Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/03/14


AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1008 AM MST SAT MAR 1 2014 .SYNOPSIS... A WELL DEFINED PACIFIC STORM SYSTEM WILL SLOWLY MOVE THROUGH THE AREA TODAY...BRINGING SHOWERS AND ISOLATED THUNDERSTORMS TO THE PHOENIX AREA. CONDITIONS WILL DRY OUT FROM WEST TO EAST THIS EVENING WITH NEARLY EVERYONE DRYING OUT COMPLETELY BY SUNDAY AFTERNOON. DRY WEATHER IS EXPECTED NEXT WEEK ALONG WITH A RETURN TO ABOVE NORMAL TEMPERATURES. && .DISCUSSION... NOT MUCH CHANGE IN FORECAST THINKING AT THIS POINT...AS WE REMAIN UNDER THE WETTER INFLUENCE OF A STRONG UPPER LEVEL LOW THAT CONTINUES TO SPIN OFF THE CALIFORNIA COAST THIS MORNING. MANY LOCATIONS ACROSS SOUTHEAST CALIFORNIA...SOUTHWEST AND SOUTH-CENTRAL ARIZONA HAVE SEEN PERIODS OF RAINFALL OVER THE PAST 24 HOURS OR SO...AN AVERAGE OF 0.25IN TO 0.75IN FOR MANY LOWER DESERT ELEVATION SITES ACROSS OUR CWA...AND JUST OVER 1.0IN FOR OUR HIGHER MOUNTAIN SITES IN JTNP IN CALIFORNIA...AND ALSO GLOBE IN ARIZONA. THE PATTERN WILL CONTINUE TODAY...BUT MORE SO OVER OUR ARIZONA ZONES/LOCATIONS EAST OF THE LOWER COLORADO RIVER VALLEY...AS A PRECIPITABLE WATER AXIS IN EXCESS OF 1.0IN REMAINS POSITIONED OVER SOUTH-CENTRAL ARIZONA ALONG WITH 850-700MB WINDS AROUND 60-65KTS. MANY LOCATION ACROSS MARICOPA COUNTY...INCLUDING THE GREAT PHOENIX METROPOLITAN HAVE EXCELLENT CHANCES TO PICK UP AN ADDITIONAL QUARTER TO ONE HALF INCH MORE RAIN BEFORE THE DAY IS THROUGH....AND HIGHER TERRAIN AREAS TO THE EAST NEAR GLOBE AND ROOSEVELT...MAYBE UP TO ONE MORE INCH. REGIONAL RADAR MOSAIC CONTINUES TO SHOW STORMS FORMING OVER PORTIONS OF MARICOPA COUNTY AND SOUTHERN GILA COUNTY...SOME OF THE MORE INTENSE CELLS HAVE PRODUCED CLOSE TO 0.30IN IN A 15 MINUTE PERIOD BEFORE QUICKLY MOVING OFF TO THE NORTHEAST. THIS RATE IS NOT A BIG CONCERN UNLESS THE STORMS SLOW DOWN AND/OR BEGIN TRAINING OVER THE SAME AREA...SO WE WILL BE MONITORING FOR ANY LOCALIZED PONDING OR FLOODING OF ROADWAYS. THE HI-RES WRFS/NAM 4KM NEST CONTINUE TO HAVE THE BEST HANDLE ON HOW CONVECTION AND SHOWERS WILL EVOLVE IN THE SHORT TERM. ANTICIPATING THAT ONCE THE 500MB COLD CORE MOVES OVERHEAD BETWEEN 18Z AND 00Z... STORMS WILL BLOSSOM AGAIN ACROSS THE LOWER DESERTS AS MID LEVEL LAPSE RATES STEEPEN DRAMATICALLY. SOUTHEAST CALIFORNIA WILL LOSE THEIR DEEPEST MOISTURE LATER THIS MORNING...SO POPS ACROSS THAT AREA WILL BE LESS THAN THAT OVER THE GREATER PHOENIX AREA AND POINT EAST. THE TROUGH AXIS PASSES OVERHEAD AROUND 06Z TONIGHT AND CONDITIONS SHOULD BEGIN DRYING OUT AS EARLY AS SUNDAY MORNING. FOR THE VAST MAJORITY OF THE LOWER DESERTS...SUNDAY MAY END UP TURNING OUT TO BE A PRETTY NICE DAY WITH GRADUALLY CLEARING SKIES BY EARLY AFTERNOON. SOUTHERN GILA COUNTY WILL LIKELY SEE SHOWERS HANG ON THE LONGEST...BUT EVEN THEY MAY END UP CLEARING OUT SOONER THAN LATER. POPS WERE ADJUSTED SLIGHTLY DOWNWARD ACROSS THE BOARD SUNDAY MORNING THROUGH SUNDAY AFTERNOON. AFTER THAT...ZONAL FLOW WILL ESTABLISH ITSELF ON MONDAY FOLLOWED BY WEAK MID-WEEK RIDGING. LOOK FOR TEMPERATURES TO SLOWLY RESPOND BACK TO NORMAL BY MID WEEK AND ABOVE NORMAL BY THE END OF THE WEEK. THERE IS SOME SUGGESTION OF A TROUGH MOVING THROUGH THE FOUR CORNERS LATE IN THE WEEK /FRIDAY OR SATURDAY/ BUT PRECIP POTENTIAL LOOKS MINIMAL GIVEN THE SOURCE REGION OF THE TROUGH. COULD BRING SOME BREEZINESS AND SLIGHTLY COOLER TEMPS BUT THAT LOOKS TO BE ABOUT IT. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... LOWER LEVEL MOISTURE AND SCATTERED SHOWERS ASSOCIATED WITH A PASSING FRONTAL ZONE HAS CAUSED CIGS TO LOWER TO 4-6 KFT MSL IN THE VICINITY OF THE SHOWERS...BRIEFLY LOWER IN SOME SPOTS. HOWEVER...CLOUD BASES ARE HIGHLY VARIABLE BETWEEN SHOWERS...ABOVE 6 KFT MSL OVER SOUTHEAST METRO PHOENIX AS OF 13Z. FLUCTUATING CIGS WITH PASSING SHOWERS IS ANTICIPATED TO CONTINUE THROUGH 16Z BEFORE SHOWERS TEMPORARILY DECREASE. ANTICIPATE RENEWED DEVELOPMENT THIS AFTERNOON AS THE UPPER LOW GETS CLOSER. ISOLATED T-STORMS POSSIBLE BUT CONFIDENCE TOO LOW AT ANY GIVEN SPOT TO REFLECT IN THE TAFS. ANTICIPATE SCATTERED SHOWERS TO CONTINUE INTO THE EVENING BEFORE TRAILING OFF OVERNIGHT. SOUTHWEST WINDS WILL PREVAIL WITH OCCASIONAL GUSTS TO 20 KTS. STRONGER SHOWERS COULD PRODUCE 25+ KTS. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... SHOWERS ARE STRUGGLING TO MAKE IT OVER THE COASTAL MOUNTAINS TO THE WEST. HRRR MODEL INDICATES ISOLATED SHOWER DEVELOPMENT AFTER 14Z INCREASING TO SCATTERED COVERAGE AFTER 20Z AND THIS IS REFLECTED IN THE TAFS. ISOLATED T-STORMS POSSIBLE BUT CONFIDENCE TOO LOW AT ANY GIVEN SPOT TO REFLECT IN THE TAFS. ANTICIPATE SCATTERED SHOWERS TO CONTINUE INTO THE EVENING BEFORE TRAILING OFF OVERNIGHT. LIGHT AND VARIABLE SURFACE WINDS WILL BECOME SOUTHWEST BY MIDDAY WITH OCCASIONAL GUSTS TO 20 KTS. STRONGER SHOWERS COULD PRODUCE 25+ KTS. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... MONDAY THROUGH FRIDAY... HIGH PRESSURE BUILDS BACK INTO THE REGION MONDAY THROUGH WEDNESDAY FOR A WARMING TREND ALONG WITH LESS WIND. HUMIDITIES WILL DECREASE THOUGH OVERNIGHT RECOVERY WILL REMAIN GOOD. MODELS INDICATE HIGH PRESSURE WEAKENING THURSDAY AND FRIDAY BUT HIGH TEMPERATURES WILL STILL BE WELL ABOVE NORMAL. NORTHERLY BREEZINESS IS ANTICIPATED FRIDAY...MAINLY OVER SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...BUT NO STRONG WIND EVENTS ARE ANTICIPATED THROUGH THE PERIOD. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...MEYERS/LEINS AVIATION...AJ FIRE WEATHER...AJ
AREA FORECAST DISCUSSION
NWS TUCSON AZ
925 AM MST SAT MAR 1 2014 .SYNOPSIS...EXPECT VALLEY RAIN AND MOUNTAIN SNOW THROUGH TONIGHT... THEN PRECIPITATION WILL END FROM WEST TO EAST SUNDAY. STRONG AND GUSTY WINDS WILL OCCUR TODAY...ESPECIALLY SOUTHEAST OF TUCSON. MUCH COOLER TEMPERATURES WILL ALSO OCCUR THIS WEEKEND. THEREAFTER...DRY CONDITIONS WITH A WARMING TREND WILL PREVAIL DURING THE UPCOMING WEEK. && .DISCUSSION...KEMX WSR-88D DETECTED SCATTERED TO NUMEROUS 30-50 DBZ ECHOES GENERALLY NORTHWEST OF A KITT PEAK-TUCSON-SAN CARLOS RESERVOIR LINE AT 1620Z. MUCH OF THE REST OF SE AZ WAS VOID OF PRECIP ECHOES AT THIS TIME. ISOLATED THUNDERSTORMS HAVE ALSO OCCURRED DURING ABOUT THE PAST 30 MINS. AREAL COVERAGE OF PRECIP HAS GREATLY INCREASED DURING THE PAST 1-2 HOURS. DEWPOINTS VALID 16Z RANGED FROM THE MID 20S NEAR KDUG TO AROUND 50 F ACROSS WRN PIMA COUNTY. 01/12Z KTWC SOUNDING TOTAL PRECIP WATER VALUE WAS NEAR 0.90 INCH...AN INCREASE OF NEARLY 0.30 INCH DURING THE PAST 12 HOURS. 01/12Z UPPER AIR PLOTS INDICATED 538 DM LOW PRESSURE WAS CENTERED JUST OFF THE CENTRAL CALIFORNIA COAST. A VERY TIGHT MID-LEVEL GRADIENT WAS ACROSS SE AZ...WITH 700 MB 50 KT OBSERVED WIND SPEED AT KTWC. AREAL COVERAGE OF PRECIP IS EXPECTED TO INCREASE MARKEDLY DURING THE NEXT SEVERAL HOURS AS PER THE 01/14Z RUC HRRR. THE BULK OF THE PRECIP IS PROGGED TO EXPAND FROM GENERALLY FROM THE TUCSON METRO EWD/SWD...QUITE SIMILAR TO THE OFFICIAL FORECAST DEPICTION OF PRECIP. ISOLATED THUNDERSTORMS WILL ALSO OCCUR GIVEN THE MODEST CAPE ACROSS THE AREA. SNOW LEVELS AS PER RAWS OBSERVATIONS AND DUAL POL RADAR YIELDED ABOUT 8500-9000 FEET. THESE LEVELS ARE EXPECTED TO VERY GRADUALLY FALL TO NEAR 7500-8000 FEET FROM THE CATALINA MOUNTAINS NEWD TO THE WHITE MOUNTAINS BY THIS EVENING. GIVEN THE ONGOING PRECIP...BELIEVE HIGH TEMPS FROM TUCSON WWD ARE REASONABLE. THE UPSHOT...THERE ARE NO CHANGES FORTHCOMING TO THE OFFICIAL FORECAST AT THIS TIME. PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL. && .PREV DISCUSSION...THE CURRENT FORECAST STILL LOOKED IN GOOD SHAPE AS DEEPER MOISTURE CONTINUED TO ADVECT INTO ARIZONA AHEAD OF A STORM SYSTEM APPROACHING THE CENTRAL CALIFORNIA COAST EARLY THIS MORNING. RECENT MOSAIC RADAR IMAGERY WAS SHOWING SHOWERS AND A FEW THUNDERSTORMS IN WESTERN PIMA COUNTY. STILL EXPECTING SHOWERS AND THUNDERSTORMS TO DEVELOP AND SPREAD EASTWARD ACROSS SOUTHERN ARIZONA TODAY AS THE SYSTEM ENTERS SOUTHEASTERN CALIFORNIA. A WINTER STORM WARNING FOR HEAVY SNOW AND BLOWING SNOW WILL REMAIN IN EFFECT FROM 1 PM TODAY TO 10 AM MST SUNDAY ABOVE 7000 FEET FOR THE WHITE MOUNTAINS OF GRAHAM AND GREENLEE COUNTIES...AND THE GALIURO/PINALENO MOUNTAINS. A WINTER WEATHER ADVISORY FOR SNOW ALSO REMAINS IN EFFECT FROM 1 PM TODAY TO 10 AM MST SUNDAY ABOVE 7000 FEET FOR THE CATALINA/RINCON MOUNTAINS. TOTAL SNOW ACCUMULATIONS WITHIN THESE ZONES ARE FORECAST TO RANGE FROM 7 INCHES IN THE SOUTHERN MOST MOUNTAINS TO 22 INCHES ACROSS THE WHITE MOUNTAINS. SNOW LEVELS WILL BE NEAR 8000-8500 FEET BY MIDDAY TODAY THEN LOWER TO AROUND 6500 FEET BY SUNDAY MORNING. IN ADDITION TO THE PRECIPITATION...STRONG AND GUSTY WINDS WILL ACCOMPANY THE STORM TODAY ESPECIALLY EAST OF TUCSON. THAT SAID...A WIND ADVISORY ALSO IS IN EFFECT THROUGH 4 PM MST TODAY FOR SOUTHERN COCHISE COUNTY WHERE SOUTHWEST WINDS OF 25-35 MPH WITH GUSTS TO 45 MPH CAN BE EXPECTED. THE BULK OF PRECIPITATION WILL END BY SUNDAY EVENING...WITH DRY CONDITIONS PREVAILING THE REST OF THE WEEK. HIGH TEMPERATURES TODAY WILL BE ABOUT 10-15 DEGREES COOLER VERSUS TEMPERATURES OBSERVED YESTERDAY AFTERNOON...THEN ANOTHER 2-6 DEGREES OF COOLING SUNDAY. A WARMING TREND WILL FOLLOW THE REST OF THE WEEK. && .AVIATION...VALID THRU 02/18Z. VALLEY RAIN AND MOUNTAIN SNOW WILL OCCUR ACROSS SOUTHEAST ARIZONA THROUGH TONIGHT...THEN PRECIPITATION IS EXPECTED TO DIMINISH FROM WEST TO EAST SUNDAY MORNING. MVFR CONDITIONS WILL PREVAIL ESPECIALLY NEAR HIGHER TERRAIN DUE TO CLOUDS/PRECIP. ISOLATED -TSRA WILL ALSO OCCUR TODAY. SURFACE WIND THRU THIS EVENING GENERALLY SWLY/WLY AT 12-25 KTS WITH GUSTS TO NEAR 35 KTS. HOWEVER...EVEN STRONGER WIND SPEEDS WILL OCCUR ACROSS SOUTHERN COCHISE COUNTY THROUGH THIS AFTERNOON. THE KDUG TERMINAL MAY EXPERIENCE SUSTAINED WINDS OF 25-35 KTS WITH GUSTS TO AROUND 45 KTS. WINDS ARE EXPECTED TO DIMINISH TO MOSTLY LESS THAN 12 KTS LATE TONIGHT AND CONTINUE INTO SUNDAY MORNING. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...VALLEY RAIN AND MOUNTAIN SNOW WILL OCCUR THROUGH ABOUT MIDDAY SUNDAY...THEN SNOW SHOWERS WILL BE CONFINED MAINLY TO THE WHITE MOUNTAINS SUNDAY AFTERNOON AND SUNDAY NIGHT. STRONG AND GUSTY SOUTH TO SOUTHWEST WINDS WILL OCCUR TODAY...WITH THE STRONGEST WINDS ACROSS COCHISE COUNTY SOUTHEAST OF TUCSON. CRITICAL FIRE WEATHER CONDITIONS ARE NOT EXPECTED TO OCCUR DUE TO THE AMPLE MOISTURE. DRY CONDITIONS WILL PREVAIL ALONG WITH A WARMING TREND MONDAY THROUGH FRIDAY. && .TWC WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING FROM 1 PM THIS AFTERNOON TO 10 AM MST SUNDAY FOR AZZ510-511 ABOVE 7000 FEET. WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 10 AM MST SUNDAY FOR AZZ514 ABOVE 7000 FEET. WIND ADVISORY UNTIL 4 PM MST THIS AFTERNOON FOR AZZ507-508- 512-513. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON FRANCIS
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
615 AM MST SAT MAR 1 2014 .UPDATE... UPDATED AVIATION AND FIRE WEATHER SECTIONS. && .SYNOPSIS... A WELL DEFINED PACIFIC STORM SYSTEM WILL SLOWLY MOVE THROUGH THE AREA TODAY...EVENTUALLY BRINGING SHOWERS AND ISOLATED THUNDERSTORMS TO THE PHOENIX AREA. CONDITIONS WILL DRY OUT FROM WEST TO EAST THIS EVENING WITH NEARLY EVERYONE DRYING OUT COMPLETELY BY SUNDAY AFTERNOON. FOLLOWING THE LOW...DRY WEATHER IS EXPECTED ALONG WITH A RETURN TO ABOVE NORMAL TEMPERATURES BY LATE WEEK. && .DISCUSSION... FOR THOSE OF US IN THE PHOENIX AREA...THIS UPPER LOW HAS BEEN AN ABYSMAL UNDER-PERFORMER THUS FAR. UNLESS YOU WERE ONE OF THE LUCKY ONES CAUGHT UNDER A BRIEF SHOWER IN CAVE CREEK/CAREFREE FRIDAY EVENING...YOU HAVENT SEEN A DROP THUS FAR. WHILE SOUTHEAST CALIFORNIA AND WESTERN ARIZONA HAS FARED SOMEWHAT BETTER...RAINFALL STILL HASNT FILLED IN TO THE EXTENT THAT IT SHOULD HAVE. THAT BEING SAID...ALL HOPE IS NOT LOST...NOT BY A LONG-SHOT. THE 1+ INCH PWAT AXIS IS NOW SQUARELY POSITIONED OVERHEAD ALONG WITH 850-700MB WINDS AROUND 60-65KTS. NOT SURPRISINGLY...THOSE LOCATIONS DIRECTLY WITHIN THE UPSLOPE FLOW /FOOTHILLS AND HIGHER TERRAIN NORTH AND EAST OF PHOENIX/ ARE IN PRETTY GOOD SHAPE WITH THE REGIONAL RADAR MOSAIC FILLING IN QUITE A BIT SINCE MIDNIGHT. THERES EVEN A HINT AT NEW SHOWER DEVELOPMENT OVER THE FAR NORTH PART OF THE METRO /CEILINGS HAVE BEEN GRADUALLY LOWERING SINCE MIDNIGHT/ AND KYUX IS SHOWING SOME NEW ACTIVITY ACROSS FAR EASTERN YUMA/LA PAZ COUNTIES. WITH A SOLID 10-12HRS WORTH OF ANOMALOUSLY STRONG UPSLOPE WINDS FORECAST TO REMAIN IN PLACE OVER THE FORECAST AREA THROUGH 18Z COINCIDENT WITH AT LEAST 1.1 INCH PWATS...EVEN THE DRIEST MODELS ARE ADVERTISING CONVECTION TO DEVELOP AND FILL IN BY LATE MORNING...ALBEIT AT A GLACIAL PACE. ONCE THE COLD CORE ALOFT MOVES OVERHEAD BETWEEN 18Z AND 00Z...EXPECT ADDITIONAL DEVELOPMENT TO BLOSSOM ACROSS THE LOWER DESERTS AS MID LEVEL LAPSE RATES STEEPEN DRAMATICALLY. SOUTHEAST CALIFORNIA ISNT QUITE THROUGH WITH THE PRECIP BUT AS THEY WILL LOSE THEIR DEEPEST MOISTURE LATER THIS MORNING...THEIR POPS WILL BE A BIT LOWER THAN THOSE AROUND THE PHOENIX AREA. THUS...IM MAKING SOME ADJUSTMENTS TO POPS/QPF FOR THE ENTIRE FORECAST AREA. POPS/QPF WILL BE LOWERED A BIT ACROSS THE BOARD THROUGH LATE MORNING TO BETTER REFLECT WHAT HAS HAPPENED THUS FAR AND WHAT LITTLE IS DEVELOPING ON RADAR TO OUR SOUTH...BUT WILL BE RETAINED AROUND 100 PERCENT FOR LATE MORNING/AFTERNOON. GIVEN THEIR PERFORMANCE THUS FAR...THE HI-RES WRFS AND NAM 4KM NEST APPEAR TO HAVE THE BEST HANDLE ON THE SITUATION. HRRR AND RAP ARE SLOWLY CATCHING ONTO REALITY BUT NOT FAST ENOUGH TO BE USED FOR THIS MORNINGS FORECAST UNFORTUNATELY. COMPLETELY AVOIDING THE GFS EC AND GEM GIVEN THEIR LACKLUSTER PERFORMANCE THUS FAR. THE TROUGH AXIS PASSES OVERHEAD AROUND 06Z TONIGHT AND CONDITIONS SHOULD BEGIN DRYING OUT AS EARLY AS SUNDAY MORNING. FOR THE VAST MAJORITY OF THE LOWER DESERTS...SUNDAY MAY END UP TURNING OUT TO BE A PRETTY NICE DAY WITH GRADUALLY CLEARING SKIES BY EARLY AFTERNOON. SOUTHERN GILA COUNTY WILL LIKELY SEE SHOWERS HANG ON THE LONGEST...BUT EVEN THEY MAY END UP CLEARING OUT SOONER THAN LATER. POPS WERE ADJUSTED SLIGHTLY DOWNWARD ACROSS THE BOARD SUNDAY MORNING THROUGH SUNDAY AFTERNOON. AFTER THAT...ZONAL FLOW WILL ESTABLISH ITSELF ON MONDAY FOLLOWED BY WEAK MID-WEEK RIDGING. LOOK FOR TEMPERATURES TO SLOWLY RESPOND BACK TO NORMAL BY MID WEEK AND ABOVE NORMAL BY THE END OF THE WEEK. THERE IS SOME SUGGESTION OF A TROUGH MOVING THROUGH THE FOUR CORNERS LATE IN THE WEEK /FRIDAY OR SATURDAY/ BUT PRECIP POTENTIAL LOOKS MINIMAL GIVEN THE SOURCE REGION OF THE TROUGH. COULD BRING SOME BREEZINESS AND SLIGHTLY COOLER TEMPS BUT THAT LOOKS TO BE ABOUT IT. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... LOWER LEVEL MOISTURE AND SCATTERED SHOWERS ASSOCIATED WITH A PASSING FRONTAL ZONE HAS CAUSED CIGS TO LOWER TO 4-6 KFT MSL IN THE VICINITY OF THE SHOWERS...BRIEFLY LOWER IN SOME SPOTS. HOWEVER...CLOUD BASES ARE HIGHLY VARIABLE BETWEEN SHOWERS...ABOVE 6 KFT MSL OVER SOUTHEAST METRO PHOENIX AS OF 13Z. FLUCTUATING CIGS WITH PASSING SHOWERS IS ANTICIPATED TO CONTINUE THROUGH 16Z BEFORE SHOWERS TEMPORARILY DECREASE. ANTICIPATE RENEWED DEVELOPMENT THIS AFTERNOON AS THE UPPER LOW GETS CLOSER. ISOLATED T-STORMS POSSIBLE BUT CONFIDENCE TOO LOW AT ANY GIVEN SPOT TO REFLECT IN THE TAFS. ANTICIPATE SCATTERED SHOWERS TO CONTINUE INTO THE EVENING BEFORE TRAILING OFF OVERNIGHT. SOUTHWEST WINDS WILL PREVAIL WITH OCCASIONAL GUSTS TO 20 KTS. STRONGER SHOWERS COULD PRODUCE 25+ KTS. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... SHOWERS ARE STRUGGLING TO MAKE IT OVER THE COASTAL MOUNTAINS TO THE WEST. HRRR MODEL INDICATES ISOLATED SHOWER DEVELOPMENT AFTER 14Z INCREASING TO SCATTERED COVERAGE AFTER 20Z AND THIS IS REFLECTED IN THE TAFS. ISOLATED T-STORMS POSSIBLE BUT CONFIDENCE TOO LOW AT ANY GIVEN SPOT TO REFLECT IN THE TAFS. ANTICIPATE SCATTERED SHOWERS TO CONTINUE INTO THE EVENING BEFORE TRAILING OFF OVERNIGHT. LIGHT AND VARIABLE SURFACE WINDS WILL BECOME SOUTHWEST BY MIDDAY WITH OCCASIONAL GUSTS TO 20 KTS. STRONGER SHOWERS COULD PRODUCE 25+ KTS. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... MONDAY THROUGH FRIDAY... HIGH PRESSURE BUILDS BACK INTO THE REGION MONDAY THROUGH WEDNESDAY FOR A WARMING TREND ALONG WITH LESS WIND. HUMIDITIES WILL DECREASE THOUGH OVERNIGHT RECOVERY WILL REMAIN GOOD. MODELS INDICATE HIGH PRESSURE WEAKENING THURSDAY AND FRIDAY BUT HIGH TEMPERATURES WILL STILL BE WELL ABOVE NORMAL. NORTHERLY BREEZINESS IS ANTICIPATED FRIDAY...MAINLY OVER SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...BUT NO STRONG WIND EVENTS ARE ANTICIPATED THROUGH THE PERIOD. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...LEINS AVIATION...AJ FIRE WEATHER...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
235 AM MST SAT MAR 1 2014 .UPDATE UPDATED AVIATION SECTION. && .SYNOPSIS... A WELL DEFINED PACIFIC STORM SYSTEM WILL SLOWLY MOVE THROUGH THE AREA TODAY...EVENTUALLY BRINGING SHOWERS AND ISOLATED THUNDERSTORMS TO THE PHOENIX AREA. CONDITIONS WILL DRY OUT FROM WEST TO EAST THIS EVENING WITH NEARLY EVERYONE DRYING OUT COMPLETELY BY SUNDAY AFTERNOON. FOLLOWING THE LOW...DRY WEATHER IS EXPECTED ALONG WITH A RETURN TO ABOVE NORMAL TEMPERATURES BY LATE WEEK. && .DISCUSSION... FOR THOSE OF US IN THE PHOENIX AREA...THIS UPPER LOW HAS BEEN AN ABYSMAL UNDER-PERFORMER THUS FAR. UNLESS YOU WERE ONE OF THE LUCKY ONES CAUGHT UNDER A BRIEF SHOWER IN CAVE CREEK/CAREFREE FRIDAY EVENING...YOU HAVENT SEEN A DROP THUS FAR. WHILE SOUTHEAST CALIFORNIA AND WESTERN ARIZONA HAS FARED SOMEWHAT BETTER...RAINFALL STILL HASNT FILLED IN TO THE EXTENT THAT IT SHOULD HAVE. THAT BEING SAID...ALL HOPE IS NOT LOST...NOT BY A LONG-SHOT. THE 1+ INCH PWAT AXIS IS NOW SQUARELY POSITIONED OVERHEAD ALONG WITH 850-700MB WINDS AROUND 60-65KTS. NOT SURPRISINGLY...THOSE LOCATIONS DIRECTLY WITHIN THE UPSLOPE FLOW /FOOTHILLS AND HIGHER TERRAIN NORTH AND EAST OF PHOENIX/ ARE IN PRETTY GOOD SHAPE WITH THE REGIONAL RADAR MOSAIC FILLING IN QUITE A BIT SINCE MIDNIGHT. THERES EVEN A HINT AT NEW SHOWER DEVELOPMENT OVER THE FAR NORTH PART OF THE METRO /CEILINGS HAVE BEEN GRADUALLY LOWERING SINCE MIDNIGHT/ AND KYUX IS SHOWING SOME NEW ACTIVITY ACROSS FAR EASTERN YUMA/LA PAZ COUNTIES. WITH A SOLID 10-12HRS WORTH OF ANOMALOUSLY STRONG UPSLOPE WINDS FORECAST TO REMAIN IN PLACE OVER THE FORECAST AREA THROUGH 18Z COINCIDENT WITH AT LEAST 1.1 INCH PWATS...EVEN THE DRIEST MODELS ARE ADVERTISING CONVECTION TO DEVELOP AND FILL IN BY LATE MORNING...ALBEIT AT A GLACIAL PACE. ONCE THE COLD CORE ALOFT MOVES OVERHEAD BETWEEN 18Z AND 00Z...EXPECT ADDITIONAL DEVELOPMENT TO BLOSSOM ACROSS THE LOWER DESERTS AS MID LEVEL LAPSE RATES STEEPEN DRAMATICALLY. SOUTHEAST CALIFORNIA ISNT QUITE THROUGH WITH THE PRECIP BUT AS THEY WILL LOSE THEIR DEEPEST MOISTURE LATER THIS MORNING...THEIR POPS WILL BE A BIT LOWER THAN THOSE AROUND THE PHOENIX AREA. THUS...IM MAKING SOME ADJUSTMENTS TO POPS/QPF FOR THE ENTIRE FORECAST AREA. POPS/QPF WILL BE LOWERED A BIT ACROSS THE BOARD THROUGH LATE MORNING TO BETTER REFLECT WHAT HAS HAPPENED THUS FAR AND WHAT LITTLE IS DEVELOPING ON RADAR TO OUR SOUTH...BUT WILL BE RETAINED AROUND 100 PERCENT FOR LATE MORNING/AFTERNOON. GIVEN THEIR PERFORMANCE THUS FAR...THE HI-RES WRFS AND NAM 4KM NEST APPEAR TO HAVE THE BEST HANDLE ON THE SITUATION. HRRR AND RAP ARE SLOWLY CATCHING ONTO REALITY BUT NOT FAST ENOUGH TO BE USED FOR THIS MORNINGS FORECAST UNFORTUNATELY. COMPLETELY AVOIDING THE GFS EC AND GEM GIVEN THEIR LACKLUSTER PERFORMANCE THUS FAR. THE TROUGH AXIS PASSES OVERHEAD AROUND 06Z TONIGHT AND CONDITIONS SHOULD BEGIN DRYING OUT AS EARLY AS SUNDAY MORNING. FOR THE VAST MAJORITY OF THE LOWER DESERTS...SUNDAY MAY END UP TURNING OUT TO BE A PRETTY NICE DAY WITH GRADUALLY CLEARING SKIES BY EARLY AFTERNOON. SOUTHERN GILA COUNTY WILL LIKELY SEE SHOWERS HANG ON THE LONGEST...BUT EVEN THEY MAY END UP CLEARING OUT SOONER THAN LATER. POPS WERE ADJUSTED SLIGHTLY DOWNWARD ACROSS THE BOARD SUNDAY MORNING THROUGH SUNDAY AFTERNOON. AFTER THAT...ZONAL FLOW WILL ESTABLISH ITSELF ON MONDAY FOLLOWED BY WEAK MID-WEEK RIDGING. LOOK FOR TEMPERATURES TO SLOWLY RESPOND BACK TO NORMAL BY MID WEEK AND ABOVE NORMAL BY THE END OF THE WEEK. THERE IS SOME SUGGESTION OF A TROUGH MOVING THROUGH THE FOUR CORNERS LATE IN THE WEEK /FRIDAY OR SATURDAY/ BUT PRECIP POTENTIAL LOOKS MINIMAL GIVEN THE SOURCE REGION OF THE TROUGH. COULD BRING SOME BREEZINESS AND SLIGHTLY COOLER TEMPS BUT THAT LOOKS TO BE ABOUT IT. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... BAND OF LOW LEVEL MOISTURE MOVING ACROSS ARIZONA...ASSOCIATED WITH WEAKENING FRONT...HAS CAUSED CIGS TO LOWER TO 4-6 KFT MSL AS OF 09Z...INCLUDING METRO PHOENIX AREA. EXPECT THIS TO CONTINUE FOR REST OF THE DAY TODAY THOUGH SOME OCCASIONALLY HIGHER CIGS ARE QUITE LIKELY. SHOWERS HOWEVER HAVE BEEN MUCH LESS WIDESPREAD THAN PREVIOUSLY THOUGHT. HRRR MODEL HAS BEEN HANDLING THINGS WELL THE PAST SEVERAL HOURS AND LATEST RUN DEPICTS ONLY SOME SPOTTY SHOWER ACTIVITY OVER THE LOWER DESERTS UNTIL AT LEAST 16Z WHEN SHOWERS BECOME MORE NUMEROUS AS UPPER LOW APPROACHES. LATEST TAF AMENDMENTS REFLECT THAT THINKING. SOME LOCAL GUSTINESS OF 25-30 KTS IS POSSIBLE EVEN WITH GARDEN VARIETY SHOWERS. COULD SEE SOME STRAY T-STORMS MIDDAY ONWARD WHICH WOULD CREATE LOCALLY BRIEF HEAVY RAIN/SMALL HAIL...STRONG GUSTS...LOWERED VIS...AND EVEN LOWER CIGS BUT CONFIDENCE TOO LOW TO MENTION FOR ANY ONE TAF SITE AT THIS TIME. OTHERWISE...ANTICIPATE WINDS FROM 200-230 DEGREES TO PREVAIL WITH SOME OCCASIONAL GUSTS TO 20 KTS POSSIBLE. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... SHOWER ACTIVITY HAS TAPERED OFF AS SHOWERS ARE STRUGGLING TO MAKE IT OVER THE COASTAL MOUNTAINS. HRRR MODEL HAS CAPTURED TRENDS WELL OVER THE LAST SEVERAL HOURS AND IT DEPICTS ONLY VERY ISOLATED SHOWERS BEFORE 18Z FOLLOWED BY SCATTERED DEVELOPMENT FOR THE AFTERNOON. WEST AND SOUTHWEST WINDS WILL PREVAIL WITH SOME GUSTS OF 25-30 KTS POSSIBLE...MAINLY WEST OF LOWER COLORADO RIVER VALLEY. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... A LOW PRESSURE SYSTEM WILL EXIT THE FORECAST AREA SUNDAY. THERE WILL BE A LINGERING CHANCE OF SHOWERS SUNDAY...MAINLY OVER THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA. TEMPERATURES WILL STILL BE BELOW NORMAL SUNDAY AND HUMIDITIES WILL BE ELEVATED. HIGH PRESSURE BUILDS BACK INTO THE REGION MONDAY THROUGH THURSDAY FOR A WARMING TREND ALONG WITH LESS WIND. HUMIDITIES WILL DECREASE THOUGH OVERNIGHT RECOVERY WILL REMAIN GOOD. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...LEINS AVIATION...AJ FIRE WEATHER...AJ
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
123 AM MST SAT MAR 1 2014 .SYNOPSIS... A WELL DEFINED PACIFIC STORM SYSTEM WILL SLOWLY MOVE THROUGH THE AREA TODAY...EVENTUALLY BRINGING SHOWERS AND ISOLATED THUNDERSTORMS TO THE PHOENIX AREA. CONDITIONS WILL DRY OUT FROM WEST TO EAST THIS EVENING WITH NEARLY EVERYONE DRYING OUT COMPLETELY BY SUNDAY AFTERNOON. FOLLOWING THE LOW...DRY WEATHER IS EXPECTED ALONG WITH A RETURN TO ABOVE NORMAL TEMPERATURES BY LATE WEEK. && .DISCUSSION... FOR THOSE OF US IN THE PHOENIX AREA...THIS UPPER LOW HAS BEEN AN ABYSMAL UNDER-PERFORMER THUS FAR. UNLESS YOU WERE ONE OF THE LUCKY ONES CAUGHT UNDER A BRIEF SHOWER IN CAVE CREEK/CAREFREE FRIDAY EVENING...YOU HAVENT SEEN A DROP THUS FAR. WHILE SOUTHEAST CALIFORNIA AND WESTERN ARIZONA HAS FARED SOMEWHAT BETTER...RAINFALL STILL HASNT FILLED IN TO THE EXTENT THAT IT SHOULD HAVE. THAT BEING SAID...ALL HOPE IS NOT LOST...NOT BY A LONG-SHOT. THE 1+ INCH PWAT AXIS IS NOW SQUARELY POSITIONED OVERHEAD ALONG WITH 850-700MB WINDS AROUND 60-65KTS. NOT SURPRISINGLY...THOSE LOCATIONS DIRECTLY WITHIN THE UPSLOPE FLOW /FOOTHILLS AND HIGHER TERRAIN NORTH AND EAST OF PHOENIX/ ARE IN PRETTY GOOD SHAPE WITH THE REGIONAL RADAR MOSAIC FILLING IN QUITE A BIT SINCE MIDNIGHT. THERES EVEN A HINT AT NEW SHOWER DEVELOPMENT OVER THE FAR NORTH PART OF THE METRO /CEILINGS HAVE BEEN GRADUALLY LOWERING SINCE MIDNIGHT/ AND KYUX IS SHOWING SOME NEW ACTIVITY ACROSS FAR EASTERN YUMA/LA PAZ COUNTIES. WITH A SOLID 10-12HRS WORTH OF ANOMALOUSLY STRONG UPSLOPE WINDS FORECAST TO REMAIN IN PLACE OVER THE FORECAST AREA THROUGH 18Z COINCIDENT WITH AT LEAST 1.1 INCH PWATS...EVEN THE DRIEST MODELS ARE ADVERTISING CONVECTION TO DEVELOP AND FILL IN BY LATE MORNING...ALBEIT AT A GLACIAL PACE. ONCE THE COLD CORE ALOFT MOVES OVERHEAD BETWEEN 18Z AND 00Z...EXPECT ADDITIONAL DEVELOPMENT TO BLOSSOM ACROSS THE LOWER DESERTS AS MID LEVEL LAPSE RATES STEEPEN DRAMATICALLY. SOUTHEAST CALIFORNIA ISNT QUITE THROUGH WITH THE PRECIP BUT AS THEY WILL LOSE THEIR DEEPEST MOISTURE LATER THIS MORNING...THEIR POPS WILL BE A BIT LOWER THAN THOSE AROUND THE PHOENIX AREA. THUS...IM MAKING SOME ADJUSTMENTS TO POPS/QPF FOR THE ENTIRE FORECAST AREA. POPS/QPF WILL BE LOWERED A BIT ACROSS THE BOARD THROUGH LATE MORNING TO BETTER REFLECT WHAT HAS HAPPENED THUS FAR AND WHAT LITTLE IS DEVELOPING ON RADAR TO OUR SOUTH...BUT WILL BE RETAINED AROUND 100 PERCENT FOR LATE MORNING/AFTERNOON. GIVEN THEIR PERFORMANCE THUS FAR...THE HI-RES WRFS AND NAM 4KM NEST APPEAR TO HAVE THE BEST HANDLE ON THE SITUATION. HRRR AND RAP ARE SLOWLY CATCHING ONTO REALITY BUT NOT FAST ENOUGH TO BE USED FOR THIS MORNINGS FORECAST UNFORTUNATELY. COMPLETELY AVOIDING THE GFS EC AND GEM GIVEN THEIR LACKLUSTER PERFORMANCE THUS FAR. THE TROUGH AXIS PASSES OVERHEAD AROUND 06Z TONIGHT AND CONDITIONS SHOULD BEGIN DRYING OUT AS EARLY AS SUNDAY MORNING. FOR THE VAST MAJORITY OF THE LOWER DESERTS...SUNDAY MAY END UP TURNING OUT TO BE A PRETTY NICE DAY WITH GRADUALLY CLEARING SKIES BY EARLY AFTERNOON. SOUTHERN GILA COUNTY WILL LIKELY SEE SHOWERS HANG ON THE LONGEST...BUT EVEN THEY MAY END UP CLEARING OUT SOONER THAN LATER. POPS WERE ADJUSTED SLIGHTLY DOWNWARD ACROSS THE BOARD SUNDAY MORNING THROUGH SUNDAY AFTERNOON. AFTER THAT...ZONAL FLOW WILL ESTABLISH ITSELF ON MONDAY FOLLOWED BY WEAK MID-WEEK RIDGING. LOOK FOR TEMPERATURES TO SLOWLY RESPOND BACK TO NORMAL BY MID WEEK AND ABOVE NORMAL BY THE END OF THE WEEK. THERE IS SOME SUGGESTION OF A TROUGH MOVING THROUGH THE FOUR CORNERS LATE IN THE WEEK /FRIDAY OR SATURDAY/ BUT PRECIP POTENTIAL LOOKS MINIMAL GIVEN THE SOURCE REGION OF THE TROUGH. COULD BRING SOME BREEZINESS AND SLIGHTLY COOLER TEMPS BUT THAT LOOKS TO BE ABOUT IT. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... SOUTHERLY CROSS WINDS AT KPHX AND KIWA...OCCASIONALLY GUSTING AOA 20KT WILL BE ONE AVIATION CONCERN THROUGH THE ENTIRE NIGHT WITH THE STRONG PRESSURE GRADIENT NOT ALLOWING WINDS TO RELINQUISH THEIR GUSTY CHARACTER. INITIAL BANDS OF SHOWERS WILL REMAIN NORTH AND WEST OF CNTRL ARIZONA TERMINALS THROUGH THE EVENING...WITH BETTER CHANCES FOR MORE ORGANIZED SHOWERS AFTER 06Z. WHILE CHANCES FOR TS OVERNIGHT EXIST...PROBABILITIES ARE VERY LOW. THERE IS SOME MODEL INDICATIONS OF PERSISTENT CIGS FALLING INTO A 4K-5K FT LEVEL SAT MORNING AS SCT SHOWERS MAY LINGER IN THE VICINITY AFTER SUNRISE. THE BEST CHANCES FOR MDT/HVY SHOWERS WILL EXIST SAT AFTERNOON...THOUGH CIGS SHOULD RISE AOA 6K FT. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE AHEAD OF AN APPROACHING FRONTAL BOUNDARY THIS EVENING...WITH ACTIVITY EXPECTED TO MOVE EAST AFTER 03Z-06Z. WIND GUSTS TO AOA 25 KT WILL BE PREVALENT...THOUGH GUSTS APPROACHING 40KT WITH SHIFTING DIRECTION WILL BE POSSIBLE IN STRONGER SHOWERS. EMBEDDED ISOLD TS WILL ALSO BE POSSIBLE THIS EVENING. REDEVELOPMENT OF ISOLD/SCT SHOWERS MAY BE POSSIBLE SAT AFTERNOON...THOUGH CIGS THROUGH THE PERIOD SHOULD REMAIN AOA 6K FT. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... A LOW PRESSURE SYSTEM WILL EXIT THE FORECAST AREA SUNDAY. THERE WILL BE A LINGERING CHANCE OF SHOWERS SUNDAY...MAINLY OVER THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA. TEMPERATURES WILL STILL BE BELOW NORMAL SUNDAY AND HUMIDITIES WILL BE ELEVATED. HIGH PRESSURE BUILDS BACK INTO THE REGION MONDAY THROUGH THURSDAY FOR A WARMING TREND ALONG WITH LESS WIND. HUMIDITIES WILL DECREASE THOUGH OVERNIGHT RECOVERY WILL REMAIN GOOD. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...LEINS AVIATION...MO FIRE WEATHER...AJ
AREA FORECAST DISCUSSION
NWS RENO NV
850 PM PST FRI FEB 28 2014 .UPDATE... ONGOING FORECAST IS LARGELY ON TRACK FOR SNOWFALL AND TRENDS IN THE SIERRA, WHERE SNOW IS GRADUALLY TAPERING TO SHOWERS. WILL ALLOW WARNING AND ADVISORY FOR MONO CO AND TAHOE RESPECTIVELY, TO EXPIRE AT 10 PM. PERIODS OF LIGHT TO MODERATE SNOW SHOWERS ARE EXPECTED OVERNIGHT BUT ACCUMULATIONS SHOULD BE LIMITED TO AN INCH OR TWO MAINLY ALONG THE CREST. IN FACT, SNOW HAS REALLY STRUGGLED TO SPILL OVER INTO TRUCKEE/TAHOE LAST FEW HOURS. NOW, FURTHER NORTH GUIDANCE HAS BEEN INDICATING THE DEVELOPMENT OF A DEFORMATION BAND OF RAIN/SNOW NORTH OF SUSANVILLE-GERLACH FROM NOW UNTIL ABOUT 12Z/SAT. THE HRRR REALLY PICKS UP ON THIS AS DOES THE NAM, AND TO A LESSER EXTENT THE GFS. RADAR IS ALSO SHOWING A BAND IN THIS AREA, MOVING SLOWLY NORTH. FORECAST SOUNDINGS SHOW SNOW LEVELS DROPPING TO BELOW 5000 FEET. THIS PATTERN SEEMS FAVORABLE FOR SEVERAL INCHES OF SNOW ACCUMULATION FOR CEDARVILLE AND ADJACENT AREAS - SO WILL BE ISSUING AN OVERNIGHT ADVISORY FOR THOSE ZONES. REST OF FORECAST UNCHANGED. UPDATED PRODUCTS OUT SHORTLY. CS && .PREVIOUS DISCUSSION... /ISSUED 255 PM PST FRI FEB 28 2014/ SYNOPSIS... A WINTER STORM WILL CONTINUE TO PROVIDE PERIODS OF HEAVY SIERRA SNOWFALL THIS EVENING, PARTICULARLY IN MONO COUNTY. A MIX OF LIGHT RAIN AND SNOW SHOWERS THIS EVENING FOR WESTERN NEVADA. SHOWERS WILL DIMINISH BY SATURDAY AFTERNOON WITH ADDITIONAL WEAKER STORMS MOVING INTO THE WEST COAST NEXT WEEK. EACH WILL BRING THE POTENTIAL FOR SNOW IN THE SIERRA WITH RAIN SHOWERS FOR WESTERN NEVADA. SHORT TERM... AN OCCLUDED LOW OFF THE COAST CONTINUES TO STREAM MOISTURE ACROSS CENTRAL CALIFORNIA AND INTO THE SIERRA. THIS PROVIDED PERIODS OF HEAVY SNOWFALL ACROSS THE SIERRA PARTICULARLY IN MONO COUNTY. A TEMPORARY LULL IN SNOWFALL WILL PERSIST EARLY THIS AFTERNOON WITH ANOTHER PUSH OF HEAVIER SNOWFALL BEGINNING TO MOVE ACROSS THE SIERRA IN MONO COUNTY. TEMPERATURES IN THE SIERRA VALLEYS HAVE WARMED INTO THE LOW 40S BUT COULD SEE SNOW LEVELS EASILY FALL BACK TO LAKE LEVEL DUE TO THE CONVECTIVE NATURE OF THE INCOMING BANDS OF PRECIPITATION. COULD SEE AN ADDITIONAL 3-6" OF SNOW THROUGH THIS EVENING IN THE SIERRA ABOVE 7000 FEET WITH 6-9" IN MONO COUNTY. UP TO 3 INCHES OF ADDITIONAL SNOWFALL IS POSSIBLE FOR AREAS BELOW 7000 FEET. AREAS WITHIN CONVECTIVE BANDS COULD SEE RATES OF 3-4"/HR BUT PREDICTABILITY OF WHERE THEY DEVELOP IS LOW. AS SUCH, WILL ALLOW WINTER WARNING AND ADVISORIES TO CONTINUE INTO THIS EVENING. ACROSS WESTERN NEVADA MAINLY LIGHT SHOWERS WILL PERSIST THROUGH THIS EVENING WILL ONLY LIGHT RAIN AND SNOW ACCUMULATIONS EXPECTED WITH SNOW LEVELS GENERALLY AROUND 5500-6000 FEET THIS EVENING. SHOWERS WILL DIMINISH OVERNIGHT WITH SOME BANDED RAIN SHOWERS POSSIBLE ACROSS NORTHERN WASHOE AND CHURCHILL COUNTIES. ON SATURDAY THE UPPER LOW DROPS TO OUR SOUTH LEAVING US WITH MAINLY CLOUDY CONDITIONS. LINGERING SHOWERS POSSIBLE WITH ONLY ABOUT AN INCH OR TWO OF ADDITIONAL SNOWFALL POSSIBLE ALONG THE CREST AND FEW HUNDREDTHS OF AN INCH OF RAINFALL ACROSS WESTERN NEVADA. ON SUNDAY, FLOW TURNS ZONAL WITH MOSTLY CLOUDY CONDITIONS REMAINING WITH CHANCES FOR RAIN/SNOW SHOWERS MAINLY NORTH OF I-80 THROUGH WESTERN PORTIONS OF LASSEN COUNTY. FUENTES WARM BUT CLOUDY CONDITIONS SUNDAY NIGHT AND MONDAY AS THE MOIST ONSHORE FLOW CONTINUES. MODELS ARE VARYING ON THE TRACK OF WAVES MOVING INTO THE WEST COAST, BUT AT THIS TIME BEST CHANCE OF RAIN AND SNOW REMAINS NORTH OF INTERSTATE 80. THE WARM NATURE OF THE FLOW WILL KEEP SNOW LEVELS AT 6500-7500 FEET, WITH ONLY LIGHT SNOW ACCUMULATIONS POSSIBLE NEAR THE SIERRA CREST. BRONG LONG TERM...TUESDAY THROUGH FRIDAY... CHANCES FOR PRECIPITATION WERE CUT BACK TUESDAY AND WEDNESDAY, ESPECIALLY ALONG/SOUTH OF INTERSTATE 80, OTHERWISE NO SIGNIFICANT CHANGES TO THE LONG TERM FORECAST. TUESDAY AND WEDNESDAY, SHORTWAVE RIDGING IS PROJECTED BY MOST MODELS TO BUILD OVER THE SIERRA AND WESTERN NEVADA. THEREFORE, I TRENDED THE SHOWER COVERAGE FOR THOSE DAYS DOWN SLIGHTLY AND THEY COULD BE CUT BACK FURTHER IF THE MODELS/ENSEMBLES HOLD TRUE TO THE RIDGE CONCEPT. TEMPERATURES WILL BE MILD AT AROUND 10 DEGREES ABOVE AVERAGE. WEDNESDAY NIGHT AND THURSDAY, AN UPPER LOW MOVES INTO THE PACIFIC NORTHWEST AND SUPPRESSES THE UPPER RIDGE OVER THE REGION. WEDNESDAY NIGHT AND THURSDAY LOOKS TO BE BREEZY TO WINDY AS THE UPPER LOW MOVES INTO THE PACIFIC NORTHWEST AND PUSHES A COLD FRONT INTO NORTHERN CALIFORNIA AND NEVADA. PRECIPITATION-WISE, THE BEST UPPER FORCING IN THE 12Z GFS/ECMWF APPEARS TO REMAIN NORTH OF THE REGION. WITH THE UPPER FORCING REMAINING MOSTLY NORTH, A MODERATE MID LEVEL MOISTURE FEED MOVING IN AHEAD OF THE UPPER LOW COULD WEAKEN AND BECOME DISJOINTED WITH LOWER LEVEL MOISTURE AS IT MOVES INTO THE SIERRA/WESTERN NEVADA. STILL, THERE SHOULD BE AMPLE MOISTURE AND MID LEVEL FLOW TO PUSH PRECIPITATION OVER THE CREST INTO NORTHEAST CALIFORNIA (TAHOE NORTH). IT IS JUST FURTHER SOUTH AND EAST INTO MONO COUNTY AND WESTERN NEVADA THAT PRECIPITATION MAY BE SHADOWED SIGNIFICANTLY, SETTING UP MORE OF A WIND EVENT THAN ANYTHING ELSE. THURSDAY NIGHT AND FRIDAY, AN UPPER RIDGE IS EXPECTED TO BUILD BACK OVERHEAD FOR DRIER CONDITIONS. TEMPERATURES WILL BE KNOCKED DOWN BEHIND THURSDAY`S FRONT TO MORE SEASONAL NUMBERS IN THE 40S (SIERRA) AND 50S (LOWER VALLEYS). SNYDER && AVIATION... LOW PRESSURE OFF THE CENTRAL CALIFORNIA COAST WILL MOVE INLAND ON SATURDAY. FOR TONIGHT, SOUTHERLY FLOW IS PUSHING WIDESPREAD LIGHT TO MODERATE LOWER VALLEY RAIN AND MOUNTAIN SNOW INTO THE SIERRA AND FAR WESTERN NEVADA. PRECIPITATION WILL TAPER TO LIGHT SHOWERS, MAINLY IN THE SIERRA, BY LATE TONIGHT AND EARLY SATURDAY MORNING. FOR TONIGHT, THE MAIN CIG/VIS/PRECIPITATION CONCERN REMAINS IN THE SIERRA AND PERHAPS OUT INTO EXTREME WESTERN NEVADA SOUTH OF CARSON CITY/KCXP. WIDESPREAD TERRAIN OBSCURATION AND IFR/VIFR CIGS WILL PERSIST FOR MUCH OF THE NIGHT AS PRECIPITATION CONTINUES, ESPECIALLY SOUTH OF HIGHWAY 50 WHERE THE HEAVIEST PRECIPITATION IS LIKELY. AS FAR AS SNOWFALL AT TERMINALS, THE BEST SHOT FOR ACCUMULATING SNOWS ON UNTREATED SURFACES WILL BE AT KMMH AND KTVL THIS EVENING (AFTER 5 PM/01Z) WHEN THE HEAVIEST SNOW COMBINES WITH COOLING SURFACES NEAR SUNSET. BELOW ABOUT 5500 FEET TONIGHT, PRECIPITATION WILL REMAIN MOSTLY RAIN FOR LITTLE THREAT OF SNOW ACCUMULATIONS. OUT IN WESTERN NEVADA, THIS WILL MEAN THE BIGGEST IMPACT WILL BE HIGHER TERRAIN OBSCURATION. SNYDER && .REV WATCHES/WARNINGS/ADVISORIES... NV...WINTER WEATHER ADVISORY UNTIL 4 AM PST SATURDAY NVZ005. WINTER WEATHER ADVISORY UNTIL 10 PM PST THIS EVENING NVZ002. CA...WINTER WEATHER ADVISORY UNTIL 4 AM PST SATURDAY CAZ070. WINTER STORM WARNING UNTIL 10 PM PST THIS EVENING CAZ073. WINTER WEATHER ADVISORY UNTIL 10 PM PST THIS EVENING CAZ072. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1144 AM MST SAT MAR 1 2014 .UPDATE... ISSUED AT 1135 AM MST SAT MAR 1 2014 UPDATED FORECAST TO ADD WINTER WEATHER ADVISORY FOR THE FAR SOUTHEAST PLAINS WHERE A MIXTURE OF FREEZING DRIZZLE...SLEET...SNOW...AND FOG WILL CONTINUE WITH CONDITIONS WORSENING LATE THIS AFTERNOON THROUGH TONIGHT. SOME AREAS COULD PICK UP AN INCH OR TWO OF SNOW/SLEET ACCUMULATION...THOUGH ANY ICE ACCRETION SHOULD REMAIN LIGHT AND GENERALLY LESS THAN A TENTH OF AN INCH. STILL SOME UNCERTAINTIES FOR TOMORROW MORNING...WITH 12Z GFS SUGGESTING UP TO 4 INCHES OF SNOW WILL BE POSSIBLE OVER BACA COUNTY...WHILE NAM12 HAS CONSIDERABLY LESS. WILL CARRY THE WINTER WEATHER ADVISORY THROUGH 18Z FOR THOSE AREAS AND SEE HOW SHORT RES/HIGH RES MODELS EVOLVE ON THIS. FOR NOW...THINKING IS MORE IN THE REALM OF 1 TO 2 INCHES. MEANWHILE...SNOW WILL CONTINUE OUT WEST TODAY...WITH SIGNIFICANT ADDITIONAL ACCUMULATIONS ACROSS THE HIGHER ELEVATIONS. ALSO SEEING AREAS OF BLOWING DUST BEING REPORTED ALONG THE SOUTHERN I-25 CORRIDOR...SOUTH OF COLORADO CITY WHERE WINDS GUSTING TO AROUND 50 MPH FROM THE SOUTHWEST...AND TEMPERATURES HAVE ALREADY HIT THE LOWER 60S. HAVE PUT UP A BLOWING DUST ADVISORY FOR MAINLY HUERFANO AND WESTERN LAS ANIMAS COUNTIES...THOUGH AS WINDS SHIFT OUT OF THE EAST LATER THIS AFTERNOON THIS MAY END THE BLOWING DUST THREAT. -KT UPDATE ISSUED AT 930 AM MST SAT MAR 1 2014 UPDATED FORECAST SHORTLY BEFORE 9 AM TO EXTEND DENSE FOG ADVISORY FOR NORTHERN EL PASO COUNTY THROUGH 11 AM. ALSO ADDED SOUTHERN EL PASO COUNTY TO THE ADVISORY AS WEB CAMS SHOW VISIBILITIES...PARTICULARLY NEAR THE BROADMOOR AREA...AND ACROSS EASTERN PARTS OF THE COUNTY... LOOK FAIRLY LOW. ANTICIPATE THE WESTERLY WINDS WILL EAT AWAY AT THE STRATUS DECK ACROSS NORTHERN EL PASO COUNTY THROUGH THE LATE MORNING...BUT DENSE FREEZING FOG MAY CONTINUE ACROSS EASTERN PORTIONS OF EL PASO COUNTY WHERE SOUTHEAST UPSLOPE FLOW CONTINUES UNTIL 11 AM. FARTHER EAST...GETTING INCREASINGLY CONCERNED FOR THE POTENTIAL FOR A SLEET/SNOW MIX LATE THIS AFTERNOON AND EVENING. QUICK CALLS TO LAW ENFORCEMENT INDICATING THAT PCPN OUT THAT WAY IS VERY LIGHT AND NOT POSING PROBLEMS FOR THE ROADS JUST YET. FOG IS REDUCING VISIBILITIES TO AROUND A MILE OR LESS WITH ACCRETION OF ICE ON COLD SURFACES SUCH AS WIND SHIELDS. WILL BE INTERROGATING REMAINING 12Z RUNS THIS MORNING AND MAKING A DECISION ON A POSSIBLE WINTER WEATHER ADVISORY FOR FAR EASTERN PORTIONS OF THE DISTRICT. -KT UPDATE ISSUED AT 703 AM MST SAT MAR 1 2014 EXTENDED DENSE FOG ADVISORY UNTIL 9 AM. ALSO BROUGHT IN LATEST HRRR WINDS/TEMPS INTO NDFD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 405 AM MST SAT MAR 1 2014 ...SIGNIFICANT SNOWS ALONG THE CONTDVD...WIDE RANGING TEMPS ON THE PLAINS TODAY... CURRENTLY...AS OF 4 AM...COLD AIR HAS WORKED BACK TOWARDS THE MOUNTAINS. GENERALLY AREAS AOA 6000 FEET WERE IN THE COLD AIR (20S) WHILE ELEVATIONS ABOVE WERE IN THE WARM AIR (40S TO AROUND 50F). THE EXCEPTION TO THIS WAS N EL PASO COUNTY WHERE UPSLOPE FLOW WAS DRIVING THE LOW CLOUDS/FOG UP THE PALMER DVD. MTN VALLEYS WERE WARM AS BUENA VISTA...SALIDA AND A GOOD PART OF THE SAN LUIS VALLEY WERE ABOVE FREEZING (35-40F). HEAVY SNOW WAS LIKELY POUNDING THE MTNS (KGJT RADAR IS OUT OF COMMISSION AND WONT RETURN TO SERVICE UNTIL AT LEAST SUNDAY). WOLF CREEK OB HAS BEEN REPORTING HEAVY SNOW THROUGHOUT THE EARLY MORNING HOURS. IN ADDITION...WEB CAMS WERE SHOWING DENSE FOG ACROSS N EL PASO COUNTY. KCOS WAS ALSO REPORTING DENSE FOG. SOME FREEZING DRIZZLE WAS BEING OBSERVED AT SCHRIEVER AFB. TODAY... HEAVY SNOW WILL CONTINUE ACROSS THE CONTDVD TODAY. AN ADDITIONAL FOOT OF SNOW IS LIKELY ACROSS THE SAN JUANS WITH 6-12" ACROSS THE CENTRAL MTNS. HEAVY SNOW...5-10"...WILL OCCUR ACROSS THE TOP OF THE SANGRES. DENSE FOG WILL CONTINUE THIS EARLY MORNING ACROSS NORTHERN EL PASO COUNTY GIVEN THE STRONG UPSLOPE FLOW. TEMPS TODAY WILL VARY DRAMATICALLY ACROSS THE PLAINS. HI RES GUIDANCE INDICATES COLD AIR WILL BE PUSHED TO THE EAST...BUT I DO NOT THINK IT WILL GO AS FAR EAST AS GUIDANCE INDICATES. THE WARMEST AIR WILL LIKELY AFFECT THE PALMER DIVIDE AND AREAS ABOVE 5500 FEET ON THE PLAINS. MONUMENT HILL WILL LIKELY BE WARMER THAN DOWNTOWN COLORADO SPRINGS. PUEBLO WEST WILL BE WARMER THAN PUEBLO. WALSENBURG...TRINIDAD AND PINON CANYON WILL BE IN THE 60S WHILE EADS AND LAMAR WILL LIKELY REMAIN IN THE 20S. SPRINGFIELD WILL BE TRICKY...MAX TEMPS THERE I HAVE IN THE 40S...BUT IT IS NOT OUT OF THE QUESTION THAT THEY MAY NOT GET OUT OF THE 20S. BY LATE IN THE AFTERNOON WHEREVER THE BOUNDARY IS...IT WILL START TO WORK ITS WAY BACK TO THE WEST. AS FOR PRECIP ON THE PLAINS...THE OVERALL BEST CHANCE OF SOME PRECIP WILL BE ALONG THE CO/NM BORDER...BUT ALL AREAS MAY SEE PASSING SHOWERS LATER TODAY. PRECIP TYPE WILL BE DEPENDENT ON WHERE THE BOUNDARY LIES. FREEZING DRIZZLE WILL BE POSSIBLE TODAY WITH A BETTER CHANCE OF RAIN/SNOW LATER TODAY AS THE MOISTURE DEEPENS ACROSS THE PLAINS. THE BEST CHANCE FOR THE SAN LUIS VALLEY TO SEE PRECIP WILL BE TODAY...WITH THE BEST CHANCE OF PRECIP OVER THE SOUTHERN AND WESTERN PART OF THE VALLEY. TONIGHT... TROUGH ALOFT WILL MOVE ACROSS THE REGION. SNOWS WILL CONTINUE OVER THE MOUNTAINS. THE HEAVIEST SNOWS IN THE SAN JUANS WILL AFFECT AREAS JUST SOUTH OF WOLF CREEK PASS DOWN TO THE CO/NM BORDER. WITH FLOW TRANSITIONING TO MORE WEST NORTHWESTERLY...SNOWS WILL CONTINUE OVER THE CENTRAL MOUNTAINS. 4-8" WILL FALL IN THE SAN JUANS S OF WOLF CREEK...AND 3-7" WILL FALL IN THE C MTNS. A FEW MORE INCHES WILL FALL ON TOP OF THE SANGRES. THE PLAINS WILL SEE SNOW BUT OVERALL ACCUMS WILL GENERALLY BE LESS THAN AN INCH. THE HEAVIEST AMOUNTS WILL OCCUR OVER FAR SE CO. THE ENTIRE PLAINS WILL BE IN THE COLD UPSLOPE AND EXPECT CLOUDY SKIES WITH SINGLE DIGIT TEMPS OVER THE FAR E PLAINS AND TEENS ELSEWHERE. THE MTNS/VALLEYS WILL BE IN THE MID TEENS/20S FOR LOWS TONIGHT. /HODANISH .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 405 AM MST SAT MAR 1 2014 ...COLD SUNDAY... THE UPPER TROUGH AXIS WILL BE THROUGH CENTRAL CO AT 12Z SUN...AND NR THE KS BORDER BY 18Z. EXPECT RAPID DECREASE IN PRECIP ACROSS THE MT AREAS SUN MORNING...MAYBE EVEN SOME BREAKS IN THE CLOUDS...BUT SOME LIGHT ONGOING SNOW SHOWERS WILL BE LIKELY GIVEN INCREASED INSTABILITY. IF THERE ARE ANY BREAKS...THERE WILL BE RAPID REDEVELOPMENT OF CONVECTION OVER THE PEAKS SO CONTINUED HIGH POPS LOOK REASONABLE. ADDITIONAL ACCUMS WILL BE LIGHT FOR THE MTS...MAYBE AN INCH OR TWO. MAIN QUESTION SUNDAY WILL BE PRECIP FOR THE PLAINS. GIVEN THE TREND FOR A FASTER TROUGH PASSAGE...IT LOOKS LIKE THE MODELS ARE SHIFTING THE POTENTIAL FOR SNOW OVER THE PLAINS EWD...MAINLY INTO KS AND THE PANHANDLES SUN MORNING. THE NAM CONTINUES TO SHOW A MOSTLY DRY FORECAST EXCEPT NR THE KS BORDER. STILL SEE SOME POTENTIAL FOR BANDED SNOW OVR THE PLAINS...ESPECIALLY GIVEN THE CONVECTIVE NATURE OF THIS SYSTEM...SO WILL MAINTAIN CHANCE POPS MAINLY FOR THE MORNING HOURS AND AREAS E OF I-25. NOT READY TO THROW IN THE TOWEL QUITE YET FOR SN OVER THE I-25 ZONES. IT WILL DEFINITELY BE COLD ENOUGH...WITH SHALLOW COLD AIR FIRMLY IN PLACE AND TEMPS NOT LIKELY TO MAKE IT ABOVE FREEZING ANYWHERE OVER THE ERN PLAINS. WARMEST WX WILL BE IN THE HIGH VALLEYS WHICH COULD SEE SOME MID 40S. WE DRY OUT MON-TUE AS QUASI-ZONAL FLOW RESUMES OVER OUR AREA. A COUPLE WEAK DISTURBANCES MOVE THROUGH THE FLOW...THE FIRST MON AFTERNOON AND A SECOND TUE NIGHT. THESE COULD BRING SOME RENEWED SHSN TO THE MTS...ESPECIALLY THE CENTRAL MTS. THE GFS EVEN HINTS AT THE POSSIBILITY OF SOME LIGHT PRECIP OVER THE PLAINS LATE TUE OR EARLY WED...BUT WILL KEEP POPS SILENT FOR NOW. AFTER A DRY AND WARM THU...WITH TEMPS IN THE MID 60S OVER THE PLAINS...NEXT STORM SYSTEM ARRIVES FRI FROM THE NW. LOOKS LIKE ANOTHER FRONTAL PUSH IS POSSIBLE ACROSS THE PLAINS. IT IS STILL QUITE A WAYS OUT...SO WILL MAINTAIN POPS IN THE 20-30 PERCENT RANGE FOR THIS TIME PERIOD. THEN A HIGH AMPLITUDE RIDGE BUILDS...GIVING US A WARMER AND DRY NEXT WEEKEND. ROSE && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1038 AM MST SAT MAR 1 2014 IFR TO LIFR CONDITIONS WILL CONTINUE UNTIL AROUND 20Z FOR KCOS AND KPUB BEFORE FOG LIFTS AND CIGS RISE INTO THE MVFR CATEGORY. MEANWHILE LIFR CONDITIONS WILL CONTINUE ACROSS MUCH OF THE FAR SOUTHEAST PLAINS IN FZFG...FZDZ. SNOW...HEAVY AT TIMES WILL CONTINUE ACROSS THE MOUNTAIN AREAS WITH WIDESPREAD MTN OBSCURATIONS. KALS AND THE SOUTHERN I-25 CORRIDOR WILL SEE GUSTY SOUTHWEST WINDS (UP TO 40-45 KTS) AND CIGS MAINLY IN THE VFR CATEGORY...THOUGH SOME SCATTERED SHOWERS WILL MOVE OFF THE MOUNTAINS THIS AFTERNOON THROUGH THIS EVENING AND COULD BRING SOME BRIEF MVFR CIGS AT TIMES. STRATUS WILL SPREAD BACK WESTWARD ACROSS THE SOUTHEAST PLAINS WITH CIGS AND VIS DROPPING BACK INTO THE IFR TO LIFR CATEGORY DURING THE EVENING. AREAS OF FZDZ...SLEET...AND SNOW WILL BE POSSIBLE ACROSS THE FAR EASTERN PLAINS THIS EVENING WHERE CIGS AND VIS WILL REMAIN LIFR. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... BLOWING DUST ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR COZ087- 088. WINTER WEATHER ADVISORY UNTIL 11 AM MST SUNDAY FOR COZ095>099. WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ059-061-064- 067-073-075. WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066- 068. && $$ UPDATE...KT SHORT TERM...HODANISH LONG TERM...ROSE AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1043 AM MST SAT MAR 1 2014 .UPDATE... ISSUED AT 930 AM MST SAT MAR 1 2014 UPDATED FORECAST SHORTLY BEFORE 9 AM TO EXTEND DENSE FOG ADVISORY FOR NORTHERN EL PASO COUNTY THROUGH 11 AM. ALSO ADDED SOUTHERN EL PASO COUNTY TO THE ADVISORY AS WEB CAMS SHOW VISIBILITIES...PARTICULARLY NEAR THE BROADMOOR AREA...AND ACROSS EASTERN PARTS OF THE COUNTY... LOOK FAIRLY LOW. ANTICIPATE THE WESTERLY WINDS WILL EAT AWAY AT THE STRATUS DECK ACROSS NORTHERN EL PASO COUNTY THROUGH THE LATE MORNING...BUT DENSE FREEZING FOG MAY CONTINUE ACROSS EASTERN PORTIONS OF EL PASO COUNTY WHERE SOUTHEAST UPSLOPE FLOW CONTINUES UNTIL 11 AM. FARTHER EAST...GETTING INCREASINGLY CONCERNED FOR THE POTENTIAL FOR A SLEET/SNOW MIX LATE THIS AFTERNOON AND EVENING. QUICK CALLS TO LAW ENFORCEMENT INDICATING THAT PCPN OUT THAT WAY IS VERY LIGHT AND NOT POSING PROBLEMS FOR THE ROADS JUST YET. FOG IS REDUCING VISIBILITIES TO AROUND A MILE OR LESS WITH ACCRETION OF ICE ON COLD SURFACES SUCH AS WIND SHIELDS. WILL BE INTERROGATING REMAINING 12Z RUNS THIS MORNING AND MAKING A DECISION ON A POSSIBLE WINTER WEATHER ADVISORY FOR FAR EASTERN PORTIONS OF THE DISTRICT. -KT UPDATE ISSUED AT 703 AM MST SAT MAR 1 2014 EXTENDED DENSE FOG ADVISORY UNTIL 9 AM. ALSO BROUGHT IN LATEST HRRR WINDS/TEMPS INTO NDFD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 405 AM MST SAT MAR 1 2014 ...SIGNIFICANT SNOWS ALONG THE CONTDVD...WIDE RANGING TEMPS ON THE PLAINS TODAY... CURRENTLY...AS OF 4 AM...COLD AIR HAS WORKED BACK TOWARDS THE MOUNTAINS. GENERALLY AREAS AOA 6000 FEET WERE IN THE COLD AIR (20S) WHILE ELEVATIONS ABOVE WERE IN THE WARM AIR (40S TO AROUND 50F). THE EXCEPTION TO THIS WAS N EL PASO COUNTY WHERE UPSLOPE FLOW WAS DRIVING THE LOW CLOUDS/FOG UP THE PALMER DVD. MTN VALLEYS WERE WARM AS BUENA VISTA...SALIDA AND A GOOD PART OF THE SAN LUIS VALLEY WERE ABOVE FREEZING (35-40F). HEAVY SNOW WAS LIKELY POUNDING THE MTNS (KGJT RADAR IS OUT OF COMMISSION AND WONT RETURN TO SERVICE UNTIL AT LEAST SUNDAY). WOLF CREEK OB HAS BEEN REPORTING HEAVY SNOW THROUGHOUT THE EARLY MORNING HOURS. IN ADDITION...WEB CAMS WERE SHOWING DENSE FOG ACROSS N EL PASO COUNTY. KCOS WAS ALSO REPORTING DENSE FOG. SOME FREEZING DRIZZLE WAS BEING OBSERVED AT SCHRIEVER AFB. TODAY... HEAVY SNOW WILL CONTINUE ACROSS THE CONTDVD TODAY. AN ADDITIONAL FOOT OF SNOW IS LIKELY ACROSS THE SAN JUANS WITH 6-12" ACROSS THE CENTRAL MTNS. HEAVY SNOW...5-10"...WILL OCCUR ACROSS THE TOP OF THE SANGRES. DENSE FOG WILL CONTINUE THIS EARLY MORNING ACROSS NORTHERN EL PASO COUNTY GIVEN THE STRONG UPSLOPE FLOW. TEMPS TODAY WILL VARY DRAMATICALLY ACROSS THE PLAINS. HI RES GUIDANCE INDICATES COLD AIR WILL BE PUSHED TO THE EAST...BUT I DO NOT THINK IT WILL GO AS FAR EAST AS GUIDANCE INDICATES. THE WARMEST AIR WILL LIKELY AFFECT THE PALMER DIVIDE AND AREAS ABOVE 5500 FEET ON THE PLAINS. MONUMENT HILL WILL LIKELY BE WARMER THAN DOWNTOWN COLORADO SPRINGS. PUEBLO WEST WILL BE WARMER THAN PUEBLO. WALSENBURG...TRINIDAD AND PINON CANYON WILL BE IN THE 60S WHILE EADS AND LAMAR WILL LIKELY REMAIN IN THE 20S. SPRINGFIELD WILL BE TRICKY...MAX TEMPS THERE I HAVE IN THE 40S...BUT IT IS NOT OUT OF THE QUESTION THAT THEY MAY NOT GET OUT OF THE 20S. BY LATE IN THE AFTERNOON WHEREVER THE BOUNDARY IS...IT WILL START TO WORK ITS WAY BACK TO THE WEST. AS FOR PRECIP ON THE PLAINS...THE OVERALL BEST CHANCE OF SOME PRECIP WILL BE ALONG THE CO/NM BORDER...BUT ALL AREAS MAY SEE PASSING SHOWERS LATER TODAY. PRECIP TYPE WILL BE DEPENDENT ON WHERE THE BOUNDARY LIES. FREEZING DRIZZLE WILL BE POSSIBLE TODAY WITH A BETTER CHANCE OF RAIN/SNOW LATER TODAY AS THE MOISTURE DEEPENS ACROSS THE PLAINS. THE BEST CHANCE FOR THE SAN LUIS VALLEY TO SEE PRECIP WILL BE TODAY...WITH THE BEST CHANCE OF PRECIP OVER THE SOUTHERN AND WESTERN PART OF THE VALLEY. TONIGHT... TROUGH ALOFT WILL MOVE ACROSS THE REGION. SNOWS WILL CONTINUE OVER THE MOUNTAINS. THE HEAVIEST SNOWS IN THE SAN JUANS WILL AFFECT AREAS JUST SOUTH OF WOLF CREEK PASS DOWN TO THE CO/NM BORDER. WITH FLOW TRANSITIONING TO MORE WEST NORTHWESTERLY...SNOWS WILL CONTINUE OVER THE CENTRAL MOUNTAINS. 4-8" WILL FALL IN THE SAN JUANS S OF WOLF CREEK...AND 3-7" WILL FALL IN THE C MTNS. A FEW MORE INCHES WILL FALL ON TOP OF THE SANGRES. THE PLAINS WILL SEE SNOW BUT OVERALL ACCUMS WILL GENERALLY BE LESS THAN AN INCH. THE HEAVIEST AMOUNTS WILL OCCUR OVER FAR SE CO. THE ENTIRE PLAINS WILL BE IN THE COLD UPSLOPE AND EXPECT CLOUDY SKIES WITH SINGLE DIGIT TEMPS OVER THE FAR E PLAINS AND TEENS ELSEWHERE. THE MTNS/VALLEYS WILL BE IN THE MID TEENS/20S FOR LOWS TONIGHT. /HODANISH .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 405 AM MST SAT MAR 1 2014 ...COLD SUNDAY... THE UPPER TROUGH AXIS WILL BE THROUGH CENTRAL CO AT 12Z SUN...AND NR THE KS BORDER BY 18Z. EXPECT RAPID DECREASE IN PRECIP ACROSS THE MT AREAS SUN MORNING...MAYBE EVEN SOME BREAKS IN THE CLOUDS...BUT SOME LIGHT ONGOING SNOW SHOWERS WILL BE LIKELY GIVEN INCREASED INSTABILITY. IF THERE ARE ANY BREAKS...THERE WILL BE RAPID REDEVELOPMENT OF CONVECTION OVER THE PEAKS SO CONTINUED HIGH POPS LOOK REASONABLE. ADDITIONAL ACCUMS WILL BE LIGHT FOR THE MTS...MAYBE AN INCH OR TWO. MAIN QUESTION SUNDAY WILL BE PRECIP FOR THE PLAINS. GIVEN THE TREND FOR A FASTER TROUGH PASSAGE...IT LOOKS LIKE THE MODELS ARE SHIFTING THE POTENTIAL FOR SNOW OVER THE PLAINS EWD...MAINLY INTO KS AND THE PANHANDLES SUN MORNING. THE NAM CONTINUES TO SHOW A MOSTLY DRY FORECAST EXCEPT NR THE KS BORDER. STILL SEE SOME POTENTIAL FOR BANDED SNOW OVR THE PLAINS...ESPECIALLY GIVEN THE CONVECTIVE NATURE OF THIS SYSTEM...SO WILL MAINTAIN CHANCE POPS MAINLY FOR THE MORNING HOURS AND AREAS E OF I-25. NOT READY TO THROW IN THE TOWEL QUITE YET FOR SN OVER THE I-25 ZONES. IT WILL DEFINITELY BE COLD ENOUGH...WITH SHALLOW COLD AIR FIRMLY IN PLACE AND TEMPS NOT LIKELY TO MAKE IT ABOVE FREEZING ANYWHERE OVER THE ERN PLAINS. WARMEST WX WILL BE IN THE HIGH VALLEYS WHICH COULD SEE SOME MID 40S. WE DRY OUT MON-TUE AS QUASI-ZONAL FLOW RESUMES OVER OUR AREA. A COUPLE WEAK DISTURBANCES MOVE THROUGH THE FLOW...THE FIRST MON AFTERNOON AND A SECOND TUE NIGHT. THESE COULD BRING SOME RENEWED SHSN TO THE MTS...ESPECIALLY THE CENTRAL MTS. THE GFS EVEN HINTS AT THE POSSIBILITY OF SOME LIGHT PRECIP OVER THE PLAINS LATE TUE OR EARLY WED...BUT WILL KEEP POPS SILENT FOR NOW. AFTER A DRY AND WARM THU...WITH TEMPS IN THE MID 60S OVER THE PLAINS...NEXT STORM SYSTEM ARRIVES FRI FROM THE NW. LOOKS LIKE ANOTHER FRONTAL PUSH IS POSSIBLE ACROSS THE PLAINS. IT IS STILL QUITE A WAYS OUT...SO WILL MAINTAIN POPS IN THE 20-30 PERCENT RANGE FOR THIS TIME PERIOD. THEN A HIGH AMPLITUDE RIDGE BUILDS...GIVING US A WARMER AND DRY NEXT WEEKEND. ROSE && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1038 AM MST SAT MAR 1 2014 IFR TO LIFR CONDITIONS WILL CONTINUE UNTIL AROUND 20Z FOR KCOS AND KPUB BEFORE FOG LIFTS AND CIGS RISE INTO THE MVFR CATEGORY. MEANWHILE LIFR CONDITIONS WILL CONTINUE ACROSS MUCH OF THE FAR SOUTHEAST PLAINS IN FZFG...FZDZ. SNOW...HEAVY AT TIMES WILL CONTINUE ACROSS THE MOUNTAIN AREAS WITH WIDESPREAD MTN OBSCURATIONS. KALS AND THE SOUTHERN I-25 CORRIDOR WILL SEE GUSTY SOUTHWEST WINDS (UP TO 40-45 KTS) AND CIGS MAINLY IN THE VFR CATEGORY...THOUGH SOME SCATTERED SHOWERS WILL MOVE OFF THE MOUNTAINS THIS AFTERNOON THROUGH THIS EVENING AND COULD BRING SOME BRIEF MVFR CIGS AT TIMES. STRATUS WILL SPREAD BACK WESTWARD ACROSS THE SOUTHEAST PLAINS WITH CIGS AND VIS DROPPING BACK INTO THE IFR TO LIFR CATEGORY DURING THE EVENING. AREAS OF FZDZ...SLEET...AND SNOW WILL BE POSSIBLE ACROSS THE FAR EASTERN PLAINS THIS EVENING WHERE CIGS AND VIS WILL REMAIN LIFR. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 11 AM MST THIS MORNING FOR COZ084-085. WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ059-061-064- 067-073-075. BLOWING DUST ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR COZ087- 088. WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066- 068. && $$ UPDATE...KT SHORT TERM...HODANISH LONG TERM...ROSE AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
940 AM MST SAT MAR 1 2014 .UPDATE... ISSUED AT 930 AM MST SAT MAR 1 2014 UPDATED FORECAST SHORTLY BEFORE 9 AM TO EXTEND DENSE FOG ADVISORY FOR NORTHERN EL PASO COUNTY THROUGH 11 AM. ALSO ADDED SOUTHERN EL PASO COUNTY TO THE ADVISORY AS WEB CAMS SHOW VISIBILITIES...PARTICULARLY NEAR THE BROADMOOR AREA...AND ACROSS EASTERN PARTS OF THE COUNTY... LOOK FAIRLY LOW. ANTICIPATE THE WESTERLY WINDS WILL EAT AWAY AT THE STRATUS DECK ACROSS NORTHERN EL PASO COUNTY THROUGH THE LATE MORNING...BUT DENSE FREEZING FOG MAY CONTINUE ACROSS EASTERN PORTIONS OF EL PASO COUNTY WHERE SOUTHEAST UPSLOPE FLOW CONTINUES UNTIL 11 AM. FARTHER EAST...GETTING INCREASINGLY CONCERNED FOR THE POTENTIAL FOR A SLEET/SNOW MIX LATE THIS AFTERNOON AND EVENING. QUICK CALLS TO LAW ENFORCEMENT INDICATING THAT PCPN OUT THAT WAY IS VERY LIGHT AND NOT POSING PROBLEMS FOR THE ROADS JUST YET. FOG IS REDUCING VISIBILITIES TO AROUND A MILE OR LESS WITH ACCRETION OF ICE ON COLD SURFACES SUCH AS WIND SHIELDS. WILL BE INTERROGATING REMAINING 12Z RUNS THIS MORNING AND MAKING A DECISION ON A POSSIBLE WINTER WEATHER ADVISORY FOR FAR EASTERN PORTIONS OF THE DISTRICT. -KT UPDATE ISSUED AT 703 AM MST SAT MAR 1 2014 EXTENDED DENSE FOG ADVISORY UNTIL 9 AM. ALSO BROUGHT IN LATEST HRRR WINDS/TEMPS INTO NDFD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 405 AM MST SAT MAR 1 2014 ...SIGNIFICANT SNOWS ALONG THE CONTDVD...WIDE RANGING TEMPS ON THE PLAINS TODAY... CURRENTLY...AS OF 4 AM...COLD AIR HAS WORKED BACK TOWARDS THE MOUNTAINS. GENERALLY AREAS AOA 6000 FEET WERE IN THE COLD AIR (20S) WHILE ELEVATIONS ABOVE WERE IN THE WARM AIR (40S TO AROUND 50F). THE EXCEPTION TO THIS WAS N EL PASO COUNTY WHERE UPSLOPE FLOW WAS DRIVING THE LOW CLOUDS/FOG UP THE PALMER DVD. MTN VALLEYS WERE WARM AS BUENA VISTA...SALIDA AND A GOOD PART OF THE SAN LUIS VALLEY WERE ABOVE FREEZING (35-40F). HEAVY SNOW WAS LIKELY POUNDING THE MTNS (KGJT RADAR IS OUT OF COMMISSION AND WONT RETURN TO SERVICE UNTIL AT LEAST SUNDAY). WOLF CREEK OB HAS BEEN REPORTING HEAVY SNOW THROUGHOUT THE EARLY MORNING HOURS. IN ADDITION...WEB CAMS WERE SHOWING DENSE FOG ACROSS N EL PASO COUNTY. KCOS WAS ALSO REPORTING DENSE FOG. SOME FREEZING DRIZZLE WAS BEING OBSERVED AT SCHRIEVER AFB. TODAY... HEAVY SNOW WILL CONTINUE ACROSS THE CONTDVD TODAY. AN ADDITIONAL FOOT OF SNOW IS LIKELY ACROSS THE SAN JUANS WITH 6-12" ACROSS THE CENTRAL MTNS. HEAVY SNOW...5-10"...WILL OCCUR ACROSS THE TOP OF THE SANGRES. DENSE FOG WILL CONTINUE THIS EARLY MORNING ACROSS NORTHERN EL PASO COUNTY GIVEN THE STRONG UPSLOPE FLOW. TEMPS TODAY WILL VARY DRAMATICALLY ACROSS THE PLAINS. HI RES GUIDANCE INDICATES COLD AIR WILL BE PUSHED TO THE EAST...BUT I DO NOT THINK IT WILL GO AS FAR EAST AS GUIDANCE INDICATES. THE WARMEST AIR WILL LIKELY AFFECT THE PALMER DIVIDE AND AREAS ABOVE 5500 FEET ON THE PLAINS. MONUMENT HILL WILL LIKELY BE WARMER THAN DOWNTOWN COLORADO SPRINGS. PUEBLO WEST WILL BE WARMER THAN PUEBLO. WALSENBURG...TRINIDAD AND PINON CANYON WILL BE IN THE 60S WHILE EADS AND LAMAR WILL LIKELY REMAIN IN THE 20S. SPRINGFIELD WILL BE TRICKY...MAX TEMPS THERE I HAVE IN THE 40S...BUT IT IS NOT OUT OF THE QUESTION THAT THEY MAY NOT GET OUT OF THE 20S. BY LATE IN THE AFTERNOON WHEREVER THE BOUNDARY IS...IT WILL START TO WORK ITS WAY BACK TO THE WEST. AS FOR PRECIP ON THE PLAINS...THE OVERALL BEST CHANCE OF SOME PRECIP WILL BE ALONG THE CO/NM BORDER...BUT ALL AREAS MAY SEE PASSING SHOWERS LATER TODAY. PRECIP TYPE WILL BE DEPENDENT ON WHERE THE BOUNDARY LIES. FREEZING DRIZZLE WILL BE POSSIBLE TODAY WITH A BETTER CHANCE OF RAIN/SNOW LATER TODAY AS THE MOISTURE DEEPENS ACROSS THE PLAINS. THE BEST CHANCE FOR THE SAN LUIS VALLEY TO SEE PRECIP WILL BE TODAY...WITH THE BEST CHANCE OF PRECIP OVER THE SOUTHERN AND WESTERN PART OF THE VALLEY. TONIGHT... TROUGH ALOFT WILL MOVE ACROSS THE REGION. SNOWS WILL CONTINUE OVER THE MOUNTAINS. THE HEAVIEST SNOWS IN THE SAN JUANS WILL AFFECT AREAS JUST SOUTH OF WOLF CREEK PASS DOWN TO THE CO/NM BORDER. WITH FLOW TRANSITIONING TO MORE WEST NORTHWESTERLY...SNOWS WILL CONTINUE OVER THE CENTRAL MOUNTAINS. 4-8" WILL FALL IN THE SAN JUANS S OF WOLF CREEK...AND 3-7" WILL FALL IN THE C MTNS. A FEW MORE INCHES WILL FALL ON TOP OF THE SANGRES. THE PLAINS WILL SEE SNOW BUT OVERALL ACCUMS WILL GENERALLY BE LESS THAN AN INCH. THE HEAVIEST AMOUNTS WILL OCCUR OVER FAR SE CO. THE ENTIRE PLAINS WILL BE IN THE COLD UPSLOPE AND EXPECT CLOUDY SKIES WITH SINGLE DIGIT TEMPS OVER THE FAR E PLAINS AND TEENS ELSEWHERE. THE MTNS/VALLEYS WILL BE IN THE MID TEENS/20S FOR LOWS TONIGHT. /HODANISH .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 405 AM MST SAT MAR 1 2014 ...COLD SUNDAY... THE UPPER TROUGH AXIS WILL BE THROUGH CENTRAL CO AT 12Z SUN...AND NR THE KS BORDER BY 18Z. EXPECT RAPID DECREASE IN PRECIP ACROSS THE MT AREAS SUN MORNING...MAYBE EVEN SOME BREAKS IN THE CLOUDS...BUT SOME LIGHT ONGOING SNOW SHOWERS WILL BE LIKELY GIVEN INCREASED INSTABILITY. IF THERE ARE ANY BREAKS...THERE WILL BE RAPID REDEVELOPMENT OF CONVECTION OVER THE PEAKS SO CONTINUED HIGH POPS LOOK REASONABLE. ADDITIONAL ACCUMS WILL BE LIGHT FOR THE MTS...MAYBE AN INCH OR TWO. MAIN QUESTION SUNDAY WILL BE PRECIP FOR THE PLAINS. GIVEN THE TREND FOR A FASTER TROUGH PASSAGE...IT LOOKS LIKE THE MODELS ARE SHIFTING THE POTENTIAL FOR SNOW OVER THE PLAINS EWD...MAINLY INTO KS AND THE PANHANDLES SUN MORNING. THE NAM CONTINUES TO SHOW A MOSTLY DRY FORECAST EXCEPT NR THE KS BORDER. STILL SEE SOME POTENTIAL FOR BANDED SNOW OVR THE PLAINS...ESPECIALLY GIVEN THE CONVECTIVE NATURE OF THIS SYSTEM...SO WILL MAINTAIN CHANCE POPS MAINLY FOR THE MORNING HOURS AND AREAS E OF I-25. NOT READY TO THROW IN THE TOWEL QUITE YET FOR SN OVER THE I-25 ZONES. IT WILL DEFINITELY BE COLD ENOUGH...WITH SHALLOW COLD AIR FIRMLY IN PLACE AND TEMPS NOT LIKELY TO MAKE IT ABOVE FREEZING ANYWHERE OVER THE ERN PLAINS. WARMEST WX WILL BE IN THE HIGH VALLEYS WHICH COULD SEE SOME MID 40S. WE DRY OUT MON-TUE AS QUASI-ZONAL FLOW RESUMES OVER OUR AREA. A COUPLE WEAK DISTURBANCES MOVE THROUGH THE FLOW...THE FIRST MON AFTERNOON AND A SECOND TUE NIGHT. THESE COULD BRING SOME RENEWED SHSN TO THE MTS...ESPECIALLY THE CENTRAL MTS. THE GFS EVEN HINTS AT THE POSSIBILITY OF SOME LIGHT PRECIP OVER THE PLAINS LATE TUE OR EARLY WED...BUT WILL KEEP POPS SILENT FOR NOW. AFTER A DRY AND WARM THU...WITH TEMPS IN THE MID 60S OVER THE PLAINS...NEXT STORM SYSTEM ARRIVES FRI FROM THE NW. LOOKS LIKE ANOTHER FRONTAL PUSH IS POSSIBLE ACROSS THE PLAINS. IT IS STILL QUITE A WAYS OUT...SO WILL MAINTAIN POPS IN THE 20-30 PERCENT RANGE FOR THIS TIME PERIOD. THEN A HIGH AMPLITUDE RIDGE BUILDS...GIVING US A WARMER AND DRY NEXT WEEKEND. ROSE && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 405 AM MST SAT MAR 1 2014 VFR CONDITIONS WILL OCCUR ACROSS THE 3 TAF SITES...KPUB...KCOS AND KALS NEXT 24H. MAIN CONCERN TODAY AT KCOS AND ESPECIALLY KPUB WILL BE GUSTY WEST TO NORTHWEST WINDS AT 15 TO 30 KNOTS. KALS MAY HAVE -SN VCNTY TOWARDS SUNRISE TOMORROW. THERE IS A VERY LOW CHANCE THAT SOME FOG COULD DEVELOP AT KCOS AND KPUB AROUND SUNRISE TOMORROW. && .PUB WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 11 AM MST THIS MORNING FOR COZ084-085. WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ059-061-064- 067-073-075. WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066- 068. && $$ UPDATE...KT SHORT TERM...HODANISH LONG TERM...ROSE AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
704 AM MST SAT MAR 1 2014 .UPDATE... ISSUED AT 703 AM MST SAT MAR 1 2014 EXTENDED DENSE FOG ADVISORY UNTIL 9 AM. ALSO BROUGHT IN LATEST HRRR WINDS/TEMPS INTO NDFD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 405 AM MST SAT MAR 1 2014 ...SIGNIFICANT SNOWS ALONG THE CONTDVD...WIDE RANGING TEMPS ON THE PLAINS TODAY... CURRENTLY...AS OF 4 AM...COLD AIR HAS WORKED BACK TOWARDS THE MOUNTAINS. GENERALLY AREAS AOA 6000 FEET WERE IN THE COLD AIR (20S) WHILE ELEVATIONS ABOVE WERE IN THE WARM AIR (40S TO AROUND 50F). THE EXCEPTION TO THIS WAS N EL PASO COUNTY WHERE UPSLOPE FLOW WAS DRIVING THE LOW CLOUDS/FOG UP THE PALMER DVD. MTN VALLEYS WERE WARM AS BUENA VISTA...SALIDA AND A GOOD PART OF THE SAN LUIS VALLEY WERE ABOVE FREEZING (35-40F). HEAVY SNOW WAS LIKELY POUNDING THE MTNS (KGJT RADAR IS OUT OF COMMISSION AND WONT RETURN TO SERVICE UNTIL AT LEAST SUNDAY). WOLF CREEK OB HAS BEEN REPORTING HEAVY SNOW THROUGHOUT THE EARLY MORNING HOURS. IN ADDITION...WEB CAMS WERE SHOWING DENSE FOG ACROSS N EL PASO COUNTY. KCOS WAS ALSO REPORTING DENSE FOG. SOME FREEZING DRIZZLE WAS BEING OBSERVED AT SCHRIEVER AFB. TODAY... HEAVY SNOW WILL CONTINUE ACROSS THE CONTDVD TODAY. AN ADDITIONAL FOOT OF SNOW IS LIKELY ACROSS THE SAN JUANS WITH 6-12" ACROSS THE CENTRAL MTNS. HEAVY SNOW...5-10"...WILL OCCUR ACROSS THE TOP OF THE SANGRES. DENSE FOG WILL CONTINUE THIS EARLY MORNING ACROSS NORTHERN EL PASO COUNTY GIVEN THE STRONG UPSLOPE FLOW. TEMPS TODAY WILL VARY DRAMATICALLY ACROSS THE PLAINS. HI RES GUIDANCE INDICATES COLD AIR WILL BE PUSHED TO THE EAST...BUT I DO NOT THINK IT WILL GO AS FAR EAST AS GUIDANCE INDICATES. THE WARMEST AIR WILL LIKELY AFFECT THE PALMER DIVIDE AND AREAS ABOVE 5500 FEET ON THE PLAINS. MONUMENT HILL WILL LIKELY BE WARMER THAN DOWNTOWN COLORADO SPRINGS. PUEBLO WEST WILL BE WARMER THAN PUEBLO. WALSENBURG...TRINIDAD AND PINON CANYON WILL BE IN THE 60S WHILE EADS AND LAMAR WILL LIKELY REMAIN IN THE 20S. SPRINGFIELD WILL BE TRICKY...MAX TEMPS THERE I HAVE IN THE 40S...BUT IT IS NOT OUT OF THE QUESTION THAT THEY MAY NOT GET OUT OF THE 20S. BY LATE IN THE AFTERNOON WHEREVER THE BOUNDARY IS...IT WILL START TO WORK ITS WAY BACK TO THE WEST. AS FOR PRECIP ON THE PLAINS...THE OVERALL BEST CHANCE OF SOME PRECIP WILL BE ALONG THE CO/NM BORDER...BUT ALL AREAS MAY SEE PASSING SHOWERS LATER TODAY. PRECIP TYPE WILL BE DEPENDENT ON WHERE THE BOUNDARY LIES. FREEZING DRIZZLE WILL BE POSSIBLE TODAY WITH A BETTER CHANCE OF RAIN/SNOW LATER TODAY AS THE MOISTURE DEEPENS ACROSS THE PLAINS. THE BEST CHANCE FOR THE SAN LUIS VALLEY TO SEE PRECIP WILL BE TODAY...WITH THE BEST CHANCE OF PRECIP OVER THE SOUTHERN AND WESTERN PART OF THE VALLEY. TONIGHT... TROUGH ALOFT WILL MOVE ACROSS THE REGION. SNOWS WILL CONTINUE OVER THE MOUNTAINS. THE HEAVIEST SNOWS IN THE SAN JUANS WILL AFFECT AREAS JUST SOUTH OF WOLF CREEK PASS DOWN TO THE CO/NM BORDER. WITH FLOW TRANSITIONING TO MORE WEST NORTHWESTERLY...SNOWS WILL CONTINUE OVER THE CENTRAL MOUNTAINS. 4-8" WILL FALL IN THE SAN JUANS S OF WOLF CREEK...AND 3-7" WILL FALL IN THE C MTNS. A FEW MORE INCHES WILL FALL ON TOP OF THE SANGRES. THE PLAINS WILL SEE SNOW BUT OVERALL ACCUMS WILL GENERALLY BE LESS THAN AN INCH. THE HEAVIEST AMOUNTS WILL OCCUR OVER FAR SE CO. THE ENTIRE PLAINS WILL BE IN THE COLD UPSLOPE AND EXPECT CLOUDY SKIES WITH SINGLE DIGIT TEMPS OVER THE FAR E PLAINS AND TEENS ELSEWHERE. THE MTNS/VALLEYS WILL BE IN THE MID TEENS/20S FOR LOWS TONIGHT. /HODANISH .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 405 AM MST SAT MAR 1 2014 ...COLD SUNDAY... THE UPPER TROUGH AXIS WILL BE THROUGH CENTRAL CO AT 12Z SUN...AND NR THE KS BORDER BY 18Z. EXPECT RAPID DECREASE IN PRECIP ACROSS THE MT AREAS SUN MORNING...MAYBE EVEN SOME BREAKS IN THE CLOUDS...BUT SOME LIGHT ONGOING SNOW SHOWERS WILL BE LIKELY GIVEN INCREASED INSTABILITY. IF THERE ARE ANY BREAKS...THERE WILL BE RAPID REDEVELOPMENT OF CONVECTION OVER THE PEAKS SO CONTINUED HIGH POPS LOOK REASONABLE. ADDITIONAL ACCUMS WILL BE LIGHT FOR THE MTS...MAYBE AN INCH OR TWO. MAIN QUESTION SUNDAY WILL BE PRECIP FOR THE PLAINS. GIVEN THE TREND FOR A FASTER TROUGH PASSAGE...IT LOOKS LIKE THE MODELS ARE SHIFTING THE POTENTIAL FOR SNOW OVER THE PLAINS EWD...MAINLY INTO KS AND THE PANHANDLES SUN MORNING. THE NAM CONTINUES TO SHOW A MOSTLY DRY FORECAST EXCEPT NR THE KS BORDER. STILL SEE SOME POTENTIAL FOR BANDED SNOW OVR THE PLAINS...ESPECIALLY GIVEN THE CONVECTIVE NATURE OF THIS SYSTEM...SO WILL MAINTAIN CHANCE POPS MAINLY FOR THE MORNING HOURS AND AREAS E OF I-25. NOT READY TO THROW IN THE TOWEL QUITE YET FOR SN OVER THE I-25 ZONES. IT WILL DEFINITELY BE COLD ENOUGH...WITH SHALLOW COLD AIR FIRMLY IN PLACE AND TEMPS NOT LIKELY TO MAKE IT ABOVE FREEZING ANYWHERE OVER THE ERN PLAINS. WARMEST WX WILL BE IN THE HIGH VALLEYS WHICH COULD SEE SOME MID 40S. WE DRY OUT MON-TUE AS QUASI-ZONAL FLOW RESUMES OVER OUR AREA. A COUPLE WEAK DISTURBANCES MOVE THROUGH THE FLOW...THE FIRST MON AFTERNOON AND A SECOND TUE NIGHT. THESE COULD BRING SOME RENEWED SHSN TO THE MTS...ESPECIALLY THE CENTRAL MTS. THE GFS EVEN HINTS AT THE POSSIBILITY OF SOME LIGHT PRECIP OVER THE PLAINS LATE TUE OR EARLY WED...BUT WILL KEEP POPS SILENT FOR NOW. AFTER A DRY AND WARM THU...WITH TEMPS IN THE MID 60S OVER THE PLAINS...NEXT STORM SYSTEM ARRIVES FRI FROM THE NW. LOOKS LIKE ANOTHER FRONTAL PUSH IS POSSIBLE ACROSS THE PLAINS. IT IS STILL QUITE A WAYS OUT...SO WILL MAINTAIN POPS IN THE 20-30 PERCENT RANGE FOR THIS TIME PERIOD. THEN A HIGH AMPLITUDE RIDGE BUILDS...GIVING US A WARMER AND DRY NEXT WEEKEND. ROSE && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 405 AM MST SAT MAR 1 2014 VFR CONDITIONS WILL OCCUR ACROSS THE 3 TAF SITES...KPUB...KCOS AND KALS NEXT 24H. MAIN CONCERN TODAY AT KCOS AND ESPECIALLY KPUB WILL BE GUSTY WEST TO NORTHWEST WINDS AT 15 TO 30 KNOTS. KALS MAY HAVE -SN VCNTY TOWARDS SUNRISE TOMORROW. THERE IS A VERY LOW CHANCE THAT SOME FOG COULD DEVELOP AT KCOS AND KPUB AROUND SUNRISE TOMORROW. && .PUB WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 9 AM MST THIS MORNING FOR COZ084. WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR COZ059-061-064- 067-073-075. WINTER STORM WARNING UNTIL 5 AM MST SUNDAY FOR COZ058-060-066- 068. && $$ UPDATE...HODANISH SHORT TERM...HODANISH LONG TERM...ROSE AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS TAUNTON MA
714 PM EST SUN MAR 2 2014 .SYNOPSIS... A COLD FRONT WILL CONTINUE TO SLIDE OFFSHORE...STALLING WELL SOUTH OF THE REGION TONIGHT. LOW PRESSURE WILL MOVE ALONG THE FRONT...BRUSHING THE SOUTH COAST WITH ACCUMULATING SNOW. THEREAFTER DRY BUT MUCH COLDER THAN NORMAL WEATHER OVERSPREADS THE REGION THROUGH WEDNESDAY. AN OCEAN STORM MAY IMPACT SOUTHERN NEW ENGLAND THU/FRI...OR MAY HARMLESSLY DRIFT OUT TO SEA. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... 7 PM UPDATE... POST FRONTAL AIRMASS DRYING OUT LOW LEVELS OF THE ATMOSPHERE ACROSS THE REGION WITH DEW PTS FALLING INTO THE TEENS ACROSS CT...MUCH OF INTERIOR MA AND NEARBY NH. THIS IS RESULTING IN RELATIVELY HIGH CLOUD CEILINGS AROUND 9000FT OR SO WITH LOTS OF DRY AIR BELOW THE CLOUD BASE. THUS DILEMMA REMAINS HOW FAR NORTH WILL SNOW SHIELD PENETRATE DRY LOW LEVELS ACROSS THE REGION. CONTINUE TO THINK AREA OF HIGHEST RISK FOR ACCUMULATING SNOW WILL BE OVER CAPE COD AND THE ISLANDS WHERE INCREASING NNE WINDS OFF THE OCEAN WILL SATURATE LOW LEVELS TOWARD MORNING...YIELDING A DEEP COLUMN OF MOISTURE ACROSS THIS REGION. THEREFORE THIS AREA STANDS THE HIGHEST RISK FOR ACCUMULATING SNOW. RECENT 18Z NAM/GFS-15Z SREF AND RECENT HRRR RUNS SUGGEST STEADIER SNOWS EXIT THE OH VALLEY AT 00Z/7PM WILL ARRIVE ALONG THE IMMEDIATE SOUTH COAST/CAPE COD AND ISLANDS BETWEEN MIDNIGHT AND 09Z/4AM AND CONTINUE THROUGH 12Z/7AM BEFORE EXITING LATER IN THE MORNING. NORTH OF THE IMMEDIATE SOUTH COAST IT COULD BE A COMPLETE SHUTOUT WITH LITTLE IF ANY SNOWFALL. THUS HIGHEST FORECAST CONFIDENCE IS WHERE THE CURRENT WINTER WEATHER ADVISORY IS POSTED...CAPE COD AND THE ISLANDS. HOWEVER NEXT SHIFT WILL HAVE TO CLOSELY MONITOR HOW SNOW SHIELD EVOLVES...WHICH MAY BE MORE OFFSHORE THAN EARLIER THOUGHT...WHICH WOULD RESULT IN CANCELING THE WINTER WEATHER ADVISORY. WILL JUST HAVE TO WATCH THIS OVER THE NEXT FEW HOURS. EARLIER DISCUSSION BELOW. *** TIGHT SNOW GRADIENT EXPECTED BEGINNING TONIGHT *** VERY WEAK SFC COLD FRONT CURRENTLY JUST OFFSHORE OF THE ISLANDS AND CONTINUING A SLOW MARCH TO THE S. MSAS MASS FIELDS SHOWS THE WAVE OF LOW PRES ALREADY BEGINNING TO DEVELOP OVER VA/NC THIS AFTERNOON...PRETTY CLOSE TO WHERE MOST DETERMINISTIC GUIDANCE SUGGESTS. THE BULK OF PRECIP FROM THE FRONT ITSELF HAS SHIFTED OFFSHORE...AND REMAINED RELATIVELY LIGHT TODAY AS LIFT WAS VERY WEAK TO BEGIN WITH. THIS WAVE WILL BEGIN A SLOW MARCH TO THE NE DURING THE OVERNIGHT HOURS...WITH WRAP AROUND WARM CONVEYOR SIGNAL SPREADING N TO BRUSH THE COASTAL REGIONS OF SRN NEW ENGLAND BEGINNING ESPECIALLY BETWEEN 04-07Z. THE REAL ISSUE HERE IS HOW FAR N THIS BANDING GETS. NOTING A COMBINATION OF VERY CONFLUENT FLOW ALOFT...AS WELL AS RAPID DRYING OF THE LOW LVLS AS SFC DWPTS DIP DOWN INTO THE SINGLE DIGITS ACROSS SRN NH AND INTO MUCH OF INTERIOR MA BY 12Z. THEREFORE...EVEN IF RETURNS ON RADAR SPREAD FURTHER N OF THE CT/RI BORDER OVERNIGHT...DRY AIR IN THE LOWER REACHES OF THE COLUMN MAY LIMIT HOW MUCH ACTUALLY REACHES THE SFC. INDEED THE MODEL TREND CONTINUES TO LOWER LIQUID EQUIVALENTS AND SHIFT THE HEAVIER AXIS OFFSHORE. WITH ADJUSTMENTS TODAY...EVEN AREAS WITH CURRENT ADVISORIES ONLY JUST BREAK THE 3 INCH TOTAL MARK THANKS TO NEAR 15 TO 1 RATIOS /A LITTLE HIGHER ON ACK...MAYBE APPROACHING 4/. IF YOU NOTE A LACK OF OVERALL CONFIDENCE HERE IT/S BECAUSE WITH THE LIFT BEING SO WEAK AND OUT OF THE FAVORED -12C TO -18C SNOW GROWTH REGION AND OVERALL QPF VALUES...IT MAY BE THAT CURRENT ADVISORIES DON/T FULLY PAN OUT. HOWEVER ONLY A SLIGHT /LIKE 20-30 MILES/ N SHIFT IN THE OFFSHORE BANDING MAY MAKE A BIG DIFFERENCE HERE...SO WILL MAINTAIN THEM AS THEY STAND DUE TO HOW CLOSE IT MAY GET. IF MID CREW ASSESS BETTER BANDING REMAINS OFFSHORE...THEY MAY WISH TO DROP IT EARLY. THERE IS ONE ENHANCEMENT FEATURE TO NOTE...A SLIGHT N-NE WIND COMPONENT DRAWING IN THE COLDER AIR FROM NRN NEW ENGLAND MAY LEAD TO SOME OCEAN ENHANCEMENT...ESPECIALLY ACROSS THE PORTIONS OF THE S SHORE WHICH EXTENDS INTO MA BAY AND CAPE COD BAY...AS WELL AS THE CAPE ITSELF. NANTUCKET MAY HAVE ENOUGH DRAW OVER NANTUCKET SOUND FOR THIS AS WELL. DO NOTE A PERIOD WHERE SFC-H85 LAPSE RATES REACH NEAR DRY ADIABATIC LEVELS. THIS MAY HELP SNOW TOTALS A BIT ESPECIALLY IN THE PEAK 06-12Z TIMEFRAME. FURTHER N...LOOKING AT A VERY TIGHT GRADIENT BETWEEN THE HAVES AND HAVE NOT/S WITH THIS EVENT. AREAS ESPECIALLY N OF THE ROUTE-6 AND I-195 CORRIDORS /EXCEPT FOR E COASTAL MA DUE TO THE OCEAN ENHANCEMENT MENTIONED ABOVE/ MAY STRUGGLE AS THE DRY AIR ENTRAINS FURTHER S...CUTTING OFF THE MOISTURE AVAILABLE IN THE CORE OF WEAK LIFT ALOFT AND LEADING TO VIRGA. STILL A BIT OF LIGHT SNOW IS POSSIBLE UP TO THE MA PIKE BY THE TIMING OF THE MORNING COMMUTE...WHICH MAY LEAD TO A LOW END IMPACT...BUT OBSERVATION VS RADAR TRENDS WILL NEED TO BE WATCHED CLOSE THROUGH THE OVERNIGHT TO BETTER REFINE THE SNOW TOTALS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... A GRADUAL END TO THE SNOWS FOR SRN CT/RI AND SE MA IS EXPECTED THROUGH THE MORNING HOURS AS BOTH THE LOW PRES AND ATTENDANT FRONT PUSH FURTHER S AND E OF THE REGION...MOVING THE WARM CONVEYOR BELT FURTHER OFFSHORE. AS MENTIONED ABOVE...MAY NEED TO WATCH SOME AREAS FOR LIGHT SNOW DURING THE COMMUTE BUT THE BEST CHANCE IS THE ROUTE 6 FROM CT AND RI INTO THE I-195 CORRIDOR AND S SHORE OF MA. IN FACT...SOME AREAS OF SRN NH MAY ACTUALLY SEE THE SUNRISE...WHERE THE DRY/COLD AIRMASS HAS ALREADY MOVED IN. AFTER THE BULK OF THE SNOWFALL ENDS...A COLD AIRMASS WILL BEGIN MOVING SE OVER THE REGION THROUGH THE DAYLIGHT HOURS. H85 TEMPS MAY BE APPROACHING -14C BY 00Z. THEREFORE...EXPECT MAXES TO BE ON THE ORDER OF 10F COLDER THAN SUN. RANGING FROM HIGHS IN THE LOW TO UPPER 20S. WITH H85 TEMPS APPROACHING -14C AND SST NEAR +2C...MAY NEED TO WATCH ESPECIALLY THE OUTER CAPE COD FOR A PERIOD OF LATE DAY OCEAN EFFECT SNOW SHOWERS AND LOW CLOUDS. WIND TRAJECTORIES WILL BE SHIFTING FROM NEAR DUE N TO NW WITH TIME...SO JUST ENOUGH OF A COMPONENT TO SUPPORT A BRUSH AS THEY DEVELOP INTO THE OVERNIGHT HOURS. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... HIGHLIGHTS... * 15 TO 20 DEGS COLDER THAN NORMAL THROUGH WED * NOT AS COLD THU/FRI/SAT * WATCHING OCEAN STORM THU/FRI MONDAY NIGHT... COLD AIR ADVECTION ON NORTH-NORTHEAST WINDS WILL CONTINUE TO YIELD A RISK OF OCEAN EFFECT SNOW SHOWERS ACROSS EASTERN MA. SNOW SHOWERS SHOULD DIMINISH SECOND HALF OF THE NIGHT AS MID LEVEL FLOW TRANSITIONS FROM CYCLONIC TO ANTICYCLONIC. ELSEWHERE VERY COLD AND DRY WEATHER PREVAILS WITH WINDS DIMINISHING LATE. LOW TEMPS MON NIGHT WILL AVERAGE 15-20 DEGS COLDER THAN NORMAL. TUESDAY... VERY COLD START TO THE DAY. IN FACT NEAR RECORD COLD MINS MON NGT/TUE MORNING ACROSS THE INTERIOR. FOR EXAMPLE BDL/S RECORD MIN TUE MAR 4TH IS +2F IN 1950. OUR FORECAST MIN TUE MORNING FOR BDL IS +4F. ORH/BOS AND PVD APPEAR SAFE FROM BREAKING ANY RECORD LOWS. NONETHELESS A VERY COLD START TO THE DAY TUE. PGRAD RELAXES BY AFTN...THUS DIMINISHING WIND. HOWEVER HIGHS ONLY IN THE 20S WHICH ARE 15-20 DEGS COLDER THAN NORMAL FOR EARLY MARCH! TUESDAY NIGHT/WEDNESDAY NIGHT... ARCTIC FRONT APPROACHES FROM THE NORTH. BROAD WEST TO EAST CONFIGURATION OF ARCTIC HIGH ACROSS ONTARIO AND QUEBEC YIELDS A LONG MOIST EAST-NORTHEAST FETCH ACROSS GULF OF MAINE AND INTO SOUTHERN NEW ENGLAND. THIS MAY YIELD PERIODS OF VERY LIGHT SNOW OR FLURRIES ACROSS THE AREA. OTHERWISE COLD WEATHER CONTINUES. THURSDAY/FRIDAY... MODEL DIFFERENCES ON TIMING WITH NEXT SYSTEM. GFS AND ITS ENSEMBLES FASTER THAN THE ECMWF AND ITS ENSEMBLES. NEVERTHELESS ALL MODEL GUIDANCE AGREES THAT A POTENT AND MOIST SOUTHERN STREAM SYSTEM MOVES ACROSS THE GULF STATES THIS PERIOD. ALL GUIDANCE INCLUDING THE ENSEMBLES SUGGEST STREAMS WILL REMAIN SEPARATE YIELDING AN UNPHASED SOLUTION. THIS WOULD SUGGEST A NOT A BIG EVENT FOR NEW ENGLAND. WHILE THERE IS LARGE SPREAD AT THE SURFACE THE UPPER AIR PATTERN SUGGEST THE SOUTHERN STREAM SYSTEM MAY NOT REACH OUR LATITUDE WITH THE BULK OF THE MOISTURE/PRECIP REMAINING SOUTH OF NEW ENGLAND. IF THE NORTHERN PRECIP SHIELD DOES REACH OUR LATITUDE COLD AIR IS RETREATING NORTH-NORTHEAST BACK INTO CANADA DURING THIS TIME. THIS COMBINED WITH THE LACK OF COLD NORTHERN STREAM MERGER...ANY PRECIP THAT DOES REACH SOUTHERN NEW ENGLAND COULD BE PTYPE ISSUES AS PREVIOUS FORECASTER NOTED. SATURDAY/SUNDAY... LIKELY DRY BUT BOTH GFS AND ECMWF ENSEMBLES SUGGEST ANOTHER SURGE OF COLDER AIR INVADING NEW ENGLAND...ALTHOUGH NOT OF THE SAME MAGNITUDE OF PREVIOUS COLD AIR OUTBREAKS HERE. GEFS ANOMALIES SUGGEST 850 MB TEMPS DIPPING TO ABOUT -1 STANDARD DEVIATION COLDER THAN CLIMO. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH MONDAY/...HIGH CONFIDENCE IN GENERAL TRENDS...LOWER CONFIDENCE IN EXACT SNOW/NO SNOW LINE OVERNIGHT INTO TOMORROW. 7 PM UPDATE... TRENDED 00Z TAFS FARTHER SOUTH WITH LOWER CIGS AND VSBYS WHICH SHOULD BE CONFINED TO CAPE COD AND THE ISLANDS...POSSIBLY IMMEDIATE SOUTH COAST OF RI AND MA. STEADIER SNOWS ARRIVE AFTER 06Z AND CONTINUES THRU 12Z MON BEFORE TAPERING OFF BY 15Z. VFR DEVELOPING EVERYWHERE AFTER 15Z MON WITH N WINDS WITH GUSTS 15-20 KT AND VFR CONDITIONS. PRELIM ACCUMULATIONS... 2-4" KFMH/KHYA/KACK 0-1" KPVD 0-1" KBDL/KBOS LITTLE IF ANY SNOW KBAF/KORH/KBED/KMHT KBOS TERMINAL...HIGH CONFIDENCE IN TAF. IT IS POSSIBLE THAT LITTLE TO NO SNOW DEVELOPS FOR BOS. KBDL TERMINAL...HIGH CONFIDENCE IN TAF. IT IS POSSIBLE THAT ANY SNOW REMAINS ONLY A COATING WITH MOSTLY MVFR/VFR VSBYS. OUTLOOK...MONDAY NIGHT THROUGH FRIDAY... MON NIGHT...VFR EXCEPT LOW PROB OF MVFR IN SNOW SHOWERS EASTERN MA ALONG WITH GUSTY NNE WIND. MODERATE FORECAST CONFIDENCE. TUE...VFR WITH A DIMINISHING WIND. MODERATE FORECAST CONFIDENCE. TUE NIGHT THRU WED NIGHT...VFR HOWEVER PERIODS OF MVFR POSSIBLE IN VERY LIGHT SNOW OR FLURRIES. MODEST NE WIND WITH STRONGEST WIND EASTERN MA. MODERATE FORECAST CONFIDENCE. THU/FRI...LOW CONFIDENCE FORECAST AS OCEAN LOW APPROACHES FROM THE SOUTH AND ANOTHER LOW EXITS THE GREAT LAKES. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. TODAY THROUGH MONDAY...HIGH CONFIDENCE. MAINLY QUIET BOATING WEATHER EXPECTED THROUGH THE EVENING HOURS SAVE FOR SOME LIGHT RAIN CHANGING TO SNOW ESPECIALLY FOR THE SRN WATERS. AS LOW PRES PASSES WELL S OF THE COASTAL WATERS...N WINDS WILL BE INCREASING DURING THE EARLY MORNING HOURS SUCH THAT THEY GUST TO 25 KT ACROSS MOST OF THE OCEAN AND E INTRA-COASTAL WATERS THROUGH THE DAY MON. SEAS WILL GRADUALLY BUILD WITH TIME AS WELL...REACHING 5-6 FT ON THE OCEAN WATERS BY LATE MORNING AND AFTERNOON. THEREFORE...SMALL CRAFT ADVISORIES HAVE BEEN ISSUED. OUTLOOK...MONDAY NIGHT THROUGH FRIDAY... FORECAST CONFIDENCE MODERATE TO HIGH EXCEPT LOW THU/FRI. MONDAY NIGHT...MODEST NNE WIND. ARCTIC AIRMASS COMBINED WITH NNE WIND WILL LIKELY YIELD LIGHT TO MODERATE FREEZING SPRAY ESPECIALLY NORTHEAST MA WATERS. TUESDAY...WINDS DIMINISH. GOOD VSBY AND DRY WEATHER. TUE NIGHT THRU WED NIGHT...NE WINDS INCREASING AHEAD OF NEXT ARCTIC HIGH. VSBY REDUCED AT TIMES IN SNOW SHOWERS/FLURRIES. THU/FRI...OCEAN LOW APPROACHES FROM THE SOUTH...BUT MAY JUST DRIFT OUT TO SEA WITH LITTLE IMPACT. NEED TO WATCH THIS CLOSELY. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR MAZ022>024. NH...NONE. RI...WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR RIZ008. MARINE...SMALL CRAFT ADVISORY FROM 7 AM TO 4 PM EST MONDAY FOR ANZ231>234. SMALL CRAFT ADVISORY FROM 3 AM TO 7 PM EST MONDAY FOR ANZ250- 251-254>256. && $$ SYNOPSIS...NOCERA/DOODY NEAR TERM...NOCERA/DOODY SHORT TERM...DOODY LONG TERM...NOCERA AVIATION...NOCERA/DOODY MARINE...NOCERA/DOODY
AREA FORECAST DISCUSSION
NWS NEW YORK NY
708 PM EST SUN MAR 2 2014 .SYNOPSIS... WEAK WAVES OF LOW PRESSURE MOVE ALONG AN OFFSHORE COLD FRONT TONIGHT AND MONDAY. AT THE SAME TIME...HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. THIS ARCTIC HIGH PRESSURE SYSTEM MOVES EAST THROUGH TUESDAY NIGHT. A WEAK WAVE OF LOW PRESSURE PASSES THROUGH THE AREA WEDNESDAY INTO WEDNESDAY NIGHT. ARCTIC HIGH PRESSURE BUILDS TO THE NORTH THURSDAY AND MOVES OFF THE NORTHEAST COAST THURSDAY NIGHT. LOW PRESSURE MOVING OUT OF THE GULF OF MEXICO...AND PASSING SOUTH OF THE AREA...WILL AFFECT THE REGION THURSDAY NIGHT THROUGH FRIDAY NIGHT. && .NEAR TERM /THROUGH MONDAY/... AFTER THE INITIAL WAVE MOVING THROUGH THE REGION AT THIS TIME...THERE WILL BE A BREAK WITH LITTLE TO NO PRECIPITATION EXPECTED FOR SEVERAL HOURS...PROBABLY NOT UNTIL AFTER 06Z...WHEN THE PRECIPITATION BACK OVER THE OHIO VALLEY WITH THE SECOND WAVE MOVES INTO THE REGION. THE NAM AND HRRR PICKING UP ON THIS TREND ALSO. SO HAVE LOWERED POPS THROUGH THIS EVENING. IN CONJUNCTION WITH THE LOWER POPS HAVE LOWERED THE QPF AND SNOW TOTALS. THIS NOW GIVES JUST UNDER ADVISORY CRITERIA. HOWEVER WITH IMPACTS TO THE MORNING COMMUTE HAVE LET THE ADVISORY POSTED. A COLD FRONT REMAINS OFFSHORE WITH WEAK WAVES OF LOW PRESSURE RIDING NE ALONG THE FRONT. THERMAL PROFILES SUPPORT PCPN TYPE OF SNOW...BUT THERE IS STILL A CHANCE FOR SOME SLEET TO MIX IN VERY EARLY IN THE EVENING. FOR MOST THE NIGHT...LIFT IS NOT EXPECTED TO BE STRONG. IT`S NOT UNTIL LATE AT NIGHT WHERE SOME MID LEVEL LIFT DROPS DOWN FROM THE NORTH AND MID LEVEL FRONTOGENETIC SHIFTING IN FROM THE WEST COME INTO PLAY. SO EXPECTING A LIGHT TO MODERATE SNOWFALL TONIGHT. OVERALL LIFT INCREASES MONDAY MORNING...HOWEVER THE BEST SYNOPTIC LIFT WILL BE FARTHER TO OUR NORTH AS THE RIGHT REAR QUADRANT OF AN UPPER JET STREAK MOVES THROUGH. ADDITIONALLY...THE BEST MID LEVEL FRONTOGENETIC FORCING WILL BE JUST OFFSHORE. AT THE SAME TIME...HIGH PRESSURE BUILDING IN FROM THE NW SUPPRESSES MOISTURE FARTHER SOUTH AND EAST...WITH SNOW ENDING FROM NORTH TO SOUTH AS THE MORNING PROGRESSES. HAVE THEREFORE GONE WITH SNOW TO LIQUID RATIOS OF 11:1 FOR MOST OF THE EVENT. THERE IS A CHANCE OF SLIGHTLY HIGHER RATIOS BEING REALIZED ALONG THE SOUTHERNMOST ZONES DUE TO FRONTOGENETIC FORCING...BUT IT LOOKS LIKE THE BEST FORCING WILL BE JUST OFF TO THE SOUTH AND OCCURRING TOO LATE IN THE GAME. OMEGA IN THE SNOW GROWTH ZONE NEVER GETS TOO IMPRESSIVE EITHER. DRY WEATHER FOR MONDAY AFTERNOON WITH ANY LINGERING SNOW JUST OFFSHORE. CLOUDS WILL DIMINISH AS WELL. TEMPERATURES DURING THE EVENT WILL BE RUNNING BELOW NORMAL LEVELS...WITH HIGHS DURING MONDAY ABOUT 20 DEGREES BELOW NORMAL. NORTHERLY WINDS WILL PRODUCE WIND CHILL VALUES IN THE SINGLE DIGITS TO AROUND 10 DEGREES DURING THE DAY MONDAY. && .SHORT TERM /MONDAY NIGHT/... THE CENTER OF HIGH PRESSURE SHIFTS CLOSER TO THE AREA MONDAY NIGHT. DRY WEATHER WITH A MOSTLY CLEAR SKY. TEMPS WILL REMAIN ABNORMALLY COLD...WITH LOWS IN THE TEENS FOR THE CITY AND NEARBY AREAS OF LONG ISLAND. SINGLE DIGITS FOR MOST EVERYWHERE ELSE...AND EVEN SOME SPOTS BELOW ZERO OVER THE FAR NW PORTIONS OF THE AREA. WIND CHILL VALUES IN THE SINGLE DIGITS TO AROUND ZERO. && .LONG TERM /TUESDAY THROUGH SUNDAY/... TUESDAY INTO WEDNESDAY THERE ARE SOME DIFFERENCES WITH THE WEAK WAVE OF LOW PRESSURE MOVING THROUGH WEDNESDAY. THE GFS IS WEAKER AND KEEPS THE SURFACE LOW AND UPPER TROUGH TO THE NORTH OF THE REGION...WHILE THE NAM AND ECMWF MOVE THE LOW THROUGH. WITH PREVIOUS FORECASTS BRINGING THE LOW THROUGH HAVE LEANED TOWARD THAT SOLUTION FOR CONSISTENCY. COLD AIR WILL BE IN PLACE AND PRECIPITATION LIGHT...WITH MAINLY SLIGHT CHANCE POPS...SO HAVE SNOW SHOWERS WITH THE WAVE. ARCTIC HIGH PRESSURE BUILDS NORTH OF THE REGION...ACROSS THE GREAT LAKES...SHIFTING OFF THE COAST THURSDAY NIGHT INTO FRIDAY. MEANWHILE THE NORTHERN STREAM UPPER FLOW IS NEARLY ZONAL WITH THE SOUTHERN STREAM HAS A SHORTWAVE MOVING INTO THE SOUTHERN PLAINS WEDNESDAY AND AMPLIFYING. THE SHORTWAVE IS EXPECTED TO MOVE INTO THE GULF COAST STATES AND TRACK NORTHEAST. WITH THE HIGH REMAINING TO THE NORTH SOME UNCERTAINTY HOW FAR NORTH THE LOW WILL MOVE BELOW MOVING OFF SHORE SOUTH OF THE REGION. THE 12Z ECMWF IS NOW KEEPING THE PRECIPITATION JUST SOUTH OF THE AREA. AND MODEL UNCERTAINTIES REMAIN WITH THE GFS SHOWING THE MOST VARIABILITY AND NOT AS DEEP AND MORE PROGRESSIVE THAN THE ECMWF. AGAIN FOR CONSISTENCY HAVE LEANED TOWARD THE WPC GUIDANCE FOR THURSDAY NIGHT THROUGH SUNDAY WITH SOME BLEND OF THE ECMWF. TEMPERATURES REMAIN BELOW NORMAL THROUGH THE PERIOD WITH SOME MODERATION FRIDAY AND SATURDAY AS THE ARCTIC HIGHS MOVES EAST AND SOME WARMER AIR MOVES IN WITH THE LOW MOVING OFF THE SOUTHEAST COAST. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... WAVES OF LOW PRESSURE WILL MOVE ALONG THE FRONTAL BOUNDARY TO OUR SOUTH TONIGHT INTO MONDAY. MADE PRETTY SIGNIFICANT CHANGES TO THE TAFS JUST BEFORE THE 00Z ISSUANCE. ONE AREA OF LIGHT PCPN HAS EXITED NYC TERMINALS AND LATEST RADAR AND MODEL GUIDANCE INDICATES THAT WE SHOULD REMAIN VFR AND DRY UNTIL AROUND 07-08Z. AT THAT POINT...THE NORTHERN EDGE OF THE PCPN SHIELD IS EXPECTED TO MOVE INTO NYC TERMINALS AND EXPAND EASTWARD. THERMAL PROFILES INDICATE SNOW FOR THE SHORT DURATION OF 3-6 HOURS THAT IT IS OVER THE TERMINALS. GUIDANCE CONTINUES TO CUT BACK ON THE NORTHERN EXTENT OF THE PCPN SHIELD WITH HIGHEST AMOUNTS LIKELY AT KEWR/KJFK WHERE AROUND 2 INCHES IS EXPECTED. AMOUNTS AT KSWF WILL LIKELY BE LESS THAN AN INCH. TIMING MAY BE OFF 1-2 HOURS...BUT HAVE MODERATE CONFIDENCE IN FORECAST. GUSTS PICK UP LATE AND MAY BE HOLDING ON TO THEM A FEW HOURS TOO LONG MON AFTN. .OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY... .MON NIGHT-TUE...VFR. .TUE NIGHT...MAINLY VFR. .WED...POTENTIAL FOR MVFR/IFR IN -SHSN. .WED NIGHT-THU...VFR LIKELY. .THU NIGHT-FRI...CHANCE OF RAIN/SNOW. MVFR OR LOWER POSSIBLE. && .MARINE... WINDS WILL PICK UP DURING THE LATE NIGHT HOURS AS HIGH PRESSURE BUILDS IN FROM THE WEST...CREATING A TIGHTER PRESSURE GRADIENT OVER THE AREA WATERS AS WAVES OF LOW PRESSURE RIDE ALONG A COLD FRONT TO THE SOUTH. SCA-LEVEL WINDS SHOULD COMMENCE OVERNIGHT ON THE OCEAN WATERS AND LAST INTO A GOOD PORTION OF MONDAY AFTERNOON. ELSEWHERE...MARGINAL SCA-LEVEL GUSTS AND NOT ENOUGH CONFIDENCE FOR A LONG ENOUGH AND WIDESPREAD ENOUGH ADVISORY EVENT. HAVE THEREFORE LEFT THE NON-OCEAN WATERS OUT OF THE SCA. HAVE EXTENDED THE SCA THROUGH MONDAY AFTERNOON FOR THE OCEAN WATERS. WINDS AND SEAS DIMINISH EVERYWHERE MONDAY NIGH AS THE CENTER OF HIGH PRESSURE GETS CLOSER TO THE REGION. WINDS AND WAVES ARE FORECAST TO REMAIN BELOW SMALL CRAFT LEVELS TUESDAY THROUGH FRIDAY AS MAINLY HIGH PRESSURE REMAINS OVER THE FORECAST WATERS. A WEAK WAVE OF LOW PRESSURE PASSING THROUGH THE REGION WEDNESDAY INTO WEDNESDAY NIGHT MAY BRIEFLY PRODUCE SMALL CRAFT GUSTS ON THE OCEAN WATERS WEDNESDAY NIGHT. WITH HIGH PRESSURE TO THE NORTH FRIDAY INTO FRIDAY NIGHT AND A STORM SYSTEM APPROACHING FROM THE SOUTH WILL RESULT IN AN INCREASING NORTHEAST FLOW ACROSS THE WATERS. BY FRIDAY NIGHT GUSTS ON THE OCEAN WATERS AND POSSIBLY THE EASTERN SOUND AND BAYS MAY BE AROUND SMALL CRAFT...AND SEAS ON THE OCEAN WATERS ALSO MAY BE AROUND 5 FT. && .HYDROLOGY... WITH REGARD TO LIQUID EQUIVALENT...GENERALLY EXPECT JUST UNDER ONE TENTH AND UP TO TWO TENTHS OF AN INCH...WITH THE HIGHEST VALUES ACROSS LONG ISLAND...NYC...AND ADJACENT PARTS OF NJ. SINCE ALMOST ALL OF THE OF THE PRECIPITATION WILL BE IN THE FORM OF SNOW...NO HYDROLOGIC IMPACTS ARE EXPECTED. SIGNIFICANT PRECIPITATION IS NOT EXPECTED TUESDAY THROUGH SUNDAY. && .EQUIPMENT... THE NOAA WEATHER RADIO TRANSMITTER THAT SERVES THE NEW YORK CITY METROPOLITAN AREA REMAINS OUT OF SERVICE DUE TO RADIO FREQUENCY INTERFERENCE WITH THE U.S COAST GUARD TRANSMITTER. FOR MORE INFORMATION SEE THE FOLLOWING PUBLIC INFORMATION STATEMENT (ALL LOWER CASE): WWW.ERH.NOAA.GOV/OKX/PRODUCTS/STATIC.TXT && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR NYZ072>075- 078>081-176>179. NJ...WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR NJZ006- 105>108. MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 6 PM EST MONDAY FOR ANZ350- 353-355. && $$
AREA FORECAST DISCUSSION
NWS NEW YORK NY
605 PM EST SUN MAR 2 2014 .SYNOPSIS... WEAK WAVES OF LOW PRESSURE MOVE ALONG AN OFFSHORE COLD FRONT TONIGHT AND MONDAY. AT THE SAME TIME...HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. THIS ARCTIC HIGH PRESSURE SYSTEM MOVES EAST THROUGH TUESDAY NIGHT. A WEAK WAVE OF LOW PRESSURE PASSES THROUGH THE AREA WEDNESDAY INTO WEDNESDAY NIGHT. ARCTIC HIGH PRESSURE BUILDS TO THE NORTH THURSDAY AND MOVES OFF THE NORTHEAST COAST THURSDAY NIGHT. LOW PRESSURE MOVING OUT OF THE GULF OF MEXICO...AND PASSING SOUTH OF THE AREA...WILL AFFECT THE REGION THURSDAY NIGHT THROUGH FRIDAY NIGHT. && .NEAR TERM /THROUGH MONDAY/... AFTER THE INITIAL WAVE MOVING THROUGH THE REGION AT THIS TIME...THERE WILL BE A BREAK WITH LITTLE TO NO PRECIPITATION EXPECTED FOR SEVERAL HOURS...PROBABLY NOT UNTIL AFTER 06Z...WHEN THE PRECIPITATION BACK OVER THE OHIO VALLEY WITH THE SECOND WAVE MOVES INTO THE REGION. THE NAM AND HRRR PICKING UP ON THIS TREND ALSO. SO HAVE LOWERED POPS THROUGH THIS EVENING. IN CONJUNCTION WITH THE LOWER POPS HAVE LOWERED THE QPF AND SNOW TOTALS. THIS NOW GIVES JUST UNDER ADVISORY CRITERIA. HOWEVER WITH IMPACTS TO THE MORNING COMMUTE HAVE LET THE ADVISORY POSTED. A COLD FRONT REMAINS OFFSHORE WITH WEAK WAVES OF LOW PRESSURE RIDING NE ALONG THE FRONT. THERMAL PROFILES SUPPORT PCPN TYPE OF SNOW...BUT THERE IS STILL A CHANCE FOR SOME SLEET TO MIX IN VERY EARLY IN THE EVENING. FOR MOST THE NIGHT...LIFT IS NOT EXPECTED TO BE STRONG. IT`S NOT UNTIL LATE AT NIGHT WHERE SOME MID LEVEL LIFT DROPS DOWN FROM THE NORTH AND MID LEVEL FRONTOGENETIC SHIFTING IN FROM THE WEST COME INTO PLAY. SO EXPECTING A LIGHT TO MODERATE SNOWFALL TONIGHT. OVERALL LIFT INCREASES MONDAY MORNING...HOWEVER THE BEST SYNOPTIC LIFT WILL BE FARTHER TO OUR NORTH AS THE RIGHT REAR QUADRANT OF AN UPPER JET STREAK MOVES THROUGH. ADDITIONALLY...THE BEST MID LEVEL FRONTOGENETIC FORCING WILL BE JUST OFFSHORE. AT THE SAME TIME...HIGH PRESSURE BUILDING IN FROM THE NW SUPPRESSES MOISTURE FARTHER SOUTH AND EAST...WITH SNOW ENDING FROM NORTH TO SOUTH AS THE MORNING PROGRESSES. HAVE THEREFORE GONE WITH SNOW TO LIQUID RATIOS OF 11:1 FOR MOST OF THE EVENT. THERE IS A CHANCE OF SLIGHTLY HIGHER RATIOS BEING REALIZED ALONG THE SOUTHERNMOST ZONES DUE TO FRONTOGENETIC FORCING...BUT IT LOOKS LIKE THE BEST FORCING WILL BE JUST OFF TO THE SOUTH AND OCCURRING TOO LATE IN THE GAME. OMEGA IN THE SNOW GROWTH ZONE NEVER GETS TOO IMPRESSIVE EITHER. DRY WEATHER FOR MONDAY AFTERNOON WITH ANY LINGERING SNOW JUST OFFSHORE. CLOUDS WILL DIMINISH AS WELL. TEMPERATURES DURING THE EVENT WILL BE RUNNING BELOW NORMAL LEVELS...WITH HIGHS DURING MONDAY ABOUT 20 DEGREES BELOW NORMAL. NORTHERLY WINDS WILL PRODUCE WIND CHILL VALUES IN THE SINGLE DIGITS TO AROUND 10 DEGREES DURING THE DAY MONDAY. && .SHORT TERM /MONDAY NIGHT/... THE CENTER OF HIGH PRESSURE SHIFTS CLOSER TO THE AREA MONDAY NIGHT. DRY WEATHER WITH A MOSTLY CLEAR SKY. TEMPS WILL REMAIN ABNORMALLY COLD...WITH LOWS IN THE TEENS FOR THE CITY AND NEARBY AREAS OF LONG ISLAND. SINGLE DIGITS FOR MOST EVERYWHERE ELSE...AND EVEN SOME SPOTS BELOW ZERO OVER THE FAR NW PORTIONS OF THE AREA. WIND CHILL VALUES IN THE SINGLE DIGITS TO AROUND ZERO. && .LONG TERM /TUESDAY THROUGH SUNDAY/... TUESDAY INTO WEDNESDAY THERE ARE SOME DIFFERENCES WITH THE WEAK WAVE OF LOW PRESSURE MOVING THROUGH WEDNESDAY. THE GFS IS WEAKER AND KEEPS THE SURFACE LOW AND UPPER TROUGH TO THE NORTH OF THE REGION...WHILE THE NAM AND ECMWF MOVE THE LOW THROUGH. WITH PREVIOUS FORECASTS BRINGING THE LOW THROUGH HAVE LEANED TOWARD THAT SOLUTION FOR CONSISTENCY. COLD AIR WILL BE IN PLACE AND PRECIPITATION LIGHT...WITH MAINLY SLIGHT CHANCE POPS...SO HAVE SNOW SHOWERS WITH THE WAVE. ARCTIC HIGH PRESSURE BUILDS NORTH OF THE REGION...ACROSS THE GREAT LAKES...SHIFTING OFF THE COAST THURSDAY NIGHT INTO FRIDAY. MEANWHILE THE NORTHERN STREAM UPPER FLOW IS NEARLY ZONAL WITH THE SOUTHERN STREAM HAS A SHORTWAVE MOVING INTO THE SOUTHERN PLAINS WEDNESDAY AND AMPLIFYING. THE SHORTWAVE IS EXPECTED TO MOVE INTO THE GULF COAST STATES AND TRACK NORTHEAST. WITH THE HIGH REMAINING TO THE NORTH SOME UNCERTAINTY HOW FAR NORTH THE LOW WILL MOVE BELOW MOVING OFF SHORE SOUTH OF THE REGION. THE 12Z ECMWF IS NOW KEEPING THE PRECIPITATION JUST SOUTH OF THE AREA. AND MODEL UNCERTAINTIES REMAIN WITH THE GFS SHOWING THE MOST VARIABILITY AND NOT AS DEEP AND MORE PROGRESSIVE THAN THE ECMWF. AGAIN FOR CONSISTENCY HAVE LEANED TOWARD THE WPC GUIDANCE FOR THURSDAY NIGHT THROUGH SUNDAY WITH SOME BLEND OF THE ECMWF. TEMPERATURES REMAIN BELOW NORMAL THROUGH THE PERIOD WITH SOME MODERATION FRIDAY AND SATURDAY AS THE ARCTIC HIGHS MOVES EAST AND SOME WARMER AIR MOVES IN WITH THE LOW MOVING OFF THE SOUTHEAST COAST. && .AVIATION /21Z MONDAY THROUGH FRIDAY/... WAVES OF LOW PRESSURE WILL MOVE ALONG THE FRONTAL BOUNDARY TO OUR SOUTH TONIGHT INTO MONDAY. NW-NNW WINDS LESS THAN 10 KT INCREASE LATE TONIGHT INTO MONDAY WITH SUSTAINED SPEED AROUND 12-15 KT AND GUSTS TO AROUND 20 KT. VFR TRANSITIONS TO MVFR THIS EVENING...EVENTUALLY DETERIORATING TO IFR LATE WITH GRADUAL IMPROVEMENT MONDAY MORNING AND AFTERNOON. EXCEPTION WILL BE KSWF WHICH WILL LOWER ONLY TO MVFR. OCCASIONAL PRECIPITATION OVER THE NEXT FEW HOURS WILL BE A MIX OF SNOW/RAIN/SLEET TOWARDS THE COAST BEFORE BECOMING STEADY SNOW TONIGHT. SNOW COULD OCCASIONALLY BE HEAVIER BUT THINK THAT IFR WILL BE LOWER LIMIT OF CONDITIONS. CATEGORICAL CHANGES OF 1-3 HRS WILL BE POSSIBLE WITH LATER FORECASTS DUE TO UNCERTAINTY SO AMENDMENTS WILL BE POSSIBLE. SNOWFALL ACCUMULATIONS FORECAST...NYC AND LONG ISLAND TERMINALS...AROUND 2-3 INCHES AND GENERALLY AROUND 1.5 INCHES OR LESS TO THE NORTH WITH THE BULK OF IT FALLING LATE TONIGHT INTO EARLY MONDAY. .OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY... .MON...VFR. N-NW GUSTS 20-25 KT. .MON NIGHT-TUE...VFR. .TUE NIGHT...MAINLY VFR. .WED...POTENTIAL FOR MVFR/IFR IN -SHSN. .WED NIGHT-THU...VFR LIKELY. .THU NIGHT-FRI...CHANCE OF RAIN/SNOW. MVFR OR LOWER POSSIBLE. && .MARINE... WINDS WILL PICK UP DURING THE LATE NIGHT HOURS AS HIGH PRESSURE BUILDS IN FROM THE WEST...CREATING A TIGHTER PRESSURE GRADIENT OVER THE AREA WATERS AS WAVES OF LOW PRESSURE RIDE ALONG A COLD FRONT TO THE SOUTH. SCA-LEVEL WINDS SHOULD COMMENCE OVERNIGHT ON THE OCEAN WATERS AND LAST INTO A GOOD PORTION OF MONDAY AFTERNOON. ELSEWHERE...MARGINAL SCA-LEVEL GUSTS AND NOT ENOUGH CONFIDENCE FOR A LONG ENOUGH AND WIDESPREAD ENOUGH ADVISORY EVENT. HAVE THEREFORE LEFT THE NON-OCEAN WATERS OUT OF THE SCA. HAVE EXTENDED THE SCA THROUGH MONDAY AFTERNOON FOR THE OCEAN WATERS. WINDS AND SEAS DIMINISH EVERYWHERE MONDAY NIGH AS THE CENTER OF HIGH PRESSURE GETS CLOSER TO THE REGION. WINDS AND WAVES ARE FORECAST TO REMAIN BELOW SMALL CRAFT LEVELS TUESDAY THROUGH FRIDAY AS MAINLY HIGH PRESSURE REMAINS OVER THE FORECAST WATERS. A WEAK WAVE OF LOW PRESSURE PASSING THROUGH THE REGION WEDNESDAY INTO WEDNESDAY NIGHT MAY BRIEFLY PRODUCE SMALL CRAFT GUSTS ON THE OCEAN WATERS WEDNESDAY NIGHT. WITH HIGH PRESSURE TO THE NORTH FRIDAY INTO FRIDAY NIGHT AND A STORM SYSTEM APPROACHING FROM THE SOUTH WILL RESULT IN AN INCREASING NORTHEAST FLOW ACROSS THE WATERS. BY FRIDAY NIGHT GUSTS ON THE OCEAN WATERS AND POSSIBLY THE EASTERN SOUND AND BAYS MAY BE AROUND SMALL CRAFT...AND SEAS ON THE OCEAN WATERS ALSO MAY BE AROUND 5 FT. && .HYDROLOGY... WITH REGARD TO LIQUID EQUIVALENT...GENERALLY EXPECT JUST UNDER ONE TENTH AND UP TO TWO TENTHS OF AN INCH...WITH THE HIGHEST VALUES ACROSS LONG ISLAND...NYC...AND ADJACENT PARTS OF NJ. SINCE ALMOST ALL OF THE OF THE PRECIPITATION WILL BE IN THE FORM OF SNOW...NO HYDROLOGIC IMPACTS ARE EXPECTED. SIGNIFICANT PRECIPITATION IS NOT EXPECTED TUESDAY THROUGH SUNDAY. && .EQUIPMENT... THE NOAA WEATHER RADIO TRANSMITTER THAT SERVES THE NEW YORK CITY METROPOLITAN AREA REMAINS OUT OF SERVICE DUE TO RADIO FREQUENCY INTERFERENCE WITH THE U.S COAST GUARD TRANSMITTER. FOR MORE INFORMATION SEE THE FOLLOWING PUBLIC INFORMATION STATEMENT (ALL LOWER CASE): WWW.ERH.NOAA.GOV/OKX/PRODUCTS/STATIC.TXT && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR NYZ072>075- 078>081-176>179. NJ...WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR NJZ006- 105>108. MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 6 PM EST MONDAY FOR ANZ350- 353-355. && $$
