Aikyam-Lab/Synoptic-Bench huggingface dataset:
351 AM CST Mon Nov 20 2017 09Z/3 am surface map shows 1025 mb high pressure over the TN river valley and ridging into the southeast Ohio river valley. 991 mb low pressure was over southern Saskatchewan. High pressure to drift over the Carolinas this afternoon while low pressure moves ESE into southwest Ontario by sunset and continues to increase pressure gradient over area today. Highs in the lower 50s over east central CWA and upper 50s to around 60F from Springfield sw. Low pressure deepens to 987 mb as it tracks eastward across central Ontario province during tonight, pulling a cold front se toward the IA/IL border by 12Z/6 am Tue.
1235 AM EST Mon Nov 20 2017 High pressure and dry conditions will build into the region through Monday.
142 AM EST Mon Nov 20 2017 Dry and cool high pressure will build across the area through Monday.
422 AM EST Mon Nov 20 2017 Dry and cool high pressure will build across the area today.
Dry high pressure will settle over the region with calm winds overnight, becoming light south on Monday.
Synoptic Setup: Forecast begins with an exiting meso-ridge over the High Plains of Montana and southern Alberta and the Dakotas. farther upstream, another pacific ridge-trough couplet sets off the coast of British Columbia. Meanwhile, off the coast of California a surge of warm air is forming into a synoptic ridge. as the cold front moves through the CWA during the afternoon temperatures will begin to fall and Winds will become gusty.
305 AM EST Mon Nov 20 2017 High pressure centered near Nashville this morning will advance to the Carolina coast by this evening and then off the coast tonight. Tonight most spots should remain just above freezing with the exception of the usual sheltered cool spots.
215 AM EST Mon Nov 20 2017 High pressure will build overhead late tonight and Monday.
350 AM CST Mon Nov 20 2017 Early morning sfc analysis shows high pressure centered over the lower Mississippi Valley, ridging swwd across the forecast area with a light nerly low-level flow in place helping maintain our recent cool conditions with observations showing temps ranging from near freezing nern zones to lower 40s srn zones.
Ridging will build north out of Baja California into the Intermountain West and the Canadian Rockies thru the first half of the week.
The resulting continental polar airmass intrusions will keep temperatures cooler and dry conditions in place. After sunrise, temperatures should gradually rebound into the low to mid 50s today underneath a sunny to mostly sunny sky. The high pressure system should move east today causing weak northerly winds (around 5 MPH) to veer to the southeast.
Flow pattern through the mid and upper levels is from the northwest, with more of a northerly pull the upper high you go towards jet level.
Northeast winds from this high will mean continued cold air advection. Tonight then looks very chilly across the region as that high pressure settles into the Ohio Valley region. Areas back west towards the I-49 corridor will be slightly warmer (lower to middle teens) as winds turn around to the southeast and increase a bit.
High pressure aloft along the west coast will maintain a dry and mild west-northwest across much of Utah over the next several days. The mean ridge position currently just off the west coast will maintain a downstream west-northwest flow across the Great Basin over the next several days. Leaning the forecast at the end of the week toward the ECMWF solution which nudges the west coast ridge a bit further east than the latest GFS solution.
Upper air analysis last evening showed a broad trough across the country with westerly flow over Texas. At the surface, a stationary front was stretched from Deep South Texas along the Rio Grande to a low near Del Rio and then a cold front extended into Mexico. The low level flow will continue northeasterly today and then turn to the east tonight and Thursday. Thursday is looking dry with high pressure moving across north Texas.
A chilly air mass remains in place today with dry advection in the lower levels of the atmosphere. Cold high pressure slips further east to cover much of the eastern half of the nation.
Temperatures will rebound to above freezing and nearing the lower teens. The lake effect flow regime continues today as westerly winds shift to the northwest as a high pressure around 1045 mb will drift across Wisconsin and the western Great Lakes throughout this afternoon. As the high pressure drifts further through the region, that will help cut winds down enough tonight to where wind chills do not reach advisory criteria like the last couple nights.
