Aikyam-Lab/Synoptic-Bench huggingface dataset:
A LOW PRESSURE SYSTEM DROPPING OUT OF THE GULF OF ALASKA WILL PROVIDE THE POTENTIAL FOR AN UNSETTLED AND COOLER WEATHER PATTERN BY MIDWEEK. WEAK TROUGHING ACROSS THE EASTERN PACIFIC PERSISTS TODAY AND WILL PROVIDE WARM CONDITIONS WITH A CHANCE FOR SHOWERS AND THUNDERSTORMS MAINLY ACROSS SOUTHERN LYON COUNTY INTO MONO AND MINERAL COUNTIES. BY MONDAY THE UPPER LEVEL PATTERN BEGINS TO BECOME MORE PROGRESSIVE AS A CLOSED LOW OVER THE GULF OF ALASKA HELPS PUSH THE STALLED TROUGH ACROSS THE WEST COAST.
227 AM EDT SUN MAY 3 2015 A LARGE RIDGE OF HIGH PRESSURE WILL GRADUALLY MOVE OFF THE COAST TODAY.
343 AM CDT SUN MAY 3 2015 HIGH PRESSURE AT SFC AND ALOFT KEEPING SKIES MOSTLY CLEAR FOR THE NEXT COUPLE OF DAYS ASIDE FROM CONTINUED AFTN CUMULUS. AS DIFFUSE UPPER TROUGH OVER FOUR CORNERS TAKING ITS TIME ORGANISING.
103 AM EDT SUN MAY 3 2015 AVIATION FAIR WEATHER WILL CONTINUE INTO SUNDAY EVENING WHEN A COLD FRONT WILL BRING SOME SHOWERS AND THUNDERSTORMS. FAIR WEATHER EXPECTED AS SFC RIDGING MOVES EAST. BY SUNDAY EVENING GOOD MOISTURE TRANSPORT AND A 35 TO 40 KT LLJ ARRIVES AHEAD OF APPROACHING COLD FRONT.
THIS WILL NOT BE THE CASE AS MUCH GOING INTO MONDAY AS A NORTHERN CLIPPER TROUGH WEAKENS THE UPPER RIDGE OVER THE GULF SOUTH.
420 AM EDT SUN MAY 3 2015 HIGH PRESSURE WILL BRING DRY AND WARM WEATHER TODAY. LEANED A BIT TOWARDS THE WARMER SIDE OF GUIDANCE. ALLOWED TO INVADE BY THE CONTINUING SMOOTHING OF THE RIDGE. WELL ABOVE NORMAL TEMPERATURES WILL BE THE HIGHLIGHT THROUGH THE EXTENDED AS RIDGING REMAINS IN PLACE ACROSS THE EASTERN STATES.
A STRONG THERMAL RIDGE AXIS WILL PUSH INTO THE WESTERN GREAT LAKES AHEAD OF AN ADVANCING TROF UPSTREAM. RESULTING IN MANY LOCATIONS HITTING THE LOWER 80S. WE WILL SEE THE LOW LEVELS DRY OUT TOO MUCH WITH DEEP MIXING AND THIS SHOULD KILL OUR CHANCES FROM LATE MORNING THROUGH AT LEAST MID AFTERNOON. THE SOUNDINGS OVERALL LOOK DRY TODAY AHEAD OF THE TROF. THE MAIN FOCUS CONTINUES TO BE THE APPROACHING TROF/COLD FRONT FOR THIS EVENING AND OVERNIGHT. THE TROF IS WEAKENING ALONG WITH THE LOW LEVEL JET AND DEEP LAYER SHEAR.
340 AM EDT SUN MAY 3 2015 HIGH PRESSURE OFFSHORE WILL BRING A SOUTHERLY FLOW OVER THE NORTHEAST AND TRANSPORT WARMER AIR INTO THE AREA.