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
938 PM EST SUN MAR 2 2014 ...PATCHY TO AREAS OF FOG INLAND TONIGHT... .UPDATE... SURFACE HIGH PRESSURE WILL BUILD FARTHER ESE FROM THE FL ATLANTIC COAST TONIGHT WITH LOW LEVEL WINDS VEERING SSW. THE FOG BANK THAT WAS ALONG THE ATLANTIC COAST COMPLETELY ERODED THIS EVENING...BUT IT REMAINS PROBABLE THAT PATCHY FOG DEVELOPMENT WILL BEGIN OVER THE NEXT COUPLE OF HOURS NEAR THE ATLANTIC COAST AND ST JOHNS RIVER BASIN AS DEW PT DEPRESSIONS FALL INTO THE 1-2 DEG RANGE WITH TEMPS IN THE MID/UPPER 50S. FARTHER INLAND...TEMPS STILL NEED TO COOL BY ABOUT 5-8 DEG OVER INLAND SE GA AND INLAND NE FL BEFORE SATURATION BEGINS. THE LOW STRATUS SOUTH OF APALACHEE BAY CONTINUED TO PERSIST...BUT RECENTLY BECAME MORE FRAGMENTED. THE SHORT RANGE MODEL GUIDANCE INCLUDING THE HRRR (RAPID REFRESH) AND NARRE CONTINUED TO HINT AT LOW STRATUS FORMING OVER THE FL PANHANDLE AND DRIFTING NNE TOWARD OUR SUWANNEE RIVER VALLEY ZONES AND INLAND SE GA ZONES AFTER MIDNIGHT. ADVERTISED PATCHY FOG OVER OUR GA ZONES WHERE SW BOUNDARY LAYER WINDS WILL PROGRESSIVELY INCREASE FROM THE SSW TO 20-25 KTS THROUGH THE NIGHT WHILE BETTER CHANCES FOR SOME DENSE FOG WILL REMAIN OVER INLAND NE FL AFTER MIDNIGHT CLOSER TO MEAN LAYER SUBSIDENCE. TEMPS WERE ON TRACK TO FALL TO MINS IN THE UPPER 40S/LOW 50S INLAND TO MID/UPPER 50S COAST. && .AVIATION...WINDS RIGHT ABOVE THE SURFACE ARE NOW FROM THE SW AND WILL INCREASE TONIGHT. EXPECT STRATUS TO SPREAD NE FROM THE GULF REACHING TAF LOCATIONS LATE TONIGHT AS RAPID REFRESH ENSEMBLE INDICATES. BEST CHANCE OF DENSE FOG/LOW CIGS WILL BE AT GNV WITH LIGHT FOG/LOW CIGS MORE LIKELY FURTHER EAST TOWARDS MORNING. WILL GO WITH IFR/LIFR AT GNV 06Z-13Z...AND AT JAX...CRG...VQQ...AND SSI 09Z-14Z. && .MARINE... VARIABLE WINDS 10 KTS OR LESS THIS EVENING WITH COMBINED SEAS OF 2-4 FT WITH THE HIGH PRESSURE RIDGE AXIS OVER THE LOCAL WATERS. AS THE NIGHT PROGRESSES...THE RIDGE AXIS WILL SHIFT SSE OVER S FL AND PULL FARTHER OFFSHORE OF THE ATLANTIC SEABOARD...WITH LOCAL SURFACE WINDS VEERING SSW AND INCREASING TO NEAR 10-15 KTS NEARSHORE TO 15 KTS OFFSHORE. MAIN CHANGE TO THE MARINE FORECAST WAS TO IMPROVE FOG WORDING ALONG THE COAST RIP CURRENTS: LOW RISK OF RIPS EXPECTED ON MONDAY. && .PRELIMINARY POINT TEMPS/POPS... AMG 50 75 42 54 / 0 50 20 30 SSI 56 77 48 56 / 0 30 30 30 JAX 52 81 50 61 / 0 30 30 30 SGJ 56 80 56 60 / 0 20 20 20 GNV 51 79 53 69 / 0 20 20 20 OCF 54 81 57 73 / 0 10 20 20 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ ENYEDI/ZIBURA/MCALLISTER
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
936 PM EST SUN MAR 2 2014 .SYNOPSIS... WELL BELOW NORMAL TEMPERATURES TONIGHT WITH SOUTHERLY FLOW AHEAD OF AN ARCTIC FRONT. THE COLD FRONT WILL CROSS THE REGION MONDAY AFTERNOON BRINGING LIGHT RAIN SHOWERS TO THE AREA. DRY BUT COLDER WEATHER EXPECTED FROM TUESDAY THROUGH WEDNESDAY AS ARCTIC AIR SETTLES INTO THE REGION. ANOTHER STRONGER SYSTEM WILL IMPACT THE REGION WEDNESDAY NIGHT THROUGH FRIDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... AN ARCTIC COLD FRONT CONTINUES TO EXPAND EASTWARD ACROSS THE NATION WHERE TEMPERATURES AT THE CENTER OF THE SURFACE HIGH ARE WELL BELOW ZERO OVER THE DAKOTAS AND NEBRASKA AND IOWA. EARLIER THIS EVENING AT 23Z TEXAS HAD A TEMPERATURE RANGE FROM 92 DEGREES IN THE SOUTHERN PART OF THE STATE TO 8 DEGREES IN THE PANHANDLE! THIS ARCTIC FRONT WILL BE SLOW TO CROSS THE MOUNTAINS OVERNIGHT BUT WILL EVENTUALLY MAKE IT OVER AND SPILL DOWN TOWARDS THE FORECAST AREA BY TOMORROW MORNING. SOUTHERLY FLOW AHEAD OF THE FRONT TONIGHT WILL HELP KEEP THE BOUNDARY LAYER MIXED AND LEAD TO WELL ABOVE NORMAL TEMPERATURES WITH LOWS IN THE LOWER 50S. CLOUDS WILL BE INCREASING LATE TONIGHT AS THE FRONT AND UPPER SYSTEM APPROACH. && .SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... MONDAY AND MONDAY NIGHT...LOW PRESSURE AND ASSOCIATED COLD FRONT WILL BEGIN THE DAY JUST WEST OF THE FORECAST AREA. THE COLD FRONT WILL RAPIDLY MOVE EASTWARD INTO THE WESTERN MIDLANDS BY EARLY AFTERNOON THEN THROUGH THE EASTERN MIDLANDS DURING THE MID AFTERNOON HOURS. TEMPERATURES WILL BE THE MAIN ISSUE THROUGH THE DAY AS STRONG COLD AIR ADVECTION WILL ACCOMPANY THE FRONT. TEMPERATURES WILL REACH DAYTIME HIGHS AROUND MIDDAY IN THE NORTHERN AND WESTERN MIDLANDS AND EARLY AFTERNOON IN THE EASTERN MIDLANDS. TEMPERATURES BEHIND THE FRONT WILL BEGIN TO QUICKLY FALL WITH LOWER 40S ENTERING THE NORTHERN MIDLANDS BY EARLY EVENING. MOISTURE WITH THE FRONT WILL BE MOVING EASTWARD AS THE COLD AIR ENTERS THE FORECAST AREA...HOWEVER POTENTIAL FOR SOME SLEET REMAINS ACROSS PRIMARILY LANCASTER AND CHESTERFIELD COUNTIES. AS SUCH HAVE REMAINED WITH CHANCE RAIN SHOWERS AND A SLIGHT CHANCE OF SLEET MIXED IN FOR LANCASTER AND CHESTERFIELD. WITH THE SHORT TIME FROM OF AVAILABLE MOISTURE AND WARM GROUND TEMPERATURES DO NOT EXPECT ANY ACCUMULATION. TEMPERATURES MONDAY NIGHT WILL CONTINUE FALLING AS STRONG COLD AIR ADVECTION OVERTAKES THE REGION WITH LOWS IN THE LOWER 20S ALONG THE NC LINE AND LOWER 30S IN THE CSRA. TUESDAY AND TUESDAY NIGHT...COLD FRONT WILL MOVE WELL OFFSHORE BY TUESDAY MORNING WITH A WEAK RIDGE OVER THE AREA. CLOUDS WILL INCREASE THROUGH THE DAY AS AN UPPER LEVEL DISTURBANCE IN THE WESTERN GULF OF MEXICO PUSHES MOISTURE NORTHWARD. COLD AIR ADVECTION REMAINING BEHIND THE COLD FRONT WILL KEEP TEMPERATURES WELL BELOW NORMAL THROUGH THE DAY WITH DAYTIME HIGHS RANGING FROM THE MID 40S IN THE NORTHERN MIDLANDS TO AROUND 50 IN THE CSRA. LOWS TUESDAY NIGHT WILL BE IN THE UPPER 20S TO LOWER 30S. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... UPPER LEVEL PATTERN WILL REMAIN MODERATELY AMPLIFIED THROUGH THE LONG TERM WITH AMPLIFICATION OVER THE SOUTHEAST FROM WEDNESDAY NIGHT ONWARD. MODELS ARE IN GOOD AGREEMENT SYNOPTICALLY WITH DIFFERENCES IN TIMING AND INTENSITY THROUGH THE LONG TERM...ESPECIALLY REGARDING THE LOW CROSSING THE REGION WEDNESDAY NIGHT THROUGH FRIDAY. UPPER LEVEL TROUGH WILL BEGIN DEEPENING OVER THE SOUTHERN PLAINS WEDNESDAY AFTERNOON WITH A WEAK LOW DEVELOPING IN THE WESTERN GULF STATES WEDNESDAY NIGHT. THE LOW WILL CONTINUE TRACKING EASTWARD REACHING THE FL PANHANDLE BY THURSDAY AFTERNOON. MODEL SOLUTIONS DIVERGE FOR THURSDAY NIGHT ONWARD AS CURRENTLY THE GFS TRACKS THE LOW RAPIDLY NORTHWARD ALONG THE COAST AND OFFSHORE OF NEW ENGLAND BY FRIDAY MORNING...WHILE THE ECMWF MOVES THE LOW MUCH SLOWER KEEPING IT OFFSHORE OF THE CAROLINAS FRIDAY MORNING. HAVE REMAINED CONSERVATIVE AND MADE FEW CHANGES TO THE FORECAST FOR THURSDAY NIGHT ONWARD DUE TO SIGNIFICANT RUN TO RUN MODEL CHANGES OVER THE PAST COUPLE OF RUNS KEEPING CONFIDENCE LOW. MODELS AGREE WEAK HIGH PRESSURE WILL BUILD IN TO THE REGION FRIDAY NIGHT THROUGH SATURDAY WITH THE NEXT SYSTEM APPROACHING ON SUNDAY. TEMPERATURES THROUGH THE LONG TERM WILL BE BELOW NORMAL. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... A SOUTHWEST FLOW WILL OCCUR BETWEEN HIGH PRESSURE OFF THE SOUTHEAST COAST AND THE APPROACHING STRONG COLD FRONT. EXPECT FRONTAL PASSAGE DURING THE 19Z TO 22Z TIME FRAME. MOISTURE WILL BE ON THE INCREASE AHEAD OF THE FRONT. THE NAM AND GFS MOS PLUS SREF GUIDANCE MAINTAIN VFR CONDITIONS THROUGH THE MORNING. HOWEVER...THE 23Z HRRR SHOWED AN IFR CEILING SPREADING INTO THE AREA FROM THE SOUTHWEST IN AN ISENTROPIC LIFT PATTERN. WE LEANED TOWARD THE MAV AND MET MOS AND MAINTAINED VFR CONDITIONS BUT CONFIDENCE IS NOT HIGH BECAUSE OF THE INCONSISTENT HRRR GUIDANCE. MIXING SHOULD HELP PREVENT FOG DURING THE EARLY MORNING HOURS. THE LATEST KCAE 88D VAD WIND PROFILE INDICATED SIGNIFICANT LOW-LEVEL WIND SHEAR. THE NAM INDICATED SIGNIFICANT WIND SHEAR SHOULD CONTINUE UNTIL AROUND 14Z WHEN HEATING AND MIXING SHOULD BECOME MORE DOMINATE. LATER IN THE DAY...THE NAM AND GFS MOS DIFFERED WITH THE NAM SHOWING IFR CEILINGS DEVELOPING JUST BEHIND THE FRONT. THE GFS MOS INDICATED LOW-END VFR OR MVFR CEILINGS. WE AVERAGED THIS GUIDANCE AND FORECASTED MVFR CEILINGS. THE NAM MOS MAY BE TOO LOW WITH ITS CEILING FORECAST BECAUSE CONSIDERABLE WIND SHOULD HELP HOLD UP CEILINGS. THERE MAY ALSO BE RESTRICTIONS ASSOCIATED WITH RAIN NEAR AND BEHIND THE FRONT BUT BELIEVE THIS RAIN WILL BE MAINLY LIGHT WITH LIMITED EFFECT ON VISIBILITY. WINDS WILL BE ESPECIALLY GUSTY AHEAD OF THE FRONT DURING THE DAY MONDAY. THE GFS LAMP INDICATED GUSTS OF 15 TO 20 KNOTS. THE NAM MOMENTUM TRANSFER TOOL SUPPORTED GUSTS NEAR 25 KNOTS. THE NAM AND GFS MOS AND THE LOSS OF HEATING AND MIXING SUPPORT MORE CONSISTENT NORTH WINDS AROUND 15 KNOTS BEHIND THE FRONT. EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS MAY LINGER DURING THE REST OF MONDAY NIGHT. LOW PRESSURE TRACKING NORTHEASTWARD ALONG THE SOUTHEAST COAST MAY RESULT IN WIDESPREAD MVFR OR IFR CONDITIONS WEDNESDAY NIGHT THROUGH FRIDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
903 PM CST SUN MAR 2 2014 .DISCUSSION... 258 PM CST THE PRIMARY FOCUS IN THE FORECAST WAS ON THE DEGREE OF THE COLD THE NEXT 24 HOURS...AT RECORD LEVELS IN SOME PLACES...AND THEN SNOW CHANCES THIS FIRST WEEK OF METEOROLOGICAL "SPRING". TONIGHT... THE LOCAL AREA FINDS ITSELF SQUEEZED BETWEEN A VERY DEEP UPPER LOW ACROSS HUDSON BAY AND A WELL-DEFINED CLOSED LOW ACROSS THE SOUTHERN PLAINS. THIS SOUTHERN SYSTEM IS PROGRESSING DUE EAST AND CREATING WIDESPREAD SNOW AND ICE TO OUR SOUTH. THIS FEATURE ALSO WILL CONTINUE HIGH CLOUDS ACROSS THE FORECAST AREA THIS EVE WITH SOUTHWEST FLOW ABOVE 15K FT. BUT ASIDE FROM THAT...THE CONFLUENCE ALOFT OVER THE SURFACE HIGH PRESSURE RIDGE WILL KEEP CONDITIONS TRANQUIL. THE LAKE EFFECT SNOW SHOWERS FROM EARLIER TODAY HAVE DIMINISHED IN INTENSITY WITH LESS CONVERGENCE AND JUST DEEPER DRY AIR ADVECTION. WHILE SOME LIGHT SHOWERS ARE ANTICIPATED AT TIMES TONIGHT AND EVEN MONDAY MORNING INTO FAR NORTHWEST INDIANA...ANY ADDITIONAL ACCUMULATION LOOKS TO BE PRETTY LIGHT. WITH THE CENTER OF THE 1039MB HIGH REMAINING EAST OF THE AREA TONIGHT...NORTHWEST WINDS WILL CONTINUE AT ENOUGH OF A SPEED FOR RARE MARCH WIND CHILL CONCERNS...BUT NOT SURPRISING GIVEN THE FORTITUDE OF THIS COOL SEASON. THE AFOREMENTIONED CLOUDS AND WINDS SHOULD HELP TO OFFSET RAPID EVE COOLING...BUT A SLOW STEADY DROP IS ANTICIPATED. OUTSIDE OF CHICAGO...LOWS ARE FORECAST TO DROP TO BELOW ZERO IN MOST AREAS. SEE THE CLIMATE DISCUSSION BELOW FOR MORE. THE WIND CHILLS FALL OUT AT -15 TO -25 ACROSS NORTH CENTRAL ILLINOIS AND THE NORTH AND FAR WEST SIDES OF THE CHICAGO METRO WHICH IS WORTHY OF AN ADVISORY. MONDAY... THE HIGH WILL MOVE DIRECTLY OVER THE REGION WITH SOME SUNSHINE. IT IS ALWAYS A BATTLE THIS TIME OF YEAR WITH COLD AIR OVER SNOW COVER VERSUS THE INCREASING SUN ANGLE. GIVEN THE 925MB TEMPS OF -16C FORECAST AND OVER SNOW COVER...CLIMATOLOGICALLY THIS WOULD FAVOR FORECAST HIGH IN THE TEENS AND HAVE GONE THAT ROUTE. AGAIN SEE THE CLIMATE DISCUSSION BELOW FOR THE RECORD LOW MAXS. CLOUDS LOOK TO BE ON THE INCREASE RAPIDLY MONDAY NIGHT AND THAT SHOULD KEEP MINS UP FROM WHAT WOULD OTHERWISE BE ANOTHER NIGHT BELOW ZERO IN MANY PLACES. IF CLOUDS DO COME IN SLOWER DURING THE EVE THAT COULD LEAD TO A MORE RAPID DROP...BUT RIGHT NOW CONFIDENCE IN CLOUD COVER IS FAIRLY HIGH. TUESDAY AND BEYOND... THE UNSETTLED WEST NORTHWEST FLOW STILL LOOKS TO PREVAIL DURING MIDWEEK. WITH THE QUICK PROGRESSIVE NATURE OF THESE SYSTEMS...NAMELY EARLY TUESDAY AND THEN AGAIN TUESDAY NIGHT AND EARLY WEDNESDAY...IT IS NOT SURPRISING TO SEE CONTINUED MODEL SPREAD. BELIEVE THAT THE FIRST DISTURBANCE EARLY TUESDAY WILL REMAIN PRIMARILY TO THE NORTH GIVEN THE DRY RIDGING OVER THE AREA. THE ELEVATED BAROCLINIC ZONE SHIFTS SOMEWHAT SOUTH IN ITS WAKE...WHICH WOULD ALLOW THE THE TUESDAY NIGHT/EARLY WED SYSTEM A LITTLE BETTER CHANCE TO IMPACT THE AREA. AGAIN THERE IS LITTLE LOW-LEVEL INFLUENCE WITH THIS SYSTEM AND DEEP MOISTURE VALUES LOOK LOW...SO ANY SNOW AMOUNTS WOULD APPEAR MINOR IF IT WERE TO MATERIALIZE...BUT SOMETHING THAT COULD HAVE IMPACTS DEPENDING ON THE TIMING. MODEL SPREAD REALLY GETS LARGE BEYOND THAT AND SO HAVE NOT MADE ANY MAJOR CHANGES TO POPS. HAVE INCREASED THEM SOMEWHAT LATE IN THE WEEK INTO SATURDAY. BESIDES THE FACT IT ALWAYS SNOWS ON SATURDAY /PARTIALLY JOKING/...THE EC AND GEM BOTH HAVE A TIGHT BAROCLINIC ZONE AND AN UPPER DISTURBANCE SIMILAR TO THIS PAST SATURDAY NIGHTS DROPPING SOUTHEAST ACROSS THE AREA. TEMPERATURES LOOK TO REMAIN BELOW NORMAL THIS WEEK WITH LIMITED DURATION PERIODS OF RETURN FLOW. THERE DOES STILL APPEAR TO BE A WINDOW OF ABOVE FREEZING TEMPS ON FRIDAY DEPENDING ON WHICH MODEL IS LOOKED AT...WHICH WOULD BE THE RETURN FLOW PERIOD AHEAD OF A POSSIBLE NEXT WEEKEND SYSTEM. OVERALL CONFIDENCE IS FAIRLY MINIMAL IN MOST FORECAST ELEMENTS FROM TUESDAY ONWARD. MTF && .CLIMATE... 258 PM CST THE FOLLOWING RECORDS INDICATED BY AN (*) ARE FORECAST TO BE BROKEN TONIGHT AND MONDAY: MARCH 3RD RECORD LOW MARCH 3RD RECORD LOW MAX CHICAGO: -6 (1873) 8 (1873) ROCKFORD: -4 (2002)* 18 (2002)* && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 03Z... * NORTH-NORTHWEST WINDS AROUND 10 KT GRADUALLY DIMINISHING THROUGH TONIGHT. * LOW CONFIDENCE IN DIRECTION OF LIGHT WINDS MONDAY IN VICINITY OF SURFACE HIGH PRESSURE RIDGE. RATZER //DISCUSSION...UPDATED 00Z... COLD/DRY HIGH PRESSURE RIDGE BUILDING SOUTHEAST FROM THE NORTHERN PLAINS INTO THE MIDWEST THROUGH MONDAY. VFR CONDITIONS AND GRADUALLY DECREASING NORTH-NORTHWEST WINDS ARE THE MAIN FEATURES THROUGH TONIGHT...THOUGH LOWER CONFIDENCE IN WIND FIELDS MAINLY DURING THE DAY MONDAY FOR ORD/MDW WITH WEAK PRESSURE GRADIENT INTERACTS WITH LAKE MICHIGAN. FOR TONIGHT...ONLY COMPLICATION IS WHERE WINDS HAD TURNED NORTHEAST ACROSS KMDW THIS AFTERNOON. VARIOUS OBSERVATIONAL DATA AND HIGH-RES MODEL TRENDS INDICATE WIND DIRECTION SHOULD TREND BACK MORE NORTH OR NORTH-NORTHEAST AT KMDW EARLY THIS EVENING. OTHER LOCATIONS EXPECTED TO REMAIN NORTH-NORTHWEST THROUGH TONIGHT WITH SPEEDS AROUND 10 KT VERY GRADUALLY DIMINISHING THROUGH THE NIGHT. BY MONDAY MORNING...SURFACE HIGH CENTER BEGINS TO SPREAD INTO THE FORECAST AREA WITH GRADIENT WEAKENING SIGNIFICANTLY BY MID-DAY. GUIDANCE VARIES WITH WIND DIRECTIONS AT THE SURFACE IN THE PRESENCE OF THE WEAK PRESSURE GRADIENT...THOUGH INSPECTION OF MODEL FORECAST SOUNDINGS DO INDICATE NORTH-NORTHEASTERLY FLOW JUST ABOVE THE BOUNDARY LAYER. THIS...AND SFC WIND FORECAST FROM SOME OF THE HIGHER-RES ARW MODELS SUGGEST THE POTENTIAL FOR A LIGHT NORTHEAST OR EAST WIND TO DEVELOP ACROSS ORD/MDW/GYY WHICH IS NOT INDICATED BY LOWER RESOLUTION MODELS. HAVE TRENDED FORECAST TOWARD THIS...PARTICULARLY AT KMDW/KGYY WHERE IT APPEARS SOME FORM OF FLOW OFF LAKE IS MORE PROBABLE. AT KORD...WENT VARIABLE WITH THE WIND DIRECTION DURING THE MID-DAY/AFTERNOON HOURS. OUR VERY WINTER- LIKE TEMPERATURE REGIME AND HEAVILY ICE-COVERED LAKE ARE NOT TYPICAL CLASSIC LAKE BREEZE CONDITIONS...THOUGH OFTEN WINDS WILL TURN OFF THE LAKE JUST FROM FRICTIONAL DIFFERENCES IN LAND/LAKE SURFACES. WIND WILL THEN BECOME LIGHT SOUTH ALL LOCATIONS MONDAY EVENING AS THE SURFACE HIGH MOVES OFF TO THE EAST. AS WINDS IN 2000-3000 FT AGL LEVEL MONDAY DO LOOK LIKELY TO BE FROM THE NORTHEAST...WHICH MIGHT SUPPORT SOME SCT CLOUDS OFF THE LAKE ...ALTHOUGH THE COMBINATION OF SUBSIDENCE...A VERY DRY AIR MASS AND UPSTREAM LAKE ICE COVER ALL ARGUE AGAINST ANY PERSISTENT CEILING. OTHERWISE...ONLY VFR HIGH CIRRUS IS EXPECTED WITH SOME PATCHY MID (120-150 KFT) DEVELOPING MAINLY OFF TO OUR NORTH AND WEST LATER MONDAY. RATZER //ORD AND MDW CONFIDENCE...UPDATED 03Z... * MEDIUM CONFIDENCE IN WIND DIRECTIONS ESPECIALLY MID-MORNING THROUGH AFTERNOON MONDAY. * HIGH CONFIDENCE ALL OTHER ELEMENTS. RATZER //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z... TUESDAY THROUGH THURSDAY...MAINLY VFR WITH PERIODIC CHANCES OF LIGHT SNOW...ESPECIALLY TUESDAY/TUESDAY NIGHT. FRIDAY AND SATURDAY...CHANCE OF LIGHT RAIN OR SNOW FRIDAY AND A CHANCE OF SNOW SATURDAY. PERIODS OF MVFR/IFR POSSIBLE. RATZER && .MARINE... 129 PM CST NORTHERLY WINDS WILL CONTINUE TONIGHT...ESPECIALLY ACROSS THE SOUTHERN HALF TO TWO THIRDS OF THE LAKE...AS A STOUT AND EXPANSIVE CANADIAN HIGH PRESSURE SYSTEM CONTINUES TO BUILD FROM THE NORTHERN PLAINS ACROSS THE UPPER MIDWEST. LAKE EFFECT PROCESSES WILL LIKELY CONTINUE TO LEAD TO SMALLER SCALE DISTURBANCES MOVING SOUTHWARD DOWN THE LAKE...AND THIS WILL RESULT IN SOME LOCAL WIND DIRECTION AND SPEED DIFFERENCES ALONG THE SOUTHERN PORTIONS OF THE LAKE TONIGHT. THE WINDS WILL ABATE ON MONDAY...LIKELY BECOMING UNDER 10 KT OVER THE SOUTHERN PORTION OF THE LAKE AS THE SURFACE HIGH MOVES OVER HEAD. SEVERAL WEAK WEATHER SYSTEMS ARE EXPECTED TO AFFECT THE GREAT LAKES REGION THROUGH THE WEEK. HOWEVER...NO SIGNIFICANT WIND EVENTS ARE CURRENTLY ANTICIPATED. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WIND CHILL ADVISORY...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011 UNTIL 9 AM MONDAY. WIND CHILL ADVISORY...ILZ005-ILZ006-ILZ012-ILZ019-ILZ020 UNTIL 9 AM 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/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
  [top] Area Forecast Discussion National Weather Service Lincoln IL 844 PM CST Sun Mar 2 2014 .DISCUSSION... ISSUED 835 PM CST Sun Mar 2 2014 Storm system well to our south continues to make progress across the Southern Plains this evening. A large shield of precipitation extends northeast from the upper wave, which was located over the Panhandle of Texas. On the northern periphery of the precipitation there was mainly snow being reported over parts of south central and southeast Illinois, with a wintry mix of sleet, freezing rain and snow over extreme southern Illinois into western Ky. The bulk of the significant precip will be occurring tonight south of I70 as another sprawling Arctic air mass settles southeast into the region through Monday. Will be cancelling the northern portion of the Winter Storm warning over southeast Illinois and if precip trends continue to suggest a southeast shift in the heavier bands of snow and sleet, we may be able to cancel most if not all of the warning over the far southeast later tonight. Further to the northwest, the wind chill advisory looks fine at this point, but satellite data showing quite a bit of cirrus well off to our northwest, so that may have an affect on our early morning lows. Forecast soundings off the RAP and the latest NAM- WRF suggest the thicker cirrus shield will shift into parts of southeast Illinois by morning, so will not make any changes to the wind chill headlines for the overnight hours. After we make the adjustment to the Winter Storm Warning over the southeast counties, we will send out an updated ZFP. Smith && .AVIATION... ISSUED 515 PM CST Sun Mar 2 2014 A second wave of snow has passed just south of SPI and DEC taf sites late this afternoon. Although a brief period of some very light snow or flurries will be possible, the steadier snow will remain south this evening. Otherwise, all sites will experience VFR conditions for this forecast period (thru 00z Tue). Another large Arctic high will gradually settle southeast into the Midwest on Monday bringing unseasonably cold temps to the region. Gusty northerly winds of 12 to 17 kts are expected tonight and then a gradual decrease to 10 to 15 kts will occur by Monday afternoon. Smith && .PREV DISCUSSION... ISSUED 252 PM CST Sun Mar 2 2014 High pressure ridge axis over the center of the country trying to push the current storm further out of the area, but the main portion of the wave still in Arkansas. The sfc low, however, is progged to move just south of the Ohio River Valley. The storm will still produce plenty of precip issues, though most of them, including the majority of the deformation zone enhancement, will fall south of ILX this evening. Though much of the weather has ended across the northern tier of the CWA, redeveloping snow across the center of the state, and still plenty of snow/sleet/fzra mix in the southeast is keeping some of the headlines active this afternoon. Models now moving the precip out of the area a little sooner, and as long as the low continues on its forecast track SE of the forecast area, an early cancellation is anticipated. Into the rest of the forecast, the models are just fine with the overall pattern, but off with the timing of the next couple waves. These systems are not big precip makers at this point, and the forecast is mostly quiet. SHORT TERM...Tonight and Tomorrow... Winter storm wrapping up this evening, but still producing plenty of precip for the southeast. Another 1 to 3 inches of snow anticipated in the warning area, in addition to slowly transitioning sleet to snow. FA should be dry by morning. IN the meantime, temperatures dropping quickly behind the system in areas to the NW where some clearing is anticipated. Negative single digit temps North of the I-55 corridor and winds staying up in 7-15 kt range through the overnight resulting in wind chills from -15 to -20 degrees. Wind Chill Advisory is out as a result for the overnight hours and a very cold start to Monday. High pressure ridge moving closer through the day, and winds will go light and variable before switching back around to having a more southerly component. Although tomorrow night will also be cold, it will remain above zero, in the positive single digits. LONG TERM...Tuesday through Saturday... More cold air for the extended. Mon-Thursday still well below freezing. Although Friday is showing signs of a warm up, but the WAA looks a bit weak at this point. Suspicious that the MOS is being pulled too much by guidance upwards, considering that it has cooled off again with this synoptic run. Brief waves bringing quick shot of precip possibly on Wed across the north, with only slight chc pops north of I-74 corridor from GBG to PIA. ECMWF and GFS still not in agreement with the next wave btwn Thursday and Saturday night. GFS quicker and divided the energy out ahead of a trof digging in over the desert SW. GFS sends two quick shots of precip and ECMWF sends only one, along a developing baroclinic zone, while splitting the flow at 500 mb. Another pattern shift, and will likely see the models vary quite a bit as time progresses. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING until 6 AM CST Monday FOR ILZ054>057- 061>063-066>068-071>073. WIND CHILL ADVISORY until 10 AM CST Monday FOR ILZ027>031- 036>038-040>043-047>051. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1026 AM CST SAT MAR 1 2014 .DISCUSSION... 400 AM CST MAIN CONCERN FOR THE FORECAST PERIOD WILL BE THE POTENTIAL FOR HEAVY SNOW THROUGH THE WEEKEND. FOR THE REMAINDER OF THE OVERNIGHT HOURS...A WEAK SHORTWAVE INVOF THE LEFT EXIT REGION OF A STRONG UPPER LEVEL JET IS PROVIDING THE DYNAMICS TO GENERATE A QUICK ROUND OF SNOW EARLY THIS MORNING. WITH ONLY WEAK SFC TROUGHING AND VERY MODEST LOW LEVEL FORCING...THE SNOW IS ALMOST ENTIRELY RELYING ON UPPER LEVEL DYNAMICS TO SUPPORT THE SNOW GENERATION. LATEST RADAR TRENDS INDICATE THAT THE BAND OF SNOW EXTENDS FROM WAUKEGAN TO PERU AND IS MOVING VERY QUICKLY TO THE EAST. THE SNOW WILL END SHORTLY IN THE ROCKFORD AREA AND WILL QUICKLY PUSH PAST THE CHICAGO METRO AREA SHORTLY AFTER DAYBREAK...AND EVEN ENDING OVER THE FAR EASTERN PORTIONS OF THE CWA BY LATE THIS MORNING. SINCE THE SYSTEM IS MOVING SO QUICKLY...ONLY AROUND AN INCH OF ACCUMULATION IS EXPECTED. THE MAIN SNOW CONCERN IS SETTING UP FOR LATE THIS AFTERNOON...AND PERSISTING ACROSS PORTIONS OF THE REGION UNTIL LATE SUNDAY NIGHT. GIVEN THE LONG DURATION OF THE EVENT...HAVE OPTED TO ISSUE A WINTER WEATHER ADVISORY FOR THE ENTIRE CWA. THE ADVISORY WILL BE IN 2 SEGMENTS...BEGINNING EARLIER FOR LOCATIONS NORTH OF THE ILLINOIS AND KANKAKEE RIVERS...AND THEN SPREADING SOUTH OVERNIGHT TONIGHT. THE MAIN FEATURE OF CONCERN IS A STRONG CLOSED UPPER LOW OFF THE CENTRAL CALIFORNIA COAST. THE GUIDANCE HAS CONVERGED INTO RELATIVELY GOOD AGREEMENT IN THE LARGER SCALE DETAILS WITH THE SYSTEM EVOLVING INTO AN OPEN WAVE AS THE SYSTEM MOVES ON SHORE LATE THIS AFTERNOON. THIS WILL SET UP A STREAM OF SWLY FLOW ALOFT AS WEAK UPPER RIDGING BUILDS OVER THE CENTRAL CONUS AND THE UPPER TROUGH DIGS OVER THE WEST. A BROAD UPPER LOW CENTERED OVER HUDSON BAY...WITH TROUGHING THROUGH THE UPPER GREAT LAKES WILL SQUEEZE THE UPPER LEVEL FLOW...SETTING UP VERY FAST FLOW ALOFT RIPPLES OF SHORT WAVE ENERGY EJECTING OUT OF THE SOUTHERN ROCKIES WITH A DIRECT TRAJECTORY ACROSS THE MIDDLE MISSISSIPPI VALLEY TO THE GREAT LAKES. AT THE SURFACE...POLAR HIGH PRESSURE WILL BUILD OUT OF CANADA AND SPREAD ACROSS THE NORTHERN PLAINS AND INTO THE MIDDLE AND UPPER MISSISSIPPI VALLEY TODAY. AFTER A RELATIVELY MILD FRIDAY...THIS AREA OF HIGH PRESSURE WILL BRING AN ARCTIC AIRMASS BACK TO THE REGION AT THE SFC. THE SNOW WILL AGAIN LARGELY BE DRIVEN BY UPPER LEVEL DYNAMICS...WITH THE BAND OF STRONGEST FORCING SAGGING SOUTHWARD THROUGH THE CWA. CURRENTLY...ANTICIPATE THAT THE SNOW WILL BEGIN OVER THE NWRN PORTIONS OF THE CWA...INCLUDING THE ROCKFORD METRO AREA BY AROUND 3PM THIS AFTERNOON AND GRADUALLY SPREAD SOUTH AND EAST...WITH HEAVIER SNOW REACHING THE CHICAGO METRO AREA DURG THE EARLY EVENING HOURS. AS THE UPPER LEVEL TROUGHING EXTENDING FROM HUDSON BAY BACK TOWARD SOUTH CENTRAL CANADA BEGINS TO DIG SOUTHWARD ACROSS THE UPPER GREAT LAKES LATE TONIGHT AND EARLY SUNDAY...THE AREA OF SNOW WILL BE QUICKLY FORCED SOUTH...WITH SNOW ENDING OVER THE NORTHERN TIER COUNTIES BY EARLY SUNDAY MORNING. HOWEVER...THE MAIN SHORTWAVE TROUGH ASSOCIATED WITH THE PACIFIC SYSTEM WILL EJECT OUT OF THE SOUTHERN ROCKIES BY SUNDAY MORNING AND TRACK ACROSS THE PLAINS TO THE MIDDLE MISSISSIPPI VALLEY BY SUNDAY NIGHT...AND THEN PUSH QUICKLY EAST OF THE AREA BY EARLY MONDAY MORNING. WHILE THE CANADIAN TROUGH WILL FORCE AN END TO THE SYNOPTIC SNOW OVER THE NRN PORTIONS OF THE BY EARLY SUNDAY MORNING...THE PACIFIC SHORTWAVE ENERGY WILL KEEP THE SNOW POTENTIAL GOING OVER THE SRN PORTIONS OF THE CWA THROUGH LATE SUNDAY NIGHT. ALL TOTAL...EXPECT AROUND 3 TO 5 INCHES ACCUMULATION OF RELATIVELY DRIER SNOW OVER THE NORTHERN PORTIONS OF THE CWA...AND 5 TO 7 INCHES OVER THE SOUTHERN PORTIONS OF THE CWA...THOUGH THE SNOW OVER THE SOUTHERN LOCATIONS MAY LIKELY CONTAIN SLIGHTLY HIGHER LIQUID WATER CONTENT DUE TO THE LONGER DURATION OF THE PACIFIC SYSTEM IMPACTING THE REGION. AS THE SYNOPTIC SNOW TAPERS OFF OVER THE NORTHERN PORTIONS OF THE CWA EARLY SUNDAY MORNING...THE SFC HIGH PRESSURE WILL SPREAD EAST ACROSS THE UPPER MISSISSIPPI VALLEY AND THE GREAT LAKES REGION. THE LARGER SCALE MODELS...IN PARTICULAR...THE GFS...HAVE BEEN ADVERTISING THE POTENTIAL FOR A LAKE EFFECT BAND OF SNOW TO DEVELOP OVER LAKE MICHIGAN BY SUNDAY MORNING. THE SHORTER RANGE HIGH RES GUIDANCE IS NOW SHOWING A SIMILAR SETUP WITH SFC CONVERGENCE SETTING UP OVER WESTERN LAKE MICHIGAN. THIS COULD BRING PERIODS OF LAKE EFFECT SNOW SHOWERS TO FAR NERN IL...AND EVENTUALLY FAR NWRN INDIANA AS THE LAKE PLUME MIGRATES EWD INTO EARLY MONDAY MORNING. GIVEN THE EXTENSIVE ICE COVER ON LAKE MICHIGAN AND RELATIVELY COLD SFC WATER TEMPERATURES...INVERSION HEIGHTS WILL BE RELATIVELY SHALLOW AND EQUILIBRIUM LEVELS ONLY AROUND 5-6KFT AND CAPE VALUES OF 300-400 J/KG. THE MODEST CONVECTIVE DEPTH AND INSTABILITY WOULD SUGGEST THAT SIGNIFICANT LAKE EFFECT SNOW IS NOT LIKELY...BUT PERIODS OF LAKE EFFECT SNOW SHOWERS PRODUCING ADDITIONAL LIGHT ACCUMULATIONS OVER THE CHICAGO METRO AREA ARE CERTAINLY POSSIBLE SUNDAY AND SUNDAY NIGHT. AS THE COLD HIGH PRESSURE SETTLES OVER THE REGION EARLY NEXT WEEK...THE REGION CAN EXPECT A FEW MORE DAYS WITH LOW TEMPERATURES RANGING FROM THE SINGLE DIGITS ABOVE ZERO TO THE SINGLE DIGITS BELOW ZERO. BRISK NORTH WINDS SHOULD DRIVE WIND CHILL READING TO AROUND 5 TO 15 BELOW ZERO FOR SUNDAY MORNING. AS THE CENTER OF THE HIGH SETTLES OVER IOWA BY MONDAY MORNING...COLD ADVECTION WILL DRIVE TEMPERATURES BELOW ZERO FOR PORTIONS OF THE AREA GENERALLY WEST OF THE I-57 CORRIDOR AND THE FOX VALLEY...WHERE TEMPERATURES COULD DIP TO AROUND 5 BELOW ZERO...WITH WIND CHILLS TO 20 BELOW ZERO. THE CENTER OF THE HIGH WILL MOVE OVER THE AREA FOR TUESDAY MORNING...SO CLEAR SKIES...LIGHT WINDS AND FRESH SNOW COVER WILL ALLOW FOR MORE WIDESPREAD LOWS BELOW ZERO DUE TO RADIATIVE COOLING. FOR THE EXTENDED FORECAST PERIOD...FOR TUESDAY THROUGH FRIDAY...THE LONGER RANGE GUIDANCE CONTINUES TO ADVERTISE A GRADUAL WARMING TREND BY THE END OF THE PERIOD. WEDNESDAY SHOULD REMAIN RELATIVELY COOL WITH HIGHS STILL ONLY IN THE MIDDLE 20S...BUT AS THE ARCTIC HIGH MOST WELL TO THE EAST BY THURSDAY...SETTING UP A WARM ADVECTIVE PATTERN...TEMPERATURES SHOULD REBOUND INTO THE LOWER 30S BY THURSDAY AND COULD EVEN PEG 40F BY FRIDAY. A SERIES OF MID LEVEL SHORTWAVES COULD BRING PERIODIC CHANCES FOR SOME LIGHT SNOW ON WEDNESDAY AND THURSDAY...BUT NOTHING SIGNIFICANT IS LIKELY. KREIN && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * NORTH WINDS LATE THIS MORNING WITH LINGERING POCKETS OF MVFR CIGS. EXPECT A PERIOD OF VFR BEFORE SNOW ARRIVES. * SNOW ARRIVING THIS AFTERNOON. MOVED UP START TIME BY AN HOUR AND LOWERED INITIAL VSBYS TO MVFR. ALSO MOVED UP START TIME OF HEAVIER SNOW. IFR LIKELY AND LIFR POSSIBLE THIS EVENING. LENNING //DISCUSSION...UPDATED 12Z... LAST OF THE LIGHT SNOW CONTINUES TO EXIT THE TERMINALS EARLY THIS MORNING. A BAND OF IFR CIGS HAS DEVELOPED IN THE WAKE OF THE BAND BUT SHOULD BE PROGRESSING EAST AWAY FROM THE TERMINALS IN THE NEXT FEW HOURS. VARIABLE MVFR/VFR CIGS EXTEND BACK TO THE MISSISSIPPI RIVER OR SO WITH STEADIER VFR TO THE WEST. WINDS HAVE OR WILL BE TURNING NORTHERLY SHORTLY AND EXPECT THAT THERE WILL BE FLUCTUATIONS BETWEEN NW AND NNE THROUGH THE DAY. ATTENTION TURNS TO THE NEXT ROUND OF MORE SIGNIFICANT SNOW WHICH WILL ARRIVE LATER THIS AFTERNOON FROM WEST TO EAST. SNOW SHOULD QUICKLY INCREASE IN INTENSITY LATE THIS AFTERNOON AT RFD AND RIGHT AROUND 00Z IN THE CHICAGO AREA...THOUGH LIGHT SNOW MAY DEVELOP JUST PRIOR TO THAT. TIMING MAY STILL NEED SOME TWEAKING BUT HAVE GOOD CONFIDENCE OVERALL. PERIOD OF MODERATE TO EVEN BRIEFLY HEAVY SNOW ARE EXPECTED FROM LATE THIS AFTERNOON INTO MID EVENING AT RFD AND PRIMARILY DURING THE EVENING IN THE CHICAGO AREA. PREVAILING VSBY OF 1 TO 1.5SM IS LIKELY WITH PERIODS OF 1/2 TO 3/4SM VSBY POSSIBLE AS WELL. CANNOT RULE OUT SOME BRIEF PERIODS OF 1/4SM AS WELL. ACCUMULATION RATES OF 0.5 TO 1 INCH PER HOUR ARE ALSO LIKELY AT TIMES. THE MAIN FORCING FOR THE SNOW WILL PUSH SOUTHWARD FROM LATE EVENING INTO THE OVERNIGHT ALLOWING SNOW INTENSITY TO TAPER OFF AT THE TERMINALS...THOUGH SOME LIGHT SNOW MAY CONTINUE THROUGH DAYBREAK. LAKE EFFECT PROCESSES WILL THEN TRY TO TAKE OVER WHICH SHOULD LEAD TO LAKE EFFECT SNOW SHOWERS. THE CHALLENGE WILL BE DETERMINING THE LOCATION AND INTENSITY DETAILS. WITH A SLIGHT NORTHEAST WIND COMPONENT TO THE WINDS SOME OF THIS ACTIVITY MAY DRIFT TOWARD OR OVER ORD/MDW DURING THE DAY SUNDAY. SHOULD THIS OCCUR THEN PERIODIC BURSTS OF MORE INTENSE SNOW WILL BE POSSIBLE WITH GREATLY REDUCED VSBY. GYY IS PROBABLY THE MOST FAVORED FOR LAKE EFFECT ACTIVITY GIVEN THE PRIMARILY NORTH WIND BU OVERALL CONFIDENCE IS LIMITED SO CONTINUE TO MONITOR FOR THE LATEST THINKING. MDB //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH CONFIDENCE ON WINDS REMAINING NORTHERLY. * MEDIUM CONFIDENCE ON TIMING OF SNOW AND CIG/VSBY TRENDS. HIGH CONFIDENCE OF IFR PERIODS THIS EVENING. LENNING //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...CHANCE FOR SNOW SHOWERS WITH IFR/MVFR POSSIBLE. MONDAY THROUGH FRIDAY...MAINLY VFR WITH PERIODIC LOW CHANCES FOR LIGHT SNOW. MDB && .MARINE... 302 AM CST LOW PRESSURE JUST EAST OF NORTHERN LAKE SUPERIOR WILL MOVE EASTWARD INTO WESTERN QUEBEC INTO THE EARLY AFTERNOON HOURS. A COLD FRONT IS TRAILING THIS LOW AND IS PUSHING ACROSS LAKE MICHIGAN EARLY THIS MORNING BRINGING A SHIFT TO NORTH AND NORTHWEST WINDS. SPEEDS WILL INCREASE INTO THE 15 TO 25 KT RANGE BEHIND THE FRONT THIS MORNING THEN EASE UP A BIT THIS EVENING. NORTHERLY WINDS WILL CONTINUE THROUGH SUNDAY WITH SOME CONVERGENCE LIKELY SETTING UP ACROSS CENTRAL AND SOUTHERN SECTIONS OF THE LAKE AS LAKE EFFECT PROCESSES TAKE OVER. AS THIS OCCURS AN INVERTED TROUGH WILL DEVELOP FROM SOUTHWEST TO NORTHEAST ACROSS THE OHIO VALLEY THEN SHIFT SOUTHWARD SUNDAY AND MONDAY. STRONG HIGH PRESSURE CENTERED OVER ALBERTA AND ITS ASSOCIATED RIDGE EXTENDING SOUTHEASTWARD INTO THE CENTRAL PLAINS WILL DRIFT SOUTHEAST OVER THE NEXT SEVERAL DAYS. THE RIDGE AXIS WILL RE-ORIENT SOMEWHAT AND POSITION ITSELF ACROSS THE WESTERN GREAT LAKES LATER TONIGHT...BEFORE THE HIGH BECOMES CENTERED OVER THE PLAINS AND MID AND UPPER MISSISSIPPI RIVER VALLEY LATER SUNDAY. THE PRESSURE GRADIENT LOOKS TO TIGHTEN ACROSS LAKE MICHIGAN SUNDAY NIGHT ALLOWING NORTHERLY WINDS TO INCREASE ONCE AGAIN. THE HIGH WILL MOVE EASTWARD MONDAY ALLOWING WINDS TO DROP OFF AND BECOME VARIABLE. AS THE HIGH PASSES WINDS SHIFT TO THE EAST AND SOUTHEAST FOR MID WEEK BEFORE TURNING SOUTHERLY LATE IN THE WEEK. MDB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008- ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021- ILZ022...3 PM SATURDAY TO 9 AM SUNDAY. WINTER WEATHER ADVISORY...ILZ023-ILZ032-ILZ033-ILZ039...9 PM SATURDAY TO MIDNIGHT MONDAY. IN...WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019...9 PM SATURDAY TO MIDNIGHT MONDAY. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1013 AM CST Sat Mar 1 2014 .DISCUSSION... ISSUED 1011 AM CST Sat Mar 1 2014 Cold front has reached the I-70 corridor as of 10 am, and will continue to move through the southeast CWA into early afternoon. High temperatures further northwest have already occurred, and falling temperatures will be the trend through the afternoon as Arctic air upstream pushes southeastward. Large area of light snow has set up over the north half of Iowa and will be tracking eastward much of the day, before taking a southeast nudge later this afternoon. Have adjusted PoP`s for the afternoon to focus them on the 3-6 pm time frame as a result. Other adjustments to hourly temperature trends have been sent. Will hold onto the Winter Storm Watch until all of the 12Z model guidance has arrived, before making the decision on how to convert it. Geelhart && .AVIATION... ISSUED 510 AM CST Sat Mar 1 2014 IFR CIGs behind cold front beginning to work into central Illinois from the northwest. KGBG has dropped to OVC007 and large area of CIGs between 007 and 012 extends approximately 100 nm behind the cold front. Although diurnal influence may raise the CIGs slightly as they work southeast, latest HRRR suggest the band will hold together much of the day. Have translated the IFR/MVFR clouds into the terminals this morning as front pushes through. So far only minor reductions in VSBYs and will leave as P6SM for now. Jet streak induced broad area of snow is expected to develop across the upper Mississippi Valley this afternoon and advect southward into the terminals this evening. Will likely be occasional VSBYs lower, will currently broad brush with 2 nm. As the area develops later packages can hone the details on exactly when LIFR VSBYs might occur. Barker && .PREV DISCUSSION... ISSUED 328 AM CST Sat Mar 1 2014 SHORT TERM...Today through Sunday At 08Z/2AM Arctic cold front was just entering the NW CWA accompanied by a narrow band of light snow, which has briefly dropped vsbys to 3-5 miles. Latest trends and short range models indicate what snow there is will dissipate as the front continues to shift southeast this morning. Did include low chance pops this afternoon across the northern third where models show weak omega behind front off weak dpva. As the Arctic front shifts south towards the Ohio Valley this evening, a strong 140+ kt 300mb jet sets up over the Great Lakes. This in conjunction with a tightening mid-level baroclinic zone to our south sets up good moisture transport into a region of strong frontogenesis over Iowa and northern IL. As this zone gradually shifts south this evening, expect snow to increase in coverage and intensity. Given the strength of projected frontogenesis and a hint of negative EPV above this zone would expect some banding and enhance snowfall rates overnight. 00Z guidance has trended more progressive the the band of stronger forcing, shifting this south of I-72 Sunday morning. This seems reasonable given the fact this is an open wave at 850/700 mb. Snow will likely continue over the southern half Sunday afternoon, and into Sunday night far SE, as additional shortwave energy ejects from southern plains trough. Thermal profiles off consistent GFS/ECMWF show snow for much of the CWA, except south of I-70 where a sleet/freezing rain mix is possible for several hours after onset. Have discounted aggressive warmer NAM thermal structure (which would bring mixed precip north of I-72) due to open wave feature. This does lead to lower overall confidence in p-type than would be desired at 24 hrs. Given precipitable water values 0.6-0.9 and projected forcing, model qpf raning from 0.3 NW to 0.75 SE looks reasonable. Used 12:1 snow:liquid ratio, except 10:1 south of I-70 due to thermal profiles. For the northwest half of the CWA projected totals of 4-6" in 18+ hours fall short of warning criteria (6"+ in 12 hours or 8"+ in 24 hours) and have issued winter wx advisory for 6 PM tonight through 6 PM Sunday. For areas southeast of a Shebyville to Monticello to Rantoul line, 5-8" forecast over a 24+ hour period also falls short of warning criteria. The potential for mixed precip does complicate things, as warning sleet/ice accums would be possible under NAM solution. With uncertainty remaining in this area will keep winter storm watch going (midnight tonight through 6 AM Monday morning), and let day shift make the call after looking over 12Z data. LONG TERM...Monday through Friday Bitterly cold air moves into the region behind the departing storm. Late season Arctic high pressure will produce temps 20-25 degrees below normal, with lows likely dropping below zero across the north Monday and Tuesday mornings. A weak shortwave dropping through in northwest flow behind the high, will bring a chance of light snow to the northern half of the CWA Tuesday. With low moisture availability have kept pops to slight chance. While temps will remain below normal through the week, readings will gradually moderate as mid level flow flattens. Dry weather is expected as split flow keeps major systems well to our north and south. 25 && .ILX WATCHES/WARNINGS/ADVISORIES... WINTER STORM WATCH from late tonight through late Sunday night FOR ILZ044>046-054>057-061>063-066>068-071>073. WINTER WEATHER ADVISORY from 6 PM this evening to 6 PM CST Sunday FOR ILZ027>031-036>038-040>043-047>053. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
553 AM CST SAT MAR 1 2014 .DISCUSSION... 400 AM CST MAIN CONCERN FOR THE FORECAST PERIOD WILL BE THE POTENTIAL FOR HEAVY SNOW THROUGH THE WEEKEND. FOR THE REMAINDER OF THE OVERNIGHT HOURS...A WEAK SHORTWAVE INVOF THE LEFT EXIT REGION OF A STRONG UPPER LEVEL JET IS PROVIDING THE DYNAMICS TO GENERATE A QUICK ROUND OF SNOW EARLY THIS MORNING. WITH ONLY WEAK SFC TROUGHING AND VERY MODEST LOW LEVEL FORCING...THE SNOW IS ALMOST ENTIRELY RELYING ON UPPER LEVEL DYNAMICS TO SUPPORT THE SNOW GENERATION. LATEST RADAR TRENDS INDICATE THAT THE BAND OF SNOW EXTENDS FROM WAUKEGAN TO PERU AND IS MOVING VERY QUICKLY TO THE EAST. THE SNOW WILL END SHORTLY IN THE ROCKFORD AREA AND WILL QUICKLY PUSH PAST THE CHICAGO METRO AREA SHORTLY AFTER DAYBREAK...AND EVEN ENDING OVER THE FAR EASTERN PORTIONS OF THE CWA BY LATE THIS MORNING. SINCE THE SYSTEM IS MOVING SO QUICKLY...ONLY AROUND AN INCH OF ACCUMULATION IS EXPECTED. THE MAIN SNOW CONCERN IS SETTING UP FOR LATE THIS AFTERNOON...AND PERSISTING ACROSS PORTIONS OF THE REGION UNTIL LATE SUNDAY NIGHT. GIVEN THE LONG DURATION OF THE EVENT...HAVE OPTED TO ISSUE A WINTER WEATHER ADVISORY FOR THE ENTIRE CWA. THE ADVISORY WILL BE IN 2 SEGMENTS...BEGINNING EARLIER FOR LOCATIONS NORTH OF THE ILLINOIS AND KANKAKEE RIVERS...AND THEN SPREADING SOUTH OVERNIGHT TONIGHT. THE MAIN FEATURE OF CONCERN IS A STRONG CLOSED UPPER LOW OFF THE CENTRAL CALIFORNIA COAST. THE GUIDANCE HAS CONVERGED INTO RELATIVELY GOOD AGREEMENT IN THE LARGER SCALE DETAILS WITH THE SYSTEM EVOLVING INTO AN OPEN WAVE AS THE SYSTEM MOVES ON SHORE LATE THIS AFTERNOON. THIS WILL SET UP A STREAM OF SWLY FLOW ALOFT AS WEAK UPPER RIDGING BUILDS OVER THE CENTRAL CONUS AND THE UPPER TROUGH DIGS OVER THE WEST. A BROAD UPPER LOW CENTERED OVER HUDSON BAY...WITH TROUGHING THROUGH THE UPPER GREAT LAKES WILL SQUEEZE THE UPPER LEVEL FLOW...SETTING UP VERY FAST FLOW ALOFT RIPPLES OF SHORT WAVE ENERGY EJECTING OUT OF THE SOUTHERN ROCKIES WITH A DIRECT TRAJECTORY ACROSS THE MIDDLE MISSISSIPPI VALLEY TO THE GREAT LAKES. AT THE SURFACE...POLAR HIGH PRESSURE WILL BUILD OUT OF CANADA AND SPREAD ACROSS THE NORTHERN PLAINS AND INTO THE MIDDLE AND UPPER MISSISSIPPI VALLEY TODAY. AFTER A RELATIVELY MILD FRIDAY...THIS AREA OF HIGH PRESSURE WILL BRING AN ARCTIC AIRMASS BACK TO THE REGION AT THE SFC. THE SNOW WILL AGAIN LARGELY BE DRIVEN BY UPPER LEVEL DYNAMICS...WITH THE BAND OF STRONGEST FORCING SAGGING SOUTHWARD THROUGH THE CWA. CURRENTLY...ANTICIPATE THAT THE SNOW WILL BEGIN OVER THE NWRN PORTIONS OF THE CWA...INCLUDING THE ROCKFORD METRO AREA BY AROUND 3PM THIS AFTERNOON AND GRADUALLY SPREAD SOUTH AND EAST...WITH HEAVIER SNOW REACHING THE CHICAGO METRO AREA DURG THE EARLY EVENING HOURS. AS THE UPPER LEVEL TROUGHING EXTENDING FROM HUDSON BAY BACK TOWARD SOUTH CENTRAL CANADA BEGINS TO DIG SOUTHWARD ACROSS THE UPPER GREAT LAKES LATE TONIGHT AND EARLY SUNDAY...THE AREA OF SNOW WILL BE QUICKLY FORCED SOUTH...WITH SNOW ENDING OVER THE NORTHERN TIER COUNTIES BY EARLY SUNDAY MORNING. HOWEVER...THE MAIN SHORTWAVE TROUGH ASSOCIATED WITH THE PACIFIC SYSTEM WILL EJECT OUT OF THE SOUTHERN ROCKIES BY SUNDAY MORNING AND TRACK ACROSS THE PLAINS TO THE MIDDLE MISSISSIPPI VALLEY BY SUNDAY NIGHT...AND THEN PUSH QUICKLY EAST OF THE AREA BY EARLY MONDAY MORNING. WHILE THE CANADIAN TROUGH WILL FORCE AN END TO THE SYNOPTIC SNOW OVER THE NRN PORTIONS OF THE BY EARLY SUNDAY MORNING...THE PACIFIC SHORTWAVE ENERGY WILL KEEP THE SNOW POTENTIAL GOING OVER THE SRN PORTIONS OF THE CWA THROUGH LATE SUNDAY NIGHT. ALL TOTAL...EXPECT AROUND 3 TO 5 INCHES ACCUMULATION OF RELATIVELY DRIER SNOW OVER THE NORTHERN PORTIONS OF THE CWA...AND 5 TO 7 INCHES OVER THE SOUTHERN PORTIONS OF THE CWA...THOUGH THE SNOW OVER THE SOUTHERN LOCATIONS MAY LIKELY CONTAIN SLIGHTLY HIGHER LIQUID WATER CONTENT DUE TO THE LONGER DURATION OF THE PACIFIC SYSTEM IMPACTING THE REGION. AS THE SYNOPTIC SNOW TAPERS OFF OVER THE NORTHERN PORTIONS OF THE CWA EARLY SUNDAY MORNING...THE SFC HIGH PRESSURE WILL SPREAD EAST ACROSS THE UPPER MISSISSIPPI VALLEY AND THE GREAT LAKES REGION. THE LARGER SCALE MODELS...IN PARTICULAR...THE GFS...HAVE BEEN ADVERTISING THE POTENTIAL FOR A LAKE EFFECT BAND OF SNOW TO DEVELOP OVER LAKE MICHIGAN BY SUNDAY MORNING. THE SHORTER RANGE HIGH RES GUIDANCE IS NOW SHOWING A SIMILAR SETUP WITH SFC CONVERGENCE SETTING UP OVER WESTERN LAKE MICHIGAN. THIS COULD BRING PERIODS OF LAKE EFFECT SNOW SHOWERS TO FAR NERN IL...AND EVENTUALLY FAR NWRN INDIANA AS THE LAKE PLUME MIGRATES EWD INTO EARLY MONDAY MORNING. GIVEN THE EXTENSIVE ICE COVER ON LAKE MICHIGAN AND RELATIVELY COLD SFC WATER TEMPERATURES...INVERSION HEIGHTS WILL BE RELATIVELY SHALLOW AND EQUILIBRIUM LEVELS ONLY AROUND 5-6KFT AND CAPE VALUES OF 300-400 J/KG. THE MODEST CONVECTIVE DEPTH AND INSTABILITY WOULD SUGGEST THAT SIGNIFICANT LAKE EFFECT SNOW IS NOT LIKELY...BUT PERIODS OF LAKE EFFECT SNOW SHOWERS PRODUCING ADDITIONAL LIGHT ACCUMULATIONS OVER THE CHICAGO METRO AREA ARE CERTAINLY POSSIBLE SUNDAY AND SUNDAY NIGHT. AS THE COLD HIGH PRESSURE SETTLES OVER THE REGION EARLY NEXT WEEK...THE REGION CAN EXPECT A FEW MORE DAYS WITH LOW TEMPERATURES RANGING FROM THE SINGLE DIGITS ABOVE ZERO TO THE SINGLE DIGITS BELOW ZERO. BRISK NORTH WINDS SHOULD DRIVE WIND CHILL READING TO AROUND 5 TO 15 BELOW ZERO FOR SUNDAY MORNING. AS THE CENTER OF THE HIGH SETTLES OVER IOWA BY MONDAY MORNING...COLD ADVECTION WILL DRIVE TEMPERATURES BELOW ZERO FOR PORTIONS OF THE AREA GENERALLY WEST OF THE I-57 CORRIDOR AND THE FOX VALLEY...WHERE TEMPERATURES COULD DIP TO AROUND 5 BELOW ZERO...WITH WIND CHILLS TO 20 BELOW ZERO. THE CENTER OF THE HIGH WILL MOVE OVER THE AREA FOR TUESDAY MORNING...SO CLEAR SKIES...LIGHT WINDS AND FRESH SNOW COVER WILL ALLOW FOR MORE WIDESPREAD LOWS BELOW ZERO DUE TO RADIATIVE COOLING. FOR THE EXTENDED FORECAST PERIOD...FOR TUESDAY THROUGH FRIDAY...THE LONGER RANGE GUIDANCE CONTINUES TO ADVERTISE A GRADUAL WARMING TREND BY THE END OF THE PERIOD. WEDNESDAY SHOULD REMAIN RELATIVELY COOL WITH HIGHS STILL ONLY IN THE MIDDLE 20S...BUT AS THE ARCTIC HIGH MOST WELL TO THE EAST BY THURSDAY...SETTING UP A WARM ADVECTIVE PATTERN...TEMPERATURES SHOULD REBOUND INTO THE LOWER 30S BY THURSDAY AND COULD EVEN PEG 40F BY FRIDAY. A SERIES OF MID LEVEL SHORTWAVES COULD BRING PERIODIC CHANCES FOR SOME LIGHT SNOW ON WEDNESDAY AND THURSDAY...BUT NOTHING SIGNIFICANT IS LIKELY. KREIN && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * IFR CIGS IMPROVING TO VARIABLE MVFR/VFR NEXT 1-2 HOURS. * MORE SNOW ARRIVES LATE THIS AFTERNOON WITH PERIODIC MODERATE/HEAVY SNOW POSSIBLE AT TIMES DURING THE EVENING. SUB 1SM VSBY LIKELY AT TIMES WITH 1/4-1/2SM VSBY POSSIBLE. * LAKE EFFECT SNOW SHOWERS POSSIBLE SUNDAY. * NORTH-NORTHWEST TO NORTH-NORTHEAST WINDS THROUGH THE PERIOD. MDB //DISCUSSION...UPDATED 12Z... LAST OF THE LIGHT SNOW CONTINUES TO EXIT THE TERMINALS EARLY THIS MORNING. A BAND OF IFR CIGS HAS DEVELOPED IN THE WAKE OF THE BAND BUT SHOULD BE PROGRESSING EAST AWAY FROM THE TERMINALS IN THE NEXT FEW HOURS. VARIABLE MVFR/VFR CIGS EXTEND BACK TO THE MISSISSIPPI RIVER OR SO WITH STEADIER VFR TO THE WEST. WINDS HAVE OR WILL BE TURNING NORTHERLY SHORTLY AND EXPECT THAT THERE WILL BE FLUCTUATIONS BETWEEN NW AND NNE THROUGH THE DAY. ATTENTION TURNS TO THE NEXT ROUND OF MORE SIGNIFICANT SNOW WHICH WILL ARRIVE LATER THIS AFTERNOON FROM WEST TO EAST. SNOW SHOULD QUICKLY INCREASE IN INTENSITY LATE THIS AFTERNOON AT RFD AND RIGHT AROUND 00Z IN THE CHICAGO AREA...THOUGH LIGHT SNOW MAY DEVELOP JUST PRIOR TO THAT. TIMING MAY STILL NEED SOME TWEAKING BUT HAVE GOOD CONFIDENCE OVERALL. PERIOD OF MODERATE TO EVEN BRIEFLY HEAVY SNOW ARE EXPECTED FROM LATE THIS AFTERNOON INTO MID EVENING AT RFD AND PRIMARILY DURING THE EVENING IN THE CHICAGO AREA. PREVAILING VSBY OF 1 TO 1.5SM IS LIKELY WITH PERIODS OF 1/2 TO 3/4SM VSBY POSSIBLE AS WELL. CANNOT RULE OUT SOME BRIEF PERIODS OF 1/4SM AS WELL. ACCUMULATION RATES OF 0.5 TO 1 INCH PER HOUR ARE ALSO LIKELY AT TIMES. THE MAIN FORCING FOR THE SNOW WILL PUSH SOUTHWARD FROM LATE EVENING INTO THE OVERNIGHT ALLOWING SNOW INTENSITY TO TAPER OFF AT THE TERMINALS...THOUGH SOME LIGHT SNOW MAY CONTINUE THROUGH DAYBREAK. LAKE EFFECT PROCESSES WILL THEN TRY TO TAKE OVER WHICH SHOULD LEAD TO LAKE EFFECT SNOW SHOWERS. THE CHALLENGE WILL BE DETERMINING THE LOCATION AND INTENSITY DETAILS. WITH A SLIGHT NORTHEAST WIND COMPONENT TO THE WINDS SOME OF THIS ACTIVITY MAY DRIFT TOWARD OR OVER ORD/MDW DURING THE DAY SUNDAY. SHOULD THIS OCCUR THEN PERIODIC BURSTS OF MORE INTENSE SNOW WILL BE POSSIBLE WITH GREATLY REDUCED VSBY. GYY IS PROBABLY THE MOST FAVORED FOR LAKE EFFECT ACTIVITY GIVEN THE PRIMARILY NORTH WIND BU OVERALL CONFIDENCE IS LIMITED SO CONTINUE TO MONITOR FOR THE LATEST THINKING. MDB //ORD AND MDW CONFIDENCE...UPDATED 12Z... * HIGH CONFIDENCE IN IFR CIGS IMPROVING TO VARIABLE MVFR/VFR...MEDIUM CONFIDENCE IN TIMING. MEDIUM CONFIDENCE IN CIG TRENDS FROM MID MORNING THROUGH AFTERNOON. * HIGH CONFIDENCE IN SNOW ARRIVING LATER TODAY...WITH MEDIUM-HIGH CONFIDENCE IN TIMING. LOW-MEDIUM CONFIDENCE IN WHETHER 1/2SM OR LESS VSBY OCCURS...BUT MEDIUM-HIGH CONFIDENCE THAT IT WOULD BE DURING THE EVENING IF IT DID. * LOW CONFIDENCE IN LAKE EFFECT SNOW SHOWER DETAILS SUNDAY. * HIGH CONFIDENCE IN WIND TRENDS. MDB //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...CHANCE FOR SNOW SHOWERS WITH IFR/MVFR POSSIBLE. MONDAY THROUGH FRIDAY...MAINLY VFR WITH PERIODIC LOW CHANCES FOR LIGHT SNOW. MDB && .MARINE... 302 AM CST LOW PRESSURE JUST EAST OF NORTHERN LAKE SUPERIOR WILL MOVE EASTWARD INTO WESTERN QUEBEC INTO THE EARLY AFTERNOON HOURS. A COLD FRONT IS TRAILING THIS LOW AND IS PUSHING ACROSS LAKE MICHIGAN EARLY THIS MORNING BRINGING A SHIFT TO NORTH AND NORTHWEST WINDS. SPEEDS WILL INCREASE INTO THE 15 TO 25 KT RANGE BEHIND THE FRONT THIS MORNING THEN EASE UP A BIT THIS EVENING. NORTHERLY WINDS WILL CONTINUE THROUGH SUNDAY WITH SOME CONVERGENCE LIKELY SETTING UP ACROSS CENTRAL AND SOUTHERN SECTIONS OF THE LAKE AS LAKE EFFECT PROCESSES TAKE OVER. AS THIS OCCURS AN INVERTED TROUGH WILL DEVELOP FROM SOUTHWEST TO NORTHEAST ACROSS THE OHIO VALLEY THEN SHIFT SOUTHWARD SUNDAY AND MONDAY. STRONG HIGH PRESSURE CENTERED OVER ALBERTA AND ITS ASSOCIATED RIDGE EXTENDING SOUTHEASTWARD INTO THE CENTRAL PLAINS WILL DRIFT SOUTHEAST OVER THE NEXT SEVERAL DAYS. THE RIDGE AXIS WILL RE-ORIENT SOMEWHAT AND POSITION ITSELF ACROSS THE WESTERN GREAT LAKES LATER TONIGHT...BEFORE THE HIGH BECOMES CENTERED OVER THE PLAINS AND MID AND UPPER MISSISSIPPI RIVER VALLEY LATER SUNDAY. THE PRESSURE GRADIENT LOOKS TO TIGHTEN ACROSS LAKE MICHIGAN SUNDAY NIGHT ALLOWING NORTHERLY WINDS TO INCREASE ONCE AGAIN. THE HIGH WILL MOVE EASTWARD MONDAY ALLOWING WINDS TO DROP OFF AND BECOME VARIABLE. AS THE HIGH PASSES WINDS SHIFT TO THE EAST AND SOUTHEAST FOR MID WEEK BEFORE TURNING SOUTHERLY LATE IN THE WEEK. MDB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER WEATHER ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008- ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021- ILZ022...3 PM SATURDAY TO 9 AM SUNDAY. WINTER WEATHER ADVISORY...ILZ023-ILZ032-ILZ033-ILZ039...9 PM SATURDAY TO MIDNIGHT MONDAY. IN...WINTER WEATHER ADVISORY...INZ001-INZ002-INZ010-INZ011-INZ019...9 PM SATURDAY TO MIDNIGHT MONDAY. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 510 AM CST Sat Mar 1 2014 .DISCUSSION... ISSUED 328 AM CST Sat Mar 1 2014 SHORT TERM...Today through Sunday At 08Z/2AM Arctic cold front was just entering the NW CWA accompanied by a narrow band of light snow, which has briefly dropped vsbys to 3-5 miles. Latest trends and short range models indicate what snow there is will dissipate as the front continues to shift southeast this morning. Did include low chance pops this afternoon across the northern third where models show weak omega behind front off weak dpva. As the Arctic front shifts south towards the Ohio Valley this evening, a strong 140+ kt 300mb jet sets up over the Great Lakes. This in conjunction with a tightening mid-level baroclinic zone to our south sets up good moisture transport into a region of strong frontogenesis over Iowa and northern IL. As this zone gradually shifts south this evening, expect snow to increase in coverage and intensity. Given the strength of projected frontogenesis and a hint of negative EPV above this zone would expect some banding and enhance snowfall rates overnight. 00Z guidance has trended more progressive the the band of stronger forcing, shifting this south of I-72 Sunday morning. This seems reasonable given the fact this is an open wave at 850/700 mb. Snow will likely continue over the southern half Sunday afternoon, and into Sunday night far SE, as additional shortwave energy ejects from southern plains trough. Thermal profiles off consistent GFS/ECMWF show snow for much of the CWA, except south of I-70 where a sleet/freezing rain mix is possible for several hours after onset. Have discounted aggressive warmer NAM thermal structure (which would bring mixed precip north of I-72) due to open wave feature. This does lead to lower overall confidence in p-type than would be desired at 24 hrs. Given precipitable water values 0.6-0.9 and projected forcing, model qpf raning from 0.3 NW to 0.75 SE looks reasonable. Used 12:1 snow:liquid ratio, except 10:1 south of I-70 due to thermal profiles. For the northwest half of the CWA projected totals of 4-6" in 18+ hours fall short of warning criteria (6"+ in 12 hours or 8"+ in 24 hours) and have issued winter wx advisory for 6 PM tonight through 6 PM Sunday. For areas southeast of a Shebyville to Monticello to Rantoul line, 5-8" forecast over a 24+ hour period also falls short of warning criteria. The potential for mixed precip does complicate things, as warning sleet/ice accums would be possible under NAM solution. With uncertaininty remaning in this area will keep winter storm watch going (midnight tonight through 6 AM Monday morning), and let day shift make the call after looking over 12Z data. LONG TERM...Monday through Friday Bitterly cold air moves into the region behind the departing storm. Late season Arctic high pressure will produce temps 20-25 degrees below normal, with lows likely dropping below zero across the north Monday and Tuesday mornings. A weak shortwave dropping through in northwest flow behind the high, will bring a chance of light snow to the northern half of the CWA Tuesday. With low moisture availablity have kept pops to slight chance. While temps will remain below normal through the week, readings will gradually moderate as mid level flow flattens. Dry weather is expected as split flow keeps major systems well to our north and south. 25 && .AVIATION... ISSUED 510 AM CST Sat Mar 1 2014 IFR CIGs behind cold front beginning to work into central Illinois from the northwest. KGBG has dropped to OVC007 and large area of CIGs between 007 and 012 extends approximately 100 nm behind the cold front. Although diurnal influence may raise the CIGs slightly as they work southeast, latest HRRR suggest the band will hold together much of the day. Have translated the IFR/MVFR clouds into the terminals this morning as front pushes through. So far only minor reductions in VSBYs and will leave as P6SM for now. Jet streak induced broad area of snow is expected to develop across the upper Mississippi Valley this afternoon and advect southward into the terminals this evening. Will likely be occasional VSBYs lower, will currently broadbrush with 2 nm. As the area develops later packages can hone the details on exactly when LIFR VSBYs might occur. Barker && .ILX WATCHES/WARNINGS/ADVISORIES... WINTER STORM WATCH from late tonight through late Sunday night FOR ILZ044>046-054>057-061>063-066>068-071>073. WINTER WEATHER ADVISORY from 6 PM this evening to 6 PM CST Sunday FOR ILZ027>031-036>038-040>043-047>053. && $$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
102 PM MST SAT MAR 1 2014 .SHORT TERM...(TODAY THROUGH MONDAY NIGHT) ISSUED AT 419 AM MST SAT MAR 1 2014 MAIN FORECAST CONCERNS...AMONG VERY MANY...WILL BE PHASE OF PRECIPITATION AND AMOUNT OF ICE AND SNOW ACCUMULATION INTO TOMORROW SATELLITE CONTINUING TO SHOW AN AMPLIFIED/COMPLEX AND EVEN RETROGRESSIVE PATTERN FROM THE PACIFIC INTO CANADA. HIGH AMPLITUDE RIDGE RESIDES ALONG THE WEST COAST OF NORTH AMERICA WITH BROAD AND COLD UPPER TROUGH OVER CANADA. WEAKENING/FILLING SYSTEM IS MOVING TOWARD THE CALIFORNIA COAST WITH A LARGE AMOUNT OF MID AND UPPER LEVEL MOISTURE STREAMING OUT AHEAD OF IT. A SIGNIFICANT LOBE ROTATING AROUND THE CANADIAN TROUGH IS PUSHING SOUTH. AT JET LEVEL...MODELS INITIALIZED POORLY WITH JET SEGMENT IN ADVANCE OF SYSTEM OFF THE CALIFORNIA COAST. THE UKMET AND NAM WERE DOING THE BEST BUT WERE STILL OFF. AT MID LEVELS...THE GFS...ECMWF ...CANADIAN AND SREF WERE DOING ABOUT THE SAME AND THE BEST OF THE AVAILABLE OUTPUT. THE ECMWF WAS DOING A LITTLE BETTER THAN THE SREF ON THE SURFACE WIND AND PRESSURE FIELD. THE UKMET...GFS...NAM AND CANADIAN WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD. EVEN THOUGH THEY ARE NOT PRODUCING A LOT OF QPF...THEY ARE TENDING TO OVERDO IT WITH THE GFS...NAM...AND SREF THE WORST. THIS WILL CONTINUE TO BE A VERY LOW CONFIDENCE FORECAST DUE TO POOR INITIAL ANALYSIS ON MID AND UPPER LEVEL FEATURES...MODEL DIFFERENCES IN THERMAL AND MOISTURE PROFILES...AND MODELS CHANGING FROM THEIR SOLUTIONS...SOMETIMES DRAMATICALLY...FROM 24 HOURS AGO. SAYING ALL THAT...THE WINTER WEATHER ADVISORY DOES STILL LOOK ON TRACK DUE TO THE VARIABLE PHASES...VARIABLE ICE AND SNOW AMOUNTS. IN GENERAL DID INCREASE ICE AMOUNTS...STILL BELOW A TENTH OF AN INCH...DUE TO A LONGER TIME FOR ICE ACCUMULATION...AND LOWERED SNOW AMOUNTS SLIGHTLY DUE TO NOT VERY MUCH SNOW ACCUMULATION UNTIL TONIGHT. TODAY/TONIGHT...JET SETUP BY THE END OF THE DAY IS DIFFERENT THAN WHAT WAS DEPICTED YESTERDAY. BY LATE IN THE DAY THE MAIN JET SEGMENT IS STILL TO THE WEST OF MY AREA WITH THE RIGHT FRONT QUADRANT OVER THE AREA. SO AT FIRST GLANCE THERE DOES NOT APPEAR TO BE A LOT TO DRIVE PRECIPITATION DEVELOPMENT DUE TO ANY STRONG FEATURES. HOWEVER...MODELS DO CONTINUE TO PRODUCE LIGHT AMOUNTS OF QPF. THE LIFT IS BEING GENERATED BY LOW LEVEL UPSLOPE AND ISENTROPIC LIFT ABOVE THIS DOME OF COLD AIR. PRECIPITATION HAS BEEN SLOWER TO START THAN WHAT WAS PREVIOUSLY EXPECTED. SURFACE OBSERVATIONS ARE STARTING TO SHOW SOME PRECIPITATION. SO BELIEVE WILL HAVE LIGHT PRECIPITATION AROUND FOR MOST OF THE DAY. SO QUESTION BECOMES PHASE. 00Z SOUNDINGS SHOW EITHER A DRY AIR MASS OR ONLY A SATURATED SHALLOW AIR MASS AND THAT WAS EVIDENT IN SOME FOG DEVELOPMENT WHICH I WILL ADD. GFS HAS CHANGED ITS TUNE FROM YESTERDAY. IT IS NOT AS AGGRESSIVE IN SATURATING THE COLUMN TO A DEEPER DEPTH. THE NAM ALSO CHANGED ITS TUNE AND SATURATED TO GREATER DEPTH...AT LEAST IN THE BEGINNING...IN A SIMILAR FASHION AS THE GFS WHICH IS SLIGHTLY DRIER ALOFT THAN THE NAM. WARM LAYER APPEARS IN ALL AREAS OR ALMOST ALL AREAS AT THE BEGINNING WITH THE GFS SHOWING WARMER TEMPERATURES ALOFT. NORTHERN AREAS SHOULD SEE ALL SNOW ONLY BECAUSE THE DENDRITIC ZONE IS AT THE SURFACE. FOR A FEW COUNTIES SOUTH AND WEST OF THAT A MIXTURE OF FREEZING DRIZZLE...SNOW AND SLEET IS INDICATED WITH THE FAR SOUTH AND WEST INDICATING SLEET AND FREEZING DRIZZLE. THIS AREA WORKS ITS WAY SOUTH GRADUALLY THROUGH THE DAY. ALL IN ALL THE PREVIOUS FORECAST HAD THE POP AND PHASE LAYOUT IN GOOD SHAPE AND ONLY MADE MINOR ADJUSTMENTS. WITH NOT VERY STRONG LIFT...DID REDUCE THE ALREADY LIGHT SNOW AMOUNTS A LITTLE. RIGHT REAR QUADRANT OF THE JET MOVES ACROSS THE AREA DURING THE NIGHT. AT THE SAME A SHORTWAVE TROUGH MOVES ACROSS THE AREA WITH ISENTROPIC LIFT STILL IN PLACE. GFS CONTINUES TO NOT HAVE A DEEP OF A SATURATED LAYER AS YESTERDAY. HOWEVER...THE DENDRITIC ZONE REMAINS NEAR OR AT THE SURFACE. WHAT IS ALSO DIFFERENT FROM YESTERDAY IS THAT THE GFS IS DOING WHAT THE NAM WAS DOING YESTERDAY WHICH IS KEEPING A MIXTURE IN PLACE FOR MUCH LONGER. IF SOUNDINGS ARE CORRECT THE FAR SOUTH AND WEST MAY NOT DO A COMPLETE CHANGE OVER TO SNOW UNTIL AFTER MIDNIGHT. AM CONCERNED THAT THE MODELS MAY BE UNDERDOING PRECIPITATION/SNOW AMOUNTS DUE TO THE STRONG LIFT FROM THE JET/UPPER DEFORMATION MOVING ACROSS. BY MIDNIGHT THE MAIN AREA OF SNOW WILL HAVE MOVED INTO THE SOUTHEAST HALF AND THAT IS WHERE WE WILL HAVE TO WATCH AMOUNTS CAREFULLY. FOR MAXES...MODEL GUIDANCE IS WARMER AND THAT LOOKS TO BE MAINLY DUE TO THE MODELS NOT COOLING OFF TEMPERATURES AS MUCH FOR THIS MORNING. MAXES MAY BE EARLY. USED A COMBINATION OF HRRR AND MAV TO ADJUST THE MAXES. KEPT MINS WARMER AND ABOVE THE COLDEST GUIDANCE DUE TO THE CLOUDS AND UPSLOPE WINDS. CONSEQUENTLY THE WIND CHILL READINGS ARE NOT AS LOW AS PREVIOUS FEW DAYS WITH MARGINAL WIND CHILL ADVISORY CRITERIA ALONG AND EAST OF THE COLORADO BORDER. SUNDAY/SUNDAY NIGHT...MODELS DIFFERING ON THE SPEED/POSITION A LITTLE BUT IN GENERAL THEY SHOW THE RIGHT REAR QUADRANT AFFECTING THE SOUTHEAST HALF OF THE AREA AT THE BEGINNING OF THE DAY. THIS IS TO THE EAST OF THE AREA BY 18Z. IT IS ALSO BY THIS TIME THAT DOWNGLIDE IS OCCURRING ON 290 SURFACE. PRECIPITATION BE HIGHEST IN THE SOUTHEAST HALF OF THE FORECAST AREA DUE TO THE JET AND SHORTWAVE TROUGH. SO KEPT HIGHER POPS THERE AND LOWERED THEM OVER THE REST OF THE AREA. SNOW WILL GRADUALLY DECREASE DURING THE DAY WITH FLURRIES EXPECTED DURING THE EVENING. BASED ON SATURATED LOW LEVELS DID TOSS IN SOME PATCHY FREEZING FOG DURING THE OVERNIGHT HOURS. CLOUDS...UPSLOPE WINDS AND COLD AIR ADVECTION WILL BE PLACE FOR THE ENTIRE DAY. NOT SURE WHY MODEL GUIDANCE IS WARMING UP MAXES SO MUCH. KEPT THE MAXES NEAR THE COLDER SIDE AND NEAR THE BETTER PERFORMING GUIDANCE. MINS WILL BE WARMER THAN THE PREVIOUS NIGHT WHICH AGAIN MEANS WIND CHILL READINGS NOT GETTING AS COLD. AGAIN REACHING MARGINAL ADVISORY VALUES. MONDAY/MONDAY NIGHT...WEAK RIGHT REAR QUADRANT OF THE JET DEVELOPS OVER THE AREA BY THE MIDDLE OF THE DAY AND AFFECTS THE AREA AT LEAST THROUGH THE EVENING. THERE WILL BE A DEEP DRY LAYER SO ONLY CLOUDS WILL RESULT. SO THIS PERIOD WILL JUST END UP BEING A TEMPERATURE FORECAST. DEPENDING ON HOW MUCH SNOW FALLS AND WHERE... THAT COULD CAUSE IN THE TEMPERATURE LAYOUT I HAVE IN THERE. MODELS ARE BRINGING IN WARMER AIR FURTHER EAST AND FOR THE MOST PART I BELIEVE THEY ARE TOO AGGRESSIVE. SINCE THE ECMWF HAS A BETTER DEPICTION OF THE SURFACE...DO LIKE ITS TEMPERATURES A LITTLE BETTER. HOWEVER...MODELS HAVE HAD A TENDENCY TO HOLD TO COLD TEMPERATURES TOO LONG IN THIS PATTERN WHICH BECOMES STRONG ZONAL. WARM AIR ADVECTION PATTERN DEVELOPS IN ERNEST DURING THE NIGHT AND MAY END UP HAVING WARMING TEMPERATURES DURING THE OVERNIGHT HOURS. .LONG TERM...(TOMORROW NIGHT THROUGH NEXT SATURDAY) ISSUED AT 1248 PM MST SAT MAR 1 2014 RIDGING WILL GENERALLY BE IN PLACE OVER THE CENTRAL ROCKIES LEADING TO NORTHWEST FLOW OVER THE CENTRAL PLAINS THROUGH THE PERIOD. A SERIES OF EMBEDDED SHORTWAVE TROUGHS WILL BRING OCCASIONAL CHANCES FOR LIGHT PRECIPITATION LATER IN THE MID TO LATE WEEK TIMEFRAME. TEMPERATURES WILL START OUT BELOW NORMAL TO START BUT THE ARCTIC AIR WILL QUICKLY RETREAT AND FROM TUESDAY AND BEYOND TEMPERATURES WILL BE ABOVE NORMAL UNDER THE INFLUENCE OF THE RIDGE. AS FOR PRECIPITATION...MONDAY AND TUESDAY WILL BE DRY. SHORTWAVE TROUGH COMING OVER THE RIDGE TUESDAY NIGHT WILL BRING LOW CHANCES OF LIGHT PRECIPITATION WITH MAIN ENERGY GOING SOUTH. FORECAST POINT SOUNDINGS SHOW DRY AIR IN THE MID LEVELS AND MOST PRECIPITATION WILL PROBABLY NOT MAKE IT TO THE GROUND. A SUFFICIENT WARM LAYER WILL EXIST TO MELT ANY ICE...SO PRECIPITATION TYPE WILL BE DETERMINED BY SURFACE TEMPERATURES WHICH WILL BE IN THE LOWER TO MIDDLE 30S. WILL CARRY SLIGHT CHANCES OF -RA/-FZRA WITH LOW CONFIDENCE EITHER WILL PAN OUT. THAT SCENARIO CARRIES OVER INTO WEDNESDAY MORNING...THEN A CHANCE OF RAIN WEDNESDAY AFTERNOON SURFACE TEMPERATURES WARM. SHORTWAVE RIDGING WILL KEEP IT DRY WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. NEXT SHORTWAVE TROUGH ARRIVES ON FRIDAY. MOISTURE LOOKS BETTER IN DENDRITIC LAYER BUT SURFACE WILL BE WARM TO START. COLDER AIR ARRIVES FRIDAY AFTERNOON WITH COLD FRONT. GIVEN THERE WILL BE ICE IN THE COLUMN BUT UNCERTAINTY ON EXTENT OF SURFACE BASED WARM LAYER WILL CARRY RAIN/SNOW AS PRECIPITATION TYPE THROUGH FRIDAY NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1103 AM MST SAT MAR 1 2014 IFR CONDITIONS SHOULD CONTINUE THROUGH AT LEAST THIS EVENING AT KGLD AND KMCK. CEILINGS WILL LIKELY REMAIN IN THE MVFR CATEGORY BUT LIGHT SNOW IS CAUSING VISIBILITY REDUCTIONS TO IFR. EARLIER THIS MORNING KGLD DROPPED BRIEFLY TO LIFR DUE TO 3/4 SM VISIBILITY BUT SNOW INTENSITY IS EXPECTED TO REMAIN LIGHT ENOUGH THAT VISIBILITY REMAINS IN THE IFR CATEGORY. IF A PERIOD OF GREATER SNOW INTENSITIES AT EITHER TERMINAL WERE TO OCCUR CAUSING A REDUCTION IN VISIBILITY TO LIFR...IT WOULD LIKELY BE DURING THE EVENING WHEN SHORT TERM MODEL GUIDANCE SUGGEST SLIGHTLY STRONGER FRONTOGENESIS/LIFT MAY BE PRESENT. OTHERWISE EXPECT FLUCTUATIONS IN VISIBILITY TO CONTINUE FROM AROUND 1 SM TO AROUND 3 SM. TOWARD TOMORROW MORNING...MOISTURE BECOMES SHALLOWER AND SNOW INTENSITIES SHOULD DECREASE SUFFICIENTLY FOR MVFR CONDITIONS. SOME LIGHT FREEZING DRIZZLE HAS OCCASIONALLY BEEN MIXED IN WITH THE SNOW BUT ICE ACCUMULATION HAS BEEN VERY MINOR TO NON-EXISTENT. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...WINTER WEATHER ADVISORY UNTIL 5 PM MST /6 PM CST/ SUNDAY FOR KSZ001>004-013>016-027>029-041-042. CO...WINTER WEATHER ADVISORY UNTIL 5 PM MST SUNDAY FOR COZ090>092. NE...WINTER WEATHER ADVISORY UNTIL 5 PM MST /6 PM CST/ SUNDAY FOR NEZ079>081. && $$ SHORT TERM...BULLER LONG TERM...024 AVIATION...BRB
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1103 AM MST SAT MAR 1 2014 .SHORT TERM...(TODAY THROUGH MONDAY NIGHT) ISSUED AT 419 AM MST SAT MAR 1 2014 MAIN FORECAST CONCERNS...AMONG VERY MANY...WILL BE PHASE OF PRECIPITATION AND AMOUNT OF ICE AND SNOW ACCUMULATION INTO TOMORROW SATELLITE CONTINUING TO SHOW AN AMPLIFIED/COMPLEX AND EVEN RETROGRESSIVE PATTERN FROM THE PACIFIC INTO CANADA. HIGH AMPLITUDE RIDGE RESIDES ALONG THE WEST COAST OF NORTH AMERICA WITH BROAD AND COLD UPPER TROUGH OVER CANADA. WEAKENING/FILLING SYSTEM IS MOVING TOWARD THE CALIFORNIA COAST WITH A LARGE AMOUNT OF MID AND UPPER LEVEL MOISTURE STREAMING OUT AHEAD OF IT. A SIGNIFICANT LOBE ROTATING AROUND THE CANADIAN TROUGH IS PUSHING SOUTH. AT JET LEVEL...MODELS INITIALIZED POORLY WITH JET SEGMENT IN ADVANCE OF SYSTEM OFF THE CALIFORNIA COAST. THE UKMET AND NAM WERE DOING THE BEST BUT WERE STILL OFF. AT MID LEVELS...THE GFS...ECMWF ...CANADIAN AND SREF WERE DOING ABOUT THE SAME AND THE BEST OF THE AVAILABLE OUTPUT. THE ECMWF WAS DOING A LITTLE BETTER THAN THE SREF ON THE SURFACE WIND AND PRESSURE FIELD. THE UKMET...GFS...NAM AND CANADIAN WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD. EVEN THOUGH THEY ARE NOT PRODUCING A LOT OF QPF...THEY ARE TENDING TO OVERDO IT WITH THE GFS...NAM...AND SREF THE WORST. THIS WILL CONTINUE TO BE A VERY LOW CONFIDENCE FORECAST DUE TO POOR INITIAL ANALYSIS ON MID AND UPPER LEVEL FEATURES...MODEL DIFFERENCES IN THERMAL AND MOISTURE PROFILES...AND MODELS CHANGING FROM THEIR SOLUTIONS...SOMETIMES DRAMATICALLY...FROM 24 HOURS AGO. SAYING ALL THAT...THE WINTER WEATHER ADVISORY DOES STILL LOOK ON TRACK DUE TO THE VARIABLE PHASES...VARIABLE ICE AND SNOW AMOUNTS. IN GENERAL DID INCREASE ICE AMOUNTS...STILL BELOW A TENTH OF AN INCH...DUE TO A LONGER TIME FOR ICE ACCUMULATION...AND LOWERED SNOW AMOUNTS SLIGHTLY DUE TO NOT VERY MUCH SNOW ACCUMULATION UNTIL TONIGHT. TODAY/TONIGHT...JET SETUP BY THE END OF THE DAY IS DIFFERENT THAN WHAT WAS DEPICTED YESTERDAY. BY LATE IN THE DAY THE MAIN JET SEGMENT IS STILL TO THE WEST OF MY AREA WITH THE RIGHT FRONT QUADRANT OVER THE AREA. SO AT FIRST GLANCE THERE DOES NOT APPEAR TO BE A LOT TO DRIVE PRECIPITATION DEVELOPMENT DUE TO ANY STRONG FEATURES. HOWEVER...MODELS DO CONTINUE TO PRODUCE LIGHT AMOUNTS OF QPF. THE LIFT IS BEING GENERATED BY LOW LEVEL UPSLOPE AND ISENTROPIC LIFT ABOVE THIS DOME OF COLD AIR. PRECIPITATION HAS BEEN SLOWER TO START THAN WHAT WAS PREVIOUSLY EXPECTED. SURFACE OBSERVATIONS ARE STARTING TO SHOW SOME PRECIPITATION. SO BELIEVE WILL HAVE LIGHT PRECIPITATION AROUND FOR MOST OF THE DAY. SO QUESTION BECOMES PHASE. 00Z SOUNDINGS SHOW EITHER A DRY AIR MASS OR ONLY A SATURATED SHALLOW AIR MASS AND THAT WAS EVIDENT IN SOME FOG DEVELOPMENT WHICH I WILL ADD. GFS HAS CHANGED ITS TUNE FROM YESTERDAY. IT IS NOT AS AGGRESSIVE IN SATURATING THE COLUMN TO A DEEPER DEPTH. THE NAM ALSO CHANGED ITS TUNE AND SATURATED TO GREATER DEPTH...AT LEAST IN THE BEGINNING...IN A SIMILAR FASHION AS THE GFS WHICH IS SLIGHTLY DRIER ALOFT THAN THE NAM. WARM LAYER APPEARS IN ALL AREAS OR ALMOST ALL AREAS AT THE BEGINNING WITH THE GFS SHOWING WARMER TEMPERATURES ALOFT. NORTHERN AREAS SHOULD SEE ALL SNOW ONLY BECAUSE THE DENDRITIC ZONE IS AT THE SURFACE. FOR A FEW COUNTIES SOUTH AND WEST OF THAT A MIXTURE OF FREEZING DRIZZLE...SNOW AND SLEET IS INDICATED WITH THE FAR SOUTH AND WEST INDICATING SLEET AND FREEZING DRIZZLE. THIS AREA WORKS ITS WAY SOUTH GRADUALLY THROUGH THE DAY. ALL IN ALL THE PREVIOUS FORECAST HAD THE POP AND PHASE LAYOUT IN GOOD SHAPE AND ONLY MADE MINOR ADJUSTMENTS. WITH NOT VERY STRONG LIFT...DID REDUCE THE ALREADY LIGHT SNOW AMOUNTS A LITTLE. RIGHT REAR QUADRANT OF THE JET MOVES ACROSS THE AREA DURING THE NIGHT. AT THE SAME A SHORTWAVE TROUGH MOVES ACROSS THE AREA WITH ISENTROPIC LIFT STILL IN PLACE. GFS CONTINUES TO NOT HAVE A DEEP OF A SATURATED LAYER AS YESTERDAY. HOWEVER...THE DENDRITIC ZONE REMAINS NEAR OR AT THE SURFACE. WHAT IS ALSO DIFFERENT FROM YESTERDAY IS THAT THE GFS IS DOING WHAT THE NAM WAS DOING YESTERDAY WHICH IS KEEPING A MIXTURE IN PLACE FOR MUCH LONGER. IF SOUNDINGS ARE CORRECT THE FAR SOUTH AND WEST MAY NOT DO A COMPLETE CHANGE OVER TO SNOW UNTIL AFTER MIDNIGHT. AM CONCERNED THAT THE MODELS MAY BE UNDERDOING PRECIPITATION/SNOW AMOUNTS DUE TO THE STRONG LIFT FROM THE JET/UPPER DEFORMATION MOVING ACROSS. BY MIDNIGHT THE MAIN AREA OF SNOW WILL HAVE MOVED INTO THE SOUTHEAST HALF AND THAT IS WHERE WE WILL HAVE TO WATCH AMOUNTS CAREFULLY. FOR MAXES...MODEL GUIDANCE IS WARMER AND THAT LOOKS TO BE MAINLY DUE TO THE MODELS NOT COOLING OFF TEMPERATURES AS MUCH FOR THIS MORNING. MAXES MAY BE EARLY. USED A COMBINATION OF HRRR AND MAV TO ADJUST THE MAXES. KEPT MINS WARMER AND ABOVE THE COLDEST GUIDANCE DUE TO THE CLOUDS AND UPSLOPE WINDS. CONSEQUENTLY THE WIND CHILL READINGS ARE NOT AS LOW AS PREVIOUS FEW DAYS WITH MARGINAL WIND CHILL ADVISORY CRITERIA ALONG AND EAST OF THE COLORADO BORDER. SUNDAY/SUNDAY NIGHT...MODELS DIFFERING ON THE SPEED/POSITION A LITTLE BUT IN GENERAL THEY SHOW THE RIGHT REAR QUADRANT AFFECTING THE SOUTHEAST HALF OF THE AREA AT THE BEGINNING OF THE DAY. THIS IS TO THE EAST OF THE AREA BY 18Z. IT IS ALSO BY THIS TIME THAT DOWNGLIDE IS OCCURRING ON 290 SURFACE. PRECIPITATION BE HIGHEST IN THE SOUTHEAST HALF OF THE FORECAST AREA DUE TO THE JET AND SHORTWAVE TROUGH. SO KEPT HIGHER POPS THERE AND LOWERED THEM OVER THE REST OF THE AREA. SNOW WILL GRADUALLY DECREASE DURING THE DAY WITH FLURRIES EXPECTED DURING THE EVENING. BASED ON SATURATED LOW LEVELS DID TOSS IN SOME PATCHY FREEZING FOG DURING THE OVERNIGHT HOURS. CLOUDS...UPSLOPE WINDS AND COLD AIR ADVECTION WILL BE PLACE FOR THE ENTIRE DAY. NOT SURE WHY MODEL GUIDANCE IS WARMING UP MAXES SO MUCH. KEPT THE MAXES NEAR THE COLDER SIDE AND NEAR THE BETTER PERFORMING GUIDANCE. MINS WILL BE WARMER THAN THE PREVIOUS NIGHT WHICH AGAIN MEANS WIND CHILL READINGS NOT GETTING AS COLD. AGAIN REACHING MARGINAL ADVISORY VALUES. MONDAY/MONDAY NIGHT...WEAK RIGHT REAR QUADRANT OF THE JET DEVELOPS OVER THE AREA BY THE MIDDLE OF THE DAY AND AFFECTS THE AREA AT LEAST THROUGH THE EVENING. THERE WILL BE A DEEP DRY LAYER SO ONLY CLOUDS WILL RESULT. SO THIS PERIOD WILL JUST END UP BEING A TEMPERATURE FORECAST. DEPENDING ON HOW MUCH SNOW FALLS AND WHERE... THAT COULD CAUSE IN THE TEMPERATURE LAYOUT I HAVE IN THERE. MODELS ARE BRINGING IN WARMER AIR FURTHER EAST AND FOR THE MOST PART I BELIEVE THEY ARE TOO AGGRESSIVE. SINCE THE ECMWF HAS A BETTER DEPICTION OF THE SURFACE...DO LIKE ITS TEMPERATURES A LITTLE BETTER. HOWEVER...MODELS HAVE HAD A TENDENCY TO HOLD TO COLD TEMPERATURES TOO LONG IN THIS PATTERN WHICH BECOMES STRONG ZONAL. WARM AIR ADVECTION PATTERN DEVELOPS IN ERNEST DURING THE NIGHT AND MAY END UP HAVING WARMING TEMPERATURES DURING THE OVERNIGHT HOURS. .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 419 AM MST SAT MAR 1 2014 NEAR TO ABOVE NORMAL TEMPERATURES WILL START OUT THIS PERIOD AS THE COLD FRONT FROM THE WEEKEND CONTINUES TO MOVE EAST OUT OF THE AREA. THE NEXT CHANCE FOR PRECIPITATION WILL BE WEDNESDAY AS AN UPPER LEVEL SHORT WAVE TROUGH MOVES ACROSS THE AREA BRINGING A BRIEF SHOT FOR SOME RAIN/SNOW. TEMPERATURES CONTINUE TO WARM THURSDAY AS A SHORT WAVE RIDGE BUILDS OVER THE AREA. HIGHS WILL BE IN THE 60S AND LOWS WILL BE IN THE 30S. FRIDAY ANOTHER STRONGER UPPER LEVEL SHORT WAVE TROUGH MOVES OVER THE AREA...REMAINING OVER THE AREA UNTIL SATURDAY. LATE FRIDAY AFTERNOON AND FRIDAY EVENING A COLD FRONT WILL MOVE THROUGH THE AREA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1103 AM MST SAT MAR 1 2014 IFR CONDITIONS SHOULD CONTINUE THROUGH AT LEAST THIS EVENING AT KGLD AND KMCK. CEILINGS WILL LIKELY REMAIN IN THE MVFR CATEGORY BUT LIGHT SNOW IS CAUSING VISIBILITY REDUCTIONS TO IFR. EARLIER THIS MORNING KGLD DROPPED BRIEFLY TO LIFR DUE TO 3/4 SM VISIBILITY BUT SNOW INTENSITY IS EXPECTED TO REMAIN LIGHT ENOUGH THAT VISIBILITY REMAINS IN THE IFR CATEGORY. IF A PERIOD OF GREATER SNOW INTENSITIES AT EITHER TERMINAL WERE TO OCCUR CAUSING A REDUCTION IN VISIBILITY TO LIFR...IT WOULD LIKELY BE DURING THE EVENING WHEN SHORT TERM MODEL GUIDANCE SUGGEST SLIGHTLY STRONGER FRONTOGENESIS/LIFT MAY BE PRESENT. OTHERWISE EXPECT FLUCTIATIONS IN VISIBILITY TO CONTINUE FROM AROUND 1 SM TO AROUND 3 SM. TOWARD TOMORROW MORNING...MOISTURE BECOMES SHALLOWER AND SNOW INTENSITIES SHOULD DECREASE SUFFICIENTLY FOR MVFR CONDITIONS. SOME LIGHT FREEZING DRIZZLE HAS OCCASIONALLY BEEN MIXED IN WITH THE SNOW BUT ICE ACCUMULATION HAS BEEN VERY MINOR TO NON-EXISTIENT. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...WINTER WEATHER ADVISORY UNTIL 5 PM MST /6 PM CST/ SUNDAY FOR KSZ001>004-013>016-027>029-041-042. CO...WINTER WEATHER ADVISORY UNTIL 5 PM MST SUNDAY FOR COZ090>092. NE...WINTER WEATHER ADVISORY UNTIL 5 PM MST /6 PM CST/ SUNDAY FOR NEZ079>081. && $$ SHORT TERM...BULLER LONG TERM...JTL AVIATION...BRB
AREA FORECAST DISCUSSION
NWS GOODLAND KS
518 AM MST SAT MAR 1 2014 .SHORT TERM...(TODAY THROUGH MONDAY NIGHT) ISSUED AT 419 AM MST SAT MAR 1 2014 MAIN FORECAST CONCERNS...AMONG VERY MANY...WILL BE PHASE OF PRECIPITATION AND AMOUNT OF ICE AND SNOW ACCUMULATION INTO TOMORROW SATELLITE CONTINUING TO SHOW AN AMPLIFIED/COMPLEX AND EVEN RETROGRESSIVE PATTERN FROM THE PACIFIC INTO CANADA. HIGH AMPLITUDE RIDGE RESIDES ALONG THE WEST COAST OF NORTH AMERICA WITH BROAD AND COLD UPPER TROUGH OVER CANADA. WEAKENING/FILLING SYSTEM IS MOVING TOWARD THE CALIFORNIA COAST WITH A LARGE AMOUNT OF MID AND UPPER LEVEL MOISTURE STREAMING OUT AHEAD OF IT. A SIGNIFICANT LOBE ROTATING AROUND THE CANADIAN TROUGH IS PUSHING SOUTH. AT JET LEVEL...MODELS INITIALIZED POORLY WITH JET SEGMENT IN ADVANCE OF SYSTEM OFF THE CALIFORNIA COAST. THE UKMET AND NAM WERE DOING THE BEST BUT WERE STILL OFF. AT MID LEVELS...THE GFS...ECMWF ...CANADIAN AND SREF WERE DOING ABOUT THE SAME AND THE BEST OF THE AVAILABLE OUTPUT. THE ECMWF WAS DOING A LITTLE BETTER THAN THE SREF ON THE SURFACE WIND AND PRESSURE FIELD. THE UKMET...GFS...NAM AND CANADIAN WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD. EVEN THOUGH THEY ARE NOT PRODUCING A LOT OF QPF...THEY ARE TENDING TO OVERDO IT WITH THE GFS...NAM...AND SREF THE WORST. THIS WILL CONTINUE TO BE A VERY LOW CONFIDENCE FORECAST DUE TO POOR INITIAL ANALYSIS ON MID AND UPPER LEVEL FEATURES...MODEL DIFFERENCES IN THERMAL AND MOISTURE PROFILES...AND MODELS CHANGING FROM THEIR SOLUTIONS...SOMETIMES DRAMATICALLY...FROM 24 HOURS AGO. SAYING ALL THAT...THE WINTER WEATHER ADVISORY DOES STILL LOOK ON TRACK DUE TO THE VARIABLE PHASES...VARIABLE ICE AND SNOW AMOUNTS. IN GENERAL DID INCREASE ICE AMOUNTS...STILL BELOW A TENTH OF AN INCH...DUE TO A LONGER TIME FOR ICE ACCUMULATION...AND LOWERED SNOW AMOUNTS SLIGHTLY DUE TO NOT VERY MUCH SNOW ACCUMULATION UNTIL TONIGHT. TODAY/TONIGHT...JET SETUP BY THE END OF THE DAY IS DIFFERENT THAN WHAT WAS DEPICTED YESTERDAY. BY LATE IN THE DAY THE MAIN JET SEGMENT IS STILL TO THE WEST OF MY AREA WITH THE RIGHT FRONT QUADRANT OVER THE AREA. SO AT FIRST GLANCE THERE DOES NOT APPEAR TO BE A LOT TO DRIVE PRECIPITATION DEVELOPMENT DUE TO ANY STRONG FEATURES. HOWEVER...MODELS DO CONTINUE TO PRODUCE LIGHT AMOUNTS OF QPF. THE LIFT IS BEING GENERATED BY LOW LEVEL UPSLOPE AND ISENTROPIC LIFT ABOVE THIS DOME OF COLD AIR. PRECIPITATION HAS BEEN SLOWER TO START THAN WHAT WAS PREVIOUSLY EXPECTED. SURFACE OBSERVATIONS ARE STARTING TO SHOW SOME PRECIPITATION. SO BELIEVE WILL HAVE LIGHT PRECIPITATION AROUND FOR MOST OF THE DAY. SO QUESTION BECOMES PHASE. 00Z SOUNDINGS SHOW EITHER A DRY AIR MASS OR ONLY A SATURATED SHALLOW AIR MASS AND THAT WAS EVIDENT IN SOME FOG DEVELOPMENT WHICH I WILL ADD. GFS HAS CHANGED ITS TUNE FROM YESTERDAY. IT IS NOT AS AGGRESSIVE IN SATURATING THE COLUMN TO A DEEPER DEPTH. THE NAM ALSO CHANGED ITS TUNE AND SATURATED TO GREATER DEPTH...AT LEAST IN THE BEGINNING...IN A SIMILAR FASHION AS THE GFS WHICH IS SLIGHTLY DRIER ALOFT THAN THE NAM. WARM LAYER APPEARS IN ALL AREAS OR ALMOST ALL AREAS AT THE BEGINNING WITH THE GFS SHOWING WARMER TEMPERATURES ALOFT. NORTHERN AREAS SHOULD SEE ALL SNOW ONLY BECAUSE THE DENDRITIC ZONE IS AT THE SURFACE. FOR A FEW COUNTIES SOUTH AND WEST OF THAT A MIXTURE OF FREEZING DRIZZLE...SNOW AND SLEET IS INDICATED WITH THE FAR SOUTH AND WEST INDICATING SLEET AND FREEZING DRIZZLE. THIS AREA WORKS ITS WAY SOUTH GRADUALLY THROUGH THE DAY. ALL IN ALL THE PREVIOUS FORECAST HAD THE POP AND PHASE LAYOUT IN GOOD SHAPE AND ONLY MADE MINOR ADJUSTMENTS. WITH NOT VERY STRONG LIFT...DID REDUCE THE ALREADY LIGHT SNOW AMOUNTS A LITTLE. RIGHT REAR QUADRANT OF THE JET MOVES ACROSS THE AREA DURING THE NIGHT. AT THE SAME A SHORTWAVE TROUGH MOVES ACROSS THE AREA WITH ISENTROPIC LIFT STILL IN PLACE. GFS CONTINUES TO NOT HAVE A DEEP OF A SATURATED LAYER AS YESTERDAY. HOWEVER...THE DENDRITIC ZONE REMAINS NEAR OR AT THE SURFACE. WHAT IS ALSO DIFFERENT FROM YESTERDAY IS THAT THE GFS IS DOING WHAT THE NAM WAS DOING YESTERDAY WHICH IS KEEPING A MIXTURE IN PLACE FOR MUCH LONGER. IF SOUNDINGS ARE CORRECT THE FAR SOUTH AND WEST MAY NOT DO A COMPLETE CHANGE OVER TO SNOW UNTIL AFTER MIDNIGHT. AM CONCERNED THAT THE MODELS MAY BE UNDERDOING PRECIPITATION/SNOW AMOUNTS DUE TO THE STRONG LIFT FROM THE JET/UPPER DEFORMATION MOVING ACROSS. BY MIDNIGHT THE MAIN AREA OF SNOW WILL HAVE MOVED INTO THE SOUTHEAST HALF AND THAT IS WHERE WE WILL HAVE TO WATCH AMOUNTS CAREFULLY. FOR MAXES...MODEL GUIDANCE IS WARMER AND THAT LOOKS TO BE MAINLY DUE TO THE MODELS NOT COOLING OFF TEMPERATURES AS MUCH FOR THIS MORNING. MAXES MAY BE EARLY. USED A COMBINATION OF HRRR AND MAV TO ADJUST THE MAXES. KEPT MINS WARMER AND ABOVE THE COLDEST GUIDANCE DUE TO THE CLOUDS AND UPSLOPE WINDS. CONSEQUENTLY THE WIND CHILL READINGS ARE NOT AS LOW AS PREVIOUS FEW DAYS WITH MARGINAL WIND CHILL ADVISORY CRITERIA ALONG AND EAST OF THE COLORADO BORDER. SUNDAY/SUNDAY NIGHT...MODELS DIFFERING ON THE SPEED/POSITION A LITTLE BUT IN GENERAL THEY SHOW THE RIGHT REAR QUADRANT AFFECTING THE SOUTHEAST HALF OF THE AREA AT THE BEGINNING OF THE DAY. THIS IS TO THE EAST OF THE AREA BY 18Z. IT IS ALSO BY THIS TIME THAT DOWNGLIDE IS OCCURRING ON 290 SURFACE. PRECIPITATION BE HIGHEST IN THE SOUTHEAST HALF OF THE FORECAST AREA DUE TO THE JET AND SHORTWAVE TROUGH. SO KEPT HIGHER POPS THERE AND LOWERED THEM OVER THE REST OF THE AREA. SNOW WILL GRADUALLY DECREASE DURING THE DAY WITH FLURRIES EXPECTED DURING THE EVENING. BASED ON SATURATED LOW LEVELS DID TOSS IN SOME PATCHY FREEZING FOG DURING THE OVERNIGHT HOURS. CLOUDS...UPSLOPE WINDS AND COLD AIR ADVECTION WILL BE PLACE FOR THE ENTIRE DAY. NOT SURE WHY MODEL GUIDANCE IS WARMING UP MAXES SO MUCH. KEPT THE MAXES NEAR THE COLDER SIDE AND NEAR THE BETTER PERFORMING GUIDANCE. MINS WILL BE WARMER THAN THE PREVIOUS NIGHT WHICH AGAIN MEANS WIND CHILL READINGS NOT GETTING AS COLD. AGAIN REACHING MARGINAL ADVISORY VALUES. MONDAY/MONDAY NIGHT...WEAK RIGHT REAR QUADRANT OF THE JET DEVELOPS OVER THE AREA BY THE MIDDLE OF THE DAY AND AFFECTS THE AREA AT LEAST THROUGH THE EVENING. THERE WILL BE A DEEP DRY LAYER SO ONLY CLOUDS WILL RESULT. SO THIS PERIOD WILL JUST END UP BEING A TEMPERATURE FORECAST. DEPENDING ON HOW MUCH SNOW FALLS AND WHERE... THAT COULD CAUSE IN THE TEMPERATURE LAYOUT I HAVE IN THERE. MODELS ARE BRINGING IN WARMER AIR FURTHER EAST AND FOR THE MOST PART I BELIEVE THEY ARE TOO AGGRESSIVE. SINCE THE ECMWF HAS A BETTER DEPICTION OF THE SURFACE...DO LIKE ITS TEMPERATURES A LITTLE BETTER. HOWEVER...MODELS HAVE HAD A TENDENCY TO HOLD TO COLD TEMPERATURES TOO LONG IN THIS PATTERN WHICH BECOMES STRONG ZONAL. WARM AIR ADVECTION PATTERN DEVELOPS IN ERNEST DURING THE NIGHT AND MAY END UP HAVING WARMING TEMPERATURES DURING THE OVERNIGHT HOURS. .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 419 AM MST SAT MAR 1 2014 NEAR TO ABOVE NORMAL TEMPERATURES WILL START OUT THIS PERIOD AS THE COLD FRONT FROM THE WEEKEND CONTINUES TO MOVE EAST OUT OF THE AREA. THE NEXT CHANCE FOR PRECIPITATION WILL BE WEDNESDAY AS AN UPPER LEVEL SHORT WAVE TROUGH MOVES ACROSS THE AREA BRINGING A BRIEF SHOT FOR SOME RAIN/SNOW. TEMPERATURES CONTINUE TO WARM THURSDAY AS A SHORT WAVE RIDGE BUILDS OVER THE AREA. HIGHS WILL BE IN THE 60S AND LOWS WILL BE IN THE 30S. FRIDAY ANOTHER STRONGER UPPER LEVEL SHORT WAVE TROUGH MOVES OVER THE AREA...REMAINING OVER THE AREA UNTIL SATURDAY. LATE FRIDAY AFTERNOON AND FRIDAY EVENING A COLD FRONT WILL MOVE THROUGH THE AREA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 446 AM MST SAT MAR 1 2014 COMPLICATED/MESSY SET OF TAFS...ESPECIALLY AT KGLD. IFR CEILINGS CAN BE EXPECTED AT KGLD THROUGH 06Z TONIGHT. THIS MORNING PRECIPITATION COULD RANGE AND CHANGE BACK AND FORTH FROM SNOW...SLEET AND FREEZING DRIZZLE. THIS IS CURRENTLY HAPPENING. THIS AFTERNOON THE PHASE TRANSITION WILL BE FROM A SLEET/SNOW MIX TO ALL SNOW BY LATE THIS AFTERNOON/EARLY THIS EVENING. VISIBILITIES DURING THIS TIME SHOULD STAY IN THE 3 TO 5 MILE RANGE. AT 06Z...MVFR CONDITIONS ARE EXPECTED. EASTERLY WINDS SHOULD BECOME GUSTY BY LATE THIS MORNING AND CONTINUE THROUGH THE AFTERNOON. FOR KMCK...SOME FOG CAN BE EXPECTED THIS MORNING WITH THE PHASE BEING SNOW. CONDITIONS AT KMCK WILL START AS MVFR AND THEN DROP TO IFR BY 18Z. IFR CONDITIONS WILL REMAIN UNTIL 06Z WHEN CEILINGS COME UP TO MVFR. VISIBILITIES WILL ALSO REMAIN IN THE 3 TO 5 MILE RANGE. EASTERLY WINDS SHOULD BECOME GUSTY BY LATE THIS MORNING AND CONTINUE THROUGH THE AFTERNOON. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...WINTER WEATHER ADVISORY UNTIL 5 PM MST /6 PM CST/ SUNDAY FOR KSZ001>004-013>016-027>029-041-042. CO...WINTER WEATHER ADVISORY UNTIL 5 PM MST SUNDAY FOR COZ090>092. NE...WINTER WEATHER ADVISORY UNTIL 5 PM MST /6 PM CST/ SUNDAY FOR NEZ079>081. && $$ SHORT TERM...BULLER LONG TERM...JTL AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
