON WEDNESDAY. GALE FORCE WINDS ARE POSSIBLE ON WEDNESDAY...ESPECIALLY ACROSS THE ILLINOIS AND INDIANA NEAR SHORES. WINDS WILL THEN SHIFT BACK OUT OF THE NORTH BY LATE WEEK AS A REINFORCING COLD FRONT DROPS SOUTHWARD DOWN THE LAKE. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1026 AM CDT SUN MAR 22 2015 .UPDATE... 1025 AM CDT ONLY SMALL CHANGES MADE TO THE FORECAST FOR THIS AFTERNOON. HAVE ADDED THE MENTION OF SOME FLURRIES OR POSSIBLY SPRINKLES THIS AFTERNOON IN FAR NORTHERN ILLINOIS...BUT AS FOR THIS EVENING CONTINUE TO DELAY MENTION OF MEASURABLE PRECIPITATION CHANCES. A CANOPY OF MID-LEVEL CLOUDS FROM SOUTHERN/CENTRAL MN THROUGH FAR NORTHERN IL AND SOUTHERN LAKE MI HIGHLIGHTS A WEAK ZONE OF MID-LEVEL FORCING ALONG A MODEST THERMAL GRADIENT. THE NATURE OF SOME OF THE SOUTHERN EDGE CLOUDS AS WELL AS 35-40DBZ ECHOES ON COMPOSITE RADAR NEAR THE IA/MN BORDER INDICATE THE PRESENCE OF AT LEAST WEAK INSTABILITY ALOFT AND LIKELY THE RESULT OF A SUBTLE MID-LEVEL PERTURBATION PER SATELLITE AND RAP ANALYSIS. IT IS POSSIBLE AS THIS CORRIDOR OF SHOWERY-TYPE ECHOES BRINGS SOME SPRINKLES OR FLURRIES TO FAR NORTHERN IL EARLY TO MID AFTERNOON...SO THAT IS WHY THE EARLIER MENTION IN THE FORECAST. OVERALL THOUGH...THE DRIER SYNOPTIC AIR AND DRY 925-850MB TRAJECTORIES WILL LIKELY PREVENT ANY NOTEWORTHY PRECIP INTO THIS EVE AND POSSIBLY THROUGH EARLY OVERNIGHT UNTIL STRONGER FORCING WITH THE MAIN UPPER SHORT WAVE APPROACH. THE CHALLENGE WITH THIS UPCOMING SNOW EVENT LOOKS TO BE IF THERE WILL BE A CORRIDOR/BAND OF MODERATE SNOWFALL RATES DURING THE DAYBREAK THROUGH MID-MORNING HOURS ON MONDAY...WHICH SOME HIGH RESOLUTION MODELS INCLUDING THE 12Z NAM INDICATE AND THIS MAKES SENSE SOMEWHERE IN THE REGION WITH THIS TYPE OF SYSTEM. IT IS JUST PLACEMENT AND DURATION IS THE CHALLENGE. THESE MORE APPRECIABLE RATES EVEN IF TEMPORARY WOULD HAVE AT LEAST A SLIGHTLY GREATER IMPACT DUE TO OVERCOMING THE NOW WARMER PAVEMENT AND GROUND TEMPERATURES. WILL CONTINUE TO LOOK AT GUIDANCE AND REFINE THE FORECAST WITH MORE TEMPORAL AND SPATIAL RESOLUTION FOR MONDAY MORNING AND IF NEEDED ISSUE SOME FORM OF STATEMENT TO FURTHER HIGHLIGHT. MTF && .SHORT TERM... 235 AM CDT THROUGH MONDAY... MAIN CONCERN IN THE SHORT TERM WILL REVOLVE AROUND TIMING OF A DEVELOPING MID-LVL SHORTWAVE FOR LATE TONIGHT INTO MONDAY MORNING...WHICH WILL LIKELY BRING SOME LIGHT ACCUMULATING SNOWFALL TO MAINLY NORTHERN IL. PRIOR TO THE ARRIVAL OF THIS SYSTEM...EARLY THIS MORNING THE SURFACE ANTI-CYCLONIC FEATURE REMAINED CENTERED OVER THE GREAT LAKES REGION. THIS FEATURE WAS SENDING MUCH DRIER AIR SOUTH ACROSS THE WESTERN GREAT LAKES WITH NUMEROUS LOCATIONS IN WISC SEEING DEW PTS IN THE SINGLE DIGITS TO LOW TEENS...ALTHOUGH ACROSS NORTHERN IL DEW PTS REMAINED IN THE LOW/MID 20S. THIS WAS A RESULT OF THE NORTHEAST WINDS ALLOWING THE MARINE ENVIRONMENT TO BLEED INLAND. GUIDANCE CONTINUES TO SUGGEST THE SFC RIDGE WILL REMAIN ORIENTED ACROSS THE UPPER MIDWEST/GREAT LAKES STRETCHING NORTH INTO CENTRAL ONTARIO THROUGH TONIGHT AND INTO MONDAY. THIS WILL MAINTAIN A COOL/DRY NORTHEAST TO EAST LLVL FLOW ACROSS THE FORECAST AREA. IR IMAGERY INDICATES A THIN CIRRUS SHIELD OVERHEAD...BUT WILL STEADILY THICKEN AS THE AFTN/EVE PROGRESSES. HIGHS TODAY WILL STRUGGLE TO WARM BEYOND THE LOW/MID 40S...WITH A FEW AREAS IN THE FAR SOUTHWEST NEARING 50. AREAS ADJACENT TO LAKE MICHIGAN WILL BE UNDER THE INFLUENCE OF A COLD MARINE ENVIRONMENT...LIKELY HOLDING TEMPS IN THE UPR 30S WITHIN THE FIRST FEW MILES OF LAND AWAY FROM THE LAKE. THE FOR TONIGHT...GUIDANCE HAS LOCKED IN THE DRY AIR WHICH APPEARS TO BE DELAYING THE MOISTENING LOW/MID LVLS UNTIL LATE TONIGHT. USING A T-LAG DISPLAY OF SOUNDINGS WOULD SUGGEST THE TREND HAS BEEN TO PUSH BACK PRECIP UNTIL ARND 6Z BUT THAT TOO COULD BE A FEW HOURS EARLY. HAVE HELD ONTO DRY CONDS LONGER WITH SLT CHC POPS ARRIVING ARND 6Z...THEN STEADILY INCREASING TO LIKELY ARND 9Z THRU ABOUT 12- 14Z. A BAROCLINIC ZONE WILL BE ORIENTED FROM SOUTHEAST IOWA EAST THROUGH CENTRAL IL INTO CENTRAL IN BY EARLY MON AFTN. THE LOW WILL LIKELY FOLLO THIS ORIENTATION AS IT NEARS THE REGION LATE TONIGHT. THERE CONTINUES TO BE SOME DEGREE OF UNCERTAINTY ON THE DURATION OF THE SNOW...HOWEVER DYNAMICALLY SPEAKING THE FORCING CRANKS UP LATE TONIGHT WITH STEEPING MID-LVL LAPSE RATES AND A TIGHTENING GRADIENT ALONG THE BAROCLINIC ZONE. WITH STRONG ASCENT ALONG THE LEADING EDGE...QUICK MOISTENING OF THE LLVLS SHUD OCCUR AND MAY ALLOW FOR A FEW HRS OF MODERATE SNOW BETWEEN 10-14Z...BEFORE THE PROFILE BEGINS TO WARM AND LIFT BEGINS TO DECREASE BY 15-17Z MON. SNOW ACCUMS ARE POSSIBLE AND TIMING APPEARS TO BE JUST PRIOR TO RUSH-HOUR MON MORNING...AND ENDING SHORTLY AFTER. CURRENT INDICATIONS ARE FOR ARND 1 INCH CLOSER TO CHICAGO...AND POSSIBLY UP TO 2 INCHES IN A FEW AREAS ALONG AND WEST OF A DIXON TO CRYSTAL LAKE LINE. THICK SOLAR SHIELDING WILL KEEP TEMPS WELL BELOW SEASONAL CONDS MON...WITH HIGHS MAINLY IN THE MID/UPR 30S. PRECIP SHUD BE ENDING BY EARLY AFTN MON. BEACHLER && .LONG TERM... 354 AM CDT MONDAY NIGHT THROUGH SATURDAY... ATTENTION DURING THE LONG TERM PERIOD IS MAINLY FOCUSED ON THE POTENTIAL FOR A GOOD STORM SYSTEM TO IMPACT THE REGION LATE TUESDAY THROUGH WEDNESDAY. MODEL GUIDANCE CONTINUES IN DECENT AGREEMENT WITH THE EVOLUTION OF A STORM SYSTEM ACROSS THE CENTRAL PORTION OF THE COUNTRY BY MID WEEK. UPPER LEVEL ENERGY EMANATING FROM THE NORTHEASTERN PACIFIC IS EXPECTED TO SHIFT EASTWARD ONSHORE ACROSS THE PACIFIC NORTHWEST BY MONDAY...THEN OVER THE ROCKIES BY TUESDAY MORNING. THIS SHOULD SPAWN SURFACE LOW PRESSURE OVER THE PLAINS DURING THE DAY TUESDAY. MODEL GUIDANCE IS ALSO INSISTENT THAT THE MAIN MID/UPPER LEVEL SHORT WAVE WILL BECOME NEGATIVELY TILTED AS IT MOVES OVER THE MID MISSOURI VALLEY LATE TUESDAY INTO TUESDAY NIGHT. AS SUCH...THIS IS SHAPING UP TO POSSIBLY BE A GOOD DYNAMIC SYSTEM CAPABLE OF PRODUCING THUNDERSTORMS OVER THE AREA...ESPECIALLY TUESDAY NIGHT...FOLLOWED BY SOME STRONG SYNOPIC WINDS INTO WEDNESDAY. IT CURRENTLY APPEARS THAT MOST OF NORTHERN ILLINOIS/NORTHWESTERN INDIANA MAY END UP STAYING DRY FOR MOST OF THE DAY TUESDAY AS MOST OF THE SHOWERS LOOK TO REMAIN FOCUSED DOWN STATE IN CLOSER PROXIMITY TO THE WARM FRONTAL BOUNDARY. FOR THIS REASON I HAVE CUT BACK ON POPS ACROSS NORTHERN ILLINOIS DURING THE DAY TUESDAY. THE BEST POTENTIAL FOR SHOWERS AND THUNDERSTORMS FOR THE AREA LOOKS TO BE TUESDAY EVENING AND INTO THE PREDAWN HOURS OF OF WEDNESDAY MORNING. THIS IS THE PERIOD WHEN THE MAIN MID LEVEL NEGATIVELY TILTED SYSTEM BEGINS TO SHIFT OVER NORTHERN ILLINOIS. AS THIS OCCURS...THE SURFACE LOW WILL ACCELERATE NORTHEASTWARD AND DEEPEN INTO WEDNESDAY. THIS WILL RAPIDLY SHIFT THE WARM FRONT AND BETTER MOISTURE FROM DOWNSTATE ILLINOIS RIGHT ACROSS THE AREA BY TUESDAY EVENING. THINGS LOOK TO DRY OUT IN A HURRY BY EARLY WEDNESDAY FOLLOWING THE PASSAGE OF THE MID LEVEL SYSTEM AND DRY PUNCH. THE MAIN WEATHER ISSUE ON WEDNESDAY WILL BE THE POTENTIAL FOR STRONG WEST- SOUTHWESTERLY WINDS. IT CURRENTLY APPEARS THAT WINDS COULD GUST TO AROUND 40 TO 45 MPH ON WEDNESDAY AS THE COMBINATION OF MUCH DRIER AIR...GOOD LARGE SCALE DECENT IN THE WAKE OF THE UPPER LEVEL SYSTEM AND SOME DECENT SURFACE PRESSURE RISES...COULD LEAD TO EFFICIENT ATMOSPHERIC MIXING OF STRONG WINDS OFF THE SURFACE. MID/UPPER LEVEL HEIGHTS ARE EXPECTED TO BUILD ACROSS WESTERN NORTH AMERICA BY MID WEEK...AND THIS WILL ULTIMATELY SET UP TROUGHING OVER THE EASTERN CONUS...FEATURING NORTHWEST FLOW ALOFT OVER THE WESTERN GREAT LAKES REGION. THEREFORE...MILD CONDITIONS TUESDAY NIGHT AND WEDNESDAY WILL TRANSITION TO COLDER WEATHER AGAIN BY THURSDAY AS THIS PATTERN ALLOWS MUCH COLDER AIR TO SPILL IN ACROSS THE EASTERN CONUS FOR THE LATER HALF OF THE WEEK. HIGHS WILL LIKELY END UP 10 TO 15 DEGREES BELOW AVERAGE FOR A FEW DAYS AT THE END OF THE PERIOD (30S TO LOW 40S). IT ALSO APPEARS THAT THERE COULD BE SOME PERIODIC EPISODES OF SNOW AND RAIN SHOWERS AS ADDITIONAL MID LEVEL DISTURBANCES SHIFT SOUTHEASTWARD ACROSS THE REGION. KJB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * NORTHEAST WINDS 10 TO 15 KT THRU THIS EVENING...WITH HIGHER GUSTS POSSIBLE. * SNOW DEVELOPING AROUND DAYBREAK MONDAY MORNING WITH MVFR CIGS/VIS...IFR POSSIBLE. CMS //DISCUSSION...UPDATED 12Z... HIGH PRESSURE REMAINS CENTERED TO THE NORTH OF THE REGION...AND WILL CONTINUE TO ALLOW NORTHEAST TO EAST WINDS THRU THE DURATION OF THE CURRENT TAF. WITH THE LACK OF MIXING OVERNIGHT...THE WIND SPEEDS HAVE FALLEN OFF SLIGHTLY. EXPECT SHORTLY AFTER DAYBREAK THE WIND SPEEDS TO PICK BACK UP AND GUSTS TO 15KT WILL BE FREQUENT. THE LOW/MID LVLS IN THE ATMOSPHERE REMAIN VERY DRY...WHICH WILL ALLOW MINIMAL CLOUDS IN THE LOWER LEVELS. A CIRRUS SHIELD WILL STEADILY THICKEN AND BEGIN TO LOWER...ALTHOUGH EXPECT VFR CONDS TO PREVAIL THRU AT LEAST 00Z AND POSSIBLY BEYOND 6Z MON TONIGHT. THE FOCUS THEN TURNS TOWARDS THE DEVELOPING LOW PRESSURE SYSTEM ACROSS THE CENTRAL PLAINS...THAT GUIDANCE HAS CONTINUED TO SUGGEST WILL STRENGTHEN PRIOR TO ARRIVAL OVER THE REGION LATE SUN NIGHT INTO EARLY MON. GUIDANCE CONTINUES TO DELAY THE ONSET...ARRIVING ACROSS FAR NORTHWEST IL ARND 6-8Z. THEN POSSIBLY NOT REACHING ORD/MDW UNTIL ARND 10-12Z. IT STILL APPEARS FAVORABLE FOR LGT SNOW AND A PERIOD OF MODERATE SNOW MAY ACCOMPANY THE SYSTEM AROUND DAYBREAK MON FOR A FEW HOURS...WITH LIGHT ACCUMULATIONS. CIGS SHUD LOWER QUICKLY WITH THE STEADIER SNOW...AND MAY TOUCH IFR CONDS AS THE GRADIENT SLACKENS. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 14Z... * HIGH FOR WINDS THRU THE PERIOD. * MEDIUM FOR PRECIP TIMING/DURATION/CIGS/VIS MONDAY MORNING. CMS //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...MAINLY VFR CONDS. PATCHY MVFR CIGS. TUESDAY...CHANCE OF RAIN TUESDAY AFTERNOON. RAIN LIKELY/THUNDER POSSIBLE AT NIGHT. MVFR/IFR POSSIBLE. BREEZY SOUTHEAST WINDS. WEDNESDAY...SLIGHT CHANCE OF SHOWERS WITH MVFR EARLY. GUSTY WEST- SOUTHWEST WINDS. THURSDAY...SLIGHT CHANCE OF SHOWERS. MVFR POSSIBLE. FRIDAY...VFR. SATURDAY...VFR. BEACHLER && .MARINE... 425 AM CDT A SURFACE RIDGE OF HIGH PRESSURE WILL SHIFT OVER SOUTHERN CANADA AND THE UPPER GREAT LAKES THROUGH MONDAY. THIS WILL RESULT IN A CONTINUED PERIOD OF NORTHERLY WINDS UP TO AROUND 20 KT TODAY AND TONIGHT. THEREFORE...EXPECT WAVES OF 3 TO 5 FEET TO CONTINUE FOR THE NEAR SHORE WATERS OF NORTHEASTERN ILLINOIS AND NORTHWESTERN INDIANA. ANOTHER STORM SYSTEM IS EXPECTED TO IMPACT THE WESTERN GREAT LAKES REGION LATE TUESDAY THROUGH WEDNESDAY. THE SURFACE LOW IS FORECAST TO TRACK EAST-NORTHEASTWARD FROM THE PLAINS TO THE UPPER GREAT LAKES BY WEDNESDAY MORNING. THIS LOOKS TO RESULT IN A PERIOD OF INCREASING SOUTHEASTERLY WINDS OF 25 TO 30 KT TUESDAY NIGHT...FOLLOWED BY A PERIOD OF STRONG WEST-SOUTHWESTERLY WINDS ON WEDNESDAY. GALE FORCE WINDS ARE POSSIBLE ON WEDNESDAY...ESPECIALLY ACROSS THE ILLINOIS AND INDIANA NEAR SHORES. WINDS WILL THEN SHIFT BACK OUT OF THE NORTH BY LATE WEEK AS A REINFORCING COLD FRONT DROPS SOUTHWARD DOWN THE LAKE. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1004 AM EDT SUN MAR 22 2015 .SYNOPSIS... LOW PRESSURE WILL CONTINUE TO INTENSIFY ACROSS THE MARITIMES TODAY AND TONIGHT. CANADIAN HIGH PRESSURE WILL BUILD EAST TOWARD THE REGION LATER MONDAY THROUGH TUESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 10 AM UPDATE: LOW PRESSURE NEAR THE EASTERN TIP OF NOVA SCOTIA WILL CONTINUE TO INTENSIFY AS IT ROTATES NORTHWEST ACROSS THE CANADIAN MARITIMES TODAY. A STRONG PRESSURE GRADIENT ACROSS THE AREA WILL RESULT IN GUSTY WEST WINDS TODAY ALONG WITH SOME LIGHT SNOW ACROSS NORTHERN AREAS. WINDS COULD GUST AS HIGH AS 45 TO 50 MPH AT TIMES ESPECIALLY ACROSS THE HIGHER TERRAIN. ANY ADDITIONAL SNOW ACCUMULATION WILL BE AN INCH OR LESS. THE BIGGER CONCERN WILL BE AREAS OF BLOWING SNOW MAINLY ACROSS NORTHERN AREAS THAT WILL ABRUPTLY REDUCE VISIBILITY AT TIMES ESPECIALLY ON NORTH-SOUTH ROADS. FOR THIS REASON, WE WILL KEEP THE WINTER WEATHER ADVISORY GOING TODAY. WILL ALSO KEEP THE WIND ADVISORY GOING ACROSS CENTRAL AND DOWN EAST AREAS FOR TODAY. ALL-IN-ALL, THE CURRENT FORECAST HAS THINGS COVERED QUITE NICELY AND NO SIGNIFICANT ADJUSTMENTS WERE MADE TO THE FORECAST ON THIS UPDATE. PREVIOUS DISCUSSION OTHERWISE...LATEST HRRR SIM RADAR IMAGERY SHOWS MUCH OF THE REMAINING PTN OF STEADY SN RETREATING INTO NRN NB BY LATE MORN. HELD OFF FOR NOW TO ADJUSTING POPS DOWNWARD OVR THE FAR N...SINCE LATEST 06Z SYNOPTIC MODELS STILL INDICATE A FEW HUNDREDTHS OF AN IN OF QPF OVR THIS PTN OF THE FA BETWEEN 12 AND 18Z (8AM-2PM) TODAY. ORGNL DISC: LATEST RADAR IMAGERY SHOWS THE BACK EDGE OF STEADY SNFL NOW SLIDING E OUT OF DOWNEAST AND CNTRL PTNS OF THE FA INTO NB PROV... BUT STILL HOLDING ACROSS NRN AND ERN AROOSTOOK COUNTY...AT LEAST FOR THE NEXT FEW HRS. AFTWRDS...WNW WINDS WILL DRAMATICALLY INCREASE ACROSS ALL OF THE REGION FOLLOWING THE PASSAGE OF AN ARCTIC FRONT WITHIN THE NEXT 1 TO 3 HRS. WIND GUSTS WILL BE REACHING MID TO HIGH END WIND ADV CRITERIA BY AFTN. HOWEVER... DUE TO MORE SNFL ACCUMULATION ACROSS THE N HLF OF THE FA...THE CONCERN IS MORE TOWARD BLSN...SO WE INCLUDED STRONG WINDS WITHIN THE WSW WNTR WX ADV STATEMENT. ACROSS THE SRN HLF OF THE FA WHERE THERE IS LESS ACCUMULATION...WE MENTION PATCHY BLSN WITHIN THE NPW WIND ADV STATEMENT. BOTH HDLNS ARE IN EFFECT UNTIL ERLY EVE... AFTER WHICH...WIND GUST POTENTIAL WILL SLOWLY DIMINISH OVRNGT. TEMPS WILL FALL SHARPLY ACROSS THE FA ERLY THIS MORN FOLLOWING THE ARCTIC FRONT...AND WILL NOT LIKELY MAKE MUCH GAIN THRU THE REMAINDER OF THE MORNG INTO ERLY AFTN...THEN FALL BY LATE AFTN...AS THE STRENGTHENING LATE MAR SUN ANGLE AND INCREASING DAYLENGTH IS ABOUT EVENLY MATCHED BY STRONG LLVL COLD ADVCN. MEANWHILE...THE BACK EDGE OF STEADY SN WILL NOT MAKE MUCH HEADWAY OUT OF XTRM NE PTNS OF THE FA DUE TO THE DEEPENING MARITIMES LOW...SO SCT SN SHWRS COULD AFFECT THE FAR N AND NE OF THE FA THRU THE REMAINDER OF THE DAY. INTERESTINGLY...TEMPS WILL CONT TO FALL THRU THE EVE...THEN LVL OFF LATE TNGT AND EVEN INCREASE BY DAYBREAK SPCLY ACROSS THE N HLF OF FA AS A WARM OCCLUSION FROM THE DEEPENING LOW WORKS IT WAY ALL THE WAY ARND THE N SIDE OF THE SYSTEM AND THEN BACK SW TOWARD THE GASPE PENINSULA. THIS WILL KEEP SCT SN SHWRS ACROSS THE NRN TWO THIRDS OF THE FA AND EVEN INTERMITTENT LGT SNFL GOING ACROSS THE FAR N AND NE WHILE CLDNSS SLIPS BACK TOWARD E CNTRL PTNS OF THE FA LATE TNGT. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... FOR MONDAY...WINDS AND CONTINUED COLD WILL BE THE PRIMARY FEATURES. HIGHS WILL MODERATE INTO THE 20S...BUT REMAIN FAR BELOW NORMAL. WINDS WILL GUST TOWARDS 35 MPH BY LATE MORNING IN NORTHERN ZONES. CLOUDY SKIES WILL PREVAIL EXCEPT IN THE DOWNSLOPE REGIONS AROUND BANGOR AND MUCH OF DOWN EAST. THE WINDS FINALLY DECREASE MONDAY NIGHT WITH RAPIDLY RISING SURFACE PRESSURE. LOWS WILL DROP INTO THE SINGLE DIGITS TO LOW TEENS. SUBZERO READINGS ARE POSSIBLE IN THE ALLAGASH WHERE WINDS WILL BE LIGHTEST. SUNSHINE WILL PROMOTE A NICE RECOVERY ON TUESDAY AND BRING HIGHS BACK ABOVE FREEZING FOR MOST LOCATIONS. MID TO UPPER 30S ARE PROBABLE FOR BANGOR AND DOWN EAST. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... A SHALLOW RADIATION INVERSION WILL DEVELOP ON TUESDAY NIGHT WITH WIDE VARIATIONS IN NIGHTTIME TEMPS. COLDER NORTHERN VALLEY COULD SEE SUBZERO READINGS WHILE HIGHER TERRAIN WILL STAY IN THE TEENS. THE SHALLOW INVERSION WILL BE QUICKLY ERASED WEDNESDAY MORNING AND TEMPERATURES WILL PUSH TOWARDS THE UPPER 30S AND LOWER 40S UNDER SUNNY SKIES. CLOUDS WILL INCREASE LATE AHEAD OF A LOW PROGGED TO TRACK ACROSS QUEBEC ON THURSDAY. THIS SYSTEM WILL BRING LIGHT AMOUNTS OF WARM ADVECTION SNOW WEDNESDAY NIGHT. THIS SNOW WILL QUICKLY MELT WITH HIGHS AGAIN REACHING THE MID 40S ON THURSDAY. THERE IS A LOT OF UNCERTAINTY AS TO HOW THINGS PLAY OUT AFTER THE WARM OCCLUSION ON WEDNESDAY NIGHT. A FRONTAL BOUNDARY IS EXPECTED TO BE STATIONARY JUST SOUTH OF THE FORECAST AREA THURSDAY. A COUPLE OF SOUTHERN STREAM SHORTWAVES ARE LIKELY TO MOVE NORTHEAST ALONG THE FRONTAL BOUNDARY. THESE SHORTWAVES HAVE THE POTENTIAL TO BRING QUITE A BIT OF RAIN. THE QUESTION IS EXACTLY WHERE THE BOUNDARY WILL SET UP AND WHICH SHORTWAVE WILL BE DOMINANT. FOR NOW...HAVE FOLLOWED AN ENSEMBLE APPROACH BEST MIRRORED BY THE OPERATIONAL ECMWF WHERE THE FIRST WAVE AFFECTS THE SOUTHERN THIRD OF THE FORECAST AREA THURSDAY AND THURSDAY EVENING WITH THE THREAT OF A HALF INCH OF RAIN AND WIDESPREAD FOG. BANGOR AND THE DOWN EAST REGION MAY STAY ABOVE THE FREEZING MARK FROM MIDDAY WEDNESDAY UNTIL FRIDAY NIGHT. THUS...THERE IS A THREAT THAT ICE WILL START MOVING AND JAMMING IN THE SOUTHERN PORTION OF THE FORECAST AREA BY THURSDAY NIGHT OR FRIDAY. IF THE SOUTHERN STREAM SHORTWAVE IS MORE POTENT THAN CURRENTLY EXPECTED...THERE COULD BE MORE WIDESPREAD FLOOD CONCERNS. A SECOND SHORTWAVE IS A THREAT TO AFFECT THE AREA LATER FRIDAY AND FRIDAY NIGHT...BUT WILL FORECAST IT TO MOVE SOUTH OF THE AREA FOR NOW. INSTEAD...WILL BRING A COLD FRONT ACROSS THE AREA ON FRIDAY THAT WILL BRING THE SUBFREEZING TEMPERATURES BACK TO BANGOR AND DOWN EAST ON FRIDAY NIGHT. THAT SAID...THERE IS LOW CONFIDENCE ON THE EVOLUTION AND MOVEMENT OF AN UPPER TROUGH MOVING OUT OF THE MIDWEST THURSDAY THROUGH FRIDAY NIGHT. THERE IS RISK OF SIGNIFICANT RAINFALL...SNOWMELT AND ICE JAMS DURING THIS PERIOD. THE BIGGEST RISK WILL BE IN THE SOUTHERN HALF OF THE FORECAST AREA WHERE TEMPERATURES WILL BE HIGHER. THE CHANCES OF HEAVIER RAINFALL WILL BE GREATER THERE AS WELL. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... NEAR TERM: IFR TO MVFR CONDITIONS XPCTD TDY ACROSS NRN TAF SITES IN FALLING SN TRANSITIONING TO BLSN AS FALLING SN IS REPLACED BY STRONG NW WINDS. DOWNEAST SITES WILL BE MSLY VFR TDY...WITH BRIEF MVFR IN BLSN POSSIBLE. NRN TAF SITES WILL THEN IMPROVE TO LOW VFR TO HI MVFR SC CLGS TNGT AS WIND GUSTS LOWER SOMEWHAT REDUCING BLSN WHILE DOWNEAST SITES BECOME STEADY VFR. SHORT TERM: MVFR CIGS FROM HUL NORTHWARD ON MONDAY. OTHERWISE VFR FOR ALL TERMINALS UNTIL WEDNESDAY NIGHT. EXPECT PREDOMINANT IFR WEDNESDAY NIGHT INTO THURSDAY WITH THE CHANCE OF FOG ON THURSDAY. && .MARINE... NEAR TERM: WILL CONT WITH THE CURRENT GLW AND FZGSPY ADV AS INITIALLY WINDS INCREASE ERLY THIS MORN BEHIND THE ARCTIC FRONT WITH THE FZGSPY ADV DELAYED A FEW HRS TO ALLOW COLDER AIR TO WORK OVR THE WATERS. BOTH HDLNS THEN REMAIN IN EFFECT THRU THE REMAINDER OF THE NEAR TERM THRU ALL OF SUN NGT. SHORT TERM: THE GALE AND FREEZING SPRAY WILL END LATER MONDAY MORNING AND GIVE WAY TO AN SCA THAT WILL CONTINUE INTO MONDAY EVENING. THE NEXT CONCERN WILL BE A STRONG SCA ON WEDNESDAY NIGHT INTO THURSDAY. SEAS COULD REACH 15 FEET IN A SOUTH SWELL. WINDS WILL BE THE LESSER CONCERN WITH THIS EVENT. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MEZ001>006-010. WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MEZ011-015>017- 029>032. MARINE...FREEZING SPRAY ADVISORY UNTIL 11 AM EDT MONDAY FOR ANZ050>052. GALE WARNING UNTIL 11 AM EDT MONDAY FOR ANZ050>052. && $$ NEAR TERM...DUDA/VJN SHORT TERM...MCW LONG TERM...MCW/BERDES AVIATION...DUDA/VJN/MCW MARINE...DUDA/VJN/MCW
AREA FORECAST DISCUSSION
NWS CARIBOU ME
627 AM EDT SUN MAR 22 2015 .SYNOPSIS... LOW PRESSURE WILL CONTINUE TO INTENSIFY ACROSS THE MARITIMES TODAY AND TONIGHT. CANADIAN HIGH PRESSURE WILL BUILD EAST TOWARD THE REGION LATER MONDAY THROUGH TUESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 615 AM UPDATE: NO SIG CHGS THIS UPDATE. OF COURSE...TEMPS HAVE FALLEN FASTER THAN WHAT WAS EARLIER FCST BY INTERPOLATION. SO WE LOADED BOTH 5 AND 6 AM OBSVD TEMPS AND MADE CHGS TO THE PRIOR NGT`S FCST LOW TEMPS...WHICH MSLY FEATURED COLDER LOWS OVR THE FAR W. WE DID NOT ADJUST HI TEMPS THIS AFTN ATTM. SINCE TEMPS ERLY THIS MORN DID GET COLDER THEN PREV OVRNGT LOWS OVR THE W...IT IS CONCEIVABLE THAT THERE COULD BE SOME RECOVERY OF TEMPS THERE LATER THIS MORN INTO ERLY AFTN. OTHERWISE...LATEST HRRR SIM RADAR IMAGERY SHOWS MUCH OF THE REMAINING PTN OF STEADY SN RETREATING INTO NRN NB BY LATE MORN. HELD OFF FOR NOW TO ADJUSTING POPS DOWNWARD OVR THE FAR N...SINCE LATEST 06Z SYNOPTIC MODELS STILL INDICATE A FEW HUNDREDTHS OF AN IN OF QPF OVR THIS PTN OF THE FA BETWEEN 12 AND 18Z (8AM-2PM) TODAY. ORGNL DISC: LATEST RADAR IMAGERY SHOWS THE BACK EDGE OF STEADY SNFL NOW SLIDING E OUT OF DOWNEAST AND CNTRL PTNS OF THE FA INTO NB PROV... BUT STILL HOLDING ACROSS NRN AND ERN AROOSTOOK COUNTY...AT LEAST FOR THE NEXT FEW HRS. AFTWRDS...WNW WINDS WILL DRAMATICALLY INCREASE ACROSS ALL OF THE REGION FOLLOWING THE PASSAGE OF AN ARCTIC FRONT WITHIN THE NEXT 1 TO 3 HRS. WIND GUSTS WILL BE REACHING MID TO HIGH END WIND ADV CRITERIA BY AFTN. HOWEVER... DUE TO MORE SNFL ACCUMULATION ACROSS THE N HLF OF THE FA...THE CONCERN IS MORE TOWARD BLSN...SO WE INCLUDED STRONG WINDS WITHIN THE WSW WNTR WX ADV STATEMENT. ACROSS THE SRN HLF OF THE FA WHERE THERE IS LESS ACCUMULATION...WE MENTION PATCHY BLSN WITHIN THE NPW WIND ADV STATEMENT. BOTH HDLNS ARE IN EFFECT UNTIL ERLY EVE... AFTER WHICH...WIND GUST POTENTIAL WILL SLOWLY DIMINISH OVRNGT. TEMPS WILL FALL SHARPLY ACROSS THE FA ERLY THIS MORN FOLLOWING THE ARCTIC FRONT...AND WILL NOT LIKELY MAKE MUCH GAIN THRU THE REMAINDER OF THE MORNG INTO ERLY AFTN...THEN FALL BY LATE AFTN...AS THE STRENGTHENING LATE MAR SUN ANGLE AND INCREASING DAYLENGTH IS ABOUT EVENLY MATCHED BY STRONG LLVL COLD ADVCN. MEANWHILE...THE BACK EDGE OF STEADY SN WILL NOT MAKE MUCH HEADWAY OUT OF XTRM NE PTNS OF THE FA DUE TO THE DEEPENING MARITIMES LOW...SO SCT SN SHWRS COULD AFFECT THE FAR N AND NE OF THE FA THRU THE REMAINDER OF THE DAY. INTERESTINGLY...TEMPS WILL CONT TO FALL THRU THE EVE...THEN LVL OFF LATE TNGT AND EVEN INCREASE BY DAYBREAK SPCLY ACROSS THE N HLF OF FA AS A WARM OCCLUSION FROM THE DEEPENING LOW WORKS IT WAY ALL THE WAY ARND THE N SIDE OF THE SYSTEM AND THEN BACK SW TOWARD THE GASPE PENINSULA. THIS WILL KEEP SCT SN SHWRS ACROSS THE NRN TWO THIRDS OF THE FA AND EVEN INTERMITTENT LGT SNFL GOING ACROSS THE FAR N AND NE WHILE CLDNSS SLIPS BACK TOWARD E CNTRL PTNS OF THE FA LATE TNGT. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... FOR MONDAY...WINDS AND CONTINUED COLD WILL BE THE PRIMARY FEATURES. HIGHS WILL MODERATE INTO THE 20S...BUT REMAIN FAR BELOW NORMAL. WINDS WILL GUST TOWARDS 35 MPH BY LATE MORNING IN NORTHERN ZONES. CLOUDY SKIES WILL PREVAIL EXCEPT IN THE DOWNSLOPE REGIONS AROUND BANGOR AND MUCH OF DOWN EAST. THE WINDS FINALLY DECREASE MONDAY NIGHT WITH RAPIDLY RISING SURFACE PRESSURE. LOWS WILL DROP INTO THE SINGLE DIGITS TO LOW TEENS. SUBZERO READINGS ARE POSSIBLE IN THE ALLAGASH WHERE WINDS WILL BE LIGHTEST. SUNSHINE WILL PROMOTE A NICE RECOVERY ON TUESDAY AND BRING HIGHS BACK ABOVE FREEZING FOR MOST LOCATIONS. MID TO UPPER 30S ARE PROBABLE FOR BANGOR AND DOWN EAST. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... A SHALLOW RADIATION INVERSION WILL DEVELOP ON TUESDAY NIGHT WITH WIDE VARIATIONS IN NIGHTTIME TEMPS. COLDER NORTHERN VALLEY COULD SEE SUBZERO READINGS WHILE HIGHER TERRAIN WILL STAY IN THE TEENS. THE SHALLOW INVERSION WILL BE QUICKLY ERASED WEDNESDAY MORNING AND TEMPERATURES WILL PUSH TOWARDS THE UPPER 30S AND LOWER 40S UNDER SUNNY SKIES. CLOUDS WILL INCREASE LATE AHEAD OF A LOW PROGGED TO TRACK ACROSS QUEBEC ON THURSDAY. THIS SYSTEM WILL BRING LIGHT AMOUNTS OF WARM ADVECTION SNOW WEDNESDAY NIGHT. THIS SNOW WILL QUICKLY MELT WITH HIGHS AGAIN REACHING THE MID 40S ON THURSDAY. THERE IS A LOT OF UNCERTAINTY AS TO HOW THINGS PLAY OUT AFTER THE WARM OCCLUSION ON WEDNESDAY NIGHT. A FRONTAL BOUNDARY IS EXPECTED TO BE STATIONARY JUST SOUTH OF THE FORECAST AREA THURSDAY. A COUPLE OF SOUTHERN STREAM SHORTWAVES ARE LIKELY TO MOVE NORTHEAST ALONG THE FRONTAL BOUNDARY. THESE SHORTWAVES HAVE THE POTENTIAL TO BRING QUITE A BIT OF RAIN. THE QUESTION IS EXACTLY WHERE THE BOUNDARY WILL SET UP AND WHICH SHORTWAVE WILL BE DOMINANT. FOR NOW...HAVE FOLLOWED AN ENSEMBLE APPROACH BEST MIRRORED BY THE OPERATIONAL ECMWF WHERE THE FIRST WAVE AFFECTS THE SOUTHERN THIRD OF THE FORECAST AREA THURSDAY AND THURSDAY EVENING WITH THE THREAT OF A HALF INCH OF RAIN AND WIDESPREAD FOG. BANGOR AND THE DOWN EAST REGION MAY STAY ABOVE THE FREEZING MARK FROM MIDDAY WEDNESDAY UNTIL FRIDAY NIGHT. THUS...THERE IS A THREAT THAT ICE WILL START MOVING AND JAMMING IN THE SOUTHERN PORTION OF THE FORECAST AREA BY THURSDAY NIGHT OR FRIDAY. IF THE SOUTHERN STREAM SHORTWAVE IS MORE POTENT THAN CURRENTLY EXPECTED...THERE COULD BE MORE WIDESPREAD FLOOD CONCERNS. A SECOND SHORTWAVE IS A THREAT TO AFFECT THE AREA LATER FRIDAY AND FRIDAY NIGHT...BUT WILL FORECAST IT TO MOVE SOUTH OF THE AREA FOR NOW. INSTEAD...WILL BRING A COLD FRONT ACROSS THE AREA ON FRIDAY THAT WILL BRING THE SUBFREEZING TEMPERATURES BACK TO BANGOR AND DOWN EAST ON FRIDAY NIGHT. THAT SAID...THERE IS LOW CONFIDENCE ON THE EVOLUTION AND MOVEMENT OF AN UPPER TROUGH MOVING OUT OF THE MIDWEST THURSDAY THROUGH FRIDAY NIGHT. THERE IS RISK OF SIGNIFICANT RAINFALL...SNOWMELT AND ICE JAMS DURING THIS PERIOD. THE BIGGEST RISK WILL BE IN THE SOUTHERN HALF OF THE FORECAST AREA WHERE TEMPERATURES WILL BE HIGHER. THE CHANCES OF HEAVIER RAINFALL WILL BE GREATER THERE AS WELL. && .AVIATION /10Z SUNDAY THROUGH THURSDAY/... NEAR TERM: IFR TO MVFR CONDITIONS XPCTD TDY ACROSS NRN TAF SITES IN FALLING SN TRANSITIONING TO BLSN AS FALLING SN IS REPLACED BY STRONG NW WINDS. DOWNEAST SITES WILL BE MSLY VFR TDY...WITH BRIEF MVFR IN BLSN POSSIBLE. NRN TAF SITES WILL THEN IMPROVE TO LOW VFR TO HI MVFR SC CLGS TNGT AS WIND GUSTS LOWER SOMEWHAT REDUCING BLSN WHILE DOWNEAST SITES BECOME STEADY VFR. SHORT TERM: MVFR CIGS FROM HUL NORTHWARD ON MONDAY. OTHERWISE VFR FOR ALL TERMINALS UNTIL WEDNESDAY NIGHT. EXPECT PREDOMINANT IFR WEDNESDAY NIGHT INTO THURSDAY WITH THE CHANCE OF FOG ON THURSDAY. && .MARINE... NEAR TERM: WILL CONT WITH THE CURRENT GLW AND FZGSPY ADV AS INITIALLY WINDS INCREASE ERLY THIS MORN BEHIND THE ARCTIC FRONT WITH THE FZGSPY ADV DELAYED A FEW HRS TO ALLOW COLDER AIR TO WORK OVR THE WATERS. BOTH HDLNS THEN REMAIN IN EFFECT THRU THE REMAINDER OF THE NEAR TERM THRU ALL OF SUN NGT. SHORT TERM: THE GALE AND FREEZING SPRAY WILL END LATER MONDAY MORNING AND GIVE WAY TO AN SCA THAT WILL CONTINUE INTO MONDAY EVENING. THE NEXT CONCERN WILL BE A STRONG SCA ON WEDNESDAY NIGHT INTO THURSDAY. SEAS COULD REACH 15 FEET IN A SOUTH SWELL. WINDS WILL BE THE LESSER CONCERN WITH THIS EVENT. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MEZ001>006-010. WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MEZ011-015>017- 029>032. MARINE...FREEZING SPRAY ADVISORY FROM 10 AM THIS MORNING TO 11 AM EDT MONDAY FOR ANZ050>052. GALE WARNING UNTIL 11 AM EDT MONDAY FOR ANZ050>052. && $$ NEAR TERM...VJN SHORT TERM...MCW LONG TERM...MCW/BERDES AVIATION...VJN/MCW MARINE...VJN/MCW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