144 AM EDT SUN MAY 3 2015 HIGH PRESSURE WILL BRING DRY AND WARM WEATHER THROUGH THE WEEKEND. AND PARTICULARLY IN THE VALLEYS AMONGST THE RIDGES. ESPECIALLY BETWEEN THE CHESTNUT AND LAUREL RIDGES AS WELL AS IN THE LOWER SPOTS OF GARRETT COUNTY. TEMPERATURES ARE FORECAST TO BE WARMER THAN NORMAL IN LIEU OF THE WARM AIR DISPLACEMENT THROUGH THE PERIOD. ARE FORECAST TO PERSIST THROUGH THE LATTER HALF OF THE WEEK AS A CLOSED LOW IS PROJECTED OVER THE GREAT BASIN WITH RIDGE INFLATION ACROSS THE EASTERN CONUS.
Monday looks to be the warmer of the two, with high temperatures in the 70s and potentially 80s for some valley locations.
HIGH PRESSURE RIDGE ALONG THE EASTERN SEABOARD WILL PUSH OFFSHORE. EASTERLY LOW LEVEL WINDS WILL INCREASE AS HIGH PRESSURE ALONG AND OFFSHORE THE MID ATLANTIC COAST STRENGTHENS. PRESSURE GRADIENT TIGHTENS INTO EARLY THIS WEEK BETWEEN HIGH PRESSURE RIDGE TO THE NORTH AND LINGERING WEAK FRONTAL BOUNDARY SOUTH OF FLORIDA. WHILE THE GFS SHOWS FASTER FORMATION OF THE LOW AND HINTS AT POTENTIAL FOR SUBTROPICAL DEVELOPMENT WELL OFFSHORE LATER IN THE WEEK. PRESSURE GRADIENT HAS EASED ACROSS THE NORTHERN WATERS AS HIGH PRESSURE RIDGE AXIS SETTLED CLOSER TO THE AREA. THIS IS TEMPORARY THOUGH AS HIGH PRESSURE WILL STRENGTHEN TODAY AND TONIGHT.
250 AM EDT SUN MAY 3 2015 HIGH PRESSURE THIS WEEKEND. HIGH PRESSURE DRIFTS TO THE MID ATLANTIC COAST. ANOTHER WEAK AND DRY TROUGH AXIS ALOFT MAY BRING SCATTERED MID LEVEL MOISTURE/CLOUDS TO THE TUG FORK VALLEY.
WESTERLIES REMAIN FAIRLY FLAT ACROSS THE WESTERN AND CENTRAL STATES WHILE A WEAK/BROAD MID LEVEL TROUGH MOVES ACROSS SOUTHWESTERN CANADA. DEVELOPING ACROSS CENTRAL NEBRASKA ALONG THE TROUGH AXIS AND SHIFTING EAST FOR A FEW HOURS BEFORE DISSIPATING BY 06Z. THE SFC BOUNDARY WILL SLOW AS IT MOVES TOWARD THE KS/NE BORDERS AND EVENTUALLY STALL EARLY MONDAY BEFORE SHIFTING NORTH AS A WARM FRONT MONDAY NIGHT INTO SOUTHEAST NEBRASKA/NORTHWEST MISSOURI. CONVECTION IS QUITE LIKELY ALONG THIS BOUNDARY WITH HEAVY RAIN QUITE POSSIBLE AS THETA-E RIDGE AXIS SHIFTS INTO THE REGION AND PW'S INCREASE TO NEAR 2.
652 AM EDT SUN MAY 3 2015 HIGH PRESSURE ACROSS THE MID ATLANTIC REGION WILL ALLOW A CONTINUED WARMING TREND FOR THE REGION TODAY. WARMER START THIS AM AND 925MB AFTN TEMPS ON ORDER OF ABOUT 3C WARMER SUPPORTS MODICUM OF INCRS IN ALREADY WARM/WELL ABOVE NORMAL PRIOR FCST.
517 AM EDT SUN MAY 3 2015 HIGH PRESSURE OVER THE SOUTHERN APPALACHIANS WILL DRIFT EAST AND OFF THE CAROLINA COAST TONIGHT. A DEVELOPING SOUTHWESTERLY FLOW WILL LEAD TO WARMER TEMPERATURES THAT WILL CONTINUE THROUGH AT LEAST THE MIDDLE OF THE UPCOMING WEEK. A RIDGE OF HIGH PRESSURE EXTENDING NORTH/SOUTH ACROSS THE SUSQ VALLEY WAS PROVIDING VERY LIGHT AND VARIABLE WIND. TEMPS WILL FALL ANOTHER 2 OR 3 DEG F OVER THE NEXT FEW HOURS WITH MINS AT SUNRISE VARYING FROM THE LOW-MID 30S ACROSS THE NW MTNS. TO 45-50F IN THE LOWER SUSQ VALLEY. WHERE MDLS POOL LL MOISTURE IN VICINITY OF OLD SFC TROF.
