Aikyam-Lab/Synoptic-Bench huggingface dataset:
1030 PM EDT TUE MAR 17 2015 A WEAK FRONTAL TROUGH LOCATED ACROSS CENT AL/GA WILL PUSH RAPIDLY SOUTH REACHING NORTH LAKE/VOLUSIA COUNTIES TOWARD SUNRISE. LOWS IN THE LOW-MID 60S AREAWIDE.
/ISSUED 242 PM CDT Tue Mar 17 2015/ An upper low is currently moving northward toward southwest Texas from northern Mexico. A cold front is pushing southward through the CWA this afternoon with showers across the area. There is good upper lift associated with the upper low as indicated by the 500 mb omega values and vorticity maximum over the area. High temperatures today are expected to be below normal and about 15 degrees cooler than yesterday across the Permian Basin and southeast New Mexico behind the front. The area of rain and thunderstorms is expected to shift northward overnight tonight as the upper low moves north over the area. The precipitation is expected to decrease in coverage beginning Wednesday morning as the upper low moves northeast of the CWA.
FAIR WEATHER HIGH PRESSURE CURRENTLY OVER THE REGION WILL BE BREAKING DOWN OVER THE NEXT 12-24 24 HOURS. CUT-OFF LOW OVER NORTHERN OLD MEXICO WILL TREK NORTHEAST TRANSITIONING INTO AN OPEN TROF AS IT ADVANCES INTO THE LOWER MISSISSIPPI VALLEY LATE WEDNESDAY NIGHT.
THIS EVENING THROUGH WEDNESDAY NIGHT STALLED BAROCLINIC ZONE OVER THE REGION IS IN THE PROCESS OF SLOWLY LIFTING NORTH AS A STRONGER NW CONUS UPPER TROUGH ADVECTS EAST ACROSS THE NW CONUS. WITH A LULL IN ANY ACTIVITY UNTIL THE MAIN UPPER TROUGH ADVECTS INTO THE AREA LATER THIS EVENING AND OVERNIGHT. THIS WILL SUPPORT WARMER TEMPS FOR ALL PLACES WED. UPPER TROUGH AND RENEWED FGEN RESPONSE WILL SUPPORT AN AREA OF SNOW ACROSS MT INTO ND LATE THIS EVENING INTO WED MORNING. THE ONLY CHANCE FOR PRECIP LOOKS TO BE POSSIBLY WED NIGHT WITH THE SECONDARY UPPER TROUGH ADVECTING INTO THE REGION. WARMER CONDS EXPECTED ALL PLACES.
638 AM EDT WED MAR 18 2015 HIGH PRESSURE WILL PROVIDE DRY AND COOL CONDITIONS ACROSS THE REGION TODAY.
524 AM EDT WED MAR 18 2015 HIGH PRESSURE OVER THE PLAINS WILL BUILD EAST INTO PENNSYLVANIA OVER THE NEXT TWO DAYS.
RAIN CHANCES INCREASE AREAWIDE WEDNESDAY AS THE UPPER LOW MOVES INTO THE REGION WITH A FEW ISOLATED THUNDERSTORMS ALSO POSSIBLE.
355 AM CDT WED MAR 18 2015 A WEAK COLD FRONT HAS PUSHED INTO CENTRAL ALABAMA AND WAS LOCATED NEAR THE I-85 CORRIDOR. BUT THE FRONT WILL BRING IN SOME SLIGHTLY COOLER AIR AND KEEP HIGHS MOSTLY IN THE 70S TODAY. A SHORT WAVE TROF WILL EJECT EASTWARD AND RAIN WILL QUICKLY OVERSPREAD CENTRAL ALABAMA OVERNIGHT. INSTABILITY WILL BE LIMITED DUE TO THE INTRUSION OF COOLER LOW LEVEL AIR.
617 AM EDT WED MAR 18 2015 LARGE AREA OF HIGH PRESSURE WILL MOVE SLOWLY ACROSS THE LOWER GREAT LAKES.
Later tonight expect an increase in low level moisture as isentropic lift increases overnight ahead of the upper level trough moving across the Southern Plains. Models are in agreement with a east northeast movement to the upper trough through the day on Wednesday with precipitation in the deformation zone across east central Kansas developing by the afternoon. Lows tonight should range from the lower 30s near the Nebraska border to the upper 30s in east central Kansas. Highs Wednesday will range from the mid 40s in the southeast to the lower 50s in north central Kansas as a cool easterly wind dominates.