729 AM EDT SUN MAR 22 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 502 AM EDT SUN MAR 22 2015 DESPITE 850MB TEMPS AROUND -17C PER LATEST RAP ANALYSIS...THERE ARE NO LAKE EFFECT CLOUDS DEVELOPING OFF THE OPEN WATER OF NCNTRL LAKE SUPERIOR. EVEN OFF THE OPEN WATER EXTENDING FROM THE KEWEENAW TO MUNISING...THERE WAS A LITTLE BURST OF LES EARLIER IN THE NIGHT INTO ALGER COUNTY...BUT THAT HAS SINCE DISSIPATED. CONVERGENCE HAS RECENTLY STRENGTHENED OVER THAT OPEN WATER AREA AS A WIND SHIFT TO THE ENE IS PROGRESSING TOWARD THE MARQUETTE COUNTY SHORELINE WHERE LAND BREEZE IS EVIDENT. IN JUST IN THE LAST HR...THIS HAS RESULTED IN NEW LIGHT LES DEVELOPMENT OVER FAR ERN MARQUETTE COUNTY. OTHERWISE...AS OF 09Z...THAT IS IT FOR LES AND EVEN LAKE EFFECT CLOUDS OFF LAKE SUPERIOR. UPSTREAM 00Z SOUNDINGS AT KINL/CYPL TELL THE STORY AS NOT ONLY WAS THE AIR MASS DRY IN THE LOW TO MID LEVELS...BUT BOTH SOUNDINGS ALSO EXHIBITED THE HOSTILE FOR LES INVERTED V LOOK. WOULD EXPECT A CONTINUED UPTICK IN LES OFF SCNTRL LAKE SUPERIOR INTO FAR ERN MARQUETTE COUNTY AND ALGER COUNTY EARLY THIS MORNING AS WE APPROACH THE COOLEST PART OF THE DIURNAL CYCLE/MOST FAVORABLE TIME OF DAY FOR LES AT THIS TIME OF YEAR. THAT SAID...IT WON`T BE MORE THAN LIGHT SNOW SHOWERS AND FLURRIES WITH ANY ACCUMULATION UNDER 1 INCH. THE DISRUPTIVE EFFECT OF DAYTIME HEATING AT THIS TIME OF YEAR COMBINED WITH 850MB THERMAL TROF SHIFTING E WILL BRING AN END TO THE LIGHT LES EARLY THIS AFTN. ACROSS THE REST OF THE FCST AREA...EXPECT A PARTLY TO MOSTLY SUNNY DAY WITH HIGHS IN THE 20S ACROSS MOST OF THE N AND E TO THE 30S TOWARD THE MI/WI BORDER. SHORTWAVE MOVING ACROSS THE DAKOTAS TODAY AND INTO THE WRN GREAT LAKES TONIGHT WILL WEAKEN AS IT ENCOUNTERS INCREASINGLY CONFLUENT FLOW. MODELS SHOW THIS WAVE SPREADING PCPN ACROSS MN INTO WI. MODELS WHICH HAD PREVIOUSLY BROUGHT THE PCPN TO NEAR THE MI/WI BORDER TONIGHT HAVE TRENDED S WITH THE NRN EDGE OF THE PCPN. GIVEN THE CONFLUENT FLOW OVER THE UPPER LAKES...ESTABLISHED ARCTIC AIR AND CONTINUED DRY AIR EMANATING FROM THE SFC HIGH PRES AREA WHICH WILL BE SLOWLY DRIFTING E OF HERE...A DRY FCST IS THE WAY TO GO TONIGHT. MIN TEMPS TONIGHT COULD BE QUITE LOW...ESPECIALLY OVER THE ERN FCST AREA WHERE HIGH/MID CLOUDS WILL BE THINNEST AND WHERE THERE WILL BE LIGHT ENE WINDS OFF ONTARIO. EXPECT TRADITIONAL COLD SPOTS TO FALL TO NEAR 0F OR EVEN BLO. DEPENDING ON THICKNESS OF CLOUDS...SINGLE DIGITS ABOVE ZERO MAY BE COMMON IN THE INTERIOR WESTWARD INTO CNTRL UPPER MI. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 451 AM EDT SUN MAR 22 2015 AT 12Z MONDAY UPPER MI WILL STILL BE IN BETWEEN SYSTEMS. THE NEXT SHORTWAVE WILL BE OVER S MANITOBA. HIGH PRESSURE WILL STILL BE THE MAIN FEATURE...CENTERED OVER THE E HALF OF ONTARIO/E LAKE SUPERIOR/E UPPER MI. NOT EXPECTING MUCH OUT OF THE SHORTWAVE TO THE NW AS IT WORKS THROUGH A REGION OF PRETTY DRY AIR. THE PRECIP OVER NW MN MONDAY AFTERNOON IS EXPECTED TO ALL BUT DRY UP AS IT CROSSES MN AND W LAKE SUPERIOR. DID KEEP JUST A SMALL POCKET OF SLIGHT CHANCE POPS OVER W LAKE SUPERIOR MONDAY NIGHT...AND N LAKE SUPERIOR LATE MONDAY NIGHT/TUESDAY MORNING. THE SFC HIGH WILL SLIDE TO THE SE OVER FAR SE ONTARIO/S QUEBEC BY TUESDAY MORNING. LOOK FOR THE RETURN OF S WINDS ON TUESDAY...WITH 850MB TEMPS RISING TO C TO -2C BY THE END OF THE DAY. DOWNSLOPE AREAS AND LOCATIONS ALONG THE WI BORDER MAY SEE TEMPS IN THE UPPER 40S TO NEAR 50F...ESPECIALLY IF THE ANTICIPATED MOSTLY SUNNY SKY PANS OUT. SLOWED DOWN/BROUGHT MORE TEMPORAL DEFINITION TO THE INCOMING SNOW AND MIXED PRECIP LATE TUESDAY NIGHT. THERE IS STILL ENOUGH UNCERTAINTY IN THE FCST SOLUTIONS TO KEEP THE MENTION OF SEVERAL INCHES OF SNOW POSSIBLE IN THE HWO FOR LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING. EXPECT SFC LOWS FROM THE DAKOTAS AND E KS TUESDAY AFTERNOON TO MERGE ACROSS WI BY DAYBREAK WEDNESDAY. 850MB WINDS OUT OF THE S AT 40- 50KTS WILL BE OUT AHEAD OF THE LOW /ACROSS LAKE MI AT 12Z WEDNESDAY/...USHERING IN WARMER AIR. LOOKS LIKE A GOOD CHANCE OF MIXED PRECIP STILL OVER S CENTRAL AND E UPPER MI WEDNESDAY AFTERNOON...WHICH WILL MINIMIZE THE POTENTIAL FOR QUICKLY ACCUMULATING SNOW. DEF/LIKELY SNOW WILL EXIT WEDNESDAY AFTERNOON AS THE CONSOLIDATED LOW EXITS FROM E UPPER MI TO E ONTARIO. OTHERWISE...PRECIP SHOULD STAY MAINLY IN THE FORM OF SNOW NW OF A LINE FROM IRON TO MUNISING. MODERATE SNOW WILL BE POSSIBLE OVER THE FAR W...DIMINISHING TO A GOOD CHANCE AS STEADY N TO NW WINDS TAKE HOLD AND COLDER AIR PUSHES IN ON THURSDAY. 850MB TEMPS WILL FALL TO - 18 TO -22C THURSDAY AFTERNOON INTO EARLY FRIDAY MORNING. LIGHTER AND LESS FAVORABLE W TO SW WINDS SHOULD PUSH IN LATER FRIDAY...AS ANOTHER AREA OF HIGH PRESSURE SINKS IN FROM S CENTRAL CANADA. LOOKING FARTHER OUT...MODELS ARE HINTING AT ANOTHER SYSTEM FOR THE END OF THE WEEKEND. STAY TUNED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 729 AM EDT SUN MAR 22 2015 DRY AIR MASS ASSOCIATED WITH HIGH PRES DRIFTING OVER NORTHERN ONTARIO TODAY AND TONIGHT WILL RESULT IN VFR CONDITIONS AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 502 AM EDT SUN MAR 22 2015 JUST AHEAD OF A HIGH PRES RIDGE EXTENDING SE OVER WRN LAKE SUPERIOR...NW WINDS OVER FAR ERN LAKE SUPERIOR WILL PROBABLY INCREASE TO 15-25KT TODAY. OTHERWISE...WINDS WILL BE UNDER 20KT. WINDS WILL THEN BE UNDER 20KT ACROSS THE LAKE TONIGHT AS THE HIGH PRES RIDGE DRIFTS E. WINDS SHOULD GENERALLY REMAIN UNDER 20KT MON INTO EARLY TUE AS PRES GRADIENT REMAINS WEAK. ATTENTION THEN TURNS TO DEEPENING LOW PRES WHICH WILL TRACK FROM THE CNTRL PLAINS TUE TO EASTERN UPPER MI WED AFTN. AHEAD OF THIS SYSTEM...SE TO E WINDS WILL INCREASE TUE NIGHT TO 15-25KT ACROSS MUCH OF LAKE SUPERIOR. WINDS WILL THEN VEER AROUND TO THE N WED/THU. WHILE 15-25KT WINDS WILL PROBABLY BE COMMON...WILL NEED TO WATCH FOR STRONGER WINDS UP TO 30KT AND POTENTIALLY UP TO GALE FORCE AT SOME POINT WED INTO EARLY THU FOR PARTS OF LAKE SUPERIOR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
656 AM CDT SUN MAR 22 2015 .UPDATE...FOR 12Z AVIATION DISCUSSION BELOW && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 355 AM CDT SUN MAR 22 2015 AN EARLY SPRING ACCUMULATING SNOWFALL EVENT IS ON TRACK FOR LATER TODAY AND TONIGHT...AS A SHORTWAVE TROUGH ADVANCES INTO THE AREA FROM THE NORTHERN ROCKIES. STILL LOOKS LIKE A 75 MILE WIDE BAND OF 3- 6 INCH ACCUMULATIONS WILL OCCUR FROM CENTRAL TO SOUTHEASTERN MINNESOTA. DESPITE THE FACT THIS SYSTEM IS NOW IN THE NEAR-TERM PORTION OF THE FORECAST...A FEW UNCERTAINTIES STILL REMAIN. THE FIRST UNKNOWN IS HOW LONG IT WILL TAKE THE DRY LOWER LAYERS OF THE ATMOSPHERE /UNDER THE INFLUENCE OF DRY NORTHEAST FLOW/ TO SATURATE. THIS WILL MEAN THE FIRST WARM AIR ADVECTION WAVE COULD ADD OR SUBTRACT 1-2 INCHES FROM EVENT TOTALS. GIVEN DEWPOINTS ARE IN THE SINGLE DIGITS TO LOWER TEENS...AM LEANING TOWARD IT TAKING LONGER FOR US TO SEE SATURATION AND THEREFORE A SLIGHTLY DELAYED SNOWFALL ONSET. A MORE PROBABLE SCENARIO IS THAT SNOW BEGINS ACROSS CENTRAL MN BETWEEN 16Z AND 18Z...AND THEN BLOSSOMS NOTABLY AFTER 21Z WHEN UPWARD MOTION MAXIMIZES. HAVE MAINTAINED THE HIGHEST POPS IN THE LATE AFTERNOON AND EARLY EVENING. THE CURRENT ADVISORY LOOKS TO BE IN GOOD SHAPE...WITH 3 TO 6 INCH ACCUMULATIONS. COULD SEE AMOUNTS SNEAK INTO WARNING CRITERIA RANGES /6+ INCHES/...HOWEVER GIVEN THE HUNCH THAT DRIER AIR MIGHT BE A BIT MORE IMPACTFUL THAN SEVERAL MODELS DEPICT...WILL HOLD TIGHT WITH THE ADVISORY FOR NOW. COULD ALSO HEAR SOME THUNDER ALONG THE IOWA BORDER...BUT FOR THE MOST PART DO NOT ANTICIPATE ENHANCED SNOWFALL RATES DUE TO THUNDERSNOW. AS THE DENDRITIC LAYER LOSES SATURATION AS THE EVENT IS WINDING DOWN...COULD SEE LIGHT FREEZING DRIZZLE FOR A FEW HOURS TONIGHT BEFORE PRECIPITATION SHUTS OFF ENTIRELY. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 355 AM CDT SUN MAR 22 2015 THE LONG TERM PORTION OF THE FORECAST PUTS A MOMENTARY PAUSE IN OUR SPRING WARMUP AS IT WILL FEATURE HIGHS STRUGGLING TO GET INTO THE 40S NEXT WORK WEEK...HAVE AN OPPORTUNITY FOR GETTING LOWS DOWN INTO THE SINGLE DIGITS...AND IS STARTING TO LOOK MORE LIKELY THAT IT WILL OFFER YET ANOTHER ACCUMULATING SNOW TUESDAY NIGHT AND WEDNESDAY. WE GET THINGS KICKED OFF ON MONDAY WITH TODAYS PRECIP CLEARING SE MN EARLY MONDAY MORNING. IN ITS WAKE WE WILL HAVE CLOUDY SKIES AND SOUTHEAST WINDS. GIVEN THE ANTICIPATION OF SEVERAL INCHES OF SNOW BEING ON THE GROUND...FOLLOWED THE MODEL BLEND IDEA WITH COOLING HIGHS ALONG A MORRIS TO ROCHESTER LINE...WHERE HIGHS IN THE 30S ARE LOOKING LIKELY. IN FACT...WE MAY NOT BE COLD ENOUGH WITH HIGHS WITHIN THE SWATH WHERE SNOW EVENTUALLY FALLS. OF MORE IMPORTANCE THOUGH ON MONDAY WILL BE THE NEGATIVELY TILTED H5 TROUGH WORKING ACROSS THE ROCKIES...WHICH WILL HEAD ACROSS THE UPPER MS VALLEY TUESDAY NIGHT. THERE WERE THREE SIGNIFICANT TRENDS WITH THE 00Z MODEL RUNS WITH THIS SYSTEM. THEY ALL SHOW THIS SYSTEM BEING SLOWER...FARTHER SOUTH...AND COLDER. ALL OF THIS POINTS TO INCREASING POTENTIAL FOR ANOTHER ROUND OF ACCUMULATING SNOWFALL...ESPECIALLY ACROSS CENTRAL/NRN MN INTO NW WI. THESE SHIFTS REPRESENT THE GFS SLOWING MORE TOWARD THE ECMWF /WHICH SLOWED DOWN AS WELL/ AND THE ECMWF SHIFTING SOUTH WITH THE SFC LOW...MORE TOWARD THE GEM/GFS. THIS SLOWER TREND IS LIKELY DUE TO THE FACT THAT THE SE LOW LEVEL WINDS WE WILL HAVE MONDAY/MONDAY NIGHT WILL BE EMANATING FROM A VERY DRY SFC HIGH OVER THE GREAT LAKES. IN FACT...THIS IS THE SAME SFC HIGH THAT BROUGHT US DEWPS IN THE SINGLE DIGITS ON SATURDAY AND IS PLAYING HAVOC WITH WHEN PRECIP WILL START TODAY. WE STILL HAVE LIKELY/DEFINITE POPS FOR THIS SYSTEM...THEY ARE JUST MORE TUESDAY NIGHT AS OPPOSED TO TUESDAY AFTERNOON/EVENING. THE SOUTHWARD SHIFT AND LATER ARRIVAL OF THIS PRECIP IS NOW STARTING TO BRING P-TYPE MUCH MORE INTO QUESTION. DID COOL TEMPS TUESDAY NIGHT SOME FROM PREVIOUS FORECAST...BUT NOT ENOUGH TO BRING ALL SNOW SOUTH OF CENTRAL MN AND NW WI. WHAT IS INTERESTING NOW IS THAT THE SFC LOW TRACK SEEN WITH THE ECMWF/GEM/GFS FROM CENTRAL IA TO NORTH CENTRAL WI IS A CLIMATOLOGICALLY FAVORED ONE FOR BRINGING HEAVY SNOWS INTO THE TWIN CITIES...SO WE MAY HAVE TO RATCHET TO FORECAST MORE IN THE SNOW DIRECTION IF THIS TREND HOLDS IN THE 12Z MODEL CYCLE. RIGHT NOW...WE HAVE A COUPLE INCHES OF SNOW ALONG THE NRN BORDER OF THE MPX AREA...WITH THE HEAVIEST SNOW /POSSIBLY PUSHING DOUBLE DIGITS IN TOTALS/ FALLING ACROSS NRN MN. FOR WEDNESDAY MODELS CONTINUE TO SHOW AN INVERTED TROUGH AND ASSOCIATED DEFORMATION ZONE HANGING UP TO THE WEST OF THE SFC LOW. THIS LOOKS TO BRING LIGHT PRECIP MOST OF THE DAY TO NORTHERN MN...WITH THE REMNANTS OF THAT DEFORMATION BAND PUSHING ACROSS ERN MN/WRN WI WEDNESDAY NIGHT. IN FACT...THE GFS SHOWS SNOW LINGERING ACROSS THE AREA THROUGH THURSDAY BEFORE AN ARCTIC FRONT FINALLY PUSHES THE MOISTURE SOUTHEAST OF THE AREA. AS FOR THE ARCTIC FRONT...IT WILL BE PUSHED THROUGH BY A 1035MB THAT THE GFS/ECMWF SHOW BEING CENTERED OVER MN BY FRIDAY MORNING. DEPENDING ON CLOUD COVER/SNOW COVER...THIS PATTERN WOULD GIVE US THE OPPORTUNITY TO GET LOWS BACK DOWN IN THE SINGLE DIGITS...WHICH IS EXACTLY WHAT THE ECMWF HAS ALL BUT SOUTH CENTRAL MN DOING FRIDAY MORNING. STUCK WITH A BLENDED FORECAST FOR NOW...WHICH KEPT LOWS FRIDAY MORNING UP IN THE TEENS AND 20S...BUT WE MAY NEED TO TAKE A GOOD 10 DEGREES OFF OF THAT DEPENDING ON HOW THINGS UNFOLD. FOR THE WEEKEND...THE CLIPPER THE ECMWF HAD BEEN SHOWING SLIDING ACROSS THE AREA FRIDAY NIGHT IS NOW GONE...SIMILAR TO WHAT THE GFS HAS BEEN GOING WITH. FOR CONTINUITY PURPOSES LEFT SOME SLIGHT CHANCE POPS IN FOR FRIDAY NIGHT ACROSS THE ERN HALF OF THE AREA...BUT THOSE COULD PROBABLY BE REMOVED IF THE ECMWF COMES IN DRY AGAIN WITH ITS 22.12 RUN. THE ECMWF/GFS ARE IN GOOD AGREEMENT THIS FAR OUT ON THE NEXT SYSTEM THOUGH COMING ACROSS THE AREA SAT NIGHT/SUNDAY. BOTH MODELS SHOW A STRONG CLIPPER DIVING SOUTHEAST ACROSS NRN MN AND NRN WI. THIS WOULD PLACE THE MPX AREA INTO ITS WARM SECTOR SATURDAY/SATURDAY NIGHT BEFORE GETTING ANOTHER PUSH OF COLD AIR TO END OF THE WEEKEND. THIS TRACK AT THE MOMENT WOULD KEEP ANY ACCUMULATING SNOW WITH THIS SYSTEM WELL NORTHEAST OF THE MPX AREA. AT THE VERY LEAST...THIS SYSTEM WILL BRING RATHER BLUSTERY WINDS BOTH AHEAD OF AND BEHIND ITS COLD FRONT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 655 AM CDT SUN MAR 22 2015 THE MAIN FORECAST CONCERN CONTINUES TO BE TIMING/PLACEMENT OF PRECIPITATION TODAY AND TONIGHT. DESPITE THE AMOUNT OF DRY LLVL AIR WITH THE NORTHEAST FLOW...WE ARE BEGINNING TO SEE SOME RADAR RETURNS REACHING THE GROUND ACROSS SOUTHWEST MN. LEANED TOWARD THE 22.10Z HRRR WHICH EXPANDS THE AREA OF SPOTTY SHOWERS NORTHEAST ACROSS THE AREA THIS MORNING...BUT REALLY BLOSSOMS THINGS DURING THE AFTERNOON AND EVENING AS THE STRONGER FORCING ARRIVES. HAVE THEREFORE FEATURED THE LOWEST CONDITIONS /IFR-LIFR/ BETWEEN 21Z AND 04Z...WHEN SNOW SHOULD BE MODERATE TO HEAVY. WINDS ALSO LOOK A BIG STRONGER THAN PREVIOUSLY EXPECTED...SO HAVE INCLUDED SOME GUSTS. KMSP... THE WINDOW FOR VFR CONDITIONS IS SHRINKING...WITH PRECIPITATION BEGINNING TO HIT THE GROUND OVER SOUTHWEST MN. EXPECT THIS AREA OF PRECIPITATION TO NEAR THE FIELD AROUND 17Z...WITH CIGS/VSBYS QUICKLY DECLINING ONCE THE SNOW BEGINS. THE WORST CONDITIONS /IFR-LIFR/ ARE LIKELY FROM 20Z SUNDAY AFTERNOON THROUGH LATE EVENING AS THE INTENSITY OF THE SNOW INCREASES...WITH WINDS VEERING TO EASTERLY AT 10-15 KTS AROUND 090 DEGREES. SNOW WILL DIMINISH OVERNIGHT...ENDING BY THE EARLY MORNING MONDAY. ACCUMULATIONS OF 3 TO 5 INCHES ARE EXPECTED AT KMSP...WITH 3/4 INCH RATE ACCUMULATIONS APPEARING POSSIBLE BETWEEN 21Z AND 02Z. /OUTLOOK FOR KMSP/ MON...MVFR. WINDS SE 5-10 KTS. TUE...MVFR/IFR WITH -RA LATE. WINDS SE 15G20 KTS. WED...MVFR/IFR WITH -RA/-SN. WINDS W 15G25 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER WEATHER ADVISORY FROM 11 AM THIS MORNING TO 1 AM CDT MONDAY FOR MNZ049-051-057>063-066>070-076>078-085. WI...WINTER WEATHER ADVISORY FROM 11 AM THIS MORNING TO 1 AM CDT MONDAY FOR WIZ023-024-026. && $$ SHORT TERM...LS LONG TERM...MPG AVIATION...LS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
700 AM EDT SUN MAR 22 2015 .SYNOPSIS...A WEAK COLD FRONT WILL MOVE ACROSS CENTRAL NC THIS MORNING...FOLLOWED BY THE PASSAGE OF A STRONGER COLD FRONT TONIGHT. A SERIES OF WEAK AREAS OF LOW PRESSURE WILL TRACK EAST ACROSS THE DEEP SOUTH AND OFF THE SOUTH ATLANTIC COAST THROUGH MONDAY NIGHT. HIGH PRESSURE WILL EXTEND INTO THE REGION FROM THE NORTHEAST ON TUESDAY AND WEDNESDAY BEFORE THE NEXT COLD FRONT APPROACHES THE REGION FROM THE WEST ON THURSDAY. && .NEAR TERM /SUNDAY THROUGH MONDAY/... AS OF 325 AM SUNDAY... A SOUTHERN STREAM SHORT WAVE TROUGH LOCATED OVER TX AND OK EARLY THIS MORNING WILL SHIFT EAST AND REACH THE SOUTH ATLANTIC COAST BY LATE MONDAY AFTERNOON. FURTHER ALOFT...A STRONG SUBTROPICAL JET WITH A MOISTURE CONNECTION FROM THE EASTERN PACIFIC WILL EXTEND ACROSS THE SOUTHEAST DURING THE PERIOD WITH SPEEDS AT TIMES IN EXCES OF 125KTS. AT THE SURFACE...A SERIES OF WEAK SURFACE LOWS WILL MOVE ACROSS THE NORTHERN GULF COAST AND INTO THE ATLANTIC NEAR THE FL/GA COAST. FINALLY...A SOUTHWARD ADVANCING COLD FRONT LOCATED ACROSS NORTHERN VA AT 06Z WILL DROP INTO CENTRAL NC LATER THIS MORNING WITH A SECONDARY A STRONGER FRONT PUSHING INTO NC LATE TONIGHT. TODAY WILL FEATURE MAINLY CLOUDY SKIES ACROSS CENTRAL NC ALTHOUGH THE CLOUDINESS WILL BE OF A MID AND HIGH NATURE THIS MORNING EVERYWHERE RESULTING IN A RELATIVELY BRIGHT OVERCAST. REGIONAL RADAR SHOWS AN AREA OF LIGHT RAIN EXTENDING ACROSS AL AND GA AND NOW CROSSING THE SAVANNAH RIVER INTO SC. THE NORTHERN EXTENT OF THIS PRECIPITATION IS VERY LIGHT AND FALLING FROM MID LEVEL CLOUDS. DETERMINISTIC NWP GUIDANCE HAS BEEN FAIRLY CONSISTENT IN DEPICTING A SHARP BOUNDARY BETWEEN THE RAIN SHIELD RAIN AND DRY WEATHER TO THE NORTH WITH THE BOUNDARY LIKELY SETTING UP JUST NORTH OF THE NORTH CAROLINA-SOUTH CAROLINA BORDER. GIVEN RADAR TRENDS AND HIGHER RESOLUTION GUIDANCE INCLUDING THE HRRR AND THE HI RES WINDOW RUNS...HAVE INCREASED POPS AND QPF AMOUNTS FOR THE SOUTHERN MOST ROW OF COUNTIES IN NC. STILL...CONFIDENCE IN HOW MUCH AND HOW FAR NORTH THE PRECIPITATION WILL FALL IS LIMITED BUT IT APPEARS THAT MEASURABLE RAIN TODAY WILL REMAIN SOUTH OF THE U.S. 64 CORRIDOR. EVEN WHERE THERE IS A GOOD CHANCE OF RAIN SUCH AS FAYETTEVILLE... GUIDANCE IS VARYING IN HOW MUCH. FOR EXAMPLE THE 21Z SREF 30-HOUR FORECAST FOR FAY NOTES 4 OF THE 21 MEMBERS PRODUCING MORE THAN AN INCH OF PRECIPITATION WHILE 6 MEMBERS HAVE LESS THAN 3 HUNDRETHS AND THE START TIME OF THE PRECIPITATION VARIES JUST AS WIDELY. EVEN WITH OVERCAST SKIES AND SOME SLIGHTLY COOLER AIR FILTERING IN FROM THE NORTHEAST...HIGHS TODAY SHOULD GENERALLY RANGE IN THE LOWER TO MID 60S WITH THE COOLEST TEMPS IN THE NORTHEAST WITH HIGHS AROUND 60 AND A FEW LOCATIONS ACROSS THE WESTERN PIEDMONT FLIRTING WITH THE UPPER 60S. THE WEAK WAVES OF LOWER PRESSURE WILL CONTINUE TO SKIRT BY TO OUR SOUTH TONIGHT AND MONDAY. A SECONDARY COLD FRONT WILL PUSH INTO NC FROM THE NORTHEAST LATE TONIGHT AND EARLY MONDAY WITH NOTABLY COOLER AN DRIER AIR. WIDESPREAD OVERCAST CONDITIONS ARE EXPECTED TONIGHT INTO MONDAY WITH SOME THINNING OF THE CLOUD COVER EXPECTED LATE IN THE DAY ACROSS THE NORTHERN AND WESTERN PIEDMONT. CHANCES OF LIGHT RAIN WILL CONTINUE ACROSS THE SOUTHEAST. LIGHT NORTHEAST AND EASTERLY WINDS WILL BECOME NORTHEAST AND INCREASE LATE TONIGHT AND MONDAY BEHIND THE FRONT WITH SOME GUSTS REACHING THE 15-20 MPH RANGE. LOWS TONIGHT WILL RANGE FROM AROUND 40 TO 45 WITH HIGHS ON MONDA IN THE LOWER 50S. -BLAES && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... AS OF 320 AM SUNDAY... MONDAY NIGHT THROUGH TUESDAY... S/W IN THE SOUTHERN STREAM WILL CONTINUE TO SHEAR OUT AS IT PROGRESSES EASTWARD ACROSS SOUTH CAROLINA. MEANWHILE A PARENT SFC HIGH OVER NEW ENGLAND WILL CONTINUE TO NOSE/BUILD SOUTHWARD INTO THE CAROLINAS. THIS SFC WEATHER SYSTEM WILL CONTINUE TO ADVECT A COOLER/DRIER LOW LEVEL AIR MASS INTO THE REGION. ANY PRECIP OVER THE FAR SOUTH-SE SECTIONS OF THE FORECAST AREA WILL GRADUALLY DIMINISH AS LIFT ASSOCIATED WITH THE S/W WEAKENS. MIN TEMPS MONDAY NIGHT MID-UPPER 30S. THE SURFACE PATTERN FOR TUESDAY WITH A PARENT HIGH CENTERED OVER NEW ENGLAND AND SLY AND/OR BACKING FLOW IN THE 850MB-700MB LAYER WIL SUPPORT A WEAK CLASSICAL COLD AIR DAMMING EVENT FOR TUESDAY. CONSIDERABLE CLOUDINESS AND A SFC NE WIND SHOULD LEAD TO AFTERNOON TEMPS 7-10 DEGREES BELOW NORMAL (AT LEAST). TUESDAY NIGHT...INCREASING SLY FLOW IN THE 925-850MB SHOULD CAUSE PATCHES OF DRIZZLE TO OCCUR ALONG WITH EXTENSIVE LOW CLOUDS. MIN TEMPS UPPER 30S-LOWER 40S. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 320 AM SUNDAY... WEDNESDAY THROUGH SATURDAY... UPPER AIR PATTERN WILL EVOLVE THIS PERIOD INTO A PATTERN SIMILAR TO THE LAST HALF OF TIS WINTER SEASON WITH A PRONOUNCED RIDGE IN THE WEST AND A TROUGH OVER THE EAST. THE LEAD S/W INITIATING THIS PATTERN EVOLUTION WILL CROSSING THE PLAINS STATES WEDNESDAY. CLOSER TO HOME...SFC RIDGE WILL DRIFT OFFSHORE IN RESPONSE TO THE APPROACHING S/W...WITH A SLY LOW LEVEL FLOW INCREASING ACROSS OUR REGION. THIS FLOW OVER THE COOL STABLE DOME OF AIR LEFTOVER FROM THE CAD EVENT TUESDAY SHOULD CAUSE EXTENSIVE CLOUDINESS WEDNESDAY MORNING ALONG WITH PATCHES OF DRIZZLE OR DENSE FOG. MODELS HINT AT SOME EXTENSION OF THE RIDGE PERSISTING OVER OUR REGION SO THE LOW CLOUDS MAY HOLD ON LONGER THAN PREDICTED BY THE MODELS WHICH MAY CAUSE HIGH TEMPS WEDNESDAY TO BE COOLER THAN FORECAST. HAVE LOWERED MAX TEMPS ABOUT A CATEGORY FROM THE PREVIOUS FORECAST AND THIS MAY NOT BE ENOUGH. THIS WILL NEED TO BE RE- EVALUATED WITH LATER MODEL RUNS. WITH THE INCREASING SLY FLOW WILL COME A THREAT FOR A FEW SHOWERS WEDNESDAY. HAVE INTRODUCED A SLIGHT CHANCE POP FOR WEDNESDAY. LEAD S/W WILL LIFT WELL NORTH OF OUR REGION THROUGH A SHEAR AXIS AND SFC FRONT WILL EXTEND SOUTHWARD INTO THE TN VALLEY THURSDAY MORNING...MOVING INTO THE CAROLINA PIEDMONT BY LATE THURSDAY- THURSDAY EVENING. 00Z GFS DEPICTS A SLIGHTLY UNSTABLE AIR MASS WITH SFC BASED CAPE VALUES 1000-1400 J/KG AND MUCAPE JUST SHY OF 1000 J/KG. BULK SHEAR INCREASES TO 35-45 KTS BY LATE IN THE DAY. THE CAPE VALUES MAY BE ACHIEVED IF ENOUGH HEATING OCCURS WHICH IS QUESTIONABLE AS CONSIDERABLE CLOUDINESS FROM RESIDUAL CAD MAY STILL BE AN ISSUE. WILL MAINTAIN CHANCE POPS FOR THURSDAY AFTERNOON- THURSDAY NIGHT ALONG WITH A MENTION OF THUNDER BASED ON THE ABOVE CONVECTIVE PARAMETERS. HIGH TEMPS THURSDAY COULD END UP BEING 3-5 DEGREES COOLER...BASED ON WHETHER CLOUDS/SHOWERS MORE EXTENSIVE THAN CURRENT THINKING. MILD WEDNESDAY NIGHT AHEAD OF THE FRONT WITH OVERNIGHT TEMPS IN THE MID-UPPER 50S. HIGHS THURSDAY LOWER 70S NW TO UPPER 70S SE. UNSETTLED WEATHER EXPECTED FRIDAY THROUGH EARLY SATURDAY AS A SERIES OF S/WS ALOFT DIG THE UPPER TROUGH OVER THE EASTERN U.S. WHILE FRONTAL PASSAGE EXPECTED THURSDAY NIGHT...COULD SEE POCKETS OF LIGHT RAIN TRAVERSE ACROSS THE REGION FRIDAY...FRIDAY NIGHT AND POSSIBLY SATURDAY ASSOCIATED WITH THE S/WS ALOFT. UPPER TROUGH OVERHEAD WILL LEAD TO A PERIOD OF BELOW NORMAL HIGH TEMPS...AVERAGING 10-15 DEGREES BELOW NORMAL. && .AVIATION /11Z SUNDAY THROUGH THURSDAY/... AS OF 700 AM SUNDAY... 24 HOUR TAF PERIOD...OUTSIDE OF A FEW PATCHES OF FOG THIS MORNING...VFR CONDITIONS ARE WIDESPREAD ACROSS CENTRAL NC THIS MORNING. HOWEVER...A SERIES OF WEAK AREAS OF LOW PRESSURE WILL HELP GENERATE A LARGE AREA OF LIGHT RAIN ACROSS THE DEEP SOUTH THROUGH MONDAY. THE MAJORITY OF THIS PRECIPITATION WILL FALL SOUTH OF THE KINT...KGSO...KRDU...AND KRWI TERMINALS WITH A RELATIVELY SHARP BOUNDARY BETWEEN RAIN AND NO RAIN LIKELY TO EXTEND ALONG AND JUST NORTH OF THE NORTH AND SOUTH CAROLINA BORDER. SOME OF THE RAIN WILL LIKELY REACH THE KFAY TERMINAL LATER THIS MORNING OR MORE LIKELY DURING THE AFTERNOON. CONFIDENCE REGARDING HOW MUCH AND HOW FAR NORTH THE PRECIPITATION WILL FALL IS LOW. AT LEAST INITIALLY...MUCH OF THE PRECIPITATION WILL FALL FROM MID LEVEL CLOUDS AND THE EXTENT OF CEILING REDUCTION AT KFAY IS UNCERTAIN BUT FEEL IT IS PROBABLE THAT AT LEAST A PERIOD OF MVFR CIGS AND VSBYS WILL OCCUR THIS EVENING. AFTER MIDNIGHT...LOW LEVEL MOISTURE WILL INCREASE AND MORE WIDESPREAD LOW CEILINGS AT 2500-3500 FEET ARE EXPECTED ACROSS ALL OF THE TERMINALS. CALM OR VERY LIGHT SOUTHWESTERLY WINDS EARLY THIS MORNING WILL BECOME NORTHEASTERLY AND INCREASINGLY GUSTY WITH THE PASSAGE OF A COLD FRONT THIS MORNING AND EARLY AFTERNOON. A BAND OF LOWER CLOUDS IS LIKELY TO BE ATTENDANT TO THE FRONT WITH IFR-MVFR CIGS. OUTLOOK... THE POTENTIAL FOR SOME LIGHT RAIN...MAINLY TO THE SOUTH OF KRDU AND KRWI CONTINUES LATE TONIGHT INTO MONDAY AFTERNOON. REDUCED CIGS ARE LIKELY TO PERSIST FROM MONDAY INTO TUESDAY MORNING. ADVERSE AVIATION CONDITIONS ARE LIKELY TO DEVELOP WEDNESDAY AND WEDNESDAY NIGHT WITH A MOIST SOUTHEAST FLOW PRODUCING LOW STRATUS AND SOME RAIN. ANOTHER ROUND OF ADVERSE AVIATION CONDITION ARE PROBABLE ON THURSDAY AS A COLD FRONT PRODUCES SCATTERED SHOWERS AS IT APPROACHES THE REGION. -BLAES && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BLAES NEAR TERM...BLAES SHORT TERM...WSS LONG TERM...WSS AVIATION...BLAES
