Aikyam-Lab/Synoptic-Bench huggingface dataset:
114 AM EDT WED MAY 4 2016 A COLD FRONT WILL CROSS THE AREA TONIGHT. DRYING WILL OCCUR BEHIND THE FRONT WEDNESDAY WITH A REINFORCING COLD FRONT CROSSING THE AREA WEDNESDAY NIGHT.
345 AM CDT WED MAY 4 2016 A weak cold front will move across the area today with little impact other than a wind shift to the north and cooler overnight temperatures tonight.
HIGH PRESSURE OVER THE REGION WILL CONTINUE TO KEEP SKIES CLEAR AND WINDS GENERALLY LIGHT OVERNIGHT. THE UPPER RIDGE WILL REMAIN IN PLACE OVER THE AREA THROUGH WEDNESDAY AND WILL CONTINUE TO PROVIDE DRY AND STABLE CONDITIONS. AN UPPER TROF WILL APPROACH THE WEST COAST WEDNESDAY AND MOISTURE AHEAD OF THE TROF, ALONG WITH INCREASING INSTABILITY, MAY ALLOW AN ISOLATED THUNDERSTORM TO DEVELOP, MAINLY ALONG THE NORTHERN ROCKY MOUNTAIN FRONT DURING THE AFTERNOON. WITH MOISTURE CONTINUING TO INCREASE AND THE AIRMASS BECOMING UNSTABLE IN THE WAKE OF A COLD FRONTAL PASSAGE, AFTERNOON THUNDERSTORMS WILL INCREASE IN AREAL COVERAGE THURSDAY AFTERNOON.
1134 PM MDT TUE MAY 3 2016 AN AMPLIFIED RIDGE OF HIGH PRESSURE WILL LINGER OVER THE AREA THROUGH MIDWEEK. OVERNIGHT LOWS WILL ALSO RUN WARMER THAN NORMAL BUT NOT BY AS MUCH AS CLEAR SKIES AND RELATIVELY DRY AIR RESULT IN STRONG RADIATIONAL COOLING. THE REGION APPEARS TO BE HEADED FOR THE WARMEST DAY OF THE YEAR ON THURSDAY AS A LOW PRESSURE CENTER APPROACHES SOUTHERN CALIFORNIA FORCING THE RIDGE AXIS TO THE EAST. THE RESULTANT SOUTHERLY FLOW WILL ADVECT WARMER AIR INTO THE REGION.
LARGE RIDGE OF HIGH PRESSURE MOVING VERY SLOWLY EAST ACROSS WYOMING KEEPING CLEAR SKIES AND RELATIVELY MILD TEMPS OVERNIGHT INTO WEDNESDAY. THIS COMPLIMENTS OF AN UPPER RIDGE THAT WILL HOLD ACROSS THE ROCKY MTN CHAIN THROUGH THURSDAY.
A LONG WAVE TROF MOVG S ACROSS N-CENTRAL TX. UPPER LVL RIDGING BEGINS BUILDING INTO THE REGION WEDNESDAY AFTERNOON. TOMORROW WILL BRING SUNNY SKIES AND MUCH WARMER TEMPERATURES. HIGHS WILL BE IN THE LOWER 80S ALONG THE COAST TO NEAR 90 DEGREES OVER THE RIO GRANDE PLAINS. LOWS TOMORROW NIGHT WILL THEN BE ONLY A FEW DEGREES WARMER.
AND TEMPERATURES WILL REMAIN COOL WITH HIGHS NO WARMER THAN THE MID 50S WITH CLOUDS AND RAIN SHOWERS.
OTHERWISE NOT A LOT OF ISSUES WITH THE FCST THE NEXT FEW DAYS AS THE UPPER RIDGE REMAINS TRAPPED BETWEEN THE TWO ROBUST LOWS ANCHORED ON BOTH U. 41 LIGHT OFFSHORE WINDS WILL CONTINUE WITH A WEAK COLD FRONT OVER OKLAHOMA TO MOVE INTO THE COASTAL WATERS THURSDAY MORNING LEADING TO A BRIEF INCREASE IN OFFSHORE WINDS.