A RELATIVELY BROAD UPPER TROUGH WAS ENTERING WESTERN MONTANA THIS HOUR. A 90KT JET WAS ON THE FRONT SIDE OF THIS TROUGH AND WAS PRODUCING RAIN AND SNOW SHOWERS OVER CENTRAL AND EASTERN MONTANA. THE UPPER TROUGH AXIS WILL SLIDE ACROSS THE AREA THIS AFTERNOON WITH CYCLONIC FLOW AND SOME INSTABILITY. A COLD FRONT WILL SWING ACROSS EASTERN MONTANA AND PROVIDE WESTERN AND CENTRAL ZONES A GLANCING BLOW.
CHATTANOOGA AIRPORT, TN 45 64 48 54 / 0 10 80 80 KNOXVILLE MCGHEE TYSON AIRPORT, TN 41 60 41 51 / 0 10 70 90 OAK RIDGE, TN 40 60 42 51 / 0 10 70 90 TRI CITIES AIRPORT, TN 34 57 38 51 / 0 10 50 90.
1256 AM EDT WED MAR 18 2015 HIGH PRESSURE WILL ALLOW FOR DRY CONDITIONS ACROSS THE REGION THROUGH WEDNESDAY.
Low pressure centered over WY with trough extending north through MT will shift east while an upper level weather system now approaching the Northern Rockies also moves east across the region tonight. As axis of surface and upper level troughs move east of the region Wednesday morning cigs should improve but moisture lingers and showers will redevelop Wednesday afternoon with surface winds from the W/NW.
WITHIN A PREVAILING WEAK PRESSURE PATTERN SOUTHEAST OF A WEAK HIGH PRESSURE CELL. AND WELL SOUTH OF A TROUGH. A DEEP RIDGE PERSISTS. WITH CURRENT AIR TEMPERATURES MOSTLY IN THE LOWER 70S IN KEYS ISLAND COMMUNITIES. LARGE-SCALE RIDGING ALOFT AND A FAIRLY WEAK PRESSURE PATTERN AT THE SURFACE IS LIKELY TO PERSIST ACROSS THE FLORIDA KEYS FOR MUCH OF THE NEXT SEVEN DAYS.
254 AM CDT WED MAR 18 2015 UPPER LOW CURRENTLY LIFTING NORTHEAST INTO WESTERN TEXAS EARLY THIS MORNING WITH AREAS OF LIGHT RAIN DEVELOPING ACROSS NORTHEAST OKLAHOMA IN DEFORMATION ZONE.
400 AM CDT Wed Mar 18 2015 WV imagery shows the upper trough over the lwr Trans Pecos, and slowly moving NE toward the South Plains. Further south, the Rio Grande at Presidio Int'l Bridge rose 4' last hour. Sfc flow is anticipated to veer to the S later today as high pressure moves east, and a leeside trough begins developing ahead of the next west coast trough. However, w/saturated soils and cloud cover slow to dissipate, staying toward the cooler side of guidance seems prudent for the next couple of days.
A WEAK TROUGH WILL BRING A FEW SHOWERS TONIGHT. DRY WEATHER WILL PREVAIL WEDNESDAY WITH AN UPPER RIDGE OVER THE AREA.
WITH MUCH COOLER AIR COMPARED TO RECENT DAYS TAKING UP RESIDENCE.
631 PM CDT TUE MAR 17 2015 HIGH PRESSURE CURRENTLY CENTERED OVER SE SOUTH DAKOTA WILL CONTINUE ITS TREK SE INTO AND ACROSS THE STATE THIS EVENING AND OVERNIGHT. THE UPPER MIDWEST WILL REMAIN IN THE SAME GENERAL WEATHER PATTERN WITH AN UPPER RIDGE OUT WEST AND A GENERAL TROUGH OVER THE GREAT LAKES/EASTERN U.
TEMPERATURES HAVE WARMED INTO THE LOWER 80S ACROSS THE SOUTH AND UPPER 70S ACROSS THE NORTH.
644 PM CDT TUE MAR 17 2015 UPPER LOW IS STILL SPINNING OVER THE BIG BEND REGION OF TEXAS CURRENTLY. THE LOWS FOR TONIGHT WERE TWEAKED UPWARD AS WELL. ESPECIALLY ACROSS THE NW TAF SITES WHERE THE LOWEST CIGS ARE ANTICIPATED. A WEAKENING UPPER LOW IN SOUTHWEST FLOW ALOFT WILL TRAVERSE THE REGION TONIGHT.
307 AM EDT WED MAR 18 2015 A LARGE AREA OF HIGH PRESSURE OVER THE PLAINS WILL BUILD EAST INTO PENNSYLVANIA OVER THE NEXT TWO DAYS.
INTERACTION OF THESE TWO WILL LOOK TO DRAW WEAKENING REMNANT TX UPPER LOW CLOSE ENOUGH FOR CHANCE OF LIGHT RAIN LATE TONIGHT SOUTH.