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1053 AM CDT SUN MAR 22 2015 .UPDATE... ISSUED AT 1053 AM CDT SUN MAR 22 2015 MAIN UPDATE TO END THE FREEZING RAIN ADVISORY SOUTHWEST. ICY ROADS WILL LINGER THERE UNTIL TEMPERATURES RISE ABOVE FREEZING. ALSO INCREASED CHANCES OF LIGHT SNOW FAR SOUTHWEST FOR THE AFTERNOON HOURS. UPDATED HOURLY TEMPERATURE TRENDS. UPDATED FORECASTS WILL BE ISSUED SHORTLY. UPDATE ISSUED AT 940 AM CDT SUN MAR 22 2015 MAIN CONCERN IS PRECIPITATION TYPE ACROSS THE SOUTHWEST AND SOUTH CENTRAL. FEW OBSERVATION POINTS THIS AREA. RADAR ECHOES HAD EXPANDED FROM GRANT AND SIOUX COUNTY INTO EMMONS/LOGAN/MCINTOSH COUNTIES AND FEAR WAS THAT FREEZING RAIN MIGHT BE OCCURRING THERE. BRIGHT BAND OF REFLECTIVITY FROM HETTINGER TO SOUTHERN GRANT INTO SIOUX COUNTY INTO LOGAN/MCINTOSH...WITH RADAR SUGGESTING SLEET. REPORTS WEST IN SLOPE COUNTY AND HETTINGER WERE FREEZING RAIN...JUST RECENTLY GOT REPORTS OF SNOW NEAR THE CORNER OF EMMONS/LOGAN/MCINTOSH COUNTY. THUS APPEARS FREEZING RAIN WAS CHANGING TO SNOW EAST OF THE MISSOURI RIVER. MAIN BAND OF PRECIPITATION WAS MOVING SOUTH AND EAST...AND BY 11 AM CDT/10 AM MDT THE BULK OF PRECIPITATION SHOULD BE SOUTH AND EAST OF OUR AREA. THUS WILL KEEP THE FREEZING RAIN ADVISORY GOING FOR SOUTHWESTERN NORTH DAKOTA UNTIL SAID TIME. OTHER CHANGE WAS THAT SURFACE TEMPERATURES IN THE SOUTHWEST WERE NOT RISING AS QUICKLY AS FORECAST. HOWEVER EXPECT RISING TEMPERATURES TO COMMENCE WITHIN AN HOUR OR TWO AND BEGIN RISING INTO THE 40S BY LATE MORNING...AS WINDS IN THE FAR WEST BECOME SOUTH AND THEN TURN WEST BRINGING WARMER AIR INTO THE REGION. UPDATE ISSUED AT 705 AM CDT SUN MAR 22 2015 MADE ONLY MINOR ADJUSTMENTS TO THE FORECAST BY BLENDING IN CURRENT CONDITIONS. AREA RADARS STILL SHOW LIGHT PRECIPITATION MOVING ACROSS WESTERN AND CENTRAL NORTH DAKOTA...WITH THE LATEST MESO- SCALE MODELS FOCUSING MOST OF THEIR ATTENTION ON THE PRECIPITATION ACROSS SOUTHERN NORTH DAKOTA. THE FREEZING RAIN ADVISORY STILL LOOKS WELL PLACED AND WILL LEAVE AS IS. UPDATE ISSUED AT 512 AM CDT SUN MAR 22 2015 QUICK UPDATE TO ISSUE A FREEZING RAIN ADVISORY FOR THE SOUTHWEST CORNER. JUST HAD A REPORT OF ICY CONDITIONS NEAR HEBRON ON I94 WITH AN ACCIDENT AND SEMI TRUCKS STRUGGLING TO DRIVE UP HILLS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM CDT SUN MAR 22 2015 FORECAST HIGHLIGHTS AND CHALLENGES IN THE SHORT TERM PERIOD WILL BE THE THREAT FOR FREEZING PRECIPITATION ACROSS THE SOUTHWEST THIS MORNING...AND HOW PRECIPITATION EVOLVES EASTWARD. CURRENTLY...ACTIVE ZONAL FLOW ALOFT WITH A POTENT SHORT WAVE MOVING EAST INTO SOUTH CENTRAL CANADA AND ANOTHER MORE SUBTLE/EMBEDDED FEATURE MOVING EAST ACROSS NORTHERN WYOMING/SOUTHEASTERN MONTANA. ASSOCIATED SURFACE LOWS OVER SOUTHERN SASKATCHEWAN AND EASTERN WY/SOUTHWESTERN SD RESPECTIVELY. THE SOUTHERN MOST WAVE IS OUR MAIN CONCERN...GENERATING PRECIPITATION FROM SOUTHEASTERN MONTANA EAST TO ACROSS SOUTHWESTERN NORTH DAKOTA. THERMAL PROFILES AND SFC TEMPERATURES INDICATING LIGHT FREEZING RAIN IS LIKELY FALLING. MADE A FEW CALLS TO THE SOUTHWEST WHICH INDICATED NO IMPACTS AS SO FAR THE LIGHT FREEZING PRECIP IS ONLY TRACING OUT. A VERY DRY EASTERLY FLOW IS KEEPING THE BOUNDARY LAYER RATHER DRY FROM THE SURFACE UP TO 5-7K FT AGL...SO ANY MOISTURE REACHING THE GROUND SHOULD BE LIMITED. WILL MAINTAIN LIKELY POPS SOUTHWEST INTO SOUTH CENTRAL. HAVE A SPECIAL WEATHER STATEMENT OUT NOW FOR THE FREEZING RAIN POTENTIAL...AND WILL CONTINUE WITH THIS UNLESS WE HEAR OF MORE IMPACTS AND A FREEZING RAIN ADVISORY BECOMES NEEDED. MORE RADAR RETURNS ACROSS THE NORTH...BUT AGAIN WITH CLOUD BASES AT ROUGHLY 8-10K AGL...ANTICIPATE LITTLE IS REACHING THE GROUND SO WILL KEEP POPS BELOW LIKELY THERE. MODELS HAVING A HARD TIME THIS MORNING WITH EACH RUN OF THE HRRR AND NAM MODELS DIFFERENT. BASICALLY WENT WITH A BLEND WHICH FOLLOWS THE 00Z ECMWF AND LATEST 06Z NAM RATHER WELL. THIS CONFINES HIGHER POPS THIS MORNING TO MY SOUTHERN COUNTIES...ALONG TO SOUTH OF INTERSTATE 94. MAIN THREAT FOR FREEZING RAIN WILL REMAIN WEST OF THE MISSOURI RIVER ACROSS MY SOUTHWEST THROUGH MID MORNING...WITH THERMAL PROFILES SUGGESTING ALL SNOW TO THE EAST. SURFACE FRONTAL BOUNDARY MOMENTARILY STALLS ACROSS THE WEST THIS AFTERNOON...WITH A WESTERLY WIND TO THE WEST AND SOUTHERLY WIND TO THE EAST. NAM AND RAP ARE INDICATING POSSIBLE STRATUS DEVELOPMENT ALONG TO EAST OF THE BOUNDARY LATER TODAY INTO THIS EVENING AS THE SOUTH/SOUTHEASTERLY FLOW TRANSPORTS MOISTURE NORTH. THUS WILL KEEP SKY COVER ELEVATED ABOVE MOSTLY SUNNY/MOSTLY CLEAR. CONFIDENCE NOT HIGH WITH THIS PLAYING OUT WITH MODELS STRUGGLING THE PAST FEW RUNS. AFOREMENTIONED STRONG SHORT WAVE CUTTING EAST ACROSS SOUTH CENTRAL CANADA WILL TURN SOUTHEAST AND MOVE INTO FAR NORTHEASTERN ND/NORTHERN MINNESOTA THIS SUNDAY NIGHT. PRECIPITATION IN THE FORM OF SNOW MAY GRAZE MY FAR NORTHEAST SO WILL MAINTAIN A LOW POP THERE TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 414 AM CDT SUN MAR 22 2015 THE PRIMARY CONCERN IN THE LONG TERM PERIOD WILL BE THE POTENT STORM MONDAY NIGHT INTO TUESDAY. THE LATEST MODEL SUITE CONTINUES TO ADVERTISE A POTENT STORM SYSTEM ACROSS THE NORTHERN PLAINS MONDAY NIGHT INTO TUESDAY. DETAILS REGARDING THE EXACT TRACK OF THE SYSTEM REMAIN ELUSIVE WITH THE 00Z GFS AND ECMWF STILL SHOWING DIFFERENCES...AND LARGE SPREAD INDICATED BY THE GEFS. THE ECMWF AND GFS BOTH SUGGEST TWO SURFACE LOWS WILL DEVELOP...HOWEVER THEY DIFFER ON THE PROGRESSION OF THE NORTHERN MOST LOW. THE ECMWF KEEPS THE LOWS SEPARATE WITH ONE TRACKING INTO CANADA...WHILE THE GFS MERGES THE LOWS IN MINNESOTA / WISCONSIN. HAVE AGAIN GONE WITH A BLENDED MODEL SOLUTION DUE TO THE UNCERTAINTY. THIS MAINTAINS SOME CONSISTENCY IN THE FORECAST WITH WARM AIR AND RAIN EXPECTED ACROSS MUCH OF CENTRAL AND WESTERN NORTH DAKOTA DURING THE MORNING AND AFTERNOON TUESDAY. THE EXCEPTION COULD BE THE FAR NORTH AND WEST WHERE COLDER AIR MAY FAVOR SNOW. COLD AIR ARRIVES BEHIND THE LOW TUESDAY NIGHT...WHICH SUPPORTS A THERMAL PROFILE TRANSITIONING TO SNOW ACROSS THE FORECAST AREA. CONFIDENCE IN PRECIPITATION AND / OR SNOW AMOUNTS REMAINS LOW DUE TO THE LARGE DIFFERENCES IN MODEL SOLUTIONS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 705 AM CDT SUN MAR 22 2015 FREEZING RAIN EXPECTED THROUGH 12-14Z FOR KDIK...ALL SNOW EAST FOR KMOT-KBIS-KJMS WITH NO VISIBILITY RESTRICTIONS EXPECTED. IFR CONDITIONS POSSIBLE FOR KBIS-KJMS IF SNOW DEVELOPS MORE THAN EXPECTED LATER THIS MORNING. MODELS STILL INDICATE A CORRIDOR OF LOW STRATUS DEVELOPING DURING THE AFTERNOON INTO SUNDAY NIGHT CENTRAL IMPACTING KBIS-KMOT-KJMS. && .BIS WATCHES/WARNINGS/ADVISORIES... FREEZING RAIN ADVISORY UNTIL 11 AM CDT /10 AM MDT/ THIS MORNING FOR NDZ033-034-040>045. && $$ UPDATE...JV SHORT TERM...NH LONG TERM...CK AVIATION...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1001 AM CDT SUN MAR 22 2015 .UPDATE... ISSUED AT 1001 AM CDT SUN MAR 22 2015 BAND OF PRECIP CONTINUES TO MOVE EASTWARD TOWARDS OUR SOUTHWESTERN COUNTIES. HOWEVER...WEB CAMS NEAR WISHEK WHICH HAS HAD RADAR RETURNS MOVING OVERHEAD FOR THE LAST FEW HOURS SHOW THAT NOT MUCH IS REACHING THE GROUND SO FAR. MODEL SOUNDINGS CONTINUE TO SHOW A DRY LAYER NEAR THE SFC WHICH DOES NOT REALLY SATURATE UNTIL WELL INTO THE AFTERNOON HOURS. CONTINUED TO KEEP SOME LIKELY POPS IN THE FAR SOUTHERN COUNTIES FOR THIS AFTERNOON AS WE WILL NOT SEE MUCH BEFORE THEN...BUT WILL HAVE TO WATCH TO SEE HOW THE BATTLE BETWEEN DRY AIR AND FRONTOGENESIS UNFOLDS AND MAKE ADJUSTMENTS AS NEEDED. UPDATE ISSUED AT 650 AM CDT SUN MAR 22 2015 BAND OF PRECIP IS SETTING UP ACROSS SOUTHERN NORTH DAKOTA...AND LATEST HI-RES GUIDANCE INDICATES THIS BAND WILL AFFECT THE FAR SOUTHERN FA BY LATER THIS MORNING AND INTO THE AFTERNOON HOURS. STRONGEST MESOSCALE FORCING WILL BE SOUTH OF THIS AREA...BUT CURRENT INDICATIONS SUGGEST AND INCH OR TWO OF SNOW MAY OCCUR TODAY ACROSS THIS AREA. TO THE NORTH...GIVEN THE DRY LOW LEVEL AIRMASS IN PLACE AND WEAKER FORCING WENT WITH A DRY FORECAST (EXCEPT THE CANDO AREA FOR THIS MORNING WHERE RADAR INDICATES A STRONGER AREA OF PRECIP MAY PROVIDE FLURRIES OR VERY LIGHT SNOW FOR A BRIEF TIME). && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 330 AM CDT SUN MAR 22 2015 SNOW CHANCES AND AMOUNTS WILL BE THE CHALLENGE. 00Z MODELS IN DECENT AGREEMENT...ALTHOUGH THERE ARE SOME DIFFERENCES TODAY. RIDGING REMAINS IN PLACE ACROSS THE REGION WITH DRY LOW LEVEL EASTERLY FLOW. MODEL TRENDS INDICATE LESS INTERACTION BETWEEN NORTHERN AND SOUTHERN UPPER WAVES...LEADING TO FAR LESS QPF ACROSS THE WESTERN FA TODAY. IN FACT...THE LATEST HRRR AND RAP GUIDANCE INDICATES THAT QPF WILL REMAIN OUTSIDE OF THE FA WITH STRONGER RIDGING/MORE DRY AIR. TRENDED THE FORECAST IN THIS DIRECTION...WITH MAYBE AN INCH OR TWO OF SNOW ACROSS THE FAR SOUTHERN FA. WILL CONTINUE TO MONITOR TRENDS AND MAY EVENTUALLY REMOVE ALL POPS FOR TODAY. WITH THIS...MODELS ARE TRENDING WARMER TODAY (THINNER CLOUD COVER)...AND FOLLOWED THIS TREND IN THE FORECAST. TONIGHT...THE NORTHERN UPPER WAVE IS QUITE STRONG...AND MODELS HAVE BEEN CONSISTENT SPREADING SNOW INTO PARTS OF THE NORTHERN FA (WITH AN INCH OR TWO POSSIBLE). MONDAY...REGION WILL BE BETWEEN SYSTEMS ALONG WITH WARM AIR ADVECTION AHEAD OF THE NEXT SYSTEM. SHOULD BE A RELATIVELY QUIET DAY WITH MAX TEMPS APPROACHING OR INTO THE 40S. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAR 22 2015 MONDAY NIGHT-TUESDAY NIGHT...STRONGER SYSTEM WILL AFFECT THE REGION...MOST LIKELY LATER TUESDAY INTO TUESDAY NIGHT. CONFIDENCE IS HIGH THAT SOMETHING IS GOING TO OCCUR...ALTHOUGH MODELS ARE ALL OVER THE PLACE WITH DETAILS SO EXACTLY WHAT OCCURS IS HIGHLY QUESTIONABLE. GENERALLY...THE REGION WILL BE WITHIN AN INVERTED TROUGH WITH RAIN EVENTUALLY CHANGING TO SNOW. SOME MODELS ARE INDICATING OVER A FOOT OF SNOW...WITH OTHERS FAR LESS (OR ALMOST NOTHING). MUCH WILL DEPEND ON HOW THE SYSTEM EVOLVES...AND WHEN/WHERE THE SOUTHERN SFC LOW STRENGTHENS (WHICH WILL INFLUENCE THE STRENGTH OF THE INVERTED TROUGH AND THUS QPF AMOUNTS). FOR NOW...THE BEST THING TO SAY IS RAIN CHANGING TO SNOW WITH SOME ACCUMULATIONS POSSIBLE. WEDNESDAY-SATURDAY...THE BACKSIDE OF THE FULLY DEVELOPED CLOSED- LOW SYSTEM OVER WISCONSIN AND MOVING EASTWARD WILL BRING AN END TO THE PRECIPITATION OVER WEST-CENTRAL MINNESOTA WITH THE NORTHERLY WINDS ADVECTING IN SOME COOLER DAYTIME TEMPERATURES IN THE 30S AND LOWS IN THE TEENS FOR WEDNESDAY. A SURFACE HIGH PRESSURE SYSTEM WILL BE IN PLACE OVER THE AREA BY THURSDAY AHEAD OF A BUILDING UPPER-AIR RIDGE ON THE WEST COAST. THAT HIGH WILL BE SHIFTING TO THE EAST WITH SOME SOUTHERLY WINDS ON ITS BACKSIDE BRINGING IN SOME WARMER AIR FOR FRIDAY AND SATURDAY. HOWEVER...AN EMBEDDED UPPER-AIR SHORT WAVE EMBEDDED IN THE NORTHWEST FLOW FROM WESTERN RIDGE WILL BRING GOOD CHANCES FOR WEEKEND PRECIPITATION AS ANOTHER SURFACE LOW SPINS UP TO TRAVERSE THE REGION OVER THE WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 650 AM CDT SUN MAR 22 2015 DRY LOW LEVEL AIRMASS WILL REMAIN IN PLACE TODAY...LEADING TO VFR CIGS. ANTICIPATE THESE CONDITIONS WILL CONTINUE INTO THE OVERNIGHT HOURS...WITH ANY -SN CHANCES REMAINING AWAY FROM THE TAF SITES (TO THE SOUTH TODAY...AND TO THE NORTH TONIGHT). && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JR SHORT TERM...TG LONG TERM...TG/LUKES AVIATION...TG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
940 AM CDT SUN MAR 22 2015 .UPDATE... ISSUED AT 940 AM CDT SUN MAR 22 2015 MAIN CONCERN IS PRECIPITATION TYPE ACROSS THE SOUTHWEST AND SOUTH CENTRAL. FEW OBSERVATION POINTS THIS AREA. RADAR ECHOES HAD EXPANDED FROM GRANT AND SIOUX COUNTY INTO EMMONS/LOGAN/MCINTOSH COUNTIES AND FEAR WAS THAT FREEZING RAIN MIGHT BE OCCURRING THERE. BRIGHT BAND OF REFLECTIVITY FROM HETTINGER TO SOUTHERN GRANT INTO SIOUX COUNTY INTO LOGAN/MCINTOSH...WITH RADAR SUGGESTING SLEET. REPORTS WEST IN SLOPE COUNTY AND HETTINGER WERE FREEZING RAIN...JUST RECENTLY GOT REPORTS OF SNOW NEAR THE CORNER OF EMMONS/LOGAN/MCINTOSH COUNTY. THUS APPEARS FREEZING RAIN WAS CHANGING TO SNOW EAST OF THE MISSOURI RIVER. MAIN BAND OF PRECIPITATION WAS MOVING SOUTH AND EAST...AND BY 11 AM CDT/10 AM MDT THE BULK OF PRECIPITATION SHOULD BE SOUTH AND EAST OF OUR AREA. THUS WILL KEEP THE FREEZING RAIN ADVISORY GOING FOR SOUTHWESTERN NORTH DAKOTA UNTIL SAID TIME. OTHER CHANGE WAS THAT SURFACE TEMPERATURES IN THE SOUTHWEST WERE NOT RISING AS QUICKLY AS FORECAST. HOWEVER EXPECT RISING TEMPERATURES TO COMMENCE WITHIN AN HOUR OR TWO AND BEGIN RISING INTO THE 40S BY LATE MORNING...AS WINDS IN THE FAR WEST BECOME SOUTH AND THEN TURN WEST BRINGING WARMER AIR INTO THE REGION. UPDATE ISSUED AT 705 AM CDT SUN MAR 22 2015 MADE ONLY MINOR ADJUSTMENTS TO THE FORECAST BY BLENDING IN CURRENT CONDITIONS. AREA RADARS STILL SHOW LIGHT PRECIPITATION MOVING ACROSS WESTERN AND CENTRAL NORTH DAKOTA...WITH THE LATEST MESO- SCALE MODELS FOCUSING MOST OF THEIR ATTENTION ON THE PRECIPITATION ACROSS SOUTHERN NORTH DAKOTA. THE FREEZING RAIN ADVISORY STILL LOOKS WELL PLACED AND WILL LEAVE AS IS. UPDATE ISSUED AT 512 AM CDT SUN MAR 22 2015 QUICK UPDATE TO ISSUE A FREEZING RAIN ADVISORY FOR THE SOUTHWEST CORNER. JUST HAD A REPORT OF ICY CONDITIONS NEAR HEBRON ON I94 WITH AN ACCIDENT AND SEMI TRUCKS STRUGGLING TO DRIVE UP HILLS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM CDT SUN MAR 22 2015 FORECAST HIGHLIGHTS AND CHALLENGES IN THE SHORT TERM PERIOD WILL BE THE THREAT FOR FREEZING PRECIPITATION ACROSS THE SOUTHWEST THIS MORNING...AND HOW PRECIPITATION EVOLVES EASTWARD. CURRENTLY...ACTIVE ZONAL FLOW ALOFT WITH A POTENT SHORT WAVE MOVING EAST INTO SOUTH CENTRAL CANADA AND ANOTHER MORE SUBTLE/EMBEDDED FEATURE MOVING EAST ACROSS NORTHERN WYOMING/SOUTHEASTERN MONTANA. ASSOCIATED SURFACE LOWS OVER SOUTHERN SASKATCHEWAN AND EASTERN WY/SOUTHWESTERN SD RESPECTIVELY. THE SOUTHERN MOST WAVE IS OUR MAIN CONCERN...GENERATING PRECIPITATION FROM SOUTHEASTERN MONTANA EAST TO ACROSS SOUTHWESTERN NORTH DAKOTA. THERMAL PROFILES AND SFC TEMPERATURES INDICATING LIGHT FREEZING RAIN IS LIKELY FALLING. MADE A FEW CALLS TO THE SOUTHWEST WHICH INDICATED NO IMPACTS AS SO FAR THE LIGHT FREEZING PRECIP IS ONLY TRACING OUT. A VERY DRY EASTERLY FLOW IS KEEPING THE BOUNDARY LAYER RATHER DRY FROM THE SURFACE UP TO 5-7K FT AGL...SO ANY MOISTURE REACHING THE GROUND SHOULD BE LIMITED. WILL MAINTAIN LIKELY POPS SOUTHWEST INTO SOUTH CENTRAL. HAVE A SPECIAL WEATHER STATEMENT OUT NOW FOR THE FREEZING RAIN POTENTIAL...AND WILL CONTINUE WITH THIS UNLESS WE HEAR OF MORE IMPACTS AND A FREEZING RAIN ADVISORY BECOMES NEEDED. MORE RADAR RETURNS ACROSS THE NORTH...BUT AGAIN WITH CLOUD BASES AT ROUGHLY 8-10K AGL...ANTICIPATE LITTLE IS REACHING THE GROUND SO WILL KEEP POPS BELOW LIKELY THERE. MODELS HAVING A HARD TIME THIS MORNING WITH EACH RUN OF THE HRRR AND NAM MODELS DIFFERENT. BASICALLY WENT WITH A BLEND WHICH FOLLOWS THE 00Z ECMWF AND LATEST 06Z NAM RATHER WELL. THIS CONFINES HIGHER POPS THIS MORNING TO MY SOUTHERN COUNTIES...ALONG TO SOUTH OF INTERSTATE 94. MAIN THREAT FOR FREEZING RAIN WILL REMAIN WEST OF THE MISSOURI RIVER ACROSS MY SOUTHWEST THROUGH MID MORNING...WITH THERMAL PROFILES SUGGESTING ALL SNOW TO THE EAST. SURFACE FRONTAL BOUNDARY MOMENTARILY STALLS ACROSS THE WEST THIS AFTERNOON...WITH A WESTERLY WIND TO THE WEST AND SOUTHERLY WIND TO THE EAST. NAM AND RAP ARE INDICATING POSSIBLE STRATUS DEVELOPMENT ALONG TO EAST OF THE BOUNDARY LATER TODAY INTO THIS EVENING AS THE SOUTH/SOUTHEASTERLY FLOW TRANSPORTS MOISTURE NORTH. THUS WILL KEEP SKY COVER ELEVATED ABOVE MOSTLY SUNNY/MOSTLY CLEAR. CONFIDENCE NOT HIGH WITH THIS PLAYING OUT WITH MODELS STRUGGLING THE PAST FEW RUNS. AFOREMENTIONED STRONG SHORT WAVE CUTTING EAST ACROSS SOUTH CENTRAL CANADA WILL TURN SOUTHEAST AND MOVE INTO FAR NORTHEASTERN ND/NORTHERN MINNESOTA THIS SUNDAY NIGHT. PRECIPITATION IN THE FORM OF SNOW MAY GRAZE MY FAR NORTHEAST SO WILL MAINTAIN A LOW POP THERE TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 414 AM CDT SUN MAR 22 2015 THE PRIMARY CONCERN IN THE LONG TERM PERIOD WILL BE THE POTENT STORM MONDAY NIGHT INTO TUESDAY. THE LATEST MODEL SUITE CONTINUES TO ADVERTISE A POTENT STORM SYSTEM ACROSS THE NORTHERN PLAINS MONDAY NIGHT INTO TUESDAY. DETAILS REGARDING THE EXACT TRACK OF THE SYSTEM REMAIN ELUSIVE WITH THE 00Z GFS AND ECMWF STILL SHOWING DIFFERENCES...AND LARGE SPREAD INDICATED BY THE GEFS. THE ECMWF AND GFS BOTH SUGGEST TWO SURFACE LOWS WILL DEVELOP...HOWEVER THEY DIFFER ON THE PROGRESSION OF THE NORTHERN MOST LOW. THE ECMWF KEEPS THE LOWS SEPARATE WITH ONE TRACKING INTO CANADA...WHILE THE GFS MERGES THE LOWS IN MINNESOTA / WISCONSIN. HAVE AGAIN GONE WITH A BLENDED MODEL SOLUTION DUE TO THE UNCERTAINTY. THIS MAINTAINS SOME CONSISTENCY IN THE FORECAST WITH WARM AIR AND RAIN EXPECTED ACROSS MUCH OF CENTRAL AND WESTERN NORTH DAKOTA DURING THE MORNING AND AFTERNOON TUESDAY. THE EXCEPTION COULD BE THE FAR NORTH AND WEST WHERE COLDER AIR MAY FAVOR SNOW. COLD AIR ARRIVES BEHIND THE LOW TUESDAY NIGHT...WHICH SUPPORTS A THERMAL PROFILE TRANSITIONING TO SNOW ACROSS THE FORECAST AREA. CONFIDENCE IN PRECIPITATION AND / OR SNOW AMOUNTS REMAINS LOW DUE TO THE LARGE DIFFERENCES IN MODEL SOLUTIONS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 705 AM CDT SUN MAR 22 2015 FREEZING RAIN EXPECTED THROUGH 12-14Z FOR KDIK...ALL SNOW EAST FOR KMOT-KBIS-KJMS WITH NO VISIBILITY RESTRICTIONS EXPECTED. IFR CONDITIONS POSSIBLE FOR KBIS-KJMS IF SNOW DEVELOPS MORE THAN EXPECTED LATER THIS MORNING. MODELS STILL INDICATE A CORRIDOR OF LOW STRATUS DEVELOPING DURING THE AFTERNOON INTO SUNDAY NIGHT CENTRAL IMPACTING KBIS-KMOT-KJMS. && .BIS WATCHES/WARNINGS/ADVISORIES... FREEZING RAIN ADVISORY UNTIL 11 AM CDT /10 AM MDT/ THIS MORNING FOR NDZ033-034-040>045. && $$ UPDATE...JV SHORT TERM...NH LONG TERM...CK AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
708 AM CDT SUN MAR 22 2015 .UPDATE... ISSUED AT 705 AM CDT SUN MAR 22 2015 MADE ONLY MINOR ADJUSTMENTS TO THE FORECAST BY BLENDING IN CURRENT CONDITIONS. AREA RADARS STILL SHOW LIGHT PRECIPITATION MOVING ACROSS WESTERN AND CENTRAL NORTH DAKOTA...WITH THE LATEST MESO- SCALE MODELS FOCUSING MOST OF THEIR ATTENTION ON THE PRECIPITATION ACROSS SOUTHERN NORTH DAKOTA. THE FREEZING RAIN ADVISORY STILL LOOKS WELL PLACED AND WILL LEAVE AS IS. UPDATE ISSUED AT 512 AM CDT SUN MAR 22 2015 QUICK UPDATE TO ISSUE A FREEZING RAIN ADVISORY FOR THE SOUTHWEST CORNER. JUST HAD A REPORT OF ICY CONDITIONS NEAR HEBRON ON I94 WITH AN ACCIDENT AND SEMI TRUCKS STRUGGLING TO DRIVE UP HILLS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM CDT SUN MAR 22 2015 FORECAST HIGHLIGHTS AND CHALLENGES IN THE SHORT TERM PERIOD WILL BE THE THREAT FOR FREEZING PRECIPITATION ACROSS THE SOUTHWEST THIS MORNING...AND HOW PRECIPITATION EVOLVES EASTWARD. CURRENTLY...ACTIVE ZONAL FLOW ALOFT WITH A POTENT SHORT WAVE MOVING EAST INTO SOUTH CENTRAL CANADA AND ANOTHER MORE SUBTLE/EMBEDDED FEATURE MOVING EAST ACROSS NORTHERN WYOMING/SOUTHEASTERN MONTANA. ASSOCIATED SURFACE LOWS OVER SOUTHERN SASKATCHEWAN AND EASTERN WY/SOUTHWESTERN SD RESPECTIVELY. THE SOUTHERN MOST WAVE IS OUR MAIN CONCERN...GENERATING PRECIPITATION FROM SOUTHEASTERN MONTANA EAST TO ACROSS SOUTHWESTERN NORTH DAKOTA. THERMAL PROFILES AND SFC TEMPERATURES INDICATING LIGHT FREEZING RAIN IS LIKELY FALLING. MADE A FEW CALLS TO THE SOUTHWEST WHICH INDICATED NO IMPACTS AS SO FAR THE LIGHT FREEZING PRECIP IS ONLY TRACING OUT. A VERY DRY EASTERLY FLOW IS KEEPING THE BOUNDARY LAYER RATHER DRY FROM THE SURFACE UP TO 5-7K FT AGL...SO ANY MOISTURE REACHING THE GROUND SHOULD BE LIMITED. WILL MAINTAIN LIKELY POPS SOUTHWEST INTO SOUTH CENTRAL. HAVE A SPECIAL WEATHER STATEMENT OUT NOW FOR THE FREEZING RAIN POTENTIAL...AND WILL CONTINUE WITH THIS UNLESS WE HEAR OF MORE IMPACTS AND A FREEZING RAIN ADVISORY BECOMES NEEDED. MORE RADAR RETURNS ACROSS THE NORTH...BUT AGAIN WITH CLOUD BASES AT ROUGHLY 8-10K AGL...ANTICIPATE LITTLE IS REACHING THE GROUND SO WILL KEEP POPS BELOW LIKELY THERE. MODELS HAVING A HARD TIME THIS MORNING WITH EACH RUN OF THE HRRR AND NAM MODELS DIFFERENT. BASICALLY WENT WITH A BLEND WHICH FOLLOWS THE 00Z ECMWF AND LATEST 06Z NAM RATHER WELL. THIS CONFINES HIGHER POPS THIS MORNING TO MY SOUTHERN COUNTIES...ALONG TO SOUTH OF INTERSTATE 94. MAIN THREAT FOR FREEZING RAIN WILL REMAIN WEST OF THE MISSOURI RIVER ACROSS MY SOUTHWEST THROUGH MID MORNING...WITH THERMAL PROFILES SUGGESTING ALL SNOW TO THE EAST. SURFACE FRONTAL BOUNDARY MOMENTARILY STALLS ACROSS THE WEST THIS AFTERNOON...WITH A WESTERLY WIND TO THE WEST AND SOUTHERLY WIND TO THE EAST. NAM AND RAP ARE INDICATING POSSIBLE STRATUS DEVELOPMENT ALONG TO EAST OF THE BOUNDARY LATER TODAY INTO THIS EVENING AS THE SOUTH/SOUTHEASTERLY FLOW TRANSPORTS MOISTURE NORTH. THUS WILL KEEP SKY COVER ELEVATED ABOVE MOSTLY SUNNY/MOSTLY CLEAR. CONFIDENCE NOT HIGH WITH THIS PLAYING OUT WITH MODELS STRUGGLING THE PAST FEW RUNS. AFOREMENTIONED STRONG SHORT WAVE CUTTING EAST ACROSS SOUTH CENTRAL CANADA WILL TURN SOUTHEAST AND MOVE INTO FAR NORTHEASTERN ND/NORTHERN MINNESOTA THIS SUNDAY NIGHT. PRECIPITATION IN THE FORM OF SNOW MAY GRAZE MY FAR NORTHEAST SO WILL MAINTAIN A LOW POP THERE TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 414 AM CDT SUN MAR 22 2015 THE PRIMARY CONCERN IN THE LONG TERM PERIOD WILL BE THE POTENT STORM MONDAY NIGHT INTO TUESDAY. THE LATEST MODEL SUITE CONTINUES TO ADVERTISE A POTENT STORM SYSTEM ACROSS THE NORTHERN PLAINS MONDAY NIGHT INTO TUESDAY. DETAILS REGARDING THE EXACT TRACK OF THE SYSTEM REMAIN ELUSIVE WITH THE 00Z GFS AND ECMWF STILL SHOWING DIFFERENCES...AND LARGE SPREAD INDICATED BY THE GEFS. THE ECMWF AND GFS BOTH SUGGEST TWO SURFACE LOWS WILL DEVELOP...HOWEVER THEY DIFFER ON THE PROGRESSION OF THE NORTHERN MOST LOW. THE ECMWF KEEPS THE LOWS SEPARATE WITH ONE TRACKING INTO CANADA...WHILE THE GFS MERGES THE LOWS IN MINNESOTA / WISCONSIN. HAVE AGAIN GONE WITH A BLENDED MODEL SOLUTION DUE TO THE UNCERTAINTY. THIS MAINTAINS SOME CONSISTENCY IN THE FORECAST WITH WARM AIR AND RAIN EXPECTED ACROSS MUCH OF CENTRAL AND WESTERN NORTH DAKOTA DURING THE MORNING AND AFTERNOON TUESDAY. THE EXCEPTION COULD BE THE FAR NORTH AND WEST WHERE COLDER AIR MAY FAVOR SNOW. COLD AIR ARRIVES BEHIND THE LOW TUESDAY NIGHT...WHICH SUPPORTS A THERMAL PROFILE TRANSITIONING TO SNOW ACROSS THE FORECAST AREA. CONFIDENCE IN PRECIPITATION AND / OR SNOW AMOUNTS REMAINS LOW DUE TO THE LARGE DIFFERENCES IN MODEL SOLUTIONS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 705 AM CDT SUN MAR 22 2015 FREEZING RAIN EXPECTED THROUGH 12-14Z FOR KDIK...ALL SNOW EAST FOR KMOT-KBIS-KJMS WITH NO VISIBILITY RESTRICTIONS EXPECTED. IFR CONDITIONS POSSIBLE FOR KBIS-KJMS IF SNOW DEVELOPS MORE THAN EXPECTED LATER THIS MORNING. MODELS STILL INDICATE A CORRIDOR OF LOW STRATUS DEVELOPING DURING THE AFTERNOON INTO SUNDAY NIGHT CENTRAL IMPACTING KBIS-KMOT-KJMS. && .BIS WATCHES/WARNINGS/ADVISORIES... FREEZING RAIN ADVISORY UNTIL 11 AM CDT /10 AM MDT/ THIS MORNING FOR NDZ033-034-040>045. && $$ UPDATE...CK SHORT TERM...NH LONG TERM...CK AVIATION...NH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
650 AM CDT SUN MAR 22 2015 .UPDATE... ISSUED AT 650 AM CDT SUN MAR 22 2015 BAND OF PRECIP IS SETTING UP ACROSS SOUTHERN NORTH DAKOTA...AND LATEST HI-RES GUIDANCE INDICATES THIS BAND WILL AFFECT THE FAR SOUTHERN FA BY LATER THIS MORNING AND INTO THE AFTERNOON HOURS. STRONGEST MESOSCALE FORCING WILL BE SOUTH OF THIS AREA...BUT CURRENT INDICATIONS SUGGEST AND INCH OR TWO OF SNOW MAY OCCUR TODAY ACROSS THIS AREA. TO THE NORTH...GIVEN THE DRY LOW LEVEL AIRMASS IN PLACE AND WEAKER FORCING WENT WITH A DRY FORECAST (EXCEPT THE CANDO AREA FOR THIS MORNING WHERE RADAR INDICATES A STRONGER AREA OF PRECIP MAY PROVIDE FLURRIES OR VERY LIGHT SNOW FOR A BRIEF TIME). && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 330 AM CDT SUN MAR 22 2015 SNOW CHANCES AND AMOUNTS WILL BE THE CHALLENGE. 00Z MODELS IN DECENT AGREEMENT...ALTHOUGH THERE ARE SOME DIFFERENCES TODAY. RIDGING REMAINS IN PLACE ACROSS THE REGION WITH DRY LOW LEVEL EASTERLY FLOW. MODEL TRENDS INDICATE LESS INTERACTION BETWEEN NORTHERN AND SOUTHERN UPPER WAVES...LEADING TO FAR LESS QPF ACROSS THE WESTERN FA TODAY. IN FACT...THE LATEST HRRR AND RAP GUIDANCE INDICATES THAT QPF WILL REMAIN OUTSIDE OF THE FA WITH STRONGER RIDGING/MORE DRY AIR. TRENDED THE FORECAST IN THIS DIRECTION...WITH MAYBE AN INCH OR TWO OF SNOW ACROSS THE FAR SOUTHERN FA. WILL CONTINUE TO MONITOR TRENDS AND MAY EVENTUALLY REMOVE ALL POPS FOR TODAY. WITH THIS...MODELS ARE TRENDING WARMER TODAY (THINNER CLOUD COVER)...AND FOLLOWED THIS TREND IN THE FORECAST. TONIGHT...THE NORTHERN UPPER WAVE IS QUITE STRONG...AND MODELS HAVE BEEN CONSISTENT SPREADING SNOW INTO PARTS OF THE NORTHERN FA (WITH AN INCH OR TWO POSSIBLE). MONDAY...REGION WILL BE BETWEEN SYSTEMS ALONG WITH WARM AIR ADVECTION AHEAD OF THE NEXT SYSTEM. SHOULD BE A RELATIVELY QUIET DAY WITH MAX TEMPS APPROACHING OR INTO THE 40S. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAR 22 2015 MONDAY NIGHT-TUESDAY NIGHT...STRONGER SYSTEM WILL AFFECT THE REGION...MOST LIKELY LATER TUESDAY INTO TUESDAY NIGHT. CONFIDENCE IS HIGH THAT SOMETHING IS GOING TO OCCUR...ALTHOUGH MODELS ARE ALL OVER THE PLACE WITH DETAILS SO EXACTLY WHAT OCCURS IS HIGHLY QUESTIONABLE. GENERALLY...THE REGION WILL BE WITHIN AN INVERTED TROUGH WITH RAIN EVENTUALLY CHANGING TO SNOW. SOME MODELS ARE INDICATING OVER A FOOT OF SNOW...WITH OTHERS FAR LESS (OR ALMOST NOTHING). MUCH WILL DEPEND ON HOW THE SYSTEM EVOLVES...AND WHEN/WHERE THE SOUTHERN SFC LOW STRENGTHENS (WHICH WILL INFLUENCE THE STRENGTH OF THE INVERTED TROUGH AND THUS QPF AMOUNTS). FOR NOW...THE BEST THING TO SAY IS RAIN CHANGING TO SNOW WITH SOME ACCUMULATIONS POSSIBLE. WEDNESDAY-SATURDAY...THE BACKSIDE OF THE FULLY DEVELOPED CLOSED- LOW SYSTEM OVER WISCONSIN AND MOVING EASTWARD WILL BRING AN END TO THE PRECIPITATION OVER WEST-CENTRAL MINNESOTA WITH THE NORTHERLY WINDS ADVECTING IN SOME COOLER DAYTIME TEMPERATURES IN THE 30S AND LOWS IN THE TEENS FOR WEDNESDAY. A SURFACE HIGH PRESSURE SYSTEM WILL BE IN PLACE OVER THE AREA BY THURSDAY AHEAD OF A BUILDING UPPER-AIR RIDGE ON THE WEST COAST. THAT HIGH WILL BE SHIFTING TO THE EAST WITH SOME SOUTHERLY WINDS ON ITS BACKSIDE BRINGING IN SOME WARMER AIR FOR FRIDAY AND SATURDAY. HOWEVER...AN EMBEDDED UPPER-AIR SHORT WAVE EMBEDDED IN THE NORTHWEST FLOW FROM WESTERN RIDGE WILL BRING GOOD CHANCES FOR WEEKEND PRECIPITATION AS ANOTHER SURFACE LOW SPINS UP TO TRAVERSE THE REGION OVER THE WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 650 AM CDT SUN MAR 22 2015 DRY LOW LEVEL AIRMASS WILL REMAIN IN PLACE TODAY...LEADING TO VFR CIGS. ANTICIPATE THESE CONDITIONS WILL CONTINUE INTO THE OVERNIGHT HOURS...WITH ANY -SN CHANCES REMAINING AWAY FROM THE TAF SITES (TO THE SOUTH TODAY...AND TO THE NORTH TONIGHT). && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...TG SHORT TERM...TG LONG TERM...TG/LUKES AVIATION...TG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
511 AM CDT SUN MAR 22 2015 .UPDATE... ISSUED AT 512 AM CDT SUN MAR 22 2015 QUICK UPDATE TO ISSUE A FREEZING RAIN ADVISORY FOR THE SOUTHWEST CORNER. JUST HAD A REPORT OF ICY CONDITIONS NEAR HEBRON ON I94 WITH AN ACCIDENT AND SEMI TRUCKS STRUGGLING TO DRIVE UP HILLS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM CDT SUN MAR 22 2015 FORECAST HIGHLIGHTS AND CHALLENGES IN THE SHORT TERM PERIOD WILL BE THE THREAT FOR FREEZING PRECIPITATION ACROSS THE SOUTHWEST THIS MORNING...AND HOW PRECIPITATION EVOLVES EASTWARD. CURRENTLY...ACTIVE ZONAL FLOW ALOFT WITH A POTENT SHORT WAVE MOVING EAST INTO SOUTH CENTRAL CANADA AND ANOTHER MORE SUBTLE/EMBEDDED FEATURE MOVING EAST ACROSS NORTHERN WYOMING/SOUTHEASTERN MONTANA. ASSOCIATED SURFACE LOWS OVER SOUTHERN SASKATCHEWAN AND EASTERN WY/SOUTHWESTERN SD RESPECTIVELY. THE SOUTHERN MOST WAVE IS OUR MAIN CONCERN...GENERATING PRECIPITATION FROM SOUTHEASTERN MONTANA EAST TO ACROSS SOUTHWESTERN NORTH DAKOTA. THERMAL PROFILES AND SFC TEMPERATURES INDICATING LIGHT FREEZING RAIN IS LIKELY FALLING. MADE A FEW CALLS TO THE SOUTHWEST WHICH INDICATED NO IMPACTS AS SO FAR THE LIGHT FREEZING PRECIP IS ONLY TRACING OUT. A VERY DRY EASTERLY FLOW IS KEEPING THE BOUNDARY LAYER RATHER DRY FROM THE SURFACE UP TO 5-7K FT AGL...SO ANY MOISTURE REACHING THE GROUND SHOULD BE LIMITED. WILL MAINTAIN LIKELY POPS SOUTHWEST INTO SOUTH CENTRAL. HAVE A SPECIAL WEATHER STATEMENT OUT NOW FOR THE FREEZING RAIN POTENTIAL...AND WILL CONTINUE WITH THIS UNLESS WE HEAR OF MORE IMPACTS AND A FREEZING RAIN ADVISORY BECOMES NEEDED. MORE RADAR RETURNS ACROSS THE NORTH...BUT AGAIN WITH CLOUD BASES AT ROUGHLY 8-10K AGL...ANTICIPATE LITTLE IS REACHING THE GROUND SO WILL KEEP POPS BELOW LIKELY THERE. MODELS HAVING A HARD TIME THIS MORNING WITH EACH RUN OF THE HRRR AND NAM MODELS DIFFERENT. BASICALLY WENT WITH A BLEND WHICH FOLLOWS THE 00Z ECMWF AND LATEST 06Z NAM RATHER WELL. THIS CONFINES HIGHER POPS THIS MORNING TO MY SOUTHERN COUNTIES...ALONG TO SOUTH OF INTERSTATE 94. MAIN THREAT FOR FREEZING RAIN WILL REMAIN WEST OF THE MISSOURI RIVER ACROSS MY SOUTHWEST THROUGH MID MORNING...WITH THERMAL PROFILES SUGGESTING ALL SNOW TO THE EAST. SURFACE FRONTAL BOUNDARY MOMENTARILY STALLS ACROSS THE WEST THIS AFTERNOON...WITH A WESTERLY WIND TO THE WEST AND SOUTHERLY WIND TO THE EAST. NAM AND RAP ARE INDICATING POSSIBLE STRATUS DEVELOPMENT ALONG TO EAST OF THE BOUNDARY LATER TODAY INTO THIS EVENING AS THE SOUTH/SOUTHEASTERLY FLOW TRANSPORTS MOISTURE NORTH. THUS WILL KEEP SKY COVER ELEVATED ABOVE MOSTLY SUNNY/MOSTLY CLEAR. CONFIDENCE NOT HIGH WITH THIS PLAYING OUT WITH MODELS STRUGGLING THE PAST FEW RUNS. AFOREMENTIONED STRONG SHORT WAVE CUTTING EAST ACROSS SOUTH CENTRAL CANADA WILL TURN SOUTHEAST AND MOVE INTO FAR NORTHEASTERN ND/NORTHERN MINNESOTA THIS SUNDAY NIGHT. PRECIPITATION IN THE FORM OF SNOW MAY GRAZE MY FAR NORTHEAST SO WILL MAINTAIN A LOW POP THERE TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 414 AM CDT SUN MAR 22 2015 THE PRIMARY CONCERN IN THE LONG TERM PERIOD WILL BE THE POTENT STORM MONDAY NIGHT INTO TUESDAY. THE LATEST MODEL SUITE CONTINUES TO ADVERTISE A POTENT STORM SYSTEM ACROSS THE NORTHERN PLAINS MONDAY NIGHT INTO TUESDAY. DETAILS REGARDING THE EXACT TRACK OF THE SYSTEM REMAIN ELUSIVE WITH THE 00Z GFS AND ECMWF STILL SHOWING DIFFERENCES...AND LARGE SPREAD INDICATED BY THE GEFS. THE ECMWF AND GFS BOTH SUGGEST TWO SURFACE LOWS WILL DEVELOP...HOWEVER THEY DIFFER ON THE PROGRESSION OF THE NORTHERN MOST LOW. THE ECMWF KEEPS THE LOWS SEPARATE WITH ONE TRACKING INTO CANADA...WHILE THE GFS MERGES THE LOWS IN MINNESOTA / WISCONSIN. HAVE AGAIN GONE WITH A BLENDED MODEL SOLUTION DUE TO THE UNCERTAINTY. THIS MAINTAINS SOME CONSISTENCY IN THE FORECAST WITH WARM AIR AND RAIN EXPECTED ACROSS MUCH OF CENTRAL AND WESTERN NORTH DAKOTA DURING THE MORNING AND AFTERNOON TUESDAY. THE EXCEPTION COULD BE THE FAR NORTH AND WEST WHERE COLDER AIR MAY FAVOR SNOW. COLD AIR ARRIVES BEHIND THE LOW TUESDAY NIGHT...WHICH SUPPORTS A THERMAL PROFILE TRANSITIONING TO SNOW ACROSS THE FORECAST AREA. CONFIDENCE IN PRECIPITATION AND / OR SNOW AMOUNTS REMAINS LOW DUE TO THE LARGE DIFFERENCES IN MODEL SOLUTIONS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 414 AM CDT SUN MAR 22 2015 FREEZING RAIN WILL BE POSSIBLE THROUGH 12-14Z FOR KISN-KDIK...ALL SNOW EAST FOR KMOT-KBIS-KJMS. CURRENT VFR CONDITIONS NOW EXPECTED TO MAINLY PERSIST. IFR CONDITIONS POSSIBLE FOR KBIS-KJMS AS SNOW DEVELOPS LATER THIS MORNING. MODELS DO INDICATE A CORRIDOR OF LOW STRATUS DEVELOPING DURING THE DAY SUNDAY INTO SUNDAY NIGHT CENTRAL IMPACTING KBIS-KMOT-KJMS. && .BIS WATCHES/WARNINGS/ADVISORIES... FREEZING RAIN ADVISORY UNTIL 11 AM CDT /10 AM MDT/ THIS MORNING FOR NDZ033-034-040>045. && $$ UPDATE...NH SHORT TERM...NH LONG TERM...CK AVIATION...NH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
