Aikyam-Lab/Synoptic-Bench huggingface dataset:
Satellite shows some mid and upper-level clouds along with smoke aloft expanding across the forecast area from the southwest as an upper trough approaches. Tomorrow, first in a series of upper level troughs will move across the forecast area. Moisture will be fairly limited ahead of this trough, with just enough for mid to upper level cloud decks to stream from north to south across the region. Overnight radiative cooling will likely be inhibited in those areas under the cloud cover, leading to tomorrow morning's lows 7-10 degrees warmer than this morning. Upper level trough coupled with cold front passage tomorrow afternoon will bring increasing westerly winds through the Cascade gaps, but conditions will continue to be mostly dry with no showers expected across the forecast area.
343 AM CDT Wed Aug 25 2021 Upper ridging will continue to control our weather locally, meaning another hot and dry day. Temperatures should be very similar to yesterday, peaking in the middle 90s for most spots on the Caprock, while the lower elevations to the east reach the upper 90s to about 104 degrees.
Overnight lows will only drop into the lower to middle 70s. Scattered convection will once again develop on Thursday as central Illinois remains on the northern periphery of an upper level ridge of high pressure centered over the Southern Plains into the Lower Mississippi River Valley. As a significant short- wave trough crosses the Rockies, the downstream ridge will build northward by the end of the week.
344 AM CDT Wed Aug 25 2021 H5 analysis from earlier tonight had an elongated area of high pressure extending from New Mexico east into the Tennessee valley. High pressure was anchored over Bermuda. Across the western CONUS, a trough of low pressure extended down the west coast of the United States from Washington to northern California. Weak northerly and northeasterly winds will bring in cooler air to the forecast area.
Otherwise, an upper low near the Bahamas will continue to move NW into FL, pushing weak upper troughiness and band of enhanced moisture, with PW over 2 in, that's currently just offshore the Carolinas, into our FA. Overall severe potential appears low with weak to moderate instability, lack of dry mid level air, shallow low level inverted V and high freezing level/WBZ heights. High pressure will be ridging across the forecast area Thursday with a moisture gradient just south of the area. With mid and upper level ridging also over the area models show a subsidence inversion which will limit convection.
Today Through Thursday Night An upper ridge continues over the central and southern U. with an upper trough over the west coast. The center of the ridge is over Oklahoma and will move east Thursday. Highs will be in the mid and upper 90s today and a bit cooler on Thursday. Lows at night will be in the lower to mid 70s.
People generally think urban areas will see the higher heat indices. Dewpoints are expected to reach the low to mid 70s.
/NEW/ /Through Thursday/ A mid/upper ridge will remain entrenched across the Southern Plains today, with 595 decameter heights at 500 mb expected over much of the region. This will keep the typical August heat in place for at least another day, with afternoon high temperatures ranging from the mid 90s to the lower 100s. The ridge will retreat north some on Thursday as a broad inverted trough moves westward through the Gulf and eventually into South Central Texas. The subtle weakening of the ridge should knock a couple of degrees off Thursday high temperatures.
246 AM CDT Wed Aug 25 2021 After some morning isolated convection, ridging will allow for the hot and dry conditions to continue through the short term.
354 AM CDT Wed Aug 25 2021 The dome of high pressure remained firmly in place across the Southern and Central Plains early this morning.
The thunderstorm complex will likely continue into northern MO during the remainder of the overnight, but the low level jet should weaken by 12z and the convection should begin to die out early Wednesday morning. It will remain quite mild with lows in the low to mid 70s.
1235 AM EDT Wed Aug 25 2021 A weak mid and upper level trough along the Southeast coast will drift slowly westward and inland over the Carolinas and Southeast states through Thursday, as it weakens further and dissipates.
A subtropical ridge remains in place to start the period across much of the eastern CONUS. This persistent ridging pattern will continue to offer temperatures well above climatological normals for this time of year. The ridging pattern becomes more amplified over the weekend, lifting further north into the Great Lakes region.
Elongated west to east mid level ridge Oklahoma to mid Atlantic states with confluent 40-50kt mid level flow across Upper Midwest into northern Great Lakes.