This convection lies just ahead of a strong cold front, that is driven by a vigorous upper wave diving into the Midwest. It will be noticeable cooler across the region today behind the front, with many areas only seeing high temperatures in the 50s. Northerly post-frontal winds gusting to 30 mph at times will also make it feel cooler. Upper ridging currently along the Rockies will be edging eastward the next couple days, but pattern overall will be rather blocky, with closed lows on either side of it.
HRRR TRACKS THE RAIN AREA ENEWD OUT OF THE LOWER SUSQUEHANNA THROUGH 12Z.
108 AM CDT WED MAY 4 2016 THE WEATHER IN THE SHORT TERM PERIODS REMAIN QUIET WITH RISING HEIGHTS BEHIND A DEPARTING TROUGH AXIS. WHILE UPPER RIDGING EXPANDS EAST OF THE ROCKIES. UPPER LOW PRESSURE NEAR THE GREAT LAKES WILL TRANSLATE TO THE OHIO VALLEY REGION WEDNESDAY SETTING UP AN OMEGA BLOCKING PATTERN FOR THE MIDDLE OF THE WORKWEEK. WITH ANOTHER UPPER LOW TO THE WEST IN THE PACIFIC. OUR REGION WILL BE UNDER THE INFLUENCE OF THE UPPER RIDGE WITH A CONTINUATION OF DRY/MILD CONDITIONS. HEADING INTO WEDNESDAY HIGH TEMPS IN THE LOW/MID 70S STILL LOOK ON TRACK.
trough that has been over the region the past few days. An associated cold front will move across the region after midnight bringing a chance of showers. The lower layers of the atmosphere are relatively dry and precipitation amounts should be less than a quarter of an inch. Upper low forecast to dive south-southeast into the lower Great Lakes on Wednesday with the associated cold front and shower activity expected to be southeast of our forecast area during the morning. Seeing some occasional lightning this afternoon with the deep trof just north of Lake Superior so will continue to hold with the thunder mention, especially across the east where the temperatures aloft are the coldest.
421 AM EDT WED MAY 4 2016 COLD FRONT HAS EXITED THE CWA THIS MORNING. CLOSED UPPER TROUGH WILL IMPACT THE AREA THROUGH THURSDAY. WITHIN TOLERANCE BUT ON THE LOW SIDE COMPARED TO THE NEIGHBORS AND THIS MAY BE A BIT TOO CONSERVATIVE IF THE CONVECTION DOES TAKE ON A MORE ORGANIZED LINEAR FORM. AS CLOSED TROUGH SPINS OVER THE CAROLINAS THURSDAY. 31 UPPER CLOSED LOW CIRCULATING OVER THE MID ATLANTIC STATES AT THE START OF THE PERIOD.
404 AM CDT WED MAY 4 2016 (Today and Tonight) Upper ridge will build east over western Texas through tonight with a resultant northwest flow aloft over the forecast area. Mostly clear skies and dry conditions are on tap for the forecast area with afternoon highs warming into the lower 80s area-wide. Morning lows tomorrow will be in the the low to mid 50s.
HIGH PRESSURE WITH ISOLABAIC MAXTO ARRIVE MID MORNING WITH COOLER AND DRIER AIR AND STRENGTHENING NORTHERLY WINDS. SURFACE AND UPPER HIGH PRESSURE TO DOMINATE THE NEXT 3 DAYS BRINGING FAIR SKIES AND DRY CONDITIONS WITH WARMING TREND STARTING THURSDAY.
UPPER LEVEL TROUGH SET TO DIG FURTHER SOUTH TODAY AND USHER IN COLDER AIR. BRIEF CLEARING LATE THIS MORNING BEFORE NEXT ROUNDS OF CLOUDS MOVE IN EARLY/MID AFTERNOON IN ADVANCE OF COLD FRONT. FREEZING HEIGHTS WILL LOWER THROUGH THE AFTERNOON HOURS WHICH WILL ALLOW FOR SMALL HAIL DUE TO THE COLD AIR ALOFT. FROM 21Z TO 00Z WILL BE WHEN THE HIGHEST PRECIP CHANCES ARE IN PLACE AS IT COINCIDE WITH THE BEST UPPER LEVEL DIVERGENCE. PROXIMITY TO CENTER OF THE LOW PRESSURE. LOCALLY HIGHER AMOUNTS POSSIBLE ON THE HIGHEST PEAKS. BREEZY NW WINDS AND UNSEASONABLE COLD TEMPERATURES WILL GIVE BELOW FREEZING APPARENT TEMPERATURES. APPARENT TEMPS AROUND 3000 FEET WILL BE NEAR FREEZING. AND DOWN INTO THE LOW 20S ONCE YOU GET ABOVE 4500 FEET.