A ridge will slide through the area tonight, which will bring an end to the lake effect snow over most or all of Upper Michigan. In fact, there may be a narrow but possibly intense area of snow into Alger and northern Schoolcraft counties until 12Z Thu as shown by some of the high-res models. Broad troughing remains over the area this forecast period along with the cold air and lake effect snow. In the extended, GFS and ECMWF show a broad 500 mb trough over the central U. No gales are expected, but could see a few gale force gusts later this week through the first half of the weekend, along with periods of heavy freezing spray. Heavy Freezing Spray Warning until 7 AM EST this morning for LSZ249>251-266-267.
Aloft, flow across the central CONUS remains northwesterly, set up between broad ridging/troughing over the west/east coasts. At the surface, high pressure is centered over the eastern half of NE, resulting in light/variable to calm winds across the CWA. while under the cloud cover they are a bit "warmer", in the single digits above zero. At the surface, the area of high pressure will continue to slide east today, resulting in more southerly winds across the CWA. For Thursday, it remains the "warmest" day of the entire forecast period, with highs in the lower 20s to near 30 possible.
Have also kept forecast cloud amounts on the lower end again tonight and early Wednesday. The arctic air returns after the low passes with temperatures falling back into the teens and twenties below zero for the weekend.
312 AM EST Wed Dec 27 2017 Strong high pressure will be centered northwest and north of the forecast area through Thursday night. The high will direct cold air into the region. An area of low pressure along the front will bring light rain to much of the area this morning. Another low may bring light precipitation to the southeast section of the forecast area Thursday and Thursday night with freezing rain possible Thursday night.
210 AM MST Wed Dec 27 2017 High pressure will continue to sit over the region this week with only periods of high clouds spilling into the area. With a dry airmass locked in place, seasonable morning temperatures will be followed by afternoon highs warmer than average into the 70s. However, building ridging/heights along the California coast will act to suppress the flow of moisture poleward while also increasing deeper subsidence into the forecast area this afternoon. Thus, better sfc insolation and deeper mixing depths should be more common and yield afternoon highs several degrees warmer than the past several days. The 584dm core of a H5 high pressure system (above the 90th percentile seasonally) will eventually settle over SE California/SW Arizona later this week yielding temperatures some 10F above average (but probably just short of record territory).
A this point, hedged cooler over snow covered areas in Central KS and a bit warmer across the south.
219 AM EST Wed Dec 27 2017 Strong high pressure will be centered northwest and north of the forecast area through Thursday night. The high will direct cold air into the area. A series of low pressure centers will track along the front.
Strong 1045 mb arctic high pressure over eastern Nebraska and nw MO will settle east over central and eastern IL by early this evening. Arctic high pressure settles east of IL over the southern Great Lakes and upper ohio river valley by dawn Thu.
Clouds are expected to increase from the west to east Wednesday morning as the 850mb ridge shifts to the east and we start seeing return flow. Increasing clouds will keep high temperatures on Wednesday in the low to mid teens. Temperatures on Thursday have nudged up a bit more, but should still stay below freezing for most of the forecast area.
/issued 941 PM CST Tue Dec 26 2017/ Advisory for freezing drizzle was cancelled as much drier air has spread well south of the Red River.
We still see a slight opportunity for isolated flurries overnight as weak isentropic lift in the 275k layer combines with a slight increase of low level moisture, especially given the lower level of the DGZ. A cold front will move in Wednesday night, and limit any warmup for Thursday.
Moisture in the lower levels appears to be in limited supply through the forecast period.
Cold high pressure remained across much of the region at 20z, extending from western Canada into the central plains. Most of the forecast area will experience some of the coldest temperatures so far this season tonight as the high sinks slowly southeast. Temperatures will moderate briefly on Thursday into the upper teens and 20s before the next cold front moves through the region during the day.
Very cold temperatures bottomed out overnight generally from the low to mid teens below zero across the region.
337 AM CST Wed Dec 27 2017 Coldest temperatures of the season are close to, if not at record territory this morning as a 1044mb high pressure ridge axis slides directly overhead.
Patchy fog is expected again along portions of the coast tonight, however the high clouds may limit develop. Latest runs of the high resolution models are backing off on low cloud development this evening, with better cloud and fog coverage late tonight.