638 AM EDT SUN MAR 22 2015 .SYNOPSIS... HIGH PRESSURE IN CHARGE THROUGH MONDAY. LOW PRESSURE SYSTEM BRINGS UNSETTLED WEATHER MID-WEEK. HIGH PRESSURE IN CHARGE AGAIN NEXT WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... 630 AM UPDATE...LOW TO MID TEEN DEW POINTS IN NORTHERN/EASTERN OHIO ADVECTING OUR WAY...SO TOOK A COUPLE DEGREES OFF PREVIOUS DEW POINT FORECAST...UNDERCUTTING MOS GUIDANCE. HRRR IS EVEN LOWER...BUT SEEMS TOO LOW. OTHERWISE NO CHANGES MADE. PREVIOUS DISCUSSION... COLD FRONT EXITING TO THE SOUTH EARLY THIS MORNING...WITH HIGH PRESSURE DROPPING INTO THE GREAT LAKES. THIS HIGH WILL KEEP POPS ASSOCIATED WITH A SOUTHERN STREAM SYSTEM TO OUR SOUTH AND EAST THROUGH THE NEAR TERM PERIOD. WILL HAVE SOME CIRRUS CLOUDS ASSOCIATED WITH THAT SYSTEM...AND ALSO LOOKING AT SOME CLOUDS IN THE NORTHERN PLAINS THAT WILL HEAD OUR WAY IN NW FLOW ALOFT. NORTH OF THE COLD FRONT...TEMPS WILL BE COOLER THAN YESTERDAY. TODAY HIGHS SHOULD TOP OUT IN THE 40S AND 50S...WITH 20S TO LOW 30S && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... MODELS INDICATE A WARM FRONT WILL DEVELOP TO OUR SOUTHWEST BY LATE MONDAY...WITH AN INVERTED TROF POSSIBLY EXTENDING NORTHEAST INTO OUR MOUNTAIN COUNTIES. AIRMASS SHOULD BE DRY AND DO NOT EXPECT ANY PRECIPITATION WITH THE TROF. THE WARM FRONT WILL LIFT SLOWLY NORTHEAST MONDAY NIGHT INTO TUESDAY...WITH AN INVERTED TROF REMAINING ACROSS OUR MOUNTAINS COUNTIES. MODELS SUGGEST PRECIPITATION MAY DEVELOP OVER THE MOUNTAINS LATE MONDAY NIGHT. NOT REAL CONFIDENT ABOUT THIS...SO HAVE GONE WITH SLIGHT CHANCE POPS. WARM FRONT WILL CONTINUE TO MOVE NORTHEAST BEFORE PUSHING INTO THE REGION TUESDAY NIGHT...AND THEN NORTH OF THE AREA BY EARLY WEDNESDAY. THIS SHOULD RESULT IN A CHANCE OF PRECIPITATION ACROSS THE NORTHERN TWO-THIRDS OF THE AREA TUESDAY NIGHT. THE BEST CHANCES FOR PRECIPITATION SHOULD LIFT NORTH ON WEDNESDAY WITH THE WARM FRONT. A COLD FRONT WILL THEN APPROACH THE AREA BY LATE WEDNESDAY...BRINGING ADDITIONAL SHOWERS TO THE AREA. GFS SUGGESTS SOME INSTABILITY WILL DEVELOP ACROSS OUR SOUTHWESTERN COUNTIES WEDNESDAY AFTERNOON. HAVE NOT INCLUDED MENTION OF THUNDER IN FORECAST AT THIS TIME...BUT IT WILL SOMETHING THAT MAY NEED TO BE ADDED. FORECAST TEMPS LOOK GOOD AND ARE GENERALLY A MIX OF THE LATEST MET/MAV NUMBERS...SO ONLY MADE SOME TWEAKS. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... THIS PERIOD FEATURES A STRONG COLD FRONT COMING THRU LATE WEDNESDAY NIGHT AND THURSDAY. IN THIS CASE...THERE IS PHASING BETWEEN THE NORTHERN AND SOUTHERN STREAM FLOW ACROSS THE NATION...ALLOWING A DEEPENING LOW PRESSURE SYSTEM TO LIFT FROM THE PLAINS INTO THE GREAT LAKES WEDNESDAY. A WARM FRONT AHEAD OF THE LOW WILL LIFT UP TUESDAY NIGHT WITH A FEW SHOWERS MAINLY NORTH AND WEST IN THE BETTER LIFT AND MAXIMUM MOISTURE INFLOW. OTHERWISE...TUESDAY NIGHT LOOKS TO BE MILD WITH A SOUTHERLY BREEZE KICKING IN. WE WILL BE IN THE WARM SECTOR WEDNESDAY...WITH AN INCREASINGLY WARM AND MOIST SOUTHERLY FLOW UNDER PARTIAL SUNSHINE TO BRING TEMPERATURES UP AROUND 70 DEGREES. SOME SHOWERS MAY SPREAD MAINLY INTO SOUTHEAST OHIO WEDNESDAY AFTERNOON AS THE COLD FRONT APPROACHES FROM THE WEST...BUT MOST AREAS WILL BE DRY. THE COLD FRONT IS PROGGED TO MOVE ACROSS THE AREA LATE WEDNESDAY NIGHT AND THURSDAY...BUT MAY BE SLOWED A BIT AS MODELS INDICATE A POSSIBLE WAVE RIPPLING UP ALONG THE FRONT. IN ANY CASE...A GOOD SURGE OF MOIST AND MARGINALLY UNSTABLE AIR WILL COMBINE WITH UPPER DYNAMICS AHEAD OF THE COLD FRONT TO PRODUCE A BAND OF RAIN SHOWERS...AND POSSIBLY A THUNDERSTORM. UPON PASSAGE OF THE FRONT THURSDAY...MUCH COOLER BUT STILL MOIST AIR UNDER THE UPPER TROUGH WILL CONTINUE SCATTERED RAIN SHOWERS THURSDAY NIGHT AND FRIDAY... ESPECIALLY IN THE MOUNTAINS WITH AN UPSLOPE COMPONENT. ENOUGH COLD AIR ALOFT WILL MOVE IN TO CHANGE RAIN SHOWERS TO SNOW SHOWERS LATER THURSDAY NIGHT AND FRIDAY IN THE NORTHERN MOUNTAINS...BUT LITTLE ACCUMULATION IS EXPECTED. CANADIAN HIGH PRESSURE WILL FINALLY BRING DRY BUT COOL AIR FOR THE BEGINNING OF THE WEEKEND. && .AVIATION /10Z SUNDAY THROUGH THURSDAY/... SOME MVFR IN STRATUS ACROSS NORTHERN TAF SITES. CKB EVEN WENT IFR FOR A BRIEF PERIOD. HAVE MVFR AT PKB...CKB AND EKN TO START THE TAF PERIOD...WITH IMPROVEMENT TO VFR OVER THE NEXT SEVERAL HOURS. VFR EXPECTED ELSEWHERE THROUGH THE TAF PERIOD. GENERALLY LIGHT NORTHERLY WINDS EXPECTED TODAY AS HIGH PRESSURE MOVES INTO THE GREAT LAKES. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY... FORECAST CONFIDENCE: HIGH. ALTERNATE SCENARIOS: TIMING OF IMPROVEMENT OF MVFR CIGS MAY VARY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22 EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18 CRW CONSISTENCY H H H H M M H H H H H H HTS CONSISTENCY H H H H M H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY L L M M M M H H H H H H PKB CONSISTENCY M M M M H H H H H H H H CKB CONSISTENCY M M M M M H H H H H H H AFTER 12Z MONDAY... NO WIDESPREAD IFR CONDITIONS EXPECTED. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JSH/MZ NEAR TERM...MZ SHORT TERM...JSH LONG TERM...JMV AVIATION...MZ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1019 AM EDT SUN MAR 22 2015 .SYNOPSIS... A LARGE AREA OF HIGH PRESSURE WILL BUILD SOUTHEAST ACROSS THE GREAT LAKES. THIS WILL MAINTAIN BELOW NORMAL TEMPERATURES AND DRY CONDITIONS THROUGH TUESDAY. LOW PRESSURE MOVING TO OUR NORTH WILL BRING UNSETTLED CONDITIONS WITH THE CHANCE OF RAIN DURING THE SECOND PART OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A WEAK SECONDARY FRONT/ARCTIC BOUNDARY IS DROPPING SLOWLY SOUTH THROUGH SRN NY. THE SURFACE WIND FIELD SHOWS A TIDY AREA OF LOCALIZED CONVERGENCE THAT REFLECTS NICELY IN THE VISUAL CLOUD AND RADAR REFLECTIVITY FIELDS. OBSERVATIONS SHOW BRIEF VISIBILITY REDUCTIONS TO A MILE OR LESS INDICATING THE SNOW SHOWERS COULD ACTUALLY BE WHITENING THE GROUND IN A FEW SPOTS. THE HRRR CAPTURES THIS EXTREMELY SMALL FEATURE AND WEAKENS IT CONSIDERABLY AS IT DROPS INTO NRN PA. REGARDLESS...HAVE PUT FLURRIES IN THE FORECAST TO ACCOUNT FOR THIS HOPEFULLY DYING FEATURE AS IT MEANDERS INTO MY FCST AREA. THAT PRETTY MUCH SUMS UP THE NEAR TERM CHALLENGE. OTHER THAN THE CLOUDS DROPPING INTO NRN PA...THE REMAINDER OF THE REGION IS BRIGHT AND SUNNY BUT CHILLY. 22/00Z GEFS 8H NEGATIVE TEMP ANOMALIES OF MINUS 1-2 SIGMA INDICATE IT WILL BE A VERY CHILLY DAY FOR LATE MARCH. THE GREATEST TEMPS ANOMALIES CONTINUE TO LIE ACROSS THE NRN MTNS...WHERE MAX TEMPS OF ONLY THE MID-UPPER U20S ARE EXPECTED. SOME OF THE SOUTHERN VALLEYS NEAR THE MASON-DIXON LINE WILL LIKELY REACH THE L40S...WHICH IS STILL ABOUT 10 DEG BELOW NORMAL. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... 1030 MB HIGH PRESSURE WILL DRIFT SE AND BECOME LOCATED JUST NORTH OF LAKE ONTARIO EARLY MONDAY. DRY AND UNSEASONABLY CHILLY CONDITIONS WILL OCCUR DURING THIS 24 HOUR PERIOD...WITH GENERALLY CLEAR TO PARTLY CLOUDY SKIES AND A 5-8 KT NW SFC WIND. LOW TEMPS TONIGHT WILL VARY FROM 10-15F ACROSS THE NORTHERN MTNS...TO BETWEEN 20 AND 25F THROUGHOUT THE SRN VALLEYS OF THE STATE. HIGHS MONDAY WILL BE NEAR TO SLIGHTLY HIGHER THAN TODAY/S. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... LONGITUDINALLY PRONOUNCED SPLIT FLOW PATTERN WILL CONTINUE ACROSS THE CONTINENTAL US THROUGH THE PERIOD. ZONAL TO SWRLY FLOW IN THE NRN STREAM WILL DOMINATE MUCH OF THE LONG TERM PERIOD OVER THE NORTHEASTERN PART OF THE COUNTY...PROVIDING DRY WEATHER EARLY IN THE PD...UNTIL A STRONG NRN STREAM WAVE...POSSIBLY PHASED WITH SOUTHERN STREAM ENERGY...ARRIVES MID WEEK. ARCTIC HIGH WILL BUILD INTO THE REGION BEHIND EXITING COLD FRONT SUN NIGHT INTO TUESDAY...WITH BELOW NORMAL TEMPS TO START THE WEEK. TEMPS WILL BEGIN TO MODERATE TUE INTO WED AS FLOW TURNS FROM THE NW AROUND TO THE SW. DAYTIME TEMPS WILL STRUGGLE TO HIT 30F ACROSS THE NORTHERN MTNS SUN/MON WITH HIGHS ONLY AROUND 40F ACROSS THE SOUTH /AND LOWS WILL DIP INTO THE TEENS AND 20S FOR MUCH OF CENTRAL PA/. BY WED...HIGH TEMPS REBOUND INTO THE MID 40S TO MID 50S. SHARP RIDGE BUILDS ACROSS FAR WESTERN U.S. LATE WEEK...ALLOWING A WAVE TO CARVE OUT A TROUGH OVER EASTERN PORTIONS OF THE COUNTRY AS A LOW PRESSURE AREA BECOMES BETTER ORGANIZED IN THE MIDWEST. COULD SEE A PASSING SHOWER ON WED AS WARM FRONT SLIDES THROUGH...BUT MAJORITY OF PRECIP WILL HOLD OFF UNTIL THU/EARLY FRI AS ELONGATED FRONT/TROUGH MOVE SLOWLY THROUGH THE REGION WITH SURFACE LOW TRACKING TO OUR NORTH. RAIN CHANCES DURING THAT WINDOW OF TIME WILL BE IN THE HIGH CHANCE/LOW LIKELY CATEGORY. ECMWF SUITE FASTER THAN THE GFS WITH THE TROUGH...SO THESE DIFFERENCES WILL NEED TO BE RESOLVED IN FUTURE RUNS TO INCREASE FORECAST CONFIDENCE. BEHIND THAT SYSTEM...A SHOT OF COOLER AIR RETURNS BRINGING ANOTHER PERIOD OF BELOW NORMAL TEMPS AND SCT MAINLY LIGHT RAIN/SNOW SHOWERS FOR LATER FRI INTO THE WEEKEND. && .AVIATION /13Z SUNDAY THROUGH THURSDAY/... SOME LOCALIZED MVFR CONTINUES TO AFFECT BFD AS SOME LAKE MOISTURE AND FLURRIES DROP INTO THE AREA. OTHERWISE VFR CONDITIONS WILL PREVAIL AT MOST SITES THROUGH THE PERIOD. SFC WINDS FROM 300-330 AT 10KTS MAY GUST UP TO 20KT AT TIMES THIS AFTN BEFORE DECREASING AFT 00Z. HIGH PRESSURE WILL CONTINUE TO PROMOTE FAIR/DRY WX AND VFR FLYING EARLY THIS WEEK. OUTLOOK... MON-TUE...VFR/NO SIG WX. WED-THU...RESTRICTIONS PSBL/CHC OF RAIN WITH NEXT FRONTAL SYSTEM. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LA CORTE/LAMBERT SHORT TERM...FITZGERALD/LA CORTE/LAMBERT LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE/STEINBUGL
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
136 PM EDT SUN MAR 22 2015 .SYNOPSIS... SEVERAL WAVES OF LOW PRESSURE WILL PASS SOUTH OF THE AREA ALONG A STALLED FRONT THEN SHIFT OFFSHORE INTO THE ATLANTIC TODAY AND TONIGHT. AN INLAND WEDGE OF HIGH PRESSURE WILL THEN STRENGTHEN ON MONDAY AS ANOTHER AREA OF LOW PRESSURE SHIFTS OFF THE SOUTHEAST COAST. HIGH PRESSURE WILL LEAD TO DRY CONDITIONS TUESDAY WITH A WARMING TREND INTO FRIDAY AHEAD OF THE NEXT COLD FRONT. UNSEASONABLY COOL TEMPERATURES ARE THEN LIKELY AT THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE RAIN HAS BEEN PRETTY LIGHT SO FAR AND MAINLY CONCENTRATED ACROSS THE CENTRAL AND NORTHERN PARTS OF THE FORECAST AREA. THE RAIN WILL REMAIN FAIRLY LIGHT FOR THE REMAINDER OF THE AFTERNOON AS THE 850 HPA WARM FRONT MEANDERS OVERHEAD. THE EXPECTED TIGHTENING OF THE ELEVATED FRONT HAS BEEN DELAYED SOMEWHAT PER LATEST RAP UPPER AIR PROGS...BUT THE LOW-LEVEL JET THAT WILL ENHANCED RAINFALL FOR THE NEXT 12 HOURS SO IS JUST NOW MOVING INTO THE WESTERN FLORDIA PANHANDLE/SOUTHWEST GEORGIA WHERE RADAR COMPOSITES SHOW AN INCREASING AREA OF MODERATE TO HEAVY RAIN ALONG THE GULF COAST. HAVE REORIENTED POPS BASED ON CURRENT RADAR AND SHORT TERM MODEL TRENDS. THIS YIELDS CONSIDERABLY LOWER POPS AND QPF SOUTH OF THE I-16 CORRIDOR. HAVE ALSO NUDGED LOWS DOWN 1-2 DEGS ACROSS THE NORTH AND RAISED THEM 1-2 DEGREES ACROSS THE SOUTH WHERE RAIN WILL BE MUCH MORE SPOTTY/LIGHT. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... TONIGHT...A SHORT WAVE TROUGH WILL SHIFT ACROSS THE LOWER MISSISSIPPI VALLEY...WHILE AT THE SURFACE ADDITIONAL WAVES OF LOW PRESSURE CONTINUE TO TRACK ALONG THE STALLED FRONT TO THE SOUTH BEFORE MOVING OFF THE SOUTHEAST COAST. DEEP MOISTURE...INCREASED FORCING FOR ASCENT WITH A PASSING DISTURBANCE ALOFT...AND CONTINUED STRONG ISENTROPIC ASCENT AND THETA-E ADVECTION WILL SUPPORT PERIODS OF RAIN THROUGH THE EVENING AND INTO THE OVERNIGHT HOURS. THERE IS THEN SOME INDICATION THAT AN AREA OF WEAK SUBSIDENCE COULD DEVELOP BEHIND THE PASSING DISTURBANCE /BUT AHEAD OF THE MAIN SHORT WAVE TROUGH/ AND SOMEWHAT OF A DRY SLOT COULD OVERSPREAD THE AREA LATE. GIVEN THIS POTENTIAL...THE FORECAST DOES SHOW DECREASING RAIN CHANCES OVERNIGHT FROM THE WEST...WITH PROBABILITIES FALLING INTO THE CHANCE CATEGORY ACROSS PORTIONS OF INTERIOR SOUTHEAST GEORGIA LATE. TEMPERATURES SHOULD FALL TO LOWS IN THE LOWER TO MID 50S ACROSS MUCH OF THE AREA. MONDAY...LOW PRESSURE WILL CONTINUE TO PUSH OFFSHORE IN ACCORDANCE WITH AN UPPER LEVEL TROUGH WHICH SHOULD BE NEAR THE COAST EARLY IN THE EVENING. LOOKS LIKE A RATHER WET AND COOL DAY ACROSS THE AREA GIVEN THE ABUNDANT MOISTURE/CLOUDS IN PLACE WITHIN THE HIGH PRESSURE WEDGE PATTERN. TEMPS WILL LIKELY REMAIN IN THE 50S MOST LOCALES. IT WILL ALSO BE BREEZY GIVEN THE TIGHT PRESSURE GRADIENT WITH SOME GUSTS 25 TO POSSIBLY 30 MPH NEAR THE COAST...LIKELY STRONGEST OVER SC. RAIN CHANCES LOWER TUESDAY NIGHT BUT THERE WILL STILL BE A FEW SHOWERS AROUND GIVEN THE LINGERING LOW-LEVEL MOISTURE CONVERGENCE AND WEAK SHORTWAVE ENERGY ALOFT. TUESDAY...EXPECT SOME IMPROVEMENT AS LOW PRESSURE DEPARTS THE AREA ALTHOUGH THE LATEST MODEL GUIDANCE SUGGEST SOME SHOWERS COULD LINGER...AT LEAST NEAR THE COAST...AS A COASTAL TROUGH DEVELOPS. TEMPS SHOULD GET INTO THE 60S MOST PLACES...ESPECIALLY GA. WEDNESDAY...THE COASTAL TROUGH OFFSHORE LOOKS TO PUSH INLAND AND NORTH OF THE AREA AS A WARM FRONT AS HIGH PRESSURE TO THE NORTH MOVES FARTHER EAST. THIS WILL LEAD TO WARMER TEMPERATURES BACK INTO THE 70S AWAY FROM THE COOLER COASTAL AREAS...AS WELL AS A FEW SHOWERS. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... HIGH PRESSURE OFFSHORE WILL MAINTAIN A WARMER THAN NORMAL PATTERN INTO THURSDAY NIGHT BEFORE THE NEXT COLD FRONT PUSHES THROUGH...MOST LIKELY EARLY FRIDAY. TEMPS COULD BE NEAR 80 THURSDAY WITH A FEW SHOWERS AND THUNDERSTORMS AROUND...THEN WILL DROP BACK INTO THE 60S FRIDAY WITH SOME MORE SHOWERS THANKS TO A STRONG UPPER TROUGH/JET APPROACHING FROM THE WEST. THE COOLING TREND WILL CONTINUE OVER THE UPCOMING WEEKEND AS THE TROUGH MOVES THROUGH WITH 30S POSSIBLE EACH MORNING...ESPECIALLY SUNDAY WHEN FROST AND MAYBE EVEN FREEZE CONDITIONS ARE POSSIBLE INLAND. THOSE WILL AGRICULTURAL INTERESTS SHOULD CAREFULLY MONITOR TEMPERATURES THIS WEEKEND GIVEN THE POTENTIAL IMPACT TO CROPS. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... VFR AND MVFR CONDITIONS HAVE LARGELY PERSISTED THROUGH THE LATE MORNING AND EARLY AFTERNOON HOURS AT BOTH KSAV AND KCHS. EXPECT THIS TREND TO CONTINUE THROUGH THE REST OF THE AFTERNOON AND INTO THE EVENING DESPITE AN INCREASE IN RAINFALL COVERAGE AS THE MID-LEVELS CONTINUE TO SATURATE AND THE INVERSION AROUND 900 MB CONTINUES TO WEAKEN. CEILINGS WILL LOWER THIS EVENING AND TONIGHT AS THE DYNAMIC CORE OF THE LOW PRESSURE PASSES TO THE SOUTH ALONG THE GA/FL BORDER. EXPECT LOWER CEILINGS AT KSAV THAN KCHS DUE TO THE CLOSER PROXIMITY TO THE INSTABILITY. IFR CONDITIONS SHOULD BEGIN AT KSAV JUST BEFORE SUNSET AND AT KCHS JUST AFTER SUNSET. KSAV SHOULD FURTHER DETERIORATE TO LIFR AS THE LOW SLIDES OFF THE GA COAST OVERNIGHT. GREATEST FORECAST CHALLENGE AT THIS POINT IS JUST HOW LOW THE CEILINGS WILL GO AT KSAV DURING THE MONDAY EARLY MORNING HOURS AND HOW LOW THEY WILL STAY LIFR. A LOW LEVEL JET DEVELOPING AS THE LOW PASSES OFF OF THE CAROLINA COAST MONDAY MORNING WILL BRING INCREASINGLY BREEZY CONDITIONS TO KCHS. HAVE GUSTS BEGINNING AT 8Z. RELATIVELY DRIER AIR WILL COME IN WITH THE JET...SIGNALING A DECREASE IN RAIN INTENSITY AND IMPROVING CEILINGS BY MID-MORNING FOR KCHS...AND MIDDAY FOR KSAV. EXTENDED AVIATION OUTLOOK...HIGH CONFIDENCE IN MVFR/IFR CONDITIONS MONDAY-WEDNESDAY...ESPECIALLY AT KSAV...DUE TO LOW CLOUDS AND RAIN. EXPECT BREEZY N/NE WINDS MONDAY. && .MARINE... WEBCAMS AND SURFACE DATA SUGGEST ANY SIGNIFICANT SEA FOG HAS LIKELY DISSIPATED AND WITH NORTHEAST WINDS EXPECTED TO STRENGTHEN THROUGH THE DAY...THE RISK FOR ADDITIONAL DEVELOPMENT IS LOW. THE MARINE DENSE FOG ADVISORY WILL BE CANCELLED. TODAY AND TONIGHT...LOW PRESSURE OFF THE SOUTHEAST COAST AND HIGH PRESSURE TO THE NORTH WILL RESULT IN A STRENGTHENING NORTHEAST FLOW ACROSS THE WATERS THROUGH TONIGHT. WIND AND WAVE CONDITIONS WILL DETERIORATE...REACHING SMALL CRAFT ADVISORY CRITERIA ACROSS THE CHARLESTON COUNTY NEAR SHORE WATERS BY THIS EVENING...THEN IN THE FAR SOUTHERN SOUTH CAROLINA WATERS AND CHARLESTON HARBOR AFTER MIDNIGHT. THERE IS A SMALL POTENTIAL THAT IF THE GRADIENT PINCHES SUFFICIENTLY...THAT WIND GUSTS COULD APPROACH GALE FORCE LATE TONIGHT OVER THE CHARLESTON COUNTY NEAR SHORE WATERS. DESPITE LIMITED OBSERVED DATA...HIGH RESOLUTION MODELS CONTINUE TO INDICATE SEA FOG PLAGUING PORTIONS OF THE NEAR SHORE WATERS SOUTH OF EDISTO BEACH. IT VERY WELL COULD BE JUST LOW STRATUS...BUT PREFER TO BE CAUTIOUS AND HAVE THEREFORE EXTENDED THE MARINE DENSE FOG ADVISORY THROUGH NOON. IF THE FOG HAS NOT ERODED BY THAT TIME...IT VERY WELL SHOULD THIS AFTERNOON GIVEN STRENGTHENING WINDS. MONDAY THROUGH FRIDAY...SOME DENSE FOG COULD OCCUR OVER THE COOL NEARSHORE WATERS INTO EARLY MONDAY...MAINLY A RESULT OF LOWERING STRATUS. OTHERWISE...EXPECT DETERIORATING CONDITIONS MONDAY WHEN THE PRESSURE GRADIENT TIGHTENS BETWEEN HIGH PRESSURE INLAND AND LOW PRESSURE PASSING BY TO THE SOUTH. THIS WILL LIKELY RESULT IN NORTHEAST WINDS REACHING CLOSE TO GALE FORCE AND SEAS BUILDING TO AROUND 8 FT WHICH WOULD NECESSITATE SMALL CRAFT ADVISORIES AND POSSIBLY EVEN GALE WARNINGS /ESPECIALLY OFF CHARLESTON COUNTY AND THE GA WATERS BEYOND 20 NM/. FOR NOW WE HAVE ISSUED A GALE WATCH FOR THE WATERS OFF CHARLESTON COUNTY WHERE CONFIDENCE IS GREATEST. CONDITIONS WILL THEN IMPROVE LATER TUESDAY WITH ADVISORY-LEVEL SEAS HANGING ON LONGER BEYOND 20 NM...LIKELY INTO THURSDAY. ANOTHER SURGE EXPECTED LATER FRIDAY BEHIND A COLD FRONT BUT ADVISORIES ARE UNLIKELY AT THIS POINT. && .TIDES/COASTAL FLOODING... ANOTHER ELEVATED HIGH TIDE WILL OCCUR LATE THIS EVENING WITH SHALLOW COASTAL FLOODING LIKELY ALONG MUCH OF THE LOWER SOUTH CAROLINA AND UPPER GEORGIA COASTS. ELEVATED TIDES COUPLED WITH STRENGTHENING NORTHEAST WINDS WILL LIKELY PUSH TIDE LEVELS HIGHER THAN WHAT WAS OBSERVED WITH HIGH TIDE YESTERDAY EVENING. A COASTAL FLOOD ADVISORY WILL BE ISSUED FOR ALL COASTAL ZONES... INCLUDING TIDAL BERKELEY...FROM 9PM-1AM TONIGHT. EXPECT TIDE LEVELS TO POSSIBLY APPROACH MODERATE FLOOD THRESHOLDS AT THE CHARLESTON HARBOR /7.5 FT MLLW/ GAGE...BUT REMAIN WELL WITHIN SHALLOW COASTAL FLOODING THRESHOLDS AT FORT PULASKI. WILL FORECAST 7.3-7.5 FT MLLW FOR CHARLESTON HARBOR AND 9.1-9.3 FT AT FORT PULASKI. TIDES WILL REMAIN ELEVATED DUE TO THE RECENT NEW MOON AND PERIGEE....ENHANCED BY STRENGTHENING NORTHEAST WINDS THROUGH MONDAY. TIDE LEVELS COULD REACH COASTAL FLOOD ADVISORY CRITERIA DURING THE EVENING HIGH TIDE CYCLES THROUGH MONDAY. WILL CONTINUE TO MENTION THE POTENTIAL FOR SHALLOW SALTWATER INUNDATION AROUND THE COAST IN THE HAZARDOUS WEATHER OUTLOOK. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...COASTAL FLOOD ADVISORY FROM 9 PM THIS EVENING TO 1 AM EDT MONDAY FOR GAZ117-119-139-141. SC...COASTAL FLOOD ADVISORY FROM 9 PM THIS EVENING TO 1 AM EDT MONDAY FOR SCZ048>052. MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EDT TUESDAY FOR AMZ352. GALE WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING FOR AMZ350. SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 8 AM EDT MONDAY FOR AMZ350. SMALL CRAFT ADVISORY FROM 8 AM MONDAY TO NOON EDT TUESDAY FOR AMZ354. SMALL CRAFT ADVISORY FROM 8 AM MONDAY TO 4 AM EDT THURSDAY FOR AMZ374. SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO MIDNIGHT EDT MONDAY NIGHT FOR AMZ330. && $$ ST/CEB
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
250 PM CDT SUN MAR 22 2015 .UPDATE...1025 AM CDT ONLY SMALL CHANGES MADE TO THE FORECAST FOR THIS AFTERNOON. HAVE ADDED THE MENTION OF SOME FLURRIES OR POSSIBLY SPRINKLES THIS AFTERNOON IN FAR NORTHERN ILLINOIS...BUT AS FOR THIS EVENING CONTINUE TO DELAY MENTION OF MEASURABLE PRECIPITATION CHANCES. A CANOPY OF MID-LEVEL CLOUDS FROM SOUTHERN/CENTRAL MN THROUGH FAR NORTHERN IL AND SOUTHERN LAKE MI HIGHLIGHTS A WEAK ZONE OF MID-LEVEL FORCING ALONG A MODEST THERMAL GRADIENT. THE NATURE OF SOME OF THE SOUTHERN EDGE CLOUDS AS WELL AS 35-40DBZ ECHOES ON COMPOSITE RADAR NEAR THE IA/MN BORDER INDICATE THE PRESENCE OF AT LEAST WEAK INSTABILITY ALOFT AND LIKELY THE RESULT OF A SUBTLE MID-LEVEL PERTURBATION PER SATELLITE AND RAP ANALYSIS. IT IS POSSIBLE AS THIS CORRIDOR OF SHOWERY-TYPE ECHOES BRINGS SOME SPRINKLES OR FLURRIES TO FAR NORTHERN IL EARLY TO MID AFTERNOON...SO THAT IS WHY THE EARLIER MENTION IN THE FORECAST. OVERALL THOUGH...THE DRIER SYNOPTIC AIR AND DRY 925-850MB TRAJECTORIES WILL LIKELY PREVENT ANY NOTEWORTHY PRECIP INTO THIS EVE AND POSSIBLY THROUGH EARLY OVERNIGHT UNTIL STRONGER FORCING WITH THE MAIN UPPER SHORT WAVE APPROACH. THE CHALLENGE WITH THIS UPCOMING SNOW EVENT LOOKS TO BE IF THERE WILL BE A CORRIDOR/BAND OF MODERATE SNOWFALL RATES DURING THE DAYBREAK THROUGH MID-MORNING HOURS ON MONDAY...WHICH SOME HIGH RESOLUTION MODELS INCLUDING THE 12Z NAM INDICATE AND THIS MAKES SENSE SOMEWHERE IN THE REGION WITH THIS TYPE OF SYSTEM. IT IS JUST PLACEMENT AND DURATION IS THE CHALLENGE. THESE MORE APPRECIABLE RATES EVEN IF TEMPORARY WOULD HAVE AT LEAST A SLIGHTLY GREATER IMPACT DUE TO OVERCOMING THE NOW WARMER PAVEMENT AND GROUND TEMPERATURES. WILL CONTINUE TO LOOK AT GUIDANCE AND REFINE THE FORECAST WITH MORE TEMPORAL AND SPATIAL RESOLUTION FOR MONDAY MORNING AND IF NEEDED ISSUE SOME FORM OF STATEMENT TO FURTHER HIGHLIGHT. MTF && .SHORT TERM... 235 AM CDT THROUGH MONDAY... MAIN CONCERN IN THE SHORT TERM WILL REVOLVE AROUND TIMING OF A DEVELOPING MID-LVL SHORTWAVE FOR LATE TONIGHT INTO MONDAY MORNING...WHICH WILL LIKELY BRING SOME LIGHT ACCUMULATING SNOWFALL TO MAINLY NORTHERN IL. PRIOR TO THE ARRIVAL OF THIS SYSTEM...EARLY THIS MORNING THE SURFACE ANTI-CYCLONIC FEATURE REMAINED CENTERED OVER THE GREAT LAKES REGION. THIS FEATURE WAS SENDING MUCH DRIER AIR SOUTH ACROSS THE WESTERN GREAT LAKES WITH NUMEROUS LOCATIONS IN WISC SEEING DEW PTS IN THE SINGLE DIGITS TO LOW TEENS...ALTHOUGH ACROSS NORTHERN IL DEW PTS REMAINED IN THE LOW/MID 20S. THIS WAS A RESULT OF THE NORTHEAST WINDS ALLOWING THE MARINE ENVIRONMENT TO BLEED INLAND. GUIDANCE CONTINUES TO SUGGEST THE SFC RIDGE WILL REMAIN ORIENTED ACROSS THE UPPER MIDWEST/GREAT LAKES STRETCHING NORTH INTO CENTRAL ONTARIO THROUGH TONIGHT AND INTO MONDAY. THIS WILL MAINTAIN A COOL/DRY NORTHEAST TO EAST LLVL FLOW ACROSS THE FORECAST AREA. IR IMAGERY INDICATES A THIN CIRRUS SHIELD OVERHEAD...BUT WILL STEADILY THICKEN AS THE AFTN/EVE PROGRESSES. HIGHS TODAY WILL STRUGGLE TO WARM BEYOND THE LOW/MID 40S...WITH A FEW AREAS IN THE FAR SOUTHWEST NEARING 50. AREAS ADJACENT TO LAKE MICHIGAN WILL BE UNDER THE INFLUENCE OF A COLD MARINE ENVIRONMENT...LIKELY HOLDING TEMPS IN THE UPR 30S WITHIN THE FIRST FEW MILES OF LAND AWAY FROM THE LAKE. THE FOR TONIGHT...GUIDANCE HAS LOCKED IN THE DRY AIR WHICH APPEARS TO BE DELAYING THE MOISTENING LOW/MID LVLS UNTIL LATE TONIGHT. USING A T-LAG DISPLAY OF SOUNDINGS WOULD SUGGEST THE TREND HAS BEEN TO PUSH BACK PRECIP UNTIL ARND 6Z BUT THAT TOO COULD BE A FEW HOURS EARLY. HAVE HELD ONTO DRY CONDS LONGER WITH SLT CHC POPS ARRIVING ARND 6Z...THEN STEADILY INCREASING TO LIKELY ARND 9Z THRU ABOUT 12- 14Z. A BAROCLINIC ZONE WILL BE ORIENTED FROM SOUTHEAST IOWA EAST THROUGH CENTRAL IL INTO CENTRAL IN BY EARLY MON AFTN. THE LOW WILL LIKELY FOLLO THIS ORIENTATION AS IT NEARS THE REGION LATE TONIGHT. THERE CONTINUES TO BE SOME DEGREE OF UNCERTAINTY ON THE DURATION OF THE SNOW...HOWEVER DYNAMICALLY SPEAKING THE FORCING CRANKS UP LATE TONIGHT WITH STEEPING MID-LVL LAPSE RATES AND A TIGHTENING GRADIENT ALONG THE BAROCLINIC ZONE. WITH STRONG ASCENT ALONG THE LEADING EDGE...QUICK MOISTENING OF THE LLVLS SHUD OCCUR AND MAY ALLOW FOR A FEW HRS OF MODERATE SNOW BETWEEN 10-14Z...BEFORE THE PROFILE BEGINS TO WARM AND LIFT BEGINS TO DECREASE BY 15-17Z MON. SNOW ACCUMS ARE POSSIBLE AND TIMING APPEARS TO BE JUST PRIOR TO RUSH-HOUR MON MORNING...AND ENDING SHORTLY AFTER. CURRENT INDICATIONS ARE FOR ARND 1 INCH CLOSER TO CHICAGO...AND POSSIBLY UP TO 2 INCHES IN A FEW AREAS ALONG AND WEST OF A DIXON TO CRYSTAL LAKE LINE. THICK SOLAR SHIELDING WILL KEEP TEMPS WELL BELOW SEASONAL CONDS MON...WITH HIGHS MAINLY IN THE MID/UPR 30S. PRECIP SHUD BE ENDING BY EARLY AFTN MON. BEACHLER && .LONG TERM... 354 AM CDT MONDAY NIGHT THROUGH SATURDAY... ATTENTION DURING THE LONG TERM PERIOD IS MAINLY FOCUSED ON THE POTENTIAL FOR A GOOD STORM SYSTEM TO IMPACT THE REGION LATE TUESDAY THROUGH WEDNESDAY. MODEL GUIDANCE CONTINUES IN DECENT AGREEMENT WITH THE EVOLUTION OF A STORM SYSTEM ACROSS THE CENTRAL PORTION OF THE COUNTRY BY MID WEEK. UPPER LEVEL ENERGY EMANATING FROM THE NORTHEASTERN PACIFIC IS EXPECTED TO SHIFT EASTWARD ONSHORE ACROSS THE PACIFIC NORTHWEST BY MONDAY...THEN OVER THE ROCKIES BY TUESDAY MORNING. THIS SHOULD SPAWN SURFACE LOW PRESSURE OVER THE PLAINS DURING THE DAY TUESDAY. MODEL GUIDANCE IS ALSO INSISTENT THAT THE MAIN MID/UPPER LEVEL SHORT WAVE WILL BECOME NEGATIVELY TILTED AS IT MOVES OVER THE MID MISSOURI VALLEY LATE TUESDAY INTO TUESDAY NIGHT. AS SUCH...THIS IS SHAPING UP TO POSSIBLY BE A GOOD DYNAMIC SYSTEM CAPABLE OF PRODUCING THUNDERSTORMS OVER THE AREA...ESPECIALLY TUESDAY NIGHT...FOLLOWED BY SOME STRONG SYNOPIC WINDS INTO WEDNESDAY. IT CURRENTLY APPEARS THAT MOST OF NORTHERN ILLINOIS/NORTHWESTERN INDIANA MAY END UP STAYING DRY FOR MOST OF THE DAY TUESDAY AS MOST OF THE SHOWERS LOOK TO REMAIN FOCUSED DOWN STATE IN CLOSER PROXIMITY TO THE WARM FRONTAL BOUNDARY. FOR THIS REASON I HAVE CUT BACK ON POPS ACROSS NORTHERN ILLINOIS DURING THE DAY TUESDAY. THE BEST POTENTIAL FOR SHOWERS AND THUNDERSTORMS FOR THE AREA LOOKS TO BE TUESDAY EVENING AND INTO THE PREDAWN HOURS OF OF WEDNESDAY MORNING. THIS IS THE PERIOD WHEN THE MAIN MID LEVEL NEGATIVELY TILTED SYSTEM BEGINS TO SHIFT OVER NORTHERN ILLINOIS. AS THIS OCCURS...THE SURFACE LOW WILL ACCELERATE NORTHEASTWARD AND DEEPEN INTO WEDNESDAY. THIS WILL RAPIDLY SHIFT THE WARM FRONT AND BETTER MOISTURE FROM DOWNSTATE ILLINOIS RIGHT ACROSS THE AREA BY TUESDAY EVENING. THINGS LOOK TO DRY OUT IN A HURRY BY EARLY WEDNESDAY FOLLOWING THE PASSAGE OF THE MID LEVEL SYSTEM AND DRY PUNCH. THE MAIN WEATHER ISSUE ON WEDNESDAY WILL BE THE POTENTIAL FOR STRONG WEST- SOUTHWESTERLY WINDS. IT CURRENTLY APPEARS THAT WINDS COULD GUST TO AROUND 40 TO 45 MPH ON WEDNESDAY AS THE COMBINATION OF MUCH DRIER AIR...GOOD LARGE SCALE DECENT IN THE WAKE OF THE UPPER LEVEL SYSTEM AND SOME DECENT SURFACE PRESSURE RISES...COULD LEAD TO EFFICIENT ATMOSPHERIC MIXING OF STRONG WINDS OFF THE SURFACE. MID/UPPER LEVEL HEIGHTS ARE EXPECTED TO BUILD ACROSS WESTERN NORTH AMERICA BY MID WEEK...AND THIS WILL ULTIMATELY SET UP TROUGHING OVER THE EASTERN CONUS...FEATURING NORTHWEST FLOW ALOFT OVER THE WESTERN GREAT LAKES REGION. THEREFORE...MILD CONDITIONS TUESDAY NIGHT AND WEDNESDAY WILL TRANSITION TO COLDER WEATHER AGAIN BY THURSDAY AS THIS PATTERN ALLOWS MUCH COLDER AIR TO SPILL IN ACROSS THE EASTERN CONUS FOR THE LATER HALF OF THE WEEK. HIGHS WILL LIKELY END UP 10 TO 15 DEGREES BELOW AVERAGE FOR A FEW DAYS AT THE END OF THE PERIOD (30S TO LOW 40S). IT ALSO APPEARS THAT THERE COULD BE SOME PERIODIC EPISODES OF SNOW AND RAIN SHOWERS AS ADDITIONAL MID LEVEL DISTURBANCES SHIFT SOUTHEASTWARD ACROSS THE REGION. KJB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * EAST/NORTHEAST WINDS 10-15KT WITH HIGHER GUSTS POSSIBLE THIS AFTERNOON AND TONIGHT. * CHANCE OF FLURRIES/SPRINKLES THIS AFTERNOON/EVENING. * SNOW DEVELOPING 09Z-11Z WITH IFR CONDITIONS EXPECTED 12Z-17Z. * SNOW MIXING WITH/CHANGING TO LIGHT FREEZING DRIZZLE/LIGHT RAIN LATE MONDAY MORNING...THEN ENDING EARLY MONDAY AFTERNOON. CMS //DISCUSSION...UPDATED 18Z... MID CLOUDS WILL CONTINUE TO SPREAD SOUTHEAST ACROSS THE AREA THIS AFTERNOON AND THIS EVENING. RADAR ECHOS SUGGEST THIS MID DECK HAS EXTENSIVE VIRGA...PRECIPIATION ALOFT...WITH VERY LITTLE REACHING THE GROUND. ORD NOW REPORTING FLURRIES AND SOME FLURRIES OR SPRINKLES ARE POSSIBLE BUT NOT EXPECTING ANY RESTRICTIONS TO VIS OR CIGS. FURTHER NORTHWEST AT RFD...LOW LEVELS WILL LIKELY SATURATE SOONER AND DID INCLUDE A MENTION OF VFR SPRINKLES/ FLURRIES THIS AFTERNOON. AS AN UPPER WAVE MOVES ACROSS THE AREA MONDAY MORNING...SNOW IS EXPECTED TO DEVELOP. AT FIRST IT MAY BE MAINLY ACROSS SOUTHERN WI AND FAR NORTHERN IL BEFORE EXPANDING/DEVELOPING ACROSS THE ENTIRE AREA AROUND/JUST PRIOR TO DAYBREAK. THUS CONFIDENCE REGARDING SPECIFIC START TIMES AND THE ASSOCIATED VIS/CIGS IS LOW. BUT EVENTUALLY...09Z-10Z AT RFD AND 12Z-13Z AT ORD/MDW...GUIDANCE SUGGESTS A 3-6 HOUR PERIOD OF PREVAILING SNOW...POSSIBLY MODERATE SNOW. SO CONFIDENCE OF THE OVERALL TREND IS MEDIUM TO HIGH. THIS SHOULD ALLOW CIGS/VIS TO DROP TO IFR AND LIFR VIS IS ALSO POSSIBLE. PRECIP END TIME APPEARS TO BE IN THE 17Z-19Z TIME FRAME AS PRECIP SHIFTS SOUTHEAST AND THE SYSTEM BEGINS TO WEAKEN. BUT PRECIP TYPE DURING THIS TIME IS UNCERTAIN. PRECIP COULD MIX WITH FREEZING DRIZZLE AND THEN POSSIBLY END AS DRIZZLE/LIGHT RAIN. EASTERLY WINDS HAVE BEEN PREVAILING 10-15KTS ALL MORNING AND LITTLE CHANGE IS EXPECTED INTO THIS EVENING WITH SOME HIGHER GUSTS POSSIBLE. WINDS WILL REMAIN EASTERLY INTO MONDAY MORNING WITH SPEEDS LIKELY AROUND OR JUST ABOVE 10KT. CMS //ORD AND MDW CONFIDENCE...UPDATED 20Z... * HIGH FOR WINDS THRU THE PERIOD. * MEDIUM FOR FLURRIES/SPRINKLES THIS AFTERNOON. * HIGH FOR SNOW MONDAY MORNING...MEDIUM FOR ASSOCIATED CIGS/VIS AND MEDIUM FOR START/END TIMES. CMS //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...MAINLY VFR CONDS. PATCHY MVFR CIGS. TUESDAY...CHANCE OF RAIN TUESDAY AFTERNOON. RAIN LIKELY/THUNDER POSSIBLE AT NIGHT. MVFR/IFR POSSIBLE. BREEZY SOUTHEAST WINDS. WEDNESDAY...SLIGHT CHANCE OF SHOWERS WITH MVFR EARLY. GUSTY WEST- SOUTHWEST WINDS. THURSDAY...SLIGHT CHANCE OF SHOWERS. MVFR POSSIBLE. FRIDAY...VFR. SATURDAY...VFR. BEACHLER && .MARINE... 