ASSOCD WITH AN UPR TROF WORKING THRU THE REGION. ANOTHER UPR TROF/CDFNT WL DROP SWD THRU THE FA LATER TODAY AND EARLY TNGT. WITH HIGHS MAINLY IN THE LOWER AND MID 70S.
WILL MOVE INTO THE UPPER RIDGE THIS AFTERNOON. LOOKING AT A MOSTLY SUNNY AND VERY WARM DAY TODAY WITH TEMPERATURES IN THE LOWER TO MID 80S DUE TO MIXING TO ABOVE 700 MB WHERE TEMPERATURES WILL BE AT LEAST +6 DEGREES C. UPPER RIDGE REMAINS IN THE PLACE ON THU AND STARTS SHIFTING E THU NIGHT. THIS WILL COMBINE WITH A COLD FRONT MOVING IN FROM THE NW TO BRING LOW CHANCES FOR EVENING THUNDERSTORMS AND OVERNIGHT SHOWERS TO THE NW PART OF THE AREA.
A NORTHWESTERLY TO NORTHERLY WIND FLOW, GUSTY AT TIMES TODAY, WILL USHER IN A COOLER AND DRIER AIRMASS. THE COLD FRONT WHICH PUSHED THROUGH THE FORECAST AREA IS NOW WELL EAST APPROACHING THE BIG BEND AREA OF FLORIDA. OVERNIGHT LOWS SHOULD BE CONSIDERABLY COOLER THAN WHAT WE'VE EXPERIENCED LATELY WITH INLAND SITES FALLING INTO THE LOW TO MID 50S WITH GENERALLY MID TO UPPER 50S NEARER THE COAST.
/ISSUED 345 AM CDT WED MAY 4 2016/ A weak cold front will move across the area today with little impact other than a wind shift to the north and cooler overnight temperatures tonight.
UPPER TROUGH NEAR THE WEST COAST HAS BEGUN TO SPLIT. WITH THE SOUTHERN PORTION OF THE TROUGH TRANSITIONING TO A CLOSED UPPER LOW OFF THE CALIFORNIA COAST. BETWEEN THE TROUGH TO THE WEST AND A HIGH-AMPLITUDE RIDGE TO THE EAST. TEMPERATURES WILL BE EVEN WARMER TODAY. THE LEADING EDGE OF THE MOISTURE ASSOCIATED WITH THE TROUGH WILL RESULT IN ISOLATED SHOWERS IN SE OREGON THIS MORNING. AS THE TROUGH SHIFTS SLIGHTLY EAST. THE TROUGH/UPPER CLOSED LOW WILL BE SLIGHTLY CLOSER ON THURSDAY. ESPECIALLY IN SE OREGON AND IN THE HIGHER TERRAIN OF SW IDAHO. TEMPERATURES WILL REMAIN WARM IN SW IDAHO BUT SLIGHTLY COOLER IN SE OREGON ON THURSDAY.
657 AM EDT WED MAY 4 2016 RAIN WILL RETURN TO THE AREA TODAY AS ANOTHER COLD FRONT SWEEPS THROUGH THE REGION.
418 AM CDT WED MAY 4 2016 Current satellite imagery and surface obs show a weak cold front moving through the Midwest. Surface temperatures warmed into the upper 50s ahead of the cold front, but will drop into the upper 40s to low 50s once the front passes through. A few cumulus clouds will be possible today and with decent mixing of the lower levels, temperatures should quickly rebound with highs in the mid and upper 60s. Upper level ridge positioned over the inter-mountain west and High Plains will dominate the weather through the remainder of the work week before breaking down as a large trough moves onshore and into the Great Basin.
