Aikyam-Lab/Synoptic-Bench huggingface dataset:
625 PM EST FRI MAR 6 2015 A TRANQUIL PERIOD OF WEATHER IS EXPECTED THROUGH SATURDAY NIGHT AS HIGH PRESSURE REMAINS ON CONTROL ACROSS THE AREA. THE EASTERN CONUS/NOAM TROUGH SHOULD BECOME MORE BROAD BY THE START OF THE PERIOD. WHILE A RIDGE WILL LINGER NEAR THE WEST COAST OF THE CONUS. A CLOSED LOW IS ANTICIPATED TO BE OVER THE SOUTHERN ROCKIES AND NORTHERN MEXICO. THE INITIAL SOUTHWEST CLOSED LOW SHOULD BEGIN TO OPEN UP BY THE END OF THE WEEKEND. DISTURBANCES EMBEDDED WITHIN THE SOUTHERN STREAM SHOULD CONTINUE TO EJECT OUT OF THE TROUGH OVER THE SOUTHERN ROCKIES INTO THE SOUTHERN PLAINS.
RESULTING IN TEMPERATURES 5-10 DEGREES WARMER THAN CLIMATOLOGY ACROSS MUCH OF MID-AMERICA. ECMWF/GFS CONSENSUS SUPPORT A DEEPENING TROUGH ACROSS THE SOUTHERN PLAINS AND LOWER MISSISSIPPI VALLEY BY LATE WEEK/WEEKEND. RELATIVELY LIGHT WINDS SHOULD KEEP THE FIRE DANGER ON THE LOW SIDE THE NEXT SEVERAL DAYS.
719 PM EST FRI MAR 6 2015 HIGH PRESSURE WILL SLIDE SOUTHEAST OF THE AREA OVERNIGHT. A COLD FRONT WILL APPROACH LATER SATURDAY THEN CROSS THE REGION SATURDAY NIGHT.
500 PM CST FRI MAR 6 2015 CONCERN IN THE SHORT TERM INCLUDES A COUPLE WAVES OF LOW PRESSURE THAT MAY IMPACT PARTS OF THE AREA WITH SOME LIGHT SNOWFALL. WILL BE WATCHING AN AREA OF LOW PRESSURE DROPPING SOUTHEAST OUT OF EASTERN SASKATCHEWAN TOWARD THE AREA. THIS LOW IS EXPECTED TO DEEPEN AND BE LOCATED JUST NORTH OF LAKE SUPERIOR. LOOKS LIKE A BREEZY DAY AS THAT AREA OF LOW PRESSURE DEPARTS TO THE EAST KEEPS US IN A FAIRLY TIGHT PRESSURE GRADIENT. FAIRLY NEUTRAL TEMPERATURE ADVECTION NOTED BEHIND THIS WAVE OF LOW PRESSURE IN THE THERMAL FIELD. SO LOOKS LIKE HIGHS SHOULD TOP OFF IN THE MIDDLE 30S TO THE LOWER 40S. THIS IS IN RESPONSE TO AN APPROACHING MID-LEVEL TROUGH OUT OF THE DAKOTAS AND INTERACTION WITH RIGHT ENTRANCE REGION 90-110KT 300MB JET/850-500MB FRONTOGENESIS.
606 PM EST FRI MAR 6 2015 HIGH PRESSURE WILL BUILD SOUTHEAST OVER THE STATE TONIGHT. A WEAK AREA OF LOW PRESSURE WILL PASS NORTH OF THE REGION TONIGHT AND SATURDAY. IDEAL RAD COOLING SCENARIO ACROSS THE LOWER SUSQ VALLEY WITH CLEAR SKY/CALM WIND MAY RESULT IN ANOTHER NIGHT OF RECORD COLD. HIGHS WILL TOP FREEZING OVER MUCH OF THE REGION.
650 PM EST FRI MAR 6 2015 HIGH PRESSURE HAS MOVED EAST ACROSS EASTERN KENTUCKY. A TRANQUIL PERIOD OF WEATHER IS EXPECTED THROUGH SATURDAY NIGHT AS HIGH PRESSURE REMAINS ON CONTROL ACROSS THE AREA. THE EASTERN CONUS/NOAM TROUGH SHOULD BECOME MORE BROAD BY THE START OF THE PERIOD. WHILE A RIDGE WILL LINGER NEAR THE WEST COAST OF THE CONUS. A CLOSED LOW IS ANTICIPATED TO BE OVER THE SOUTHERN ROCKIES AND NORTHERN MEXICO. THE INITIAL SOUTHWEST CLOSED LOW SHOULD BEGIN TO OPEN UP BY THE END OF THE WEEKEND. DISTURBANCES EMBEDDED WITHIN THE SOUTHERN STREAM SHOULD CONTINUE TO EJECT OUT OF THE TROUGH OVER THE SOUTHERN ROCKIES INTO THE SOUTHERN PLAINS.