419 AM MST SAT MAR 1 2014 .SHORT TERM...(TODAY THROUGH MONDAY NIGHT) ISSUED AT 419 AM MST SAT MAR 1 2014 MAIN FORECAST CONCERNS...AMONG VERY MANY...WILL BE PHASE OF PRECIPITATION AND AMOUNT OF ICE AND SNOW ACCUMULATION INTO TOMORROW SATELLITE CONTINUING TO SHOW AN AMPLIFIED/COMPLEX AND EVEN RETROGRESSIVE PATTERN FROM THE PACIFIC INTO CANADA. HIGH AMPLITUDE RIDGE RESIDES ALONG THE WEST COAST OF NORTH AMERICA WITH BROAD AND COLD UPPER TROUGH OVER CANADA. WEAKENING/FILLING SYSTEM IS MOVING TOWARD THE CALIFORNIA COAST WITH A LARGE AMOUNT OF MID AND UPPER LEVEL MOISTURE STREAMING OUT AHEAD OF IT. A SIGNIFICANT LOBE ROTATING AROUND THE CANADIAN TROUGH IS PUSHING SOUTH. AT JET LEVEL...MODELS INITIALIZED POORLY WITH JET SEGMENT IN ADVANCE OF SYSTEM OFF THE CALIFORNIA COAST. THE UKMET AND NAM WERE DOING THE BEST BUT WERE STILL OFF. AT MID LEVELS...THE GFS...ECMWF ...CANADIAN AND SREF WERE DOING ABOUT THE SAME AND THE BEST OF THE AVAILABLE OUTPUT. THE ECMWF WAS DOING A LITTLE BETTER THAN THE SREF ON THE SURFACE WIND AND PRESSURE FIELD. THE UKMET...GFS...NAM AND CANADIAN WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD. EVEN THOUGH THEY ARE NOT PRODUCING A LOT OF QPF...THEY ARE TENDING TO OVERDO IT WITH THE GFS...NAM...AND SREF THE WORST. THIS WILL CONTINUE TO BE A VERY LOW CONFIDENCE FORECAST DUE TO POOR INITIAL ON MID AND UPPER LEVEL FEATURES...MODEL DIFFERENCES IN THERMAL AND MOISTURE PROFILES...AND MODELS CHANGING FROM THEIR SOLUTIONS...SOMETIMES DRAMATICALLY...FROM 24 HOURS AGO. SAYING ALL THAT...THE WINTER WEATHER ADVISORY DOES STILL LOOK ON TRACK DUE TO THE VARIABLE PHASES AND SNOW AMOUNTS. TODAY/TONIGHT...JET SETUP BY THE END OF THE DAY IS DIFFERENT THAN WHAT WAS DEPICTED YESTERDAY. BY LATE IN THE DAY THE MAIN JET SEGMENT IS STILL TO THE WEST OF MY AREA WITH THE RIGHT FRONT QUADRANT OVER THE AREA. SO AT FIRST GLANCE THERE DOES NOT APPEAR TO BE A LOT TO DRIVE PRECIPITATION DEVELOPMENT DUE TO ANY STRONG FEATURES. HOWEVER...MODELS DO CONTINUE TO PRODUCE LIGHT AMOUNTS OF QPF. THE LIFT IS BEING GENERATED BY LOW LEVEL UPSLOPE AND ISENTROPIC LIFT ABOVE THIS DOME OF COLD AIR. PRECIPITATION HAS BEEN SLOWER TO START THAN WHAT WAS PREVIOUSLY EXPECTED SURFACE OBSERVATIONS ARE STARTING TO SHOW IT. SO BELIEVE WILL LIGHT PRECIPITATION AROUND FOR MOST OF THE DAY. SO QUESTION BECOMES PHASE. 00Z SOUNDINGS SHOW EITHER A DRY AIR MASS OR ONLY A SATURATED SHALLOW AIR MASS AND THAT WAS EVIDENT IN SOME FOG DEVELOPMENT. GFS HAS CHANGED ITS TUNE FROM YESTERDAY. IT IS NOT AS AGGRESSIVE IN SATURATING THE COLUMN TO A DEEPER DEPTH. THE NAM ALSO CHANGED ITS TUNE AND SATURATED TO GREATER DEPTH...AT LEAST IN THE BEGINNING...IN A SIMILAR AS THE GFS WHICH IS SLIGHTLY DRIER ALOFT THAN THE NAM. WARM LAYER APPEARS IN ALL AREAS OR ALMOST ALL AREAS AT THE BEGINNING WITH THE GFS SHOWING WARMER TEMPERATURES ALOFT. NORTHERN AREAS SHOULD SEE ALL SNOW ONLY BECAUSE THE DENDRITIC ZONE IS AT THE SURFACE. FOR A FEW COUNTIES SOUTH AND WEST OF THAT A MIXTURE OF FREEZING DRIZZLE...SNOW AND SLEET IS INDICATED WITH THE FAR SOUTH AND WEST INDICATING SLEET AND FREEZING DRIZZLE. THIS AREA WORKS ITS WAY SOUTH GRADUALLY THROUGH THE DAY. ALL IN ALL THE PREVIOUS FORECAST HAD THE POP AND PHASE LAYOUT IN GOOD SHAPE AND ONLY MADE MINOR ADJUSTMENTS. WITH NOT VERY STRONG LIFT...DID REDUCE THE ALREADY LIGHT SNOW AMOUNTS A LITTLE. RIGHT REAR QUADRANT OF THE JET MOVES ACROSS THE AREA DURING THE NIGHT. AT THE SAME A SHORTWAVE TROUGH MOVES ACROSS THE AREA WITH ISENTROPIC LIFT STILL IN PLACE. GFS CONTINUES TO NOT HAVE A DEEP OF A SATURATED LAYER AS YESTERDAY. HOWEVER...THE DENDRITIC ZONE REMAINS NEAR OR AT THE SURFACE. WHAT IS ALSO DIFFERENT FROM YESTERDAY IS THAT THE GFS IS DOING WHAT THE NAM WAS DOING YESTERDAY WHICH IS KEEPING A MIXTURE IN PLACE FOR MUCH LONGER. IF SOUNDINGS ARE CORRECT THE FAR SOUTH AND WEST MAY NOT DO A COMPLETE CHANGE OVER TO SNOW UNTIL AFTER MIDNIGHT. BY THE EARLY MORNING HOURS SHOULD CHANGE OVER TO SNOW. AM CONCERNED THAT THE MODELS MAY BE UNDERDOING PRECIPITATION/SNOW AMOUNTS DUE TO THE STRONG LIFT FROM THE JET/UPPER DEFORMATION MOVING ACROSS. BY MIDNIGHT THE MAIN AREA OF SNOW WILL HAVE MOVED INTO THE SOUTHEAST HALF AND THAT IS WHERE WE WILL HAVE TO WATCH AMOUNTS CAREFULLY. FOR MAXES...MODEL GUIDANCE IS WARMER AND THAT LOOKS TO BE MAINLY DUE TO THE MODELS NOT COOLING OFF TEMPERATURES AS MUCH FOR THIS MORNING. MAXES MAY BE EARLY. USED A COMBINATION OF HRRR AND MAV TO ADJUST THE MAXES. KEPT MINS WARMER AND ABOVE THE COLDEST GUIDANCE DUE TO THE CLOUDS AND UPSLOPE WINDS. CONSEQUENTLY THE WIND CHILL READINGS ARE NOT AS LOW AS PREVIOUS FEW DAYS WITH MARGINAL WIND CHILL ADVISORY CRITERIA ALONG AND EAST OF THE COLORADO BORDER. SUNDAY/SUNDAY NIGHT...MODELS DIFFERING ON THE SPEED/POSITION A LITTLE BUT IN GENERAL THEY SHOW THE RIGHT REAR QUADRANT AFFECTING THE SOUTHEAST HALF OF THE AREA AT THE BEGINNING OF THE DAY. THIS IS TO THE EAST OF THE AREA BY 18Z. IT IS ALSO BY THIS TIME THAT DOWNGLIDE IS OCCURRING ON 290 SURFACE. PRECIPITATION BE HIGHEST IN THE SOUTHEAST HALF OF THE FORECAST AREA DUE TO THE JET AND SHORTWAVE TROUGH. SO KEPT HIGHER POPS THERE AND LOWERED THEM OVER THE REST OF THE AREA. SNOW WILL GRADUALLY DECREASE DURING THE DAY WITH FLURRIES EXPECTED DURING THE EVENING. BASED ON SATURATED LOW LEVELS DID TOSS IN SOME PATCHY FREEZING FOG DURING THE OVERNIGHT HOURS. CLOUDS...UPSLOPE WINDS AND COLD AIR ADVECTION WILL BE PLACE FOR THE ENTIRE DAY. NOT SURE WHY MODEL GUIDANCE IS WARMING UP MAXES SO MUCH. KEPT THE MAXES NEAR THE COLDER SIDE AND NEAR THE BETTER PERFORMING GUIDANCE. MINS WILL BE WARMER THAN THE PREVIOUS NIGHT WHICH AGAIN MEANS WIND CHILL READINGS NOT GETTING AS COLD. AGAIN REACHING MARGINAL ADVISORY VALUES. MONDAY/MONDAY NIGHT...WEAK RIGHT REAR QUADRANT OF THE JET DEVELOPS OVER THE AREA BY THE MIDDLE OF THE DAY AND AFFECTS THE AREA AT LEAST THROUGH THE EVENING. THERE WILL BE A DEEP DRY LAYER SO ONLY CLOUDS WILL RESULT. SO THIS PERIOD WILL JUST END UP BEING A TEMPERATURE FORECAST. DEPENDING ON HOW MUCH SNOW FALLS AND WHERE... THAT COULD CAUSE IN THE TEMPERATURE LAYOUT I HAVE IN THERE. MODELS ARE BRINGING IN WARMER AIR FURTHER EAST AND FOR THE MOST PART I BELIEVE THEY ARE TOO AGGRESSIVE. SINCE THE ECMWF HAS A BETTER DEPICTION OF THE SURFACE...DO LIKE ITS TEMPERATURES A LITTLE BETTER. HOWEVER...MODELS HAVE HAD A TENDENCY TO HOLD TO COLD TEMPERATURES TOO LONG IN THIS PATTERN WHICH BECOMES STRONG ZONAL. WARM AIR ADVECTION PATTERN DEVELOPS IN ERNEST DURING THE NIGHT AND MAY END UP HAVING WARMING TEMPERATURES DURING THE OVERNIGHT HOURS. .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 419 AM MST SAT MAR 1 2014 NEAR TO ABOVE NORMAL TEMPERATURES WILL START OUT THIS PERIOD AS THE COLD FRONT FROM THE WEEKEND CONTINUES TO MOVE EAST OUT OF THE AREA. THE NEXT CHANCE FOR PRECIPITATION WILL BE WEDNESDAY AS AN UPPER LEVEL SHORT WAVE TROUGH MOVES ACROSS THE AREA BRINGING A BRIEF SHOT FOR SOME RAIN/SNOW. TEMPERATURES CONTINUE TO WARM THURSDAY AS A SHORT WAVE RIDGE BUILDS OVER THE AREA. HIGHS WILL BE IN THE 60S AND LOWS WILL BE IN THE 30S. FRIDAY ANOTHER STRONGER UPPER LEVEL SHORT WAVE TROUGH MOVES OVER THE AREA...REMAINING OVER THE AREA UNTIL SATURDAY. LATE FRIDAY AFTERNOON AND FRIDAY EVENING A COLD FRONT WILL MOVE THROUGH THE AREA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1025 PM MST FRI FEB 28 2014 VERY DIFFICULT FORECAST FOR BOTH KGLD AND KMCK. WHAT WE CAN SAY WITH SOME CONFIDENCE IS CIGS WILL BE MVFR-IFR THROUGH THE PERIOD. KGLD...EAST WINDS 10-15KTS TO VEER SLIGHTLY TO THE EAST/SOUTHEAST BY 12Z THEN SLOWLY BACK TO THE NORTHEAST AND INCREASE 15G25KTS OR SO THROUGH THE DAY. GUSTS SHOULD DISSIPATE SHORTLY AFTER 00Z OR SO WITH PRIMARY WIND FROM THE NORTHEAST AROUND 10KTS. PRECIP TYPE/INTENSITY WILL BE CHALLENGING. NOT EXPECTING PRECIP TIL THE 09Z-12Z TIMEFRAME WHEN LOW LEVEL CONVERGENCE INCREASES A BIT AND REMAINS SO THROUGH MUCH OF THE DAY. SHOULD SEE A MIX OF -FZDZSN INITIALLY WITH POSSIBLY A TRANSITION TO -PLSN AFTER 15Z OR SO WITH LIGHT SNOW EXPECTED BY LATE MORNING THROUGH THE REST OF THE TAF PERIOD. SOME FOG/MIST ALSO EXPECTED. CONFIDENCE IS LOW. KMCK...NORTHEAST WINDS AROUND 15KTS EXPECTED TO VEER SLIGHTLY TO THE EAST BY 09Z AND REMAIN SO WHILE ALSO BECOMING GUSTY FROM 15Z THROUGH THE DAY THEN DECREASE TOWARD 10KTS AFTER SUNSET. PRECIP TYPE SHOULD BE ALL SNOW. CONFIDENCE IN TIMING IS LOW. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...WINTER WEATHER ADVISORY FROM 8 PM MST /9 PM CST/ THIS EVENING TO 5 PM MST /6 PM CST/ SUNDAY FOR KSZ001>004-013>016-027>029- 041-042. CO...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 5 PM MST SUNDAY FOR COZ090>092. NE...WINTER WEATHER ADVISORY FROM 8 PM MST /9 PM CST/ THIS EVENING TO 5 PM MST /6 PM CST/ SUNDAY FOR NEZ079>081. && $$ SHORT TERM...BULLER LONG TERM...JTL AVIATION...DDT
AREA FORECAST DISCUSSION
NWS TOPEKA KS
430 AM CST Sat Mar 1 2014 .SHORT TERM...(Today) Issued at 430 AM CST SAT MAR 1 2014 High pressure continues to nose south into the Plains early this morning with local values ranging from the teens in the north to near freezing in the south. Low level winds via upstream profiles show north to northeast winds over the lower few thousand feet, though sensors in Kansas indicate veering winds over the cold dome. First hints and higher near-surface saturation occurring here with EMP visibility at 7 SM and somewhat enhanced reflectivities from KTWX. 0Z upper air obs from KAMA, KDDC, and KLBF showing drier mid levels behinds yesterday`s weak wave. Latest guidance quite similar and not different from earlier forecasts. Mid level isentropic lift increases through the day, but still much dry air to overcome to get precipitation generated aloft to reach the ground. Deeper saturation takes place from northwest to southeast and have modest precipitation chances following this afternoon. Much of the day will see some concern for very light precip formed via 900-800 mb frontogenesis. Lower clouds already in place so not much lift should be needed to get something to fall, especially later in the day. Lift seems to be high enough into the frontal zone for this to occur temps warmer than ice crystal formation values, but fall into colder, ice-generating temps. Along with inherent uncertainty in the models handling of the near-surface layers, have mentioned both freezing drizzle and flurries, but if the former can dominate, become persistent and heavy, initial travel problems could occur before main precip starts and this will need to be watched today. Continued near-surface cold air advection should bring slowly falling temps. (Tonight through Monday)... Complex weather scenario tonight through Sunday. The upper low was still over the eastern Pacific off the California coast this morning will move onshore today then out into the Rockies tonight before moving out into the Southern and Central Plains on Sunday. Main concern with this system is the amount of warm air above the cold dome. 00Z NAM was the most aggressive with the warm nose...while the 06Z run backed off a little with the regards to the northern extent of the warm air. Good isentropic lift will be ongoing this evening and strengthening overnight. Forecast time sections show prolonged frontogenetic forcing along with periods of CI or CSI trending toward banded precipitation and locally higher amounts. As mentioned above with regards to the warm nose, forecast soundings suggest that much of east central and northeast Kansas will see a prolonged period of sleet this evening and into the early morning hours on Sunday before becoming all snow. The sleet could accumulate up to an inch. There still is some uncertainty with snowfall amounts as the placement of the heavy band could change. Have decided to issue a Winter Storm Warning for the snow and sleet combination and amounts may need to be further refined with time. Current thinking is that anywhere from 3 to 7 inches is possible. The NAM is the faster of the model solutions with bringing in the dry air and ending precipitation. Trended toward the GFS and ECMWF with timing. However the new 06Z GFS is even a little slower than the 00Z run. The upper trough is forecast to move off to the east Sunday night with precipitation coming to an end during the evening hours. In addition to the snow and sleet very cold temperatures and winds of 15 to 20 mph will produce wind chills of 15 to 21 below tonight and from 18 to 23 below zero Sunday night. High pressure will move into the eastern Kansas on Monday. Lows tonight will fall into the single digits with areas along the Nebraska border ranging from zero to 2 below. Highs on Sunday will rise little with temperatures remaining in the 4 to 7 degree range. .LONG TERM...(Monday night through Friday) Issued at 430 AM CST SAT MAR 1 2014 Monday night through Friday... A few longer-wavelength waves remain on track to pass mainly west to east through the region. ECMWF stronger with the first on Monday night into early Tuesday but hard to see anything but trace amounts falling in even the stronger scenario. Next wave around Wednesday deepens as it passes for a somewhat better precip opportunity, with the final around the end of the forecast, again looking to deep as it comes east, but much uncertainty in just how this wave pans out. Temperatures still should generally moderate with time however. && .AVIATION...(For the 06Z TAFs through 06Z Saturday Night) Issued at 1102 PM CST FRI FEB 28 2014 Models are in reasonable agreement that MVFR CIGS will persist through the period. The RAP and NAM isentropic surfaces continue to show relatively deep upglide developing by mid morning, and think there is a good chance for patchy freezing drizzle and flurries in the late morning and through the afternoon. Confidence in the start of the heavier banded sleet and snow with possible IFR CIGS and VSBY is a little more marginal, and may begin closer to 06Z Sunday. Therefore will not include any IFR conditions at this time and let later shifts refine the timing. && .TOP WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING from 6 PM this evening to Midnight CST Sunday Night FOR KSZ022>024-026-035>040. WINTER WEATHER ADVISORY from 6 PM this evening to Midnight CST Sunday Night FOR KSZ008>012-020-021-034. WINTER STORM WARNING from 6 PM this evening to 6 AM CST Monday FOR KSZ054>056-058-059. && $$ SHORT TERM...65/53 LONG TERM...65 AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1102 PM CST Fri Feb 28 2014 ...AVIATION UPDATE... .UPDATE... Issued at 950 PM CST FRI FEB 28 2014 Have updated the forecast to hold off on the patchy freezing drizzle until after 12Z Saturday. The RAP/NAM/GFS isentropic progs show the upglide developing between 12 and 15Z. Think this is when any patchy freezing drizzle is most likely to occur, and it still looks like some flurries could fly through the day as the lower portion of the forecast soundings cool down enough for dendrites to form. The 00Z NAM has not cleared things up much. It is now more aggressive in advecting dry air in from the north and ends the precip by Sunday morning. Do not have much confidence in making adjustments based solely off the NAM so will maintain the watch for now. In general it looks like we could see some isentropic upglide through the day Saturday, then a band of frontogenesis moving across central and eastern KS overnight. Forecast soundings from the 00Z NAM continue to suggest sleet may be the more predominate precip type with its warm nose remaining over much of the area until midnight. With no cyclogenesis or strong synoptic scale forcing progged by any of the models (upper closed low progged to weaken quite a bit as it moves across the Rockies and become an open wave moving across OK) am wondering if a shorter duration event is becoming more likely. Will wait to digest the GFS and other models before making substantial changes to the forecast. && .SHORT TERM...(This Evening through Saturday) Issued at 404 PM CST FRI FEB 28 2014 Current sfc analysis places the cold front or trough across central KS and into SE NE. The arctic front associated with the cold air is plowing southward through central NE at the moment, and should reach the northwest forecast area in about an hour or two, and exit the southeast forecast area by around midnight. Ahead of the front low level moisture has been slow to spread northward, but has finally made it into most of northern KS in the form of a stratus deck. With the moisture in place isolated to scattered rain showers are possible along and behind the front mainly north of interstate 70 for the rest of this evening as it progresses eastward along the NE KS border. Any precip that falls should remain light. Winds shift behind the front the to NNE and increase to around 15 mph with gusts up to 20 mph. Some of the latest guidance is suggesting the low level lift and saturation remains over eastern KS through the overnight hours. With temperatures rapidly falling behind the front there could be a period of light freezing drizzle. As the deep cold air continues to filter southward temperatures within the layer of lift may be cold enough for ice growth therefore flurries could mix in as well. The NAM keeps the lift through tomorrow afternoon, although there could be a lull early tomorrow morning before picking up again ahead of the approaching system. Do not expect much impact from the freezing drizzle since the warm temperatures today and flurries could mix in as well. Also not confident how long the low level lift persists behind the front. Temperatures will bottom out overnight and should reach the low 10s in north central KS to the mid 20s in far east central KS by sunrise tomorrow. Temperatures will basically remain steady through the day tomorrow with the highs only a few degrees warmer than the morning lows as of now. As the lift and saturation increases in the mid levels tomorrow afternoon snow could develop especially areas north of interstate 70. Models do agree that the warm nose could still be present tomorrow afternoon as far north as the NE KS border so could not rule out periods of sleet as well. .LONG TERM...(Saturday Night through Friday) Issued at 404 PM CST FRI FEB 28 2014 The bulk of the attention today was placed on the period from Saturday evening through Monday morning, when a potentially significant winter storm combined with dangerously cold wind chills will impact the area. From a forecast perspective, uncertainty is higher than normal and the potential spread of forecast solutions is quite large. So, while the entire area will experience hazardous winter weather, the magnitude of the winter storm remains very much in question. In this rather complex weather scenario, the first player will be an upper trough and jet max that moves well to our north and into the Great Lakes region. This system will send increasingly cold air into Kansas, air which will also be a bit drier in nature. The associated frontogenesis and favorable jet dynamics will also provide enhanced vertical motion across the area and associated precipitation. At the same time...a well developed storm system will move out of the southern Rockies. Ahead of this trough, a broad area of warm moist advection will overtake the Southern Plains and nose into the Central Plains...overriding the cold air incoming from the north. This will create a very dynamic situation by Saturday evening through Sunday morning during which a battle between dry cold advection from the north and moist warm advection from the south will result in bands of probably intense vertical motion. In more detail, these bands will be comprised mainly of intense frontogenesis in the mid levels, isentropic ascent within and above the nose of warm advection aloft, favorable jet dynamics, and the coincidence of this lift with weakly stable to convectively unstable thermal profiles. The expected result is a WSW to ENE oriented band of heavy precipitation gradually moving south across the area from Saturday evening into Sunday. As the southwest trough approaches, the progression of the heavy precipitation band will slow and nearly stop...with some model guidance suggesting additional precipitation developing north of the heaviest band and spreading back across the area. Some of the latest mid day guidance however is more aggressive with the intrusion of the northerly dry air and maintains a track of the upper trough a bit farther south...which would limit precip in northern parts of the forecast area on Sunday. There are currently two primary questions with this forecast. The first is the magnitude of the dry air incoming from the north. If this airmass marches well into the forecast area on Sunday...which would also be tied to the storm track of the incoming upper trough...then precip amounts on Sunday would be substantially lower especially north of I-70. If this precip falls, it would be entirely snow so any reduction in precip on Sunday would be a stark reduction in snow totals on top of any sleet/snow combo that falls with the heaviest band. The other primary forecast question revolves around whether we get more sleet or snow as the heaviest band drifts overhead. Sleet is definitely favored early in the event near and south of I-70, and it could pile up quickly before turning over to snow. This would cause snow amounts to be much lower however. The current forecast reflects this in lower snow amounts along the I-35 corridor despite higher expected liquid content. A quicker change over to snow would obviously result in less sleet and a lot more snow. As it stands, expect some locations especially near and south of I-35 to be in the 0.5 to 1 inch of sleet range. Snow amounts near the Nebraska border should be lightest...probably in the 1-5 inch range with more uncertainty farther south. Would not be surprised to have several observations of 6 to 8 inches in addition to some sleet. With all of this in mind, have maintained the winter storm watch for most of the area, but did issue a winter weather advisory for the far northern counties as the probability of a non-warning winter weather event is likely in this area. Wind chills will be very cold from Saturday night through Monday morning, and will not rise above -10 during the day on Sunday before approaching -25 on Monday morning. Beyond Monday, a gradual warming trend is expected with no high impact weather expected through the remainder of the forecast. && .AVIATION...(For the 06Z TAFs through 06Z Saturday Night) Issued at 1102 PM CST FRI FEB 28 2014 Models are in reasonable agreement that MVFR CIGS will persist through the period. The RAP and NAM isentropic surfaces continue to show relatively deep upglide developing by mid morning, and think there is a good chance for patchy freezing drizzle and flurries in the late morning and through the afternoon. Confidence in the start of the heavier banded sleet and snow with possible IFR CIGS and VSBY is a little more marginal, and may begin closer to 06Z Sunday. Therefore will not include any IFR conditions at this time and let later shifts refine the timing. && .TOP WATCHES/WARNINGS/ADVISORIES... WINTER STORM WATCH from Saturday evening through late Sunday night FOR KSZ021>024-026-034>040-054>056-058-059. WINTER WEATHER ADVISORY from 6 PM Saturday to 6 AM CST Monday FOR KSZ008>012-020. && $$ UPDATE...Wolters SHORT TERM...Sanders LONG TERM...Barjenbruch AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GRAY ME
244 PM EST SAT MAR 1 2014 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT THEN PUSH SOUTHEAST OF THE REGION SUNDAY. LOW PRESSURE WILL TRACK EAST ALONG THIS FRONT WELL SOUTH OF THE REGION SUNDAY NIGHT AND MONDAY. COLD HIGH PRESSURE WILL BUILD IN BEHIND THE LOW MONDAY INTO TUESDAY. ANOTHER COLD FRONT WILL CROSS THE AREA TUESDAY NIGHT FOLLOWED BY COLD HIGH PRESSURE. THE HIGH WILL MOVE OFF THE COAST THURSDAY NIGHT AND FRIDAY ALLOWING MILDER AIR TO FLOW INTO THE REGION WITH AN INCREASING CHANCE OF PRECIPITATION. && .NEAR TERM /THROUGH TONIGHT/... CLOUDS WILL CONTINUE TO THICKEN DURING THE OVERNIGHT HOURS AHEAD OF ATHE PPROACHING FRONT. LIGHT SNOW SHOWERS WILL BE MOST FREQUENT TONIGHT IN THE NORTH AND MOUNTAINS WHERE ELEVATED TERRAIN WILL ALLOW FOR LIGHT ACCUMULATIONS OF SNOW. MESOSCALE MODELS CONSISTENT WITH THIS IDEA...HOWEVER THE LASTEST HRRR RUN APPEARS TO BE OVERDONE WITH PRECIP FOR THE COASTAL REGIONS OVERNIGHT. MIN TEMPS WILL BE MUCH WARMER OVERNIGHT THAN LAST NIGHT WITH CLOUD COVER AND RADIATIONAL COOLING. SOME OF OUR COLDEST SPOTS LAST NIGHT REACHED 20 BELOW ZERO. && .SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/... THE FRONT WILL SAG WELL SOUTH OF OUR FORECAST AREA AFTER IS PASSES THROUGH NEW ENGLAND SUNDAY MORNING. 12Z MODEL SUITE NOW EVEN FURTHER SOUTH WITH THIS SYSTEM WITH THE TRACK OF THE SURFACE LOW NEAR THE CAROLINAS. TEMPERATURES WILL BE NEAR 32 DEGREES IN PORTLAND TOMORROW. IF WE DO BREAK THE FREEZING POINT...IT WILL BE AFTER QUITE A PROLONGED PERIOD OF BELOW FREEZING WEATHER. THEREAFTER...WE ARE BACK INTO THE DEEP FREEZE WITH TEMPERATURES NEAR OR BELOW ZERO...EVEN ALONG THE COAST AS WE MOVE INTO THE LONG RANGE PORTION OF THE FORECAST. && .LONG TERM /MONDAY THROUGH SATURDAY/... QUIET BUT COLD WEATHER EXPECTED FOR MUCH OF THE LONG TERM PERIOD. COLD HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE DEPARTING LOW WELL SOUTH OF THE REGION. MODELS CONTINUE TO TREND FARTHER SOUTH WITH THIS SYSTEM WITH NO SNOW PREDICTED FOR OUR AREA MONDAY. A SECOND FRONT CROSSES THE AREA TUESDAY. ONLY MINIMAL MOISTURE WITH THIS FRONT SO EXPECT ONLY A SLIGHT CHANCE OF SNOW SHOWERS...MOSTLY IN THE MOUNTAINS. ANOTHER COLD HIGH BUILDS IN FOR WEDNESDAY AND THURSDAY. THE RETURN FLOW ON THE BACK SIDE OF THE HIGH WILL BRING WARMER TEMPS IN FOR FRIDAY AND POSSIBLY UNSETTLED WEATHER FOR NEXT WEEKEND. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... SHORT TERM... MAINLY VFR CONDITIONS...HOWEVER AREAS OF MVFR CONDITIONS IN THE NORTH AND MOUNTAINS IN SNOW SHOWERS OVERNIGHT. LONG TERM... NO SIGNIFICANT WEATHER EXPECTED. WIDELY SCATTERED SNOW SHOWERS TUESDAY NIGHT. && .MARINE... SHORT TERM... SOUTHWEST GRADIENT WILL BE ON THE INCREASE OVERNIGHT...HENCE SCAS REMAIN IN EFFECT OVERNIGHT. LONG TERM... WINDS AND SEAS AT OR BELOW SCA THROUGH THE FRIDAY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ150>152-154. && $$ SYNOPSIS... NEAR TERM...JC SHORT TERM...JC LONG TERM...JENSENIUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
401 PM EST SAT MAR 1 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 349 PM EST SAT MAR 1 2014 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A PERSISTENT TROF OVER CANADA WITH CORE OF COLDEST AIR/CLOSED UPR LO OVER HUDSON BAY. 12Z H85 TEMPS UNDER THE LOWEST HGTS ARE AOB -30C...INDLUDING -30C AT INL AND -33C AT YPL. WITH A LLVL NW FLOW E OF ARCTIC HI PRES OVER THE CNDN PRAIRIES BLDG INTO THE NRN PLAINS...THIS COLD AIR IS ADVECTING INTO UPR MI. ALTHOUGH LATEST VSBL STLT IMAGERY SHOWS LK SUP IS MAINLY ICE COVERED...THERE ARE STILL SOME CLD/SHSN BANDS STREAMING INTO THE AREA AS THE UPSTREAM 12Z INL/YPL RAOBS SHOWED A RELATIVELY MOIST LLVL AIRMASS. BUT ANY PCPN HAS BEEN ON THE LGT SIDE...WITH EXTENSIVE ICE AND LLVL ACYC FLOW TENDING TO LIMIT THE INTENSITY OF THE SHSN. ONSET OF DAYTIME HEATING WITH INCRSG EARLY MARCH SUN ANGLE HAS ALSO RESULTED IN MORE INSTABILITY CU/SC OVER LAND AS WELL. SOME THICKER MID/HI CLDS ARE IMPACTING WI AND SRN UPR MI ON THE NRN FLANK OF DISTURBANCE/DEEPER MSTR TO THE S. SN UNDER SOME UPR DVGC IN RRQ OF 140KT H3 JET MAX STREAKING ACRS NRN MN/LK SUP IS AS FAR N AS SRN MN. MAIN FCST CONCERNS IN THE SHORT TERM ARE CLD TRENDS/CONTINUED BLO NORMAL TEMPS. TNGT...AS CNDN HI PRES CONTINUES TO BLD INTO THE NRN PLAINS...AN ACYC NW FLOW WL DOMINATE THE UPR LKS. ALTHOUGH SOME UPR DVGC ASSOCIATED WITH JET STREAK MOVING THRU THE UPR LKS WL PASS ACRS THE SCENTRAL THIS EVNG...GENERAL DRY ADVECTION IN THE H85-7 LYR SHOULD SUPPRESS NRN EDGE OF PCPN SHIELD TO THE S OF MENOMINEE. ALTHOUGH SOME LK CLDS/A FEW SN SHOWERS OFF LK SUP MAY LINGER UNDER THE COLD FLOW IN THE EVNG...LOSS OF DAYTIME HEATING AS WELL AS ACYC FLOW/ LOWERING SUBSIDENCE INVRN TOWARD 2K FT SHOWN ON FCST SDNGS SHOULD RESULT IN ALMOST COMPLETE SUPPRESSION OF CLDS/SN SHOWERS OVERNGT. WITH SKIES TURNING MOCLR AND PWAT UNDER 0.10 INCH...EXPECT SFC TEMPS TO TUMBLE AOB -20F AT MANY OF THE INTERIOR COLD SPOTS. GIVEN THE EXTENSIVE ICE COVER OF THE LK THAT WL TEND TO RESULT IN LOWER TEMPS OVER THE CWA...TRENDED TOWARD THE LO END OF GUIDANCE FOR MIN TEMPS FCST. LOWERING INVRN BASE/INCRSG STABILITY SHOULD KEEP SFC WINDS UNDER THE 10 MPH THRESHOLD FOR WIND CHILL HEADLINES...BUT ISSUED AN SPS TO HIGHLIGHT THE RESULTING VERY LO APRNT/WIND CHILL TEMPS THAT WL FALL AS LO AS -35F AT SOME PLACES. SUN...THERE WL BE A SHRTWV TRACKING SEWD TO THE NE OF UPR MI AND THRU ONTARIO...BUT BULK OF ASSOCIATED UPR FORCING WL REMAIN TO THE NE OF UPR MI. ALTHOUGH DAYTIME HEATING AND PASSAGE OF ATTENDANT WEAK SFC LO PRES TROF MAY RESULT IN SOME CLDS AND EVEN A FEW LGT SN SHOWERS MAINLY OVER THE NE HALF OF THE CWA TOWARD THE ACCOMPANYING DYANMIC FORCING...LO INVRN BASES SHOULD LIMIT THIS POTENTIAL. H85 TEMPS ARE FCST TO RANGE FM NEAR -20C OVER THE SCENTRAL TO AS LO AS -24C OR -25C OVER THE N. WITH THE EXTENSIVE ICE COVER...TEMPS WL REMAIN WELL BLO NORMAL DESPITE A GOOD DEAL OF SUNSHINE. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 359 PM EST SAT MAR 1 2014 MODELS SUGGEST THAT THE OVERALL PATTERN WILL UNDERGO A GRADUAL TRANSITION AWAY FROM THE VERY COLD AIR AS THE HIGH LATITUDE RIDGING INTO ERN AK SHIFTS WESTWARD INTO ERN SIBERIA. THE RESULTING DOWNSTREAM PATTERN WILL ALLOW THE SEVERE ARCTIC AIRMASS TO SHIFT OFF TO THE NE AND MORE MODERATE PACIFIC AIR INTO THE CNTRL CONUS. HOWEVER...A TREND BACK TOWARD RIDING ALONG THE WEST COAST WITH NW FLOW INTO THE NRN LAKES WILL KEEP ENOUGH COLD AIR IN THE REGION FOR BELOW NORMAL TEMPS AGAIN BY NEXT WEEKEND. SUN NIGHT...FAVORABLE RADIATIONAL COOLING CONDITIONS WITH THE SFC RIDGE AXIS INTO UPPER MICHIGAN WILL ALLOW TEMPS TO AGAIN DROP TO THE LOWER END OF GUIDANCE...INTO THE -20F TO -30F RANGE INLAND WITH TEENS BELOW READINGS CLOSER TO THE LAKES. THERE MAY BE ENOUGH OPEN WATER PATCHES OVER THE S CNTRL LAKE FOR SOME ISOLD -SHSN INTO THE NE CWA. HOWEVER...LITTLE OR NO ACCUMULATION IS EXPECTED. MON INTO TUE...PARTLY TO MOSTLY SUNNY SKIES MON SHOULD ALLOW TEMPS TO REBOUND INTO THE 10F TO 15F RANGE. WNW TO W WINDS SHOULD KEEP ANY LIGHT LES NEAR THE SHORE IN THE NE CWA. A CLIPPER SHORTWAVE TROUGH COULD BRING AN AREA OF MORE WIDESPREAD LIGHT SNOW TO THE AREA MON NIGHT INTO EARLY TUE. SINCE THE MODELS STILL SHOWED DIFFERENCES WITH THE GFS FARTHER SOUTH WITH THIS FEATURE COMPARED TO THE ECMWF/GEM...ONLY SLIGHT CHANCE POPS WERE MENTIONED. EVEN THE MORE NRN TRACK WOULD ONLY SUPPORT LIGHT ACCUMULATIONS OF AN INCH OR LESS. WED...MODELS WERE IN AGREEMENT THAT HIGH PRES WILL DOMINATE THE AREA WITH DRY WEATHER AND MORE MODERATE BUT STILL BELOW NORMAL TEMPERATURES INTO THE TEENS. THU-SAT...ANOTHER STRONGER SHORTWAVE IS EXPECTED TO MOVE THROUGH THE NRN LAKES BY THU NIGHT INTO FRI. THERE IS A BETTER CHANCE FOR SOME ACCUMULATING SNOW WITH THIS SYSTEM WITH BETTER MOISTURE AVAILABILITY. CHANCE POPS WERE MENTIONED GIVE TIMING/STRENGTH DIFFERENCES. THE WARMEST CONDITONS OF THE WEEK ARE POSSIBLE BY THU WITH TEMPS NEAR 30F. HIGH PRES IN THE WAKE OF THE SHRTWVM SHOULD BRING IN SLIGHTLY COOLER AIR WITH READINGS BACK INTO THE LOWER 20S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1225 PM EST SAT MAR 1 2014 EXPECT HI END MVFR TO VFR CONDITIONS THIS AFTN TO GIVE WAY TO JUST VFR WX THIS EVNG THRU SUN AS STRONG SUBSIDENCE TO THE E OF HI PRES BLDG INTO THE NRN PLAINS BRINGS MOCLR SKIES. DESPITE COLD NW FLOW THAT MIGHT RESULT IN SOME GUSTY WINDS THRU THIS AFTN...EXTENSIVE ICE COVER ON LK SUP AND THE STRONG SUBSIDENCE WL PREVENT ANY LK EFFECT SHSN. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 349 PM EST SAT MAR 1 2014 EXPECT NW WINDS UP TO 15 TO 25 KTS TO THE E OF HI PRES BUILDING INTO THE NORTHERN PLAINS TO DIMINISH TO UNDER 20 KTS AFTER MON NIGHT AS THE HI CENTER PASSES OVER THE UPPER GREAT LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLB AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
356 PM EST SAT MAR 1 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 349 PM EST SAT MAR 1 2014 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A PERSISTENT TROF OVER CANADA WITH CORE OF COLDEST AIR/CLOSED UPR LO OVER HUDSON BAY. 12Z H85 TEMPS UNDER THE LOWEST HGTS ARE AOB -30C...INDLUDING -30C AT INL AND -33C AT YPL. WITH A LLVL NW FLOW E OF ARCTIC HI PRES OVER THE CNDN PRAIRIES BLDG INTO THE NRN PLAINS...THIS COLD AIR IS ADVECTING INTO UPR MI. ALTHOUGH LATEST VSBL STLT IMAGERY SHOWS LK SUP IS MAINLY ICE COVERED...THERE ARE STILL SOME CLD/SHSN BANDS STREAMING INTO THE AREA AS THE UPSTREAM 12Z INL/YPL RAOBS SHOWED A RELATIVELY MOIST LLVL AIRMASS. BUT ANY PCPN HAS BEEN ON THE LGT SIDE...WITH EXTENSIVE ICE AND LLVL ACYC FLOW TENDING TO LIMIT THE INTENSITY OF THE SHSN. ONSET OF DAYTIME HEATING WITH INCRSG EARLY MARCH SUN ANGLE HAS ALSO RESULTED IN MORE INSTABILITY CU/SC OVER LAND AS WELL. SOME THICKER MID/HI CLDS ARE IMPACTING WI AND SRN UPR MI ON THE NRN FLANK OF DISTURBANCE/DEEPER MSTR TO THE S. SN UNDER SOME UPR DVGC IN RRQ OF 140KT H3 JET MAX STREAKING ACRS NRN MN/LK SUP IS AS FAR N AS SRN MN. MAIN FCST CONCERNS IN THE SHORT TERM ARE CLD TRENDS/CONTINUED BLO NORMAL TEMPS. TNGT...AS CNDN HI PRES CONTINUES TO BLD INTO THE NRN PLAINS...AN ACYC NW FLOW WL DOMINATE THE UPR LKS. ALTHOUGH SOME UPR DVGC ASSOCIATED WITH JET STREAK MOVING THRU THE UPR LKS WL PASS ACRS THE SCENTRAL THIS EVNG...GENERAL DRY ADVECTION IN THE H85-7 LYR SHOULD SUPPRESS NRN EDGE OF PCPN SHIELD TO THE S OF MENOMINEE. ALTHOUGH SOME LK CLDS/A FEW SN SHOWERS OFF LK SUP MAY LINGER UNDER THE COLD FLOW IN THE EVNG...LOSS OF DAYTIME HEATING AS WELL AS ACYC FLOW/ LOWERING SUBSIDENCE INVRN TOWARD 2K FT SHOWN ON FCST SDNGS SHOULD RESULT IN ALMOST COMPLETE SUPPRESSION OF CLDS/SN SHOWERS OVERNGT. WITH SKIES TURNING MOCLR AND PWAT UNDER 0.10 INCH...EXPECT SFC TEMPS TO TUMBLE AOB -20F AT MANY OF THE INTERIOR COLD SPOTS. GIVEN THE EXTENSIVE ICE COVER OF THE LK THAT WL TEND TO RESULT IN LOWER TEMPS OVER THE CWA...TRENDED TOWARD THE LO END OF GUIDANCE FOR MIN TEMPS FCST. LOWERING INVRN BASE/INCRSG STABILITY SHOULD KEEP SFC WINDS UNDER THE 10 MPH THRESHOLD FOR WIND CHILL HEADLINES...BUT ISSUED AN SPS TO HIGHLIGHT THE RESULTING VERY LO APRNT/WIND CHILL TEMPS THAT WL FALL AS LO AS -35F AT SOME PLACES. SUN...THERE WL BE A SHRTWV TRACKING SEWD TO THE NE OF UPR MI AND THRU ONTARIO...BUT BULK OF ASSOCIATED UPR FORCING WL REMAIN TO THE NE OF UPR MI. ALTHOUGH DAYTIME HEATING AND PASSAGE OF ATTENDANT WEAK SFC LO PRES TROF MAY RESULT IN SOME CLDS AND EVEN A FEW LGT SN SHOWERS MAINLY OVER THE NE HALF OF THE CWA TOWARD THE ACCOMPANYING DYANMIC FORCING...LO INVRN BASES SHOULD LIMIT THIS POTENTIAL. H85 TEMPS ARE FCST TO RANGE FM NEAR -20C OVER THE SCENTRAL TO AS LO AS -24C OR -25C OVER THE N. WITH THE EXTENSIVE ICE COVER...TEMPS WL REMAIN WELL BLO NORMAL DESPITE A GOOD DEAL OF SUNSHINE. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 439 AM EST SAT MAR 1 2014 CURRENT HIGHLY AMPLIFIED PATTERN FEATURING A STRONG RIDGE EXTENDING N THRU AK/YUKON AND A DEEP TROF DOWNSTREAM OVER MUCH OF CANADA INTO THE ADJACENT CONUS WILL BE BREAKING DOWN DURING THE LONG TERM. AS HAPPENED WITH THE LAST OCCURRENCE OF THIS HIGHLY AMPLIFIED PATTERN A FEW WEEKS AGO...THE NRN END OF THE WRN RIDGE IS STILL FCST TO CLOSE OFF AND RETROGRADE TO SIBERIA...ALLOWING PACIFIC FLOW TO STRENGTHEN INTO THE CONUS. THIS WILL RESULT IN SLOW MODERATION OF THE COLD DURING THE UPCOMING WEEK. HOWEVER...MEDIUM RANGE GUIDANCE CONTINUES TO SHOW A TENDENCY FOR SOME DEGREE OF WRN RIDGING WHICH SHOULD ENSURE BELOW NORMAL TEMPS PREVAIL ON MOST DAYS ACROSS UPPER MI DURING THE NEXT COUPLE OF WEEKS. PATTERN OVER THE NEXT 7 DAYS IS NOT REALLY FAVORABLE FOR MUCH IN THE WAY OF SYNOPTIC PCPN. HOWEVER... SHORTWAVES SWEEPING ONSHORE OFF THE PACIFIC AND TRACKING E IN A MORE PROGRESSIVE LOWER AMPLITUDE FLOW REGIME WILL BRING SOME OPPORTUNITIES FOR PCPN DURING THE MIDDLE AND END OF THE WEEK...BUT AT THIS TIME...NOTHING LOOKS SIGNIFICANT. NORMALLY WOULD BE DEALING WITH LES OFF LAKE SUPERIOR IN THIS LINGERING VERY COLD AIR MASS... BUT WITH EXTENSIVE ICE COVER THAT IS NEARING 100PCT...LES WILL ALMOST BE NONEXISTENT THRU THIS FCST PERIOD. BEGINNING SUN/MON...WHILE A SHORTWAVE SWINGING AROUND VORTEX IN THE VCNTY OF HUDSON BAY/NRN QUEBEC WILL BRUSH THE AREA SUN...AIR MASS IS TOO DRY TO SUPPORT ANY -SN...ESPECIALLY SINCE STRONGER FORCING PASSES BY TO THE N AND NE. IN ADDITION...WITH NEAR 100PCT ICE COVER ON LAKE SUPERIOR...THERE REALLY WON`T BE ANY LAKE COMPONENT. SINCE RATHER BRISK W TO NW WINDS WILL BE OCCURRING OVER THE LAKE...ICE MAY BE PUSHED ENOUGH TO EITHER MAINTAIN OR OPEN UP A LITTLE OPEN WATER ALONG THE IMMEDIATE MN N SHORE UP PAST ISLE ROYALE AND ALSO TO THE LEE OF THE KEWEENAW PENINSULA. IF SO...THERE WILL BE A FEW -SHSN OR FLURRIES...AND THUS SCHC POPS WILL BE UTILIZED IN THE AREAS FAVORED BY W TO NW WINDS. OTHERWISE...WILL CARRY DRY WEATHER ACROSS THE BOARD SUN AND ON INTO MON AS CANADIAN HIGH PRES SETTLES SE INTO THE PLAINS AND EXTENDS WEAK RIDGING INTO THE GREAT LAKES. TEMPS SUN/MON AFTN WILL STILL BE VERY COLD FOR THIS TIME OF YEAR EVEN THOUGH AIR MASS WILL BE SLOWLY MODERATING. EXPECT HIGHS IN THE SINGLE DIGITS TO AROUND 10F SUN AND A FEW DEGREES HIGHER FOR MON. SHOULD BE A BITTERLY COLD NIGHT SUN NIGHT UNDER MOSTLY CLEAR SKIES AS WINDS SHOULD DECOUPLE SUFFICIENTLY. A VERY DRY AIR MASS (PRECIPITABLE WATER JUST 15-20PCT OF NORMAL) WILL ENHANCE THE COOLING POTENTIAL. FAVORED MIN TEMPS AT OR BLO THE LOWEST GUIDANCE IN THE INTERIOR... ESPECIALLY AT TRADITIONAL COLD SPOTS WHICH SHOULD EASILY FALL WELL DOWN INTO THE -20S AND PERHAPS REACH -30F AT A LOCATION OR TWO. MON NIGHT INTO TUE...THERE REMAINS UNCERTAINTY IN WHETHER A WEAK SHORTWAVE MOVING ACROSS THE NRN ROCKIES AND THEN ESE WILL BRING SOME -SN TO THE AREA. THE ECMWF HAD BEEN GENERALLY FARTHER N...BUT THE 12Z TRENDED S...RESULTING IN DRY WEATHER HERE. THE 00Z RUN IS BACK TO BRUSHING THE AREA WITH SOME -SN. THE GFS AND GEM HAVE TRENDED N...AND BRING THE POSSIBILITY OF SOME -SN...ESPECIALLY THE GEM. WILL INCLUDE SCHC POPS ACROSS THE SW LATE MON NIGHT AND ACROSS MUCH OF THE AREA TUE. THERE MAY BE ENOUGH TIME BEFORE CLOUDS ARRIVE TO RESULT IN A QUICK TEMP DROP MON EVENING. LEANED TOWARD THE COLD SIDE OF GUIDANCE MON NIGHT...ESPECIALLY E WHERE CLOUDS WILL ARRIVE LATEST (-TEENS IN THE USUAL COLD SPOTS E). TEMPS TUE WILL RISE INTO THE TEENS. TUE NIGHT HAS THE POTENTIAL TO BE VERY COLD ONCE AGAIN AS THE CENTER OF STRONG HIGH PRES PASSES JUST TO THE N AND NE OF LAKE SUPERIOR. LIGHT WIND AND DRY AIR MASS WILL SUPPORT GOOD RADIATIONAL COOLING...ESPECIALLY OVER THE ERN FCST AREA WHERE COLUMN WILL BE DRIEST (PRECIPITABLE WATER 25PCT OF NORMAL). MINS IN THE USUAL COLD SPOTS OVER THE E SHOULD FALL INTO THE -TEENS. DRY WEATHER WILL CONTINUE INTO WED AS HIGH PRES CENTER DRIFTS E. E TO SE WINDS WON`T FAVOR MUCH OF A WARM UP OVER TUE. HIGH TEMPS WED SHOULD BE IN THE TEENS...COLDEST E CLOSER TO CORE OF COLDER AIR ASSOCIATED WITH HIGH. MEDIUM RANGE GUIDANCE FOR A FEW DAYS HAS BEEN INDICATING ONE OR TWO SHORTWAVES AFFECTING THE UPPER LAKES AT SOME POINT THU/FRI. FOR NOW...UTILIZED A SIMPLE CONSENSUS OF RECENT MODEL RUNS WHICH RESULTS IN SCHC/CHC POPS THU/FRI. TEMPS SHOULD RISE INTO THE 20S THU IN WAA REGIME AND MAY TOP OUT AROUND 30F FRI...DEPENDING ON TIMING OF FRONTAL PASSAGE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1225 PM EST SAT MAR 1 2014 EXPECT HI END MVFR TO VFR CONDITIONS THIS AFTN TO GIVE WAY TO JUST VFR WX THIS EVNG THRU SUN AS STRONG SUBSIDENCE TO THE E OF HI PRES BLDG INTO THE NRN PLAINS BRINGS MOCLR SKIES. DESPITE COLD NW FLOW THAT MIGHT RESULT IN SOME GUSTY WINDS THRU THIS AFTN...EXTENSIVE ICE COVER ON LK SUP AND THE STRONG SUBSIDENCE WL PREVENT ANY LK EFFECT SHSN. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 349 PM EST SAT MAR 1 2014 EXPECT NW WINDS UP TO 15 TO 25 KTS TO THE E OF HI PRES BUILDING INTO THE NORTHERN PLAINS TO DIMINISH TO UNDER 20 KTS AFTER MON NIGHT AS THE HI CENTER PASSES OVER THE UPPER GREAT LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...ROLFSON AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1228 AM EST SAT MAR 1 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 341 PM EST FRI FEB 28 2014 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW ARCTIC BRANCH WNW FLOW ALF OVER THE UPR LKS TO THE S OF CORE OF ARCTIC AIRMASS/CLOSED LO CENTERED OVER SRN HUDSON BAY. 12Z H5 TEMP WAS AS LO AS AN IMPRESSIVE -50C OVER NRN QUEBEC...AND -30C OR LOWER H85 TEMPS WERE PRESENT WITHIN THE CORE OF COLDEST AIR. A FAIRLY STRONG SHRTWV EMBEDDED IN THE ARCTIC BRANCH IS CURRENTLY JUST W OF LK WINNIPEG... WITH SUPPORTING AXIS OF STRONGER H3 WINDS AOA 100KT STRETCHING FM JUST S OF THE SHRTWV ACRS THE UPR LKS INTO NEW ENGLAND. SOME ENHANCED CLDS ARE PRESENT OVER THE NRN PLAINS INTO MN IN WHAT APPEARS TO BE THE RRQ OF SPEED MAX SUPPORTING THE LK WINNIPEG SHRTWV. THIS AREA IS ALSO EXPERIENCING GENERAL WAD/ISENTROPIC ASCENT IN THE SW FLOW AHEAD OF ACCOMPANYING H85 LO CENTER JUST S OF LK WINNIPEG. DESPITE QUITE A BIT OF VERY DRY LLVL AIR SHOWN ON LOCAL 12Z RAOBS...H925 DEWPT DEPRESSION WAS AS HI AS 26C AT MPX AT 12Z... SOME PATCHY LGT SN HAS BROKEN OUT OVER NE MN WHERE LATEST RUC ANALYSIS INDICATES SHARPER ISENTROPIC ASCENT/MOISTENING ON THE 270-280K SFCS /ABOUT H85-7/. DESPITE WHAT APPEARS TO BE FAIRLY EXTENSIVE ICE COVER ON VSBL STLT IMAGE OVER THE N PORTION OF LK MI...A BAND OF -SHSN IN THE LLVL SSW WIND UP THE LENGTH OF LK MOVED AS FAR N AS INTO MANISTIQUE BY LATE IN THE MRNG. ANOTHER BAND OF SN UNDER AXIS OF SHARPER MID LVL FGEN IS STREAKING ENEWD THRU WI TOWARD SCENTRAL UPR MI. OTRW...SFC TEMPS OVER UPR MI HAVE RECOVERED ABV ZERO FM THE RECORD COLD OBSVD THIS MRNG DESPITE THE THICKENING WAD CLDS. THE LOWEST TEMP REPORTED WAS -41F AT NEWBERRY CITY. MAIN FCST CONCERNS IN THE SHORT TERM WL BE SN TRENDS/POPS/GOING HEADLINES ASSOCIATED WITH SHRTWV/SFC LO NOW NEAR LK WINNIPEG. FOCUS FOR LATER TNGT INTO SAT TURNS TO TEMPS ONCE DRIER AIR RETURNS ALF AND ENDS THE PCPN. PER NCEP GUIDANCE AND ITS CONSISTENT HANDLING OF APRCHG DISTURBANCE...GENERALLY FOLLOWED THE 12Z GFS FOR FCST PREP. LATE THIS AFTN/TNGT...AREA OF DEEP LYR QVECTOR CNVGC/ISENTROPIC ASCENT ASSOCIATED WITH UPSTREAM SHRWTV IS FCST TO OVERSPREAD THE UPR LKS BY THIS EVNG BEFORE PUSHING OFF TO THE EAST AFT MIDNGT WITH VIGOROUS MID LVL DRYING/DEEP LYR QVECTOR DVGC FOLLOWING. EXPECT THE PATCHY LGT SN IN NRN MN EARLY THIS AFTN TO OVERSPREAD MOST OF UPR MI BY LATE AFTN. MODELS CONTINUE TO INDICATE THE WAD PCPN WL BE ENHANCED A BIT BY SOME UPR DVGC IN RRQ OF 120KT H3 JET MAX THAT IS SUPPORTING THE ENHANCED CLDS NOW OVER MN AND WHICH WL BE STREAKING EWD ACRS LK SUP AND INTO SE ONTARIO AFTER 00Z. LOOKS LIKE THE HEAVIEST PCPN WL FALL OVER THE SE HALF OF THE CWA CLOSER TO AXIS OF SHARPEST MID LVL FGEN AND WHERE THERE WL BE SOME ENHANCEMENT WITH LLVL SSW FLOW UP THE LENGTH OF LK MI...INCLUDING THE OPEN WATERS S OF THE LATITUDE OF MENOMINEE WHERE LES BAND WAS QUITE APRNT ON VSBL STLT IMAGERY BEFORE THE ARRIVAL OF HIER CLDS OBSCURED THIS FEATURE. THE ARRIVAL OF THE MID LVL DRYING/DEEP LYR QVECTOR DVGC WL END OVERALL LIGHTER PCPN OVER THE W EARLY THIS EVNG AND OVER THE E SOON AFT 06Z. AS FOR SN TOTALS...H7 SPECIFIC HUMIDITY IS FCST TO INCRS TO 1.5-2.0 G/KG OVER THE SE CWA AT 00Z. WITH A 6HR PERIOD OF SYNOPTIC SN AT MOST LOCATIONS...THAT WOULD EQUATE TO UP TO 2 INCHES OF ACCUM. BUT FCST SDNGS CONT TO EXHIBIT A DEEP DGZ THAT IS 10K FT OR EVEN DEEPER. WITH FVRBL SN/WATER RATIOS THAT MAY BE AS HI AS 25-30:1... EXPECT UP TO 4 INCHES SN TOTAL OVER MUCH OF THE SE CWA WHERE DYNAMIC SUPPORT WL BE GREATEST. WITH SOME ENHANCEMENT OFF LK MI THAT MIGHT ADD AN ADDITIONAL INCH OR 2 TO THE SN TOTALS...GOING ADVYS FOR DELTA/SRN SCHOOLCRAFT COUNTIES STILL SEEM ON TARGET. AFTER THE PCPN ENDS...A DVLPG NW FLOW IN THE WAKE OF THE SFC LO CENTER TRACKING ACRS LK SUP WL ADVECT COLDER AIR BACK INTO THE UPR LKS...DROPPING H85 TEMPS TO ARND -25C OVER THE NW BY 12Z SAT. WITH EXTENSIVE ICE COVER ON LK SUP...ANY LK EFFECT SHSN IN THE NW WIND SN BELTS SHOULD BE NO MORE THAN ISOLD. SO MAINTAINED ONLY SCHC POPS IN THESE LOCATIONS. THE REST OF THE CWA WL BE DRY AFT THE EVNG PCPN EXITS. ONE CONCERN IS THE POTENTIAL FOR ADVY LVL WIND CHILLS OVER THE W LATER ON. PREFER THE SOMEWHAT STRONGER WINDS SHOWN BY THE FAVORED GFS...WHICH HAS CONSISTENTLY SHOWN A DEEPER SFC LO TRACKING ACRS LK SUP. BUT EVEN THE HIER GFS NW WINDS AND FCST MIN TEMPS CLOSE TO -10F OVER THE W RESULT IN ONLY MARGINAL WIND CHILLS NEAR -25F LATE TNGT INTO SAT MRNG. SO OPTED TO HOLD OFF ON ADVY FOR NOW. SAT...THE CWA WL BE DOMINATED BY COLD...ACYC NW FLOW E OF ARCTIC HI PRES BLDG INTO THE NRN PLAINS. H85 TEMPS ON SAT ARE FCST TO FALL TO -29C OVER THE NW TO -25C OVER THE SE CWA BY 00Z SUN. OVERALL ACYC FLOW AND NEAR ABSENCE OF OPEN WATER OVER LK SUP SHOULD RESTRICT LES POPS TO NO HIER THAN LO CHC. GUSTY NW WINDS WITH UNSTABLE LLVL LAPSE RATES UP TO INVRN BASE NEAR H85 WL ALLOW FOR SOME BLSN MAINLY IN OPEN AREAS NEAR LK SUP DOWNWIND OF SNOW COVERED ICE THAT HAVE BEEN PLAGUED BY THESE EVENTS THRU THIS COLD WINTER. BUT SINCE LTL IF ANY SN WL BE FALLING...SUSPECT THERE WL BE NO SGNFT ISSUES. GIVEN THE ANOMALOUSLY COLD H85 TEMPS...TENDED TOWARD THE LOWER END OF GUIDANCE FOR MAX TEMPS...WHICH ARE SUPPORTED BY MIXING TO H85 ON THE GFS FCST SDNGS. WITH DISTURBANCE STREAKING E TOWARD THE LOWER LKS...NOT OUT OF THE QUESTION THE NRN FRINGE OF -SN SHIELD COULD BRUSH THE FAR SCNTRL LATE IN THE DAY. RETAINED SCHC POPS THERE. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 436 PM EST FRI FEB 28 2014 BY EARLY NEXT WEEK...MODELS POINT TOWARD A BREAK IN THE HIGHLY AMPLIFIED WEST COAST/ERN PACIFIC RIDGE AND BROAD DOWNSTREAM TROUGH PATTERN WHICH HAS CHARACTERIZED MUCH OF OUR RECORD COLD WINTER. MODELS INDICATE THAT THE NRN END OF THE WRN RIDGE IS FCST TO CLOSE OFF AND RETROGRADE TO SIBERIA...ALLOWING PACIFIC FLOW TO STRENGTHEN INTO THE CONUS. THIS WILL BRING ABOUT A SLOW MODERATION IN TEMPS FOR NEXT WEEK. HOWEVER...MEDIUM RANGE GUIDANCE CONTINUES TO SHOW A TENDENCY FOR SOME DEGREE OF WRN RIDGING WHICH SHOULD ENSURE GENERALLY BELOW NORMAL TEMPS PERSIST ACROSS UPPER MI FOR THE FIRST COUPLE OF WEEKS OF MARCH. SYNOPTIC PCPN APPEARS TO BE MININAL IN THIS PATTERN WITH THE BEST CHANCE FOR PCPN MID TO LATE WEEK AS A SERIES OF SHORTWAVES MOVE ONSHORE FROM THE PACIFIC AND TRACK E ACROSS THE NRN CONUS IN A MORE LOWER AMPLITUDE MORE PROGRESSIVE FLOW. LINGERING COLD AIRMASS FOR LATE THIS WEEKEND INTO EARLY NEXT WEEK WOULD NORMALLY RESULT IN LES OFF LAKE SUPERIOR IN NW FLOW... BUT GIVEN NEAR 100PCT ICE COVER...LES MAY BE SHUTDOWN THRU THIS FCST PERIOD. SAT NIGHT INTO MONDAY...A HIGH PRES RIDGE STRETCHING FROM THE SFC HIGH CENTER OVER THE NRN PLAINS INTO THE UPPER LAKES WILL ENSURE A PERIOD OF DRY...BUT STILL VERY COLD WEATHER SAT NIGHT INTO SUNDAY NIGHT. FORECASTING TEMPS WILL BE A CHALLENGE FOR SAT NIGHT INTO EARLY NEXT WEEK AS MIN TEMPS COULD BE VERY COLD EACH NIGHT (WELL BLO LOWEST GUIDANCE) UNDER LINGERING BUT GRADUALLY MODERATING ARCTIC AIR MASS. HIGH CLOUDS ON THE NRN FRINGE OF DISTURBANCE PASSING TO THE S OF THE AREA MAY LIMIT COOLING SOME SAT NIGHT. OTHERWISE...CLOUD COVER MAY NOT BE THAT MUCH OF AN ISSUE THRU EARLY NEXT WEEK AS BUILDING HIGH PRESSURE SHOULD ENSURE MOSTLY CLEAR SKIES AND THERE SHOULD BE LITTLE IF ANY STRATOCU OFF WHAT SHOULD BE A TOTALLY ICE COVERED LAKE SUPERIOR. EXPECT WINDS TO BE MOSTLY LIGHT EACH NIGHT AS SFC HIGH PRES DOMINATES SO WILL CONTINUE TO FAVOR MIN TEMPS GENERALLY AT OR BLO THE LOWEST GUIDANCE SAT NIGHT AND SUN NIGHT...ESPECIALLY FOR TRADITIONAL COLD SPOTS. WITH MODELS TRENDING FARTHER SOUTH WITH SHORTWAVE NOW FCST TO MOVE THROUGH THE NORTHERN PLAINS AND LOWER MIDWEST...CLOUDS MAY NOT BE AS MUCH OF A FACTOR AS PREV THOUGHT SO HAVE TRENDED COLDER WITH MIN TEMPS FOR MON NIGHT...CLOSER TO GEM-NH BIAS CORRECTED VALUES. INCREASINGLY HIGHER SUN ANGLE AT THIS TIME OF YEAR WORKING ON LOWER ALBEDO FORESTED TERRAIN WILL HELP TEMPS REBOUND INTO THE SINGLE DIGITS AND LOWER TEENS ABOVE ZERO FROM FRIGID OVERNIGHT LOWS EACH DAY...THOUGH MAX TEMPS WILL STILL BE WELL BLO NORMAL. 12Z MODELS NOW SHOWING BIGGER DISCREPANCIES FOR MID TO LATE NEXT WEEK. BOTH THE GEM-NH AND ECMWF AND TO A LESSER EXTENT THE UKMET SHOW A SHORTWAVE ROTATING DOWN FM HUDSON BAY BRINGING ANOTHER PUSH OF ARCTIC AIR INTO THE REGION. THE GEM-NH IS DEEPER AND SLOWER WITH THIS FEATURE THAN THE ECMWF AND EVENTUALLY FORMS A CLOSED LOW BY 12Z THU OVER THE WRN GREAT LAKES. MEANWHILE THE GFS SHOWS THIS SHORTWAVE STAYING WELL NE AND NOT IMPACTING THE GREAT LAKES. GIVEN UNCERTAINTY...FEEL INCLINED TO FOLLOW ALONG WITH THE ECMWF WHICH IS MORE OF A COMPROMISE BETWEEN THE GFS AND MORE EXTREME GEM-NH SOLN. THIS WILL KEEP MORE OF AN ARCTIC AIRMASS OVER THE AREA FOR ONE MORE DAY WITH DOUBLE DIGIT BELOW ZERO TEMPS POSSIBLE AGAIN ON TUE NIGHT BEFORE AIRMASS BEGINS TO MODERATE ON WEDNESDAY. MODELS STILL SHOW A PACIFIC SHORTWAVE COMING INTO THE AREA TOWARD THE END OF THE WEEK WITH SIGNIFICANT TIMING ISSUES. THE GFS IS MUCH MORE PROGRESSIVE BRINGING THE SHORTWAVE AND ASSOC FRONT THROUGH THU AFTERNOON AND EVENING WHILE THE ECMWF DOES NOT BRING IT THROUGH UNTIL LATE THU NIGHT AND FRI. FOR NOW WILL FOLLOW CONSENSUS MODEL GUIDANCE RESULTING IN 30 TO 40 PCT POPS FOR LIGHT SNOW MAINLY THU NIGHT INTO FRI. TEMPS BY THE END OF THE WEEK WILL MODERATE INTO THE 20S AND MAY EVEN APPROACH 30F AT A FEW SITES ALONG THE WI BORDER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1228 AM EST SAT MAR 1 2014 MVFR/VFR CONDITIONS EXPECTED EARLY THIS AM AS LINGERING SNOW SHOWERS WANE WITH INCREASING SUBSIDENCE AND DRIER AIR MOVING IN. MVFR CIGS TO LINGER THROUGH SAT MRNG AT IWD/CMX WITH STEADY... UPSLOPE NW FLOW OF COLDER AIR. EXTENSIVE ICE COVER OVER LAKE SUPERIOR WILL LIMIT THE POTENTIAL FOR HEAVIER LES THAT WOULD NORMALLY BE A PROBLEM AT THESE LOCATIONS. DOWNSLOPE NW FLOW SHOULD RESULT IN PREDOMINANTLY VFR CONDITIONS AT SAW. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 436 PM EST FRI FEB 28 2014 EXPECT S WINDS UP TO 20-25 KTS AHEAD OF LO PRES CROSSING LAKE SUPERIOR THIS EVENING TO SHIFT TO THE NW LATE TONIGHT ONCE THE LO SHIFTS INTO SE ONTARIO AND THEN INCREASE UP TO 25-30 KTS INTO SAT UNDER SHARPENING PRES GRADIENT BETWEEN THE DEPARTING LO AND HI PRES BUILDING INTO THE NORTHERN PLAINS. A RIDGE BUILDING ACROSS THE GREAT LAKES FROM THE N PLAINS AND S CENTRAL CANADA SATURDAY THROUGH MONDAY WILL ENSURE LIGHT WINDS. HIGH PRESSURE AND GENERALLY LIGHT WINDS WILL CONTINUE TO DOMINATE THE UPPER GREAT LAKES INTO THE MIDDLE OF NEXT WEEK. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY UNTIL 1 AM EST EARLY THIS MORNING FOR MIZ014. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...VOSS AVIATION...JLB/RJT MARINE...KC/VOSS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1041 PM CST Fri Feb 28 2014 .UPDATE: Issued at 817 PM CST Fri Feb 28 2014 Going forecast looks on track. Radar continues to show weak returns over central and southeast Missouri with high dewpoint depressions and no precipitation reports on the surface observations. Will maintain slight chances for rain and snow for these returns which are being forced by weak moisture convergence that shows up well in the RAP. RAP also shows that precipitation now over northwestern MO will continue to move east and reach the northern CWA after midnight. Britt && .SHORT TERM: (Through Late Tonight) Issued at 351 PM CST Fri Feb 28 2014 (Tonight) System currently over the south-central United States and its attendant precipitation shield is forecast to continue to weaken as it slowly travels to the north and east. Main impact across our CWFA will be increasing mid/high level cloudiness. Did keep slow low chc PoPs in case some light rain showers do hold together over portions of south-central and southeastern Missouri early this evening. Also kept chc PoPs over portions of northeastern Missouri and west-central Illinois roughly along arctic baroclinic zone. For temperatures...leaned warmer ahead of boundary overnight tonight due to expected cloud cover and southerly component to winds. Gosselin .LONG TERM: (Saturday through Next Friday) Issued at 351 PM CST Fri Feb 28 2014 Saturday through Monday: Upper shortwave ridging moves across the area tomorrow, ensuring quiet conditions through at least the morning hours and probably for most of the afternoon as well. Attention then turns to a potentially high-impact late winter storm which is expected to bring a veritable cornucopia of precipitation types to the LSX CWA this weekend, especially from Saturday night through Sunday night. The overall thinking remains similar to previous forecast packages: snow in the north (including KUIN/KHAE), freezing rain in the south (including KFAM), a band of mixed precip in the middle (including KCOU, KSTL, KSLO), and a gradual changeover with time from mixed ptypes to pure snow after colder air moves into the region. The primary forecast issues are precipitation types and amounts, although forecasting these details is difficult since neither the main system nor its leading shortwaves have been sampled by the upper air network. Regardless, all guidance suggests that the specific amounts of each precipitation type are far less important than the cumulative effects of a widespread and prolonged wintry mix over the region. No changes were made to the ongoing Winter Storm Watch at this time due to continued uncertainty regarding precipitation types and amounts. Atmospheric features that will affect ptypes and amounts during this event include 1) a sharpening baroclinic zone to the south of the CWA, 2) an Arctic air mass spreading across the area from the north, 3) a warm nose aloft associated with a LLJ, 4) several hours where the maximum lift occurs just below or within the DGZ in an environment which is saturated WRT ice, and 5) a secondary DGZ which develops below 5000 ft on Sunday and may re-introduce ice crystals at low levels. This forecast package reflects a blend of several models excluding the SREF, which was discounted because it was much warmer and farther north than any other guidance. Precipitation will probably begin as snow in the north and rain or freezing rain farther south, depending on surface temperatures. A prolonged period of sleet (occasionally mixing with rain, freezing rain, and/or snow depending on the location) is expected across a broad part of the CWA. One of the factors contributing to the prolonged period of sleet is that as the depth of the surface cold layer gradually increases to 3000-4000 ft, the strength of the warm nose aloft will become less important since partially or fully melted snowflakes will have plenty of time and distance to refreeze into ice pellets. In general, precipitation types should change from ZR -> ZR/IP -> IP -> IP/SN -> SN. Isolated thunder is possible on Sunday, which would tend to increase precipitation rates. The greatest snow accumulations are expected across northeast MO/west central IL and the greatest ice accumulations are expected across southern and southeastern MO into southern IL. 1020-1030 hPa surface high builds into the region on Monday behind the departing system with unseasonably cold air returning to the area. Kanofsky Tuesday through Friday: Very cold ams in the wake of the weekend storm will mean more unusually cold early March weather lingering into Tuesday. All of the latest raw model output and MOS-based guidance are indicating single digits lows in the offing for the entire CWA on Tuesday morning, with highs rebounding into the lower 20s to lower 30s during the afternoon hours. Heading into the latter half of the week, mean UA flow over the CONUS takes on a much more zonal look, which should translate into moderating temperatures. Operational GFS is forecasting a very big warmup by Thursday, however the ECMWF, GEM, and to a lesser extent the GFS ensemble keep heights much lower over the northeast U.S., which in turn keeps surface ridge entrenched from the Great Lakes into the mid Mississippi Valley and slows the ewd erosion of the cold air. Given the snow cover that should be blanketing much of the region, as well as the cold track record of this winter, have used with model consensus and gone with a slower warming trend, with temps finally rebounding to near normal levels by Friday. Precipitation threat looks fairly low for much of the extended period. All medium range models to forecast shortwave to pass over the area Wed-Wed night, but with surface ridge nosing into area moisture should be modest so have kept PoPs in the slight chance range for now. Truett && .AVIATION: (For the 06z TAFs through 06z Saturday Night) Issued at 1014 PM CST Fri Feb 28 2014 Low level cloud cover around 3000-6000 ft which has advected into COU should continue spreading ewd into the rest of the taf sites around or shortly after 06z Saturday. A cold front extending from just north of UIN to just southeast of MCI will drop sewd through UIN and COU just after 06z Saturday, and through the St Louis metro area around 12z Saturday with the wind veering around to a n-nwly direction and strengthening after fropa. The cloud ceiling will lower into the MVFR catagory after fropa as well. A narrow band of precipitation along this front across nwrn MO will move through UIN late tgt. This precipitation band may weaken some as it gets further east, but should lead to a brief period of light rain/snow in UIN, possibly mixed with sleet. Heavier and more widespread precipitation should move into the area Saturday evng as a s-swly low level jet brings strong low-mid level warm air advection and increasing low level moisture to the region. Precipitation type is uncertain but should be mainly snow in UIN, and freezing rain and sleet at the other taf sites. The cloud ceiling may also lower into the IFR catagory as well. Specifics for KSTL: S-sely surface winds will veer around to a swly direction late tgt. The surface wind will continue to veer around to a n-nwly direction early Saturday mrng after fropa and strengthen through the day and into Saturday evng. VFR, low level clouds will advect into STL just after 06z Saturday, and lower into the MVFR catagory Saturday mrng after fropa. Precipitation should move into the STL area by late Saturday evng. Precipitation type is uncertain but will likely be freezing rain and sleet. The cloud ceiling will lower into the IFR catagory Saturday evng as well. GKS && .CLIMATE: Issued at 351 PM CST Fri Feb 28 2014 Potentially historically cold arctic air is forecast to move into the region beginning on Sunday and lasting into Tuesday. Several records are in jeopardy of being broken at our three official climate sites which can be seen below: St. Louis, MO (1874-present): Date Record low Record low maximum 3/2 2 (1980) 19 (1943) 3/3 1 (1943) 19 (2002) 3/4 -1 (1978) 15 (1960) Columbia, MO (1890-present): Date Record low Record low maximum 3/2 -5 (1890) 17 (1943) 3/3 1 (1900) 16 (2002) 3/4 -5 (1978) 12 (1960) Quincy, IL (1901-present): Date Record low Record low maximum 3/2 -2 (1980) 21 (1960) 3/3 -1 (1913) 14 (2002) 3/4 -8 (1978) 11 (1960) && .LSX WATCHES/WARNINGS/ADVISORIES: MO...WINTER STORM WATCH from Saturday evening through late Sunday night FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Knox MO- Lewis MO-Lincoln MO-Madison MO-Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Reynolds MO- Shelby MO-St. Charles MO-St. Francois MO-St. Louis City MO- St. Louis MO-Ste. Genevieve MO-Warren MO-Washington MO. IL...WINTER STORM WATCH from Saturday evening through late Sunday night FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL- Fayette IL-Greene IL-Jersey IL-Macoupin IL-Madison IL- Marion IL-Monroe IL-Montgomery IL-Pike IL-Randolph IL-St. Clair IL-Washington IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
600 PM CST SUN MAR 2 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 430 PM CST SUN MAR 2 2014 ...RECORD OR NEAR-RECORD LOW TEMPERATURES AROUND DAYBREAK TOMORROW IN THE COLDEST START TO MARCH SINCE 2002 AND ONE OF THE COLDEST STARTS ON RECORD... ALOFT: MODESTLY SPLIT LOW-AMPLITUDE FLOW WAS OVER THE CONUS WITH A SHORTWAVE TROF MOVING E THRU CO/NM INTO INCREASINGLY CONFLUENT FLOW. THIS TROF WILL HEAD E ACROSS THE SRN PLAINS AND INTO THE SE STATES TONIGHT. AS THIS OCCURS...HEIGHTS WILL RISE OVER THE WRN USA. HOWEVER...THE NEXT SHORTWAVE TROF IS MOVING ONSHORE INTO OR/NRN CA THIS AFTERNOON. THE MOST INTENSE PORTION OF THIS TROF WILL MISS THE REGION FAR TO THE NW...BUT A LOW-AMPLITUDE PV STREAMER WILL MOVE THRU TOMORROW...WEAKENING AS IT MOVES THRU THE RIDGE. SURFACE: ELONGATED AND UNSEASONABLY STRONG HIGH PRES EXTENDED FROM WRN CANADA S INTO THE PLAINS. THIS HIGH WILL SHRINK AND SLOWLY WEAKEN AS IT DRIFTS INTO THE MIDWEST TONIGHT...AND INTO THE GREAT LAKES TOMORROW. THIS HIGH AND CLOUD COVER WILL PLAY MAJOR ROLES IN HOW COLD TEMPS GET TONIGHT. BREAKING/SETTING RECORD LOWS IS ON THE TABLE. REST OF THIS AFTERNOON: CLOUDY BUT SOME IMPROVEMENT WILL ENCROACH FROM THE N OF NEB HWY 92. SOME LIGHT SNOW /-SN/ MAY DEVELOP OVER PARTS OF S-CNTRL NEB. TEMPS DID GET ABOVE THE ALL-TIME RECORD COLDEST FOR THE MONTH OF MARCH...BUT NOT BY MUCH. PLEASE SEE THE CLIMATE SECTION FOR ADDITIONAL INFO ON RECORDS. TONIGHT: UNSEASONABLE BITTER COLD! IF OUR TEMPS WORK OUT AS FCST... LOWS WILL BE NEARLY 40F COLDER THAN WHERE THEY TYPICALLY ARE FOR EARLY MARCH /LOW-MID 20S/. THE PASSAGE OF THE TROF TONIGHT WILL RESULT IN A DECREASING CLOUDS. SOME MULTI-LAYERED MID-HIGH CLOUDS ARE UPSTREAM OVER WY...BUT THEY WILL BE MOVING INTO SUBSIDENCE. SO AM NOT EXPECTING SKIES TO COMPLETELY CLEAR...BUT IT SHOULD BE ENOUGH TO INFLICT A MAJOR IMPACT ON TEMPS. THE SURFACE RIDGE AXIS WILL MIGRATE ACROSS THE FCST AREA AS WELL... RESULTING IN SEVERAL HOURS OF CALM OR NEARLY CALM WINDS. TEMPS: LOWS WERE -13 TO -20 OVER THE DAKOTA`S THIS MORNING. AND WHILE THERE IS SNOWCOVER UP THERE...MOST OF IT IS A WEEK OLD. THE OTHER THING TO CONSIDER IS THE MAGNITUDE OF THIS AIR MASS. THE 850 MB TEMP WAS -21C AT GRAND ISLAND THIS MORNING. BASED ON REANALYSIS DATA...-21 AND COLDER HAS ONLY OCCURRED 4 TIMES IN THE PAST 34 YRS. AND GIVEN THAT TEMPS WILL ONLY BE ABOVE FRZG FOR ABOUT 5 HRS TODAY ALONG AND N OF HWY 6...I BELIEVE WE NEED TO FCST RECORD COLD. DEWPOINTS ARE ALSO IN THE NEGATIVE TEENS OVER MUCH OF S-CNTRL NEB. LOW TEMPS WERE DROPPED 4-7F FROM THE PREVIOUS FCST. A WIND CHILL /WC/ ADVISORY WAS ISSUED FOR MOST OF THE FCST AREA. FROM THE TRI-CITIES N AND E...A WARNING WAS ISSUED FOR 1-2 HRS OF -30 TO -35 WC`S IN THE 6AM-9AM TIMEFRAME. JUST AS TEMPS BOTTOM OUT...WINDS WILL BEGIN TO INCREASE AND THIS WILL HAPPEN DURING THE MORNING RUSH. SNOW: A NICE BAROCLINIC LEAF HAS DEVELOPED ON SATELLITE WITH A BLOSSOMING AREA OF DEFORMATION -SN OVER WRN KANSAS. THIS HAS DEVELOPED FURTHER N THAN THE 12Z NAM-DERIVED HI-RES MODELS FCST. THE 17Z HRRR HAS IT AND BELIEVE THERE IS A WINDOW OF OPPORTUNITY FOR A TOUCH OF -SN OVER PARTS OF N-CNTRL KS...ESPECIALLY FROM STOCKTON-OSBORNE-BELOIT SOUTHWARD. A CHANCE OF -SN IS NOW IN THE FCST. THE MID-LEVEL CIRCULATION IS FCST TO DROP ESE WHICH WILL ACTUALLY DRAG THE SNOW SHIELD AWAY FROM N-CNTRL KS AS SUNSET APPROACHES. TOMORROW: HIGH CLOUDS WILL ALREADY BE MOVING IN AT DAWN ASSOCIATED WITH THE WEAK UPPER TROF. SO OVERALL EXPECT A PARTLY SUNNY AND BLUSTERY DAY. HOW QUICKLY TEMPS WARM UP IS UNCERTAIN. SO CONFIDENCE IN THE HOURLY TEMPS IS BELOW AVERAGE. WENT ABOVE NEARLY ALL GUIDANCE ON WIND SPEEDS. AS A LEE-SIDE TROF DEVELOPS...THE PRES GRADIENT WILL INCREASE TO 16 MB ACROSS NEB. THE GFS/EC/NAM/SREF HAVE A 30-35 KT LOW-LEVEL JET MAX AND BELIEVE WE WILL TAP INTO THE UNDERSIDE OF IT. MIXING HEIGHTS ARTIFICIALLY TOO LOW...ESPECIALLY ON THE NAM WHICH HAS ITS SNOWCOVER BIAS. EVEN IF WE USE THE CONSERVATIVE GFS MIXING HEIGHTS AROUND 2K FT...THAT STILL WOULD ALLOW FOR MIXING DOWN 30 KTS. HIGH TEMPS WERE RAISED 2-4F FROM THE PRIOR GID FCST...ALONG AND W OF HWY 281. POST MORTEM: LAST NIGHT`S SNOW RISK OVER CNTRL/NRN KS ENDED UP CONSIDERABLY LESS THAN WHAT THE MODELS DEPICTED. THESE TYPE OF SITUATIONS THAT ARE DRIVEN BY JET STREAK AND FRONTAL FORCING /IN THE MID-LEVELS/ ARE INCREDIBLY DIFFICULT TO FCST. THERE IS NO LOW PRES FROM WHICH WE DERIVE OUR TRADITIONAL FCST CUES. THESE ISOLATED NARROW SNOW BANDS HAVE VERY LOW PREDICTABILITY. THE HI-RES MESOSCALE MODELS DEPICT THEM VERY WELL /WHEN AND IF THEY ARE CORRECT/. YOU CAN THROW OUT THE SYNOPTIC SCALE MODELS. THEY CANT HANDLE THESE SMALL FEATURES AND ARE WAYYYY TO BROAD WITH THEIR QPF. THE BAND DID DEVELOP BUT IT WAS MODELED TO BECOME STATIONARY ALONG/NEAR I-70 WHICH IT DID NOT. IT WAS TRANSIENT. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 430 PM CST SUN MAR 2 2014 ALTHOUGH THERE HAVE BEEN NO MAJOR CHANGES TO THE FORECAST DURING THIS TIME FRAME OVER THE PAST 12-24 HOURS...AS IS TYPICAL SEVERAL PERIODS HAD HIGH/LOW TEMPS TWEAKED UPWARD OR DOWNWARD AS MUCH AS 2-5 DEGREES...BUT THE OVERALL THEME OF A TRANSITION TO MILDER WEATHER REMAINS INTACT. THAT BEING SAID...ITS NOT NECESSARILY GOING TO BE A CASE WHERE EACH DAY GETS PROGRESSIVELY WARMER...AS DAYS SUCH AS WEDNESDAY...FRIDAY AND POSSIBLY SATURDAY COULD END UP BEING EITHER SMALL OR POTENTIALLY LARGER BUMPS IN THE ROAD. MEANWHILE...BOTH THURSDAY AND VERY PRELIMINARILY NEXT SUNDAY BOTH LOOK LIKE THE BEST CANDIDATES FOR THE MILDEST DAYS OF THE NEXT 7 WITH ABOVE NORMAL READINGS BETWEEN THE UPPER 40S-LOW 60S. PRECIPITATION-WISE...THE MAJORITY OF THIS 6-DAY PERIOD SHOULD BE DRY...BUT 20-30 POPS CONTINUE FOR ALL OR PARTS OF THE CWA ON TUESDAY NIGHT-WEDNESDAY AND FRIDAY NIGHT...AND A NEW SLIGHT CHANCE HAS BEEN ADDED TO NORTHERN ZONES FRIDAY DAYTIME...MAKING NOW A TOTAL OF 4 PERIODS MENTIONING SOME RISK OF MEASURABLE PRECIP. NEEDLESS TO SAY...UNCERTAINTY REMAINS HIGH IN BOTH OF THESE WINDOWS OF OPPORTUNITY FOR PRECIPITATION...INCLUDING THE TUES NIGHT-WED POSSIBILITY. FOR ONLY BEING A FEW DAYS AWAY...ITS STILL TOUGH TO SAY WHETHER 1) THERE IS EVEN MUCH CHANCE OF MEASURABLE PRECIP AT ALL AND HENCE POPS KEPT LOW THUS FAR AND 2) IF PRECIP DOES FALL...WHAT TYPE WILL IT ASSUME? KEEPING WITH THE REASONING DISCUSSED HERE 24 HOURS AGO...HAVE KEPT ANY TUES-NIGHT WED PRECIP TYPE AS SNOW OR RAIN/SNOW FOR NOW...BUT THERE CONTINUES TO BE SIGNS IN SOME FORECAST SOUNDINGS THAT AT LEAST A BRIEF PERIOD OF SLEET/SOME TYPE OF WINTRY MIX COULD COME INTO PLAY HERE AS WELL. GIVEN TIME IS STILL ON OUR SIDE HERE WITH THIS POSSIBLE ROUND OF PRECIP STILL BEING 48+ HOURS AWAY...WILL KEEP THE BASIC TYPES FOR NOW AND AVOID CLUTTERING THE FORECAST WITH TOO MUCH UNCERTAINTY AND/OR CAUSING UNDUE CONCERN AS THE MENTION OF MIXED-PHASE WINTRY TYPES CAN SOMETIMES DO. AS FOR POTENTIAL SNOWFALL AMOUNTS WITH ANY TUES NIGHT/WEDNESDAY PRECIP...ITS OBVIOUSLY WAY TOO EARLY TO TALK SPECIFICS WITH MUCH CONFIDENCE...BUT GIVEN THAT IT IS WITHIN 72 HOURS OF NOW HAVE TOSSED A VERY GENERIC COVERAGE OF AMOUNTS RANGING FROM A DUSTING UP TO AROUND 1 INCH INTO THE OFFICIAL SNOWFALL GRIDS. THE SAME SNOW OR RAIN/SNOW PRECIP TYPE ROUTE WAS USED WITH THE FRIDAY-FRIDAY NIGHT POPS...ALTHOUGH THE LATEST ECMWF WOULD SUGGEST THIS WOULD PROBABLY BE MORE OF A TRUE SNOW EVENT WITH LESS RISK OF MIXED-TYPES SHOULD IT OCCUR. GETTING INTO MORE DETAIL AND STARTING WITH MONDAY NIGHT...CONFIDENCE IS PRETTY HIGH IN DRY CONDITIONS WITH ONLY SOME PASSING MID-HIGH LEVEL CLOUDS AS THE CENTRAL PLAINS REMAINS UNDER A BROAD WEST-NORTHWEST FLOW REGIME ALOFT THAT DEFINES MUCH OF THE CONUS. THERE ARE SOME HINTS THAT SOME LOWER STRATUS COULD DEVELOP AND STREAM NORTHWARD INTO PARTS OF THE CWA IN LOW LEVEL SOUTHERLY FLOW...BUT AM NOT SOLD ON THIS SCENARIO SO SKY COVER IS GENERALLY AIMED INTO PARTLY CLOUDY TERRITORY FOR NOW. SOUTHERLY BREEZES OF AT LEAST 5-10 MPH WILL PREVAIL THROUGH THE NIGHT...AND AS A RESULT LOW TEMPS SHOULD REMAIN CONSIDERABLY HIGHER THAN THOSE ON MONDAY MORNING BUT STILL WELL BELOW NORMAL. MADE LITTLE CHANGE TO THESE VALUES...STILL AIMING FOR MOST OF THE CWA TO BOTTOM OUT SOMEWHERE BETWEEN 9-14 ABOVE ZERO. FOR TUESDAY DAYTIME THROUGH WEDNESDAY NIGHT...THE OVERALL STORY IN THE MID-UPPER LEVELS INVOLVES THE GRADUAL EAST-SOUTHEASTWARD DEVELOPMENT OF A PROGRESSIVE SHORTWAVE TROUGH THAT MOVES FROM THE PACIFIC COAST INTO THE CENTRAL AND ESPECIALLY SOUTHERN PLAINS...AMPLIFYING AS IT DOES SO. WITH THE MAIN BATCH OF FORCING STILL WEST OF THE AREA DURING THE DAY TUESDAY HAVE KEPT IT DRY...AND EVEN RAISED TEMPS 2-4 DEGREES GIVEN CONTINUED SOUTHERLY FLOW AHEAD OF A COLD FRONT THAT STARTS TO DROP INTO NORTHERN ZONES IN THE AFTERNOON. ASSUMING THAT CLOUDS ARE NOT OVERLY ABUNDANT...ITS POSSIBLE THAT ADVERTISED HIGHS RANGING FROM MID 30S NORTHEAST TO MID 40S SOUTHWEST MAY NOT BE WARM ENOUGH...BUT ITS ALSO WORTH NOTING THAT THE HIGHS ADVERTISED BY THE LAST FEW NAM RUNS APPEAR WAY TOO COLD. TUESDAY NIGHT INTO WEDNESDAY...MODEL TIMING DIFFERENCES GROW...BUT VARIOUS MODELS INCLUDING THE NAM/GFS/ECMWF BRING AT LEAST LIGHT PRECIP OF AT LEAST SOME VARIETY INTO THE AREA BEFORE MOVING IT OUT BY WEDNESDAY NIGHT. THE MILLION DOLLAR QUESTION IS HOW STRONG THE SYNOPTIC FORCING/FRONTOGENESIS WILL BE WITH THIS WAVE OVER THE LOCAL AREA...AS THAT WILL ULTIMATELY SPELL THE DIFFERENCE BETWEEN LEGITIMATE LIGHT MEASURABLE AMOUNTS SUCH AS DEPICTED BY THE NAM AND OTHER MODELS...OR ESSENTIALLY NOTHING WHATSOEVER AS ADVERTISED BY THE 12Z GEM MODEL. THE PRESENCE OF PRECIP OR LACK THEREOF WILL ALSO AFFECT HIGHS WED...AND WITH CONFIDENCE BEING LOW OPTED TO MAKE LITTLE CHANGE TO PREVIOUS WITH GENERALLY MID-UPPER 30S. THURSDAY DAYTIME THROUGH FRIDAY NIGHT...THIS LOOKS TO FEATURE A BRIEF PERIOD OF SHORTWAVE RIDGING ALOFT BEFORE GIVING WAY TO THE NEXT POTENTIAL TROUGH MOVING IN FROM THE WEST-NORTHWEST. AS A RESULT...A BIT OF A TEMPERATURE ROLLER-COASTER STARTS TO DEVELOP. WITH INCREASING SOUTHERLY FLOW/GOOD WARM AIR ADVECTION GOING AHEAD OF THIS DISTURBANCE ON THURS...THIS SHOULD BE THE WARMEST DAY IN AWHILE...AND MADE LITTLE CHANGE TO HIGHS WITH A RANGE FROM UPPER 40S-UPPER 50S. THEN FROM FRIDAY INTO FRIDAY NIGHT...A POTENTIALLY FAIRLY STRONG COLD FRONT IS SLATED TO DROP THROUGH THE AREA...AND AS A RESULT FRIDAY HIGHS WERE LOWERED 3-5 DEGREES...BUT STILL UPPER 30S NORTH TO UPPER 40S SOUTH FOR NOW. AS EARLIER MENTIONED...SLIGHT POPS MAINLY FOR FRIDAY NIGHT ACCOMPANY THE PASSAGE OF THIS SHORTWAVE TROUGH...WHICH COULD BRING A QUICK SHOT OF LIGHT SNOW PER THE LATEST ECMWF BUT LESS-SO THE GFS. SATURDAY THROUGH SUNDAY...CONFIDENCE IS REASONABLY HIGH IN A RETURN TO DRY CONDITIONS FOR THE WEEKEND ASSUMING THAT FRIDAY NIGHT PRECIP MOVES OUT BY SATURDAY DAYTIME...AS THE PATTERN ALOFT AGAIN TRANSITIONS TO RIDGING. MADE LITTLE CHANGE TO SATURDAY HIGHS WITH A RANGE OF 40S ACROSS THE AREA...BUT THE LATEST ECMWF IS COOLER THAN THIS. VERY PRELIMINARILY...SUNDAY IS LOOKING LIKE THE OUTRIGHT-WARMEST DAY OF THE ENTIRE FORECAST...AND FOR NOW HAVE WIDESPREAD 50S IN NEB ZONES AND LOW 60S IN KS. && .AVIATION...(FOR THE 00Z KGRI TAF THROUGH 00Z MONDAY EVENING) ISSUED AT 544 PM CST SUN MAR 2 2014 THE NORTH NORTHEAST BREEZE SHOULD QUICKLY DIMINISH WITHIN THE FIRST COUPLE OF HOURS AS A STRONG SURFACE HIGH BUILDS IN. WIND WILL TURN LIGHT AND SOUTHEAST BY MORNING...INCREASING MONDAY MORNING AS LAPSE RATES INCREASE. ONLY SOME MID TO HIGH LEVEL CLOUDS ARE EXPECTED. && .CLIMATE... ISSUED AT 1146 AM CST SUN MAR 2 2014 IT IS EXTREMELY DIFFICULT TO GET HIGH TEMPS IN THE SINGLE DIGITS IN MARCH. IT HAS ONLY HAPPENED 5 TIMES EVER AT GRAND ISLAND AND HASTINGS. VULNERABLE LOW TEMP RECORDS TODAY: GRAND ISLAND: -5 IN 1960 (TIED) HASTINGS: -5 IN 1913 (TIED) * BOTH OF THESE RECORDS CAN BE BROKEN IF TEMPS DROP BELOW -5F BEFORE MIDNIGHT. VULNERABLE COLDEST DAILY HIGH TEMP RECORDS TODAY: GRAND ISLAND: 10 IN 2002 (CURRENT FORECAST HIGH: 7) HASTINGS: 11 IN 2002 (CURRENT FORECAST HIGH: 7) VULNERABLE LOW TEMP RECORDS FOR TOMORROW 3/3: GRAND ISLAND: -16 IN 1960 HASTINGS: -10 IN 1960 ALL-TIME COLDEST HIGH TEMPS FOR THE ENTIRE MONTH OF MARCH: GRAND ISLAND: 4 ON 3/10/1948 HASTINGS: 3 ON 3/11/1948 && .GID WATCHES/WARNINGS/ADVISORIES... NE...WIND CHILL WARNING FROM 9 PM THIS EVENING TO 10 AM CST MONDAY FOR NEZ039>041-046>049-061>064-073>076. WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 10 AM CST MONDAY FOR NEZ060-072-077-082>087. KS...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 10 AM CST MONDAY FOR KSZ005>007-017>019. && $$ SHORT TERM...HALBLAUB LONG TERM...PFANNKUCH AVIATION...HEINLEIN CLIMATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1210 PM CST SAT MAR 1 2014 .UPDATE... ISSUED AT 1210 PM CST SAT MAR 1 2014 ...WINTER WX ADVISORY CANCELLED... NO SUBSTANTIAL CHANGES NEEDED FOR THE NEXT 3- 6 HRS. HOWEVER... THE ADVISORY WAS CANCELLED AS WEBCAMS SHOW NO MORE THAN A GLORIFIED DUSTING OVER THE ADVISORY AREA. PERIODS OF -SN WILL CONTINUE AND WE ARE NOTING A HEALTHY BAND OVER THE SANDHILLS WHICH WAS NAILED BY THE HI-RES NAM-ARW ON YESTERDAY`S SHIFT. THIS BAND WILL PROBABLY CROSS THE FCST AREA N OF I-80...WITH BRIEF BUT DRASTIC REDUCTION IN VISIBILITY POSSIBLE. WE ARE NOTING THEDFORD DOWN TO 1/4SM AT 18Z. NONETHELESS...THE PROGRESSIVE NATURE OF THIS BAND WILL LIMIT ACCUMS. IF THIS BAND MAINTAINS ITS STRENGTH WE WILL HANDLE IT WITH AN SPS /SPECIAL WX STATEMENT/. WIND CHILL WATCH REMAINS AS POSTED FROM 4 AM. UPDATE ISSUED AT 959 AM CST SAT MAR 1 2014 RADAR AND SURFACE OBS SHOW BLOSSOMING LIGHT SNOW /-SN/ PRIMARILY WITHIN THE LOW-LEVEL DECK OF STRATUS THAT RESIDES WITHIN THE DENDRITIC GROWTH ZONE /DGZ/. EVEN THOUGH I AM NOT CONFIDENT ALL AREAS WILL MELT .01" LIQUID EQUIVALENT...POPS WERE INCREASED TO 80% THRU 20Z FOR THE ENTIRE FCST AREA. THIS WAS DONE TO TO FORCE THE FCST TO BEST DEPICT WHAT WILL PROBABLY CONT THRU THE AFTERNOON. THERE IS NO WAY WE CAN PINPOINT WHERE AND WHEN IT WILL SNOW. SO FCST WILL NOW READ AS PERIODS OF -SN. AM NOT EXPECTING MUCH MORE THAN A GOOD DUSTING HERE AND THERE TO THE S OF I-80. N OF I-80 THE SAME APPLIES BUT WITH A SOMEWHAT BETTER CHANCE FOR MODEST ACCUM. IT WILL BE INTERESTING TO SEE WHAT UNFOLDS THIS AFTERNOON. MODEL GUIDANCE IS ALL OVER THE PLACE...RESULTING IN ABOVE NORMAL UNCERTAINTY. SOME GUIDANCE INDICATES WE COULD SEE A REDEVELOPMENT OF MORE ROBUST SNOWFALL FOR A TIME...MAINLY OVER PARTS OF S-CNTRL NEB. UPDATE ISSUED AT 742 AM CST SAT MAR 1 2014 SENT AN EARLY ENHANCED SHORT-TERM FCST /ESTF/ UPDATE AS OUR HOURLY FCST TEMPS WERE RUNNING A LITTLE COLDER THAN REALITY. WE WILL STILL SEE A SLOW DOWNWARD SLIDE TODAY...BUT CURRENT TEMPS WERE MERGED WITH THE 11Z HRRR THRU MIDDAY. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 336 AM CST SAT MAR 1 2014 THE FOCUS DURING THE SHORT TERM PERIODS IS ON DEVELOPING SNOW...SNOW AMOUNTS...BITTER COLD TEMPS/WIND CHILLS AND ASSOCIATED WINTER HEADLINES. AN ARCTIC AIRMASS HAD SETTLED ACROSS THE PLAINS STATES WITH EARLY MORNING TEMPS AVERAGING IN THE SINGLE DIGITS AND TEENS. SNOW HAS BEEN DEVELOPING/FALLING ACROSS NW/NORTHERN NEB THROUGH MUCH OF THE PRE DAWN HOURS WITH VSBYS AS LOW AS 3/4SM AT TIMES. THE SNOW IS IN ASSOCIATION WITH ISENTROPIC LIFT AHEAD OF AN APPROACHING WAVE MOVING OUT OF THE CENTRAL ROCKIES...AND IN FAVORABLE UPPER JET DYNAMICS. THE SNOW WILL DEVELOP IN BANDS WITH THE GREATEST ACCUMULATIONS TODAY OCCURRING ACROSS NORTHERN NEBRASKA WITH OUR NORTHERN CWA ON THE PERIPHERY OF THE HIGHEST ACCUMULATIONS. SHORT TERM MODELS INDICATE THAT A DECENT SNOW BAND SHOULD ESTABLISH ACROSS VALLEY AND GREELEY COUNTIES AND SNOW AMOUNTS WILL BE DEPENDENT UPON WHERE THE BANDS SET UP. HAVE WENT WITH SNOWFALL ACCUMULATIONS OF 2 TO 4 INCHES WHERE OUR CURRENT WINTER WEATHER ADVISORY IS IN EFFECT...GENERALLY ALONG AND NORTH OF A LINE FROM LOUP CITY TO OSCEOLA NEB. FARTHER SOUTH...AREAS OF LIGHTER SNOW SHOULD DEVELOP/SPREAD EASTWARD BY MID DAY. HEADING INTO THE EVENING...THE SNOW SHOULD BEGIN TO TAPER OFF IN OUR NW ZONES FIRST AS A 1042MB SFC RIDGE BUILDS SOUTH FM THE DAKOTAS. NEXT ISSUE IS WHERE A SECOND ROUND/BAND OF SNOW WILL SET UP ACROSS KANSAS SATURDAY NIGHT INTO SUNDAY AS NEXT SYSTEM CROSSES THE SOUTHERN/CENTRAL PLAINS. THE 00Z MODELS KEPT THE BRUNT OF THIS NEXT SYSTEM TO OUR SOUTH WHERE THE POTENTIAL EXISTS FOR A SWATH OF HEAVY SNOWFALL IN GOOD DYNAMICS/ISENTROPIC LIFT/JET/FRONTOGENESIS WITH THIS STRONGER WAVE. OF CONCERN IS THAT THE 06Z NAM IS TRENDING FARTHER NORTH WITH THE BAND AND CLIPS OUR SE KS COUNTIES IN A BAND OF POTENTIAL HEAVY SNOW. DO NOT WANT TO JUMP ON ONE MODEL RUN AS TRENDS HAVE BEEN FARTHER SOUTH WITH THE BAND...AND SREF SNOW PLUMES DO NOT SUPPORT SNOWFALL AS HIGH AS LATEST NAM INDICATES IN THIS AREA. FOR SOME LOCATIONS IT COULD BE AN ALL OR NOTHING TYPE OF EVENT BUT DID INCLUDED THE POTENTIAL FOR A COUPLE TO SEVERAL INCHES ACROSS PORTIONS OF NC KANSAS AND WILL NEED TO CLOSELY MONITOR HOW THIS SYSTEM EVOLVES AS IT MOVES INLAND TODAY. FOR HEADLINES...AGAIN THE CURRENT WINTER WX ADVISORY WILL COVER THE SNOWFALL ACROSS OUR NORTHERN COUNTIES TODAY. CURRENT SNOWFALL FORECAST ACROSS THE REMAINDER OF OUR CWA DOES NOT SUPPORT A WINTER WX ADVISORY YET...AND ENOUGH UNCERTAINTY REMAINS IN KS TONIGHT TO HOLD OFF ON SNOW HEADLINE IN THIS AREA. NEXT CONCERN IS THE FRIGID WIND CHILLS EXPECTED THE COUPLE OF NIGHTS...AND WIND CHILLS FOR TONIGHT/SATURDAY NIGHT ARE EXPECTED TO DROP TO 25 TO 35 BELOW ZERO IN OUR NORTHERN ZONES. RATHER THAN ISSUE A WIND CHILL WARNING FOR TONIGHT IN THE SAME AREA THAT HAS THE WINTER WEATHER ADVISORY FOR TODAY...WILL GO WITH A WIND CHILL WATCH FOR TONIGHT AND LOCATIONS FARTHER SOUTH CAN BE INCLUDED IN A WIND CHILL ADVISORY IF THE GREATER SNOW REMAINS SOUTH...OR A WINTER WEATHER ADVISORY IF SNOW AMOUNTS LOOK HIGHER THAN CURRENT FORECAST. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 336 AM CST SAT MAR 1 2014 ON THE LARGE SCALE...ZONAL TO NORTHWEST FLOW REGIME WILL BE THE RULE THROUGH THE PERIOD. THERE WILL BE A FEW SHORT WAVES MOVING THROUGH THE FLOW...WITH THE MOST ORGANIZED WAVE FORECAST OVER THE AREA ON WEDNESDAY. SPECIFICALLY...EXPECT DRY WEATHER SUNDAY NIGHT THROUGH TUESDAY NIGHT WITH A GRADUAL WARMING TREND. WEDNESDAY LEFT A LOW CHANCE OF PRECIP...SNOW NORTHEAST AND RAIN SOUTHWEST. LOOKS LIKE THERE WILL BE ENOUGH LIFT BUT MOISTURE WILL BE LIMITED AS THE SYSTEM DEVELOPS OVER THE AREA. THE SYSTEM IS FORECAST TO DEEPEN AS IT MOVES EAST OF THE AREA AND THIS CYCLOGENESIS WILL FORCE INCREASED MOISTURE ADVECTION. SO RIGHT NOW IT APPEARS PRECIP AMOUNTS WILL BE ON THE LOW END. WE WILL HAVE TO CONTINUE TO MONITOR... THURSDAY AND FRIDAY APPEAR TO BE DRY...AS THE NEXT SHORT WAVE AND APPROACHES FROM THE NORTHWEST. AS MENTIONED...WE EXPECT A GRADUAL WARMING TREND MONDAY THROUGH FRIDAY AS THE ARCTIC AIR MASS CURRENTLY ON TOP OF US IS GRADUALLY MODIFIED AND PUSHED EAST. A SOUTHERLY FLOW WILL MIX IN WARMER TEMPS MONDAY AND TUESDAY. THE POTENTIAL DEVELOPING LOW PRESSURE AREA WILL NOT BRING A SIGNIFICANT TEMPERATURE CHANGE BEHIND IT...AS A MATTER OF FACT...IT IS FORECAST TO MOVE OFF FAST ENOUGH THAT WINDS WILL QUICKLY REBOUND TO THE SOUTH ON THURSDAY AND FRIDAY AND BRING NEAR NORMAL TEMPS TO THE AREA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1210 PM CST SAT MAR 1 2014 THIS AFTERNOON: VFR IN PERIODS OF -SN EXCEPT TEMPO MVFR CIGS/VSBYS IN HEALTHIER SNOW BANDS. THEY WILL BE TRANSIENT. NE WINDS MAY OCCASIONALLY GUST TO 20 KTS...BUT OVERALL GUSTINESS IS DONE. CONFIDENCE: MEDIUM TONIGHT: VFR STRATUS CIGS AROUND 5K FT. NNE WINDS AROUND 10 KTS. CONFIDENCE: MEDIUM SUN: VFR STRATUS CIGS AROUND 5K FT...BUT COULD BECOME SCT REVEALING HIGH CLOUDS. NNE WINDS 5-10 KTS. CONFIDENCE: MEDIUM && .CLIMATE... ISSUED AT 1210 PM CST SAT MAR 1 2014 FOLLOWING BELOW IS A RECAP OF THE DAILY RECORD COLDEST HIGH TEMPS FOR GRAND ISLAND AND HASTINGS THAT WILL BE IN JEOPARDY SUNDAY. ITS NOT OUT OF THE REALM OF POSSIBILITY THAT SUNDAY COULD COME VERY CLOSE TO THE COLDEST MAXIMUM (HIGH) TEMPERATURE ON RECORD FOR ANY DAY IN MARCH: THE DAILY RECORDS FOR COLDEST HIGH TEMP STAND AS FOLLOWS: MARCH 2: GRAND ISLAND...10 IN 2002 HASTINGS...11 IN 2002 MARCH 3: GRAND ISLAND...8 IN 1916 HASTINGS...10 IN 2002 ALL-TIME COLDEST HIGH TEMP ON RECORD FOR ANY DAY IN MARCH: GRAND ISLAND: 4 DEGREES ON 3-10-1948 HASTINGS: 3 DEGREES ON 3-11-1948 && .GID WATCHES/WARNINGS/ADVISORIES... NE...WIND CHILL WATCH FROM 10 PM CST THIS EVENING THROUGH SUNDAY MORNING FOR NEZ039>041-046>049. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...FAY LONG TERM...EDDY AVIATION...HALBLAUB CLIMATE...PFANNKUCH/HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1000 AM CST SAT MAR 1 2014 .UPDATE... ISSUED AT 959 AM CST SAT MAR 1 2014 RADAR AND SURFACE OBS SHOW BLOSSOMING LIGHT SNOW /-SN/ PRIMARILY WITHIN THE LOW-LEVEL DECK OF STRATUS THAT RESIDES WITHIN THE DENDRITIC GROWTH ZONE /DGZ/. EVEN THOUGH I AM NOT CONFIDENT ALL AREAS WILL MELT .01" LIQUID EQUIVALENT...POPS WERE INCREASED TO 80% THRU 20Z FOR THE ENTIRE FCST AREA. THIS WAS DONE TO TO FORCE THE FCST TO BEST DEPICT WHAT WILL PROBABLY CONT THRU THE AFTERNOON. THERE IS NO WAY WE CAN PINPOINT WHERE AND WHEN IT WILL SNOW. SO FCST WILL NOW READ AS PERIODS OF -SN. AM NOT EXPECTING MUCH MORE THAN A GOOD DUSTING HERE AND THERE TO THE S OF I-80. N OF I-80 THE SAME APPLIES BUT WITH A SOMEWHAT BETTER CHANCE FOR MODEST ACCUM. IT WILL BE INTERESTING TO SEE WHAT UNFOLDS THIS AFTERNOON. MODEL GUIDANCE IS ALL OVER THE PLACE...RESULTING IN ABOVE NORMAL UNCERTAINTY. SOME GUIDANCE INDICATES WE COULD SEE A REDEVELOPMENT OF MORE ROBUST SNOWFALL FOR A TIME...MAINLY OVER PARTS OF S-CNTRL NEB. UPDATE ISSUED AT 742 AM CST SAT MAR 1 2014 SENT AN EARLY ENHANCED SHORT-TERM FCST /ESTF/ UPDATE AS OUR HOURLY FCST TEMPS WERE RUNNING A LITTLE COLDER THAN REALITY. WE WILL STILL SEE A SLOW DOWNWARD SLIDE TODAY...BUT CURRENT TEMPS WERE MERGED WITH THE 11Z HRRR THRU MIDDAY. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 336 AM CST SAT MAR 1 2014 THE FOCUS DURING THE SHORT TERM PERIODS IS ON DEVELOPING SNOW...SNOW AMOUNTS...BITTER COLD TEMPS/WIND CHILLS AND ASSOCIATED WINTER HEADLINES. AN ARCTIC AIRMASS HAD SETTLED ACROSS THE PLAINS STATES WITH EARLY MORNING TEMPS AVERAGING IN THE SINGLE DIGITS AND TEENS. SNOW HAS BEEN DEVELOPING/FALLING ACROSS NW/NORTHERN NEB THROUGH MUCH OF THE PRE DAWN HOURS WITH VSBYS AS LOW AS 3/4SM AT TIMES. THE SNOW IS IN ASSOCIATION WITH ISENTROPIC LIFT AHEAD OF AN APPROACHING WAVE MOVING OUT OF THE CENTRAL ROCKIES...AND IN FAVORABLE UPPER JET DYNAMICS. THE SNOW WILL DEVELOP IN BANDS WITH THE GREATEST ACCUMULATIONS TODAY OCCURRING ACROSS NORTHERN NEBRASKA WITH OUR NORTHERN CWA ON THE PERIPHERY OF THE HIGHEST ACCUMULATIONS. SHORT TERM MODELS INDICATE THAT A DECENT SNOW BAND SHOULD ESTABLISH ACROSS VALLEY AND GREELEY COUNTIES AND SNOW AMOUNTS WILL BE DEPENDENT UPON WHERE THE BANDS SET UP. HAVE WENT WITH SNOWFALL ACCUMULATIONS OF 2 TO 4 INCHES WHERE OUR CURRENT WINTER WEATHER ADVISORY IS IN EFFECT...GENERALLY ALONG AND NORTH OF A LINE FROM LOUP CITY TO OSCEOLA NEB. FARTHER SOUTH...AREAS OF LIGHTER SNOW SHOULD DEVELOP/SPREAD EASTWARD BY MID DAY. HEADING INTO THE EVENING...THE SNOW SHOULD BEGIN TO TAPER OFF IN OUR NW ZONES FIRST AS A 1042MB SFC RIDGE BUILDS SOUTH FM THE DAKOTAS. NEXT ISSUE IS WHERE A SECOND ROUND/BAND OF SNOW WILL SET UP ACROSS KANSAS SATURDAY NIGHT INTO SUNDAY AS NEXT SYSTEM CROSSES THE SOUTHERN/CENTRAL PLAINS. THE 00Z MODELS KEPT THE BRUNT OF THIS NEXT SYSTEM TO OUR SOUTH WHERE THE POTENTIAL EXISTS FOR A SWATH OF HEAVY SNOWFALL IN GOOD DYNAMICS/ISENTROPIC LIFT/JET/FRONTOGENESIS WITH THIS STRONGER WAVE. OF CONCERN IS THAT THE 06Z NAM IS TRENDING FARTHER NORTH WITH THE BAND AND CLIPS OUR SE KS COUNTIES IN A BAND OF POTENTIAL HEAVY SNOW. DO NOT WANT TO JUMP ON ONE MODEL RUN AS TRENDS HAVE BEEN FARTHER SOUTH WITH THE BAND...AND SREF SNOW PLUMES DO NOT SUPPORT SNOWFALL AS HIGH AS LATEST NAM INDICATES IN THIS AREA. FOR SOME LOCATIONS IT COULD BE AN ALL OR NOTHING TYPE OF EVENT BUT DID INCLUDED THE POTENTIAL FOR A COUPLE TO SEVERAL INCHES ACROSS PORTIONS OF NC KANSAS AND WILL NEED TO CLOSELY MONITOR HOW THIS SYSTEM EVOLVES AS IT MOVES INLAND TODAY. FOR HEADLINES...AGAIN THE CURRENT WINTER WX ADVISORY WILL COVER THE SNOWFALL ACROSS OUR NORTHERN COUNTIES TODAY. CURRENT SNOWFALL FORECAST ACROSS THE REMAINDER OF OUR CWA DOES NOT SUPPORT A WINTER WX ADVISORY YET...AND ENOUGH UNCERTAINTY REMAINS IN KS TONIGHT TO HOLD OFF ON SNOW HEADLINE IN THIS AREA. NEXT CONCERN IS THE FRIGID WIND CHILLS EXPECTED THE COUPLE OF NIGHTS...AND WIND CHILLS FOR TONIGHT/SATURDAY NIGHT ARE EXPECTED TO DROP TO 25 TO 35 BELOW ZERO IN OUR NORTHERN ZONES. RATHER THAN ISSUE A WIND CHILL WARNING FOR TONIGHT IN THE SAME AREA THAT HAS THE WINTER WEATHER ADVISORY FOR TODAY...WILL GO WITH A WIND CHILL WATCH FOR TONIGHT AND LOCATIONS FARTHER SOUTH CAN BE INCLUDED IN A WIND CHILL ADVISORY IF THE GREATER SNOW REMAINS SOUTH...OR A WINTER WEATHER ADVISORY IF SNOW AMOUNTS LOOK HIGHER THAN CURRENT FORECAST. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 336 AM CST SAT MAR 1 2014 ON THE LARGE SCALE...ZONAL TO NORTHWEST FLOW REGIME WILL BE THE RULE THROUGH THE PERIOD. THERE WILL BE A FEW SHORT WAVES MOVING THROUGH THE FLOW...WITH THE MOST ORGANIZED WAVE FORECAST OVER THE AREA ON WEDNESDAY. SPECIFICALLY...EXPECT DRY WEATHER SUNDAY NIGHT THROUGH TUESDAY NIGHT WITH A GRADUAL WARMING TREND. WEDNESDAY LEFT A LOW CHANCE OF PRECIP...SNOW NORTHEAST AND RAIN SOUTHWEST. LOOKS LIKE THERE WILL BE ENOUGH LIFT BUT MOISTURE WILL BE LIMITED AS THE SYSTEM DEVELOPS OVER THE AREA. THE SYSTEM IS FORECAST TO DEEPEN AS IT MOVES EAST OF THE AREA AND THIS CYCLOGENESIS WILL FORCE INCREASED MOISTURE ADVECTION. SO RIGHT NOW IT APPEARS PRECIP AMOUNTS WILL BE ON THE LOW END. WE WILL HAVE TO CONTINUE TO MONITOR... THURSDAY AND FRIDAY APPEAR TO BE DRY...AS THE NEXT SHORT WAVE AND APPROACHES FROM THE NORTHWEST. AS MENTIONED...WE EXPECT A GRADUAL WARMING TREND MONDAY THROUGH FRIDAY AS THE ARCTIC AIR MASS CURRENTLY ON TOP OF US IS GRADUALLY MODIFIED AND PUSHED EAST. A SOUTHERLY FLOW WILL MIX IN WARMER TEMPS MONDAY AND TUESDAY. THE POTENTIAL DEVELOPING LOW PRESSURE AREA WILL NOT BRING A SIGNIFICANT TEMPERATURE CHANGE BEHIND IT...AS A MATTER OF FACT...IT IS FORECAST TO MOVE OFF FAST ENOUGH THAT WINDS WILL QUICKLY REBOUND TO THE SOUTH ON THURSDAY AND FRIDAY AND BRING NEAR NORMAL TEMPS TO THE AREA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 519 AM CST SAT MAR 1 2014 TIMING OF SNOW AND LOWERING CIGS/VSBYS REMAINS THE MAIN CHALLENGE FOR KGRI. SNOW HAS BEEN FALLING ACROSS NORTHERN/NORTHWEST NEBRASKA ALL NIGHT AND SHORT TERM FORECAST MODELS SUGGEST THE SNOW WILL REACH KGRI AROUND MID DAY. KGRI WILL BE ON THE PERIPHERY OF HEAVIER SNOWFALL TO THE NORTH AND SNOW SHOULD BE INTERMITTENT DEPENDING ON WHERE SNOW BANDS SET UP. AT THE ONSET OF THE PCPN HAVE LOWERED CIGS/VSBYS TO MVFR...WITH IMPROVING CONDITIONS/DRYING OUT TONIGHT AS SNOW BAND SHIFTS FARTHER SOUTH. && .CLIMATE... ISSUED AT 359 PM CST FRI FEB 28 2014 FOLLOWING BELOW IS A RECAP OF THE DAILY RECORD COLDEST HIGH TEMPERATURES FOR GRAND ISLAND AND HASTINGS THAT WILL BE IN JEOPARDY SUNDAY. ITS NOT OUT OF THE REALM OF POSSIBILITY THAT SUNDAY COULD COME VERY CLOSE TO THE COLDEST MAXIMUM (HIGH) TEMPERATURE ON RECORD FOR ANY DAY IN MARCH: THE DAILY RECORDS FOR COLDEST MAX TEMP STAND AS FOLLOWS: - MARCH 2: GRAND ISLAND...10 IN 2002 HASTINGS...11 IN 2002 - MARCH 3: GRAND ISLAND...8 IN 1916 HASTINGS...10 IN 2002 THE COLDEST MAX TEMP ON RECORD FOR ANY DAY IN MARCH: - GRAND ISLAND: 4 DEGREES ON 3-10-1948 - HASTINGS: 3 DEGREES ON 3-11-1948 && .GID WATCHES/WARNINGS/ADVISORIES... NE...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ039>041-046>049. WIND CHILL WATCH FROM THIS EVENING THROUGH SUNDAY MORNING FOR NEZ039>041-046>049. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...FAY LONG TERM...EDDY AVIATION...FAY CLIMATE...PFANNKUCH/HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
742 AM CST SAT MAR 1 2014 .UPDATE... ISSUED AT 742 AM CST SAT MAR 1 2014 SENT AN EARLY ENHANCED SHORT-TERM FCST /ESTF/ UPDATE AS OUR HOURLY FCST TEMPS WERE RUNNING A LITTLE COLDER THAN REALITY. WE WILL STILL SEE A SLOW DOWNWARD SLIDE TODAY...BUT CURRENT TEMPS WERE MERGED WITH THE 11Z HRRR THRU MIDDAY. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 336 AM CST SAT MAR 1 2014 THE FOCUS DURING THE SHORT TERM PERIODS IS ON DEVELOPING SNOW...SNOW AMOUNTS...BITTER COLD TEMPS/WIND CHILLS AND ASSOCIATED WINTER HEADLINES. AN ARCTIC AIRMASS HAD SETTLED ACROSS THE PLAINS STATES WITH EARLY MORNING TEMPS AVERAGING IN THE SINGLE DIGITS AND TEENS. SNOW HAS BEEN DEVELOPING/FALLING ACROSS NW/NORTHERN NEB THROUGH MUCH OF THE PRE DAWN HOURS WITH VSBYS AS LOW AS 3/4SM AT TIMES. THE SNOW IS IN ASSOCIATION WITH ISENTROPIC LIFT AHEAD OF AN APPROACHING WAVE MOVING OUT OF THE CENTRAL ROCKIES...AND IN FAVORABLE UPPER JET DYNAMICS. THE SNOW WILL DEVELOP IN BANDS WITH THE GREATEST ACCUMULATIONS TODAY OCCURRING ACROSS NORTHERN NEBRASKA WITH OUR NORTHERN CWA ON THE PERIPHERY OF THE HIGHEST ACCUMULATIONS. SHORT TERM MODELS INDICATE THAT A DECENT SNOW BAND SHOULD ESTABLISH ACROSS VALLEY AND GREELEY COUNTIES AND SNOW AMOUNTS WILL BE DEPENDENT UPON WHERE THE BANDS SET UP. HAVE WENT WITH SNOWFALL ACCUMULATIONS OF 2 TO 4 INCHES WHERE OUR CURRENT WINTER WEATHER ADVISORY IS IN EFFECT...GENERALLY ALONG AND NORTH OF A LINE FROM LOUP CITY TO OSCEOLA NEB. FARTHER SOUTH...AREAS OF LIGHTER SNOW SHOULD DEVELOP/SPREAD EASTWARD BY MID DAY. HEADING INTO THE EVENING...THE SNOW SHOULD BEGIN TO TAPER OFF IN OUR NW ZONES FIRST AS A 1042MB SFC RIDGE BUILDS SOUTH FM THE DAKOTAS. NEXT ISSUE IS WHERE A SECOND ROUND/BAND OF SNOW WILL SET UP ACROSS KANSAS SATURDAY NIGHT INTO SUNDAY AS NEXT SYSTEM CROSSES THE SOUTHERN/CENTRAL PLAINS. THE 00Z MODELS KEPT THE BRUNT OF THIS NEXT SYSTEM TO OUR SOUTH WHERE THE POTENTIAL EXISTS FOR A SWATH OF HEAVY SNOWFALL IN GOOD DYNAMICS/ISENTROPIC LIFT/JET/FRONTOGENESIS WITH THIS STRONGER WAVE. OF CONCERN IS THAT THE 06Z NAM IS TRENDING FARTHER NORTH WITH THE BAND AND CLIPS OUR SE KS COUNTIES IN A BAND OF POTENTIAL HEAVY SNOW. DO NOT WANT TO JUMP ON ONE MODEL RUN AS TRENDS HAVE BEEN FARTHER SOUTH WITH THE BAND...AND SREF SNOW PLUMES DO NOT SUPPORT SNOWFALL AS HIGH AS LATEST NAM INDICATES IN THIS AREA. FOR SOME LOCATIONS IT COULD BE AN ALL OR NOTHING TYPE OF EVENT BUT DID INCLUDED THE POTENTIAL FOR A COUPLE TO SEVERAL INCHES ACROSS PORTIONS OF NC KANSAS AND WILL NEED TO CLOSELY MONITOR HOW THIS SYSTEM EVOLVES AS IT MOVES INLAND TODAY. FOR HEADLINES...AGAIN THE CURRENT WINTER WX ADVISORY WILL COVER THE SNOWFALL ACROSS OUR NORTHERN COUNTIES TODAY. CURRENT SNOWFALL FORECAST ACROSS THE REMAINDER OF OUR CWA DOES NOT SUPPORT A WINTER WX ADVISORY YET...AND ENOUGH UNCERTAINTY REMAINS IN KS TONIGHT TO HOLD OFF ON SNOW HEADLINE IN THIS AREA. NEXT CONCERN IS THE FRIGID WIND CHILLS EXPECTED THE COUPLE OF NIGHTS...AND WIND CHILLS FOR TONIGHT/SATURDAY NGIHT ARE EXPECTED TO DROP TO 25 TO 35 BELOW ZERO IN OUR NORTHERN ZONES. RATHER THAN ISSUE A WIND CHILL WARNING FOR TONIGHT IN THE SAME AREA THAT HAS THE WINTER WEATHER ADVISORY FOR TODAY...WILL GO WITH A WIND CHILL WATCH FOR TONIGHT AND LOCATIONS FARTHER SOUTH CAN BE INCLUDED IN A WIND CHILL ADVISORY IF THE GREATER SNOW REMAINS SOUTH...OR A WINTER WEATHER ADVISORY IF SNOW AMOUNTS LOOK HIGHER THAN CURRENT FORECAST. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 336 AM CST SAT MAR 1 2014 ON THE LARGE SCALE...ZONAL TO NORTHWEST FLOW REGIME WILL BE THE RULE THROUGH THE PERIOD. THERE WILL BE A FEW SHORT WAVES MOVING THROUGH THE FLOW...WITH THE MOST ORGANIZED WAV FORECAST OVER THE AREA ON WEDNESDAY. SPECIFICALLY...EXPECT DRY WEATHER SUNDAY NIGHT THROUGH TUESDAY NIGHT WITH A GRADUAL WARMING TREND. WEDNESDAY LEFT A LOW CHANCE OF PRECIP...SNOW NORTHEAST AND RAIN SOUTHWEST. LOOKS LIKE THERE WILL BE ENOUGH LIFT BUT MOISTURE WILL BE LIMTED AS THE SYSTEM DEVELOPS OVER THE AREA. THE SYSTEM IS FORECAST TO DEEPEN AS IT MOVES EAST OF THE AREA AND THIS CYCLOGENISIS WILL FORCE INCREASED MOISTURE ADVECTION. SO RIGHT NOW IT APPEARS PRECIP AMOUNTS WILL BE ON THE LOW END. WE WILL HAVE TO CONTINUE TO MONITOR... THURSDAY AND FRIDAY APPEAR TO BE DRY...AS THE NEXT SHORT WAVE AND APPROCHES FROM THE NORTHWEST. AS MENTIONED...WE EXPECT A GRADUAL WARMING TREND MONDAY THROUGH FRIDAY AS THE ARCTIC AIR MASS CURRENTLY ON TOP OF US IS GRADUALLY MODIFIED AND PUSHED EAST. A SOUTHERLY FLOW WILL MIX IN WARMER TEMPS MONDAY AND TUESDAY. THE POTENTIAL DEVELOPING LOW PRESSURE AREA WILL NOT BRING A SIGNIFICANT TEMPERATURE CHANGE BEHIND IT...AS A MATTER OF FACT...IT IS FORECASTTOMOVE OFF FAST ENOUGH THAT WINDS WILL QUICKLY REBOUND TO THE SOUTH ON THURSDAY AND FRIDAY AND BRING NEAR NORMAL TEMPS TO THE AREA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 519 AM CST SAT MAR 1 2014 TIMING OF SNOW AND LOWERING CIGS/VSBYS REMAINS THE MAIN CHALLENGE FOR KGRI. SNOW HAS BEEN FALLING ACROSS NORTHERN/NORTHWEST NEBRASKA ALL NIGHT AND SHORT TERM FORECAST MODELS SUGGEST THE SNOW WILL REACH KGRI AROUND MID DAY. KGRI WILL BE ON THE PERIPHERY OF HEAVIER SNOWFALL TO THE NORTH AND SNOW SHOULD BE INTERMITTENT DEPENDING ON WHERE SNOW BANDS SET UP. AT THE ONSET OF THE PCPN HAVE LOWERED CIGS/VSBYS TO MVFR...WITH IMPROVING CONDITIONS/DRYING OUT TONIGHT AS SNOW BAND SHIFTS FARTHER SOUTH. && .CLIMATE... ISSUED AT 359 PM CST FRI FEB 28 2014 FOLLOWING BELOW IS A RECAP OF THE DAILY RECORD COLDEST HIGH TEMPERATURES FOR GRAND ISLAND AND HASTINGS THAT WILL BE IN JEOPARDY SUNDAY. ITS NOT OUT OF THE REALM OF POSSIBILITY THAT SUNDAY COULD COME VERY CLOSE TO THE COLDEST MAXIMUM (HIGH) TEMPERATURE ON RECORD FOR ANY DAY IN MARCH: THE DAILY RECORDS FOR COLDEST MAX TEMP STAND AS FOLLOWS: - MARCH 2: GRAND ISLAND...10 IN 2002 HASTINGS...11 IN 2002 - MARCH 3: GRAND ISLAND...8 IN 1916 HASTINGS...10 IN 2002 THE COLDEST MAX TEMP ON RECORD FOR ANY DAY IN MARCH: - GRAND ISLAND: 4 DEGREES ON 3-10-1948 - HASTINGS: 3 DEGREES ON 3-11-1948 && .GID WATCHES/WARNINGS/ADVISORIES... NE...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ039>041-046>049. WIND CHILL WATCH FROM THIS EVENING THROUGH SUNDAY MORNING FOR NEZ039>041-046>049. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...FAY LONG TERM...EDDY AVIATION...FAY CLIMATE...PFANNKUCH/HALBLAUB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1115 PM CST FRI FEB 28 2014 .UPDATE... ISSUED AT 748 PM CST FRI FEB 28 2014 FIRST BATCH OF PRECIPITATION WAS MOVING OUT OF THE FA WITH A LINGERING FREEZING RAIN/SNOW MIX THROUGH ABOUT 03Z FAR SERN COUNTIES...WITH A FEW TRAILING FLURRIES/SNOW SHOWERS AN HR OR SO LONGER. THIS WAS HANDLED WITH UPDATE A BIT AGO. OTHERWISE 18Z AND LATEST SHORT-TERM HRRR MODELS SUGGESTED THE ONSET OF THE NEXT ROUND OF SNOW WILL BE A BIT SLOWER. THUS PUSHED BACK START TIME OF WINTER WEATHER ADVISORY 3 TO 6 HRS. NO OTHER SIGNIFICANT CHANGES AT THIS TIME. && .SHORT TERM...(TONIGHT THROUGH MONDAY) ISSUED AT 305 PM CST FRI FEB 28 2014 WHAT A WAY TO START THE MONTH OF MARCH...SOME OF THE COLDEST AIR OF THE SEASON IS EXPECTED TO SETTLE OVER THE AREA THIS WEEKEND WITH THE POTENTIAL TO SMASH LOW TEMPERATURE RECORDS FOR THE DATES. THE COLD FRONT THAT WILL USHER IN THE ARCTIC AIR WAS MOVING INTO SOUTHEAST NEBRASKA AND SOUTHWEST IOWA AT 20Z WITH RADAR SHOWING A FRONTOGENETIC BAND OF LIGHT PRECIP OVER EAST CENTRAL NEBRASKA. EXPECT THE MAJORITY OF THIS PRECIP TO BE EAST OF THE MISSOURI RIVER AT THE START OF THE PERIOD AND SHOULD SEE A PERIOD OF LIGHT SNOW EARLY THIS EVENING IN PARTS OF SOUTHWEST IOWA AS THE COLD AIR DEEPENS IN THE LOW LEVELS BEFORE MOVING OFF TO THE EAST. A SECOND ROUND OF LIGHT SNOW IS EXPECTED TO DEVELOP TONIGHT NEAR THE NEBRASKA SOUTH DAKOTA BORDER AND SPREAD EAST INTO NORTHWEST PARTS OF THE FORECAST AREA AFTER MIDNIGHT. THE FRONTOGENETIC FORCING ASSOCIATED WITH THIS BAND OF SNOW PUSHES SOUTH ACROSS THE REST OF THE AREA DURING THE DAY ON SATURDAY AND INTO KANSAS AND NORTHERN MISSOURI SATURDAY NIGHT WHERE STRONGER FORCING IS INDICATED ALONG THE 850MB FRONT. EXPECT SNOW RATIOS TO BE RATHER HIGH WITH THIS EVENT DUE TO THE EXTREMELY COLD AIR SO SNOWFALL IN THE 4 TO 6 INCH RANGE IS POSSIBLE ACROSS EASTERN NEBRASKA AND SOUTHWEST IOWA WITH ISOLATED 6+ IN FAR SOUTHEAST NEBRASKA. THE MAJORITY OF SNOWFALL FOR THE FORECAST AREA IS EXPECTED DURING THE DAY ON SATURDAY WITH ADDITIONAL AMOUNTS IN THE SOUTH SATURDAY NIGHT. SNOW MAY LINGER OVER THE FAR SOUTH INTO SUNDAY WITH SOME LIGHT ACCUMULATION BEFORE ENDING SUNDAY AFTERNOON. WITH THE ADDITION OF FRESH SNOW COVER...RECORD COLD TEMPERATURES LOOK LIKELY WITH FORECAST HIGHS WELL BELOW CURRENT RECORD LOW MAXIMUMS AT ALL THREE CLIMATE STATIONS ON SATURDAY AND SUNDAY. RECORD LOW MINIMUMS ARE ALSO POSSIBLE AT SEVERAL SITES. WIND CHILL HEADLINES ARE LIKELY TO REPLACE WINTER WEATHER HEADLINES AFTER THEIR EXPIRATION SATURDAY NIGHT AND SUNDAY AS THE ARCTIC HIGH PRESSURE WORKS SOUTH INTO THE LOWER MISSOURI VALLEY SUNDAY NIGHT AND MONDAY. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 305 PM CST FRI FEB 28 2014 MONDAY NIGHT THROUGH NEXT FRIDAY...THIS FORECAST PERIOD IS CHARACTERIZED BY A WARMING TREND THROUGH THE WORK WEEK AND MEAGER PRECIPITATION CHANCES THROUGHOUT. MONDAY NIGHT WILL BE COLD...BUT NOT NEARLY AS COLD AS THE PREVIOUS NIGHT. TEMPERATURES REBOUND A BIT WITH LOWS STAYING ABOVE ZERO...NOWHERE NEAR RECORD TERRITORY. BY TUESDAY AFTERNOON WE BEGIN A GRADUAL WARM-UP AS 850MB TEMPERATURES FINALLY RISE ABOVE ZERO CELSIUS. THIS WARMING TREND CONTINUES THROUGH THE WORK WEEK WITH 850MB TEMPERATURES PUSHING 10 CELSIUS BY THURSDAY AND THURSDAY NIGHT. GIVEN THIS AMOUNT OF WARMTH...DAYTIME HIGHS WILL LIKELY EXCEED 50 DEGREES THURSDAY AND MAYBE EVEN FRIDAY DEPENDING ON THE TIMING OF THE WEEKEND SYSTEM. PRECIPITATION-WISE THE FORECAST IS GENERALLY DRY. A COUPLE DIFFERENT SHORTWAVES EMBEDDED IN THE MID-LEVEL NORTHWEST FLOW WILL TRANSLATE THROUGH THE FORECAST AREA. HOWEVER MEAGER MOISTURE PROFILES ONLY POINT TO A SLIGHT CHANCE OF PRECIPITATION ON WEDNESDAY...OTHERWISE WE ANTICIPATE DRY WEATHER THROUGH THURSDAY NIGHT AS UPPER LEVEL RIDGING DOMINATES. BY FRIDAY THE UPPER LEVEL RIDGE BREAKS DOWN AND THE NEXT WEATHER MAKER ENTERS THE PICTURE. AT THIS TIME MODEL GUIDANCES POINTS TO AN INCREASED POTENTIAL FOR PRECIPITATION...LIKELY A RAIN/SNOW MIX...BY FRIDAY NIGHT AND CONTINUING INTO THE WEEKEND. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1115 PM CST FRI FEB 28 2014 SNOW IS EXPECTED TO MOVE BACK INTO NERN NEBRASKA LATE TONIGHT AND THEN ACROSS KLNK/KOMA SITES BY LATE MORNING/EARLY AFTERNOON. A TEMPO GROUP WITH VSBYS BELOW 1SM WAS CARRIED AT EACH SITE DURING THE WINDOW WHEN BEST FORCING WAS EXPECTED TO PROVIDE LOWEST CONDITIONS. MAIN QUESTION WILL BE PREVAILING CIGS/VSBYS DURING MUCH OF THE EVENT. THERE IS SOME CHANCE PREVAILING CONDITIONS COULD BE A BIT BETTER THAN 06Z FORECAST INDICATED...BUT ALSO NEARLY EQUAL CHANCES THAT THE POOREST CONDITIONS COULD LAST LONGER AS WELL. && .CLIMATE... ISSUED AT 305 PM FRI FEB 28 2014 COLD MAX TEMP AND RECORD MIN TEMP RECORDS FOR THE FIRST FEW DAYS IN MARCH. ASTERISK VALUES INDICATE POTENTIAL BROKEN RECORDS BASED ON CURRENT FORECAST. 3/1 3/2 3/3 OMAHA 12*/-9 13*/-4* 10*/-5* LINCOLN 16*/-6 14*/-7 10/-10 NORFOLK 11*/-11 10*/-15* 6/-10* && .OAX WATCHES/WARNINGS/ADVISORIES... NE...WINTER WEATHER ADVISORY FROM 9 AM SATURDAY TO 6 AM CST SUNDAY FOR NEZ034-043>045-050>053-065>067-078. WINTER WEATHER ADVISORY FROM NOON SATURDAY TO NOON CST SUNDAY FOR NEZ068-088>093. WINTER WEATHER ADVISORY FROM 3 AM SATURDAY TO MIDNIGHT CST SATURDAY NIGHT FOR NEZ011-012-015>018-030>033-042. IA...WINTER WEATHER ADVISORY FROM 9 AM SATURDAY TO 6 AM CST SUNDAY FOR IAZ043-055-056-069-079-080. WINTER WEATHER ADVISORY FROM NOON SATURDAY TO NOON CST SUNDAY FOR IAZ090-091. && $$ UPDATE...CHERMOK SHORT TERM...FOBERT LONG TERM...PEARSON AVIATION...CHERMOK CLIMATE...FOBERT