1128 PM CDT TUE MAR 17 2015 HIGH PRESSURE CURRENTLY CENTERED OVER SE SOUTH DAKOTA WILL CONTINUE ITS TREK SE INTO AND ACROSS THE STATE THIS EVENING AND OVERNIGHT. THE UPPER MIDWEST WILL REMAIN IN THE SAME GENERAL WEATHER PATTERN WITH AN UPPER RIDGE OUT WEST AND A GENERAL TROUGH OVER THE GREAT LAKES/EASTERN U.
743 PM EDT TUE MAR 17 2015 HIGH PRESSURE WILL ALLOW FOR DRY CONDITIONS ACROSS THE REGION THROUGH WEDNESDAY.
333 AM EDT WED MAR 18 2015 HIGH PRESSURE OVER THE UPPER MIDWEST WILL MOVE SOUTHEAST TO THE LOWER GREAT LAKES TONIGHT. HIGH PRESSURE OVER THE UPR MIDWEST WILL MOVE E-SE TO THE LWR GRTLKS BY THU MORNING PROVIDING DRY CONDITIONS AND LIGHT WINDS ACROSS OUR AREA. SOME HIGH CLOUDS WERE SPILLING OVER THE UPR RIDGE ACROSS THE HIGH PLAINS AND INTO THE MIDWEST EARLY THIS MORNING. WITH CLOUDS MAKING SLOW EASTWARD PROGRESS AS PAC NW SHRTWV/HIGH PLAINS RIDGE MOVES SLOWLY EAST. EXPECT A COMBINATION OF HIGH CLOUDS AND EASTERLY WINDS/MIXING BEHIND DEPARTING RIDGE WILL LIMIT DIURNAL COOLING TONIGHT TO LESS THAN INDICATED BY LATEST MOS FCSTS.
A COLD FRONT CLEARS THE AREA THIS EVENING, WITH VFR CONDITIONS EXPECTED TO PREVAIL IN ITS WAKE THROUGH THE FORECAST PERIOD.
415 AM EDT WED MAR 18 2015 HIGH PRESSURE CROSSES TODAY.
WITH NO FRONT OR COOLER AIR EXPECTED. THE NEXT UPPER LEVEL DISTURBANCE AND SAGGING SOUTHWARD COLD FRONT WILL GENERATE ANOTHER ROUND OF SHRA. THE END OF THE PRECIP IS EXPECTED BY SUN AFTERNOON/EVENING AS THE LOW AND UPPER LEVEL TROF KICKS NE OF THE REGION.
THIS WILL KEEP MOST PLACES IN THE LOWER 30S OR WARMER. BUT WITH THE HIGH ARRIVING NEAR KHTS BY MORNING. AN UPPER LOW CURRENTLY OVER NORTHERN MEXICO WILL CONTINUE TO OPEN UP AND GET ABSORBED INTO THE WESTERLIES TONIGHT AND WEDNESDAY. WOULD NOT RULE OUT SOME SNOW OCCURRING DUE TO SURFACE WET BULB TEMPS EXPECTED TO BE NEAR FREEZING AND A LACK OF SIGNIFICANT WARM AIR ALOFT.
356 AM EDT WED MAR 18 2015 A COLD FRONT HAS PUSHED EAST OF THE AREA. THERE IS THE CHANCE FOR A FEW SCATTERED SNOW SHOWERS WEDNESDAY AS AN UPPER LEVEL TROUGH REMAINS OVER THE REGION.
AT THE SURFACE A CANADIAN HIGH PRESSURE WAS ADVECTING INTO THE AREA FROM THE NORTH AND WEST TODAY. NORTHWEST MID-LEVEL FLOW WILL RESULT IN COOLER TEMPERATURES THROUGH THE UPCOMING WEEKEND AS 1000-500MB THICKNESS VALUES REMAIN NEAR OR BELOW 540 DAM AND CYCLONIC FLOW ALOFT PERSISTS.
AND THUS HAVE REMOVED THE LOW POPS FROM THE FORECAST. STAYED CLOSER TO THE WARMER RAW AND BIAS CORRECTED GUIDANCE FOR LOWS TONIGHT. WARMER AIR RETURNS TO THE AREA FOR LATTER PART OF THE WORK WEEK.
00z upper air analysis shows cut-off low that had previously been stationary over the southern Baja Peninsula has opened up and lifted into west Texas.
CLEAR SKIES CONTINUE THIS MORNING WITH A SPRAWLING AREA OF LOW PRESSURE ROTATING OVER THE SOUTHERN PLAINS.