KDFW/KDAL GROUND OPERATIONS WILL SEE 2 TO 3 HOURS OF FREEZING TEMPERATURES AROUND DAYBREAK SATURDAY THEN AN AFTERNOON HIGH OF 58F DEGREES. A BLOCKING HIGH OVER NORTHERN CALIFORNIA AND AN UPPER LOW OVER NORTHERN BAJA WILL PIVOT COUNTER-CLOCKWISE SATURDAY AFTERNOON WITH THE UPPER LOW EJECTING EASTWARD TOWARD TEXAS.
THEN AS THE LOW LEVEL JET STRENGTHENS. THE MID/UPPER LEVEL LOW OVER THE CENTRAL ROCKIES WILL MOVE EAST-NORTHEAST INTO THE UPPER MIDWEST/WESTERN GREAT LAKES REGION LATE THURSDAY NIGHT. A WEAK SHORT WAVE TROUGH OVER NORTHEAST MEXICO WILL MOVE INTO SOUTH-CENTRAL TEXAS TONIGHT WITH A DIVERGENT FLOW ALOFT AS 25H JET STREAK MOVES ACROSS NORTHERN MEXICO.
A MORE DISTINCT TROF PASSAGE THROUGH THE MORNING AND FORENOON HOURS TOMORROW /THURS/ WILL LARGELY PUSH THAT CLOUD MASS TO THE SOUTHEAST. SHOULD BE MORE SUN ACROSS THE NORTH AND THEREFORE WARMER TEMPS THERE.
A COLD FRONT MOVING INTO NE OK BY EARLY AFTERNOON AND THROUGH WESTERN AR BY EARLY EVENING WILL BE THE FOCUS FOR RENEWED AFTERNOON CONVECTION WITH CLEARING AND VFR CONDITIONS ONCE THE FRONT PASSES. THE THREAT WILL INCREASE DURING THE EVENING AND OVERNIGHT AS THE LOW LEVEL JET INCREASES. THE LOW LEVEL JET COULD ALSO RESULT IN ADDITIONAL LATE EVENING DEVELOPMENT WEST OF INTERSTATE 35 THAT COULD AFFECT NORTHEAST OKLAHOMA AND POSSIBLY INTO FAR NORTHWEST ARKANSAS NEAR TO AFTER MIDNIGHT. WITH MORE THUNDERSTORM DEVELOPMENT LIKELY ALONG THE COLD FRONT IN FAR EASTERN OKLAHOMA AND WESTERN ARKANSAS. THE WORK WEEK SHOULD END ON A COOLER AND DRIER NOTE WITH HIGH PRESSURE OVER THE REGION. BRINGING THE WARMER WEATHER AND HIGHER MOISTURE BACK INTO THE REGION.
A COLD FRONT WILL MOVE ACROSS THE AREA DURING THE EARLY TO MID MORNING HOURS ON THURSDAY. A COLD FRONT WILL WORK ITS WAY THROUGH THE AREA LATE TONIGHT AND TOMORROW WITH COOLER TEMPS EXPECTED.
1138 PM EDT WED APR 8 2015 A NEARLY STATIONARY FRONT JUST SOUTH OF PENNSYLVANIA AND STRONG HIGH PRESSURE OVER QUEBEC WILL COMBINE TO KEEP MOIST AND COOL CONDITIONS OVER THE REGION THROUGH THURSDAY.
CURRENT TRENDS AND THE HIGH RESOLUTION MODELS BRING A SLIGHT CHANCE OF A SHOWER TO KCLL AND KUTS OVERNIGHT TONIGHT BETWEEN ABOUT 06Z AND 11Z. THE FIRST LARGE SCALE TROF PASSES WELL NORTH OF THE AREA TOMORROW.
COULD SEE A FEW SHOWERS AND POSSIBLY THUNDERSTORMS DURING THE AFTERNOON THURSDAY AS A COLD FRONT APPROACHES FROM THE WEST. THE WATER VAPOR SHOWS A GOOD KICKER MOVING TOWARD THE CALIFORNIA COASTLINE NOW AND A DEEPENING TROUGH HEADED SOUTH QUICKLY IN IT/S WAKE.
HIGH PRESSURE OVER THE EASTERN PACIFIC WILL BUILD ACROSS THE REGION THROUGH LATE WEEK. MODERATE HIGH PRESSURE AREA CONTINUES TO BUILD OVER THE REGION. THERE COULD BE A FEW PATCHES OF VALLEY FOG IN THE MORNING THEN SUNNY WEATHER IS EXPECTED THURSDAY WITH WARMER TEMPERATURES. THE GFS'S CLOSED LOW OVER THE EPAC SOLUTION IS MORE IN LINE WITH SPRING WEATHER. SFO BRIDGE APPROACH. WEAK HIGH PRESSURE OFF THE CALIFORNIA COAST WILL BRING LIGHT NORTHWEST WINDS TONIGHT AND THURSDAY.
1208 AM EDT THU APR 9 2015 A STATIONARY FRONT WILL REMAIN ACROSS THE AREA TONIGHT BUT SHOULD LIFT NORTH ON THURSDAY AHEAD OF LOW PRESSURE APPROACHING THE GREAT LAKES.