Latest regional radar analysis shows a cluster of thunderstorms, associated with a crossing weak trough, pushing east across north central Ohio.
949 PM MDT Tue Aug 24 2021 A weak cold front is located up against the east side of the Continental Divide with cooler temperatures today especially over the Bighorn Basin and Johnson County. The forecast area will be between a ridge to the east and an approaching trough from the west, just moving into Idaho.
Isolated thunderstorms this afternoon, mainly across the higher elevations. Discussion: Upper ridging continues to be the main factor in our weather today with a mostly clear sky and above normal temperatures.
Temperatures are hovering in the lower to mid 80s, and winds on land are from the northeast to east around 10 mph. Surface analysis depicts high pressure centered over the central Atlantic and extending westward to north Florida, while a low pressure trough is located over the eastern Bahamas. This trough is moving westward in tandem with a large mid/upper level trough which is centered over the Bahamas. Ahead of these troughs, a dry airmass remains in place over the Keys due to the Saharan Air Layer (SAL) passing westward through our region. The trough axes at the surface and aloft will move westward through our area tonight, with PWs forecast to peak near 2 inches. Thursday should see a return to near normal rain chances, as the trough continues moving westward into the Gulf.
920 PM PDT Tue Aug 24 2021 High pressure building into Southern California from the east will allow for temperatures to climb through the end of the work week and a shallow marine layer with less night and morning low clouds and fog. High pressure currently centered over the Great Plains will continue to build westward suppressing the height and influence of the marine layer, with only patchy coverage of night and morning low clouds and fog expected tonight and over the next several days. The increasing strength of the high pressure will allow for temperatures to climb 4 to 10 degrees above normal for all inland areas.
Little change forthcoming tonight and Wednesday as a mid-level trough remains to the west of the forecast area. Expect highs on Wednesday to be just a bit warmer than normal. Quick burst of monsoonal moisture will be working through Thursday as an upper level trough over the Northern Rockies fills and ejects northeastward into Southern Canada.
1014 PM CDT Tue Aug 24 2021 Cold front currently extends from around LOW into west-central MN trekking eastward.
Afternoon showers and thunderstorms are expected across the higher elevations, but any impacts within the vicinity of terminals is too low to include at this time. Winds remain light and variable with high pressure across the region. JB Chattanooga Airport, TN 93 72 88 70 88 / 20 10 50 10 30 Knoxville McGhee Tyson Airport, TN 94 71 90 70 90 / 30 10 50 10 20 Oak Ridge, TN 93 71 89 69 89 / 20 10 50 10 20 Tri Cities Airport, TN 92 68 89 66 90 / 30 10 50 10 20.
100 AM EDT Wed Aug 25 2021 High pressure will continue offshore with weak troughing over inland areas through Thursday.
Wednesday will also be hot, but the lack of downslope will keep us just a bit cooler. Upper level ridging will remain over the plains through Thursday and then slowly move off to the east by the weekend.
The upper ridge over the southeast will weaken and move northward as an inverted upper level trough approaches from the east. With the increasingly moist mid and upper levels and approaching mid- level trough, scattered to numerous showers and thunderstorms can be expected by Wednesday afternoon. Storms may linger into the late evening on Wednesday due to the presence of the approaching trough. The inverted trough weakens as it moves across the area on Thursday with the higher rain chances over mainly western areas as the ridge rebuilds slightly.
Upper ridging over the area will begin to break down Thursday allowing afternoon temperatures to slowing decrease in the coming days. Subsidence under the ridge will keep the entire area dry through at least the short term.
High temperatures today will climb into the middle 90s, and with dew points in the lower to middle 70s, heat indices will climb into the 103 to 108 degree range. Some models are showing a weak ripple in the upper trof over our region Thursday producing some scattered QPF, and this signal has been fairly consistent.
Expect this activity to slowly drift southward through the morning, gradually diminishing as the low- level jet weakens. Most of the area will end up at least a few degrees cooler than yesterday. By Thursday, the warm front should have lifted northward across the area, and high temperatures will return to the 90s across Nebraska to the low 100s across northern Kansas. Again, the daytime should be primarily dry, but a deeper upper trough approaching the area should force scattered thunderstorm development along a cold front over the Sandhills by late afternoon.