AREA FORECAST DISCUSSION...CORRECTED
NWS ALBUQUERQUE NM
328 PM MST SAT MAR 1 2014 .SYNOPSIS... WIDESPREAD RAIN AND HIGH ELEVATION SNOW TODAY WILL GRADUALLY CHANGE OVER TO SNOW DOWN TO NEAR 6000 FEET TONIGHT BEFORE MIXING WITH RAIN AGAIN SUNDAY. SIGNIFICANT ACCUMULATIONS WILL OCCUR IN THE HIGHER TERRAIN OF THE NORTHERN AND WESTERN MOUNTAINS. STRONG WINDS OVER MUCH OF EASTERN NEW MEXICO WILL TAPER OFF THROUGH THE EVENING. A POTENT COLD FRONT OVER THE NORTHEAST PLAINS WILL ALLOW RAIN TO CHANGE OVER TO A MIX OF SNOW...SLEET...AND FREEZING RAIN THROUGH SUNDAY. THIS STORM SYSTEM WILL MOVE OUT OF THE AREA SUNDAY... LEAVING BEHIND COOLER TEMPERATURES THROUGH MONDAY. THE REMAINDER OF THE WEEK WILL BE NEAR NORMAL FOR EARLY MARCH AS A COUPLE WEAK DISTURBANCES MOVE OVER THE STATE. PERIODIC BREEZY CONDITIONS WILL IMPACT THE PLAINS AND PATCHY CLOUD COVER WITH EVEN A FEW SHOWERS WILL AFFECT THE HIGH TERRAIN. && .DISCUSSION... WHAT A WELCOME SITE IT IS AS A DEEP FETCH OF RAIN AND HIGH TERRAIN SNOW IMPACTS CENTRAL AND WESTERN NM. THE WATER VAPOR LOOP STILL SHOWS THE CORE OF A WELL-DEFINED STORM SYSTEM CRASHING ONSHORE SOUTHERN CALIFORNIA WITH A MASSIVE FETCH OF MOIST SW FLOW SHIFTING INTO AZ AND NM. CIRA TOTAL PWAT VALUES ARE ABOVE 200PCT OF NORMAL IN THIS PLUME AND IT WILL SHIFT DIRECTLY OVER NM THRU THIS EVENING. SFC AND MID LEVEL TEMPS ARE TRENDING DOWN WITH THE AID OF EVAPORATIONAL COOLING AND SOME WEAK COLD AIR ADVECTION. SNOW REPORTS SO FAR RANGE FROM ABOUT 1 TO 4 INCHES ABOVE 7500 FT. THE LATEST HRRR SOLUTION AGREES THE CURRENT PLUME WILL SHIFT SE OVER CENTRAL NM THRU THIS EVENING THEN INTO SOUTHERN NM LATE TONIGHT. A SECONDARY VORT MAX AHEAD OF THE MAIN UPPER COLD CORE WILL SHIFT OVER THE REGION TONIGHT AND EARLY SUNDAY...DELIVERING A SECONDARY PEAK IN PRECIP COVERAGE LATE TONIGHT AND EARLY SUNDAY. MODELS HAVE STRUGGLED WITH THE LOCATION AND INTENSITY OF THIS SECONDARY PRECIP MAX. HOWEVER...BASED ON TREND OF LATEST HRRR AFTER 06Z CONFIDENCE IS INCREASING THAT THE 12Z GFS AND ECMWF WILL VERIFY THIS MAX ALONG THE I-40/CONT DVD CORRIDOR INTO THE MIDDLE RIO GRANDE VALLEY AND NORTHERN MTS LATE TONIGHT. THE NE PLAINS WILL BE A TRICKY AREA AS WELL WITH SOME INCREDIBLE SPATIAL TEMPERATURE DIFFERENCES ON THE LATEST 21Z OBS. THE FRONT HAS PUSHED THROUGH TRINIDAD WHERE THE TEMP IS 21F WHILE RATON IS WINDY WITH A TEMP OF 61F! MODELS ARE TRENDING THE FRONT A LITTLE FARTHER SOUTH AND WEST BY EARLY SUNDAY SO EVENING SHIFT WILL NEED TO MONITOR FOR POSSIBLE EXPANSION OF ADVISORY SOUTH AND WEST. FOR THIS UPDATE WILL EXPAND ADVISORY INTO RATON RIDGE ZONE. MODEL PROFILES OVER THE NE SUGGEST A MIX OF SLEET...FREEZING RAIN...AND SNOW THRU AT LEAST EARLY SUNDAY MORNING BEFORE MID LEVEL COLDER AIR SLIDES OVER AND CHANGES ALL ACTIVITY TO SNOW. BEYOND SUNDAY...THERE ARE SEVERAL WEAK PERTURBATIONS IN WEST TO NW FLOW THAT WILL SLIDE QUICKLY OVER THE AREA. THIS WILL KEEP TEMPS NEAR SEASONAL AVERAGES WHILE WINDS ARE PERIODICALLY BREEZY OUT EAST. A FEW PERIODS OF THICK CLOUD COVER AND PERHAPS EVEN SOME SHOWERS ARE POSSIBLE FOR THE HIGH TERRAIN. GUYER && .FIRE WEATHER... MOIST PACIFIC TROUGH TO GRADUALLY CROSS THIS WEEKEND WITH WETTING PRECIPITATION CONTINUING TONIGHT AND SUNDAY. SNOW LEVELS HAVE ALREADY SHOWN SIGNS OF BEGINNING A DOWNWARD TREND THIS AFTERNOON...AND THESE WILL CONTINUE TO LOWER TO AROUND 6000 FEET ACROSS THE CONTINENTAL DIVIDE REGION AND UPPER RIO GRANDE VALLEY TONIGHT. A BAND OF MAINLY WINTER PRECIPITATION IS EXPECTED TO SET UP TONIGHT ACROSS THE CONTINENTAL DIVIDE REGION OF NW NM...BRINGING ACCUMULATING SNOW TO THAT AREA. FARTHER SOUTHEAST ACROSS THE SOUTHWEST MOUNTAINS AND CENTRAL MOUNTAIN CHAIN...THE SNOW ACCUMULATION LEVEL MAY ONLY DROP TO ABOUT 7000 FEET TONIGHT INTO SUNDAY MORNING. THE HIGH TERRAIN WILL REALLY BENEFIT FROM THE DWELL TIME OF ALL THIS MOISTURE WITH SEVERAL INCHES OF SNOW ACCUMULATION EXPECTED IN ALL NORTHERN AND CENTRAL NM MOUNTAINS ABOVE 7500 FEET. THE SAN JUAN MOUNTAINS SHOULD GET THE MOST SNOW WITH NEARLY 20 INCHES. A SECONDARY LOCATION FAVORED FOR ACCUMULATING WINTRY PRECIPITATION WILL BE THE NORTHEAST PLAINS AND QUAY COUNTY...WHERE A POTENT BACK DOOR COLD FRONT WILL PROVIDE A FOCUS FOR LIFT AS THE MOIST UPPER LEVEL TROUGH CROSSES. A FEW INCHES OF SNOW WITH SLEET AND EVEN SOME FREEZING RAIN ARE POSSIBLE THERE. HIGH TEMPERATURES ACROSS NORTHEAST AREAS WILL FALL 35 TO 40 DEGREES SUNDAY FROM TODAYS READINGS LEAVING HIGH TEMPERATURES IN THE MID 20S. STRONG WINDS ALONG AND EAST OF THE CENTRAL MOUNTAIN CHAIN THIS AFTERNOON WILL DIMINISH WITH SUNSET...EXCEPT FOR THE HIGHER PEAKS OF THE CENTRAL MOUNTAIN CHAIN WHERE GUSTY WINDS SHOULD LINGER THROUGH TONIGHT AS STRONGER FLOW ALOFT GRADUALLY SHIFTS EAST OF THE FORECAST AREA. TEMPERATURES WILL GENERALLY REBOUND THROUGH THURSDAY...WITH A NOTABLE EXCEPTION BEING SOME COOLER READINGS ACROSS THE NORTHEAST ON WEDNESDAY DUE TO A BACK DOOR COLD FRONT. MODELS ARE NOT AGREEING VERY WELL ON A WEAKER UPPER LEVEL TROUGH THAT MAY DIVE SOUTHEASTWARD OVER THE FORECAST AREA ON TUESDAY OR WEDNESDAY. AS HAS BEEN THE CASE THIS WINTER...THE ECMWF IS DEEPER/WETTER/SLOWER WHILE THE GFS IS SHALLOWER/DRIER/FASTER. GRIDS ARE ALIGNED WITH THE GFS SOLUTION FOR NOW. A WEAK RIDGE OF HIGH PRESSURE PROGGED TO CROSS THE FORECAST AREA WEDNESDAY NIGHT MAY QUICKLY TRANSITION TO GUSTY ZONAL FLOW ALOFT AS AN UPPER LEVEL TROUGH TRACKS SOUTHEASTWARD ACROSS THE CENTRAL ROCKIES. THIS SHOULD BE OUR NEXT DAY WITH WIND AND FIRE WEATHER CONCERNS. FORECAST GRIDS CURRENTLY SHOW THE TYPICAL PATCH OF CRITICAL CONDITIONS IN WESTERLY DOWNSLOPE FLOW AROUND CLINES CORNERS AND SANTA ROSA. HIGH TEMPERATURES SHOULD PEAK FROM 3 TO 8 DEGREES ABOVE NORMAL THURSDAY. VENTILATION-WISE...WATCH FOR POOR READINGS IN THE VICINITY OF THE BACK DOOR COLD FRONT ACROSS THE NORTHEAST TOMORROW...SUNDAY. ALSO...IN THE WAKE OF THIS WEEKENDS STORM SYSTEM...AREAS OF POOR VENTILATION WILL BE POSSIBLE FROM ALBUQUERQUE AND SANTA FE NORTHWESTWARD TO GALLUP AND FARMINGTON. FURTHER...THE UPPER LEVEL TROUGH TUESDAY/WEDNESDAY SHOULD BRING IN ENOUGH COOL AND SETTLED AIR FOR AREAS OF POOR VENTILATION ALONG AND WEST OF THE RIO GRANDE WEDNESDAY. 44 && .AVIATION... 18Z TAF CYCLE RAIN AND HIGH TERRAIN SNOW ALONG AND W OF THE CENTRAL MTN CHAIN TODAY WITH PERIODS OF MVFR AND BRIEF/LCL IFR CONDITIONS. SPOTTIER RAIN SHOWERS POSSIBLE FARTHER E...EXCEPT DRY ALONG/E OF A LINE FROM KROW TO KCVN. SNOW LEVEL SHOULD LOWER TO NEAR 8500 FEET DURING THE AFTN W OF THE RIO GRANDE. SNOW LEVEL WILL KEEP DROPPING TONIGHT...REACHING NEAR 6000 FT BY MORNING. AN EXCEPTION WILL BE LATE TONIGHT ACROSS NE/E CENTRAL AREAS WHERE A COLD FRONT WILL BRING MUCH COLDER TEMPERATURES AND A MIX OF SNOW...SLEET AND POSSIBLY -FZRA FM KTCC N TO THE CO BORDER. THIS SHOULD CHANGE OVER TO ALL SNOW ACROSS NE/E CENTRAL AREAS AFT SUNRISE. 44 && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 34 50 27 57 / 70 30 0 5 DULCE........................... 30 43 19 53 / 100 40 10 5 CUBA............................ 32 44 24 53 / 100 60 10 5 GALLUP.......................... 31 47 23 56 / 70 40 5 5 EL MORRO........................ 29 42 22 49 / 70 60 5 5 GRANTS.......................... 31 47 22 56 / 60 50 0 5 QUEMADO......................... 32 45 28 52 / 70 60 5 5 GLENWOOD........................ 38 56 24 63 / 90 30 0 5 CHAMA........................... 25 37 15 45 / 100 50 20 10 LOS ALAMOS...................... 32 45 32 51 / 90 70 10 5 PECOS........................... 31 45 24 48 / 80 70 10 5 CERRO/QUESTA.................... 27 41 16 51 / 80 60 10 5 RED RIVER....................... 23 32 17 40 / 90 70 20 5 ANGEL FIRE...................... 27 39 19 45 / 80 70 10 5 TAOS............................ 31 44 22 53 / 70 60 10 5 MORA............................ 31 43 21 50 / 80 70 10 5 ESPANOLA........................ 32 49 25 56 / 70 50 0 5 SANTA FE........................ 32 45 27 51 / 80 70 5 5 SANTA FE AIRPORT................ 34 48 28 55 / 70 60 5 5 ALBUQUERQUE FOOTHILLS........... 35 52 34 58 / 70 60 0 5 ALBUQUERQUE HEIGHTS............. 39 55 34 59 / 60 60 0 5 ALBUQUERQUE VALLEY.............. 42 56 29 61 / 60 50 0 0 ALBUQUERQUE WEST MESA........... 40 55 32 62 / 60 50 0 5 LOS LUNAS....................... 44 58 26 62 / 60 50 0 0 RIO RANCHO...................... 39 54 31 61 / 60 50 0 5 SOCORRO......................... 43 60 36 64 / 60 30 0 0 SANDIA PARK/CEDAR CREST......... 34 52 32 57 / 90 70 10 5 TIJERAS......................... 36 50 36 55 / 80 70 5 5 MORIARTY/ESTANCIA............... 34 52 28 54 / 80 70 5 0 CLINES CORNERS.................. 34 49 26 52 / 80 80 5 0 GRAN QUIVIRA.................... 37 55 31 54 / 90 50 5 5 CARRIZOZO....................... 40 55 32 58 / 90 50 0 5 RUIDOSO......................... 37 53 34 52 / 90 60 5 5 CAPULIN......................... 31 39 17 50 / 60 70 10 5 RATON........................... 30 45 18 56 / 50 60 10 5 SPRINGER........................ 31 47 19 57 / 40 60 5 0 LAS VEGAS....................... 32 45 21 54 / 70 60 10 0 CLAYTON......................... 18 25 14 49 / 60 60 5 5 ROY............................. 34 37 17 50 / 60 60 5 0 CONCHAS......................... 38 43 20 55 / 60 60 5 0 SANTA ROSA...................... 42 53 22 55 / 60 60 5 5 TUCUMCARI....................... 34 37 17 53 / 60 60 5 5 CLOVIS.......................... 40 45 16 50 / 50 60 5 0 PORTALES........................ 42 47 18 51 / 50 60 5 0 FORT SUMNER..................... 43 55 22 51 / 50 60 5 0 ROSWELL......................... 48 67 26 51 / 50 30 0 0 PICACHO......................... 43 61 26 53 / 50 40 5 0 ELK............................. 45 58 30 51 / 50 50 5 0 && .ABQ WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ502-508-510>515. WIND ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR THE FOLLOWING ZONES...NMZ521>524-526-528-529-532>537-539-540. WINTER WEATHER ADVISORY UNTIL 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ527-528-530-531-534. WINTER WEATHER ADVISORY UNTIL 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ503-504-506-516. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ505-507. WINTER STORM WARNING FROM 6 PM THIS EVENING TO 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ521-526. && $$ CORRECTED START TIME OF WINTER WEATHER ADVISORY FOR NORTHEAST ZONES
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
303 PM MST SAT MAR 1 2014 .SYNOPSIS... WIDESPREAD RAIN AND HIGH ELEVATION SNOW TODAY WILL GRADUALLY CHANGE OVER TO SNOW DOWN TO NEAR 6000 FEET TONIGHT BEFORE MIXING WITH RAIN AGAIN SUNDAY. SIGNIFICANT ACCUMULATIONS WILL OCCUR IN THE HIGHER TERRAIN OF THE NORTHERN AND WESTERN MOUNTAINS. STRONG WINDS OVER MUCH OF EASTERN NEW MEXICO WILL TAPER OFF THROUGH THE EVENING. A POTENT COLD FRONT OVER THE NORTHEAST PLAINS WILL ALLOW RAIN TO CHANGE OVER TO A MIX OF SNOW...SLEET...AND FREEZING RAIN THROUGH SUNDAY. THIS STORM SYSTEM WILL MOVE OUT OF THE AREA SUNDAY... LEAVING BEHIND COOLER TEMPERATURES THROUGH MONDAY. THE REMAINDER OF THE WEEK WILL BE NEAR NORMAL FOR EARLY MARCH AS A COUPLE WEAK DISTURBANCES MOVE OVER THE STATE. PERIODIC BREEZY CONDITIONS WILL IMPACT THE PLAINS AND PATCHY CLOUD COVER WITH EVEN A FEW SHOWERS WILL AFFECT THE HIGH TERRAIN. && .DISCUSSION... WHAT A WELCOME SITE IT IS AS A DEEP FETCH OF RAIN AND HIGH TERRAIN SNOW IMPACTS CENTRAL AND WESTERN NM. THE WATER VAPOR LOOP STILL SHOWS THE CORE OF A WELL-DEFINED STORM SYSTEM CRASHING ONSHORE SOUTHERN CALIFORNIA WITH A MASSIVE FETCH OF MOIST SW FLOW SHIFTING INTO AZ AND NM. CIRA TOTAL PWAT VALUES ARE ABOVE 200PCT OF NORMAL IN THIS PLUME AND IT WILL SHIFT DIRECTLY OVER NM THRU THIS EVENING. SFC AND MID LEVEL TEMPS ARE TRENDING DOWN WITH THE AID OF EVAPORATIONAL COOLING AND SOME WEAK COLD AIR ADVECTION. SNOW REPORTS SO FAR RANGE FROM ABOUT 1 TO 4 INCHES ABOVE 7500 FT. THE LATEST HRRR SOLUTION AGREES THE CURRENT PLUME WILL SHIFT SE OVER CENTRAL NM THRU THIS EVENING THEN INTO SOUTHERN NM LATE TONIGHT. A SECONDARY VORT MAX AHEAD OF THE MAIN UPPER COLD CORE WILL SHIFT OVER THE REGION TONIGHT AND EARLY SUNDAY...DELIVERING A SECONDARY PEAK IN PRECIP COVERAGE LATE TONIGHT AND EARLY SUNDAY. MODELS HAVE STRUGGLED WITH THE LOCATION AND INTENSITY OF THIS SECONDARY PRECIP MAX. HOWEVER...BASED ON TREND OF LATEST HRRR AFTER 06Z CONFIDENCE IS INCREASING THAT THE 12Z GFS AND ECMWF WILL VERIFY THIS MAX ALONG THE I-40/CONT DVD CORRIDOR INTO THE MIDDLE RIO GRANDE VALLEY AND NORTHERN MTS LATE TONIGHT. THE NE PLAINS WILL BE A TRICKY AREA AS WELL WITH SOME INCREDIBLE SPATIAL TEMPERATURE DIFFERENCES ON THE LATEST 21Z OBS. THE FRONT HAS PUSHED THROUGH TRINIDAD WHERE THE TEMP IS 21F WHILE RATON IS WINDY WITH A TEMP OF 61F! MODELS ARE TRENDING THE FRONT A LITTLE FARTHER SOUTH AND WEST BY EARLY SUNDAY SO EVENING SHIFT WILL NEED TO MONITOR FOR POSSIBLE EXPANSION OF ADVISORY SOUTH AND WEST. FOR THIS UPDATE WILL EXPAND ADVISORY INTO RATON RIDGE ZONE. MODEL PROFILES OVER THE NE SUGGEST A MIX OF SLEET...FREEZING RAIN...AND SNOW THRU AT LEAST EARLY SUNDAY MORNING BEFORE MID LEVEL COLDER AIR SLIDES OVER AND CHANGES ALL ACTIVITY TO SNOW. BEYOND SUNDAY...THERE ARE SEVERAL WEAK PERTURBATIONS IN WEST TO NW FLOW THAT WILL SLIDE QUICKLY OVER THE AREA. THIS WILL KEEP TEMPS NEAR SEASONAL AVERAGES WHILE WINDS ARE PERIODICALLY BREEZY OUT EAST. A FEW PERIODS OF THICK CLOUD COVER AND PERHAPS EVEN SOME SHOWERS ARE POSSIBLE FOR THE HIGH TERRAIN. GUYER && .FIRE WEATHER... MOIST PACIFIC TROUGH TO GRADUALLY CROSS THIS WEEKEND WITH WETTING PRECIPITATION CONTINUING TONIGHT AND SUNDAY. SNOW LEVELS HAVE ALREADY SHOWN SIGNS OF BEGINNING A DOWNWARD TREND THIS AFTERNOON...AND THESE WILL CONTINUE TO LOWER TO AROUND 6000 FEET ACROSS THE CONTINENTAL DIVIDE REGION AND UPPER RIO GRANDE VALLEY TONIGHT. A BAND OF MAINLY WINTER PRECIPITATION IS EXPECTED TO SET UP TONIGHT ACROSS THE CONTINENTAL DIVIDE REGION OF NW NM...BRINGING ACCUMULATING SNOW TO THAT AREA. FARTHER SOUTHEAST ACROSS THE SOUTHWEST MOUNTAINS AND CENTRAL MOUNTAIN CHAIN...THE SNOW ACCUMULATION LEVEL MAY ONLY DROP TO ABOUT 7000 FEET TONIGHT INTO SUNDAY MORNING. THE HIGH TERRAIN WILL REALLY BENEFIT FROM THE DWELL TIME OF ALL THIS MOISTURE WITH SEVERAL INCHES OF SNOW ACCUMULATION EXPECTED IN ALL NORTHERN AND CENTRAL NM MOUNTAINS ABOVE 7500 FEET. THE SAN JUAN MOUNTAINS SHOULD GET THE MOST SNOW WITH NEARLY 20 INCHES. A SECONDARY LOCATION FAVORED FOR ACCUMULATING WINTRY PRECIPITATION WILL BE THE NORTHEAST PLAINS AND QUAY COUNTY...WHERE A POTENT BACK DOOR COLD FRONT WILL PROVIDE A FOCUS FOR LIFT AS THE MOIST UPPER LEVEL TROUGH CROSSES. A FEW INCHES OF SNOW WITH SLEET AND EVEN SOME FREEZING RAIN ARE POSSIBLE THERE. HIGH TEMPERATURES ACROSS NORTHEAST AREAS WILL FALL 35 TO 40 DEGREES SUNDAY FROM TODAYS READINGS LEAVING HIGH TEMPERATURES IN THE MID 20S. STRONG WINDS ALONG AND EAST OF THE CENTRAL MOUNTAIN CHAIN THIS AFTERNOON WILL DIMINISH WITH SUNSET...EXCEPT FOR THE HIGHER PEAKS OF THE CENTRAL MOUNTAIN CHAIN WHERE GUSTY WINDS SHOULD LINGER THROUGH TONIGHT AS STRONGER FLOW ALOFT GRADUALLY SHIFTS EAST OF THE FORECAST AREA. TEMPERATURES WILL GENERALLY REBOUND THROUGH THURSDAY...WITH A NOTABLE EXCEPTION BEING SOME COOLER READINGS ACROSS THE NORTHEAST ON WEDNESDAY DUE TO A BACK DOOR COLD FRONT. MODELS ARE NOT AGREEING VERY WELL ON A WEAKER UPPER LEVEL TROUGH THAT MAY DIVE SOUTHEASTWARD OVER THE FORECAST AREA ON TUESDAY OR WEDNESDAY. AS HAS BEEN THE CASE THIS WINTER...THE ECMWF IS DEEPER/WETTER/SLOWER WHILE THE GFS IS SHALLOWER/DRIER/FASTER. GRIDS ARE ALIGNED WITH THE GFS SOLUTION FOR NOW. A WEAK RIDGE OF HIGH PRESSURE PROGGED TO CROSS THE FORECAST AREA WEDNESDAY NIGHT MAY QUICKLY TRANSITION TO GUSTY ZONAL FLOW ALOFT AS AN UPPER LEVEL TROUGH TRACKS SOUTHEASTWARD ACROSS THE CENTRAL ROCKIES. THIS SHOULD BE OUR NEXT DAY WITH WIND AND FIRE WEATHER CONCERNS. FORECAST GRIDS CURRENTLY SHOW THE TYPICAL PATCH OF CRITICAL CONDITIONS IN WESTERLY DOWNSLOPE FLOW AROUND CLINES CORNERS AND SANTA ROSA. HIGH TEMPERATURES SHOULD PEAK FROM 3 TO 8 DEGREES ABOVE NORMAL THURSDAY. VENTILATION-WISE...WATCH FOR POOR READINGS IN THE VICINITY OF THE BACK DOOR COLD FRONT ACROSS THE NORTHEAST TOMORROW...SUNDAY. ALSO...IN THE WAKE OF THIS WEEKENDS STORM SYSTEM...AREAS OF POOR VENTILATION WILL BE POSSIBLE FROM ALBUQUERQUE AND SANTA FE NORTHWESTWARD TO GALLUP AND FARMINGTON. FURTHER...THE UPPER LEVEL TROUGH TUESDAY/WEDNESDAY SHOULD BRING IN ENOUGH COOL AND SETTLED AIR FOR AREAS OF POOR VENTILATION ALONG AND WEST OF THE RIO GRANDE WEDNESDAY. 44 && .AVIATION... 18Z TAF CYCLE RAIN AND HIGH TERRAIN SNOW ALONG AND W OF THE CENTRAL MTN CHAIN TODAY WITH PERIODS OF MVFR AND BRIEF/LCL IFR CONDITIONS. SPOTTIER RAIN SHOWERS POSSIBLE FARTHER E...EXCEPT DRY ALONG/E OF A LINE FROM KROW TO KCVN. SNOW LEVEL SHOULD LOWER TO NEAR 8500 FEET DURING THE AFTN W OF THE RIO GRANDE. SNOW LEVEL WILL KEEP DROPPING TONIGHT...REACHING NEAR 6000 FT BY MORNING. AN EXCEPTION WILL BE LATE TONIGHT ACROSS NE/E CENTRAL AREAS WHERE A COLD FRONT WILL BRING MUCH COLDER TEMPERATURES AND A MIX OF SNOW...SLEET AND POSSIBLY -FZRA FM KTCC N TO THE CO BORDER. THIS SHOULD CHANGE OVER TO ALL SNOW ACROSS NE/E CENTRAL AREAS AFT SUNRISE. 44 && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 34 50 27 57 / 70 30 0 5 DULCE........................... 30 43 19 53 / 100 40 10 5 CUBA............................ 32 44 24 53 / 100 60 10 5 GALLUP.......................... 31 47 23 56 / 70 40 5 5 EL MORRO........................ 29 42 22 49 / 70 60 5 5 GRANTS.......................... 31 47 22 56 / 60 50 0 5 QUEMADO......................... 32 45 28 52 / 70 60 5 5 GLENWOOD........................ 38 56 24 63 / 90 30 0 5 CHAMA........................... 25 37 15 45 / 100 50 20 10 LOS ALAMOS...................... 32 45 32 51 / 90 70 10 5 PECOS........................... 31 45 24 48 / 80 70 10 5 CERRO/QUESTA.................... 27 41 16 51 / 80 60 10 5 RED RIVER....................... 23 32 17 40 / 90 70 20 5 ANGEL FIRE...................... 27 39 19 45 / 80 70 10 5 TAOS............................ 31 44 22 53 / 70 60 10 5 MORA............................ 31 43 21 50 / 80 70 10 5 ESPANOLA........................ 32 49 25 56 / 70 50 0 5 SANTA FE........................ 32 45 27 51 / 80 70 5 5 SANTA FE AIRPORT................ 34 48 28 55 / 70 60 5 5 ALBUQUERQUE FOOTHILLS........... 35 52 34 58 / 70 60 0 5 ALBUQUERQUE HEIGHTS............. 39 55 34 59 / 60 60 0 5 ALBUQUERQUE VALLEY.............. 42 56 29 61 / 60 50 0 0 ALBUQUERQUE WEST MESA........... 40 55 32 62 / 60 50 0 5 LOS LUNAS....................... 44 58 26 62 / 60 50 0 0 RIO RANCHO...................... 39 54 31 61 / 60 50 0 5 SOCORRO......................... 43 60 36 64 / 60 30 0 0 SANDIA PARK/CEDAR CREST......... 34 52 32 57 / 90 70 10 5 TIJERAS......................... 36 50 36 55 / 80 70 5 5 MORIARTY/ESTANCIA............... 34 52 28 54 / 80 70 5 0 CLINES CORNERS.................. 34 49 26 52 / 80 80 5 0 GRAN QUIVIRA.................... 37 55 31 54 / 90 50 5 5 CARRIZOZO....................... 40 55 32 58 / 90 50 0 5 RUIDOSO......................... 37 53 34 52 / 90 60 5 5 CAPULIN......................... 31 39 17 50 / 60 70 10 5 RATON........................... 30 45 18 56 / 50 60 10 5 SPRINGER........................ 31 47 19 57 / 40 60 5 0 LAS VEGAS....................... 32 45 21 54 / 70 60 10 0 CLAYTON......................... 18 25 14 49 / 60 60 5 5 ROY............................. 34 37 17 50 / 60 60 5 0 CONCHAS......................... 38 43 20 55 / 60 60 5 0 SANTA ROSA...................... 42 53 22 55 / 60 60 5 5 TUCUMCARI....................... 34 37 17 53 / 60 60 5 5 CLOVIS.......................... 40 45 16 50 / 50 60 5 0 PORTALES........................ 42 47 18 51 / 50 60 5 0 FORT SUMNER..................... 43 55 22 51 / 50 60 5 0 ROSWELL......................... 48 67 26 51 / 50 30 0 0 PICACHO......................... 43 61 26 53 / 50 40 5 0 ELK............................. 45 58 30 51 / 50 50 5 0 && .ABQ WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ502-508-510>515. WIND ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR THE FOLLOWING ZONES...NMZ521>524-526-528-529-532>537-539-540. WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ527-528-530-531-534. WINTER WEATHER ADVISORY UNTIL 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ503-504-506-516. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ505-507. WINTER STORM WARNING FROM 6 PM THIS EVENING TO 4 PM MST SUNDAY FOR THE FOLLOWING ZONES...NMZ521-526. && $$
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
101 PM CST SAT MAR 1 2014 .UPDATE... ISSUED AT 101 PM CST SAT MAR 1 2014 TEMPS ARE FINALLY RISING A LITTLE BUT NOT LOOKING LIKE ANY LOCATION WILL GET ABOVE ZERO. ONLY POSSIBLE EXCEPTION MAY BE ACROSS THE FAR SOUTHWEST WHICH HAS THE LEAST AMOUNT OF SNOW. STILL SEEING THE MOST CLOUD COVER ACROSS THE SOUTH WITH A LOT OF SUN IN THE NORTH. NOT PLANNING ON ANY CHANGES FOR NOW. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 345 AM CST SAT MAR 1 2014 WIND CHILLS WILL BE THE MAIN CONCERN THIS PERIOD. 00Z MODELS ARE IN GOOD AGREEMENT AND WILL USE A BLEND FOR DETAILS. TODAY...A VERY COLD AIRMASS WITH 925MB TEMPS -30C TO -32C WILL SETTLE OVER THE REGION AS SFC HIGH PRESSURE BUILDS. MAX TEMPS TODAY WILL STRUGGLE TO REACH -10F TO -15F MOST AREAS. WINDS WILL BE LIGHTER...BUT STILL 5-10 KNOTS. ALTHOUGH WE LIKELY WILL NEED TO EXTEND THE WIND CHILL HEADLINES INTO THIS AFTERNOON AND TONIGHT...WILL PASS THIS DUTY TO THE DAY SHIFT. THERE IS AN AREA OF CLOUDS AND FLURRIES ACROSS SOUTHWEST MANITOBA ASSOCIATED WITH AN UPPER JET STREAK. RAP GUIDANCE INDICATES THESE CONDITIONS WILL PROPAGATE SOUTHEAST THROUGH THE DAY...ADJUSTED SKY GRIDS ACCORDINGLY (AND ADDED FLURRIES). TONIGHT-SUNDAY...HIGH PRESSURE CONTINUES TO ESTABLISH ITSELF. THIS SHOULD END WIND CHILL HEADLINES BY LATER SUNDAY AFTERNOON AS WINDS BECOME CALM. TEMPERATURES MAY BE SLIGHTLY WARMER ON SUNDAY...BUT STILL BELOW ZERO MOST AREAS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 345 AM CST SAT MAR 1 2014 SUNDAY NIGHT-MONDAY NIGHT...HIGH PRESSURE MOVES EAST AS A WEAK SHORTWAVE FROM THE PAC NW APPROACHES AND MOVES THROUGH THE REGION. TIMING AND QPF AMOUNTS STILL A BIT UNCERTAIN...BUT MOST GUIDANCE DOES INDICATE SOMETHING LATER MONDAY AFTERNOON INTO THE EVENING. SNOW AMTS APPEAR TOWARD THE LIGHTER SIDE. TEMPERATURES SHOULD CONTINUE THE GRADUAL WARMING TREND (BUT STILL WELL BELOW NORMAL VALUES). TUESDAY-FRIDAY...LONG WAVE PATTERN IS SPLIT WITH ZONAL FLOW ACROSS THE STATES. LONG WAVE UPPER LOW OVER THE CANADIAN ARCHIPELAGO MOVES TO THE NORTHWEST BY THE END OF THE PERIOD. LONG WAVE PATTERN AMPLIFIES BY THE END OF THE PERIOD WITH AN UPPER LEVEL RIDGE OVER THE WEST COAST AND LONG WAVE TROUGH OVER EASTERN NORTH AMERICA. THE GFS WAS FASTER THAN THE ECMWF THROUGH WED. THEN THE GFS WAS SLOWER WITH THE NEXT SHORT WAVE ACROSS SOUTHERN CANADA FOR THU AND FRI. THE ECMWF HAS BEEN TRENDING FASTER WHILE THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS. WILL KEEP YESTERDAY POPS FOR TUE. WILL KEEP YESTERDAYS POPS IN THE WEST FOR TUE NIGHT. WILL EXPAND POPS FARTHER WEST ON WED NIGHT. WILL TRIM BACK POPS IN THE SOUTH FOR THU NIGHT. HIGH TEMPS WERE INCREASED 3 TO 4 DEGREES FOR THU...A DEGREE OR SO FOR WED AND FRI AND NO CHANGE TO THU FROM YESTERDAYS RUN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 101 PM CST SAT MAR 1 2014 GOOD FLYING WEATHER WITH THE EXCEPTION OF THE COLD. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND CHILL ADVISORY UNTIL NOON CST SUNDAY FOR NDZ038-039-049-052- 053. WIND CHILL WARNING UNTIL NOON CST SUNDAY FOR NDZ006>008-014>016- 024-026>030-054. MN...WIND CHILL ADVISORY UNTIL NOON CST SUNDAY FOR MNZ003-024-027>032- 040. WIND CHILL WARNING UNTIL NOON CST SUNDAY FOR MNZ001-002-004>009- 013>017-022-023. && $$ UPDATE...GODON SHORT TERM...TG LONG TERM...TG/HOPPES AVIATION...GUST
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
944 AM CST SAT MAR 1 2014 .UPDATE... ISSUED AT 944 AM CST SAT MAR 1 2014 LOTS OF SUN TODAY WITH THE EXCEPTION OF THE FAR SOUTHERN FA. MAIN QUESTION TODAY IS HOW MUCH TEMP RECOVERY CAN OCCUR WITH EARLY MARCH SUN UNDER AN AIRMASS THAT STAYS BELOW -30C AT 925MB THRU THE DAY. TEMPS HAVE SHOWN VERY LITTLE SIGN OF RISING YET BUT WILL HAVE TO WATCH A WHILE LONGER TO SEE WHAT HAPPENS. FOR NOW WILL EXTEND THE WIND CHILL HEADLINES PAST 18Z TODAY INTO 18Z SUNDAY. WIND CHILLS MAY RISE BRIEFLY OUT OF WARNING CRITERIA ACROSS THE NORTH BUT WILL QUICKLY DROP BACK INTO THEM BY LATE AFTERNOON INTO THE EVENING. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 345 AM CST SAT MAR 1 2014 WIND CHILLS WILL BE THE MAIN CONCERN THIS PERIOD. 00Z MODELS ARE IN GOOD AGREEMENT AND WILL USE A BLEND FOR DETAILS. TODAY...A VERY COLD AIRMASS WITH 925MB TEMPS -30C TO -32C WILL SETTLE OVER THE REGION AS SFC HIGH PRESSURE BUILDS. MAX TEMPS TODAY WILL STRUGGLE TO REACH -10F TO -15F MOST AREAS. WINDS WILL BE LIGHTER...BUT STILL 5-10 KNOTS. ALTHOUGH WE LIKELY WILL NEED TO EXTEND THE WIND CHILL HEADLINES INTO THIS AFTERNOON AND TONIGHT...WILL PASS THIS DUTY TO THE DAY SHIFT. THERE IS AN AREA OF CLOUDS AND FLURRIES ACROSS SOUTHWEST MANITOBA ASSOCIATED WITH AN UPPER JET STREAK. RAP GUIDANCE INDICATES THESE CONDITIONS WILL PROPAGATE SOUTHEAST THROUGH THE DAY...ADJUSTED SKY GRIDS ACCORDINGLY (AND ADDED FLURRIES). TONIGHT-SUNDAY...HIGH PRESSURE CONTINUES TO ESTABLISH ITSELF. THIS SHOULD END WIND CHILL HEADLINES BY LATER SUNDAY AFTERNOON AS WINDS BECOME CALM. TEMPERATURES MAY BE SLIGHTLY WARMER ON SUNDAY...BUT STILL BELOW ZERO MOST AREAS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 345 AM CST SAT MAR 1 2014 SUNDAY NIGHT-MONDAY NIGHT...HIGH PRESSURE MOVES EAST AS A WEAK SHORTWAVE FROM THE PAC NW APPROACHES AND MOVES THROUGH THE REGION. TIMING AND QPF AMOUNTS STILL A BIT UNCERTAIN...BUT MOST GUIDANCE DOES INDICATE SOMETHING LATER MONDAY AFTERNOON INTO THE EVENING. SNOW AMTS APPEAR TOWARD THE LIGHTER SIDE. TEMPERATURES SHOULD CONTINUE THE GRADUAL WARMING TREND (BUT STILL WELL BELOW NORMAL VALUES). TUESDAY-FRIDAY...LONG WAVE PATTERN IS SPLIT WITH ZONAL FLOW ACROSS THE STATES. LONG WAVE UPPER LOW OVER THE CANADIAN ARCHIPELAGO MOVES TO THE NORTHWEST BY THE END OF THE PERIOD. LONG WAVE PATTERN AMPLIFIES BY THE END OF THE PERIOD WITH AN UPPER LEVEL RIDGE OVER THE WEST COAST AND LONG WAVE TROUGH OVER EASTERN NORTH AMERICA. THE GFS WAS FASTER THAN THE ECMWF THROUGH WED. THEN THE GFS WAS SLOWER WITH THE NEXT SHORT WAVE ACROSS SOUTHERN CANADA FOR THU AND FRI. THE ECMWF HAS BEEN TRENDING FASTER WHILE THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS. WILL KEEP YESTERDAY POPS FOR TUE. WILL KEEP YESTERDAYS POPS IN THE WEST FOR TUE NIGHT. WILL EXPAND POPS FARTHER WEST ON WED NIGHT. WILL TRIM BACK POPS IN THE SOUTH FOR THU NIGHT. HIGH TEMPS WERE INCREASED 3 TO 4 DEGREES FOR THU...A DEGREE OR SO FOR WED AND FRI AND NO CHANGE TO THU FROM YESTERDAYS RUN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 625 AM CST SAT MAR 1 2014 VFR CONDITIONS SHOULD CONTINUE THROUGH THIS TAF PERIOD. COULD BE SCATTERED VFR CIGS THIS AFTERNOON...AND POSSIBLY FLURRIES. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND CHILL ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR NDZ038-039- 049-052-053. WIND CHILL WARNING UNTIL 1 PM CST THIS AFTERNOON FOR NDZ006>008- 014>016-024-026>030-054. MN...WIND CHILL ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR MNZ003-024- 027>032-040. WIND CHILL WARNING UNTIL 1 PM CST THIS AFTERNOON FOR MNZ001-002- 004>009-013>017-022-023. && $$ UPDATE...GODON SHORT TERM...TG LONG TERM...TG/HOPPES AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
625 AM CST SAT MAR 1 2014 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 345 AM CST SAT MAR 1 2014 WIND CHILLS WILL BE THE MAIN CONCERN THIS PERIOD. 00Z MODELS ARE IN GOOD AGREEMENT AND WILL USE A BLEND FOR DETAILS. TODAY...A VERY COLD AIRMASS WITH 925MB TEMPS -30C TO -32C WILL SETTLE OVER THE REGION AS SFC HIGH PRESSURE BUILDS. MAX TEMPS TODAY WILL STRUGGLE TO REACH -10F TO -15F MOST AREAS. WINDS WILL BE LIGHTER...BUT STILL 5-10 KNOTS. ALTHOUGH WE LIKELY WILL NEED TO EXTEND THE WIND CHILL HEADLINES INTO THIS AFTERNOON AND TONIGHT...WILL PASS THIS DUTY TO THE DAY SHIFT. THERE IS AN AREA OF CLOUDS AND FLURRIES ACROSS SOUTHWEST MANITOBA ASSOCIATED WITH AN UPPER JET STREAK. RAP GUIDANCE INDICATES THESE CONDITIONS WILL PROPAGATE SOUTHEAST THROUGH THE DAY...ADJUSTED SKY GRIDS ACCORDINGLY (AND ADDED FLURRIES). TONIGHT-SUNDAY...HIGH PRESSURE CONTINUES TO ESTABLISH ITSELF. THIS SHOULD END WIND CHILL HEADLINES BY LATER SUNDAY AFTERNOON AS WINDS BECOME CALM. TEMPERATURES MAY BE SLIGHTLY WARMER ON SUNDAY...BUT STILL BELOW ZERO MOST AREAS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 345 AM CST SAT MAR 1 2014 SUNDAY NIGHT-MONDAY NIGHT...HIGH PRESSURE MOVES EAST AS A WEAK SHORTWAVE FROM THE PAC NW APPROACHES AND MOVES THROUGH THE REGION. TIMING AND QPF AMOUNTS STILL A BIT UNCERTAIN...BUT MOST GUIDANCE DOES INDICATE SOMETHING LATER MONDAY AFTERNOON INTO THE EVENING. SNOW AMTS APPEAR TOWARD THE LIGHTER SIDE. TEMPERATURES SHOULD CONTINUE THE GRADUAL WARMING TREND (BUT STILL WELL BELOW NORMAL VALUES). TUESDAY-FRIDAY...LONG WAVE PATTERN IS SPLIT WITH ZONAL FLOW ACROSS THE STATES. LONG WAVE UPPER LOW OVER THE CANADIAN ARCHIPELAGO MOVES TO THE NORTHWEST BY THE END OF THE PERIOD. LONG WAVE PATTERN AMPLIFIES BY THE END OF THE PERIOD WITH AN UPPER LEVEL RIDGE OVER THE WEST COAST AND LONG WAVE TROUGH OVER EASTERN NORTH AMERICA. THE GFS WAS FASTER THAN THE ECMWF THROUGH WED. THEN THE GFS WAS SLOWER WITH THE NEXT SHORT WAVE ACROSS SOUTHERN CANADA FOR THU AND FRI. THE ECMWF HAS BEEN TRENDING FASTER WHILE THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS. WILL KEEP YESTERDAY POPS FOR TUE. WILL KEEP YESTERDAYS POPS IN THE WEST FOR TUE NIGHT. WILL EXPAND POPS FARTHER WEST ON WED NIGHT. WILL TRIM BACK POPS IN THE SOUTH FOR THU NIGHT. HIGH TEMPS WERE INCREASED 3 TO 4 DEGREES FOR THU...A DEGREE OR SO FOR WED AND FRI AND NO CHANGE TO THU FROM YESTERDAYS RUN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 625 AM CST SAT MAR 1 2014 VFR CONDITIONS SHOULD CONTINUE THROUGH THIS TAF PERIOD. COULD BE SCATTERED VFR CIGS THIS AFTERNOON...AND POSSIBLY FLURRIES. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND CHILL ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR NDZ038-039- 049-052-053. WIND CHILL WARNING UNTIL 1 PM CST THIS AFTERNOON FOR NDZ006>008- 014>016-024-026>030-054. MN...WIND CHILL ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR MNZ003-024- 027>032-040. WIND CHILL WARNING UNTIL 1 PM CST THIS AFTERNOON FOR MNZ001-002- 004>009-013>017-022-023. && $$ SHORT TERM...TG LONG TERM...TG/HOPPES AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
345 AM CST SAT MAR 1 2014 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 345 AM CST SAT MAR 1 2014 WIND CHILLS WILL BE THE MAIN CONCERN THIS PERIOD. 00Z MODELS ARE IN GOOD AGREEMENT AND WILL USE A BLEND FOR DETAILS. TODAY...A VERY COLD AIRMASS WITH 925MB TEMPS -30C TO -32C WILL SETTLE OVER THE REGION AS SFC HIGH PRESSURE BUILDS. MAX TEMPS TODAY WILL STRUGGLE TO REACH -10F TO -15F MOST AREAS. WINDS WILL BE LIGHTER...BUT STILL 5-10 KNOTS. ALTHOUGH WE LIKELY WILL NEED TO EXTEND THE WIND CHILL HEADLINES INTO THIS AFTERNOON AND TONIGHT...WILL PASS THIS DUTY TO THE DAY SHIFT. THERE IS AN AREA OF CLOUDS AND FLURRIES ACROSS SOUTHWEST MANITOBA ASSOCIATED WITH AN UPPER JET STREAK. RAP GUIDANCE INDICATES THESE CONDITIONS WILL PROPAGATE SOUTHEAST THROUGH THE DAY...ADJUSTED SKY GRIDS ACCORDINGLY (AND ADDED FLURRIES). TONIGHT-SUNDAY...HIGH PRESSURE CONTINUES TO ESTABLISH ITSELF. THIS SHOULD END WIND CHILL HEADLINES BY LATER SUNDAY AFTERNOON AS WINDS BECOME CALM. TEMPERATURES MAY BE SLIGHTLY WARMER ON SUNDAY...BUT STILL BELOW ZERO MOST AREAS. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 345 AM CST SAT MAR 1 2014 SUNDAY NIGHT-MONDAY NIGHT...HIGH PRESSURE MOVES EAST AS A WEAK SHORTWAVE FROM THE PAC NW APPROACHES AND MOVES THROUGH THE REGION. TIMING AND QPF AMOUNTS STILL A BIT UNCERTAIN...BUT MOST GUIDANCE DOES INDICATE SOMETHING LATER MONDAY AFTERNOON INTO THE EVENING. SNOW AMTS APPEAR TOWARD THE LIGHTER SIDE. TEMPERATURES SHOULD CONTINUE THE GRADUAL WARMING TREND (BUT STILL WELL BELOW NORMAL VALUES). TUESDAY-FRIDAY...LONG WAVE PATTERN IS SPLIT WITH ZONAL FLOW ACROSS THE STATES. LONG WAVE UPPER LOW OVER THE CANADIAN ARCHIPELAGO MOVES TO THE NORTHWEST BY THE END OF THE PERIOD. LONG WAVE PATTERN AMPLIFIES BY THE END OF THE PERIOD WITH AN UPPER LEVEL RIDGE OVER THE WEST COAST AND LONG WAVE TROUGH OVER EASTERN NORTH AMERICA. THE GFS WAS FASTER THAN THE ECMWF THROUGH WED. THEN THE GFS WAS SLOWER WITH THE NEXT SHORT WAVE ACROSS SOUTHERN CANADA FOR THU AND FRI. THE ECMWF HAS BEEN TRENDING FASTER WHILE THE GFS HAS TRENDED SLOWER. WILL BLEND THE TWO MODELS. WILL KEEP YESTERDAY POPS FOR TUE. WILL KEEP YESTERDAYS POPS IN THE WEST FOR TUE NIGHT. WILL EXPAND POPS FARTHER WEST ON WED NIGHT. WILL TRIM BACK POPS IN THE SOUTH FOR THU NIGHT. HIGH TEMPS WERE INCREASED 3 TO 4 DEGREES FOR THU...A DEGREE OR SO FOR WED AND FRI AND NO CHANGE TO THU FROM YESTERDAYS RUN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1115 PM CST FRI FEB 28 2014 VFR CONDITIONS EXPECTED WITH WINDS SLOWLY SHIFTING MORE WESTERLY BY SATURDAY AFTERNOON. THERE IS A BAND OF VFR CIGS IN CANADA THAT COULD MOVE THROUGH TOMORROW...BUT MODELS DISSIPATE THESE CLOUDS AND HAVE NOT MENTIONED THEM BUT SOMETHING TO KEEP IN MIND. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...WIND CHILL ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR NDZ038-039- 049-052-053. WIND CHILL WARNING UNTIL 1 PM CST THIS AFTERNOON FOR NDZ006>008- 014>016-024-026>030-054. MN...WIND CHILL ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR MNZ003-024- 027>032-040. WIND CHILL WARNING UNTIL 1 PM CST THIS AFTERNOON FOR MNZ001-002- 004>009-013>017-022-023. && $$ SHORT TERM...TG LONG TERM...TG/HOPPES AVIATION...DK
AREA FORECAST DISCUSSION
NWS NORMAN OK
937 PM CST SUN MAR 2 2014 .UPDATE... UPPER LOW CONTINUES TO MOVE EAST ACROSS OKLAHOMA. THE DRY SLOT WRAPPING AROUND THE LOW HAS EFFECTIVELY ENDED SIGNIFICANT PRECIPITATION ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS... ALTHOUGH THERE IS STILL SOME LIGHT PRECIPITATION BEING REPORTED IN PORTIONS OF SOUTH CENTRAL/SOUTHEAST OKLAHOMA DESPITE THE LACK OF RADAR ECHOES. FARTHER NORTH... THE PRECIPITATION CONTINUES WITH SOME RECENT REDEVELOPMENT OBSERVED IN WEST CENTRAL OKLAHOMA. MAY STILL SEE SOME ACCUMULATING SNOW IN NORTH CENTRAL OKLAHOMA UNDERNEATH THE PIVOT POINT OF THE PRECIPITATION BANDS IN THE NORTH. WILL KEEP THE CURRENT WARNING IN PLACE IN THE NORTH AT THIS TIME /ALTHOUGH WE HAD WHITTLED AWAY AT THE HEADLINES EARLIER THIS EVENING/. && .PREV DISCUSSION... /ISSUED 603 PM CST SUN MAR 2 2014/ AVIATION... THE LAST BAND OF SLEET AND SNOW WILL MOVE EAST OF CENTRAL OKLAHOMA BY MIDNIGHT. MVFR CEILINGS WILL BE WIDESPREAD UNTIL MONDAY AFTERNOON. GUSTY NORTH WIND WILL GRADUALLY DIMINISH BY LATE MORNING MONDAY. PREV DISCUSSION... /ISSUED 245 PM CST SUN MAR 2 2014/ DISCUSSION... A MULTI-FACETED WINTER WEATHER MESS CONTINUES TO AFFECT OKLAHOMA AND NORTH TEXAS. WV SATELLITE SHOWS A FAIRLY IMPRESSIVE UPPER LEVEL STORM SYSTEM DEEPENING ACROSS THE TX/OK PANHANDLES...WITH WELL PRONOUNCED DRY SLOT ENTERING WRN OK...AND AREA OF DEFORMATION/BANDED SNOW OVER THE OK/TX PANHANDLES. AHEAD OF THIS AREA OF MID LEVEL DRY AIR...SCT SNOW/SLEET SHOWERS ALONG WITH CONVECTIVE ELEMENTS CONTAINING HAIL CONTINUE. INSTABILITY REMAINS TOO MARGINAL FOR SEVERE HAIL...BUT SEVERAL REPORTS OF DIMES AND NICKELS HAVE COME IN. EXPECT THE LIKLIHOOD OF HAIL TO WANE THROUGH LATE AFTERNOON...BUT HEAVY SLEET CAN BE EXPECTED WITH ANY BOOMERS THAT HAPPEN TO AFFECT YOUR LOCATION. IN FACT...SLEETFALL RATES OF ONE HALF TO ONE INCH PER HOUR ARE PROBABLE WITH THE STRONGEST CONVECTIVE CORES. HOWEVER...THESE RATES WILL GENERALLY BE FEW AND FAR BETWEEN...AND EXPECT LIGHT TO MODERATE SLEET AND SNOW TO PERSIST INTO TONIGHT. THE HIGH-RES HRRR CONTINUES TO SUGGEST PERHAPS THE HEAVIEST SLEET WILL FALL OVER EXTREME SOUTH CENTRAL AND SOUTHEAST OKLAHOMA LATE THIS AFTERNOON AND EVENING...AND CONFIDENCE IN MORE WIDESPREAD HALF INCH OR GREATER SLEET ACCUMULATIONS IN THIS AREA WARRANTED A WINTER STORM WARNING. AREAS OF CENTRAL AND SOUTHWESTERN OKLAHOMA...AND WESTERN NORTH TEXAS HAVE CERTAINLY SEEN SLEET AND SNOW ACCUMULATIONS...BUT CONFIDENCE IS LOW THAT WSW CRITERIA WILL BE MET ON A LARGE SCALE...THUS WILL MAINTAIN THE ADVISORY FOR NOW. FARTHER NORTH AND WEST OVER NORTHWESTERN AND NORTH-CENTRAL OKLAHOMA HAVE THE BETTER CHANCES OF SUBSTANTIAL SNOW ACCUMULATIONS. HAVE OPTED TO MAINTAIN CURRENT WINTER STORM WARNING IN THESE AREAS...THOUGH SEVERAL MODELS HAVE SHIFTED THE HEAVIER SNOW SLIGHTLY FARTHER SOUTH...AND WILL HAVE TO KEEP A CLOSE EYE ON RADAR TRENDS AND OBSERVATIONS. THE STORM SYSTEM SHOULD GRADUALLY WORK EAST OF THE AREA OVERNIGHT TONIGHT...BUT SOME LINGERING LIGHT SNOW WILL LIKELY CARRY INTO THE WEE MORNING HOURS TOMORROW. ONCE WE GET TO SUNRISE TOMORROW...THE MAIN STORY WILL BE THE BITTERLY COLD TEMPERATURES AND WIND CHILLS. SINGLE DIGIT TO NEAR ZERO LOWS ARE FORECAST OVER A GOOD PART OF OKLAHOMA...WITH LOWER TEENS OVER SOUTHERN OKLAHOMA AND NORTH TEXAS. THIS COMBINED WITH NORTH WINDS WILL RESULT IN WIND CHILLS FROM NEAR ZERO SOUTH TO -15 DEGREES NORTH. THUS...HAVE ISSUED A WIND CHILL ADVISORY FOR MUCH OF OKLAHOMA. HIGHS WILL STRUGGLE INTO THE 20S AND 30S TOMORROW...SO DON`T EXPECT A LOT OF MELTING. ROAD CONDITIONS WILL LIKELY REMAIN SLICK AND HAZARDOUS RIGHT THROUGH TOMORROW AFTERNOON. ONCE WE GET THROUGH TOMORROW...THINGS ARE LOOKING UP. YES...IT WILL STILL BE CHILLY WEDNESDAY...BUT THE OVERALL TREND IS POSITIVE AS FAR AS TEMPS GO. MODELS BRING A WEAK UPPER WAVE OVER THE SOUTHERN PLAINS SOMETIME WEDNESDAY OR WEDNESDAY NIGHT...ANY PRECIP THAT ACCOMPANIES THIS SHOULD MAINLY FALL IN LIQUID FORM...THOUGH PARTS OF NORTHERN OKLAHOMA MAY GET A RAIN/SNOW MIX. TEMPERATURES WILL THEN WARM EACH DAY THROUGH LATE WEEK...WITH ANOTHER SHOT OF COLD AIR JUST IN TIME FOR NEXT WEEKEND. WELCOME TO WINTER IN MARCH EVERYONE! && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 7 24 17 46 / 50 0 10 10 HOBART OK 5 27 18 49 / 30 0 10 0 WICHITA FALLS TX 12 32 22 50 / 10 0 10 10 GAGE OK -2 25 19 48 / 60 0 10 0 PONCA CITY OK 3 20 13 41 / 100 0 10 0 DURANT OK 13 28 23 46 / 30 0 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR OKZ013- 017>020-023>032-040>043-046>048-050>052. WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR OKZ004>036-038- 040-042. WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR OKZ004>008- 010>012. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS NORMAN OK
603 PM CST SUN MAR 2 2014 .AVIATION... THE LAST BAND OF SLEET AND SNOW WILL MOVE EAST OF CENTRAL OKLAHOMA BY MIDNIGHT. MVFR CEILINGS WILL BE WIDESPREAD UNTIL MONDAY AFTERNOON. GUSTY NORTH WIND WILL GRADUALLY DIMINISH BY LATE MORNING MONDAY. && .PREV DISCUSSION... /ISSUED 245 PM CST SUN MAR 2 2014/ DISCUSSION... A MULTI-FACETED WINTER WEATHER MESS CONTINUES TO AFFECT OKLAHOMA AND NORTH TEXAS. WV SATELLITE SHOWS A FAIRLY IMPRESSIVE UPPER LEVEL STORM SYSTEM DEEPENING ACROSS THE TX/OK PANHANDLES...WITH WELL PRONOUNCED DRY SLOT ENTERING WRN OK...AND AREA OF DEFORMATION/BANDED SNOW OVER THE OK/TX PANHANDLES. AHEAD OF THIS AREA OF MID LEVEL DRY AIR...SCT SNOW/SLEET SHOWERS ALONG WITH CONVECTIVE ELEMENTS CONTAINING HAIL CONTINUE. INSTABILITY REMAINS TOO MARGINAL FOR SEVERE HAIL...BUT SEVERAL REPORTS OF DIMES AND NICKELS HAVE COME IN. EXPECT THE LIKLIHOOD OF HAIL TO WANE THROUGH LATE AFTERNOON...BUT HEAVY SLEET CAN BE EXPECTED WITH ANY BOOMERS THAT HAPPEN TO AFFECT YOUR LOCATION. IN FACT...SLEETFALL RATES OF ONE HALF TO ONE INCH PER HOUR ARE PROBABLE WITH THE STRONGEST CONVECTIVE CORES. HOWEVER...THESE RATES WILL GENERALLY BE FEW AND FAR BETWEEN...AND EXPECT LIGHT TO MODERATE SLEET AND SNOW TO PERSIST INTO TONIGHT. THE HIGH-RES HRRR CONTINUES TO SUGGEST PERHAPS THE HEAVIEST SLEET WILL FALL OVER EXTREME SOUTH CENTRAL AND SOUTHEAST OKLAHOMA LATE THIS AFTERNOON AND EVENING...AND CONFIDENCE IN MORE WIDESPREAD HALF INCH OR GREATER SLEET ACCUMULATIONS IN THIS AREA WARRANTED A WINTER STORM WARNING. AREAS OF CENTRAL AND SOUTHWESTERN OKLAHOMA...AND WESTERN NORTH TEXAS HAVE CERTAINLY SEEN SLEET AND SNOW ACCUMULATIONS...BUT CONFIDENCE IS LOW THAT WSW CRITERIA WILL BE MET ON A LARGE SCALE...THUS WILL MAINTAIN THE ADVISORY FOR NOW. FARTHER NORTH AND WEST OVER NORTHWESTERN AND NORTH-CENTRAL OKLAHOMA HAVE THE BETTER CHANCES OF SUBSTANTIAL SNOW ACCUMULATIONS. HAVE OPTED TO MAINTAIN CURRENT WINTER STORM WARNING IN THESE AREAS...THOUGH SEVERAL MODELS HAVE SHIFTED THE HEAVIER SNOW SLIGHTLY FARTHER SOUTH...AND WILL HAVE TO KEEP A CLOSE EYE ON RADAR TRENDS AND OBSERVATIONS. THE STORM SYSTEM SHOULD GRADUALLY WORK EAST OF THE AREA OVERNIGHT TONIGHT...BUT SOME LINGERING LIGHT SNOW WILL LIKELY CARRY INTO THE WEE MORNING HOURS TOMORROW. ONCE WE GET TO SUNRISE TOMORROW...THE MAIN STORY WILL BE THE BITTERLY COLD TEMPERATURES AND WIND CHILLS. SINGLE DIGIT TO NEAR ZERO LOWS ARE FORECAST OVER A GOOD PART OF OKLAHOMA...WITH LOWER TEENS OVER SOUTHERN OKLAHOMA AND NORTH TEXAS. THIS COMBINED WITH NORTH WINDS WILL RESULT IN WIND CHILLS FROM NEAR ZERO SOUTH TO -15 DEGREES NORTH. THUS...HAVE ISSUED A WIND CHILL ADVISORY FOR MUCH OF OKLAHOMA. HIGHS WILL STRUGGLE INTO THE 20S AND 30S TOMORROW...SO DON`T EXPECT A LOT OF MELTING. ROAD CONDITIONS WILL LIKELY REMAIN SLICK AND HAZARDOUS RIGHT THROUGH TOMORROW AFTERNOON. ONCE WE GET THROUGH TOMORROW...THINGS ARE LOOKING UP. YES...IT WILL STILL BE CHILLY WEDNESDAY...BUT THE OVERALL TREND IS POSITIVE AS FAR AS TEMPS GO. MODELS BRING A WEAK UPPER WAVE OVER THE SOUTHERN PLAINS SOMETIME WEDNESDAY OR WEDNESDAY NIGHT...ANY PRECIP THAT ACCOMPANIES THIS SHOULD MAINLY FALL IN LIQUID FORM...THOUGH PARTS OF NORTHERN OKLAHOMA MAY GET A RAIN/SNOW MIX. TEMPERATURES WILL THEN WARM EACH DAY THROUGH LATE WEEK...WITH ANOTHER SHOT OF COLD AIR JUST IN TIME FOR NEXT WEEKEND. WELCOME TO WINTER IN MARCH EVERYONE! && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 7 24 17 46 / 70 0 10 10 HOBART OK 5 27 18 49 / 50 0 10 0 WICHITA FALLS TX 12 32 22 50 / 10 0 10 10 GAGE OK -2 25 19 48 / 70 0 10 0 PONCA CITY OK 3 20 13 41 / 90 0 10 0 DURANT OK 13 28 23 46 / 40 0 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR OKZ013- 014-016>030-033>040-044-045. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST MONDAY FOR OKZ004>036-038-040-042. WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR OKZ004>012- 015-031-032-041>043-046>048-050>052. TX...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR TXZ083>090. && $$ 26/09/09
AREA FORECAST DISCUSSION
NWS TULSA OK
530 PM CST SUN MAR 2 2014 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. IFR CONDITIONS WILL REMAIN THE NORM FOR MUCH OF THE EVENING AND OVERNIGHT AS UPPER LOW CONTINUES TO SLIDE EAST ACROSS THE AREA. BAND OF HEAVIER CONVECTIVE CELLS WILL MOVE OUT OF W ARKANSAS SHORTLY BUT THERE REMAINS A CHANCE OF THUNDER AT KFSM THROUGH ABOUT 02. OTHERWISE...AFTER A BRIEF BREAK IN THE PRECIP ASSOCIATED WITH DRY SLOT...MAIN PRECIP TYPE WILL QUICKLY BECOME SNOW THIS EVENING AS LOW MOVES OVERHEAD...WITH PRECIP ENDING FROM W TO E FROM ABOUT 06-08Z. IMPROVEMENT TO MVFR SHOULD OCCUR SOON AFTER SNOW ENDS WITH VFR IN ALL LOCATIONS BY MONDAY AFTERNOON. && .PREV DISCUSSION... /ISSUED 448 PM CST SUN MAR 2 2014/ DISCUSSION... TODAY I`VE SEEN MORE DIVERSE AND RAPIDLY CHANGING WEATHER THAN IN ANY EIGHT HOUR SHIFT OVER MY ENTIRE 40 YEAR CAREER. THICK COLD ARCTIC AIR OF 5 TO 6 THOUSAND FEET HAS PRODUCED SNOW AT MOST LOCATIONS TODAY. LIFT ABOVE A DEEP WARM LAYER ALOFT HAS PRODUCED THUNDERSTORMS WITH MANY COMBINATIONS OF SLEET SNOW RAIN FREEZING RAIN HAIL. DEEPENING COLD LAYER HAS ABOUT SHUT-OUT FREEZING RAIN RISK SO ICE STORM WARNING HAS BEEN CONVERTED TO A WINTER STORM HEADLINE. ALL WARNINGS CONSOLIDATED TO END AT 4 AM...WITH A WIND CHILL ADVISORY UNTIL NOON MONDAY. LAST SNOW SLEET BURST CURRENTLY NOW WEST OF I-35 WILL MOVE THROUGH THIS EVENING FOR MOST OF EASTERN OKLAHOMA AND LATE EVENING TO 4 AM NORTHWEST ARKANSAS. HRRR SHORT RANGE MODEL WHICH HAS BEEN GOOD...CLEARS PRECIP FROM CARROLL COUNTY AR JUST BEFORE 4 AM. BITTER COLD AND WINDY MONDAY REQUIRES WIND CHILL HEADLINE. HIGHS TEMPS MONDAY NEAR RECORD LOW/MAXIMUM. NEXT WAVE WEDNESDAY/WEDNESDAY NIGHT MORE SIGNIFICANT WAVE NEXT WEEKEND. GW && .TSA WATCHES/WARNINGS/ADVISORIES... OK...WINTER STORM WARNING UNTIL 4 AM MONDAY FOR OKZ049-OKZ053-OKZ054- OKZ055-OKZ056-OKZ057-OKZ058-OKZ059-OKZ060-OKZ061-OKZ062- OKZ063-OKZ064-OKZ065-OKZ066-OKZ067-OKZ068-OKZ069-OKZ070- OKZ071-OKZ072-OKZ073-OKZ074-OKZ075-OKZ076. WIND CHILL ADVISORY FROM 4 AM MONDAY TO NOON MONDAY FOR OKZ049- OKZ054-OKZ055-OKZ056-OKZ057-OKZ058-OKZ059-OKZ060-OKZ061- OKZ062-OKZ063-OKZ064-OKZ065-OKZ066-OKZ067-OKZ068-OKZ069- OKZ070-OKZ071-OKZ072-OKZ073-OKZ074-OKZ075-OKZ076. AR...WIND CHILL ADVISORY FROM 4 AM MONDAY TO NOON MONDAY FOR ARZ001- ARZ002-ARZ010-ARZ011-ARZ019-ARZ020-ARZ029. WINTER STORM WARNING UNTIL 4 AM MONDAY FOR ARZ001-ARZ002-ARZ010- ARZ011-ARZ019-ARZ020-ARZ029. && $$ SHORT TERM...99 LONG TERM....99 AVIATION...14
AREA FORECAST DISCUSSION
NWS TULSA OK
1126 AM CST SAT MAR 1 2014 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. WIDESPREAD MVFR/OCCASIONAL IFR CIGS WILL PERSIST THROUGH THE AFTERNOON...ALTHOUGH COULD SEE A FEW BREAKS FROM TIME TO TIME. IFR CIGS WILL PREVAIL THIS EVENING THROUGH SUNDAY MORNING...WITH FREEZING RAIN/SLEET DEVELOPING AFTER 06Z ACROSS NE OK/NW AR...THEN INTO SE OK/WCNTRL AR TOWARD 12Z. && .PREV DISCUSSION... /ISSUED 1104 AM CST SAT MAR 1 2014/ ..UPDATE... DISCUSSION... LEAD COLD FRONT HAS PUSHED INTO NRN TX...WITH AN EXPANSIVE AREA OF LOW CLOUDS TO THE N OF THE FRONT ACROSS OUR FORECAST AREA. HRRR SUGGESTS CLOUD DECK WILL PERSIST THROUGH THE AFTERNOON...ESPECIALLY ACROSS SE OK...SO HAVE LOWERED HIGH TEMPERATURES SEVERAL DEGREES ACROS THIS AREA. && .PRELIMINARY POINT TEMPS/POPS... TUL 49 20 20 7 / 10 60 80 60 FSM 55 38 38 18 / 10 40 80 60 MLC 54 29 29 13 / 10 30 70 20 BVO 37 13 16 4 / 10 70 80 60 FYV 55 28 28 8 / 10 60 90 80 BYV 54 25 25 6 / 10 60 90 80 MKO 55 25 25 10 / 10 50 80 60 MIO 45 16 17 2 / 10 70 80 70 F10 50 24 24 9 / 10 50 70 50 HHW 57 42 42 19 / 10 20 70 20 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...WINTER STORM WARNING FROM 6 PM SATURDAY TO MIDNIGHT MONDAY FOR OKZ049-OKZ054-OKZ055-OKZ056-OKZ057-OKZ058-OKZ059-OKZ060- OKZ061-OKZ062-OKZ063-OKZ067-OKZ068-OKZ069-OKZ070-OKZ071- OKZ072-OKZ073-OKZ074-OKZ075-OKZ076. WINTER WEATHER ADVISORY FROM 6 AM SUNDAY TO MIDNIGHT MONDAY FOR OKZ053. WINTER STORM WATCH FROM 6 PM SATURDAY TO MIDNIGHT MONDAY FOR OKZ064-OKZ065-OKZ066. AR...WINTER STORM WARNING FROM 6 PM SATURDAY TO MIDNIGHT MONDAY FOR ARZ001-ARZ002-ARZ010-ARZ011-ARZ019-ARZ020-ARZ029. && $$ AVIATION...18
AREA FORECAST DISCUSSION
NWS TULSA OK
1104 AM CST SAT MAR 1 2014 ...UPDATE... .DISCUSSION... LEAD COLD FRONT HAS PUSHED INTO NRN TX...WITH AN EXPANSIVE AREA OF LOW CLOUDS TO THE N OF THE FRONT ACROSS OUR FORECAST AREA. HRRR SUGGESTS CLOUD DECK WILL PERSIST THROUGH THE AFTERNOON...ESPECIALLY ACROSS SE OK...SO HAVE LOWERED HIGH TEMPERATURES SEVERAL DEGREES ACROS THIS AREA. && .PRELIMINARY POINT TEMPS/POPS... TUL 49 20 20 7 / 10 60 80 60 FSM 55 38 38 18 / 10 40 80 60 MLC 54 29 29 13 / 10 30 70 20 BVO 37 13 16 4 / 10 70 80 60 FYV 55 28 28 8 / 10 60 90 80 BYV 54 25 25 6 / 10 60 90 80 MKO 55 25 25 10 / 10 50 80 60 MIO 45 16 17 2 / 10 70 80 70 F10 50 24 24 9 / 10 50 70 50 HHW 57 42 42 19 / 10 20 70 20 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...WINTER STORM WARNING FROM 6 PM SATURDAY TO MIDNIGHT MONDAY FOR OKZ049-OKZ054-OKZ055-OKZ056-OKZ057-OKZ058-OKZ059-OKZ060- OKZ061-OKZ062-OKZ063-OKZ067-OKZ068-OKZ069-OKZ070-OKZ071- OKZ072-OKZ073-OKZ074-OKZ075-OKZ076. WINTER WEATHER ADVISORY FROM 6 AM SUNDAY TO MIDNIGHT MONDAY FOR OKZ053. WINTER STORM WATCH FROM 6 PM SATURDAY TO MIDNIGHT MONDAY FOR OKZ064-OKZ065-OKZ066. AR...WINTER STORM WARNING FROM 6 PM SATURDAY TO MIDNIGHT MONDAY FOR ARZ001-ARZ002-ARZ010-ARZ011-ARZ019-ARZ020-ARZ029. && $$ SHORT TERM...18 LONG TERM....21
AREA FORECAST DISCUSSION
NWS PORTLAND OR
1002 AM PST SAT MAR 1 2014 .SYNOPSIS...STRONG LOW PRESSURE IS DRIFTING INTO SOUTHERN CALIFORNIA THIS MORNING. LEFTOVER MOISTURE FROM AN ASSOCIATED FRONT CONTINUES TO BRING RAIN AND HIGH ELEVATION SNOW TO PORTIONS OF LANE AND LINN COUNTIES. OTHERWISE THE BIG STORY TODAY WILL BE A STRONG PUSH OF COLD AIR COMING DOWN FROM THE CANADIAN ROCKIES. A BACKDOOR COLD FRONT HAS PUSHED SOUTHWEST ACROSS THE COLUMBIA BASIN...AND HAS ARRIVED ALONG THE EAST SLOPES OF THE CASCADES. THIS FRONT WILL PUSH WESTWARD THROUGH THE GORGE AND ACROSS THE PORTLAND METRO AREA TODAY WITH COLD EAST WINDS TO FOLLOW LATER TODAY THROUGH SUNDAY. WHILE IT DOES NOT APPEAR IT WILL BE COLD ENOUGH FOR WINTRY PRECIP IN THE PORTLAND METRO AREA...THERE IS A THREAT FOR SIGNIFICANT SNOW AND ICE IN THE GORGE AND HOOD RIVER VALLEY TONIGHT UNTIL THE COLD AIR SCOURS OUT SUNDAY NIGHT OR MONDAY. OTHERWISE...A SERIES OF PACIFIC STORM SYSTEMS WILL BRING PERIODS OF RAIN...MOUNTAIN SNOW...AND COASTAL WIND FOR MUCH OF THE UPCOMING WEEK. && .MORNING UPDATE...COMPLICATED FORECAST WITH CLASH OF MARINE AND CONTINENTAL AIR UNDERWAY. THE HIGHEST IMPACT EVENT IN THE NEXT FEW DAYS IS THE POTENTIAL FOR ICE ACCUMULATIONS IN THE COLUMBIA RIVER GORGE AND THE UPPER HOOD RIVER VALLEY. SINCE NAM SOUNDINGS ARE NOT HELPFUL AT THE MOMENT WILL RELY ON 4KM WRFGFS A BIT MORE HEAVILY TODAY AS IT HAS A DECENT HANDLE AT LEAST ON HOOD RIVER CURRENTLY UNTIL OBSERVATIONS SUPPORT OTHERWISE. OBSERVATIONS CURRENTLY SUGGEST PROFILES ARE COLD ENOUGH FOR SNOW TO FALL IN UPPER HOOD RIVER VALLEY...AND SURFACE TEMPERATURES NEAR HOOD RIVER ARE NOW IN THE LOWER TO MID 30S. WHILE TEMPERATURES ARE EXPECTED TO FALL SOME MORE TODAY...PRECIPITATION AMOUNTS ARE NOT EXPECTED TO BE TOO HIGH THROUGH THE DAY GIVEN THE SHALLOW MOISTURE PROFILES. ADVISORY LEVEL SNOWS IN THE UPPER HOOD RIVER VALLEY ARE 3-6 INCHES IN 12 HOURS...WITH 1 INCH PLUS IN THE GORGE. WITH BORDERLINE TEMPS ONGOING NEAR HOOD RIVER CURRENTLY EXPECT THAT RATES WON`T BE SUFFICIENT TODAY BUT... CURRENT ADVISORY IS BUMPED UP AS SNOW IS STICKING FROM CASCADE LOCKS TO CARSON.I DO NOT THINK THE UPPER HOOD RIVER VALLEY WILL GET 3-6" OF SNOW BASED ON EXPECTED QPF BUT THE GORGE 1" CRITERIA WILL BE EASIER TO BE FOUND EVEN THOUGH THE PRECIP SHIELD IS NOT COMPLETELY FILLED IN. EXPECT IT WILL BE MORE SQUALLY IN NATURE IS OCCURRING WHICH CAN CAUSE TRICKY TRAVEL QUICKLY...THUS THE REASON FOR BUMPING UP THE START TIME. SOUNDING PROFILES SUGGEST SNOW IS THE DOMINANT P-TYPE OVERNIGHT CLOSER TO HOOD RIVER...WITH A TRANSITION EARLIER IN THE WESTERN COLUMBIA RIVER GORGE...BUT STILL SOME UNCERTAINTY THERE WITH SEVERAL MODELS WHILE STRUGGLING WITH SURFACE TEMPS STILL SUGGEST A WARM NOSE RIDING OVER THE LOWER LEVEL COLD AIR. THEREFORE WILL HOLD ONTO THE ADVISORY FOR ALL LOCATIONS. WITH SOME NEAR SURFACE WET BULBING IT IS POSSIBLE THAT SOME FROZEN PRECIPITATION (SLEET/SNOW GRAINS) MAY GET IN TO NEAR TTD/EAST PDX BUT NOT THE MOST LIKELY SCENARIO AT THIS POINT AS EVEN THE DALLES RAPID TEMPERATURE DROPS HAVE EASED SOME. OUR TEMPERATURE AT THE OFFICE 3 MILES WEST OF PDX CONTINUES TO FALL...CURRENTLY APPROACHING 36 DEGREES. QPF COMPARISONS FOR 12Z-18Z TOMORROW MORNING RANGE FROM 0.1 TO 0.4 OVER THE GORGE AND UPPER HOOD VALLEY. SOUNDINGS SUGGEST THAT THIS IS THE MOST LIKELY PERIOD OF TRANSITION TO A SLEET AND FREEZING RAIN PROFILE FOR THE CENTRAL GORGE. EVEN THE COLD BIASED NAM HAS TEMPERATURES WARMING ABOVE FREEZING IN THE GORGE SOMETIME LATE TOMORROW AFTERNOON. IT IS THIS KEY TRANSITION PERIOD WHEN SIGNIFICANT PRECIPITATION IS EXPECTED TO BE COMING IN. WILL TRIM BACK THE END OF THE WATCH SOME. IT IS LIKELY TO TRANSITION MUCH SOONER THAN CURRENT EXPIRATION TIME WEST OF CASCADE LOCKS...BUT WILL HANDLE THAT LATER TODAY WHEN WE DECIDE WHAT TO DO WITH THE WATCH. WITH THE WIND ADVISORY...THIS IS JUST AN EAST COUNTY SITUATION AT BEST. PEAK WINDS LOOK TO BE TODAY SO THE ADVISORY MAY BE A BIT A LONG. /KMD && .SHORT TERM...TODAY THROUGH MONDAY...LET ME START OFF BY SAYING THIS IS ONE OF THE MOST CHALLENGING FORECASTS THUS FAR IN MY CAREER...AS IT IS A VERY ODD PATTERN WHERE A MAJOR SURGE OF COLD AIR MAY OR MAY NOT BE SUCCESSFUL PUSHING ALL THE WAY SOUTHWEST FROM THE CANADIAN PRAIRIE PROVINCES ACROSS BOTH THE ROCKIES AND CASCADES. THIS IS VERY TOUGH FOR COLD AIR TO DO SUCCESSFULLY...BUT IT IS POSSIBLE AND MOST MODELS HAVE BEEN FAIRLY CONSISTENT IN SUGGESTING IT WILL. SOME MODELS SUCH AS THE NAM STILL SUGGEST THERE COULD BE WINTRY PRECIPITATION IN THE PORTLAND METRO AREA LATER TODAY INTO EARLY SUNDAY...WHILE OTHERS SUCH AS THE RAP ARE NOT EVEN BRINGING ENOUGH COLD AIR TO CREATE A SIGNIFICANT SNOW/ICE EVENT IN THE GORGE OR HOOD RIVER VALLEY. TO GIVE AN EXAMPLE OF THE UNCERTAINTY HERE...THE 06Z NAM BUFR SOUNDING SUGGESTED TEMPS WILL BE IN THE LOW 20S IN HOOD RIVER AT 3 PM THIS AFTERNOON. MEANWHILE THE 06Z RAP SUGGESTS TEMPS WILL BE IN THE UPPER 40S AT THE SAME PLACE AT THE SAME TIME. I BELIEVE BOTH ARE WRONG...STICKING TO THE TYPICAL BIASES OF THE NAM BEING TOO COLD AND THE RAP BEING TOO WARM. THE REALITY WILL MOST LIKELY SOMEWHERE IN BETWEEN THESE EXTREMES. NEEDLESS TO SAY CONFIDENCE IN ANY DETERMINISTIC FORECAST IS UNUSUALLY LOW IN THIS SITUATION...BUT WE WILL DO OUR BEST. LETS START WITH THE TWO MODELS I MENTIONED EARLIER...THE NAM AND THE RAP. THE COLD AIR IS ALREADY WELL BEHIND THE 00Z NAM FORECAST AND EVEN THE 06Z INITIALIZATION. CHECKING SFC PRESSURES...THE 09Z NAM FORECAST FOR CENTRAL WA ARE ALREADY 4-6 MB TOO HIGH. TEMPS REMAIN ABOVE FREEZING FOR ALL BUT THE EASTERN THIRD OF WASHINGTON...EXCEPT MOSES LAKE AND EPHRATA. THE 06Z NAM BUFR SOUNDING FOR KDLS SAID IT WOULD BE 28 DEG F BY NOW...THE 11Z OB FOR KDLS SAYS IT IS STILL 42. THIS MARKS LITTLE CHANGE FROM WHERE THE TEMP HAS BEEN SITTING AT KDLS MUCH OF THE NIGHT. HOWEVER THE COLD ADVECTION HAS JUST STARTED... EAST WINDS AT 10 KT HAVE PICKED UP AND THE DEWPOINT FELL 7 DEG F IN ONE HOUR. SO IT IS SAFE TO SAY OUR BACKDOOR COLD FRONT HAS PUSHED W-SW INTO THE COLUMBIA GORGE...BUT IS DOING SO MUCH SLOWER AND WITH MUCH LESS BLUSTER THAN THE NAM SUGGESTED. MEANWHILE THE RAP HAS BEEN DOING MUCH BETTER WITH THE HANDLING OF THE COLD AIR...BEING MUCH SLOWER AS IT HAS THE BENEFIT OF BEING REINITIALIZED EACH HOUR. WHERE THE RAP LIKELY GOES WRONG IS WHAT IT DOES WITH THE COLD AIR LATER TODAY. STRANGELY...THE RAP HAS THE EASTSIDE COLD POOL ESSENTIALLY SURRENDERING LATER TODAY DUE TO INCREASING WESTERLY FLOW ALOFT AND SUPPOSED WARM ADVECTION IN BRITISH COLUMBIA ASSOCIATED WITH A DISTURBANCE SLIDING DOWN THE COAST. THIS DISTURBANCE APPEARS FAR TOO WEAK TO DEFEAT A FULL-ON PUSH OF ARCTIC AIR...AND THE RAP IS OUT ON ITS OWN WITH THIS IDEA. SUSPECT THE EASTSIDE COLD POOL WILL CONTINUE TO STRENGTHEN OVER THE NEXT 12-24 HRS AS THE NAM/GFS/UKMET/ ECMWF/GEM ALL INDICATE TO SOME DEGREE. THE 00Z/06Z GFS ALSO HAS DONE MUCH BETTER WITH ITS INITIALIZATION... BOTH WITH SFC PRESSURES AND THE MAGNITUDE/PROGRESS OF THE COLD AIR. IT ALSO SEEMS TO BE HANDLING THE STRONG LOW OFF CALIFORNIA AND ACTIVITY FURTHER OUT INTO THE PACIFIC FAIRLY WELL. THEREFORE THE LATEST RUNS OF THE GFS ARE PREFERRED...AND ESSENTIALLY OUR FORECAST IS A BLEND BETWEEN THE PREVIOUS FORECAST AND THE GFS/WRFGFS. WE DECIDED TO PUSH BACK THE START OF THE WINTER WX ADVISORY IN THE GORGE TO 6 PM FOR SEVERAL REASONS. FIRST...THE DELAY IN ARRIVAL OF COLD AIR. SECOND...THE UNCERTAINTY IN THE AMOUNT OF QPF EXPECTED TODAY. AND THIRD...THE EARLY MARCH SUN AND ITS IMPACT ON SURFACE TEMPS. TEMPS HAVE GENERALLY BEEN IN THE 40S ALL NIGHT...SO SURFACES TAKE SOME TIME TO COOL OFF ENOUGH TO ALLOW ICE ACCRETION. THE STRONGER EARLY MARCH SUN WILL BE FIGHTING THE COLD AIR...EVEN THOUGH IT WILL LIKELY BE CLOUDY THROUGHOUT THE DAY THERE WILL LIKELY BE ENOUGH SOLAR ENERGY TO KEEP MOST SURFACES ABOVE FREEZING THROUGHOUT THE DAY. OUTSIDE OF THE GORGE...TODAY WILL SEE RAIN GRADUALLY INCREASING ACROSS THE AREA DUE TO LOW AND MID-LEVEL FRONTOGENESIS ASSOCIATED WITH THE BACKDOOR COLD FRONT MEETING THE MILD AND MOIST AIR MASS IN PLACE. AS COLD HIGH PRESSURE BUILDS EAST OF THE CASCADES...EASTERLY PRES GRADIENTS AND THUS EAST WINDS WILL INCREASE THROUGH THE GORGE. THIS SHOULD CAUSE TEMPS TO STAY STEADY OR SLOWLY FALL THROUGH THE DAY IN THE PDX METRO AREA...WHILE AREAS OUTSIDE OF THE GORGE OUTFLOW ONCE AGAIN AIM FOR THE 50S. IT APPEARS VERY QUESTIONABLE WINDS WILL BE STRONG ENOUGH FOR AN ADVISORY...BUT THERE IS ENOUGH UNCERTAINTY IN THIS SITUATION TO KEEP THE EXISTING WIND ADVISORY IN PLACE FOR THE EAST PORTLAND METRO. NORTHEAST WINDS ASSOCIATED WITH THE COLD ADVECTION ARE RATHER STRONG IN THE COLUMBIA BASIN...IT WILL BE INTERESTING TO SEE WHAT THEY DO THIS MORNING WHEN THEY REACH THE CASCADES. THE COLD POOL WILL LIKELY BE DEEP ENOUGH TO SUPPORT A WINDY DAY FOR MUCH OF THE METRO...RATHER THAN CONFINE STRONGER WINDS TO THE GORGE. EXPECT MANY SPOTS IN AND AROUND PORTLAND/VANCOUVER WILL SEE GUSTS IN THE 30-40 MPH RANGE...WITH PERHAPS AN ISOLATED 45 MPH GUST OR TWO. THE RESULTING DOWNSLOPING OF THE BROADER EAST WIND MAY ALSO TAKE A BIT OF THE EDGE OFF THE MAGNITUDE OF THE COLD AIR TRYING TO SPILL WEST OF THE CASCADES. AS A RESULT WE BUMPED TEMPS UP SLIGHTLY TODAY...AND LEFT ONLY A SLIGHT CHANCE OF FZRA AROUND TROUTDALE TONIGHT. KEEP IN MIND THE NAM BUFR SOUNDINGS CONTINUE TO SUGGEST A HIGH IMPACT ICE EVENT THROUGHOUT THE METRO THIS AFTERNOON THROUGH SUNDAY MORNING...BUT AGAIN THE NAM HAS BEEN DISCOUNTED DUE TO THE FACT IT IS FAR TOO FAST AND STRONG WITH THE EASTSIDE COLD AIR. A PACIFIC DISTURBANCE WILL BEGIN TO SPREAD MORE RAIN ACROSS THE DISTRICT SUNDAY. AS THE LOW PRESSURE SYSTEM APPROACHES...THERE MAY BE A BIT OF A COASTAL JET WHICH WOULD ALLOW BRIEF WINDS GUSTING 40-50 MPH ALONG THE BEACHES AND HEADLANDS. ANOTHER SIMILAR SYSTEM IS EXPECTED FOR MONDAY...AND THESE SYSTEMS WILL HAVE AN INCREASING TAP OF SUBTROPICAL MOISTURE. THIS MOISTURE WILL BE OVERRUNNING THE COLD AIR IN THE GORGE AND HOOD RIVER VALLEY... POSSIBLY RESULTING IN SUBSTANTIAL SNOW AND ICE ACCUMULATIONS BEFORE THE COLD AIR FINALLY SCOURS OUT MONDAY. AT THIS MOMENT OUR HUNCH IS THAT TEMPS WILL MODERATE JUST ENOUGH SUNDAY TO ALLOW THE SECOND SURGE OF MOISTURE TO FALL AS PLAIN RAIN IN THE GORGE AND NEAR HOOD RIVER. AGAIN...LEFT THE EXISTING WINTER STORM WATCH IN PLACE DUE TO THE UNCERTAINTY... BUT IT APPEARS THE BEST CHANCE FOR WINTRY PRECIP SUN NIGHT/MON WILL BE IN UPPER PORTIONS OF THE HOOD RIVER VALLEY AND POSSIBLY EASTERN SKAMANIA COUNTY. TEMPS WARM WELL INTO THE 50S ON GUSTY SOUTH WINDS THROUGH THE WILLAMETTE VALLEY MONDAY...POSSIBLY INTO THE 40S AND LOWER 50S IN THE GORGE BY MONDAY AFTERNOON OR EVENING. AN ACTIVE PACIFIC STORM TRACK WILL KEEP THINGS WET WELL INTO THE UPCOMING WEEK...BUT TEMPS WILL WARM UP JUST ENOUGH TO GIVE MANY OF US A HINT OF SPRING TO THE AIR BY MIDWEEK. WEAGLE .LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS... MONDAY NIGHT THROUGH FRIDAY...MILD BUT WET CONDITIONS ARE EXPECTED NEXT WEEK AS STRONG WESTERLY FLOW PREVAILS. A MOIST PACIFIC FRONTAL SYSTEM WILL MOVE ONSHORE LATE MONDAY...LIFTING SNOW LEVELS ABOVE PASS LEVEL. STRONG OROGRAPHIC LIFT WILL ALLOW ABUNDANT PRECIPITATION OVER THE CASCADES AND COAST RANGE MONDAY NIGHT INTO TUESDAY. BOTH THE 12Z GFS AND ECMWF ARE STILL IN GOOD AGREEMENT SHOWING BACK TO BACK SYSTEMS MOVING THROUGH WEDNESDAY AND THURSDAY. THEY BOTH SETUP AN UPPER LOW IN THE GULF OF ALASKA AND ANOTHER JUST OFF THE OREGON/CALIFORNIA BORDER. THE 12Z ECMWF HAS A 985 MB SURFACE LOW DEVELOPING LATE WEDNESDAY NIGHT AND HAS IT SETUP A LITTLE FURTHER SOUTH OF THE GFS SOLUTION. MAY SEE SOME DECENT COASTAL WINDS WITH THIS SETUP AS THE LOW LIFTS NORTH ALONG THE COAST THROUGH THURSDAY MORNING. POST FRONTAL SHOWERS CONTINUE INTO LATE NEXT WEEK AS MODELS SUGGEST AN AMPLIFYING TROUGH OVER THE PACIFIC NORTHWEST. /27 && .AVIATION...CONDITIONS ARE SLOWLY DETERIORATING THIS MORNING AS MOISTURE SPREADS INTO THE REGION FROM A STORM SYSTEM OFF THE CALIFORNIA COAST. AT CURRENT MOST COAST SITES SIT AT MVFR WITH SOME LOCALIZED IFR OR LOWER...WHILE IN THE WILLAMETTE VALLEY MVFR RULES ROUGHLY SOUTH OF KSLE WITH VFR TO THE NORTH. EXPECT THE MVFR CIGS TO CONTINUE SPREADING NORTH LATER THIS MORNING WITH SHOWER ACTIVITY INCREASING. PERSISTENT OFFSHORE FLOW WILL CONTINUE THROUGH THE REST OF TODAY OVER W WASHINGTON AND NW OREGON...WITH BREEZY TO GUSTY WINDS FOR AREAS N OF A KTMK TO KUAO LINE. KPDX AND APPROACHES...VFR AT CURRENT SHOULD LOWER TO MVFR LATER THIS MORNING. EXPECT GUSTY E WINDS THROUGH THE DAY...WITH THE STRONGEST WINDS AFFECTING THE EASTERN PART OF THE METRO AREA TOWARD THE COLUMBIA RIVER GORGE. PYLE && .MARINE...CONDITIONS WILL REMAIN FAIRLY BENIGN ACROSS THE COASTAL WATERS TODAY INTO EARLY SUN. LIGHT TO MODERATE OFFSHORE FLOW MAY BECOME GUSTY AT TIMES THIS AFTERNOON...WITH A FEW GUSTS UP TO 25 KT POSSIBLE...MAINLY BELOW THE COASTAL GAPS AND THROUGH THE COLUMBIA RIVER. A MORE ACTIVE WEATHER PATTERN LOOKS TO BEGIN LATER SUN/MON. A WARM FRONT WILL LIFT N ACROSS THE COASTAL WATERS SUN NIGHT INTO MON AM. A STRONG FRONT WILL ARRIVE TUE NIGHT...WITH INCREASING POTENTIAL OF SOUTHERLY GALES AT THAT TIME. REST OF WEEK WILL REMAIN BREEZY AND UNSETTLED AS MORE FRONTS ARRIVES. PYLE/ROCKEY && .PQR WATCHES/WARNINGS/ADVISORIES... OR...WIND ADVISORY UNTIL 6 AM PST SUNDAY FOR GREATER PORTLAND METRO AREA. WINTER WEATHER ADVISORY UNTIL 6 AM PST SUNDAY FOR CENTRAL COLUMBIA RIVER GORGE-UPPER HOOD RIVER VALLEY-WESTERN COLUMBIA RIVER GORGE. WINTER STORM WATCH FROM SUNDAY MORNING THROUGH LATE SUNDAY NIGHT FOR CENTRAL COLUMBIA RIVER GORGE-UPPER HOOD RIVER VALLEY- WESTERN COLUMBIA RIVER GORGE. WA...WIND ADVISORY UNTIL 6 AM PST SUNDAY FOR GREATER VANCOUVER AREA. WINTER WEATHER ADVISORY UNTIL 6 AM PST SUNDAY FOR CENTRAL COLUMBIA RIVER GORGE-WESTERN COLUMBIA RIVER GORGE. WINTER WEATHER ADVISORY UNTIL 6 AM PST SUNDAY FOR S WA CASCADES. WINTER STORM WATCH FROM SUNDAY MORNING THROUGH LATE SUNDAY NIGHT FOR CENTRAL COLUMBIA RIVER GORGE-SOUTH WASHINGTON CASCADES-WESTERN COLUMBIA RIVER GORGE. PZ...NONE. && $$ MORE WEATHER INFORMATION ONLINE AT.. HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV 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.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
435 AM PST SAT MAR 1 2014 ...CORRECTION TO AVIATION SECTION. .SYNOPSIS...STRONG LOW PRESSURE IS DRIFTING INTO SOUTHERN CALIFORNIA THIS MORNING. LEFTOVER MOISTURE FROM AN ASSOCIATED FRONT CONTINUES TO BRING RAIN AND HIGH ELEVATION SNOW TO PORTIONS OF LANE AND LINN COUNTIES. OTHERWISE THE BIG STORY TODAY WILL BE A STRONG PUSH OF COLD AIR COMING DOWN FROM THE CANADIAN ROCKIES. A BACKDOOR COLD FRONT HAS PUSHED SOUTHWEST ACROSS THE COLUMBIA BASIN...AND HAS ARRIVED ALONG THE EAST SLOPES OF THE CASCADES. THIS FRONT WILL PUSH WESTWARD THROUGH THE GORGE AND ACROSS THE PORTLAND METRO AREA TODAY WITH COLD EAST WINDS TO FOLLOW LATER TODAY THROUGH SUNDAY. WHILE IT DOES NOT APPEAR IT WILL BE COLD ENOUGH FOR WINTRY PRECIP IN THE PORTLAND METRO AREA...THERE IS A THREAT FOR SIGNIFICANT SNOW AND ICE IN THE GORGE AND HOOD RIVER VALLEY TONIGHT UNTIL THE COLD AIR SCOURS OUT SUNDAY NIGHT OR MONDAY. OTHERWISE...A SERIES OF PACIFIC STORM SYSTEMS WILL BRING PERIODS OF RAIN...MOUNTAIN SNOW...AND COASTAL WIND FOR MUCH OF THE UPCOMING WEEK. && .SHORT TERM...TODAY THROUGH MONDAY...LET ME START OFF BY SAYING THIS IS ONE OF THE MOST CHALLENGING FORECASTS THUS FAR IN MY CAREER...AS IT IS A VERY ODD PATTERN WHERE A MAJOR SURGE OF COLD AIR MAY OR MAY NOT BE SUCCESSFUL PUSHING ALL THE WAY SOUTHWEST FROM THE CANADIAN PRAIRIE PROVINCES ACROSS BOTH THE ROCKIES AND CASCADES. THIS IS VERY TOUGH FOR COLD AIR TO DO SUCCESSFULLY...BUT IT IS POSSIBLE AND MOST MODELS HAVE BEEN FAIRLY CONSISTENT IN SUGGESTING IT WILL. SOME MODELS SUCH AS THE NAM STILL SUGGEST THERE COULD BE WINTRY PRECIPITATION IN THE PORTLAND METRO AREA LATER TODAY INTO EARLY SUNDAY...WHILE OTHERS SUCH AS THE RAP ARE NOT EVEN BRINGING ENOUGH COLD AIR TO CREATE A SIGNIFICANT SNOW/ICE EVENT IN THE GORGE OR HOOD RIVER VALLEY. TO GIVE AN EXAMPLE OF THE UNCERTAINTY HERE...THE 06Z NAM BUFR SOUNDING SUGGESTED TEMPS WILL BE IN THE LOW 20S IN HOOD RIVER AT 3 PM THIS AFTERNOON. MEANWHILE THE 06Z RAP SUGGESTS TEMPS WILL BE IN THE UPPER 40S AT THE SAME PLACE AT THE SAME TIME. I BELIEVE BOTH ARE WRONG...STICKING TO THE TYPICAL BIASES OF THE NAM BEING TOO COLD AND THE RAP BEING TOO WARM. THE REALITY WILL MOST LIKELY SOMEWHERE IN BETWEEN THESE EXTREMES. NEEDLESS TO SAY CONFIDENCE IN ANY DETERMINISTIC FORECAST IS UNUSUALLY LOW IN THIS SITUATION...BUT WE WILL DO OUR BEST. LETS START WITH THE TWO MODELS I MENTIONED EARLIER...THE NAM AND THE RAP. THE COLD AIR IS ALREADY WELL BEHIND THE 00Z NAM FORECAST AND EVEN THE 06Z INITIALIZATION. CHECKING SFC PRESSURES...THE 09Z NAM FORECAST FOR CENTRAL WA ARE ALREADY 4-6 MB TOO HIGH. TEMPS REMAIN ABOVE FREEZING FOR ALL BUT THE EASTERN THIRD OF WASHINGTON...EXCEPT MOSES LAKE AND EPHRATA. THE 06Z NAM BUFR SOUNDING FOR KDLS SAID IT WOULD BE 28 DEG F BY NOW...THE 11Z OB FOR KDLS SAYS IT IS STILL 42. THIS MARKS LITTLE CHANGE FROM WHERE THE TEMP HAS BEEN SITTING AT KDLS MUCH OF THE NIGHT. HOWEVER THE COLD ADVECTION HAS JUST STARTED... EAST WINDS AT 10 KT HAVE PICKED UP AND THE DEWPOINT FELL 7 DEG F IN ONE HOUR. SO IT IS SAFE TO SAY OUR BACKDOOR COLD FRONT HAS PUSHED W-SW INTO THE COLUMBIA GORGE...BUT IS DOING SO MUCH SLOWER AND WITH MUCH LESS BLUSTER THAN THE NAM SUGGESTED. MEANWHILE THE RAP HAS BEEN DOING MUCH BETTER WITH THE HANDLING OF THE COLD AIR...BEING MUCH SLOWER AS IT HAS THE BENEFIT OF BEING REINITIALIZED EACH HOUR. WHERE THE RAP LIKELY GOES WRONG IS WHAT IT DOES WITH THE COLD AIR LATER TODAY. STRANGELY...THE RAP HAS THE EASTSIDE COLD POOL ESSENTIALLY SURRENDERING LATER TODAY DUE TO INCREASING WESTERLY FLOW ALOFT AND SUPPOSED WARM ADVECTION IN BRITISH COLUMBIA ASSOCIATED WITH A DISTURBANCE SLIDING DOWN THE COAST. THIS DISTURBANCE APPEARS FAR TOO WEAK TO DEFEAT A FULL-ON PUSH OF ARCTIC AIR...AND THE RAP IS OUT ON ITS OWN WITH THIS IDEA. SUSPECT THE EASTSIDE COLD POOL WILL CONTINUE TO STRENGTHEN OVER THE NEXT 12-24 HRS AS THE NAM/GFS/UKMET/ ECMWF/GEM ALL INDICATE TO SOME DEGREE. THE 00Z/06Z GFS ALSO HAS DONE MUCH BETTER WITH ITS INITIALIZATION... BOTH WITH SFC PRESSURES AND THE MAGNITUDE/PROGRESS OF THE COLD AIR. IT ALSO SEEMS TO BE HANDLING THE STRONG LOW OFF CALIFORNIA AND ACTIVITY FURTHER OUT INTO THE PACIFIC FAIRLY WELL. THEREFORE THE LATEST RUNS OF THE GFS ARE PREFERRED...AND ESSENTIALLY OUR FORECAST IS A BLEND BETWEEN THE PREVIOUS FORECAST AND THE GFS/WRFGFS. WE DECIDED TO PUSH BACK THE START OF THE WINTER WX ADVISORY IN THE GORGE TO 6 PM FOR SEVERAL REASONS. FIRST...THE DELAY IN ARRIVAL OF COLD AIR. SECOND...THE UNCERTAINTY IN THE AMOUNT OF QPF EXPECTED TODAY. AND THIRD...THE EARLY MARCH SUN AND ITS IMPACT ON SURFACE TEMPS. TEMPS HAVE GENERALLY BEEN IN THE 40S ALL NIGHT...SO SURFACES TAKE SOME TIME TO COOL OFF ENOUGH TO ALLOW ICE ACCRETION. THE STRONGER EARLY MARCH SUN WILL BE FIGHTING THE COLD AIR...EVEN THOUGH IT WILL LIKELY BE CLOUDY THROUGHOUT THE DAY THERE WILL LIKELY BE ENOUGH SOLAR ENERGY TO KEEP MOST SURFACES ABOVE FREEZING THROUGHOUT THE DAY. OUTSIDE OF THE GORGE...TODAY WILL SEE RAIN GRADUALLY INCREASING ACROSS THE AREA DUE TO LOW AND MID-LEVEL FRONTOGENESIS ASSOCIATED WITH THE BACKDOOR COLD FRONT MEETING THE MILD AND MOIST AIR MASS IN PLACE. AS COLD HIGH PRESSURE BUILDS EAST OF THE CASCADES...EASTERLY PRES GRADIENTS AND THUS EAST WINDS WILL INCREASE THROUGH THE GORGE. THIS SHOULD CAUSE TEMPS TO STAY STEADY OR SLOWLY FALL THROUGH THE DAY IN THE PDX METRO AREA...WHILE AREAS OUTSIDE OF THE GORGE OUTFLOW ONCE AGAIN AIM FOR THE 50S. IT APPEARS VERY QUESTIONABLE WINDS WILL BE STRONG ENOUGH FOR AN ADVISORY...BUT THERE IS ENOUGH UNCERTAINTY IN THIS SITUATION TO KEEP THE EXISTING WIND ADVISORY IN PLACE FOR THE EAST PORTLAND METRO. NORTHEAST WINDS ASSOCIATED WITH THE COLD ADVECTION ARE RATHER STRONG IN THE COLUMBIA BASIN...IT WILL BE INTERESTING TO SEE WHAT THEY DO THIS MORNING WHEN THEY REACH THE CASCADES. THE COLD POOL WILL LIKELY BE DEEP ENOUGH TO SUPPORT A WINDY DAY FOR MUCH OF THE METRO...RATHER THAN CONFINE STRONGER WINDS TO THE GORGE. EXPECT MANY SPOTS IN AND AROUND PORTLAND/VANCOUVER WILL SEE GUSTS IN THE 30-40 MPH RANGE...WITH PERHAPS AN ISOLATED 45 MPH GUST OR TWO. THE RESULTING DOWNSLOPING OF THE BROADER EAST WIND MAY ALSO TAKE A BIT OF THE EDGE OFF THE MAGNITUDE OF THE COLD AIR TRYING TO SPILL WEST OF THE CASCADES. AS A RESULT WE BUMPED TEMPS UP SLIGHTLY TODAY...AND LEFT ONLY A SLIGHT CHANCE OF FZRA AROUND TROUTDALE TONIGHT. KEEP IN MIND THE NAM BUFR SOUNDINGS CONTINUE TO SUGGEST A HIGH IMPACT ICE EVENT THROUGHOUT THE METRO THIS AFTERNOON THROUGH SUNDAY MORNING...BUT AGAIN THE NAM HAS BEEN DISCOUNTED DUE TO THE FACT IT IS FAR TOO FAST AND STRONG WITH THE EASTSIDE COLD AIR. A PACIFIC DISTURBANCE WILL BEGIN TO SPREAD MORE RAIN ACROSS THE DISTRICT SUNDAY. AS THE LOW PRESSURE SYSTEM APPROACHES...THERE MAY BE A BIT OF A COASTAL JET WHICH WOULD ALLOW BRIEF WINDS GUSTING 40-50 MPH ALONG THE BEACHES AND HEADLANDS. ANOTHER SIMILAR SYSTEM IS EXPECTED FOR MONDAY...AND THESE SYSTEMS WILL HAVE AN INCREASING TAP OF SUBTROPICAL MOISTURE. THIS MOISTURE WILL BE OVERRUNNING THE COLD AIR IN THE GORGE AND HOOD RIVER VALLEY... POSSIBLY RESULTING IN SUBSTANTIAL SNOW AND ICE ACCUMULATIONS BEFORE THE COLD AIR FINALLY SCOURS OUT MONDAY. AT THIS MOMENT OUR HUNCH IS THAT TEMPS WILL MODERATE JUST ENOUGH SUNDAY TO ALLOW THE SECOND SURGE OF MOISTURE TO FALL AS PLAIN RAIN IN THE GORGE AND NEAR HOOD RIVER. AGAIN...LEFT THE EXISTING WINTER STORM WATCH IN PLACE DUE TO THE UNCERTAINTY... BUT IT APPEARS THE BEST CHANCE FOR WINTRY PRECIP SUN NIGHT/MON WILL BE IN UPPER PORTIONS OF THE HOOD RIVER VALLEY AND POSSIBLY EASTERN SKAMANIA COUNTY. TEMPS WARM WELL INTO THE 50S ON GUSTY SOUTH WINDS THROUGH THE WILLAMETTE VALLEY MONDAY...POSSIBLY INTO THE 40S AND LOWER 50S IN THE GORGE BY MONDAY AFTERNOON OR EVENING. AN ACTIVE PACIFIC STORM TRACK WILL KEEP THINGS WET WELL INTO THE UPCOMING WEEK...BUT TEMPS WILL WARM UP JUST ENOUGH TO GIVE MANY OF US A HINT OF SPRING TO THE AIR BY MIDWEEK. WEAGLE .LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS... MONDAY NIGHT THROUGH FRIDAY...MILD BUT WET CONDITIONS ARE EXPECTED NEXT WEEK AS STRONG WESTERLY FLOW PREVAILS. A MOIST PACIFIC FRONTAL SYSTEM WILL MOVE ONSHORE LATE MONDAY...LIFTING SNOW LEVELS ABOVE PASS LEVEL. STRONG OROGRAPHIC LIFT WILL ALLOW ABUNDANT PRECIPITATION OVER THE CASCADES AND COAST RANGE MONDAY NIGHT INTO TUESDAY. BOTH THE 12Z GFS AND ECMWF ARE STILL IN GOOD AGREEMENT SHOWING BACK TO BACK SYSTEMS MOVING THROUGH WEDNESDAY AND THURSDAY. THEY BOTH SETUP AN UPPER LOW IN THE GULF OF ALASKA AND ANOTHER JUST OFF THE OREGON/CALIFORNIA BORDER. THE 12Z ECMWF HAS A 985 MB SURFACE LOW DEVELOPING LATE WEDNESDAY NIGHT AND HAS IT SETUP A LITTLE FURTHER SOUTH OF THE GFS SOLUTION. MAY SEE SOME DECENT COASTAL WINDS WITH THIS SETUP AS THE LOW LIFTS NORTH ALONG THE COAST THROUGH THURSDAY MORNING. POST FRONTAL SHOWERS CONTINUE INTO LATE NEXT WEEK AS MODELS SUGGEST AN AMPLIFYING TROUGH OVER THE PACIFIC NORTHWEST. /27 && .AVIATION...VFR ACROSS REGION THIS AM. HOWEVER...OCCASIONAL LIGHT RAIN WITH CIGS MVFR AND LOCALLY IFR S BETWEEN KS12 AND K61S...MOSTLY AFFECTING KEUG. NOT MUCH CHANGE TODAY WITH MOSTLY VFR ALONG THE COAST AND INLAND N OF KSLE. THAT SAID...CIGS WILL GRADUALLY LOWER ACROSS INLAND NW OREGON TODAY AS MORE MOISTURE ALOFT ARRIVES FROM THE S. OFFSHORE FLOW WILL GRADUALLY INCREASE TODAY OVER W WASHINGTON AND NW OREGON TODAY...WITH BREEZY WINDS FOR AREAS N OF A KTMK TO KUAO LINE. KPDX AND APPROACHES...VFR TODAY BUT CIGS LOWER TO 5000 FT 14Z TO 16Z. CIGS LOWER FURTHER LATE TODAY...WITH MVFR BECOMING MORE DOMINANT BETWEEN 02Z AND 06Z. MAIN IMPACT WILL BE GUSTY E WINDS AFTER 18Z...WITH PEAK GUSTS 30 TO 35 KT.ROCKEY. && .MARINE...CONDITIONS WILL REMAIN FAIRLY BENIGN ACROSS THE COASTAL WATERS TODAY INTO EARLY SUN. LIGHT TO MODERATE OFFSHORE FLOW MAY BECOME GUSTY AT TIMES BY LATE AM...WITH A FEW GUSTS UP TO 25 KT POSSIBLE...MAINLY BELOW THE COASTAL GAPS AND THROUGH THE COLUMBIA RIVER. A MORE ACTIVE WEATHER PATTERN LOOKS TO BEGIN LATER SUN/MON. A WARM FRONT WILL LIFT N ACROSS THE COASTAL WATERS SUN NIGHT INTO MON AM. A STRONG FRONT WILL ARRIVE TUE NIGHT...WITH INCREASING POTENTIAL OF SOUTHERLY GALES AT THAT TIME. REST OF WEEK WILL REMAIN BREEZY AND UNSETTLED AS MORE FRONTS ARRIVE. ROCKEY. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...WIND ADVISORY FROM 6 AM THIS MORNING TO 6 AM PST SUNDAY FOR GREATER PORTLAND METRO AREA. WINTER WEATHER ADVISORY FROM 6 PM TONIGHT TO 6 AM PST SUNDAY FOR CENTRAL COLUMBIA RIVER GORGE-UPPER HOOD RIVER VALLEY- WESTERN COLUMBIA RIVER GORGE. WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY MORNING FOR CENTRAL COLUMBIA RIVER GORGE-UPPER HOOD RIVER VALLEY- WESTERN COLUMBIA RIVER GORGE. WA...WIND ADVISORY FROM 6 AM THIS MORNING TO 6 AM PST SUNDAY FOR GREATER VANCOUVER AREA. WINTER WEATHER ADVISORY FROM 6 PM TONIGHT TO 6 AM PST SUNDAY FOR CENTRAL COLUMBIA RIVER GORGE-WESTERN COLUMBIA RIVER GORGE- SOUTH WASHINGTON CASCADES. WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY MORNING FOR CENTRAL COLUMBIA RIVER GORGE-WESTERN COLUMBIA RIVER GORGE-SOUTH WASHINGTON CASCADES. PZ...NONE. && $$ MORE WEATHER INFORMATION ONLINE AT.. HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV 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.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
337 AM PST SAT MAR 1 2014 .SYNOPSIS...STRONG LOW PRESSURE IS DRIFTING INTO SOUTHERN CALIFORNIA THIS MORNING. LEFTOVER MOISTURE FROM AN ASSOCIATED FRONT CONTINUES TO BRING RAIN AND HIGH ELEVATION SNOW TO PORTIONS OF LANE AND LINN COUNTIES. OTHERWISE THE BIG STORY TODAY WILL BE A STRONG PUSH OF COLD AIR COMING DOWN FROM THE CANADIAN ROCKIES. A BACKDOOR COLD FRONT HAS PUSHED SOUTHWEST ACROSS THE COLUMBIA BASIN...AND HAS ARRIVED ALONG THE EAST SLOPES OF THE CASCADES. THIS FRONT WILL PUSH WESTWARD THROUGH THE GORGE AND ACROSS THE PORTLAND METRO AREA TODAY WITH COLD EAST WINDS TO FOLLOW LATER TODAY THROUGH SUNDAY. WHILE IT DOES NOT APPEAR IT WILL BE COLD ENOUGH FOR WINTRY PRECIP IN THE PORTLAND METRO AREA...THERE IS A THREAT FOR SIGNIFICANT SNOW AND ICE IN THE GORGE AND HOOD RIVER VALLEY TONIGHT UNTIL THE COLD AIR SCOURS OUT SUNDAY NIGHT OR MONDAY. OTHERWISE...A SERIES OF PACIFIC STORM SYSTEMS WILL BRING PERIODS OF RAIN...MOUNTAIN SNOW...AND COASTAL WIND FOR MUCH OF THE UPCOMING WEEK. && .SHORT TERM...TODAY THROUGH MONDAY...LET ME START OFF BY SAYING THIS IS ONE OF THE MOST CHALLENGING FORECASTS THUS FAR IN MY CAREER...AS IT IS A VERY ODD PATTERN WHERE A MAJOR SURGE OF COLD AIR MAY OR MAY NOT BE SUCCESSFUL PUSHING ALL THE WAY SOUTHWEST FROM THE CANADIAN PRAIRIE PROVINCES ACROSS BOTH THE ROCKIES AND CASCADES. THIS IS VERY TOUGH FOR COLD AIR TO DO SUCCESSFULLY...BUT IT IS POSSIBLE AND MOST MODELS HAVE BEEN FAIRLY CONSISTENT IN SUGGESTING IT WILL. SOME MODELS SUCH AS THE NAM STILL SUGGEST THERE COULD BE WINTRY PRECIPITATION IN THE PORTLAND METRO AREA LATER TODAY INTO EARLY SUNDAY...WHILE OTHERS SUCH AS THE RAP ARE NOT EVEN BRINGING ENOUGH COLD AIR TO CREATE A SIGNIFICANT SNOW/ICE EVENT IN THE GORGE OR HOOD RIVER VALLEY. TO GIVE AN EXAMPLE OF THE UNCERTAINTY HERE...THE 06Z NAM BUFR SOUNDING SUGGESTED TEMPS WILL BE IN THE LOW 20S IN HOOD RIVER AT 3 PM THIS AFTERNOON. MEANWHILE THE 06Z RAP SUGGESTS TEMPS WILL BE IN THE UPPER 40S AT THE SAME PLACE AT THE SAME TIME. I BELIEVE BOTH ARE WRONG...STICKING TO THE TYPICAL BIASES OF THE NAM BEING TOO COLD AND THE RAP BEING TOO WARM. THE REALITY WILL MOST LIKELY SOMEWHERE IN BETWEEN THESE EXTREMES. NEEDLESS TO SAY CONFIDENCE IN ANY DETERMINISTIC FORECAST IS UNUSUALLY LOW IN THIS SITUATION...BUT WE WILL DO OUR BEST. LETS START WITH THE TWO MODELS I MENTIONED EARLIER...THE NAM AND THE RAP. THE COLD AIR IS ALREADY WELL BEHIND THE 00Z NAM FORECAST AND EVEN THE 06Z INITIALIZATION. CHECKING SFC PRESSURES...THE 09Z NAM FORECAST FOR CENTRAL WA ARE ALREADY 4-6 MB TOO HIGH. TEMPS REMAIN ABOVE FREEZING FOR ALL BUT THE EASTERN THIRD OF WASHINGTON...EXCEPT MOSES LAKE AND EPHRATA. THE 06Z NAM BUFR SOUNDING FOR KDLS SAID IT WOULD BE 28 DEG F BY NOW...THE 11Z OB FOR KDLS SAYS IT IS STILL 42. THIS MARKS LITTLE CHANGE FROM WHERE THE TEMP HAS BEEN SITTING AT KDLS MUCH OF THE NIGHT. HOWEVER THE COLD ADVECTION HAS JUST STARTED... EAST WINDS AT 10 KT HAVE PICKED UP AND THE DEWPOINT FELL 7 DEG F IN ONE HOUR. SO IT IS SAFE TO SAY OUR BACKDOOR COLD FRONT HAS PUSHED W-SW INTO THE COLUMBIA GORGE...BUT IS DOING SO MUCH SLOWER AND WITH MUCH LESS BLUSTER THAN THE NAM SUGGESTED. MEANWHILE THE RAP HAS BEEN DOING MUCH BETTER WITH THE HANDLING OF THE COLD AIR...BEING MUCH SLOWER AS IT HAS THE BENEFIT OF BEING REINITIALIZED EACH HOUR. WHERE THE RAP LIKELY GOES WRONG IS WHAT IT DOES WITH THE COLD AIR LATER TODAY. STRANGELY...THE RAP HAS THE EASTSIDE COLD POOL ESSENTIALLY SURRENDERING LATER TODAY DUE TO INCREASING WESTERLY FLOW ALOFT AND SUPPOSED WARM ADVECTION IN BRITISH COLUMBIA ASSOCIATED WITH A DISTURBANCE SLIDING DOWN THE COAST. THIS DISTURBANCE APPEARS FAR TOO WEAK TO DEFEAT A FULL-ON PUSH OF ARCTIC AIR...AND THE RAP IS OUT ON ITS OWN WITH THIS IDEA. SUSPECT THE EASTSIDE COLD POOL WILL CONTINUE TO STRENGTHEN OVER THE NEXT 12-24 HRS AS THE NAM/GFS/UKMET/ ECMWF/GEM ALL INDICATE TO SOME DEGREE. THE 00Z/06Z GFS ALSO HAS DONE MUCH BETTER WITH ITS INITIALIZATION... BOTH WITH SFC PRESSURES AND THE MAGNITUDE/PROGRESS OF THE COLD AIR. IT ALSO SEEMS TO BE HANDLING THE STRONG LOW OFF CALIFORNIA AND ACTIVITY FURTHER OUT INTO THE PACIFIC FAIRLY WELL. THEREFORE THE LATEST RUNS OF THE GFS ARE PREFERRED...AND ESSENTIALLY OUR FORECAST IS A BLEND BETWEEN THE PREVIOUS FORECAST AND THE GFS/WRFGFS. WE DECIDED TO PUSH BACK THE START OF THE WINTER WX ADVISORY IN THE GORGE TO 6 PM FOR SEVERAL REASONS. FIRST...THE DELAY IN ARRIVAL OF COLD AIR. SECOND...THE UNCERTAINTY IN THE AMOUNT OF QPF EXPECTED TODAY. AND THIRD...THE EARLY MARCH SUN AND ITS IMPACT ON SURFACE TEMPS. TEMPS HAVE GENERALLY BEEN IN THE 40S ALL NIGHT...SO SURFACES TAKE SOME TIME TO COOL OFF ENOUGH TO ALLOW ICE ACCRETION. THE STRONGER EARLY MARCH SUN WILL BE FIGHTING THE COLD AIR...EVEN THOUGH IT WILL LIKELY BE CLOUDY THROUGHOUT THE DAY THERE WILL LIKELY BE ENOUGH SOLAR ENERGY TO KEEP MOST SURFACES ABOVE FREEZING THROUGHOUT THE DAY. OUTSIDE OF THE GORGE...TODAY WILL SEE RAIN GRADUALLY INCREASING ACROSS THE AREA DUE TO LOW AND MID-LEVEL FRONTOGENESIS ASSOCIATED WITH THE BACKDOOR COLD FRONT MEETING THE MILD AND MOIST AIR MASS IN PLACE. AS COLD HIGH PRESSURE BUILDS EAST OF THE CASCADES...EASTERLY PRES GRADIENTS AND THUS EAST WINDS WILL INCREASE THROUGH THE GORGE. THIS SHOULD CAUSE TEMPS TO STAY STEADY OR SLOWLY FALL THROUGH THE DAY IN THE PDX METRO AREA...WHILE AREAS OUTSIDE OF THE GORGE OUTFLOW ONCE AGAIN AIM FOR THE 50S. IT APPEARS VERY QUESTIONABLE WINDS WILL BE STRONG ENOUGH FOR AN ADVISORY...BUT THERE IS ENOUGH UNCERTAINTY IN THIS SITUATION TO KEEP THE EXISTING WIND ADVISORY IN PLACE FOR THE EAST PORTLAND METRO. NORTHEAST WINDS ASSOCIATED WITH THE COLD ADVECTION ARE RATHER STRONG IN THE COLUMBIA BASIN...IT WILL BE INTERESTING TO SEE WHAT THEY DO THIS MORNING WHEN THEY REACH THE CASCADES. THE COLD POOL WILL LIKELY BE DEEP ENOUGH TO SUPPORT A WINDY DAY FOR MUCH OF THE METRO...RATHER THAN CONFINE STRONGER WINDS TO THE GORGE. EXPECT MANY SPOTS IN AND AROUND PORTLAND/VANCOUVER WILL SEE GUSTS IN THE 30-40 MPH RANGE...WITH PERHAPS AN ISOLATED 45 MPH GUST OR TWO. THE RESULTING DOWNSLOPING OF THE BROADER EAST WIND MAY ALSO TAKE A BIT OF THE EDGE OFF THE MAGNITUDE OF THE COLD AIR TRYING TO SPILL WEST OF THE CASCADES. AS A RESULT WE BUMPED TEMPS UP SLIGHTLY TODAY...AND LEFT ONLY A SLIGHT CHANCE OF FZRA AROUND TROUTDALE TONIGHT. KEEP IN MIND THE NAM BUFR SOUNDINGS CONTINUE TO SUGGEST A HIGH IMPACT ICE EVENT THROUGHOUT THE METRO THIS AFTERNOON THROUGH SUNDAY MORNING...BUT AGAIN THE NAM HAS BEEN DISCOUNTED DUE TO THE FACT IT IS FAR TOO FAST AND STRONG WITH THE EASTSIDE COLD AIR. A PACIFIC DISTURBANCE WILL BEGIN TO SPREAD MORE RAIN ACROSS THE DISTRICT SUNDAY. AS THE LOW PRESSURE SYSTEM APPROACHES...THERE MAY BE A BIT OF A COASTAL JET WHICH WOULD ALLOW BRIEF WINDS GUSTING 40-50 MPH ALONG THE BEACHES AND HEADLANDS. ANOTHER SIMILAR SYSTEM IS EXPECTED FOR MONDAY...AND THESE SYSTEMS WILL HAVE AN INCREASING TAP OF SUBTROPICAL MOISTURE. THIS MOISTURE WILL BE OVERRUNNING THE COLD AIR IN THE GORGE AND HOOD RIVER VALLEY... POSSIBLY RESULTING IN SUBSTANTIAL SNOW AND ICE ACCUMULATIONS BEFORE THE COLD AIR FINALLY SCOURS OUT MONDAY. AT THIS MOMENT OUR HUNCH IS THAT TEMPS WILL MODERATE JUST ENOUGH SUNDAY TO ALLOW THE SECOND SURGE OF MOISTURE TO FALL AS PLAIN RAIN IN THE GORGE AND NEAR HOOD RIVER. AGAIN...LEFT THE EXISTING WINTER STORM WATCH IN PLACE DUE TO THE UNCERTAINTY... BUT IT APPEARS THE BEST CHANCE FOR WINTRY PRECIP SUN NIGHT/MON WILL BE IN UPPER PORTIONS OF THE HOOD RIVER VALLEY AND POSSIBLY EASTERN SKAMANIA COUNTY. TEMPS WARM WELL INTO THE 50S ON GUSTY SOUTH WINDS THROUGH THE WILLAMETTE VALLEY MONDAY...POSSIBLY INTO THE 40S AND LOWER 50S IN THE GORGE BY MONDAY AFTERNOON OR EVENING. AN ACTIVE PACIFIC STORM TRACK WILL KEEP THINGS WET WELL INTO THE UPCOMING WEEK...BUT TEMPS WILL WARM UP JUST ENOUGH TO GIVE MANY OF US A HINT OF SPRING TO THE AIR BY MIDWEEK. WEAGLE .LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS... MONDAY NIGHT THROUGH FRIDAY...MILD BUT WET CONDITIONS ARE EXPECTED NEXT WEEK AS STRONG WESTERLY FLOW PREVAILS. A MOIST PACIFIC FRONTAL SYSTEM WILL MOVE ONSHORE LATE MONDAY...LIFTING SNOW LEVELS ABOVE PASS LEVEL. STRONG OROGRAPHIC LIFT WILL ALLOW ABUNDANT PRECIPITATION OVER THE CASCADES AND COAST RANGE MONDAY NIGHT INTO TUESDAY. BOTH THE 12Z GFS AND ECMWF ARE STILL IN GOOD AGREEMENT SHOWING BACK TO BACK SYSTEMS MOVING THROUGH WEDNESDAY AND THURSDAY. THEY BOTH SETUP AN UPPER LOW IN THE GULF OF ALASKA AND ANOTHER JUST OFF THE OREGON/CALIFORNIA BORDER. THE 12Z ECMWF HAS A 985 MB SURFACE LOW DEVELOPING LATE WEDNESDAY NIGHT AND HAS IT SETUP A LITTLE FURTHER SOUTH OF THE GFS SOLUTION. MAY SEE SOME DECENT COASTAL WINDS WITH THIS SETUP AS THE LOW LIFTS NORTH ALONG THE COAST THROUGH THURSDAY MORNING. POST FRONTAL SHOWERS CONTINUE INTO LATE NEXT WEEK AS MODELS SUGGEST AN AMPLIFYING TROUGH OVER THE PACIFIC NORTHWEST. /27 && .AVIATION...VFR ACROSS REGION THIS AM. HOWEVER...OCCASIONAL LIGHT RAIN WITH CIGS MVFR AND LOCALLY IFR S BETWEEN KS12 AND K61S...MOSTLY AFFECTING KEUG. NOT MUCH CHANGE TODAY WITH MOSTLY VFR ALONG THE COAST AND INLAND N OF KSLE. THAT SAID...CIGS WILL GRADUALLY LOWER ACROSS INLAND NW OREGON TODAY AS MORE MOISTURE ALOFT ARRIVES FROM THE S. OFFSHORE FLOW WILL GRADUALLY INCREASE TODAY OVER W WASHINGTON AND NW OREGON TODAY...WITH BREEZY WINDS FOR AREAS N OF A KTMK TO KUAO LINE. KPDX AND APPROACHES...VFR TODAY BUT CIGS LOWER TO 5000 FT 18Z TO 20Z. CIGS LOWER FURTHER LATE TODAY...WITH MVFR BECOMING MORE DOMINANT BETWEEN 02Z AND 06Z. MAIN IMPACT WILL BE GUSTY E WINDS AFTER 18Z...WITH PEAK GUSTS 30 TO 35 KT.ROCKEY. && .MARINE...CONDITIONS WILL REMAIN FAIRLY BENIGN ACROSS THE COASTAL WATERS TODAY INTO EARLY SUN. LIGHT TO MODERATE OFFSHORE FLOW MAY BECOME GUSTY AT TIMES BY LATE AM...WITH A FEW GUSTS UP TO 25 KT POSSIBLE...MAINLY BELOW THE COASTAL GAPS AND THROUGH THE COLUMBIA RIVER. A MORE ACTIVE WEATHER PATTERN LOOKS TO BEGIN LATER SUN/MON. A WARM FRONT WILL LIFT N ACROSS THE COASTAL WATERS SUN NIGHT INTO MON AM. A STRONG FRONT WILL ARRIVE TUE NIGHT...WITH INCREASING POTENTIAL OF SOUTHERLY GALES AT THAT TIME. REST OF WEEK WILL REMAIN BREEZY AND UNSETTLED AS MORE FRONTS ARRIVE. ROCKEY. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...WIND ADVISORY FROM 6 AM THIS MORNING TO 6 AM PST SUNDAY FOR GREATER PORTLAND METRO AREA. WINTER WEATHER ADVISORY FROM 6 PM TONIGHT TO 6 AM PST SUNDAY FOR CENTRAL COLUMBIA RIVER GORGE-UPPER HOOD RIVER VALLEY- WESTERN COLUMBIA RIVER GORGE. WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY MORNING FOR CENTRAL COLUMBIA RIVER GORGE-UPPER HOOD RIVER VALLEY- WESTERN COLUMBIA RIVER GORGE. WA...WIND ADVISORY FROM 6 AM THIS MORNING TO 6 AM PST SUNDAY FOR GREATER VANCOUVER AREA. WINTER WEATHER ADVISORY FROM 6 PM TONIGHT TO 6 AM PST SUNDAY FOR CENTRAL COLUMBIA RIVER GORGE-WESTERN COLUMBIA RIVER GORGE- SOUTH WASHINGTON CASCADES. WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY MORNING FOR CENTRAL COLUMBIA RIVER GORGE-WESTERN COLUMBIA RIVER GORGE-SOUTH WASHINGTON CASCADES. PZ...NONE. && $$ MORE WEATHER INFORMATION ONLINE AT.. HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV 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.