248 PM CDT A HIGH PRESSURE RIDGE EXTENDS FROM NORTHERN MANITOBA AND ONTARIO TO THE LOWER GREAT LAKES LATE THIS AFTERNOON. NORTHEASTERLY WINDS WILL BE IN PLACE TONIGHT AND STEADILY TURN EASTERLY MONDAY MORNING AS THE CENTER OF THE HIGH MOVES TO NORTHERN LAKE HURON. THE HIGH WILL CONTINUE TO THE EAST ALLOWING WINDS TO TURN SOUTHEASTERLY INTO MONDAY NIGHT. ATTENTION TURNS TO LOW PRESSURE THAT WILL BE DEVELOPING IN THE LEE OF THE ROCKIES MONDAY NIGHT THEN CONSOLIDATE AND STRENGTHEN ACROSS THE SOUTHERN PLAINS TUESDAY EVENING. THE LOW WILL THEN LIFT NORTHEAST ACROSS EASTERN IOWA AND THEN NORTHERN LAKE MICHIGAN INTO WEDNESDAY AFTERNOON WHILE MAINTAINING STRENGTH. SOUTH TO SOUTHEAST WINDS WILL INCREASE TUESDAY NIGHT...WITH A MORE DUE EAST DIRECTION ACROSS THE NORTH. WINDS WILL FLIP SOUTHWEST SOUTH OF THE LOW TRACK AND REMAIN EAST TO NORTHEAST TO THE NORTH ON WEDNESDAY. WARMER AIR WILL BE BUILDING IN SO A SHARP STABLE LAYER WILL DEVELOP LIMITING WIND GUST POTENTIAL. STILL EXPECT 30 KT ON THE OPEN WATERS BUT WITH MIXING SPREADING OFFSHORE NEARSHORE AREAS COULD EASILY SEE MID TO HIGH END GALES. THINGS SETTLE DOWN WEDNESDAY NIGHT WHILE ANOTHER WEAKER LOW MOVES UP THE OHIO VALLEY BUT STRONG HIGH PRESSURE WILL BUILD IN BEHIND IT. THIS WILL BRING A SHIFT TO NORTH TO NORTHWEST WINDS ACROSS THE LAKE THURSDAY WITH COLDER AIR ALLOWING MIXING TO DEEPEN AND BRINGING THE POTENTIAL FOR A PERIOD OF LOWER END GALES. THE HIGH WILL MOVE SOUTHWARD INTO THE PLAINS KEEPING WINDS NORTHERLY BUT ALLOWING SPEEDS TO SLACKEN THROUGH THE END OF THE WEEK AND INTO THE WEEKEND. MDB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ008...3 AM MONDAY TO NOON MONDAY. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
104 PM CDT SUN MAR 22 2015 .UPDATE... 1025 AM CDT ONLY SMALL CHANGES MADE TO THE FORECAST FOR THIS AFTERNOON. HAVE ADDED THE MENTION OF SOME FLURRIES OR POSSIBLY SPRINKLES THIS AFTERNOON IN FAR NORTHERN ILLINOIS...BUT AS FOR THIS EVENING CONTINUE TO DELAY MENTION OF MEASURABLE PRECIPITATION CHANCES. A CANOPY OF MID-LEVEL CLOUDS FROM SOUTHERN/CENTRAL MN THROUGH FAR NORTHERN IL AND SOUTHERN LAKE MI HIGHLIGHTS A WEAK ZONE OF MID-LEVEL FORCING ALONG A MODEST THERMAL GRADIENT. THE NATURE OF SOME OF THE SOUTHERN EDGE CLOUDS AS WELL AS 35-40DBZ ECHOES ON COMPOSITE RADAR NEAR THE IA/MN BORDER INDICATE THE PRESENCE OF AT LEAST WEAK INSTABILITY ALOFT AND LIKELY THE RESULT OF A SUBTLE MID-LEVEL PERTURBATION PER SATELLITE AND RAP ANALYSIS. IT IS POSSIBLE AS THIS CORRIDOR OF SHOWERY-TYPE ECHOES BRINGS SOME SPRINKLES OR FLURRIES TO FAR NORTHERN IL EARLY TO MID AFTERNOON...SO THAT IS WHY THE EARLIER MENTION IN THE FORECAST. OVERALL THOUGH...THE DRIER SYNOPTIC AIR AND DRY 925-850MB TRAJECTORIES WILL LIKELY PREVENT ANY NOTEWORTHY PRECIP INTO THIS EVE AND POSSIBLY THROUGH EARLY OVERNIGHT UNTIL STRONGER FORCING WITH THE MAIN UPPER SHORT WAVE APPROACH. THE CHALLENGE WITH THIS UPCOMING SNOW EVENT LOOKS TO BE IF THERE WILL BE A CORRIDOR/BAND OF MODERATE SNOWFALL RATES DURING THE DAYBREAK THROUGH MID-MORNING HOURS ON MONDAY...WHICH SOME HIGH RESOLUTION MODELS INCLUDING THE 12Z NAM INDICATE AND THIS MAKES SENSE SOMEWHERE IN THE REGION WITH THIS TYPE OF SYSTEM. IT IS JUST PLACEMENT AND DURATION IS THE CHALLENGE. THESE MORE APPRECIABLE RATES EVEN IF TEMPORARY WOULD HAVE AT LEAST A SLIGHTLY GREATER IMPACT DUE TO OVERCOMING THE NOW WARMER PAVEMENT AND GROUND TEMPERATURES. WILL CONTINUE TO LOOK AT GUIDANCE AND REFINE THE FORECAST WITH MORE TEMPORAL AND SPATIAL RESOLUTION FOR MONDAY MORNING AND IF NEEDED ISSUE SOME FORM OF STATEMENT TO FURTHER HIGHLIGHT. MTF && .SHORT TERM... 235 AM CDT THROUGH MONDAY... MAIN CONCERN IN THE SHORT TERM WILL REVOLVE AROUND TIMING OF A DEVELOPING MID-LVL SHORTWAVE FOR LATE TONIGHT INTO MONDAY MORNING...WHICH WILL LIKELY BRING SOME LIGHT ACCUMULATING SNOWFALL TO MAINLY NORTHERN IL. PRIOR TO THE ARRIVAL OF THIS SYSTEM...EARLY THIS MORNING THE SURFACE ANTI-CYCLONIC FEATURE REMAINED CENTERED OVER THE GREAT LAKES REGION. THIS FEATURE WAS SENDING MUCH DRIER AIR SOUTH ACROSS THE WESTERN GREAT LAKES WITH NUMEROUS LOCATIONS IN WISC SEEING DEW PTS IN THE SINGLE DIGITS TO LOW TEENS...ALTHOUGH ACROSS NORTHERN IL DEW PTS REMAINED IN THE LOW/MID 20S. THIS WAS A RESULT OF THE NORTHEAST WINDS ALLOWING THE MARINE ENVIRONMENT TO BLEED INLAND. GUIDANCE CONTINUES TO SUGGEST THE SFC RIDGE WILL REMAIN ORIENTED ACROSS THE UPPER MIDWEST/GREAT LAKES STRETCHING NORTH INTO CENTRAL ONTARIO THROUGH TONIGHT AND INTO MONDAY. THIS WILL MAINTAIN A COOL/DRY NORTHEAST TO EAST LLVL FLOW ACROSS THE FORECAST AREA. IR IMAGERY INDICATES A THIN CIRRUS SHIELD OVERHEAD...BUT WILL STEADILY THICKEN AS THE AFTN/EVE PROGRESSES. HIGHS TODAY WILL STRUGGLE TO WARM BEYOND THE LOW/MID 40S...WITH A FEW AREAS IN THE FAR SOUTHWEST NEARING 50. AREAS ADJACENT TO LAKE MICHIGAN WILL BE UNDER THE INFLUENCE OF A COLD MARINE ENVIRONMENT...LIKELY HOLDING TEMPS IN THE UPR 30S WITHIN THE FIRST FEW MILES OF LAND AWAY FROM THE LAKE. THE FOR TONIGHT...GUIDANCE HAS LOCKED IN THE DRY AIR WHICH APPEARS TO BE DELAYING THE MOISTENING LOW/MID LVLS UNTIL LATE TONIGHT. USING A T-LAG DISPLAY OF SOUNDINGS WOULD SUGGEST THE TREND HAS BEEN TO PUSH BACK PRECIP UNTIL ARND 6Z BUT THAT TOO COULD BE A FEW HOURS EARLY. HAVE HELD ONTO DRY CONDS LONGER WITH SLT CHC POPS ARRIVING ARND 6Z...THEN STEADILY INCREASING TO LIKELY ARND 9Z THRU ABOUT 12- 14Z. A BAROCLINIC ZONE WILL BE ORIENTED FROM SOUTHEAST IOWA EAST THROUGH CENTRAL IL INTO CENTRAL IN BY EARLY MON AFTN. THE LOW WILL LIKELY FOLLO THIS ORIENTATION AS IT NEARS THE REGION LATE TONIGHT. THERE CONTINUES TO BE SOME DEGREE OF UNCERTAINTY ON THE DURATION OF THE SNOW...HOWEVER DYNAMICALLY SPEAKING THE FORCING CRANKS UP LATE TONIGHT WITH STEEPING MID-LVL LAPSE RATES AND A TIGHTENING GRADIENT ALONG THE BAROCLINIC ZONE. WITH STRONG ASCENT ALONG THE LEADING EDGE...QUICK MOISTENING OF THE LLVLS SHUD OCCUR AND MAY ALLOW FOR A FEW HRS OF MODERATE SNOW BETWEEN 10-14Z...BEFORE THE PROFILE BEGINS TO WARM AND LIFT BEGINS TO DECREASE BY 15-17Z MON. SNOW ACCUMS ARE POSSIBLE AND TIMING APPEARS TO BE JUST PRIOR TO RUSH-HOUR MON MORNING...AND ENDING SHORTLY AFTER. CURRENT INDICATIONS ARE FOR ARND 1 INCH CLOSER TO CHICAGO...AND POSSIBLY UP TO 2 INCHES IN A FEW AREAS ALONG AND WEST OF A DIXON TO CRYSTAL LAKE LINE. THICK SOLAR SHIELDING WILL KEEP TEMPS WELL BELOW SEASONAL CONDS MON...WITH HIGHS MAINLY IN THE MID/UPR 30S. PRECIP SHUD BE ENDING BY EARLY AFTN MON. BEACHLER && .LONG TERM... 354 AM CDT MONDAY NIGHT THROUGH SATURDAY... ATTENTION DURING THE LONG TERM PERIOD IS MAINLY FOCUSED ON THE POTENTIAL FOR A GOOD STORM SYSTEM TO IMPACT THE REGION LATE TUESDAY THROUGH WEDNESDAY. MODEL GUIDANCE CONTINUES IN DECENT AGREEMENT WITH THE EVOLUTION OF A STORM SYSTEM ACROSS THE CENTRAL PORTION OF THE COUNTRY BY MID WEEK. UPPER LEVEL ENERGY EMANATING FROM THE NORTHEASTERN PACIFIC IS EXPECTED TO SHIFT EASTWARD ONSHORE ACROSS THE PACIFIC NORTHWEST BY MONDAY...THEN OVER THE ROCKIES BY TUESDAY MORNING. THIS SHOULD SPAWN SURFACE LOW PRESSURE OVER THE PLAINS DURING THE DAY TUESDAY. MODEL GUIDANCE IS ALSO INSISTENT THAT THE MAIN MID/UPPER LEVEL SHORT WAVE WILL BECOME NEGATIVELY TILTED AS IT MOVES OVER THE MID MISSOURI VALLEY LATE TUESDAY INTO TUESDAY NIGHT. AS SUCH...THIS IS SHAPING UP TO POSSIBLY BE A GOOD DYNAMIC SYSTEM CAPABLE OF PRODUCING THUNDERSTORMS OVER THE AREA...ESPECIALLY TUESDAY NIGHT...FOLLOWED BY SOME STRONG SYNOPIC WINDS INTO WEDNESDAY. IT CURRENTLY APPEARS THAT MOST OF NORTHERN ILLINOIS/NORTHWESTERN INDIANA MAY END UP STAYING DRY FOR MOST OF THE DAY TUESDAY AS MOST OF THE SHOWERS LOOK TO REMAIN FOCUSED DOWN STATE IN CLOSER PROXIMITY TO THE WARM FRONTAL BOUNDARY. FOR THIS REASON I HAVE CUT BACK ON POPS ACROSS NORTHERN ILLINOIS DURING THE DAY TUESDAY. THE BEST POTENTIAL FOR SHOWERS AND THUNDERSTORMS FOR THE AREA LOOKS TO BE TUESDAY EVENING AND INTO THE PREDAWN HOURS OF OF WEDNESDAY MORNING. THIS IS THE PERIOD WHEN THE MAIN MID LEVEL NEGATIVELY TILTED SYSTEM BEGINS TO SHIFT OVER NORTHERN ILLINOIS. AS THIS OCCURS...THE SURFACE LOW WILL ACCELERATE NORTHEASTWARD AND DEEPEN INTO WEDNESDAY. THIS WILL RAPIDLY SHIFT THE WARM FRONT AND BETTER MOISTURE FROM DOWNSTATE ILLINOIS RIGHT ACROSS THE AREA BY TUESDAY EVENING. THINGS LOOK TO DRY OUT IN A HURRY BY EARLY WEDNESDAY FOLLOWING THE PASSAGE OF THE MID LEVEL SYSTEM AND DRY PUNCH. THE MAIN WEATHER ISSUE ON WEDNESDAY WILL BE THE POTENTIAL FOR STRONG WEST- SOUTHWESTERLY WINDS. IT CURRENTLY APPEARS THAT WINDS COULD GUST TO AROUND 40 TO 45 MPH ON WEDNESDAY AS THE COMBINATION OF MUCH DRIER AIR...GOOD LARGE SCALE DECENT IN THE WAKE OF THE UPPER LEVEL SYSTEM AND SOME DECENT SURFACE PRESSURE RISES...COULD LEAD TO EFFICIENT ATMOSPHERIC MIXING OF STRONG WINDS OFF THE SURFACE. MID/UPPER LEVEL HEIGHTS ARE EXPECTED TO BUILD ACROSS WESTERN NORTH AMERICA BY MID WEEK...AND THIS WILL ULTIMATELY SET UP TROUGHING OVER THE EASTERN CONUS...FEATURING NORTHWEST FLOW ALOFT OVER THE WESTERN GREAT LAKES REGION. THEREFORE...MILD CONDITIONS TUESDAY NIGHT AND WEDNESDAY WILL TRANSITION TO COLDER WEATHER AGAIN BY THURSDAY AS THIS PATTERN ALLOWS MUCH COLDER AIR TO SPILL IN ACROSS THE EASTERN CONUS FOR THE LATER HALF OF THE WEEK. HIGHS WILL LIKELY END UP 10 TO 15 DEGREES BELOW AVERAGE FOR A FEW DAYS AT THE END OF THE PERIOD (30S TO LOW 40S). IT ALSO APPEARS THAT THERE COULD BE SOME PERIODIC EPISODES OF SNOW AND RAIN SHOWERS AS ADDITIONAL MID LEVEL DISTURBANCES SHIFT SOUTHEASTWARD ACROSS THE REGION. KJB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * EAST/NORTHEAST WINDS 10-15KT WITH HIGHER GUSTS POSSIBLE THIS AFTERNOON AND TONIGHT. * CHANCE OF FLURRIES/SPRINKLES THIS AFTERNOON/EVENING. * SNOW DEVELOPING 09Z-11Z WITH IFR CONDITIONS EXPECTED 12Z-17Z. * SNOW MIXING WITH/CHANGING TO LIGHT FREEZING DRIZZLE/LIGHT RAIN LATE MONDAY MORNING...THEN ENDING EARLY MONDAY AFTERNOON. CMS //DISCUSSION...UPDATED 18Z... MID CLOUDS WILL CONTINUE TO SPREAD SOUTHEAST ACROSS THE AREA THIS AFTERNOON AND THIS EVENING. RADAR ECHOS SUGGEST THIS MID DECK HAS EXTENSIVE VIRGA...PRECIPIATION ALOFT...WITH VERY LITTLE REACHING THE GROUND. ORD NOW REPORTING FLURRIES AND SOME FLURRIES OR SPRINKLES ARE POSSIBLE BUT NOT EXPECTING ANY RESTRICTIONS TO VIS OR CIGS. FURTHER NORTHWEST AT RFD...LOW LEVELS WILL LIKELY SATURATE SOONER AND DID INCLUDE A MENTION OF VFR SPRINKLES/ FLURRIES THIS AFTERNOON. AS AN UPPER WAVE MOVES ACROSS THE AREA MONDAY MORNING...SNOW IS EXPECTED TO DEVELOP. AT FIRST IT MAY BE MAINLY ACROSS SOUTHERN WI AND FAR NORTHERN IL BEFORE EXPANDING/DEVELOPING ACROSS THE ENTIRE AREA AROUND/JUST PRIOR TO DAYBREAK. THUS CONFIDENCE REGARDING SPECIFIC START TIMES AND THE ASSOCIATED VIS/CIGS IS LOW. BUT EVENTUALLY...09Z-10Z AT RFD AND 12Z-13Z AT ORD/MDW...GUIDANCE SUGGESTS A 3-6 HOUR PERIOD OF PREVAILING SNOW...POSSIBLY MODERATE SNOW. SO CONFIDENCE OF THE OVERALL TREND IS MEDIUM TO HIGH. THIS SHOULD ALLOW CIGS/VIS TO DROP TO IFR AND LIFR VIS IS ALSO POSSIBLE. PRECIP END TIME APPEARS TO BE IN THE 17Z-19Z TIME FRAME AS PRECIP SHIFTS SOUTHEAST AND THE SYSTEM BEGINS TO WEAKEN. BUT PRECIP TYPE DURING THIS TIME IS UNCERTAIN. PRECIP COULD MIX WITH FREEZING DRIZZLE AND THEN POSSIBLY END AS DRIZZLE/LIGHT RAIN. EASTERLY WINDS HAVE BEEN PREVAILING 10-15KTS ALL MORNING AND LITTLE CHANGE IS EXPECTED INTO THIS EVENING WITH SOME HIGHER GUSTS POSSIBLE. WINDS WILL REMAIN EASTERLY INTO MONDAY MORNING WITH SPEEDS LIKELY AROUND OR JUST ABOVE 10KT. CMS //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH FOR WINDS THRU THE PERIOD. * MEDIUM FOR FLURRIES/SPRINKLES THIS AFTERNOON. * HIGH FOR SNOW MONDAY MORNING...MEDIUM FOR ASSOCIATED CIGS/VIS AND MEDIUM FOR START/END TIMES. CMS //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...MAINLY VFR CONDS. PATCHY MVFR CIGS. TUESDAY...CHANCE OF RAIN TUESDAY AFTERNOON. RAIN LIKELY/THUNDER POSSIBLE AT NIGHT. MVFR/IFR POSSIBLE. BREEZY SOUTHEAST WINDS. WEDNESDAY...SLIGHT CHANCE OF SHOWERS WITH MVFR EARLY. GUSTY WEST- SOUTHWEST WINDS. THURSDAY...SLIGHT CHANCE OF SHOWERS. MVFR POSSIBLE. FRIDAY...VFR. SATURDAY...VFR. BEACHLER && .MARINE... 425 AM CDT A SURFACE RIDGE OF HIGH PRESSURE WILL SHIFT OVER SOUTHERN CANADA AND THE UPPER GREAT LAKES THROUGH MONDAY. THIS WILL RESULT IN A CONTINUED PERIOD OF NORTHERLY WINDS UP TO AROUND 20 KT TODAY AND TONIGHT. THEREFORE...EXPECT WAVES OF 3 TO 5 FEET TO CONTINUE FOR THE NEAR SHORE WATERS OF NORTHEASTERN ILLINOIS AND NORTHWESTERN INDIANA. ANOTHER STORM SYSTEM IS EXPECTED TO IMPACT THE WESTERN GREAT LAKES REGION LATE TUESDAY THROUGH WEDNESDAY. THE SURFACE LOW IS FORECAST TO TRACK EAST-NORTHEASTWARD FROM THE PLAINS TO THE UPPER GREAT LAKES BY WEDNESDAY MORNING. THIS LOOKS TO RESULT IN A PERIOD OF INCREASING SOUTHEASTERLY WINDS OF 25 TO 30 KT TUESDAY NIGHT...FOLLOWED BY A PERIOD OF STRONG WEST-SOUTHWESTERLY WINDS ON WEDNESDAY. GALE FORCE WINDS ARE POSSIBLE ON WEDNESDAY...ESPECIALLY ACROSS THE ILLINOIS AND INDIANA NEAR SHORES. WINDS WILL THEN SHIFT BACK OUT OF THE NORTH BY LATE WEEK AS A REINFORCING COLD FRONT DROPS SOUTHWARD DOWN THE LAKE. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS JACKSON KY
644 PM EDT SUN MAR 22 2015 .UPDATE... ISSUED AT 645 PM EDT SUN MAR 22 2015 BUMPED UP SKY COVER TO BETTER REFLECT CURRENT CONDITIONS...AND ALIGNED TEMPS/DEW POINTS WITH MOST RECENT OBS. KEEPING ON EYE ON SOME LIGHT RADAR RETURNS...BUT CURRENT THINKING IS THAT ANY MEASURABLE PRECIP WILL STAY SOUTH OF THE AREA TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 400 PM EDT SUN MAR 22 2015 19Z SFC ANALYSIS SHOWS HIGH PRESSURE BUILDING IN FROM THE NORTH WITH LOW PRESSURE SKIRTING THE BOUNDARY JUST TO OUR SOUTH. ON RADAR...LIGHT RETURNS KEEP TRYING TO SNEAK ACROSS OUR BORDER WITH TENNESSEE...BUT SO FAR THERE HAVE NOT BEEN ANY OBS OR REPORTS OF ANYTHING REACHING THE GROUND IN KENTUCKY. THICKENING HIGH CLOUDS ARE SEEPING NORTH ASSOCIATED WITH THE SOUTHERN SYSTEMS...BUT ONLY RECENTLY HAVE THE CLOUDS GOTTEN OPAQUE ENOUGH TO BLOCK THE SUN. WITH THE FILTERED SUNSHINE...TEMPERATURES WERE ABLE TO CLIMB INTO THE LOW 60S ACROSS THE SOUTH AND THE MID 50S TO THE NORTH. DEWPOINTS BASICALLY HELD STEADY THROUGH THE DAY SO THAT THEY STILL VARY FROM THE UPPER 20S IN THE NORTH TO LOW 40S IN THE SOUTH. MEANWHILE...WINDS REMAIN MAINLY FROM THE NORTHEAST AT 5 TO 10 KTS. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM. THEY ALL DEPICT A WEAK SOUTHERN STREAM TROUGH PASSING THROUGH THE DEEP SOUTH WHILE SOME ENERGY SLIPS INTO THE OHIO VALLEY LATE MONDAY IN THE NORTHERN STREAM. HEIGHTS WILL GRADUALLY RISE THROUGH TUESDAY MORNING AS THE SOUTHERN TROUGH DEPARTS...EVEN WITH THE NORTHERN ENERGY SCRAPING BY MONDAY NIGHT. GIVEN THE GENERAL MODEL AGREEMENT HAVE FAVORED THE HIGHER RESOLUTION NAM12 AND HRRR FOR WX DETAILS THROUGH THE SHORT TERM. SENSIBLE WEATHER WILL FEATURE THE SMALL POTENTIAL FOR SPRINKLES OR LIGHT RAIN IN FAR SOUTHERN PARTS OF THE CWA TONIGHT. OTHERWISE PARTLY TO MOSTLY CLOUDY SKIES WILL DOMINATE HELPING TO KEEP THE LID ON THE WORST OF THE COOLING OVERNIGHT. FOR MONDAY...HIGH CLOUDS WILL CONTINUE TO PLAGUE THE AREA AS WE WILL BE BETWEEN THE SYSTEMS ON OUR FRINGES. LATER THAT NIGHT THERE WILL BE A SMALL CHANCE FOR RAIN IN THE NORTHERNMOST PARTS OF EASTERN KENTUCKY AS A DEVELOPING...BUT MOSTLY DRY...WARM FRONT LIFTS THROUGH THE AREA. ONCE AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO MONDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD. AS FOR POPS...ENDED UP IN LINE WITH ALL MOS GUIDANCE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 335 PM EDT SUN MAR 22 2015 AN UPPER LEVEL TROUGH DIGGING INTO THE NORTHERN PLAINS WILL DRIVE A WARM FRONT NORTHWARD ACROSS OUR AREA ON TUESDAY. WHILE MOISTURE IS MEAGER WITH THIS FRONT...MODELS CONTINUE TO INDICATE THE POTENTIAL FOR A FEW SHOWERS. THIS WARM FRONT WILL SHIFT NORTH OF OUR AREA TUESDAY NIGHT. A WEAKENING SFC COLD FRONT ASSOCIATED WITH LOW PRESSURE OVER THE GREAT LAKES WILL DROP DOWN ACROSS THE AREA ON WEDNESDAY WHILE THE SUPPORTING UPPER LEVEL TROUGH EVENTUALLY OUT RUNS ALL OF ITS SFC FEATURES. WHILE MOISTURE REMAINS MEAGER WITH THIS SYSTEM...ISOLATED TO SCATTERED SHOWERS AND PERHAPS A STRAY THUNDERSTORM CAN NOT BE RULED OUT DURING THE DAY WEDNESDAY. ANOTHER MORE SUBSTANTIAL...DEEPER TROUGH WILL REENERGIZE THE BOUNDARY LEFT IN PLACE ACROSS THE REGION WEDNESDAY NIGHT INTO THURSDAY. THERE WILL BE ENOUGH ENERGY WITH THIS SECOND UPPER TROUGH THAT WE CAN EXPECT NUMEROUS SHOWERS TO DEVELOP ACROSS OUR AREA AS ITS INDUCED SFC LOW DEVELOPS AND PUSHES UP THE MID MISSISSIPPI... LOWER OHIO VALLEY. THIS WILL ALLOW THE SFC FRONT TO REORGANIZE AND BEGIN ITS PUSH EASTWARD AGAIN. SFC BASED INSTABILITY DOES NOT LOOK AS IMPRESSIVE BUT SHOULD BE ENOUGH TO KEEP MENTION OF A FEW THUNDERSTORMS IN THE FORECAST. WHILE THE ENDS GENERALLY REMAIN THE SAME WITH RESPECT TO SENSIBLE WEATHER...BOTH THE GFS AND ECMWF ARE IN DECENT AGREEMENT WITH THIS SCENARIO...THE GFS DOES APPEAR MORE AGGRESSIVE AND WELL DEFINED WITH ALL THE SFC FEATURES THAN THE ECMWF. IN ADDITION...MODELS SEEM TO BE TRENDING A BIT SLOWER OVERALL WITH THE EVOLUTION OF THIS PHASE OF THE EXTENDED. IN ADDITION...OUR PATTERN TURNS MUCH COLDER FROM THURSDAY NIGHT INTO THE WEEKEND AS A LARGE CANADIAN SFC HIGH PRESSURE SYSTEM SETTLES OVER THE REGION. UPPER LEVEL ENERGY CONTINUES TO DIG IN FROM THE NORTHWEST...DEEPENING THE TROUGH OVER THE OHIO AND TENNESSEE VALLEYS. DEEPER MOISTURE WILL EXIT WITH THE FRONT BY THURSDAY NIGHT...BUT AN UNSTABLE BOUNDARY LAYER WILL REMAIN IN PLACE AS THE CORE OF THE TROUGH SWINGS THROUGH ON FRIDAY. WITH STEEP LAPSE RATES...A FEW RAIN SHOWERS CAN NOT BE RULED OUT. IF FREEZING LEVELS DROP LOW ENOUGH WE COULD EVEN SEE SOME WET SNOW MIX IN OVER THE HIGHER TERRAIN. STILL SOME UNCERTAINTY IN THE MODELS WITH THE AMOUNT OF MOISTURE AND COLD AIR COMING IN...BUT THERE SEEMS TO BE A GENERAL CONSENSUS OF H850 TEMPS DROPPING TO AROUND -10C OVERHEAD BY SATURDAY MORNING. THIS COULD RESULT IN A WIDESPREAD FREEZE SATURDAY MORNING IF SFC HIGH PRESSURE BECOMES MORE CENTERED OVER EASTERN KENTUCKY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 645 PM EDT SUN MAR 22 2015 VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. A SURFACE HIGH PUSHES SOUTH TONIGHT AND INTO MONDAY AS LOW PRESSURE SCOOTS PAST TO THE SOUTH. HIGH CLOUDS OF VARYING OPACITY FROM THE SOUTHERN LOW WILL COVER THE REGION DURING THIS TIME. WINDS THROUGH MUCH OF THE TAF PERIOD WILL REMAIN GENERALLY LIGHT FROM THE NORTH TO NORTHEAST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JVM SHORT TERM...GREIF LONG TERM...ABE/RAY AVIATION...JVM/GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
400 PM EDT SUN MAR 22 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 400 PM EDT SUN MAR 22 2015 19Z SFC ANALYSIS SHOWS HIGH PRESSURE BUILDING IN FROM THE NORTH WITH LOW PRESSURE SKIRTING THE BOUNDARY JUST TO OUR SOUTH. ON RADAR...LIGHT RETURNS KEEP TRYING TO SNEAK ACROSS OUR BORDER WITH TENNESSEE...BUT SO FAR THERE HAVE NOT BEEN ANY OBS OR REPORTS OF ANYTHING REACHING THE GROUND IN KENTUCKY. THICKENING HIGH CLOUDS ARE SEEPING NORTH ASSOCIATED WITH THE SOUTHERN SYSTEMS...BUT ONLY RECENTLY HAVE THE CLOUDS GOTTEN OPAQUE ENOUGH TO BLOCK THE SUN. WITH THE FILTERED SUNSHINE...TEMPERATURES WERE ABLE TO CLIMB INTO THE LOW 60S ACROSS THE SOUTH AND THE MID 50S TO THE NORTH. DEWPOINTS BASICALLY HELD STEADY THROUGH THE DAY SO THAT THEY STILL VARY FROM THE UPPER 20S IN THE NORTH TO LOW 40S IN THE SOUTH. MEANWHILE...WINDS REMAIN MAINLY FROM THE NORTHEAST AT 5 TO 10 KTS. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM. THEY ALL DEPICT A WEAK SOUTHERN STREAM TROUGH PASSING THROUGH THE DEEP SOUTH WHILE SOME ENERGY SLIPS INTO THE OHIO VALLEY LATE MONDAY IN THE NORTHERN STREAM. HEIGHTS WILL GRADUALLY RISE THROUGH TUESDAY MORNING AS THE SOUTHERN TROUGH DEPARTS...EVEN WITH THE NORTHERN ENERGY SCRAPING BY MONDAY NIGHT. GIVEN THE GENERAL MODEL AGREEMENT HAVE FAVORED THE HIGHER RESOLUTION NAM12 AND HRRR FOR WX DETAILS THROUGH THE SHORT TERM. SENSIBLE WEATHER WILL FEATURE THE SMALL POTENTIAL FOR SPRINKLES OR LIGHT RAIN IN FAR SOUTHERN PARTS OF THE CWA TONIGHT. OTHERWISE PARTLY TO MOSTLY CLOUDY SKIES WILL DOMINATE HELPING TO KEEP THE LID ON THE WORST OF THE COOLING OVERNIGHT. FOR MONDAY...HIGH CLOUDS WILL CONTINUE TO PLAGUE THE AREA AS WE WILL BE BETWEEN THE SYSTEMS ON OUR FRINGES. LATER THAT NIGHT THERE WILL BE A SMALL CHANCE FOR RAIN IN THE NORTHERNMOST PARTS OF EASTERN KENTUCKY AS A DEVELOPING...BUT MOSTLY DRY...WARM FRONT LIFTS THROUGH THE AREA. ONCE AGAIN USED THE SHORTBLEND AS A STARTING POINT FOR T/TD/WINDS INTO MONDAY MORNING AND THE SUPERBLEND THEREAFTER. DID MAKE MINOR POINT AND TERRAIN BASED ADJUSTMENTS TO TEMPS THROUGH THE PERIOD. AS FOR POPS...ENDED UP IN LINE WITH ALL MOS GUIDANCE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 335 PM EDT SUN MAR 22 2015 AN UPPER LEVEL TROUGH DIGGING INTO THE NORTHERN PLAINS WILL DRIVE A WARM FRONT NORTHWARD ACROSS OUR AREA ON TUESDAY. WHILE MOISTURE IS MEAGER WITH THIS FRONT...MODELS CONTINUE TO INDICATE THE POTENTIAL FOR A FEW SHOWERS. THIS WARM FRONT WILL SHIFT NORTH OF OUR AREA TUESDAY NIGHT. A WEAKENING SFC COLD FRONT ASSOCIATED WITH LOW PRESSURE OVER THE GREAT LAKES WILL DROP DOWN ACROSS THE AREA ON WEDNESDAY WHILE THE SUPPORTING UPPER LEVEL TROUGH EVENTUALLY OUT RUNS ALL OF ITS SFC FEATURES. WHILE MOISTURE REMAINS MEAGER WITH THIS SYSTEM...ISOLATED TO SCATTERED SHOWERS AND PERHAPS A STRAY THUNDERSTORM CAN NOT BE RULED OUT DURING THE DAY WEDNESDAY. ANOTHER MORE SUBSTANTIAL...DEEPER TROUGH WILL REENERGIZE THE BOUNDARY LEFT IN PLACE ACROSS THE REGION WEDNESDAY NIGHT INTO THURSDAY. THERE WILL BE ENOUGH ENERGY WITH THIS SECOND UPPER TROUGH THAT WE CAN EXPECT NUMEROUS SHOWERS TO DEVELOP ACROSS OUR AREA AS ITS INDUCED SFC LOW DEVELOPS AND PUSHES UP THE MID MISSISSIPPI... LOWER OHIO VALLEY. THIS WILL ALLOW THE SFC FRONT TO REORGANIZE AND BEGIN ITS PUSH EASTWARD AGAIN. SFC BASED INSTABILITY DOES NOT LOOK AS IMPRESSIVE BUT SHOULD BE ENOUGH TO KEEP MENTION OF A FEW THUNDERSTORMS IN THE FORECAST. WHILE THE ENDS GENERALLY REMAIN THE SAME WITH RESPECT TO SENSIBLE WEATHER...BOTH THE GFS AND ECMWF ARE IN DECENT AGREEMENT WITH THIS SCENARIO...THE GFS DOES APPEAR MORE AGGRESSIVE AND WELL DEFINED WITH ALL THE SFC FEATURES THAN THE ECMWF. IN ADDITION...MODELS SEEM TO BE TRENDING A BIT SLOWER OVERALL WITH THE EVOLUTION OF THIS PHASE OF THE EXTENDED. IN ADDITION...OUR PATTERN TURNS MUCH COLDER FROM THURSDAY NIGHT INTO THE WEEKEND AS A LARGE CANADIAN SFC HIGH PRESSURE SYSTEM SETTLES OVER THE REGION. UPPER LEVEL ENERGY CONTINUES TO DIG IN FROM THE NORTHWEST...DEEPENING THE TROUGH OVER THE OHIO AND TENNESSEE VALLEYS. DEEPER MOISTURE WILL EXIT WITH THE FRONT BY THURSDAY NIGHT...BUT AN UNSTABLE BOUNDARY LAYER WILL REMAIN IN PLACE AS THE CORE OF THE TROUGH SWINGS THROUGH ON FRIDAY. WITH STEEP LAPSE RATES...A FEW RAIN SHOWERS CAN NOT BE RULED OUT. IF FREEZING LEVELS DROP LOW ENOUGH WE COULD EVEN SEE SOME WET SNOW MIX IN OVER THE HIGHER TERRAIN. STILL SOME UNCERTAINTY IN THE MODELS WITH THE AMOUNT OF MOISTURE AND COLD AIR COMING IN...BUT THERE SEEMS TO BE A GENERAL CONSENSUS OF H850 TEMPS DROPPING TO AROUND -10C OVERHEAD BY SATURDAY MORNING. THIS COULD RESULT IN A WIDESPREAD FREEZE SATURDAY MORNING IF SFC HIGH PRESSURE BECOMES MORE CENTERED OVER EASTERN KENTUCKY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 230 PM EDT SUN MAR 22 2015 VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. A SURFACE HIGH PUSHES SOUTH TONIGHT AND INTO MONDAY AS LOW PRESSURE SCOOTS PAST TO THE SOUTH. HIGH CLOUDS OF VARYING OPACITY FROM THE SOUTHERN LOW WILL COVER THE REGION DURING THIS TIME. WINDS THROUGH MUCH OF THE TAF PERIOD WILL REMAIN GENERALLY LIGHT FROM THE NORTH TO NORTHEAST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GREIF LONG TERM...ABE/RAY AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1231 PM EDT SUN MAR 22 2015 .SYNOPSIS... LOW PRESSURE WILL CONTINUE TO INTENSIFY ACROSS THE MARITIMES TODAY AND TONIGHT. CANADIAN HIGH PRESSURE WILL BUILD EAST TOWARD THE REGION LATER MONDAY THROUGH TUESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1230 PM UPDATE: LOW PRESSURE NEAR THE EASTERN TIP OF NOVA SCOTIA WILL CONTINUE TO INTENSIFY AS IT ROTATES NORTHWEST ACROSS THE CANADIAN MARITIMES TODAY. A STRONG PRESSURE GRADIENT ACROSS THE AREA WILL RESULT IN GUSTY WEST WINDS TODAY ALONG WITH SOME LIGHT SNOW ACROSS NORTHERN AREAS. WINDS COULD GUST AS HIGH AS 45 TO 50 MPH AT TIMES ESPECIALLY ACROSS THE HIGHER TERRAIN. ANY ADDITIONAL SNOW ACCUMULATION WILL BE AN INCH OR LESS. THE BIGGER CONCERN WILL BE AREAS OF BLOWING SNOW MAINLY ACROSS NORTHERN AREAS THAT WILL ABRUPTLY REDUCE VISIBILITY AT TIMES ESPECIALLY ON NORTH-SOUTH ROADS. FOR THIS REASON, WE WILL KEEP THE WINTER WEATHER ADVISORY GOING TODAY. WILL ALSO KEEP THE WIND ADVISORY GOING ACROSS CENTRAL AND DOWN EAST AREAS FOR TODAY. ALL-IN-ALL, THE CURRENT FORECAST HAS THINGS COVERED QUITE NICELY AND NO SIGNIFICANT ADJUSTMENTS WERE MADE TO THE FORECAST ON THIS UPDATE. PREVIOUS DISCUSSION OTHERWISE...LATEST HRRR SIM RADAR IMAGERY SHOWS MUCH OF THE REMAINING PTN OF STEADY SN RETREATING INTO NRN NB BY LATE MORN. HELD OFF FOR NOW TO ADJUSTING POPS DOWNWARD OVR THE FAR N...SINCE LATEST 06Z SYNOPTIC MODELS STILL INDICATE A FEW HUNDREDTHS OF AN IN OF QPF OVR THIS PTN OF THE FA BETWEEN 12 AND 18Z (8AM-2PM) TODAY. ORGNL DISC: LATEST RADAR IMAGERY SHOWS THE BACK EDGE OF STEADY SNFL NOW SLIDING E OUT OF DOWNEAST AND CNTRL PTNS OF THE FA INTO NB PROV... BUT STILL HOLDING ACROSS NRN AND ERN AROOSTOOK COUNTY...AT LEAST FOR THE NEXT FEW HRS. AFTWRDS...WNW WINDS WILL DRAMATICALLY INCREASE ACROSS ALL OF THE REGION FOLLOWING THE PASSAGE OF AN ARCTIC FRONT WITHIN THE NEXT 1 TO 3 HRS. WIND GUSTS WILL BE REACHING MID TO HIGH END WIND ADV CRITERIA BY AFTN. HOWEVER... DUE TO MORE SNFL ACCUMULATION ACROSS THE N HLF OF THE FA...THE CONCERN IS MORE TOWARD BLSN...SO WE INCLUDED STRONG WINDS WITHIN THE WSW WNTR WX ADV STATEMENT. ACROSS THE SRN HLF OF THE FA WHERE THERE IS LESS ACCUMULATION...WE MENTION PATCHY BLSN WITHIN THE NPW WIND ADV STATEMENT. BOTH HDLNS ARE IN EFFECT UNTIL ERLY EVE... AFTER WHICH...WIND GUST POTENTIAL WILL SLOWLY DIMINISH OVRNGT. TEMPS WILL FALL SHARPLY ACROSS THE FA ERLY THIS MORN FOLLOWING THE ARCTIC FRONT...AND WILL NOT LIKELY MAKE MUCH GAIN THRU THE REMAINDER OF THE MORNG INTO ERLY AFTN...THEN FALL BY LATE AFTN...AS THE STRENGTHENING LATE MAR SUN ANGLE AND INCREASING DAYLENGTH IS ABOUT EVENLY MATCHED BY STRONG LLVL COLD ADVCN. MEANWHILE...THE BACK EDGE OF STEADY SN WILL NOT MAKE MUCH HEADWAY OUT OF XTRM NE PTNS OF THE FA DUE TO THE DEEPENING MARITIMES LOW...SO SCT SN SHWRS COULD AFFECT THE FAR N AND NE OF THE FA THRU THE REMAINDER OF THE DAY. INTERESTINGLY...TEMPS WILL CONT TO FALL THRU THE EVE...THEN LVL OFF LATE TNGT AND EVEN INCREASE BY DAYBREAK SPCLY ACROSS THE N HLF OF FA AS A WARM OCCLUSION FROM THE DEEPENING LOW WORKS IT WAY ALL THE WAY ARND THE N SIDE OF THE SYSTEM AND THEN BACK SW TOWARD THE GASPE PENINSULA. THIS WILL KEEP SCT SN SHWRS ACROSS THE NRN TWO THIRDS OF THE FA AND EVEN INTERMITTENT LGT SNFL GOING ACROSS THE FAR N AND NE WHILE CLDNSS SLIPS BACK TOWARD E CNTRL PTNS OF THE FA LATE TNGT. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... FOR MONDAY...WINDS AND CONTINUED COLD WILL BE THE PRIMARY FEATURES. HIGHS WILL MODERATE INTO THE 20S...BUT REMAIN FAR BELOW NORMAL. WINDS WILL GUST TOWARDS 35 MPH BY LATE MORNING IN NORTHERN ZONES. CLOUDY SKIES WILL PREVAIL EXCEPT IN THE DOWNSLOPE REGIONS AROUND BANGOR AND MUCH OF DOWN EAST. THE WINDS FINALLY DECREASE MONDAY NIGHT WITH RAPIDLY RISING SURFACE PRESSURE. LOWS WILL DROP INTO THE SINGLE DIGITS TO LOW TEENS. SUBZERO READINGS ARE POSSIBLE IN THE ALLAGASH WHERE WINDS WILL BE LIGHTEST. SUNSHINE WILL PROMOTE A NICE RECOVERY ON TUESDAY AND BRING HIGHS BACK ABOVE FREEZING FOR MOST LOCATIONS. MID TO UPPER 30S ARE PROBABLE FOR BANGOR AND DOWN EAST. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... A SHALLOW RADIATION INVERSION WILL DEVELOP ON TUESDAY NIGHT WITH WIDE VARIATIONS IN NIGHTTIME TEMPS. COLDER NORTHERN VALLEY COULD SEE SUBZERO READINGS WHILE HIGHER TERRAIN WILL STAY IN THE TEENS. THE SHALLOW INVERSION WILL BE QUICKLY ERASED WEDNESDAY MORNING AND TEMPERATURES WILL PUSH TOWARDS THE UPPER 30S AND LOWER 40S UNDER SUNNY SKIES. CLOUDS WILL INCREASE LATE AHEAD OF A LOW PROGGED TO TRACK ACROSS QUEBEC ON THURSDAY. THIS SYSTEM WILL BRING LIGHT AMOUNTS OF WARM ADVECTION SNOW WEDNESDAY NIGHT. THIS SNOW WILL QUICKLY MELT WITH HIGHS AGAIN REACHING THE MID 40S ON THURSDAY. THERE IS A LOT OF UNCERTAINTY AS TO HOW THINGS PLAY OUT AFTER THE WARM OCCLUSION ON WEDNESDAY NIGHT. A FRONTAL BOUNDARY IS EXPECTED TO BE STATIONARY JUST SOUTH OF THE FORECAST AREA THURSDAY. A COUPLE OF SOUTHERN STREAM SHORTWAVES ARE LIKELY TO MOVE NORTHEAST ALONG THE FRONTAL BOUNDARY. THESE SHORTWAVES HAVE THE POTENTIAL TO BRING QUITE A BIT OF RAIN. THE QUESTION IS EXACTLY WHERE THE BOUNDARY WILL SET UP AND WHICH SHORTWAVE WILL BE DOMINANT. FOR NOW...HAVE FOLLOWED AN ENSEMBLE APPROACH BEST MIRRORED BY THE OPERATIONAL ECMWF WHERE THE FIRST WAVE AFFECTS THE SOUTHERN THIRD OF THE FORECAST AREA THURSDAY AND THURSDAY EVENING WITH THE THREAT OF A HALF INCH OF RAIN AND WIDESPREAD FOG. BANGOR AND THE DOWN EAST REGION MAY STAY ABOVE THE FREEZING MARK FROM MIDDAY WEDNESDAY UNTIL FRIDAY NIGHT. THUS...THERE IS A THREAT THAT ICE WILL START MOVING AND JAMMING IN THE SOUTHERN PORTION OF THE FORECAST AREA BY THURSDAY NIGHT OR FRIDAY. IF THE SOUTHERN STREAM SHORTWAVE IS MORE POTENT THAN CURRENTLY EXPECTED...THERE COULD BE MORE WIDESPREAD FLOOD CONCERNS. A SECOND SHORTWAVE IS A THREAT TO AFFECT THE AREA LATER FRIDAY AND FRIDAY NIGHT...BUT WILL FORECAST IT TO MOVE SOUTH OF THE AREA FOR NOW. INSTEAD...WILL BRING A COLD FRONT ACROSS THE AREA ON FRIDAY THAT WILL BRING THE SUBFREEZING TEMPERATURES BACK TO BANGOR AND DOWN EAST ON FRIDAY NIGHT. THAT SAID...THERE IS LOW CONFIDENCE ON THE EVOLUTION AND MOVEMENT OF AN UPPER TROUGH MOVING OUT OF THE MIDWEST THURSDAY THROUGH FRIDAY NIGHT. THERE IS RISK OF SIGNIFICANT RAINFALL...SNOWMELT AND ICE JAMS DURING THIS PERIOD. THE BIGGEST RISK WILL BE IN THE SOUTHERN HALF OF THE FORECAST AREA WHERE TEMPERATURES WILL BE HIGHER. THE CHANCES OF HEAVIER RAINFALL WILL BE GREATER THERE AS WELL. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... NEAR TERM: IFR TO MVFR CONDITIONS XPCTD TDY ACROSS NRN TAF SITES IN FALLING SN TRANSITIONING TO BLSN AS FALLING SN IS REPLACED BY STRONG NW WINDS. DOWNEAST SITES WILL BE MSLY VFR TDY...WITH BRIEF MVFR IN BLSN POSSIBLE. NRN TAF SITES WILL THEN IMPROVE TO LOW VFR TO HI MVFR SC CLGS TNGT AS WIND GUSTS LOWER SOMEWHAT REDUCING BLSN WHILE DOWNEAST SITES BECOME STEADY VFR. SHORT TERM: MVFR CIGS FROM HUL NORTHWARD ON MONDAY. OTHERWISE VFR FOR ALL TERMINALS UNTIL WEDNESDAY NIGHT. EXPECT PREDOMINANT IFR WEDNESDAY NIGHT INTO THURSDAY WITH THE CHANCE OF FOG ON THURSDAY. && .MARINE... NEAR TERM: WILL CONT WITH THE CURRENT GLW AND FZGSPY ADV AS INITIALLY WINDS INCREASE ERLY THIS MORN BEHIND THE ARCTIC FRONT WITH THE FZGSPY ADV DELAYED A FEW HRS TO ALLOW COLDER AIR TO WORK OVR THE WATERS. BOTH HDLNS THEN REMAIN IN EFFECT THRU THE REMAINDER OF THE NEAR TERM THRU ALL OF SUN NGT. SHORT TERM: THE GALE AND FREEZING SPRAY WILL END LATER MONDAY MORNING AND GIVE WAY TO AN SCA THAT WILL CONTINUE INTO MONDAY EVENING. THE NEXT CONCERN WILL BE A STRONG SCA ON WEDNESDAY NIGHT INTO THURSDAY. SEAS COULD REACH 15 FEET IN A SOUTH SWELL. WINDS WILL BE THE LESSER CONCERN WITH THIS EVENT. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MEZ001>006-010. WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MEZ011-015>017- 029>032. MARINE...FREEZING SPRAY ADVISORY UNTIL 11 AM EDT MONDAY FOR ANZ050>052. GALE WARNING UNTIL 11 AM EDT MONDAY FOR ANZ050>052. && $$ NEAR TERM...DUDA/VJN SHORT TERM...MCW LONG TERM...MCW/BERDES AVIATION...DUDA/VJN/MCW MARINE...DUDA/VJN/MCW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
141 PM EDT SUN MAR 22 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 502 AM EDT SUN MAR 22 2015 DESPITE 850MB TEMPS AROUND -17C PER LATEST RAP ANALYSIS...THERE ARE NO LAKE EFFECT CLOUDS DEVELOPING OFF THE OPEN WATER OF NCNTRL LAKE SUPERIOR. EVEN OFF THE OPEN WATER EXTENDING FROM THE KEWEENAW TO MUNISING...THERE WAS A LITTLE BURST OF LES EARLIER IN THE NIGHT INTO ALGER COUNTY...BUT THAT HAS SINCE DISSIPATED. CONVERGENCE HAS RECENTLY STRENGTHENED OVER THAT OPEN WATER AREA AS A WIND SHIFT TO THE ENE IS PROGRESSING TOWARD THE MARQUETTE COUNTY SHORELINE WHERE LAND BREEZE IS EVIDENT. IN JUST IN THE LAST HR...THIS HAS RESULTED IN NEW LIGHT LES DEVELOPMENT OVER FAR ERN MARQUETTE COUNTY. OTHERWISE...AS OF 09Z...THAT IS IT FOR LES AND EVEN LAKE EFFECT CLOUDS OFF LAKE SUPERIOR. UPSTREAM 00Z SOUNDINGS AT KINL/CYPL TELL THE STORY AS NOT ONLY WAS THE AIR MASS DRY IN THE LOW TO MID LEVELS...BUT BOTH SOUNDINGS ALSO EXHIBITED THE HOSTILE FOR LES INVERTED V LOOK. WOULD EXPECT A CONTINUED UPTICK IN LES OFF SCNTRL LAKE SUPERIOR INTO FAR ERN MARQUETTE COUNTY AND ALGER COUNTY EARLY THIS MORNING AS WE APPROACH THE COOLEST PART OF THE DIURNAL CYCLE/MOST FAVORABLE TIME OF DAY FOR LES AT THIS TIME OF YEAR. THAT SAID...IT WON`T BE MORE THAN LIGHT SNOW SHOWERS AND FLURRIES WITH ANY ACCUMULATION UNDER 1 INCH. THE DISRUPTIVE EFFECT OF DAYTIME HEATING AT THIS TIME OF YEAR COMBINED WITH 850MB THERMAL TROF SHIFTING E WILL BRING AN END TO THE LIGHT LES EARLY THIS AFTN. ACROSS THE REST OF THE FCST AREA...EXPECT A PARTLY TO MOSTLY SUNNY DAY WITH HIGHS IN THE 20S ACROSS MOST OF THE N AND E TO THE 30S TOWARD THE MI/WI BORDER. SHORTWAVE MOVING ACROSS THE DAKOTAS TODAY AND INTO THE WRN GREAT LAKES TONIGHT WILL WEAKEN AS IT ENCOUNTERS INCREASINGLY CONFLUENT FLOW. MODELS SHOW THIS WAVE SPREADING PCPN ACROSS MN INTO WI. MODELS WHICH HAD PREVIOUSLY BROUGHT THE PCPN TO NEAR THE MI/WI BORDER TONIGHT HAVE TRENDED S WITH THE NRN EDGE OF THE PCPN. GIVEN THE CONFLUENT FLOW OVER THE UPPER LAKES...ESTABLISHED ARCTIC AIR AND CONTINUED DRY AIR EMANATING FROM THE SFC HIGH PRES AREA WHICH WILL BE SLOWLY DRIFTING E OF HERE...A DRY FCST IS THE WAY TO GO TONIGHT. MIN TEMPS TONIGHT COULD BE QUITE LOW...ESPECIALLY OVER THE ERN FCST AREA WHERE HIGH/MID CLOUDS WILL BE THINNEST AND WHERE THERE WILL BE LIGHT ENE WINDS OFF ONTARIO. EXPECT TRADITIONAL COLD SPOTS TO FALL TO NEAR 0F OR EVEN BLO. DEPENDING ON THICKNESS OF CLOUDS...SINGLE DIGITS ABOVE ZERO MAY BE COMMON IN THE INTERIOR WESTWARD INTO CNTRL UPPER MI. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 451 AM EDT SUN MAR 22 2015 AT 12Z MONDAY UPPER MI WILL STILL BE IN BETWEEN SYSTEMS. THE NEXT SHORTWAVE WILL BE OVER S MANITOBA. HIGH PRESSURE WILL STILL BE THE MAIN FEATURE...CENTERED OVER THE E HALF OF ONTARIO/E LAKE SUPERIOR/E UPPER MI. NOT EXPECTING MUCH OUT OF THE SHORTWAVE TO THE NW AS IT WORKS THROUGH A REGION OF PRETTY DRY AIR. THE PRECIP OVER NW MN MONDAY AFTERNOON IS EXPECTED TO ALL BUT DRY UP AS IT CROSSES MN AND W LAKE SUPERIOR. DID KEEP JUST A SMALL POCKET OF SLIGHT CHANCE POPS OVER W LAKE SUPERIOR MONDAY NIGHT...AND N LAKE SUPERIOR LATE MONDAY NIGHT/TUESDAY MORNING. THE SFC HIGH WILL SLIDE TO THE SE OVER FAR SE ONTARIO/S QUEBEC BY TUESDAY MORNING. LOOK FOR THE RETURN OF S WINDS ON TUESDAY...WITH 850MB TEMPS RISING TO C TO -2C BY THE END OF THE DAY. DOWNSLOPE AREAS AND LOCATIONS ALONG THE WI BORDER MAY SEE TEMPS IN THE UPPER 40S TO NEAR 50F...ESPECIALLY IF THE ANTICIPATED MOSTLY SUNNY SKY PANS OUT. SLOWED DOWN/BROUGHT MORE TEMPORAL DEFINITION TO THE INCOMING SNOW AND MIXED PRECIP LATE TUESDAY NIGHT. THERE IS STILL ENOUGH UNCERTAINTY IN THE FCST SOLUTIONS TO KEEP THE MENTION OF SEVERAL INCHES OF SNOW POSSIBLE IN THE HWO FOR LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING. EXPECT SFC LOWS FROM THE DAKOTAS AND E KS TUESDAY AFTERNOON TO MERGE ACROSS WI BY DAYBREAK WEDNESDAY. 850MB WINDS OUT OF THE S AT 40- 50KTS WILL BE OUT AHEAD OF THE LOW /ACROSS LAKE MI AT 12Z WEDNESDAY/...USHERING IN WARMER AIR. LOOKS LIKE A GOOD CHANCE OF MIXED PRECIP STILL OVER S CENTRAL AND E UPPER MI WEDNESDAY AFTERNOON...WHICH WILL MINIMIZE THE POTENTIAL FOR QUICKLY ACCUMULATING SNOW. DEF/LIKELY SNOW WILL EXIT WEDNESDAY AFTERNOON AS THE CONSOLIDATED LOW EXITS FROM E UPPER MI TO E ONTARIO. OTHERWISE...PRECIP SHOULD STAY MAINLY IN THE FORM OF SNOW NW OF A LINE FROM IRON TO MUNISING. MODERATE SNOW WILL BE POSSIBLE OVER THE FAR W...DIMINISHING TO A GOOD CHANCE AS STEADY N TO NW WINDS TAKE HOLD AND COLDER AIR PUSHES IN ON THURSDAY. 850MB TEMPS WILL FALL TO - 18 TO -22C THURSDAY AFTERNOON INTO EARLY FRIDAY MORNING. LIGHTER AND LESS FAVORABLE W TO SW WINDS SHOULD PUSH IN LATER FRIDAY...AS ANOTHER AREA OF HIGH PRESSURE SINKS IN FROM S CENTRAL CANADA. LOOKING FARTHER OUT...MODELS ARE HINTING AT ANOTHER SYSTEM FOR THE END OF THE WEEKEND. STAY TUNED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 140 PM EDT SUN MAR 22 2015 VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AS A HIGH PRESSURE RIDGE REMAINS OVER THE AREA. THIS WILL LEAD TO LIGHT WINDS AFTER DIURNAL MIXING DIMINISHES THIS EVENING. A DISTURBANCE MOVING THROUGH SOUTHERN MINNESOTA/WISCONSIN WILL STREAM HIGH CLOUDS ACROSS UPPER MICHIGAN LATER THIS EVENING INTO MONDAY. THE CLOUDS ARE EXPECTED TO BE THE THICKEST OVER THE SOUTHWEST HALF OF UPPER MICHIGAN. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 502 AM EDT SUN MAR 22 2015 JUST AHEAD OF A HIGH PRES RIDGE EXTENDING SE OVER WRN LAKE SUPERIOR...NW WINDS OVER FAR ERN LAKE SUPERIOR WILL PROBABLY INCREASE TO 15-25KT TODAY. OTHERWISE...WINDS WILL BE UNDER 20KT. WINDS WILL THEN BE UNDER 20KT ACROSS THE LAKE TONIGHT AS THE HIGH PRES RIDGE DRIFTS E. WINDS SHOULD GENERALLY REMAIN UNDER 20KT MON INTO EARLY TUE AS PRES GRADIENT REMAINS WEAK. ATTENTION THEN TURNS TO DEEPENING LOW PRES WHICH WILL TRACK FROM THE CNTRL PLAINS TUE TO EASTERN UPPER MI WED AFTN. AHEAD OF THIS SYSTEM...SE TO E WINDS WILL INCREASE TUE NIGHT TO 15-25KT ACROSS MUCH OF LAKE SUPERIOR. WINDS WILL THEN VEER AROUND TO THE N WED/THU. WHILE 15-25KT WINDS WILL PROBABLY BE COMMON...WILL NEED TO WATCH FOR STRONGER WINDS UP TO 30KT AND POTENTIALLY UP TO GALE FORCE AT SOME POINT WED INTO EARLY THU FOR PARTS OF LAKE SUPERIOR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...SRF MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1242 PM CDT SUN MAR 22 2015 .UPDATE... ISSUED AT 1241 PM CDT SUN MAR 22 2015 LIGHT SNOW ALONG AND EAST OF A LINE FROM HARVEY TO BISMARCK SHOULD END FROM NORTHWEST TO SOUTHEAST THROUGH THE AFTERNOON. TEMPERATURES IN THE FAR WEST HAVE RISEN INTO THE 40S...BUT IT APPEARS TEMPERATURES CLOSER TO THE MISSOURI RIVER WILL BE SLOW TO RISE AND HAVE LOWERED EXPECTED MAXIMUM TEMPERATURES THERE. UPDATE ISSUED AT 1053 AM CDT SUN MAR 22 2015 MAIN UPDATE TO END THE FREEZING RAIN ADVISORY SOUTHWEST. ICY ROADS WILL LINGER THERE UNTIL TEMPERATURES RISE ABOVE FREEZING. ALSO INCREASED CHANCES OF LIGHT SNOW FAR SOUTHWEST FOR THE AFTERNOON HOURS. UPDATED HOURLY TEMPERATURE TRENDS. UPDATED FORECASTS WILL BE ISSUED SHORTLY. UPDATE ISSUED AT 940 AM CDT SUN MAR 22 2015 MAIN CONCERN IS PRECIPITATION TYPE ACROSS THE SOUTHWEST AND SOUTH CENTRAL. FEW OBSERVATION POINTS THIS AREA. RADAR ECHOES HAD EXPANDED FROM GRANT AND SIOUX COUNTY INTO EMMONS/LOGAN/MCINTOSH COUNTIES AND FEAR WAS THAT FREEZING RAIN MIGHT BE OCCURRING THERE. BRIGHT BAND OF REFLECTIVITY FROM HETTINGER TO SOUTHERN GRANT INTO SIOUX COUNTY INTO LOGAN/MCINTOSH...WITH RADAR SUGGESTING SLEET. REPORTS WEST IN SLOPE COUNTY AND HETTINGER WERE FREEZING RAIN...JUST RECENTLY GOT REPORTS OF SNOW NEAR THE CORNER OF EMMONS/LOGAN/MCINTOSH COUNTY. THUS APPEARS FREEZING RAIN WAS CHANGING TO SNOW EAST OF THE MISSOURI RIVER. MAIN BAND OF PRECIPITATION WAS MOVING SOUTH AND EAST...AND BY 11 AM CDT/10 AM MDT THE BULK OF PRECIPITATION SHOULD BE SOUTH AND EAST OF OUR AREA. THUS WILL KEEP THE FREEZING RAIN ADVISORY GOING FOR SOUTHWESTERN NORTH DAKOTA UNTIL SAID TIME. OTHER CHANGE WAS THAT SURFACE TEMPERATURES IN THE SOUTHWEST WERE NOT RISING AS QUICKLY AS FORECAST. HOWEVER EXPECT RISING TEMPERATURES TO COMMENCE WITHIN AN HOUR OR TWO AND BEGIN RISING INTO THE 40S BY LATE MORNING...AS WINDS IN THE FAR WEST BECOME SOUTH AND THEN TURN WEST BRINGING WARMER AIR INTO THE REGION. UPDATE ISSUED AT 705 AM CDT SUN MAR 22 2015 MADE ONLY MINOR ADJUSTMENTS TO THE FORECAST BY BLENDING IN CURRENT CONDITIONS. AREA RADARS STILL SHOW LIGHT PRECIPITATION MOVING ACROSS WESTERN AND CENTRAL NORTH DAKOTA...WITH THE LATEST MESO- SCALE MODELS FOCUSING MOST OF THEIR ATTENTION ON THE PRECIPITATION ACROSS SOUTHERN NORTH DAKOTA. THE FREEZING RAIN ADVISORY STILL LOOKS WELL PLACED AND WILL LEAVE AS IS. UPDATE ISSUED AT 512 AM CDT SUN MAR 22 2015 QUICK UPDATE TO ISSUE A FREEZING RAIN ADVISORY FOR THE SOUTHWEST CORNER. JUST HAD A REPORT OF ICY CONDITIONS NEAR HEBRON ON I94 WITH AN ACCIDENT AND SEMI TRUCKS STRUGGLING TO DRIVE UP HILLS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 414 AM CDT SUN MAR 22 2015 FORECAST HIGHLIGHTS AND CHALLENGES IN THE SHORT TERM PERIOD WILL BE THE THREAT FOR FREEZING PRECIPITATION ACROSS THE SOUTHWEST THIS MORNING...AND HOW PRECIPITATION EVOLVES EASTWARD. CURRENTLY...ACTIVE ZONAL FLOW ALOFT WITH A POTENT SHORT WAVE MOVING EAST INTO SOUTH CENTRAL CANADA AND ANOTHER MORE SUBTLE/EMBEDDED FEATURE MOVING EAST ACROSS NORTHERN WYOMING/SOUTHEASTERN MONTANA. ASSOCIATED SURFACE LOWS OVER SOUTHERN SASKATCHEWAN AND EASTERN WY/SOUTHWESTERN SD RESPECTIVELY. THE SOUTHERN MOST WAVE IS OUR MAIN CONCERN...GENERATING PRECIPITATION FROM SOUTHEASTERN MONTANA EAST TO ACROSS SOUTHWESTERN NORTH DAKOTA. THERMAL PROFILES AND SFC TEMPERATURES INDICATING LIGHT FREEZING RAIN IS LIKELY FALLING. MADE A FEW CALLS TO THE SOUTHWEST WHICH INDICATED NO IMPACTS AS SO FAR THE LIGHT FREEZING PRECIP IS ONLY TRACING OUT. A VERY DRY EASTERLY FLOW IS KEEPING THE BOUNDARY LAYER RATHER DRY FROM THE SURFACE UP TO 5-7K FT AGL...SO ANY MOISTURE REACHING THE GROUND SHOULD BE LIMITED. WILL MAINTAIN LIKELY POPS SOUTHWEST INTO SOUTH CENTRAL. HAVE A SPECIAL WEATHER STATEMENT OUT NOW FOR THE FREEZING RAIN POTENTIAL...AND WILL CONTINUE WITH THIS UNLESS WE HEAR OF MORE IMPACTS AND A FREEZING RAIN ADVISORY BECOMES NEEDED. MORE RADAR RETURNS ACROSS THE NORTH...BUT AGAIN WITH CLOUD BASES AT ROUGHLY 8-10K AGL...ANTICIPATE LITTLE IS REACHING THE GROUND SO WILL KEEP POPS BELOW LIKELY THERE. MODELS HAVING A HARD TIME THIS MORNING WITH EACH RUN OF THE HRRR AND NAM MODELS DIFFERENT. BASICALLY WENT WITH A BLEND WHICH FOLLOWS THE 00Z ECMWF AND LATEST 06Z NAM RATHER WELL. THIS CONFINES HIGHER POPS THIS MORNING TO MY SOUTHERN COUNTIES...ALONG TO SOUTH OF INTERSTATE 94. MAIN THREAT FOR FREEZING RAIN WILL REMAIN WEST OF THE MISSOURI RIVER ACROSS MY SOUTHWEST THROUGH MID MORNING...WITH THERMAL PROFILES SUGGESTING ALL SNOW TO THE EAST. SURFACE FRONTAL BOUNDARY MOMENTARILY STALLS ACROSS THE WEST THIS AFTERNOON...WITH A WESTERLY WIND TO THE WEST AND SOUTHERLY WIND TO THE EAST. NAM AND RAP ARE INDICATING POSSIBLE STRATUS DEVELOPMENT ALONG TO EAST OF THE BOUNDARY LATER TODAY INTO THIS EVENING AS THE SOUTH/SOUTHEASTERLY FLOW TRANSPORTS MOISTURE NORTH. THUS WILL KEEP SKY COVER ELEVATED ABOVE MOSTLY SUNNY/MOSTLY CLEAR. CONFIDENCE NOT HIGH WITH THIS PLAYING OUT WITH MODELS STRUGGLING THE PAST FEW RUNS. AFOREMENTIONED STRONG SHORT WAVE CUTTING EAST ACROSS SOUTH CENTRAL CANADA WILL TURN SOUTHEAST AND MOVE INTO FAR NORTHEASTERN ND/NORTHERN MINNESOTA THIS SUNDAY NIGHT. PRECIPITATION IN THE FORM OF SNOW MAY GRAZE MY FAR NORTHEAST SO WILL MAINTAIN A LOW POP THERE TONIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 414 AM CDT SUN MAR 22 2015 THE PRIMARY CONCERN IN THE LONG TERM PERIOD WILL BE THE POTENT STORM MONDAY NIGHT INTO TUESDAY. THE LATEST MODEL SUITE CONTINUES TO ADVERTISE A POTENT STORM SYSTEM ACROSS THE NORTHERN PLAINS MONDAY NIGHT INTO TUESDAY. DETAILS REGARDING THE EXACT TRACK OF THE SYSTEM REMAIN ELUSIVE WITH THE 00Z GFS AND ECMWF STILL SHOWING DIFFERENCES...AND LARGE SPREAD INDICATED BY THE GEFS. THE ECMWF AND GFS BOTH SUGGEST TWO SURFACE LOWS WILL DEVELOP...HOWEVER THEY DIFFER ON THE PROGRESSION OF THE NORTHERN MOST LOW. THE ECMWF KEEPS THE LOWS SEPARATE WITH ONE TRACKING INTO CANADA...WHILE THE GFS MERGES THE LOWS IN MINNESOTA / WISCONSIN. HAVE AGAIN GONE WITH A BLENDED MODEL SOLUTION DUE TO THE UNCERTAINTY. THIS MAINTAINS SOME CONSISTENCY IN THE FORECAST WITH WARM AIR AND RAIN EXPECTED ACROSS MUCH OF CENTRAL AND WESTERN NORTH DAKOTA DURING THE MORNING AND AFTERNOON TUESDAY. THE EXCEPTION COULD BE THE FAR NORTH AND WEST WHERE COLDER AIR MAY FAVOR SNOW. COLD AIR ARRIVES BEHIND THE LOW TUESDAY NIGHT...WHICH SUPPORTS A THERMAL PROFILE TRANSITIONING TO SNOW ACROSS THE FORECAST AREA. CONFIDENCE IN PRECIPITATION AND / OR SNOW AMOUNTS REMAINS LOW DUE TO THE LARGE DIFFERENCES IN MODEL SOLUTIONS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 124 PM CDT SUN MAR 22 2015 LIGHT SNOW TO CONTINUE EAST OF A LINE FROM HARVEY TO BISMARCK THIS AFTERNOON...ENDING FROM WEST TO EAST. KJMS TO SEE S- IN MVFR CIGS FROM 20Z-23Z. OTHERWISE MVFR CIGS FROM HARVEY TO KBIS AND EASTWARD...BECOMING VFR DURING THIS AFTERNOON. RETURN OF MVFR CIGS EXPECTED BY AROUND 02Z/03Z WITH SOUTHERLY WINDS REMAINING AT KBIS/KJMS/KMOT. A COLD FRONT TO MOVE INTO KISN FROM THE NORTH AROUND 03Z-06Z TO BRING MVFR CIGS...REACHING KDIK 09Z-12Z. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JV SHORT TERM...NH LONG TERM...CK AVIATION...JV
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1238 PM CDT SUN MAR 22 2015 .UPDATE... ISSUED AT 1237 PM CDT SUN MAR 22 2015 AFTER WATCHING THE STREAMING WEB CAM AT OAKES JUST OUTSIDE OF THE SOUTHWESTERN CWA...FLAKES HAVE STARTED TO FALL AFTER SEVERAL HOURS OF RADAR RETURNS OVERHEAD. NOTHING ACCUMULATING SO FAR...THE RAP AND HRRR STILL HAVE SOME QPF GETTING INTO OUR FAR SOUTHERN CWA THIS AFTERNOON. WILL CONTINUE TO KEEP HIGH POPS IN THE FAR SOUTH BUT TIGHTENED THE NORTHERN EDGE OF IT AND LOWERED SNOW AMOUNTS AS IT SEEMS THAT THE BULK OF THE SNOW WILL BE TO OUR SOUTH. TWEAKED TEMPS A BIT...RAISING THEM IN SOME AREAS AND LOWERED THEM IN OTHERS. THE NORTHEASTERN COUNTIES HAVE STAYED SUNNY AND ARE FINALLY GETTING UP TO THE LOWER 30S. THE TEMPS ARE ALSO IN THE LOWER 30S IN THE SOUTHWESTERN COUNTIES WITH CLOUDS BUT THINK THERE MAY BE A BIT OF A DROP AS WE GET EVAPORATIVE COOLING AS THE PRECIP STARTS TO MOVE INTO THE REGION. UPDATE ISSUED AT 1001 AM CDT SUN MAR 22 2015 BAND OF PRECIP CONTINUES TO MOVE EASTWARD TOWARDS OUR SOUTHWESTERN COUNTIES. HOWEVER...WEB CAMS NEAR WISHEK WHICH HAS HAD RADAR RETURNS MOVING OVERHEAD FOR THE LAST FEW HOURS SHOW THAT NOT MUCH IS REACHING THE GROUND SO FAR. MODEL SOUNDINGS CONTINUE TO SHOW A DRY LAYER NEAR THE SFC WHICH DOES NOT REALLY SATURATE UNTIL WELL INTO THE AFTERNOON HOURS. CONTINUED TO KEEP SOME LIKELY POPS IN THE FAR SOUTHERN COUNTIES FOR THIS AFTERNOON AS WE WILL NOT SEE MUCH BEFORE THEN...BUT WILL HAVE TO WATCH TO SEE HOW THE BATTLE BETWEEN DRY AIR AND FRONTOGENESIS UNFOLDS AND MAKE ADJUSTMENTS AS NEEDED. UPDATE ISSUED AT 650 AM CDT SUN MAR 22 2015 BAND OF PRECIP IS SETTING UP ACROSS SOUTHERN NORTH DAKOTA...AND LATEST HI-RES GUIDANCE INDICATES THIS BAND WILL AFFECT THE FAR SOUTHERN FA BY LATER THIS MORNING AND INTO THE AFTERNOON HOURS. STRONGEST MESOSCALE FORCING WILL BE SOUTH OF THIS AREA...BUT CURRENT INDICATIONS SUGGEST AND INCH OR TWO OF SNOW MAY OCCUR TODAY ACROSS THIS AREA. TO THE NORTH...GIVEN THE DRY LOW LEVEL AIRMASS IN PLACE AND WEAKER FORCING WENT WITH A DRY FORECAST (EXCEPT THE CANDO AREA FOR THIS MORNING WHERE RADAR INDICATES A STRONGER AREA OF PRECIP MAY PROVIDE FLURRIES OR VERY LIGHT SNOW FOR A BRIEF TIME). && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 330 AM CDT SUN MAR 22 2015 SNOW CHANCES AND AMOUNTS WILL BE THE CHALLENGE. 00Z MODELS IN DECENT AGREEMENT...ALTHOUGH THERE ARE SOME DIFFERENCES TODAY. RIDGING REMAINS IN PLACE ACROSS THE REGION WITH DRY LOW LEVEL EASTERLY FLOW. MODEL TRENDS INDICATE LESS INTERACTION BETWEEN NORTHERN AND SOUTHERN UPPER WAVES...LEADING TO FAR LESS QPF ACROSS THE WESTERN FA TODAY. IN FACT...THE LATEST HRRR AND RAP GUIDANCE INDICATES THAT QPF WILL REMAIN OUTSIDE OF THE FA WITH STRONGER RIDGING/MORE DRY AIR. TRENDED THE FORECAST IN THIS DIRECTION...WITH MAYBE AN INCH OR TWO OF SNOW ACROSS THE FAR SOUTHERN FA. WILL CONTINUE TO MONITOR TRENDS AND MAY EVENTUALLY REMOVE ALL POPS FOR TODAY. WITH THIS...MODELS ARE TRENDING WARMER TODAY (THINNER CLOUD COVER)...AND FOLLOWED THIS TREND IN THE FORECAST. TONIGHT...THE NORTHERN UPPER WAVE IS QUITE STRONG...AND MODELS HAVE BEEN CONSISTENT SPREADING SNOW INTO PARTS OF THE NORTHERN FA (WITH AN INCH OR TWO POSSIBLE). MONDAY...REGION WILL BE BETWEEN SYSTEMS ALONG WITH WARM AIR ADVECTION AHEAD OF THE NEXT SYSTEM. SHOULD BE A RELATIVELY QUIET DAY WITH MAX TEMPS APPROACHING OR INTO THE 40S. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAR 22 2015 MONDAY NIGHT-TUESDAY NIGHT...STRONGER SYSTEM WILL AFFECT THE REGION...MOST LIKELY LATER TUESDAY INTO TUESDAY NIGHT. CONFIDENCE IS HIGH THAT SOMETHING IS GOING TO OCCUR...ALTHOUGH MODELS ARE ALL OVER THE PLACE WITH DETAILS SO EXACTLY WHAT OCCURS IS HIGHLY QUESTIONABLE. GENERALLY...THE REGION WILL BE WITHIN AN INVERTED TROUGH WITH RAIN EVENTUALLY CHANGING TO SNOW. SOME MODELS ARE INDICATING OVER A FOOT OF SNOW...WITH OTHERS FAR LESS (OR ALMOST NOTHING). MUCH WILL DEPEND ON HOW THE SYSTEM EVOLVES...AND WHEN/WHERE THE SOUTHERN SFC LOW STRENGTHENS (WHICH WILL INFLUENCE THE STRENGTH OF THE INVERTED TROUGH AND THUS QPF AMOUNTS). FOR NOW...THE BEST THING TO SAY IS RAIN CHANGING TO SNOW WITH SOME ACCUMULATIONS POSSIBLE. WEDNESDAY-SATURDAY...THE BACKSIDE OF THE FULLY DEVELOPED CLOSED- LOW SYSTEM OVER WISCONSIN AND MOVING EASTWARD WILL BRING AN END TO THE PRECIPITATION OVER WEST-CENTRAL MINNESOTA WITH THE NORTHERLY WINDS ADVECTING IN SOME COOLER DAYTIME TEMPERATURES IN THE 30S AND LOWS IN THE TEENS FOR WEDNESDAY. A SURFACE HIGH PRESSURE SYSTEM WILL BE IN PLACE OVER THE AREA BY THURSDAY AHEAD OF A BUILDING UPPER-AIR RIDGE ON THE WEST COAST. THAT HIGH WILL BE SHIFTING TO THE EAST WITH SOME SOUTHERLY WINDS ON ITS BACKSIDE BRINGING IN SOME WARMER AIR FOR FRIDAY AND SATURDAY. HOWEVER...AN EMBEDDED UPPER-AIR SHORT WAVE EMBEDDED IN THE NORTHWEST FLOW FROM WESTERN RIDGE WILL BRING GOOD CHANCES FOR WEEKEND PRECIPITATION AS ANOTHER SURFACE LOW SPINS UP TO TRAVERSE THE REGION OVER THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1237 PM CDT SUN MAR 22 2015 SFC RIDGE AXIS CURRENTLY LIES ACROSS PORTIONS OF WRN MINNESOTA...AND IS EXPECTED TO SLOWLY DRIFT E THRU THE PERIOD. SFC DEW POINTS DRY WITH VALUES IN THE SINGLE DIGITS ACROSS MOST OF THE AREA...WITH THE DRY AIR EXTENDING UP THRU AROUND 8-10 KFT. THE DRY LOW LEVELS WILL PERSIST THRU TODAY AND TONIGHT. HOWEVER...A WEAK UPPER LEVEL DISTURBANCE IS EXPECTED TO CROSS THE NRN PART OF THE AREA OVERNIGHT STARTING AROUND THE 08-12Z TIME FRAME...WITH INCREASED MOISTURE AND A CHANCE FOR MVFR CIGS AND -SN MAINLY AT DVL...GFK AND TVF. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JR SHORT TERM...TG LONG TERM...TG/LUKES AVIATION...JR