Temperatures will continue to remain in the low to mid 90s with heat index values in the 100-108 degree range the next couple afternoon. It is in his area where additional cloud cover will hold temperatures in the lower 90s. Tonight the axis of the upper level ridge, which has brought us the hot weather, will move directly over the CWA. As such temperatures across the northern CWA are again expected to remain in the lower 90s where the rest of the CWA will again reach mid 90s.
1107 PM CDT Tue Aug 24 2021 (This evening through Wednesday) Dewpoints are currently in the low 70s from central OK eastward along with low to mid 90 temps resulting in triple digit heat index values. Similar and even warmer conditions are expected by tomorrow afternoon under the upper high.
A broad upper ridge remains parked across the southern half of the central U. The hottest day is still shaping up to be tomorrow (Wednesday) as the 500mb ridge axis sets up right along the KS/MO border.
1100 PM CDT Tue Aug 24 2021 After this morning's convection temperatures have been cooler than originally forecast thanks to evaporative cooling, cloud cover, and a well mixed boundary layer. These cooler temperatures will lead to diminished instability and less chance for convection across much of central and southern Minnesota as well as west central Wisconsin later today. Behind the passage of a cold front Wednesday should be a much quieter day of weather. Cooler air and a shift to northwest winds will be the story for Wednesday.
1232 AM CDT Wed Aug 25 2021 High pressure continues over the area. Tonight Through Thursday Strong high pressure will remain over Arkansas through Wednesday causing the intense heat of late to continue with Heat Advisories, if not Excessive Heat Warnings, once again expected for the entire area Wednesday afternoon. In the Wednesday night/Thursday timeframe, the strong high pressure will get shunted northward somewhat in response to a subtropical low pressure system moving into the eastern Gulf of Mexico from the western Atlantic. The northward movement of the high pressure will help shave one to three degrees off of daytime highs Thursday afternoon, but it is anticipated that Heat Advisories will continue area-wide for one more day as humid conditions persist.
A deep upper trough will be moving into the northwestern CONUS through the day, which will set up southwesterly flow aloft across the northern Plains.
Confidence is low on this because of the strong ridge in place,fairly dry, mixed, soundings, meager lapse rates locally and weak shear. The upper-level ridge is forecast to weaken some Wednesday night and Thursday in response to a trough passing through Ontario. Closer to home, this sends a weak front (850 mb cold front) through the area. With the ridge axis now over the eastern-third over the CONUS, we find ourselves on the western edge under improved moisture from the Gulf.
1247 AM CDT Wed Aug 25 2021 A forecast update is in place for isolated showers and thunderstorms forming along a cold front moving through the srn Sandhills.
Another warm day is expected for northeast Montana on Thursday as the upper ridge axis slides east ahead of an approaching cold front.
Meanwhile, robust mid level ridging extends across the Southern Rockies into the Southern Plains and Gulf Coast. For tomorrow, as the low lifts northward across the southern and central Florida peninsula, even more widespread shower and thunderstorm activity is expected. The combination of deep tropical moisture with the usual afternoon seabreezes and weak lift associated with low pressure should yield widespread rainfall coverage.
250 PM MDT Wed Aug 23 2017 With an upper level ridge moving east tonight and a weak upper level trof approaching the region, a few isolated thunderstorms will be possible over Southwest MT.
226 PM EDT Wed Aug 23 2017 An approaching cold front will cross the area tonight into Thursday. High pressure will build into the region for the end of the week. bringing a cooler and drier airmass. High resolution models keep a majority of the activity near the Pee Dee region, so have kept the highest POPS there. Overnight low temperatures in the lower to middle 70s. Thursday morning, the cold front will be over the eastern Midlands with dry air pushing from the west.
The cold front is now to the east of the terminals with drier air advecting in from the northwest.