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
313 PM EST SAT MAR 1 2014 .SYNOPSIS... DRY HIGH PRESSURE WILL LINGER OVER THE AREA THROUGH THE WEEKEND BEFORE A MOIST COLD FRONT APPROACHES FROM THE WEST ON MONDAY. ANOTHER AREA OF HIGH PRESSURE WILL BUILD DOWN THE EAST COAST TUESDAY WITH A SOUTHEASTERN COASTAL LOW DEVELOPING ON THURSDAY. && .NEAR TERM /THROUGH SUNDAY/... AS OF 230 PM...THERE WILL BE A FLAT UPR RIDGE ACRS THE SOUTHEAST STATES THRU THE NEAR TERM...WHILE A POTENT SHORTWAVE TROF BEGINS TO ENTER THE SRN PLAINS. SFC HIGH PRES WILL LINGER JUST OFF THE SOUTH ATLANTIC COAST...ALLOWING FOR INCREASING SWLY LLVL RETURN FLOW ATOP THE CWFA TONIGHT THRU SUNDAY. FCST SNDGS INDICATE DECENT RADIATIONAL COOLING WITH INCREASING BL MOISTURE WITHIN THE SW FLOW. AS A RESULT...THERE WILL BE SOME POTENTIAL FOR FOG DEVELOPMENT EARLY SUNDAY MORNING. THE NAM IN PARTICULAR HINTS AT SOME FOG OR LOW STRATUS DEVELOPMENT...PRIMARILY ACRS THE PIEDMONT. MOST OF THE OTHER GUIDANCE DOES NOT SHOW THIS...EXCEPT PERHAPS THE RAP HINTING AS WELL. WILL KEEP A MENTION OF PATCHY FOG TONIGHT...HIGHLIGHTING THE AREA WHERE THE NAM AS NEAR ZERO SFC CONDENSATION PRES DEFICITS. HOWEVER...CONFIDENCE ON DENSE FOG IS STILL LOW. TEMPS WILL BE KEPT ABOVE NORMAL WITHIN THE RETURN FLOW REGIME OVERNIGHT. SUNDAY...GUIDANCE IN GOOD AGREEMENT ON A COLD FRONT SAGGING SEWD ACRS THE OH VLY...BUT PRECIP HOLDING OFF TO THE NORTH BEHIND THE SFC BNDRY. SO WE WILL SEE AN INCREASE IN MAINLY THICKENING HIGH CLOUDS DURING THE AFTN...BUT OTHERWISE IT SHUD BE A VERY NICE DAY WITH HIGHS ABOUT 8-10 DEG ABOVE NORMAL. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... AS OF 230 PM EST SAT...AN APPROACHING UPPER LEVEL SHORTWAVE WILL DEAMPLIFY AS IT MOVES SWIFTLY EWD FROM THE PLAINS TO THE SRN APPALACHIANS SUN NIGHT THROUGH MON MORNING. THE WAVE WILL INTERACT WITH A LOW LEVEL FRONTAL ZONE DRAPED ALONG THE OH AND MID MS RIVER VALLEYS AND GENERATE SFC WAVES ALONG THE BOUNDARY. MOST OF THE MOISTURE WITH THE BOUNDARY WILL BE CONFINED TO THE IMMEDIATE FRONTAL ZONE AND THE COLD SIDE...KEEPING OUR AREA IN THE WARM SECTOR THROUGH SUN NIGHT...WITH ONLY SLOWLY BUILDING POPS AS THE FRONT BEGINS TO GET SHUTTLED EWD. FORCING FEATURES COME TOGETHER BEST ACROSS THE AREA MON MORNING IN THE FORM OF RIGHT ENTRANCE REGION UPPER JET DIVERGENCE...PASSING DEEP LAYER Q VECTOR CONVERGENCE WITH THE SHORTWAVE...LOW LEVEL CONVERGENCE AS THE SFC WAVE SWEEPS IN ALONG THE FRONTAL ZONE...AND POSSIBLY WEAK DEFORMATION ZONE FORCING THROUGH LATE DAY NW OF THE SFC WAVE AFTER THE BOUNDARY SLIPS THROUGH THE AREA. THIS WILL WARRANT LIKELY TO CAT POPS THROUGHOUT MON MORNING. EVEN WITH THE SFC WAVE DEVELOPMENT...MUCAPES WILL BE LIKELY BE LIMITED TO 100 J/KG OR LESS...WITH 850 TO 500 MB LAPSE RATES 5.5 TO 6 DEG C/KM...AND WITH WESTERLY SHEAR PROFILES. THIS WILL GREATLY LIMIT THE TSTM POTENTIAL AND ONLY SHOWERS WILL BE MENTIONED IN THE WARM SECTOR. COLD AIR WILL RAPIDLY SURGE INTO THE NRN TIER MON AFTERNOON AS THE COLD FRONT MOVES THROUGH FROM THE W AND A BACKDOOR FRONT WRAPS DOWN FROM THE N. THE RACE WILL THEN BE ON BETWEEN THE MOISTURE EXITING SE AND COLDER PROFILES ARRIVING FROM THE N TO SUPPORT A WINTRY MIX. STILL FEEL THAT ANY ACCUMULATING WINTRY PRECIP WOULD BE CLIMATOLOGICALLY UNFAVORED IN THIS SETUP. IN ADDITION... PROFILES APPEAR TO DRY OUT FROM THE TOP DOWN IN THE COLDER NRN TIER...LIKELY ENDING THE POTENTIAL FOR ICE NUCLEATION AND ANY ACCUMULATING FREEZING/FROZEN PRECIPITATION. BRIEF PATCHY FREEZING DRIZZLE OR VERY LIGHT FREEZING RAIN COULD STILL OCCUR OVER THE NW NC PIEDMONT LATE MON...WITH BRIEF FREEZING DRIZZLE OR LIGHT SNOW SHOWERS LINGERING IN THE MTNS NEAR THE NC BORDER INTO EARLY EVENING. NO HAZARD HEADLINES ARE EXPECTED AT THIS TIME. H5 FLOW WILL QUICKLY BECOME ZONAL THROUGH TUE...WITH 1032 MB HIGH PRES BUILDING OVER TO THE N FROM THE OH VALLEY TO THE MID ATLANTIC REGION. THIS...ALONG WITH SOME PATCHY HIGH CLOUDS...MAY CAP TUE MAX TEMPS AT 10 TO 15 DEGREES BELOW CLIMO. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 310 PM SATURDAY...TRICKY MEDIUM RANGE FCST CONTINUES AS GENERAL OVERALL AGREEMENT EXISTS...BUT SIGNIFICANT DETAIL DIFFERENCES REMAIN AS WELL. THE ECMWF HAS BEEN THE MOST CONSISTENT SHOWING A STRONG SHORT WAVE DIVING TO THE WRN GULF COAST BY WED NITE THEN CUTTING OFF AN UPPER LOW ON THU. THIS LOW THEN MOVES EAST ALONG THE GULF COAST THU NITE AND UP THE EASTERN SEABOARD FRI AND SAT. THE CANADIAN MODEL IS COMING AROUND TOWARD THIS SOLUTION WITH SOME MINOR PLACEMENT AND TIMING DIFFERENCES. THE GFS REMAINS THE OUTLIER WITH A MUCH FASTER AND OPEN WAVE. THE GFS HAS NOT BEEN AS CONSISTENT WITH THE STRENGTH...POSITION OR TIMING OF THIS SYSTEM. THE GEFS ENSEMBLE MEAN IS DEEPER AND SLOWER WITH THIS SYSTEM...BUT NOT AS DEEP OR SLOW AS THE ECMWF OR CANADIAN. WPC IS TRENDING TOWARD THE DEEPER AND SLOWER SCENARIO...SO HAVE GONE THIS DIRECTION AS WELL. WED WILL BE A COOL DRY DAY WITH TEMPS 5 TO 10 DEGREES BELOW NORMAL AS HIGH PRESSURE NOSES INTO THE AREA FROM THE NORTH IN A CLASSICAL CAD PATTERN. THE GULF LOW SPINS UP ON THU AND MOVES EAST SPREADING MOISTURE AND PRECIP INTO THE AREA OVER THE DEVELOPING CAD. THE GFS WITH ITS WEAKER AND FASTER LOW...KEEPS THE BULK OF THE PRECIP GENERALLY SOUTH OF I-85. HOWEVER...THE ECMWF AND CANADIAN ARE WETTER. THEREFORE...SPREAD CHC POP IN ACROSS THE SRN CWFA WED NITE AND THE ENTIRE CWFA THU. PARTIAL THICKNESSES...H85 TEMPS...AND SFC TEMPS SUGGEST SNOW AND SLEET WOULD DEVELOP ALONG AND NORTH OF I-85 AS THE PRECIP MOVES IN WED NITE...WITH SOME FREEZING RAIN SOUTH. AS TEMPS WARM THRU THE DAY THU...PRECIP CHANGES TO RAIN IN ALL BUT THE DEEPEST PART OF THE CAD DOME...NEAR AND ALONG THE BLUE RIDGE. AS THE LOW MOVES UP THE SERN COAST THU NITE AND FRI...PRECIP REMAINS ACROSS THE CWFA. PARTIAL THICKNESSES AND TEMPS REMAIN COOL OVER THE MTNS WITH SFC TEMPS FALLING ALONG THE I-40 CORRIDOR TOWARD DAYBREAK. A STRONG WARM NOSE DEVELOPS WITH CONTINUING WWA. THIS CHANGES ANY WINTRY PRECIP IN THOSE COLDER AREAS TO FREEZING RAIN. PRECIP TAPERS OFF ACROSS THE WRN CWFA FRI AFTERNOON AND ALL AREAS FRI EVENING AS THE LOW PULLS AWAY FROM THE AREA TAKING MOISTURE AND FORCING WITH IT. PRECIP WILL CHANGE TO ALL RAIN FRI AS THE WWA CONTINUES AND REMAINS RAIN UNTIL ENDING. RIGHT NOW...THERE IS MUCH UNCERTAINTY REGARDING THE THICKNESS AND TEMP PATTERN...EVEN THOUGH THERE IS A LITTLE BETTER CONFIDENCE THAT A PRECIP EVENT WITH A STRONG UPPER LOW AND SFC GULF LOW WILL DEVELOP. FOR NOW...HAVE GONE FOR SNOW/SLEET LESS THAN AN INCH ALONG AND NORTH OF I-85...WITH UP TO 2 INCHES OVER THE NRN MTNS. ALSO HAVE TRACE ICE ACCRETION NORTH OF I-85 AND LESS THAN A QUARTER INCH OVER THE MTNS...WITH HIGHEST AMOUNTS OVER THE NRN MTNS. AGAIN...THIS IS VERY UNCERTAIN...SO STAY TUNED. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... AT KCLT...VFR CONDITIONS ARE EXPECTED THRU THE PERIOD. THE 18Z TAF STARTING OUT WITH BKN-OVC MID CLOUDS...WHICH SHUD CLEAR OUT WITHIN THE NEXT COUPLE HOURS...LEAVING MAINLY JUST FEW-SCT CIRRUS FOR THIS EVENING THRU THE OVERNIGHT. HIGH PRES WILL SHIFT EAST OFF THE COAST...ALLOWING FOR WINDS TO VEER FROM SE TO SW AND ADVECT HIGHER DEWPTS INTO THE AREA. THE NAM AND RAP GUIDANCE HINT AT SOME FOG/LOW STRATUS POTENTIAL AROUND DAYBREAK SUNDAY. HOWEVER...NONE OF THE OTHER GUIDANCE IS EVEN PICKING UP ON THIS AT ALL. SO CONFIDENCE IS TOO LOW TO MENTION IN THE TAF FOR NOW. SW WINDS WILL INCREASE TO THE 5-8 KT RANGE AROUND MIDDAY SUNDAY...WITH SOME INCREASING CIRRUS STREAMING IN FROM THE WEST. ELSEWHERE...VFR EXPECTED THRU THE PERIOD...EXCEPT FOR A SMALL POTENTIAL FOR PATCHY FOG DEVELOPMENT AROUND DAYBREAK SUNDAY...ESP IN THE MTN VLYS. MID CLOUDS WILL CLEAR OUT FOR THE MOST PART...AND HIGH PRES WILL SHIFT EAST ALLOWING RETURN FLOW TO BRING INCREASING MOISTURE FROM THE SOUTH. CONFIDENCE IS TOO LOW TO MENTION IN ANY OF THE PIEDMONT TAFS FOR NOW. WINDS WILL BE LIGHT...GENERALLY OUT OF THE S/SW. OUTLOOK...QUIET SUNDAY. A FRONT WILL BRING WIDESPREAD SHOWERS AND SOME RESTRICTIONS MONDAY. DRY HIGH PRESSURE TUESDAY AND WEDNESDAY. CONFIDENCE TABLE... 20-02Z 02-08Z 08-14Z 14-20Z KCLT HIGH 100% HIGH 100% HIGH 90% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 94% HIGH 100% KAVL HIGH 100% HIGH 100% MED 77% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 94% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 97% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...ARK SHORT TERM...HG LONG TERM...RWH AVIATION...ARK
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
629 AM CST SAT MAR 1 2014 .UPDATE...TO CORRECT GRAMMAR IN FIRST LINE && .AVIATION...12Z AVIATION FORECAST && .PREV DISCUSSION... /ISSUED 618 AM CST SAT MAR 1 2014/ UPDATE...FOR 12Z AVIATION FORECAST AVIATION... ..POOR FLYING WEATHER SUNDAY NIGHT INTO MONDAY IN MIDDLE TENNESSEE... SHORT WAVE THAT BROUGHT RAIN OVERNIGHT HAS PUSHED OFF TO THE EAST AND CAN BE SEEN IN THE LATEST WATER VAPOR LOOP OVER EASTERN GEORGIA INTO THE CAROLINAS. SOUTHERN BRANCH OF THE POLAR JET WILL PUSH NORTHWARD TODAY FROM GULF. THIS IS ALREADY TAKING PLACE AS CAN BE SEEN BY HEIGHT FIELDS FROM GULF REGION LIFTING NORTHWARD IN LATEST RUC LOOP. THINK STRATOCU WILL REMAIN ACROSS THE AREA NEXT 24 HOURS WITH A LOWERING IN THE CEILING AFTER 00Z THIS EVENING POSSIBLY INTO THE IFR RANGE LATE TONIGHT. IN THE LATEST CONUS WATER VAPOR LOOP ONE CAN SEE A STRONG TWIST IN THE IMAGERY NEARING THE CALIFORNIA COAST. THIS WILL BE THE NEXT WEATHER MAKER THAT PILOTS WILL HAVE TO CONTEND WITH. BY SUNDAY THIS SYSTEM WILL DEVELOP A STRONG BAROCLINIC ZONE FROM TEXAS NORTHEASTWARD THROUGH THE OHIO VALLEY AND EVENTUALLY INTO THE NORTHEAST. WINTRY PRECIP IN THE FORM OF FREEZING RAIN AND SLEET BEGINNING TO LOOK LIKELY ACROSS THE NORTHWEST HALF OF MIDDLE TENNESSEE SUNDAY NIGHT INTO EARLY MONDAY. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ BOYD 01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1134 PM CST FRI FEB 28 2014 .UPDATE...FOR 06Z AVIATION && .AVIATION... A MIX OF VERY LIGHT RAIN/SLEET WILL CONTINUE TO MOVE ACROSS MIDDLE TN WITH VFR CIGS FOR THE NEXT FEW HOURS. MVFR CIGS TRAIL THE UPPER DISTURBANCE MOVING OVERHEAD...SO WILL KEEP THAT IN THE AREA TERMINALS FOR EARLY SATURDAY. AN APPROACHING WARM FRONT WILL PUSH ACROSS THE STATE SAT AFTN...VEERING WINDS AROUND TO THE SSW AND SCATTERING OUT THE CLOUDS. WINDS MAY BECOME GUSTY TOWARDS THE END OF THIS TAF PERIOD. && .PREV DISCUSSION... /ISSUED 747 PM CST FRI FEB 28 2014/ UPDATE...RECENTLY RECEIVED SOME REPORTS OF SLEET FROM OUR SOUTHERN COUNTIES AND RUC SOUNDINGS INDICATE THAT SLEET WILL REMAIN A POSSIBILITY ALONG THE LEADING EDGE OF THE PRECIP BAND AS IT TRAVERSES OUR AREA TONIGHT. LOOKS LIKE TEMPS AND DEW POINTS WARM SUFFICIENTLY ALONG THE LAGGING PART OF THE BAND, SO THAT PRECIP WILL LIKELY CHANGE BACK TO ALL RAIN BEFORE ENDING. THUS, HAVE ADDED A BRIEF PERIOD FOR THE POSSIBILITY OF SLEET INTO THE OVERNIGHT FORECAST. OTHERWISE, NO CHANGE. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ AL
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
935 PM CST SUN MAR 2 2014 .DISCUSSION...THE STRONG COLD FRONT HAS PUSHED THROUGH THE CWA THIS EVENING RESULTING IN STRONG GUSTY N WINDS AND FALLING TEMPS. BASED ON THE LATEST TEMP TRENDS AND HOW FAST THEY ARE FALLING AND DUE TO SEVERAL MODELS PROGING FREEZING TEMPS ACROSS THE NRN PORTIONS OF THE CWA...HAVE FOLLOWED SUIT AND LOWERED MN TEMPS BY A FEW DEGREES RESULTING IN A LIGHT FREEZE ACROSS THE NRN CWA AND MORE WIDESPREAD WIND CHILL VALUES BELOW 25 DEGREES. THEREFORE HAVE EXPANDED THE WIND CHILL ADVISORY TO INCLUDE ALL OF THE CWA INCLUDING THE EASTERN PORTIONS OF WEBB AND LA SALLE COUNTIES. ALSO ISSUING A SPECIAL WEATHER STATEMENT TO ADDRESS THE BRIEF LIGHT FREEZING TEMPS. && .PREV DISCUSSION... /ISSUED 659 PM CST SUN MAR 2 2014/ DISCUSSION...STRONG COLD FRONT IS MOVING THROUGH THE CWA A LITTLE FASTER BY A COUPLE OF HOURS THAN PREVIOUSLY ANTCIPATED. HAVE UPDATED FCST TO ACCOUNT FOR THE FASTER FROPA AND WENT EARLIER WITH THE SMALL CRAFT ADVISORY FOR THE BAYS. WINDS BEHIND THE FROPA HAVE BEEN INITIALLY GUSTING BETWEEN 30-40 KNOTS THEN DECREASING TO 28-35KTS...THEREFORE AM NOT ANTCIPATING WIND ADVISORY CONDITIONS AT THIS TIME. HOWEVER...WIND CHILL ADVISORY FOR THE VICTORIA CROSSROADS REMAINS IN EFFECT. ISOLD SHRA`S HAVE ALSO BEEN DVLPG ALONG AND BEHIND THE FRONT...BUT IS EXPECTED TO DIMINISH OVERNIGHT FROM NW TO SE. SOME MODELS PROG MN TEMPS OF 31 DEGREES AROUND VCT BUT THINK CLOUD COVER AND STRONG WINDS WILL KEEP MN TEMPS JUST ABV FREEZING BUT A BRIEF DIP TO 32 DEGREES AROUND SUNRISE ACROSS A FEW LOCATIONS ACROSS THE NRN CWA IS NOT OUT OF THE QUESTION. ONLY MADE TWEAKS TO TEMPS/DEWPOINTS/WSHFT TO ACCOUNT FOR THE FASTER FROPA. PREV DISCUSSION... /ISSUED 548 PM CST SUN MAR 2 2014/ DISCUSSION...SEE 00Z AVIATION DISCUSSION. AVIATION...ONCE THE FRONT COMES THROUGH (WHICH IS VERY EARLY IN THE FORECAST)...CIGS WILL FALL TO IFR AT KCRP...KVCT AND KALI BUT BE MVFR AT KLRD. CIGS WILL FALL RAPIDLY AT THE EASTERN TERMINALS...BUT MAY TAKE A BIT OF TIME AT KLRD (BASED ON SATELLITE AND GUIDANCE). FRONT ALREADY THROUGH KVCT AND SHOULD BE THROUGH REMAINDER OF TERMINALS BY 02Z (AND PROBABLY EARLIER). SOME SHOWERS ALONG BOUNDARY EXPECTED...BUT THUNDER UNLIKELY BASED ON CAP WHICH IS EXPECTED TO HOLD THUNDER IN CHECK. RATHER WINDY TONIGHT WITH SUSTAINED WINDS AOA 20 KNOTS AND GUSTS AOA 30 KNOTS...BUT NOT AS STRONG AT KLRD. CONDITIONS IMPROVE TO MVFR...THEN VFR (BUT STILL CIGS) DURING THE DAY ON MONDAY. WINDS AND GUSTS FINALLY TAPER OFF DURING THE AFTERNOON. PREV DISCUSSION... /ISSUED 413 PM CST SUN MAR 2 2014/ SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...VERY STRONG COLD FRONT IS KNOCKING ON THE DOOR ACROSS THE NORTHERN ZONES. FRONT SHOULD ENTER THE AREA IN AN HOUR OR TWO AND MOVE THROUGH THE REMAINDER OF THE REGION THIS EVENING. ONLY SOME LIGHT SHOWERS HAVE DEVELOPED THIS FAR OVER THE NORTHEAST ZONES...WITH NO THUNDER REPORTED YET. THINK LOW CHANCES FOR SHOWERS WILL EXIST ALONG OF AND BEHIND THE FRONT THROUGH THE FIRST PART OF THE EVENING. TEMPERATURES WILL BEGIN TO TUMBLE BEHIND THE FRONT AND SOME LOCATIONS MAY BE ABOUT 40 TO 45 DEGREES COOLER MONDAY MORNING COMPARED TO RIGHT NOW. IN ADDITION TO THE COLDER TEMPS...STRONG WINDS WILL DEVELOP TONIGHT ESPECIALLY OVER THE COASTAL COUNTIES. QUITE A SPREAD IN GUIDANCE EXISTS BETWEEN MAV/MET WIND SPEEDS WITH THE MAV SUGGESTING WIND ADVISORY CONDITIONS. TEMPERED WIND SPEEDS A BIT BUT WINDY CONDITIONS WILL DEVELOP NONETHELESS WITH SPEEDS BETWEEN 20 AND 30 MPH. A WIND ADVISORY COULD BECOME NECESSARY IF SPEEDS ARE A LITTLE HIGHER. WIND CHILLS WILL BE AN ISSUE THOUGH OVER THE NORTHERN COASTAL BEND AND VICTORIA CROSSROADS REGION WHERE WC VALUES WILL FALL BETWEEN 20 AND 25 AFTER MIDNIGHT. HAVE ISSUED A WIND CHILL ADVISORY FOR THESE LOCATIONS. SOMETHING ALSO WORTH MONITORING WILL BE THE PRECIP CHANCES AFTER MIDNIGHT...AS THE LAST FEW HOURS OF THE HRRR HAS DEVELOPED PRECIP OVER MUCH OF SOUTH TEXAS. CONFIDENCE IS LOWER ON THIS SCENARIO...BUT HAVE KEPT SOME LOW POPS OVER THE SOUTHERN AND EASTERN AREAS. CLOUDY CONDITIONS AND NORTHERLY WINDS WILL KEEP TEMPERATURES DOWN IN THE 40S ON MONDAY. PRECIP CHANCES WILL RAMP BACK UP ON MONDAY NIGHT AS 850MB FLOW TURNS SOUTHERLY AND ISENTROPIC LIFT PATTERN BECOMES ESTABLISHED. MARINE...VERY STRONG OFFSHORE WINDS WILL DEVELOP OVER THE GULF WATERS BEHIND A COLD FRONT. GUSTS TO GALE FORCE BETWEEN 35 AND 40 KNOTS WILL BE LIKELY AND HAVE ISSUED A GALE WARNING OVER THE NEARSHORE AND OFFSHORE WATERS. SEAS WILL BUILD BETWEEN 6 AND 8 FEET OVER THE NEARSHORE WATERS AND 8 TO 10 FEET OVER THE OFFSHORE WATERS BY MONDAY MORNING. WIND SPEEDS WILL DIMINISH BY MID MORNING ON MONDAY BUT STILL REMAIN IN SMALL CRAFT ADVISORY LEVELS THROUGH THE AFTERNOON. LONG TERM (TUESDAY THROUGH SUNDAY)...S/W TROUGH AXIS WILL KICK EAST DURING THE DAY TUESDAY WITH DAYTIME PRECIP MAINLY CONFINED TO EASTERN ZONES AND DURING THE MORNING HOURS. AN INCREASE IN NVA SHOULD LIMIT PRECIP DURING THE AFTERNOON AND EARLY EVENING HOURS BEFORE SLIGHT CHANCES RETURN AFTER MIDNIGHT ACROSS EASTERN ZONES AS ANOTHER S/W TROUGH SKIRTS EAST ACROSS TX. THIS SYSTEM IS PROG TO BE A LITTLE FARTHER NORTH AND A LITTLE MORE MOISTURE STARVED THAN MON NIGHT/TUESDAY SYSTEM...AND THUS ONLY A SLIGHT CHANCE OF LIGHT PRECIP IS EXPECTED AT THIS TIME. NW FLOW FROM SFC TO UPPER LEVELS ON THURSDAY SHOULD LEAD TO SUNNIER AND DRIER CONDITIONS AREAWIDE. BRIEF ZONAL FLOW ALOFT ON FRIDAY TRANSITIONS TO MERIDIONAL BY THE WEEKEND WITH BOTH ECMWF/GFS WANTING TO BRING ANOTHER COLD FRONT INTO THE REGION. GUIDANCE IS ALSO WANTING TO CUT OFF A STRONG H5 LOW ACROSS NW MEX AND SHIFT IT EAST TOWARDS THE BIG BEND REGION. HAVE INCREASED POPS FOR LATTER PERIODS DUE TO INCREASED CONFIDENCE IN SEEING SOME PRECIP ACROSS THE AREA AS LOW PROGRESSES CLOSER. MAX TEMPS WILL REMAIN WELL BELOW NORMAL FOR TUES WITH ONLY TEMPERED MODIFICATION ON WEDNESDAY. MORE SUBSTANTIAL WARM UP EXPECTED THURS AND FRIDAY AND INTO SATURDAY BEFORE ANOTHER COLD FRONT POTENTIALLY IMPACTS THE AREA LATE IN THE LONG TERM PERIOD. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 35 47 38 44 44 / 30 20 50 50 20 VICTORIA 33 47 36 42 41 / 30 10 50 50 20 LAREDO 38 46 39 52 47 / 10 10 20 10 10 ALICE 35 46 38 45 43 / 20 10 40 40 20 ROCKPORT 33 48 39 45 45 / 30 20 50 50 20 COTULLA 36 49 37 48 44 / 10 10 30 10 10 KINGSVILLE 35 45 38 46 44 / 30 20 50 50 20 NAVY CORPUS 37 46 41 45 45 / 30 20 50 50 20 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...WIND CHILL ADVISORY UNTIL 9 AM CST MONDAY FOR THE FOLLOWING ZONES: ARANSAS...BEE...CALHOUN...DUVAL...GOLIAD...JIM WELLS...KLEBERG...LA SALLE...LIVE OAK...MCMULLEN...NUECES... REFUGIO...SAN PATRICIO...VICTORIA...WEBB. GM...SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. GALE WARNING UNTIL 9 AM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM... COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. SMALL CRAFT ADVISORY UNTIL 6 PM CST MONDAY FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS... BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR. && $$ TE/81...SHORT TERM
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
659 PM CST SUN MAR 2 2014 .DISCUSSION...STRONG COLD FRONT IS MOVING THROUGH THE CWA A LITTLE FASTER BY A COUPLE OF HOURS THAN PREVIOUSLY ANTCIPATED. HAVE UPDATED FCST TO ACCOUNT FOR THE FASTER FROPA AND WENT EARLIER WITH THE SMALL CRAFT ADVISORY FOR THE BAYS. WINDS BEHIND THE FROPA HAVE BEEN INITIALLY GUSTING BETWEEN 30-40 KNOTS THEN DECREASING TO 28-35KTS...THEREFORE AM NOT ANTCIPATING WIND ADVISORY CONDITIONS AT THIS TIME. HOWEVER...WIND CHILL ADVISORY FOR THE VICTORIA CROSSROADS REMAINS IN EFFECT. ISOLD SHRA`S HAVE ALSO BEEN DVLPG ALONG AND BEHIND THE FRONT...BUT IS EXPECTED TO DIMINISH OVERNIGHT FROM NW TO SE. SOME MODELS PROG MN TEMPS OF 31 DEGREES AROUND VCT BUT THINK CLOUD COVER AND STRONG WINDS WILL KEEP MN TEMPS JUST ABV FREEZING BUT A BRIEF DIP TO 32 DEGREES AROUND SUNRISE ACROSS A FEW LOCATIONS ACROSS THE NRN CWA IS NOT OUT OF THE QUESTION. ONLY MADE TWEAKS TO TEMPS/DEWPOINTS/WSHFT TO ACCOUNT FOR THE FASTER FROPA. && .PREV DISCUSSION... /ISSUED 548 PM CST SUN MAR 2 2014/ DISCUSSION...SEE 00Z AVIATION DISCUSSION. AVIATION...ONCE THE FRONT COMES THROUGH (WHICH IS VERY EARLY IN THE FORECAST)...CIGS WILL FALL TO IFR AT KCRP...KVCT AND KALI BUT BE MVFR AT KLRD. CIGS WILL FALL RAPIDLY AT THE EASTERN TERMINALS...BUT MAY TAKE A BIT OF TIME AT KLRD (BASED ON SATELLITE AND GUIDANCE). FRONT ALREADY THROUGH KVCT AND SHOULD BE THROUGH REMAINDER OF TERMINALS BY 02Z (AND PROBABLY EARLIER). SOME SHOWERS ALONG BOUNDARY EXPECTED...BUT THUNDER UNLIKELY BASED ON CAP WHICH IS EXPECTED TO HOLD THUNDER IN CHECK. RATHER WINDY TONIGHT WITH SUSTAINED WINDS AOA 20 KNOTS AND GUSTS AOA 30 KNOTS...BUT NOT AS STRONG AT KLRD. CONDITIONS IMPROVE TO MVFR...THEN VFR (BUT STILL CIGS) DURING THE DAY ON MONDAY. WINDS AND GUSTS FINALLY TAPER OFF DURING THE AFTERNOON. PREV DISCUSSION... /ISSUED 413 PM CST SUN MAR 2 2014/ SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...VERY STRONG COLD FRONT IS KNOCKING ON THE DOOR ACROSS THE NORTHERN ZONES. FRONT SHOULD ENTER THE AREA IN AN HOUR OR TWO AND MOVE THROUGH THE REMAINDER OF THE REGION THIS EVENING. ONLY SOME LIGHT SHOWERS HAVE DEVELOPED THIS FAR OVER THE NORTHEAST ZONES...WITH NO THUNDER REPORTED YET. THINK LOW CHANCES FOR SHOWERS WILL EXIST ALONG OF AND BEHIND THE FRONT THROUGH THE FIRST PART OF THE EVENING. TEMPERATURES WILL BEGIN TO TUMBLE BEHIND THE FRONT AND SOME LOCATIONS MAY BE ABOUT 40 TO 45 DEGREES COOLER MONDAY MORNING COMPARED TO RIGHT NOW. IN ADDITION TO THE COLDER TEMPS...STRONG WINDS WILL DEVELOP TONIGHT ESPECIALLY OVER THE COASTAL COUNTIES. QUITE A SPREAD IN GUIDANCE EXISTS BETWEEN MAV/MET WIND SPEEDS WITH THE MAV SUGGESTING WIND ADVISORY CONDITIONS. TEMPERED WIND SPEEDS A BIT BUT WINDY CONDITIONS WILL DEVELOP NONETHELESS WITH SPEEDS BETWEEN 20 AND 30 MPH. A WIND ADVISORY COULD BECOME NECESSARY IF SPEEDS ARE A LITTLE HIGHER. WIND CHILLS WILL BE AN ISSUE THOUGH OVER THE NORTHERN COASTAL BEND AND VICTORIA CROSSROADS REGION WHERE WC VALUES WILL FALL BETWEEN 20 AND 25 AFTER MIDNIGHT. HAVE ISSUED A WIND CHILL ADVISORY FOR THESE LOCATIONS. SOMETHING ALSO WORTH MONITORING WILL BE THE PRECIP CHANCES AFTER MIDNIGHT...AS THE LAST FEW HOURS OF THE HRRR HAS DEVELOPED PRECIP OVER MUCH OF SOUTH TEXAS. CONFIDENCE IS LOWER ON THIS SCENARIO...BUT HAVE KEPT SOME LOW POPS OVER THE SOUTHERN AND EASTERN AREAS. CLOUDY CONDITIONS AND NORTHERLY WINDS WILL KEEP TEMPERATURES DOWN IN THE 40S ON MONDAY. PRECIP CHANCES WILL RAMP BACK UP ON MONDAY NIGHT AS 850MB FLOW TURNS SOUTHERLY AND ISENTROPIC LIFT PATTERN BECOMES ESTABLISHED. MARINE...VERY STRONG OFFSHORE WINDS WILL DEVELOP OVER THE GULF WATERS BEHIND A COLD FRONT. GUSTS TO GALE FORCE BETWEEN 35 AND 40 KNOTS WILL BE LIKELY AND HAVE ISSUED A GALE WARNING OVER THE NEARSHORE AND OFFSHORE WATERS. SEAS WILL BUILD BETWEEN 6 AND 8 FEET OVER THE NEARSHORE WATERS AND 8 TO 10 FEET OVER THE OFFSHORE WATERS BY MONDAY MORNING. WIND SPEEDS WILL DIMINISH BY MID MORNING ON MONDAY BUT STILL REMAIN IN SMALL CRAFT ADVISORY LEVELS THROUGH THE AFTERNOON. LONG TERM (TUESDAY THROUGH SUNDAY)...S/W TROUGH AXIS WILL KICK EAST DURING THE DAY TUESDAY WITH DAYTIME PRECIP MAINLY CONFINED TO EASTERN ZONES AND DURING THE MORNING HOURS. AN INCREASE IN NVA SHOULD LIMIT PRECIP DURING THE AFTERNOON AND EARLY EVENING HOURS BEFORE SLIGHT CHANCES RETURN AFTER MIDNIGHT ACROSS EASTERN ZONES AS ANOTHER S/W TROUGH SKIRTS EAST ACROSS TX. THIS SYSTEM IS PROG TO BE A LITTLE FARTHER NORTH AND A LITTLE MORE MOISTURE STARVED THAN MON NIGHT/TUESDAY SYSTEM...AND THUS ONLY A SLIGHT CHANCE OF LIGHT PRECIP IS EXPECTED AT THIS TIME. NW FLOW FROM SFC TO UPPER LEVELS ON THURSDAY SHOULD LEAD TO SUNNIER AND DRIER CONDITIONS AREAWIDE. BRIEF ZONAL FLOW ALOFT ON FRIDAY TRANSITIONS TO MERIDIONAL BY THE WEEKEND WITH BOTH ECMWF/GFS WANTING TO BRING ANOTHER COLD FRONT INTO THE REGION. GUIDANCE IS ALSO WANTING TO CUT OFF A STRONG H5 LOW ACROSS NW MEX AND SHIFT IT EAST TOWARDS THE BIG BEND REGION. HAVE INCREASED POPS FOR LATTER PERIODS DUE TO INCREASED CONFIDENCE IN SEEING SOME PRECIP ACROSS THE AREA AS LOW PROGRESSES CLOSER. MAX TEMPS WILL REMAIN WELL BELOW NORMAL FOR TUES WITH ONLY TEMPERED MODIFICATION ON WEDNESDAY. MORE SUBSTANTIAL WARM UP EXPECTED THURS AND FRIDAY AND INTO SATURDAY BEFORE ANOTHER COLD FRONT POTENTIALLY IMPACTS THE AREA LATE IN THE LONG TERM PERIOD. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 35 47 38 44 44 / 30 20 50 50 20 VICTORIA 33 47 36 42 41 / 30 10 50 50 20 LAREDO 38 46 39 52 47 / 10 10 20 10 10 ALICE 35 46 38 45 43 / 20 10 40 40 20 ROCKPORT 33 48 39 45 45 / 30 20 50 50 20 COTULLA 36 49 37 48 44 / 10 10 30 10 10 KINGSVILLE 35 45 38 46 44 / 30 20 50 50 20 NAVY CORPUS 37 46 41 45 45 / 30 20 50 50 20 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST MONDAY FOR THE FOLLOWING ZONES: ARANSAS...CALHOUN...GOLIAD...REFUGIO... VICTORIA. GM...SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. GALE WARNING FROM 10 PM THIS EVENING TO 9 AM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. SMALL CRAFT ADVISORY UNTIL 6 PM CST MONDAY FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS... BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR. && $$ TE/81...SHORT TERM
AREA FORECAST DISCUSSION...CORRECTED
NWS CORPUS CHRISTI TX
548 PM CST SUN MAR 2 2014 .DISCUSSION...SEE 00Z AVIATION DISCUSSION. && .AVIATION...ONCE THE FRONT COMES THROUGH (WHICH IS VERY EARLY IN THE FORECAST)...CIGS WILL FALL TO IFR AT KCRP...KVCT AND KALI BUT BE MVFR AT KLRD. CIGS WILL FALL RAPIDLY AT THE EASTERN TERMINALS...BUT MAY TAKE A BIT OF TIME AT KLRD (BASED ON SATELLITE AND GUIDANCE). FRONT ALREADY THROUGH KVCT AND SHOULD BE THROUGH REMAINDER OF TERMINALS BY 02Z (AND PROBABLY EARLIER). SOME SHOWERS ALONG BOUNDARY EXPECTED...BUT THUNDER UNLIKELY BASED ON CAP WHICH IS EXPECTED TO HOLD THUNDER IN CHECK. RATHER WINDY TONIGHT WITH SUSTAINED WINDS AOA 20 KNOTS AND GUSTS AOA 30 KNOTS...BUT NOT AS STRONG AT KLRD. CONDITIONS IMPROVE TO MVFR...THEN VFR (BUT STILL CIGS) DURING THE DAY ON MONDAY. WINDS AND GUSTS FINALLY TAPER OFF DURING THE AFTERNOON. && .PREV DISCUSSION... /ISSUED 413 PM CST SUN MAR 2 2014/ SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...VERY STRONG COLD FRONT IS KNOCKING ON THE DOOR ACROSS THE NORTHERN ZONES. FRONT SHOULD ENTER THE AREA IN AN HOUR OR TWO AND MOVE THROUGH THE REMAINDER OF THE REGION THIS EVENING. ONLY SOME LIGHT SHOWERS HAVE DEVELOPED THIS FAR OVER THE NORTHEAST ZONES...WITH NO THUNDER REPORTED YET. THINK LOW CHANCES FOR SHOWERS WILL EXIST ALONG OF AND BEHIND THE FRONT THROUGH THE FIRST PART OF THE EVENING. TEMPERATURES WILL BEGIN TO TUMBLE BEHIND THE FRONT AND SOME LOCATIONS MAY BE ABOUT 40 TO 45 DEGREES COOLER MONDAY MORNING COMPARED TO RIGHT NOW. IN ADDITION TO THE COLDER TEMPS...STRONG WINDS WILL DEVELOP TONIGHT ESPECIALLY OVER THE COASTAL COUNTIES. QUITE A SPREAD IN GUIDANCE EXISTS BETWEEN MAV/MET WIND SPEEDS WITH THE MAV SUGGESTING WIND ADVISORY CONDITIONS. TEMPERED WIND SPEEDS A BIT BUT WINDY CONDITIONS WILL DEVELOP NONETHELESS WITH SPEEDS BETWEEN 20 AND 30 MPH. A WIND ADVISORY COULD BECOME NECESSARY IF SPEEDS ARE A LITTLE HIGHER. WIND CHILLS WILL BE AN ISSUE THOUGH OVER THE NORTHERN COASTAL BEND AND VICTORIA CROSSROADS REGION WHERE WC VALUES WILL FALL BETWEEN 20 AND 25 AFTER MIDNIGHT. HAVE ISSUED A WIND CHILL ADVISORY FOR THESE LOCATIONS. SOMETHING ALSO WORTH MONITORING WILL BE THE PRECIP CHANCES AFTER MIDNIGHT...AS THE LAST FEW HOURS OF THE HRRR HAS DEVELOPED PRECIP OVER MUCH OF SOUTH TEXAS. CONFIDENCE IS LOWER ON THIS SCENARIO...BUT HAVE KEPT SOME LOW POPS OVER THE SOUTHERN AND EASTERN AREAS. CLOUDY CONDITIONS AND NORTHERLY WINDS WILL KEEP TEMPERATURES DOWN IN THE 40S ON MONDAY. PRECIP CHANCES WILL RAMP BACK UP ON MONDAY NIGHT AS 850MB FLOW TURNS SOUTHERLY AND ISENTROPIC LIFT PATTERN BECOMES ESTABLISHED. MARINE...VERY STRONG OFFSHORE WINDS WILL DEVELOP OVER THE GULF WATERS BEHIND A COLD FRONT. GUSTS TO GALE FORCE BETWEEN 35 AND 40 KNOTS WILL BE LIKELY AND HAVE ISSUED A GALE WARNING OVER THE NEARSHORE AND OFFSHORE WATERS. SEAS WILL BUILD BETWEEN 6 AND 8 FEET OVER THE NEARSHORE WATERS AND 8 TO 10 FEET OVER THE OFFSHORE WATERS BY MONDAY MORNING. WIND SPEEDS WILL DIMINISH BY MID MORNING ON MONDAY BUT STILL REMAIN IN SMALL CRAFT ADVISORY LEVELS THROUGH THE AFTERNOON. LONG TERM (TUESDAY THROUGH SUNDAY)...S/W TROUGH AXIS WILL KICK EAST DURING THE DAY TUESDAY WITH DAYTIME PRECIP MAINLY CONFINED TO EASTERN ZONES AND DURING THE MORNING HOURS. AN INCREASE IN NVA SHOULD LIMIT PRECIP DURING THE AFTERNOON AND EARLY EVENING HOURS BEFORE SLIGHT CHANCES RETURN AFTER MIDNIGHT ACROSS EASTERN ZONES AS ANOTHER S/W TROUGH SKIRTS EAST ACROSS TX. THIS SYSTEM IS PROG TO BE A LITTLE FARTHER NORTH AND A LITTLE MORE MOISTURE STARVED THAN MON NIGHT/TUESDAY SYSTEM...AND THUS ONLY A SLIGHT CHANCE OF LIGHT PRECIP IS EXPECTED AT THIS TIME. NW FLOW FROM SFC TO UPPER LEVELS ON THURSDAY SHOULD LEAD TO SUNNIER AND DRIER CONDITIONS AREAWIDE. BRIEF ZONAL FLOW ALOFT ON FRIDAY TRANSITIONS TO MERIDIONAL BY THE WEEKEND WITH BOTH ECMWF/GFS WANTING TO BRING ANOTHER COLD FRONT INTO THE REGION. GUIDANCE IS ALSO WANTING TO CUT OFF A STRONG H5 LOW ACROSS NW MEX AND SHIFT IT EAST TOWARDS THE BIG BEND REGION. HAVE INCREASED POPS FOR LATTER PERIODS DUE TO INCREASED CONFIDENCE IN SEEING SOME PRECIP ACROSS THE AREA AS LOW PROGRESSES CLOSER. MAX TEMPS WILL REMAIN WELL BELOW NORMAL FOR TUES WITH ONLY TEMPERED MODIFICATION ON WEDNESDAY. MORE SUBSTANTIAL WARM UP EXPECTED THURS AND FRIDAY AND INTO SATURDAY BEFORE ANOTHER COLD FRONT POTENTIALLY IMPACTS THE AREA LATE IN THE LONG TERM PERIOD. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 35 47 38 44 44 / 30 20 50 50 20 VICTORIA 33 47 36 42 41 / 30 10 50 50 20 LAREDO 38 46 39 52 47 / 10 10 20 10 10 ALICE 35 46 38 45 43 / 20 10 40 40 20 ROCKPORT 33 48 39 45 45 / 30 20 50 50 20 COTULLA 36 49 37 48 44 / 10 10 30 10 10 KINGSVILLE 35 45 38 46 44 / 30 20 50 50 20 NAVY CORPUS 37 46 41 45 45 / 30 20 50 50 20 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST MONDAY FOR THE FOLLOWING ZONES: ARANSAS...CALHOUN...GOLIAD...REFUGIO... VICTORIA. GM...SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. GALE WARNING FROM 10 PM THIS EVENING TO 9 AM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 6 PM CST MONDAY FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR. && $$ GW/86...AVIATION
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
525 PM CST SUN MAR 2 2014 .DISCUSSION... && .AVIATION...ONCE THE FRONT COMES THROUGH (WHICH IS VERY EARLY IN THE FORECAST)...CIGS WILL FALL TO IFR AT KCRP...KVCT AND KALI BUT BE MVFR AT KLRD. CIGS WILL FALL RAPIDLY AT THE EASTERN TERMINALS...BUT MAY TAKE A BIT OF TIME AT KLRD (BASED ON SATELLITE AND GUIDANCE). FRONT ALREADY THROUGH KVCT AND SHOULD BE THROUGH REMAINDER OF TERMINALS BY 02Z (AND PROBABLY EARLIER). SOME SHOWERS ALONG BOUNDARY EXPECTED...BUT THUNDER UNLIKELY BASED ON CAP WHICH IS EXPECTED TO HOLD THUNDER IN CHECK. RATHER WINDY TONIGHT WITH SUSTAINED WINDS AOA 20 KNOTS AND GUSTS AOA 30 KNOTS...BUT NOT AS STRONG AT KLRD. CONDITIONS IMPROVE TO MVFR...THEN VFR (BUT STILL CIGS) DURING THE DAY ON MONDAY. WINDS AND GUSTS FINALLY TAPER OFF DURING THE AFTERNOON. && .PREV DISCUSSION... /ISSUED 413 PM CST SUN MAR 2 2014/ SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...VERY STRONG COLD FRONT IS KNOCKING ON THE DOOR ACROSS THE NORTHERN ZONES. FRONT SHOULD ENTER THE AREA IN AN HOUR OR TWO AND MOVE THROUGH THE REMAINDER OF THE REGION THIS EVENING. ONLY SOME LIGHT SHOWERS HAVE DEVELOPED THIS FAR OVER THE NORTHEAST ZONES...WITH NO THUNDER REPORTED YET. THINK LOW CHANCES FOR SHOWERS WILL EXIST ALONG OF AND BEHIND THE FRONT THROUGH THE FIRST PART OF THE EVENING. TEMPERATURES WILL BEGIN TO TUMBLE BEHIND THE FRONT AND SOME LOCATIONS MAY BE ABOUT 40 TO 45 DEGREES COOLER MONDAY MORNING COMPARED TO RIGHT NOW. IN ADDITION TO THE COLDER TEMPS...STRONG WINDS WILL DEVELOP TONIGHT ESPECIALLY OVER THE COASTAL COUNTIES. QUITE A SPREAD IN GUIDANCE EXISTS BETWEEN MAV/MET WIND SPEEDS WITH THE MAV SUGGESTING WIND ADVISORY CONDITIONS. TEMPERED WIND SPEEDS A BIT BUT WINDY CONDITIONS WILL DEVELOP NONETHELESS WITH SPEEDS BETWEEN 20 AND 30 MPH. A WIND ADVISORY COULD BECOME NECESSARY IF SPEEDS ARE A LITTLE HIGHER. WIND CHILLS WILL BE AN ISSUE THOUGH OVER THE NORTHERN COASTAL BEND AND VICTORIA CROSSROADS REGION WHERE WC VALUES WILL FALL BETWEEN 20 AND 25 AFTER MIDNIGHT. HAVE ISSUED A WIND CHILL ADVISORY FOR THESE LOCATIONS. SOMETHING ALSO WORTH MONITORING WILL BE THE PRECIP CHANCES AFTER MIDNIGHT...AS THE LAST FEW HOURS OF THE HRRR HAS DEVELOPED PRECIP OVER MUCH OF SOUTH TEXAS. CONFIDENCE IS LOWER ON THIS SCENARIO...BUT HAVE KEPT SOME LOW POPS OVER THE SOUTHERN AND EASTERN AREAS. CLOUDY CONDITIONS AND NORTHERLY WINDS WILL KEEP TEMPERATURES DOWN IN THE 40S ON MONDAY. PRECIP CHANCES WILL RAMP BACK UP ON MONDAY NIGHT AS 850MB FLOW TURNS SOUTHERLY AND ISENTROPIC LIFT PATTERN BECOMES ESTABLISHED. MARINE...VERY STRONG OFFSHORE WINDS WILL DEVELOP OVER THE GULF WATERS BEHIND A COLD FRONT. GUSTS TO GALE FORCE BETWEEN 35 AND 40 KNOTS WILL BE LIKELY AND HAVE ISSUED A GALE WARNING OVER THE NEARSHORE AND OFFSHORE WATERS. SEAS WILL BUILD BETWEEN 6 AND 8 FEET OVER THE NEARSHORE WATERS AND 8 TO 10 FEET OVER THE OFFSHORE WATERS BY MONDAY MORNING. WIND SPEEDS WILL DIMINISH BY MID MORNING ON MONDAY BUT STILL REMAIN IN SMALL CRAFT ADVISORY LEVELS THROUGH THE AFTERNOON. LONG TERM (TUESDAY THROUGH SUNDAY)...S/W TROUGH AXIS WILL KICK EAST DURING THE DAY TUESDAY WITH DAYTIME PRECIP MAINLY CONFINED TO EASTERN ZONES AND DURING THE MORNING HOURS. AN INCREASE IN NVA SHOULD LIMIT PRECIP DURING THE AFTERNOON AND EARLY EVENING HOURS BEFORE SLIGHT CHANCES RETURN AFTER MIDNIGHT ACROSS EASTERN ZONES AS ANOTHER S/W TROUGH SKIRTS EAST ACROSS TX. THIS SYSTEM IS PROG TO BE A LITTLE FARTHER NORTH AND A LITTLE MORE MOISTURE STARVED THAN MON NIGHT/TUESDAY SYSTEM...AND THUS ONLY A SLIGHT CHANCE OF LIGHT PRECIP IS EXPECTED AT THIS TIME. NW FLOW FROM SFC TO UPPER LEVELS ON THURSDAY SHOULD LEAD TO SUNNIER AND DRIER CONDITIONS AREAWIDE. BRIEF ZONAL FLOW ALOFT ON FRIDAY TRANSITIONS TO MERIDIONAL BY THE WEEKEND WITH BOTH ECMWF/GFS WANTING TO BRING ANOTHER COLD FRONT INTO THE REGION. GUIDANCE IS ALSO WANTING TO CUT OFF A STRONG H5 LOW ACROSS NW MEX AND SHIFT IT EAST TOWARDS THE BIG BEND REGION. HAVE INCREASED POPS FOR LATTER PERIODS DUE TO INCREASED CONFIDENCE IN SEEING SOME PRECIP ACROSS THE AREA AS LOW PROGRESSES CLOSER. MAX TEMPS WILL REMAIN WELL BELOW NORMAL FOR TUES WITH ONLY TEMPERED MODIFICATION ON WEDNESDAY. MORE SUBSTANTIAL WARM UP EXPECTED THURS AND FRIDAY AND INTO SATURDAY BEFORE ANOTHER COLD FRONT POTENTIALLY IMPACTS THE AREA LATE IN THE LONG TERM PERIOD. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 35 47 38 44 44 / 30 20 50 50 20 VICTORIA 33 47 36 42 41 / 30 10 50 50 20 LAREDO 38 46 39 52 47 / 10 10 20 10 10 ALICE 35 46 38 45 43 / 20 10 40 40 20 ROCKPORT 33 48 39 45 45 / 30 20 50 50 20 COTULLA 36 49 37 48 44 / 10 10 30 10 10 KINGSVILLE 35 45 38 46 44 / 30 20 50 50 20 NAVY CORPUS 37 46 41 45 45 / 30 20 50 50 20 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST MONDAY FOR THE FOLLOWING ZONES: ARANSAS...CALHOUN...GOLIAD...REFUGIO... VICTORIA. GM...SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. GALE WARNING FROM 10 PM THIS EVENING TO 9 AM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 6 PM CST MONDAY FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR. && $$ GW/86...AVIATION
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
409 PM CST SAT MAR 1 2014 .DISCUSSION... REGARDING THE WINTER WEATHER ADVISORY ACROSS NORTH AND CENTRAL TEXAS...WENT AHEAD AND EXPANDED THE ADVISORY SOUTH TO A CISCO TO CLIFTON TO ATHENS LINE WITH THE AFTERNOON FORECAST PACKAGE. THE BIGGEST IMPACTS FROM FREEZING RAIN AND/OR SLEET ACCUMULATIONS ARE STILL EXPECTED TO OCCUR ALONG AND NORTH OF A LINE FROM GRAHAM TO PLANO TO SULPHUR SPRINGS. POINTS SOUTH OF THIS LINE TO THE SOUTHERN EDGE OF THE WINTER WEATHER ADVISORY ARE STILL EXPECTED TO SEE IMPACTS FROM LIGHT ICE ACCUMULATIONS...BUT THESE IMPACTS ARE EXPECTED TO BE FOCUSED ON ELEVATED SURFACES...IN PART DUE TO THE VERY WARM TEMPERATURES ACROSS THE REGION TODAY. DETAILS REGARDING THE FORECAST CONTINUE BELOW: A 21Z SUBJECTIVE SURFACE ANALYSIS INDICATED A BOUNDARY LIFTING SLOWLY NORTH TOWARDS THE RED RIVER WHERE MOST GUIDANCE INDICATES IT WILL STALL OUT BY SUNSET. TEMPERATURES ACROSS NORTH TEXAS WERE GENERALLY IN THE MID TO UPPER 70S FOR MOST LOCATIONS...WITH A NOTABLE EXCEPTION SOUTHWEST OF THE DFW AREA...WHERE TEMPERATURES SPIKED INTO THE MID TO UPPER 80S ALONG AN 850 MB THERMAL RIDGE. WITH TEMPERATURES TOPPING OUT IN THE 70S TO 80S ON CONSECUTIVE DAYS FOR MOST POINTS ACROSS NORTH AND CENTRAL TEXAS...SOIL TEMPERATURES ARE WARM...AND THIS WILL PLAY AN IMPORTANT ROLE IN OUR FORECAST OVER THE NEXT 24 HOURS. TO OUR NORTH...21Z SURFACE OBSERVATIONS ACROSS SOUTHERN KANSAS AND NORTHERN OKLAHOMA RANGED FROM THE LOWER TEENS TO THE MIDDLE 20S. COMPARING THESE TEMPERATURES TO THE MORNING NAM 21Z FORECAST FOR SURFACE TEMPERATURES INDICATED THAT THE NAM WAS RUNNING 8 TO 10 DEGREES TOO WARM WITH AIR ASSOCIATED WITH THE ARCTIC FRONT. UNFORTUNATELY THE NAM IS THE COLDEST OF THE POPULAR OPERATIONAL FORECAST MODELS...SO THERE ARE SOME SIGNIFICANT SHORT TERM SURFACE TEMPERATURE ISSUES TO CONTEND WITH IN THE FORECAST MODELS MOVING FORWARD. THE RAP IS DOING THE BEST JOB RESOLVING 21Z TEMPERATURES...BUT THAT IS LARGELY DUE TO THE FACT THAT THE RAP INGESTS NEW DATA EACH HOUR. AT ANY RATE...CONTINUED TO RELY UPON THE NAM HEAVILY WITH THIS FORECAST PACKAGE...JUST LIKE THE MIDNIGHT CREW...BECAUSE THE NAM IS THE COLDEST AND FASTEST WITH THIS ARCTIC COLD FRONT OVER THE NEXT 24 HOURS. DUE TO THE PRESENCE OF TWO BOUNDARIES IN THE AREA (THE NEARLY STATIONARY FRONT NEAR THE RED RIVER...THEN THE ARCTIC FRONT TO THE NORTH) IT WAS DIFFICULT TO TRACK THE SOUTHERN PROGRESS OF THE ARCTIC FRONT EARLY THIS AFTERNOON. THIS IS PARTIALLY DUE TO MOSTLY CLOUDY SKIES NORTH OF THE RED RIVER FRONT...AND PARTIALLY DUE TO NORTHERLY WINDS EXTENDING FROM THE RED RIVER NORTH THROUGH KANSAS MASKING THE WIND SHIFT ASSOCIATED WITH THE TRULY ARCTIC AIRMASS. BASED ON HOURLY TEMPERATURE TRENDS...AT 21Z THE FRONT APPEARED TO BE NEAR A LINE FROM CANADIAN TX TO WATONGA OK TO PONCA CITY OK. TRACKING THIS FRONT WILL ALSO PLAY AN IMPORTANT ROLE IN THE FORECAST FOR PRECIPITATION TYPE OVER THE NEXT 24 HOURS AS A FASTER OR SLOWER FRONTAL PASSAGE COULD HAVE DRASTIC IMPACTS ON OUR FORECAST AND IMPACTS. TO THE FORECAST...THE COLD FRONT IS EXPECTED TO ARRIVE AT THE RED RIVER JUST AFTER MIDNIGHT TONIGHT...PUSHING INTO THE DFW AREA BETWEEN 3 AND 4 AM CST. THE FRONT IS EXPECTED TO PASS ACROSS WACO AROUND 7 AM...AND THEN ACROSS PALESTINE AND TEMPLE/KILLEEN AN HOUR LATER. THE FRONT IS EXPECTED TO BE SOUTHEAST OF THE FORT WORTH CWA BEFORE NOON. AHEAD OF THE FRONT...REGARDING THUNDERSTORM AND SEVERE WEATHER CHANCES. PARAMETERS ARE THERE INDICATIVE OF A SEVERE THUNDERSTORM THREAT WITH DEW POINTS IN THE LOWER TO MID 60S IN PLACE CURRENTLY ACROSS MUCH OF CENTRAL TEXAS. MODELS INDICATE THAT THERE WILL BE AROUND 1000 J/KG OF CAPE FOR STORMS AND KEEP LAYER BULK SHEAR OF AROUND 50 KTS. TAKEN AT FACE VALUE THE INTERSECTION OF THIS PARAMETER SPACE IS SUPPORTIVE OF ORGANIZED STORMS...PROBABLY SUPERCELLS OR POSSIBLY MULTI-CELL CLUSTERS ASSUMING STRONG FORCING ALONG THE COLD FRONT IS LARGELY RESPONSIBLE FOR RELEASING THE POTENTIAL CONVECTIVE ENERGY INTO STORMS. THE PROBLEM IS THAT THE CONSENSUS OF MODEL GUIDANCE SHOWS A LARGE CAPPING INVERSION IN THE 850 TO 800 MB LAYER...WHICH IS QUITE STOUT AT 300 TO 400 J/KG OF CONVECTIVE INHIBITION FOR SURFACE BASED AIR PARCELS AHEAD OF THE FRONT. FORECAST SOUNDINGS DO INDICATE THAT STRONG LIFT ASSOCIATED WITH THE ARCTIC FRONT WILL LIFT AND COOL A LARGE CHUNK OF THIS CAPPING INVERSION...HOWEVER THE CAP APPEARS TO BE CONSISTENTLY IN PLACE UNTIL 2-3 HOURS BEHIND THE FRONT. THIS BEING THE CASE...THERE WOULD BE NEARLY A ZERO CHANCE OF SURFACE BASED STORMS AND TORNADOES ACROSS THE CWA OUT AHEAD OF THE FRONT TOMORROW MORNING. DAMAGING WIND MAY BE POSSIBLE...HOWEVER STORMS ARE EXPECTED TO BECOME QUITE ELEVATED BEHIND THE FRONT...SO ANY VERTICAL MOTIONS WITHIN THE FRONTAL INVERSION ARE EXPECTED TO BE DAMPENED BY HIGH STABILITY. THAT LEAVES A CHANCE FOR ELEVATED STORMS CAPABLE OF PRODUCING HAIL...WHICH CANNOT BE RULED OUT AT THIS TIME. LEFT A MENTION OF AN ELEVATED RISK FOR SEVERE STORMS ACROSS THE FAR SOUTHEASTERN CWA FOR TOMORROW MORNING AS A RESULT IN OUR GRAPHICAL HAZARD IMAGES. BEHIND THE FRONT...FORECAST SOUNDINGS ARE SUPPORTIVE OF SCATTERED PRECIPITATION ASSOCIATED WITH PERSISTENT ISENTROPIC UPGLIDE AND FRONTOGENETIC FORCING FOR ASCENT OVER ALL OF NORTH AND CENTRAL TEXAS. WENT AHEAD AND BUMPED POPS UP TO 80 PERCENT FOR MOST LOCATIONS SUNDAY MORNING AS CHANCES FOR ALL LOCATIONS TO RECEIVE AT LEAST ONE HUNDREDTH OF AN INCH OF PRECIPITATION LOOKS VERY HIGH AT THIS TIME. MOST PRECIPITATION SUNDAY MORNING IS EXPECTED TO BE LIGHT...HOWEVER CANNOT RULE OUT SOME EMBEDDED THUNDERSTORMS AS AIR PARCELS LIFTED FROM THE 900 TO 850 MB LAYER ARE CONSISTENTLY FORECAST TO HAVE 3-500 J/KG OF POSITIVE CAPE. MORE WIDESPREAD PRECIPITATION IS EXPECTED TO OCCUR SUNDAY AFTERNOON UNFORTUNATELY AS A STRONG SHORTWAVE TROUGH CURRENTLY OVER SOUTHERN CALIFORNIA SPREADS LARGE SCALE FORCING FOR ASCENT OVER THE CWA. THIS IS UNFORTUNATE BECAUSE THE ARCTIC AIRMASS WILL BE THROUGH THE ENTIRE CWA BY THIS TIME WITH SUB-FREEZING TEMPERATURES BUILDING QUICKLY SOUTHEAST THROUGH THE AFTERNOON HOURS OF THE DAY. DEPENDING ON HOW FAST TEMPERATURES FALL BEHIND THE FRONT...WE SHOULD SEE A TRANSITION FROM RAIN SHOWERS TO FREEZING RAIN...TO FREEZING RAIN MIXED WITH SLEET TO ALL SLEET THROUGHOUT THE DAY AS THE ARCTIC AIRMASS CONTINUES TO BUILD INTO THE AREA FROM THE NORTHWEST. AT THIS TIME HAVE THE BEST CHANCES FOR ACCUMULATING ICE AND SLEET FOR LOCATIONS ALONG AND NORTH OF A LINE FROM GRAHAM TO PLANO TO SULPHUR SPRINGS AS THESE LOCATIONS ARE MOST LIKELY TO SPEND MOST OF THE DAY SUNDAY AT OR BELOW FREEZING. FROM THIS LINE SOUTH TO A LINE FROM CISCO TO CLIFTON TO ATHENS (THIS INCLUDES THE DFW METROPLEX)...EXPECT LESSER AMOUNTS OF ICE AND SLEET ACCUMULATION SIMPLY BECAUSE THE SUB-FREEZING AIR IS SLOWER TO BUILD IN...AND THESE AREAS SAW TEMPERATURES CLIMB ABOUT 10 DEGREES HIGHER TODAY THAN LOCATIONS FURTHER NORTH. ICE ACCUMULATIONS ARE VERY HARD TO PIN DOWN BECAUSE WE HAVE BEEN SO WARM OVER THE PAST 48 HOURS. JUST LOOKING AT MODEL OUTPUT AND FORECAST WATER EQUIVALENT PRECIPITATION AND CONVERTING THAT DIRECTLY INTO ICE IS A VERY POOR ESTIMATE OF ICE ACCUMULATION FOR THIS EVENT BECAUSE SOIL TEMPERATURES ARE IN THE MID TO UPPER 50S ACROSS THE CWA. IT WILL TAKE QUITE A BIT OF TIME FOR SOIL TEMPERATURES TO FALL...MEANING THAT A LARGE PORTION OF ANY LIQUID PRECIPITATION THAT FALLS...EVEN WITH TEMPERATURES BELOW FREEZING...WILL NOT STICK TO THE GROUND. ESTIMATING HOW MUCH RAINFALL WILL RUN OFF VERSUS HOW MUCH WILL ACCUMULATE AS ICE IS EXTREMELY DIFFICULT. AT THIS TIME FORECAST ACCUMULATION AMOUNTS ARE APPROXIMATELY 25 PERCENT OF WHAT WE EXPECT TO FALL AS WATER EQUIVALENT PRECIPITATION. WHETHER THIS IS AGGRESSIVE OR CONSERVATIVE WILL DEPEND AT LEAST PARTIALLY ON HOW FAST WE FALL BELOW FREEZING BEHIND THE ARCTIC FRONT. FALLING BELOW FREEZING FASTER THAN EXPECTED WILL RESULT IN GREATER IMPACTS ON AVERAGE. WE WILL MONITOR THE PROGRESS OF THE FRONT THIS EVENING AND OVERNIGHT...AND IF IT LOOKS LIKE WE WILL GET COLDER SIGNIFICANTLY FASTER...WE MAY HAVE TO UPGRADE SOME PORTIONS OF THE ADVISORY INTO A WINTER STORM WARNING BEFORE SUNDAY MORNING. AT THIS TIME THE MOST LIKELY SCENARIO IS ICE ACCUMULATION AND IMPACTS MAINLY RELEGATED TO ELEVATED SURFACES...WHICH IS WHY A WINTER WEATHER ADVISORY IS IN EFFECT AND NOT A WINTER STORM WARNING AT THIS TIME. CURRENT THINKING IS THAT ONE TENTH TO ONE QUARTER OF AN INCH OF SLEET IS POSSIBLE ACROSS THE ADVISORY AREA...ALONG WITH LIGHT ICE ACCUMULATIONS OF LESS THAN ONE TENTH OF AN INCH...MAINLY ON ELEVATED SURFACES. WITH MOST ATTENTION FOCUSED ON SUNDAYS FRONT AND ASSOCIATED WINTER WEATHER...HERE IS A QUICK SUMMARY OF THE REMAINDER OF THE FORECAST: PRECIPITATION IS EXPECTED TO END FROM WEST TO EAST SUNDAY EVENING ACROSS NORTH TEXAS. TEMPERATURES WILL REMAIN BELOW FREEZING ALL NIGHT...MEANING ANY RESIDUAL WATER ON AREA ROADWAYS WILL FREEZE UP CAUSING ADDITIONAL TRAVEL PROBLEMS. MONDAY MORNING WIND CHILL VALUES WILL BE ZERO TO MINUS 5 DEGREES FOR MUCH OF NORTH TEXAS...ASSUMING THIS DOES NOT CHANGE IN FUTURE FORECASTS...WE WILL NEED A WIND CHILL ADVISORY FOR MUCH OF THE CWA EARLY MONDAY MORNING TO ACCOUNT FOR THESE VERY COLD WIND CHILL VALUES. WITH COLD AIR IN PLACE...WE HAVE A CHANCE FOR LIGHT FREEZING RAIN ACROSS CENTRAL TEXAS EARLY TUESDAY MORNING INTO THE LATE MORNING HOURS OF THE DAY. WE WILL NEED TO WATCH THIS NEXT UPPER LEVEL SYSTEM CLOSELY IN CASE IMPACTS ARE GREATER THAN CURRENTLY FORECAST. CURRENTLY...ANY ICE ACCUMULATIONS ARE EXPECTED TO REMAIN VERY LIGHT...ON THE ORDER OF ONE HUNDREDTH OF AN INCH. WE WILL WARM UP FOR THE REMAINDER OF THE WEEK...BUT HAVE LOW RAIN CHANCES IN THE FORECAST IN THE MIDDLE OF THE WEEK WITH YET ANOTHER UPPER LEVEL STORM SYSTEM PASSING OVER THE REGION. THIS PRECIPITATION IS EXPECTED TO REMAIN WARM ENOUGH FOR ALL RAIN AT THIS TIME. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 36 39 16 36 24 / 60 80 10 0 10 WACO, TX 59 63 20 41 29 / 20 80 10 0 10 PARIS, TX 35 38 11 34 22 / 60 90 30 0 10 DENTON, TX 32 33 14 34 21 / 60 80 10 0 10 MCKINNEY, TX 33 35 13 34 19 / 60 80 20 0 10 DALLAS, TX 38 41 16 37 25 / 50 80 10 0 10 TERRELL, TX 44 52 15 36 23 / 50 80 20 0 10 CORSICANA, TX 59 62 18 38 26 / 30 80 20 0 10 TEMPLE, TX 66 67 21 42 30 / 10 80 10 0 20 MINERAL WELLS, TX 32 33 14 36 23 / 50 80 10 0 10 && .FWD WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 6 AM TO 9 PM CST SUNDAY FOR TXZ091>095-100>107-115>123-129>135-144>146. && $$ /
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
346 PM CST SAT MAR 1 2014 .SHORT TERM... HARSH CHANGES AWAIT THE SOUTH PLAINS FOLLOWING OUR LATE SPRING-LIKE WARMTH OF TODAY. ONE NEED ONLY LOOK AT THE 21Z STATE TEMPS THAT RANGED FROM 91 IN BRADY TO JUST THE LOWER 20S IN PERRYTON...NOT FAR FROM SNOW ALREADY OBSERVED IN THE OK PANHANDLE! STATIONARY FRONT AT 21Z STRETCHED FROM HAPPY SOUTHEAST TO FLOYDADA AND JAYTON. 88D ALREADY SHOWS THIS FRONT EDGING SOUTHWESTWARD AND THIS TREND WILL ONLY ACCELERATE IN THE COMING HOURS AS AN AXIS OF ARCTIC HIGH PRESSURE BUILDS INTO THE ROLLING PLAINS. RUC HAS BEEN QUITE SOLID TODAY WITH THIS BOUNDARY AND INDICATES COLD FROPA AT LUBBOCK NEAR SUNSET. TEMPORARY DILUTION OF STRATUS NEAR CHILDRESS SHOULD RESUME IN THE COMING HOURS AND GRADUALLY EXPAND SWWD TONIGHT. BRUNT OF THE FORECAST CHALLENGE DOES NOT CONCERN THE FRONT...BUT RATHER AN AXIS OF SUBTROPICAL MOISTURE CURRENTLY STREAMING ACROSS SRN ARIZONA AND NEW MEXICO AHEAD OF A DECAYING UPPER LOW IN SRN CALIFORNIA. LATEST MODELS ARE HANDLING THIS MOISTURE RATHER WELL...BUT CONSIDERING THE PARENT LOW WILL BE DISSOLVING INTO AN OPEN WAVE AS IT MOVES EAST TONIGHT...THE QUESTION BECOMES HOW MUCH OF THIS RESIDUAL MOISTURE CAN TRANSLATE INTO PRECIP FOR OUR AREA? WE ARE NOT OVERLY EXCITED ABOUT PRECIP AMOUNTS IN THE SETUP...BUT DO ACKNOWLEDGE A WINDOW FROM 12Z TO 18Z WHEN BOTH LIFT AND DEEPENING SATURATION LOOK SUFFICIENT FOR LIGHT PRECIP. AS THE MID-LEVEL VORT MAX TRACKS ACROSS OUR WESTERN AND NWRN COUNTIES BY SUN AFTN...LIFT SHOULD BE BOLSTERED AS IT ENCOUNTERS ELEVATED FN FORCING TRAILING OUR SURFACE FRONT. GIVEN THE TRACK OF THE VORT MAX...OUR SERN COUNTIES LOOK TO MISS OUT ON THE BEST PRECIP CHANCES...SO POPS HAVE BEEN REDUCED HERE WHILE BUMPING UP TO LIKELY MENTION N-NW OF LUBBOCK. PRECIP PHASE IS THE NEXT CHALLENGE...BUT MODEL SOUNDINGS AS A WHOLE INSIST ON KEEPING SOME DEGREE OF A WARM NOSE PRESENT ALOFT WHICH WILL ACT TO SUSTAIN A WINTRY MIX LONGER THAN WE/D CARE TO SEE. WE DID SIDE A BIT COLDER THAN MODEL GUIDANCE WITH SURFACE WET BULB TEMPS THROUGH SUNDAY GIVEN THE NATURE OF THE AIRMASS INVOLVED...SO THIS RESULTS IN A BROADER COVERAGE OF LIGHT FREEZING RAIN/DRIZZLE AND SLEET. ALL SNOW MAY BE HARD TO COME BY SO LONG AS WE RETAIN SOME MELTING ALOFT. ALSO...THE WINDOW FOR FREEZING RAIN APPEARS TO BE SMALL AS THE COLD AIR WILL ONLY DEEPEN WITH TIME AND TIP THE SCALES IN FAVOR OF SLEET. GROUND TEMPS ARE NOT PARTICULARLY FAVORABLE FOR ICING...BUT THE BEST CHANCE FOR LIGHT ACCUMS OF SLEET AND A THIN GLAZE OF ICE ARE CURRENTLY FAVORED IN OUR NORTH AND NORTHWEST COUNTIES WHERE WE HAVE HOISTED A WINTER WX ADVISORY FOR SUNDAY. CLIMATOLOGY ALSO TENDS TO FAVOR THESE AREAS FOR WINTRY PRECIP IN THESE SITUATIONS...BUT LATER SHIFTS WILL MONITOR TRENDS AND ADJUST THE ADVISORY IF NEEDED. LASTLY...WE CONTINUED TO SCALE BACK MAX TEMPS FOR SUNDAY IN LIGHT OF ABUNDANT STRATUS AND DEEPENING COLD AIR ADVECTION. && .LONG TERM... AFTER A QUICK ROUND OF WINTRY WEATHER SUNDAY...THE REST OF THE FORECAST PERIOD LOOKS RELATIVELY BENIGN...ALTHOUGH THERE REMAINS A BIT OF UNCERTAINTY REGARDING THE DEVELOPMENT OF TWO SEPARATE STORM SYSTEMS BY THE MIDDLE AND END OF NEXT WEEK. BEGINNING TOMORROW EVENING...IT APPEARS THAT THE VAST MAJORITY OF PRECIPITATION WILL HAVE ENDED...HOWEVER THE COLD AIR WILL UNFORTUNATELY LINGER OVERNIGHT AND THROUGH THE DAY MONDAY. WHILE SOUTHERLY SURFACE WINDS WILL MAKE AN ATTEMPT AT RECOVERY ACROSS AT LEAST THE WESTERN SOUTH PLAINS MONDAY AFTERNOON... TEMPERATURES WILL LIKELY REMAIN WELL ABOVE NORMAL THROUGHOUT THE REGION...RANGING FROM THE UPPER 40S WEST...TO THE LOW 30S IN THE NORTHERN ROLLING PLAINS. SUBDUED...GRADUAL MODERATION WILL BEGIN TUESDAY UNDER A REGIME OF WEAK ZONAL FLOW ALOFT AND A MOSTLY DRY AIRMASS...WITH THE POSSIBLE EXCEPTION OF STUBBORN HIGH CIRRUS CLOUDS. FROM HERE...MODEL SOLUTIONS DIVERGE SIGNIFICANTLY WITH ITS RESPECTIVE SOLUTIONS. THE GFS MAINTAINS THE STATUS QUO...MORE OR LESS...BY SENDING A SERIES OF PROGRESSIVE OPEN SHORTWAVES ACROSS THE CENTRAL PLAINS. THIS PARTICULAR PATTERN WOULD LIKELY YIELD LITTLE MORE THAN DRY...MILD COLD FRONTS ACROSS WEST TEXAS...AND AS OF NOW IS THE PREFERRED SOLUTION GOING FORWARD. ON THE OTHER HAND... THE ECMWF IS MUCH DEEPER AND SLOWER IN ITS DEPICTION OF UPPER WAVES ON WEDNESDAY/THURSDAY AND AGAIN OVER THE WEEKEND. LIKEWISE...THIS DEPICTION WOULD RESULT IN MUCH GREATER CHANCES FOR PRECIPITATION IF IT WERE TO PAN OUT. FOR NOW THOUGH...THIS FORECAST WILL OPT TO SIDE WITH THE DRIER GFS UNTIL A BETTER CONSENSUS IS REACHED AMONG OPERATIONAL MODELS. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 33 33 16 48 26 / 30 60 0 0 0 TULIA 26 28 12 42 25 / 20 60 10 0 0 PLAINVIEW 27 30 12 43 25 / 10 60 0 0 0 LEVELLAND 34 34 18 45 26 / 10 60 0 0 0 LUBBOCK 29 31 15 43 25 / 10 50 0 0 0 DENVER CITY 38 46 19 48 27 / 10 40 0 0 0 BROWNFIELD 35 36 18 46 26 / 10 40 0 0 0 CHILDRESS 22 25 9 33 22 / 10 40 10 0 0 SPUR 27 29 11 38 23 / 10 30 0 0 0 ASPERMONT 29 29 10 38 23 / 20 20 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR THE FOLLOWING ZONES: TXZ021-022-027-028-033-034-039-040. WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR THE FOLLOWING ZONES: TXZ021>025-027>030. && $$ 93/16
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
534 AM CST SAT MAR 1 2014 .AVIATION... AN AREA OF LOW CIGS AND VISBYS WERE RAPIDLY APPROACHING KCDS. LOW VISIBILITIES ARE EXPECTED TO PERSIST FOR A FEW HOURS HOWEVER THE LOW CIGS ARE MORE UNCERTAIN. IT IS LIKELY THAT LOW CIGS WILL LAST AT LEAST THROUGH THE MORNING BUT THEIR RESIDENCE COULD BE EXTENDED WELL INTO THE AFTERNOON HOURS. AS THE LOW CLOUDS MOVE IN TO THE TERMINAL...THEY WILL LIKELY BE IFR OR EVEN LIFR. BY LATE IN THE MORNING AND INTO THE AFTERNOON THE CEILING HEIGHT IS ANTICIPATED TO RISE NEAR MVFR. SIMILAR TO YESTERDAY...STRONG WINDS WILL AFFECT KLBB WITH SOME POSSIBLE LIGHT VISIBILITY RESTRICTIONS DUE TO BLOWING DUST. A COLD FRONT WILL PUSH INTO THE REGION OVERNIGHT BRINGING ADDITIONAL LOW CIGS TO BOTH TERMINALS BY SUNDAY MORNING. && .PREV DISCUSSION... /ISSUED 453 AM CST SAT MAR 1 2014/ SHORT TERM... THIS FORECAST WAS COMPLICATED WITH A TOUGH ROW TO HOE. THE FIRST ISSUE TO DEAL WITH WAS THE FOG AND LOW STRATUS CLOSING IN ON THE AREA BOTH FROM THE EAST AND NORTH. THE LOW LEVEL MOISTURE WILL CONTINUE TO PROGRESS INTO THE ROLLING PLAINS ON THE EAST SIDE OF THE FRONTAL BOUNDARY THIS MORNING. THE FRONT WILL LIKELY MAKE ADDITIONAL PROGRESS WESTWARD EARLY THIS MORNING. THE FRONTAL POSITION WILL LIKELY BE A GOOD DIVIDING POINT BETWEEN CLEAR SKIES AND THE LOW STRATUS LAYER. THE CLOUDS THEN PRESENT A PROBLEM WITH THE TEMPERATURE FORECAST OVER THE SOUTHEASTERN TEXAS PANHANDLE. MOST GUIDANCE DEPICTS LOW STRATUS HANGING OUT FOR THE ENTIRE MORNING. IN FACT...THE LATEST RAP GUIDANCE SHOWS THIS LOW STRATUS CAMPING OUT NEAR CHILDRESS. THE LATER SITUATION WOULD CLEARLY KEEP TEMPERATURES FROM CLIMBING VERY MUCH AT CHILDRESS THIS AFTERNOON. THIS FRONTS WESTWARD PROGRESSION WILL BE HALTED BY A CLOSED LOW MOVING ONSHORE IN SOUTHERN CALIFORNIA TODAY. THIS WILL INCREASE SOUTHWEST FLOW ALOFT WITH THE FRONT RETREATING A BIT THIS AFTERNOON. SURFACE LEE TROUGHING WILL DEVELOP BY THIS AFTERNOON BUMPING UP WINDS INTO THE BREEZY CATEGORY AGAIN. WINDS ALOFT WILL BE MARKEDLY LOWER THAN OBSERVED YESTERDAY ALTHOUGH STILL BETWEEN 30 AND 40KT AT 700MB. HIGH CLOUDS MOVING IN FROM THE WEST MAY KEEP ATMOSPHERIC MIXING FROM REACHING ITS FULL POTENTIAL TODAY BUT IT WILL STILL NONETHELESS BE BREEZY. DOWNSLOPING WINDS COMBINED WITH STRONG LARGE SCALE SUBSIDENCE WILL LEAD TO SURFACE CONDITIONS LIKELY DRIER THAN WHAT MODELS ADVERTISE AS WAS THE CASE YESTERDAY. THE LOW LEVEL THERMAL RIDGE AXIS WILL INCREASE FROM THE TRANS PECOS EXTENDING INTO THE SOUTHWESTERN PANHANDLE. BY SUNDAY MORNING...THE SPRAWLING HIGH PRESSURE OVER THE PLAINS WILL BEGIN TO EXERT INFLUENCE OVER WEST TEXAS AS THE COLD FRONT PUSHES FARTHER WEST. LARGE SCALE LIFT WILL INCREASE OVER THE AREA BY SUNDAY MORNING WITH A 110KT UPPER LEVEL JET MOVING OVERHEAD. NEAR SURFACE CONDITIONS WILL SEE A MASHUP OF BOTH THE ARCTIC FRONT AND PACIFIC FRONT MAKING ITS WAY THROUGH THE WEST. THIS WILL CREATE CLEARLY DEFINED AREAS OF FRONTOGENETICAL FORCING. PRECIPITATION CHANCES WILL INCREASE AFTER MIDNIGHT WITH STRONGER LOW LEVEL MOISTURE ADVECTING INTO THE REGION BEHIND THE COLD FRONT. MID AND UPPER LEVELS WILL BE FAIRLY SATURATED WITH PACIFIC MOISTURE AS THE UPPER LOW IN THE SOUTHWEST EDGES CLOSER. AREAS TO THE WEST OF THE FRONT WILL LIKELY STAY WARM ENOUGH FOR ALL LIQUID PRECIPITATION. ON THE EAST SIDE OF THE FRONT...COOLER AIR ADVECTING INTO THE REGION AT THE LOWEST LEVELS WILL CHANGE PRECIPITATION TYPE TO MOST LIKELY A MIX OF FREEZING RAIN AND SLEET. THE LOWEST TEMPERATURE IN THE NEAR SURFACE SUB FREEZING LAYER APPROACHES AND MAY EXCEED -10C. IN CONTRAST...EAST OF THE AREA...STRONG ISENTROPIC LIFT ABOVE THE FRONTAL BOUNDARY WILL CREATE CHANCES OF PRECIPITATION. ALTHOUGH THE BEST CHANCES WILL REMAIN EAST...THERE WILL ALSO EXIST A POTENTIAL FOR A RUMBLE OF THUNDER WITH IMPRESSIVE ELEVATED INSTABILITY. LONG TERM... QUITE AN IMPRESSIVE UPPER LEVEL STORM SYSTEM ALONG THE CALIFORNIA CENTRAL COAST WILL EJECT EASTWARD ACROSS THE SOUTHERN ROCKIES LATE TONIGHT THEN THE SOUTHERN HIGH PLAINS ON SUNDAY. A GLACIAL AIRMASS MEANWHILE WILL PRESS SOUTHWARD OUT OF THE NORTHERN PLAINS AND COULD BE POISED TO SWEEP OVER THE AREA SUNDAY. THE RATE OF DECAY OF THE CALIFORNIA SYSTEM WILL BE KEY IN DE TERMING EVERY ASPECT OF WEATHER FOR SUNDAY. AND EVEN THOUGH SOLUTIONS SEEM SIMILAR ALOFT IN THIS ASPECT THEY TOY WITH US IN A VARIETY OF MANNERS REGARDING FRONTAL MOVEMENT...THERMAL CONTOURING...PRECIPITATION AREAS... AMOUNTS...AND TYPES. OUR AREA SEEMS TO BE GROUND ZERO FOR THE MODEL DISSENT GIVING RISE TO ANY NUMBER OF OUTCOMES SUNDAY RANGING FROM FIRE WEATHER CONDITIONS IN THE SOUTHWESTERN SOUTH PLAINS...SNOW AND ICE ACCUMULATIONS IN THE NORTH-CENTRAL...FOG AND FREEZING DRIZZLE FOR THE EAST-NORTHEAST...AND MAYBE EVEN A RUMBLE OF THUNDER HERE AND THERE. AND OF COURSE PRECIPITATION COULD TOTALLY DISAPPOINT SHOULD THE SYSTEM PASSING ALOFT REMAIN TOO WEAK OR IF VERY DRY AIR DOMINATES THE LOWER ATMOSPHERE. THIS COMPLEX AND LOW CONFIDENCE ENVIRONMENT LENDS ITSELF TO A SOMEWHAT SIMPLIFIED FORECAST. IN PARTICULAR WE BLENDED THE WRF/NAM AND GFS PRECIPITATION COVERAGE ON SUNDAY WHICH GAVE FAIRLY UNIFORM CHANCE CATEGORY ACROSS THE AREA. THEN...WE SIDED WITH THE MOST RECENT BLEND OF FRONTAL POSITIONS FAVORING THE FRONT STRUGGLING TO MANEUVER THROUGH THE INCREASED WESTERLY COMPONENTS EXPECTED EARLY SUNDAY ACROSS THE WESTERN SOUTH PLAINS. THIS FORCED US TO ADJUST THE FRONT A BIT TO THE EAST WITH 35 DEGREE TEMPERATURE GRADIENT SOUTHWEST TO NORTHEAST. ALSO...WE CONSIDERED POTENTIAL LIFT FROM A SLOPED FRONTAL BOUNDARY FOR LOCAL SIGNIFICANT TOTALS SHOULD SYSTEM REMAIN SLIGHTLY MORE VIGOROUS. BUT OUR CONFIDENCE IN PINPOINTING THESE AREAS WAS LOW. SO WE ALSO SIMPLIFIED POTENTIAL PRECIPITATION AMOUNTS AND TYPES FAVORING GENERALLY WARM PHASE SOUTHWEST...FREEZING EAST...AND CHANGE TO FROZEN NORTH. THIS SYSTEM WILL EJECT BY LATE SUNDAY WITH NO MAJOR CHANGES FOR THE WEEK AHEAD. VERY COLD DUMP LASTING INTO EARLY TUESDAY WITH SLOW MODERATION BEYOND. GENERAL FLAT PATTERN ALOFT ALTHOUGH A FEW WAVES PASSING EARLY TO MID WEEK MAY NEED CONSIDERATION OF PRECIPITATION CHANCES DEPENDING ON DEPTH OF THE LINGERING COLD AIR... ALTHOUGH DRY AIR STILL LOOKS TO REMAIN DOMINANT. RMCQUEEN FIRE WEATHER... CRITICAL FIRE WEATHER CONDITIONS APPEAR TO BE LIKELY OVER THE SOUTHWESTERN SOUTH PLAINS THIS AFTERNOON. STRONG SOUTHWESTERLY SURFACE WINDS WILL DEVELOP IN RESPONSE TO AN UPPER LEVEL LOW MOVING ONSHORE INTO THE DESERT SOUTHWEST. ADDITIONALLY...DEEP ATMOSPHERIC MIXING WILL BRING STRONG WINDS ALOFT DOWN TO THE SURFACE. THESE STRONG SOUTHWESTERLY WINDS WILL BUMP UP TEMPERATURES WELL ABOVE SEASONAL AVERAGES WITH AFTERNOON TEMPERATURES AROUND 80F. VERY DRY AIR WILL STAY IN PLACE WHICH WILL RESULT IN AFTERNOON RELATIVE HUMIDITY VALUES AROUND 10 PERCENT. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 75 36 36 15 47 / 0 30 40 10 0 TULIA 73 26 30 13 40 / 0 20 30 10 0 PLAINVIEW 76 29 33 13 41 / 0 10 30 10 0 LEVELLAND 80 39 50 17 45 / 0 10 30 10 0 LUBBOCK 82 36 44 16 42 / 0 10 30 10 0 DENVER CITY 79 40 58 19 46 / 0 10 30 0 0 BROWNFIELD 81 39 53 17 44 / 0 10 30 10 0 CHILDRESS 61 24 26 11 32 / 0 20 30 0 0 SPUR 80 28 32 14 36 / 0 10 30 10 0 ASPERMONT 84 28 30 13 36 / 0 20 30 10 0 && .LUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 11 AM THIS MORNING TO 6 PM CST THIS EVENING FOR THE FOLLOWING ZONES: TXZ027-033-034-039-040. && $$ 01
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
453 AM CST SAT MAR 1 2014 .SHORT TERM... THIS FORECAST WAS COMPLICATED WITH A TOUGH ROW TO HOE. THE FIRST ISSUE TO DEAL WITH WAS THE FOG AND LOW STRATUS CLOSING IN ON THE AREA BOTH FROM THE EAST AND NORTH. THE LOW LEVEL MOISTURE WILL CONTINUE TO PROGRESS INTO THE ROLLING PLAINS ON THE EAST SIDE OF THE FRONTAL BOUNDARY THIS MORNING. THE FRONT WILL LIKELY MAKE ADDITIONAL PROGRESS WESTWARD EARLY THIS MORNING. THE FRONTAL POSITION WILL LIKELY BE A GOOD DIVIDING POINT BETWEEN CLEAR SKIES AND THE LOW STRATUS LAYER. THE CLOUDS THEN PRESENT A PROBLEM WITH THE TEMPERATURE FORECAST OVER THE SOUTHEASTERN TEXAS PANHANDLE. MOST GUIDANCE DEPICTS LOW STRATUS HANGING OUT FOR THE ENTIRE MORNING. IN FACT...THE LATEST RAP GUIDANCE SHOWS THIS LOW STRATUS CAMPING OUT NEAR CHILDRESS. THE LATER SITUATION WOULD CLEARLY KEEP TEMPERATURES FROM CLIMBING VERY MUCH AT CHILDRESS THIS AFTERNOON. THIS FRONTS WESTWARD PROGRESSION WILL BE HALTED BY A CLOSED LOW MOVING ONSHORE IN SOUTHERN CALIFORNIA TODAY. THIS WILL INCREASE SOUTHWEST FLOW ALOFT WITH THE FRONT RETREATING A BIT THIS AFTERNOON. SURFACE LEE TROUGHING WILL DEVELOP BY THIS AFTERNOON BUMPING UP WINDS INTO THE BREEZY CATEGORY AGAIN. WINDS ALOFT WILL BE MARKEDLY LOWER THAN OBSERVED YESTERDAY ALTHOUGH STILL BETWEEN 30 AND 40KT AT 700MB. HIGH CLOUDS MOVING IN FROM THE WEST MAY KEEP ATMOSPHERIC MIXING FROM REACHING ITS FULL POTENTIAL TODAY BUT IT WILL STILL NONETHELESS BE BREEZY. DOWNSLOPING WINDS COMBINED WITH STRONG LARGE SCALE SUBSIDENCE WILL LEAD TO SURFACE CONDITIONS LIKELY DRIER THAN WHAT MODELS ADVERTISE AS WAS THE CASE YESTERDAY. THE LOW LEVEL THERMAL RIDGE AXIS WILL INCREASE FROM THE TRANS PECOS EXTENDING INTO THE SOUTHWESTERN PANHANDLE. BY SUNDAY MORNING...THE SPRAWLING HIGH PRESSURE OVER THE PLAINS WILL BEGIN TO EXERT INFLUENCE OVER WEST TEXAS AS THE COLD FRONT PUSHES FARTHER WEST. LARGE SCALE LIFT WILL INCREASE OVER THE AREA BY SUNDAY MORNING WITH A 110KT UPPER LEVEL JET MOVING OVERHEAD. NEAR SURFACE CONDITIONS WILL SEE A MASHUP OF BOTH THE ARCTIC FRONT AND PACIFIC FRONT MAKING ITS WAY THROUGH THE WEST. THIS WILL CREATE CLEARLY DEFINED AREAS OF FRONTOGENETICAL FORCING. PRECIPITATION CHANCES WILL INCREASE AFTER MIDNIGHT WITH STRONGER LOW LEVEL MOISTURE ADVECTING INTO THE REGION BEHIND THE COLD FRONT. MID AND UPPER LEVELS WILL BE FAIRLY SATURATED WITH PACIFIC MOISTURE AS THE UPPER LOW IN THE SOUTHWEST EDGES CLOSER. AREAS TO THE WEST OF THE FRONT WILL LIKELY STAY WARM ENOUGH FOR ALL LIQUID PRECIPITATION. ON THE EAST SIDE OF THE FRONT...COOLER AIR ADVECTING INTO THE REGION AT THE LOWEST LEVELS WILL CHANGE PRECIPITATION TYPE TO MOST LIKELY A MIX OF FREEZING RAIN AND SLEET. THE LOWEST TEMPERATURE IN THE NEAR SURFACE SUB FREEZING LAYER APPROACHES AND MAY EXCEED -10C. IN CONTRAST...EAST OF THE AREA...STRONG ISENTROPIC LIFT ABOVE THE FRONTAL BOUNDARY WILL CREATE CHANCES OF PRECIPITATION. ALTHOUGH THE BEST CHANCES WILL REMAIN EAST...THERE WILL ALSO EXIST A POTENTIAL FOR A RUMBLE OF THUNDER WITH IMPRESSIVE ELEVATED INSTABILITY. && .LONG TERM... QUITE AN IMPRESSIVE UPPER LEVEL STORM SYSTEM ALONG THE CALIFORNIA CENTRAL COAST WILL EJECT EASTWARD ACROSS THE SOUTHERN ROCKIES LATE TONIGHT THEN THE SOUTHERN HIGH PLAINS ON SUNDAY. A GLACIAL AIRMASS MEANWHILE WILL PRESS SOUTHWARD OUT OF THE NORTHERN PLAINS AND COULD BE POISED TO SWEEP OVER THE AREA SUNDAY. THE RATE OF DECAY OF THE CALIFORNIA SYSTEM WILL BE KEY IN DE TERMING EVERY ASPECT OF WEATHER FOR SUNDAY. AND EVEN THOUGH SOLUTIONS SEEM SIMILAR ALOFT IN THIS ASPECT THEY TOY WITH US IN A VARIETY OF MANNERS REGARDING FRONTAL MOVEMENT...THERMAL CONTOURING...PRECIPITATION AREAS... AMOUNTS...AND TYPES. OUR AREA SEEMS TO BE GROUND ZERO FOR THE MODEL DISSENT GIVING RISE TO ANY NUMBER OF OUTCOMES SUNDAY RANGING FROM FIRE WEATHER CONDITIONS IN THE SOUTHWESTERN SOUTH PLAINS...SNOW AND ICE ACCUMULATIONS IN THE NORTH-CENTRAL...FOG AND FREEZING DRIZZLE FOR THE EAST-NORTHEAST...AND MAYBE EVEN A RUMBLE OF THUNDER HERE AND THERE. AND OF COURSE PRECIPITATION COULD TOTALLY DISAPPOINT SHOULD THE SYSTEM PASSING ALOFT REMAIN TOO WEAK OR IF VERY DRY AIR DOMINATES THE LOWER ATMOSPHERE. THIS COMPLEX AND LOW CONFIDENCE ENVIRONMENT LENDS ITSELF TO A SOMEWHAT SIMPLIFIED FORECAST. IN PARTICULAR WE BLENDED THE WRF/NAM AND GFS PRECIPITATION COVERAGE ON SUNDAY WHICH GAVE FAIRLY UNIFORM CHANCE CATEGORY ACROSS THE AREA. THEN...WE SIDED WITH THE MOST RECENT BLEND OF FRONTAL POSITIONS FAVORING THE FRONT STRUGGLING TO MANEUVER THROUGH THE INCREASED WESTERLY COMPONENTS EXPECTED EARLY SUNDAY ACROSS THE WESTERN SOUTH PLAINS. THIS FORCED US TO ADJUST THE FRONT A BIT TO THE EAST WITH 35 DEGREE TEMPERATURE GRADIENT SOUTHWEST TO NORTHEAST. ALSO...WE CONSIDERED POTENTIAL LIFT FROM A SLOPED FRONTAL BOUNDARY FOR LOCAL SIGNIFICANT TOTALS SHOULD SYSTEM REMAIN SLIGHTLY MORE VIGOROUS. BUT OUR CONFIDENCE IN PINPOINTING THESE AREAS WAS LOW. SO WE ALSO SIMPLIFIED POTENTIAL PRECIPITATION AMOUNTS AND TYPES FAVORING GENERALLY WARM PHASE SOUTHWEST...FREEZING EAST...AND CHANGE TO FROZEN NORTH. THIS SYSTEM WILL EJECT BY LATE SUNDAY WITH NO MAJOR CHANGES FOR THE WEEK AHEAD. VERY COLD DUMP LASTING INTO EARLY TUESDAY WITH SLOW MODERATION BEYOND. GENERAL FLAT PATTERN ALOFT ALTHOUGH A FEW WAVES PASSING EARLY TO MID WEEK MAY NEED CONSIDERATION OF PRECIPITATION CHANCES DEPENDING ON DEPTH OF THE LINGERING COLD AIR... ALTHOUGH DRY AIR STILL LOOKS TO REMAIN DOMINANT. RMCQUEEN && .FIRE WEATHER... CRITICAL FIRE WEATHER CONDITIONS APPEAR TO BE LIKELY OVER THE SOUTHWESTERN SOUTH PLAINS THIS AFTERNOON. STRONG SOUTHWESTERLY SURFACE WINDS WILL DEVELOP IN RESPONSE TO AN UPPER LEVEL LOW MOVING ONSHORE INTO THE DESERT SOUTHWEST. ADDITIONALLY...DEEP ATMOSPHERIC MIXING WILL BRING STRONG WINDS ALOFT DOWN TO THE SURFACE. THESE STRONG SOUTHWESTERLY WINDS WILL BUMP UP TEMPERATURES WELL ABOVE SEASONAL AVERAGES WITH AFTERNOON TEMPERATURES AROUND 80F. VERY DRY AIR WILL STAY IN PLACE WHICH WILL RESULT IN AFTERNOON RELATIVE HUMIDITY VALUES AROUND 10 PERCENT. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 75 36 36 15 47 / 0 30 40 10 0 TULIA 73 26 30 13 40 / 0 20 30 10 0 PLAINVIEW 76 29 33 13 41 / 0 10 30 10 0 LEVELLAND 80 39 50 17 45 / 0 10 30 10 0 LUBBOCK 82 36 46 16 42 / 0 10 30 10 0 DENVER CITY 79 40 58 19 46 / 0 10 30 0 0 BROWNFIELD 81 39 53 17 44 / 0 10 30 10 0 CHILDRESS 63 24 26 11 32 / 0 20 30 0 0 SPUR 80 28 32 14 36 / 0 10 30 10 0 ASPERMONT 84 28 30 13 36 / 0 20 30 10 0 && .LUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM 11 AM THIS MORNING TO 6 PM CST THIS EVENING FOR THE FOLLOWING ZONES: TXZ027-033-034-039-040. && $$ 01/05
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1156 PM CST FRI FEB 28 2014 .AVIATION... 06Z TAFS...A COLD FRONT WILL CONTINUE TO BACK SOUTHWEST ACROSS THE PANHANDLES TONIGHT...WITH LOW CLOUDS AND FOG DEVELOPING BEHIND IT. LOW CLOUDS ARE ALREADY NEARING KGUY...AND IFR CIGS ARE EXPECTED TO FILL IN AT KGUY OVERNIGHT AND LAST INTO LATE SATURDAY MORNING. CONDITIONS ARE EXPECTED TO IMPROVE TO MVFR AND VFR FOR A TIME AT KGUY LATE SATURDAY MORNING AND SATURDAY AFTERNOON...BEFORE QUICKLY DETERIORATING AGAIN EARLY SATURDAY EVENING AS CIGS FALL AND PRECIPITATION DEVELOPS...LIKELY IN THE FORM OF -FZRA. FOR KAMA AND KDHT...CONFIDENCE IS LOWER REGARDING HOW FAR SOUTH AND WEST THE LOW CLOUDS AND FOG WILL MAKE IT OVERNIGHT. DO THINK THE LOW CLOUDS WILL MAKE IT INTO KDHT AND HAVE INTRODUCED SOME IFR CONDITIONS ACCORDINGLY. KAMA LOOKS TO BE RIGHT ON THE EDGE WITH SOME VERY SHALLOW MOISTENING DEPICTED IN FORECAST SOUNDINGS. THUS HAVE INTRODUCED SOME MVFR VSBYS WITH FOG...BUT CONDITIONS COULD CERTAINLY GO LOWER THAN THIS IN THE 11-15Z TIMEFRAME. INCREASING SOUTH/SOUTHWEST WINDS SHOULD SCOUR OUT ANY LOW CLOUDS/FOG AT KAMA AND KDHT BY LATE SATURDAY MORNING WITH VFR CONDITIONS THEN EXPECTED THROUGH THE AFTERNOON. MID-LEVEL CLOUDS WILL THICKEN SUNDAY EVENING...WITH SOME -RA POSSIBLE. KB && .PREV DISCUSSION... /ISSUED 939 PM CST FRI FEB 28 2014/ UPDATE... ADDED FOG TO THE FORECAST FOR LATE TONIGHT INTO SATURDAY MORNING ACROSS ALL BUT THE FAR SOUTHWEST TX PANHANDLE. LOW-LEVEL EASTERLY UPSLOPE FLOW APPEARS CONDUCIVE TO FOG DEVELOPMENT...AND MODEL LOW-LEVEL RH PROGS...SREF VSBY PROBS...AND HRRR VSBY PROGS ALL SUPPORT THIS. MAY SEE A FETCH OF LOWER SFC DEWPOINTS WORK INTO THE CENTRAL AND EASTERN OK PANHANDLE...LIMITING THE FOG THREAT AND SUPPORTING MORE OF A LOW CLOUD SCENARIO IN THESE AREAS /AND STILL CANNOT RULE OUT SOME PATCHY DZ OR FZDZ TOWARD DAYBREAK IF THE LOW-LEVEL MOIST LAYER DEEPENS ENOUGH IN THIS FAR NORTHEAST PORTION OF THE CWA/. FARTHER SOUTH HOWEVER...FOG LOOKS LIKE A BETTER BET ACROSS ALL BUT THE FAR SOUTHWEST TX PANHANDLE. TEMPS ARE EXPECTED TO FALL A LITTLE BELOW FREEZING ACROSS THE NORTHERN PANHANDLES...BUT WARM GROUND TEMPS FROM THE RECENT WARM STRETCH SHOULD PREVENT ANY REAL ICING PROBLEMS ON ROADWAYS. NOT TO MENTION...THE GREATER PROBABILITIES OF DENSER FOG APPEAR TO BE FARTHER SOUTH WHERE TEMPS WILL BE MAINLY ABOVE FREEZING. KB PREV DISCUSSION... /ISSUED 401 PM CST FRI FEB 28 2014/ SHORT TERM... THROUGH TONIGHT: AN ARCTIC FRONT WILL OOZE ITS WAY INTO THE PANHANDLES LATE TONIGHT BEFORE STALLING. BEHIND THE FRONT, LOW CLOUDS WILL RAPIDLY DEVELOP, ESPECIALLY ACROSS THE NORTHERN AND EASTERN PANHANDLES. ISENTROPIC ASCENT MAY DEEPEN LOW-LEVEL MOISTURE JUST ENOUGH TO WARRANT A MENTION OF PATCHY DRIZZLE/FREEZING DRIZZLE DEPENDING ON SURFACE TEMPERATURES. IF THE DRIZZLE IS IN THE FROZEN FORM, IT SHOULDN`T CAUSE ANY TRAVEL PROBLEMS AS GROUND TEMPERATURES HAVE BEEN RATHER WARM LATELY. NONETHELESS, IT COULD STICK TO ELEVATED AND METAL SURFACES. SATURDAY-SUNDAY NIGHT: THE ARCTIC FRONT WILL PLAY HAVOC WITH TEMPERATURES TOMORROW, AND WE`RE A LITTLE CONCERNED THE FRONT COULD SEEP FARTHER SOUTH AND WEST THAN WE`RE CURRENTLY FORECASTING. LIKE THE PREVIOUS SHIFT MENTIONED, IF THIS SCENARIO OCCURS, HIGH TEMPERATURES WILL BE FAR TOO WARM OVER THE SOUTHWEST HALF OF THE FORECAST AREA. THE THERMAL GRADIENT WILL BE VERY IMPRESSIVE ALONG THE FRONT SUCH THAT TEMPERATURES MAY VARY BY NEARLY 40 DEGREES WITHIN A 50-MILE DISTANCE. LARGE SCALE FORCING FOR ASCENT WILL GRADUALLY BEGIN INCREASING TOMORROW AFTERNOON FROM WEST TO EAST. EXPECT TO SEE SOME HIGH-BASED SHOWERS, POSSIBLY EVEN A THUNDERSTORM, MOVE OUT OF NORTHEAST NEW MEXICO INTO OUR NORTHWEST AREAS AFTER 2 PM. THESE HIGH-BASED SHOWERS COULD PRODUCE LOCALLY GUSTY WINDS UP TO 45 MPH BENEATH THEM, BUT NO SEVERE WEATHER IS EXPECTED. BY SATURDAY NIGHT AND SUNDAY MORNING, FORCING FOR ASCENT STRENGTHENS WITH THE APPROACH OF THE MAIN UPPER TROUGH. AS THE COLD FRONT SETTLES SOUTHWARD, ARCTIC AIR WILL GRADUALLY DEEPEN WITH TIME FROM NORTHEAST TO SOUTHWEST. AS THIS OCCURS IN CONJUNCTION WITH THE UPPER FORCING, PRECIPITATION WILL INCREASE IN COVERAGE, ESPECIALLY FOR LOCATIONS NORTH AND WEST OF THE HIGHWAY 60 CORRIDOR. PRECIPITATION TYPE IS VERY DIFFICULT AS THE NAM REMAINS THE FASTEST AND DEEPEST WITH THE ARCTIC AIR. IN FACT, IF THE NAM IS CORRECT, SNOW WILL BE THE PREDOMINANT TYPE OF PRECIPITATION AS THE BOUNDARY LAYER ESSENTIALLY BECOMES THE DENDRITIC GROWTH ZONE, ESPECIALLY LATE SATURDAY NIGHT AND SUNDAY. HOWEVER, ALL OTHER MODELS ARE NOT AS DEEP AND FAST WITH THE COLD AIR, MAKING FOR A MESSY PRECIPITATION TYPE FORECAST. AS A RESULT, WE THINK WE`LL INITIALLY SEE RAIN CHANGE TO FREEZING RAIN AND THEN FINE SNOW GRAINS AS THE COLD AIR DEEPENS. ACROSS THE SOUTHWESTERN TEXAS PANHANDLE, FREEZING RAIN AND RAIN WILL BE THE PREDOMINANT PRECIPITATION TYPES. THE PRECIPITATION TYPE WILL BECOME PREDOMINANTLY SNOW FOR THE SOUTHWEST TEXAS PANHANDLE AS THE ARCTIC AIR MASS BECOMES FULLY ENTRENCHED, BUT A BRIEF PERIOD OF SLEET CAN`T BE RULED OUT SUNDAY MORNING. THE PRECIPITATION IS EXPECTED TO BEGIN TAPERING OFF FROM WEST TO EAST LATE SUNDAY AFTERNOON. VERY COLD TEMPERATURES ARE EXPECTED ON SUNDAY WITH HIGHS RANGING FROM NEAR 40 IN THE SOUTHWEST (NEAR SUNRISE) TO THE MID TEENS IN THE NORTHEAST. THE HIGHEST SNOWFALL AMOUNTS ARE EXPECTED TO OCCUR ACROSS THE NORTHERN HALF OF THE PANHANDLES WHERE 1 TO 3 INCHES OF SNOW MAY OCCUR. ICE ACCUMULATIONS FROM FREEZING RAIN WILL MAINLY IMPACT THE TEXAS PANHANDLE WITH AMOUNTS EXPECTED TO REMAIN LESS THAN 0.10 OF AN INCH. HOWEVER, A WINTER WEATHER ADVISORY WILL LIKELY BE REQUIRED FOR PART OR ALL OF THE AREA SATURDAY NIGHT AND SUNDAY. BLOWING SNOW COULD ALSO LEAD TO REDUCED VISIBILITIES AND SOME DRIFTING. LONG TERM... THE GFS IS DEPICTING SOME POSSIBILITY OF LOCALIZED FREEZING FOG/FREEZING DRIZZLE ACROSS THE EASTERN OKLAHOMA AND NORTHEASTERN TEXAS PANHANDLES EARLY MONDAY MORNING, BUT CONFIDENCE REMAINS A LITTLE LOW TO INSERT INTO THE FORECAST CURRENTLY. MONDAY NIGHT A WEAK SHORTWAVE IS DEPICTED TO MOVE ACROSS THE PANHANDLES. MODELS AGREE THAT THIS SHORTWAVE SHOULD MOVE THROUGH DRY AS LOW LEVEL MOISTURE WILL BE LIMITED. HOWEVER SOME PRECIP MAY BE POSSIBLE A BIT NORTH OF THE OKLAHOMA PANHANDLE WHERE THE FORCING FROM THE SHORTWAVE AND THE ENTRANCE REGION OF THE SPLIT FLOW JET OVERLAP. ZONAL FLOW ALOFT WILL IS EXPECTED TO PREVAIL TUESDAY AND MOST OF WEDNESDAY. WEDNESDAY NIGHT A BROAD TROUGH WILL DROP ACROSS THE PANHANDLES. MEDIUM RANGE MODELS DISAGREE ON WHERE THERE WILL BE SUFFICIENT DYNAMICS AND MOISTURE FOR PRECIP TO OCCUR. THE ECMWF IS MORE FAVORABLE FOR PRECIP WHILE THE GFS IS A LITTLE LESS FAVORABLE. THE FORECAST LEANS CLOSER TO THE DRY GFS. NORTHERLY TO NORTHWESTERLY FLOW ALOFT IS EXPECTED FOR THURSDAY WHICH WILL ALLOW TEMPERATURES TO WARM NICELY BACK INTO THE MID TO UPPER 60S. PREVIOUS MODEL RUNS HINTED AT SOME PRECIP CHANCES FOR FRIDAY BUT THESE CHANCES HAVE BEEN PUSHED BACK TO FRIDAY NIGHT FOR THE GFS AND INTO SATURDAY FOR THE ECMWF. FIRE WEATHER... ELEVATED FIRE WEATHER CONDITIONS WILL BE POSSIBLE ACROSS THE SOUTHWESTERN TEXAS PANHANDLE SATURDAY AFTERNOON AS RELATIVE HUMIDITIES DROP TO 18 TO 20 PERCENT. TWENTY FOOT WINDS ARE EXPECTED TO INCREASE INTO THE 17 TO 25 MPH RANGE BY THE EARLY AFTERNOON FROM A SOUTHERLY TO SOUTH-SOUTHWESTERLY DIRECTION. FROM SATURDAY NIGHT THROUGH WEDNESDAY OF THIS COMING WEEK...NEITHER ELEVATED NOR CRITICAL FIRE WEATHER CONDITIONS ARE ANTICIPATED AT THIS TIME. ELEVATED FIRE WEATHER WILL BE POSSIBLE THURSDAY AFTERNOON ACROSS THE WESTERN AND CENTRAL PORTIONS OF THE TEXAS AND OKLAHOMA PANHANDLES. && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1148 PM CST FRI FEB 28 2014 .AVIATION... A FRONT HAS SAGGED THROUGH KCDS WITH LIGHT EASTERLY WINDS IN ITS WAKE. THIS FRONT MAY MAKE IT ALL THE WAY TO KLBB TOWARD 11-12Z. CONDITIONS SHOULD STAY VFR AT KLBB...BUT KCDS IS LIKELY TO SEE LOW CLOUDS AND FOG DEVELOP AROUND THIS SAME TIME...WITH IFR TO LIFR CONDITIONS POSSIBLE. THESE SUB-VFR CONDITIONS WILL LIKELY PERSIST AT KCDS THROUGH MUCH OF THE MORNING BEFORE THE CLOUDS/FOG LIFT/SCATTER AND VFR CONDITIONS RETURN DURING THE AFTERNOON HOURS. HOWEVER...CIGS WILL LIKELY REDEVELOP SATURDAY EVENING BEHIND A STRONGER FRONTAL SURGE. KLBB WILL LIKELY REMAIN VFR THROUGH THE TAF CYCLE...BUT WILL SEE GUSTY SOUTHWESTERLY WINDS MATERIALIZE DURING THE AFTERNOON HOURS BEFORE DECREASING IN THE EVENING. && .PREV DISCUSSION... /ISSUED 1009 PM CST FRI FEB 28 2014/ UPDATE... A WEAK FRONT IS IN THE PROCESS OF BACK-DOORING INTO THE AREA FROM THE NORTHEAST...WITH CHILDRESS AND NORTHFIELD ALREADY EXPERIENCING LIGHT EASTERLY BREEZES. THIS FRONT WILL CONTINUE ON ITS SOUTHWESTWARD PUSH THROUGH THE OVERNIGHT HOURS UNTIL STALLING OVER THE CENTRAL SOUTH PLAINS SATURDAY MORNING...THEN RETREATING SATURDAY AFTERNOON. BEHIND THE FRONT...LIGHT EASTERLY WINDS WILL CONTINUE TO TAP INCREASING AMOUNTS OF MOISTURE ALONG THE RED RIVER VALLEY. AS TEMPERATURES CONTINUE TO FALL AND LOW-LEVEL MOISTURE INCREASES...THE PROSPECTS FOR FOG AND LOW CLOUDS WILL INCREASE ACROSS THE EASTERN ZONES...LIKELY AFTER 09Z. THIS LOW CLOUD AND FOG DECK COULD ADVANCE AS FAR WESTWARD AS ROUGHLY A DIMMITT TO PLAINVIEW TO ASPERMONT LINE BY MID-MORNING BEFORE THINNING...LIFTING AND SCATTERING OUT. GIVEN THIS...WE HAVE UPDATED THE FORECAST TO INCLUDE AREAS OF FOG ACROSS ROUGHLY THE NORTHEAST HALF OF THE CWA IN THE 09-16Z TIME-FRAME. EARLY ON...SKY GRIDS WERE DECREASED GIVEN THE MOSTLY CLEAR SKIES CURRENTLY IN PLACE...BUT WERE BOOSTED ACROSS THE NORTHEAST ZONES AFTER 09Z AS THE LOW CLOUDS AND FOG ARE EXPECTED TO FILL IN. ASIDE FROM THE WEATHER AND SKY GRIDS...MINOR ADJUSTMENTS WERE ALSO MADE TO THE TEMPERATURE...DEWPOINT AND RH GRIDS. THE UPGRADED PRODUCTS HAVE BEEN SENT. PREV DISCUSSION... /ISSUED 556 PM CST FRI FEB 28 2014/ UPDATE... WINDS CONTINUE TO GRADUALLY DECREASE EARLY THIS EVENING BRINGING AN END TO THE CRITICAL FIRE WEATHER CONDITIONS FOR THE SOUTH PLAINS REGION. THUS...THE RED FLAG WARNING WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 00Z. PREV DISCUSSION... /ISSUED 348 PM CST FRI FEB 28 2014/ SHORT TERM... FOLLOWING A COMPACT S/W TROUGH THAT GENERATED TSTORMS IN PARTS OF THE TX PANHANDLE LAST NIGHT...THE AXIS OF STRONG WESTERLY WINDS HAVE SINCE EXITED THE FORECAST AREA ON SCHEDULE. THESE WINDS DID RESULT IN A BIT MORE DRAMA THAN EXPECTED THANKS TO A 59 MPH GUST AS MEASURED BY THE GRAHAM WEST TX MESONET...BUT AS A WHOLE THE BLOWING DUST THIS MORNING WAS NOTHING UNUSUAL FOR THE HARDY RESIDENTS THAT FREQUENT THESE PARTS. ALREADY BY SUNSET...A WEAK COLD FRONT WILL BE EDGING SOUTHWEST ACROSS THE EASTERN PANHANDLE WELL AHEAD OF A BROODING ARCTIC HIGH STILL POISED IN THE WESTERN CANADIAN PRAIRIES. DO BELIEVE THE NON-RUC GUIDANCE IS TOO CONSERVATIVE WITH THIS FRONT/S PROGRESS TONIGHT...SO HAVE EDGED LOW TEMPS DOWN A BIT ESPECIALLY NORTHEAST OF THE HIGHWAY 84 CORRIDOR WHERE THE RUC HAS THIS BOUNDARY ROUGHLY STALLING BY DAYBREAK. THIS BOUNDARY HOWEVER WILL RETREAT BY LATE MORNING AS WINDS ALOFT BACK SWLY AND AMPLIFY MODESTLY AHEAD OF SUNDAY/S UPPER TROUGH. AS WE SAW TODAY...EARLIER MODELS WERE MUCH TOO MOIST WITH 2M DEWPOINTS...BUT THIS WAS EXPECTED IN PRIOR FORECASTS AND WE CONTINUE TO EMPLOY THIS RATIONALE WITH TOMORROW/S SETUP BEHIND THE RETREATING FRONT. NUDGED HIGHS UP A FEW DEGREES ON THE CAPROCK WHERE THE DRIEST AIR WILL BE FOUND AND THIS WILL ALSO RESULT IN SOME FIRE WX CONCERNS...ALTHOUGH NOT TO THE DEGREE THAT WE SAW TODAY. LONG TERM... BROAD SOUTHWESTERLY FLOW WILL BE IN PLACE BY LATE SATURDAY. WHAT IS CURRENTLY A WOUND-UP SPIRAL OFF THE COAST WILL BECOME AN OPEN TROUGH FROM THE GREAT BASIN TO BAJA. NORTH OF THE BORDER...A COMPLEX ELONGATED LOW SPANNING MUCH OF CANADA IS LATITUDINALLY ORIENTED AROUND 55N. MODEL GUIDANCE IS FAIRLY CONSISTENT WITH THE SYNOPTIC SCALE FEATURES OVER THE NEXT 7 DAYS. THE WEST COAST TROUGH IS EXPECTED TO APPROACH ON SUNDAY FOLLOWED BY A MORE SUBTLE EMBEDDED TROUGH INTO MONDAY. ON WEDNESDAY...YET ANOTHER TROUGH AXIS APPROACHES AND STARTS TO DEEPEN BEFORE DIVING INTO THE GULF COAST SATES LATE WEEK. OUR FINAL TROUGH OF THE EXTENDED APPROACHES ON FRIDAY. YET ANOTHER BACK DOOR COLD FRONT SNEAKS INTO THE AREA ON SUNDAY MAKING FCST HIGHS QUITE TRICKY AS THE BOUNDARY HANGS UP FOR SEVERAL HOURS ACROSS THE CWFA. THEN...WITH THE FALL OF NIGHT...THE COLDER AIR SHOULD FILTER INTO THE REGION. OVERNIGHT BUT NOT BEFORE THERE IS SOME OPPORTUNITY FOR PRECIPITATION. MONDAY SHOULD REMAIN DRY AND QUITE COOL BEFORE RETURN FLOW SETS UP ON TUESDAY QUICKLY REBOUNDING TEMPERATURES THOUGH PERHAPS REMAINING A FEW DEGREES SHY OF CLIMATOLOGICAL AVERAGES. ANOTHER COLD FRONT ENTERS THE REGION WEDNESDAY MORNING HELPING TO HOLD TEMPS DOWN ONE MORE DAY BEFORE SOUTHWESTERLY SURFACE FLOW PICKS UP FOR THURSDAY WITH THE POTENTIAL FOR ANOTHER BOUT OF FIRE WEATHER LATE NEXT WEEK. YET ANOTHER PUSH OF COLD AIR ENTERS FOR SEVERE WEATHER AWARENESS DAY. FIRE WEATHER... WIDESPREAD RED FLAG CONDITIONS CONTINUE THIS AFTERNOON ACROSS THE SOUTH PLAINS AND MUCH OF THE ROLLING PLAINS. THE STRONGEST WINDS HAVE SINCE DEPARTED THE REGION...BUT 20-FOOT SPEEDS OF 20-25 MPH WILL CONTINUE UNTIL 6 PM AT WHICH POINT THE RED FLAG WARNING SHOULD BE ALLOWED TO EXPIRE. BY THIS EVENING AND OVERNIGHT...A LIGHT NORTHEAST WIND SHIFT WILL PUSH SOUTHWEST ACROSS THE ROLLING PLAINS AND EASTERN SOUTH PLAINS BEFORE RETREATING NORTHEAST BY LATE SATURDAY MORNING. ELEVATED TO MARGINALLY CRITICAL FIRE WEATHER IS POSSIBLE BY SATURDAY AFTERNOON ON THE CAPROCK AS SOUTHWEST WINDS RISE TO 15 TO 25 MPH WITH MIN RH VALUES FALLING INTO THE LOWER-TO-MID TEENS. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 36 75 32 34 12 / 0 0 20 30 10 TULIA 37 75 25 29 10 / 0 0 20 20 10 PLAINVIEW 39 77 27 32 11 / 0 0 10 20 10 LEVELLAND 39 80 33 45 15 / 0 0 10 20 10 LUBBOCK 38 80 29 40 14 / 0 0 10 20 10 DENVER CITY 44 79 36 54 20 / 0 0 10 20 10 BROWNFIELD 42 80 34 46 18 / 0 0 10 20 10 CHILDRESS 37 68 24 25 10 / 0 0 10 20 10 SPUR 39 80 25 34 13 / 0 0 10 20 10 ASPERMONT 39 83 25 31 12 / 0 0 20 20 10 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 23/33/23
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1009 PM CST FRI FEB 28 2014 .UPDATE... A WEAK FRONT IS IN THE PROCESS OF BACK-DOORING INTO THE AREA FROM THE NORTHEAST...WITH CHILDRESS AND NORTHFIELD ALREADY EXPERIENCING LIGHT EASTERLY BREEZES. THIS FRONT WILL CONTINUE ON ITS SOUTHWESTWARD PUSH THROUGH THE OVERNIGHT HOURS UNTIL STALLING OVER THE CENTRAL SOUTH PLAINS SATURDAY MORNING...THEN RETREATING SATURDAY AFTERNOON. BEHIND THE FRONT...LIGHT EASTERLY WINDS WILL CONTINUE TO TAP INCREASING AMOUNTS OF MOISTURE ALONG THE RED RIVER VALLEY. AS TEMPERATURES CONTINUE TO FALL AND LOW-LEVEL MOISTURE INCREASES...THE PROSPECTS FOR FOG AND LOW CLOUDS WILL INCREASE ACROSS THE EASTERN ZONES...LIKELY AFTER 09Z. THIS LOW CLOUD AND FOG DECK COULD ADVANCE AS FAR WESTWARD AS ROUGHLY A DIMMITT TO PLAINVIEW TO ASPERMONT LINE BY MID-MORNING BEFORE THINNING...LIFTING AND SCATTERING OUT. GIVEN THIS...WE HAVE UPDATED THE FORECAST TO INCLUDE AREAS OF FOG ACROSS ROUGHLY THE NORTHEAST HALF OF THE CWA IN THE 09-16Z TIME-FRAME. EARLY ON...SKY GRIDS WERE DECREASED GIVEN THE MOSTLY CLEAR SKIES CURRENTLY IN PLACE...BUT WERE BOOSTED ACROSS THE NORTHEAST ZONES AFTER 09Z AS THE LOW CLOUDS AND FOG ARE EXPECTED TO FILL IN. ASIDE FROM THE WEATHER AND SKY GRIDS...MINOR ADJUSTMENTS WERE ALSO MADE TO THE TEMPERATURE...DEWPOINT AND RH GRIDS. THE UPGRADED PRODUCTS HAVE BEEN SENT. && .PREV DISCUSSION... /ISSUED 556 PM CST FRI FEB 28 2014/ UPDATE... WINDS CONTINUE TO GRADUALLY DECREASE EARLY THIS EVENING BRINGING AN END TO THE CRITICAL FIRE WEATHER CONDITIONS FOR THE SOUTH PLAINS REGION. THUS...THE RED FLAG WARNING WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 00Z. AVIATION... GUSTY WINDS AT KLBB WILL QUICKLY DIMINISH OVER THE NEXT HOUR OR SO...WITH LIGHT WINDS EXPECTED THROUGH THE REMAINDER OF THE NIGHT. A FRONT WILL MOVE THROUGH KCDS EARLY THIS EVENING WITH LIGHT NORTHEAST TO EASTERLY WINDS IN ITS WAKE. THIS FRONT MAY BRIEFLY EDGE THROUGH KLBB BY 10-12Z WITH AN EASTERLY WIND SHIFT...BUT GUSTY SOUTHWESTERLY WINDS SHOULD RETURN TO THE TERMINAL BY AROUND MIDDAY ON SATURDAY. AT KCDS...EASTERLY WINDS WILL WILL LIKELY PERSIST THROUGH THE PERIOD. IN ADDITION...THERE WILL BE A CHANCE OF LOW CLOUDS DEVELOPING AT KCDS BY AROUND 12Z. IF CLOUDS DO FORM...THEY COULD PERSIST THROUGH MUCH OF THE MORNING BEFORE LIFTING AND SCATTERING OUT. CURRENTLY HAVE INDICATED A MVFR DECK AT KCDS...BUT THERE IS A CHANCE THE CLOUDS COULD BE LOWER...IN THE IFR TO LIFR CATEGORY. AT KLBB...VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF CYCLE. PREV DISCUSSION... /ISSUED 348 PM CST FRI FEB 28 2014/ SHORT TERM... FOLLOWING A COMPACT S/W TROUGH THAT GENERATED TSTORMS IN PARTS OF THE TX PANHANDLE LAST NIGHT...THE AXIS OF STRONG WESTERLY WINDS HAVE SINCE EXITED THE FORECAST AREA ON SCHEDULE. THESE WINDS DID RESULT IN A BIT MORE DRAMA THAN EXPECTED THANKS TO A 59 MPH GUST AS MEASURED BY THE GRAHAM WEST TX MESONET...BUT AS A WHOLE THE BLOWING DUST THIS MORNING WAS NOTHING UNUSUAL FOR THE HARDY RESIDENTS THAT FREQUENT THESE PARTS. ALREADY BY SUNSET...A WEAK COLD FRONT WILL BE EDGING SOUTHWEST ACROSS THE EASTERN PANHANDLE WELL AHEAD OF A BROODING ARCTIC HIGH STILL POISED IN THE WESTERN CANADIAN PRAIRIES. DO BELIEVE THE NON-RUC GUIDANCE IS TOO CONSERVATIVE WITH THIS FRONT/S PROGRESS TONIGHT...SO HAVE EDGED LOW TEMPS DOWN A BIT ESPECIALLY NORTHEAST OF THE HIGHWAY 84 CORRIDOR WHERE THE RUC HAS THIS BOUNDARY ROUGHLY STALLING BY DAYBREAK. THIS BOUNDARY HOWEVER WILL RETREAT BY LATE MORNING AS WINDS ALOFT BACK SWLY AND AMPLIFY MODESTLY AHEAD OF SUNDAY/S UPPER TROUGH. AS WE SAW TODAY...EARLIER MODELS WERE MUCH TOO MOIST WITH 2M DEWPOINTS...BUT THIS WAS EXPECTED IN PRIOR FORECASTS AND WE CONTINUE TO EMPLOY THIS RATIONALE WITH TOMORROW/S SETUP BEHIND THE RETREATING FRONT. NUDGED HIGHS UP A FEW DEGREES ON THE CAPROCK WHERE THE DRIEST AIR WILL BE FOUND AND THIS WILL ALSO RESULT IN SOME FIRE WX CONCERNS...ALTHOUGH NOT TO THE DEGREE THAT WE SAW TODAY. LONG TERM... BROAD SOUTHWESTERLY FLOW WILL BE IN PLACE BY LATE SATURDAY. WHAT IS CURRENTLY A WOUND-UP SPIRAL OFF THE COAST WILL BECOME AN OPEN TROUGH FROM THE GREAT BASIN TO BAJA. NORTH OF THE BORDER...A COMPLEX ELONGATED LOW SPANNING MUCH OF CANADA IS LATITUDINALLY ORIENTED AROUND 55N. MODEL GUIDANCE IS FAIRLY CONSISTENT WITH THE SYNOPTIC SCALE FEATURES OVER THE NEXT 7 DAYS. THE WEST COAST TROUGH IS EXPECTED TO APPROACH ON SUNDAY FOLLOWED BY A MORE SUBTLE EMBEDDED TROUGH INTO MONDAY. ON WEDNESDAY...YET ANOTHER TROUGH AXIS APPROACHES AND STARTS TO DEEPEN BEFORE DIVING INTO THE GULF COAST SATES LATE WEEK. OUR FINAL TROUGH OF THE EXTENDED APPROACHES ON FRIDAY. YET ANOTHER BACK DOOR COLD FRONT SNEAKS INTO THE AREA ON SUNDAY MAKING FCST HIGHS QUITE TRICKY AS THE BOUNDARY HANGS UP FOR SEVERAL HOURS ACROSS THE CWFA. THEN...WITH THE FALL OF NIGHT...THE COLDER AIR SHOULD FILTER INTO THE REGION. OVERNIGHT BUT NOT BEFORE THERE IS SOME OPPORTUNITY FOR PRECIPITATION. MONDAY SHOULD REMAIN DRY AND QUITE COOL BEFORE RETURN FLOW SETS UP ON TUESDAY QUICKLY REBOUNDING TEMPERATURES THOUGH PERHAPS REMAINING A FEW DEGREES SHY OF CLIMATOLOGICAL AVERAGES. ANOTHER COLD FRONT ENTERS THE REGION WEDNESDAY MORNING HELPING TO HOLD TEMPS DOWN ONE MORE DAY BEFORE SOUTHWESTERLY SURFACE FLOW PICKS UP FOR THURSDAY WITH THE POTENTIAL FOR ANOTHER BOUT OF FIRE WEATHER LATE NEXT WEEK. YET ANOTHER PUSH OF COLD AIR ENTERS FOR SEVERE WEATHER AWARENESS DAY. FIRE WEATHER... WIDESPREAD RED FLAG CONDITIONS CONTINUE THIS AFTERNOON ACROSS THE SOUTH PLAINS AND MUCH OF THE ROLLING PLAINS. THE STRONGEST WINDS HAVE SINCE DEPARTED THE REGION...BUT 20-FOOT SPEEDS OF 20-25 MPH WILL CONTINUE UNTIL 6 PM AT WHICH POINT THE RED FLAG WARNING SHOULD BE ALLOWED TO EXPIRE. BY THIS EVENING AND OVERNIGHT...A LIGHT NORTHEAST WIND SHIFT WILL PUSH SOUTHWEST ACROSS THE ROLLING PLAINS AND EASTERN SOUTH PLAINS BEFORE RETREATING NORTHEAST BY LATE SATURDAY MORNING. ELEVATED TO MARGINALLY CRITICAL FIRE WEATHER IS POSSIBLE BY SATURDAY AFTERNOON ON THE CAPROCK AS SOUTHWEST WINDS RISE TO 15 TO 25 MPH WITH MIN RH VALUES FALLING INTO THE LOWER-TO-MID TEENS. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 36 75 32 34 12 / 0 0 20 30 10 TULIA 37 75 25 29 10 / 0 0 20 20 10 PLAINVIEW 39 77 27 32 11 / 0 0 10 20 10 LEVELLAND 39 80 33 45 15 / 0 0 10 20 10 LUBBOCK 38 80 29 40 14 / 0 0 10 20 10 DENVER CITY 44 79 36 54 20 / 0 0 10 20 10 BROWNFIELD 42 80 34 46 18 / 0 0 10 20 10 CHILDRESS 37 68 24 25 10 / 0 0 10 20 10 SPUR 39 80 25 34 13 / 0 0 10 20 10 ASPERMONT 39 83 25 31 12 / 0 0 20 20 10 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 23/33
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
703 PM CST SUN MAR 2 2014 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 230 PM CST SUN MAR 2 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH PRESSURE CENTERED ACROSS THE NORTHERN GREAT PLAINS. TEMPERATURES REMAIN COLD EARLY THIS AFTERNOON WITHIN THE HIGH...WITH READINGS A FEW DEGREES ON EITHER SIDE OF THE ZERO DEGREE MARK. WIND CHILL VALUES REMAIN IN THE TEENS BELOW ZERO AT MANY LOCATIONS OVER EAST- CENTRAL/CENTRAL/NORTH-CENTRAL WISCONSIN. OTHER THAN THE UNSEASONABLY COLD CONDITIONS...SKIES ARE MAINLY CLEAR ACROSS MUCH OF MINNESOTA AND WISCONSIN...THOUGH CIRRUS FROM A SOUTHERN STREAM STORM SYSTEM IS CROSSING THE BORDER INTO SOUTHERN WISCONSIN. OTHER LOW STRATUS IS DRIFTING SOUTH TOWARDS THE NORTHERN SHORELINE OF LAKE SUPERIOR. WITH THE SOUTHERN STORM SYSTEM EXPECTED TO REMAIN WELL SOUTH OF THE REGION...TEMPS AND WIND CHILLS ARE THE MAIN FOCUS AS THE ARCTIC HIGH MOVES EAST TONITE. TONIGHT...ARCTIC HIGH PRESSURE WILL SHIFT SOUTHEAST FROM THE NORTHERN GREAT PLAINS INTO THE NORTHERN MISSISSIPPI VALLEY. BOTH THE NAM AND GFS SHOW THE MOISTURE THAT IS APPROACHING NORTHERN LAKE SUPERIOR DRYING UP AS IT RUNS INTO THE VERY DRY ARCTIC AIRMASS. WILL CONTINUE TO SHOW FEW TO SCT SKY CONDITIONS THIS EVENING ACROSS FAR NORTHERN WISCONSIN IN CASE A LITTLE MOISTURE IS PICKED UP OFF LAKE SUPERIOR. LIKE YESTERDAY...THE NAM IS DEVELOPING A LAKE INDUCED SURFACE TROUGH UP THE SPINE OF LAKE MICHIGAN LATE TONIGHT. AS A RESULT...MAY SEE SCT LAKE CLOUDS MOVE JUST INLAND ALONG THE LAKE MICHIGAN SHORELINE. CONFIDENCE IS NOT HIGH ENOUGH TO ADD FLURRIES INTO THE FORECAST...BUT COULD SEE THAT HAPPENING. THE OTHER ISSUE IS TEMPS/WIND CHILL HEADLINES. THE PRESSURE GRADIENT TIGHTENS BRIEFLY THIS EVENING AND THEN SLACKENS OVERNIGHT WITH THE APPROACHING SURFACE HIGH. CONDITIONS ARE MORE SUPPORTIVE OF DECOUPLING THAN LAST NIGHT AND WILL SHOW THAT TREND OCCURRING MAINLY AFTER 06Z. THIS MAKES FOR A DILEMMA IN REGARDS TO WIND CHILL HEADLINES...WHICH REQUIRE AT 3 KTS OF WIND. THINK THERE COULD BE A FEW HOUR PERIOD OF WIND CHILL CRITERIA BEING MET BEFORE WINDS BECOME CALM WITH VALUES FALLING BETWEEN 20 TO 30 BELOW. TOUGH TO GET EXCITED ABOUT HEADLINES WITH SUCH A SHORT DURATION EVENT...EVEN THOUGH THE CALM WINDS WILL PROMOTE TANKING TEMPERATURES. AFTER COLLAB WITH SURROUNDING OFFICES...DECIDED TO ISSUE WIND CHILLS HEADLINES TO KEEP THE MAP PRETTY. THE MIDNIGHT CREW CAN CANCEL EARLY IF DESIRED. DROPPED LOWS BY PERHAPS A DEGREE IN SPOTS. MONDAY...THE ARCTIC HIGH PRESSURE WILL DRIFT TO THE SOUTHERN GREAT LAKES. LOW LEVEL TEMPS WILL MODERATE AS SURFACE WINDS SHIFT TO THE SOUTHWEST IN THE AFTERNOON. UNDER PLENTY OF SUN...TEMPS SHOULD RISE INTO THE LOWER TEENS. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 230 PM CST SUN MAR 2 2014 NEAR ZONAL FLOW EXPECTED MUCH OF THIS PERIOD WITH TEMPERATURES... WHILE REMAINING BELOW NORM...MODERATE FROM WHAT WE HAVE TODAY. PATTERN AMPLIFIES SOME TOWARD THE WEEKEND WITH RIDGE REBUILDING OVER THE WEST COAST AND TROFFING SETTING UP AGAIN OVER CENTRAL U.S. IN LATER PERIODS FEATURE TO WATCH...SIG SHORT WAVE MOVING THROUGH CENTRAL CANADA. THIS SYSTEM AND FOLLOW ON WEAKER WAVES TO PUSH COLD FRONT THROUGH STATE OVER THE WEEKEND WITH CHANCE FOR PCPN THROUGH PERIOD. GULF MOISTURE NOT A PLAYER...SO AMOUNTS EXPECTED TO BE LIGHT. TEMPERATURES EXPECTED TO DROP BACK INTO LOW TO MID 20S. IN NEAR TERM...TWO PERIODS OF LIGHT SNOW EXPECTED MON NIGHT INTO TUE AND AGAIN TUE EVENING. SHORTWAVES COMBINE WITH WEAK WAA AND JET ENERGY THESE PERIODS...WITH TUE NIGHT SYSTEM AFFECTING MAINLY SOUTH PART OF CWA. FOR MON NIGHT MODELS HAVE BEEN CONSISTENT YESTERDAY AND TODAY WITH CROSS SECTIONS SHOWING WEAK LIFT THROUGH DEEP AREA OF GOOD DENDRICTIC GROWTH RATES. HAVE BUMPED SNOW ACCUMULATIONS UP GIVEN EXPECTED 20 TO 1 SNOW RATIOS. A GOOD INCH TO UP TO TWO INCHES EXPECTED LATE MON NIGHT INTO TUE MORNING. DRY HIGH PRESSURE EXPECTED TO SINK SOUTH INTO NORTHERN WI LATE TUE NIGHT...WED MORN...CLEARING SKIES OUT WED. LIGHT NORTHEAST TO EAST WINDS EXPECTED WILL BRING SMALL CHANCE FOR MAINLY LAKE EFFECT FLURRIES. LATEST VISIBLE SAT IMAGERY TODAY OF LAKE MI SHOWING LIMITED OPEN WATER...SO WILL NOT PUT INTO GRIDS AT THIS TIME. GFS STILL ODD MODEL OUT BEING QUICKER WITH NEXT PLAINS SYSTEM BRINGING PCPN INTO REGION WED NIGHT. HAVE STAYED WITH MAJORITY WITH SLOWER TIMING. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 703 PM CST SUN MAR 2 2014 CLEAR SKIES AND LIGHT WINDS EXPECTED TONIGHT. MIDDLE AND HIGH CLOUDS WILL MOVE IN FROM THE WEST MONDAY BUT IT WILL REMAIN VFR THROUGH THE DAY. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST MONDAY FOR WIZ013-020>022-031-037>040-045-048>050-073-074. WIND CHILL ADVISORY UNTIL 9 AM CST MONDAY FOR WIZ005-010>012-018- 019-030-035-036. && $$ SHORT TERM.....MPC LONG TERM......TE AVIATION.......RDM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
316 PM CST SAT MAR 1 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 315 PM CST SAT MAR 1 2014 FOR EARLY THIS EVENING...A SHORT WAVE TROUGH WILL MOVE QUICKLY EAST THROUGH THE AREA. MUCH OF THE FRONTOGENESIS ASSOCIATED WITH THIS SYSTEM IS LOCATED ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. AS A RESULT...HELD ONTO THE HIGHEST PRECIPITATION PROBABILITIES IN THOSE AREAS THROUGH 02.02Z...AND THEN QUICKLY LOWERED THE CHANCES AS SUBSIDENCE DEVELOPS ACROSS THE REGION. ADDITIONAL SNOW TOTALS WILL BE UP TO AN INCH SOUTH OF A CHARLES CITY IOWA TO LANCASTER WISCONSIN LINE. FOR LATE TONIGHT AND SUNDAY...THE COMBINATION OF TEMPERATURES IN THE 0 TO 20 BELOW RANGE AND NORTH WINDS UP TO 10 MPH WILL PRODUCE WIND CHILLS IN THE 20 TO 35 BELOW RANGE TONIGHT AND SUNDAY MORNING. DUE TO THIS...ISSUED A WIND CHILL ADVISORY. WITH OUR NORTHERN AND WESTERN AREAS...REACHING CRITERIA THIS EVENING...STARTED THEIR WIND CHILL ADVISORY AT 02.00Z. MEANWHILE SOUTHWEST AND CENTRAL WISCONSIN WILL LIKELY NOT REACH CRITERIA UNTIL AFTER MIDNIGHT...SO STARTED THESE AREAS AT 02.06Z. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 315 PM CST SAT MAR 1 2014 FROM SUNDAY NIGHT INTO MONDAY...WIND CHILLS WILL ONCE AGAIN FALL INTO THE -20 TO -35 DEGREE RANGE. AS A RESULT...WE WILL SEE ANOTHER WIND CHILL ADVISORY ISSUED FOR THIS TIME PERIOD ON SUNDAY AFTERNOON. FROM MONDAY NIGHT INTO TUESDAY MORNING...THE 01.12Z MODELS CONTINUE TO SHOW THAT A SHORT WAVE TROUGH WILL MOVE SOUTHEAST THROUGH THE REGION. THE NAM IS THE SLOWEST AT MOVING THIS SYSTEM INTO THE AREA. MEANWHILE THE GFS...GEM...AND ECMWF HAS SNOW MOVING IN THE REGION AS EARLY AS MONDAY EVENING. THE GFS HAS MODERATE TO STRONG 265 TO 280K ISENTROPIC LIFT WHICH QUICKLY SATURATES THESE SURFACES. WITH QPFS RUNNING UP TO 0.05" AND 20 TO 1 SNOW TO LIQUID RATIOS...EXPECT SNOW TOTALS UP TO 1 INCH. EXPECT THE HIGHEST TOTALS TO BE FOUND NORTH OF INTERSTATE 94 WHERE THERE IS THE STRONGEST FRONTOGENESIS AND DEEPEST ISENTROPIC LIFT. FROM THURSDAY INTO FRIDAY...THE DETERMINISTIC MODELS CONTINUE TO SHOW THAT MODERATE WARM AIR ADVECTION WILL DEVELOP AHEAD OF AN APPROACHING SHORT WAVE TROUGH. THE GFS WARMS THE 850 MB TEMPERATURES INTO THE -2 TO 0C RANGE. MEANWHILE THE ECMWF WARM THE 850 MB TEMPERATURES INTO THE 2 TO 5C. EVEN THOUGH THE MODELS ARE CONSISTENTLY WARMING UP THINGS DURING THIS TIME PERIOD...THERE IS STILL A 3 STANDARD DEVIATION SHOWING UP IN THE MAXIMUM AND MINIMUM TEMPERATURES FOR THIS TIME PERIOD IN THE MEN. THE CFS VERSION 2 HAS WARMED UP THIS PERIOD DURING ITS LAST 4 MODEL RUNS. HOWEVER IT STILL HAS ITS MEAN IN THE UPPER 20S. AS A RESULT...STILL A BIT CONCERNED THAT WE MAY BE GOING A BIT TOO HIGH WITH OUR TEMPERATURES DURING THIS TIME PERIOD. HOWEVER MY CONFIDENCE WAS NOT HIGH ENOUGH TO GO AWAY FROM THE MODEL CONSENSUS. FROM FRIDAY NIGHT INTO SATURDAY...THE MODELS CONTINUE TO STRUGGLE ON WHERE THE POLAR JET WILL BE LOCATED. THE ECMWF SUGGESTS THAT IT WILL BE NORTH AND EAST OF THE FORECAST AREA. AS A RESULT...OUR HIGH TEMPERATURES WOULD REMAIN IN THE 30S ON SATURDAY. MEANWHILE THE GFS HAS ITS POLAR JET SOUTH AND WEST OF THE FORECAST AREA AND THE HIGH TEMPERATURES WOULD ONLY BE IN THE TEENS FOR SATURDAY. DUE TO THIS...JUST WENT WITH THE MODEL CONSENSUS WHICH HAS HIGH TEMPERATURES IN THE MID AND UPPER 20S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1127 AM CST SAT MAR 1 2014 THE LIGHT SNOW HAS BEEN MOVING IN FASTER THAN PREVIOUSLY ANTICIPATED...WHICH ALSO MEANS IT SHOULD MOVE OUT FASTER. CONDITIONS HAVE ALREADY GONE DOWN TO IFR AT KRST AND BASED ON RADAR TRENDS AND THE 01.15Z HRRR EXPECT THESE TO CONTINUE INTO THE MIDDLE OF THE AFTERNOON AND THEN START TO IMPROVE WITH VFR CONDITIONS EXPECTED BY LATE AFTERNOON. FOR KLSE...EXPECTING MVFR TO IFR CONDITIONS IN THE LATE AFTERNOON BEFORE IMPROVE BEGINS WITH VFR CONDITIONS BY EARLY AFTERNOON. ONCE THE SHORT WAVE TROUGH MOVES PAST...SUBSIDENCE WILL DEVELOP THIS EVENING ALLOWING THE CLOUDS TO SCATTER OUT OVERNIGHT WITH VFR CONDITIONS EXPECTED FOR THE REMAINDER OF THE PERIOD. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO NOON CST SUNDAY FOR WIZ017-029-032>034. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST SUNDAY FOR WIZ041>044-053>055-061. MN...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO NOON CST SUNDAY FOR MNZ079-086>088-094-095. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST SUNDAY FOR MNZ096. IA...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO NOON CST SUNDAY FOR IAZ008>010-018-019-029. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST SUNDAY FOR IAZ011-030. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...04
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND SUNDAY ISSUED AT 216 PM CST SAT MAR 1 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A STRONG ARCTIC HIGH PRESSURE BUILDING SOUTHEAST TOWARDS THE WESTERN GREAT LAKES THIS AFTERNOON. LOOKING ALOFT...MID-LEVEL CONFLUENCE IS OCCURRING OVER THE NORTHERN PLAINS TO WESTERN GREAT LAKES. ASSOCIATED MID-LEVEL FGEN IN THIS CONFLUENCE ZONE WITH HELP FROM SHORTWAVE ENERGY OVER THE NE/SD IS GENERATING A BAND OF LIGHT SNOW FROM SOUTH DAKOTA TO WESTERN MICHIGAN. ACROSS THE CWA...THIS SNOW IS GENERALLY ALONG AND SOUTH OF ROUTE 29 AND MAY SEE A HALF INCH OF ACCUM FROM WAUTOMA TO MANITOWOC THIS AFTERNOON. NORTHWEST WINDS BEHIND THE SNOW BAND ARE COLD ADVECTING A BITTERLY COLD AIRMASS OUT OF THE 1045MB ARCTIC HIGH. TEMPS THIS AFTERNOON REMAIN BELOW ZERO OVER CENTRAL AND NORTHERN MINNESOTA. CONCERNS INCLUDE TIMING THE END OF THE SNOW...AND WIND CHILLS TONIGHT INTO SUNDAY MORNING. TONIGHT...BROAD MID-LEVEL CONVERGENCE ZONE BETWEEN A NORTHERN STREAM SHEAR AXIS AND SOUTHERN STREAM SHORTWAVE ENERGY WILL SLIDE TO THE SOUTHEAST TO THE SOUTHERN GREAT LAKES AND NORTHERN OHIO VALLEY. THE BAND OF LIGHT SNOW WITHIN THE FGEN OF THIS CONVERGENT ZONE WILL EXIT EAST-CENTRAL WISCONSIN BY THE END OF THE AFTERNOON. NOT SURE IF THE RETURNS OVER EASTERN SOUTH DAKOTA WILL MAKE IT THIS FAR EAST...BUT WILL LEAVE A SMALL CHANCE OVER CENTRAL WISCONSIN EARLY IN THE EVENING. FURTHERMORE...THE MESO-MODELS ARE PICKING UP A MID-LAKE SNOW BAND OVER CENTRAL LAKE MICHIGAN THAT DEVELOPS THIS EVENING AND DROPS SOUTH THROUGH THE NIGHT. ONE OF THE MESO MODELS INDICATES THAT SOME OF THIS MID-LAKE SNOW WILL MOVE INLAND OVER THE LAKE SHORE COUNTIES. GENERALLY DO NOT LIKE THIS IDEA...SINCE SYNOPTIC WINDS WILL BE OFFSHORE AND ANY LAND BREEZE COMPONENT WILL WANT TO SHOVE THE LAKE SNOW TO THE OTHER SIDE OF THE LAKE. WILL KEEP THE CHANCE OF LIGHT SNOW ALONG THE LAKE SHORE THROUGH THE NIGHT...BUT KEEP ACCUMS LIGHT. THE OTHER PROBLEM AREA TONIGHT WILL BE WIND CHILLS ACROSS NORTH-CENTRAL WISCONSIN. ARCTIC HIGH PRESSURE WILL BE BUILDING INTO THE REGION TONIGHT...WITH MID AND HIGH CLOUDS THINNING OUT AFTER MIDNIGHT. EXPECT THE SURFACE GRADIENT TO BE A LITTLE TOO TIGHT FOR DECOUPLING THIS EVENING...BUT LOW LEVEL WINDS SUBSIDE OVERNIGHT SO THINK SURFACE WINDS SHOULD TURN LIGHT AND VARIABLE. TEMPS FALLING BELOW MINUS 20 SEEMS LIKELY...SO STUCK WITH THE PREVIOUS FORECASTERS MIN TEMPS. WITH CLOUDS OVERHEAD IN THE EVENING...FOLLOWED BY THE POTENTIAL FOR DECOUPLING AFTER MIDNIGHT...GENERALLY NOT EXCITED TO ISSUE A WIND CHILL ADVISORY WITH SO MANY QUESTION MARKS...ESPECIALLY AFTER SO MANY LOW WIND CHILL EVENTS ALREADY. BUT WITH OFFICES TO THE WEST ISSUING HEADLINES...WILL FOLLOW SUIT TO BLEND. SUNDAY...ANY LIGHT SNOW NEAR THE SHORELINE OF MANITOWOC AND KEWAUNEE COUNTIES WILL BE EXITING DURING THE MORNING AS DRY ARCTIC AIR FLOWS SOUTHEAST ACROSS THE REGION. SHOULD SEE A MOSTLY SUNNY SKY IN THE AFTERNOON WITH HIGHS IN THE SINGLE DIGITS TO LOW TEENS. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY ISSUED AT 216 PM CST SAT MAR 1 2014 SPLIT FLOW PATTERN EARLY IN THIS PERIOD WILL CONSOLIDATE MONDAY WITH SOME MODERATION OF COLD EXPECTED AS MORE ZONAL PATTERN SETS UP. THEREAFTER...SERIES OF WEAK SYSTEMS MOVING THROUGH FLOW TO BRING PCPN TO AREA FROM TIME TO TIME. ISSUES WILL BE TIMING THESE SYSTEMS. MOISTURE WILL ALSO BE LIMITED SO AMOUNTS WILL ON LIGHT SIDE. BY THU...850MB TEMPS RISE INTO SINGLE DIGITS BELOW ZERO...WITH SURFACE TEMPS APPROACHING 30? PATTERN BEGINS TO AMPLIFY ONCE AGAIN AS MOVE INTO THE WEEKEND WITH TROF OVER CENTER OF U.S. COLDER TEMPERATURES RETURN...THOUGH MEDIUM RANGE MODELS SUGGEST THIS COLDER TURN TO BE SHORT LIVED. IN NEAR TERM....HIGH PRESSURE BUILDING IN OUT OF NORTHERN PLAINS AND LIGHT WINDS TO LEAD TO CONTINUING VERY COLD PERIOD THROUGH MONDAY. RECORD HIGH TEMP FOR MARCH 3RD MAY BE IN JEOPARDY. QUESTION ON NEED FOR WIND CHILL ADVISORY SUN NIGHT AS WINDS EXPECTED TO DROP OFF NORTH CENTRAL AND CENTRAL ESPECIALLY AFTER 6Z. WINDS ALOFT ONLY AROUND 10KTS THROUGH 850MB. WAA PATTERN...LFQ OF JET MOVING THROUGH PLAINS TO LEAD TO NEXT CHANCE OF PCPN LATE MON NIGHT INTO TUE. STAYED WITH CHANCE POPS GIVEN MOISTURE CONCERNS WITH EXITING DRY SURFACE HIGH PRESSURE. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1113 AM CST SAT MAR 1 2014 ANOTHER ROUND OF LIGHT SNOW WILL SPREAD ACROSS SOUTHERN WISCONSIN THIS AFTERNOON. THE NORTHERN EDGE WILL CLIP CENTRAL WISCONSIN BUT SHOULD REACH INTO EAST-CENTRAL WISCONSIN BY MID TO LATE AFTERNOON. THE FOX VALLEY AND LAKE SHORE TAF SITES SHOULD SEE VSBYS/CIGS FALL TO MVFR CONDITIONS...AND POSSIBLY IFR AT MTW FOR A PERIOD. NOT EXPECTING MORE THAN AN INCH OF ACCUMULATION THOUGH. THE MAIN AREA OF SNOW WILL EXIT BY LATE IN THE EVENING...THEN MODELS ARE DEPICTING A BAND OF SNOW DEVELOPING OVER LAKE MICHIGAN LATE TONIGHT. SOME INDICATIONS THAT THIS BAND WILL BRUSH BY MTW INTO SUNDAY MORNING. WILL KEEP MVFR CONDITIONS AT MTW THROUGH THEN. OTHERWISE...CONDITIONS TO TURN VFR ELSEWHERE OVERNIGHT. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO NOON CST SUNDAY FOR WIZ005-010>013-018-019-021-030-035-036. && $$ SHORT TERM.....MPC LONG TERM......TE AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1127 AM CST SAT MAR 1 2014 .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 230 AM CST SAT MAR 1 2014 BROAD UPPER LEVEL TROUGH IS PROGGED TO HOLD ACROSS SOUTHERN CANADA...KEEPING THE BULK OF ITS ENERGY TO THE NORTH. HOWEVER...IT DOES HELP ENHANCE TEMP GRADIENT/FRONTOGENETIC FORCING FARTHER SOUTH...WHICH WILL PLAY A KEY ROLE IN SNOW CHANCES TODAY. NORTH- SOUTH RUNNING X-SECTION POINTS TO A GOOD AMOUNT OF SLOPING FRONTOGENETIC FORCING...MOSTLY IN THE 500-850 MB LAYER...STRONGEST SOUTH OF I-90...AND FOCUSED FROM 21-06Z TONIGHT. SLOPING WARM AIR ADVECTION ALSO...SOUTH TO NORTH. MEANWHILE...SOME HINTS THAT THERE COULD BE SOME UPPER LEVEL SUPPORT VIA THE RIGHT ENTRANCE REGION OF A 150 KT JET STREAK WORKING ACROSS THE GREAT LAKES. AMPLE FORCING FOR PCPN PRODUCTION...BUT ACROSS THE SOUTH. MOISTURE DOESN/T APPEAR TO BE AN ISSUE...WITH RH FIELDS AND SOUNDINGS POINTING TO AMPLE SATURATION. SO...SNOW WILL FALL ACROSS IOWA/SOUTHERN WI...WITH MOST ACCUMULATIONS STAYING SOUTH OF I-90. AMOUNTS FROM 1-3" LOOK REASONABLE AT THIS TIME. ANOTHER NIGHT OF BITTER COLD WITH TEMPERATURES EXPECTED TO TUMBLE INTO THE TEENS TO SINGLE DIGITS BELOW NORMAL. SOUTHERN LOCATIONS WILL STAY A BIT WARMER THANKS TO CLOUDS LINGERING IN THESE AREAS LONGER. WINDS WON/T BE STRONG...BUT ENOUGH THAT WIND CHILLS FROM 20 TO 35 BELOW ARE EXPECTED...AND A WIND CHILL ADVISORY WILL BE NEEDED. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 230 AM CST SAT MAR 1 2014 BITTER COLD IS GOING TO STICK AROUND FOR A FEW MORE DAYS AS ECMWF 850 MB TEMPS HOVER CLOSE TO -2 THROUGH MONDAY. HIGH PRESSURE WORKS OVERHEAD SUN-MON...RESULTING IN MOSTLY CLEAR SKIES AND GOOD RADIATIONAL COOLING AT NIGHT. FRESH SNOWFALL FROM FRIDAY AND TODAY WILL AID THE COOLING POTENTIAL. LOWS ARE EXPECTED TO DROP WELL INTO THE MID TO UPPER TEENS BELOW NORMAL FOR MONDAY. ALTHOUGH WINDS WILL BE LIGHT TO CALM AT TIMES...ANOTHER WIND CHILL ADVISORY WILL BE NEEDED. EVEN A 4 MPH WIND WILL MAKE IT 7 TO 8 DEGREES COLDER. THE GFS/ECMWF STILL HOLDING ON COURSE WITH A SHIFT TO A MORE ZONAL FLOW A LOFT THIS WEEKEND...CONTINUING THROUGH MUCH OF NEXT WEEK. THE BITTER COLD WILL SHUNT BACK TO THE NORTH...ALLOWING FOR MODERATING TEMPERATURES. TRENDS ALSO FAVOR HITTING/EXCEEDING THE FREEZING MARK FOR PARTS OF THE FORECAST AREA BY THU/FRI. EC A BIT MORE AGGRESSIVE WITH ITS WARMING...BUT THE FLOW ALLOWS FOR SOME BIGGER SWING. WILL STAY WITH THE WARMING - HOPING FOR TEMPS MORE NORMAL FOR EARLY MARCH. ANYTHING MORE WOULD BE A BONUS. THE ZONAL FLOW WILL ALSO ACT AS A HIGHWAY FOR VARIOUS UPPER LEVEL PERTURBATIONS TO SPIN ACROSS...OR CLOSE TO...THE UPPER MISSISSIPPI RIVER VALLEY. THERE WILL BE DIFFERENCES IN THE MODELS WITH THESE SMALL SYSTEMS...POSITIONING AND TIMING...SO TRYING TO NAIL DOWN WHERE/WHEN THE BEST SNOW CHANCES WILL BE IS PROBLEMATIC. WILL STICK WITH THE CONSENSUS SOLUTION FOR NOW...WHICH BRINGS A LOT OF SMALL CHANCES DAY TO DAY. THERE SHOULD BE MORE CLARITY TO THE VARIOUS PRECIPITATION THREATS AS WE GET WITHIN 72 HOURS. SUFFICE TO SAY...TRENDS ARE FAVORING SOME WARMING TOWARD THE END OF NEXT WEEK...WITH A MORE ACTIVE UPPER LEVEL FLOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1127 AM CST SAT MAR 1 2014 THE LIGHT SNOW HAS BEEN MOVING IN FASTER THAN PREVIOUSLY ANTICIPATED...WHICH ALSO MEANS IT SHOULD MOVE OUT FASTER. CONDITIONS HAVE ALREADY GONE DOWN TO IFR AT KRST AND BASED ON RADAR TRENDS AND THE 01.15Z HRRR EXPECT THESE TO CONTINUE INTO THE MIDDLE OF THE AFTERNOON AND THEN START TO IMPROVE WITH VFR CONDITIONS EXPECTED BY LATE AFTERNOON. FOR KLSE...EXPECTING MVFR TO IFR CONDITIONS IN THE LATE AFTERNOON BEFORE IMPROVE BEGINS WITH VFR CONDITIONS BY EARLY AFTERNOON. ONCE THE SHORT WAVE TROUGH MOVES PAST...SUBSIDENCE WILL DEVELOP THIS EVENING ALLOWING THE CLOUDS TO SCATTER OUT OVERNIGHT WITH VFR CONDITIONS EXPECTED FOR THE REMAINDER OF THE PERIOD. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RIECK LONG TERM....RIECK AVIATION...04