AREA FORECAST DISCUSSION
NWS NORMAN OK
600 PM CDT SUN MAR 22 2015 .AVIATION... LOW CLOUDS AND FOG ARE EXPECTED OVER MUCH OF THE WESTERN HALF OF OKLAHOMA EARLY MONDAY. THE MVFR AND IFR SHOULD CLEAR BY 231700 FROM EAST TO WEST. GUSTY SOUTH WINDS WILL DEVELOP MONDAY AFTERNOON. && .PREV DISCUSSION... /ISSUED 224 PM CDT SUN MAR 22 2015/ DISCUSSION... LOW CLOUDS WILL CONTINUE TO ERODE THROUGH THE AFTERNOON ACROSS SOUTHWEST OKLAHOMA AND NORTH TEXAS. NAM AND RAP SOUNDINGS SUGGEST THAT FOG...SOME DENSE...WILL REFORM AGAIN TONIGHT...ESPECIALLY ACROSS WEST CENTRAL...SOUTHWEST OKLAHOMA AND NORTH TEXAS. ON MONDAY...AN ISOLATED STORM OR TWO MAY DEVELOP IN FAR WESTERN OKLAHOMA NEAR A DRYLINE. BETTER CHANCES WILL REMAIN NORTH AND EAST OF THIS AREA MONDAY NIGHT AND EARLY TUESDAY NORTH OF A WARM FRONT IN KANSAS. EARLY TUESDAY...DRIER AIR WILL PUSH INTO WESTERN PARTS OF OKLAHOMA AND NORTH TEXAS...AS A SHORTWAVE TROUGH MOVES ACROSS THE CENTRAL PLAINS. BREEZY NORTHWEST TO WEST WINDS TUESDAY AFTERNOON AND RATHER LOW HUMIDITY WILL INCREASE THE CHANCE OF WILDFIRES. FARTHER EAST...THUNDERSTORMS WILL BE POSSIBLE...MAINLY IN EASTERN OKLAHOMA. MOISTURE WILL QUICKLY RETURN ON WEDNESDAY AHEAD OF ANOTHER FRONT. STORM CHANCES WILL INCREASE BY WEDNESDAY AFTERNOON...ESPECIALLY ALONG AND SOUTHEAST OF INTERSTATE 44. INSTABILITY AND SHEAR WILL SUPPORT SEVERE STORMS...BUT FAVOR LOWER DEWPOINT VALUES GFS/EC COMPARED WITH NAM12. HAIL...STRONG WINDS AND HEAVY RAIN WILL BE THE IMPACTS WITH STORMS WEDNESDAY AFTERNOON AND EVENING. COOLER AND DRIER AIR WILL FILTER INTO THE SOUTHERN PLAINS THURSDAY INTO FRIDAY. ANOTHER TROUGH WILL MOVE ACROSS THE AREA ON FRIDAY. ASSOCIATED CLOUD COVER SHOULD KEEP TEMPERATURES FROM FALLING TO OR BELOW FREEZING IN NORTHERN OKLAHOMA EARLY FRIDAY MORNING. MANY AREAS HAVE BEEN ABOVE FREEZING FOR AN EXTENDED PERIOD. EARLY SATURDAY MORNING...A FEW AREAS ACROSS THE NORTHERN HALF OF THE STATE MAY SEE A LIGHT FREEZE. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 50 77 59 80 / 0 0 0 0 HOBART OK 49 80 54 81 / 0 0 0 0 WICHITA FALLS TX 49 81 58 84 / 0 0 0 0 GAGE OK 46 82 49 79 / 0 10 0 0 PONCA CITY OK 48 78 57 79 / 0 10 20 0 DURANT OK 47 74 55 79 / 0 0 0 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 23/09/09
AREA FORECAST DISCUSSION
NWS NORMAN OK
224 PM CDT SUN MAR 22 2015 .DISCUSSION... LOW CLOUDS WILL CONTINUE TO ERODE THROUGH THE AFTERNOON ACROSS SOUTHWEST OKLAHOMA AND NORTH TEXAS. NAM AND RAP SOUNDINGS SUGGEST THAT FOG...SOME DENSE...WILL REFORM AGAIN TONIGHT...ESPECIALLY ACROSS WEST CENTRAL...SOUTHWEST OKLAHOMA AND NORTH TEXAS. ON MONDAY...AN ISOLATED STORM OR TWO MAY DEVELOP IN FAR WESTERN OKLAHOMA NEAR A DRYLINE. BETTER CHANCES WILL REMAIN NORTH AND EAST OF THIS AREA MONDAY NIGHT AND EARLY TUESDAY NORTH OF A WARM FRONT IN KANSAS. EARLY TUESDAY...DRIER AIR WILL PUSH INTO WESTERN PARTS OF OKLAHOMA AND NORTH TEXAS...AS A SHORTWAVE TROUGH MOVES ACROSS THE CENTRAL PLAINS. BREEZY NORTHWEST TO WEST WINDS TUESDAY AFTERNOON AND RATHER LOW HUMIDITY WILL INCREASE THE CHANCE OF WILDFIRES. FARTHER EAST...THUNDERSTORMS WILL BE POSSIBLE...MAINLY IN EASTERN OKLAHOMA. MOISTURE WILL QUICKLY RETURN ON WEDNESDAY AHEAD OF ANOTHER FRONT. STORM CHANCES WILL INCREASE BY WEDNESDAY AFTERNOON...ESPECIALLY ALONG AND SOUTHEAST OF INTERSTATE 44. INSTABILITY AND SHEAR WILL SUPPORT SEVERE STORMS...BUT FAVOR LOWER DEWPOINT VALUES GFS/EC COMPARED WITH NAM12. HAIL...STRONG WINDS AND HEAVY RAIN WILL BE THE IMPACTS WITH STORMS WEDNESDAY AFTERNOON AND EVENING. COOLER AND DRIER AIR WILL FILTER INTO THE SOUTHERN PLAINS THURSDAY INTO FRIDAY. ANOTHER TROUGH WILL MOVE ACROSS THE AREA ON FRIDAY. ASSOCIATED CLOUD COVER SHOULD KEEP TEMPERATURES FROM FALLING TO OR BELOW FREEZING IN NORTHERN OKLAHOMA EARLY FRIDAY MORNING. MANY AREAS HAVE BEEN ABOVE FREEZING FOR AN EXTENDED PERIOD. EARLY SATURDAY MORNING...A FEW AREAS ACROSS THE NORTHERN HALF OF THE STATE MAY SEE A LIGHT FREEZE. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 50 77 59 80 / 0 0 0 0 HOBART OK 49 80 54 81 / 0 0 0 0 WICHITA FALLS TX 49 81 58 84 / 0 0 0 0 GAGE OK 46 82 49 79 / 0 10 0 0 PONCA CITY OK 48 78 57 79 / 0 10 20 0 DURANT OK 47 74 55 79 / 0 0 0 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS PORTLAND
245 PM PDT SUN MAR 22 2015 .SYNOPSIS...A COLD FRONT IS MOVING ACROSS THE AREA THIS EVENING. COOLER AND MORE SHOWERY WEATHER EXPECTED TONIGHT AND MONDAY AS A COLDER TROUGH MOVES OVER THE PACIFIC NW. THUNDERSTORMS ARE POSSIBLE WITH THESE SHOWERS AS WELL AS THE LOWERING OF SNOW LEVELS... AND ACCUMULATING SNOW AT THE CASCADE PASSES. ANOTHER DISTURBANCE WILL MOVE THROUGH MONDAY NIGHT AND TUESDAY FOR MORE MORE RAIN AND A BETTER CHANCE FOR MOUNTAIN SNOW. A WARM FRONT WILL BRUSH THE AREA TUESDAY NIGHT AND WEDNESDAY AS AN UPPER RIDGE BUILDS OFFSHORE. THE UPPER RIDGE WILL MOVE ONSHORE WEDNESDAY NIGHT AND THURSDAY AND POSSIBLY CONTINUE THROUGH NEXT WEEKEND. && .SHORT TERM...TONIGHT THROUGH WEDNESDAY...A COLD FRONT IS SPREADING LIGHT RAIN ACROSS NW OR AND SW WA THIS AFTERNOON AND EVENING. SNOW LEVELS IS BETWEEN 5500 AND 6000 FEET THIS AFTERNOON...BUT WILL LOWER TO BETWEEN 4000 AND 5000 FEET BEHIND THE FRONT TONIGHT. SHOWERS WILL DECREASE WHEN THE COLDER AIR ARRIVES...BUT ELEVATIONS ABOVE 4500 FEET MAY SEE A COUPLE OF INCHES OF NEW SNOW. COLDER AND MORE UNSTABLE AIR MOVES IN LATE TONIGHT AS A NEGATIVELY TILTED UPPER TROUGH APPROACHES. THIS TROUGH WILL ENHANCE SHOWERS THAT MAY HAVE SOME THUNDERSTORMS EMBEDDED IN THEM. THERE HAS BEEN A COUPLE OF LIGHTNING STRIKES DETECTED IN SHOWERS NEAR THIS TROUGH THIS AFTERNOON. SNOW LEVELS WILL LOWER EVEN MORE WHEN THE TROUGH MOVES OVER THE AREA MONDAY MORNING...AND ARE EXPECTED TO DROP TO BETWEEN 3000 AND 4000 FEET. SHOWERS FROM THIS TROUGH WILL PERSIST THROUGH MONDAY AFTERNOON AND LIGHT SNOW ACCUMULATIONS OF 1 TO 3 INCHES. THE THIRD SYSTEM WILL BE A LITTLE MORE INTERESTING AS MODELS ARE FORECASTING A 1012 MB SURFACE LOW TO MOVE ONTO THE CENTRAL OREGON COAST MONDAY NIGHT.THERE WILL BE MOVE AVAILABLE MOISTURE WITH THIS SYSTEM WITH MODELS FORECASTING LAYERED PRECIPITABLE WATER VALUES JUST UNDER AN INCH. THE SNOW LEVELS WILL STILL BE ON THE LOW SIDE...AROUND 3500 FEET AND THE CASCADES WILL HAVE A BETTER CHANCE FOR MORE ACCUMULATING SNOW MONDAY NIGHT. THE CURRENT TRACK OF THIS LOW SUGGESTS THAT THE QPF WILL BE GREATER FOR AREAS SOUTH OF SALEM...AND EXPECT THE CENTRAL AND NORTHERN OREGON CASCADES TO SEE HIGHER SNOW ACCUMULATIONS THAN THE SOUTH WASHINGTON CASCADES. 4 TO 10 INCHES OF NEW SNOW ARE POSSIBLE FOR THE OREGON CASCADES FROM MONDAY EVENING THROUGH TUESDAY MORNING...AND 2 TO 6 INCHES FOR THE SOUTH WASHINGTON CASCADES. ARE POSSIBLE DOWN TO OR JUST BELOW THE CASCADE PASSES. THE LOW WILL PUSH EAST OF THE CASCADES LATE TUESDAY MORNING AND SHOWERS WILL QUICKLY END. SNOW LEVELS WILL RAPIDLY RISE TUESDAY AS A WARM FRONT BRUSHES JUST WEST OF OREGON. THE TAIL END OF THE WARM FRONT WILL BRUSH OVER SW WASHINGTON TUESDAY NIGHT AND WEDNESDAY. AVAILABLE MOISTURE WILL REMAIN HIGH WITH THIS WARM FRONT. THE MODELS CURRENTLY FORECAST THAT MOST OF THE MOISTURE AND RESULTANT RAIN WILL REMAIN NORTH OF THE PORTLAND FORECAST AREA...BUT EXTREME SW WASHINGTON MAY GET CLIPPED WITH HEAVY RAIN TUESDAY NIGHT THROUGH WEDNESDAY. TJ .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...A RIDGE OF HIGH PRESSURE STARTS TO BUILD OVER THE PACNW WEDNESDAY NIGHT...PUSHING ANY LINGERING SHOWERS OFF TO THE EAST AND OUT OF OUR AREA BY THURSDAY MORNING. THERE HAS BEEN SIGNIFICANT INCONSISTENCY ON HOW STRONG THIS RIDGE GETS BETWEEN MODEL RUNS AND THIS INCREASES UNCERTAINTY FOR OUR WEATHER THROUGH THE EXTENDED PERIOD. MODELS HAVE GENERALLY BEEN FORECASTING A FAIRLY SIGNIFICANT RIDGE BUILDING BRINGING BACK AN DRY WARM WEATHER THROUGH THE END OF THE WEEKEND...SO HAVE LEANED TOWARD THIS SCENARIO. THERE IS A CHANCE THAT THE LOW PRESSURE SYSTEM THAT RIDES OVER THE RIDGE AS IT MOVES ON-SHORE FRIDAY NIGHT OR EARLY SATURDAY COULD DROP FURTHER SOUTH BRINGING RAIN BACK TO OUR AREA FOR SATURDAY. EITHER WAY...THE RIDGE LOOKS LIKELY TO REBUILD OVER THE PACNW SUNDAY INTO MONDAY. -MCCOY && .AVIATION...COLD FRONT HAS PASSED THE COAST AND WILL CONTINUE TO MOVE INLAND THIS AFTERNOON AND EVENING. EXPECT SCATTERED SHOWERS TO CONTINUE TO BRIEF SPURTS OF MVFR CIG AND/OR VIS THROUGH THE EVENING. IT STILL LOOKS LIKE THERE ARE SOME SHOWERS OFFSHORE SO RAIN REMAINS LIKELY AT COASTAL SITES WITH EVEN A RUMBLE OF THUNDER POSSIBLE. ANOTHER SYSTEM WILL BRING MORE RAIN AND LIKELY MVFR CONDITIONS TONIGHT STARTING AT THE COAST AND MOVING INLAND DURING THE OVERNIGHT HOURS. A SLIGHT THUNDER THREAT WILL EXPAND INLAND OVERNIGHT AND LAST THROUGH MONDAY AFTERNOON. HOWEVER CONFIDENCE IS TOO LOW FOR INLAND AREAS TO INCLUDE IN THE TAF AT THIS POINT. KPDX AND APPROACHES...VFR CONDITIONS PREVAILING WITH POSSIBLE TEMPO MVFR CONDITIONS THROUGH ABOUT 01Z. CHANCE OF MVFR CONDITIONS INCREASES AGAIN LATE TONIGHT AND EARLY MONDAY MORNING WITH RETURN OF SHOWERS. && .MARINE...TODAY`S FRONT DID`T PACK QUITE AS MUCH PUNCH AS ORIGINALLY THOUGHT WITH WINDS GENERALLY REMAINING BELOW 20 KT. WITH FRONT ONSHORE AT THIS POINT...PEAK WINDS SHOULD HAVE ALREADY OCCURRED AND WITH RECENT ASCAT PASS SHOWING WINDS LESS THAN 20 KT...HAVE KILLED ALL SMALL CRAFT ADVISORIES FOR TODAY. WITH LESSER WINDS...SEAS ARE ONLY RUNNING 5 TO 6 FT AND SHOULD ONLY INCREASE SLIGHTLY TO MAYBE 7 FT OVERNIGHT. ANOTHER SYSTEM APPROACHES THE WATERS BEGINNING TONIGHT WITH WINDS INCREASING MAINLY OVER THE CENTRAL OREGON WATERS. ISSUED A SMALL CRAFT ADVISORY FOR WINDS BEGINNING 12Z MONDAY WHICH WILL RUN THROUGH 06Z TUESDAY. NOT AS CONFIDENT AT THIS POINT THAT SMALL CRAFT WINDS WILL OCCUR OVER THE NORTHER OREGON WATERS...SO HAVE LEFT THAT AREA OUT FOR NOW. SEAS WILL RISE SLOWLY MONDAY BUT CONFIDENCE IS LOW IN THEM REACHING 10 FT...SO HAVE NOT ISSUED ANYTHING FOR SEAS AT THIS TIME. MODELS HAVE COME INTO DECENT AGREEMENT ABOUT A LOW PRESSURE SYSTEM APPROACHING THE CENTRAL OREGON WATERS AND MOVING INLAND MONDAY NIGHT. HOWEVER IDEAS OF THE STRENGTH OF THE LOW STILL VARY SIGNIFICANTLY...SO IT`S HARD TO SAY EXACTLY HOW STRONG WINDS WILL BE. SMALL CRAFT WINDS SEEM LIKELY OVER THE CENTRAL OREGON WATERS BUT GALES CANNOT BE RULED OUT AT THIS POINT. SEAS LOOK LIKE THEY WILL BUILD TO AROUND 10 FT WITH THIS SYSTEM AND WILL BE PARTICULARLY CHOPPY IN AREAS WITH HIGHER WINDS. CONDITIONS SHOULD IMPROVE DURING THE DAY TUESDAY BEHIND THE LOW PASSAGE. MODELS SHOW ONE LAST WAVE BRUSHING THE NORTHERN OREGON WATERS WEDNESDAY WHICH COULD BRING SMALL CRAFT WINDS...BUT OTHERWISE THE REST OF THE FORECAST PERIOD APPEARS RATHER FAVORABLE AS HIGH PRESSURE BUILDS OVER THE AFTER MIDWEEK. BOWEN/26 && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 5 AM TO 11 PM PDT MONDAY FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 8 PM PDT THIS EVENING. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO 10 AM PDT MONDAY. && $$ INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/NWSPORTLAND WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
  [top] Area Forecast Discussion National Weather Service Spokane WA 242 PM PDT SUN MAR 22 2015 .SYNOPSIS... High pressure will bring a relatively quiet weather day on Sunday before another moist and breezy cold front arrives tonight. Showery weather will be in place through midweek, then a gradual warming and drying trend returns late in the week. && .DISCUSSION... Tonight through Monday...An unsettled and potentially wet period awaits the Inland NW care of a occluded front tonight and an cool and unstable trough for Monday. The occluded front was currently over western portions of Washington and Oregon...and was moving slowly northeastward. We`ve already begun to see mid-level moisture and warm air advection bring some clouds and sprinkles over extreme SE WA/NC Idaho as well as near the Cascades. This area will certainly increase in coverage overnight as the front begins to head east of the Cascades. The front will pass through the Cascades during the evening and by midnight should head into the eastern third of Washington and the Idaho Panhandle. Precipitation from the front should be widespread...however it won`t be heavy...and it may not even measure in the lee of the Cascades. There is an exception though over SE Washington and the southern Panhandle. Model guidance has been consistent in painting this area in moderate precipitation. This is likely in response to the shortwave trough currently buckling the occluded front over SW Oregon and NW California. The 18z NAM is showing this nicely and it enhances the lift and moisture content along the front near the Lewiston area by mid/late evening. This enhanced precipitation potential will likely continue until drier air moves in behind the front toward daybreak. QPF totals vary widely between model guidance suites, however we will follow the GEFS and SREF guidance and put QPF totals in the 0.25-0.50 inch range. Local amounts will likely be higher especially over the Clearwater Mountains as orographic enhancements will likely develop over southwest facing slopes. For Monday...drier air will initially work over the region...however its residence will be brief as another shortwave trough moves into from the southwest. This one will have less moisture and upper level forcing to work with however it will have the benefit of deeper instability. 500 mb temps plummet into the -28 to -30c range by afternoon as the weakening negative tilted trough moves in. This results in deepening instability with model soundings indicating the small potential for thunderstorms. It`s far from a slam dunk due to limited instability (less than we had yesterday) plus the cloud base temperatures are around -4 to -6c. This is still warm enough to have liquid in the cloud bases...but it may not be plentiful. Thus this could limit the crucial charge separation needed for lightning. Based on SREF instability progs and the GFS MUCAPEs...we will place the best chances of thunder north and east of the upper level trough axis. This is roughly east of a line from Tonasket to Ritzville. Snow levels will fall as well with the cooler air and its conceivable that any location could receive graupel showers. However as for accumulating snows...we expect that to occur generally between 3500-4000 ft and above. Amounts will not be heavy unless showers continually move over the same locations. fx Monday night through Wednesday...the region will be under the influence of an upper level trough and associated cold pool aloft during this forecast period. Instability showers will affect most of the forecast area with the greatest areal coverage during the afternoon and evening hours. Additional dynamic support will be provided by a an elongated vorticity maximum in the base of the broad trough that will slide over the Inland Northwest Tuesday and Tuesday night. Most favored areas will be the northern mountains and the rising terrain east of the basin. Convective parameters should be adequate to foster a few thunderstorms with the best chance for thunder being Monday evening over the northeast zones. By Wednesday, a ridge of high pressure will start building over the region. Models continue to indicate a decent amount of moisture riding along the ridge so any residual vorticity, aided by northwest upslope flow, will be able to wring out a few showers, mainly over the Idaho panhandle. Winds will be breezy to windy Monday night then lighten overnight. Temperatures will be a bit on the cool side Tuesday under the upper trough, then warm a few degrees for Wednesday as the ridge builds and cloud cover diminishes. /Kelch Wednesday night through Sunday: A ridge of high pressure builds in through the end of the work week, leading to an overall drying and warming trend. But first some shower chances linger. Wednesday night and Thursday the region will be in a northwest flow, with the jet axis migrating east-southeast across the northern Rockies. A boundary across north Idaho gradually shifts east too. Models also show a weak mid-level vorticity max dropping south across Washington into Oregon. Additionally PWATs linger around 0.50 to 0.75 inches. Individually none of these are particularly impressive. However together they will keep some shower threat alive. Chances will be best across the Cascades and southeast Washington through the central Panhandle Wednesday night, then mainly over the central Panhandle Thursday. Overall precipitation amounts, if anything accumulates, looks light. Otherwise the building ridge will lead to drier weather, with a few passing middle to high clouds. The ridge is dampened toward next weekend with a Pacific trough pushing east. However models have trended strong with the ridge and now indicate that trough stretches and splits. The southern split remains off the CA coast and the northern split moves across western Canada, mainly brushing our northern CWA through the weekend. This will return some slight shower threat to the Cascades and near the Canadian border; otherwise models indicate a drier forecast. Temperatures are projected to undergo a general warming trend that still looks to peak on Friday, with highs at this time projected to be around 10 to 15 degrees above average. /J. Cote` && .AVIATION... 18Z TAFS: VFR conditions expected at all TAF sites through 18Z Monday although a developing rain situation will potentially lower cloud heights. Through 00z this afternoon there could be a few sprinkles, especially over SE WA/NC ID and near the Cascades...but cigs will remain AOA 070. For tonight...a better chance of -ra will arrive over all forecast sites. Most of the precip will be light...however a little better forcing could result in heavier and more persistent precipitation for LWS and PUW between 02z-11z. If this really develops...there could be MVFR cigs...especially for PUW...but didn`t think the risk was large enough to place in forecast. Precip threat will end from W-E overnight and into early Monday morning. fx && .PRELIMINARY POINT TEMPS/POPS... Spokane 40 50 34 48 33 53 / 60 50 40 40 30 30 Coeur d`Alene 37 49 33 47 31 51 / 80 60 60 50 40 30 Pullman 40 50 36 48 35 53 / 90 70 70 50 40 30 Lewiston 43 53 38 53 37 56 / 90 70 60 40 30 20 Colville 38 55 33 53 31 54 / 90 60 60 50 20 30 Sandpoint 36 48 33 48 32 50 / 70 90 70 60 40 30 Kellogg 37 45 34 44 33 48 / 100 90 80 70 50 30 Moses Lake 38 58 35 56 34 60 / 30 20 10 20 10 20 Wenatchee 40 59 39 58 39 60 / 40 30 10 20 10 20 Omak 38 57 33 55 32 57 / 70 30 20 30 10 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion National Weather Service Spokane WA 242 PM PDT SUN MAR 22 2015 .SYNOPSIS... High pressure will bring a relatively quiet weather day on Sunday before another moist and breezy cold front arrives tonight. Showery weather will be in place through midweek, then a gradual warming and drying trend returns late in the week. && .DISCUSSION... Tonight through Monday...An unsettled and potentially wet period awaits the Inland NW care of a occluded front tonight and an cool and unstable trough for Monday. The occluded front was currently over western portions of Washington and Oregon...and was moving slowly northeastward. We`ve already begun to see mid-level moisture and warm air advection bring some clouds and sprinkles over extreme SE WA/NC Idaho as well as near the Cascades. This area will certainly increase in coverage overnight as the front begins to head east of the Cascades. The front will pass through the Cascades during the evening and by midnight should head into the eastern third of Washington and the Idaho Panhandle. Precipitation from the front should be widespread...however it won`t be heavy...and it may not even measure in the lee of the Cascades. There is an exception though over SE Washington and the southern Panhandle. Model guidance has been consistent in painting this area in moderate precipitation. This is likely in response to the shortwave trough currently buckling the occluded front over SW Oregon and NW California. The 18z NAM is showing this nicely and it enhances the lift and moisture content along the front near the Lewiston area by mid/late evening. This enhanced precipitation potential will likely continue until drier air moves in behind the front toward daybreak. QPF totals vary widely between model guidance suites, however we will follow the GEFS and SREF guidance and put QPF totals in the 0.25-0.50 inch range. Local amounts will likely be higher especially over the Clearwater Mountains as orographic enhancements will likely develop over southwest facing slopes. For Monday...drier air will initially work over the region...however its residence will be brief as another shortwave trough moves into from the southwest. This one will have less moisture and upper level forcing to work with however it will have the benefit of deeper instability. 500 mb temps plummet into the -28 to -30c range by afternoon as the weakening negative tilted trough moves in. This results in deepening instability with model soundings indicating the small potential for thunderstorms. It`s far from a slam dunk due to limited instability (less than we had yesterday) plus the cloud base temperatures are around -4 to -6c. This is still warm enough to have liquid in the cloud bases...but it may not be plentiful. Thus this could limit the crucial charge separation needed for lightning. Based on SREF instability progs and the GFS MUCAPEs...we will place the best chances of thunder north and east of the upper level trough axis. This is roughly east of a line from Tonasket to Ritzville. Snow levels will fall as well with the cooler air and its conceivable that any location could receive graupel showers. However as for accumulating snows...we expect that to occur generally between 3500-4000 ft and above. Amounts will not be heavy unless showers continually move over the same locations. fx Monday night through Wednesday...the region will be under the influence of an upper level trough and associated cold pool aloft during this forecast period. Instability showers will affect most of the forecast area with the greatest areal coverage during the afternoon and evening hours. Additional dynamic support will be provided by a an elongated vorticity maximum in the base of the broad trough that will slide over the Inland Northwest Tuesday and Tuesday night. Most favored areas will be the northern mountains and the rising terrain east of the basin. Convective parameters should be adequate to foster a few thunderstorms with the best chance for thunder being Monday evening over the northeast zones. By Wednesday, a ridge of high pressure will start building over the region. Models continue to indicate a decent amount of moisture riding along the ridge so any residual vorticity, aided by northwest upslope flow, will be able to wring out a few showers, mainly over the Idaho panhandle. Winds will be breezy to windy Monday night then lighten overnight. Temperatures will be a bit on the cool side Tuesday under the upper trough, then warm a few degrees for Wednesday as the ridge builds and cloud cover diminishes. /Kelch Wednesday night through Sunday: A ridge of high pressure builds in through the end of the work week, leading to an overall drying and warming trend. But first some shower chances linger. Wednesday night and Thursday the region will be in a northwest flow, with the jet axis migrating east-southeast across the northern Rockies. A boundary across north Idaho gradually shifts east too. Models also show a weak mid-level vorticity max dropping south across Washington into Oregon. Additionally PWATs linger around 0.50 to 0.75 inches. Individually none of these are particularly impressive. However together they will keep some shower threat alive. Chances will be best across the Cascades and southeast Washington through the central Panhandle Wednesday night, then mainly over the central Panhandle Thursday. Overall precipitation amounts, if anything accumulates, looks light. Otherwise the building ridge will lead to drier weather, with a few passing middle to high clouds. The ridge is dampened toward next weekend with a Pacific trough pushing east. However models have trended strong with the ridge and now indicate that trough stretches and splits. The southern split remains off the CA coast and the northern split moves across western Canada, mainly brushing our northern CWA through the weekend. This will return some slight shower threat to the Cascades and near the Canadian border; otherwise models indicate a drier forecast. Temperatures are projected to undergo a general warming trend that still looks to peak on Friday, with highs at this time projected to be around 10 to 15 degrees above average. /J. Cote` && .AVIATION... 