5 deg C/km), moisture looks similar (mixing ratios around 12-14 g/kg), 0-6km shear will be greater, and there will be a synoptic scale boundary (cold front) to act as a focused lifting mechanism. The Flash Flood Watch does not correspond with the highest PoP values in the grids because it is based on the expected impacts if those rainfall amounts occur instead of being a proxy forecast for where rain is most likely to occur.
1054 PM EDT WED APR 8 2015 A NEARLY STATIONARY FRONT JUST SOUTH OF PENNSYLVANIA AND STRONG HIGH PRESSURE OVER QUEBEC WILL COMBINE TO KEEP MOIST AND COOL CONDITIONS OVER THE REGION THROUGH THURSDAY.
40 AN UPPER LEVEL RIDGE OVER THE GULF EXTENDED FAR ENOUGH WEST TO HELP SCATTER OUT THE MVFR DECK THAT WAS FORMING OVER THE AVIATION SITES EARLIER THIS EVENING. THE MODELS WEAKEN THE RIDGE AND DEVELOP MVFR CONDITIONS OVER ALL THE SITES BETWEEN 06Z AND 09Z.
THE RIDGE OF HIGH PRESSURE THAT EXTENDED OVER THE REGION HELPED TEMPERATURES CLIMB INTO THE LOWER 90S IN SOME OF OUR SE GEORGIA LOCATIONS. UNDER THE INFLUENCE OF A RIDGE OF HIGH PRESSURE THIS EVENING WITH NO FRONTS IN THE AREA.
958 PM EDT WED APR 8 2015 LOW PRESSURE WELL SOUTH OF LONG ISLAND THIS EVENING TRACKS EAST AS COLD HIGH PRESSURE NOSES IN FROM THE CANADIAN MARITIMES THROUGH THURSDAY.
937 PM EDT WED APR 8 2015 A NEARLY STATIONARY FRONT JUST SOUTH OF PENNSYLVANIA AND STRONG HIGH PRESSURE OVER QUEBEC WILL COMBINE TO KEEP MOIST AND COOL CONDITIONS OVER THE REGION THROUGH THURSDAY.
952 PM EDT WED APR 8 2015 A STATIONARY FRONT WILL REMAIN ACROSS THE AREA TONIGHT BUT SHOULD LIFT NORTH ON THURSDAY AHEAD OF LOW PRESSURE APPROACHING THE GREAT LAKES.
514 PM MDT WED APR 8 2015 THE H5 TROUGH/COLD FRONT PASSING THROUGH THE REGION IS KEEPING WIDESPREAD GUSTS TO 30 AND 40 MPH GOING THROUGHOUT EASTERN UT AND WESTERN CO. ALLOWING LOW TEMPS TONIGHT TO REACH INTO THE LOWER 20S AT MANY LOCATIONS AND A HARD FREEZE FOR THE LOW VALLEYS. THE COOLER TEMPERATURES OVER THE NEXT 24 HOURS WILL BE SHORT- LIVED AS HIGH PRESSURE BEGINS TO BUILD BACK INTO THE REGION BY THURSDAY NIGHT. TEMPS WILL BE ON THE UPSWING AFTER THE COOLER WEATHER OF TODAY AND THU.
MAIN UPPER LOW HAS MOVED EAST BUT LIGHT RAIN AND SNOW SHOWERS CONTINUE IN IDAHO MOUNTAIN ZONES. THESE SHOWERS SEEM TO BE ASSOCIATED WITH A SECOND WEAKER SHORT WAVE TROUGH OVER WASHINGTON. THAT TROUGH WILL TAKE ITS TIME MOVING ACROSS NRN IDAHO THURSDAY AND WRN MONTANA THURSDAY EVENING. SHOWERS WILL INCREASE AGAIN THURSDAY BUT THIS TIME IN THE IDAHO MOUNTAIN ZONES AS THE UPPER TROUGH MOVES BY. CLOSEST TO THE UPPER TROUGH. THE TROUGH WILL KEEP TEMPS COOL BEFORE FINALLY EXITING EAST THURSDAY NIGHT.
553 PM MDT WED APR 8 2015 AN UPPER TROUGH WILL MOVE EAST OF THE ROCKIES AND INTO THE PLAINS TONIGHT AND THURSDAY MORNING. THE TROUGH WILL SHIFT EAST INTO THE MISSOURI VALLEY THURSDAY AFTERNOON. A COLD FRONT WILL MOVE IN BEHIND THE TROUGH THURSDAY. DYNAMICS FROM THE UPPER TROUGH TONIGHT WILL BRING A CHANCE OF SHOWERS TO MAINLY YUMA COUNTY AND THE EXTREME SOUTHWEST NEBRASKA ZONES WHERE H8-7 LAYER MEAN RH IS THE BEST. THE COLD FRONT THAT MOVES INTO THE FA EARLY THURSDAY MORNING SHOULD ERODE THE STRATUS AND FOG FROM WEST TO EAST. MAX TEMPERATURES THURSDAY BEHIND THE COLD FRONT SHOULD ONLY REACH INTO THE LOWER 50S TO MID 50S.