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
345 AM EST MON MAR 3 2014 .SYNOPSIS... AN AREA OF LOW PRESSURE AND BACK DOOR COLD FRONT WILL MOVE THROUGH THIS AFTERNOON AND EVENING PROVIDING A CHANCE OF SHOWERS FOLLOWED BY MUCH COOLER TEMPERATURES. COOL HIGH PRESSURE WILL REMAIN ACROSS THE REGION TUESDAY THROUGH WEDNESDAY...WITH A SLIGHT CHANCE OF SHOWERS MAINLY ACROSS SOUTHERN AREAS POSSIBLE TUESDAY NIGHT AND WEDNESDAY. AN AREA OF LOW PRESSURE RIDING BY TO OUR SOUTH AND EAST WILL PROVIDE A BETTER CHANCE OF RAIN LATE WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...POSSIBLY LINGERING INTO FRIDAY. FAIR WEATHER EXPECTED SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... COLD FRONT TO OUR NORTH AND WEST WITH SURFACE HIGH PRESSURE RIDGE WELL TO OUR SE. SW LOW LEVEL FLOW AND UPPER LEVEL CLOUDINESS KEEPING OUR TEMPS WARM EARLY THIS MORNING. STRONG UPPER LEVEL DISTURBANCE...APPROACHING THE LOWER MISSISSIPPI VALLEY EARLY THIS MORNING...WILL MOVE EAST ACROSS THE CAROLINAS THIS AFTERNOON AND EVENING. SURFACE LOW PRESSURE WILL DEVELOP ALONG THE FRONT AND MOVE EAST ALONG IT. COLD FRONT WILL BACK DOOR THROUGH OUR FORECAST AREA (FA) FROM THE NORTH BEHIND THE DEPARTING SURFACE LOW THIS AFTERNOON AND EVENING. MAIN QUESTION INVOLVES PRECIP TYPE. EXPECT A RAPID COOL DOWN WITH SHALLOW COLD AIR MOVING IN BEHIND THE FRONT ACCOMPANIED BY A WIND SHIFT WITH BREEZY NE WINDS. HOWEVER AT THE SAME TIME THE LOW LEVEL COLD AIR WILL BE MOVING IN...MODELS INDICATE MID AND UPPER LEVELS WILL BE DRYING OUT. SO...AT THIS TIME..IT APPEARS A BRIEF PERIOD OF LIGHT SLEET OR FREEZING DRIZZLE WILL BE POSSIBLE MAINLY FOR THE NE FA THIS EVENING AND EARLY TONIGHT. NO SIGNIFICANT ACCUMULATION EXPECTED. IMPACT EXPECTED TO BE MINIMAL...SO WILL NOT ISSUE AN ADVISORY. WIND GUSTS AROUND 25 KTS AT TIMES TODAY AND TONIGHT BOTH AHEAD OF AND BEHIND THE FRONT. WIND GUSTS ON WARMER AREA LAKES TONIGHT COULD APPROACH LAKE WIND ADVISORY CRITERIA...BUT CONFIDENCE A LITTLE TOO LOW TO ISSUE LWA AT THIS TIME. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... FRONT TO PUSH TO OUR SOUTH AND EAST WITH HIGH PRESSURE BUILDING INTO THE EASTERN SEABOARD. MODELS INDICATE A SERIES OF UPPER IMPULSES TO MOVE ACROSS THE REGION TUE/WED LEADING TO A SURFACE WAVE OR TWO RIDING ALONG THE STALLED FRONT AND POSSIBLY BRINGING SOME LIGHT PRECIPITATION INTO OUR REGION. GFS APPEARS TO BE AN OUTLIER WITH A STRONGER SURFACE LOW AND HIGHER POPS. WILL FAVOR SHORT RANGE ENSEMBLE GUIDANCE DUE TO MODEL DISCREPANCY...AND GIVEN APPEARANCE OF DRY MID LEVELS...THINK SLIGHT CHANCE POPS FAVORING THE SOUTHERN FA TUE NT AND WED LOOKS OK. LOOKING AT PARTIAL THICKNESS VALUES AND FORECAST SOUNDINGS...PRECIP TYPE EXPECTED TO BE ALL RAIN. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... STRONGER UPPER ENERGY MOVING INTO THE SE CONUS WILL PROMOTE A MORE SIGNIFICANT SURFACE LOW DEVELOPING ALONG THE OLD STALLED FRONT TO OUR SOUTH PROVIDING MOISTURE RETURN INTO OUR FA FOR WED NT THRU THU NT. STILL SOME DIFFERENCES NOTED BETWEEN GFS AND ECMWF WITH ECMWF STRONGER WITH THE UPPER LOW AND FARTHER NORTH WITH THE SURFACE LOW...THUS PROVIDING A WETTER SOLUTION FOR OUR FA. LARGE RANGE IN POPS NOTED IN GFS ENSEMBLE GUIDANCE. HPC GUIDANCE PROVIDING LIKELY POPS...IN LINE WITH ONGOING FORECAST. IN SITU WEDGE AT THE SURFACE. LATEST MODEL GUIDANCE TRENDING A LITTLE WARMER WITH LOW LEVEL TEMPS/THICKNESS VALUES AND SURFACE WET BULB TEMPS...AND IT STILL APPEARS ALL RAIN FOR THE PRECIP TYPE. ECMWF ALSO SLOWER WITH THE UPPER SYSTEM MOVING OUT WITH INDICATIONS OF LIGHT PRECIP POSSIBLY LINGERING THROUGH FRIDAY. HIGH PRESSURE TO BUILD IN FOR SATURDAY. GFS BRINGS THE NEXT FRONT IN SUNDAY...WHILE ECMWF APPEARS TO HOLD OFF UNTIL MAYBE SUN NT OR MON. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... A SOUTHWEST FLOW WILL OCCUR BETWEEN HIGH PRESSURE OFF THE SOUTHEAST COAST AND THE APPROACHING STRONG COLD FRONT. EXPECT FRONTAL PASSAGE DURING THE 19Z TO 22Z TIME FRAME. MOISTURE WILL BE ON THE INCREASE AHEAD OF THE FRONT. THE NAM AND GFS MOS PLUS SREF GUIDANCE MAINTAIN VFR CONDITIONS THROUGH THE MORNING. HOWEVER...THE 23Z HRRR SHOWED AN IFR CEILING SPREADING INTO THE AREA FROM THE SOUTHWEST IN AN ISENTROPIC LIFT PATTERN. HOWEVER...NEITHER THE NAM/GFS SHOWED ENOUGH LIFT TO PRODUCE CLOUDS LATER THIS MORNING. LEANED TOWARD THE MAV AND MET MOS AND MAINTAINED VFR CONDITIONS BUT CONFIDENCE IS NOT HIGH BECAUSE OF THE INCONSISTENT HRRR GUIDANCE. MIXING SHOULD HELP PREVENT FOG DURING THE EARLY MORNING HOURS. THE LATEST KCAE 88D VAD WIND PROFILE INDICATED SIGNIFICANT LOW-LEVEL WIND SHEAR. VWP CURRENTLY SHOWS A STRONG SOUTH SOUTHWEST 40 TO 45 KT JET FROM 1K FT AND ABOVE. THE NAM INDICATED SIGNIFICANT WIND SHEAR SHOULD CONTINUE UNTIL AROUND 14Z WHEN HEATING AND MIXING SHOULD BECOME MORE DOMINATE. LATER IN THE DAY...THE NAM AND GFS MOS DIFFERED WITH THE NAM SHOWING IFR CEILINGS DEVELOPING JUST BEHIND THE FRONT. THE GFS MOS INDICATED LOW-END VFR OR MVFR CEILINGS. WE AVERAGED THIS GUIDANCE AND FORECASTED MVFR CEILINGS. THE NAM MOS MAY BE TOO LOW WITH ITS CEILING FORECAST BECAUSE CONSIDERABLE WIND SHOULD HELP HOLD UP CEILINGS. THERE MAY ALSO BE RESTRICTIONS ASSOCIATED WITH RAIN NEAR AND BEHIND THE FRONT BUT BELIEVE THIS RAIN WILL BE MAINLY LIGHT WITH LIMITED EFFECT ON VISIBILITY. WINDS WILL BE ESPECIALLY GUSTY AHEAD OF THE FRONT DURING THE DAY MONDAY. THE GFS LAMP INDICATED GUSTS OF 15 TO 20 KNOTS. THE NAM MOMENTUM TRANSFER TOOL SUPPORTED GUSTS NEAR 25 KNOTS. THE NAM AND GFS MOS...EVEN WITH LOSS OF DAYTIME HEATING...STRONG CAA AND TIGHT PRESSURE GRADIENT WILL PRODUCE BREEZY CONDITIONS THIS EVENING BEHIND THE ARCTIC FRONT WITH NORTH NORTHEAST WINDS AROUND 15 KTS WITH GUSTS AROUND 20 KTS. EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS MAY LINGER DURING THE REST OF MONDAY NIGHT. LOW PRESSURE TRACKING NORTHEASTWARD ALONG THE SOUTHEAST COAST MAY RESULT IN WIDESPREAD MVFR OR IFR CONDITIONS WEDNESDAY NIGHT THROUGH FRIDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1244 AM EST MON MAR 3 2014 .SYNOPSIS... WELL BELOW NORMAL TEMPERATURES TONIGHT WITH SOUTHERLY FLOW AHEAD OF AN ARCTIC FRONT. THE COLD FRONT WILL CROSS THE REGION MONDAY AFTERNOON BRINGING LIGHT RAIN SHOWERS TO THE AREA. DRY BUT COLDER WEATHER EXPECTED FROM TUESDAY THROUGH WEDNESDAY AS ARCTIC AIR SETTLES INTO THE REGION. ANOTHER STRONGER SYSTEM WILL IMPACT THE REGION WEDNESDAY NIGHT THROUGH FRIDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... AN ARCTIC COLD FRONT CONTINUES TO EXPAND EASTWARD ACROSS THE NATION WHERE TEMPERATURES AT THE CENTER OF THE SURFACE HIGH ARE WELL BELOW ZERO OVER THE DAKOTAS AND NEBRASKA AND IOWA. EARLIER THIS EVENING AT 23Z TEXAS HAD A TEMPERATURE RANGE FROM 92 DEGREES IN THE SOUTHERN PART OF THE STATE TO 8 DEGREES IN THE PANHANDLE! THIS ARCTIC FRONT WILL BE SLOW TO CROSS THE MOUNTAINS OVERNIGHT BUT WILL EVENTUALLY MAKE IT OVER AND SPILL DOWN TOWARDS THE FORECAST AREA BY TOMORROW MORNING. SOUTHERLY FLOW AHEAD OF THE FRONT TONIGHT WILL HELP KEEP THE BOUNDARY LAYER MIXED AND LEAD TO WELL ABOVE NORMAL TEMPERATURES WITH LOWS IN THE LOWER 50S. CLOUDS WILL BE INCREASING LATE TONIGHT AS THE FRONT AND UPPER SYSTEM APPROACH. && .SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... MONDAY AND MONDAY NIGHT...LOW PRESSURE AND ASSOCIATED COLD FRONT WILL BEGIN THE DAY JUST WEST OF THE FORECAST AREA. THE COLD FRONT WILL RAPIDLY MOVE EASTWARD INTO THE WESTERN MIDLANDS BY EARLY AFTERNOON THEN THROUGH THE EASTERN MIDLANDS DURING THE MID AFTERNOON HOURS. TEMPERATURES WILL BE THE MAIN ISSUE THROUGH THE DAY AS STRONG COLD AIR ADVECTION WILL ACCOMPANY THE FRONT. TEMPERATURES WILL REACH DAYTIME HIGHS AROUND MIDDAY IN THE NORTHERN AND WESTERN MIDLANDS AND EARLY AFTERNOON IN THE EASTERN MIDLANDS. TEMPERATURES BEHIND THE FRONT WILL BEGIN TO QUICKLY FALL WITH LOWER 40S ENTERING THE NORTHERN MIDLANDS BY EARLY EVENING. MOISTURE WITH THE FRONT WILL BE MOVING EASTWARD AS THE COLD AIR ENTERS THE FORECAST AREA...HOWEVER POTENTIAL FOR SOME SLEET REMAINS ACROSS PRIMARILY LANCASTER AND CHESTERFIELD COUNTIES. AS SUCH HAVE REMAINED WITH CHANCE RAIN SHOWERS AND A SLIGHT CHANCE OF SLEET MIXED IN FOR LANCASTER AND CHESTERFIELD. WITH THE SHORT TIME FROM OF AVAILABLE MOISTURE AND WARM GROUND TEMPERATURES DO NOT EXPECT ANY ACCUMULATION. TEMPERATURES MONDAY NIGHT WILL CONTINUE FALLING AS STRONG COLD AIR ADVECTION OVERTAKES THE REGION WITH LOWS IN THE LOWER 20S ALONG THE NC LINE AND LOWER 30S IN THE CSRA. TUESDAY AND TUESDAY NIGHT...COLD FRONT WILL MOVE WELL OFFSHORE BY TUESDAY MORNING WITH A WEAK RIDGE OVER THE AREA. CLOUDS WILL INCREASE THROUGH THE DAY AS AN UPPER LEVEL DISTURBANCE IN THE WESTERN GULF OF MEXICO PUSHES MOISTURE NORTHWARD. COLD AIR ADVECTION REMAINING BEHIND THE COLD FRONT WILL KEEP TEMPERATURES WELL BELOW NORMAL THROUGH THE DAY WITH DAYTIME HIGHS RANGING FROM THE MID 40S IN THE NORTHERN MIDLANDS TO AROUND 50 IN THE CSRA. LOWS TUESDAY NIGHT WILL BE IN THE UPPER 20S TO LOWER 30S. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... UPPER LEVEL PATTERN WILL REMAIN MODERATELY AMPLIFIED THROUGH THE LONG TERM WITH AMPLIFICATION OVER THE SOUTHEAST FROM WEDNESDAY NIGHT ONWARD. MODELS ARE IN GOOD AGREEMENT SYNOPTICALLY WITH DIFFERENCES IN TIMING AND INTENSITY THROUGH THE LONG TERM...ESPECIALLY REGARDING THE LOW CROSSING THE REGION WEDNESDAY NIGHT THROUGH FRIDAY. UPPER LEVEL TROUGH WILL BEGIN DEEPENING OVER THE SOUTHERN PLAINS WEDNESDAY AFTERNOON WITH A WEAK LOW DEVELOPING IN THE WESTERN GULF STATES WEDNESDAY NIGHT. THE LOW WILL CONTINUE TRACKING EASTWARD REACHING THE FL PANHANDLE BY THURSDAY AFTERNOON. MODEL SOLUTIONS DIVERGE FOR THURSDAY NIGHT ONWARD AS CURRENTLY THE GFS TRACKS THE LOW RAPIDLY NORTHWARD ALONG THE COAST AND OFFSHORE OF NEW ENGLAND BY FRIDAY MORNING...WHILE THE ECMWF MOVES THE LOW MUCH SLOWER KEEPING IT OFFSHORE OF THE CAROLINAS FRIDAY MORNING. HAVE REMAINED CONSERVATIVE AND MADE FEW CHANGES TO THE FORECAST FOR THURSDAY NIGHT ONWARD DUE TO SIGNIFICANT RUN TO RUN MODEL CHANGES OVER THE PAST COUPLE OF RUNS KEEPING CONFIDENCE LOW. MODELS AGREE WEAK HIGH PRESSURE WILL BUILD IN TO THE REGION FRIDAY NIGHT THROUGH SATURDAY WITH THE NEXT SYSTEM APPROACHING ON SUNDAY. TEMPERATURES THROUGH THE LONG TERM WILL BE BELOW NORMAL. && .AVIATION /06Z MONDAY THROUGH SATURDAY/... A SOUTHWEST FLOW WILL OCCUR BETWEEN HIGH PRESSURE OFF THE SOUTHEAST COAST AND THE APPROACHING STRONG COLD FRONT. EXPECT FRONTAL PASSAGE DURING THE 19Z TO 22Z TIME FRAME. MOISTURE WILL BE ON THE INCREASE AHEAD OF THE FRONT. THE NAM AND GFS MOS PLUS SREF GUIDANCE MAINTAIN VFR CONDITIONS THROUGH THE MORNING. HOWEVER...THE 23Z HRRR SHOWED AN IFR CEILING SPREADING INTO THE AREA FROM THE SOUTHWEST IN AN ISENTROPIC LIFT PATTERN. HOWEVER...NEITHER THE NAM/GFS SHOWED ENOUGH LIFT TO PRODUCE CLOUDS LATER THIS MORNING. LEANED TOWARD THE MAV AND MET MOS AND MAINTAINED VFR CONDITIONS BUT CONFIDENCE IS NOT HIGH BECAUSE OF THE INCONSISTENT HRRR GUIDANCE. MIXING SHOULD HELP PREVENT FOG DURING THE EARLY MORNING HOURS. THE LATEST KCAE 88D VAD WIND PROFILE INDICATED SIGNIFICANT LOW-LEVEL WIND SHEAR. VWP CURRENTLY SHOWS A STRONG SOUTH SOUTHWEST 40 TO 45 KT JET FROM 1K FT AND ABOVE. THE NAM INDICATED SIGNIFICANT WIND SHEAR SHOULD CONTINUE UNTIL AROUND 14Z WHEN HEATING AND MIXING SHOULD BECOME MORE DOMINATE. LATER IN THE DAY...THE NAM AND GFS MOS DIFFERED WITH THE NAM SHOWING IFR CEILINGS DEVELOPING JUST BEHIND THE FRONT. THE GFS MOS INDICATED LOW-END VFR OR MVFR CEILINGS. WE AVERAGED THIS GUIDANCE AND FORECASTED MVFR CEILINGS. THE NAM MOS MAY BE TOO LOW WITH ITS CEILING FORECAST BECAUSE CONSIDERABLE WIND SHOULD HELP HOLD UP CEILINGS. THERE MAY ALSO BE RESTRICTIONS ASSOCIATED WITH RAIN NEAR AND BEHIND THE FRONT BUT BELIEVE THIS RAIN WILL BE MAINLY LIGHT WITH LIMITED EFFECT ON VISIBILITY. WINDS WILL BE ESPECIALLY GUSTY AHEAD OF THE FRONT DURING THE DAY MONDAY. THE GFS LAMP INDICATED GUSTS OF 15 TO 20 KNOTS. THE NAM MOMENTUM TRANSFER TOOL SUPPORTED GUSTS NEAR 25 KNOTS. THE NAM AND GFS MOS...EVEN WITH LOSS OF DAYTIME HEATING...STRONG CAA AND TIGHT PRESSURE GRADIENT WILL PRODUCE BREEZY CONDITIONS THIS EVENING BEHIND THE ARCTIC FRONT WITH NORTH NORTHEAST WINDS AROUND 15 KTS WITH GUSTS AROUND 20 KTS. EXTENDED AVIATION OUTLOOK...MVFR OR IFR CONDITIONS MAY LINGER DURING THE REST OF MONDAY NIGHT. LOW PRESSURE TRACKING NORTHEASTWARD ALONG THE SOUTHEAST COAST MAY RESULT IN WIDESPREAD MVFR OR IFR CONDITIONS WEDNESDAY NIGHT THROUGH FRIDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1200 AM CST MON MAR 3 2014 .DISCUSSION... 258 PM CST THE PRIMARY FOCUS IN THE FORECAST WAS ON THE DEGREE OF THE COLD THE NEXT 24 HOURS...AT RECORD LEVELS IN SOME PLACES...AND THEN SNOW CHANCES THIS FIRST WEEK OF METEOROLOGICAL "SPRING". TONIGHT... THE LOCAL AREA FINDS ITSELF SQUEEZED BETWEEN A VERY DEEP UPPER LOW ACROSS HUDSON BAY AND A WELL-DEFINED CLOSED LOW ACROSS THE SOUTHERN PLAINS. THIS SOUTHERN SYSTEM IS PROGRESSING DUE EAST AND CREATING WIDESPREAD SNOW AND ICE TO OUR SOUTH. THIS FEATURE ALSO WILL CONTINUE HIGH CLOUDS ACROSS THE FORECAST AREA THIS EVE WITH SOUTHWEST FLOW ABOVE 15K FT. BUT ASIDE FROM THAT...THE CONFLUENCE ALOFT OVER THE SURFACE HIGH PRESSURE RIDGE WILL KEEP CONDITIONS TRANQUIL. THE LAKE EFFECT SNOW SHOWERS FROM EARLIER TODAY HAVE DIMINISHED IN INTENSITY WITH LESS CONVERGENCE AND JUST DEEPER DRY AIR ADVECTION. WHILE SOME LIGHT SHOWERS ARE ANTICIPATED AT TIMES TONIGHT AND EVEN MONDAY MORNING INTO FAR NORTHWEST INDIANA...ANY ADDITIONAL ACCUMULATION LOOKS TO BE PRETTY LIGHT. WITH THE CENTER OF THE 1039MB HIGH REMAINING EAST OF THE AREA TONIGHT...NORTHWEST WINDS WILL CONTINUE AT ENOUGH OF A SPEED FOR RARE MARCH WIND CHILL CONCERNS...BUT NOT SURPRISING GIVEN THE FORTITUDE OF THIS COOL SEASON. THE AFOREMENTIONED CLOUDS AND WINDS SHOULD HELP TO OFFSET RAPID EVE COOLING...BUT A SLOW STEADY DROP IS ANTICIPATED. OUTSIDE OF CHICAGO...LOWS ARE FORECAST TO DROP TO BELOW ZERO IN MOST AREAS. SEE THE CLIMATE DISCUSSION BELOW FOR MORE. THE WIND CHILLS FALL OUT AT -15 TO -25 ACROSS NORTH CENTRAL ILLINOIS AND THE NORTH AND FAR WEST SIDES OF THE CHICAGO METRO WHICH IS WORTHY OF AN ADVISORY. MONDAY... THE HIGH WILL MOVE DIRECTLY OVER THE REGION WITH SOME SUNSHINE. IT IS ALWAYS A BATTLE THIS TIME OF YEAR WITH COLD AIR OVER SNOW COVER VERSUS THE INCREASING SUN ANGLE. GIVEN THE 925MB TEMPS OF -16C FORECAST AND OVER SNOW COVER...CLIMATOLOGICALLY THIS WOULD FAVOR FORECAST HIGH IN THE TEENS AND HAVE GONE THAT ROUTE. AGAIN SEE THE CLIMATE DISCUSSION BELOW FOR THE RECORD LOW MAXS. CLOUDS LOOK TO BE ON THE INCREASE RAPIDLY MONDAY NIGHT AND THAT SHOULD KEEP MINS UP FROM WHAT WOULD OTHERWISE BE ANOTHER NIGHT BELOW ZERO IN MANY PLACES. IF CLOUDS DO COME IN SLOWER DURING THE EVE THAT COULD LEAD TO A MORE RAPID DROP...BUT RIGHT NOW CONFIDENCE IN CLOUD COVER IS FAIRLY HIGH. TUESDAY AND BEYOND... THE UNSETTLED WEST NORTHWEST FLOW STILL LOOKS TO PREVAIL DURING MIDWEEK. WITH THE QUICK PROGRESSIVE NATURE OF THESE SYSTEMS...NAMELY EARLY TUESDAY AND THEN AGAIN TUESDAY NIGHT AND EARLY WEDNESDAY...IT IS NOT SURPRISING TO SEE CONTINUED MODEL SPREAD. BELIEVE THAT THE FIRST DISTURBANCE EARLY TUESDAY WILL REMAIN PRIMARILY TO THE NORTH GIVEN THE DRY RIDGING OVER THE AREA. THE ELEVATED BAROCLINIC ZONE SHIFTS SOMEWHAT SOUTH IN ITS WAKE...WHICH WOULD ALLOW THE THE TUESDAY NIGHT/EARLY WED SYSTEM A LITTLE BETTER CHANCE TO IMPACT THE AREA. AGAIN THERE IS LITTLE LOW-LEVEL INFLUENCE WITH THIS SYSTEM AND DEEP MOISTURE VALUES LOOK LOW...SO ANY SNOW AMOUNTS WOULD APPEAR MINOR IF IT WERE TO MATERIALIZE...BUT SOMETHING THAT COULD HAVE IMPACTS DEPENDING ON THE TIMING. MODEL SPREAD REALLY GETS LARGE BEYOND THAT AND SO HAVE NOT MADE ANY MAJOR CHANGES TO POPS. HAVE INCREASED THEM SOMEWHAT LATE IN THE WEEK INTO SATURDAY. BESIDES THE FACT IT ALWAYS SNOWS ON SATURDAY /PARTIALLY JOKING/...THE EC AND GEM BOTH HAVE A TIGHT BAROCLINIC ZONE AND AN UPPER DISTURBANCE SIMILAR TO THIS PAST SATURDAY NIGHTS DROPPING SOUTHEAST ACROSS THE AREA. TEMPERATURES LOOK TO REMAIN BELOW NORMAL THIS WEEK WITH LIMITED DURATION PERIODS OF RETURN FLOW. THERE DOES STILL APPEAR TO BE A WINDOW OF ABOVE FREEZING TEMPS ON FRIDAY DEPENDING ON WHICH MODEL IS LOOKED AT...WHICH WOULD BE THE RETURN FLOW PERIOD AHEAD OF A POSSIBLE NEXT WEEKEND SYSTEM. OVERALL CONFIDENCE IS FAIRLY MINIMAL IN MOST FORECAST ELEMENTS FROM TUESDAY ONWARD. MTF && .CLIMATE... 258 PM CST THE FOLLOWING RECORDS INDICATED BY AN (*) ARE FORECAST TO BE BROKEN TONIGHT AND MONDAY: MARCH 3RD RECORD LOW MARCH 3RD RECORD LOW MAX CHICAGO: -6 (1873) 8 (1873) ROCKFORD: -4 (2002)* 18 (2002)* && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * LIGHT/VARIABLE WINDS MID-MORNING THROUGH AFTERNOON...POTENTIALLY FAVORING A NORTHEAST DIRECTION. MDB //DISCUSSION...UPDATED 06Z... HIGH PRESSURE CONTINUES TO SPREAD ACROSS THE MIDWEST AND WILL DRIFT ACROSS THE TERMINALS LATER TODAY. STEADY NORTH TO NORTH-NORTHWEST WINDS WILL EASE IN SPEED OVERNIGHT AS THE PRESSURE GRADIENT BEGINS TO SLACKEN WITH THE ARRIVAL OF THE HIGH. WINDS WILL LIKELY BECOME LIGHT AND VARIABLE BY MID MORNING OR SO INLAND OF LAKE MICHIGAN. LAKE INFLUENCES MAY BE STRONG ENOUGH TO ALLOW FOR A STEADIER NORTHEAST WIND AT MDW/GYY AND POSSIBLY ORD DESPITE THE EXTENSIVE ICE COVERAGE. SPEEDS SHOULD REMAIN UNDER 10 KT REGARDLESS OF DIRECTION/LAKE INFLUENCE. VFR WILL PREVAIL BUT THERE MAY BE FEW-SCT STRATO CU OFF THE LAKE BUT THIS SHOULD BE MINIMAL GIVEN THE DRY AIRMASS AND SUBSIDENCE ASSOCIATED WITH THE HIGH...NOT TOO MENTION THE EXTENSIVE COVERAGE OF ICE ON THE LAKE. OTHERWISE HIGH CIRRUS WITH SOME MID CLOUD COVER IS EXPECTED...ESPECIALLY GOING INTO THE EVENING. MDB //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM CONFIDENCE IN WIND DIRECTIONS MID-MORNING THROUGH AFTERNOON. * HIGH CONFIDENCE ALL OTHER ELEMENTS. MDB //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z MONDAY...UPDATED 00Z... TUESDAY THROUGH THURSDAY...MAINLY VFR WITH PERIODIC CHANCES OF LIGHT SNOW...ESPECIALLY TUESDAY/TUESDAY NIGHT. FRIDAY AND SATURDAY...CHANCE OF LIGHT RAIN OR SNOW FRIDAY AND A CHANCE OF SNOW SATURDAY. PERIODS OF MVFR/IFR POSSIBLE. RATZER && .MARINE... 129 PM CST NORTHERLY WINDS WILL CONTINUE TONIGHT...ESPECIALLY ACROSS THE SOUTHERN HALF TO TWO THIRDS OF THE LAKE...AS A STOUT AND EXPANSIVE CANADIAN HIGH PRESSURE SYSTEM CONTINUES TO BUILD FROM THE NORTHERN PLAINS ACROSS THE UPPER MIDWEST. LAKE EFFECT PROCESSES WILL LIKELY CONTINUE TO LEAD TO SMALLER SCALE DISTURBANCES MOVING SOUTHWARD DOWN THE LAKE...AND THIS WILL RESULT IN SOME LOCAL WIND DIRECTION AND SPEED DIFFERENCES ALONG THE SOUTHERN PORTIONS OF THE LAKE TONIGHT. THE WINDS WILL ABATE ON MONDAY...LIKELY BECOMING UNDER 10 KT OVER THE SOUTHERN PORTION OF THE LAKE AS THE SURFACE HIGH MOVES OVER HEAD. SEVERAL WEAK WEATHER SYSTEMS ARE EXPECTED TO AFFECT THE GREAT LAKES REGION THROUGH THE WEEK. HOWEVER...NO SIGNIFICANT WIND EVENTS ARE CURRENTLY ANTICIPATED. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WIND CHILL ADVISORY...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011 UNTIL 9 AM MONDAY. WIND CHILL ADVISORY...ILZ005-ILZ006-ILZ012-ILZ019-ILZ020 UNTIL 9 AM 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/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1112 PM CST Sun Mar 2 2014 .DISCUSSION... ISSUED 835 PM CST Sun Mar 2 2014 Storm system well to our south continues to make progress across the Southern Plains this evening. A large shield of precipitation extends northeast from the upper wave, which was located over the Panhandle of Texas. On the northern periphery of the precipitation there was mainly snow being reported over parts of south central and southeast Illinois, with a wintry mix of sleet, freezing rain and snow over extreme southern Illinois into western Ky. The bulk of the significant precip will be occurring tonight south of I70 as another sprawling Arctic air mass settles southeast into the region through Monday. Will be cancelling the northern portion of the Winter Storm warning over southeast Illinois and if precip trends continue to suggest a southeast shift in the heavier bands of snow and sleet, we may be able to cancel most if not all of the warning over the far southeast later tonight. Further to the northwest, the wind chill advisory looks fine at this point, but satellite data showing quite a bit of cirrus well off to our northwest, so that may have an affect on our early morning lows. Forecast soundings off the RAP and the latest NAM- WRF suggest the thicker cirrus shield will shift into parts of southeast Illinois by morning, so will not make any changes to the wind chill headlines for the overnight hours. After we make the adjustment to the Winter Storm Warning over the southeast counties, we will send out an updated ZFP. && .AVIATION... ISSUED 1105 PM CST Sun Mar 2 2014 VFR conditions are expected to prevail thru this forecast period. Other than a rather thick band of cirrus across central thru east central IL into the early morning hours, no significant aviation concerns are expected as high pressure builds in from the northwest. Forecast soundings indicate the cirrus will gradually work its way east of our area by Monday morning. Surface winds will be out a northerly direction at 8 to 15 kts overnight and around 10 kts during the daylight hours Monday. Smith && .PREV DISCUSSION... ISSUED 252 PM CST Sun Mar 2 2014 High pressure ridge axis over the center of the country trying to push the current storm further out of the area, but the main portion of the wave still in Arkansas. The sfc low, however, is progged to move just south of the Ohio River Valley. The storm will still produce plenty of precip issues, though most of them, including the majority of the deformation zone enhancement, will fall south of ILX this evening. Though much of the weather has ended across the northern tier of the CWA, redeveloping snow across the center of the state, and still plenty of snow/sleet/fzra mix in the southeast is keeping some of the headlines active this afternoon. Models now moving the precip out of the area a little sooner, and as long as the low continues on its forecast track SE of the forecast area, an early cancellation is anticipated. Into the rest of the forecast, the models are just fine with the overall pattern, but off with the timing of the next couple waves. These systems are not big precip makers at this point, and the forecast is mostly quiet. SHORT TERM...Tonight and Tomorrow... Winter storm wrapping up this evening, but still producing plenty of precip for the southeast. Another 1 to 3 inches of snow anticipated in the warning area, in addition to slowly transitioning sleet to snow. FA should be dry by morning. IN the meantime, temperatures dropping quickly behind the system in areas to the NW where some clearing is anticipated. Negative single digit temps North of the I-55 corridor and winds staying up in 7-15 kt range through the overnight resulting in wind chills from -15 to -20 degrees. Wind Chill Advisory is out as a result for the overnight hours and a very cold start to Monday. High pressure ridge moving closer through the day, and winds will go light and variable before switching back around to having a more southerly component. Although tomorrow night will also be cold, it will remain above zero, in the positive single digits. LONG TERM...Tuesday through Saturday... More cold air for the extended. Mon-Thursday still well below freezing. Although Friday is showing signs of a warm up, but the WAA looks a bit weak at this point. Suspicious that the MOS is being pulled too much by guidance upwards, considering that it has cooled off again with this synoptic run. Brief waves bringing quick shot of precip possibly on Wed across the north, with only slight chc pops north of I-74 corridor from GBG to PIA. ECMWF and GFS still not in agreement with the next wave btwn Thursday and Saturday night. GFS quicker and divided the energy out ahead of a trof digging in over the desert SW. GFS sends two quick shots of precip and ECMWF sends only one, along a developing baroclinic zone, while splitting the flow at 500 mb. Another pattern shift, and will likely see the models vary quite a bit as time progresses. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING until 6 AM CST Monday FOR ILZ062-063- 066>068-071>073. WIND CHILL ADVISORY until 10 AM CST Monday FOR ILZ027>031- 036>038-040>043-047>051. && $$
AREA FORECAST DISCUSSION
NWS JACKSON KY
421 AM EST MON MAR 3 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 315 AM EST MON MAR 3 2014 ...THE REST OF THE NIGHT THROUGH TODAY... ...MAJOR WINTER STORM CONTINUES THROUGH THE MORNING... 07Z SFC ANALYSIS...AND RADAR/SATELLITE IMAGERY...SHOWS A WELL DEFINED LOW PRESSURE AREA ROLLING EAST NORTHEAST THROUGH THE TENNESSEE VALLEY. THIS IS RUNNING ALONG AN ARCTIC BOUNDARY THAT CONTINUES TO SAG SOUTH THROUGH THE THIN REMAINDER OF THE STATE NOT IN THE DEEP FREEZE. THE WARM NOSE WITH THIS SYSTEM REMAINS AN ISSUE FOR MUCH OF THE AREA ALONG AND SOUTH OF THE MOUNTAIN PARKWAY...PER OBS AND THE TRANSITION SHOWING UP IN THE DOPPLER CC LOOP. A PERIOD OF FREEZING RAIN HAS BEEN DEPOSITING GENERALLY BETWEEN A TENTH TO A QUARTER OF AN INCH OF ICE BEFORE THE SLEET STARTS TO REALLY ACCUMULATE FOR MOST PLACES. REPORTS OF HALF INCH SLEET TOTALS ARE STARTING TO COME IN FROM PLACES NORTH AND WEST OF JKL. THE OFFICE IS PUSHING THAT TOTAL...AS WELL...THOUGH SOME SNOW HAS BEEN MIXING IN AT TIMES. THE STRENGTH OF THE ARCTIC AIR MASS...AND THE BAROCLINIC ZONE IT HAS LAID ACROSS EAST KENTUCKY...IS EVIDENCED BY THE MID TEENS CURRENTLY IN NORTHERN FLEMING COUNTY...LOW 20S ALONG THE WESTERN HALF OF THE MOUNTAIN PARKWAY...AND MID 30S BARELY HOLDING ON OVER THE FAR SOUTHEAST. NORTHEAST WINDS CONTINUE TO PUSH THE COLD AIR DEEPER INTO THE CWA WITH EVEN SOME GUSTS TO 15 OR 20 KTS SHOWING UP IN THE OBS CLOSER TO THE BLUEGRASS. THIS WILL ADD TO THE CONCERN FOR POWER OUTAGES AND TREE DAMAGE. ON RADAR...AN EXTENDED MASS OF PCPN REMAINS TO TRANSITION THROUGH EAST KENTUCKY WHERE IT WILL BE CONVERTED TO MAINLY SLEET AND SNOW...THOUGH FOR A TIME HEAVY RAIN AND FREEZING RAIN WILL BE POSSIBLE ACROSS THE FAR SOUTHEAST. NO CG RETURNS HAVE SHOWN UP WITH THE NORTHERN PORTION OF THIS SYSTEM IN AWHILE...BUT WOULD NOT RULE OUT SOME IN CLOUD OR CLOUD TO CLOUD BOLTS ACROSS THE AREA FOR THE NEXT SEVERAL HOURS. THE MODELS ARE IN GOOD AGREEMENT WITH THE MID LEVELS AND THE SHORTWAVE RESPONSIBLE FOR THE SFC SYSTEM GIVING US A LION OF A START TO MARCH. THIS WAVE IS CURRENTLY TRAVERSING NORTHERN ARKANSAS AND WILL ROLL NEARLY DUE EAST INTO THE SOUTHERN APPALACHIANS BY EVENING. THE MODEL AGREEMENT ALOFT DOES NOT TRANSLATE TO AGREEMENT AT THE SFC FOR A COMPLEX ONGOING SYSTEM SUCH AS THIS. SO...HAVE INSTEAD LEANED ON THE LATEST GUIDANCE FROM THE HRRR AND THE NAM12 COMBINED WITH TRENDS AND PCPN PROGRESSION TO GUIDE THE NEAR TERM FORECAST. THE HEAVY PCPN...GRADUALLY GOING TO SNOW AND FALLING AT OVER AN INCH AN HOUR...WILL MOVE THROUGH THE AREA EARLY THIS MORNING WITH A BACK EDGE AND A TAPER REACHING FAR WESTERN PARTS OF THE CWA BY 7 AM AND SWEEPING EAST BY 10 AM. HAVE USED THIS FOR TIMING THE WORST OF THE WEATHER. WILL CONTINUE THE MENTION OF THUNDER INTO THE PRE DAWN HOURS FOR THIS HEAVY PCPN BAND. THE SNOW TOTALS WILL BE LIMITED BY THE SLEET...THOUGH...SO IN A SENSE WE ARE DODGING A BULLET...BUT THE ROADS WILL TAKE THE BRUNT OF THIS STORM...AS A RESULT. THE HRRR ALSO SHOWS THE LAST OF THE DEFORMATION ZONE...BASICALLY WHAT IS GOING ON NEAR THE UPPER LOW IN SOUTHWEST MISSOURI CURRENTLY...PASSING THROUGH DURING THE EARLY AFTERNOON HOURS WITH AN ADDITIONAL INCH OR TWO OF SNOW POSSIBLE BEFORE IT TAPERS OFF AN ENDS FROM WEST TO EAST. HAVE DRAWN UP THE GRIDS WITH THESE TWO PCPN AREAS AND THEIR PROGRESS IN MIND. ACCORDINGLY...WILL HOLD ON TO THE WARNINGS AS THEY ARE WITH SOME CLEAN UP POSSIBLE TOWARD 12Z. WILL ALSO KEEP THE FLOOD WATCH AS HEAVY PCPN IN A SEMI-LIQUID FORM IS STILL EXPECTED FOR MUCH OF THAT AREA. EXPECT A GENERAL 3 TO 5 INCH SNOW AND SLEET ACCUMULATION THROUGH THE NORTHERN PART OF THE CWA WITH SLIGHTLY LESSER AMOUNTS SOUTH...BUT JUST AS MUCH SLEET...1/2 TO 1 INCH...THROUGHOUT THE ENTIRE AREA. THIS WILL BE DELINEATED FURTHER IN THE FORTHCOMING WSW UPDATES. USED THE CONSSHORT FOR TEMPERATURES...DEWPOINTS...AND WINDS...BC VERSION FOR THE LATTER TWO...THROUGH 00Z TUESDAY. ALSO DERIVED THE MAX AND MIN TEMPS FROM THE HOURLY TEMP GRIDS. AS FOR POPS...ENDED UP JUST ON THE HIGH SIDE OF ALL GUIDANCE WITH THE TAPER OF THE SNOW DURING THE DAYLIGHT HOURS TODAY. ...TONIGHT THROUGH TUESDAY... ONCE THIS SYSTEM MOVES TO THE SE OF THE REGION THIS EVENING...A STRONG MASS OF HIGH PRESSURE WILL TAKE HOLD ACROSS THE OHIO RIVER VALLEY...WITH UPPER LEVEL RIDGING FINALLY TAKING SHAPE ACROSS MUCH OF THE CONUS. THIS SET UP SHOULD KEEP KY DRY FOR THE NEXT 24 HOURS...AS WELL AS USHER IN DRY CANADIAN AIR INTO THE REGION. WITH THE PASSAGE OF THE COLD FRONT...AND THIS PUSH OF COLDER...DRIER CANADIAN AIR...EXPECT LOWS TO DROP DOWN WELL BELOW NORMAL ONCE MORE TONIGHT. OVERNIGHT LOWS ARE ONLY EXPECTED TO BE IN THE SINGLE DIGITS ABOVE ZERO ACROSS THE NORTHERN CWA...TO THE LOW TEENS IN THE SOUTHERN COUNTIES. WITH THE FRONTAL SYSTEM THAT JUST PASSED THROUGH...WINDS WERE GUSTY IN MANY LOCATIONS. LUCKILY...EXPECT THESE WINDS TO DIE DOWN BY TONIGHT. THIS WILL HAVE GOOD AND BAD IMPLICATIONS. ON THE DOWN SIDE...LIGHTER WINDS...IN ADDITION TO CLEAR SKIES AND A COOLER AIR MASS OVERHEAD...WILL PROVIDE OPTIMAL RADIATIONAL COOLING...HENCE THE EXPECTED OVERNIGHT LOW TEMPS. ON THE UP SIDE...WITH TEMPERATURES EXPECTED TO DROP THIS LOW...ANY AMOUNT OF WIND WILL ONLY AID TO THE WIND CHILL FACTOR...MAKING CONDITIONS FEEL EVEN COLDER THAN THEY REALLY ARE. THAT BEING SAID...WINDS WILL NOT BE NIL. WE CAN EXPECT LIGHT WINDS IN THE 3 TO 7 KT RANGE...WHICH WILL STILL BE ENOUGH TO DROP WIND CHILL READINGS DOWN INTO THE SINGLE DIGITS BELOW ZERO ACROSS THE NORTH. COLD AIR WILL CONTINUE TO FILTER IN DURING THE DAY TUESDAY...BUT HIGHER SUN ANGLES FOR MARCH...AND AN ABUNDANT AMOUNT OF SUNSHINE WITH THIS DRY AIR MASS IN PLACE...THIS WILL HELP TEMPERATURES TO BOUNCE BACK TO JUST ABOVE FREEZING IN THE NORTH...AND POSSIBLY INTO THE LOW 40S ACROSS THE FAR SOUTHEAST COUNTIES. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 421 AM EST MON MAR 3 2014 A SURFACE HIGH PRESSURE RIDGE OVER THE REGION WILL BE BREAKING DOWN AT THE START OF THE PERIOD...BUT DRY AIR WILL STILL BE IN PLACE AND THEIR WILL BE NO SIGNIFICANT UPPER LEVEL FEATURES THROUGH AT LEAST WEDNESDAY...SO THE WEATHER WILL REMAIN UNEVENTFUL. ON WEDNESDAY NIGHT...AN AMPLIFYING TROUGH WILL BE DROPPING SE TOWARD THE LOWER MISSISSIPPI VALLEY. MODELS ARE NOW LESS INCLINED TO CLOSE OFF A MID/UPPER LEVEL LOW WITH THIS SYSTEM...AND AS A RESULT THEY ARE MORE PROGRESSIVE WITH IT. SURFACE DEVELOPMENT IS STILL INDICATED OVER THE GULF...BUT IT TRACKS FURTHER EAST THAN IN RUNS OF RECENT DAYS. AS A RESULT...IT IS LOOKING LESS LIKELY THAT WE WILL SEE DIRECT EFFECTS FROM THE CYCLOGENESIS. HOWEVER...THE MID/UPPER LEVEL TROUGH COULD BRING SOME LIGHT RAIN ON THURSDAY OR THURSDAY EVENING AS IT PASSES. A TRANSITORY RIDGE AT THE SURFACE AND ALOFT WILL THEN MOVE THROUGH ON FRIDAY AND FRIDAY NIGHT...WITHOUT ANY COOLING IN THE WAKE OF THE DEPARTING SYSTEM. ANOTHER LARGE SCALE MID/UPPER LEVEL TROUGH AND ITS ASSOCIATED COLD FRONT ARE EXPECTED TO HEAD IN FROM THE NW DURING THE WEEKEND. GFS AND ECMWF AGREE ON THE BIG PICTURE FOR THIS...BUT SHOW SOME TIMING DIFFERENCES. TAKING BOTH INTO CONSIDERATION...THE MOST LIKELY TIME FOR PRECIP WILL BE SATURDAY NIGHT. WITH THE UNCERTAINTY...HAVE KEPT POPS IN THE CHANCE CATEGORY EVEN FOR SATURDAY NIGHT...WITH A BUFFER OF LOWER POPS ON BOTH SIDES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1227 AM EST MON MAR 3 2014 DETERIORATING CONDITIONS CAN BE EXPECTED FOR MOST LOCATIONS THROUGH MONDAY...AS A SIGNIFICANT STORM SYSTEM CONTINUES ACROSS EASTERN KENTUCKY...BRINGING RAIN...FREEZING RAIN...SLEET...AND SNOW TO THE AREA. EXPECT IFR TO LIFR OR WORSE CONDITIONS...ESPECIALLY AS THE TRANSITION TO SNOW BEGINS...WHICH WILL BEGAN AROUND 04Z FOR THE FAR NORTH...AND CLOSER TO 11 TO 12Z FOR THE FAR SOUTH. CONDITIONS WILL BEGIN TO IMPROVE FROM NORTHWEST TO SOUTHEAST TOWARDS MID DAY ON MONDAY. AVIATION INTERESTS ALOFT WILL NEED TO CONSIDER SIGNIFICANT ICING UNTIL ALL PRECIPITATION CAN CHANGE TO SNOW. THE HEAVIEST PRECIPITATION COULD ALSO HAVE CONVECTIVE TURBULENCE AND LIGHTNING. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR KYZ044- 050>052. WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR KYZ058>060-068-069-104-106>109-111-112-114. FLOOD WATCH UNTIL 7 AM EST THIS MORNING FOR KYZ068-069-079-080- 083>088-107-109-110-112>120. WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR KYZ079-080- 083>088-110-113-115>120. && $$ SHORT TERM...GREIF/JMW LONG TERM...HAL AVIATION...DUSTY
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
315 AM EST MON MAR 3 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 315 AM EST MON MAR 3 2014 ...THE REST OF THE NIGHT THROUGH TODAY... ...MAJOR WINTER STORM CONTINUES THROUGH THE MORNING... 07Z SFC ANALYSIS...AND RADAR/SATELLITE IMAGERY...SHOWS A WELL DEFINED LOW PRESSURE AREA ROLLING EAST NORTHEAST THROUGH THE TENNESSEE VALLEY. THIS IS RUNNING ALONG AN ARCTIC BOUNDARY THAT CONTINUES TO SAG SOUTH THROUGH THE THIN REMAINDER OF THE STATE NOT IN THE DEEP FREEZE. THE WARM NOSE WITH THIS SYSTEM REMAINS AN ISSUE FOR MUCH OF THE AREA ALONG AND SOUTH OF THE MOUNTAIN PARKWAY...PER OBS AND THE TRANSITION SHOWING UP IN THE DOPPLER CC LOOP. A PERIOD OF FREEZING RAIN HAS BEEN DEPOSITING GENERALLY BETWEEN A TENTH TO A QUARTER OF AN INCH OF ICE BEFORE THE SLEET STARTS TO REALLY ACCUMULATE FOR MOST PLACES. REPORTS OF HALF INCH SLEET TOTALS ARE STARTING TO COME IN FROM PLACES NORTH AND WEST OF JKL. THE OFFICE IS PUSHING THAT TOTAL...AS WELL...THOUGH SOME SNOW HAS BEEN MIXING IN AT TIMES. THE STRENGTH OF THE ARCTIC AIR MASS...AND THE BAROCLINIC ZONE IT HAS LAID ACROSS EAST KENTUCKY...IS EVIDENCED BY THE MID TEENS CURRENTLY IN NORTHERN FLEMING COUNTY...LOW 20S ALONG THE WESTERN HALF OF THE MOUNTAIN PARKWAY...AND MID 30S BARELY HOLDING ON OVER THE FAR SOUTHEAST. NORTHEAST WINDS CONTINUE TO PUSH THE COLD AIR DEEPER INTO THE CWA WITH EVEN SOME GUSTS TO 15 OR 20 KTS SHOWING UP IN THE OBS CLOSER TO THE BLUEGRASS. THIS WILL ADD TO THE CONCERN FOR POWER OUTAGES AND TREE DAMAGE. ON RADAR...AN EXTENDED MASS OF PCPN REMAINS TO TRANSITION THROUGH EAST KENTUCKY WHERE IT WILL BE CONVERTED TO MAINLY SLEET AND SNOW...THOUGH FOR A TIME HEAVY RAIN AND FREEZING RAIN WILL BE POSSIBLE ACROSS THE FAR SOUTHEAST. NO CG RETURNS HAVE SHOWN UP WITH THE NORTHERN PORTION OF THIS SYSTEM IN AWHILE...BUT WOULD NOT RULE OUT SOME IN CLOUD OR CLOUD TO CLOUD BOLTS ACROSS THE AREA FOR THE NEXT SEVERAL HOURS. THE MODELS ARE IN GOOD AGREEMENT WITH THE MID LEVELS AND THE SHORTWAVE RESPONSIBLE FOR THE SFC SYSTEM GIVING US A LION OF A START TO MARCH. THIS WAVE IS CURRENTLY TRAVERSING NORTHERN ARKANSAS AND WILL ROLL NEARLY DUE EAST INTO THE SOUTHERN APPALACHIANS BY EVENING. THE MODEL AGREEMENT ALOFT DOES NOT TRANSLATE TO AGREEMENT AT THE SFC FOR A COMPLEX ONGOING SYSTEM SUCH AS THIS. SO...HAVE INSTEAD LEANED ON THE LATEST GUIDANCE FROM THE HRRR AND THE NAM12 COMBINED WITH TRENDS AND PCPN PROGRESSION TO GUIDE THE NEAR TERM FORECAST. THE HEAVY PCPN...GRADUALLY GOING TO SNOW AND FALLING AT OVER AN INCH AN HOUR...WILL MOVE THROUGH THE AREA EARLY THIS MORNING WITH A BACK EDGE AND A TAPER REACHING FAR WESTERN PARTS OF THE CWA BY 7 AM AND SWEEPING EAST BY 10 AM. HAVE USED THIS FOR TIMING THE WORST OF THE WEATHER. WILL CONTINUE THE MENTION OF THUNDER INTO THE PRE DAWN HOURS FOR THIS HEAVY PCPN BAND. THE SNOW TOTALS WILL BE LIMITED BY THE SLEET...THOUGH...SO IN A SENSE WE ARE DODGING A BULLET...BUT THE ROADS WILL TAKE THE BRUNT OF THIS STORM...AS A RESULT. THE HRRR ALSO SHOWS THE LAST OF THE DEFORMATION ZONE...BASICALLY WHAT IS GOING ON NEAR THE UPPER LOW IN SOUTHWEST MISSOURI CURRENTLY...PASSING THROUGH DURING THE EARLY AFTERNOON HOURS WITH AN ADDITIONAL INCH OR TWO OF SNOW POSSIBLE BEFORE IT TAPERS OFF AN ENDS FROM WEST TO EAST. HAVE DRAWN UP THE GRIDS WITH THESE TWO PCPN AREAS AND THEIR PROGRESS IN MIND. ACCORDINGLY...WILL HOLD ON TO THE WARNINGS AS THEY ARE WITH SOME CLEAN UP POSSIBLE TOWARD 12Z. WILL ALSO KEEP THE FLOOD WATCH AS HEAVY PCPN IN A SEMI-LIQUID FORM IS STILL EXPECTED FOR MUCH OF THAT AREA. EXPECT A GENERAL 3 TO 5 INCH SNOW AND SLEET ACCUMULATION THROUGH THE NORTHERN PART OF THE CWA WITH SLIGHTLY LESSER AMOUNTS SOUTH...BUT JUST AS MUCH SLEET...1/2 TO 1 INCH...THROUGHOUT THE ENTIRE AREA. THIS WILL BE DELINEATED FURTHER IN THE FORTHCOMING WSW UPDATES. USED THE CONSSHORT FOR TEMPERATURES...DEWPOINTS...AND WINDS...BC VERSION FOR THE LATTER TWO...THROUGH 00Z TUESDAY. ALSO DERIVED THE MAX AND MIN TEMPS FROM THE HOURLY TEMP GRIDS. AS FOR POPS...ENDED UP JUST ON THE HIGH SIDE OF ALL GUIDANCE WITH THE TAPER OF THE SNOW DURING THE DAYLIGHT HOURS TODAY. ...TONIGHT THROUGH TUESDAY... ONCE THIS SYSTEM MOVES TO THE SE OF THE REGION THIS EVENING...A STRONG MASS OF HIGH PRESSURE WILL TAKE HOLD ACROSS THE OHIO RIVER VALLEY...WITH UPPER LEVEL RIDGING FINALLY TAKING SHAPE ACROSS MUCH OF THE CONUS. THIS SET UP SHOULD KEEP KY DRY FOR THE NEXT 24 HOURS...AS WELL AS USHER IN DRY CANADIAN AIR INTO THE REGION. WITH THE PASSAGE OF THE COLD FRONT...AND THIS PUSH OF COLDER...DRIER CANADIAN AIR...EXPECT LOWS TO DROP DOWN WELL BELOW NORMAL ONCE MORE TONIGHT. OVERNIGHT LOWS ARE ONLY EXPECTED TO BE IN THE SINGLE DIGITS ABOVE ZERO ACROSS THE NORTHERN CWA...TO THE LOW TEENS IN THE SOUTHERN COUNTIES. WITH THE FRONTAL SYSTEM THAT JUST PASSED THROUGH...WINDS WERE GUSTY IN MANY LOCATIONS. LUCKILY...EXPECT THESE WINDS TO DIE DOWN BY TONIGHT. THIS WILL HAVE GOOD AND BAD IMPLICATIONS. ON THE DOWN SIDE...LIGHTER WINDS...IN ADDITION TO CLEAR SKIES AND A COOLER AIRMASS OVERHEAD...WILL PROVIDE OPTIMAL RADIATIONAL COOLING...HENCE THE EXPECTED OVERNIGHT LOW TEMPS. ON THE UP SIDE...WITH TEMPERATURES EXPECTED TO DROP THIS LOW...ANY AMOUNT OF WIND WILL ONLY AID TO THE WIND CHILL FACTOR...MAKING CONDITIONS FEEL EVEN COLDER THAN THEY REALLY ARE. THAT BEING SAID...WINDS WILL NOT BE NIL. WE CAN EXPECT LIGHT WINDS IN THE 3 TO 7 KT RANGE...WHICH WILL STILL BE ENOUGH TO DROP WIND CHILL READINGS DOWN INTO THE SINGLE DIGITS BELOW ZERO ACROSS THE NORTH. COLD AIR WILL CONTINUE TO FILTER IN DURING THE DAY TUESDAY...BUT HIGHER SUN ANGLES FOR MARCH...AND AN ABUNDANT AMOUNT OF SUNSHINE WITH THIS DRY AIRMASS IN PLACE...THIS WILL HELP TEMPERATURES TO BOUNCE BACK TO JUST ABOVE FREEZING IN THE NORTH...AND POSSIBLY INTO THE LOW 40S ACROSS THE FAR SOUTHEAST COUNTIES. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 531 PM EST SUN MAR 2 2014 AS THE LONG TERM PERIOD STARTS...DEPENDING ON HOW LONG A SHALLOW MIXED MOIST LAYER AT TEMPS AROUND -10C SHOULD NOT YIELD ANYTHING MORE THAN A FEW FLURRIES ON MONDAY EVENING...IF THAT. SURFACE COOLING COUPLED WITH WEAK WARMING JUST OFF THE SURFACE SHOULD PUT AND END TO FLURRIES DURING THE NIGHT. IT STILL APPEARS THAT COLD HIGH PRESSURE PASSING BY TO OUR NORTH WILL GIVE US MAINLY CLEAR SKIES BY LATE MONDAY NIGHT INTO TUESDAY MORNING. LOWS SHOULD DROP INTO THE SINGLE DIGITS NORTH AND IN SOME VALLEY LOCATIONS FURTHER SOUTH PENDING TIMING OF CLEARING AND PRESSURE GRADIENT AS FRESH SNOW COVER SHOULD LEAD TO MORE EFFICIENT RADIATIONAL COOLING. THE VERY DRY AIR MASS WHICH THIS HIGH PUTS IN PLACE SHOULD KEEP USE DRY AT LEAST THROUGH AT LEAST EARLY ON THURSDAY...DESPITE A COUPLE OF WEAK MID/UPPER LEVEL SHORTWAVES PASSING THROUGH ON TUE INTO TUE NIGHT. UPPER LEVEL RIDGING AND HEIGHT RISES SHOULD DOMINATE ON WEDNESDAY. THE NEXT SHOT AT PRECIP DOES NOT APPEAR TO BE UNTIL THURSDAY. BOTH THE GFS AND ECMWF IN GENERAL CONTINUE TO HAVE AN UPPER LEVEL TROUGH DROPPING TOWARD THE GULF COAST FROM WED INTO WED NIGHT AND THEN POSSIBLY FORMING A CLOSED LOW BY THU. SURFACE DEVELOPMENT ENSUES IN THE NORTHERN GULF OF MEXICO AND HEADS NE ALONG THE SE COAST. WITH A HIGH AMPLITUDE MID/UPPER SYSTEM FORECAST TO POSSIBLY CLOSE OFF FOR A TIME...CONFIDENCE FOR TIMING AND TRACK IS NOT HIGH AT THIS TIME RANGE THOUGH THE 12Z GFS AND 12Z ECMWF AS WELL AS THE 18Z GFS HAVE THE SFC AND UPPER LEVEL SYSTEM TRACKING TOO FAR SOUTH AND EAST FOR MUCH MORE THAN THE TN AND OR VA BORDER COUNTIES BEING BRUSHED WITH AN INCREASE IN MOISTURE AND POSSIBLY A LITTLE BIT OF LIGHT PRECIPITATION. HOW QUICKLY THE SE CONUS SYSTEM DEPARTS WILL PLAY A ROLE IN HOW QUICKLY ANOTHER SYSTEM CAN MOVE IN FROM THE NW. THE GFS AND ECMWF STILL DO NOT AGREE ON THE TIMING FROM MODEL RUN TO MODEL RUN AND FROM MODEL TO MODEL...AND A GENERALIZED FORECAST CONSENSUS BLEND WHICH LED TO A LONG PERIOD OF SLIGHT CHANCE TO CHANCE POPS FROM LATE FRI NIGHT INTO SUNDAY HAS BEEN USED. THE 12Z GFS WOULD SUPPORT FRI NIGHT INTO SAT CHANCES FOR RAIN OR LIGHT PRECIPITATION WHILE THE 12Z ECMWF AND THE 0Z ECMWF FOR THAT MATTER HAVE THE SHORTWAVE AND SFC BOUNDARY MOVING INTO THE AREA NEARLY 24 HOURS LATE FOR SAT NIGHT INTO SUNDAY. AFTER SOME VERY COLD READINGS FOR EARLY MARCH...TEMPERATURES SHOULD MODERATE A BIT ON ON TUESDAY INTO THE 30S TO LOWER 40S. WITH THE ANTICIPATED SNOW COVER WE HAVE CONTINUED TO UNDERCUT MOS GUIDANCE FOR TUESDAY. TUE NIGHT SHOULD AGAIN BE CHILLY BUT WARMER THAN MONDAY NIGHT. TEMPERATURES SHOULD AVERAGE BELOW NORMAL THROUGH THE PERIOD...BUT WILL MODERATE TO CLOSER TO NORMAL BY THE SECOND HALF OF THE WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1227 AM EST MON MAR 3 2014 DETERIORATING CONDITIONS CAN BE EXPECTED FOR MOST LOCATIONS THROUGH MONDAY...AS A SIGNIFICANT STORM SYSTEM CONTINUES ACROSS EASTERN KENTUCKY...BRINGING RAIN...FREEZING RAIN...SLEET...AND SNOW TO THE AREA. EXPECT IFR TO LIFR OR WORSE CONDITIONS...ESPECIALLY AS THE TRANSITION TO SNOW BEGINS...WHICH WILL BEGAN AROUND 04Z FOR THE FAR NORTH...AND CLOSER TO 11 TO 12Z FOR THE FAR SOUTH. CONDITIONS WILL BEGIN TO IMPROVE FROM NORTHWEST TO SOUTHEAST TOWARDS MID DAY ON MONDAY. AVIATION INTERESTS ALOFT WILL NEED TO CONSIDER SIGNIFICANT ICING UNTIL ALL PRECIPITATION CAN CHANGE TO SNOW. THE HEAVIEST PRECIPITATION COULD ALSO HAVE CONVECTIVE TURBULENCE AND LIGHTNING. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR KYZ044- 050>052. WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR KYZ058>060-068-069-104-106>109-111-112-114. FLOOD WATCH UNTIL 7 AM EST THIS MORNING FOR KYZ068-069-079-080- 083>088-107-109-110-112>120. WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR KYZ079-080- 083>088-110-113-115>120. && $$ SHORT TERM...GREIF/JMW LONG TERM...JP AVIATION...DUSTY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1121 PM CST SUN MAR 2 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 430 PM CST SUN MAR 2 2014 ...RECORD OR NEAR-RECORD LOW TEMPERATURES AROUND DAYBREAK TOMORROW IN THE COLDEST START TO MARCH SINCE 2002 AND ONE OF THE COLDEST STARTS ON RECORD... ALOFT: MODESTLY SPLIT LOW-AMPLITUDE FLOW WAS OVER THE CONUS WITH A SHORTWAVE TROF MOVING E THRU CO/NM INTO INCREASINGLY CONFLUENT FLOW. THIS TROF WILL HEAD E ACROSS THE SRN PLAINS AND INTO THE SE STATES TONIGHT. AS THIS OCCURS...HEIGHTS WILL RISE OVER THE WRN USA. HOWEVER...THE NEXT SHORTWAVE TROF IS MOVING ONSHORE INTO OR/NRN CA THIS AFTERNOON. THE MOST INTENSE PORTION OF THIS TROF WILL MISS THE REGION FAR TO THE NW...BUT A LOW-AMPLITUDE PV STREAMER WILL MOVE THRU TOMORROW...WEAKENING AS IT MOVES THRU THE RIDGE. SURFACE: ELONGATED AND UNSEASONABLY STRONG HIGH PRES EXTENDED FROM WRN CANADA S INTO THE PLAINS. THIS HIGH WILL SHRINK AND SLOWLY WEAKEN AS IT DRIFTS INTO THE MIDWEST TONIGHT...AND INTO THE GREAT LAKES TOMORROW. THIS HIGH AND CLOUD COVER WILL PLAY MAJOR ROLES IN HOW COLD TEMPS GET TONIGHT. BREAKING/SETTING RECORD LOWS IS ON THE TABLE. REST OF THIS AFTERNOON: CLOUDY BUT SOME IMPROVEMENT WILL ENCROACH FROM THE N OF NEB HWY 92. SOME LIGHT SNOW /-SN/ MAY DEVELOP OVER PARTS OF S-CNTRL NEB. TEMPS DID GET ABOVE THE ALL-TIME RECORD COLDEST FOR THE MONTH OF MARCH...BUT NOT BY MUCH. PLEASE SEE THE CLIMATE SECTION FOR ADDITIONAL INFO ON RECORDS. TONIGHT: UNSEASONABLE BITTER COLD! IF OUR TEMPS WORK OUT AS FCST... LOWS WILL BE NEARLY 40F COLDER THAN WHERE THEY TYPICALLY ARE FOR EARLY MARCH /LOW-MID 20S/. THE PASSAGE OF THE TROF TONIGHT WILL RESULT IN A DECREASING CLOUDS. SOME MULTI-LAYERED MID-HIGH CLOUDS ARE UPSTREAM OVER WY...BUT THEY WILL BE MOVING INTO SUBSIDENCE. SO AM NOT EXPECTING SKIES TO COMPLETELY CLEAR...BUT IT SHOULD BE ENOUGH TO INFLICT A MAJOR IMPACT ON TEMPS. THE SURFACE RIDGE AXIS WILL MIGRATE ACROSS THE FCST AREA AS WELL... RESULTING IN SEVERAL HOURS OF CALM OR NEARLY CALM WINDS. TEMPS: LOWS WERE -13 TO -20 OVER THE DAKOTA`S THIS MORNING. AND WHILE THERE IS SNOWCOVER UP THERE...MOST OF IT IS A WEEK OLD. THE OTHER THING TO CONSIDER IS THE MAGNITUDE OF THIS AIR MASS. THE 850 MB TEMP WAS -21C AT GRAND ISLAND THIS MORNING. BASED ON REANALYSIS DATA...-21 AND COLDER HAS ONLY OCCURRED 4 TIMES IN THE PAST 34 YRS. AND GIVEN THAT TEMPS WILL ONLY BE ABOVE FRZG FOR ABOUT 5 HRS TODAY ALONG AND N OF HWY 6...I BELIEVE WE NEED TO FCST RECORD COLD. DEWPOINTS ARE ALSO IN THE NEGATIVE TEENS OVER MUCH OF S-CNTRL NEB. LOW TEMPS WERE DROPPED 4-7F FROM THE PREVIOUS FCST. A WIND CHILL /WC/ ADVISORY WAS ISSUED FOR MOST OF THE FCST AREA. FROM THE TRI-CITIES N AND E...A WARNING WAS ISSUED FOR 1-2 HRS OF -30 TO -35 WC`S IN THE 6AM-9AM TIMEFRAME. JUST AS TEMPS BOTTOM OUT...WINDS WILL BEGIN TO INCREASE AND THIS WILL HAPPEN DURING THE MORNING RUSH. SNOW: A NICE BAROCLINIC LEAF HAS DEVELOPED ON SATELLITE WITH A BLOSSOMING AREA OF DEFORMATION -SN OVER WRN KANSAS. THIS HAS DEVELOPED FURTHER N THAN THE 12Z NAM-DERIVED HI-RES MODELS FCST. THE 17Z HRRR HAS IT AND BELIEVE THERE IS A WINDOW OF OPPORTUNITY FOR A TOUCH OF -SN OVER PARTS OF N-CNTRL KS...ESPECIALLY FROM STOCKTON-OSBORNE-BELOIT SOUTHWARD. A CHANCE OF -SN IS NOW IN THE FCST. THE MID-LEVEL CIRCULATION IS FCST TO DROP ESE WHICH WILL ACTUALLY DRAG THE SNOW SHIELD AWAY FROM N-CNTRL KS AS SUNSET APPROACHES. TOMORROW: HIGH CLOUDS WILL ALREADY BE MOVING IN AT DAWN ASSOCIATED WITH THE WEAK UPPER TROF. SO OVERALL EXPECT A PARTLY SUNNY AND BLUSTERY DAY. HOW QUICKLY TEMPS WARM UP IS UNCERTAIN. SO CONFIDENCE IN THE HOURLY TEMPS IS BELOW AVERAGE. WENT ABOVE NEARLY ALL GUIDANCE ON WIND SPEEDS. AS A LEE-SIDE TROF DEVELOPS...THE PRES GRADIENT WILL INCREASE TO 16 MB ACROSS NEB. THE GFS/EC/NAM/SREF HAVE A 30-35 KT LOW-LEVEL JET MAX AND BELIEVE WE WILL TAP INTO THE UNDERSIDE OF IT. MIXING HEIGHTS ARTIFICIALLY TOO LOW...ESPECIALLY ON THE NAM WHICH HAS ITS SNOWCOVER BIAS. EVEN IF WE USE THE CONSERVATIVE GFS MIXING HEIGHTS AROUND 2K FT...THAT STILL WOULD ALLOW FOR MIXING DOWN 30 KTS. HIGH TEMPS WERE RAISED 2-4F FROM THE PRIOR GID FCST...ALONG AND W OF HWY 281. POST MORTEM: LAST NIGHT`S SNOW RISK OVER CNTRL/NRN KS ENDED UP CONSIDERABLY LESS THAN WHAT THE MODELS DEPICTED. THESE TYPE OF SITUATIONS THAT ARE DRIVEN BY JET STREAK AND FRONTAL FORCING /IN THE MID-LEVELS/ ARE INCREDIBLY DIFFICULT TO FCST. THERE IS NO LOW PRES FROM WHICH WE DERIVE OUR TRADITIONAL FCST CUES. THESE ISOLATED NARROW SNOW BANDS HAVE VERY LOW PREDICTABILITY. THE HI-RES MESOSCALE MODELS DEPICT THEM VERY WELL /WHEN AND IF THEY ARE CORRECT/. YOU CAN THROW OUT THE SYNOPTIC SCALE MODELS. THEY CANT HANDLE THESE SMALL FEATURES AND ARE WAYYYY TO BROAD WITH THEIR QPF. THE BAND DID DEVELOP BUT IT WAS MODELED TO BECOME STATIONARY ALONG/NEAR I-70 WHICH IT DID NOT. IT WAS TRANSIENT. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 430 PM CST SUN MAR 2 2014 ALTHOUGH THERE HAVE BEEN NO MAJOR CHANGES TO THE FORECAST DURING THIS TIME FRAME OVER THE PAST 12-24 HOURS...AS IS TYPICAL SEVERAL PERIODS HAD HIGH/LOW TEMPS TWEAKED UPWARD OR DOWNWARD AS MUCH AS 2-5 DEGREES...BUT THE OVERALL THEME OF A TRANSITION TO MILDER WEATHER REMAINS INTACT. THAT BEING SAID...ITS NOT NECESSARILY GOING TO BE A CASE WHERE EACH DAY GETS PROGRESSIVELY WARMER...AS DAYS SUCH AS WEDNESDAY...FRIDAY AND POSSIBLY SATURDAY COULD END UP BEING EITHER SMALL OR POTENTIALLY LARGER BUMPS IN THE ROAD. MEANWHILE...BOTH THURSDAY AND VERY PRELIMINARILY NEXT SUNDAY BOTH LOOK LIKE THE BEST CANDIDATES FOR THE MILDEST DAYS OF THE NEXT 7 WITH ABOVE NORMAL READINGS BETWEEN THE UPPER 40S-LOW 60S. PRECIPITATION-WISE...THE MAJORITY OF THIS 6-DAY PERIOD SHOULD BE DRY...BUT 20-30 POPS CONTINUE FOR ALL OR PARTS OF THE CWA ON TUESDAY NIGHT-WEDNESDAY AND FRIDAY NIGHT...AND A NEW SLIGHT CHANCE HAS BEEN ADDED TO NORTHERN ZONES FRIDAY DAYTIME...MAKING NOW A TOTAL OF 4 PERIODS MENTIONING SOME RISK OF MEASURABLE PRECIP. NEEDLESS TO SAY...UNCERTAINTY REMAINS HIGH IN BOTH OF THESE WINDOWS OF OPPORTUNITY FOR PRECIPITATION...INCLUDING THE TUES NIGHT-WED POSSIBILITY. FOR ONLY BEING A FEW DAYS AWAY...ITS STILL TOUGH TO SAY WHETHER 1) THERE IS EVEN MUCH CHANCE OF MEASURABLE PRECIP AT ALL AND HENCE POPS KEPT LOW THUS FAR AND 2) IF PRECIP DOES FALL...WHAT TYPE WILL IT ASSUME? KEEPING WITH THE REASONING DISCUSSED HERE 24 HOURS AGO...HAVE KEPT ANY TUES-NIGHT WED PRECIP TYPE AS SNOW OR RAIN/SNOW FOR NOW...BUT THERE CONTINUES TO BE SIGNS IN SOME FORECAST SOUNDINGS THAT AT LEAST A BRIEF PERIOD OF SLEET/SOME TYPE OF WINTRY MIX COULD COME INTO PLAY HERE AS WELL. GIVEN TIME IS STILL ON OUR SIDE HERE WITH THIS POSSIBLE ROUND OF PRECIP STILL BEING 48+ HOURS AWAY...WILL KEEP THE BASIC TYPES FOR NOW AND AVOID CLUTTERING THE FORECAST WITH TOO MUCH UNCERTAINTY AND/OR CAUSING UNDUE CONCERN AS THE MENTION OF MIXED-PHASE WINTRY TYPES CAN SOMETIMES DO. AS FOR POTENTIAL SNOWFALL AMOUNTS WITH ANY TUES NIGHT/WEDNESDAY PRECIP...ITS OBVIOUSLY WAY TOO EARLY TO TALK SPECIFICS WITH MUCH CONFIDENCE...BUT GIVEN THAT IT IS WITHIN 72 HOURS OF NOW HAVE TOSSED A VERY GENERIC COVERAGE OF AMOUNTS RANGING FROM A DUSTING UP TO AROUND 1 INCH INTO THE OFFICIAL SNOWFALL GRIDS. THE SAME SNOW OR RAIN/SNOW PRECIP TYPE ROUTE WAS USED WITH THE FRIDAY-FRIDAY NIGHT POPS...ALTHOUGH THE LATEST ECMWF WOULD SUGGEST THIS WOULD PROBABLY BE MORE OF A TRUE SNOW EVENT WITH LESS RISK OF MIXED-TYPES SHOULD IT OCCUR. GETTING INTO MORE DETAIL AND STARTING WITH MONDAY NIGHT...CONFIDENCE IS PRETTY HIGH IN DRY CONDITIONS WITH ONLY SOME PASSING MID-HIGH LEVEL CLOUDS AS THE CENTRAL PLAINS REMAINS UNDER A BROAD WEST-NORTHWEST FLOW REGIME ALOFT THAT DEFINES MUCH OF THE CONUS. THERE ARE SOME HINTS THAT SOME LOWER STRATUS COULD DEVELOP AND STREAM NORTHWARD INTO PARTS OF THE CWA IN LOW LEVEL SOUTHERLY FLOW...BUT AM NOT SOLD ON THIS SCENARIO SO SKY COVER IS GENERALLY AIMED INTO PARTLY CLOUDY TERRITORY FOR NOW. SOUTHERLY BREEZES OF AT LEAST 5-10 MPH WILL PREVAIL THROUGH THE NIGHT...AND AS A RESULT LOW TEMPS SHOULD REMAIN CONSIDERABLY HIGHER THAN THOSE ON MONDAY MORNING BUT STILL WELL BELOW NORMAL. MADE LITTLE CHANGE TO THESE VALUES...STILL AIMING FOR MOST OF THE CWA TO BOTTOM OUT SOMEWHERE BETWEEN 9-14 ABOVE ZERO. FOR TUESDAY DAYTIME THROUGH WEDNESDAY NIGHT...THE OVERALL STORY IN THE MID-UPPER LEVELS INVOLVES THE GRADUAL EAST-SOUTHEASTWARD DEVELOPMENT OF A PROGRESSIVE SHORTWAVE TROUGH THAT MOVES FROM THE PACIFIC COAST INTO THE CENTRAL AND ESPECIALLY SOUTHERN PLAINS...AMPLIFYING AS IT DOES SO. WITH THE MAIN BATCH OF FORCING STILL WEST OF THE AREA DURING THE DAY TUESDAY HAVE KEPT IT DRY...AND EVEN RAISED TEMPS 2-4 DEGREES GIVEN CONTINUED SOUTHERLY FLOW AHEAD OF A COLD FRONT THAT STARTS TO DROP INTO NORTHERN ZONES IN THE AFTERNOON. ASSUMING THAT CLOUDS ARE NOT OVERLY ABUNDANT...ITS POSSIBLE THAT ADVERTISED HIGHS RANGING FROM MID 30S NORTHEAST TO MID 40S SOUTHWEST MAY NOT BE WARM ENOUGH...BUT ITS ALSO WORTH NOTING THAT THE HIGHS ADVERTISED BY THE LAST FEW NAM RUNS APPEAR WAY TOO COLD. TUESDAY NIGHT INTO WEDNESDAY...MODEL TIMING DIFFERENCES GROW...BUT VARIOUS MODELS INCLUDING THE NAM/GFS/ECMWF BRING AT LEAST LIGHT PRECIP OF AT LEAST SOME VARIETY INTO THE AREA BEFORE MOVING IT OUT BY WEDNESDAY NIGHT. THE MILLION DOLLAR QUESTION IS HOW STRONG THE SYNOPTIC FORCING/FRONTOGENESIS WILL BE WITH THIS WAVE OVER THE LOCAL AREA...AS THAT WILL ULTIMATELY SPELL THE DIFFERENCE BETWEEN LEGITIMATE LIGHT MEASURABLE AMOUNTS SUCH AS DEPICTED BY THE NAM AND OTHER MODELS...OR ESSENTIALLY NOTHING WHATSOEVER AS ADVERTISED BY THE 12Z GEM MODEL. THE PRESENCE OF PRECIP OR LACK THEREOF WILL ALSO AFFECT HIGHS WED...AND WITH CONFIDENCE BEING LOW OPTED TO MAKE LITTLE CHANGE TO PREVIOUS WITH GENERALLY MID-UPPER 30S. THURSDAY DAYTIME THROUGH FRIDAY NIGHT...THIS LOOKS TO FEATURE A BRIEF PERIOD OF SHORTWAVE RIDGING ALOFT BEFORE GIVING WAY TO THE NEXT POTENTIAL TROUGH MOVING IN FROM THE WEST-NORTHWEST. AS A RESULT...A BIT OF A TEMPERATURE ROLLER-COASTER STARTS TO DEVELOP. WITH INCREASING SOUTHERLY FLOW/GOOD WARM AIR ADVECTION GOING AHEAD OF THIS DISTURBANCE ON THURS...THIS SHOULD BE THE WARMEST DAY IN AWHILE...AND MADE LITTLE CHANGE TO HIGHS WITH A RANGE FROM UPPER 40S-UPPER 50S. THEN FROM FRIDAY INTO FRIDAY NIGHT...A POTENTIALLY FAIRLY STRONG COLD FRONT IS SLATED TO DROP THROUGH THE AREA...AND AS A RESULT FRIDAY HIGHS WERE LOWERED 3-5 DEGREES...BUT STILL UPPER 30S NORTH TO UPPER 40S SOUTH FOR NOW. AS EARLIER MENTIONED...SLIGHT POPS MAINLY FOR FRIDAY NIGHT ACCOMPANY THE PASSAGE OF THIS SHORTWAVE TROUGH...WHICH COULD BRING A QUICK SHOT OF LIGHT SNOW PER THE LATEST ECMWF BUT LESS-SO THE GFS. SATURDAY THROUGH SUNDAY...CONFIDENCE IS REASONABLY HIGH IN A RETURN TO DRY CONDITIONS FOR THE WEEKEND ASSUMING THAT FRIDAY NIGHT PRECIP MOVES OUT BY SATURDAY DAYTIME...AS THE PATTERN ALOFT AGAIN TRANSITIONS TO RIDGING. MADE LITTLE CHANGE TO SATURDAY HIGHS WITH A RANGE OF 40S ACROSS THE AREA...BUT THE LATEST ECMWF IS COOLER THAN THIS. VERY PRELIMINARILY...SUNDAY IS LOOKING LIKE THE OUTRIGHT-WARMEST DAY OF THE ENTIRE FORECAST...AND FOR NOW HAVE WIDESPREAD 50S IN NEB ZONES AND LOW 60S IN KS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1120 PM CST SUN MAR 2 2014 A SURFACE HIGH TO THE EAST WILL ALLOW FOR LIGHT WINDS DURING THE NIGHT. DURING THE MORNING...THE SURFACE HIGH WILL MOVE OFF TO THE EAST. WINDS WILL TURN TO THE SOUTH AND AS THE PRESSURE GRADIENT TIGHTENS...THE WINDS WILL INCREASE DURING THE AFTERNOON HOURS. && .CLIMATE... ISSUED AT 1146 AM CST SUN MAR 2 2014 IT IS EXTREMELY DIFFICULT TO GET HIGH TEMPS IN THE SINGLE DIGITS IN MARCH. IT HAS ONLY HAPPENED 5 TIMES EVER AT GRAND ISLAND AND HASTINGS. VULNERABLE LOW TEMP RECORDS TODAY: GRAND ISLAND: -5 IN 1960 (TIED) HASTINGS: -5 IN 1913 (TIED) * BOTH OF THESE RECORDS CAN BE BROKEN IF TEMPS DROP BELOW -5F BEFORE MIDNIGHT. VULNERABLE COLDEST DAILY HIGH TEMP RECORDS TODAY: GRAND ISLAND: 10 IN 2002 (CURRENT FORECAST HIGH: 7) HASTINGS: 11 IN 2002 (CURRENT FORECAST HIGH: 7) VULNERABLE LOW TEMP RECORDS FOR TOMORROW 3/3: GRAND ISLAND: -16 IN 1960 HASTINGS: -10 IN 1960 ALL-TIME COLDEST HIGH TEMPS FOR THE ENTIRE MONTH OF MARCH: GRAND ISLAND: 4 ON 3/10/1948 HASTINGS: 3 ON 3/11/1948 && .GID WATCHES/WARNINGS/ADVISORIES... NE...WIND CHILL WARNING UNTIL 10 AM CST MONDAY FOR NEZ039>041-046>049- 061>064-073>076. WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NEZ060-072-077- 082>087. KS...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR KSZ005>007- 017>019. && $$ SHORT TERM...HALBLAUB LONG TERM...PFANNKUCH AVIATION...JCB CLIMATE...HALBLAUB
AREA FORECAST DISCUSSION
NWS NORMAN OK
1024 PM CST SUN MAR 2 2014 .AVIATION... SNOW WILL EXIT NORTHERN OKLAHOMA BEFORE 3 AM LEAVING MVFR CEILINGS AND DECREASING NORTH WINDS BEHIND. GUSTY NORTH WINDS IN GENERAL WILL DIMINISH BEFORE SUNRISE AND BECOME RELATIVELY LIGHT AFTER DAYBREAK. CEILINGS WILL RISE ABOVE MVFR CATEGORY BY LATE MORNING. && .PREV DISCUSSION... /ISSUED 937 PM CST SUN MAR 2 2014/ UPDATE... UPPER LOW CONTINUES TO MOVE EAST ACROSS OKLAHOMA. THE DRY SLOT WRAPPING AROUND THE LOW HAS EFFECTIVELY ENDED SIGNIFICANT PRECIPITATION ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS... ALTHOUGH THERE IS STILL SOME LIGHT PRECIPITATION BEING REPORTED IN PORTIONS OF SOUTH CENTRAL/SOUTHEAST OKLAHOMA DESPITE THE LACK OF RADAR ECHOES. FARTHER NORTH... THE PRECIPITATION CONTINUES WITH SOME RECENT REDEVELOPMENT OBSERVED IN WEST CENTRAL OKLAHOMA. MAY STILL SEE SOME ACCUMULATING SNOW IN NORTH CENTRAL OKLAHOMA UNDERNEATH THE PIVOT POINT OF THE PRECIPITATION BANDS IN THE NORTH. WILL KEEP THE CURRENT WARNING IN PLACE IN THE NORTH AT THIS TIME /ALTHOUGH WE HAD WHITTLED AWAY AT THE HEADLINES EARLIER THIS EVENING/. PREV DISCUSSION... /ISSUED 603 PM CST SUN MAR 2 2014/ AVIATION... THE LAST BAND OF SLEET AND SNOW WILL MOVE EAST OF CENTRAL OKLAHOMA BY MIDNIGHT. MVFR CEILINGS WILL BE WIDESPREAD UNTIL MONDAY AFTERNOON. GUSTY NORTH WIND WILL GRADUALLY DIMINISH BY LATE MORNING MONDAY. PREV DISCUSSION... /ISSUED 245 PM CST SUN MAR 2 2014/ DISCUSSION... A MULTI-FACETED WINTER WEATHER MESS CONTINUES TO AFFECT OKLAHOMA AND NORTH TEXAS. WV SATELLITE SHOWS A FAIRLY IMPRESSIVE UPPER LEVEL STORM SYSTEM DEEPENING ACROSS THE TX/OK PANHANDLES...WITH WELL PRONOUNCED DRY SLOT ENTERING WRN OK...AND AREA OF DEFORMATION/BANDED SNOW OVER THE OK/TX PANHANDLES. AHEAD OF THIS AREA OF MID LEVEL DRY AIR...SCT SNOW/SLEET SHOWERS ALONG WITH CONVECTIVE ELEMENTS CONTAINING HAIL CONTINUE. INSTABILITY REMAINS TOO MARGINAL FOR SEVERE HAIL...BUT SEVERAL REPORTS OF DIMES AND NICKELS HAVE COME IN. EXPECT THE LIKLIHOOD OF HAIL TO WANE THROUGH LATE AFTERNOON...BUT HEAVY SLEET CAN BE EXPECTED WITH ANY BOOMERS THAT HAPPEN TO AFFECT YOUR LOCATION. IN FACT...SLEETFALL RATES OF ONE HALF TO ONE INCH PER HOUR ARE PROBABLE WITH THE STRONGEST CONVECTIVE CORES. HOWEVER...THESE RATES WILL GENERALLY BE FEW AND FAR BETWEEN...AND EXPECT LIGHT TO MODERATE SLEET AND SNOW TO PERSIST INTO TONIGHT. THE HIGH-RES HRRR CONTINUES TO SUGGEST PERHAPS THE HEAVIEST SLEET WILL FALL OVER EXTREME SOUTH CENTRAL AND SOUTHEAST OKLAHOMA LATE THIS AFTERNOON AND EVENING...AND CONFIDENCE IN MORE WIDESPREAD HALF INCH OR GREATER SLEET ACCUMULATIONS IN THIS AREA WARRANTED A WINTER STORM WARNING. AREAS OF CENTRAL AND SOUTHWESTERN OKLAHOMA...AND WESTERN NORTH TEXAS HAVE CERTAINLY SEEN SLEET AND SNOW ACCUMULATIONS...BUT CONFIDENCE IS LOW THAT WSW CRITERIA WILL BE MET ON A LARGE SCALE...THUS WILL MAINTAIN THE ADVISORY FOR NOW. FARTHER NORTH AND WEST OVER NORTHWESTERN AND NORTH-CENTRAL OKLAHOMA HAVE THE BETTER CHANCES OF SUBSTANTIAL SNOW ACCUMULATIONS. HAVE OPTED TO MAINTAIN CURRENT WINTER STORM WARNING IN THESE AREAS...THOUGH SEVERAL MODELS HAVE SHIFTED THE HEAVIER SNOW SLIGHTLY FARTHER SOUTH...AND WILL HAVE TO KEEP A CLOSE EYE ON RADAR TRENDS AND OBSERVATIONS. THE STORM SYSTEM SHOULD GRADUALLY WORK EAST OF THE AREA OVERNIGHT TONIGHT...BUT SOME LINGERING LIGHT SNOW WILL LIKELY CARRY INTO THE WEE MORNING HOURS TOMORROW. ONCE WE GET TO SUNRISE TOMORROW...THE MAIN STORY WILL BE THE BITTERLY COLD TEMPERATURES AND WIND CHILLS. SINGLE DIGIT TO NEAR ZERO LOWS ARE FORECAST OVER A GOOD PART OF OKLAHOMA...WITH LOWER TEENS OVER SOUTHERN OKLAHOMA AND NORTH TEXAS. THIS COMBINED WITH NORTH WINDS WILL RESULT IN WIND CHILLS FROM NEAR ZERO SOUTH TO -15 DEGREES NORTH. THUS...HAVE ISSUED A WIND CHILL ADVISORY FOR MUCH OF OKLAHOMA. HIGHS WILL STRUGGLE INTO THE 20S AND 30S TOMORROW...SO DON`T EXPECT A LOT OF MELTING. ROAD CONDITIONS WILL LIKELY REMAIN SLICK AND HAZARDOUS RIGHT THROUGH TOMORROW AFTERNOON. ONCE WE GET THROUGH TOMORROW...THINGS ARE LOOKING UP. YES...IT WILL STILL BE CHILLY WEDNESDAY...BUT THE OVERALL TREND IS POSITIVE AS FAR AS TEMPS GO. MODELS BRING A WEAK UPPER WAVE OVER THE SOUTHERN PLAINS SOMETIME WEDNESDAY OR WEDNESDAY NIGHT...ANY PRECIP THAT ACCOMPANIES THIS SHOULD MAINLY FALL IN LIQUID FORM...THOUGH PARTS OF NORTHERN OKLAHOMA MAY GET A RAIN/SNOW MIX. TEMPERATURES WILL THEN WARM EACH DAY THROUGH LATE WEEK...WITH ANOTHER SHOT OF COLD AIR JUST IN TIME FOR NEXT WEEKEND. WELCOME TO WINTER IN MARCH EVERYONE! && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 7 24 17 46 / 50 0 10 10 HOBART OK 5 27 18 49 / 30 0 10 0 WICHITA FALLS TX 12 32 22 50 / 10 0 10 10 GAGE OK -2 25 19 48 / 60 0 10 0 PONCA CITY OK 3 20 13 41 / 100 0 10 0 DURANT OK 13 28 23 46 / 30 0 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR OKZ013- 017>020-023>032-040>043-046>048-050>052. WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR OKZ004>036-038- 040-042. WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR OKZ004>008- 010>012. TX...NONE. && $$ 26/09/09
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
349 AM CST MON MAR 3 2014 .DISCUSSION... AREA OF LARGELY FREEZING RAIN/SLEET CONTINUES TO MOVE ACROSS THE MID-STATE THIS MORNING WITH SFC LOW NOW APPALACHIANS VICINITY AND SFC TEMPS SUB-FREEZING TO NEAR THE AL BORDER. BACK EDGE MOVING EAST PRETTY RAPIDLY AND HAS AROUND THE PLATEAU. GFS/ECM LITTLE SLOW WITH ADVANCEMENT OF PCPN. 06Z NAM/LATEST HRRR BLOWING HEAVY FREEZING PCPN OFF THE PLATEAU SHORTLY SEEMINGLY MORE REASONABLE GIVEN LATEST OBSERVATION DATA. WARM NOSE CURRENTLY STILL AROUND H9-H7 EXPECTED SCOUR OUT OF ALL EXCEPT PLATEAU BY 12Z...THEN THERE AROUND 15Z. EXPECT BREAK IN PCPN TO CONTINUE FOR A SHORT TIME EARLY THIS MORNING BUT REFIRE 11Z-18Z OR SO AS SNOW WHILE UL LOW/TROUGH PASSES. POTENTIAL FOR HEAVIEST SNOWFALL MOST LIKELY ACROSS PARTS OF THE NORTH AND IT SEEMS THERE IS NOT MUCH IN THE WAY OF ACCUMULATION SOUTH. THERE HAS BEEN GOOD AMOUNT OF ICE ACCUMULATION NORTH/WEST OF NASHVILLE AND THERE IS THE POSSIBILITY OF 1-3 INCH SNOWFALL THAT MAY AGGRAVATE SITUATION. AMOUNT OF SNOWFALL LARGELY LOOKS AT OR BELOW 1 INCH SOUTH. THUS WITH CURRENT AND FCST TRENDS...HAVE ADJUSTED WARNINGS/ADVISORIES. PCPN ENDS LATER THIS AFTERNOON AND THAT WILL LEAVE THE AREA IN A DRY SPELL UNTIL AN UPPER LOW AND WEAK FRONT BRING A FEW SHOWERS TO THE AREA ON THU. WEAK RIDGING ON FRI WILL BE QUICKLY FOLLOWED BY ANOTHER WEAK FRONT/UPPER TROUGH LATER SAT INTO EARLY SUN. THIS COULD BRING ANOTHER ROUND OF SHOWERS THROUGH THAT PERIOD. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 28 18 42 27 / 100 10 10 10 CLARKSVILLE 25 11 37 19 / 100 10 10 10 CROSSVILLE 28 16 46 28 / 100 10 10 10 COLUMBIA 31 18 44 29 / 90 10 10 10 LAWRENCEBURG 31 21 46 29 / 60 10 10 10 WAVERLY 26 11 40 20 / 100 10 10 10 && .OHX WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR TNZ010- 011-031>034-064>066. WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR TNZ058- 060-061-063-075-077-093>095. WINTER STORM WARNING UNTIL NOON CST TODAY FOR TNZ005>009-023>030- 056-057-059-062. WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR TNZ078>080. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1038 PM CST SUN MAR 2 2014 .DISCUSSION...SEE 06Z AVIATION DISCUSSION. && .AVIATION...WINDS NOT AS STRONG AS GUIDANCE SUGGESTS...AND TIME HEIGHTS INDICATE CIGS MAY IMPROVE A FEW HOURS EARLIER AS WELL. THUS...MADE THOSE ADJUSTMENTS TO THE TERMINALS. CIGS ALREADY AT MVFR AT KVCT AND KLRD...AND SHOULD REMAIN SO...WITH IFR CIGS IMPROVING TO MVFR BEFORE 12Z. EXPECTING VFR CIGS AT KVCT AND KLRD SHORTLY AFTER SUNRISE (AOA 13Z)...WITH VFR CIGS AT KALI AND KCRP ABOUT 16Z. SHOULD HAVE VFR CIGS REST OF TERMINAL FORECAST. GOING A BIT LOWER ON WINDS BUT STILL GUSTY THROUGH THE MORNING ALL TERMINAL (AND MAINLY NORTH)...WITH DIMINISHING WINDS BY MID AFTERNOON ALL TERMINALS. FINALLY...PUT A TEMPO IN FOR -RA AT KALI AND KCRP BASED ON RADAR BUT EXPECTING ACTIVITY TO WANE. && .PREV DISCUSSION... /ISSUED 935 PM CST SUN MAR 2 2014/ DISCUSSION...THE STRONG COLD FRONT HAS PUSHED THROUGH THE CWA THIS EVENING RESULTING IN STRONG GUSTY N WINDS AND FALLING TEMPS. BASED ON THE LATEST TEMP TRENDS AND HOW FAST THEY ARE FALLING AND DUE TO SEVERAL MODELS PROGING FREEZING TEMPS ACROSS THE NRN PORTIONS OF THE CWA...HAVE FOLLOWED SUIT AND LOWERED MN TEMPS BY A FEW DEGREES RESULTING IN A LIGHT FREEZE ACROSS THE NRN CWA AND MORE WIDESPREAD WIND CHILL VALUES BELOW 25 DEGREES. THEREFORE HAVE EXPANDED THE WIND CHILL ADVISORY TO INCLUDE ALL OF THE CWA INCLUDING THE EASTERN PORTIONS OF WEBB AND LA SALLE COUNTIES. ALSO ISSUING A SPECIAL WEATHER STATEMENT TO ADDRESS THE BRIEF LIGHT FREEZING TEMPS. PREV DISCUSSION... /ISSUED 659 PM CST SUN MAR 2 2014/ DISCUSSION...STRONG COLD FRONT IS MOVING THROUGH THE CWA A LITTLE FASTER BY A COUPLE OF HOURS THAN PREVIOUSLY ANTCIPATED. HAVE UPDATED FCST TO ACCOUNT FOR THE FASTER FROPA AND WENT EARLIER WITH THE SMALL CRAFT ADVISORY FOR THE BAYS. WINDS BEHIND THE FROPA HAVE BEEN INITIALLY GUSTING BETWEEN 30-40 KNOTS THEN DECREASING TO 28-35KTS...THEREFORE AM NOT ANTCIPATING WIND ADVISORY CONDITIONS AT THIS TIME. HOWEVER...WIND CHILL ADVISORY FOR THE VICTORIA CROSSROADS REMAINS IN EFFECT. ISOLD SHRA`S HAVE ALSO BEEN DVLPG ALONG AND BEHIND THE FRONT...BUT IS EXPECTED TO DIMINISH OVERNIGHT FROM NW TO SE. SOME MODELS PROG MN TEMPS OF 31 DEGREES AROUND VCT BUT THINK CLOUD COVER AND STRONG WINDS WILL KEEP MN TEMPS JUST ABV FREEZING BUT A BRIEF DIP TO 32 DEGREES AROUND SUNRISE ACROSS A FEW LOCATIONS ACROSS THE NRN CWA IS NOT OUT OF THE QUESTION. ONLY MADE TWEAKS TO TEMPS/DEWPOINTS/WSHFT TO ACCOUNT FOR THE FASTER FROPA. PREV DISCUSSION... /ISSUED 548 PM CST SUN MAR 2 2014/ DISCUSSION...SEE 00Z AVIATION DISCUSSION. AVIATION...ONCE THE FRONT COMES THROUGH (WHICH IS VERY EARLY IN THE FORECAST)...CIGS WILL FALL TO IFR AT KCRP...KVCT AND KALI BUT BE MVFR AT KLRD. CIGS WILL FALL RAPIDLY AT THE EASTERN TERMINALS...BUT MAY TAKE A BIT OF TIME AT KLRD (BASED ON SATELLITE AND GUIDANCE). FRONT ALREADY THROUGH KVCT AND SHOULD BE THROUGH REMAINDER OF TERMINALS BY 02Z (AND PROBABLY EARLIER). SOME SHOWERS ALONG BOUNDARY EXPECTED...BUT THUNDER UNLIKELY BASED ON CAP WHICH IS EXPECTED TO HOLD THUNDER IN CHECK. RATHER WINDY TONIGHT WITH SUSTAINED WINDS AOA 20 KNOTS AND GUSTS AOA 30 KNOTS...BUT NOT AS STRONG AT KLRD. CONDITIONS IMPROVE TO MVFR...THEN VFR (BUT STILL CIGS) DURING THE DAY ON MONDAY. WINDS AND GUSTS FINALLY TAPER OFF DURING THE AFTERNOON. PREV DISCUSSION... /ISSUED 413 PM CST SUN MAR 2 2014/ SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...VERY STRONG COLD FRONT IS KNOCKING ON THE DOOR ACROSS THE NORTHERN ZONES. FRONT SHOULD ENTER THE AREA IN AN HOUR OR TWO AND MOVE THROUGH THE REMAINDER OF THE REGION THIS EVENING. ONLY SOME LIGHT SHOWERS HAVE DEVELOPED THIS FAR OVER THE NORTHEAST ZONES...WITH NO THUNDER REPORTED YET. THINK LOW CHANCES FOR SHOWERS WILL EXIST ALONG OF AND BEHIND THE FRONT THROUGH THE FIRST PART OF THE EVENING. TEMPERATURES WILL BEGIN TO TUMBLE BEHIND THE FRONT AND SOME LOCATIONS MAY BE ABOUT 40 TO 45 DEGREES COOLER MONDAY MORNING COMPARED TO RIGHT NOW. IN ADDITION TO THE COLDER TEMPS...STRONG WINDS WILL DEVELOP TONIGHT ESPECIALLY OVER THE COASTAL COUNTIES. QUITE A SPREAD IN GUIDANCE EXISTS BETWEEN MAV/MET WIND SPEEDS WITH THE MAV SUGGESTING WIND ADVISORY CONDITIONS. TEMPERED WIND SPEEDS A BIT BUT WINDY CONDITIONS WILL DEVELOP NONETHELESS WITH SPEEDS BETWEEN 20 AND 30 MPH. A WIND ADVISORY COULD BECOME NECESSARY IF SPEEDS ARE A LITTLE HIGHER. WIND CHILLS WILL BE AN ISSUE THOUGH OVER THE NORTHERN COASTAL BEND AND VICTORIA CROSSROADS REGION WHERE WC VALUES WILL FALL BETWEEN 20 AND 25 AFTER MIDNIGHT. HAVE ISSUED A WIND CHILL ADVISORY FOR THESE LOCATIONS. SOMETHING ALSO WORTH MONITORING WILL BE THE PRECIP CHANCES AFTER MIDNIGHT...AS THE LAST FEW HOURS OF THE HRRR HAS DEVELOPED PRECIP OVER MUCH OF SOUTH TEXAS. CONFIDENCE IS LOWER ON THIS SCENARIO...BUT HAVE KEPT SOME LOW POPS OVER THE SOUTHERN AND EASTERN AREAS. CLOUDY CONDITIONS AND NORTHERLY WINDS WILL KEEP TEMPERATURES DOWN IN THE 40S ON MONDAY. PRECIP CHANCES WILL RAMP BACK UP ON MONDAY NIGHT AS 850MB FLOW TURNS SOUTHERLY AND ISENTROPIC LIFT PATTERN BECOMES ESTABLISHED. MARINE...VERY STRONG OFFSHORE WINDS WILL DEVELOP OVER THE GULF WATERS BEHIND A COLD FRONT. GUSTS TO GALE FORCE BETWEEN 35 AND 40 KNOTS WILL BE LIKELY AND HAVE ISSUED A GALE WARNING OVER THE NEARSHORE AND OFFSHORE WATERS. SEAS WILL BUILD BETWEEN 6 AND 8 FEET OVER THE NEARSHORE WATERS AND 8 TO 10 FEET OVER THE OFFSHORE WATERS BY MONDAY MORNING. WIND SPEEDS WILL DIMINISH BY MID MORNING ON MONDAY BUT STILL REMAIN IN SMALL CRAFT ADVISORY LEVELS THROUGH THE AFTERNOON. LONG TERM (TUESDAY THROUGH SUNDAY)...S/W TROUGH AXIS WILL KICK EAST DURING THE DAY TUESDAY WITH DAYTIME PRECIP MAINLY CONFINED TO EASTERN ZONES AND DURING THE MORNING HOURS. AN INCREASE IN NVA SHOULD LIMIT PRECIP DURING THE AFTERNOON AND EARLY EVENING HOURS BEFORE SLIGHT CHANCES RETURN AFTER MIDNIGHT ACROSS EASTERN ZONES AS ANOTHER S/W TROUGH SKIRTS EAST ACROSS TX. THIS SYSTEM IS PROG TO BE A LITTLE FARTHER NORTH AND A LITTLE MORE MOISTURE STARVED THAN MON NIGHT/TUESDAY SYSTEM...AND THUS ONLY A SLIGHT CHANCE OF LIGHT PRECIP IS EXPECTED AT THIS TIME. NW FLOW FROM SFC TO UPPER LEVELS ON THURSDAY SHOULD LEAD TO SUNNIER AND DRIER CONDITIONS AREAWIDE. BRIEF ZONAL FLOW ALOFT ON FRIDAY TRANSITIONS TO MERIDIONAL BY THE WEEKEND WITH BOTH ECMWF/GFS WANTING TO BRING ANOTHER COLD FRONT INTO THE REGION. GUIDANCE IS ALSO WANTING TO CUT OFF A STRONG H5 LOW ACROSS NW MEX AND SHIFT IT EAST TOWARDS THE BIG BEND REGION. HAVE INCREASED POPS FOR LATTER PERIODS DUE TO INCREASED CONFIDENCE IN SEEING SOME PRECIP ACROSS THE AREA AS LOW PROGRESSES CLOSER. MAX TEMPS WILL REMAIN WELL BELOW NORMAL FOR TUES WITH ONLY TEMPERED MODIFICATION ON WEDNESDAY. MORE SUBSTANTIAL WARM UP EXPECTED THURS AND FRIDAY AND INTO SATURDAY BEFORE ANOTHER COLD FRONT POTENTIALLY IMPACTS THE AREA LATE IN THE LONG TERM PERIOD. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 35 47 38 44 44 / 30 20 50 50 20 VICTORIA 33 47 36 42 41 / 30 10 50 50 20 LAREDO 38 46 39 52 47 / 10 10 20 10 10 ALICE 35 46 38 45 43 / 20 10 40 40 20 ROCKPORT 33 48 39 45 45 / 30 20 50 50 20 COTULLA 36 49 37 48 44 / 10 10 30 10 10 KINGSVILLE 35 45 38 46 44 / 30 20 50 50 20 NAVY CORPUS 37 46 41 45 45 / 30 20 50 50 20 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...WIND CHILL ADVISORY UNTIL 9 AM CST MONDAY FOR THE FOLLOWING ZONES: ARANSAS...BEE...CALHOUN...DUVAL...GOLIAD...JIM WELLS...KLEBERG...LA SALLE...LIVE OAK...MCMULLEN...NUECES... REFUGIO...SAN PATRICIO...VICTORIA...WEBB. GM...SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. GALE WARNING UNTIL 9 AM CST MONDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM... COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. SMALL CRAFT ADVISORY UNTIL 6 PM CST MONDAY FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS... BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR. && $$ GW/86...AVIATION
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1142 PM CST SUN MAR 2 2014 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 230 PM CST SUN MAR 2 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH PRESSURE CENTERED ACROSS THE NORTHERN GREAT PLAINS. TEMPERATURES REMAIN COLD EARLY THIS AFTERNOON WITHIN THE HIGH...WITH READINGS A FEW DEGREES ON EITHER SIDE OF THE ZERO DEGREE MARK. WIND CHILL VALUES REMAIN IN THE TEENS BELOW ZERO AT MANY LOCATIONS OVER EAST- CENTRAL/CENTRAL/NORTH-CENTRAL WISCONSIN. OTHER THAN THE UNSEASONABLY COLD CONDITIONS...SKIES ARE MAINLY CLEAR ACROSS MUCH OF MINNESOTA AND WISCONSIN...THOUGH CIRRUS FROM A SOUTHERN STREAM STORM SYSTEM IS CROSSING THE BORDER INTO SOUTHERN WISCONSIN. OTHER LOW STRATUS IS DRIFTING SOUTH TOWARDS THE NORTHERN SHORELINE OF LAKE SUPERIOR. WITH THE SOUTHERN STORM SYSTEM EXPECTED TO REMAIN WELL SOUTH OF THE REGION...TEMPS AND WIND CHILLS ARE THE MAIN FOCUS AS THE ARCTIC HIGH MOVES EAST TONITE. TONIGHT...ARCTIC HIGH PRESSURE WILL SHIFT SOUTHEAST FROM THE NORTHERN GREAT PLAINS INTO THE NORTHERN MISSISSIPPI VALLEY. BOTH THE NAM AND GFS SHOW THE MOISTURE THAT IS APPROACHING NORTHERN LAKE SUPERIOR DRYING UP AS IT RUNS INTO THE VERY DRY ARCTIC AIRMASS. WILL CONTINUE TO SHOW FEW TO SCT SKY CONDITIONS THIS EVENING ACROSS FAR NORTHERN WISCONSIN IN CASE A LITTLE MOISTURE IS PICKED UP OFF LAKE SUPERIOR. LIKE YESTERDAY...THE NAM IS DEVELOPING A LAKE INDUCED SURFACE TROUGH UP THE SPINE OF LAKE MICHIGAN LATE TONIGHT. AS A RESULT...MAY SEE SCT LAKE CLOUDS MOVE JUST INLAND ALONG THE LAKE MICHIGAN SHORELINE. CONFIDENCE IS NOT HIGH ENOUGH TO ADD FLURRIES INTO THE FORECAST...BUT COULD SEE THAT HAPPENING. THE OTHER ISSUE IS TEMPS/WIND CHILL HEADLINES. THE PRESSURE GRADIENT TIGHTENS BRIEFLY THIS EVENING AND THEN SLACKENS OVERNIGHT WITH THE APPROACHING SURFACE HIGH. CONDITIONS ARE MORE SUPPORTIVE OF DECOUPLING THAN LAST NIGHT AND WILL SHOW THAT TREND OCCURRING MAINLY AFTER 06Z. THIS MAKES FOR A DILEMMA IN REGARDS TO WIND CHILL HEADLINES...WHICH REQUIRE AT 3 KTS OF WIND. THINK THERE COULD BE A FEW HOUR PERIOD OF WIND CHILL CRITERIA BEING MET BEFORE WINDS BECOME CALM WITH VALUES FALLING BETWEEN 20 TO 30 BELOW. TOUGH TO GET EXCITED ABOUT HEADLINES WITH SUCH A SHORT DURATION EVENT...EVEN THOUGH THE CALM WINDS WILL PROMOTE TANKING TEMPERATURES. AFTER COLLAB WITH SURROUNDING OFFICES...DECIDED TO ISSUE WIND CHILLS HEADLINES TO KEEP THE MAP PRETTY. THE MIDNIGHT CREW CAN CANCEL EARLY IF DESIRED. DROPPED LOWS BY PERHAPS A DEGREE IN SPOTS. MONDAY...THE ARCTIC HIGH PRESSURE WILL DRIFT TO THE SOUTHERN GREAT LAKES. LOW LEVEL TEMPS WILL MODERATE AS SURFACE WINDS SHIFT TO THE SOUTHWEST IN THE AFTERNOON. UNDER PLENTY OF SUN...TEMPS SHOULD RISE INTO THE LOWER TEENS. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 230 PM CST SUN MAR 2 2014 NEAR ZONAL FLOW EXPECTED MUCH OF THIS PERIOD WITH TEMPERATURES... WHILE REMAINING BELOW NORM...MODERATE FROM WHAT WE HAVE TODAY. PATTERN AMPLIFIES SOME TOWARD THE WEEKEND WITH RIDGE REBUILDING OVER THE WEST COAST AND TROFFING SETTING UP AGAIN OVER CENTRAL U.S. IN LATER PERIODS FEATURE TO WATCH...SIG SHORT WAVE MOVING THROUGH CENTRAL CANADA. THIS SYSTEM AND FOLLOW ON WEAKER WAVES TO PUSH COLD FRONT THROUGH STATE OVER THE WEEKEND WITH CHANCE FOR PCPN THROUGH PERIOD. GULF MOISTURE NOT A PLAYER...SO AMOUNTS EXPECTED TO BE LIGHT. TEMPERATURES EXPECTED TO DROP BACK INTO LOW TO MID 20S. IN NEAR TERM...TWO PERIODS OF LIGHT SNOW EXPECTED MON NIGHT INTO TUE AND AGAIN TUE EVENING. SHORTWAVES COMBINE WITH WEAK WAA AND JET ENERGY THESE PERIODS...WITH TUE NIGHT SYSTEM AFFECTING MAINLY SOUTH PART OF CWA. FOR MON NIGHT MODELS HAVE BEEN CONSISTENT YESTERDAY AND TODAY WITH CROSS SECTIONS SHOWING WEAK LIFT THROUGH DEEP AREA OF GOOD DENDRICTIC GROWTH RATES. HAVE BUMPED SNOW ACCUMULATIONS UP GIVEN EXPECTED 20 TO 1 SNOW RATIOS. A GOOD INCH TO UP TO TWO INCHES EXPECTED LATE MON NIGHT INTO TUE MORNING. DRY HIGH PRESSURE EXPECTED TO SINK SOUTH INTO NORTHERN WI LATE TUE NIGHT...WED MORN...CLEARING SKIES OUT WED. LIGHT NORTHEAST TO EAST WINDS EXPECTED WILL BRING SMALL CHANCE FOR MAINLY LAKE EFFECT FLURRIES. LATEST VISIBLE SAT IMAGERY TODAY OF LAKE MI SHOWING LIMITED OPEN WATER...SO WILL NOT PUT INTO GRIDS AT THIS TIME. GFS STILL ODD MODEL OUT BEING QUICKER WITH NEXT PLAINS SYSTEM BRINGING PCPN INTO REGION WED NIGHT. HAVE STAYED WITH MAJORITY WITH SLOWER TIMING. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1141 PM CST SUN MAR 2 2014 CLEAR SKIES AND LIGHT WINDS EXPECTED TONIGHT. MIDDLE AND HIGH CLOUDS WILL ARRIVE MONDAY BUT IT WILL REMAIN VFR THROUGH THE DAY. LIGHT SNOW WILL MOVE IN FROM WEST TO EAST DURING THE LATE EVENING HOURS AND DIMINISH TUESDAY MORNING WITH MVFR OR IFR CEILINGS AND VISIBILITIES. AN INCH OR TWO OF LIGHT AND FLUFFY SNOW ARE LIKELY IN MOST PLACES. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY UNTIL 9 AM CST MONDAY FOR WIZ013-020>022-031- 037>040-045-048>050-073-074. WIND CHILL ADVISORY UNTIL 9 AM CST MONDAY FOR WIZ005-010>012-018- 019-030-035-036. && $$ SHORT TERM.....MPC LONG TERM......TE AVIATION.......RDM
AREA FORECAST DISCUSSION
NWS RENO NV
625 AM PST MON MAR 3 2014 .UPDATE... RADAR IMAGERY SHOWS PCPN IN NRN CA GETTING CLOSE TO THE CWA THIS MORNING. WEB CAM AT BOGARD REST AREA IN WESTERN LASSEN COUNTY INDICATES WET PAVEMENT. THE PCPN IS LIKELY LIGHT ENOUGH RIGHT NOW TO BE MISSED BY RADAR. IN ANY EVENT PCPN IS MOVING IN AND THIS IS A BIT FASTER THAN ORIGINALLY FORECAST. HAVE UPDATED TO INCREASE POPS OVER THE NW CWA THIS MORNING. SNOW LEVELS SHOULD REMAIN HIGH FOR A WHILE RESULTING IN ONLY ACCUMULATIONS IN THE FAR WESTERN PORTION OF LASSEN COUNTY JUST EAST OF LASSEN PARK. IT IS LIKELY THAT POPS WILL NEED TO BE RAISED A BIT MORE TODAY OVER THE NORTH. ALSO BUMPED UP QPF A LITTLE...MORE IN LINE WITH THE 09 UTC SREF. 20 && .PREVIOUS DISCUSSION... /ISSUED 329 AM PST MON MAR 3 2014/ SYNOPSIS... A BAND OF SUBTROPICAL PACIFIC MOISTURE WILL BRING AREAS OF RAIN AND HIGH ELEVATION SNOW TO THE SIERRA AND WESTERN NEVADA LATER TODAY AND TONIGHT. MORE RAIN AND SNOW IS LIKELY IN THE SIERRA AND NORTHEAST CALIFORNIA BY WEDNESDAY NIGHT AS ANOTHER FAST MOVING LOW PRESSURE MOVES THROUGH. LATER THIS WEEK, DRY WEATHER WILL RETURN. ABOVE NORMAL TEMPERATURES ARE EXPECTED THROUGH THE UPCOMING WEEK. SHORT TERM... WATER VAPOR SATELLITE LOOP SHOWS A RATHER IMPRESSIVE BAND OF PACIFIC MOISTURE EXTENDING FROM HAWAII TO THE CENTRAL CA COAST. PRECIPITABLE WATER VALUES APPROACH 1.5 INCHES NEAR THE WEST COAST. HOWEVER, DESPITE THIS DECENT AMOUNT OF MOISTURE, FORCING IS LIMITED WHICH WILL LIMIT PRECIPITATION INTENSITY EAST OF THE SIERRA CREST AND INTO WESTERN NV THROUGH TONIGHT. WHILE THE 00Z MODEL GUIDANCE FAVORED THE BEST CHANCE FOR RAIN AND HIGH ELEVATION SNOW FOR LATER TONIGHT, THE 06Z GFS AND RECENT HRRR RUNS SPREAD MORE AREAS OF LIGHT PRECIP ACROSS THE REGION DURING THE DAY, WITH A GRADUAL SOUTHWARD PUSH TONIGHT. SNOW LEVELS ARE CURRENTLY PROJECTED TO RANGE FROM 6500 TO 7000 FEET, BUT GIVEN THE SUBTROPICAL AND EVEN TROPICAL ORIGIN OF THIS MOISTURE PLUME, THEY COULD RISE 500-1000 FEET HIGHER THAN THESE PROJECTIONS AT TIMES. LITTLE OR NO SNOW ACCUMULATION IS EXPECTED AROUND LAKE LEVEL IN THE TAHOE BASIN FOR THIS EVENT. MODEL QPF INDICATES UP TO 0.50 INCH OF LIQUID EQUIVALENT PRECIP NEAR THE SIERRA CREST WEST OF TAHOE, WHICH WOULD ROUGHLY TRANSLATE TO ABOUT 4 INCHES OF WET SNOW ABOVE 7000 FEET. A BROAD AREA OF RAINFALL BETWEEN 0.05 AND 0.20 INCH IS ALSO INDICATED DOWNSTREAM ACROSS MUCH OF WESTERN NEVADA. PRECIP CHANCES WERE INCREASED ACROSS THE HIGHWAY 50 AND I-80 CORRIDORS FOR LATE TONIGHT, BUT GIVEN THE LATEST MODEL TRENDS, RAIN CHANCES MAY NEED TO BE INCREASED SOONER IN THESE AREAS. FOR TUESDAY, SHOWERS ARE EXPECTED TO WIND DOWN AS FLAT RIDGE BUILDS OVER THE REGION. A WARMING TREND IS EXPECTED WITH DAYTIME TEMPS INCREASING TO THE LOWER 60S FOR MOST WESTERN NV VALLEYS. FOR WEDNESDAY AND WEDNESDAY NIGHT, FURTHER WARMING IS LIKELY AS WINDS INCREASE AHEAD OF NEXT TROUGH APPROACHING THE WEST COAST. THERE IS SOME UNCERTAINTY AGAIN WITH ONSET TIME OF RAIN AND HIGH ELEVATION SNOW AS THE ECMWF BRINGS SOME LIGHT PRECIP TO NORTHEAST CA DURING THE DAY, WHILE THE GFS HOLDS OFF ON MEASURABLE PRECIP UNTIL WEDNESDAY NIGHT. THE MAJORITY OF THE GUIDANCE IS INDICATING STRONGER PRECIP SHADOWING EAST OF THE SIERRA CREST, WHILE IN THE SIERRA THE SNOW LEVELS ARE LIKELY TO BE EVEN HIGHER THAN THE FIRST PRECIP EVENT FOR TODAY AND TONIGHT. THE MAIN IMPACT IN WESTERN NV IS MORE LIKELY TO BE A PERIOD OF GUSTY WINDS WEDNESDAY NIGHT AHEAD OF THE TROUGH PASSAGE. MJD LONG TERM...THURSDAY THROUGH SUNDAY... ONLY SIGNIFICANT CHANGES MADE TO THE EXTENDED FORECAST WERE TO BUMP UP POPS THURSDAY MORNING AND ADD POPS FOR SUNDAY. MEDIUM RANGE DETERMINISTIC MODELS AND GEFS ENSEMBLE MEMBERS ALL BRING A SHORT WAVE TROUGH THROUGH THE NRN PART OF THE REGION THURSDAY WITH A WEAK COLD FRONT PASSING THROUGH MOST OF THE CWA BEFORE STALLING AND FURTHER WEAKENING OVER THE SRN 1/3 OF THE REGION. WINDS SHOULD PICK UP AHEAD OF THIS SYSTEM...BUT STAY LESS THAN ADVISORY CRITERIA. WHILE QPF OVER FAR NRN AREAS IS BETTER THAN 0.50 INCHES...SNOW LEVELS WITH THIS SYSTEM START FAIRLY HIGH. THUS...ACCUMULATIONS SHOULD BE LIMITED TO THE HIGHER ELEVATIONS AND FOR NOW WE DO NOT SEE WINTER WEATHER ADVISORIES FOR THIS SYSTEM. OF COURSE...THIS COULD ALL CHANGE. SHORT WAVE RIDGE BUILDS FOR FRIDAY THEN SLIDES EAST SATURDAY AS ANOTHER TROUGH DIGS INTO THE ERN PACIFIC. AFTER WARM TEMPS ON THURSDAY THERE WILL BE A BRIEF COOL DOWN ON FRIDAY...THEN TEMPS BUMP UP AGAIN FOR SATURDAY. SATURDAY COULD BE ANOTHER ONE OF THOSE DAYS WHERE WINDS GUST INTO THE 40 MPH RANGE...ESPECIALLY FROM HWY 50 NORTHWARD. THE NEXT SHORT WAVE MOVES INTO THE COAST ON SUNDAY. THIS SYSTEM APPEARS TO HAVE A DECENT MOISTURE TAP AND SHOULD HAVE GOOD ENOUGH DYNAMICS TO SQUEEZE OUT PCPN OVER THE NRN 2/3RDS OF THE CWA. THE BEST PCPN CHANCES FOR NOW LOOK TO BE FROM THE TAHOE BASIN NORTHWARD INTO NE CA. EVEN SO...THIS FAR OUT PCPN AMOUNTS ARE QUITE VARIABLE WITH ECMWF SHOWING THE BEST AT AROUND 0.35 INCHES OVER THE NW CWA. ALL THIS IS SUBJECT TO CHANGE AS WE APPROACH THE EVENT NEXT WEEKEND SO RIGHT NOW THE CONFIDENCE IS ONLY MEDIUM IN MUCH DEVELOPING WITH THIS SYSTEM. 20 AVIATION... PRECIPITATION IS SPREADING INTO THE NRN CA COAST THIS MORNING. AS THE DAY PROGRESSES THIS PRECIPITATION SHOULD SPREAD OVER THE NRN FORECAST AREA. VFR CONDITIONS FOR THE AREA THIS MORNING WILL GIVE WAY TO MVFR CONDITIONS BY EARLY AFTERNOON NORTH OF THE TAHOE BASIN. IFR/MVFR CONDITIONS WILL DEVELOP FROM THE TAHOE BASIN NORTH ACROSS NE CA AND FAR NW NV BY EARLY EVENING WITH MOST MOUNTAINS OBSCURED. FARTHER SOUTH AND EAST VFR CONDITIONS WILL PERSIST LONGER. SNOW LEVELS START FAIRLY HIGH TODAY SO ANY TERMINALS THAT PICK UP PRECIPITATION THROUGH THE EARLY EVENING HOURS SHOULD SEE ALL RAIN. SNOW LEVELS WILL BRIEFLY DROP TO THE VALLEY FLOORS AROUND THE LAKE TAHOE BASIN AND PARTS OF PLUMAS AND LASSEN COUNTIES THIS EVENING IN HEAVIER PRECIPITATION BANDS. THIS WILL DRIVE KTRK AND KTVL TO IFR CONDITIONS FOR A BRIEF PERIOD OF TIME AFTER 4/02 UTC...BUT ANY ACCUMULATIONS ON THE RUNWAYS WILL BE MINIMAL. RIDGE GUSTS SHOULD BE NO WORSE THAN 50 MPH TODAY AND THIS EVENING. SHOWERS LINGER NEAR THE SIERRA CREST BY EARLY TUESDAY MORNING BUT MOST OTHER AREAS SEE A DECREASE IN CLOUDS AS A WEAK SHORT WAVE RIDGE BUILDS OVER THE AREA. ANOTHER TROUGH OF LOW PRESSURE BRINGS A RENEWED CHANCE FOR PRECIPITATION TO THE REGION BY WEDNESDAY/WEDNESDAY NIGHT. 20 && .REV WATCHES/WARNINGS/ADVISORIES... NV...NONE. CA...NONE. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS RENO NV
329 AM PST MON MAR 3 2014 .SYNOPSIS... A BAND OF SUBTROPICAL PACIFIC MOISTURE WILL BRING AREAS OF RAIN AND HIGH ELEVATION SNOW TO THE SIERRA AND WESTERN NEVADA LATER TODAY AND TONIGHT. MORE RAIN AND SNOW IS LIKELY IN THE SIERRA AND NORTHEAST CALIFORNIA BY WEDNESDAY NIGHT AS ANOTHER FAST MOVING LOW PRESSURE MOVES THROUGH. LATER THIS WEEK, DRY WEATHER WILL RETURN. ABOVE NORMAL TEMPERATURES ARE EXPECTED THROUGH THE UPCOMING WEEK. && .SHORT TERM... WATER VAPOR SATELLITE LOOP SHOWS A RATHER IMPRESSIVE BAND OF PACIFIC MOISTURE EXTENDING FROM HAWAII TO THE CENTRAL CA COAST. PRECIPITABLE WATER VALUES APPROACH 1.5 INCHES NEAR THE WEST COAST. HOWEVER, DESPITE THIS DECENT AMOUNT OF MOISTURE, FORCING IS LIMITED WHICH WILL LIMIT PRECIPITATION INTENSITY EAST OF THE SIERRA CREST AND INTO WESTERN NV THROUGH TONIGHT. WHILE THE 00Z MODEL GUIDANCE FAVORED THE BEST CHANCE FOR RAIN AND HIGH ELEVATION SNOW FOR LATER TONIGHT, THE 06Z GFS AND RECENT HRRR RUNS SPREAD MORE AREAS OF LIGHT PRECIP ACROSS THE REGION DURING THE DAY, WITH A GRADUAL SOUTHWARD PUSH TONIGHT. SNOW LEVELS ARE CURRENTLY PROJECTED TO RANGE FROM 6500 TO 7000 FEET, BUT GIVEN THE SUBTROPICAL AND EVEN TROPICAL ORIGIN OF THIS MOISTURE PLUME, THEY COULD RISE 500-1000 FEET HIGHER THAN THESE PROJECTIONS AT TIMES. LITTLE OR NO SNOW ACCUMULATION IS EXPECTED AROUND LAKE LEVEL IN THE TAHOE BASIN FOR THIS EVENT. MODEL QPF INDICATES UP TO 0.50 INCH OF LIQUID EQUIVALENT PRECIP NEAR THE SIERRA CREST WEST OF TAHOE, WHICH WOULD ROUGHLY TRANSLATE TO ABOUT 4 INCHES OF WET SNOW ABOVE 7000 FEET. A BROAD AREA OF RAINFALL BETWEEN 0.05 AND 0.20 INCH IS ALSO INDICATED DOWNSTREAM ACROSS MUCH OF WESTERN NEVADA. PRECIP CHANCES WERE INCREASED ACROSS THE HIGHWAY 50 AND I-80 CORRIDORS FOR LATE TONIGHT, BUT GIVEN THE LATEST MODEL TRENDS, RAIN CHANCES MAY NEED TO BE INCREASED SOONER IN THESE AREAS. FOR TUESDAY, SHOWERS ARE EXPECTED TO WIND DOWN AS FLAT RIDGE BUILDS OVER THE REGION. A WARMING TREND IS EXPECTED WITH DAYTIME TEMPS INCREASING TO THE LOWER 60S FOR MOST WESTERN NV VALLEYS. FOR WEDNESDAY AND WEDNESDAY NIGHT, FURTHER WARMING IS LIKELY AS WINDS INCREASE AHEAD OF NEXT TROUGH APPROACHING THE WEST COAST. THERE IS SOME UNCERTAINTY AGAIN WITH ONSET TIME OF RAIN AND HIGH ELEVATION SNOW AS THE ECMWF BRINGS SOME LIGHT PRECIP TO NORTHEAST CA DURING THE DAY, WHILE THE GFS HOLDS OFF ON MEASURABLE PRECIP UNTIL WEDNESDAY NIGHT. THE MAJORITY OF THE GUIDANCE IS INDICATING STRONGER PRECIP SHADOWING EAST OF THE SIERRA CREST, WHILE IN THE SIERRA THE SNOW LEVELS ARE LIKELY TO BE EVEN HIGHER THAN THE FIRST PRECIP EVENT FOR TODAY AND TONIGHT. THE MAIN IMPACT IN WESTERN NV IS MORE LIKELY TO BE A PERIOD OF GUSTY WINDS WEDNESDAY NIGHT AHEAD OF THE TROUGH PASSAGE. MJD .LONG TERM...THURSDAY THROUGH SUNDAY... ONLY SIGNIFICANT CHANGES MADE TO THE EXTENDED FORECAST WERE TO BUMP UP POPS THURSDAY MORNING AND ADD POPS FOR SUNDAY. MEDIUM RANGE DETERMINISTIC MODELS AND GEFS ENSEMBLE MEMBERS ALL BRING A SHORT WAVE TROUGH THROUGH THE NRN PART OF THE REGION THURSDAY WITH A WEAK COLD FRONT PASSING THROUGH MOST OF THE CWA BEFORE STALLING AND FURTHER WEAKENING OVER THE SRN 1/3 OF THE REGION. WINDS SHOULD PICK UP AHEAD OF THIS SYSTEM...BUT STAY LESS THAN ADVISORY CRITERIA. WHILE QPF OVER FAR NRN AREAS IS BETTER THAN 0.50 INCHES...SNOW LEVELS WITH THIS SYSTEM START FAIRLY HIGH. THUS...ACCUMULATIONS SHOULD BE LIMITED TO THE HIGHER ELEVATIONS AND FOR NOW WE DO NOT SEE WINTER WEATHER ADVISORIES FOR THIS SYSTEM. OF COURSE...THIS COULD ALL CHANGE. SHORT WAVE RIDGE BUILDS FOR FRIDAY THEN SLIDES EAST SATURDAY AS ANOTHER TROUGH DIGS INTO THE ERN PACIFIC. AFTER WARM TEMPS ON THURSDAY THERE WILL BE A BRIEF COOL DOWN ON FRIDAY...THEN TEMPS BUMP UP AGAIN FOR SATURDAY. SATURDAY COULD BE ANOTHER ONE OF THOSE DAYS WHERE WINDS GUST INTO THE 40 MPH RANGE...ESPECIALLY FROM HWY 50 NORTHWARD. THE NEXT SHORT WAVE MOVES INTO THE COAST ON SUNDAY. THIS SYSTEM APPEARS TO HAVE A DECENT MOISTURE TAP AND SHOULD HAVE GOOD ENOUGH DYNAMICS TO SQUEEZE OUT PCPN OVER THE NRN 2/3RDS OF THE CWA. THE BEST PCPN CHANCES FOR NOW LOOK TO BE FROM THE TAHOE BASIN NORTHWARD INTO NE CA. EVEN SO...THIS FAR OUT PCPN AMOUNTS ARE QUITE VARIABLE WITH ECMWF SHOWING THE BEST AT AROUND 0.35 INCHES OVER THE NW CWA. ALL THIS IS SUBJECT TO CHANGE AS WE APPROACH THE EVENT NEXT WEEKEND SO RIGHT NOW THE CONFIDENCE IS ONLY MEDIUM IN MUCH DEVELOPING WITH THIS SYSTEM. 20 && .AVIATION... PRECIPITATION IS SPREADING INTO THE NRN CA COAST THIS MORNING. AS THE DAY PROGRESSES THIS PRECIPITATION SHOULD SPREAD OVER THE NRN FORECAST AREA. VFR CONDITIONS FOR THE AREA THIS MORNING WILL GIVE WAY TO MVFR CONDITIONS BY EARLY AFTERNOON NORTH OF THE TAHOE BASIN. IFR/MVFR CONDITIONS WILL DEVELOP FROM THE TAHOE BASIN NORTH ACROSS NE CA AND FAR NW NV BY EARLY EVENING WITH MOST MOUNTAINS OBSCURED. FARTHER SOUTH AND EAST VFR CONDITIONS WILL PERSIST LONGER. SNOW LEVELS START FAIRLY HIGH TODAY SO ANY TERMINALS THAT PICK UP PRECIPITATION THROUGH THE EARLY EVENING HOURS SHOULD SEE ALL RAIN. SNOW LEVELS WILL BRIEFLY DROP TO THE VALLEY FLOORS AROUND THE LAKE TAHOE BASIN AND PARTS OF PLUMAS AND LASSEN COUNTIES THIS EVENING IN HEAVIER PRECIPITATION BANDS. THIS WILL DRIVE KTRK AND KTVL TO IFR CONDITIONS FOR A BRIEF PERIOD OF TIME AFTER 4/02 UTC...BUT ANY ACCUMULATIONS ON THE RUNWAYS WILL BE MINIMAL. RIDGE GUSTS SHOULD BE NO WORSE THAN 50 MPH TODAY AND THIS EVENING. SHOWERS LINGER NEAR THE SIERRA CREST BY EARLY TUESDAY MORNING BUT MOST OTHER AREAS SEE A DECREASE IN CLOUDS AS A WEAK SHORT WAVE RIDGE BUILDS OVER THE AREA. ANOTHER TROUGH OF LOW PRESSURE BRINGS A RENEWED CHANCE FOR PRECIPITATION TO THE REGION BY WEDNESDAY/WEDNESDAY NIGHT. 20 && .REV WATCHES/WARNINGS/ADVISORIES... NV...NONE. CA...NONE. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
647 AM EST MON MAR 3 2014 .SYNOPSIS... AN AREA OF LOW PRESSURE AND BACK DOOR COLD FRONT WILL MOVE THROUGH THIS AFTERNOON AND EVENING PROVIDING A CHANCE OF SHOWERS FOLLOWED BY MUCH COOLER TEMPERATURES. COOL HIGH PRESSURE WILL REMAIN ACROSS THE REGION TUESDAY THROUGH WEDNESDAY...WITH A SLIGHT CHANCE OF SHOWERS MAINLY ACROSS SOUTHERN AREAS POSSIBLE TUESDAY NIGHT AND WEDNESDAY. AN AREA OF LOW PRESSURE RIDING BY TO OUR SOUTH AND EAST WILL PROVIDE A BETTER CHANCE OF RAIN LATE WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...POSSIBLY LINGERING INTO FRIDAY. FAIR WEATHER EXPECTED SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... COLD FRONT TO OUR NORTH AND WEST WITH SURFACE HIGH PRESSURE RIDGE WELL TO OUR SE. SW LOW LEVEL FLOW AND UPPER LEVEL CLOUDINESS KEEPING OUR TEMPS WARM EARLY THIS MORNING. STRONG UPPER LEVEL DISTURBANCE...APPROACHING THE LOWER MISSISSIPPI VALLEY EARLY THIS MORNING...WILL MOVE EAST ACROSS THE CAROLINAS THIS AFTERNOON AND EVENING. SURFACE LOW PRESSURE WILL DEVELOP ALONG THE FRONT AND MOVE EAST ALONG IT. ASSOCIATED SHOWER ACTIVITY...CURRENTLY STRETCHING OVER THE SOUTHERN APPS/NW SC/N GA WILL SHIFT EAST INTO OUR NW FA BY 12Z TO 13Z...AND MOVE EAST ACROSS THE REMAINDER OF THE FA LATER THIS MORNING AND AFTERNOON. COLD FRONT WILL BACK DOOR THROUGH OUR FORECAST AREA (FA) FROM THE NORTH BEHIND THE DEPARTING SURFACE LOW THIS AFTERNOON AND EVENING. MAIN QUESTION INVOLVES PRECIP TYPE BEHIND THE FRONT. EXPECT A RAPID COOL DOWN WITH SHALLOW COLD AIR MOVING IN BEHIND THE FRONT ACCOMPANIED BY A WIND SHIFT WITH BREEZY NE WINDS. HOWEVER AT THE SAME TIME THE LOW LEVEL COLD AIR WILL BE MOVING IN...MODELS INDICATE MID AND UPPER LEVELS WILL BE DRYING OUT. SO...AT THIS TIME..IT APPEARS A BRIEF PERIOD OF LIGHT SLEET OR FREEZING DRIZZLE WILL BE POSSIBLE MAINLY FOR THE NE FA THIS EVENING AND EARLY TONIGHT. NO SIGNIFICANT ACCUMULATION EXPECTED. IMPACT EXPECTED TO BE MINIMAL...SO WILL NOT ISSUE AN ADVISORY. WIND GUSTS AROUND 25 KTS AT TIMES TODAY AND TONIGHT BOTH AHEAD OF AND BEHIND THE FRONT. WIND GUSTS ON WARMER AREA LAKES TONIGHT COULD APPROACH LAKE WIND ADVISORY CRITERIA...BUT CONFIDENCE A LITTLE TOO LOW TO ISSUE LWA AT THIS TIME. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... FRONT TO PUSH TO OUR SOUTH AND EAST WITH HIGH PRESSURE BUILDING INTO THE EASTERN SEABOARD. MODELS INDICATE A SERIES OF UPPER IMPULSES TO MOVE ACROSS THE REGION TUE/WED LEADING TO A SURFACE WAVE OR TWO RIDING ALONG THE STALLED FRONT AND POSSIBLY BRINGING SOME LIGHT PRECIPITATION INTO OUR REGION. GFS APPEARS TO BE AN OUTLIER WITH A STRONGER SURFACE LOW AND HIGHER POPS. WILL FAVOR SHORT RANGE ENSEMBLE GUIDANCE DUE TO MODEL DISCREPANCY...AND GIVEN APPEARANCE OF DRY MID LEVELS...THINK SLIGHT CHANCE POPS FAVORING THE SOUTHERN FA TUE NT AND WED LOOKS OK. LOOKING AT PARTIAL THICKNESS VALUES AND FORECAST SOUNDINGS...PRECIP TYPE EXPECTED TO BE ALL RAIN. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... STRONGER UPPER ENERGY MOVING INTO THE SE CONUS WILL PROMOTE A MORE SIGNIFICANT SURFACE LOW DEVELOPING ALONG THE OLD STALLED FRONT TO OUR SOUTH PROVIDING MOISTURE RETURN INTO OUR FA FOR WED NT THRU THU NT. STILL SOME DIFFERENCES NOTED BETWEEN GFS AND ECMWF WITH ECMWF STRONGER WITH THE UPPER LOW AND FARTHER NORTH WITH THE SURFACE LOW...THUS PROVIDING A WETTER SOLUTION FOR OUR FA. LARGE RANGE IN POPS NOTED IN GFS ENSEMBLE GUIDANCE. HPC GUIDANCE PROVIDING LIKELY POPS...IN LINE WITH ONGOING FORECAST. IN SITU WEDGE AT THE SURFACE. LATEST MODEL GUIDANCE TRENDING A LITTLE WARMER WITH LOW LEVEL TEMPS/THICKNESS VALUES AND SURFACE WET BULB TEMPS...AND IT STILL APPEARS ALL RAIN FOR THE PRECIP TYPE. ECMWF ALSO SLOWER WITH THE UPPER SYSTEM MOVING OUT WITH INDICATIONS OF LIGHT PRECIP POSSIBLY LINGERING THROUGH FRIDAY. HIGH PRESSURE TO BUILD IN FOR SATURDAY. GFS BRINGS THE NEXT FRONT IN SUNDAY...WHILE ECMWF APPEARS TO HOLD OFF UNTIL MAYBE SUN NT OR MON. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... A SOUTHWEST FLOW WILL OCCUR BETWEEN HIGH PRESSURE OFF THE SOUTHEAST COAST AND THE APPROACHING STRONG COLD FRONT. EXPECT FRONTAL PASSAGE DURING THE 19Z TO 22Z TIME FRAME. MOISTURE WILL BE ON THE INCREASE AHEAD OF THE FRONT THROUGH THE MORNING HOURS. THE NAM AND GFS MOS PLUS SREF GUIDANCE MAINTAIN VFR CONDITIONS THROUGH THE MORNING. HOWEVER...THE HRRR SHOWED AN IFR CEILING SPREADING INTO THE AREA FROM THE SOUTHWEST ASSOCIATED WITH SOME LOW LEVEL ISENTROPIC LIFT. OBS THIS MORNING DO SHOW AN AREA OF LOW CLOUDS ACROSS SOUTHERN/EASTERN GA...BUT LOOKS LIKE THE STRATUS WILL MISS MOST OF THE TAF SITES EXCEPT POSSIBLY OGB WHERE I HAVE A TEMPO GROUP FOR LOWER CEILINGS THIS MORNING. LEANED TOWARD THE MAV AND MET MOS AND MAINTAINED VFR CONDITIONS BUT CONFIDENCE IS NOT HIGH BECAUSE OF THE INCONSISTENT HRRR GUIDANCE. STRONG MIXING HELPED PREVENT ANY FOG FORMATION THIS MORNING AND NON IS EXPECTED. THE LATEST KCAE 88D VAD WIND PROFILE INDICATED SIGNIFICANT LOW-LEVEL WIND SHEAR THIS MORNING. VWP CURRENTLY SHOWS A STRONG SOUTH SOUTHWEST 40 TO 45 KT JET FROM 1K FT AND ABOVE. THE NAM INDICATED SIGNIFICANT WIND SHEAR SHOULD CONTINUE UNTIL 14-15Z WHEN HEATING AND MIXING SHOULD BECOME MORE DOMINATE. LATER IN THE DAY...THE NAM AND GFS MOS DIFFERED WITH THE NAM SHOWING IFR CEILINGS DEVELOPING JUST BEHIND THE FRONT. THE GFS MOS INDICATED LOW-END VFR OR MVFR CEILINGS. WE AVERAGED THIS GUIDANCE AND FORECASTED MVFR CEILINGS. THE NAM MOS MAY BE TOO LOW WITH ITS CEILING FORECAST BECAUSE CONSIDERABLE WIND SHOULD HELP HOLD UP CEILINGS. THERE MAY ALSO BE RESTRICTIONS ASSOCIATED WITH RAIN NEAR AND BEHIND THE FRONT BUT BELIEVE THIS RAIN WILL BE MAINLY LIGHT WITH LIMITED EFFECT ON VISIBILITY. WINDS WILL BE ESPECIALLY GUSTY AHEAD OF THE FRONT DURING THE DAY MONDAY. THE GFS LAMP INDICATED GUSTS OF 15 TO 20 KNOTS. THE NAM MOMENTUM TRANSFER TOOL SUPPORTED GUSTS NEAR 25 KNOTS. THE NAM AND GFS MOS...EVEN WITH LOSS OF DAYTIME HEATING...STRONG CAA AND TIGHT PRESSURE GRADIENT WILL PRODUCE BREEZY CONDITIONS THIS EVENING BEHIND THE ARCTIC FRONT WITH NORTH NORTHEAST WINDS AROUND 15 KTS WITH GUSTS AROUND 20 KTS. AFTER MIDNIGHT...WINDS WILL DIMINISH SOMEWHAT BUT REMAIN NORTH NORTHEAST AROUND 10 KTS WITH HIGHER GUSTS THROUGH DAYBREAK. EXTENDED AVIATION OUTLOOK...LOW PRESSURE TRACKING NORTHEASTWARD ALONG THE SOUTHEAST COAST MAY RESULT IN WIDESPREAD MVFR OR IFR CONDITIONS WEDNESDAY NIGHT THROUGH FRIDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
745 AM EST MON MAR 3 2014 .UPDATE... ISSUED AT 745 AM EST MON MAR 3 2014 WENT AHEAD AND UPDATED THE TEXT PRODUCTS TO REMOVE THE FLOOD WATCH IN THE SOUTH AND ALSO DROP THE HEAVY SNOW AND THUNDER MENTION. ALSO FINE TUNED TEMPERATURES AND DEWPOINTS THROUGH THE NEXT FEW HOURS FOR OBS AND TRENDS. THESE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. IN ADDITION...THE ZONES AND HWO WERE UPDATED. UPDATE ISSUED AT 615 AM EST MON MAR 3 2014 THE BACK EDGE OF THE HEAVIER PCPN IS NOW MOVING THROUGH THE SOUTHERN PART OF THE CWA. WHEN THIS EXITS WE WILL LOSE MUCH OF THE CONVECTIVE PCPN AND THREAT OF THUNDER. LIGHTER SNOWS WILL CONTINUE OFF AND ON FOR MUCH OF THE DAY UNTIL THE DEFORMATION ZONES PASSES THROUGH EAST KENTUCKY LATER THIS AFTERNOON. HAVE UPDATED THE GRIDS TO REFLECT THE LATEST RADAR TRENDS AND GUIDANCE FROM THE HRRR AND 06Z NAM12. ALSO FINE TUNED THE T AND TD GRIDS FOR THE NEXT SEVERAL HOURS PER THE LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. A MORE COMPLETE UPDATE TO THE TEXT PRODUCTS WILL TAKE PLACE WITH THE EXPIRATION OF THE FLOOD WATCH AT 7 AM. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 315 AM EST MON MAR 3 2014 ...THE REST OF THE NIGHT THROUGH TODAY... ...MAJOR WINTER STORM CONTINUES THROUGH THE MORNING... 07Z SFC ANALYSIS...AND RADAR/SATELLITE IMAGERY...SHOWS A WELL DEFINED LOW PRESSURE AREA ROLLING EAST NORTHEAST THROUGH THE TENNESSEE VALLEY. THIS IS RUNNING ALONG AN ARCTIC BOUNDARY THAT CONTINUES TO SAG SOUTH THROUGH THE THIN REMAINDER OF THE STATE NOT IN THE DEEP FREEZE. THE WARM NOSE WITH THIS SYSTEM REMAINS AN ISSUE FOR MUCH OF THE AREA ALONG AND SOUTH OF THE MOUNTAIN PARKWAY...PER OBS AND THE TRANSITION SHOWING UP IN THE DOPPLER CC LOOP. A PERIOD OF FREEZING RAIN HAS BEEN DEPOSITING GENERALLY BETWEEN A TENTH TO A QUARTER OF AN INCH OF ICE BEFORE THE SLEET STARTS TO REALLY ACCUMULATE FOR MOST PLACES. REPORTS OF HALF INCH SLEET TOTALS ARE STARTING TO COME IN FROM PLACES NORTH AND WEST OF JKL. THE OFFICE IS PUSHING THAT TOTAL...AS WELL...THOUGH SOME SNOW HAS BEEN MIXING IN AT TIMES. THE STRENGTH OF THE ARCTIC AIR MASS...AND THE BAROCLINIC ZONE IT HAS LAID ACROSS EAST KENTUCKY...IS EVIDENCED BY THE MID TEENS CURRENTLY IN NORTHERN FLEMING COUNTY...LOW 20S ALONG THE WESTERN HALF OF THE MOUNTAIN PARKWAY...AND MID 30S BARELY HOLDING ON OVER THE FAR SOUTHEAST. NORTHEAST WINDS CONTINUE TO PUSH THE COLD AIR DEEPER INTO THE CWA WITH EVEN SOME GUSTS TO 15 OR 20 KTS SHOWING UP IN THE OBS CLOSER TO THE BLUEGRASS. THIS WILL ADD TO THE CONCERN FOR POWER OUTAGES AND TREE DAMAGE. ON RADAR...AN EXTENDED MASS OF PCPN REMAINS TO TRANSITION THROUGH EAST KENTUCKY WHERE IT WILL BE CONVERTED TO MAINLY SLEET AND SNOW...THOUGH FOR A TIME HEAVY RAIN AND FREEZING RAIN WILL BE POSSIBLE ACROSS THE FAR SOUTHEAST. NO CG RETURNS HAVE SHOWN UP WITH THE NORTHERN PORTION OF THIS SYSTEM IN AWHILE...BUT WOULD NOT RULE OUT SOME IN CLOUD OR CLOUD TO CLOUD BOLTS ACROSS THE AREA FOR THE NEXT SEVERAL HOURS. THE MODELS ARE IN GOOD AGREEMENT WITH THE MID LEVELS AND THE SHORTWAVE RESPONSIBLE FOR THE SFC SYSTEM GIVING US A LION OF A START TO MARCH. THIS WAVE IS CURRENTLY TRAVERSING NORTHERN ARKANSAS AND WILL ROLL NEARLY DUE EAST INTO THE SOUTHERN APPALACHIANS BY EVENING. THE MODEL AGREEMENT ALOFT DOES NOT TRANSLATE TO AGREEMENT AT THE SFC FOR A COMPLEX ONGOING SYSTEM SUCH AS THIS. SO...HAVE INSTEAD LEANED ON THE LATEST GUIDANCE FROM THE HRRR AND THE NAM12 COMBINED WITH TRENDS AND PCPN PROGRESSION TO GUIDE THE NEAR TERM FORECAST. THE HEAVY PCPN...GRADUALLY GOING TO SNOW AND FALLING AT OVER AN INCH AN HOUR...WILL MOVE THROUGH THE AREA EARLY THIS MORNING WITH A BACK EDGE AND A TAPER REACHING FAR WESTERN PARTS OF THE CWA BY 7 AM AND SWEEPING EAST BY 10 AM. HAVE USED THIS FOR TIMING THE WORST OF THE WEATHER. WILL CONTINUE THE MENTION OF THUNDER INTO THE PRE DAWN HOURS FOR THIS HEAVY PCPN BAND. THE SNOW TOTALS WILL BE LIMITED BY THE SLEET...THOUGH...SO IN A SENSE WE ARE DODGING A BULLET...BUT THE ROADS WILL TAKE THE BRUNT OF THIS STORM...AS A RESULT. THE HRRR ALSO SHOWS THE LAST OF THE DEFORMATION ZONE...BASICALLY WHAT IS GOING ON NEAR THE UPPER LOW IN SOUTHWEST MISSOURI CURRENTLY...PASSING THROUGH DURING THE EARLY AFTERNOON HOURS WITH AN ADDITIONAL INCH OR TWO OF SNOW POSSIBLE BEFORE IT TAPERS OFF AN ENDS FROM WEST TO EAST. HAVE DRAWN UP THE GRIDS WITH THESE TWO PCPN AREAS AND THEIR PROGRESS IN MIND. ACCORDINGLY...WILL HOLD ON TO THE WARNINGS AS THEY ARE WITH SOME CLEAN UP POSSIBLE TOWARD 12Z. WILL ALSO KEEP THE FLOOD WATCH AS HEAVY PCPN IN A SEMI-LIQUID FORM IS STILL EXPECTED FOR MUCH OF THAT AREA. EXPECT A GENERAL 3 TO 5 INCH SNOW AND SLEET ACCUMULATION THROUGH THE NORTHERN PART OF THE CWA WITH SLIGHTLY LESSER AMOUNTS SOUTH...BUT JUST AS MUCH SLEET...1/2 TO 1 INCH...THROUGHOUT THE ENTIRE AREA. THIS WILL BE DELINEATED FURTHER IN THE FORTHCOMING WSW UPDATES. USED THE CONSSHORT FOR TEMPERATURES...DEWPOINTS...AND WINDS...BC VERSION FOR THE LATTER TWO...THROUGH 00Z TUESDAY. ALSO DERIVED THE MAX AND MIN TEMPS FROM THE HOURLY TEMP GRIDS. AS FOR POPS...ENDED UP JUST ON THE HIGH SIDE OF ALL GUIDANCE WITH THE TAPER OF THE SNOW DURING THE DAYLIGHT HOURS TODAY. ...TONIGHT THROUGH TUESDAY... ONCE THIS SYSTEM MOVES TO THE SE OF THE REGION THIS EVENING...A STRONG MASS OF HIGH PRESSURE WILL TAKE HOLD ACROSS THE OHIO RIVER VALLEY...WITH UPPER LEVEL RIDGING FINALLY TAKING SHAPE ACROSS MUCH OF THE CONUS. THIS SET UP SHOULD KEEP KY DRY FOR THE NEXT 24 HOURS...AS WELL AS USHER IN DRY CANADIAN AIR INTO THE REGION. WITH THE PASSAGE OF THE COLD FRONT...AND THIS PUSH OF COLDER...DRIER CANADIAN AIR...EXPECT LOWS TO DROP DOWN WELL BELOW NORMAL ONCE MORE TONIGHT. OVERNIGHT LOWS ARE ONLY EXPECTED TO BE IN THE SINGLE DIGITS ABOVE ZERO ACROSS THE NORTHERN CWA...TO THE LOW TEENS IN THE SOUTHERN COUNTIES. WITH THE FRONTAL SYSTEM THAT JUST PASSED THROUGH...WINDS WERE GUSTY IN MANY LOCATIONS. LUCKILY...EXPECT THESE WINDS TO DIE DOWN BY TONIGHT. THIS WILL HAVE GOOD AND BAD IMPLICATIONS. ON THE DOWN SIDE...LIGHTER WINDS...IN ADDITION TO CLEAR SKIES AND A COOLER AIR MASS OVERHEAD...WILL PROVIDE OPTIMAL RADIATIONAL COOLING...HENCE THE EXPECTED OVERNIGHT LOW TEMPS. ON THE UP SIDE...WITH TEMPERATURES EXPECTED TO DROP THIS LOW...ANY AMOUNT OF WIND WILL ONLY AID TO THE WIND CHILL FACTOR...MAKING CONDITIONS FEEL EVEN COLDER THAN THEY REALLY ARE. THAT BEING SAID...WINDS WILL NOT BE NIL. WE CAN EXPECT LIGHT WINDS IN THE 3 TO 7 KT RANGE...WHICH WILL STILL BE ENOUGH TO DROP WIND CHILL READINGS DOWN INTO THE SINGLE DIGITS BELOW ZERO ACROSS THE NORTH. COLD AIR WILL CONTINUE TO FILTER IN DURING THE DAY TUESDAY...BUT HIGHER SUN ANGLES FOR MARCH...AND AN ABUNDANT AMOUNT OF SUNSHINE WITH THIS DRY AIR MASS IN PLACE...THIS WILL HELP TEMPERATURES TO BOUNCE BACK TO JUST ABOVE FREEZING IN THE NORTH...AND POSSIBLY INTO THE LOW 40S ACROSS THE FAR SOUTHEAST COUNTIES. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 421 AM EST MON MAR 3 2014 A SURFACE HIGH PRESSURE RIDGE OVER THE REGION WILL BE BREAKING DOWN AT THE START OF THE PERIOD...BUT DRY AIR WILL STILL BE IN PLACE AND THEIR WILL BE NO SIGNIFICANT UPPER LEVEL FEATURES THROUGH AT LEAST WEDNESDAY...SO THE WEATHER WILL REMAIN UNEVENTFUL. ON WEDNESDAY NIGHT...AN AMPLIFYING TROUGH WILL BE DROPPING SE TOWARD THE LOWER MISSISSIPPI VALLEY. MODELS ARE NOW LESS INCLINED TO CLOSE OFF A MID/UPPER LEVEL LOW WITH THIS SYSTEM...AND AS A RESULT THEY ARE MORE PROGRESSIVE WITH IT. SURFACE DEVELOPMENT IS STILL INDICATED OVER THE GULF...BUT IT TRACKS FURTHER EAST THAN IN RUNS OF RECENT DAYS. AS A RESULT...IT IS LOOKING LESS LIKELY THAT WE WILL SEE DIRECT EFFECTS FROM THE CYCLOGENESIS. HOWEVER...THE MID/UPPER LEVEL TROUGH COULD BRING SOME LIGHT RAIN ON THURSDAY OR THURSDAY EVENING AS IT PASSES. A TRANSITORY RIDGE AT THE SURFACE AND ALOFT WILL THEN MOVE THROUGH ON FRIDAY AND FRIDAY NIGHT...WITHOUT ANY COOLING IN THE WAKE OF THE DEPARTING SYSTEM. ANOTHER LARGE SCALE MID/UPPER LEVEL TROUGH AND ITS ASSOCIATED COLD FRONT ARE EXPECTED TO HEAD IN FROM THE NW DURING THE WEEKEND. GFS AND ECMWF AGREE ON THE BIG PICTURE FOR THIS...BUT SHOW SOME TIMING DIFFERENCES. TAKING BOTH INTO CONSIDERATION...THE MOST LIKELY TIME FOR PRECIP WILL BE SATURDAY NIGHT. WITH THE UNCERTAINTY...HAVE KEPT POPS IN THE CHANCE CATEGORY EVEN FOR SATURDAY NIGHT...WITH A BUFFER OF LOWER POPS ON BOTH SIDES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 625 AM EST MON MAR 3 2014 LIFR AND IFR CONDITIONS WILL BE THE RULE THIS MORNING ACROSS THE AREA AS LIGHT TO MODERATE SNOW MOVES THROUGH EAST KENTUCKY. FAR SOUTHEAST PARTS OF THE STATE ARE STILL EXPERIENCING SOME SLEET AND FREEZING RAIN. CONDITIONS WILL BEGIN TO IMPROVE FROM WEST TO EAST TOWARDS MID MORNING...BUT ANOTHER ROUND OF MAINLY LIGHT SNOW WILL MOVE IN DURING THE EARLY AFTERNOON AND CONTINUE CONDITIONS IN THE MVFR AND IFR RANGE FOR A BUT LONGER. VFR WX SHOULD TAKE OVER THE REGION LATER THIS AFTERNOON AND LAST INTO THE NIGHT. WINDS WILL BE NORTHEAST AROUND 10 KTS WITH GUSTS TO 20 KTS POSSIBLE THROUGH MIDDAY...BEFORE SETTLING TO LESS THAN 10 KTS AND BECOME MORE EASTERLY LATER THIS AFTERNOON AND INTO THE NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR KYZ044- 050>052. WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR KYZ058>060-068-069-104-106>109-111-112-114. WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR KYZ079-080- 083>088-110-113-115>120. && $$ UPDATE...GREIF SHORT TERM...GREIF/JMW LONG TERM...HAL AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