MAINLY MID AND UPPER LEVEL CLOUDINESS WILL BE ON THE INCREASE OVER THE REGION TODAY AS A LARGE CUTOFF UPPER LEVEL LOW AT THE SW TEXAS/N MEXICO BORDER BEGINS TO OPEN UP AND EJECT EASTWARD.
1051 PM EDT TUE MAR 17 2015 A COLD FRONT HAS PUSHED EAST OF THE AREA. THERE IS THE CHANCE FOR A FEW SCATTERED SNOW SHOWERS WEDNESDAY AS AN UPPER LEVEL TROUGH REMAINS OVER THE REGION.
AN UPPER TROUGH WILL PROVIDE SCATTERED SHOWERS MAINLY OVER THE MOUNTAINS AND DESERT TODAY WITH POSSIBLE THUNDERSTORMS DURING THE AFTERNOON AND EVENING.
AND WERE MAINLY CONFINED TO NEAR THE BASE OF THE UPPER SHORT WAVE TROUGH OVER NORTHEAST OREGON. A COUPLE OF LIGHTNING STRIKES WERE DETECTED NEAR THE CENTER OF THE TROUGH EARLIER THIS EVENING. SHOWERS WILL LINGER ACROSS THE NORTH AS THE UPPER TROUGH MOVES TO THE NORTHEAST. BUT THE UPPER LEVEL SHORT WAVE TROUGH HAS YET TO PASS THROUGH OUR NRN ZONES AND THE AIR MASS WILL DESTABILIZE LATER THIS AFTERNOON. AFTER THAT THE AIR MASS WILL STABILIZE AS THE UPPER TROUGH EXITS NEWD.
AS LIFT INCREASES AHEAD OF AN UPPER LOW OVER TX. /ISSUED 653 PM CDT TUE MAR 17 2015/ A COLD FRONT WILL MOVE ACROSS THE REGION OVERNIGHT ALLOWING FOR CEILINGS TO BECOME MVFR/IFR TONIGHT INTO WEDNESDAY.
A low pressure area is forming over Southern California tonight. The weak wave will move through Wednesday morning with ridging building in behind that wave and northerly winds developing over the interior. Northerly winds will help to warm temperatures up once again into the mid 70s and even some low 80s for some of the warmer valley locations over the north.
That's where the higher rainfall amounts will accumulate.
653 PM CDT TUE MAR 17 2015 A COLD FRONT WILL MOVE ACROSS THE REGION OVERNIGHT ALLOWING FOR CEILINGS TO BECOME MVFR/IFR TONIGHT INTO WEDNESDAY.
705 PM EDT TUE MAR 17 2015 HIGH PRESSURE BUILDS IN OVERNIGHT WITH COLDER AIR.
WATER VAPOR SATELLITE TRENDS PLACE AN UPPER LEVEL LOW OVER WEST TEXAS THIS MORNING. A COLD FRONT IS LOCATED ALONG THE I-20 CORRIDOR IN CENTRAL MISSISSIPPI THIS MORNING. TEMPERATURES RANGE FROM THE LOWER 40S NEAR THE MISSOURI/KENTUCKY STATE LINE. SHOWERS AND A FEW THUNDERSTORMS HAVE DEVELOPED OVER TEXAS IN RESPONSE TO BETTER FORCING ASSOCIATED WITH THE CUTOFF UPPER LEVEL LOW AND A NEARBY SURFACE BOUNDARY.
/ISSUED 356 PM CDT TUE MAR 17 2015/ THE COLD FRONT HAS ALMOST MADE IT THROUGH THE ENTIRE FA THIS AFTERNOON. THE IMPRESSIVE MID TO UPPER LOW IS NOW STARTING TO MOVE ITS WAY TOWARD THE RIO GRANDE AND APPEARS IT WILL TAKE A MORE WESTERLY TRACK THAN ORIGINALLY ANTICIPATED (OVER THE PERMIAN BASIN).
400 AM CDT WED MAR 18 2015 WEAK HIGH PRESSURE WAS CENTERED OVER SOUTHERN MINNESOTA EARLY THIS MORNING. BUT THUS FAR DRY AIR IN THE LOW LEVELS HAS BEEN WINNING OUT YIELDING DRY CONDITIONS AT THE SURFACE.