THE CLOSED LOW PRESSURE MAY STILL BE LOCATED OFF CENTRAL CALIFORNIA COAST BUT ITS REACH WILL BE FELT INTO SOUTHERN OREGON. ON THURSDAY THE CLOSED LOW IS FORECAST TO COME ASHORE OVER CENTRAL CALIFORNIA. CONFIDENCE ON THE TRACK OF THIS LOW IS NOT VERY HIGH DUE TO THE NATURE OF THE CLOSED LOW IN GENERAL.
HIGH PRESSURE WILL BRING A WARMING TREND THROUGH MIDWEEK. THE NEXT PACIFIC TROUGH WILL ADVANCE INTO THE GREAT BASIN LATE IN THE WEEK.
WITH THE BARELY DISTINGUISHABLE COLD FRONT FAR DOWN IN THE FLORIDA PANHANDLE, CALM CONDITIONS ARE EXPECTED FOR THE MORNING WITH MODEST TEMPS IN THE UPPER 50S. LATER IN THE AFTERNOON A SLIGHT BURST OF UPPER JET ENERGY WILL INSTIGATE A SHORT WAVE TROUGH TO ROUND THE CURRENT EAST CONUS LONGWAVE AND SWEEP THROUGH THE TENNESSEE VALLEY AND BRING A FEW BRIEF SHOWERS INTO THE REGION DURING THE EVENING HOURS AROUND 4-6PM. SURFACE TEMPS ARE ONLY EXPECTED TO REACH LOW 70S AT THE HIGHEST DUE TO THE RAIN AND SOME PERSISTENT MIDDAY CLOUD COVER.
CLOUDY AND COOL TODAY AS AN UPPER LOW APPROACHES AND PRODUCES SOME NORTH BAY SHOWERS. CHANCE OF SHOWERS CONTINUES OVERNIGHT INTO THURSDAY ALONG WITH A ISOLATED THUNDERSTORMS AS THE UPPER LOW WOBBLES AROUND THE CENTRAL COAST.
359 AM MDT WED MAY 4 2016 CLEAR SKIES PREVAIL ACROSS THE REGION AS A MID LVL RIDGE LIES JUST TO OUR WEST. WITH 20S AND 30S ACROSS THE HIGHER ELEVATIONS. EXCEPT FOR SOME LIGHT ISOLD -TSRA OVER THE HIGHER MTN TOPS. SFC WINDS WILL BE DIURNALLY DRIVEN RIDGE ALOFT WILL MOVE OVER THE REGION. AND 20S AND 30S ACROSS THE HIGHER TRRN.
243 AM EDT WED MAY 4 2016 COOL LOW PRESSURE WILL KEEP SHOWERS IN THE FORECAST THROUGH THURSDAY.
THIS EVENING THROUGH WEDNESDAY NIGHT 1930Z WATER VAPOR ANALYSIS REVEALS HIGH AMPLITUDE RIDGE WEST OF THE CWA. WESTERN CONUS RIDGE SLOWLY SLIDES TOWARD THE CWA TONIGHT AND TOMORROW. WARMER AIR ALOFT WILL ADVECT INTO THE REGION WEDNESDAY AND RESULT IN AFTERNOON HIGHS BEING ABOUT 5 DEGREES WARMER ON WEDNESDAY COMPARED TO TODAY.
129 AM EDT WED MAY 4 2016 AN UNSETTLED WEATHER PATTERN WILL REMAIN ACROSS CENTRAL NY AND NORTHEAST PA THROUGH THE END OF THE WEEK AS AN UPPER LEVEL LOW DROPS SOUTHEAST AND COVERS THE MIDDLE ATLANTIC STATES AND THE NORTHEAST. THERE WAS ALSO SOME PATCHY DENSE FOG REPORTED OVER THE HIGHER TERRAIN IN THE POCONOS.