625 AM EST MON MAR 3 2014 .UPDATE... ISSUED AT 615 AM EST MON MAR 3 2014 THE BACK EDGE OF THE HEAVIER PCPN IS NOW MOVING THROUGH THE SOUTHERN PART OF THE CWA. WHEN THIS EXITS WE WILL LOSE MUCH OF THE CONVECTIVE PCPN AND THREAT OF THUNDER. LIGHTER SNOWS WILL CONTINUE OFF AND ON FOR MUCH OF THE DAY UNTIL THE DEFORMATION ZONES PASSES THROUGH EAST KENTUCKY LATER THIS AFTERNOON. HAVE UPDATED THE GRIDS TO REFLECT THE LATEST RADAR TRENDS AND GUIDANCE FROM THE HRRR AND 06Z NAM12. ALSO FINE TUNED THE T AND TD GRIDS FOR THE NEXT SEVERAL HOURS PER THE LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. A MORE COMPLETE UPDATE TO THE TEXT PRODUCTS WILL TAKE PLACE WITH THE EXPIRATION OF THE FLOOD WATCH AT 7 AM. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 315 AM EST MON MAR 3 2014 ...THE REST OF THE NIGHT THROUGH TODAY... ...MAJOR WINTER STORM CONTINUES THROUGH THE MORNING... 07Z SFC ANALYSIS...AND RADAR/SATELLITE IMAGERY...SHOWS A WELL DEFINED LOW PRESSURE AREA ROLLING EAST NORTHEAST THROUGH THE TENNESSEE VALLEY. THIS IS RUNNING ALONG AN ARCTIC BOUNDARY THAT CONTINUES TO SAG SOUTH THROUGH THE THIN REMAINDER OF THE STATE NOT IN THE DEEP FREEZE. THE WARM NOSE WITH THIS SYSTEM REMAINS AN ISSUE FOR MUCH OF THE AREA ALONG AND SOUTH OF THE MOUNTAIN PARKWAY...PER OBS AND THE TRANSITION SHOWING UP IN THE DOPPLER CC LOOP. A PERIOD OF FREEZING RAIN HAS BEEN DEPOSITING GENERALLY BETWEEN A TENTH TO A QUARTER OF AN INCH OF ICE BEFORE THE SLEET STARTS TO REALLY ACCUMULATE FOR MOST PLACES. REPORTS OF HALF INCH SLEET TOTALS ARE STARTING TO COME IN FROM PLACES NORTH AND WEST OF JKL. THE OFFICE IS PUSHING THAT TOTAL...AS WELL...THOUGH SOME SNOW HAS BEEN MIXING IN AT TIMES. THE STRENGTH OF THE ARCTIC AIR MASS...AND THE BAROCLINIC ZONE IT HAS LAID ACROSS EAST KENTUCKY...IS EVIDENCED BY THE MID TEENS CURRENTLY IN NORTHERN FLEMING COUNTY...LOW 20S ALONG THE WESTERN HALF OF THE MOUNTAIN PARKWAY...AND MID 30S BARELY HOLDING ON OVER THE FAR SOUTHEAST. NORTHEAST WINDS CONTINUE TO PUSH THE COLD AIR DEEPER INTO THE CWA WITH EVEN SOME GUSTS TO 15 OR 20 KTS SHOWING UP IN THE OBS CLOSER TO THE BLUEGRASS. THIS WILL ADD TO THE CONCERN FOR POWER OUTAGES AND TREE DAMAGE. ON RADAR...AN EXTENDED MASS OF PCPN REMAINS TO TRANSITION THROUGH EAST KENTUCKY WHERE IT WILL BE CONVERTED TO MAINLY SLEET AND SNOW...THOUGH FOR A TIME HEAVY RAIN AND FREEZING RAIN WILL BE POSSIBLE ACROSS THE FAR SOUTHEAST. NO CG RETURNS HAVE SHOWN UP WITH THE NORTHERN PORTION OF THIS SYSTEM IN AWHILE...BUT WOULD NOT RULE OUT SOME IN CLOUD OR CLOUD TO CLOUD BOLTS ACROSS THE AREA FOR THE NEXT SEVERAL HOURS. THE MODELS ARE IN GOOD AGREEMENT WITH THE MID LEVELS AND THE SHORTWAVE RESPONSIBLE FOR THE SFC SYSTEM GIVING US A LION OF A START TO MARCH. THIS WAVE IS CURRENTLY TRAVERSING NORTHERN ARKANSAS AND WILL ROLL NEARLY DUE EAST INTO THE SOUTHERN APPALACHIANS BY EVENING. THE MODEL AGREEMENT ALOFT DOES NOT TRANSLATE TO AGREEMENT AT THE SFC FOR A COMPLEX ONGOING SYSTEM SUCH AS THIS. SO...HAVE INSTEAD LEANED ON THE LATEST GUIDANCE FROM THE HRRR AND THE NAM12 COMBINED WITH TRENDS AND PCPN PROGRESSION TO GUIDE THE NEAR TERM FORECAST. THE HEAVY PCPN...GRADUALLY GOING TO SNOW AND FALLING AT OVER AN INCH AN HOUR...WILL MOVE THROUGH THE AREA EARLY THIS MORNING WITH A BACK EDGE AND A TAPER REACHING FAR WESTERN PARTS OF THE CWA BY 7 AM AND SWEEPING EAST BY 10 AM. HAVE USED THIS FOR TIMING THE WORST OF THE WEATHER. WILL CONTINUE THE MENTION OF THUNDER INTO THE PRE DAWN HOURS FOR THIS HEAVY PCPN BAND. THE SNOW TOTALS WILL BE LIMITED BY THE SLEET...THOUGH...SO IN A SENSE WE ARE DODGING A BULLET...BUT THE ROADS WILL TAKE THE BRUNT OF THIS STORM...AS A RESULT. THE HRRR ALSO SHOWS THE LAST OF THE DEFORMATION ZONE...BASICALLY WHAT IS GOING ON NEAR THE UPPER LOW IN SOUTHWEST MISSOURI CURRENTLY...PASSING THROUGH DURING THE EARLY AFTERNOON HOURS WITH AN ADDITIONAL INCH OR TWO OF SNOW POSSIBLE BEFORE IT TAPERS OFF AN ENDS FROM WEST TO EAST. HAVE DRAWN UP THE GRIDS WITH THESE TWO PCPN AREAS AND THEIR PROGRESS IN MIND. ACCORDINGLY...WILL HOLD ON TO THE WARNINGS AS THEY ARE WITH SOME CLEAN UP POSSIBLE TOWARD 12Z. WILL ALSO KEEP THE FLOOD WATCH AS HEAVY PCPN IN A SEMI-LIQUID FORM IS STILL EXPECTED FOR MUCH OF THAT AREA. EXPECT A GENERAL 3 TO 5 INCH SNOW AND SLEET ACCUMULATION THROUGH THE NORTHERN PART OF THE CWA WITH SLIGHTLY LESSER AMOUNTS SOUTH...BUT JUST AS MUCH SLEET...1/2 TO 1 INCH...THROUGHOUT THE ENTIRE AREA. THIS WILL BE DELINEATED FURTHER IN THE FORTHCOMING WSW UPDATES. USED THE CONSSHORT FOR TEMPERATURES...DEWPOINTS...AND WINDS...BC VERSION FOR THE LATTER TWO...THROUGH 00Z TUESDAY. ALSO DERIVED THE MAX AND MIN TEMPS FROM THE HOURLY TEMP GRIDS. AS FOR POPS...ENDED UP JUST ON THE HIGH SIDE OF ALL GUIDANCE WITH THE TAPER OF THE SNOW DURING THE DAYLIGHT HOURS TODAY. ...TONIGHT THROUGH TUESDAY... ONCE THIS SYSTEM MOVES TO THE SE OF THE REGION THIS EVENING...A STRONG MASS OF HIGH PRESSURE WILL TAKE HOLD ACROSS THE OHIO RIVER VALLEY...WITH UPPER LEVEL RIDGING FINALLY TAKING SHAPE ACROSS MUCH OF THE CONUS. THIS SET UP SHOULD KEEP KY DRY FOR THE NEXT 24 HOURS...AS WELL AS USHER IN DRY CANADIAN AIR INTO THE REGION. WITH THE PASSAGE OF THE COLD FRONT...AND THIS PUSH OF COLDER...DRIER CANADIAN AIR...EXPECT LOWS TO DROP DOWN WELL BELOW NORMAL ONCE MORE TONIGHT. OVERNIGHT LOWS ARE ONLY EXPECTED TO BE IN THE SINGLE DIGITS ABOVE ZERO ACROSS THE NORTHERN CWA...TO THE LOW TEENS IN THE SOUTHERN COUNTIES. WITH THE FRONTAL SYSTEM THAT JUST PASSED THROUGH...WINDS WERE GUSTY IN MANY LOCATIONS. LUCKILY...EXPECT THESE WINDS TO DIE DOWN BY TONIGHT. THIS WILL HAVE GOOD AND BAD IMPLICATIONS. ON THE DOWN SIDE...LIGHTER WINDS...IN ADDITION TO CLEAR SKIES AND A COOLER AIR MASS OVERHEAD...WILL PROVIDE OPTIMAL RADIATIONAL COOLING...HENCE THE EXPECTED OVERNIGHT LOW TEMPS. ON THE UP SIDE...WITH TEMPERATURES EXPECTED TO DROP THIS LOW...ANY AMOUNT OF WIND WILL ONLY AID TO THE WIND CHILL FACTOR...MAKING CONDITIONS FEEL EVEN COLDER THAN THEY REALLY ARE. THAT BEING SAID...WINDS WILL NOT BE NIL. WE CAN EXPECT LIGHT WINDS IN THE 3 TO 7 KT RANGE...WHICH WILL STILL BE ENOUGH TO DROP WIND CHILL READINGS DOWN INTO THE SINGLE DIGITS BELOW ZERO ACROSS THE NORTH. COLD AIR WILL CONTINUE TO FILTER IN DURING THE DAY TUESDAY...BUT HIGHER SUN ANGLES FOR MARCH...AND AN ABUNDANT AMOUNT OF SUNSHINE WITH THIS DRY AIR MASS IN PLACE...THIS WILL HELP TEMPERATURES TO BOUNCE BACK TO JUST ABOVE FREEZING IN THE NORTH...AND POSSIBLY INTO THE LOW 40S ACROSS THE FAR SOUTHEAST COUNTIES. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 421 AM EST MON MAR 3 2014 A SURFACE HIGH PRESSURE RIDGE OVER THE REGION WILL BE BREAKING DOWN AT THE START OF THE PERIOD...BUT DRY AIR WILL STILL BE IN PLACE AND THEIR WILL BE NO SIGNIFICANT UPPER LEVEL FEATURES THROUGH AT LEAST WEDNESDAY...SO THE WEATHER WILL REMAIN UNEVENTFUL. ON WEDNESDAY NIGHT...AN AMPLIFYING TROUGH WILL BE DROPPING SE TOWARD THE LOWER MISSISSIPPI VALLEY. MODELS ARE NOW LESS INCLINED TO CLOSE OFF A MID/UPPER LEVEL LOW WITH THIS SYSTEM...AND AS A RESULT THEY ARE MORE PROGRESSIVE WITH IT. SURFACE DEVELOPMENT IS STILL INDICATED OVER THE GULF...BUT IT TRACKS FURTHER EAST THAN IN RUNS OF RECENT DAYS. AS A RESULT...IT IS LOOKING LESS LIKELY THAT WE WILL SEE DIRECT EFFECTS FROM THE CYCLOGENESIS. HOWEVER...THE MID/UPPER LEVEL TROUGH COULD BRING SOME LIGHT RAIN ON THURSDAY OR THURSDAY EVENING AS IT PASSES. A TRANSITORY RIDGE AT THE SURFACE AND ALOFT WILL THEN MOVE THROUGH ON FRIDAY AND FRIDAY NIGHT...WITHOUT ANY COOLING IN THE WAKE OF THE DEPARTING SYSTEM. ANOTHER LARGE SCALE MID/UPPER LEVEL TROUGH AND ITS ASSOCIATED COLD FRONT ARE EXPECTED TO HEAD IN FROM THE NW DURING THE WEEKEND. GFS AND ECMWF AGREE ON THE BIG PICTURE FOR THIS...BUT SHOW SOME TIMING DIFFERENCES. TAKING BOTH INTO CONSIDERATION...THE MOST LIKELY TIME FOR PRECIP WILL BE SATURDAY NIGHT. WITH THE UNCERTAINTY...HAVE KEPT POPS IN THE CHANCE CATEGORY EVEN FOR SATURDAY NIGHT...WITH A BUFFER OF LOWER POPS ON BOTH SIDES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 625 AM EST MON MAR 3 2014 LIFR AND IFR CONDITIONS WILL BE THE RULE THIS MORNING ACROSS THE AREA AS LIGHT TO MODERATE SNOW MOVES THROUGH EAST KENTUCKY. FAR SOUTHEAST PARTS OF THE STATE ARE STILL EXPERIENCING SOME SLEET AND FREEZING RAIN. CONDITIONS WILL BEGIN TO IMPROVE FROM WEST TO EAST TOWARDS MID MORNING...BUT ANOTHER ROUND OF MAINLY LIGHT SNOW WILL MOVE IN DURING THE EARLY AFTERNOON AND CONTINUE CONDITIONS IN THE MVFR AND IFR RANGE FOR A BUT LONGER. VFR WX SHOULD TAKE OVER THE REGION LATER THIS AFTERNOON AND LAST INTO THE NIGHT. WINDS WILL BE NORTHEAST AROUND 10 KTS WITH GUSTS TO 20 KTS POSSIBLE THROUGH MIDDAY...BEFORE SETTLING TO LESS THAN 10 KTS AND BECOME MORE EASTERLY LATER THIS AFTERNOON AND INTO THE NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR KYZ044- 050>052. WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR KYZ058>060-068-069-104-106>109-111-112-114. FLOOD WATCH UNTIL 7 AM EST THIS MORNING FOR KYZ068-069-079-080- 083>088-107-109-110-112>120. WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR KYZ079-080- 083>088-110-113-115>120. && $$ UPDATE...GREIF SHORT TERM...GREIF/JMW LONG TERM...HAL AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
627 AM EST MON MAR 3 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 514 AM EST MON MAR 3 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEP MID/UPPER LEVEL LOW CENTERED OVER NRN QUEBEC. WITH TROF EXTENDING W INTO WRN CANADA... ARCTIC AIR CONTINUES TO COVER A VAST AREA OF CANADA INTO THE NRN CONUS. HOWEVER...THE COLD IS MODERATING AS 00Z RAOBS SHOWED 850MB TEMPS OF -21C/-17C/-21C AT KINL/KGRB/KAPX RESPECTIVELY...ALL SEVERAL DEGREES HIGHER THAN 24 HRS AGO. COLD WILL CONTINUE TO MODERATE OVER THE COMING DAYS AS PACIFIC AIR BEGINS TO SPREAD E IN LOW AMPLITUDE FLOW. SFC TROF THAT PUSHED ACROSS THE AREA LAST NIGHT BROUGHT A WIND SHIFT TO THE NW ACROSS LAKE SUPERIOR. A LONE LAKE EFFECT CLOUD/-SHSN BAND EMANATING FROM A PATCH OF OPEN WATER/BKN ICE NEAR ISLE ROYALE WAS EXTENDING SSE AND COMBINING WITH ADDITIONAL MOISTURE FROM SOME OPEN WATER/BKN ICE TO THE LEE OF THE KEWEENAW TO BRING FLURRIES/-SHSN TO PORTIONS OF EASTERN MARQUETTE/WRN ALGER COUNTY EARLY THIS MORNING. OTHERWISE...CLEAR SKIES/MOSTLY CALM WINDS AND A VERY DRY COLUMN HAVE ALLOWED TEMPS TO PLUMMET TO -10 TO -25F IN GENERAL. TODAY WILL BE A QUIET DAY WITH SUNSHINE GIVING WAY TO INCREASING HIGH CLOUDS FROM THE W IN ADVANCE OF SHORTWAVE CURRENTLY MOVING ACROSS THE NRN ROCKIES. MODERATING ARCTIC AIR MASS AND SUNSHINE WORKING ON LOWER ALBEDO FORESTED TERRAIN WILL HELP TEMPS RISE INTO THE TEENS IN MOST AREAS. TEMPS MAY STILL FAIL TO GET ABOVE 10F OVER THE KEWEENAW AND THE NE FCST AREA AS WINDS OFF THE FROZEN LAKE LIMIT MIXING DEPTH. NAM/GEM SHOW A LAKE BREEZE OR MAYBE MORE APPROPRIATE...ICE BREEZE...DEVELOPING INTO THE MARQUETTE AREA THIS AFTN. IF SO...TEMPS MAY FALL BACK SEVERAL DEGREES AFTER RISING INTO THE TEENS. ALTHOUGH TIMING IS NOT WELL AGREED UPON YET...MODELS ARE IN GOOD AGREEMENT THAT AN AREA OF -SN WILL SPREAD ACROSS UPPER MI AT SOME POINT TONIGHT AS AFOREMENTIONED SHORTWAVE MOVES ACROSS THE UPPER MISSISSIPPI VALLEY AND WRN GREAT LAKES. FCST AREA WILL BE ON THE NRN PORTION OF ISENTROPIC ASCENT/DEEP LAYER FORCING AS WELL AS UPPER DIVERGENCE ASSOCIATED WITH JET STREAK EXTENDING EASTWARD FROM NRN LAKE SUPERIOR/ONTARIO. THUS...POPS WILL BE HIGHEST ACROSS THE S (LIKELY) WITH CHC TO THE N. WITH MIXING RATIOS AROUND 1G/KG AVBL PER 280K SFC (ROUGHLY 700-725MB) AND 6HRS OR SO OF -SN...EXPECT SNOW ACCUMULATIONS OF LESS THAN 1 INCH N TO PERHAPS 1-2INCHES FAR SCNTRL...CLOSER TO STRONGER FORCING. WITH THICKENING CLOUDS...TEMPS AT MANY LOCATIONS WILL PROBABLY NOT FALL BLO 0F TONIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 507 AM EST MON MAR 3 2014 A WEAK SHORTWAVE WILL BE OVER THE SERN CWA 12Z TUE...WITH THE BULK OF ANY LIGHT SNOW SE OF THE CWA AFTER 12Z TUE. HAVE SOME SLIGHT CHANCE POPS LINGERING BEHIND THE SYSTEM INTO TUE...BUT ONLY VERY MINOR SNOWFALL AMOUNTS ARE EXPECTED. HIGH PRESSURE TO THE NE OF THE CWA WILL KEEP THE FORECAST DRY ON WED...WITH AT LEAST CHANCES OF PRECIP RETURNING THU INTO FRI AS MODEL INDICATE THAT A SHORTWAVE MAY MOVE INTO THE REGION. THERE IS SIGNIFICANT MODEL DISAGREEMENT AND RUN TO RUN DISCONTINUITY WITH THE SHORTWAVE...SO USED A CONSENSUS OF GUIDANCE WHICH GAVE SLIGHT CHANCE TO LOW CHANCE POPS THU INTO FRI. SHOULD SEE WARMING TEMPS /BUT STILL BELOW NORMAL/ AHEAD OF THE SHORTWAVE THU AND FRI AS RETURN FLOW SETS UP ACROSS THE REGION...WITH HIGHS IN THE MID 20S TO NEAR 30 ON FRI. A COLDER AIRMASS AND DRY HIGH PRESSURE DOMINATE NEXT WEEKEND...WITH HIGHS IN THE LOW TO MID 20S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 626 AM EST MON MAR 3 2014 WITH VERY DRY LOW LEVEL AIR ACROSS THE REGION AND NEAR COMPLETE ICE COVER ON LAKE SUPERIOR...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO THE EARLY EVENING. HIGH AND MID CLOUDS WILL GRADUALLY INCREASE THIS AFTN/EVENING AHEAD OF THE NEXT DISTURBANCE. -SN WILL THEN OVERSPREAD THE AREA TONIGHT...BRINGING MVFR CONDITIONS. WITH KCMX ON THE NRN FRINGE OF THE SYSTEM...IT`S POSSIBLE CONDITIONS MAY REMAIN VFR TONIGHT. NOT OUT OF THE QUESTION THAT VIS COULD DROP TO IFR FOR A TIME AT KIWD/KSAW. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 514 AM EST MON MAR 3 2014 TIGHTENING PRES GRADIENT WILL RESULT WESTERLY WINDS INCREASING TO 15-25KT ACROSS MUCH OF LAKE SUPERIOR TODAY. SFC TROF THEN MOVES ACROSS THE AREA LATER TONIGHT/TUE...BRINGING A WEAKER PRES GRADIENT. AS A RESULT...WINDS WILL FALL BACK UNDER 20KT TONIGHT THRU TUE. WINDS WILL REMAIN UNDER 20KT THRU WED. SOUTHERLY WINDS WILL THEN BE ON THE INCREASE THU AHEAD OF A LOW PRES TROF APPROACHING FROM THE W. TROF WILL CROSS THE UPPER LAKES FRI...BRINGING A WIND SHIFT TO THE NW. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
515 AM EST MON MAR 3 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 514 AM EST MON MAR 3 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEP MID/UPPER LEVEL LOW CENTERED OVER NRN QUEBEC. WITH TROF EXTENDING W INTO WRN CANADA... ARCTIC AIR CONTINUES TO COVER A VAST AREA OF CANADA INTO THE NRN CONUS. HOWEVER...THE COLD IS MODERATING AS 00Z RAOBS SHOWED 850MB TEMPS OF -21C/-17C/-21C AT KINL/KGRB/KAPX RESPECTIVELY...ALL SEVERAL DEGREES HIGHER THAN 24 HRS AGO. COLD WILL CONTINUE TO MODERATE OVER THE COMING DAYS AS PACIFIC AIR BEGINS TO SPREAD E IN LOW AMPLITUDE FLOW. SFC TROF THAT PUSHED ACROSS THE AREA LAST NIGHT BROUGHT A WIND SHIFT TO THE NW ACROSS LAKE SUPERIOR. A LONE LAKE EFFECT CLOUD/-SHSN BAND EMANATING FROM A PATCH OF OPEN WATER/BKN ICE NEAR ISLE ROYALE WAS EXTENDING SSE AND COMBINING WITH ADDITIONAL MOISTURE FROM SOME OPEN WATER/BKN ICE TO THE LEE OF THE KEWEENAW TO BRING FLURRIES/-SHSN TO PORTIONS OF EASTERN MARQUETTE/WRN ALGER COUNTY EARLY THIS MORNING. OTHERWISE...CLEAR SKIES/MOSTLY CALM WINDS AND A VERY DRY COLUMN HAVE ALLOWED TEMPS TO PLUMMET TO -10 TO -25F IN GENERAL. TODAY WILL BE A QUIET DAY WITH SUNSHINE GIVING WAY TO INCREASING HIGH CLOUDS FROM THE W IN ADVANCE OF SHORTWAVE CURRENTLY MOVING ACROSS THE NRN ROCKIES. MODERATING ARCTIC AIR MASS AND SUNSHINE WORKING ON LOWER ALBEDO FORESTED TERRAIN WILL HELP TEMPS RISE INTO THE TEENS IN MOST AREAS. TEMPS MAY STILL FAIL TO GET ABOVE 10F OVER THE KEWEENAW AND THE NE FCST AREA AS WINDS OFF THE FROZEN LAKE LIMIT MIXING DEPTH. NAM/GEM SHOW A LAKE BREEZE OR MAYBE MORE APPROPRIATE...ICE BREEZE...DEVELOPING INTO THE MARQUETTE AREA THIS AFTN. IF SO...TEMPS MAY FALL BACK SEVERAL DEGREES AFTER RISING INTO THE TEENS. ALTHOUGH TIMING IS NOT WELL AGREED UPON YET...MODELS ARE IN GOOD AGREEMENT THAT AN AREA OF -SN WILL SPREAD ACROSS UPPER MI AT SOME POINT TONIGHT AS AFOREMENTIONED SHORTWAVE MOVES ACROSS THE UPPER MISSISSIPPI VALLEY AND WRN GREAT LAKES. FCST AREA WILL BE ON THE NRN PORTION OF ISENTROPIC ASCENT/DEEP LAYER FORCING AS WELL AS UPPER DIVERGENCE ASSOCIATED WITH JET STREAK EXTENDING EASTWARD FROM NRN LAKE SUPERIOR/ONTARIO. THUS...POPS WILL BE HIGHEST ACROSS THE S (LIKELY) WITH CHC TO THE N. WITH MIXING RATIOS AROUND 1G/KG AVBL PER 280K SFC (ROUGHLY 700-725MB) AND 6HRS OR SO OF -SN...EXPECT SNOW ACCUMULATIONS OF LESS THAN 1 INCH N TO PERHAPS 1-2INCHES FAR SCNTRL...CLOSER TO STRONGER FORCING. WITH THICKENING CLOUDS...TEMPS AT MANY LOCATIONS WILL PROBABLY NOT FALL BLO 0F TONIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 507 AM EST MON MAR 3 2014 A WEAK SHORTWAVE WILL BE OVER THE SERN CWA 12Z TUE...WITH THE BULK OF ANY LIGHT SNOW SE OF THE CWA AFTER 12Z TUE. HAVE SOME SLIGHT CHANCE POPS LINGERING BEHIND THE SYSTEM INTO TUE...BUT ONLY VERY MINOR SNOWFALL AMOUNTS ARE EXPECTED. HIGH PRESSURE TO THE NE OF THE CWA WILL KEEP THE FORECAST DRY ON WED...WITH AT LEAST CHANCES OF PRECIP RETURNING THU INTO FRI AS MODEL INDICATE THAT A SHORTWAVE MAY MOVE INTO THE REGION. THERE IS SIGNIFICANT MODEL DISAGREEMENT AND RUN TO RUN DISCONTINUITY WITH THE SHORTWAVE...SO USED A CONSENSUS OF GUIDANCE WHICH GAVE SLIGHT CHANCE TO LOW CHANCE POPS THU INTO FRI. SHOULD SEE WARMING TEMPS /BUT STILL BELOW NORMAL/ AHEAD OF THE SHORTWAVE THU AND FRI AS RETURN FLOW SETS UP ACROSS THE REGION...WITH HIGHS IN THE MID 20S TO NEAR 30 ON FRI. A COLDER AIRMASS AND DRY HIGH PRESSURE DOMINATE NEXT WEEKEND...WITH HIGHS IN THE LOW TO MID 20S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1210 AM EST MON MAR 3 2014 WITH VERY DRY LOW LEVEL AIR ACROSS THE REGION AND NEAR COMPLETE ICE COVER ON LAKE SUPERIOR...VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH MOST OF THE FCST PERIOD. MID CLOUDS WILL GRADUALLY INCREASE LATE TODAY INTO THE EVENING AHEAD OF THE NEXT DISTURBANCE. MVFR VSBY/CIG WILL BE MORE LIKELY AT IWD WITH THE ARRIVAL OF SOME LIGHT SNOW THAN SITES FARTHER TO THE EAST WHERE CONDITIONS MAY LOWER AFT 04/06Z. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 514 AM EST MON MAR 3 2014 TIGHTENING PRES GRADIENT WILL RESULT WESTERLY WINDS INCREASING TO 15-25KT ACROSS MUCH OF LAKE SUPERIOR TODAY. SFC TROF THEN MOVES ACROSS THE AREA LATER TONIGHT/TUE...BRINGING A WEAKER PRES GRADIENT. AS A RESULT...WINDS WILL FALL BACK UNDER 20KT TONIGHT THRU TUE. WINDS WILL REMAIN UNDER 20KT THRU WED. SOUTHERLY WINDS WILL THEN BE ON THE INCREASE THU AHEAD OF A LOW PRES TROF APPROACHING FROM THE W. TROF WILL CROSS THE UPPER LAKES FRI...BRINGING A WIND SHIFT TO THE NW. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...JLB MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
524 AM MST MON MAR 3 2014 .UPDATE... A BRIEF PERIOD OF FREEZING RAIN OCCURRED IN BILLINGS JUST BEFORE 5 AM MST...AND LIVINGSTON HAS ALSO REPORTED BRIEF FREEZING RAIN...SO AT LEAST VERY LIGHT PRECIPITATION IS OCCURRING WITH ECHOES SEEN ON RADAR IMAGERY. WE UPDATED THE FORECAST TO INCREASE POPS FURTHER TO THE 4O AND 50 PERCENT RANGE THIS MORNING FROM HARDIN SOUTHEASTWARD TO THE BROADUS AND EKALAKA AREAS. WE ALSO EXPANDED THE AREA WITH A MENTION OF FREEZING RAIN TO ALMOST EVERYWHERE EXCEPT THE BAKER AND EKALAKA AREAS. IT/S APPARENT BASED ON THE BRIEF FREEZING RAIN THAT OCCURRED AT BILLINGS WHERE ALMOST ALL GUIDANCE /INCLUDING THE MOST RECENT RAP CYCLE/ SUGGESTS 850-HPA TEMPERATURES BELOW 0 C THAT THE MODELS ARE COMPLETELY UNDERDOING THE AMOUNT OF WARMING ALOFT. THUS IT IS NOT CLEAR HOW FAR ACROSS SOUTHEASTERN MT THE ABOVE-FREEZING LAYER ABOVE THE SURFACE EXISTS. WE HELD OFF ON ISSUING A FREEZING RAIN ADVISORY FOR NOW BECAUSE IT APPEARS THE MOISTURE IS VERY LIGHT...WHICH MAY NOT MAKE ROADS MUCH WORSE THAN THEY ARE ALREADY IN MOST AREAS. THE THREAT IS ONE WHICH WE ARE DEFINITELY CARRYING IN OUR MESSAGING THOUGH. && .SHORT TERM...VALID FOR TDY AND TUE... THE NEXT 36 HOURS WILL BE AN ESPECIALLY CHALLENGING PERIOD AS COLD ARCTIC AIR RETREATS...OFFERING UP POTENTIAL FOR RAPID WARMING WHEN AND WHERE THE SHALLOW INVERSION MIXES OUT...BUT POTENTIAL FOR HUGE TEMPERATURE BUSTS WHERE IT DOES NOT DO SO AS READILY. TODAY...THE KBLX WSR-88D VAD WIND PROFILE SUGGESTS THE COLD AIR IS IS VERY SHALLOW /LESS THAN 2000 FT DEEP/ AS OF 10 UTC AS THE WINDS NEAR THAT LEVEL ARE SOUTHWEST AT 25 KT. OBSERVATIONS IN AND AROUND THE HIGHER TERRAIN CONFIRM THIS IDEA WITH MANY LOCATIONS ABOVE THE 5000 FT LEVEL ABOVE 32 F EARLY THIS MORNING. EVEN A SPOTTER AT NYE REPORTED 40 F AND RAPIDLY COMPACTING/MELTING SNOW AT 08 UTC. THERE IS NO DOUBT THAT THIS WARM AIR MASS WILL WORK NORTH AND EAST TODAY WITH THE PASSAGE OF A WEAK 500-HPA SHORT WAVE TROUGH WHICH HAS ITS AXIS OVER WESTERN MT AT 10 UTC PER SATELLITE IMAGERY. THE GUIDANCE FROM 00 UTC REMAINS CONSISTENT IN PUSHING THE MID-LEVEL WARM FRONT WITH +4 TO +7 C 850-HPA TEMPERATURES NORTHEAST TO AT LEAST ROUNDUP AND HYSHAM OVER TOWARD BROADUS BY AFTERNOON. DEEP SNOW PACK IS ONE ISSUE WITH RESULTING SURFACE TEMPERATURES SINCE IT COULD COOL DOWN THE NEAR-SURFACE LAYER...BUT LINGERING INVERSIONS AND ANY DRAINAGE OF COLD AIR TRAPPED IN BASINS OR RIVER VALLEYS /SUCH AS THE CLARKS FORK INTO BILLINGS/ WILL LIKELY POSE A GREATER ISSUE. IT CERTAINLY GOES WITHOUT SAYING THAT WE WILL HAVE A WARM-UP TODAY...BUT WE ARE NOT CONFIDENT AT ALL IN FORECAST HIGHS IN MOST PLACES. WE CHOSE TO BLEND THE ONGOING FORECAST TOWARD THE 00 UTC GEM...AND WENT WARMER THAN EVEN THAT OUTPUT IN THE FOOTHILLS LIKE RED LODGE WERE WE HAVE HIGH CONFIDENCE IN HIGHS WELL INTO THE 40S F. WE CHOSE TO KEEP THE FORECAST HIGHS NEAR 32 F AT BILLINGS GIVEN A HIGH LIKELIHOOD FOR A CLARKS FORK DRAINAGE...BUT A 10 F BUST EITHER SIDE OF THAT IS VERY POSSIBLE. THE 06 UTC GFS PUSHES A WEST WIND INTO BILLINGS AFTER 00 UTC...SO IT/S EVEN POSSIBLE TEMPERATURES WILL RISE HIGHER INTO THE 30S F AFTER SUNSET IN BILLINGS. OTHERWISE...QUICK-HITTING FORCING WITH THE 500-HPA SHORT WAVE THIS MORNING COULD YIELD SOME PRECIPITATION...ESPECIALLY EAST OF A LINE FROM ROUNDUP TO BILLINGS AND LODGE GRASS FROM 12 TO 18 UTC. WE DID INCLUDE A MENTION OF FREEZING RAIN WITH SNOW THIS MORNING FOR MUCH OF SOUTH CENTRAL AND SOUTHEASTERN MT...BUT POPS ARE ONLY AROUND 30 PERCENT BASED ON UPSTREAM TRENDS. TONIGHT...ANOTHER...SLIGHTLY STRONGER 500-HPA SHORT WAVE IS SET TO CROSS THE AREA...POSING A GREATER RISK OF FREEZING RAIN OVER SOUTH CENTRAL AND SOUTHEASTERN MT. THE 03 UTC SREF CONFIRMS THE TOP-DOWN METHOD APPLIED TO FORECAST SOUNDINGS FROM THE DETERMINISTIC MODELS AS IT HAS HIGH /50 TO 90/ PERCENT PROBABILITIES OF LIQUID MOISTURE FROM ROUNDUP AND BILLINGS OVER TO FORSYTH AND BROADUS TONIGHT. ANY LIQUID MOISTURE WILL REFREEZE ON CONTACT REGARDLESS OF WHETHER THE AIR TEMPERATURES ARE ABOVE 32 F...SO AGAIN FREEZING RAIN IS NEEDED IN THE GRIDDED FORECAST. HOWEVER...THE FREEZING RAIN RISK IS GOING TO BE VERY CONDITIONAL ON PRECIPITATON ACTUALLY FORMING...WHICH IS NOT A SURE THING...AS BORNE OUT BY 03 UTC SREF PROBABILITIES FOR A HUNDREDTH OR MORE OF MOISTURE /WHICH ARE 50 PERCENT OR LOWER/. THE 00 UTC ECMWF ALSO BACKED OFF A BIT ON ITS QPF OVERNIGHT...SO THERE ARE SOME UNCERTAIN SIGNALS AND WE THEREFORE KEPT POPS IN THE 30 TO 40 PERCENT RANGE AND WENT WITHOUT ANY HEADLINES FOR NOW. THIS WILL LIKELY BE A CASE WHERE NEAR-TERM TRENDS AND HIGH-RESOLUTION MODELS WILL BE NEEDED TO HONE IN ON WHERE HIGHER PROBABILITIES OF IMPACTS WILL EXIST...IF THEY DO INDEED OCCUR. NOTE THAT THE MOUNTAINS WILL BE IN LINE FOR ANOTHER MORE-DEFINED SHOT OF SNOW TONIGHT AS WELL. TUE...WE HAVE HIGHER CONFIDENCE IN MORE WIDESPREAD 40+ F HIGHS FOR MUCH OF THE AREA BECAUSE THE 00 UTC GUIDANCE TURNS LOW-LEVEL WINDS TO THE WEST OR NORTHWEST BEHIND TONIGHT/S SHORT WAVE. IT DOES LOOK LIKE THE LOW- AND MID-LEVEL THERMAL GRADIENT MAY REMAIN HUNG UP IN SOUTHEASTERN MT AND MOS-BASED GUIDANCE LENDS SUPPORT TO LOW CLOUDS OR EVEN FOG IN PLACES LIKE BAKER AND MILES CITY...SO THERE IS ONCE MORE POTENTIAL FOR A LARGE TEMPERATURE GRADIENT TO BE IN PLAY OVER THE REGION. LOW POPS REMAIN IN THE FORECAST THROUGH TUE NIGHT WITH UNCERTAINTY IN SHORT WAVES IN A QUASI-ZONAL FLOW...BUT TAKING MOST OF THE 00 UTC GUIDANCE AT FACE VALUE SUGGESTS THIS COULD MAINLY BE A DRY PERIOD IN THE LOWER ELEVATIONS. SCHULTZ .LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN... MODELS CONSISTENT IN ADVERTISING AN UNSETTLED WEATHER PATTERN OVER THE REGION FOR WEDNESDAY THROUGH FRIDAY. UNSTABLE NORTHWEST FLOW WILL BE OVER THE NORTHERN PLAINS WITH PACIFIC MOISTURE MOVING ACROSS WITH NORTHERN STREAM ENERGY. PRECIPITATION ACROSS THE PLAINS WILL BE SCATTERED AS THIS ENERGY WILL MOVE THROUGH QUICKLY LIMITING ANY SIGNIFICANT ACCUMULATIONS. DID INCREASE POPS TO LIKELY OVER THE SOUTHWEST MOUNTAINS AS STRONGER JET DYNAMICS/ISENTROPIC AND OROGRAPHIC LIFT COMBINE TO BRING ACCUMULATING SNOWFALL TO MAINLY THE WEST FACING SLOPES. SNOW ACCUMULATIONS WILL BE IN THE 6 TO 8 INCH RANGE FOR WEDNESDAY THROUGH FRIDAY. FLOW BECOMING ZONAL WEDNESDAY NIGHT AND THURSDAY WITH 700 MB WINDS INCREASING TO 60 KTS. ENERGY MOVING ACROSS THE AREA WILL DEEPEN THE LEE SIDE TROUGH AND THIS WILL BRING A PERIOD OF GUSTY WINDS TO LIVINGSTON AND NEAR NYE. UPPER RIDGE OF HIGH PRESSURE BUILDING OVER THE AREA BY NEXT WEEKEND WHICH WILL BRING DRY WEATHER AND WARMING TEMPERATURES. TEMPERATURES WILL BE MODERATING THROUGH THE WEEK AND ABOVE SEASONAL VALUES CAN BE EXPECTED BY THE WEEKEND WITH READINGS IN THE LOW TO MID 50S. RICHMOND && .AVIATION... WARM MOIST AIR FLOWING OVER COLD SURFACE AIRMASS WILL KEEP OVERCAST CONDITIONS ACROSS THE REGION TODAY. AN UPPER LEVEL DISTURBANCE WILL PRODUCE PRECIPITATION AND LOWERED CEILINGS. VFR CONDITIONS WILL PREVAIL...EXCEPT FOR AREAS OF MVFR TO IFR WITH THE PRECIPITATION. PRECIPITATION TODAY WILL BE SNOW BUT THERE IS A SLIGHT CHANCE OF FREEZING RAIN FROM BILLINGS EAST TO FORSYTH THIS MORNING. ANOTHER DISTURBANCE WILL MOVE THROUGH OVERNIGHT AND WILL BRING AREAS OF LIGHT SNOW WITH LOCALIZED MVFR TO IFR CONDITIONS. A SHALLOW LAYER OF ARCTIC AIR WILL REMAIN OVER THE AREA TONIGHT AND THERE WILL BE A CHANCE OF FREEZING RAIN FROM BILLINGS TO MILES CITY. RICHMOND && .PRELIMINARY POINT TEMP/POPS... TDY TUE WED THU FRI SAT SUN ------------------------------------------------------- BIL 032 025/043 028/042 029/043 026/039 025/047 032/051 2/S 32/S 22/W 24/W 32/W 11/B 11/B LVM 043 028/045 028/043 031/047 027/042 025/046 029/051 3/O 33/S 32/W 35/W 32/W 21/B 12/W HDN 032 021/042 025/041 027/042 025/038 023/049 030/052 5/S 42/S 22/W 23/W 22/W 11/B 01/B MLS 019 011/028 019/036 022/037 018/030 016/043 030/047 4/S 43/S 22/W 33/W 22/J 11/B 11/B 4BQ 034 017/037 020/039 025/042 022/034 020/046 031/053 5/S 32/S 22/W 22/W 32/J 11/B 01/B BHK 020 007/023 015/034 020/033 015/029 013/039 027/045 4/S 33/S 22/W 23/W 32/J 11/B 01/B SHR 043 024/042 023/045 027/048 025/042 022/050 029/055 4/S 22/S 21/B 22/W 43/W 11/B 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1021 AM EST MON MAR 3 2014 .SYNOPSIS... AN ARCTIC COLD FRONT WILL MOVE SOUTH THROUGH THE AREA TODAY. COLD HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST TUESDAY AND WEDNESDAY AS WEAK LOW PRESSURE MOVES JUST OFF OF THE COAST. A DEVELOPING LOW PRESSURE SYSTEM WILL MOVE ALONG THE SOUTHEAST COAST THURSDAY AND FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 10 AM MON...MID MORNING UPDATE WAS MAINLY TO REFLECT CURRENT CONDITIONS. ADJUSTED POPS WITH THE LATEST HRRR AND WRF MODELS. MODELS ARE INDICATING PRECIP STARTING OUR WESTERN PART OF THE CWA APPROX 16Z...SO THEREFORE DECREASED POPS ALONG HWY 64 AND EAST OF HWY 17 TO SLIGHTLY CHANCE. LATEST SURFACE ANALYSIS HAS THE ARTIC COLD FRONT STRETCHING ACROSS GOLDSBORO TO CEDAR ISLAND. COLD FRONT WILL CONTINUE TO PUSH SOUTH ACROSS THE AREA THE MORNING INTO THE EARLY AFTERNOON WITH THE AREA OF LOW PRES PUSHING OFF CAPE FEAR THIS AFTERNOON AS A DAMPENING SHORTWAVE MOVES EWD ACROSS THE SOUTHEAST. MODELS IN FAIR AGREEMENT WITH THE FRONT NEAR THE ALBEMARLE SOUND AROUND 09Z...ALONG THE HIGHWAY 70 CORRIDOR AROUND 15Z AND PUSHING SOUTH OF THE AREA SHORTLY AFTER 18Z. PRECIP WILL DEVELOP BEHIND THE FRONTAL PASSAGE WITH OVERRUNNING MOISTURE AHEAD OF THE SHORTWAVE. BEST UPPER LEVEL DYNAMICS MOVE ACROSS THE AREA BETWEEN 18Z MON-00Z TUE AND EXPECT MOST OF THE PRECIP TO FALL DURING THIS TIME...EXCEPT PERHAPS ALONG THE IMMEDIATE COAST WHICH COULD CONTINUE INTO THE EARLY EVENING. INITIALLY PRECIP WILL FALL AS RAIN...BUT STRONG CAA ADVECTION WILL USHER IN A MUCH COLDER AIRMASS THROUGH THE DAY ALLOWING A WINTRY MIX TO DEVELOP FROM N TO S THROUGH THE AFTERNOON. WITH A 3-6C WARM NOSE PERSISTING THROUGH THE AFTERNOON...EXPECT THE RAIN TO TRANSITION TO MAINLY SLEET ALONG WITH WITH LIGHT FREEZING RAIN AS THE SFC COLD POOL WILL QUICKLY DEEPEN TO AROUND 3FT. MODEL/WPC AVERAGE STORM TOTAL LIQUID QPF IS AROUND A QUARTER TO A THIRD OF AN INCH. THERE WILL BE LIMITED TIME FROM WHEN THE THERMAL PROFILES FAVOR SLEET TO WHEN RAPID DRYING COMMENCES IN THE DENDRITIC GROWTH ZONE LATE IN THE AFTERNOON BRINGING A TRANSITION TO LIGHT FREEZING RAIN OR FREEZING DRIZZLE. THEREFORE...SLEET AND ICE ACCUMULATIONS ARE EXPECTED TO BE MINIMAL...GENERALLY ONE TO TWO TENTHS OF AN INCH OF SLEET AND TRACE TO PERHAPS A TENTH OF AN INCH OF ICE. THERMAL PROFILES FOR AREAS FROM AROUND RODANTHE SOUTH ALONG THE OUTER BANKS SUGGEST MAINLY RAIN FOR THESE AREAS...THOUGH COULD SEE SOME LIGHT SLEET LATE. HAVE MADE MINIMAL CHANGES TO THE FORECAST AND WILL MAINTAIN THE WINTER WEATHER ADVISORY FOR LIGHT SLEET AND ICE. STRONG CAA WILL BRING GUSTY NLY WINDS ACROSS THE REGION AFTER FROPA AND COULD SEE SUSTAINED WINDS APPROACH WIND ADVISORY LEVELS ACROSS THE OUTER BANKS AND PARTS OF DOWN EAST CARTERET COUNTY AND WILL ISSUE A WIND ADVISORY FROM MID AFTERNOON THROUGH MIDNIGHT WITH THE MORNING FORECAST PACKAGE. THESE WINDS WILL ALSO BRING MINOR WATER LEVEL RISES ALONG THE SOUTHERN PORTION OF THE PAMLICO SOUND BUT WITH THE SHORT DURATION ONLY AROUND 6-9 HRS NOT ANTICIPATING MUCH MORE THAN 1 TO 1.5 FT ABOVE NORMAL...WHICH IS WHAT IS INDICATED ON THE CERA WEBSITE. TEMPS WILL FOLLOW A NON-DIURNAL TREND WITH RAPID COOLING BEHIND THE FRONT. TEMPS CURRENTLY AROUND 48-58 ACROSS THE REGION EARLY THIS MORNING BUT EXPECT TEMPS TO QUICKLY FALL THROUGH THE 40S AND INTO THE 30S AFTER FROPA. THERE WILL LIKELY BE A LARGE SPREAD IN HIGHS TODAY WITH SOUTHERN SECTIONS LIKELY WARMING TO AROUND 60 THIS MORNING AHEAD OF THE FRONT WHILE NORTHERN SECTIONS WILL REACH THEIR HIGHS AROUND 50 AROUND DAYBREAK. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/... AS OF 330 AM MON...THE SHORTWAVE TROUGH QUICKLY PUSHES EAST OF THE AREA EARLY IN THE EVENING WITH UPPER LEVEL DYNAMICS QUICKLY DIMINISHING AND MID LEVEL DRYING ENDING BEST PRECIP PROCESSES. THERMAL PROFILES SUGGEST LIGHT FREEZING RAIN OR FREEZING DRIZZLE CONTINUING THROUGH THE EVENING HOURS MOST AREAS BUT ANY ADDITIONAL ACCUMULATION WILL BE VERY LIGHT. TEMPS WILL CONTINUE TO FALL INTO THE 20S MOST AREAS...EXCEPT 30-35 ALONG THE COAST...WITH BLACK ICE POSSIBLE ON UNTREATED ROADS CONTINUING TO BRING HAZARDOUS DRIVING CONDITIONS THROUGH THE OVERNIGHT. && .LONG TERM /TUESDAY THROUGH SUNDAY/... AS OF 255 AM MONDAY...FORECAST MODELS CONTINUE TO SHOW AN ACTIVE PATTERN ACROSS EASTERN NORTH CAROLINA FOR MOST OF THIS WEEK. ANY PRECIPITATION ON TUESDAY SHOULD BE NEAR THE COAST AS WAVE OF LOW PRESSURE MOVES WELL OFFSHORE AND HAVE KEPT LOW CHANCE POPS THRU THE DAY. COLD HIGH PRESSURE WILL WEDGE DOWN THE EASTERN SLOPES OF THE APPALACHIANS FROM THE NORTHEAST TUESDAY AFTERNOON AND WILL REMAIN LOCKED IN PLACE THROUGH LATE WEEK. THIS WILL KEEP TEMPERATURES BELOW SEASONAL NORMALS...BY SEVERAL DEGREES...AND KEEP SKIES RATHER CLOUDY FOR MOST OF THE WEEK. ANOTHER OFFSHORE WAVE OF LOW PRESSURE APPROACHES BY EARLY WEDNESDAY. WITH TEMPERATURES CLOSE TO FREEZING ACROSS THE FAR NORTHWESTERN CWA EARLY WEDNESDAY MORNING...HAVE KEPT A SMALL RISK OF SOME LIGHT FREEZING RAIN AS THE PRECIPITATION ARRIVES. THE PRECIPITATION SHOULD BECOME ALL RAIN AND CONTINUE INTO WEDNESDAY AFTERNOON BEFORE MOVING OFFSHORE. ANOTHER STRONGER WAVE OF LOW PRESSURE APPROACHES THURSDAY INTO FRIDAY. THE ECMWF IS NOT QUITE AS STRONG AS PREVIOUS RUNS...BUT BOTH THE ECMWF AND GFS SHOW A HIGH COVERAGE OF RAIN THURSDAY AND THURSDAY NIGHT. THERMAL PROFILES SUPPORT ALL RAIN WITH THIS SYSTEM...WITH LIKELY GUSTY WINDS AND THE POSSIBILITY OF MINOR COASTAL FLOODING ISSUES. A RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE SOUTH WITH A WARMER SOUTHWEST FLOW FOR SATURDAY. A FAST-MOVING COLD FRONT MAY LEAD TO ANOTHER QUICK SHOT OF RAIN ON SUNDAY. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... SHORT TERM /THROUGH SUNDAY EVENING/... AS OF 730 AM MON...VFR CONDITIONS WILL PREVAIL EARLY THIS MORNING WITH LIGHT S/SW FLOW. A BACKDOOR COLD FRONT ALONG THE HIGHWAY 264 CORRIDOR WILL CONTINUE TO PUSH SOUTH ACROSS RTES THIS MORNING INTO EARLY AFTERNOON WITH STRONG CAA IN NLY FLOW. CIGS LOWER TO MVFR WITH -RA DEVELOPING AT THE TERMINALS BETWEEN 14-17Z...THEN LOWER TO IFR BETWEEN 19-23Z AS PRECIP RATES INCREASE. SFC TEMPS QUICKLY FALL TO BELOW FREEZING MID TO LATE AFTERNOON WHILE TEMPS ALOFT REMAIN ABOVE FREEZING BRINGING A TRANSITION TO LIGHT SLEET AND FREEZING RAIN LATE THIS AFTERNOON...THEN FREEZING DRIZZLE THIS EVENING WITH DRYING ALOFT. STRONG NLY WINDS WITH GUSTS AROUND 20-30 KT WILL BE POSSIBLE AT THE TERMINALS THIS AFTERNOON THROUGH THE EARLY EVENING. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 255 AM MONDAY...FLYING CONDITIONS WILL BE LESS THAN OPTIMAL FOR A GOOD PORTION OF THE EXTENDED PERIOD. A SERIES OF LOW PRESSURE WAVES WILL MOVE OFFSHORE WITH REDUCED CEILINGS AND VSBYS LIKELY FOR THE TUESDAY THROUGH THURSDAY PERIOD. THE INITIAL BAND OF RAIN WILL SPREAD BACK INTO THE REGION TUESDAY NIGHT AND CONTINUE THRU WEDNESDAY. ADDITIONAL RAINFALL WILL ACCOMPANY A STRONGER AREA OF LOW PRESSURE THURSDAY AND THURSDAY NIGHT. GUSTY WINDS WILL ALSO BE LIKELY ON THE BACKSIDE OF THESE WAVES OF LOW PRESSURE. HIGH PRESSURE BUILDS IN WITH DRIER AIR AND MORE VFR CONDITIONS FOR FRIDAY INTO SATURDAY. && .MARINE... SHORT TERM /THROUGH MONDAY NIGHT/... AS OF 1000 AM MONDAY...CURRENT MARINE IS IN GOOD SHAPE. ONLY MADE MINOR TWEAKS TO REFLECT CURRENT CONDITIONS. LATEST SURFACE ANALYSIS HAS THE ARTIC COLD FRONT ALONG CEDAR ISLAND. NORTH OF CEDAR ISLAND...WINDS HAVE SHIFTED TO NE 15 TO 20 KTS GUSTING UP TO 27 KTS. SEAS HAVE INCREASED IN OUR NORTHERN MARINE ZONE...5 TO 6 FT. SOUTH OF THE FRONT...WINDS REMAIN SW 10-20 KTS. COLD FRONT IS EXPECTED TO CONTINUE PUSH THROUGH THE WATERS...SOUTH OF THE REGION AROUND 2 PM. STRONG CAA IN NLY FLOW DEVELOPS BEHIND THE FRONT WITH GALE FORCE CONDITIONS DEVELOPING MID AFTERNOON THROUGH THE EVENING...ESPECIALLY IN GUSTS AROUND 35-40 KT. USED A BLEND OF THE PREVIOUS NWPS AND WAVEWATCH FOR SEAS...WEIGHING HIGHER TOWARD NWPS. SEAS WILL BUILD RAPIDLY THIS AFTN INTO TONIGHT WITH CAA SURGE...LIKELY PEAKING AT 10-12 FT NRN AND CENTRAL WATERS LATE TONIGHT. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 255 AM MONDAY...GUSTY WINDS AND ROUGH SEAS WILL CONTINUE THROUGH THE DAY ON TUESDAY BEFORE SUBSIDING IN THE EVENING AS HIGH PRESSURE STARTS TO BUILD DOWN THE EASTERN SLOPES OF THE MOUNTAINS. FROM WEDNESDAY INTO FRIDAY...SOLID SMALL CRAFT ADVISORY CONDITIONS ARE LIKELY AS A SERIES OF WAVES OF LOW PRESSURE MOVE OFFSHORE ALONG THE STALLED FRONT. THE STRONGEST OF THE WAVES MOVES OFFSHORE THURSDAY NIGHT THROUGH FRIDAY WITH STRONG SMALL CRAFT AND POTENTIAL GALE CONDITIONS POSSIBLE. PER WAVEWATCH GUIDANCE...SEAS WILL BUILD TO AS HIGH AS 8 TO 9 FEET...ESPECIALLY OVER THE CENTRAL WATERS THURSDAY INTO FRIDAY. HIGH PRESSURE BUILDS SOUTH OF THE COASTAL WATERS BY SATURDAY WITH DIMINISHING WINDS AND SEAS. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 11 AM EST TUESDAY FOR NCZ029-044>047-079>081-103. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST TUESDAY FOR NCZ090>095-098. WIND ADVISORY FROM 3 PM THIS AFTERNOON TO 1 AM EST TUESDAY FOR NCZ095-103-104. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 1 AM EST TUESDAY FOR AMZ135-152-154-156-158. GALE WARNING FROM 2 PM THIS AFTERNOON TO 1 AM EST TUESDAY FOR AMZ130-150. && $$ SYNOPSIS...SK NEAR TERM...SK/BM SHORT TERM...SK/BM LONG TERM...CTC AVIATION...CTC/SK MARINE...CTC/SK/BM
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
949 AM PST MON MAR 3 2014 .UPDATE... UPDATING AGAIN AS A BAND OF RAIN IS MOVING INTO LASSEN COUNTY THIS MORNING. RADAR/MODELS SHOW IT WELL WITH SOME CONVECTIVE ELEMENTS AND GOOD LOW-LEVEL CONVERGENCE. GFS/HRRR MOST AGGRESSIVE WITH THIS BAND TODAY AND RADAR/OBS TRENDS ARE DEFINITELY ALONG THESE WETTER SOLUTIONS. THEREFORE INCREASED POPS/QPF FOR LASSEN/PLUMAS COUNTIES THIS AFTERNOON WITH A TENTH TO 1/4 INCH OF RAIN LIKELY. SNOW LEVELS REMAIN HIGH, NEAR 7000 FEET AROUND TAHOE AND 6500 FEET FOR LASSEN/PLUMAS. ANY ACCUMULATION WILL BE LIGHT THERE AS WELL. THE BAND IS EXPECTED TO SLOWLY SAG SOUTH TONIGHT. MORE ON THAT THIS AFTERNOON. WALLMANN && .AVIATION... DISCUSSION BELOW STILL MOSTLY VALID, BUT LOOKING LESS LIKELY FOR ANY -SN AROUND KTRK/TVL. SNOW LEVELS LOOK TO REMAIN AT OR ABOVE 6500 FEET FOR THE DURATION OF THE EVENT TONIGHT. CHANCE OF ANY SNOW THAT WILL BRING IFR CIGS/VIS LOOKS TO BE LESS THAN 20 PCT NOW. WALLMANN && .PREVIOUS DISCUSSION... /ISSUED 625 AM PST MON MAR 3 2014/ UPDATE... RADAR IMAGERY SHOWS PCPN IN NRN CA GETTING CLOSE TO THE CWA THIS MORNING. WEB CAM AT BOGARD REST AREA IN WESTERN LASSEN COUNTY INDICATES WET PAVEMENT. THE PCPN IS LIKELY LIGHT ENOUGH RIGHT NOW TO BE MISSED BY RADAR. IN ANY EVENT PCPN IS MOVING IN AND THIS IS A BIT FASTER THAN ORIGINALLY FORECAST. HAVE UPDATED TO INCREASE POPS OVER THE NW CWA THIS MORNING. SNOW LEVELS SHOULD REMAIN HIGH FOR A WHILE RESULTING IN ONLY ACCUMULATIONS IN THE FAR WESTERN PORTION OF LASSEN COUNTY JUST EAST OF LASSEN PARK. IT IS LIKELY THAT POPS WILL NEED TO BE RAISED A BIT MORE TODAY OVER THE NORTH. ALSO BUMPED UP QPF A LITTLE...MORE IN LINE WITH THE 09 UTC SREF. 20 PREVIOUS DISCUSSION... /ISSUED 329 AM PST MON MAR 3 2014/ SYNOPSIS... A BAND OF SUBTROPICAL PACIFIC MOISTURE WILL BRING AREAS OF RAIN AND HIGH ELEVATION SNOW TO THE SIERRA AND WESTERN NEVADA LATER TODAY AND TONIGHT. MORE RAIN AND SNOW IS LIKELY IN THE SIERRA AND NORTHEAST CALIFORNIA BY WEDNESDAY NIGHT AS ANOTHER FAST MOVING LOW PRESSURE MOVES THROUGH. LATER THIS WEEK, DRY WEATHER WILL RETURN. ABOVE NORMAL TEMPERATURES ARE EXPECTED THROUGH THE UPCOMING WEEK. SHORT TERM... WATER VAPOR SATELLITE LOOP SHOWS A RATHER IMPRESSIVE BAND OF PACIFIC MOISTURE EXTENDING FROM HAWAII TO THE CENTRAL CA COAST. PRECIPITABLE WATER VALUES APPROACH 1.5 INCHES NEAR THE WEST COAST. HOWEVER, DESPITE THIS DECENT AMOUNT OF MOISTURE, FORCING IS LIMITED WHICH WILL LIMIT PRECIPITATION INTENSITY EAST OF THE SIERRA CREST AND INTO WESTERN NV THROUGH TONIGHT. WHILE THE 00Z MODEL GUIDANCE FAVORED THE BEST CHANCE FOR RAIN AND HIGH ELEVATION SNOW FOR LATER TONIGHT, THE 06Z GFS AND RECENT HRRR RUNS SPREAD MORE AREAS OF LIGHT PRECIP ACROSS THE REGION DURING THE DAY, WITH A GRADUAL SOUTHWARD PUSH TONIGHT. SNOW LEVELS ARE CURRENTLY PROJECTED TO RANGE FROM 6500 TO 7000 FEET, BUT GIVEN THE SUBTROPICAL AND EVEN TROPICAL ORIGIN OF THIS MOISTURE PLUME, THEY COULD RISE 500-1000 FEET HIGHER THAN THESE PROJECTIONS AT TIMES. LITTLE OR NO SNOW ACCUMULATION IS EXPECTED AROUND LAKE LEVEL IN THE TAHOE BASIN FOR THIS EVENT. MODEL QPF INDICATES UP TO 0.50 INCH OF LIQUID EQUIVALENT PRECIP NEAR THE SIERRA CREST WEST OF TAHOE, WHICH WOULD ROUGHLY TRANSLATE TO ABOUT 4 INCHES OF WET SNOW ABOVE 7000 FEET. A BROAD AREA OF RAINFALL BETWEEN 0.05 AND 0.20 INCH IS ALSO INDICATED DOWNSTREAM ACROSS MUCH OF WESTERN NEVADA. PRECIP CHANCES WERE INCREASED ACROSS THE HIGHWAY 50 AND I-80 CORRIDORS FOR LATE TONIGHT, BUT GIVEN THE LATEST MODEL TRENDS, RAIN CHANCES MAY NEED TO BE INCREASED SOONER IN THESE AREAS. FOR TUESDAY, SHOWERS ARE EXPECTED TO WIND DOWN AS FLAT RIDGE BUILDS OVER THE REGION. A WARMING TREND IS EXPECTED WITH DAYTIME TEMPS INCREASING TO THE LOWER 60S FOR MOST WESTERN NV VALLEYS. FOR WEDNESDAY AND WEDNESDAY NIGHT, FURTHER WARMING IS LIKELY AS WINDS INCREASE AHEAD OF NEXT TROUGH APPROACHING THE WEST COAST. THERE IS SOME UNCERTAINTY AGAIN WITH ONSET TIME OF RAIN AND HIGH ELEVATION SNOW AS THE ECMWF BRINGS SOME LIGHT PRECIP TO NORTHEAST CA DURING THE DAY, WHILE THE GFS HOLDS OFF ON MEASURABLE PRECIP UNTIL WEDNESDAY NIGHT. THE MAJORITY OF THE GUIDANCE IS INDICATING STRONGER PRECIP SHADOWING EAST OF THE SIERRA CREST, WHILE IN THE SIERRA THE SNOW LEVELS ARE LIKELY TO BE EVEN HIGHER THAN THE FIRST PRECIP EVENT FOR TODAY AND TONIGHT. THE MAIN IMPACT IN WESTERN NV IS MORE LIKELY TO BE A PERIOD OF GUSTY WINDS WEDNESDAY NIGHT AHEAD OF THE TROUGH PASSAGE. MJD LONG TERM...THURSDAY THROUGH SUNDAY... ONLY SIGNIFICANT CHANGES MADE TO THE EXTENDED FORECAST WERE TO BUMP UP POPS THURSDAY MORNING AND ADD POPS FOR SUNDAY. MEDIUM RANGE DETERMINISTIC MODELS AND GEFS ENSEMBLE MEMBERS ALL BRING A SHORT WAVE TROUGH THROUGH THE NRN PART OF THE REGION THURSDAY WITH A WEAK COLD FRONT PASSING THROUGH MOST OF THE CWA BEFORE STALLING AND FURTHER WEAKENING OVER THE SRN 1/3 OF THE REGION. WINDS SHOULD PICK UP AHEAD OF THIS SYSTEM...BUT STAY LESS THAN ADVISORY CRITERIA. WHILE QPF OVER FAR NRN AREAS IS BETTER THAN 0.50 INCHES...SNOW LEVELS WITH THIS SYSTEM START FAIRLY HIGH. THUS...ACCUMULATIONS SHOULD BE LIMITED TO THE HIGHER ELEVATIONS AND FOR NOW WE DO NOT SEE WINTER WEATHER ADVISORIES FOR THIS SYSTEM. OF COURSE...THIS COULD ALL CHANGE. SHORT WAVE RIDGE BUILDS FOR FRIDAY THEN SLIDES EAST SATURDAY AS ANOTHER TROUGH DIGS INTO THE ERN PACIFIC. AFTER WARM TEMPS ON THURSDAY THERE WILL BE A BRIEF COOL DOWN ON FRIDAY...THEN TEMPS BUMP UP AGAIN FOR SATURDAY. SATURDAY COULD BE ANOTHER ONE OF THOSE DAYS WHERE WINDS GUST INTO THE 40 MPH RANGE...ESPECIALLY FROM HWY 50 NORTHWARD. THE NEXT SHORT WAVE MOVES INTO THE COAST ON SUNDAY. THIS SYSTEM APPEARS TO HAVE A DECENT MOISTURE TAP AND SHOULD HAVE GOOD ENOUGH DYNAMICS TO SQUEEZE OUT PCPN OVER THE NRN 2/3RDS OF THE CWA. THE BEST PCPN CHANCES FOR NOW LOOK TO BE FROM THE TAHOE BASIN NORTHWARD INTO NE CA. EVEN SO...THIS FAR OUT PCPN AMOUNTS ARE QUITE VARIABLE WITH ECMWF SHOWING THE BEST AT AROUND 0.35 INCHES OVER THE NW CWA. ALL THIS IS SUBJECT TO CHANGE AS WE APPROACH THE EVENT NEXT WEEKEND SO RIGHT NOW THE CONFIDENCE IS ONLY MEDIUM IN MUCH DEVELOPING WITH THIS SYSTEM. 20 AVIATION... PRECIPITATION IS SPREADING INTO THE NRN CA COAST THIS MORNING. AS THE DAY PROGRESSES THIS PRECIPITATION SHOULD SPREAD OVER THE NRN FORECAST AREA. VFR CONDITIONS FOR THE AREA THIS MORNING WILL GIVE WAY TO MVFR CONDITIONS BY EARLY AFTERNOON NORTH OF THE TAHOE BASIN. IFR/MVFR CONDITIONS WILL DEVELOP FROM THE TAHOE BASIN NORTH ACROSS NE CA AND FAR NW NV BY EARLY EVENING WITH MOST MOUNTAINS OBSCURED. FARTHER SOUTH AND EAST VFR CONDITIONS WILL PERSIST LONGER. SNOW LEVELS START FAIRLY HIGH TODAY SO ANY TERMINALS THAT PICK UP PRECIPITATION THROUGH THE EARLY EVENING HOURS SHOULD SEE ALL RAIN. SNOW LEVELS WILL BRIEFLY DROP TO THE VALLEY FLOORS AROUND THE LAKE TAHOE BASIN AND PARTS OF PLUMAS AND LASSEN COUNTIES THIS EVENING IN HEAVIER PRECIPITATION BANDS. THIS WILL DRIVE KTRK AND KTVL TO IFR CONDITIONS FOR A BRIEF PERIOD OF TIME AFTER 4/02 UTC...BUT ANY ACCUMULATIONS ON THE RUNWAYS WILL BE MINIMAL. RIDGE GUSTS SHOULD BE NO WORSE THAN 50 MPH TODAY AND THIS EVENING. SHOWERS LINGER NEAR THE SIERRA CREST BY EARLY TUESDAY MORNING BUT MOST OTHER AREAS SEE A DECREASE IN CLOUDS AS A WEAK SHORT WAVE RIDGE BUILDS OVER THE AREA. ANOTHER TROUGH OF LOW PRESSURE BRINGS A RENEWED CHANCE FOR PRECIPITATION TO THE REGION BY WEDNESDAY/WEDNESDAY NIGHT. 20 && .REV WATCHES/WARNINGS/ADVISORIES... NV...NONE. CA...NONE. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS PUEBLO CO
323 PM MST MON MAR 3 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 323 PM MST MON MAR 3 2014 WEAK SHORTWAVE EMBEDDED WITHIN NORTHWEST FLOW ALOFT IS EXITING EASTERN CO LATE THIS AFTERNOON WITH DRYING NOTED IN WV LOOPS BEHIND IT. ISOLATED MAINLY OROGRAPHICALLY FORCED SNOW SHOWERS WILL COME TO AN END ACROSS THE CENTRAL MOUNTAINS THIS EVENING. MAIN CHALLENGE WILL BE LOW TEMPERATURES TONIGHT. LOWER ARKANSAS RIVER VALLEY STRUGGLED TO WARM INTO THE 30S TODAY...AND WITH CLEARING SKIES AND WANING HIGH LEVEL CLOUD COVER...SUSPECT THESE AREAS MAY COOL QUICKLY THIS EVENING. OTHER AREAS HOWEVER WILL SEE WAA WITH LEE TROFFING OVERNIGHT AND SHOULD REMAIN ON THE WARM SIDE...WITH LOWER 30S FOR PORTIONS OF THE I-25 CORRIDOR. THERE IS SOME CONCERN FOR PATCHY FOG DEVELOPING ACROSS THE LOWER ARKANSAS RIVER VALLEY WITH NAM12 AND RAP SUGGESTING FOG FROM ROUGHLY KLHX EASTWARD. HOWEVER...ALSO LOOKING AT NEXT ROUND OF MID/HIGH LEVEL MOISTURE STREAMING INTO THE GREAT BASIN. DISTANCE SPEED TOOL PUTS THIS INTO THE AREA BY 03-04Z...AND IF CLOUD COVER IS THICK ENOUGH...MAY PREVENT FOG FROM FORMING. HAVE DECIDED TO LEAVE FOG OUT OF THE GRIDS FOR NOW. THE NEXT SHORTWAVE/UPPER LEVEL JET IS CURRENTLY MOVING ONTO THE CEN/NRN CA COAST. THIS SYSTEM WILL BE APPROACHING THE AREA BY TUESDAY AFTERNOON SPREADING ANOTHER ROUND OF SNOW INTO THE WESTERN MOUNTAINS WITH LEE TROFFING AND POCKETS OF BREEZY WEST WINDS ACROSS THE I-25 CORRIDOR. THIS SHOULD YIELD MAX TEMPERATURES IN THE 50S TO AROUND 60 ON TUESDAY...EVEN ACROSS THE SOUTHEAST PLAINS WHERE STRONGER SOUTHERLY FLOW AHEAD OF THE SFC LOW WILL AID IN DEEPER MIXING. SFC COLD FRONT WILL DROP SOUTH OF THE PALMER DIVIDE AFTER 21Z...SPREADING SOME SHOWERS INTO THE PIKES PEAK REGION DURING THE LATE AFTERNOON. LAPSE RATES LOOK FAIRLY STEEP...SO SHOWERS ARE LIKELY TO BE CONVECTIVE IN NATURE AND WOULD NOT BE SURPRISED TO SEE SOME POCKETS OF HEAVY WET SNOW WITH THE STRONGER SHOWERS. FORTUNATELY THEY DO NOT APPEAR TO LAST FOR LONG WHICH SHOULD LIMIT ACCUMULATIONS. THE CENTRAL MOUNTAINS COULD PICK UP A QUICK 1-2 INCHES OF SNOW LATE TUESDAY AFTERNOON. -KT .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 323 PM MST MON MAR 3 2014 TUESDAY NIGHT-WEDNESDAY...SOME DIFFERENCES ON AMPLITUDE AND STRENGTH OF A SHORT WAVE TRANSLATING ACROSS THE STATE LATE TUESDAY NIGHT...WITH THE LATEST NAM CONTINUING TO BE THE FURTHEST NORTH WITH THE SYSTEM AND IS THEREFORE PRINTING OUT MUCH LESS QPF ACROSS SOUTH CENTRAL AND SOUTHEAST COLORADO. HOWEVER...THE 12Z RUNS OF THE GFS AND ECMWF HAVE ALSO TRENDED LESS AMPLIFIED AND A TAD FURTHER NORTH WITH THE SYSTEM THAN THEIR PREVIOUS RUNS...THOUGH ARE STILL PRINTING OUT MORE PRECIPITATION ACROSS THE AREA WITH BETTER MOISTURE AND UVV WITH LF QUAD OF ASSOCIATED JET. THE NAMS TRACK RECORD OVER THE PAST FEW MONTHS HAS BEEN LESS THAN STELLAR...AND WITH THAT SAID...HAVE CONTINUED TO KEEP LIKELY AND HIGH CHANCE POPS ACROSS THE CENTRAL MTS THROUGH THE PIKES PEAK REGION THROUGH THE EVENING...WITH CHANCE AND SLIGHT CHANCE POPS ACROSS THE REST OF THE HIGHER TERRAIN THROUGH THE FAR EASTERN PLAINS. QUICK MOVEMENT OF THE SYSTEM WILL LIMIT ACCUMULATIONS ACROSS THE CENTRAL MTS WITH 1 TO 3 INCHES POSSIBLE THROUGH THE NIGHT. GENERALLY LIGHT ACCUMS POSSIBLE ACROSS THE REST OF THE HIGHER TERRAIN AND PALMER DVD WITH PRECIPITATION ACROSS THE PLAINS STARTING AS RAIN BEFORE BECOMING MIXED WITH AND CHANGING TO SNOW THROUGH THE EVENING AS COLDER AIR BEHIND ASSOCIATED COLD FRONT MOVES ACROSS THE AREA. AGAIN...WILL NEED TO SEE HOW AMPLIFIED THIS SYSTEM IS AS IT MOVES ACROSS THE STATE TOMORROW NIGHT...WHICH COULD LEAD TO MORE OR LESS PRECIPITATION ACROSS THE AREA...ESPECIALLY THE SOUTHERN MTS AND PLAINS. WEDNESDAYS HIGHS LOOK TO BE SLIGHTLY COOLER THAN TUESDAY...THOUGH STILL AT OR SLIGHTLY BELOW SEASONAL AVERAGES. WEDNESDAY NIGHT-THURSDAY NIGHT...WARMER WESTERLY FLOW PROGGED ACROSS THE AREA THROUGH THE DAY THURSDAY AS SHORT WAVE RIDGING BUILDS ACROSS THE STATE AHEAD OF THE NEXT DISTURBANCE MOVING ONSHORE ACROSS THE WEST COAST. PATTERN KEEPS THE AREA DRY THROUGH THE PERIOD...SAVE SOME SLIGHT POPS ACROSS THE HIGHER ELEVATIONS OF THE CENTRAL MTS THURSDAY NIGHT WITH INCREASING MOISTURE WITHIN THE OROGRAPHIC FLOW. LOWS WEDNESDAY NIGHT LOOK TO BE ON THE MILD SIDE...ESPECIALLY ACROSS THE LOWER SLOPES OF THE EASTERN MTS WITH WESTERLY GAP FLOWS DEVELOPING OVERNIGHT. THURSDAY CONTINUES TO BE THE WARMEST DAY OF THE WEEK...WITH HIGHS IN THE 60S TO LOWER 70S ACROSS THE LOWER ELEVATIONS...40S AND 50S ACROSS THE MTS AND HIGH VALLEYS AND MAINLY 30S AT THE PEAKS. FIRE WEATHER CONCERNS INCREASE FOR AREAS ALONG AND WEST OF THE I-25 CORRIDOR THURSDAY AFTERNOON WITH EXPECTED BREEZY WESTERLY WINDS. FRIDAY-MONDAY...LATEST MODELS HAVE BEEN TRENDING TOWARDS A MORE AMPLIFIED AND SLOWER SYSTEM DIGGING ACROSS THE CENTRAL AND SOUTHERN ROCKIES FRIDAY AND SATURDAY....WITH THE ECMWF STILL INDICATING A CLOSED LOW DEVELOPING ACROSS NORTH CENTRAL NEW MEXICO LATE FRIDAY NIGHT. THIS TRACK REMAINS FAVORABLE FOR DECENT PRECIPITATION ACROSS EASTERN COLORADO...ESPECIALLY THE SOUTHEASTERN MTS AND SOUTHERN I-25 CORRIDOR LATE FRIDAY AFTERNOON THROUGH EARLY SATURDAY...WITH INCREASING EAST TO NORTHEAST H7-H5 FLOW. HIGH TEMPERATURES ON FRIDAY REMAIN HIGHLY DEPENDENT ON HOW FAST THE ASSOCIATED COLD FRONT MOVES ACROSS THE AREA. COOLER TEMPERATURES ARE THEN EXPECTED ACROSS THE AREA ON SATURDAY...WITH DRIER AND WARMER WEATHER FOR SUNDAY AND MONDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 323 PM MST MON MAR 3 2014 VFR CONDITIONS EXPECTED AT THE TAF SITES THROUGH THE NEXT 24 HOURS WITH GENERALLY LIGHT WINDS. COLD FRONT WILL MOVE SOUTH OF THE PALMER DIVIDE TUESDAY AFTERNOON SPREADING LOWER CIGS INTO THE KCOS AREA ASSOC WITH SHOWERS. FOR NOW...CIGS LOOK TO REMAIN IN THE VFR CATEGORY. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KT LONG TERM...MW AVIATION...KT
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1153 AM EST MON MAR 3 2014 .SYNOPSIS... LOW PRESSURE IN NORTH CAROLINA WILL HEAD EAST AND OUT TO SEA LATE TODAY. HIGH PRESSURE WILL FOLLOW INTO THE MID ATLANTIC STATES TUESDAY THEN ITS PRIMARY CENTER SHIFTS TO MAINE BY THURSDAY. LOW PRESSURE IS FORECAST TO PASS WELL TO OUR SOUTHEAST AND EAST FRIDAY. A COLD FRONT FROM THE NORTHWEST IS THEN EXPECTED TO PASS THROUGH THE REGION LATE SATURDAY WITH A CHANCE LOW PRESSURE FORMS ON THAT FRONT NEAR THE MID ATLANTIC COAST. HIGH PRESSURE FOLLOWS BY EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WAS ABLE TO SHAVE ANOTHER LAYER OF WARNING OFF LEAVING MOST OF THE DELMARVA AND SOUTHEAST NEW JERSEY INTACT FOR THE NEXT FEW HOURS. REGIONAL RADAR IS STILL SHOWING SOME ENHANCED REFLECTIVITIES ACROSS THE SOUTHERN HALF OF OUR AREA BUT THE VERY DRY SUB-CLOUD LAYER WILL PREVENT MUCH, IF ANY, OF THIS MOISTURE FROM REACHING THE SURFACE. DID ADJUST SNOW TOTALS DOWNWARD A BIT AND EXPECTING OUR MAXIMUM AMOUNTS TO BE AROUND 8 INCHES IN CENTRAL DELMARVA. THE BEST OMEGA WITHIN THE SNOW GROWTH SEEMS TO BE...AS PER THE RUC TRICKLING THROUGH CENTRAL AND SOUTHERN DELMARVA INTO SOUTHERN NEW JERSEY. THIS THEN ALL SHIFTS TOWARDS THE SOUTHEAST THROUGH THE EARLY AFTERNOON HOURS AND THE SNOW BEGINS TO WIND DOWN. WINDS WILL BECOME GUSTY FROM THE NORTH AS THE ARCTIC AIR SETTLES IN. TEMPERATURES WILL PROBABLY NOT RISE MUCH TODAY...INSTEAD MOSTLY HOLDING STEADY EARLY THEN FALLING LATER THIS AFTERNOON. WIND CHILL VALUES WILL START THE DAY MOSTLY IN THE TEENS...BUT DROP INTO THE SINGLE DIGIT READINGS LATE. WIND CHILL READINGS ABOUT 10 COLDER OVER THE HIGHER ELEVATIONS OF NE PA. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/... THE SNOW ASSOCIATED WITH THE LOW PRESSURE WAVE WILL HAVE MOVED OFFSHORE BY EARLY TONIGHT. ARCTIC HIGH PRESSURE WILL BUILD ACROSS THE AREA OVERNIGHT. THIS WILL PRODUCE FAIR WEATHER AND MOSTLY CLR SKIES. GOOD RADIATIONAL COOLING AND DIMINISHING NORTH WINDS WILL ALLOW TEMPERATURES TO FALL TO NEAR RECORD LEVELS OVERNIGHT. LOWS WILL BE SUB-ZERO OVER THE SRN POCONOS AND NRN NJ AND IN THE SINGLE DIGITS ELSEWHERE. WIND CHILL VALUES WILL BE BETWEEN -10 AND -15 ACROSS THE HIGH ELEVATIONS OF THE SRN POCONOS AND 0 TO -10 ELSEWHERE. THESE WIND CHILL VALUES ARE JUST SHORT OF WSW (WIND CHILL) ADVISORY CRITERIA. WE WILL NOT ISSUE AND WSW PRODUCTS FOR THIS NOW...BUT KEEP IN MIND THAT IT MAY BE NEEDED THIS AFTERNOON IF WINDS END UP BEING HIGHER...OR TEMPS FCST BECOMES LOWER. && .LONG TERM /TUESDAY THROUGH SUNDAY/... 500MB: RELATIVELY INNOCUOUS THROUGH WEDNESDAY NIGHT AS THE VERY COLD AIRMASS MODIFIES. THEN A SPLIT FLOW DEVELOPS FOR A TIME LATE THIS WEEK AS A STRONG SHORT WAVE SWINGS THROUGH THE SOUTHEASTERN USA...SHIFTING OFFSHORE BY THE WEEKEND. UNCERTAINTY EXISTS REGARDING TIMING AND STRENGTH OF THE WEEKEND SHORT WAVE MOVING EWD FROM THE MIDWEST AND OHIO VALLEY. TEMPERATURES...AROUND 20 DEGREES BELOW NORMAL TUESDAY...15 BELOW NORMAL WEDNESDAY WARMING TO NORMAL OR A BIT ABOVE FRIDAY AND SATURDAY BEFORE POSSIBLY COOLING AGAIN EARLY NEXT WEEK. FORECAST BASIS...MOSTLY 00Z/3 GFS MOS GUIDANCE TUE-WED NIGHT AND THEN 0543Z/3 WPC GRIDDED GUIDANCE THAT WAS MODIFIED USING ECMWF OP GUIDANCE. THE DAILIES... TUESDAY AND MOST OF WEDNESDAY...DRY WITH VARIABLE HIGH CLOUD COVER. WEDNESDAY NIGHT INTO THURSDAY NIGHT...POTENTIAL BRUSH WITH THE SE USA LOW? QUITE UNCERTAIN. SINCE THE HIGH BECOMES STRONG NEAR MAINE BY THURSDAY...ENOUGH ONSHORE FLOW TO DEVELOP CONSIDERABLE CLOUDINESS WITH POTENTIAL FOR AREAS OF LIGHT MIXED PCPN. FRIDAY...FOR NOW LOOKS DRY WITH THE SE USA LOW HEADING SEAWARD. NEXT WEEKEND...LOW PRESSURE MAY DEVELOP ON THE COLD FRONT PASSING THRU THE REGION WHICH WOULD COMPLICATE MATTERS...SO HAVE A LOW CHC OF PCPN. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. CONDITIONS WERE CONTINUING TO IMPROVE FROM NORTH TO SOUTH AT 1400Z. KRDG, KABE, KTTN AND KPNE WERE VFR AND THEY WILL REMAIN VFR THROUGH THE REMAINDER OF THE TAF PERIOD. THE SNOW SHOULD END WITH CONDITIONS IMPROVING INTO THE VFR CATEGORY BY 1600Z AT KPHL, BY 1700Z AT KILG AND BY 1800Z AT KMIV AND KACY. A NORTH NORTHWEST WIND AROUND 10 TO 12 KNOTS THIS AFTERNOON WILL GUST INTO THE LOWER 20S. THE WIND IS FORECAST TO DIMINISH INTO THE 4 TO 8 KNOT RANGE FOR TONIGHT WITH NO GUSTS ANTICIPATED AT THAT TIME. OUTLOOK... TUESDAY THROUGH WEDNESDAY MORNING...VFR OCNL CIGS AOA 10000 FT. LIGHT WIND. WEDNESDAY AFTERNOON AND NIGHT...POSSIBLE MVFR CIGS DEVELOPING WITH A SMALL CHANCE OF IFR CONDS IN SPOTTY PCPN/FREEZING DRIZZLE AT NIGHT? WIND BECOMING NE G 10-15 KT. CONFIDENCE BELOW AVG. THURSDAY...VFR CIGS WITH A LOW CHANCE OF MVFR CONDS IN RAIN/SNOW SHOWERS OR SPOTTY FREEZING DRIZZLE. NE WIND. CONFIDENCE BELOW AVG. FRIDAY...PROBABLY VFR. && .MARINE... WEAK LOW PRESSURE WILL MOVE BY TO THE SOUTH TODAY AND TONIGHT...WHILE STRONG HIGH PRESSURE BUILDS IN FROM THE NORTH. THE PRESSURE GRADIENT AND THE COLD AIR ADVECTION WILL BE ENOUGH TO CONTINUE WITH THE SCA FLAG FOR THE WATERS TODAY ACROSS ALL WATERS...AND TONIGHT FOR MOST OF THE OCEAN WATERS. NO CHANGES WILL BE MADE ATTM. SNOW/RAIN WILL BE ON THE WATERS THIS MORNING AND AFTERNOON...ESPECIALLY ACROSS THE DEL/SRN NJ/DEL BAY AREAS...LIGHTER AMOUNTS FURTHER NORTH. FREEZING SPRAY EXPECTED LATER TODAY AND TONIGHT. OUTLOOK... TUESDAY MORNING...A SMALL CRAFT ADVISORY WILL CONTINUE ON OUR OCEAN WATERS FROM OFF MANASQUAN INLET TO OFF FENWICK ISLAND DUE TO NORTHERN WIND GUSTS AROUND 25 KNOTS AND WAVE HEIGHTS NEAR 5 FEET. LIGHT TO MODERATE FREEZING SPRAY IS LIKELY. TUESDAY AFTERNOON THROUGH EARLY WEDNESDAY NIGHT...NO MARINE HEADLINES ARE ANTICIPATED. LATE WEDNESDAY NIGHT INTO FRIDAY...SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE, MAINLY ON OUR OCEAN WATERS. && .CLIMATE... THE FOLLOWING HAS BEEN DEVELOPED FROM MANY RESOURCES OVER THE PAST WEEK OR SO. KABE...THE CURRENT 38 CONSECUTIVE DAYS OF SNOW ON THE GROUND WILL PROBABLY EXTEND TO AT LEAST 45 DAYS (FRIDAY MARCH 7TH) WHICH WOULD EQUAL THE 4TH LONGEST CONSECUTIVE DAY STREAK WITH SNOW ON THE GROUND SINCE RECORDS BEGAN IN ALLENTOWN IN 1923. KABE CONSECUTIVE DAY RANKING 1. 78 DAYS ENDING MARCH 22 1994. 2. 59 DAYS ENDING MARCH 13 1978 3 TIE 49 DAYS ENDING FEB 12 1977 AND FEB 19 1925 4. 45 DAYS ENDING MARCH 4 1936 5. 43 DAYS ENDING FEB 2 1970 RECORD LOWS (POR EQUAL PERIOD OF RECORD) MARCH 3 MARCH 4 (AT 1159PM?) ACY 5-2009 3-2009 POR 1874 PHL 10-1886 7-1943 POR 1872 ILG 9-2009/1925 5-1943 POR 1894 ABE 8-1950/1925 3-1943 POR 1922 TTN 5-1868 1-1868 POR 1865 GED 9-2009 6-2009 POR 1948 RDG 9-2009/1980/1925 7-1943 AND 1913 POR 1869 MPO -2 2003 -6-1943 POR 1865 SEASONAL SNOWFALL RANKINGS AS OF 1 AM EST 3/3/14 PHL 59.5 #3 OFFICIAL RECORDS BACK TO 1884 1. 78.7 2009-2010 2. 65.5 1995-1996 3. 59.5 2013-2014 4. 55.4 1898-1899 ABE 66.9 #4 OFFICIAL RECORDS BACK TO 1922 1. 75.4 1993-1994 2. 71.4 1995-1996 3. 67.2 1966-1967 4. 66.9 2013-2014 5. 65.2 1960-1961 ILG 48.4 #4 OFFICIAL RECORDS BACK TO 1894 1. 72.8 2009-2010 2. 49.5 1957-1958 3. 48.8 1906-1907 (MISSING DAYS IN THE DATABASE FOR THIS SEASON) 4. 48.4 2013-2014 5. 46.1 2002-2003 && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR NJZ021>025. DE...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR DEZ002. WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR DEZ003- 004. MD...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR MDZ012- 015-019-020. MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR ANZ451>455. SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430- 450. SMALL CRAFT ADVISORY UNTIL 11 PM EST THIS EVENING FOR ANZ431. && $$ SYNOPSIS...DRAG NEAR TERM...HEAVENER/O`HARA SHORT TERM...O`HARA LONG TERM...DRAG AVIATION...DRAG/IOVINO/O`HARA MARINE...DRAG/O`HARA CLIMATE...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
406 PM CST MON MAR 3 2014 .DISCUSSION... 319 PM CST THE PRIMARY FORECAST CONCERNS ARE FOR SNOW CHANCES...NAMELY TUE NIGHT AND WED...AND THEN TEMPERATURES OVER MUCH OF THIS WEEK AS IT GETS CHALLENGING WEIGHING FACTORS SUCH AS CLOUD COVER...INCREASING MARCH SUN ANGLE...SNOW COVER...AND FLUCTUATING TEMPERATURES ALOFT. TONIGHT AND TUESDAY MORNING... A STRONG AND BARELY MODIFIED ARCTIC HIGH PRESSURE OF 1035MB IS IN PLACE OVER THE LOCAL AREA GOING INTO THIS EVE. WHILE HEIGHTS ARE SLOWLY RISING ALOFT...THE NEXT IN A SERIES OF SYSTEMS WITHIN FAST PACED WNW FLOW IS APPROACHING THE AREA. THE CENTER OF THE SHORT WAVE IMPULSE ON WATER VAPOR IS SEEN ACROSS NORTH DAKOTA WITH MID CLOUD ALREADY INTO SOUTHWEST WI. THE RAP AND NAM SOLUTIONS OF SIMULATED WATER VAPOR HAVE A GOOD HANDLE ON THIS AND HAVE INCORPORATED THAT APPROACH INTO SKY COVER FORECASTS TONIGHT...WITH CONDITIONS BECOMING CLOUDY BY MID-EVE. THIS WILL MAKE IT TRICKY AS THE SYNOPTIC SCENARIO WOULD FAVOR RAPIDLY FALLING TEMPS THIS EVE BUT THE CLOUDS WILL LIKELY OFFSET THIS SOME. HAVE LEANED THE MILDER ROUTE...ESPECIALLY NORTH OF I-80...WITH A LIMITED DROP-OFF THIS EVE AND THEN TEMPS CLIMBING OVERNIGHT. HAVE THE COOLEST TEMPS FORECAST ACROSS EAST CENTRAL IL INTO NORTHWEST IN WHERE MID CLOUDS WILL TAKE THEIR LONGEST TO THICKEN. THE FORCING FOR PRECIP WILL BE PRIMARILY TO THE EAST AND NORTH OF THE CENTER OF CIRCULATION TO THIS SHORT WAVE...AS IT OFTEN IS WITH THESE PROGRESSIVE ARE LOW AMPLITUDE NORTHWEST FLOW SYSTEMS. THUS AM NOT TOO EXCITED FOR SNOW INTO THE FORECAST AREA...ESPECIALLY GIVEN THE DRY DEEP ATMOSPHERE IN PLACE. SO HAVE LEANED AWAY FROM THE MORE ROBUST 12Z NAM AND CLOSER TO THE RAP AND GLOBAL MODELS...WITH POSSIBLY A DUSTING ALONG AND NORTH OF I-88. TUESDAY AND WEDNESDAY... WHILE THERE MAY BE SOME LIGHT SNOW/FLURRIES EARLY IN NORTHEAST IL...THE DAYTIME TUESDAY LOOKS MAINLY DRY WITH A GAP BETWEEN WAVES LIKELY ALLOWING FOR SOME SUNSHINE. WITH A MUCH WARMER STARTING POINT THAN TODAY...HIGHS LOOK TO REBOUND MORE TOWARD WHERE THEY SHOULD BE GIVEN THE 925MB TEMPS...BUT FAR FROM WHERE THEY SHOULD BE GIVEN THE TIME OF YEAR. HAVE FORECAST HIGHS IN THE LOWER TO MID 20S. THE NEXT SHORT WAVE HAS A BETTER PATH TO FAVOR OUR AREA AND ALSO HAS MORE ELONGATED /LONGER LASTING/ FORCING TIED TO ITS UPPER DYNAMIC SUPPORT AND FRONTOGENESIS. GUIDANCE IS IN FAIR AGREEMENT WITH THE AREA SEEING SNOW...NAMELY OVERNIGHT TUE NIGHT INTO WED MORNING...AND IT MAKES GOOD SENSE GIVEN THE PARAMETERS. SO CONTINUE TO INCREASE POPS. THE SNOW LOOKS TO BE FAIRLY EFFICIENT GIVEN TOP DOWN METHOD AND TEMPERATURE PROFILES...WITH MODEST RATES AT TIMES WHEREVER THAT WEST-TO-EAST BAROCLINIC GRADIENT OF THE SYSTEM PASSES ACROSS. HAVE 1-2.5 INCHES FORECAST FOR A LOT OF THE AREA. HOW MUCH A SECONDARY SHORT WAVE MOVING ACROSS THE MISSOURI RIVER VALLEY GETS INVOLVED WEDNESDAY WILL BE KEY AS WELL...AS THAT COULD BOOST AMOUNTS IN THE SOUTHERN FORECAST AREA. ALSO OF NOTE IS POTENTIAL LAKE EFFECT SETUP ONCE AGAIN INTO WEDNESDAY AFTERNOON AND NIGHT FOR NORTHEAST IL. MILDER TEMPERATURES THAN THIS MORNING WOULD POINT TOWARD NOT AS GOOD OF INSTABILITY...HOWEVER THERE ARE SIGNS OF CONVERGENCE AND BETTER BOUNDARY LAYER RH...AND FOR THAT HAVE CONTINUED POPS ACROSS CHICAGO INTO WEDNESDAY NIGHT. MTF THURSDAY AND BEYOND... LARGE SCALE PATTERN IN THE EXTENDED WILL CONTINUE TO SUPPORT WELL BELOW NORMAL HIGH/LOW TEMPS...WITH LOW CHANCE POSSIBILITIES FOR PRECIP DURING THE PERIOD. GENERAL WEST/NORTHWEST FLOW ALOFT WILL USHER IN SEVERAL WAVES OF ENERGY THROUGH MID WEEK...WITH MODELS IN FAIR AGREEMENT WITH THESE FEATURES AND RESULTANT QPF. ALTHOUGH THE GFS APPEARS TO VARY WITH THE STRENGTH OF A MORE DEFINED SHORTWAVE TROUGH BY LATE WEDNESDAY INTO THURSDAY...AND THEN IS A TAD MORE BULLISH WITH ITS ASSOCIATED PRECIP. NONETHELESS...WHATEVER DEVELOPS SHOULD BE RATHER PROGRESSIVE AND QUICKLY EXIT...AND WITH THERMAL PROFILES SUPPORTIVE OF ALL SNOW DURING THIS PERIOD. PATTERN TRIES TO BECOME MORE ACTIVE LATE IN THE WORK WEEK WHILE SHOWING SIGNS OF SLIGHT WARMING...AS LARGE SCALE PATTERN BECOMES MORE AMPLIFIED OVER THE CENTRAL CONUS WHILE LARGE VORT MAX SHIFTS EAST THROUGH SOUTHERN CANADA. TAIL END OF THIS ENERGY WILL APPROACH THE REGION BY LATE IN THE WORK WEEK...AS WINDS BACK AND WAA OCCURS OUT AHEAD OF IT. THIS SHOULD SUPPORT SOME WARMER TEMPS IN THE MID TO UPPER 30S BY FRIDAY...WITH A MIX OF RAIN AND SNOW THEN POSSIBLE AS ASSOCIATED SURFACE TROUGH/FRONT MOVE OVER THE AREA. ALTHOUGH...THIS WARMING WILL BE BRIEF AS COLDER AIR SHOULD FILTER IN ON THE BACKSIDE OF THIS SYSTEM WITH WELL BELOW NORMAL TEMPS ONCE AGAIN EXPECTED INTO THE WEEKEND. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 22Z... * LIGHT VARIABLE WINDS...MAINLY EAST-SOUTHEAST THIS AFTERNOON WITH SLIGHT LAKE MICHIGAN INFLUENCE. * CHANCE OF SNOW LATE TONIGHT INTO EARLY TUESDAY MORNING. MVFR CONDITIONS POSSIBLE FOR A TIME TOWARD MORNING. RATZER //DISCUSSION...UPDATED 18Z... HIGH PRESSURE CONTINUES TO SHIFT EAST ACROSS THE REGION...WHILE LAKE EFFECT SNOW SHOWERS CONTINUE TO DIMINISH. ONLY ANTICIPATE THESE LIGHT SNOW SHOWERS TO PERSIST FOR THE NEXT COUPLE OF HOURS...WHILE MVFR CEILINGS ALSO PERSIST. THEN AS SOON AS THIS DISSIPATES...MID/HIGH LEVEL CLOUD COVER WILL BEGIN TO INCREASE OUT AHEAD OF THE NEXT SYSTEM. LOWERING TRENDS WILL OCCUR TONIGHT INTO TUESDAY MORNING...WHILE SNOW CHANCES ALSO INCREASE. WENT A TAD MORE PESSIMISTIC WITH THIS SNOW AND VIS TONIGHT...BUT NOT AS AGGRESSIVE AS CONDITIONS COULD POSSIBLY BE DUE TO REMAINING UNCERTAINTY. WILL NEED TO MONITOR POSSIBLE HEAVIER SNOW AND LOWER VIS FOR TIME LATE TONIGHT/EARLY TUESDAY MORNING. LIGHT NORTHEAST WINDS WILL VEER TO THE EAST AND SOUTHEAST THIS AFTERNOON AND THIS EVENING...BEFORE BECOMING MORE SOUTHERLY OVERNIGHT INTO TUESDAY. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 22Z... * MEDIUM-HIGH CONFIDENCE IN WIND TRENDS. * MEDIUM CONFIDENCE IN LIGHT SNOW TONIGHT. RODRIGUEZ/RATZER //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT THROUGH THURSDAY...MAINLY VFR WITH PERIODIC CHANCES OF LIGHT SNOW AND MVFR/IFR...ESPECIALLY TUESDAY NIGHT AND WEDNESDAY. FRIDAY AND SATURDAY...CHANCE OF LIGHT RAIN OR SNOW FRIDAY AND A CHANCE OF SNOW SATURDAY. PERIODS OF MVFR/IFR POSSIBLE. MDB && .MARINE... 227 PM CST BROAD SURFACE HIGH PRESSURE COVERS ALL OF LAKE MI THROUGH TONIGHT...HOWEVER THIS FEATURE WILL DRIFT EAST THROUGH TUESDAY BEFORE BECOMING CENTERED OVER NEW ENGLAND TUESDAY AFTERNOON. MEANWHILE A TROUGH OF LOW PRESSURE IS EXPECTED TO DEVELOP OVER NORTHERN LAKE MICHIGAN LATE TONIGHT AND HELP TO BRING A TRAILING FRONTAL BOUNDARY SOUTH ACROSS THE LAKE TUESDAY MORNING. ANOTHER BROAD RIDGE OF HIGH PRESSURE WILL BECOME CENTERED OVER ONTARIO...HOWEVER A SLIGHT INCREASE IN THE PRESSURE GRADIENT WILL INCREASE WINDS A TAD TO 10 TO 20 KT FROM THE NORTHEAST FOR THE NORTHERN PORTIONS OF THE LAKE. FURTHER SOUTH THE WINDS WILL BE FROM THE SOUTHWEST. THIS FRONTAL BOUNDARY WILL SAG FURTHER SOUTH TUESDAY EVENING OF THE LAKE...WITH HIGH PRESSURE STRETCHING BACK ACROSS THE LAKE ONCE AGAIN WEDNESDAY. THEN HIGH PRESSURE WILL COVER THE EASTERN HALF OF THE UNITED STATED WITH A GENERAL TROUGHING STRETCHING FROM JAMES BAY SOUTH THROUGH THE WESTERN GREAT LAKES INTO THE CENTRAL PLAINS. THIS WILL AID IN KEEPING WINDS GENERALLY FROM THE SOUTH TO SOUTHWEST THROUGH THE END OF THE WEEK WITH WINDS GENERALLY AROUND 10 TO 20 KT. BEACHLER && .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/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
320 PM CST MON MAR 3 2014 .DISCUSSION... 319 PM CST THE PRIMARY FORECAST CONCERNS ARE FOR SNOW CHANCES...NAMELY TUE NIGHT AND WED...AND THEN TEMPERATURES OVER MUCH OF THIS WEEK AS IT GETS CHALLENGING WEIGHING FACTORS SUCH AS CLOUD COVER...INCREASING MARCH SUN ANGLE...SNOW COVER...AND FLUCTUATING TEMPERATURES ALOFT. TONIGHT AND TUESDAY MORNING... A STRONG AND BARELY MODIFIED ARCTIC HIGH PRESSURE OF 1035MB IS IN PLACE OVER THE LOCAL AREA GOING INTO THIS EVE. WHILE HEIGHTS ARE SLOWLY RISING ALOFT...THE NEXT IN A SERIES OF SYSTEMS WITHIN FAST PACED WNW FLOW IS APPROACHING THE AREA. THE CENTER OF THE SHORT WAVE IMPULSE ON WATER VAPOR IS SEEN ACROSS NORTH DAKOTA WITH MID CLOUD ALREADY INTO SOUTHWEST WI. THE RAP AND NAM SOLUTIONS OF SIMULATED WATER VAPOR HAVE A GOOD HANDLE ON THIS AND HAVE INCORPORATED THAT APPROACH INTO SKY COVER FORECASTS TONIGHT...WITH CONDITIONS BECOMING CLOUDY BY MID-EVE. THIS WILL MAKE IT TRICKY AS THE SYNOPTIC SCENARIO WOULD FAVOR RAPIDLY FALLING TEMPS THIS EVE BUT THE CLOUDS WILL LIKELY OFFSET THIS SOME. HAVE LEANED THE MILDER ROUTE...ESPECIALLY NORTH OF I-80...WITH A LIMITED DROP-OFF THIS EVE AND THEN TEMPS CLIMBING OVERNIGHT. HAVE THE COOLEST TEMPS FORECAST ACROSS EAST CENTRAL IL INTO NORTHWEST IN WHERE MID CLOUDS WILL TAKE THEIR LONGEST TO THICKEN. THE FORCING FOR PRECIP WILL BE PRIMARILY TO THE EAST AND NORTH OF THE CENTER OF CIRCULATION TO THIS SHORT WAVE...AS IT OFTEN IS WITH THESE PROGRESSIVE ARE LOW AMPLITUDE NORTHWEST FLOW SYSTEMS. THUS AM NOT TOO EXCITED FOR SNOW INTO THE FORECAST AREA...ESPECIALLY GIVEN THE DRY DEEP ATMOSPHERE IN PLACE. SO HAVE LEANED AWAY FROM THE MORE ROBUST 12Z NAM AND CLOSER TO THE RAP AND GLOBAL MODELS...WITH POSSIBLY A DUSTING ALONG AND NORTH OF I-88. TUESDAY AND WEDNESDAY... WHILE THERE MAY BE SOME LIGHT SNOW/FLURRIES EARLY IN NORTHEAST IL...THE DAYTIME TUESDAY LOOKS MAINLY DRY WITH A GAP BETWEEN WAVES LIKELY ALLOWING FOR SOME SUNSHINE. WITH A MUCH WARMER STARTING POINT THAN TODAY...HIGHS LOOK TO REBOUND MORE TOWARD WHERE THEY SHOULD BE GIVEN THE 925MB TEMPS...BUT FAR FROM WHERE THEY SHOULD BE GIVEN THE TIME OF YEAR. HAVE FORECAST HIGHS IN THE LOWER TO MID 20S. THE NEXT SHORT WAVE HAS A BETTER PATH TO FAVOR OUR AREA AND ALSO HAS MORE ELONGATED /LONGER LASTING/ FORCING TIED TO ITS UPPER DYNAMIC SUPPORT AND FRONTOGENESIS. GUIDANCE IS IN FAIR AGREEMENT WITH THE AREA SEEING SNOW...NAMELY OVERNIGHT TUE NIGHT INTO WED MORNING...AND IT MAKES GOOD SENSE GIVEN THE PARAMETERS. SO CONTINUE TO INCREASE POPS. THE SNOW LOOKS TO BE FAIRLY EFFICIENT GIVEN TOP DOWN METHOD AND TEMPERATURE PROFILES...WITH MODEST RATES AT TIMES WHEREVER THAT WEST-TO-EAST BAROCLINIC GRADIENT OF THE SYSTEM PASSES ACROSS. HAVE 1-2.5 INCHES FORECAST FOR A LOT OF THE AREA. HOW MUCH A SECONDARY SHORT WAVE MOVING ACROSS THE MISSOURI RIVER VALLEY GETS INVOLVED WEDNESDAY WILL BE KEY AS WELL...AS THAT COULD BOOST AMOUNTS IN THE SOUTHERN FORECAST AREA. ALSO OF NOTE IS POTENTIAL LAKE EFFECT SETUP ONCE AGAIN INTO WEDNESDAY AFTERNOON AND NIGHT FOR NORTHEAST IL. MILDER TEMPERATURES THAN THIS MORNING WOULD POINT TOWARD NOT AS GOOD OF INSTABILITY...HOWEVER THERE ARE SIGNS OF CONVERGENCE AND BETTER BOUNDARY LAYER RH...AND FOR THAT HAVE CONTINUED POPS ACROSS CHICAGO INTO WEDNESDAY NIGHT. MTF THURSDAY AND BEYOND... LARGE SCALE PATTERN IN THE EXTENDED WILL CONTINUE TO SUPPORT WELL BELOW NORMAL HIGH/LOW TEMPS...WITH LOW CHANCE POSSIBILITIES FOR PRECIP DURING THE PERIOD. GENERAL WEST/NORTHWEST FLOW ALOFT WILL USHER IN SEVERAL WAVES OF ENERGY THROUGH MID WEEK...WITH MODELS IN FAIR AGREEMENT WITH THESE FEATURES AND RESULTANT QPF. ALTHOUGH THE GFS APPEARS TO VARY WITH THE STRENGTH OF A MORE DEFINED SHORTWAVE TROUGH BY LATE WEDNESDAY INTO THURSDAY...AND THEN IS A TAD MORE BULLISH WITH ITS ASSOCIATED PRECIP. NONETHELESS...WHATEVER DEVELOPS SHOULD BE RATHER PROGRESSIVE AND QUICKLY EXIT...AND WITH THERMAL PROFILES SUPPORTIVE OF ALL SNOW DURING THIS PERIOD. PATTERN TRIES TO BECOME MORE ACTIVE LATE IN THE WORK WEEK WHILE SHOWING SIGNS OF SLIGHT WARMING...AS LARGE SCALE PATTERN BECOMES MORE AMPLIFIED OVER THE CENTRAL CONUS WHILE LARGE VORT MAX SHIFTS EAST THROUGH SOUTHERN CANADA. TAIL END OF THIS ENERGY WILL APPROACH THE REGION BY LATE IN THE WORK WEEK...AS WINDS BACK AND WAA OCCURS OUT AHEAD OF IT. THIS SHOULD SUPPORT SOME WARMER TEMPS IN THE MID TO UPPER 30S BY FRIDAY...WITH A MIX OF RAIN AND SNOW THEN POSSIBLE AS ASSOCIATED SURFACE TROUGH/FRONT MOVE OVER THE AREA. ALTHOUGH...THIS WARMING WILL BE BRIEF AS COLDER AIR SHOULD FILTER IN ON THE BACKSIDE OF THIS SYSTEM WITH WELL BELOW NORMAL TEMPS ONCE AGAIN EXPECTED INTO THE WEEKEND. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * LIGHT EASTERLY WIND. * SNOW CHANCES INCREASING TONIGHT INTO EARLY TUESDAY...WITH POSSIBLE MVFR CONDITIONS. RODRIGUEZ //DISCUSSION...UPDATED 18Z... HIGH PRESSURE CONTINUES TO SHIFT EAST ACROSS THE REGION...WHILE LAKE EFFECT SNOW SHOWERS CONTINUE TO DIMINISH. ONLY ANTICIPATE THESE LIGHT SNOW SHOWERS TO PERSIST FOR THE NEXT COUPLE OF HOURS...WHILE MVFR CEILINGS ALSO PERSIST. THEN AS SOON AS THIS DISSIPATES...MID/HIGH LEVEL CLOUD COVER WILL BEGIN TO INCREASE OUT AHEAD OF THE NEXT SYSTEM. LOWERING TRENDS WILL OCCUR TONIGHT INTO TUESDAY MORNING...WHILE SNOW CHANCES ALSO INCREASE. WENT A TAD MORE PESSIMISTIC WITH THIS SNOW AND VIS TONIGHT...BUT NOT AS AGGRESSIVE AS CONDITIONS COULD POSSIBLY BE DUE TO REMAINING UNCERTAINTY. WILL NEED TO MONITOR POSSIBLE HEAVIER SNOW AND LOWER VIS FOR TIME LATE TONIGHT/EARLY TUESDAY MORNING. LIGHT NORTHEAST WINDS WILL VEER TO THE EAST AND SOUTHEAST THIS AFTERNOON AND THIS EVENING...BEFORE BECOMING MORE SOUTHERLY OVERNIGHT INTO TUESDAY. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 20Z... * MEDIUM HIGH CONFIDENCE IN WIND TRENDS. * MEDIUM CONFIDENCE IN LIGHT SNOW TONIGHT. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT THROUGH THURSDAY...MAINLY VFR WITH PERIODIC CHANCES OF LIGHT SNOW AND MVFR/IFR...ESPECIALLY TUESDAY NIGHT AND WEDNESDAY. FRIDAY AND SATURDAY...CHANCE OF LIGHT RAIN OR SNOW FRIDAY AND A CHANCE OF SNOW SATURDAY. PERIODS OF MVFR/IFR POSSIBLE. MDB && .MARINE... 227 PM CST BROAD SURFACE HIGH PRESSURE COVERS ALL OF LAKE MI THROUGH TONIGHT...HOWEVER THIS FEATURE WILL DRIFT EAST THROUGH TUESDAY BEFORE BECOMING CENTERED OVER NEW ENGLAND TUESDAY AFTERNOON. MEANWHILE A TROUGH OF LOW PRESSURE IS EXPECTED TO DEVELOP OVER NORTHERN LAKE MICHIGAN LATE TONIGHT AND HELP TO BRING A TRAILING FRONTAL BOUNDARY SOUTH ACROSS THE LAKE TUESDAY MORNING. ANOTHER BROAD RIDGE OF HIGH PRESSURE WILL BECOME CENTERED OVER ONTARIO...HOWEVER A SLIGHT INCREASE IN THE PRESSURE GRADIENT WILL INCREASE WINDS A TAD TO 10 TO 20 KT FROM THE NORTHEAST FOR THE NORTHERN PORTIONS OF THE LAKE. FURTHER SOUTH THE WINDS WILL BE FROM THE SOUTHWEST. THIS FRONTAL BOUNDARY WILL SAG FURTHER SOUTH TUESDAY EVENING OF THE LAKE...WITH HIGH PRESSURE STRETCHING BACK ACROSS THE LAKE ONCE AGAIN WEDNESDAY. THEN HIGH PRESSURE WILL COVER THE EASTERN HALF OF THE UNITED STATED WITH A GENERAL TROUGHING STRETCHING FROM JAMES BAY SOUTH THROUGH THE WESTERN GREAT LAKES INTO THE CENTRAL PLAINS. THIS WILL AID IN KEEPING WINDS GENERALLY FROM THE SOUTH TO SOUTHWEST THROUGH THE END OF THE WEEK WITH WINDS GENERALLY AROUND 10 TO 20 KT. BEACHLER && .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/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS GOODLAND KS
238 PM MST MON MAR 3 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 1234 PM MST MON MAR 3 2014 A RETURN TO MUCH WARMER TEMPS THIS WEEK. LARGE-SCALE PATTERN TO BEGIN THE WEEK IS FAIRLY QUIET WITH A ZONAL TO SUBTLE LONGWAVE RIDGE OVER THE WESTERN HALF OF THE CONUS TO A LONGWAVE TROUGH IN THE EAST...PLACING OUR REGION IN A WEST-NORTHWEST FLOW AT THE MID AND UPPER LEVELS. BELOW THIS...WILL SEE WARM AIR ADVECTION OUT OF THE SOUTH/SOUTHWEST THROUGH THE DAY TODAY BEFORE BACKING TO THE WEST TOMORROW. LATE TOMORROW A COLD FRONT WILL MOVE THROUGH THE REGION. TODAY...MORNING BEGAN QUITE BREEZY...WITH GUSTS APPROACHING 30 MPH AT A FEW SITES. CLOUDS MOVING IN FROM THE NORTHWEST THIS MORNING WILL MOVE ACROSS THE REGION THIS AFTERNOON AS THEY DISSIPATE. MODEL OUTPUT FROM GFS AND NAM ESPECIALLY GENERALLY NOT USEFUL FOR NEAR SURFACE PARAMETERS DUE TO SNOW DEPTH BEING INITIALIZED MUCH TOO DEEP ACROSS NORTHEAST COLORADO AND WESTERN KANSAS. RAP DOES NOT SEEM TO BE SUFFERING FROM THIS...SO LEANED TOWARDS RAP/ECMWF FOR TEMPS TODAY INTO TONIGHT. WHERE THERE IS SNOW AND SOME CLOUD COVER ACROSS GREELEY AND WICHITA COUNTIES TEMPS HAVE BEEN MUCH COLDER...BUT ELSEWHERE A PLEASANT AND WARMER DAY AFTER A BITTER COLD WEEKEND. TONIGHT...CLEARING SKIES AND 850MB TEMPS CONTINUING TO RISE WILL MAKE FOR NEAR-NORMAL TEMPS. WINDS WILL BE LIGHT OUT OF THE SOUTH...LIGHT ENOUGH TO ALLOW PATCHY FOG TO FORM IN A FEW SPOTS. HAVE ADDED PATCHY FOG FOR SOUTHWEST NEBRASKA AND IN PARTS OF ADJACENT COLORADO/KANSAS COUNTIES GENERALLY BASED OFF OF THE RAP MODEL SOUNDINGS AND TRENDS. THOUGH BELIEVE SOME OF THE FOG DEVELOPMENT IN SREF/NAM ARE DUE TO SNOW FIELD...WITH RAP ALSO HINTING AT A GOOD LOW-LEVEL MOISTURE LAYER FEEL COMFORTABLE WITH AT LEAST SOME PATCHY FOG. MUCH WILL BE DEPENDENT ON WINDS...AND IF WINDS REMAIN UP AROUND 5-10 MPH OVERNIGHT MIGHT NOT SEE ANY FOG DEVELOPMENT WHATSOEVER. WEDNESDAY...SUNNY AND WARM FOR THE MOST PART. HIGHS APPROACHING 60 IN MOST SPOTS AS 850MB TEMPS REACH AROUND 10C...WITH ECMWF AND GEM GOING EVEN WARMER. INCREASING CLOUDS THROUGHOUT THE AFTERNOON WITH WINDS BECOMING OUT OF THE NORTHWEST AS A WEAK FRONT MOVES ACROSS THE REGION. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 237 PM MST MON MAR 3 2014 TUESDAY NIGHT-WEDNESDAY MORNING...QUICK MOVING POSITIVELY TILTED SHORTWAVE TROUGH MOVES ACROSS THE REGION TUESDAY NIGHT-WEDNESDAY MORNING. ASSOCIATED COLD FRONT MOVES ACROSS THE REGION TUESDAY EVENING. QUICKER END OF GUIDANCE ACTUALLY BRINGS FRONT IN A LITTLE EARLIER (POSSIBLY TUESDAY AFTERNOON)...THOUGH THIS WILL HAVE LITTLE IMPACT ON SENSIBLE WEATHER DURING THESE PERIODS. CAA IS FAIRLY WEAK BEHIND THIS FRONT AND BEST COOLING MODELS ARE SHOWING IS WITH PRECIP BAND (LIKELY DUE TO EVAPORATIVE PROCESSES). CURRENT MODELS SEEM TO BE IN GENERAL AGREEMENT ON COUPLED JET STRUCTURE (AND ASSOCIATED LARGE SCALE ASCENT) MOVING OVER OUR CWA LATE TUESDAY NIGHT...WITH SUBSIDENCE QUICKLY MOVING IN FROM THE WEST WED MORNING. MODEL QPF FIELDS GENERALLY MATCH ON TIMING ON AREA OF PRECIP MOVING OVER OUR CWA DURING THIS PERIOD...SO I TRENDED POPS UP DURING THE LATE NIGHT PERIOD...AND QUICKLY ENDED POPS DURING THE WED MORNING PERIOD. REGARDING PRECIP TYPE...VERY LITTLE E-SE MOISTURE RETURN AHEAD OF MAIN SHORTWAVE TROUGH IN THE LOW LEVELS...SO IM NOT SEEING A LOT OF OPPORTUNITY FOR DRIZZLE/FREEZING DRIZZLE. A FEW SOUNDINGS TRY TO SHOW LOW LEVEL SATURATION IN OUR SOUTHEAST...HOWEVER WITH VERY BRIEF WINDOW BEFORE NW FLOW OVERTAKES REGION OR MAIN AREA OF PRECIP MOVES IN IM NOT SEEING THIS BEING WORTH A MENTION. WHILE INITIALLY THERE IS A WARM LAYER...SATURATION ABOVE THIS LAYER WILL OCCUR WHEN MAIN PRECIP AREA MOVES IN AND TEMPERATURE (AND BY THAT POINT WEAK CAA/EVAPORATIVE PROCESSES HAVE REMOVED THIS WARM LAYER FROM THE EQUATION)...SO SLEET IS UNLIKELY. PROFILES GENERALLY SHOW CLEAN RAIN-SNOW TRANSITION WITH MINIMAL CAA IN THE LOW LEVELS...SO I WENT AHEAD AND REMOVED FZDZ/FZRA AND LEFT TYPE AS RAIN/SNOW. DUE TO RELIANCE ON EVAPORATIVE PROCESSES FOR RAIN/SNOW TRANSITION AMOUNTS ARE TRICKY. CURRENT GUIDANCE AND FORECAST TIMING GENERALLY SHOWS SNOW AMOUNTS AROUND ONE INCH OR LESS POSSIBLE (FAIRLY WET AND SLUSHY). WEDNESDAY AFTERNOON-THURSDAY NIGHT...WARM FRONT MOVES THROUGH REGION AND SHORTWAVE RIDGE BUILDS ALOFT ALLOWING FOR QUICK RETURN OF MILD TEMPS/DRY CONDITIONS. TEMPERATURES WARM UP CONSIDERABLY THURSDAY WITH MEX/ECE SHOWING HIGHS AROUND 70F. H85 TEMPS GENERALLY SUPPORTIVE OF MID 60S-LOW 70S (DEPENDING ON WHICH END OF GUIDANCE YOU CHOOSE) USING STANDARD BIAS. I TRENDED TEMPS UP ACROSS THE CWA TO UPPER 60S THURSDAY...AND COULD STILL BE A LITTLE LOW COMPARED TO WARMER END OF GUIDANCE. FRIDAY-FRIDAY NIGHT...NEXT QUICK MOVING SHORTWAVE TROUGH MOVES THROUGH THE PLAINS DURING THESE PERIODS BRINGING PRECIP CHANCES AND SEASONABLY COOL TEMPS BACK TO OUR CWA. STILL A LOT OF SPREAD IN EVOLUTION OF THIS PATTERN...HOWEVER CARRYING SLIGHT CHANCE/CHANCE POPS SEEMS REASONABLE BASED ON OVERALL TRENDS/CONSENSUS. SATURDAY-SUNDAY...WHILE THERE IS RUN-RUN MODEL SPREAD DURING THESE PERIODS...GENERAL CONSENSUS SHOWS SHORTWAVE RIDGING (OF SOME FLAVOR) AND DRY CONDITIONS AND WARMING TEMPS TO ABOVE NORMAL VALUES NEXT WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1109 AM MST MON MAR 3 2014 VFR TO MVFR CONDITIONS EXPECTED THROUGH THE TAG PERIOD AT GLD AND MCK. WINDS ARE A BIT GUSTY EARLY TODAY GUSTING TO OVER 30KTS AT GLD...BUT AM EXPECTING THESE WINDS TO GRADUALLY DECREASE THIS AFTERNOON. SCATTERED MID AND HIGH CLOUDS THIS AFTERNOON SHOULD DISSIPATE LATE TODAY. PATCHY FOG DEVELOPMENT IS POSSIBLE AT MCK TONIGHT LEADING TO MVFR OR WORSE CONDITIONS. BELIEVE MOISTURE FIELD OF NAM/SREF TO BE OVERDOING THE NEAR-SURFACE CONDITIONS...BUT IF WINDS CAN GO CALM FOR A FEW HOURS BELIEVE AT LEAST SOME PATCHY MVFR FOG WILL DEVELOP...WITH A POSSIBILITY OF IFR VIS FOR A FEW HOURS OVERNIGHT. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...JJM LONG TERM...DR AVIATION...JJM
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
156 PM CST Mon Mar 3 2014 ...Updated for the long term forecast... .SHORT TERM...(This evening through Tuesday) ISSUED AT 142 PM CST MON MAR 3 2014 Tonight: Some mid to high level clouds will continue tonight in association with a jet streak passing off to the southeast. Southerly winds will become SSW/SW after midnight. The downslope winds should lead to higher minimums for much of the region, except over deeper snowpack. Calling for mid to upper 20sF by Elkhart to upper single digits to lower teens across the deeper snowpack (generally along and east of Highway 183). Tomorrow: The HRRR is suggesting fog formation tonight, but this is different than what the WRF is suggesting. Think the model fields might be too heavily influenced by the model snowpack. If fog does develop, it will be patchy. Lee troughing will continue tomorrow. Downslope, compressional warming is expected ahead of a frontal boundary. This front will traverse the region after my short-term period ends. A fairly impressive gradient of maximum temperatures is expected across the forecast area of responsibility. Low 60sF will be possible across the western zones, where the warmest 850 hPa temperatures are expected along with the strongest downslope wind component. Have undercut temperature guidance farther east across the heavier snowpack areas, where low 40sF are possible for highs. Any precipitation will remain outside of my period. .LONG TERM...(Tuesday night through Monday) ISSUED AT 148 PM CST MON MAR 3 2014 This extended period will be dominated by a two different upper level troughs passing through, one on Tuesday night and Wednesday, and the other one on Friday night and Saturday. In the nearer term, Tuesday night should be cold with lows in the mid 20s in the Hays and LaCrosse areas, ranging to the mid 30s down down in our southwest corner near Elkhart. I think the front will be in the I-70 corridor about midnight, with some overrunning precipitation beginning by midnight, in the form of snow and/or sleet. Forecast sounding from nearly every model shows a warm tongue aloft, for the early part of the event. The front will spill southward through Southwestern and South Central Kansas on Wednesday, and most of the rest of our forecast area will see some snow/sleet early Wednesday, changing over to rain by late morning. The dynamics will be stronger to our north, so 20 to 30 percent precipitation chances will suffice for us. Only light QPF amounts are expected, generally less than 0.03 inch liquid, and perhaps up to a half inch of snow in any particular location. Wednesday`s high temperatures Will range from 39F in Hays to 52F in Johnson City. Wednesday night through Friday will see some warming, with the coolest highs across any accumulation of snow. Wednesday night minimum temperatures will still be similar to mins Wednesday morning, in the mid 20s to lower 30s. There will be a quick warm up Thursday with southwest surface winds. Maximum temperatures in the southwest corner near Ulysses and Elkhart will rise into the lower to middle 60s, while the east sections from Ellis to Comanche Counties will only top out in the lower to middle 50s. There will be some advance clouds moving in Friday, which will knock down maximum temperatures Friday into the upper 40s north of I-70, ranging to near 60F down south along the Oklahoma border. As an upper wave moves into the plains Friday night, a cold front will dive southeast from Wyoming. This will bring another round of snow or rain to Southwest Kansas Friday Night and Saturday. I did lower some of the 50% Pops from the AllBlend model to 30 and 40 percent, to better match our neighbor`s grids. Friday night will see a cool down in low temperatures, dropping to the mid 20s to lower 30s. Saturday should be significantly colder, with the clouds and precipitation around. Highs should only reach the middle 40s to near 50F on Saturday. Sunday looks mostly sunny and considerably warmer, with max temps in the upper 50s near Larned and the middle 60s in the Syracuse area. Sunday will be sunny and even warmer with max temps in the middle 60s across the forecast area. Minimum temperatures both Saturday and Sunday mornings will average in the 25F to 30F degree range. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) ISSUED AT 1100 AM CST MON MAR 3 2014 VFR conditions through TAF pd. Some mid to high level clouds, but no major flight category reductions. Southerly winds 8-12 kt today becoming southwesterly 6-11 kt overnight. && .PRELIMINARY POINT TEMPS/POPS... DDC 11 45 27 44 / 0 0 10 30 GCK 13 52 28 46 / 0 0 10 30 EHA 23 60 33 52 / 0 0 10 20 LBL 15 52 30 50 / 0 0 10 20 HYS 10 45 25 39 / 0 0 20 40 P28 11 40 25 42 / 0 0 10 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sugden LONG TERM...Burke AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
142 PM CST Mon Mar 3 2014 ...Update to short term... .SHORT TERM...(This evening through Tuesday) ISSUED AT 142 PM CST MON MAR 3 2014 Tonight: Some mid to high level clouds will continue tonight in association with a jet streak passing off to the southeast. Southerly winds will become SSW/SW after midnight. The downslope winds should lead to higher minimums for much of the region, except over deeper snowpack. Calling for mid to upper 20sF by Elkhart to upper single digits to lower teens across the deeper snowpack (generally along and east of Highway 183). Tomorrow: The HRRR is suggesting fog formation tonight, but this is different than what the WRF is suggesting. Think the model fields might be too heavily influenced by the model snowpack. If fog does develop, it will be patchy. Lee troughing will continue tomorrow. Downslope, compressional warming is expected ahead of a frontal boundary. This front will traverse the region after my short-term period ends. A fairly impressive gradient of maximum temperatures is expected across the forecast area of responsibility. Low 60sF will be possible across the western zones, where the warmest 850 hPa temperatures are expected along with the strongest downslope wind component. Have undercut temperature guidance farther east across the heavier snowpack areas, where low 40sF are possible for highs. Any precipitation will remain outside of my period. .LONG TERM...(Tuesday through Sunday) ISSUED AT 227 AM CST MON MAR 3 2014 A trough of low pressure will remain nearly stationary along the lee of the Rockies on Tuesday as a cold front moves south into Nebraska by late day. Ahead of this cold front an area of warm 925mb to 850mb air is forecast to cross western Kansas during the afternoon. Using the 00z Wednesday 850mb temperatures as a guide for highs the potential exists for temperatures climb back into the 60s given full sun. At this time however will only trend towards these warmer temperatures only across west central and portions of far western Kansas given the potential for clouds along with some linger snow cover. Confidence is not high on where the snow cover will be on Tuesday but using the Dual Pol Storm Total Accum estimates as a guide will favor keeping some lingering snow cover southeast of a Liberal to Dodge City to Larned line. In this area trended afternoon temperatures towards the cooler MET guidance which suggested highs only in the lower 40s. Both the NAM and GFS agree in moving a cold front across southwest Kansas Tuesday night with increasing low and mid level moisture developing in the wake of this cold front late Tuesday night/early Wednesday. Despite the agreement in frontal passage the NAM and GFS disagree on the depth and how quickly the lower levels saturate. NAM was more aggressive and as a result attempts to generate some light precipitation between 06z and 12z across most of southwest Kansas as an upper level trough crosses the Central High Plains. GFS was not as aggressive and therefore kept the precipitation chances in west central and portions of north central Kansas where the better mid level moisture and forcing will be present prior to 12z Wednesday. Given the uncertainty on how the lower levels will saturate late Tuesday night will currently favor the GFS and keep small precipitation chances mainly across west central and north central Kansas based on where the better mid level forcing will be located ahead of this mid week upper level system. On Wednesday the upper level trough will cross western Kansas early in the day with subsidence and drying forecast during the afternoon behind this upper level system. Based on the 00z NAM and 00z GFS timing of this upper level trough will keep a chance of precipitation going early Wednesday but taper this precipitation off from west to east, mainly after 18z. Given the net 24hour change in 950 to 850mb temperatures of roughly 3 to 7C the previous forecast still look on track with Highs on Wednesday mainly in the 40s. Lower 50s still look likely across portions of southwest Kansas. May even be a little warmer than this across far western Kansas if skies clear sooner. CRExtendFcst_Init still looks on track with Highs rebounding back into the upper 50s to mid 60s on Thursday given that 850mb temperatures warm from the single digits into the teens. Another cold front crossing into western Kansas on Friday will put an end to this warming trend with cooler temperatures returning by Saturday. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) ISSUED AT 1100 AM CST MON MAR 3 2014 VFR conditions through TAF pd. Some mid to high level clouds, but no major flight category reductions. Southerly winds 8-12 kt today becoming southwesterly 6-11 kt overnight. && .PRELIMINARY POINT TEMPS/POPS... DDC 11 45 27 44 / 0 0 10 30 GCK 13 52 28 46 / 0 0 10 30 EHA 23 60 33 52 / 0 0 10 20 LBL 15 52 30 50 / 0 0 10 20 HYS 10 45 25 39 / 0 0 20 40 P28 11 40 25 42 / 0 0 10 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sugden LONG TERM...Burgert AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1234 PM MST MON MAR 3 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 1234 PM MST MON MAR 3 2014 A RETURN TO MUCH WARMER TEMPS THIS WEEK. LARGE-SCALE PATTERN TO BEGIN THE WEEK IS FAIRLY QUIET WITH A ZONAL TO SUBTLE LONGWAVE RIDGE OVER THE WESTERN HALF OF THE CONUS TO A LONGWAVE TROUGH IN THE EAST...PLACING OUR REGION IN A WEST-NORTHWEST FLOW AT THE MID AND UPPER LEVELS. BELOW THIS...WILL SEE WARM AIR ADVECTION OUT OF THE SOUTH/SOUTHWEST THROUGH THE DAY TODAY BEFORE BACKING TO THE WEST TOMORROW. LATE TOMORROW A COLD FRONT WILL MOVE THROUGH THE REGION. TODAY...MORNING BEGAN QUITE BREEZY...WITH GUSTS APPROACHING 30 MPH AT A FEW SITES. CLOUDS MOVING IN FROM THE NORTHWEST THIS MORNING WILL MOVE ACROSS THE REGION THIS AFTERNOON AS THEY DISSIPATE. MODEL OUTPUT FROM GFS AND NAM ESPECIALLY GENERALLY NOT USEFUL FOR NEAR-SURFACE PARAMETERS DUE TO SNOW DEPTH BEING INITIALIZED MUCH TOO DEEP ACROSS NORTHEAST COLORADO AND WESTERN KANSAS. RAP DOES NOT SEEM TO BE SUFFERING FROM THIS...SO LEANED TOWARDS RAP/ECMWF FOR TEMPS TODAY INTO TONIGHT. WHERE THERE IS SNOW AND SOME CLOUD COVER ACROSS GREELEY AND WICHITA COUNTIES TEMPS HAVE BEEN MUCH COLDER...BUT ELSEWHERE A PLEASANT AND WARMER DAY AFTER A BITTER COLD WEEKEND. TONIGHT...CLEARING SKIES AND 850MB TEMPS CONTINUING TO RISE WILL MAKE FOR NEAR-NORMAL TEMPS. WINDS WILL BE LIGHT OUT OF THE SOUTH...LIGHT ENOUGH TO ALLOW PATCHY FOG TO FORM IN A FEW SPOTS. HAVE ADDED PATCHY FOG FOR SOUTHWEST NEBRASKA AND IN PARTS OF ADJACENT COLORADO/KANSAS COUNTIES GENERALLY BASED OFF OF THE RAP MODEL SOUNDINGS AND TRENDS. THOUGH BELIEVE SOME OF THE FOG DEVELOPMENT IN SREF/NAM ARE DUE TO SNOW FIELD...WITH RAP ALSO HINTING AT A GOOD LOW-LEVEL MOISTURE LAYER FEEL COMFORTABLE WITH AT LEAST SOME PATCHY FOG. MUCH WILL BE DEPENDENT ON WINDS...AND IF WINDS REMAIN UP AROUND 5-10 MPH OVERNIGHT MIGHT NOT SEE ANY FOG DEVELOPMENT WHATSOEVER. WEDNESDAY...SUNNY AND WARM FOR THE MOST PART. HIGHS APPROACHING 60 IN MOST SPOTS AS 850MB TEMPS REACH AROUND 10C...WITH ECMWF AND GEM GOING EVEN WARMER. INCREASING CLOUDS THROUGHOUT THE AFTERNOON WITH WINDS BECOMING OUT OF THE NORTHWEST AS A WEAK FRONT MOVES ACROSS THE REGION. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 318 AM MST MON MAR 3 2014 THE PERIOD WILL START OFF DRY WITH A SHORT WAVE RIDGE OVER THE AREA THURSDAY. FRIDAY AN UPPER LEVEL LONG WAVE TROUGH APPROACHES FROM THE WEST. MODELS CONTINUE TO TREND MORE TOWARD THE LOW WAVE TROUGH DEEPENING TO THE WEST...PLACING LARGE SCALE LIFT EAST OVER THE TRI-STATE AREA. AS FRIDAY PROGRESSES THE TROUGH WILL DRIFT SOUTH...WHICH WILL ALLOW THE LARGE SCALE LIFT TO REMAIN OVER THE AREA. BY SATURDAY MORNING THE TROUGH AXIS WILL MOVE SOUTH ACROSS THE AREA BRINGING THE PRECIP. TO AN END. THIS PATTERN LOOKS MORE FAVORABLE FOR PRECIP. FOR THE AREA THAN WHEN MODELS HAD THE LONG WAVE TROUGH MOVING ACROSS THE AREA. AN UPPER LEVEL RIDGE WILL MOVE ACROSS THE AREA SATURDAY AND SUNDAY BEHIND THE DEPARTING TROUGH. TEMPERATURES FOR THE PERIOD WILL REMAIN ABOVE NORMAL. THURSDAY WILL BE THE WARMEST DAY WITH HIGHS IN THE LOW TO MID 60S AND LOWS IN THE LOW TO MID 30S. A COLD FRONT WILL MOVE THROUGH THE AREA FRIDAY USHERING IN NEAR NORMAL TEMPERATURES BEHIND IT. THE SEASONAL AIR MASS REMAINS OVER THE AREA UNTIL SUNDAY WHEN A WARM FRONT MOVES THROUGH BRINGING WELL ABOVE NORMAL TEMPERATURES BACK TO THE AREA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1109 AM MST MON MAR 3 2014 VFR TO MVFR CONDITIONS EXPECTED THROUGH THE TAG PERIOD AT GLD AND MCK. WINDS ARE A BIT GUSTY EARLY TODAY GUSTING TO OVER 30KTS AT GLD...BUT AM EXPECTING THESE WINDS TO GRADUALLY DECREASE THIS AFTERNOON. SCATTERED MID AND HIGH CLOUDS THIS AFTERNOON SHOULD DISSIPATE LATE TODAY. PATCHY FOG DEVELOPMENT IS POSSIBLE AT MCK TONIGHT LEADING TO MVFR OR WORSE CONDITIONS. BELIEVE MOISTURE FIELD OF NAM/SREF TO BE OVERDOING THE NEAR-SURFACE CONDITIONS...BUT IF WINDS CAN GO CALM FOR A FEW HOURS BELIEVE AT LEAST SOME PATCHY MVFR FOG WILL DEVELOP...WITH A POSSIBILITY OF IFR VIS FOR A FEW HOURS OVERNIGHT. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...JJM LONG TERM...JTL AVIATION...JJM
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
209 PM EST MON MAR 3 2014 .UPDATE... ISSUED AT 145 PM EST MON MAR 3 2014 TEMPS AND POPS WERE FINE TUNED BASED ON RECENT OBSERVATIONS. THE WINTER STORM IS NOW WINDING DOWN ACROSS THE REGION AND ATTM...IT APPEARS THAT WE WILL CANCEL AND OR ALLOW THE REMAINING COUNTIES TO EXPIRE AT 4 PM AND THEN ISSUE AN SPS FOR THOSE LOCATIONS TO HIGHLIGHT CONTINUED SLICK ROADS TONIGHT. UPDATE ISSUED AT 1215 PM EST MON MAR 3 2014 ONE UPDATE HAS BEEN ISSUED THIS MORNING TO FINE TUNE TEMPS AND POPS SO AS TO BETTER TIME THE DEFORMATION BAND SOUTHEAST ACROSS THE CWA. SNOWFALL RATES IN THIS BAND HAVE BEEN ABOUT ONE INCH PER HOUR WITH UP TO 2 INCHES HAVING FALLEN IN THIS BAND IN SOME AREAS NEAR AND TO THE NORTH OF THE MOUNTAIN PARKWAY. ATTM...THE NORTHWEST COUNTIES LOOK ON TARGET TO CANCEL THE WINTER STORM WARNING AS THE SNOW HAS ALREADY ENDED...BUT DIFFICULT TRAVEL REMAINS...ESPECIALLY ON SECONDARY AND UNTREATED ROADS. AN SPS WILL LIKELY BE ISSUED AS SEGMENTS ARE DROPPED FROM THE WINTER STORM WARNING. UPDATE ISSUED AT 745 AM EST MON MAR 3 2014 WENT AHEAD AND UPDATED THE TEXT PRODUCTS TO REMOVE THE FLOOD WATCH IN THE SOUTH AND ALSO DROP THE HEAVY SNOW AND THUNDER MENTION. ALSO FINE TUNED TEMPERATURES AND DEWPOINTS THROUGH THE NEXT FEW HOURS FOR OBS AND TRENDS. THESE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. IN ADDITION...THE ZONES AND HWO WERE UPDATED. UPDATE ISSUED AT 615 AM EST MON MAR 3 2014 THE BACK EDGE OF THE HEAVIER PCPN IS NOW MOVING THROUGH THE SOUTHERN PART OF THE CWA. WHEN THIS EXITS WE WILL LOSE MUCH OF THE CONVECTIVE PCPN AND THREAT OF THUNDER. LIGHTER SNOWS WILL CONTINUE OFF AND ON FOR MUCH OF THE DAY UNTIL THE DEFORMATION ZONES PASSES THROUGH EAST KENTUCKY LATER THIS AFTERNOON. HAVE UPDATED THE GRIDS TO REFLECT THE LATEST RADAR TRENDS AND GUIDANCE FROM THE HRRR AND 06Z NAM12. ALSO FINE TUNED THE T AND TD GRIDS FOR THE NEXT SEVERAL HOURS PER THE LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. A MORE COMPLETE UPDATE TO THE TEXT PRODUCTS WILL TAKE PLACE WITH THE EXPIRATION OF THE FLOOD WATCH AT 7 AM. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 421 AM EST MON MAR 3 2014 A SURFACE HIGH PRESSURE RIDGE OVER THE REGION WILL BE BREAKING DOWN AT THE START OF THE PERIOD...BUT DRY AIR WILL STILL BE IN PLACE AND THEIR WILL BE NO SIGNIFICANT UPPER LEVEL FEATURES THROUGH AT LEAST WEDNESDAY...SO THE WEATHER WILL REMAIN UNEVENTFUL. ON WEDNESDAY NIGHT...AN AMPLIFYING TROUGH WILL BE DROPPING SE TOWARD THE LOWER MISSISSIPPI VALLEY. MODELS ARE NOW LESS INCLINED TO CLOSE OFF A MID/UPPER LEVEL LOW WITH THIS SYSTEM...AND AS A RESULT THEY ARE MORE PROGRESSIVE WITH IT. SURFACE DEVELOPMENT IS STILL INDICATED OVER THE GULF...BUT IT TRACKS FURTHER EAST THAN IN RUNS OF RECENT DAYS. AS A RESULT...IT IS LOOKING LESS LIKELY THAT WE WILL SEE DIRECT EFFECTS FROM THE CYCLOGENESIS. HOWEVER...THE MID/UPPER LEVEL TROUGH COULD BRING SOME LIGHT RAIN ON THURSDAY OR THURSDAY EVENING AS IT PASSES. A TRANSITORY RIDGE AT THE SURFACE AND ALOFT WILL THEN MOVE THROUGH ON FRIDAY AND FRIDAY NIGHT...WITHOUT ANY COOLING IN THE WAKE OF THE DEPARTING SYSTEM. ANOTHER LARGE SCALE MID/UPPER LEVEL TROUGH AND ITS ASSOCIATED COLD FRONT ARE EXPECTED TO HEAD IN FROM THE NW DURING THE WEEKEND. GFS AND ECMWF AGREE ON THE BIG PICTURE FOR THIS...BUT SHOW SOME TIMING DIFFERENCES. TAKING BOTH INTO CONSIDERATION...THE MOST LIKELY TIME FOR PRECIP WILL BE SATURDAY NIGHT. WITH THE UNCERTAINTY...HAVE KEPT POPS IN THE CHANCE CATEGORY EVEN FOR SATURDAY NIGHT...WITH A BUFFER OF LOWER POPS ON BOTH SIDES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1225 PM EST MON MAR 3 2014 LIFR AND IFR CONDITIONS WILL BE THE RULE THIS MORNING ACROSS THE AREA AS THE LAST ROUND OF LIGHT TO MODERATE SNOW MOVES THROUGH EAST KENTUCKY. FAR SOUTHEAST PARTS OF THE STATE ARE NOW ALL SNOW. CONDITIONS WILL BEGIN TO IMPROVE FROM WEST TO EAST TOWARDS MID AFTERNOON. VFR WX SHOULD TAKE OVER THE REGION LATER THIS AFTERNOON AND LAST INTO THE NIGHT. WINDS WILL BE NORTHEAST AROUND 10 KTS WITH GUSTS TO 20 KTS POSSIBLE...BEFORE SETTLING TO LESS THAN 10 KTS AND BECOME MORE EASTERLY LATER THIS AFTERNOON AND INTO THE NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR KYZ058>060-068-069-104-106>109-111-112-114. WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR KYZ079-080- 083>088-110-113-115>120. && $$ UPDATE...JP SHORT TERM...GREIF/JMW LONG TERM...HAL AVIATION...DUSTY
AREA FORECAST DISCUSSION
NWS JACKSON KY
1225 PM EST MON MAR 3 2014 .UPDATE... ISSUED AT 1215 PM EST MON MAR 3 2014 ONE UPDATE HAS BEEN ISSUED THIS MORNING TO FINE TUNE TEMPS AND POPS SO AS TO BETTER TIME THE DEFORMATION BAND SOUTHEAST ACROSS THE CWA. SNOWFALL RATES IN THIS BAND HAVE BEEN ABOUT ONE INCH PER HOUR WITH UP TO 2 INCHES HAVING FALLEN IN THIS BAND IN SOME AREAS NEAR AND TO THE NORTH OF THE MOUNTAIN PARKWAY. ATTM...THE NORTHWEST COUNTIES LOOK ON TARGET TO CANCEL THE WINTER STORM WARNING AS THE SNOW HAS ALREADY ENDED...BUT DIFFICULT TRAVEL REMAINS...ESPECIALLY ON SECONDARY AND UNTREATED ROADS. AN SPS WILL LIKELY BE ISSUED AS SEGMENTS ARE DROPPED FROM THE WINTER STORM WARNING. UPDATE ISSUED AT 745 AM EST MON MAR 3 2014 WENT AHEAD AND UPDATED THE TEXT PRODUCTS TO REMOVE THE FLOOD WATCH IN THE SOUTH AND ALSO DROP THE HEAVY SNOW AND THUNDER MENTION. ALSO FINE TUNED TEMPERATURES AND DEWPOINTS THROUGH THE NEXT FEW HOURS FOR OBS AND TRENDS. THESE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. IN ADDITION...THE ZONES AND HWO WERE UPDATED. UPDATE ISSUED AT 615 AM EST MON MAR 3 2014 THE BACK EDGE OF THE HEAVIER PCPN IS NOW MOVING THROUGH THE SOUTHERN PART OF THE CWA. WHEN THIS EXITS WE WILL LOSE MUCH OF THE CONVECTIVE PCPN AND THREAT OF THUNDER. LIGHTER SNOWS WILL CONTINUE OFF AND ON FOR MUCH OF THE DAY UNTIL THE DEFORMATION ZONES PASSES THROUGH EAST KENTUCKY LATER THIS AFTERNOON. HAVE UPDATED THE GRIDS TO REFLECT THE LATEST RADAR TRENDS AND GUIDANCE FROM THE HRRR AND 06Z NAM12. ALSO FINE TUNED THE T AND TD GRIDS FOR THE NEXT SEVERAL HOURS PER THE LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. A MORE COMPLETE UPDATE TO THE TEXT PRODUCTS WILL TAKE PLACE WITH THE EXPIRATION OF THE FLOOD WATCH AT 7 AM. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 315 AM EST MON MAR 3 2014 ...THE REST OF THE NIGHT THROUGH TODAY... ...MAJOR WINTER STORM CONTINUES THROUGH THE MORNING... 07Z SFC ANALYSIS...AND RADAR/SATELLITE IMAGERY...SHOWS A WELL DEFINED LOW PRESSURE AREA ROLLING EAST NORTHEAST THROUGH THE TENNESSEE VALLEY. THIS IS RUNNING ALONG AN ARCTIC BOUNDARY THAT CONTINUES TO SAG SOUTH THROUGH THE THIN REMAINDER OF THE STATE NOT IN THE DEEP FREEZE. THE WARM NOSE WITH THIS SYSTEM REMAINS AN ISSUE FOR MUCH OF THE AREA ALONG AND SOUTH OF THE MOUNTAIN PARKWAY...PER OBS AND THE TRANSITION SHOWING UP IN THE DOPPLER CC LOOP. A PERIOD OF FREEZING RAIN HAS BEEN DEPOSITING GENERALLY BETWEEN A TENTH TO A QUARTER OF AN INCH OF ICE BEFORE THE SLEET STARTS TO REALLY ACCUMULATE FOR MOST PLACES. REPORTS OF HALF INCH SLEET TOTALS ARE STARTING TO COME IN FROM PLACES NORTH AND WEST OF JKL. THE OFFICE IS PUSHING THAT TOTAL...AS WELL...THOUGH SOME SNOW HAS BEEN MIXING IN AT TIMES. THE STRENGTH OF THE ARCTIC AIR MASS...AND THE BAROCLINIC ZONE IT HAS LAID ACROSS EAST KENTUCKY...IS EVIDENCED BY THE MID TEENS CURRENTLY IN NORTHERN FLEMING COUNTY...LOW 20S ALONG THE WESTERN HALF OF THE MOUNTAIN PARKWAY...AND MID 30S BARELY HOLDING ON OVER THE FAR SOUTHEAST. NORTHEAST WINDS CONTINUE TO PUSH THE COLD AIR DEEPER INTO THE CWA WITH EVEN SOME GUSTS TO 15 OR 20 KTS SHOWING UP IN THE OBS CLOSER TO THE BLUEGRASS. THIS WILL ADD TO THE CONCERN FOR POWER OUTAGES AND TREE DAMAGE. ON RADAR...AN EXTENDED MASS OF PCPN REMAINS TO TRANSITION THROUGH EAST KENTUCKY WHERE IT WILL BE CONVERTED TO MAINLY SLEET AND SNOW...THOUGH FOR A TIME HEAVY RAIN AND FREEZING RAIN WILL BE POSSIBLE ACROSS THE FAR SOUTHEAST. NO CG RETURNS HAVE SHOWN UP WITH THE NORTHERN PORTION OF THIS SYSTEM IN AWHILE...BUT WOULD NOT RULE OUT SOME IN CLOUD OR CLOUD TO CLOUD BOLTS ACROSS THE AREA FOR THE NEXT SEVERAL HOURS. THE MODELS ARE IN GOOD AGREEMENT WITH THE MID LEVELS AND THE SHORTWAVE RESPONSIBLE FOR THE SFC SYSTEM GIVING US A LION OF A START TO MARCH. THIS WAVE IS CURRENTLY TRAVERSING NORTHERN ARKANSAS AND WILL ROLL NEARLY DUE EAST INTO THE SOUTHERN APPALACHIANS BY EVENING. THE MODEL AGREEMENT ALOFT DOES NOT TRANSLATE TO AGREEMENT AT THE SFC FOR A COMPLEX ONGOING SYSTEM SUCH AS THIS. SO...HAVE INSTEAD LEANED ON THE LATEST GUIDANCE FROM THE HRRR AND THE NAM12 COMBINED WITH TRENDS AND PCPN PROGRESSION TO GUIDE THE NEAR TERM FORECAST. THE HEAVY PCPN...GRADUALLY GOING TO SNOW AND FALLING AT OVER AN INCH AN HOUR...WILL MOVE THROUGH THE AREA EARLY THIS MORNING WITH A BACK EDGE AND A TAPER REACHING FAR WESTERN PARTS OF THE CWA BY 7 AM AND SWEEPING EAST BY 10 AM. HAVE USED THIS FOR TIMING THE WORST OF THE WEATHER. WILL CONTINUE THE MENTION OF THUNDER INTO THE PRE DAWN HOURS FOR THIS HEAVY PCPN BAND. THE SNOW TOTALS WILL BE LIMITED BY THE SLEET...THOUGH...SO IN A SENSE WE ARE DODGING A BULLET...BUT THE ROADS WILL TAKE THE BRUNT OF THIS STORM...AS A RESULT. THE HRRR ALSO SHOWS THE LAST OF THE DEFORMATION ZONE...BASICALLY WHAT IS GOING ON NEAR THE UPPER LOW IN SOUTHWEST MISSOURI CURRENTLY...PASSING THROUGH DURING THE EARLY AFTERNOON HOURS WITH AN ADDITIONAL INCH OR TWO OF SNOW POSSIBLE BEFORE IT TAPERS OFF AN ENDS FROM WEST TO EAST. HAVE DRAWN UP THE GRIDS WITH THESE TWO PCPN AREAS AND THEIR PROGRESS IN MIND. ACCORDINGLY...WILL HOLD ON TO THE WARNINGS AS THEY ARE WITH SOME CLEAN UP POSSIBLE TOWARD 12Z. WILL ALSO KEEP THE FLOOD WATCH AS HEAVY PCPN IN A SEMI-LIQUID FORM IS STILL EXPECTED FOR MUCH OF THAT AREA. EXPECT A GENERAL 3 TO 5 INCH SNOW AND SLEET ACCUMULATION THROUGH THE NORTHERN PART OF THE CWA WITH SLIGHTLY LESSER AMOUNTS SOUTH...BUT JUST AS MUCH SLEET...1/2 TO 1 INCH...THROUGHOUT THE ENTIRE AREA. THIS WILL BE DELINEATED FURTHER IN THE FORTHCOMING WSW UPDATES. USED THE CONSSHORT FOR TEMPERATURES...DEWPOINTS...AND WINDS...BC VERSION FOR THE LATTER TWO...THROUGH 00Z TUESDAY. ALSO DERIVED THE MAX AND MIN TEMPS FROM THE HOURLY TEMP GRIDS. AS FOR POPS...ENDED UP JUST ON THE HIGH SIDE OF ALL GUIDANCE WITH THE TAPER OF THE SNOW DURING THE DAYLIGHT HOURS TODAY. ...TONIGHT THROUGH TUESDAY... ONCE THIS SYSTEM MOVES TO THE SE OF THE REGION THIS EVENING...A STRONG MASS OF HIGH PRESSURE WILL TAKE HOLD ACROSS THE OHIO RIVER VALLEY...WITH UPPER LEVEL RIDGING FINALLY TAKING SHAPE ACROSS MUCH OF THE CONUS. THIS SET UP SHOULD KEEP KY DRY FOR THE NEXT 24 HOURS...AS WELL AS USHER IN DRY CANADIAN AIR INTO THE REGION. WITH THE PASSAGE OF THE COLD FRONT...AND THIS PUSH OF COLDER...DRIER CANADIAN AIR...EXPECT LOWS TO DROP DOWN WELL BELOW NORMAL ONCE MORE TONIGHT. OVERNIGHT LOWS ARE ONLY EXPECTED TO BE IN THE SINGLE DIGITS ABOVE ZERO ACROSS THE NORTHERN CWA...TO THE LOW TEENS IN THE SOUTHERN COUNTIES. WITH THE FRONTAL SYSTEM THAT JUST PASSED THROUGH...WINDS WERE GUSTY IN MANY LOCATIONS. LUCKILY...EXPECT THESE WINDS TO DIE DOWN BY TONIGHT. THIS WILL HAVE GOOD AND BAD IMPLICATIONS. ON THE DOWN SIDE...LIGHTER WINDS...IN ADDITION TO CLEAR SKIES AND A COOLER AIR MASS OVERHEAD...WILL PROVIDE OPTIMAL RADIATIONAL COOLING...HENCE THE EXPECTED OVERNIGHT LOW TEMPS. ON THE UP SIDE...WITH TEMPERATURES EXPECTED TO DROP THIS LOW...ANY AMOUNT OF WIND WILL ONLY AID TO THE WIND CHILL FACTOR...MAKING CONDITIONS FEEL EVEN COLDER THAN THEY REALLY ARE. THAT BEING SAID...WINDS WILL NOT BE NIL. WE CAN EXPECT LIGHT WINDS IN THE 3 TO 7 KT RANGE...WHICH WILL STILL BE ENOUGH TO DROP WIND CHILL READINGS DOWN INTO THE SINGLE DIGITS BELOW ZERO ACROSS THE NORTH. COLD AIR WILL CONTINUE TO FILTER IN DURING THE DAY TUESDAY...BUT HIGHER SUN ANGLES FOR MARCH...AND AN ABUNDANT AMOUNT OF SUNSHINE WITH THIS DRY AIR MASS IN PLACE...THIS WILL HELP TEMPERATURES TO BOUNCE BACK TO JUST ABOVE FREEZING IN THE NORTH...AND POSSIBLY INTO THE LOW 40S ACROSS THE FAR SOUTHEAST COUNTIES. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 421 AM EST MON MAR 3 2014 A SURFACE HIGH PRESSURE RIDGE OVER THE REGION WILL BE BREAKING DOWN AT THE START OF THE PERIOD...BUT DRY AIR WILL STILL BE IN PLACE AND THEIR WILL BE NO SIGNIFICANT UPPER LEVEL FEATURES THROUGH AT LEAST WEDNESDAY...SO THE WEATHER WILL REMAIN UNEVENTFUL. ON WEDNESDAY NIGHT...AN AMPLIFYING TROUGH WILL BE DROPPING SE TOWARD THE LOWER MISSISSIPPI VALLEY. MODELS ARE NOW LESS INCLINED TO CLOSE OFF A MID/UPPER LEVEL LOW WITH THIS SYSTEM...AND AS A RESULT THEY ARE MORE PROGRESSIVE WITH IT. SURFACE DEVELOPMENT IS STILL INDICATED OVER THE GULF...BUT IT TRACKS FURTHER EAST THAN IN RUNS OF RECENT DAYS. AS A RESULT...IT IS LOOKING LESS LIKELY THAT WE WILL SEE DIRECT EFFECTS FROM THE CYCLOGENESIS. HOWEVER...THE MID/UPPER LEVEL TROUGH COULD BRING SOME LIGHT RAIN ON THURSDAY OR THURSDAY EVENING AS IT PASSES. A TRANSITORY RIDGE AT THE SURFACE AND ALOFT WILL THEN MOVE THROUGH ON FRIDAY AND FRIDAY NIGHT...WITHOUT ANY COOLING IN THE WAKE OF THE DEPARTING SYSTEM. ANOTHER LARGE SCALE MID/UPPER LEVEL TROUGH AND ITS ASSOCIATED COLD FRONT ARE EXPECTED TO HEAD IN FROM THE NW DURING THE WEEKEND. GFS AND ECMWF AGREE ON THE BIG PICTURE FOR THIS...BUT SHOW SOME TIMING DIFFERENCES. TAKING BOTH INTO CONSIDERATION...THE MOST LIKELY TIME FOR PRECIP WILL BE SATURDAY NIGHT. WITH THE UNCERTAINTY...HAVE KEPT POPS IN THE CHANCE CATEGORY EVEN FOR SATURDAY NIGHT...WITH A BUFFER OF LOWER POPS ON BOTH SIDES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1225 PM EST MON MAR 3 2014 LIFR AND IFR CONDITIONS WILL BE THE RULE THIS MORNING ACROSS THE AREA AS THE LAST ROUND OF LIGHT TO MODERATE SNOW MOVES THROUGH EAST KENTUCKY. FAR SOUTHEAST PARTS OF THE STATE ARE NOW ALL SNOW. CONDITIONS WILL BEGIN TO IMPROVE FROM WEST TO EAST TOWARDS MID AFTERNOON. VFR WX SHOULD TAKE OVER THE REGION LATER THIS AFTERNOON AND LAST INTO THE NIGHT. WINDS WILL BE NORTHEAST AROUND 10 KTS WITH GUSTS TO 20 KTS POSSIBLE...BEFORE SETTLING TO LESS THAN 10 KTS AND BECOME MORE EASTERLY LATER THIS AFTERNOON AND INTO THE NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR KYZ044- 050>052. WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR KYZ058>060-068-069-104-106>109-111-112-114. WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR KYZ079-080- 083>088-110-113-115>120. && $$ UPDATE...JP SHORT TERM...GREIF/JMW LONG TERM...HAL AVIATION...DUSTY