938 PM CDT WED APR 8 2015 AHEAD OF AN APPROACHING MIDLEVEL HEIGHT TROF. THE COLD FRONT WILL THEN PROGRESS SOUTHEASTWARD TOWARD OUR FORECAST AREA THURSDAY AFTERNOON THEN MOVE ACROSS THE AREA THURSDAY NIGHT. THE CHANCE OF STORMS WILL RAPIDLY DECREASE FROM THE NW FRI AS COOLER AND DRIER AIR ADVECTS INTO THE REGION.
A COLD FRONT WILL MOVE ACROSS THE AREA THURSDAY. THIS IS CERTAINLY THE AREA WITH THE HIGHEST CONFIDENCE IN STORM COVERAGE.
WEAK RIDGING IS NOTED FROM ABOUT KBRO TOWARD THE NORTH CENTRAL GULF COAST. CURRENT TRENDS AND THE HIGH RESOLUTION MODELS BRING A SLIGHT CHANCE OF A SHOWER TO KCLL AND KUTS OVERNIGHT TONIGHT BETWEEN ABOUT 06Z AND 11Z. THE FIRST LARGE SCALE TROF PASSES WELL NORTH OF THE AREA TOMORROW.
613 PM MDT WED APR 8 2015 FORECAST FOR TODAY AND EARLY TONIGHT APPEARS TO BE ON TRACK AS THE NORTHERN UPPER LEVEL LOW ACROSS CENTRAL WYOMING IS DEVELOPING THIS AFTERNOON. INCREASED SNOW ACCUMULATIONS BETWEEN 1 TO 3 INCHES ALONG AND NEAR THE PINE RIDGE FROM NEAR DOUGLAS EASTWARD TO JUST SOUTHWEST OF CHADRON NEBRASKA.
728 PM EDT WED APR 8 2015 A NEARLY STATIONARY FRONT JUST SOUTH OF PENNSYLVANIA AND STRONG HIGH PRESSURE OVER QUEBEC WILL COMBINE TO KEEP MOIST AND COOL CONDITIONS OVER THE REGION THROUGH THURSDAY.
(PREVIOUS) RIDGING PATTERN FIRMLY ENTRENCHED OVER THE REGION. H85-H50 ANALYSIS SHOWS THE RIDGE DISPLACED TO THE S. THE PATTERN WILL ONLY GROW STRONGER OVER THE NEXT 24-36HRS AS A SHORT WAVE TROF OVER THE ROCKY MTNS PUSHES INTO THE CENTRAL PLAINS AND SHUNTS THE MID LVL RIDGE NWD. POSITION OF THE RESULTING DEEP RIDGE AXIS WILL GENERATE A PERSISTENT E/SERLY H100-H70 FLOW AND AN E/NERLY H85-H50 FLOW ACRS THE REGION. HIGH PRES RIDGE AXIS EXTENDING FROM BERMUDA ACRS THE FL PANHANDLE MAINTAINS A LIGHT TO GENTLE E/SE BREEZE ACRS THE LCL ATLC.
A COLD FRONT WILL MOVE ACROSS THE TERMINAL SITES THIS MORNING WITH NW TO N WINDS IN ITS WAKE. A COLD FRONT WILL MOVE ACROSS THE AREA DURING THE EARLY TO MID MORNING HOURS ON THURSDAY. A COLD FRONT WILL WORK ITS WAY THROUGH THE AREA LATE TONIGHT AND TOMORROW WITH COOLER TEMPS EXPECTED.
/ISSUED 250 PM EDT WED APR 8 2015/ DRY AIR WILL CONTINUE TO MOVE INTO THE REGION TONIGHT INTO TOMORROW AS A RIDGE OF HIGH PRESSURE REMAINS IN PLACE. EAST TO SOUTHEASTERLY FLOW WILL ALSO CONTINUE, WHICH WILL ALLOW TEMPERATURES TO WARM INTO THE LOWER 80S ACROSS THE EAST COAST METRO AREAS TO THE LOWER 90S ACROSS INTERIOR SECTIONS ON THURSDAY.
924 PM CDT WED APR 8 2015 SOME DRIZZLE/LIGHT RAIN FALLING IN CENTRAL AND NORTH CENTRAL SD THIS EVENING HAS ACCUMULATED TO A FEW HUNDREDTHS OF INCH AT PIERRE AND MOBRIDGE. RADAR ECHOES IN WESTERN SD AND NORTHWEST NEBRASKA THIS EVENING SHOULD CONTINUE TO EXPAND NORTHEAST ACROSS MOST OF OUR CWA THROUGH THE NIGHT AS LIFT FROM THE SHORT WAVE TROUGH MOVES IN. WILL STAY WITH THE HIGH POPS FOR TONIGHT. AN AREA OF LOW PRESSURE CURRENTLY ALONG THE FRONT RANGE OF THE ROCKIES WILL CROSS THE CENTRAL PLAINS TONIGHT AND OVER IOWA BY THURSDAY MORNING. AN AREA OF HIGH PRESSURE WILL BUILD ACROSS THE REGION THROUGH THE REST OF THE SHORT TERM. THIS HIGH PRESSURE WILL BRING SEASONAL LOWS FOR THURSDAY NIGHT.