BUT WARMER BOUNDARY LAYER TEMPERATURES SO WE MAY SEE A JUMP OF A DEGREE OR TWO FROM YESTERDAY.
A SUNNY AND MAINLY DRY DAY WILL BE IN STORE FOR THE REGION WITH AN UPPER-RIDGE SLOWLY BUILDING IN FROM THE SOUTHWEST. WHICH COMBINED WITH THE SUN WILL MAKE FOR AN EVEN WARMER DAY TODAY. RIDGE OF HIGH PRESSURE CONTROLS OUR WEATHER THROUGH THE PERIOD WITH HIGHS RANGING FROM 5 TO 8 DEGREES ABOVE NORMAL. AN AREA OF LOW PRESSURE LOOKS TO COME ONSHORE INTO THE CAROLINAS. CHATTANOOGA AIRPORT, TN 80 56 81 57 / 0 0 10 0 KNOXVILLE MCGHEE TYSON AIRPORT, TN 78 55 80 57 / 0 0 10 0 OAK RIDGE, TN 77 54 80 56 / 0 0 10 0 TRI CITIES AIRPORT, TN 74 50 78 53 / 0 0 10 10.
401 AM EDT SUN MAY 3 2015 HIGH PRESSURE BUILDS OVER THE AREA OVERNIGHT.
UPDATE COLD FRONT NEARLY THROUGH THE JAMES RIVER VALLEY. CURRENT SURFACE ANALYSIS PLACES COLD FRONT PUSHING THROUGH NORTH CENTRAL INTO WESTERN NORTH DAKOTA WHILE SHOWERS AND THUNDERSTORMS FIRE UP NEAR A PRE-FRONTAL TROUGH PUSHING OVER NORTHEAST INTO SOUTH CENTRAL NORTH DAKOTA. UPPER LEVEL ANALYSIS PLACES WEAK SHORT WAVE SLIDING THROUGH WEST/SOUTHWEST FLOW AHEAD OF A LOW AMPLITUDE TROUGH PUSHING TO THE EAST OF THE ROCKIES. QUIET WEATHER EXPECTED IN THE WAKE OF THE COLD FRONT BRINGING NORTHWEST WINDS AND DRY CONDITIONS. ATTENTION THEN SHIFTS TO A LARGE TROUGH /H5 LOW WHICH WILL MOVE INTO THE WESTERN UNITED STATES. AHEAD OF THE LOW.
WEAK HIGH PRESSURE WILL BUILD SLOWLY INTO OUR REGION FROM THE WEST THROUGH THE WEEKEND. THE HIGH WILL MOVE OFF THE COAST ON MONDAY WITH SOUTHERLY RETURN FLOW BRINGING ABOVE NORMAL TEMPERATURES FOR THE UPCOMING WORK WEEK.
Clear skies continue tonight but temperatures will not be as cold, with overnight lows in the lower and middle 30s.
WITH NUMEROUS ONLY AT THE RIDGETOPS. THE STRONG RIDGE THAT IS BUILDING AHEAD OF A DEVELOPING PACIFIC TROUGH WILL SPREAD OVER MOST OF THE WESTERN U. THE UPPER RIDGELINE WILL PASS EAST OF THE AREA LATE TONIGHT AND THEN SOUTHWEST FLOW AND WARM ADVECTION WILL BOOST TEMPERATURES ON SATURDAY BACK TO NEAR NORMAL FOR THIS TIME OF YEAR.
EXPECT THIS DRY AND COOLER AIR MASS TO STICK AROUND THROUGH SATURDAY AS HIGH PRESSURE SETTLES ACROSS THE REGION WITH THE COLDEST POST-FRONTAL TEMPERATURES EXPECTED ON SATURDAY MORNING. THIS WILL RESULT IN FREEZING/SUB-FREEZING TEMPERATURES IN MOST AREAS WITH A FEW OF OUR METRO LOCATIONS HOVERING JUST ABOVE THE FREEZING MARK.