The cold front is now to the east of the Appalachian Mountains with drier air advecting in from the northwest. There were a few showers earlier this morning across the higher elevations but not seeing much in the way of radar returns currently. for the higher elevations over the next couple of hours with dry conditions forecast afterward. Low temperatures will be cooler than normal ranging from the mid 50s to mid 60s. At the beginning of this forecast period, we are on the southern end of an upper level NW flow, while at the surface, in the wake of the cold front, high pressure and north winds continue to build into the area, resulting in dry weather.
131 PM CDT Wed Aug 23 2017 Yesterday's cold front has moved far to our south as high pressure builds in from the northwest. Considerably cooler, drier air has replaced the previous heat and humidity. Owing to a lack of any appreciable return flow the next 7+ days, the cooler air is here to stay for while.
215 PM EDT Wed Aug 23 2017 Cooler and drier under high pressure into the weekend. Back into a fog pattern with high pressure building and cool and dry air continuing to filter in after a cold frontal passage. Models in good agreement with high pressure in control, with warm sunny days and cool foggy nights/mornings.
152 PM EDT Wed Aug 23 2017 Cooler and drier under high pressure into the weekend. Back into a fog pattern with high pressure building and cool and dry air continuing to filter in after a cold frontal passage. Upper trough over the eastern third of the nation will bring much cooler and drier air southward from a large high pressure system centered over central Canada. Overall, it will be nice weather, with the much cooler and less humid conditions.
312 PM CDT Wed Aug 23 2017 Cold front continues to make its way swd this aftn, and is now s of I-20.
Ridging begins to push eastward this evening as a low pressure system moves into central Canada. Associated weak cold front will slide into the area tomorrow night. Ahead of the cold front, scattered thunderstorms will develop in the mountains during the afternoon and transition eastward onto the Plains during the late afternoon and early evening.
537 PM CDT Wed Aug 23 2017 Other than temperatures running a little warmer than forecast for portions of northern and western ND, the forecast is on track with no other changes made. Current surface analysis places high pressure stretching from the midwest into the central plains while low remains to the lee of the Rockies. Upper level analysis places ridge stretching from the central Rockies into the western Canadian plains with northwest flow over our area. On Thursday, besides some clouds passing through eastern locations, a mainly quiet day is on tap as upper ridge axis passes over. Behind the ridge axis, potent short wave attempts to close off as it slides into the plains.
353 PM EDT Wed Aug 23 2017 A cold front will move into the area tonight and linger nearby through the end of the week.
436 PM EDT Wed Aug 23 2017 Cooler and drier under high pressure into the weekend. Removed any mention of showers from the forecast this afternoon and evening as much drier air aloft pushes in with high pressure. Back into a fog pattern with high pressure building and cool and dry air continuing to filter in after a cold frontal passage. Models in good agreement with high pressure in control, with warm sunny days and cool foggy nights/mornings.
This morning our region is on the far northern extent of a weakening ridge across the NE Gulf that extends eastward across the Florida Peninsula.
308 PM CDT Wed Aug 23 2017 Current surface analysis places high pressure stretching from the midwest into the central plains while low remains to the lee of the Rockies. Upper level analysis places ridge stretching from the central Rockies into the western Canadian plains with northwest flow over our area. On Thursday, besides some clouds passing through eastern locations, a mainly quiet day is on tap as upper ridge axis passes over. Behind the ridge axis, potent short wave attempts to close off as it slides into the plains.
308 PM CDT Wed Aug 23 2017 A ridge is situated over the western CONUS while a trough hangs over roughly the eastern half. Kansas remains in the ridge territory which has prompted fabulous conditions for the day with clear blue skies, temperatures in the 80s and light winds by Kansas standards. A trough is traveling down the coast of British Columbia and soon heading east to the Rockies. There will be troffing along the lee of the Rockies prompting potential thunderstorm development in the northern portions of the High Plains.
118 PM EDT Wed Aug 23 2017 An approaching cold front will cross the area tonight into Thursday. High pressure will build into the region for the end of the week. bringing a cooler and drier airmass. A broad upper trough will slowly move through the eastern states today and tonight. pushing a cold front into the area tonight. Expect afternoon temperatures to warm to the mid 90s with overnight lows in the low to mid 70s. The cold front is forecast to be over the eastern Midlands Thursday morning. Weak waves of low pressure developing along the front will slow its movement.