THE SURFACE BOUNDARY, WHICH WAS LOCATED OVER SOUTHWEST KANSAS LATE THIS AFTERNOON/EARLY EVENING, WILL MOVE SOUTH AS AN UPPER LEVEL TROUGH CROSSES THE CENTRAL HIGH PLAINS. BASED ON THE SURFACE DEW POINTS EXPECTED EARLY THURSDAY MORNING, SOME MID OR HIGH CLOUDS PRECEDING THE UPPER LEVEL TROUGH, AND A DEVELOPING NORTHWESTERLY FLOW THE PREVIOUS FORECAST STILL APPEARS ON TRACK WITH LOWS BOTTOMING OUT MAINLY IN THE 40S ACROSS WESTERN KANSAS.
STRONG GUSTY WINDS WILL DIMINISH THIS EVENING ACROSS NORTHERN ARIZONA AS THE DRY COLD FRONT HEADS EAST.
A LINGERING PORTION OF AN UPPER LOW WAS CENTERED OVER CENTRAL WASHINGTON THIS AFTERNOON AND EVENING AND PRODUCED A FEW SHOWERS AND THUNDERSTORMS OVER SOUTHWEST WASHINGTON AND NORTHWEST OREGON. THIS LOW WILL CONTINUE TO SLOWLY MOVE EAST THURSDAY.
CHATTANOOGA AIRPORT, TN 64 84 64 72 / 10 20 90 90 KNOXVILLE MCGHEE TYSON AIRPORT, TN 62 83 64 70 / 10 20 70 90 OAK RIDGE, TN 63 83 63 70 / 10 20 80 90 TRI CITIES AIRPORT, TN 56 81 60 70 / 30 30 70 90.
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN UPPER LEVEL PATTERN CONSISTING OF LONGWAVE TROUGHING PUSHING EASTWARD THROUGH THE INTER-MOUNTAIN WEST. WITH DOWNSTREAM RIDGING IN PLACE ACROSS MUCH OF THE EASTERN HALF OF THE NATION. THIS INCLEMENT WEATHER WILL BE STAYING AWAY FROM OUR REGION IN THE SHORT-TERM AS WEAK UPPER RIDGING REMAINS IN PLACE AND KEEPS OUR LOCAL FORECAST GENERALLY WARM AND BENIGN. ATLANTIC HIGH PRESSURE WILL CONTINUE TO RIDGE BACK WESTWARD OVER THE FL PENINSULA/EASTERN GULF PROVIDING A LIGHT EAST/SE SYNOPTIC FLOW. ONCE AGAIN THE RIDGING ALOFT AND GENERALLY DRY AIR ALOFT WILL ACT AGAINST MUCH IN THE WAY OF LATE DAY CONVECTION (DESPITE THE FAVORABLE SEA-BREEZE / LARGE SCALE FLOW SETUP). HIGH PRESSURE TO OUR NORTHEAST WILL KEEP EAST TO SOUTHEAST WINDS IN PLACE FOR THE NEXT FEW DAYS.
/ISSUED 938 PM CDT WED APR 8 2015/ AHEAD OF AN APPROACHING MIDLEVEL HEIGHT TROF. THE COLD FRONT WILL THEN PROGRESS SOUTHEASTWARD TOWARD OUR FORECAST AREA THURSDAY AFTERNOON THEN MOVE ACROSS THE AREA THURSDAY NIGHT. THE CHANCE OF STORMS WILL RAPIDLY DECREASE FROM THE NW FRI AS COOLER AND DRIER AIR ADVECTS INTO THE REGION.
THE COLD UPPER LEVEL LOW PRESSURE SYSTEM OVER WYOMING THIS EVENING WILL CONTINUE EAST AWAY FROM UTAH OVERNIGHT.
935 PM EST THU FEB 19 2015 WIDESPREAD LIGHT SNOWS AND SNOW SHOWERS WILL CONTINUE TONIGHT AS LOW PRESSURE OVER EASTERN MAINE MOVES INTO THE CANADIAN MARITIMES BY FRIDAY MORNING.
352 PM PST THU FEB 19 2015 HIGH PRESSURE OVER THE WEST COAST WILL MAKE FOG POSSIBLE IN THE SAN JOAQUIN VALLEY EACH NIGHT INTO THE MORNING HOURS. UPPER RIDGE OVER CA REMAINS DOMINANT TODAY WITH A GENERALLY DRY AND MILD DAY ACROSS OUR AREA. THE 12Z WRF INDICATES THE RIDGE IS WILL BREAK DOWN AND SHIFT OFFSHORE TONIGHT HOWEVER. THIS WILL ALSO RESULT IN A COOLER NORTHERLY FLOW ALOFT OVER CENTRAL CA. THE MAIN IMPACT THAT THIS WILL HAVE WILL BE COOLER DAYTIME TEMPERATURES ON FRIDAY MOST NOTICEABLY OVER THE HIGHER ELEVATIONS AS HEIGHTS AND THICKNESSES LOWER. TEMPERATURES WILL CONTINUE TO TREND DOWNWARD ON FRIDAY AS THE RIDGE RE-AMPLIFIES OFF THE COAST NEAR 130W RESULTING IN A MORE PRONOUNCED NORTHERLY FLOW OVER CA.