421 AM CST FRI DEC 18 2015 COLDER AIR HAS SPREAD SOUTHWARD INTO CENTRAL ALABAMA THIS MORNING IN THE WAKE OF THE COLD FRONT THAT'S NOW ALMOST TO THE CAROLINA COASTLINE. WE'D BETTER ENJOY THE COOLER AND DRY WEATHER WHILE WE CAN OVER THE NEXT COUPLE OF DAYS. NORTHERN COUNTIES WILL STRUGGLE TO REACH 50 DEGREES WHILE SOUTHERN COUNTIES SHOULD TOP OUT IN THE MID TO UPPER 50S WITH THE MUCH COOLER AND DRIER AIR FILTERING SOUTHWARD.
THE SYSTEM'S COLD FRONT IS NOW MOVING THROUGH WESTERN WASHINGTON AND OREGON. THIS COLD FRONT WILL MOVE ACROSS THE REGION MID TO LATE MORNING TODAY. COLD POCKETS LINGER BELOW THESE LEVELS AND LIGHT FREEZING RAIN HAS BEEN OCCURRING. COLD AIR REMAINS OVER THE BASIN AND SOME LIGHT FREEZING RAIN OR SNOW WILL CONTINUE TO BE POSSIBLE THIS MORNING. THESE WINDS WILL GRADUALLY SETTLE AFTER THE COLD FRONT MOVES THROUGH. MUCH OF THIS PRECIP WILL BE SNOW AND OCCUR OVER THE HIGHER TERRAIN.
EARLY MORNING SATELLITE VAPOR IMAGERY SHOWED AN UPPER TROUGH AXIS OVER THE LOWER MISSISSIPPI VALLEY. UNDER CLEAR SKIES AND LIGHT NORTHWEST WINDS PREDAWN TEMPERATURES RANGED FROM THE LOWER 30S TO AROUND 40. THE UPPER TROUGH AXIS WILL MOVE EAST OF THE REGION FOR TONIGHT AS UPPER RIDGING BUILDS IN FROM THE WEST.
MID-LEVEL RIDGING OVER THE ERN GULF WILL SET UP A MODERATE SOUTHERLY FLOW ALONG THE WRN GULF COAST AND ALLOWING FOR A POSSIBLE RETURN OF A MID CLOUD DECK AS EARLY AS SATURDAY AFTERNOON.
546 AM CST FRI DEC 18 2015 FOR 12Z TAFS /ISSUED 322 AM CST FRI DEC 18 2015/ LATEST WATER VAPOR IMAGERY DEPICTS A WELL AMPLIFIED UPPER TROUGH EXTENDING THROUGH MUCH OF THE CENTRAL AND EASTERN CONUS. AND A RIDGE BUILDING IN OVER THE WEST. THE AXIS OF THE UPPER TROUGH WAS JUST TO THE WEST OF THE FORECAST AREA. ALLOWING TEMPERATURES TO DROP INTO THE LOWER 30S. FORECAST HIGHS WILL ONLY RISE INTO THE LOW TO MID 40S ACROSS MOST OF THE AREA. THE UPPER TROUGH WILL MOVE EAST OF THE AREA DURING THE DAY. AS THE RIDGE SHIFTS EAST. AS THE UPPER RIDGE SLIDES OVER THE SOUTHEAST.
WILL SEE READINGS TOP OUT IN THE MID TEENS THROUGH THE HIGHWAY 14 CORRIDOR TO MID 20S THROUGH THE LOWER MO RIVER VALLEY AND LOWER IOWA ZONES. UPPER LEVEL RIDGE AXIS SLIDES EAST ACROSS THE PLAINS ON SATURDAY. BREEZY SOUTHERLY WINDS INCREASE LATE MORNING AND AFTERNOON AND WILL ALLOW MUCH WARMER TEMPERATURES TO RETURN. WILL HOVER CLOSER TO FREEZING.
THE MAIN CHALLENGE FOR THE SHORT TERM IS TIMING FOR THE LOWER CLOUDS AND LIGHT SNOW/FLURRIES WILL MOVE OUT OF WESTERN AND CENTRAL NORTH DAKOTA. AN UPPER LEVEL RIDGE AXIS PUSHES EAST OUT OF THE ROCKIES AND INTO THE WESTERN PLAINS. WARM AIR ADVECTION CONTINUES INTO SATURDAY AS RIDGE AXIS PASSES OVER WHICH WILL BRING MILDER TEMPERATURES. SO WILL KEEP POPS ON THE LOWER SIDE.