350 AM CDT WED MAY 4 2016 UPPER LEVELS SHOW AN AMPLIFIED RIDGE ACROSS THE ROCKIES WITH A TROUGH ACROSS THE GREAT LAKES REGION. RIDGE EXPANDS ACROSS THE AREA TODAY WITH THE CONTINUED WARM UP. WITH GUIDANCE FOLLOW WHICH PUTS HIGHS INTO THE LOWER TO MID 70S. A LITTLE COOLER ACROSS NORTH CENTRAL. WITH LOWS IN THE LOWER TO MID 40S EXPECTED.
/TODAY/ LITTLE SENSIBLE WEATHER TODAY AS THE OVERNIGHT SYSTEM DEPARTS TO THE EAST AND HIGH PRESSURE MOVES IN FROM THE NORTHWEST. THE STATE WILL BE IN THE THERMAL TROUGH IN THE WAKE OF THE OVERNIGHT COLD FRONT AND WEAK COLD ADVECTION WILL CONTINUE INTO THIS MORNING.
HIGHS ION WEDNESDAY WILL BE ON THE COOL SIDE WITH READINGS IN THE LOWER 70S EAST TO 60/65 WEST. A HIGH AMPLITUDE RIDGE IN-BETWEEN. PATTERN TRANSITION WILL TAKE PLACE WEDNESDAY AND WEDNESDAY NIGHT AS A COLD UPPER LEVEL TROUGH SINKS SOUTH FROM HUDSON BAY REGION THROUGH THE GREAT LAKES AND OHIO VALLEY. THIS TROUGH WILL CUTOFF OVER THE MID ATLANTIC THURSDAY.
258 AM CDT WED MAY 4 2016 TRANQUIL WEATHER PATTERN WILL CONTINUE THROUGH THE PERIOD AS UPPER RIDGE DOMINATES ACROSS THE REGION.
COOLER AND DRIER AIR WAS ALREADY FLOWING INTO THE REGION.
WE/VE CLEARED OUT NICELY IN THE WAKE OF THE PASSING COLD FRONT. MUCH COOLER 50S TODAY. COOLER EAST THAN WEST. THE RIDGE AXIS IS WEST OF OUR AREA.
HIGH TEMPERATURES WILL BE A BIT WARMER WITH HIGHS IN THE 80S FOR MUCH OF THE AREA.
333 AM EDT WED MAY 4 2016 A COLD FRONT CROSSING THE MIDLANDS EARLY THIS MORNING WILL MOVE OFF THE COAST BY SUNRISE. A COOLER AND DRIER AIRMASS WILL OVERSPREAD THE REGION TODAY. A REINFORCING COLD FRONT WILL CROSS THE AREA TONIGHT.
315 AM CDT WED MAY 4 2016 Upper ridge extending northward over the Rockies this morning will build east the next few days. However the next upper trough will move ashore the CA coast on Thursday becoming a cut off low. This low will wobble east before lifting northeast into the Central Plains. This low may bring storms to the region this weekend. High pressure and mild wx returns after that. Wind should be light and mainly northerly today coming back around to the south overnight as a new leeside trough sets up.
WEDNESDAY WILL FEATURE DRY NORTHWEST FLOW ALOFT WITH A SHARP UPPER LEVEL HIGH PRESSURE RIDGE EDGING INTO THE CENTRAL AND SOUTHERN ROCKIES. RMCQUEEN UPPER RIDGING WILL KICK OFF THE EXTENDED.
343 AM MST WED MAY 4 2016 STRONG HIGH PRESSURE WILL LEAD TO VERY WARM TEMPERATURES TODAY WITH MANY LOWER DESERT LOCATIONS REACHING 100 DEGREES. A COOLING TREND STARTS THURSDAY AS A LOW PRESSURE SYSTEM BEGINS MOVING INTO THE SOUTHWEST.
UPPER LEVEL TROUGH WILL MOVE ACROSS THE CENTRAL PLAINS WITH A REINFORCING HIGH PRESSURE AT THE SURFACE MAKING IT THROUGH THE CWA EARLY THIS MORNING. RIDGE BEGINS TO BUILD RETURNING NORTHERLY FLOW ALOFT BREAKING THE OVC TO BKN CLOUD DECK BY THIS AFTERNOON. THURSDAY RIDGE BUILDS MOVES FURTHER EAST INTO THE CENTRAL PLAINS WITH MUCH DRIER AIR MOVING INTO THE AREA. TEMPERATURES THURSDAY WILL BE MUCH WARMER REACHING THE MID 90S OUT WEST AND LOW 90S NEAR THE COAST.