620 PM CDT TUE MAR 17 2015 VERY QUIET WEATHER CONDITIONS THROUGH THE SHORT TERM WITH HIGH PRESSURE IN PLACE OVER THE UPPER MIDWEST. THE STRONG NWLY FLOW ALOFT WILL PERSIST THROUGH TONIGHT AND TOMORROW AS THE HIGH PRESSURE AT THE SURFACE MOVES FROM SOUTH DAKOTA/SOUTHWEST MN INTO THE MID MS VALLEY REGION. THE SFC PRES GRADIENT WILL RELAX TONIGHT AS THE RIDGE AXIS MOVES ACROSS THE AREA AND ALLOW WINDS TO SUBSIDE AND BACK TO THE W/SW. THE HIGH WILL SHIFT INTO ERN LAKE SUPERIOR WED AFTERNOON AS THE NEXT SYSTEM MOVES INTO THE PLAINS. LOW TEMPERATURES TONIGHT WILL BE SIMILAR TO LAST NIGHT BUT A FEW DEGREES WARMER. HIGH TEMPS ON WEDNESDAY WILL BE A FEW DEG WARMER AS WELL WITH AFTERNOON READINGS INTO THE UPPER 30S AND LOWER TO MID 40S.
ESPECIALLY ACROSS THE NW TAF SITES WHERE THE LOWEST CIGS ARE ANTICIPATED. A WEAKENING UPPER LOW IN SOUTHWEST FLOW ALOFT WILL TRAVERSE THE REGION TONIGHT.
708 PM EDT TUE MAR 17 2015 A COLD FRONT HAS PUSHED EAST OF THE AREA. THERE IS THE CHANCE FOR A FEW SCATTERED SNOW SHOWERS WEDNESDAY AS AN UPPER LEVEL TROUGH REMAINS OVER THE REGION.
19Z surface map showed 1036 mb Canadian high pressure over central and eastern SD while strong cold front pushing just south of TN. Forecast models drift high pressure se across central/ne IL and Ohio river valley by dawn. NNE winds should diminish light during this evening as high pressure settles in. MET and MAV has lows tonight in the lower 20s at CMI and GBG could verify if high clouds slower to move in tonight especially at CMI. Canadian high pressure will drift off to our east on Wednesday with our attention then turning to a weakening upper level system that will be drifting northeast out of the Southern Plains and into the Ohio Valley.
710 PM EDT TUE MAR 17 2015 HIGH PRESSURE WILL CONTINUE BUILDING ACROSS NORTHERN OHIO AND NORTHWEST PENNSYLVANIA TONIGHT.
COOLER AND BREEZY NEAR THE COAST WEDNESDAY. COLD FRONT PROGGED TO MOVE INTO NE FL WED AM AND PUSH SOUTH OF THE AREA DURING THE DAY. TEMPS A GOOD 20 TO 25 DEGREES COOLER THAN TODAY ALONG THE COAST. COLD FRONT PUSHES SOUTH ACROSS THE WATERS LATER TONIGHT WITH STRONG NE SURGE BEHIND IT LATER TONIGHT INTO WED. RIP CURRENTS: MODERATE RISK EXPECTED ON WEDNESDAY AS ONSHORE FLOW AND SEAS/SWELLS INCREASE BEHIND COLD FRONT.
729 PM EDT TUE MAR 17 2015 A COLD FRONT HAS PUSHED EAST OF THE AREA. THERE IS THE CHANCE FOR A FEW SCATTERED SNOW SHOWERS WEDNESDAY AS AN UPPER LEVEL TROUGH REMAINS OVER THE REGION.
In most areas leaned toward cooler guidance due to mostly clear skies.
257 AM CDT WED MAR 18 2015 EARLY THIS MORNING A CLOSED UPPER LOW WAS LOCATED OVER THE PERMIAN BASIN AND WAS PROGRESSING STEADILY NORTHEASTWARD. LIGHT RAIN WILL DIMINISH DURING THE MORNING AS THE WEAKENING UPPER LOW AND AREA OF ASCENT SHIFTS EAST.
218 AM EDT WED MAR 18 2015 A LARGE AREA OF HIGH PRESSURE OVER THE PLAINS WILL BUILD EAST INTO PENNSYLVANIA OVER THE NEXT TWO DAYS.
240 AM PDT WED MAR 18 2015 A LOW PRESSURE SYSTEM WILL BRING THE CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS TODAY FROM SANTA BARBARA COUNTY SOUTHWARD.
SO STAYED NEAR TO SLIGHTLY BELOW THE COOLER GUIDANCE.
Light freezing drizzle continues at KABI and is forecast to develop at KSJT around 00z as temperatures drop to or below freezing. Light drizzle will continue at the other sites then transition to light freezing drizzle late this evening as temperatures drop below freezing. Areas of light freezing rain/sleet may develop after midnight, mainly at KABI and KSJT.
COLD FRONT IS CURRENTLY DRAPED FROM NORTH LAREDO EASTWARD TO JUST NORTH OF ORANGE GROVE TO MATHIS TO REFUGIO TO MATAGORDA BAY. WITH TEMPS ACROSS NE ZONES ALREADY DOWN INTO THE LOW 50S.