718 AM EST FRI DEC 18 2015 SW WIND TODAY IN ADVANCE OF COLD FRONT WHICH WILL BRING SCATTERED SHOWERS AND PERHAPS ISOLATED THUNDERSTORMS TO THE REGION THIS AFTERNOON. A COLD FRONT CONTINUES TO MOVE INTO NORTHERN FLORIDA AND THEN FORECAST TO ENTER CENTRAL FLORIDA THIS EVENING. THE MODELS INDICATE HIGH PRESSURE BUILDING INTO THE SOUTHEAST STATES WITH A DRY AND STABLE AIR MASS BUILDING ACROSS SOUTH FLORIDA BEHIND THE FRONT. THE LOWS TONIGHT ARE FORECAST TO BE NEAR 50 TO LOWER 50'S ACROSS GLADES COUNTY. ON SATURDAY THE HIGHS ARE GENERALLY EXPECTED TO BE IN THE LOW TO MID 70S.
352 AM PST FRI DEC 18 2015 Cold frontal system moves into northern California today bringing much wetter pattern with rain and mountain snow across the whole north state by this evening. Satellite and radar imagery showing Pacific cold front just moving on to the north coast at this time and progged fairly well by short range models. main upper trough will be moving on to the coast by Saturday morning keeping precipitation going over most of the cwa through the morning hours.
LOOK FOR SKIES TO BECOME MOSTLY CLEAR AS HIGH PRESSURE SLIDES IN. LOOK FOR WINDS TO BECOME SOUTHERLY BY SATURDAY AFTERNOON AS LOW PRESSURE DEVELOPS OVER THE HIGHS PLAINS. HIGHS WILL RANGE FORM THE LOWER 20S ACROSS NORTHERN WISCONSIN TO AROUND 30 OVER NORTHEAST IOWA.
Upper level trough currently poised over our area, will continue to move east today. We will see a several degree rise in temperatures on Saturday as upper level heights rise as an upper level ridge begins building into the region. We should see highs well into the 40s to maybe close to 50 degrees out in SEMO, under a good amount of sunshine and light winds, as high pressure at the sfc stretches from the Gulf coast states up into the upper Midwest.
407 AM CST FRI DEC 18 2015 A COLD FRONT WILL CONTINUE TO PROGRESS SOUTHEASTWARD ACROSS THE MID SOUTH TODAY BRINGING A PERIOD OF CLOUD COVER THIS MORNING TO MUCH OF THE REGION. SKIES WILL CLEAR LATER TODAY AS CANADIAN HIGH PRESSURE BUILDS IN BEHIND THE FRONT. MUCH COOLER TEMPERATURES CAN BE EXPECTED TODAY WITH MOST LOCATIONS REMAINING IN THE 40S. AS THE HIGH SETTLES DIRECTLY OVER THE MID SOUTH TONIGHT. LOWS WILL RANGE FROM THE MID 20S EAST TO AROUND FREEZING IN DOWNTOWN MEMPHIS. THE HIGH PRESSURE SYSTEM WILL SLIDE EAST BY SATURDAY AND KEEP DRY WEATHER CONDITIONS IN PLACE THROUGH THE WEEKEND.
A RIDGE OF HIGH PRESSURE ALOFT WILL QUICKLY MOVE OVER NEW MEXICO TODAY.
623 AM EST FRI DEC 18 2015 AN UPPER LEVEL TROUGH WITH WEAK EMBEDDED DISTURBANCES WILL MOVE ACROSS THE GREAT LAKES AND OHIO VALLEY THROUGH TONIGHT. HIGH PRESSURE WILL BUILD INTO THE REGION ON SATURDAY.
950 AM EST FRI DEC 18 2015 THE COLD FRONT IS WITH THE LINE OF CONVECTION CURRENTLY IN PLACE ACROSS TAMPA BAY AND HILLSBOROUGH COUNTY.