AN UPPER LEVEL LOW WILL CONTINUE ITS TRACK THROUGH THE GREAT LAKES REGION TODAY AND EVENTUALLY SETTLE IN THE OHIO VALLEY BY TOMORROW. A LARGE RIDGE OF HIGH PRESSURE WILL CONTINUE TO STRENGTHEN OVER THE CENTRAL U.
CONCUR WITH THE GFS DETERMINISTIC WHICH DEVELOPS AN OMEGA BLOCK PATTERN BY THURSDAY OVER THE CONUS WITH THE CWA/MSA UNDER THE SUBSIDENT SECTOR EAST OF THE RIDGE AXIS. EXTENDED BEGINS WITH WARM AND DRY WEATHER ACROSS THE COASTAL BEND WITH RIDGING AT THE SURFACE AND ALOFT.
147 AM EDT WED MAY 4 2016 WEAK HIGH PRESSURE OVER THE AREA WILL DRIFT SOUTHEAST TONIGHT. LOW PRESSURE WITH AN ASSOCIATED COLD FRONT WILL DROP SOUTH INTO THE REGION ON WEDNESDAY. THE LOW PRESSURE AREA WILL MAKE SLOW PROGRESS TO THE EAST ON THURSDAY. HIGH PRESSURE WILL BUILD IN FOR THE END OF THE WEEK. CLOUDS FROM THE APPROACHING COLD FRONT ARE MOVING ACROSS LOWER MICHIGAN AND SHOULD ARRIVE OVERNIGHT. MODELS ARE IN GOOD AGREEMENT IN THE PROGRESSION OF THE UPPER SYSTEM SOUTH WITH ITS ASSOCIATED COLD FRONT AND DEVELOPMENT OF SURFACE CYCLOGENESIS OVER OHIO. HAVE GONE COOLER THAN GUIDANCE IN THE NORTH NEAR COOL LAKE ERIE AS A NORTHERLY FLOW WILL PERSIST AFTER THE SYSTEM SHIFTS TO THE EAST.
FRONT HAS PUSHED WELL OFFSHORE INTO THE GULF AND COOLER. DRIER AIR IS FILTERING INTO THE AREA AS A LONG WAVE TROUGH DIGS INTO THE SOUTHEAST. NOT MUCH TO SPEAK OF AS WE MOVE THROUGH THE WORK WEEK AS HIGH PRESSURE SETTLES OVER THE AREA.
234 AM EDT WED MAY 4 2016 RAIN WILL RETURN TO THE AREA LATE TONIGHT AS ANOTHER COLD FRONT SWEEPS THROUGH THE REGION.
STRONG HIGH PRESSURE ALOFT WILL BRING HOTTER TEMPERATURES TODAY.
143 AM EDT WED MAY 4 2016 WEAK HIGH PRESSURE WILL BUILD OVER THE REGION TODAY WITH GRADUAL CLEARING FROM WEST TO EAST THROUGH THE EVENING. AN UPPER LEVEL LOW WILL DROP SOUTHWARD FROM THE GREAT LAKES WHICH WILL SERVE TO BE THE FORCING FOR SOME LIGHT RAIN AND SHOWERS WEDNESDAY. WITH THAT WARMING OVERNIGHT EXPECT A MORE MILD EVENING THIS EVENING WITH OVERNIGHT LOWS IN THE LOW 40S ACROSS THE NORTH COUNTRY.
A SLIGHT COOL DOWN IN THE WAKE OF A COLD FRONT THAT MOVED ACROSS THE NORTHLAND TODAY. ACROSS THE MINNESOTA ARROWHEAD AND INTO NORTHWEST WISCONSIN ELEVATED INSTABILITY IN THE WAKE OF A COLD FRONT HAS LEAD TO SOME SCATTERED SHOWERS AND THUNDERSTORMS. AS UPPER LEVEL RIDGING BEGINS TO BUILD INTO THE UPPER MIDWEST WEDNESDAY NIGHT. THE UPPER RIDGE PUSHES FARTHER EASTWARD ON THURSDAY.