NEARLY STATIONARY FRONT ACROSS NRN CENTRAL GA TO SERN AL TO SRN LA THIS EVENING WILL GET A NUDGE E AND SE AS MEAN LAYER TROUGH OVER THE ERN U. COLD FRONT WILL MOVE THROUGH SE GA IN THE MORNING AND NE FL DURING THE AFTN. COOLER HIGH TEMPS EXPECTED. MOISTURE WILL CONTINUE TO INCREASE TONIGHT AS A COLD FRONT CONTINUES TO EDGE CLOSER TO THE AREA. THE COLD FRONT WILL PUSH SE INTO THE AREA MONDAY AFTERNOON. WIND AND SEA CONDITIONS DETERIORATE ON MONDAY AS THE COLD FRONT MOVES INTO THE FORECAST REGION.
1020 PM EST SUN FEB 22 2015 A COLD FRONT WILL PUSH SOUTHWARD AND THROUGH THE FORECAST AREA OVERNIGHT. HIGH PRESSURE CENTERED TO THE NORTHWEST WILL DIRECT COLD AIR INTO THE AREA. SURFACE ANALYSIS SHOWS A WAVY COLD FRONT EXTENDING FROM NEAR CHARLOTTE TO SOUTH OF ATLANTA.
THE WEAKNESS OF THE FLOW MAY ALLOW WINDS TO BACK A BIT OVER THE COOLER GULF WATERS. THE LAST REMAINING TAIL END OF AN ATLANTIC RIDGE IS WEAKENING ACROSS FLORIDA. WINDS WILL TEND TO BE MORE BACKED OVER OUR COOLER GULF SIDE WATERS.
Cold air will continue to move into the area tonight as strong high pressure becomes centered to our north over the Midwest/Cornbelt by 12z/daybreak Monday.
ALLOWING WAA TO COMMENCE THE WARMER INCOMING AIR WILL ALLOW HIGHS TMRW TO RISE TO THE MID-TEENS TO MID-20S. LONG RANGE MODELS REMAINED IN GOOD AGREEMENT ON THE EVOLUTION OF THE LONG WAVE TROUGH HOLDING ACROSS THE EASTERN 2/3 OF NORTH AMERICA THRU MIDWEEK.
AN UPPER RIDGE ANCHORED OFF THE WEST COAST WILL MOVE ONSHORE INTO B. AND THE PACIFIC NORTHWEST THROUGH MONDAY AS AN UPPER LOW IN CALIFORNIA AND NEVADA CONTINUES TO MOVE SOUTHWARD.
THESE WINDS WILL BE STRONGEST OVER THE HIGHER TERRAIN AND ALONG THE COAST. OFFSHORE HIGH PRESSURE AND A THERMAL TROUGH NEAR THE COAST ARE PRODUCING GUSTY NORTH TO NORTHEAST WINDS AND STEEP CHOPPY SEAS.
CLOSE TO THE COLD FRONT. THE COLD FRONT WILL CONTINUE SOUTHWARD THIS AFTERNOON AND EVENING. MODELS THIS MORNING TRENDED SLIGHTLY WARMER TONIGHT. THERE IS HIRES GUIDANCE SUPPORTIVE OF THE FREEZING LINE DROPPING INTO NORTHWEST CENTRAL ALABAMA AROUND MIDNIGHT. WITH LOCATIONS ALONG AND NORTH OF I-20 FALLING TO OR BELOW FREEZING BY SUNRISE. BUT PROFILES ARE SUPPORTIVE OF FREEZING RAIN WITHIN THE FREEZING RAIN ADVISORY AREA.
BUT COOLER AND POSSIBLY UNSETTLED WEATHER WILL MOVE BACK INTO THE GREAT BASIN BY THE END OF THE WEEK.
402 PM MST SUN FEB 22 2015 THE LOW PRESSURE CENTER EXPECTED TO DEVELOP OVER WESTERN NEVADA THIS MORNING ENDED UP DEVELOPING FURTHER WEST IN CALIFORNIA. WITH THE LOW PRESSURE SYSTEM FURTHER WEST. SNOW WATER RATIOS WILL INCREASE SLIGHTLY TONIGHT TOO WITH COOLER AIR IN PLACE DURING THE NIGHT. PRECIPITATION IS EXPECTED TO CONTINUE THROUGHOUT THE DAY TOO BUT ACCUMULATIONS WILL BE LESS WITH DAYTIME TEMPERATURES NEAR FREEZING IN MANY PLACES. TEMPERATURES COULD BE A COUPLE DEGREES WARMER IN THE SOUTHERN VALLEYS WHICH WOULD ALLOW A RAIN/SNOW MIX AT LOWER VALLEY ELEVATIONS.