536 AM EST FRI DEC 18 2015 COLDER CONDITIONS MORE TYPICAL OF DECEMBER WILL PERSIST TODAY INTO SATURDAY WITH HIGHS GENERALLY IN THE LOW 30S EACH DAY.
COLD FRONT THAT MOVED IN YESTERDAY AFTERNOON HAS ALREADY PUSHED WELL INTO THE WESTERN AND CENTRAL GULF OF MEXICO EARLY THIS MORNING. AN UPPER LEVEL TROUGH CAN BE SEEN ON SATELLITE TRAVERSING THE MISSISSIPPI AND OHIO RIVER VALLEY REGIONS. WITH A SURFACE COLD FRONT PUSHING SOUTH THROUGH TEXAS IN ITS WAKE. THE RIDGE WILL SCOOT EAST OF THE AREA LATER IN THE DAY. AN UPPER RIDGE WILL BUILD OVERHEAD TODAY AS THE TROUGH HEADS FOR THE EAST COAST. BUT TEMPERATURES WILL STILL HAVE A HARD TIME CLIMBING ABOVE THE 50S FOLLOWING LAST NIGHT/S COLD FRONT. RURAL LOCATIONS COULD REACH THE FREEZING MARK AGAIN BY SUNRISE SATURDAY.
Despite the cold start, temperatures will rebound nicely today under sunny skies, climbing into the middle to upper 50s for much of the area, with a few locations through the Rio Grande Valley and the Trans Pecos reaching into the lower 60s. Overnight low temperatures tonight will be closer to normal, ranging from the lower 20s to middle 30s across the area. Temperatures will continue to warm through the weekend thanks to weak upper ridging over the region, with highs Saturday in the upper 50s to around 70 degrees, and lows Saturday night roughly 10 to 12 degrees above normal in the lower 30s to upper 40s.
WARM AIR ADVECTION ALOFT AND AT THE SURFACE SHOULD ALLOW HIGHS TO REACH INTO THE LOWER 40S OVER THE WEST AND THE 30S FOR THE REST OF THE AREA. WARMER TEMPERATURES ARE EXPECTED FOR SATURDAY WITH INCREASING DOWNSLOPE FLOW. A SPLITTING WESTERN TROUGH WILL WORK ACROSS THE NORTHERN ROCKIES SATURDAY AFTERNOON AND NIGHT. THE TROUGH WILL BE SPLITTING AS IT WORKS ACROSS.
1011 AM EST FRI DEC 18 2015 ONLY MINOR ADJUSTMENTS MADE TO FORECAST TRENDS TODAY AS DRIER/COOLER AIRMASS CONTINUES TO ADVECT INTO THE CWA FROM THE NORTH USHERED BY SOME GUSTY GRADIENT WINDS. A DRIER COOLER AIRMASS IS MOVING IN BEHIND THE FRONTAL SYSTEM AND ALREADY SEEING SOME FREEZING TEMPS IN NW GA THIS MORNING. EXPECTING TEMPS THIS MORNING TO RANGE FROM THE LOWER 30S TO THE LOWER 50S AS THE COLDEST AIR HAS NOT MADE ITS WAY INTO THE STATE YET.
INCREASED CLOUD COVER HAS KEPT TEMPERATURES WARMER THAN YESTERDAY AT THIS TIME WITH MOST AREAS REPORTING READINGS IN THE 40S. AND WILL GRADUALLY INTENSIFY AS THE COLD FRONT APPROACHES. SHOWERS SHOULD MOSTLY END BY SATURDAY EVENING AS THE UPPER TROUGH MOVES TO THE EAST.
CANCELLED THE HIGH WIND WARNING FOR TELLER AND EL PASO COUNTIES BASED ON THE LATEST HIGH-RES GUIDANCE AND OBSERVATIONS. THE OTHER WINDY AREA IS THE HIGHER ELEVATIONS OF THE CENTRAL MOUNTAINS. HIGH PRESSURE OVER THE INTERMOUNTAIN WEST WILL SHIFT EASTWARD ACROSS COLORADO. DRY AIR WILL MOVE IN WITH THE UPPER LEVEL RIDGE WITH DRY CONDITIONS FORECAST THROUGH THE NEXT 24 HOURS. OVERNIGHT LOWS WILL BE WARMER ACROSS THE REGION. WHILE THE LOWER ARKANSAS VALLEY WILL LIKELY SEE TEENS.