HIGH TEMPERATURES ARE EXPECTED TO BE 5 TO 8 DEGREES WARMER TODAY AS COMPARED TO YESTERDAY UNDER MOSTLY CLEAR SKIES AS THE UPPER RIDGE AXIS NEARS THE AREA. WARMING CONTINUES ON THURSDAY WITH HIGH TEMPERATURES TOPPING OUT IN THE LOW TO MIDDLE 80S.
A HIGH AMPLITUDE PATTERN OVER THE US LEAVES WEAK COLD AIR FOLLOWED BY SHARP UPPER RIDGING AND LIGHT EASTERLY WINDS OVER THE AREA THURSDAY.
628 AM EDT WED MAY 4 2016 SHOWERS AND POSSIBLY A THUNDERSTORM WILL LINGER ACROSS THE AREA TODAY AHEAD OF AN APPROACHING COLD FRONT.
ZONAL FLOW ALOFT WILL BEGIN TO SHIFT NORTHWEST AS UPPER TROUGH OVER NORTH CENTRAL PLAINS DIGS SOUTH AND MOVES ACROSS THE REGION. THIS WILL EVENTUALLY CLEAR SKIES ACROSS DEEP SOUTH TEXAS AND THE LOWER VALLEY TERMINALS. HIGH PRESSURE BUILDS SOUTH IN WAKE OF A MID LEVEL LOW PRESSURE TROUGH PASSING EAST OF DEEP SOUTH TEXAS BY SUNRISE WEDNESDAY. A 500 MB TROUGH AXIS OVER THE CENTRAL PLAINS STATES WILL MOVE THROUGH THE REGION LATER TONIGHT THROUGH WED MORNING. THE PASSAGE OF THIS TROUGH AXIS WILL FINALLY PUSH OUT THE LAST OF THE LOW CLDS OVER THE RGV ALLOWING FOR MOSTLY CLR SKIES TO PREVAIL WED AND WED NIGHT.
Clouds have continued to thicken across NorCal overnight as moisture flows up from the south ahead of the offshore trough - now inside of 130W. Approaching trough is splitting, with the southern end forming a closed low off the central California coast.
A COLD FRONT IS BACK-DOORING ITS WAY THROUGH THE EASTERN CWA. THE TYPICAL COOLER. THE REST OF THE SHORT TERM THROUGH THURSDAY NIGHT WILL BE DRY WHILE SURFACE AND UPPER LEVEL HIGH PRESSURE EXERTS INFLUENCE OVER THE REGION. ONLY ABOUT 10 TO 15 DEGREES WARMER. WITH A RIDGE OVER THE CENTRAL CONUS TO START. RETURN FLOW AHEAD OF THIS FEATURE WILL PUSH 850MB TEMPERATURES INTO THE LOW 20S CELSIUS.
HIGH PRESSURE WILL BRING DRY CONDITIONS THROUGH THIS MORNING. LOW PRESSURE WILL ENSURE ABUNDANT SHOWERS OCCUR THIS WEEKEND.
A lobe of upper level energy swinging around the southwest flank of a closed H5 low over the Great Lakes region will push a cold front across the region this morning. With the freezing level being so low combined with favorable lapse rates, small hail will be possible in a few of the stronger showers/thunderstorms. The upper low is forecast to drop south southeastward along the IN/OH border this afternoon so small chances for showers and thunderstorms are possible over the eastern third of our CWA. Precipitation chances will end by late afternoon as the upper low slips off to the southeast of the region. Beyond that rising heights aloft and high pressure at the surface should keep the region dry with slowly moderating temperatures.
1033 AM MST Wed Dec 7 2016 Upper level analysis has large trof over most of the CONUS with closed low over northern MN. Frigid air will continue to push into the area as Arctic high pressure settles into the Northern Plains. Lows late tonight will plummet well below zero in most locations as Arctic high pressure center slides into western portions of the area. Arctic high pressure moves across the Dakotas on Thursday.