WHILE THE RIDGES LIKEWISE WILL DO BETTER AS UPSLOPE COMBINED WITH LOW LEVEL INSTABILITY BEHIND THE FRONT AS MOISTURE ERODES WILL LIKELY ALLOW FOR A SMALL BONUS IN SNOW SHOWER ACTIVITY. THE LATEST 18Z MODEL SOLUTIONS TRY TO HOLD ONTO SOME LOW LEVEL MOISTURE WEST OF THE RIDGES THROUGH THE NIGHT. THIS WILL BE LOOKED AT FURTHER AS MORE DATA ROLLS IN THIS EVENING AND THE ARCTIC COLD FRONT PASSES BY. BUT BUILDING HIGH PRESSURE IS EXPECTED TO SLACKEN THE WIND AND PRECLUDE A CONTINUATION OF THE WIND CHILL ADVISORY AS MONDAY EVENING FALLS. AN UPPER TROUGH OVER THE NORTHEASTERN CONUS. AND ITS ASSOCIATED SURFACE COLD FRONT.
ARCTIC HIGH PRESSURE WILL NOSE SOUTH ACROSS THE CENTRAL PLAINS TONIGHT AND ALTHOUGH SOME LINGERING MID AND HIGH LEVEL CLOUDS WILL PERSIST.
THOSE COOLER TEMPS AND DRIER AIR ARE JUST OFF TO OUR NORTHWEST. BIGGEST THING THIS EVENING REVOLVES AROUND THIS WEAK SYSTEM MOVING THROUGH THE LOWER MS AND TENNESSEE RIVER VALLEYS.
AT 8 PM EST, the regional surface analysis showed a slow-moving cold front roughly from Athens, GA to Macon and southwestward to near New Orleans. The cold front will reach the Tallahassee area by around daybreak, as it transitions into an anafront (with most of the rain behind the cold front).
TEMPERATURES WILL BE COLD TONIGHT AND IN THE LOWER SINGLE POSITIVE DIGITS. FOR TOMORROW AND OTHER THAN THE AFOREMENTIONED SNOW, HIGH PRESSURE WILL MOVE ACROSS THE PLAINS WITH WEAK SOUTHERLY FLOW BY EVENING. HIGHS WILL STILL BE WELL BELOW NORMAL AND HAVE GONE WITH THE COOLER SIDE OF GUIDANCE WITH UPPER TEENS TO LOW TWENTIES ACROSS THE FORECAST AREA OF RESPONSIBILITY. NORTHERN BRANCH UPPER LEVEL TROUGH STILL FORECAST BY ALL THE MODELS TO CROSS WESTERN KANSAS MONDAY NIGHT WITH CLEARING SKIES DEVELOPING FROM NORTH TO SOUTH.
HIGH PRESSURE OVER EASTERN NORTH DAKOTA WILL CONTINUE TO ROTATE SOUTHEAST INTO MINNESOTA AND IOWA TONIGHT. CURRENT SURFACE ANALYSIS PLACES COLD HIGH PRESSURE SLIDING OVER THE DAKOTAS INTO EASTERN MINNESOTA. WHILE RIDGE REMAINS OFF THE WEST COAST. STILL SOME QUESTION ON HOW LONG IT WILL TAKE THE WARMER AIR TO REACH THE EASTERN CWA WHERE WIND CHILL ADVISORY CONTINUES. A MUCH MILDER DAY IS EXPECTED WITH WARMER AIRMASS SETTLING IN. HIGH AMPLITUDE RIDGE ACROSS THE EAST PACIFIC/BAY OF ALASKA AND LONGWAVE TROUGH ACROSS THE EASTERN CONUS. THIS PATTERN IS CONDUCIVE TO FREQUENT ARCTIC OUTBREAKS FOLLOWED BY BRIEF PERIODS OF RETURN FLOW AND WARMER TEMPERATURES. MONDAY WILL BE THE FIRST PERIOD OF RETURN FLOW AND WARMER TEMPERATURES.
THERE SHOULD BE ENOUGH OF A PRESSURE GRADIENT IN PLACE THAT WINDS STAY IN THE 5-10 MPH RANGE AND CAUSE THE LOWER WIND CHILLS. WINDS WILL SHIFT AROUND TO THE SOUTHWEST TOMORROW MORNING AND HELP TO BRING SOME WARMER AIR INTO THE REGION AND END THE NEED FOR AN ADVISORY.
659 PM EST SUN FEB 22 2015 AVIATION A NORTHERLY FLOW OF ARCTIC AIR WILL CONTINUE THROUGH TONIGHT AS HIGH PRESSURE DIVES SOUTHEASTWARD THROUGH THE PLAINS.