18Z TAFS: VFR conditions expected at all TAF sites through 18Z Monday although a developing rain situation will potentially lower cloud heights. Through 00z this afternoon there could be a few sprinkles, especially over SE WA/NC ID and near the Cascades...but cigs will remain AOA 070. For tonight...a better chance of -ra will arrive over all forecast sites. Most of the precip will be light...however a little better forcing could result in heavier and more persistent precipitation for LWS and PUW between 02z-11z. If this really develops...there could be MVFR cigs...especially for PUW...but didn`t think the risk was large enough to place in forecast. Precip threat will end from W-E overnight and into early Monday morning. fx && .PRELIMINARY POINT TEMPS/POPS... Spokane 40 50 34 48 33 53 / 60 50 40 40 30 30 Coeur d`Alene 37 49 33 47 31 51 / 80 60 60 50 40 30 Pullman 40 50 36 48 35 53 / 90 70 70 50 40 30 Lewiston 43 53 38 53 37 56 / 90 70 60 40 30 20 Colville 38 55 33 53 31 54 / 90 60 60 50 20 30 Sandpoint 36 48 33 48 32 50 / 70 90 70 60 40 30 Kellogg 37 45 34 44 33 48 / 100 90 80 70 50 30 Moses Lake 38 58 35 56 34 60 / 30 20 10 20 10 20 Wenatchee 40 59 39 58 39 60 / 40 30 10 20 10 20 Omak 38 57 33 55 32 57 / 70 30 20 30 10 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion National Weather Service Spokane WA 242 PM PDT SUN MAR 22 2015 .SYNOPSIS... High pressure will bring a relatively quiet weather day on Sunday before another moist and breezy cold front arrives tonight. Showery weather will be in place through midweek, then a gradual warming and drying trend returns late in the week. && .DISCUSSION... Tonight through Monday...An unsettled and potentially wet period awaits the Inland NW care of a occluded front tonight and an cool and unstable trough for Monday. The occluded front was currently over western portions of Washington and Oregon...and was moving slowly northeastward. We`ve already begun to see mid-level moisture and warm air advection bring some clouds and sprinkles over extreme SE WA/NC Idaho as well as near the Cascades. This area will certainly increase in coverage overnight as the front begins to head east of the Cascades. The front will pass through the Cascades during the evening and by midnight should head into the eastern third of Washington and the Idaho Panhandle. Precipitation from the front should be widespread...however it won`t be heavy...and it may not even measure in the lee of the Cascades. There is an exception though over SE Washington and the southern Panhandle. Model guidance has been consistent in painting this area in moderate precipitation. This is likely in response to the shortwave trough currently buckling the occluded front over SW Oregon and NW California. The 18z NAM is showing this nicely and it enhances the lift and moisture content along the front near the Lewiston area by mid/late evening. This enhanced precipitation potential will likely continue until drier air moves in behind the front toward daybreak. QPF totals vary widely between model guidance suites, however we will follow the GEFS and SREF guidance and put QPF totals in the 0.25-0.50 inch range. Local amounts will likely be higher especially over the Clearwater Mountains as orographic enhancements will likely develop over southwest facing slopes. For Monday...drier air will initially work over the region...however its residence will be brief as another shortwave trough moves into from the southwest. This one will have less moisture and upper level forcing to work with however it will have the benefit of deeper instability. 500 mb temps plummet into the -28 to -30c range by afternoon as the weakening negative tilted trough moves in. This results in deepening instability with model soundings indicating the small potential for thunderstorms. It`s far from a slam dunk due to limited instability (less than we had yesterday) plus the cloud base temperatures are around -4 to -6c. This is still warm enough to have liquid in the cloud bases...but it may not be plentiful. Thus this could limit the crucial charge separation needed for lightning. Based on SREF instability progs and the GFS MUCAPEs...we will place the best chances of thunder north and east of the upper level trough axis. This is roughly east of a line from Tonasket to Ritzville. Snow levels will fall as well with the cooler air and its conceivable that any location could receive graupel showers. However as for accumulating snows...we expect that to occur generally between 3500-4000 ft and above. Amounts will not be heavy unless showers continually move over the same locations. fx Monday night through Wednesday...the region will be under the influence of an upper level trough and associated cold pool aloft during this forecast period. Instability showers will affect most of the forecast area with the greatest areal coverage during the afternoon and evening hours. Additional dynamic support will be provided by a an elongated vorticity maximum in the base of the broad trough that will slide over the Inland Northwest Tuesday and Tuesday night. Most favored areas will be the northern mountains and the rising terrain east of the basin. Convective parameters should be adequate to foster a few thunderstorms with the best chance for thunder being Monday evening over the northeast zones. By Wednesday, a ridge of high pressure will start building over the region. Models continue to indicate a decent amount of moisture riding along the ridge so any residual vorticity, aided by northwest upslope flow, will be able to wring out a few showers, mainly over the Idaho panhandle. Winds will be breezy to windy Monday night then lighten overnight. Temperatures will be a bit on the cool side Tuesday under the upper trough, then warm a few degrees for Wednesday as the ridge builds and cloud cover diminishes. /Kelch Wednesday night through Sunday: A ridge of high pressure builds in through the end of the work week, leading to an overall drying and warming trend. But first some shower chances linger. Wednesday night and Thursday the region will be in a northwest flow, with the jet axis migrating east-southeast across the northern Rockies. A boundary across north Idaho gradually shifts east too. Models also show a weak mid-level vorticity max dropping south across Washington into Oregon. Additionally PWATs linger around 0.50 to 0.75 inches. Individually none of these are particularly impressive. However together they will keep some shower threat alive. Chances will be best across the Cascades and southeast Washington through the central Panhandle Wednesday night, then mainly over the central Panhandle Thursday. Overall precipitation amounts, if anything accumulates, looks light. Otherwise the building ridge will lead to drier weather, with a few passing middle to high clouds. The ridge is dampened toward next weekend with a Pacific trough pushing east. However models have trended strong with the ridge and now indicate that trough stretches and splits. The southern split remains off the CA coast and the northern split moves across western Canada, mainly brushing our northern CWA through the weekend. This will return some slight shower threat to the Cascades and near the Canadian border; otherwise models indicate a drier forecast. Temperatures are projected to undergo a general warming trend that still looks to peak on Friday, with highs at this time projected to be around 10 to 15 degrees above average. /J. Cote` && .AVIATION... 18Z TAFS: VFR conditions expected at all TAF sites through 18Z Monday although a developing rain situation will potentially lower cloud heights. Through 00z this afternoon there could be a few sprinkles, especially over SE WA/NC ID and near the Cascades...but cigs will remain AOA 070. For tonight...a better chance of -ra will arrive over all forecast sites. Most of the precip will be light...however a little better forcing could result in heavier and more persistent precipitation for LWS and PUW between 02z-11z. If this really develops...there could be MVFR cigs...especially for PUW...but didn`t think the risk was large enough to place in forecast. Precip threat will end from W-E overnight and into early Monday morning. fx && .PRELIMINARY POINT TEMPS/POPS... Spokane 40 50 34 48 33 53 / 60 50 40 40 30 30 Coeur d`Alene 37 49 33 47 31 51 / 80 60 60 50 40 30 Pullman 40 50 36 48 35 53 / 90 70 70 50 40 30 Lewiston 43 53 38 53 37 56 / 90 70 60 40 30 20 Colville 38 55 33 53 31 54 / 90 60 60 50 20 30 Sandpoint 36 48 33 48 32 50 / 70 90 70 60 40 30 Kellogg 37 45 34 44 33 48 / 100 90 80 70 50 30 Moses Lake 38 58 35 56 34 60 / 30 20 10 20 10 20 Wenatchee 40 59 39 58 39 60 / 40 30 10 20 10 20 Omak 38 57 33 55 32 57 / 70 30 20 30 10 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion National Weather Service Spokane WA 242 PM PDT SUN MAR 22 2015 .SYNOPSIS... High pressure will bring a relatively quiet weather day on Sunday before another moist and breezy cold front arrives tonight. Showery weather will be in place through midweek, then a gradual warming and drying trend returns late in the week. && .DISCUSSION... Tonight through Monday...An unsettled and potentially wet period awaits the Inland NW care of a occluded front tonight and an cool and unstable trough for Monday. The occluded front was currently over western portions of Washington and Oregon...and was moving slowly northeastward. We`ve already begun to see mid-level moisture and warm air advection bring some clouds and sprinkles over extreme SE WA/NC Idaho as well as near the Cascades. This area will certainly increase in coverage overnight as the front begins to head east of the Cascades. The front will pass through the Cascades during the evening and by midnight should head into the eastern third of Washington and the Idaho Panhandle. Precipitation from the front should be widespread...however it won`t be heavy...and it may not even measure in the lee of the Cascades. There is an exception though over SE Washington and the southern Panhandle. Model guidance has been consistent in painting this area in moderate precipitation. This is likely in response to the shortwave trough currently buckling the occluded front over SW Oregon and NW California. The 18z NAM is showing this nicely and it enhances the lift and moisture content along the front near the Lewiston area by mid/late evening. This enhanced precipitation potential will likely continue until drier air moves in behind the front toward daybreak. QPF totals vary widely between model guidance suites, however we will follow the GEFS and SREF guidance and put QPF totals in the 0.25-0.50 inch range. Local amounts will likely be higher especially over the Clearwater Mountains as orographic enhancements will likely develop over southwest facing slopes. For Monday...drier air will initially work over the region...however its residence will be brief as another shortwave trough moves into from the southwest. This one will have less moisture and upper level forcing to work with however it will have the benefit of deeper instability. 500 mb temps plummet into the -28 to -30c range by afternoon as the weakening negative tilted trough moves in. This results in deepening instability with model soundings indicating the small potential for thunderstorms. It`s far from a slam dunk due to limited instability (less than we had yesterday) plus the cloud base temperatures are around -4 to -6c. This is still warm enough to have liquid in the cloud bases...but it may not be plentiful. Thus this could limit the crucial charge separation needed for lightning. Based on SREF instability progs and the GFS MUCAPEs...we will place the best chances of thunder north and east of the upper level trough axis. This is roughly east of a line from Tonasket to Ritzville. Snow levels will fall as well with the cooler air and its conceivable that any location could receive graupel showers. However as for accumulating snows...we expect that to occur generally between 3500-4000 ft and above. Amounts will not be heavy unless showers continually move over the same locations. fx Monday night through Wednesday...the region will be under the influence of an upper level trough and associated cold pool aloft during this forecast period. Instability showers will affect most of the forecast area with the greatest areal coverage during the afternoon and evening hours. Additional dynamic support will be provided by a an elongated vorticity maximum in the base of the broad trough that will slide over the Inland Northwest Tuesday and Tuesday night. Most favored areas will be the northern mountains and the rising terrain east of the basin. Convective parameters should be adequate to foster a few thunderstorms with the best chance for thunder being Monday evening over the northeast zones. By Wednesday, a ridge of high pressure will start building over the region. Models continue to indicate a decent amount of moisture riding along the ridge so any residual vorticity, aided by northwest upslope flow, will be able to wring out a few showers, mainly over the Idaho panhandle. Winds will be breezy to windy Monday night then lighten overnight. Temperatures will be a bit on the cool side Tuesday under the upper trough, then warm a few degrees for Wednesday as the ridge builds and cloud cover diminishes. /Kelch Wednesday night through Sunday: A ridge of high pressure builds in through the end of the work week, leading to an overall drying and warming trend. But first some shower chances linger. Wednesday night and Thursday the region will be in a northwest flow, with the jet axis migrating east-southeast across the northern Rockies. A boundary across north Idaho gradually shifts east too. Models also show a weak mid-level vorticity max dropping south across Washington into Oregon. Additionally PWATs linger around 0.50 to 0.75 inches. Individually none of these are particularly impressive. However together they will keep some shower threat alive. Chances will be best across the Cascades and southeast Washington through the central Panhandle Wednesday night, then mainly over the central Panhandle Thursday. Overall precipitation amounts, if anything accumulates, looks light. Otherwise the building ridge will lead to drier weather, with a few passing middle to high clouds. The ridge is dampened toward next weekend with a Pacific trough pushing east. However models have trended strong with the ridge and now indicate that trough stretches and splits. The southern split remains off the CA coast and the northern split moves across western Canada, mainly brushing our northern CWA through the weekend. This will return some slight shower threat to the Cascades and near the Canadian border; otherwise models indicate a drier forecast. Temperatures are projected to undergo a general warming trend that still looks to peak on Friday, with highs at this time projected to be around 10 to 15 degrees above average. /J. Cote` && .AVIATION... 18Z TAFS: VFR conditions expected at all TAF sites through 18Z Monday although a developing rain situation will potentially lower cloud heights. Through 00z this afternoon there could be a few sprinkles, especially over SE WA/NC ID and near the Cascades...but cigs will remain AOA 070. For tonight...a better chance of -ra will arrive over all forecast sites. Most of the precip will be light...however a little better forcing could result in heavier and more persistent precipitation for LWS and PUW between 02z-11z. If this really develops...there could be MVFR cigs...especially for PUW...but didn`t think the risk was large enough to place in forecast. Precip threat will end from W-E overnight and into early Monday morning. fx && .PRELIMINARY POINT TEMPS/POPS... Spokane 40 50 34 48 33 53 / 60 50 40 40 30 30 Coeur d`Alene 37 49 33 47 31 51 / 80 60 60 50 40 30 Pullman 40 50 36 48 35 53 / 90 70 70 50 40 30 Lewiston 43 53 38 53 37 56 / 90 70 60 40 30 20 Colville 38 55 33 53 31 54 / 90 60 60 50 20 30 Sandpoint 36 48 33 48 32 50 / 70 90 70 60 40 30 Kellogg 37 45 34 44 33 48 / 100 90 80 70 50 30 Moses Lake 38 58 35 56 34 60 / 30 20 10 20 10 20 Wenatchee 40 59 39 58 39 60 / 40 30 10 20 10 20 Omak 38 57 33 55 32 57 / 70 30 20 30 10 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion National Weather Service Spokane WA 1203 PM PDT SUN MAR 22 2015 .SYNOPSIS... High pressure will bring a relatively quiet weather day on Sunday before another moist and breezy cold front arrives tonight. Showery weather will be in place through midweek then a gradual warming and drying trend returns late in the week. && .DISCUSSION... Rest of today...Satellite this morning was showing considerable cloudiness moving into the region from the southwest. Much of this cloudiness was associated with a pool of moisture and mid-level warm air advection. Models having a tough time figuring out whether this will result in precipitation or not...however the radar doesn`t lie and its showing a northeast- southwest swath of precipitation stretching from the Waterville Plateau to Hood River. Thus far precipitation reports have been few and far between, however in the past hour Ephrata did pick up some rain and the radar echoes continue to maintain their strength as they move to the northeast. There were also some lighter radar echoes around Lewiston and the Camas Prairie heading to the east- northeast. These latter echoes are less of a concern through early afternoon...however still would not rule out some light sprinkles there. Better chances will arrive by late afternoon at the earliest, but more likely during the evening. For the activity over the Waterville Plateau...the only model which is showing any precipitation is the HRRR...and based or radar trends...we will follow its lead. This solution shows this activity continuing to feed to the NE through the afternoon...with light precipitation becoming possible across most locations of NC and NE Washington. Earlier the HRRR was also showing the light precipitation spreading into N Idaho, but lately it has backed off on that idea. Due to the variability...we will play it safe and throw light showers or sprinkles across that area as well. The other forecast change for today will revolve around temperatures. Clouds are appreciably more opaque and extensive than expected and this is having an impact on daytime heating. Consequently we will lower afternoon high temperatures, especially for locations over the Basin, Wenatchee area, and Okanogan Valley. fx && .AVIATION... 18Z TAFS: VFR conditions expected at all TAF sites through 18Z Monday although a developing rain situation will potentially lower cloud heights. Through 00z this afternoon there could be a few sprinkles, especially over SE WA/NC ID and near the Cascades...but cigs will remain AOA 070. For tonight...a better chance of -ra will arrive over all forecast sites. Most of the precip will be light...however a little better forcing could result in heavier and more persistent precipitation for LWS and PUW between 02z-11z. If this really develops...there could be MVFR cigs...especially for PUW...but didn`t think the risk was large enough to place in forecast. Precip threat will end from W-E overnight and into early Monday morning. fx && .PRELIMINARY POINT TEMPS/POPS... Spokane 57 41 52 34 49 35 / 10 100 60 40 40 30 Coeur d`Alene 58 40 52 33 48 32 / 10 100 70 60 50 40 Pullman 58 40 50 36 49 36 / 20 100 80 70 50 40 Lewiston 60 44 54 37 54 38 / 20 90 70 60 40 30 Colville 56 42 56 33 51 32 / 10 100 80 60 50 20 Sandpoint 57 37 50 33 47 32 / 10 100 100 70 60 40 Kellogg 56 37 47 34 44 33 / 20 100 90 80 70 50 Moses Lake 59 40 59 34 58 36 / 20 40 20 10 20 10 Wenatchee 56 36 59 39 58 40 / 20 50 20 10 20 10 Omak 57 39 59 33 56 33 / 10 50 40 20 30 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
546 PM CDT SUN MAR 22 2015 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 244 PM CDT SUN MAR 22 2015 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LIGHT TO MODERATE SNOW OCCURRING OVER SOUTHEAST MINNESOTA...SOUTHWEST WISCONSIN...AND NORTHEAST IOWA EARLY THIS AFTERNOON ALONG THE SOUTHWEST FLANK OF A POLAR AIRMASS. ANOTHER AREA OF SNOW EXISTS OVER THE EASTERN DAKOTAS AHEAD OF A COMPACT SHORTWAVE TROUGH. DRY AIR EMANATING FROM A CANADIAN HIGH CENTERED OVER THE GREAT LAKES HAS PREVENTED THE SNOW FROM REACHING THE GROUND OVER CENTRAL WISCONSIN DESPITE SOME RETURNS ON RADAR EARLIER. AS THE SHORTWAVE OVER THE DAKOTAS MOVES EAST...SNOW AND ACCUMULATION CHANCES ARE THE MAIN FORECAST CONCERNS. TONIGHT...800-700MB THERMAL GRADIENT WILL CONTINUE TO BE ACTIVE EARLY THIS EVENING OVER SOUTHWEST WISCONSIN. BUT THE MAIN PUSH OF SNOW WILL BE EXITING MINNESOTA BY MID TO LATE EVENING AHEAD OF A SHORTWAVE TROUGH...IN CONJUNCTION WITH MID-LEVEL FGEN ON THE NOSE OF A 25KT LLJ AND A COUPLED JET STRUCTURE. CENTRAL WISCONSIN WILL BE ON THE NORTHERN FRINGE OF THE AREA OF SNOW WHERE LOW LEVEL EASTERLY WINDS WILL BE FEEDING IN DRY AIR. SOUNDINGS BECOME SATURATED ABOVE 750MB BY 06Z ACCORDING TO THE NAM...WHILE THE MESOMODELS AND SREF ARE SLIGHTLY MORE AGGRESSIVE BRINGING IN PRECIP BY THIS TIME INTO WOOD COUNTY. AS A RESULT...WILL INCREASE PRECIP CHANCES IN THAT CENTRAL WISCONSIN AREA IN THE 06-09Z PERIOD. ACCUMULATIONS COULD REACH UP TO AN INCH IN WOOD COUNTY BUT ONLY A TENTH OR TWO FROM WAUSAU TO OSHKOSH. THE REST OF THE AREA SHOULD SEE INCREASING CLOUDS. LOWS RANGING FROM THE UPPER TEENS NORTHEAST TO THE MIDDLE 20S SOUTH. MONDAY...ANY PRECIP WILL HAVE EXITED CENTRAL WISCONSIN BY THE START OF THE MORNING BUT CLOUDS WILL TAKE MUCH LONGER TO THIN AS CENTRAL WISCONSIN WILL BE ON THE NORTHEAST EDGE OF THE BAROCLINIC ZONE. NORTHEAST WISCONSIN WILL HAVE A MUCH GREATER CHANCE OF CLEARING DURING THE AFTERNOON. THE COMBINATION OF CLOUDS AND AN EAST WIND WILL KEEP MAX TEMPS COOL. HIGHS WILL BE RANGING THROUGH THE 30S. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 244 PM CDT SUN MAR 22 2015 MAIN CONCERN FOR THIS PACKAGE WILL BE THE SYSTEM TUESDAY NIGHT AND WEDNESDAY...THEN BELOW NORMAL TEMPERATURES FOR THE END OF THE WORK WEEK INTO NEXT WEEKEND. 12Z MODELS CONTINUE TO SHOW SIGNIFICANT SYSTEM MOVING ACROSS THE REGION TUESDAY NIGHT INTO WEDNESDAY. MANY ISSUES TO CONTEND WITH PRECIPITATION TYPE DUE TO DRY AND COLD EASTERLY FLOW WITH LOW DEW POINTS TUESDAY AFTERNOON...THEN WARM LAYER ALOFT TUESDAY NIGHT INTO WEDNESDAY. ONE THING IS FOR SURE...PLENTY OF DRY AIR IN THE LOW LEVELS TO OVERCOME AS NUMERICAL GUIDANCE INDICATING DEW POINTS IN THE TEENS TO LOWER 20S. ALOFT...MODELS DIFFER ON HOW FAR NORTH WARM LAYER WILL GET ON INCREASING SOUTHEAST TO SOUTH WINDS. ALSO... ANOTHER FACTOR THAT MAY IMPACT PRECIPITATION TYPES WILL BE THE STEEP MID LEVEL LAPSE RATES (700-500MB) AROUND 6.5 C/KM. EVEN THE WARM LOCATIONS ACROSS EAST CENTRAL WISCONSIN COULD SEE A MIX OR START AS SNOW UNTIL WARMER AND MORE MOIST AIR ARRIVES. THESE ISSUES WILL HAVE AN IMPACT ON SNOW TOTALS...BUT FEEL CONFIDENT THAT AN ACCUMULATING SNOW WILL OCCUR ACROSS THE NORTH. PRECIPITATION WILL LINGER INTO WEDNESDAY AS SYSTEM DEPARTS THE REGION. AN UPPER TROUGH MOVING ACROSS THE REGION WILL BRING A CHANCE OF RAIN OR SNOW WEDNESDAY NIGHT AND THURSDAY. MAINLY DRY CONDITIONS ARE EXPECTED INTO SATURDAY THE NEXT CHANCE OF RAIN AND SNOW IS EXPECTED SATURDAY NIGHT AND SUNDAY. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 511 PM CDT SUN MAR 22 2015 AN UPPER DISTURBANCE WILL TRACK SOUTHWEST OF THE AREA TONIGHT. A NARROW NORTHWEST TO SOUTHEAST BAND OF SNOW WILL EXTEND FROM CENTRAL MINNESOTA TO FAR SOUTHWEST WISCONSIN TO NORTHERN ILLINOIS. SOME MVFR CIGS WITH LIGHT SNOW MAY WORK INTO PARTS OF CENTRAL WISCONSIN OR SOUTH OF LINE FROM MFI TO Y50 FOR AT TIME TONIGHT...OTHERWISE VFR CONDITIONS EXPECTED TONIGHT INTO MONDAY. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......ECKBERG AVIATION.......TDH
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND MONDAY ISSUED AT 244 PM CDT SUN MAR 22 2015 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LIGHT TO MODERATE SNOW OCCURRING OVER SOUTHEAST MINNESOTA...SOUTHWEST WISCONSIN...AND NORTHEAST IOWA EARLY THIS AFTERNOON ALONG THE SOUTHWEST FLANK OF A POLAR AIRMASS. ANOTHER AREA OF SNOW EXISTS OVER THE EASTERN DAKOTAS AHEAD OF A COMPACT SHORTWAVE TROUGH. DRY AIR EMANATING FROM A CANADIAN HIGH CENTERED OVER THE GREAT LAKES HAS PREVENTED THE SNOW FROM REACHING THE GROUND OVER CENTRAL WISCONSIN DESPITE SOME RETURNS ON RADAR EARLIER. AS THE SHORTWAVE OVER THE DAKOTAS MOVES EAST...SNOW AND ACCUMULATION CHANCES ARE THE MAIN FORECAST CONCERNS. TONIGHT...800-700MB THERMAL GRADIENT WILL CONTINUE TO BE ACTIVE EARLY THIS EVENING OVER SOUTHWEST WISCONSIN. BUT THE MAIN PUSH OF SNOW WILL BE EXITING MINNESOTA BY MID TO LATE EVENING AHEAD OF A SHORTWAVE TROUGH...IN CONJUNCTION WITH MID-LEVEL FGEN ON THE NOSE OF A 25KT LLJ AND A COUPLED JET STRUCTURE. CENTRAL WISCONSIN WILL BE ON THE NORTHERN FRINGE OF THE AREA OF SNOW WHERE LOW LEVEL EASTERLY WINDS WILL BE FEEDING IN DRY AIR. SOUNDINGS BECOME SATURATED ABOVE 750MB BY 06Z ACCORDING TO THE NAM...WHILE THE MESOMODELS AND SREF ARE SLIGHTLY MORE AGGRESSIVE BRINGING IN PRECIP BY THIS TIME INTO WOOD COUNTY. AS A RESULT...WILL INCREASE PRECIP CHANCES IN THAT CENTRAL WISCONSIN AREA IN THE 06-09Z PERIOD. ACCUMULATIONS COULD REACH UP TO AN INCH IN WOOD COUNTY BUT ONLY A TENTH OR TWO FROM WAUSAU TO OSHKOSH. THE REST OF THE AREA SHOULD SEE INCREASING CLOUDS. LOWS RANGING FROM THE UPPER TEENS NORTHEAST TO THE MIDDLE 20S SOUTH. MONDAY...ANY PRECIP WILL HAVE EXITED CENTRAL WISCONSIN BY THE START OF THE MORNING BUT CLOUDS WILL TAKE MUCH LONGER TO THIN AS CENTRAL WISCONSIN WILL BE ON THE NORTHEAST EDGE OF THE BAROCLINIC ZONE. NORTHEAST WISCONSIN WILL HAVE A MUCH GREATER CHANCE OF CLEARING DURING THE AFTERNOON. THE COMBINATION OF CLOUDS AND AN EAST WIND WILL KEEP MAX TEMPS COOL. HIGHS WILL BE RANGING THROUGH THE 30S. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 244 PM CDT SUN MAR 22 2015 MAIN CONCERN FOR THIS PACKAGE WILL BE THE SYSTEM TUESDAY NIGHT AND WEDNESDAY...THEN BELOW NORMAL TEMPERATURES FOR THE END OF THE WORK WEEK INTO NEXT WEEKEND. 12Z MODELS CONTINUE TO SHOW SIGNIFICANT SYSTEM MOVING ACROSS THE REGION TUESDAY NIGHT INTO WEDNESDAY. MANY ISSUES TO CONTEND WITH PRECIPITATION TYPE DUE TO DRY AND COLD EASTERLY FLOW WITH LOW DEW POINTS TUESDAY AFTERNOON...THEN WARM LAYER ALOFT TUESDAY NIGHT INTO WEDNESDAY. ONE THING IS FOR SURE...PLENTY OF DRY AIR IN THE LOW LEVELS TO OVERCOME AS NUMERICAL GUIDANCE INDICATING DEW POINTS IN THE TEENS TO LOWER 20S. ALOFT...MODELS DIFFER ON HOW FAR NORTH WARM LAYER WILL GET ON INCREASING SOUTHEAST TO SOUTH WINDS. ALSO... ANOTHER FACTOR THAT MAY IMPACT PRECIPITATION TYPES WILL BE THE STEEP MID LEVEL LAPSE RATES (700-500MB) AROUND 6.5 C/KM. EVEN THE WARM LOCATIONS ACROSS EAST CENTRAL WISCONSIN COULD SEE A MIX OR START AS SNOW UNTIL WARMER AND MORE MOIST AIR ARRIVES. THESE ISSUES WILL HAVE AN IMPACT ON SNOW TOTALS...BUT FEEL CONFIDENT THAT AN ACCUMULATING SNOW WILL OCCUR ACROSS THE NORTH. PRECIPITATION WILL LINGER INTO WEDNESDAY AS SYSTEM DEPARTS THE REGION. AN UPPER TROUGH MOVING ACROSS THE REGION WILL BRING A CHANCE OF RAIN OR SNOW WEDNESDAY NIGHT AND THURSDAY. MAINLY DRY CONDITIONS ARE EXPECTED INTO SATURDAY THE NEXT CHANCE OF RAIN AND SNOW IS EXPECTED SATURDAY NIGHT AND SUNDAY. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1147 AM CDT SUN MAR 22 2015 BROKEN MID AND HIGH CLOUDS WILL WORK ACROSS THE FORECAST AREA THROUGH THE TAF PERIOD. CLOUDS WILL LOWER LATE THIS EVENING INTO THE OVERNIGHT HOURS AS A UPPER LEVEL DISTURBANCE PASSES ACROSS THE REGION. LIGHT SNOW WILL BE POSSIBLE OVER CENTRAL WISCONSIN AND THE SOUTHERN FOX VALLEY FROM THIS SYSTEM WITH UP TO AN INCH OF ACCUMULATION POSSIBLE NEAR WISCONSIN RAPIDS AND MARSHFIELD...BUT LESS THAN A HALF INCH AT WAUSAU AND STEVENS POINT. ANY SNOW WILL BE EXITING BY AROUND SUNRISE. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......ECKBERG AVIATION.......MPC