A COOLER AIR MASS WILL FOLLOW RESULTING IN COOLER TEMPERATURES COMPARED TO TODAY. THE MODELS ARE IN FAIRLY GOOD AGREEMENT SHOWING ANOTHER UPPER TROUGH DROPPING IN FROM B.
TEMPS SHOULD FALL BELOW FREEZING TONIGHT NORTH OF A LINE FROM ERN MCCURTAIN COUNTY. FCST SOUNDINGS ARE STRONGLY SUPPORTIVE OF FREEZING RAIN DURING THE EARLY MORNING HRS OF FRIDAY. PRECIP SHOULD TRANSITION TO ALL LIQUID RAIN BY MID MORNING FRIDAY AS THE WARM FRONT MOVES NWD AND TEMPS WARM. A FREEZING RAIN ADVISORY HAS BEEN ISSUED.
WITH SOME DRIZZLE OR FREEZING DRIZZLE AND POSSIBLE INTERMITTENT IFR CEILINGS AFFECTING NORTHWEST ARKANSAS SITES LATE IN THE FORECAST PERIOD. /ISSUED 312 PM CST THU FEB 19 2015/ THE BIGGEST ISSUE TONIGHT AND INTO FRIDAY MORNING WILL BE THE POTENTIAL FOR FREEZING DRIZZLE AND POSSIBLY FREEZING LIGHT RAIN ACROSS PORTIONS OF EASTERN OKLAHOMA AND WESTERN ARKANSAS AS MOISTURE SURGES NORTH IN ADVANCE OF AN APPROACHING STORM SYSTEM. THE POTENTIAL FOR FREEZING DRIZZLE/FREEZING LIGHT RAIN WILL EXIST MAINLY NORTH OF A FORT SMITH TO TULSA LINE. THERE IS ALSO THE POTENTIAL THAT THE PRECIPITATION WILL NOT BEGIN BEFORE THE TEMPERATURE RISES ABOVE FREEZING. THE COLD FRONT IS EXPECTED TO COME THROUGH EASTERN OKLAHOMA AND WESTERN MUCH FASTER THAT WHAT WAS THOUGHT YESTERDAY.
HIGH PRESSURE OVER THE WEST COAST WILL MAKE FOG POSSIBLE IN THE SAN JOAQUIN VALLEY EACH NIGHT INTO THE MORNING HOURS. UPPER RIDGE OVER CA REMAINS DOMINANT TODAY WITH A GENERALLY DRY AND MILD DAY ACROSS OUR AREA. THE 12Z WRF INDICATES THE RIDGE IS WILL BREAK DOWN AND SHIFT OFFSHORE TONIGHT HOWEVER. THIS WILL ALSO RESULT IN A COOLER NORTHERLY FLOW ALOFT OVER CENTRAL CA. THE MAIN IMPACT THAT THIS WILL HAVE WILL BE COOLER DAYTIME TEMPERATURES ON FRIDAY MOST NOTICEABLY OVER THE HIGHER ELEVATIONS AS HEIGHTS AND THICKNESSES LOWER. TEMPERATURES WILL CONTINUE TO TREND DOWNWARD ON FRIDAY AS THE RIDGE RE-AMPLIFIES OFF THE COAST NEAR 130W RESULTING IN A MORE PRONOUNCED NORTHERLY FLOW OVER CA.
WARMER SOUTHERLY RETURN FLOW IS ALREADY WORKING INTO THE WESTERN THIRD OF IOWA WHERE TEMPS HAVE RISEN INTO THE MID TO UPPER TEENS COMPARED TO THE SINGLE DIGITS FURTHER EAST. SOUTHERLY WINDS WILL INCREASE TONIGHT AS THE PRESSURE GRADIENT TIGHTENS BETWEEN THE DEPARTING HIGH AND AN APPROACHING TROUGH. LIGHT SNOW WILL BE DEPARTING FRIDAY MORNING AND ALTHOUGH WE WILL BE CLOUDY MUCH OF THE DAY TEMPS WILL BE WARMER THAN WHAT WE HAVE SEEN OF LATE. I DID KNOCK BACK HIGHS TOMORROW DUE TO CLOUDS THOUGH THE SW MAY BE WARMER THAN WHAT I HAVE GOING.