1212 PM MST Wed Dec 7 2016 Current surface analysis shows strong low pressure now over southern Ontario, with 1045 mb high over southern Alberta. Large upper level trof now covers much of Canada and the United States today, with strong jet stretching from the pacific NW to the Southern Plains to the northeast US. Upper level analysis has large trof over most of the CONUS with closed low over northern MN. Frigid air will continue to push into the area as Arctic high pressure settles into the Northern Plains. Lows late tonight will plummet well below zero in most locations as Arctic high pressure center slides into western portions of the area. Arctic high pressure moves across the Dakotas on Thursday.
130 PM EST Wed Dec 7 2016 High pressure will build over the region through mid week.
249 PM EST Wed Dec 7 2016 A trough of low pressure will result in a return to cold temperatures and periodic snow showers through the end of the week.
850 mb temps begin to warm just slightly over the west as the ridge axis moves eastward on Thursday morning.
Forecast generally on track under cooler northerly flow. Satellite imagery and surface observations continue to show a solid deck of low stratus extending across our region, keeping early morning temperatures a little warmer than expected, with readings in the lower to mid 50s as of 3 A. The low stratus deck is expected to hold strong this morning, and may linger into the afternoon though there could be some breaks of sun. High temperatures today should only reach the lower to mid 60s over most places, except in the upper 50s to around 60 across locations generally north of the U. Lows tonight remain cool, with readings in the lower to mid 40s over interior areas and upper 40s to lower 50s closer to the coast and beaches.
Lows tonight will range from the low 50s over far northern Lake/Volusia Counties to mid 60s with more clouds over Martin County. High temperatures ranging from the lower 70s north to upper 70s south. Deeper moisture will move in across srn sections with mid level ascent behind the cold front that will have moved through south FL. The pressure gradient will tighten as high pressure builds into the Southeast with gusty northerly winds along the coast and lows ranging from the upper 40s/lower 50s north to lower 60s across Martin county.
There will be some weak ascent develop ahead of the trough across central and southern Missouri into southern Illinois. The upper trough will move quickly east tonight. With the clouds and cold air advection, went with highs closer to the cooler SREF mean temperatures today. Lows tonight will be closer to the cooler MAV MOS lows.
Additional accumulations should be no more than a couple of inches at the high side over main NW MN.
1129 AM CST Wed Dec 7 2016 A low level thermal trough over the area continues to keep an elevated inversion in place. This low stratus deck should mix out a bit over KGPT, and have VFR conditions at this terminal through the evening hours.
122 PM EST Wed Dec 7 2016 An approaching cold front will move through the forecast area Thursday.
1225 PM EST Wed Dec 7 2016 Building high pressure should maintain dry weather today. A Thursday cold front will bring much colder temperatures and snow shower chances to end the work week. Building high pressure should maintain partly cloudy skies across the area this afternoon. Very little moisture exists along the mid-level cold front, so initial precipitation chances will be minimal through Thursday afternoon, but a slight wind shift will bring lake-effect and upslope snow that could extend into the early weekend. Although cold advection will be ongoing, the coldest air will pour in later Thursday afternoon with a mid-level trough. Veering winds behind the trough axis will seep Great Lakes moisture in across the northern 1/3 of the forecast area, eventually extending southward into the Ridges.
in addition to the lowest vsby/cigs. Rain chances will increase this evening as an arctic cold front moves into the ArkLaTex region. Any lingering fog will scour out by mid-morning, but as sfc winds veer to the east southeast /upslope component/, the low cloud cover will persist and subsequently, so will bouts of drizzle/light rain. This evening-tonight, a longwave trough will move from the Rockies onto the Plains and will send a breezy cold front across the region /15-20 mph especially across far east TX which is nearing Lake Wind Advisory criteria/.
A warm front moves into the Great Basin tonight at the leading edge of a moist and fairly mild westerly flow developing in the Pac. Mid and high clouds increase tonight across UT ahead of the warm front with the front itself arriving Thu aftn.
228 PM EST Wed Dec 7 2016 High pressure builds into the area tonight. A cold front will move through the Mid Atlantic Thursday evening.