Modest northwest flow aloft is in place aloft with some bits of cirrus attempting to work their way into the central Plains downstream of an upper low off the California coast.
313 PM CDT Wed Aug 23 2017 H5 analysis this morning had closed low pressure over Quebec with a trough of low pressure extending south into the central Appalachian Mountains. High pressure was south of the trough over the western Atlantic, off the coast of northern Florida. High pressure extended west to northern Mexico, where a secondary high pressure was located south of Arizona. A ridge extended north of this feature into the northern Rockies and into northern Alberta. At the surface, high pressure was located over southeastern Nebraska near Falls City. Further west, a more favorable set up for convective development appears along the Cheyenne ridge of se Wyoming and am expecting convective development there. As this activity moves east it is expected to dissipate as the low level jet is anchored well east of the panhandle.
1119 AM MDT Wed Aug 23 2017 Another round of thunderstorms expected today with residual moisture and weak embedded disturbances still circulating within the upper ridge over CO. Thunderstorms will linger into the night across the plains as the surface trof axis shifts eastward and low level jet cranks up. Active weather pattern looks to continue with a weak disturbance translating through the weak westerly flow aloft, as upper high pressure starts to build back into the Desert Southwest. Minor wave should help develop storms across the higher terrain through the late morning and afternoon, with storms moving across the adjacent plains through the late afternoon and evening.
1251 PM CDT Wed Aug 23 2017 Quiet, cooler, and drier weather continues today. Subjective 00Z upper-air analysis indicates a deepening upper-level trough in the eastern US and ridging in the west, with northwesterly flow across the central US. Frontal passage had brought much drier and slightly cooler mid-level air to the central US, with 12C+ dewpoints at 850mb confined to the southern Plains to TN River valley area and southward. A pocket of cooler 850mb temperatures was noted in ON, but in the central Plains, temps were still 10-20C from east to west.
212 PM EDT Wed Aug 23 2017 Primarily fair weather will continue through the weekend as high pressure dominates the region. dry Canadian airmass will continue to build into the region as lows tonight will drop down into the lower 50s while added cloud cover will limit highs to upper 60s to around 70 in NW CWA and lower 70s elsewhere on Thursday.
Moisture will be slow to return as we eventually as we continue our transition to northwest flow aloft, while an amplifying upper ridge develops over the Rockies.
Unfortunately, one of the lowest confidence areas will be between KOKC and KOUN, where KOUN will have a higher probability of restrictions relative to KOKC, by the edge of low clouds/fog will be spatially close.
The first area is over Mono-Alpine counties and southern portions of Douglas-Lyon-Mineral counties, in association with deformation zone north of the upper low centered near the southern CA coast.
Steep low-level lapse rates will support modest instability sufficient to generate a cu field by early afternoon, but the lowering inversion height will limit vertical depth and any chances for precipitation. A broad upper trough in the ern CONUS will dominate the wx pattern through much of the remaining forecast as an upper ridge amplifies in the central CONUS.
In fact, valley dew point values across the forecast area were in the mid- 40s with the exception of KGJT which recorded dew points in the low 50s early this morning. First, a possible tropical depression or storm will be just about coming ashore over Texas while a weak area of low pressure will continue to spin over SoCal. This low has been in the same general area for several days now but finally looks to start filling in by the weekend. Finally, a trough and associated front will be moving over British Columbia to our northwest.
300 PM MDT Wed Aug 23 2017 Current surface analysis shows frontal boundary stretching from central MT through eastern WY to weak low pressure over far southeast WY. Upper level analysis shows negatively tilted ridge centered over the northern Rockies, with northwest flow continuing across the Northern Plains. Will see southeasterly winds increase on Thursday, becoming breezy across the SD plains, as low pressure forms along the boundary over eastern MT.
However, cu cigs have developed over Deep E TX and much of N LA, near a weak mid level trough extending from SE TX into Ncntrl LA. /issued 1133 AM CDT Wed Aug 23 2017/ Cold front now located roughly along I-20 and movg swd this morning.