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1216 PM EST MON MAR 3 2014 .UPDATE... ISSUED AT 1215 PM EST MON MAR 3 2014 ONE UPDATE HAS BEEN ISSUED THIS MORNING TO FINE TUNE TEMPS AND POPS SO AS TO BETTER TIME THE DEFORMATION BAND SOUTHEAST ACROSS THE CWA. SNOWFALL RATES IN THIS BAND HAVE BEEN ABOUT ONE INCH PER HOUR WITH UP TO 2 INCHES HAVING FALLEN IN THIS BAND IN SOME AREAS NEAR AND TO THE NORTH OF THE MOUNTAIN PARKWAY. ATTM...THE NORTHWEST COUNTIES LOOK ON TARGET TO CANCEL THE WINTER STORM WARNING AS THE SNOW HAS ALREADY ENDED...BUT DIFFICULT TRAVEL REMAINS...ESPECIALLY ON SECONDARY AND UNTREATED ROADS. AN SPS WILL LIKELY BE ISSUED AS SEGMENTS ARE DROPPED FROM THE WINTER STORM WARNING. UPDATE ISSUED AT 745 AM EST MON MAR 3 2014 WENT AHEAD AND UPDATED THE TEXT PRODUCTS TO REMOVE THE FLOOD WATCH IN THE SOUTH AND ALSO DROP THE HEAVY SNOW AND THUNDER MENTION. ALSO FINE TUNED TEMPERATURES AND DEWPOINTS THROUGH THE NEXT FEW HOURS FOR OBS AND TRENDS. THESE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. IN ADDITION...THE ZONES AND HWO WERE UPDATED. UPDATE ISSUED AT 615 AM EST MON MAR 3 2014 THE BACK EDGE OF THE HEAVIER PCPN IS NOW MOVING THROUGH THE SOUTHERN PART OF THE CWA. WHEN THIS EXITS WE WILL LOSE MUCH OF THE CONVECTIVE PCPN AND THREAT OF THUNDER. LIGHTER SNOWS WILL CONTINUE OFF AND ON FOR MUCH OF THE DAY UNTIL THE DEFORMATION ZONES PASSES THROUGH EAST KENTUCKY LATER THIS AFTERNOON. HAVE UPDATED THE GRIDS TO REFLECT THE LATEST RADAR TRENDS AND GUIDANCE FROM THE HRRR AND 06Z NAM12. ALSO FINE TUNED THE T AND TD GRIDS FOR THE NEXT SEVERAL HOURS PER THE LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. A MORE COMPLETE UPDATE TO THE TEXT PRODUCTS WILL TAKE PLACE WITH THE EXPIRATION OF THE FLOOD WATCH AT 7 AM. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 315 AM EST MON MAR 3 2014 ...THE REST OF THE NIGHT THROUGH TODAY... ...MAJOR WINTER STORM CONTINUES THROUGH THE MORNING... 07Z SFC ANALYSIS...AND RADAR/SATELLITE IMAGERY...SHOWS A WELL DEFINED LOW PRESSURE AREA ROLLING EAST NORTHEAST THROUGH THE TENNESSEE VALLEY. THIS IS RUNNING ALONG AN ARCTIC BOUNDARY THAT CONTINUES TO SAG SOUTH THROUGH THE THIN REMAINDER OF THE STATE NOT IN THE DEEP FREEZE. THE WARM NOSE WITH THIS SYSTEM REMAINS AN ISSUE FOR MUCH OF THE AREA ALONG AND SOUTH OF THE MOUNTAIN PARKWAY...PER OBS AND THE TRANSITION SHOWING UP IN THE DOPPLER CC LOOP. A PERIOD OF FREEZING RAIN HAS BEEN DEPOSITING GENERALLY BETWEEN A TENTH TO A QUARTER OF AN INCH OF ICE BEFORE THE SLEET STARTS TO REALLY ACCUMULATE FOR MOST PLACES. REPORTS OF HALF INCH SLEET TOTALS ARE STARTING TO COME IN FROM PLACES NORTH AND WEST OF JKL. THE OFFICE IS PUSHING THAT TOTAL...AS WELL...THOUGH SOME SNOW HAS BEEN MIXING IN AT TIMES. THE STRENGTH OF THE ARCTIC AIR MASS...AND THE BAROCLINIC ZONE IT HAS LAID ACROSS EAST KENTUCKY...IS EVIDENCED BY THE MID TEENS CURRENTLY IN NORTHERN FLEMING COUNTY...LOW 20S ALONG THE WESTERN HALF OF THE MOUNTAIN PARKWAY...AND MID 30S BARELY HOLDING ON OVER THE FAR SOUTHEAST. NORTHEAST WINDS CONTINUE TO PUSH THE COLD AIR DEEPER INTO THE CWA WITH EVEN SOME GUSTS TO 15 OR 20 KTS SHOWING UP IN THE OBS CLOSER TO THE BLUEGRASS. THIS WILL ADD TO THE CONCERN FOR POWER OUTAGES AND TREE DAMAGE. ON RADAR...AN EXTENDED MASS OF PCPN REMAINS TO TRANSITION THROUGH EAST KENTUCKY WHERE IT WILL BE CONVERTED TO MAINLY SLEET AND SNOW...THOUGH FOR A TIME HEAVY RAIN AND FREEZING RAIN WILL BE POSSIBLE ACROSS THE FAR SOUTHEAST. NO CG RETURNS HAVE SHOWN UP WITH THE NORTHERN PORTION OF THIS SYSTEM IN AWHILE...BUT WOULD NOT RULE OUT SOME IN CLOUD OR CLOUD TO CLOUD BOLTS ACROSS THE AREA FOR THE NEXT SEVERAL HOURS. THE MODELS ARE IN GOOD AGREEMENT WITH THE MID LEVELS AND THE SHORTWAVE RESPONSIBLE FOR THE SFC SYSTEM GIVING US A LION OF A START TO MARCH. THIS WAVE IS CURRENTLY TRAVERSING NORTHERN ARKANSAS AND WILL ROLL NEARLY DUE EAST INTO THE SOUTHERN APPALACHIANS BY EVENING. THE MODEL AGREEMENT ALOFT DOES NOT TRANSLATE TO AGREEMENT AT THE SFC FOR A COMPLEX ONGOING SYSTEM SUCH AS THIS. SO...HAVE INSTEAD LEANED ON THE LATEST GUIDANCE FROM THE HRRR AND THE NAM12 COMBINED WITH TRENDS AND PCPN PROGRESSION TO GUIDE THE NEAR TERM FORECAST. THE HEAVY PCPN...GRADUALLY GOING TO SNOW AND FALLING AT OVER AN INCH AN HOUR...WILL MOVE THROUGH THE AREA EARLY THIS MORNING WITH A BACK EDGE AND A TAPER REACHING FAR WESTERN PARTS OF THE CWA BY 7 AM AND SWEEPING EAST BY 10 AM. HAVE USED THIS FOR TIMING THE WORST OF THE WEATHER. WILL CONTINUE THE MENTION OF THUNDER INTO THE PRE DAWN HOURS FOR THIS HEAVY PCPN BAND. THE SNOW TOTALS WILL BE LIMITED BY THE SLEET...THOUGH...SO IN A SENSE WE ARE DODGING A BULLET...BUT THE ROADS WILL TAKE THE BRUNT OF THIS STORM...AS A RESULT. THE HRRR ALSO SHOWS THE LAST OF THE DEFORMATION ZONE...BASICALLY WHAT IS GOING ON NEAR THE UPPER LOW IN SOUTHWEST MISSOURI CURRENTLY...PASSING THROUGH DURING THE EARLY AFTERNOON HOURS WITH AN ADDITIONAL INCH OR TWO OF SNOW POSSIBLE BEFORE IT TAPERS OFF AN ENDS FROM WEST TO EAST. HAVE DRAWN UP THE GRIDS WITH THESE TWO PCPN AREAS AND THEIR PROGRESS IN MIND. ACCORDINGLY...WILL HOLD ON TO THE WARNINGS AS THEY ARE WITH SOME CLEAN UP POSSIBLE TOWARD 12Z. WILL ALSO KEEP THE FLOOD WATCH AS HEAVY PCPN IN A SEMI-LIQUID FORM IS STILL EXPECTED FOR MUCH OF THAT AREA. EXPECT A GENERAL 3 TO 5 INCH SNOW AND SLEET ACCUMULATION THROUGH THE NORTHERN PART OF THE CWA WITH SLIGHTLY LESSER AMOUNTS SOUTH...BUT JUST AS MUCH SLEET...1/2 TO 1 INCH...THROUGHOUT THE ENTIRE AREA. THIS WILL BE DELINEATED FURTHER IN THE FORTHCOMING WSW UPDATES. USED THE CONSSHORT FOR TEMPERATURES...DEWPOINTS...AND WINDS...BC VERSION FOR THE LATTER TWO...THROUGH 00Z TUESDAY. ALSO DERIVED THE MAX AND MIN TEMPS FROM THE HOURLY TEMP GRIDS. AS FOR POPS...ENDED UP JUST ON THE HIGH SIDE OF ALL GUIDANCE WITH THE TAPER OF THE SNOW DURING THE DAYLIGHT HOURS TODAY. ...TONIGHT THROUGH TUESDAY... ONCE THIS SYSTEM MOVES TO THE SE OF THE REGION THIS EVENING...A STRONG MASS OF HIGH PRESSURE WILL TAKE HOLD ACROSS THE OHIO RIVER VALLEY...WITH UPPER LEVEL RIDGING FINALLY TAKING SHAPE ACROSS MUCH OF THE CONUS. THIS SET UP SHOULD KEEP KY DRY FOR THE NEXT 24 HOURS...AS WELL AS USHER IN DRY CANADIAN AIR INTO THE REGION. WITH THE PASSAGE OF THE COLD FRONT...AND THIS PUSH OF COLDER...DRIER CANADIAN AIR...EXPECT LOWS TO DROP DOWN WELL BELOW NORMAL ONCE MORE TONIGHT. OVERNIGHT LOWS ARE ONLY EXPECTED TO BE IN THE SINGLE DIGITS ABOVE ZERO ACROSS THE NORTHERN CWA...TO THE LOW TEENS IN THE SOUTHERN COUNTIES. WITH THE FRONTAL SYSTEM THAT JUST PASSED THROUGH...WINDS WERE GUSTY IN MANY LOCATIONS. LUCKILY...EXPECT THESE WINDS TO DIE DOWN BY TONIGHT. THIS WILL HAVE GOOD AND BAD IMPLICATIONS. ON THE DOWN SIDE...LIGHTER WINDS...IN ADDITION TO CLEAR SKIES AND A COOLER AIR MASS OVERHEAD...WILL PROVIDE OPTIMAL RADIATIONAL COOLING...HENCE THE EXPECTED OVERNIGHT LOW TEMPS. ON THE UP SIDE...WITH TEMPERATURES EXPECTED TO DROP THIS LOW...ANY AMOUNT OF WIND WILL ONLY AID TO THE WIND CHILL FACTOR...MAKING CONDITIONS FEEL EVEN COLDER THAN THEY REALLY ARE. THAT BEING SAID...WINDS WILL NOT BE NIL. WE CAN EXPECT LIGHT WINDS IN THE 3 TO 7 KT RANGE...WHICH WILL STILL BE ENOUGH TO DROP WIND CHILL READINGS DOWN INTO THE SINGLE DIGITS BELOW ZERO ACROSS THE NORTH. COLD AIR WILL CONTINUE TO FILTER IN DURING THE DAY TUESDAY...BUT HIGHER SUN ANGLES FOR MARCH...AND AN ABUNDANT AMOUNT OF SUNSHINE WITH THIS DRY AIR MASS IN PLACE...THIS WILL HELP TEMPERATURES TO BOUNCE BACK TO JUST ABOVE FREEZING IN THE NORTH...AND POSSIBLY INTO THE LOW 40S ACROSS THE FAR SOUTHEAST COUNTIES. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 421 AM EST MON MAR 3 2014 A SURFACE HIGH PRESSURE RIDGE OVER THE REGION WILL BE BREAKING DOWN AT THE START OF THE PERIOD...BUT DRY AIR WILL STILL BE IN PLACE AND THEIR WILL BE NO SIGNIFICANT UPPER LEVEL FEATURES THROUGH AT LEAST WEDNESDAY...SO THE WEATHER WILL REMAIN UNEVENTFUL. ON WEDNESDAY NIGHT...AN AMPLIFYING TROUGH WILL BE DROPPING SE TOWARD THE LOWER MISSISSIPPI VALLEY. MODELS ARE NOW LESS INCLINED TO CLOSE OFF A MID/UPPER LEVEL LOW WITH THIS SYSTEM...AND AS A RESULT THEY ARE MORE PROGRESSIVE WITH IT. SURFACE DEVELOPMENT IS STILL INDICATED OVER THE GULF...BUT IT TRACKS FURTHER EAST THAN IN RUNS OF RECENT DAYS. AS A RESULT...IT IS LOOKING LESS LIKELY THAT WE WILL SEE DIRECT EFFECTS FROM THE CYCLOGENESIS. HOWEVER...THE MID/UPPER LEVEL TROUGH COULD BRING SOME LIGHT RAIN ON THURSDAY OR THURSDAY EVENING AS IT PASSES. A TRANSITORY RIDGE AT THE SURFACE AND ALOFT WILL THEN MOVE THROUGH ON FRIDAY AND FRIDAY NIGHT...WITHOUT ANY COOLING IN THE WAKE OF THE DEPARTING SYSTEM. ANOTHER LARGE SCALE MID/UPPER LEVEL TROUGH AND ITS ASSOCIATED COLD FRONT ARE EXPECTED TO HEAD IN FROM THE NW DURING THE WEEKEND. GFS AND ECMWF AGREE ON THE BIG PICTURE FOR THIS...BUT SHOW SOME TIMING DIFFERENCES. TAKING BOTH INTO CONSIDERATION...THE MOST LIKELY TIME FOR PRECIP WILL BE SATURDAY NIGHT. WITH THE UNCERTAINTY...HAVE KEPT POPS IN THE CHANCE CATEGORY EVEN FOR SATURDAY NIGHT...WITH A BUFFER OF LOWER POPS ON BOTH SIDES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 625 AM EST MON MAR 3 2014 LIFR AND IFR CONDITIONS WILL BE THE RULE THIS MORNING ACROSS THE AREA AS LIGHT TO MODERATE SNOW MOVES THROUGH EAST KENTUCKY. FAR SOUTHEAST PARTS OF THE STATE ARE STILL EXPERIENCING SOME SLEET AND FREEZING RAIN. CONDITIONS WILL BEGIN TO IMPROVE FROM WEST TO EAST TOWARDS MID MORNING...BUT ANOTHER ROUND OF MAINLY LIGHT SNOW WILL MOVE IN DURING THE EARLY AFTERNOON AND CONTINUE CONDITIONS IN THE MVFR AND IFR RANGE FOR A BUT LONGER. VFR WX SHOULD TAKE OVER THE REGION LATER THIS AFTERNOON AND LAST INTO THE NIGHT. WINDS WILL BE NORTHEAST AROUND 10 KTS WITH GUSTS TO 20 KTS POSSIBLE THROUGH MIDDAY...BEFORE SETTLING TO LESS THAN 10 KTS AND BECOME MORE EASTERLY LATER THIS AFTERNOON AND INTO THE NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR KYZ044- 050>052. WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR KYZ058>060-068-069-104-106>109-111-112-114. WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR KYZ079-080- 083>088-110-113-115>120. && $$ UPDATE...JP SHORT TERM...GREIF/JMW LONG TERM...HAL AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
329 PM EST MON MAR 3 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 328 PM EST MON MAR 3 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEP MID/UPPER LEVEL LOW CENTERED OVER NRN QUEBEC. WITH THE ASSOCIATED TROF EXTENDING W INTO WRN CANADA...ARCTIC AIR CONTINUES TO COVER MUCH OF CANADA INTO THE NRN CONUS...BUT THE COLD IS MODERATING OVER THE UPPER GREAT LAKES WITH 850 MB TEMPS CLOSER TO -15C TODAY. THIS SHOULD ALLOW HIGH TEMPS TO REACH INTO THE MID TO UPPER TEENS ACROSS MUCH OF THE AREA...REBOUNDING FROM BITTER COLD LOW TEMPS LAST NIGHT. THE LATEST WATER VAPOR IMAGERY ALSO SHOWS A SHORTWAVE MOVING FROM ERN MT INTO THE WRN DAKOTAS. ISENTROPIC ASCENT AHEAD OF THIS FEATURE OVER THE 280-285K LAYER AND UPPER DIVERGENCE IN RIGHT ENTRANCE REGION OF JET STREAK NOSING INTO THE UPPER GREAT LAKES IS PRODUCING LIGHT SNOW OVER EASTERN NORTH DAKOTA AND CENTRAL MN AS NOTED ON REGIONAL RADAR LOOP. THIS SNOW IS FCST TO SPREAD INTO THE UPPER GREAT LAKES THIS EVENING AND OVERNIGHT. WITH THE TRACK OF THE SHORTWAVE PROGGED BY 12Z MODELS TO DIVE SE OVER SRN/CNTRL WI...THE BEST AND LONGEST SUSTAINED DEEP LAYER Q-VECT CONV AND ISENTROPIC ASCENT WILL BE GENERALLY CONFINED TO THE WI BORDER COUNTIES AND ALONG THE BAY OF GREEN BAY. THUS...WILL CONTINUE TO CARRY THE HIGHEST POPS ACROSS THE S (LIKELY) WITH LOWER CHC POPS TO THE NW ACROSS THE KEWEENAW. WITH MIXING RATIOS AROUND 1G/KG AVBL PER 280K SFC (ROUGHLY 730MB) AND 6HRS OR SO OF -SN...EXPECT SNOW ACCUMULATIONS OF LESS THAN 1 INCH NORTH TO PERHAPS 1-2INCHES FAR SCNTRL...CLOSER TO STRONGER FORCING. WITH THICKENING CLOUDS EXPECTED...TEMPS AT MANY LOCATIONS WILL PROBABLY NOT FALL BLO 0F TONIGHT. EXPECT SNOW TO TAPER OFF FROM THE WEST LATE TONIGHT INTO EARLY TUE AS THE SHORTWAVE AND ASSOC BEST FORCING SLIDE SE OF THE AREA WITH LESS THAN HALF AN INCH OF ADDITIONAL ACCUMULATION OVER THE ERN COUNTIES. ANOTHER SHORTWAVE MOVING DOWN FROM SCNTRL CANADA WILL BRING SLIGHTLY COLDER AIR INTO THE REGION (8H TEMPS DOWN TO -18C) ON TUESDAY AS WINDS SHIFT NORTHERLY. EXPECT HIGH TEMPS GENERALLY FROM LOWER TO MID TEENS NORTH TO UPPER TEENS SOUTH UNDER MAINLY CLOUDY SKIES. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 317 PM EST MON MAR 3 2014 OVERALL...A FAIRLY QUIET LONG TERM PERIOD IS IN STORE FOR THE UPPER GREAT LAKES REGION THROUGH THE BEGINNING OF NEXT WEEK. MODIS IMAGERY OVER THE LAST TWO DAYS INDICATES LAKE SUPERIOR IS NEARLY ICED OVER...SO EVEN THOUGH TEMPERATURES ALOFT WILL STILL BE BELOW NORMAL DON/T EXPECT MUCH POTENTIAL FOR LAKE EFFECT SNOWS. TUESDAY EVENING THE AREA WILL BE BETWEEN WEAK SHORTWAVES...WITH THE ONE AFFECTING THE SOUTHERN AREA TONIGHT INTO TUESDAY MORNING WILL BE SHIFTING EAST AND THE NEXT WAVE WILL BE LOCATED IN THE DAKOTAS. THIS SECOND WAVE WILL FOLLOW A SIMILAR BUT SLIGHTLY FARTHER SOUTH TRAJECTORY AS THE TUESDAY MORNING WAVE...BUT THE NORTHERLY FLOW BEHIND THE FIRST SHORTWAVE WILL PULL DRIER AIR OVER LAKE SUPERIOR AND UPPER MICHIGAN AND LIMIT THE MOISTURE AVAILABLE FOR SNOW OVER MUCH OF THE AREA. THE BEST LOW LEVEL MOISTURE IS OVER THE SOUTH HALF OF THE AREA...BUT WITH MOST OF THE MODELS INDICATING IT BEING SHALLOW...WILL CONTINUE THE DRY FORECAST AND MAINLY INDICATE MOSTLY CLOUDY SKIES. ANOTHER STRONGER SHORTWAVE WILL DIVE SOUTH FROM ONTARIO AND ACROSS LAKE SUPERIOR LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. BUT WITH THE DRY AIR IN PLACE...WOULDN/T EXPECT MUCH INFLUENCE WITH THIS WAVE...ESPECIALLY WITH A MOSTLY FROZEN LAKE SUPERIOR. HIGH PRESSURE RIDGE FROM A HIGH IN EASTERN ONTARIO WILL BUILD BACK INTO THE UPPER GREAT LAKES BEHIND THE SHORTWAVE ON WEDNESDAY AFTERNOON AND REMAIN INTO WEDNESDAY NIGHT. MODELS DO VARY ON HOW QUICKLY THIS HIGH SHIFTS EAST THROUGH THURSDAY MORNING. WITH THE EXPECTED CLEAR SKIES AND LIGHT WINDS IN THE EVENING...SHOULD SEE A QUICK FALL IN TEMPS BEFORE RETURN FLOW TRIES TO DEVELOP OVERNIGHT. SINCE PWAT VALUES ARE AROUND 25 PERCENT OF NORMAL IN THE EVENING...DID LOWER TEMPS SEVERAL DEGREES BASED OFF THE CONSISTENCY IN THE MODELS ON HAVING LOWS IN THE -5 TO -10 DEGREE RANGE. THE BEST OPPORTUNITY FOR MEASUREABLE SNOW IN THE LONG TERM PERIOD WILL BE ON THURSDAY AFTERNOON INTO FRIDAY MORNING. THIS IS DUE TO A SHORTWAVE AND LOW PRESSURE SYSTEM MOVING THROUGH SOUTHERN CANADA...WHICH WILL DRAG A COLD FRONT ACROSS THE UPPER GREAT LAKES REGION. THE BEST FORCING WILL BE WELL TO THE NORTH OF THE CWA...BUT THERE IS A SECONDARY SHORTWAVE THAT QUICKLY SHIFTS EAST AND ACROSS THE U.P. LATE THURSDAY NIGHT INTO FRIDAY MORNING AND WILL BE THE MAIN FOCUS FOR THE SNOW. WITH THE CONSISTENCY IN THE MODELS...WILL TREND POPS UP IN THE CHANCE CATEGORY AND THINK SNOW AMOUNTS OF 1-2 INCHES ARE POSSIBLE OVER THE SOUTHEAST HALF OF THE CWA. BEHIND THIS FRONT...A HIGH PRESSURE RIDGE BUILDS BACK INTO THE AREA THROUGH SUNDAY (FROM A HIGH MOVING THROUGH THE CENTRAL PLAINS) AND WILL LEAD TO GENERALLY QUIET WEATHER WITH LAKE SUPERIOR PRETTY MUCH FROZEN OVER. THERE ARE HINTS OF A SHORTWAVE MOVING THROUGH ON SATURDAY NIGHT...BUT WITH THE ATMOSPHERE GENERALLY DRY...WOULDN/T EXPECT MORE THAN SOME PASSING CLOUDS. A COLD FRONT MOVING THROUGH THE AREA ON SUNDAY NIGHT INTO MONDAY (SIMILAR TO THURSDAY NIGHT) WILL BRING ANOTHER CHANCE OF SNOW TO THE AREA. AS FOR HIGHS...VALUES WILL STILL BE BELOW NORMAL THROUGHOUT THE PERIOD BUT WARMER THAN WE HAVE EXPERIENCED RECENTLY. 850MB TEMPS STAY IN THE TEENS BELOW ZERO MOST OF THE WEEK AND LIMITS HIGHS FROM RISING MUCH ABOVE THE UPPER TEENS AND LOWER 20S. BUT THERE IS THE POTENTIAL FOR SOME UPPER 20S LATE IN THE WEEKEND AHEAD OF THE NEXT FRONT. SOME OF THE THE 00Z ECMWF ENSEMBLE MEMBERS (AROUND 40 PERCENT) DO SHOW TEMPS RISING ABOVE FREEZING OVER THE SOUTHWEST HALF OF THE CWA ON SUNDAY...WHICH WOULD BE THE FIRST TIME FOR MOST OF THE CWA SINCE FEB 21ST. 12Z GFS ON THE OTHER HAND HAS BEST OPPORTUNITY FOR TEMPS AROUND FREEZING ON MONDAY...SO WILL BE SOMETHING TO KEEP AN EYE ON. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1246 PM EST MON MAR 3 2014 WITH VERY DRY LOW LEVEL AIR ACROSS THE REGION AND NEAR COMPLETE ICE COVER ON LAKE SUPERIOR...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO THE EARLY EVENING. HIGH AND MID CLOUDS WILL GRADUALLY INCREASE THIS AFTN/EVENING AHEAD OF THE NEXT DISTURBANCE. -SN WILL THEN OVERSPREAD THE AREA TONIGHT...BRINGING MVFR CONDITIONS. NOT OUT OF THE QUESTION THAT VIS COULD DROP TO IFR FOR A TIME AT KIWD/KSAW. LOOK FOR SNOW TO TAPER OFF FROM THE WEST LATE TONIGHT INTO TUE MORNING...ALTHOUGH MVFR CIGS SHOULD REMAIN THRU 18Z TUE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 328 PM EST MON MAR 3 2014 A SFC TROF MOVING ACROSS THE AREA LATER TONIGHT/TUE...WILL RESULT IN A WEAKER PRES GRADIENT. AS A RESULT...WINDS WILL FALL BACK UNDER 20KT TONIGHT THRU TUE. WINDS WILL REMAIN UNDER 20KT THRU WED. SOUTHERLY WINDS WILL THEN BE ON THE INCREASE THU AHEAD OF A LOW PRES TROF APPROACHING FROM THE W. TROF WILL CROSS THE UPPER LAKES FRI...BRINGING A WIND SHIFT TO THE NW. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
318 PM EST MON MAR 3 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 514 AM EST MON MAR 3 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEP MID/UPPER LEVEL LOW CENTERED OVER NRN QUEBEC. WITH TROF EXTENDING W INTO WRN CANADA... ARCTIC AIR CONTINUES TO COVER A VAST AREA OF CANADA INTO THE NRN CONUS. HOWEVER...THE COLD IS MODERATING AS 00Z RAOBS SHOWED 850MB TEMPS OF -21C/-17C/-21C AT KINL/KGRB/KAPX RESPECTIVELY...ALL SEVERAL DEGREES HIGHER THAN 24 HRS AGO. COLD WILL CONTINUE TO MODERATE OVER THE COMING DAYS AS PACIFIC AIR BEGINS TO SPREAD E IN LOW AMPLITUDE FLOW. SFC TROF THAT PUSHED ACROSS THE AREA LAST NIGHT BROUGHT A WIND SHIFT TO THE NW ACROSS LAKE SUPERIOR. A LONE LAKE EFFECT CLOUD/-SHSN BAND EMANATING FROM A PATCH OF OPEN WATER/BKN ICE NEAR ISLE ROYALE WAS EXTENDING SSE AND COMBINING WITH ADDITIONAL MOISTURE FROM SOME OPEN WATER/BKN ICE TO THE LEE OF THE KEWEENAW TO BRING FLURRIES/-SHSN TO PORTIONS OF EASTERN MARQUETTE/WRN ALGER COUNTY EARLY THIS MORNING. OTHERWISE...CLEAR SKIES/MOSTLY CALM WINDS AND A VERY DRY COLUMN HAVE ALLOWED TEMPS TO PLUMMET TO -10 TO -25F IN GENERAL. TODAY WILL BE A QUIET DAY WITH SUNSHINE GIVING WAY TO INCREASING HIGH CLOUDS FROM THE W IN ADVANCE OF SHORTWAVE CURRENTLY MOVING ACROSS THE NRN ROCKIES. MODERATING ARCTIC AIR MASS AND SUNSHINE WORKING ON LOWER ALBEDO FORESTED TERRAIN WILL HELP TEMPS RISE INTO THE TEENS IN MOST AREAS. TEMPS MAY STILL FAIL TO GET ABOVE 10F OVER THE KEWEENAW AND THE NE FCST AREA AS WINDS OFF THE FROZEN LAKE LIMIT MIXING DEPTH. NAM/GEM SHOW A LAKE BREEZE OR MAYBE MORE APPROPRIATE...ICE BREEZE...DEVELOPING INTO THE MARQUETTE AREA THIS AFTN. IF SO...TEMPS MAY FALL BACK SEVERAL DEGREES AFTER RISING INTO THE TEENS. ALTHOUGH TIMING IS NOT WELL AGREED UPON YET...MODELS ARE IN GOOD AGREEMENT THAT AN AREA OF -SN WILL SPREAD ACROSS UPPER MI AT SOME POINT TONIGHT AS AFOREMENTIONED SHORTWAVE MOVES ACROSS THE UPPER MISSISSIPPI VALLEY AND WRN GREAT LAKES. FCST AREA WILL BE ON THE NRN PORTION OF ISENTROPIC ASCENT/DEEP LAYER FORCING AS WELL AS UPPER DIVERGENCE ASSOCIATED WITH JET STREAK EXTENDING EASTWARD FROM NRN LAKE SUPERIOR/ONTARIO. THUS...POPS WILL BE HIGHEST ACROSS THE S (LIKELY) WITH CHC TO THE N. WITH MIXING RATIOS AROUND 1G/KG AVBL PER 280K SFC (ROUGHLY 700-725MB) AND 6HRS OR SO OF -SN...EXPECT SNOW ACCUMULATIONS OF LESS THAN 1 INCH N TO PERHAPS 1-2INCHES FAR SCNTRL...CLOSER TO STRONGER FORCING. WITH THICKENING CLOUDS...TEMPS AT MANY LOCATIONS WILL PROBABLY NOT FALL BLO 0F TONIGHT. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 317 PM EST MON MAR 3 2014 OVERALL...A FAIRLY QUIET LONG TERM PERIOD IS IN STORE FOR THE UPPER GREAT LAKES REGION THROUGH THE BEGINNING OF NEXT WEEK. MODIS IMAGERY OVER THE LAST TWO DAYS INDICATES LAKE SUPERIOR IS NEARLY ICED OVER...SO EVEN THOUGH TEMPERATURES ALOFT WILL STILL BE BELOW NORMAL DON/T EXPECT MUCH POTENTIAL FOR LAKE EFFECT SNOWS. TUESDAY EVENING THE AREA WILL BE BETWEEN WEAK SHORTWAVES...WITH THE ONE AFFECTING THE SOUTHERN AREA TONIGHT INTO TUESDAY MORNING WILL BE SHIFTING EAST AND THE NEXT WAVE WILL BE LOCATED IN THE DAKOTAS. THIS SECOND WAVE WILL FOLLOW A SIMILAR BUT SLIGHTLY FARTHER SOUTH TRAJECTORY AS THE TUESDAY MORNING WAVE...BUT THE NORTHERLY FLOW BEHIND THE FIRST SHORTWAVE WILL PULL DRIER AIR OVER LAKE SUPERIOR AND UPPER MICHIGAN AND LIMIT THE MOISTURE AVAILABLE FOR SNOW OVER MUCH OF THE AREA. THE BEST LOW LEVEL MOISTURE IS OVER THE SOUTH HALF OF THE AREA...BUT WITH MOST OF THE MODELS INDICATING IT BEING SHALLOW...WILL CONTINUE THE DRY FORECAST AND MAINLY INDICATE MOSTLY CLOUDY SKIES. ANOTHER STRONGER SHORTWAVE WILL DIVE SOUTH FROM ONTARIO AND ACROSS LAKE SUPERIOR LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. BUT WITH THE DRY AIR IN PLACE...WOULDN/T EXPECT MUCH INFLUENCE WITH THIS WAVE...ESPECIALLY WITH A MOSTLY FROZEN LAKE SUPERIOR. HIGH PRESSURE RIDGE FROM A HIGH IN EASTERN ONTARIO WILL BUILD BACK INTO THE UPPER GREAT LAKES BEHIND THE SHORTWAVE ON WEDNESDAY AFTERNOON AND REMAIN INTO WEDNESDAY NIGHT. MODELS DO VARY ON HOW QUICKLY THIS HIGH SHIFTS EAST THROUGH THURSDAY MORNING. WITH THE EXPECTED CLEAR SKIES AND LIGHT WINDS IN THE EVENING...SHOULD SEE A QUICK FALL IN TEMPS BEFORE RETURN FLOW TRIES TO DEVELOP OVERNIGHT. SINCE PWAT VALUES ARE AROUND 25 PERCENT OF NORMAL IN THE EVENING...DID LOWER TEMPS SEVERAL DEGREES BASED OFF THE CONSISTENCY IN THE MODELS ON HAVING LOWS IN THE -5 TO -10 DEGREE RANGE. THE BEST OPPORTUNITY FOR MEASUREABLE SNOW IN THE LONG TERM PERIOD WILL BE ON THURSDAY AFTERNOON INTO FRIDAY MORNING. THIS IS DUE TO A SHORTWAVE AND LOW PRESSURE SYSTEM MOVING THROUGH SOUTHERN CANADA...WHICH WILL DRAG A COLD FRONT ACROSS THE UPPER GREAT LAKES REGION. THE BEST FORCING WILL BE WELL TO THE NORTH OF THE CWA...BUT THERE IS A SECONDARY SHORTWAVE THAT QUICKLY SHIFTS EAST AND ACROSS THE U.P. LATE THURSDAY NIGHT INTO FRIDAY MORNING AND WILL BE THE MAIN FOCUS FOR THE SNOW. WITH THE CONSISTENCY IN THE MODELS...WILL TREND POPS UP IN THE CHANCE CATEGORY AND THINK SNOW AMOUNTS OF 1-2 INCHES ARE POSSIBLE OVER THE SOUTHEAST HALF OF THE CWA. BEHIND THIS FRONT...A HIGH PRESSURE RIDGE BUILDS BACK INTO THE AREA THROUGH SUNDAY (FROM A HIGH MOVING THROUGH THE CENTRAL PLAINS) AND WILL LEAD TO GENERALLY QUIET WEATHER WITH LAKE SUPERIOR PRETTY MUCH FROZEN OVER. THERE ARE HINTS OF A SHORTWAVE MOVING THROUGH ON SATURDAY NIGHT...BUT WITH THE ATMOSPHERE GENERALLY DRY...WOULDN/T EXPECT MORE THAN SOME PASSING CLOUDS. A COLD FRONT MOVING THROUGH THE AREA ON SUNDAY NIGHT INTO MONDAY (SIMILAR TO THURSDAY NIGHT) WILL BRING ANOTHER CHANCE OF SNOW TO THE AREA. AS FOR HIGHS...VALUES WILL STILL BE BELOW NORMAL THROUGHOUT THE PERIOD BUT WARMER THAN WE HAVE EXPERIENCED RECENTLY. 850MB TEMPS STAY IN THE TEENS BELOW ZERO MOST OF THE WEEK AND LIMITS HIGHS FROM RISING MUCH ABOVE THE UPPER TEENS AND LOWER 20S. BUT THERE IS THE POTENTIAL FOR SOME UPPER 20S LATE IN THE WEEKEND AHEAD OF THE NEXT FRONT. SOME OF THE THE 00Z ECMWF ENSEMBLE MEMBERS (AROUND 40 PERCENT) DO SHOW TEMPS RISING ABOVE FREEZING OVER THE SOUTHWEST HALF OF THE CWA ON SUNDAY...WHICH WOULD BE THE FIRST TIME FOR MOST OF THE CWA SINCE FEB 21ST. 12Z GFS ON THE OTHER HAND HAS BEST OPPORTUNITY FOR TEMPS AROUND FREEZING ON MONDAY...SO WILL BE SOMETHING TO KEEP AN EYE ON. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1246 PM EST MON MAR 3 2014 WITH VERY DRY LOW LEVEL AIR ACROSS THE REGION AND NEAR COMPLETE ICE COVER ON LAKE SUPERIOR...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO THE EARLY EVENING. HIGH AND MID CLOUDS WILL GRADUALLY INCREASE THIS AFTN/EVENING AHEAD OF THE NEXT DISTURBANCE. -SN WILL THEN OVERSPREAD THE AREA TONIGHT...BRINGING MVFR CONDITIONS. NOT OUT OF THE QUESTION THAT VIS COULD DROP TO IFR FOR A TIME AT KIWD/KSAW. LOOK FOR SNOW TO TAPER OFF FROM THE WEST LATE TONIGHT INTO TUE MORNING...ALTHOUGH MVFR CIGS SHOULD REMAIN THRU 18Z TUE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 514 AM EST MON MAR 3 2014 TIGHTENING PRES GRADIENT WILL RESULT WESTERLY WINDS INCREASING TO 15-25KT ACROSS MUCH OF LAKE SUPERIOR TODAY. SFC TROF THEN MOVES ACROSS THE AREA LATER TONIGHT/TUE...BRINGING A WEAKER PRES GRADIENT. AS A RESULT...WINDS WILL FALL BACK UNDER 20KT TONIGHT THRU TUE. WINDS WILL REMAIN UNDER 20KT THRU WED. SOUTHERLY WINDS WILL THEN BE ON THE INCREASE THU AHEAD OF A LOW PRES TROF APPROACHING FROM THE W. TROF WILL CROSS THE UPPER LAKES FRI...BRINGING A WIND SHIFT TO THE NW. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...SRF AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1250 PM EST MON MAR 3 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 514 AM EST MON MAR 3 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEP MID/UPPER LEVEL LOW CENTERED OVER NRN QUEBEC. WITH TROF EXTENDING W INTO WRN CANADA... ARCTIC AIR CONTINUES TO COVER A VAST AREA OF CANADA INTO THE NRN CONUS. HOWEVER...THE COLD IS MODERATING AS 00Z RAOBS SHOWED 850MB TEMPS OF -21C/-17C/-21C AT KINL/KGRB/KAPX RESPECTIVELY...ALL SEVERAL DEGREES HIGHER THAN 24 HRS AGO. COLD WILL CONTINUE TO MODERATE OVER THE COMING DAYS AS PACIFIC AIR BEGINS TO SPREAD E IN LOW AMPLITUDE FLOW. SFC TROF THAT PUSHED ACROSS THE AREA LAST NIGHT BROUGHT A WIND SHIFT TO THE NW ACROSS LAKE SUPERIOR. A LONE LAKE EFFECT CLOUD/-SHSN BAND EMANATING FROM A PATCH OF OPEN WATER/BKN ICE NEAR ISLE ROYALE WAS EXTENDING SSE AND COMBINING WITH ADDITIONAL MOISTURE FROM SOME OPEN WATER/BKN ICE TO THE LEE OF THE KEWEENAW TO BRING FLURRIES/-SHSN TO PORTIONS OF EASTERN MARQUETTE/WRN ALGER COUNTY EARLY THIS MORNING. OTHERWISE...CLEAR SKIES/MOSTLY CALM WINDS AND A VERY DRY COLUMN HAVE ALLOWED TEMPS TO PLUMMET TO -10 TO -25F IN GENERAL. TODAY WILL BE A QUIET DAY WITH SUNSHINE GIVING WAY TO INCREASING HIGH CLOUDS FROM THE W IN ADVANCE OF SHORTWAVE CURRENTLY MOVING ACROSS THE NRN ROCKIES. MODERATING ARCTIC AIR MASS AND SUNSHINE WORKING ON LOWER ALBEDO FORESTED TERRAIN WILL HELP TEMPS RISE INTO THE TEENS IN MOST AREAS. TEMPS MAY STILL FAIL TO GET ABOVE 10F OVER THE KEWEENAW AND THE NE FCST AREA AS WINDS OFF THE FROZEN LAKE LIMIT MIXING DEPTH. NAM/GEM SHOW A LAKE BREEZE OR MAYBE MORE APPROPRIATE...ICE BREEZE...DEVELOPING INTO THE MARQUETTE AREA THIS AFTN. IF SO...TEMPS MAY FALL BACK SEVERAL DEGREES AFTER RISING INTO THE TEENS. ALTHOUGH TIMING IS NOT WELL AGREED UPON YET...MODELS ARE IN GOOD AGREEMENT THAT AN AREA OF -SN WILL SPREAD ACROSS UPPER MI AT SOME POINT TONIGHT AS AFOREMENTIONED SHORTWAVE MOVES ACROSS THE UPPER MISSISSIPPI VALLEY AND WRN GREAT LAKES. FCST AREA WILL BE ON THE NRN PORTION OF ISENTROPIC ASCENT/DEEP LAYER FORCING AS WELL AS UPPER DIVERGENCE ASSOCIATED WITH JET STREAK EXTENDING EASTWARD FROM NRN LAKE SUPERIOR/ONTARIO. THUS...POPS WILL BE HIGHEST ACROSS THE S (LIKELY) WITH CHC TO THE N. WITH MIXING RATIOS AROUND 1G/KG AVBL PER 280K SFC (ROUGHLY 700-725MB) AND 6HRS OR SO OF -SN...EXPECT SNOW ACCUMULATIONS OF LESS THAN 1 INCH N TO PERHAPS 1-2INCHES FAR SCNTRL...CLOSER TO STRONGER FORCING. WITH THICKENING CLOUDS...TEMPS AT MANY LOCATIONS WILL PROBABLY NOT FALL BLO 0F TONIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 507 AM EST MON MAR 3 2014 A WEAK SHORTWAVE WILL BE OVER THE SERN CWA 12Z TUE...WITH THE BULK OF ANY LIGHT SNOW SE OF THE CWA AFTER 12Z TUE. HAVE SOME SLIGHT CHANCE POPS LINGERING BEHIND THE SYSTEM INTO TUE...BUT ONLY VERY MINOR SNOWFALL AMOUNTS ARE EXPECTED. HIGH PRESSURE TO THE NE OF THE CWA WILL KEEP THE FORECAST DRY ON WED...WITH AT LEAST CHANCES OF PRECIP RETURNING THU INTO FRI AS MODEL INDICATE THAT A SHORTWAVE MAY MOVE INTO THE REGION. THERE IS SIGNIFICANT MODEL DISAGREEMENT AND RUN TO RUN DISCONTINUITY WITH THE SHORTWAVE...SO USED A CONSENSUS OF GUIDANCE WHICH GAVE SLIGHT CHANCE TO LOW CHANCE POPS THU INTO FRI. SHOULD SEE WARMING TEMPS /BUT STILL BELOW NORMAL/ AHEAD OF THE SHORTWAVE THU AND FRI AS RETURN FLOW SETS UP ACROSS THE REGION...WITH HIGHS IN THE MID 20S TO NEAR 30 ON FRI. A COLDER AIRMASS AND DRY HIGH PRESSURE DOMINATE NEXT WEEKEND...WITH HIGHS IN THE LOW TO MID 20S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1246 PM EST MON MAR 3 2014 WITH VERY DRY LOW LEVEL AIR ACROSS THE REGION AND NEAR COMPLETE ICE COVER ON LAKE SUPERIOR...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO THE EARLY EVENING. HIGH AND MID CLOUDS WILL GRADUALLY INCREASE THIS AFTN/EVENING AHEAD OF THE NEXT DISTURBANCE. -SN WILL THEN OVERSPREAD THE AREA TONIGHT...BRINGING MVFR CONDITIONS. NOT OUT OF THE QUESTION THAT VIS COULD DROP TO IFR FOR A TIME AT KIWD/KSAW. LOOK FOR SNOW TO TAPER OFF FROM THE WEST LATE TONIGHT INTO TUE MORNING...ALTHOUGH MVFR CIGS SHOULD REMAIN THRU 18Z TUE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 514 AM EST MON MAR 3 2014 TIGHTENING PRES GRADIENT WILL RESULT WESTERLY WINDS INCREASING TO 15-25KT ACROSS MUCH OF LAKE SUPERIOR TODAY. SFC TROF THEN MOVES ACROSS THE AREA LATER TONIGHT/TUE...BRINGING A WEAKER PRES GRADIENT. AS A RESULT...WINDS WILL FALL BACK UNDER 20KT TONIGHT THRU TUE. WINDS WILL REMAIN UNDER 20KT THRU WED. SOUTHERLY WINDS WILL THEN BE ON THE INCREASE THU AHEAD OF A LOW PRES TROF APPROACHING FROM THE W. TROF WILL CROSS THE UPPER LAKES FRI...BRINGING A WIND SHIFT TO THE NW. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
506 PM EST MON MAR 3 2014 .SYNOPSIS... COLD HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST TONIGHT THROUGH WEDNESDAY AS WEAK LOW PRESSURE MOVES JUST OFF OF THE COAST. A DEVELOPING LOW PRESSURE SYSTEM WILL MOVE ALONG THE SOUTHEAST COAST THURSDAY AND FRIDAY. && .NEAR TERM /TONIGHT/... AS OF 445 PM MON...LATEST SURFACE ANALYSIS HAS THE ARCTIC COLD WELL SOUTH OF THE AREA STRETCHING FROM NEAR COLUMBIA SC TO FRYING PAN SHOALS. HIGH PRESSURE CONTINUES TO BUILD SOUTH OVER EASTERN NC THIS AFTERNOON. PRECIP HAS TRANSITIONED TO RAIN/SLEET/FREEZING RAIN MIX FROM KINSTON TO MANTEO AND NORTH...WITH SOME LIGHT ACCUMULATIONS NOTED ON A WEBCAM ALONG HWY 12 NEAR DUCK. BEST UPPER LEVEL DYNAMICS MOVE ACROSS THE AREA BETWEEN THIS EVENING EXPECT MOST OF THE PRECIP TO FALL DURING THIS TIME...EXCEPT PERHAPS ALONG THE IMMEDIATE COAST WHICH COULD CONTINUE INTO THE EARLY EVENING. FORECAST SOUNDINGS CONTINUE TO INDICATE A 3-6C WARM NOSE PERSISTING THROUGH THE EARLY EVENING...EXPECT THE RAIN TO TRANSITION TO MAINLY SLEET ALONG WITH WITH LIGHT FREEZING RAIN AS THE SFC COLD POOL WILL QUICKLY DEEPEN TO AROUND 3KFT. MOST OF THE HEAVIEST QPF FELL AS RAIN EARLIER THIS AFTERNOON PRIOR TO COLD AIR ARRIVAL. THERE WILL BE LIMITED TIME FROM WHEN THE THERMAL PROFILES FAVOR SLEET TO WHEN RAPID DRYING COMMENCES IN THE DENDRITIC GROWTH ZONE LATE IN THE AFTERNOON BRINGING A TRANSITION TO LIGHT FREEZING RAIN OR FREEZING DRIZZLE. THEREFORE...SLEET AND ICE ACCUMULATIONS ARE EXPECTED TO BE MINIMAL...GENERALLY ONE TO TWO TENTHS OF AN INCH OF SLEET AND TRACE TO PERHAPS A TENTH OF AN INCH OF ICE. THERMAL PROFILES FOR AREAS FROM AROUND RODANTHE SOUTH ALONG THE OUTER BANKS SUGGEST MAINLY RAIN FOR THESE AREAS...THOUGH COULD SEE SOME LIGHT SLEET LATE. HAVE MADE MINIMAL CHANGES TO THE FORECAST AND WILL MAINTAIN THE WINTER WEATHER ADVISORY FOR LIGHT SLEET AND ICE. REFREEZING OF ELEVATED SURFACES SUCH AS BRIDGES AND OVERPASSES WILL BE POSSIBLE THROUGH TONIGHT. LATEST HRRR AND RAP HAVE A GOOD HANDLE ON CURRENT PRECIP PATTERN...WITH SOME INLAND LOCATIONS SOUTH OF HWY 64 BECOMING MORE PATCHY IN NATURE WHILE NORTH OF HWY 64 REMAINS IN GREATER COVERAGE OF WINTRY MIX. WITH BEST UPPER LIFT SHIFTING OVER THE REGION THE NEXT FEW HOURS...CURRENT TIMING OF PRECIP APPEARS ON TRACK...WITH ENDING FROM WEST TO EAST LATE THIS EVENING FOR THE COASTAL PLAIN AND PERSISTING ALONG THE COAST THROUGH TUES MORNING. STRONG CAA WILL BRING GUSTY NORTHERLY WINDS ACROSS THE REGION THROUGH MIDNIGHT AS WINDS GUST 35 TO 45 MPH. THESE WINDS WILL ALSO BRING MINOR WATER LEVEL RISES ALONG THE SOUTHERN PORTION OF THE PAMLICO SOUND BUT WITH THE SHORT DURATION ONLY AROUND 6-9 HOURS NOT ANTICIPATING MUCH MORE THAN 1 TO 1.5 FT ABOVE NORMAL...WHICH IS WHAT IS INDICATED ON THE CERA WEBSITE. TEMPS WILL FOLLOW A NON-DIURNAL TREND TONIGHT UNDER STRONG COLD AIR ADVECTION. MAINTAINED SLIGHT CHANCE POPS ALONG THE COAST FOR LINGERING DRIZZLE/RAIN AFTER MIDNIGHT WITH SOME FREEZING DRIZZLE POSSIBLE FOR WESTERN CARTERET AND ONSLOW COUNTIES WHERE TEMPS WILL LIKELY DROP WELL BELOW FREEZING. && .SHORT TERM /TUESDAY/... AS OF 330 AM MON...HIGH PRESSURE WILL PERSIST OVER THE REGION TUES WITH A STRONG INVERSION 1-2KFT FT ALOFT WITH NEAR SATURATION UP TO 8-9K FT. COLD MORNING TEMPS WILL STRUGGLE TO CLIMB INTO THE 30S BUT EXPECT TEMPS NEAR FREEZING FOR INLAND LOCATIONS BY MID MORNING. WILL MAINTAIN WINTER WEATHER ADVISORIES FOR THE REGION AS BLACK ICE WILL BE POSSIBLE ON UNTREATED ROADS CONTINUING TO BRING HAZARDOUS DRIVING CONDITIONS. LOW PRESSURE WILL DEVELOP WELL OFF THE CAROLINA COAST AND HELP TO WRAP AROUND SOME LOW LEVEL MOISTURE BY LATE AFTERNOON. FORECAST SOUNDINGS INDICATE THE LOWER LEVELS WILL REMAIN SATURATED BELOW 8-9K FT TOMORROW SO EXPECT LIGHT RAIN/DRIZZLE DURING THE DAY. BIGGEST CHANGE WITH THE FORECAST PACKAGE TODAY WAS TO ADD SLIGHT CHANCE RAIN OR DRIZZLE FOR MOST OF THE AREA TUESDAY AFTERNOON. TEMPS WILL BE WELL BELOW NORMAL WITH HIGHS STRUGGLING TO REACH THE UPPER 30S FOR INLAND SECTIONS TO MID 40S ACROSS SOUTHERN AND COASTAL SECTIONS. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... AS OF 300 PM MONDAY...NAM/ECMWF MODEL BLEND USED FOR TUE NIGHT-WED...THEN ECMWF/GFS/WPC BLEND FOR THU-MONDAY. ACTIVE SRN STREAM WITH COLD HIGH PRES WEDGED IN OVER AREA WILL PRODUCE COOL AND WET PERIOD THROUGH END OF WEEK...THEN SOME MODERATION OVER WEEKEND WITH RIDGING SFC AND ALOFT. ANOTHER WEAK SHRT WV WILL MOVE ACROSS AREA FROM SW TUE NIGHT INTO EARLY WED. MODELS INDICATE MAIN THREAT OF PCPN WILL BE ALONG COAST CLOSER TO BAROCLINIC ZONE...AND WILL CARRY HIGHEST POPS THERE BUT CONTINUE TO CAP AT 50% DUE TO MODEL DIFFERENCES. 30% CHANCE POPS FOR COASTAL PLAINS AND WILL MENTION PSBL FREEZING RAIN THERE WITH MIN TEMPS 30-32. NO ICING ACCUMULATION EXPECTED AT THIS TIME BUT WILL CONTINUE TO MONITOR THREAT WITH LATER MODEL RUNS. ADDITIONAL WEAK ENERGY WILL CONTINUE TO MOVE ACROSS FORM SW WED AFTN AND WED NIGHT BUT MODELS INDICATE PCPN REMAINING MAINLY OFFSHORE...THUS WILL CONTINUE ONLY SLIGHT CHC POPS FOR COAST. NO P-TYPE ISSUES EXPECTED WITH TEMPS REMAINING ABOVE FREEZING. 12Z GFS AND ECMWF HAVE COME INTO BETTER AGREEMENT WITH NEXT SYSTEM WITH BOTH NOW INDICATING OPEN TROF EVOLVING INTO UPR LOW MOVING ACROSS JUST S OF AREA THU NIGHT-FRI NIGHT. THIS WILL RESULT IN SFC LOW MOVING OUT OF GULFMEX AND DEEPENING JUST S OF AREA FRIDAY BEFORE MOVING OFFSHORE LATE FRI NIGHT...PRODUCING NOR`EASTER TYPE CONDITIONS FOR ERN NC. GDNC INDICATES ATMOS WILL BE WARMER ENOUGH FOR ALL RAIN...BUT PROLONGED NE WINDS MAY RESULT IN HIGH SURF AND COASTAL FLOODING ISSUES...AND SOME AREAS COULD SEE 1 TO 2 INCHES OF RAIN. COASTAL SECTIONS COULD ALSO SEE PERIOD OF 25 TO 35 MPH WINDS AND WIND ADVISORIES MAY BE NEEDED. CONTINUED HIGHEST POPS AT LIKELY FOR ALL AREAS THU AFTN INTO FRIDAY...GRADUALLY TAPERING FROM W TO E FRI NIGHT. IN WAKE OF UPR LOW...RIDGING SFC AND ALOFT WILL WARMER AND DRIER CONDITIONS FOR SAT. WEAK NRN STREAM SHRT WV WILL PUSH A WEAK COLD FRONT THROUGH SUNDAY WITH JUST SLIGHT CHANCE OF A SHOWER. RIDGING AND DRY AGAIN FOR MONDAY. COOL WEDGE CONDITIONS WILL KEEP TEMPS 5-10 DEGS BELOW NORMAL FOR TUE NIGHT-FRI...THEN NEAR OR ABOVE NORMAL FOR SAT-MON. && .AVIATION /22Z MONDAY THROUGH SATURDAY/... SHORT TERM /THROUGH SUNDAY EVENING/... AS OF 1245 PM MON...COLD FRONT HAS CROSSED ALL TAF SITES WITH STRONG NORTHERLY WINDS GUSTING UP TO 20 KTS BEING OBSERVED. CEILING HEIGHTS HAVE BEEN LOWERING WITHIN THE PAST HOUR TO MVFR...WITH CEILING HEIGHTS TO LOWER WITH THE PASSAGE OF PRECIP ACROSS ALL TAF SITES. SFC TEMPS WILL FALL TO BELOW FREEZING LATE AFTERNOON TO EARLY EVENING WHILE TEMPS ALOFT REMAIN ABOVE FREEZING BRINGING A TRANSITION TO LIGHT SLEET AND FREEZING RAIN THIS EVENING...THEN FREEZING DRIZZLE LATE THIS EVENING WITH DRYING ALOFT. EXPECTING PRECIP TO END APPROX BEFORE MIDNIGHT AT ALL TAF SITES WITH CONDITIONS IMPROVING TO MVFR OVERNIGHT. LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 300 PM MONDAY...OVERALL POOR FLYING WEATHER FORECAST THROUGH MUCH OF THE PERIOD. COOL WEDGE CONDITIONS WILL LIKELY KEEP SUB-VFR CIGS OVER MOST OF AREA TUE NIGHT THROUGH WED NIGHT...THEN BE REINFORCED FOR WDSPRD PCPN WITH COASTAL SFC LOW THU INTO FRIDAY NIGY. SOME LIGHT FREEZING RAIN PSBL LATE TUE NIGHT FOR KPGV AND KISO. GUSTY NE WINDS PSBL FOR KOAJ AND KEWN THU INTO FRIDAY AS WELL. CONDITIONS IMPROVING TO VFR FOR SAT WITH RIDGING SFC AND ALOFT. && .MARINE... SHORT TERM /THROUGH TUESDAY/... AS OF 5 PM MONDAY...LATEST SURFACE AND BUOY DATA INDICATE STRONG N/NE WINDS 25-30 KT WITH GUSTS TO 35 KT AND SEAS ELEVATED 9-11 FT FOR THE NORTHERN WATERS. STRONG CAA IN NLY FLOW WILL CONTINUE OVERNIGHT THEN SLOWLY DIMINISH TUESDAY. GALE WARNINGS WILL LIKELY BECOME REPLACED WITH SCAS LATE TONIGHT FOR ELEVATED SEAS AND GUSTY WINDS. LOCAL SWAN/NWPS HAD A MUCH BETTER HANDLE ON HIGH SEAS FOR THE NORTHERN WATERS WHILE THE 12Z WAVEWATCH REMAINS 3-4 FT TOO LOW...THUS USED LOCAL SWAN FOR SHORT TERM SEAS FORECAST. SEAS 10-13 FT WILL SUBSIDE 7-10 FT TUESDAY...WITH 4-7 FT FOR THE SOUTHERN WATERS. LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 400 PM SUNDAY...VERY POOR BOATING CONDITIONS THROUGH FRI NIGHT WITH SOME IMPROVEMENT SAT. NE WINDS DIMINISH EARLY TUE NIGT...BUT WILL INCREASE AGAIN BY WED MORNING WITH WEAK SFC LOW DEVELOPMENT OFFSHORE. A PROLONGED PERIOD OF AT LEAST SCA CRITERIA WINDS LIKELY FOR THU-FRI AS SLOW MOVING NOR`EASTER TYPE LOW MOVES ALONG JUST S AND SE OF WATERS. PER LONG-TERM DISCUSSION ABOVE...HIGH SURF...BEACH EROSION AND COASTAL FLOODING WILL BE LIKELY IF LOW MOVES AS EXPECTED. CONFIDENCE HAS INCREASED SLIGHTLY WITH 12Z ECMWF AND GFS IN BETTER BUT STILL ONLY MODERATE CONFIDENCE AT THIS TIME. CONTINUED TO USE NWPS THROUGH WED NIGHT...THEN LEANED TO WW3 FOR REST OF PERIOD. SEAS WILL SUBSIDE TUE NIGHT AND MAY DROP BELOW 6 FT FOR A PERIOD...BUT WILL THEN BUILD AGAIN WED AND THU...WITH PROLONGED PERIOD OF AT LEAST 8-11 FT SEAS FOR THU NIGHT AND FRIDAY. SEAS SUBSIDING FRI NIGHT AND SAT AS LOW MOVES WELL OFFSHORE BUT 6 FT HEIGHTS LIKELY LINGERING OUTER PORTIONS NRN WATERS THROUGH SAT. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...WINTER WEATHER ADVISORY UNTIL 11 AM EST TUESDAY FOR NCZ029- 044>047-079>081-103. WINTER WEATHER ADVISORY UNTIL 11 AM EST TUESDAY FOR NCZ090>095- 098. WIND ADVISORY UNTIL 1 AM EST TUESDAY FOR NCZ095-103-104. MARINE...GALE WARNING UNTIL 1 AM EST TUESDAY FOR AMZ130-135-150-152-154- 156-158. && $$ SYNOPSIS...DAG NEAR TERM...SK/DAG SHORT TERM...SK/DAG LONG TERM...JBM AVIATION...JBM/BM/SK MARINE...JBM/DAG
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
327 PM EST MON MAR 3 2014 .SYNOPSIS... A STRONG COLD FRONT WILL CONTINUE TO PUSH OFFSHORE TONIGHT...WITH MUCH COLDER AND BLUSTERY CONDITIONS EXPECTED TONIGHT AND TUESDAY. SOME LIGHT FROZEN PRECIPITATION IS ALSO POSSIBLE. COLD HIGH PRESSURE WILL WEDGE ACROSS THE AREA INTO THURSDAY...CONTINUING COOL AND UNSETTLED WEATHER AS A WAVE OF LOW PRESSURE MOVES ALONG THE COAST. A STRONGER LOW PRESSURE SYSTEM WILL TRACK UP THE COAST THURSDAY INTO FRIDAY WITH POSSIBLY HEAVY RAINFALL. HIGH PRESSURE WILL BUILD BACK INTO THE AREA BEHIND THIS SYSTEM FRIDAY AND INTO THE WEEKEND. ANOTHER COLD FRONT WILL CROSS THE AREA SUNDAY NIGHT. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 300 PM MONDAY...ARCTIC FRONT CURRENTLY STEAMING SOUTH ACROSS THE CWA...WITH SOME 20 DEGREE SPREAD IN CURRENT TEMPS BETWEEN NORTHERN AND SOUTHERN AREAS. PRECIPITATION COVERAGE AND AMOUNTS HAVE BEEN CONSIDERABLY LOWER THAN FORECAST/MODELED...A FACT THAT MAY BE QUITE RELEVANT TO THE REMAINDER OF THE PERIOD. AS THE COLD AIR CONTINUES ITS CHARGE THERMAL PROFILES WILL BEGIN TO SUPPORT FREEZING RAIN OR POSSIBLY EVEN SLEET. THIS WILL HAPPEN EARLIEST OVER NRN ZONES...IN THE 00Z TO 03Z TIME FRAME. TROUBLE IS...THIS IS THE SAME TIME THAT THE MID LEVELS BEGIN TO DRY OUT...AND RATHER EMPHATICALLY. THUS THE OPPORTUNITY FOR MEASURABLE PRECIPITATION OVER A GIVEN AREA APPEARS TO BE VERY SHORT IN NATURE...IF AT ALL. OVERALL POPS HAVE BEEN LOWERED THROUGH THE PERIOD AND SHOWN TO TAPER OFF TO NON-MEASURABLE MORE QUICKLY. WHAT FORECASTS DO SHOW WELL BETWEEN VARIOUS MODELS IS A CONTINUED SATURATION THROUGH THE LOWEST 6KFT OF THE ATMOSPHERE. DESPITE THERE BEING A DRY MID LAYER AND NO REAL LIFT TO SPEAK OF THIS IMPLIES THAT THERE COULD BE SOME FREEZING DRIZZLE FROM TIME TO TIME JUST ABOUT ANYWHERE AREA-WIDE. OPERATIONAL MODELS DO INDICATE AS SUCH AND IT HAS BEEN IN PREV FORECAST SO IT WILL BE MAINTAINED HERE. BUT EVEN THE LIKELY OVERDONE OPERATIONAL MODELS SHOW NO MEASURABLE PRECIP AND SREF PROBS OF 0.01 DROP OFF COMPLETELY BY 06Z. THE HRRR SEEMS TO HAVE A DECENT HANDLE ON CURRENT RADAR TRENDS AND GOES DRY BY 01Z...BARELY INTO THE WINDOW OF OPPORTUNITY FOR PTYPE ISSUES. THIS ALL PAIRED WITH THE RECENT WARM WEATHER WE HAVE BEEN STRESSING THAT LITTLE TO NO IMPACTS TO TRAVEL ARE ANTICIPATED. THIS HAS MADE IT DIFFICULT TO FIGURE OUT HOW TO HANDLE THE CURRENT WW ADVISORY IN PLACE FOR NRN ROW OF COUNTIES. WAS QUITE TEMPTED TO DROP IT...BUT WILL ALLOW NEXT SHIFT THAT DECISION ESP SINCE JUST A HUNDREDTH OF AN INCH OF FZRA WOULD NECESSITATE IT BEING IN EFFECT AND ONE WOULD HATE TO LOWER IT ONLY TO HAVE IT SUBSEQUENTLY RE-ISSUED IN SUCH A SHORT TIME. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...A HIGHLY UNSETTLED PERIOD OF WEATHER THROUGH MID-WEEK AS AN ARCTIC FRONT STALLS OFFSHORE WHILE WAVES OF LOW PRESSURE MOVE ALONG IT. PERIOD BEGINS WITH A WEDGE OF HIGH PRESSURE BANKED ALONG THE EAST COAST BEHIND AN ARCTIC FRONT STALLED JUST OFFSHORE. ALOFT...SW FLOW AHEAD DOWNSTREAM OF A WEAK TROUGH WILL CONTINUE WARM/MOIST FLOW ABOVE THE SURFACE WEDGE...WHILE SOME ENHANCED CONFLUENCE WILL ACTUALLY HELP REINFORCE ITS STRENGTH. THE BIGGEST QUESTION MARK TUESDAY REVOLVES AROUND WINTRY PRECIP POTENTIAL EARLY TUESDAY MORNING. NAM/GFS SOUNDINGS ARE IN VERY GOOD AGREEMENT THAT SURFACE TEMPS TUESDAY MORNING WILL BE BELOW FREEZING ACROSS MOST...IF NOT ALL...OF THE CWA...WHILE TEMPS BETWEEN 950MB AND 850MB WARM TO +2C TO +4C. MOIST LOW LEVELS OF THE COLUMN PERSIST ALL OF TUESDAY...BUT VERY DRY AIR EXISTS ABOVE 850MB...SUCH THAT PWATS REMAIN RATHER LOW...AROUND ONE-HALF INCH. SO THERE IS STILL CONSIDERABLE UNCERTAINTY AS TO THE POTENTIAL FOR PRECIP...EVEN MORE DETERMINING POSSIBILITY OF FREEZING RAIN. SOUNDINGS WOULD SUGGEST SOME LIGHT FREEZING DRIZZLE CONTINUING SEVERAL HOURS INTO TUESDAY AS TEMPS ONLY VERY SLOWLY WARM...LIKELY MUCH SLOWER THAN GUIDANCE DUE TO CLOUDS AND REINFORCING WEDGE. STILL...WILL CARRY ZL FOR ALL ZONES INTO TUESDAY MORNING...LASTING MAYBE A BIT LONGER IN THE NORTH. AGAIN...AM CONCERNED ABOUT LACK OF FORCING (ISENTROPIC LIFT IS VERY WEAK) AND THE DRY AIR ALOFT...SO WILL KEEP QPF AT 0 FOR NOW. THIS IS A VERY BORDERLINE SITUATION HOWEVER...SINCE SIMPLY A TRACE OF ZR REQUIRES A WW.Y...SO WILL NEED TO MONITOR WHAT WILL LIKELY BE A FLUID SITUATION OVERNIGHT INTO TUESDAY MORNING FOR POTENTIAL EXPANSION OF CURRENT WW.Y TO INCLUDE MORE OF THE CWA. A MORE IMPRESSIVE AREA OF PRECIP WILL BLOSSOM ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY...AS ISENTROPIC LIFT INCREASES DRAMATICALLY OVERHEAD IN CONJUNCTION WITH AN AREA OF LOW PRESSURE DEVELOPING OFFSHORE ALONG THE STALLED BOUNDARY. FORECAST PROFILES SATURATE CONSIDERABLY...AND MOS P12/P24 VALUES SKYROCKET TO THE HIGH LIKELY/LOW CATEGORICAL RANGE INTO WEDNESDAY. HOWEVER...THE NAM IS QUITE A BIT DRIER THAN THE GFS ON WEDNESDAY...AND WILL NOT BE AS AGGRESSIVE AS GFS IS SHOWING FOR QPF...BUT DEFINITELY BETTER RAIN CHANCES TUESDAY NIGHT/WED THAN TUESDAY MORNING. FORTUNATELY...TEMPS WILL HAVE WARMED ABOVE FREEZING BY TUESDAY NIGHT...SO JUST A COLD RAIN IS EXPECTED. ANOTHER BREAK IN PRECIP IS POSSIBLE AS ISENTROPIC LIFT WEAKENS LATE WEDNESDAY...BUT RENEWED HEAVIER RAIN IS LIKELY LATE IN THE PERIOD AND ON THURSDAY AS A SECOND AREA OF LOW PRESSURE DEVELOPS ALONG THE BOUNDARY OFFSHORE. INHERITED POP SHOWS INCREASING TO HIGH-CHC FROM SW TO NE TOWARDS THE END OF THE PERIOD...AND FEEL THIS IS WARRANTED SO WILL MAKE ONLY MINIMAL INCREASE TO THE WED NIGHT PORTION OF THE FORECAST. TEMPS WILL BE WELL BELOW NORMAL ON TUESDAY AS THE REINFORCING WEDGE COMBINED WITH CLOUD COVER AND PRECIP WILL PREVENT MUCH WARMING THROUGH THE DAY. EXPECT HIGHS WILL PEAK ONLY IN THE 30S MUCH OF THE AREA...BUT SOME LOW 40S POSSIBLE ALONG THE COAST. THIS IS 20 TO 30 DEGREES BELOW NORMAL FOR THE DATE! LITTLE VARIATION IN TEMPS FOR MINS TUESDAY NIGHT WITH LOWS IN THE LOW/MID 30S ACROSS THE AREA. SOME WARMING EXPECTED WEDNESDAY...BUT TEMPS WILL REMAIN WELL BELOW NORMAL...RISING INTO THE MID/UPR 40S...WITH LOWS WEDNESDAY NIGHT DROPPING BACK INTO THE MID/UPR 30S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM MONDAY...A CLASSIC COASTAL LOW SHOULD BE TAKING SHAPE OFF THE CAROLINA COAST THURSDAY...SPREADING PLENTY OF THICK CLOUDS AND RAIN ACROSS THE AREA. WITH 12Z GFS WAS IN EXCELLENT AGREEMENT WITH THE 00Z ECMWF REGARDING THE DEGREE OF ISENTROPIC LIFT AND LOW-LEVEL TEMPERATURES EXPECTED DURING THE DAY. HIGHS SHOULD ONLY REACH THE MID TO UPPER 40S. I HAVE RAISED POPS TO 80 PERCENT AND STORM-TOTAL QPF TO NEAR 1 INCH PENDING CONFIRMATION FROM ANOTHER ROUND OR TWO OF MODEL RUNS. THE STRONG UPPER LEVEL SYSTEM WILL ROLL ACROSS THE AREA EARLY FRIDAY MORNING. PLENTY OF MOISTURE ALOFT AND PERIODS OF LIFT SHOULD ALLOW RAIN TO CONTINUE...ESPECIALLY ALONG THE COAST INTO FRIDAY MORNING... WITH DRYING CONDITIONS DEVELOPING FROM WEST TO EAST DURING THE DAY. THE 12Z GFS LOOKED SIMILAR TO THE 00Z ECMWF...BUT THE 12Z ECMWF WAS MUCH SLOWER WITH THE EASTWARD PROGRESSION OF THE UPPER LEVEL SYSTEM AS IT BOMBS THE SURFACE LOW OFF THE NC COAST. ROUGHLY 20 PERCENT OF THE 12Z GFS ENSEMBLE SOLUTIONS SHOWED A STRONG SURFACE LOW LIKE THE 12Z ECMWF SITTING OFF THE COAST FRIDAY...SO THIS IDEA WILL HAVE TO BE WATCHED CLOSELY. ASSUMING WE GET SOME SUNSHINE BEHIND THE DEPARTING UPPER TROUGH FRIDAY HIGHS SHOULD REACH 53-57...COOLEST AT THE COAST. (OF COURSE IF THE 12Z ECMWF IS RIGHT AND WE STAY CLOUDY/ RAINY/WINDY MOST OF THE DAY THESE HIGHS COULD BE 10 DEGREES TOO OPTIMISTIC) SURFACE AND UPPER LEVEL RIDGING FINALLY BUILDS IN FRIDAY NIGHT AND SATURDAY WITH MAINLY CLEAR SKIES AND RISING HEIGHTS AND THICKNESSES. HIGHS IN THE 60S SATURDAY WILL SEEM WONDERFUL AFTER THURSDAY AND FRIDAY. THE SURFACE HIGH SHOULD PUSH OFFSHORE SATURDAY AFTERNOON WITH SOUTHWESTERLY SYNOPTIC WINDS PLUS THE DAYTIME SEABREEZE WORKING TOGETHER TO KEEP THE BEACHES CONSIDERABLY COOLER COMPARED TO INLAND LOCATIONS. SUNDAY...SUBTROPICAL JET STREAM MOISTURE SHOULD INCREASE ALOFT WITH CONSIDERABLE MID AND HIGH CLOUDS EXPECTED. THE 12Z GFS WAS MUCH FARTHER EAST THAN EITHER OF TODAY`S ECWMF RUNS WITH AN UPPER LEVEL SYSTEM CUTTING OFF IN THE DESERT SOUTHWEST SUNDAY. GOING WITH THE ECMWF SOLUTION MEANS WE SHOULD HAVE LITTLE POTENTIAL FOR PRECIPITATION EARLY NEXT WEEK...UNLESS A FEW SPRINKLES OR SHOWERS DEVELOP ALONG A SOUTHWARD-MOVING BACKDOOR COLD FRONT SLIDING DOWN THE EAST COAST SUNDAY EVENING. THIS BACKDOOR FRONT WILL BE THE RESULT OF AN UPPER TROUGH MOVING OFF THE NEW ENGLAND COAST SUNDAY...BUT SHOULD BRING LITTLE AIRMASS CHANGE SUNDAY NIGHT INTO MONDAY. && .AVIATION /21Z MONDAY THROUGH SATURDAY/... AS OF 12Z...AREA OF RAIN NOW IMPACTING KFLO AND KLBT WITH MVFR CONDITIONS FOR VISIBILITIES. THIS AREA OF RAIN IS EXPECTED TO WORK IT WAY TO THE COASTAL TAFS IN THE NEXT FEW HOURS. AN ARCTIC AIRMASS IS MOVING SOUTHWARD AND IT WILL BRING IN IFR CONDITIONS AS CEILINGS WILL LOWER LATER TODAY AND IN THE OVERNIGHT AREA. THERE IS A LOW PROBABILITY FOR FREEZING RAIN THROUGH 06 UTC AND FREEZING DRIZZLE FROM 06 TO 12 UTC TUESDAY. THE CONFIDENCE ON THIS FREEZING PRECIPITATION IS LOW ENOUGH TO KEEP OUT OF THE TAFS AT THIS TIME. CEILINGS ARE EXPECTED TO RISE INTO THE MVFR RANGE INLAND BY EARLY TUESDAY AND MID-MORNING AT THE COAST. EXTENDED OUTLOOK...MVFR/CHANCE SHOWERS THROUGH THE PERIOD. BEST CHANCE PRECIPITATION/IFR WED AND THURS EVNG THROUGH FRI. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM MONDAY...MOST OF THE AREA STILL IN THE PREFRONTAL SWRLY FLOW SAVE FOR PERHAPS NRN PENDER WATERS. 41013 SEEING WINDS CRANK UP INTO 25 TO 30 KT RANGE...THE LATTER GENERALLY GUSTS. ALTHOUGH GUIDANCE HAS COME IN WITH SOME SLIGHTLY LOWER WIND SPEEDS THAN PREVIOUS IT STILL LOOKS LIKE GALE FORCE GUSTS WILL BE FREQUENT ENOUGH TO WARRANT KEEPING GALE WARNING UP. EVEN PREVIOUS SHIFT HAD MENTIONED THAT IT WAS A MARGINAL CASE. THE SURFACE PRESSURE GRADIENT IS GOING TO HAVE LITTLE SUPPORT FROM ALOFT AS WINDS ALOFT STAY RATHER LACKLUSTER AND THERE IS CONSIDERABLE DIRECTIONAL SHEAR...BOTH OF WHICH WILL MEAN NO MIXING DOWN OF HIGHER WIND SPEEDS USUALLY ASSOCIATED WITH A COLD SURGE. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...ARCTIC FRONT WILL BE OFFSHORE AT THE START OF THE PERIOD...WITH A STRONG WEDGE OF HIGH PRESSURE BUILDING DOWN ALONG THE COAST BEHIND IT. THIS WEDGE WILL CONTROL THE LOCAL WIND TRAJECTORY THROUGH THE PERIOD...WITH A NE DIRECTION PERSISTENT THROUGH MID-WEEK. SPEEDS WILL CHANGE WITH THE FLUCTUATING GRADIENT...EASING FROM 15-25 KTS EARLY TUESDAY TO 10-15 KTS LATE TUESDAY...BEFORE INCREASING AGAIN TO 15-20 KTS WEDNESDAY NIGHT. SEAS WILL BE DRIVEN PRIMARILY BY A 6-7 NE WIND WAVE...WITH AMPLITUDES FALLING FROM 4-7 FT EARLY...TO 3-5 FT MUCH OF THE PERIOD...AND RISING AGAIN WEDNESDAY NIGHT TO 3-6 FT. A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED FOR PORTIONS OF THE SHORT TERM. LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 300 PM MONDAY...A CLASSIC COASTAL LOW WILL BE DEVELOPING OFF THE SOUTHEAST U.S. COAST THURSDAY. VIRTUALLY ALL MODEL GUIDANCE SHOWS MULTIPLE LOW PRESSURE CENTERS ALONG A LINE FROM FLORIDA TO NORTH CAROLINA THURSDAY MORNING CONSOLIDATING INTO A SINGLE LOW ABOUT 100 MILES OFF THE SOUTH CAROLINA COAST THURSDAY EVENING. THE LOW SHOULD STEADILY DEEPEN AS IT FOLLOWS THE GULF STREAM NORTHEASTWARD. AN EXTENDED PERIOD OF SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED FOR NORTHEAST/NORTH WINDS AND SEAS. MODELS DIVERGE IN HOW THEY HANDLE THE LOW FRIDAY: THE 12Z GFS AND 00Z ECMWF TAKE THE LOW OUT TO SEA WITH DIMINISHING IMPACTS FRIDAY AFTERNOON AND EVENING. THE 12Z ECMWF IS MARKEDLY DIFFERENT HOWEVER...SLOWING THE EASTWARD MOVEMENT OF LOW DOWN SIGNIFICANTLY ON FRIDAY AS IT BOMBS THE STORM DOWN TO BELOW 1000 MB CENTRAL PRESSURE WHILE OVER THE WARM WATER SOUTHEAST OF CAPE LOOKOUT. THIS SCENARIO COULD BRING NEAR-GALE FORCE WINDS ACROSS THE CAROLINA COASTAL WATERS FRIDAY PERSISTING INTO FRIDAY EVENING. IT APPEARS BY SATURDAY THE LOW SHOULD BE WELL OFFSHORE WITH HIGH PRESSURE BUILDING OVER THE AREA FROM THE WEST WITH MUCH LIGHTER WINDS AND QUICKLY DIMINISHING SEAS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...WINTER WEATHER ADVISORY UNTIL 7 AM EST TUESDAY FOR SCZ017-023- 024. NC...WINTER WEATHER ADVISORY UNTIL 7 AM EST TUESDAY FOR NCZ087-096- 105-106. MARINE...GALE WARNING UNTIL 6 AM EST TUESDAY FOR AMZ250-252-254-256. && $$ SYNOPSIS...JDW NEAR TERM...MBB SHORT TERM...JDW LONG TERM...TRA AVIATION...MBB/DRH MARINE...TRA/JDW/MBB
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
113 PM EST MON MAR 3 2014 .SYNOPSIS... AN ARCTIC COLD FRONT WILL MOVE SOUTH THROUGH THE AREA TODAY. COLD HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST TUESDAY AND WEDNESDAY AS WEAK LOW PRESSURE MOVES JUST OFF OF THE COAST. A DEVELOPING LOW PRESSURE SYSTEM WILL MOVE ALONG THE SOUTHEAST COAST THURSDAY AND FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 10 AM MON...MID MORNING UPDATE WAS MAINLY TO REFLECT CURRENT CONDITIONS. ADJUSTED POPS WITH THE LATEST HRRR AND WRF MODELS. MODELS ARE INDICATING PRECIP STARTING OUR WESTERN PART OF THE CWA APPROX 16Z...SO THEREFORE DECREASED POPS ALONG HWY 64 AND EAST OF HWY 17 TO SLIGHTLY CHANCE. LATEST SURFACE ANALYSIS HAS THE ARTIC COLD FRONT STRETCHING ACROSS GOLDSBORO TO CEDAR ISLAND. COLD FRONT WILL CONTINUE TO PUSH SOUTH ACROSS THE AREA THE MORNING INTO THE EARLY AFTERNOON WITH THE AREA OF LOW PRES PUSHING OFF CAPE FEAR THIS AFTERNOON AS A DAMPENING SHORTWAVE MOVES EWD ACROSS THE SOUTHEAST. MODELS IN FAIR AGREEMENT WITH THE FRONT NEAR THE ALBEMARLE SOUND AROUND 09Z...ALONG THE HIGHWAY 70 CORRIDOR AROUND 15Z AND PUSHING SOUTH OF THE AREA SHORTLY AFTER 18Z. PRECIP WILL DEVELOP BEHIND THE FRONTAL PASSAGE WITH OVERRUNNING MOISTURE AHEAD OF THE SHORTWAVE. BEST UPPER LEVEL DYNAMICS MOVE ACROSS THE AREA BETWEEN 18Z MON-00Z TUE AND EXPECT MOST OF THE PRECIP TO FALL DURING THIS TIME...EXCEPT PERHAPS ALONG THE IMMEDIATE COAST WHICH COULD CONTINUE INTO THE EARLY EVENING. INITIALLY PRECIP WILL FALL AS RAIN...BUT STRONG CAA ADVECTION WILL USHER IN A MUCH COLDER AIRMASS THROUGH THE DAY ALLOWING A WINTRY MIX TO DEVELOP FROM N TO S THROUGH THE AFTERNOON. WITH A 3-6C WARM NOSE PERSISTING THROUGH THE AFTERNOON...EXPECT THE RAIN TO TRANSITION TO MAINLY SLEET ALONG WITH WITH LIGHT FREEZING RAIN AS THE SFC COLD POOL WILL QUICKLY DEEPEN TO AROUND 3FT. MODEL/WPC AVERAGE STORM TOTAL LIQUID QPF IS AROUND A QUARTER TO A THIRD OF AN INCH. THERE WILL BE LIMITED TIME FROM WHEN THE THERMAL PROFILES FAVOR SLEET TO WHEN RAPID DRYING COMMENCES IN THE DENDRITIC GROWTH ZONE LATE IN THE AFTERNOON BRINGING A TRANSITION TO LIGHT FREEZING RAIN OR FREEZING DRIZZLE. THEREFORE...SLEET AND ICE ACCUMULATIONS ARE EXPECTED TO BE MINIMAL...GENERALLY ONE TO TWO TENTHS OF AN INCH OF SLEET AND TRACE TO PERHAPS A TENTH OF AN INCH OF ICE. THERMAL PROFILES FOR AREAS FROM AROUND RODANTHE SOUTH ALONG THE OUTER BANKS SUGGEST MAINLY RAIN FOR THESE AREAS...THOUGH COULD SEE SOME LIGHT SLEET LATE. HAVE MADE MINIMAL CHANGES TO THE FORECAST AND WILL MAINTAIN THE WINTER WEATHER ADVISORY FOR LIGHT SLEET AND ICE. STRONG CAA WILL BRING GUSTY NLY WINDS ACROSS THE REGION AFTER FROPA AND COULD SEE SUSTAINED WINDS APPROACH WIND ADVISORY LEVELS ACROSS THE OUTER BANKS AND PARTS OF DOWN EAST CARTERET COUNTY AND WILL ISSUE A WIND ADVISORY FROM MID AFTERNOON THROUGH MIDNIGHT WITH THE MORNING FORECAST PACKAGE. THESE WINDS WILL ALSO BRING MINOR WATER LEVEL RISES ALONG THE SOUTHERN PORTION OF THE PAMLICO SOUND BUT WITH THE SHORT DURATION ONLY AROUND 6-9 HRS NOT ANTICIPATING MUCH MORE THAN 1 TO 1.5 FT ABOVE NORMAL...WHICH IS WHAT IS INDICATED ON THE CERA WEBSITE. TEMPS WILL FOLLOW A NON-DIURNAL TREND WITH RAPID COOLING BEHIND THE FRONT. TEMPS CURRENTLY AROUND 48-58 ACROSS THE REGION EARLY THIS MORNING BUT EXPECT TEMPS TO QUICKLY FALL THROUGH THE 40S AND INTO THE 30S AFTER FROPA. THERE WILL LIKELY BE A LARGE SPREAD IN HIGHS TODAY WITH SOUTHERN SECTIONS LIKELY WARMING TO AROUND 60 THIS MORNING AHEAD OF THE FRONT WHILE NORTHERN SECTIONS WILL REACH THEIR HIGHS AROUND 50 AROUND DAYBREAK. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/... AS OF 330 AM MON...THE SHORTWAVE TROUGH QUICKLY PUSHES EAST OF THE AREA EARLY IN THE EVENING WITH UPPER LEVEL DYNAMICS QUICKLY DIMINISHING AND MID LEVEL DRYING ENDING BEST PRECIP PROCESSES. THERMAL PROFILES SUGGEST LIGHT FREEZING RAIN OR FREEZING DRIZZLE CONTINUING THROUGH THE EVENING HOURS MOST AREAS BUT ANY ADDITIONAL ACCUMULATION WILL BE VERY LIGHT. TEMPS WILL CONTINUE TO FALL INTO THE 20S MOST AREAS...EXCEPT 30-35 ALONG THE COAST...WITH BLACK ICE POSSIBLE ON UNTREATED ROADS CONTINUING TO BRING HAZARDOUS DRIVING CONDITIONS THROUGH THE OVERNIGHT. && .LONG TERM /TUESDAY THROUGH SUNDAY/... AS OF 255 AM MONDAY...FORECAST MODELS CONTINUE TO SHOW AN ACTIVE PATTERN ACROSS EASTERN NORTH CAROLINA FOR MOST OF THIS WEEK. ANY PRECIPITATION ON TUESDAY SHOULD BE NEAR THE COAST AS WAVE OF LOW PRESSURE MOVES WELL OFFSHORE AND HAVE KEPT LOW CHANCE POPS THRU THE DAY. COLD HIGH PRESSURE WILL WEDGE DOWN THE EASTERN SLOPES OF THE APPALACHIANS FROM THE NORTHEAST TUESDAY AFTERNOON AND WILL REMAIN LOCKED IN PLACE THROUGH LATE WEEK. THIS WILL KEEP TEMPERATURES BELOW SEASONAL NORMALS...BY SEVERAL DEGREES...AND KEEP SKIES RATHER CLOUDY FOR MOST OF THE WEEK. ANOTHER OFFSHORE WAVE OF LOW PRESSURE APPROACHES BY EARLY WEDNESDAY. WITH TEMPERATURES CLOSE TO FREEZING ACROSS THE FAR NORTHWESTERN CWA EARLY WEDNESDAY MORNING...HAVE KEPT A SMALL RISK OF SOME LIGHT FREEZING RAIN AS THE PRECIPITATION ARRIVES. THE PRECIPITATION SHOULD BECOME ALL RAIN AND CONTINUE INTO WEDNESDAY AFTERNOON BEFORE MOVING OFFSHORE. ANOTHER STRONGER WAVE OF LOW PRESSURE APPROACHES THURSDAY INTO FRIDAY. THE ECMWF IS NOT QUITE AS STRONG AS PREVIOUS RUNS...BUT BOTH THE ECMWF AND GFS SHOW A HIGH COVERAGE OF RAIN THURSDAY AND THURSDAY NIGHT. THERMAL PROFILES SUPPORT ALL RAIN WITH THIS SYSTEM...WITH LIKELY GUSTY WINDS AND THE POSSIBILITY OF MINOR COASTAL FLOODING ISSUES. A RIDGE OF HIGH PRESSURE WILL BUILD IN FROM THE SOUTH WITH A WARMER SOUTHWEST FLOW FOR SATURDAY. A FAST-MOVING COLD FRONT MAY LEAD TO ANOTHER QUICK SHOT OF RAIN ON SUNDAY. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... SHORT TERM /THROUGH SUNDAY EVENING/... AS OF 1245 AM MON...COLD FRONT HAS CROSSED ALL TAF SITES WITH STRONG NORTHERLY WINDS GUSTING UP TO 20 KTS BEING OBSERVED. CEILING HEIGHTS HAVE BEEN LOWERING WITHIN THE PAST HOUR TO MVFR...WITH CEILING HEIGHTS TO LOWER WITH THE PASSAGE OF PRECIP ACROSS ALL TAF SITES. SFC TEMPS WILL FALL TO BELOW FREEZING LATE AFTERNOON TO EARLY EVENING WHILE TEMPS ALOFT REMAIN ABOVE FREEZING BRINGING A TRANSITION TO LIGHT SLEET AND FREEZING RAIN THIS EVENING...THEN FREEZING DRIZZLE LATE THIS EVENING WITH DRYING ALOFT. EXPECTING PRECIP TO END APPROX BEFORE MIDNIGHT AT ALL TAF SITES WITH CONDITIONS IMPROVING TO MVFR OVERNIGHT. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 255 AM MONDAY...FLYING CONDITIONS WILL BE LESS THAN OPTIMAL FOR A GOOD PORTION OF THE EXTENDED PERIOD. A SERIES OF LOW PRESSURE WAVES WILL MOVE OFFSHORE WITH REDUCED CEILINGS AND VSBYS LIKELY FOR THE TUESDAY THROUGH THURSDAY PERIOD. THE INITIAL BAND OF RAIN WILL SPREAD BACK INTO THE REGION TUESDAY NIGHT AND CONTINUE THRU WEDNESDAY. ADDITIONAL RAINFALL WILL ACCOMPANY A STRONGER AREA OF LOW PRESSURE THURSDAY AND THURSDAY NIGHT. GUSTY WINDS WILL ALSO BE LIKELY ON THE BACKSIDE OF THESE WAVES OF LOW PRESSURE. HIGH PRESSURE BUILDS IN WITH DRIER AIR AND MORE VFR CONDITIONS FOR FRIDAY INTO SATURDAY. && .MARINE... SHORT TERM /THROUGH MONDAY NIGHT/... AS OF 1000 AM MONDAY...CURRENT MARINE IS IN GOOD SHAPE. ONLY MADE MINOR TWEAKS TO REFLECT CURRENT CONDITIONS. LATEST SURFACE ANALYSIS HAS THE ARTIC COLD FRONT ALONG CEDAR ISLAND. NORTH OF CEDAR ISLAND...WINDS HAVE SHIFTED TO NE 15 TO 20 KTS GUSTING UP TO 27 KTS. SEAS HAVE INCREASED IN OUR NORTHERN MARINE ZONE...5 TO 6 FT. SOUTH OF THE FRONT...WINDS REMAIN SW 10-20 KTS. COLD FRONT IS EXPECTED TO CONTINUE PUSH THROUGH THE WATERS...SOUTH OF THE REGION AROUND 2 PM. STRONG CAA IN NLY FLOW DEVELOPS BEHIND THE FRONT WITH GALE FORCE CONDITIONS DEVELOPING MID AFTERNOON THROUGH THE EVENING...ESPECIALLY IN GUSTS AROUND 35-40 KT. USED A BLEND OF THE PREVIOUS NWPS AND WAVEWATCH FOR SEAS...WEIGHING HIGHER TOWARD NWPS. SEAS WILL BUILD RAPIDLY THIS AFTN INTO TONIGHT WITH CAA SURGE...LIKELY PEAKING AT 10-12 FT NRN AND CENTRAL WATERS LATE TONIGHT. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 255 AM MONDAY...GUSTY WINDS AND ROUGH SEAS WILL CONTINUE THROUGH THE DAY ON TUESDAY BEFORE SUBSIDING IN THE EVENING AS HIGH PRESSURE STARTS TO BUILD DOWN THE EASTERN SLOPES OF THE MOUNTAINS. FROM WEDNESDAY INTO FRIDAY...SOLID SMALL CRAFT ADVISORY CONDITIONS ARE LIKELY AS A SERIES OF WAVES OF LOW PRESSURE MOVE OFFSHORE ALONG THE STALLED FRONT. THE STRONGEST OF THE WAVES MOVES OFFSHORE THURSDAY NIGHT THROUGH FRIDAY WITH STRONG SMALL CRAFT AND POTENTIAL GALE CONDITIONS POSSIBLE. PER WAVEWATCH GUIDANCE...SEAS WILL BUILD TO AS HIGH AS 8 TO 9 FEET...ESPECIALLY OVER THE CENTRAL WATERS THURSDAY INTO FRIDAY. HIGH PRESSURE BUILDS SOUTH OF THE COASTAL WATERS BY SATURDAY WITH DIMINISHING WINDS AND SEAS. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 11 AM EST TUESDAY FOR NCZ029-044>047-079>081-103. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST TUESDAY FOR NCZ090>095-098. WIND ADVISORY UNTIL 1 AM EST TUESDAY FOR NCZ095-103-104. MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 1 AM EST TUESDAY FOR AMZ135-152-154-156-158. GALE WARNING UNTIL 1 AM EST TUESDAY FOR AMZ130-150. && $$ SYNOPSIS...SK NEAR TERM...SK/BM SHORT TERM...SK/BM LONG TERM...CTC AVIATION...CTC/SK/BM MARINE...CTC/SK/BM
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
341 PM CST MON MAR 3 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 334 PM CST MON MAR 3 2014 ONE WAVE MOVING ACROSS THE AREA THIS EVENING. QUITE A BIT OF DRY AIR TO OVERCOME AND THUS WILL KEEP OUT ANY POPS. ALTHOUGH THERE COULD BE SOME FLURRIES THAT MAKE IT THROUGH THE DRY AIR ACROSS PORTIONS OF SOUTHWEST MINNESOTA AND NORTHWEST IOWA THROUGH THE EVENING HOURS. OTHER QUESTION TONIGHT IS WHETHER WE SEE ANY LOW STRATUS FORM. NAM..GFS...HRRR AND RAP ALL SHOW A PRETTY STRONG SIGNAL...AS LOW LEVEL MOIST AIR IS ADVECTED NORTH INTO OUR COLD AIRMASS. HOWEVER NOTHING OUT THERE RIGHT NOW...AND THE GEM AND ECMWF SEEM A LITTLE LESS AGGRESSIVE ON THE STRATUS. THIS WILL HAVE A BIG IMPACT ON TEMPERATURES TONIGHT. INITIALLY TEMPERATURES WILL BE NEARLY STEADY AS THE SOUTHERLY BREEZE AND MID LEVEL CLOUDS HELP KEEP THINGS MIXED. HOWEVER WINDS WILL LIGHTEN AND MID LEVEL CLOUDS WILL EXIT LATER TONIGHT. IF STRATUS IS NOT AROUND OR EXITS...COULD SEE SOME SUB ZERO TEMPERATURES BY MORNING. HOWEVER IF STRATUS STICKS AROUND READINGS WOULD BE STUCK IN THE SINGLE DIGITS AND TEENS ABOVE ZERO. FOR NOW WILL GO THE MIDDLE GROUND...SINCE CONFIDENCE IS PRETTY LOW ON WHICH SOLUTION WILL VERIFY. TOMORROW WILL BE A MOSTLY CLOUDY DAY WITH THE SLOW WARMING TREND CONTINUING...WITH HIGHS IN THE TEENS AND 20S AND AN EASTERLY WIND AROUND 10 MPH. ANOTHER WAVE IN THE NORTHWEST FLOW WILL MOVE ACROSS THE AREA DURING THE AFTERNOON HOURS. PRETTY GOOD ISENTROPIC LIFT AHEAD OF THE WAVE WILL BEING A BROAD AREA OF LIFT ACROSS THE REGION. THUS LOOKS PRETTY LIKELY THAT WE WILL SEE AN AREA OF SNOW AFTER WE SATURATE THE INITIALLY DRY LOW AND MID LEVELS. CURRENT THOUGHT IS THAT WE WILL SEE AN AREA OF SNOW FORM ACROSS NORTH DAKOTA AS THE WAVE INTERACTS WITH THE MID LEVEL FRONTAL BOUNDARY. THIS WILL THEN MOVE SOUTHEAST INTO OUR AREA...MAINLY DURING THE AFTERNOON HOURS. BEST CHANCE ALONG AND NORTHEAST OF A HURON TO SIOUX FALLS TO SPENCER IOWA LINE...CLOSER TO THE BETTER PV ADVECTION AND FRONTAL BOUNDARY INTERACTION. 12Z NAM SEEMED TOO SLOW AND THUS WAS NOT USED...WITH A BLEND OF THE GFS...GEM AND ECMWF SEEMING LIKE THE WAY TO GO. GIVEN THE PERIOD OF PRETTY GOOD OMEGA...THE HIGHER QPF OF THE HI RES MODELS AND GEM DOES SEEM POSSIBLE. SO DID TREND QPF UP ACROSS SOUTHWEST MINNESOTA. THE 18Z NAM HAS ACTUALLY TRENDED TOWARDS THE OTHER MODELS...AND NOW MATCHES THE FORECAST PRETTY WELL. THINKING WE SEE AN AREA OF 1 TO 3 INCHES SOMEWHERE WITH THIS SYSTEM...WITH THE CURRENT BEST GUESS BEING ACROSS OUR SOUTHWEST MINNESOTA COUNTIES...WITH GENERALLY UNDER AN INCH ELSEWHERE. MODELS TODAY HAVE TRENDED SLIGHTLY SOUTHWEST WITH QPF INTO THE AREA OF BETTER ISENTROPIC LIFT...SO WILL NEED TO MONITOR MODEL AND RADAR TRENDS OVERNIGHT INTO TOMORROW TO SEE EXACTLY WHERE THESE SLIGHTLY HIGHER AMOUNTS WILL FALL. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 334 PM CST MON MAR 3 2014 SHORTWAVE EXITS THE AREA TUESDAY EVENING...ALLOWING THE LIGHT SNOWFALL LINGERING ACROSS OUR EASTERN HALF TO COME TO AN END BY AROUND MIDNIGHT. STRATUS WILL CONTINUE TO BLANKET THE AREA THROUGH THE OVERNIGHT HOURS...KEEPING PREVENTING OVERNIGHT TEMPERATURES FROM DROPPING MUCH FROM DAYTIME HIGHS. LIGHT WINDS SWING AROUND TO THE SOUTH ON WEDNESDAY...SETTING UP WARM AIR ADVECTION INTO THURSDAY. MOSTLY CLOUDY SKIES WILL PUT A CAP ON THE WARMING ON WEDNESDAY... HOWEVER HIGHS SHOULD MANAGE TO REACH THE 20S WITH SOME LOW 30S IN SOUTH CENTRAL SD WHERE A BIT MORE SUNSHINE IS EXPECTED. SOUTHERLY WINDS INCREASE WEDNESDAY NIGHT AND THURSDAY FURTHER BOLSTERING READINGS DESPITE THE POTENTIAL FOR PERSISTENT STRATUS ACROSS THE BULK OF THE FORECAST AREA. HIGHS WILL BE IN THE 30S TO LOWER 40S. SHORTWAVE DROPS SOUTHEAST ACROSS THE AREA LATE THURSDAY NIGHT INTO FRIDAY. ECMWF IS SLIGHTLY SLOWER IN TIMING THAN THE GEM AND GFS...BUT ALL MODELS DO TRACK THE BETTER MOISTURE AND DYNAMICS NORTHEAST OF THE FORECAST AREA. THE BETTER POTENTIAL FOR SEEING ANY LIGHT PRECIPITATION IS ACROSS OUR EASTERN HALF...BUT EVEN HERE MID LEVELS REMAIN PRETTY DRY. WILL LEAVE ONLY MENTION OF A SLIGHT CHANCE OF LIGHT SNOW...BUT MAY NEED TO WATCH FOR THE POTENTIAL FOR A WINTRY MIX WITH FAIRLY MILD MID/LOW LEVELS AND SUB FREEZING AT THE SURFACE. THE WARMING TREND RESUMES SATURDAY INTO EARLY NEXT WEEK WITH RIDGING BUILDING BACK INTO THE HIGH PLAINS FOLLOWED BY QUASI-ZONAL FLOW. DRY WEATHER IS EXPECTED DURING THIS PERIOD WITH HIGHS IN THE 40S AND LOW TO MID 50S SUNDAY AND MONDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1140 AM CST MON MAR 3 2014 VFR CONDITIONS WILL CONTINUE EARLY THIS AFTERNOON. CONFIDENCE LATER THIS AFTERNOON INTO TOMORROW MORNING IS LOW. WILL KEEP THE MVFR CIGS IN THE TAFS AT ALL THREE SITES...AS INDICATIONS FROM THE NAM...GFS AND RAP ARE THAT AS MOISTURE CONTINUES TO INCREASE IN THE SOUTEHRLY FLOW...STRATUS SHOULD DEVELOP. IF IT DOES FORM IT MAY TEND TO LINGER INTO TOMORROW...AS FLOW WEAKENS LEAVING THE MOISTURE OVER US. THIS TYPE OF WINTER TIME STRATUS IS TOUGH TO PREDICT...AND SOMETIMES MODELS OVERDO IT...SO FUTURE SHIFTS WILL NEED TO MONITOR TRENDS AND ADJUST TAFS AS NEEDED. ANOTHER SYSTEM WILL BRING SOME LIGHT SNOW TO THE AREA TOMORROW...BEST CHANCE NORTH OF INTERSTATE 90. MOST OF THIS SHOULD FALL AFTER 18Z...SO WILL KEEP OUT OF THIS TAF ISSUANCE. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM... LONG TERM... AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1146 AM CST MON MAR 3 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 316 AM CST MON MAR 3 2014 DECIDED TO GO AHEAD AND CANCEL THE WIND CHILL ADVISORY FOR SOUTHWEST MN AND THE EASTERN SECTION OF EAST CENTRAL SD EARLY TODAY. THIS IS BECAUSE MID LEVEL CLOUDS HAVE MOVED INTO THAT AREA AND WILL LIKELY NOT EXIT ANYTIME SOON...KEEPING TEMPERATURES MODERATED. IN ADDITION...THE SURFACE RIDGE IS BEGINNING TO ENCROACH INTO OUR EASTERN ZONES KEEPING WINDS LIGHT. NORTHWEST IA AND THE SIOUX FALLS AREA IS ALSO MARGINAL IN KEEPING THE WIND CHILL ADVISORY GOING. HOWEVER DECIDED TO LEAVE IT AS IS FOR NOW AS THE MID LEVEL CLOUDS MAY NOT MAKE IT INTO NORTHWEST IA. IF THEY DO...WILL LIKELY BE ABLE TO CANCEL THOSE AREAS EARLY ALSO BY SUNRISE. OUR WESTERN ZONES HAVE A BIT MORE WIND DUE TO THE RETURN FLOW. OTHERWISE A WEAK SHORT WAVE WILL BE MOVING EASTWARD TODAY...PRIMARILY AFFECTING AREAS NORTH OF OUR FORECAST AREA. INSTEAD OF A SMALL MEASURABLE POP...OPTED TO JUST MENTION FLURRIES FOR OUR FAR NORTHERN ZONES AND SOUTHWEST MN LATE THIS AFTERNOON AND TONIGHT. BOTH THE NAM AND GFS PAINT SOME STRATUS POTENTIAL WITH THIS WAVE LATER TODAY AND TONIGHT IN THOSE AREAS... COUPLED WITH A FAVORABLE THERMAL PROFILE OF -12C TO -18C IN THE STRATUS LAYER. IF THE MODELS ARE OVER ZEALOUS IN DEVELOPING THE STRATUS...THEN EVEN FLURRIES WILL LIKELY NOT OCCUR AS THE NEXT CLOUD DECK IS UP IN THE MID LEVELS. THE RETURN FLOW WILL MODERATE OUR HIGHS TODAY WHEN COMPARED TO THE LAST COUPLE OF DAYS...BUT STILL WAY BELOW NORMAL. COUPLED WITH THE INCREASING WINDS FROM THE SOUTH TO SOUTHEAST...IT STILL WILL NOT FEEL VERY GOOD. TONIGHT...MODERATED AIR WILL BE AROUND. THE OVERALL AIR MASS AT 925MB IS SUBSTANTIALLY WARMER WHEN COMPARED TO RIGHT NOW. IN ADDITION...IT APPEARS CLOUDS WILL CONTINUE TO LINGER EITHER IN THE FORM OF STRATUS FOR MOST LOCATIONS...OR A MID TO UPPER CLOUD DECK. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 316 AM CST MON MAR 3 2014 THE TUESDAY SHORT WAVE WHICH COULD PRODUCE SOME LIGHT SNOW MAINLY OVER OUR NORTHEASTERN FORECAST AREA IS A LITTLE TRICKY. FIRST ON TIMING...THE 00Z NAM FOR SOME REASON DELAYS THE ARRIVAL AND DEPARTURES OF THIS SYSTEM QUITE A BIT AND SEEMS OUT OF LINE WITH THE OTHER MODELS...INCLUDING THE OPERATIONAL NAM...GEM...AND GFS. OUR EARLIER FORECAST FITS WITH THESE OTHER MODELS FAIRLY WELL SO WILL REJECT THE NAM TIMING. ALSO...THIS POTENTIAL LITTLE EVENT SEEMS TO BE DRIVEN MORE BY THE WAVE DYNAMICS THAN ANY SHARP THERMAL GRADIENT UNLIKE SOME OF OUR OTHER RECENT SYSTEMS...SO THERE IS SOME UNCERTAINTY ON AMOUNTS. SINCE THE GFS STILL PRODUCES AMPLE LIFT...WILL KEEP THE IDEA OF AN INCH PLUS IN OUR NORTHEAST CORNER...PART OF SOUTHWEST MN...WITH MOST OF THE PRECIPITATION THREAT TUESDAY AFTERNOON...AND WILL GO WITH LIKELY POPS IN THAT AREA. SOME MINOR APPARENT COOLING AS THIS WAVE PASSES BY WILL MANIFEST ITSELF IN ONLY A LITTLE SLOWDOWN OF SURFACE WARMING AS THE MIXING PROCESS TAKES CARE OF THE CURRENTLY ANCHORED LOW LEVEL ARCTIC AIR. SNOWFALL OR NOT...IT LOOKS LIKE LOW CLOUDS WILL DEVELOP/SPREAD OVER THE AREA WITH AND BEHIND THIS SYSTEM. THESE SHOULD HOLD IN TUESDAY NIGHT...THEN DECREASE SLOWLY FROM THE WEST WEDNESDAY AS SLOW DRYING ACCOMPANIES THE DEVELOPMENT OF THE NEXT WARM ADVECTION EPISODE. THIS WILL SET UP A PATTERN OF PARTLY CLOUDY SOUTHWEST TO MOSTLY CLOUDY NORTHEAST DURING A DRY AND MILDER WEDNESDAY NIGHT AND THURSDAY...WITH TEMPERATURES THURSDAY WARMING TO THE 30S NORTH AND EAST TO THE 40S SOUTHWEST. THIS WILL BEGIN TO MELT SOME OF THE SNOW COVER. FRIDAY WILL BRING SOMEWHAT COOLER TEMPERATURES...ALONG WITH SOME CHANCE OF LIGHT SNOW...AS SOME HALF DECENT THERMAL PACKING IS BRIEFLY DRIVEN BACK SOUTH/SOUTHWEST OVER THE AREA...AND WEAK SHORT WAVE PASSES. RIDGING THEN WILL BRING THE START OF WARMING FROM THE WEST BY SATURDAY AFTERNOON...WHICH APPEARS TO INCREASE STRONGLY FOR SUNDAY. THIS SHOULD WARM TEMPERATURES INTO THE 30S NORTHEAST TO LOWER 50S SOUTHWEST...AND DO SOME SERIOUS MARCH SNOWMELT. THE EC SEEMS TOO STRONG ON THE WARMING...BUT THE GFS HAS PICKED UP SOME ON IT...SO IF THE TREND CONTINUES AND IF THE EC IS CLOSE...WE COULD BE TOO WEAK ON THE SUNDAY WARMUP...BUT AM NOT GETTING THE GOLF CLUBS OUT QUITE YET. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1140 AM CST MON MAR 3 2014 VFR CONDITIONS WILL CONTINUE EARLY THIS AFTERNOON. CONFIDENCE LATER THIS AFTERNOON INTO TOMORROW MORNING IS LOW. WILL KEEP THE MVFR CIGS IN THE TAFS AT ALL THREE SITES...AS INDICATIONS FROM THE NAM...GFS AND RAP ARE THAT AS MOISTURE CONTINUES TO INCREASE IN THE SOUTEHRLY FLOW...STRATUS SHOULD DEVELOP. IF IT DOES FORM IT MAY TEND TO LINGER INTO TOMORROW...AS FLOW WEAKENS LEAVING THE MOISTURE OVER US. THIS TYPE OF WINTER TIME STRATUS IS TOUGH TO PREDICT...AND SOMETIMES MODELS OVERDO IT...SO FUTURE SHIFTS WILL NEED TO MONITOR TRENDS AND ADJUST TAFS AS NEEDED. ANOTHER SYSTEM WILL BRING SOME LIGHT SNOW TO THE AREA TOMORROW...BEST CHANCE NORTH OF INTERSTATE 90. MOST OF THIS SHOULD FALL AFTER 18Z...SO WILL KEEP OUT OF THIS TAF ISSUANCE. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM...MJ LONG TERM... AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS SPOKANE WA
251 PM PST Mon Mar 3 2014 .SYNOPSIS... A much warmer and wetter weather pattern will arrive this week with several several moist frontal systems expected. Look for widespread rain Wednesday and Thursday, and again Saturday night into Sunday. The combination of rain and melting snow will heighten the potential for minor flooding of farm land and urban areas that have problems with drainage. By the weekend, several rivers in the Idaho Panhandle and southeast Washington may experience significant rises. && .DISCUSSION... ...MAJOR PATTERN CHANGE TO BRING RAIN...WARMER TEMPERATURES...AND THE POTENTIAL FOR FLOODING STARTING WEDNESDAY... Tonight: As the frontal band pushes through north Idaho and into Montana, the threat for wintry precipitation will be decreasing. Expect upslope mountain snow showers over the Idaho panhandle, but additional snow accumulations should be minor. Meanwhile snow showers will continue near the Cascade crest, but again these slop- over snow showers are not expected to be significant under this unstable westerly flow. Temperatures will creep above freezing south of a line from Moses Lake to Spokane and Coeur d`Alene early this evening, but then cool slightly overnight back to freezing. This may cause some icy problems with the overnight cool early Tuesday morning. Under this warmer regime and light winds during the overnight hours, expect area of fog and low stratus especially in many of the northern valleys and upper Columbia Basin tonight. /rfox. Tuesday through Thursday: Satellite imagery shows a moist subtropical moisture plume originating off the Hawaiian Islands and pointed toward the western U.S. This moisture plume is expected to be directed toward the region as a couple of shortwave disturbances push across the region. The first wave is expected to hit Wednesday morning into Wednesday afternoon. This wave will essentially push across as a warm front with moist isentropic lift across much of the region. The second and stronger disturbance will push in quickly on the heals of the first. This shortwave will be accompanied by some good dynamics aloft with strong isentropic ascent in the warm sector before a cold front passes through around the morning hours on Thursday. Southerly winds will increase during the overnight hours on Wednesday with windy conditions possible by Thursday morning into the afternoon behind the cold front. * Precipitation and Snow Levels: Most areas are expected to see valley rain and mountain snow with these two weather systems. The one caveat will be in the upper reaches of the Methow Valley over into the Okanogan Highlands. Snow levels may remain low enough that locations such as Mazama, Winthrop and Republic will start out as snow Wednesday morning before transitioning over to rain through Wednesday afternoon. Snow accumulations in these valleys are expected to be light in the range of 1 to 3 inches. Precip amounts with the two systems will be moderate to heavy in places. The east slopes of the Cascades are expected to see around a half an inch to an inch with closer to 1.5 to 2 inches along the crest. The Okanogan Highlands over to the Northern Panhandle and into the Central Panhandle Mtns are expected to see precip totals of between a half an inch to 1 inch total; local accumulations of over an inch of precip will be possible over a 36 hour period. Rainfall accumulations of around a half an inch will be possible across the eastern portions of the Upper Columbia Basin, into the Spokane Coeur d`Alene area and down onto the Palouse. Heavy mountain snowfall will be possible in the mountains above 4500 feet in the northern mtns and 5500 feet in the Central Panhandle Mtns. * Temperatures: Milder air under southwesterly flow is expected during this period. Expect temps warming into the 40s and 50s by Thursday. Wednesday night`s low temps will also be quite mild with dew point temps in the mid to upper 30s for much of the region. Dew point temps above freezing will add to proficiency of melting snow at low and mid elevations. * Flood Potential: The combination of warming temps and moderate to heavy rain will result in rises to area rivers and small streams. Flood is not expected on main stem rivers at this time. The greatest threat will be for flooding along small stream and creeks, urban area flooding and mud slides/debris flows. Valley snowfall of 4 to 8 inches in places and frozen soils will heighten the potential for flooding. A Flood Watch will be issued for portions of the Upper Columbia Basin, the Spokane Area, the northern mountain areas of eastern WA and in the ID Panhandle for Tuesday night through Friday afternoon. * Winds: Breezy conditions are expected on Thursday with winds up to 20 to 25 mph and gusts as high as 35 mph across the basin. /SVH Thursday Night through Saturday: There is good model agreement that rain and mountain snow will be winding down Thursday night into early Friday morning. Modest cool advection Thursday night behind the cold front will likely push snow levels down into the 3000-4000 ft range across the Inland Northwest. At this time, we are not looking for snow accumulations in the valleys. The good news with the falling snow levels will be a bit of a decrease in the rate of snow melt in the mid elevations Thursday night into Friday. Travel over the mountain passes, especially above 4000 feet may become slushy and treacherous Thursday night into Friday morning. A shortwave ridge Friday and Friday night should bring a break in the active weather pattern. Orographic rain and mountain snow showers over the Idaho Panhandle will be mostly a morning event on Friday if the ECMWF, GFS and Canadian models hold true. The next mild, breezy, and wet frontal system should arrive Saturday night into Sunday. There is very good model agreement leading higher than average forecast confidence for the weekend forecast. /GKoch Sunday and Monday: A strong push of moisture will continue to pass through the region. This will keep chances for precip across the Inland Northwest high. Warm southerly flow will continue to impact the region. The warmer temperatures will push the snow levels to the higher elevations of the mountains and most places can expect to see rain showers. By late Sunday into early Monday, a weak ridge will creep into the region and start a drying trend and decreasing precipitation chances in the region. Temperatures are expected to remain around the season normals. /JDC && .AVIATION... 18Z TAFS: Mixed precipitation will effect KEAT, KMWH, KGEG and KCOE through 21z as a warm front lifts northward. Based on recent ACCRS data, the warm layer is deepening and should help to scrub out the boundary layer cold layer this afternoon at these sites. KPUW and KLWS will see occasional rain. HRRR data shows not much precipitation after this band pulls through after 00z, with just valley rain/mountain snow. Local MVFR cigs are possible with area of stratus and fog. rfox. && .PRELIMINARY POINT TEMPS/POPS... Spokane 32 43 34 44 39 48 / 30 40 40 100 100 80 Coeur d`Alene 32 41 34 43 37 46 / 40 50 50 100 100 80 Pullman 36 43 35 45 40 49 / 40 50 50 90 100 80 Lewiston 38 46 38 50 42 53 / 50 40 40 60 90 70 Colville 31 43 34 44 35 50 / 40 40 50 100 100 80 Sandpoint 31 40 33 41 36 46 / 70 80 70 100 100 100 Kellogg 33 38 33 42 37 44 / 100 100 70 100 100 100 Moses Lake 31 44 33 52 43 57 / 20 10 20 80 90 30 Wenatchee 30 41 33 49 39 52 / 20 10 20 80 100 30 Omak 29 41 29 45 35 50 / 20 20 10 100 90 40 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...Flood Watch from Tuesday afternoon through Friday morning for Central Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-Northern Panhandle. Winter Storm Warning until 4 PM PST this afternoon for Northern Panhandle. WA...Flood Watch from Tuesday afternoon through Friday morning for Northeast Mountains-Okanogan Highlands-Spokane Area-Upper Columbia Basin-Washington Palouse. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
211 PM PST Mon Mar 3 2014 .SYNOPSIS... A very moist series of storms will move through the Pacific Northwest through Thursday. Each storm will be warmer than the last with snow turning to rain at most locations except the higher mountains between Today and Thursday. A brief break period at the end of the week will be followed by more wet weather this weekend. && .DISCUSSION... Band of mixed precipitation has moved into north Idaho and the Palouse...which brings an end to the freezing rain to the Spokane area and the upper Columbia Basin and northeast Washington mountains. Still have a winter highlight for Idaho zone 1, but that will end as the passage of the front late this afternoon. Meanwhile, snow shower will continue near the crest, but accumulations are expected to dwindle on the lower slopes so took down the highlight for the east slopes of the Cascades. /rfox. && .AVIATION... 18Z TAFS: Mixed precipitation will effect KEAT, KMWH, KGEG and KCOE through 21z as a warm front lifts northward. Based on recent ACCRS data, the warm layer is deepening and should help to scrub out the boundary layer cold layer this afternoon at these sites. KPUW and KLWS will see occasional rain. HRRR data shows not much precipitation after this band pulls through after 00z, with just valley rain/mountain snow. Local MVFR cigs are possible with area of stratus and fog. rfox. && .PRELIMINARY POINT TEMPS/POPS... Spokane 36 32 43 34 44 39 / 50 30 40 40 100 100 Coeur d`Alene 35 32 41 34 43 37 / 60 40 50 50 100 100 Pullman 41 36 43 35 45 40 / 50 40 50 50 90 100 Lewiston 44 38 46 38 50 42 / 50 50 40 40 60 90 Colville 32 31 43 34 44 35 / 30 40 40 50 100 100 Sandpoint 31 31 40 33 41 36 / 70 70 80 70 100 100 Kellogg 36 33 38 33 42 37 / 90 100 100 70 100 100 Moses Lake 34 31 44 33 52 43 / 20 20 10 20 80 90 Wenatchee 31 30 41 33 49 39 / 30 20 10 20 80 100 Omak 32 29 41 29 45 35 / 20 20 20 10 100 90 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...Flood Watch from Tuesday afternoon through Friday morning for Central Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-Northern Panhandle. Winter Storm Warning until 4 PM PST this afternoon for Northern Panhandle. WA...Flood Watch from Tuesday afternoon through Friday morning for Northeast Mountains-Okanogan Highlands-Spokane Area-Upper Columbia Basin-Washington Palouse. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1208 PM PST Mon Mar 3 2014 .SYNOPSIS... A very moist series of storms will move through the Pacific Northwest through Thursday. Each storm will be warmer than the last with snow turning to rain at most locations except the higher mountains between Today and Thursday. A brief break period at the end of the week will be followed by more wet weather this weekend. && .DISCUSSION... Was able to take down a few highlights, based on both radar trends and temperatures. The main brunt of the precipitation has exited the Wenatchee area and Waterville Plateau where the threat for mixed precipitation is low anyway due to the cold air damning. The Moses Lake area is still below freezing, but main band has shifted to the east and only expect isolated to scattered showers. Meanwhile, the Coeur d`Alene area and the Central panhandle have warmed considerable with snow levels up to Lookout Pass and threat for freezing rain very low. So will extend the advisory until 2 pm for the Upper Columbia Basin and Spokane area where temperatures are near freezing and precipitation heavy to moderate. Also extended the winter storm warning for the Northeast Washington mountains and north Idaho until 4 pm, as will the east slopes of the Cascades. /rfox. && .AVIATION... 18Z TAFS: Mixed precipitation will effect KEAT, KMWH, KGEG and KCOE through 21z as a warm front lifts northward. Based on recent ACCRS data, the warm layer is deepening and should help to scrub out the boundary layer cold layer this afternoon at these sites. KPUW and KLWS will see occasional rain. HRRR data shows not much precipitation after this band pulls through after 00z, with just valley rain/mountain snow. Local MVFR cigs are possible with area of stratus and fog. rfox. && .PRELIMINARY POINT TEMPS/POPS... Spokane 36 33 44 34 45 41 / 100 50 40 40 100 100 Coeur d`Alene 35 32 43 33 44 39 / 100 50 50 50 100 100 Pullman 41 36 46 36 49 42 / 70 50 50 50 90 100 Lewiston 44 38 52 40 54 44 / 70 50 40 40 60 90 Colville 32 31 45 31 45 36 / 100 50 40 50 100 100 Sandpoint 31 31 41 32 42 37 / 100 80 80 70 100 100 Kellogg 36 33 40 34 43 39 / 100 80 100 70 100 100 Moses Lake 34 32 52 35 52 44 / 50 20 10 20 80 90 Wenatchee 31 31 47 35 49 40 / 50 20 10 20 80 100 Omak 32 30 46 31 46 37 / 60 30 20 10 100 90 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...Winter Storm Warning until 4 PM PST this afternoon for Northern Panhandle. WA...Winter Storm Warning until 4 PM PST this afternoon for East Slopes Northern Cascades-Northeast Mountains. Winter Weather Advisory until 2 PM PST this afternoon for Spokane Area-Upper Columbia Basin. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
940 AM PST Mon Mar 3 2014 .SYNOPSIS... A very moist series of storms will move through the Pacific Northwest through Thursday. Each storm will be warmer than the last with snow turning to rain at most locations except the higher mountains between Today and Thursday. A brief break period at the end of the week will be followed by more wet weather this weekend. && .DISCUSSION... Next band of precipitation quickly pushing across eastern Washington. Main concern is the low level temp profile. A warm front spans from near KALW, northeast toward Escure, Cheney, and Harrison with a bubble of above freezing air to the south. Along and northwest of this boundary, expect a wintry mix. Latest KMWH obs shows freezing rain and this should reach impact I-90 to the Spokane area through 10 am. The warm air will work its way to the ground through midday with a transistion to rain expected across the lower Basin and Spokane area. Although, the HRRR shows the main brunt of the precipitation leaving the Basin after 21z, and the Spokane/Coeur d`Alene area after 23z. rfox. && .AVIATION... 18Z TAFS: Mixed precipitation will effect KEAT, KMWH, KGEG and KCOE through 21z as a warm front lifts northward. Based on recent ACCRS data, the warm layer is deepening and should help to scrub out the boundary layer cold layer this afternoon at these sites. KPUW and KLWS will see occasional rain. HRRR data shows not much precipitation after this band pulls through after 00z, with just valley rain/mountain snow. Local MVFR cigs are possible with area of stratus and fog. rfox. && .PRELIMINARY POINT TEMPS/POPS... Spokane 36 33 44 34 45 41 / 90 60 50 30 100 100 Coeur d`Alene 35 32 43 33 44 39 / 90 70 60 50 100 100 Pullman 42 36 46 36 49 42 / 80 70 70 50 80 90 Lewiston 44 39 52 40 54 44 / 80 60 60 40 60 90 Colville 34 31 45 31 45 36 / 90 70 50 30 100 100 Sandpoint 31 31 41 32 42 37 / 100 70 70 60 100 100 Kellogg 36 33 40 34 43 39 / 100 90 100 70 100 100 Moses Lake 37 34 52 35 52 44 / 60 30 20 20 80 90 Wenatchee 34 33 47 35 49 40 / 60 30 20 10 80 90 Omak 33 30 46 31 46 37 / 70 30 20 10 100 100 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...Winter Weather Advisory until Noon PST today for Coeur d`Alene Area. Winter Storm Warning until Noon PST today for Central Panhandle Mountains-Northern Panhandle. WA...Winter Weather Advisory until Noon PST today for Moses Lake Area- Spokane Area-Upper Columbia Basin-Waterville Plateau- Wenatchee Area. Winter Storm Warning until Noon PST today for Northeast Mountains. Winter Storm Warning until 4 PM PST this afternoon for East Slopes Northern Cascades. && $$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
854 AM PST Mon Mar 3 2014 .SYNOPSIS... A very moist series of storms will move through the Pacific Northwest through Thursday. Each storm will be warmer than the last with snow turning to rain at most locations except the higher mountains between Today and Thursday. A brief break period at the end of the week will be followed by more wet weather this weekend. && .DISCUSSION... Next band of precipitation quickly pushing across eastern Washington. Main concern is the low level temp profile. A warm front spans from near KALW, northeast toward Escure, Cheney, and Harrison with a bubble of above freezing air to the south. Along and northwest of this boundary, expect a wintry mix. Latest KMWH obs shows freezing rain and this should reach impact I-90 to the Spokane area through 10 am. The warm air will work its way to the ground through midday with a transistion to rain expected across the lower Basin and Spokane area. Although, the HRRR shows the main brunt of the precipitation leaving the Basin after 21z, and the Spokane/Coeur d`Alene area after 23z. rfox. && .AVIATION... 12Z TAFS: A warm front laying from KELN to KMLP at 12Z will move north today in response to a disturbance moving up from Oregon. This warm front passage will bring a mix of precipitation with MVFR and IFR ceilings common at most TAF sites today. A short period of FZRA is likely at the KGEG area TAF sites probably between 17Z and 20Z before surface temperatures rise above freezing. The FZRA threat will be longer duration at KMWH and KEAT where cold near surface air is deeper...but precipitation will be spottier and intermittent with a partial rain shadow provided by the Cascades. KPUW and KLWS are already above freezing this morning and will remain so through the TAF period for mainly RA with MVFR or low VFR ceilings. The storm system will move out of the region tonight...but a warmer low level air mass and melting snow will promote areas of fog and stratus after 06Z tonight. /MJF && .PRELIMINARY POINT TEMPS/POPS... Spokane 36 33 44 34 45 41 / 90 60 50 30 100 100 Coeur d`Alene 35 32 43 33 44 39 / 90 70 60 50 100 100 Pullman 42 36 46 36 49 42 / 80 70 70 50 80 90 Lewiston 44 39 52 40 54 44 / 80 60 60 40 60 90 Colville 34 31 45 31 45 36 / 90 70 50 30 100 100 Sandpoint 31 31 41 32 42 37 / 100 70 70 60 100 100 Kellogg 36 33 40 34 43 39 / 100 90 100 70 100 100 Moses Lake 37 34 52 35 52 44 / 60 30 20 20 80 90 Wenatchee 34 33 47 35 49 40 / 60 30 20 10 80 90 Omak 33 30 46 31 46 37 / 70 30 20 10 100 100 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...Winter Weather Advisory until Noon PST today for Coeur d`Alene Area. Winter Storm Warning until Noon PST today for Central Panhandle Mountains-Northern Panhandle. WA...Winter Weather Advisory until Noon PST today for Moses Lake Area- Spokane Area-Upper Columbia Basin-Waterville Plateau- Wenatchee Area. Winter Storm Warning until Noon PST today for Northeast Mountains. Winter Storm Warning until 4 PM PST this afternoon for East Slopes Northern Cascades. && $$
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND TUESDAY ISSUED AT 212 PM CST MON MAR 3 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH PRESSURE STRETCHING FROM TEXAS TO THE CENTRAL GREAT LAKES EARLY THIS AFTERNOON. CLOUDS ARE INCREASING FROM WEST TO EAST ACROSS THE STATE AHEAD OF SHORTWAVES MOVING ACROSS THE DAKOTAS. THE LEADING EDGE OF A BAND OF SNOW IS ALREADY APPROACHING NORTHWEST WISCONSIN ALONG A MID-LEVEL FGEN/WARM ADVECTION ZONE. DISTANCE/SPEED TOOL HAS THIS BAND OF SNOW MOVING INTO NORTH-CENTRAL WISCONSIN BETWEEN 23-00Z THIS AFTERNOON. AS THE SNOW MOVES TO THE SOUTHEAST...SNOW TIMING AND AMOUNTS ARE THE MAIN FORECAST CONCERNS. TONIGHT...WEAK SHORTWAVE ENERGY OVER THE DAKOTAS WILL MOVE ESE TO THE NORTHERN MISSISSIPPI VALLEY THIS EVENING AND REACH LAKE MICHIGAN BY 12Z TUESDAY. AHEAD OF THE WAVES...FORCING IN THE FORM OF ISENTROPIC ASCENT...700-500MB FGEN AND WEAK UPPER DIVERGENCE WILL PUSH THE AREA OF SNOW OVER EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA ACROSS NORTHERN WISCONSIN THIS EVENING. UNCERTAINTY REMAINS HOW THIS WILL EVOLVE...BUT SOME MODELS SHOW A SECONDARY AREA OF SNOW MAY ALSO DEVELOP OVER SOUTHERN MINNESOTA/NORTHERN IOWA THIS EVENING ALONG THE LOW LEVEL BAROCLINIC ZONE AND THEN MERGE WITH THE PRIMARY AREA OF SNOW OVER CENTRAL AND EASTERN WISCONSIN. AS A RESULT...THINK ALL AREAS WILL SEE DECENT ACCUMULATING SNOW TONIGHT THOUGH PIN POINTING WHERE AND HOW MUCH SNOW WILL FALL IS RATHER DIFFICULT DUE TO THE UNORGANIZED FORCING. ADDING TO THE COMPLEXITY IS A DEEP DENDRITIC GROWTH ZONE THAT COULD LEAD TO HIGH END SNOW TO LIQUID RATIOS. BEST GUESS IS NOT THAT DIFFERENT FROM THE PREVIOUS SHIFT...FROM TOMAHAWK TO STURGEON BAY WHERE HAVE ABOUT 2 INCHES IN THE FORECAST THROUGH TONIGHT. THE SNOW WILL BE LIGHT AND FLUFFY...AND BE WINDING DOWN TOWARDS THE START OF THE MORNING COMMUTE...SO DO NOT PLAN ON ANY ADVISORIES. BUT WILL ISSUE AN SPS TO HIGHLIGHT SLICK ROADS TONIGHT AND EARLY TOMORROW MORNING. TUESDAY...LIGHT SNOW WILL BE ONGOING OVER MUCH OF THE FORECAST EARLY TUESDAY MORNING UNTIL THE SHORTWAVE EXITS TO THE EAST. BUT EVEN AFTER THIS TIME...THE MID-LEVEL THERMAL GRADIENT WILL BE OVERHEAD AND PROGGED SOUNDINGS INDICATE PLENTY OF MOISTURE WILL BE LEFTOVER THROUGH 700-600MB UNTIL MID TO LATE AFTERNOON. SO DESPITE THE SHORTWAVES PULLING OUT...POTENTIAL IS THERE FOR LIGHT SNOW/FLURRIES TO LINGER INTO THE AFTERNOON. ADDITIONAL ACCUMS WILL REACH UP TO A HALF INCH...AND MUCH OF THAT WILL COME EARLY IN THE MORNING. SKIES WILL BE MAINLY CLOUDY...BUT HIGHS WILL CONTINUE THERE WARMING TREND AND REACH THE UPPER TEENS TO LOWER 20S. .LONG TERM...TUESDAY NIGHT THROUGH MONDAY ISSUED AT 212 PM CST MON MAR 3 2014 CONTINUED NEAR ZONAL-PROGRESSIVE PATTERN OVER THE NORTHERN U.S. THIS PERIOD. SPREAD SEEN IN MODELS/ENSEMBLES LATER PERIODS WITH HOW HANDLE ENERGY COMING INTO PACIFIC COAST AND EFFECTS ON UPPER RIDGE. TRENDS ARE FOR TEMPS TO WARM CLOSER TO NORMS THROUGH PERIOD WITH MORE WESTERLY FLOW. MODEL BLEND FOR NEXT MONDAY SHOWING UPPER 30S ATTM. A REAL CONTRAST FROM TODAY. LIGHT SNOW CHANCES AT ISSUE AGAIN TUE NIGHT AS WEAK WAVE MOVES THROUGH FLOW. WAA SETS UP OVER BAROCLINIC ZONE TO BE CENTERED OVER SOUTHERN HALF OF WI. WEAK FGEN/JET SUPPORT...PASSES MAINLY SOUTH OF CWA. AGAIN MODELS TRENDING TOWARD DEEP DENDRITIC GROWTH ZONE. HAVE TIGHTENED GRADIENT UP FOR SNOW-NO SNOW WITH HIGH PRESSURE RIDGING SOUTH OUT OF CANADA INTO NORTHERN WI. KEPT CHANCE POPS OVER FAR SOUTHERN COUNTIES. NEXT ISSUE WITH UPPER LOW NOW MOVING INTO BRITISH COLUMBIA. FEATURE TO TRACK EAST ACROSS CANADA. MODELS SHOWING A BIT BETTER AGREEMENT WITH FOCUS OF PCPN CHANCES THU OVER NORTHWEST WI AND NORTHEAST MN...MOVING INTO CWA THU NIGHT INTO FRI WITH COLD FRONT MOVING THROUGH STATE. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1135 AM CST MON MAR 3 2014 VFR CONDITIONS WILL HOLD ACROSS THE REGION THROUGH THE END OF THE AFTERNOON. CLOUDS WILL BE INCREASING THOUGH...AHEAD OF A WEAK STORM SYSTEM MOVING OVER THE NORTHERN MISSISSIPPI VALLEY. THIS STORM SYSTEM WILL ARRIVE THIS EVENING...WITH LIGHT SNOW MOVING IN FROM WEST TO EAST DURING THE MID TO LATE EVENING HOURS. IFR CEILINGS AND VISIBILITIES WILL ACCOMPANY THE LIGHT AND FLUFFY SNOW. MOST OF THE SNOW WILL END EARLY TUESDAY MORNING...THOUGH EXPECT FLURRIES AND MVFR CONDITIONS TO CONTINUE THROUGH THE END OF THE TAF PERIOD. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......TE AVIATION.......MPC
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1114 AM CST MON MAR 3 2014 .UPDATE...LAKE EFFECT SNOW BAND CONTINUES TO AFFECT FAR SOUTHEAST WISCONSIN...MAINLY SOUTH OF DOWNTOWN MILWAUKEE TO KENOSHA...AND INTO THE EASTERN AND CENTRAL PORTIONS OF RACINE AND KENOSHA COUNTIES. MODERATE SNOW WITH 1/2 MILE VISIBILITIES SHIFTING INTO OAK CREEK AND SOUTH MILWAUKEE...WITH MORE OFFSHORE TO THE NORTHEAST. THESE WERE SHIFTING WEST AROUND 10 MPH. FAVORABLE DELTA T VALUES...ALONG WITH PROLONGED LOW LEVEL CONVERGENCE AND MOISTURE...HAVE HELPED THIS BAND PERSIST. NONE OF THE MESOSCALE MODELS HAVE A HANDLE ON THIS BAND. SYNOPTIC MODELS AND HRRR DID SHOW SURFACE CONVERGENCE SHIFTING BACK OVER THE WATER AND OUT OF THE AREA BY EARLY THIS AFTERNOON...AROUND 19Z OR SO. WILL KEEP SNOW SHOWERS UNTIL AROUND THAT TIME...THEN TAPER OFF QUICKLY AFTERWARDS. A QUICK 1/2 INCH OF SNOW IS EXPECTED IN ANY OF THE MODERATE SNOW BANDS...WITH LIGHTER ACCUMULATIONS ELSEWHERE IN THIS AREA. THE REST OF THE AREA WILL SEE QUIET WEATHER WITH GRADUALLY INCREASING CLOUDS LATER THIS AFTERNOON. && .AVIATION/18Z TAFS/...LAKE EFFECT SNOW SHOWERS WITH VISIBILITIES AT OR BELOW ALTERNATE MINIMUMS WILL CONTINUE TO AFFECT KENOSHA UNTIL 19Z...AND PERHAPS MILWAUKEE AS WELL. SOME UNCERTAINTY IF SNOW BAND WILL MAKE IT INTO MILWAUKEE. IF IT DOES...A QUICK 1/2 INCH OF SNOW IS POSSIBLE. KENOSHA SHOULD SEE ACCUMULATIONS UP TO 1/2 INCH AS WELL. CEILINGS SHOULD THEN SCATTER OUT BY MID TO LATE AFTERNOON. WINDS WILL BE LIGHT AND VARIABLE...BECOMING WEST LATE IN THE AFTERNOON. WAUKESHA AND MADISON WILL SEE VFR CONDITIONS WITH LIGHT AND VARIABLE WINDS SHIFTING WEST BY LATER THIS AFTERNOON. CEILINGS WILL REMAIN VFR THIS EVENING...AS WINDS BECOME LIGHT AND SOUTHWEST. AREA OF LIGHT SNOW WILL MOVE INTO MADISON AROUND 06Z TUESDAY...AND THE EASTERN SITES BETWEEN 07Z AND 09Z TUESDAY. THE LIGHT SNOW SHOULD LINGER FOR A 4 TO 6 HOUR PERIOD BEFORE ENDING. SNOWFALL RATES WILL BE VERY LIGHT...AROUND 1/10 OF AN INCH PER HOUR. SNOW ACCUMULATIONS UP TO 1/2 INCH ARE EXPECTED. VISITILITIES WILL BE AROUND ALTERNATE MINIMUMS...WITH CEILINGS AROUND OR ABOVE 2000 FEET ABOVE GROUND LEVEL. CEILINGS AND VISIBILITIES WILL IMPROVE TO VFR BY MID MORNING TUESDAY...LINGERING THROUGH THE REST OF THE DAY. WINDS WILL BE LIGHT. && .MARINE...NEARSHORE WATERS REMAINS ICE COVERED...AS WELL AS A GOOD PORTION OF THE OPEN WATERS. THUS...ANY WAVE ACTION WILL BE LIMITED. && .PREV DISCUSSION... /ISSUED 337 AM CST MON MAR 3 2014/ SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH. WINDS HAVE NOT QUITE DECOUPLED AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS SOUTHERN WISCONSIN. WITH CONTINUED FALLING TEMPERATURES THE FAIRLY LIGHT WINDS WILL STILL BRING WIND CHILLS TO 15 TO 25 BELOW. DIMINISHING WINDS SHOULD END ANY WIND CHILL ADVISORY CRITERIA BY 9 AM CST. A MID LEVEL TROUGH WILL MOVE INTO SOUTHERN WISCONSIN LATE TONIGHT. 700 MB WARM AIR ADVECTION OCCURS AHEAD OF THE SHORTWAVE...WHILE 850 MB LEVELS REMAIN RATHER COLD. WEAK TO MODERATE 700 MB UPWARD MOTION...WITH THE STRONGER VALUES ACROSS THE NORTH OF THE FORECAST AREA. 700 MB LAYERS SATURATE...BUT 925 AND 850 MB REMAIN RATHER DRY. CONDENSATION PRESSURE DEFICITS LOWER TO 5 TO 10 MB ON THE 285 AND 290 KELVIN ISENTROPIC LAYERS WITH MODERATE LIFT. WILL THEREFORE MENTION A PERIOD OF LIGHT SNOW WITH HIGHER CHANCES IN THE NORTHEAST TOWARD THE DELLS...FOND DU LAC...AND SHEBOYGAN. AMOUNTS WILL BE LESS THAN AN INCH. SHOULD SEE SOME MIDDLE LEVEL CLOUDS MOVE EAST INTO THE AREA DURING THE AFTERNOON. HIGHS WILL REMAIN WELL BELOW NORMAL...IN THE 10 TO 15 DEGREE FAHRENHEIT RANGE. WITH THICKENING CLOUDS OVERNIGHT...EXPECT A NON DIURNAL TEMPERATURE TREND...WITH A SLOW RISE IN TEMPERATURES TOWARD TUESDAY MORNING. TUESDAY...FORECAST CONFIDENCE MEDIUM. ANY LINGERING LIGHT SNOW WILL TAPER OFF DURING THE MORNING HOURS. MID LEVEL CLOUDS WILL HANG AROUND THROUGH THE DAY WITH CYCLONIC FLOW ALOFT AND MOISTURE IN THE MID LEVELS. ANOTHER WEAK SHORTWAVE TRACKING THROUGH THE UPPER MIDWEST ALONG A BAROCLINIC ZONE SET UP OVER SOUTHERN MN/SOUTHERN WI WILL LIKELY BRING A QUICK-HITTING INCH OF SNOW TO SOUTHERN WI MAINLY TUESDAY EVENING. SNOW WILL TAPER OFF FROM NORTHWEST TO SOUTHEAST LATE TUE NIGHT. CONFIDENCE IS SLOWLY INCREASING WITH THIS SYSTEM...SO INCREASED POPS A LITTLE. THE 00Z NAM WAS A CLEAR OUTLIER WITH QPF FOR THE TUE-WED SYSTEMS...BUT THE 06Z NAM HAS COME INTO AGREEMENT WITH THE 00Z ECMWF AND 00Z GFS MODELS. WEDNESDAY...FORECAST CONFIDENCE MEDIUM. WEDNESDAY...FORECAST CONFIDENCE MEDIUM. LOW LEVEL FLOW BECOMES NORTHEASTERLY WEDNESDAY MORNING AS HIGH PRESSURE SLIDES ACROSS LAKE SUPERIOR. GFS AND ECMWF ARE HANGING ON TO HIGHER 1000-850MB RH THROUGH THE DAY WED. WHILE THE MAIN SYSTEM SNOW WILL HAVE MOVED OFF TO THE SOUTH AND EAST...ANY LOW CLOUDS COULD STILL PRODUCE FLURRIES OVER SOUTHERN WI. LONG TERM... WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE MEDIUM. WEAK HIGH PRESSURE DRIFTING ACROSS THE UPPER MIDWEST WILL ALLOW FOR A DRY PERIOD. RADIATIONAL COOLING LATE WED NIGHT WILL BE POSSIBLE IF CLOUDS CAN CLEAR. OTHERWISE...EXPECT WARMER MIN TEMPS THAN ARE CURRENTLY FORECAST. TEMPS WILL RISE QUICKLY THU WITH INCREASING SOUTHERLY WINDS AND WARM AIR ADVECTION. THURSDAY NIGHT THROUGH SUNDAY...FORECAST CONFIDENCE MEDIUM. A COLD FRONT WILL SLOWLY SAG SOUTHWARD THROUGH WI THU NIGHT THROUGH FRI. THERE ARE SUBTLE DIFFERENCES BETWEEN THE TIMING OF PRECIP OVER SOUTHERN WI...SO TOOK CONSENSUS APPROACH. TEMPS ALOFT AND AT THE GROUND WILL APPROACH OR EVEN RISE JUST ABOVE FREEZING FRI AFTERNOON. THUS KEPT A RAIN/SNOW CHANCE MENTION FOR THAT PERIOD. THE WEATHER LOOKS DRY FOR SATURDAY AFTERNOON THROUGH SUNDAY AT THIS TIME. HOWEVER...THERE SHOULD BE A BAROCLINIC ZONE WITH SNOW SET UP ACROSS NORTHERN IL. A CHANGE IN THE MODELS COULD BRING THE CHANCE OF SNOW BACK INTO SOUTHERN WI. IF SOUTHERN WI WEATHER IS DRY NEXT WEEKEND IT MEANS WE ARE ON THE COLD SIDE OF THE FRONT AND OUR MAX TEMPS WILL BE AT OR JUST BELOW FREEZING. AVIATION/12Z TAFS/... VFR CONDITIONS EXPECTED THROUGH THE EVENING AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS SOUTHERN WISCONSIN. SOME HIGH/MID-LEVEL CLOUDS WILL MOVE IN AHEAD OF AN APPROACHING MID LEVEL TROUGH. LIGHT SNOW EXPECTED TO FALL WITH MVFR CIGS/VSBYS...ESPECIALLY NORTH OF MADISON AND MILWAUKEE AFTER MIDNIGHT. MARINE... NORTHWEST WINDS WILL WEAKEN THIS MORNING AS A RIDGE OF HIGH PRESSURE BUILDS ACROSS SOUTHERN LAKE MICHIGAN. MOST OF THE NEARSHORE WATERS REMAIN ICE COVERED. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...WOOD TODAY/TONIGHT AND AVIATION/MARINE...HENTZ TUESDAY THROUGH SUNDAY...MRC