BUT THE END RESULT WILL BE A SLIGHTLY COOLER AFTERNOON TODAY VS YESTERDAY DESPITE AMPLE SUNSHINE. A BRIEF PD OF FREEZING TEMPS IS POSSIBLE FOR INTERIOR LOCATIONS IN EAST TEXAS AND CENTRAL LOUISIANA EARLY SAT MORNING. RAIN CHANCES WILL ALSO BE ON THE INCREASE AS AN ACTIVE SOUTHWESTERLY JET IMPINGES ON THE REGION DOWNSTREAM OF BROAD TROFFING OVER THE WRN CONUS. 13 BRISK NORTH WINDS WILL CONTINUE THIS MORNING AS STRONG HIGH PRESSURE BUILDS INTO TEXAS. WINDS WILL DECREASE THIS AFTERNOON AS THE HIGH BEGINS TO SHIFT TO THE EAST. WITH A MODEST ONSHORE FLOW DEVELOPING LATE SATURDAY AS THE HIGH LIFTS NORTHEAST TOWARD THE MID ATLANTIC.
547 AM EST FRI DEC 18 2015 A COLD FRONT WILL SHIFT EAST OF THE FORECAST AREA EARLY THIS MORNING FOLLOWED BY DRYING. THE HIGH-RESOLUTION MODELS AND RADAR TRENDS SUPPORT SHOWERS MOVING OUT OF THE EASTERN MIDLANDS EARLY THIS MORNING. A DRY WEST FLOW BEHIND THE COLD FRONT WILL DOMINATE TODAY. WE WILL GET OFF TO A RELATIVELY WARM START AND THE WARMER TEMPERATURE GUIDANCE IS USUALLY BETTER WITH AN EARLY MORNING FRONTAL PASSAGE. THE DRY PRESSURE RIDGE APPROACHING SATURDAY SHOULD EXTEND THROUGH THE FORECAST AREA SATURDAY NIGHT. STRONG NET RADIATION COOLING WILL OCCUR SATURDAY NIGHT AND EXPECT FREEZING TEMPERATURES.
AS HIGH PRESSURE CONTINUES TO BUILD INTO THE REGION.
Low clouds over the Ohio and Tennessee Valleys will continue to move overhead during the morning hours as an upper trof comes in from the Plains. As the trof axis approaches, the upper parts of the cloud deck will edge into temperatures cold enough to support snowflake generation, so will continue with mention of flurries especially across southern Indiana and north central Kentucky. The trof axis will sweep through around mid day and will help to push clouds and flurries off to our east, resulting in at least partial sunshine this afternoon. High pressure crossing the southeast U. and ridging northward into the Great Lakes will give us mostly clear skies and light winds tonight and Saturday. Lows tonight will be in the 20s with highs Saturday mostly in the lower and middle 40s.
A COLD FRONT MOVING THROUGH THE REGION DURING THE MORNING WILL PRODUCE PERIODS OF RAIN WHICH MAY BE HEAVY AT TIMES EARLY IN THE MORNING THEN SHOWERS IN THE AFTERNOON IN THE WAKE OF THE FRONT. A COLD FRONT MOVING THROUGH THE REGION EARLY THIS MORNING WILL PRODUCE PERIODS OF MODERATE RAIN DURING THE MORNING.
Any severe weather threat should remain well south into Kansas, where an MCS is expected move through on the nose of the low level jet.
The weak upper level trough over the coast will continue to develop.
301 PM EDT Fri May 14 2021 Cyclonic flow has taken hold aloft as a trough moved into the eastern Gulf. Eventually strong surface ridging to the north will accelerate boundary layer easterlies. While moisture depth will decrease over time, the proximity of the low level boundary and moisture.
Freezing levels between 6500-8000 FT AGL is low enough that it shouldn't take a particularly tall updraft to produce at least small hail if not a few isolated reports of 1" hail before sunset.
330 PM EDT Fri May 14 2021 WV imagery and RAP analysis indicated wnw mid/upper level flow into the Upper Mississippi Valley upstream from a ridge through the central Great Lakes. There may be enough instability with CAPE values into the 100-300 J/Kg range for isolc/sct showers where the low level conv is strongest, mainly over the east with merging lake breeze boundaries.