923 PM EST THU FEB 19 2015 A COLD PRESSURE RIDGE WILL EXTEND THROUGH THE FORECAST AREA TONIGHT AND FRIDAY.
557 PM EST THU FEB 19 2015 A COLD PRESSURE RIDGE WILL EXTEND THROUGH THE FORECAST AREA TONIGHT AND FRIDAY.
624 PM EST THU FEB 19 2015 A COLD PRESSURE RIDGE WILL EXTEND THROUGH THE FORECAST AREA TONIGHT AND FRIDAY.
LOWEST VISIBILITY AND CIGS EXPECTED OVER CENTRAL AND NORTHERN OKLAHOMA TERMINALS NORTH OF SURFACE WARM FRONT THAT IS PROGD TO SET UP NEAR THE RED RIVER.
620 PM CST THU FEB 19 2015 AT H5 LARGE CLOSED LOW OVER THE NORTHEAST CONUS SENDING FRIGID ARCTIC ACROSS THE EASTERN CONUS WITH RECORD LOWS ACROSS THE EASTERN SEABOARD. RIDGING INTO THE WESTERN CONUS WITH THE HIGH PLAINS JUST ON THE EDGE OF THE COLDEST AIR. SHOWERS TO DEVELOP ALONG THE HIGHER TERRAIN OF THE PANHANDLE IN UPGLIDE AND ISENTROPIC LIFT.
COLD FRONT WILL MOVE THROUGH TONIGHT WITH COOLER TEMPERATURES /AVERAGING 10 DEGREES LOWER/ ON FRIDAY. UPPER SHORT WAVE TROUGH WILL FOLLOW THE FRONT DELIVERING SHOWERS MAINLY TO THE BOISE/WEST CENTRAL IDAHO MOUNTAINS THROUGH FRIDAY.
VERY COLD AIR MASS OVER THE REGION WITH HIGHS TODAY ONLY IN THE LOW TO MID 40S WHICH IS MADE EVEN MORE IMPRESSIVE GIVEN THAT WE HAD AN ENTIRE DAY OF FULL SUN. ALTHOUGH THE JACKSONVILLE INTERNATIONAL AIRPORT HAS DROPPED INTO THE LOW 20S AT LEAST 10 TIMES IN THE PAST 5 YEARS (MOST FREQUENTLY IN 2010 AND 2012) THE JAX AIRPORT HAS NOT OFFICIALLY DROPPED INTO THE TEENS SINCE JANUARY 24TH 2003.
WE WILL SEE VERY LITTLE INFLUENCE FROM THE WARMER GULF AWAY FROM THE IMMEDIATE COAST. THE HIGH CENTER WILL BE WAY TO THE NORTH TONIGHT. THE AIRMASS IS COLD ENOUGH THAT WE WILL SEE A RIDGE EXTENDING SOUTHWARD ACROSS THE STATE AS COLD AIR DRAINAGE BEGINS.
The persistent ridge of high pressure over the Western US has been flattened slightly as a weak system moves through the Pacific Northwest. The aforementioned Pacific Northwest trough is expected to elongate and deepen over the Great Basin over the course of the next several days.
HIGH PRESSURE OVER ARIZONA WILL BEGIN TO WEAKEN TONIGHT AS A TROUGH OF LOW PRESSURE MOVES SOUTH OUT OF CANADA.
THIS WOULD PUT MOST AREAS AT OR BELOW THE FREEZING MARK. SO STILL EXPECT FREEZING CONDITIONS TO BE CONFINED TO THE MAINLAND THERE. NORTH/SOUTH ORIENTED HIGH PRESSURE RIDGE WILL SLIDE TO THE EASTERN SEABOARD AND CAUSE NORTHWEST WINDS TO GRADUALLY VEER TO THE NORTH LATE TONIGHT AND NORTH/NORTHEAST FRI AFTERNOON.
BUT THE WESTERN RIDGE WAS GETTING FLATTENED BY INCOMING PACIFIC ENERGY. A COLD FRONT WILL DROP IN FROM THE NORTH FRI MORNING. THE WEST COAST RIDGE THAT HAS DOMINATED MUCH OF THE WINTER APPEARS TO BE SHIFTING WESTWARD OUT INTO THE PACIFIC.
COULD STILL SEE A BRIEF PERIOD OF FREEZING DRIZZLE FRIDAY MORNING IN A FEW AREAS ACROSS NW AR/RIVER VALLEY BEFORE PRECIP TRANSITIONS TO LIGHT DRIZZLE/VERY LIGHT RAIN.
547 PM CST THU FEB 19 2015 WARM FRONT IS PRESSING EASTWARD AT THIS TIME. NOT SURE WHY TEMPERATURES WOULD PLUMMET ALL THAT MUCH WITH THIS KIND OF SOUTHERLY FLOW AND THE WARM FRONT NOT STALLING. THEREFORE TRENDED TOWARD THE WARMER READINGS WHICH WERE RAW ECMWF VALUES BLENDED WITH MOS CONSENSUS. NOW ONTO THE WARM FRONTAL SNOW. BONE DRY AIR IN THE LOW LEVELS. BEHIND THE WARM FRONT.