ALL MODELS SHOW ACCUMULATING SNOW ALONG AND SOUTH OF I-40 WITH SLEET AND FREEZING RAIN FURTHER SOUTH. AND FREEZING RAIN IS THE MAIN CHALLENGE TONIGHT. WITH A FEW AREAS IN THE LOWER 40S WHERE SUN PEEKED THROUGH THIS AFTERNOON. THE CURRENT THINKING IS THAT FREEZING RAIN WILL EXIST FOR A FEW HOURS BEFORE MIDNIGHT. ANOTHER DISTURBANCE WILL TRACK ACROSS NORTH MISSISSIPPI AND MORE CHANCES FOR SLEET AND FREEZING RAIN WILL EXIST OVER EXTREME SOUTHEAST ARKANSAS AND PORTIONS OF NORTHWEST MISSISSIPPI.
LL FREEZING TEMPS AT 2. /ISSUED 259 PM CST SUN FEB 22 2015/ RAIN CONTINUES ACROSS THE REGION THIS AFTERNOON WITH TEMPERATURES HOLDING STEADY IN THE LOW TO MID 40S AREAWIDE. AS COLD HIGH PRESSURE CONTINUES TO SURGE SOUTH. RAIN TO TRANSITION INTO SLEET AND FREEZING RAIN ACROSS THE INTERSTATE 20 CORRIDOR AFTER MIDNIGHT. SHOULD SEE RAIN TRANSITIONING TO FREEZING RAIN ACROSS DEEP EAST TEXAS AND WEST CENTRAL LOUISIANA. TEMPERATURES TO REMAIN AT OR BELOW FREEZING THROUGHOUT THE DAY MONDAY. FREEZING RAIN. THIS UNCERTAINTY EXISTS DUE TO THE FACT THAT TEMPERATURES WILL REMAIN AT OR SLIGHTLY BELOW FREEZING ACROSS MANY AREAS THROUGHOUT THE DURATION OF THE EVENT.
350 PM MST SUN FEB 22 2015 A COLD FRONT HAS STALLED JUST SOUTH OF THE UTAH BORDER TODAY.
HIGH PRESSURE OVERHEAD WILL ALLOW TEMPERATURES TO BOTTOM OUT EARLY. AS THE HIGH CONTINUES SOUTH WE GET INTO SOUTHWEST FLOW/WARM ADVECTION.
A COLD FRONT IS EXPECTED TO MOVE INTO NORTH FLORIDA ON MONDAY WHICH WILL WEAKEN FURTHER THE WEAK HIGH PRESSURE CURRENTLY ACROSS THE REGION. AT THE MID TO UPPER LEVELS WEAK RIDGING WILL BUILD ACROSS THE AREA AND THE SUBSIDENCE AT THE MID TO UPPER LEVELS WILL HELP TO SUPPRESS SHOWER ACTIVITY.
High pressure aloft will continue to provide dry and stable conditions.
HIGH PRESSURE WILL GRADUALLY EXIT THE REGION OVERNIGHT ALLOWING A WEAK COLD FRONT TO SETTLE SOUTHWARD ACROSS THE EASTERN GULF OF MEXICO ON MONDAY.
WITH FREEZING OR SUB- FREEZING TEMPERATURES REACHING THE EAST TEXAS LAKES AND CENTRAL LOUISIANA MONDAY MORNING. WITH FREEZING TEMPERATURES REACHING NEAR THE COAST BY LATE MONDAY NIGHT. WITH SFC TEMPERATURES BELOW FREEZING. HAVE GONE AHEAD AND ISSUED A FREEZING RAIN ADVISORY FOR THE AREAS MOST LIKELY TO BE IMPACTED. WITH ELEVATED ROADWAYS AND BRIDGES AT THE GREATEST RISK.
632 PM EST SUN FEB 22 2015 ANOTHER ARCTIC COLD FRONT WILL CROSS THE REGION TONIGHT.
SO THERE IS A CONCERN FOR SOME FOG OR FREEZING FOG. AS WELL AS LIGHT DRIZZLE OR LIGHT FREEZING DRIZZLE. SOME FREEZING RAIN IS POSSIBLE SOUTHERN PLATEAU AND VALLEY LATE BUT AMOUNTS SHOULD BE VERY LIGHT AS PRECIPITATION AMOUNTS SHOULD BE LESS THAN 0. CHATTANOOGA AIRPORT, TN 34 38 26 45 / 70 30 10 20 KNOXVILLE MCGHEE TYSON AIRPORT, TN 32 35 24 41 / 30 10 10 20 OAK RIDGE, TN 30 34 22 42 / 20 10 10 20 TRI CITIES AIRPORT, TN 32 32 18 40 / 20 10 10 20.