214 PM EDT Fri May 14 2021 High pressure centers over the area tonight into Saturday morning and then moves offshore during the day on Saturday.
Current temperatures are in the low 70s and skies are mostly sunny.
Near term POPs were limited to slgt numbers over the higher elevations where weak troughing may support isold convection this aftn. Otherwise, broad high pressure will maintain dry weather through tonight while a warmer atmospheric column and insolation support temperature moderation close the seasonal avgs(71F at PIT). A weak, positively tilted, ern CONUS, to wrn Atlantic longwave trough with ridging ovr the WRN CONUS is projected to maintain varying degrees of nw flow ovr the Upr OH into Saturday night. Temperature in this time frame wl be near the calculated- normals as the overall atmospheric columns warms/trough fills.
Despite the high pressure and dry near-surface environment, steep lapse rates through the mid levels has resulted in a few showers this afternoon, especially across eastern upper Michigan. However, one big change will be with the low level thermal environment, with that much modified airmass keeping temperatures above freezing tonight. Far bigger story tonight will be the milder temperatures, with readings expected to remain at least a few degrees above freezing.
Temperatures remain 5-10 degrees below normal with temperatures in the low 70s for most. Tonight, the high will get pushed slightly to the southeast. Tomorrow, during the late morning hours, upper flow pushes high pressure to the east quicker. Pressure gradients, over the CWA, begin to tighten ahead of a low pressure system over the Plains. A frontal boundary develops from the low and east towards the our CWA. High temperatures reach into the low to mid 70s. In the upper levels, a split flow pattern is expected to develop across North America during the period with a cut off upper level low in the southwest US with mainly confluent flow downstream from the Mid-MS valley and points east.
The continued dry air in the low levels will fend off incoming precip associated with this wave, at least initially.
1035 AM CDT Fri May 14 2021 (Issued 1035 AM CDT Fri May 14 2021) The winds are gradually starting to shift southerly late this morning as the high pressure begins to depart. Patterson (Issued 300 AM CDT Fri May 14 2021) Today through Saturday: The influence of gradually departing high pressure will prevail today.
It has been very dry in the low levels so rainfall amounts were on the light side where it did reach the ground.
Tomorrow is expected to be warmer, and chances for showers/storms continue - mainly across northern and southwest Oklahoma into western north TX.
AC Chattanooga Airport, TN 50 77 57 81 59 / 0 0 0 10 10 Knoxville McGhee Tyson Airport, TN 46 74 55 76 57 / 0 0 10 20 20 Oak Ridge, TN 47 74 54 75 56 / 0 0 10 30 20 Tri Cities Airport, TN 43 71 51 69 54 / 0 10 20 40 30.
Very dry air in the low levels per regional observed soundings and RAP guidance has been limiting how much rain can make it to the surface, but indeed some stations just upstream have been reporting light rain at times - surprising, considering the nearly 30 degree dewpoint depression in place. Forecast soundings start to moisten up in the low levels this evening as mixing diminishes, which will lend itself to a greater chance of steadier rainfall getting down to the surface tonight.
Northwesterly flow aloft prevailed over the area with an upper low over the Mid Atlantic region while broad ridging was evident over much of the Four Corners states. Toward the surface, high pressure extended from the Mid Mississippi River Valley northeast into the Ohio River Valley. Upper-level ridging will move east over the Central Plains while the closed low to our northeast lingers near the Mid Atlantic coast. Expect mostly clear skies tonight with lows ranging from the mid 40s north to the low 50s far southeast. A few of the typically cooler spots north and northeast may experience lows in the lower 40s. Look for partly cloudy skies across the area Saturday with highs ranging from the upper 70s north and east to the low 80s south and west.
The short wave will continue to dig, forming a closed low over northern California tonight into Saturday. Flow aloft will become northeasterly as a ridge flops over the top of the low, but short waves rotating around the low will continue to enhance instability.
Lows tonight mainly in the low to mid 50s inland, with upper 50s to low 60s along the coast.
A larger more significant upper low will be moving into Central California at the end of the short-term. It will feel a bit warmer as dew points inch upwards into the 70s with winds becoming southeast at moderate speeds tomorrow.