WITH FREEZING RAIN POSSIBLE NORTH OF A IDABEL OKLAHOMA TO EL DORADO ARKANSAS LINE. THE FREEZING RAIN SHOULD END BY 16Z AS SURFACE TEMPS WARM. THE FREEZING LEVELS ACROSS THE AREA BY THIS TIME SHOULD THEN BE AROUND 10 KFT OR HIGHER. TEMPS SHOULD FALL BELOW FREEZING TONIGHT NORTH OF A LINE FROM ERN MCCURTAIN COUNTY. FCST SOUNDINGS ARE STRONGLY SUPPORTIVE OF FREEZING RAIN DURING THE EARLY MORNING HRS OF FRIDAY. PRECIP SHOULD TRANSITION TO ALL LIQUID RAIN BY MID MORNING FRIDAY AS THE WARM FRONT MOVES NWD AND TEMPS WARM. A FREEZING RAIN ADVISORY HAS BEEN ISSUED.
/ISSUED 346 PM CST THU FEB 19 2015/ HIGH PRESSURE SYSTEM THAT HAS BEEN RIDGING DOWN INTO THE FORECAST AREA TODAY IS BEGINNING TO MOVE OFF TO THE EAST WITH LIGHT RETURN FLOW OFF THE GULF SHOWING UP OVER THE FAR SOUTHWEST ZONES. THE HIGH WILL CONTINUE TO MOVE OFF TO THE EAST WITH LOW PRESSURE DEVELOPING OVER WEST TEXAS.
810 PM MST THU FEB 19 2015 HIGH PRESSURE OVER ARIZONA WILL BEGIN TO WEAKEN TONIGHT AS A TROUGH OF LOW PRESSURE MOVES SOUTH OUT OF CANADA.
THIS AREA OF CLOUD COVER IS EXPECTED TO SHIFT EAST IN RESPONSE TO RIDGING BUILDING OVER LOUISIANA AND EASTERN TEXAS. THE SATURATION OF THE LOWEST 4000 FEET (AROUND 850 MB TO THE SURFACE) WILL TAKE LONGER. FREEZING RAIN. SOME LINGERING FREEZING RAIN.
TEMPERATURES ARE RUNNING COOLER THAN YESTERDAY AT THIS TIME IN MOST AREAS WITH READINGS RANGING FROM THE MID 50S TO THE MID 60S.
611 PM EST THU FEB 19 2015 HIGH PRESSURE WILL BE BUILDING OVER THE AREA THROUGH THE NIGHT.
TEMPS IN OUR TN COUNTIES WERE ALMOST TO THEIR FORECAST LOWS WITH OTHER AREAS SCATTERED BETWEEN THE LOWER 20S TO UPPER TEENS. A TRICKY FCST COMING UP ON FRIDAY AS A WINTER STORM WILL AFFECT THE TN VALLEY WITH A MIX OF SNOW/SLEET/FREEZING RAIN.
ESP AS LL THERMAL TROUGH IS SLOW TO BREAK DOWN TIED TO BACKING LL FLW AFT MIDNIGHT. HWVR BASED ON POSITION OF ARCTIC RIDGE AND VARIABLE BUT DEEMED SUFFICIENTLY DEEP SNOWPACK ACRS THE AREA. RECORDS ARE AS FOLLOWS: KSBN KFWA 19TH -11/1936 -7/1978 20TH -6/1929 -7/1904 ARCTIC HIGH SHIFTS OFF THE MID ATL COAST ON FRI AS H5 HGTS FLATTEN CONSIDERABLY UPSTREAM OF VIGOROUS CYCLONE LIFTING NWD UP ACRS THE CANADIAN MARITIMES.
SOME DOWNWARD ADJUSTMENTS WILL BE MADE TO TEMPERATURES OVERNIGHT FOR THE FORECAST UPDATE AS THERE ARE A FEW SPOTS THAT ARE RUNNING COOLER THAN FORECAST.
LINKED WITH A 1032 MB HIGH PRESSURE SYSTEM NEARING CENTRAL TENNESSEE. THE COLD AIR ADVECTION EXTENDS FAIRLY DEEP INTO THE LOWER TROPOSPHERE (~800MB). WATERS ARE A FEW DEGREES COOLER. LOWS WILL REACH 45-50 IN THE LOWER KEYS. AN EXPANSIVE HIGH PRESSURE SYSTEM OVER THE SOUTHEASTERN UNITED STATES WILL PERSIST THROUGH FRIDAY.
BAND OF LIGHT PRECIP AHEAD OF UPPER TROF AXIS HAS JUST MOVED INTO NW AL AND WILL CONTINUE TO PUSH EASTWARD OVERNIGHT. THE MAIN TROF AXIS SHOULD SHIFT EAST OF THE AREA BY 12Z SATURDAY MORNING WITH PRECIP COMING TO AN END. TEMPERATURES SHOULD REMAIN ABOVE FREEZING WHILE THE PRECIP IS FALLING. THE UPPER TROUGH WITH THIS SYSTEM IS FORECAST TO MOVE OVER THE AREA TONIGHT.