Slow improvement is possible Wednesday afternoon through Wednesday evening from north to south, but think the lower levels could linger longer from IAH southward. /ISSUED 346 PM CST Tue Dec 26 2017/ Low amplitude trough and associated ascent continues to shift away from east TX this afternoon, pulling weak showers with it. This will also aid in shifting reinforcing cold front now moving into central TX offshore tonight. Overall should see a trend towards somewhat warmer weather into late week/early weekend before yet another cold front ushers in return to much below normal temps to start the New Year. Winds will veer to more of an easterly direction later in the week as high pressure moves away.
Overall not a strong low though some isentropic lift for the first part of the snowfall then energy from mid level wave and lower level troughing.
Snow shower chances thus continue for areas north of I 80 corridor and the ridges of WV and MD, but no problems are anticipated given limited mixing heights and ambient dry advection.
Wind Chills: High pressure will begin to nudge into the region; therefore, expect skies to remain mostly clear with dry conditions across the interior west and central. Broad troughing remains over the area this forecast period along with the cold air and lake effect snow. In the extended, GFS and ECMWF show a broad 500 mb trough over the central U. Heavy freezing spray will also linger across much of the lake into Wednesday morning.
241 AM CST Wed Dec 27 2017 Cold air advection continues across Middle Tennessee this morning in the wake of a cold front that moved through yesterday. High temperatures are not expected to even reach the freezing mark for most of the cwa this afternoon, with temperatures plummeting into the teens areawide Wednesday night - the coldest night across Middle Tennessee since January 8, nearly one year ago.
Snow shower chances thus continue for areas north of I 80 corridor and the ridges of WV and MD for the morning, but no problems are anticipated given limited mixing heights and ambient dry advection.
Surface analysis shows arctic high pressure over the upper midwest spilling southeast into the Ohio Valley. Broad upper troughing expected across the Great Lakes and Ohio Valley during this period. Models suggest a weak short wave trough may move through the Great Lakes Thursday and Thursday night.
Strong Arctic high pressure ridge will build into the area progressively over the next 12 to 24 hrs and will help overnight temperatures plummet to well below zero especially north of I-70. Expansive high pressure slides east into the Great Lakes and Ohio Valley region by Thursday.
Arctic high pressure, sitting over the Northern Plains, will continue an eastward scoot through the morning centering over Iowa around 18Z. As the high progresses east, a surface warm front will push northeastward into the region. "Warmer" air will filter into the state, helping temperatures in southern and central areas climb above zero. The high temperature forecast ranges from the single digits above in the south, to the single digits below zero north. Still well below average though a little warmer than past days. Chances for snow will also accompany the warm front.
VFR cigs will be returning as cold and dry air continues to deepen in the lower levels.
The high will then exit throughout the day with minor return flow starting and nudging temps into the single digits above zero and then staying fairly steady overnight with clouds and southerly winds.
1235 AM EST Wed Dec 27 2017 Bumped up temperatures a bit across the area with temperatures running a few degrees warmer than current forecast, and this will lead to a slightly sharper temperature gradient from north to south tonight. High pressure is centered across the northern Plains, with very cold air gradually building southeast into the lower Ohio Valley. Another mostly cloudy day has been on tap for eastern Kentucky, with temperatures ranging from the low to mid 30s across the area. Some of the higher resolution models suggest a glancing blow of measurable snowfall north of I-64, but given the dry low levels and weakening trend to the mid-level short wave, will keep POPs low. A gradient of warmer readings will be found towards the Tennessee/Virginia border, where lower 20s will be more common.
Forecast for tonight still on track as high pressure builds into Illinois. Broad troughing over North America is expected to be in place at least through the workweek. Rapidly moving weak disturbances plunging southeast into the trough base will impact our weather through that period with shots at snow followed by reinforcing shots of arctic air. Northwest winds will trend more toward the east/northeast by late afternoon, as high pressure passes to the north.
Cold front currently making its way southward through the mid state. Moving on, on Thursday a weak inverted trough will traverse the mid and deep south. We will see slightly warmer temps with the mercury reaching the upper 30s to lower 40s.
1033 PM CST Tue Dec 26 2017 Cold high pressure will drift across the area tonight, allowing for another very cold night/morning. As a relatively weak wave moves into the Central Plains on Wednesday the west and southwest flow in the low to mid levels will increase.
146 AM PST Wed Dec 27 2017 A persistent ridge of high pressure along the west coast will provide a quiet and dry end to the year with above average daytime temperatures, areas of high clouds, and light valley winds. There is potential for cooler temperatures and wetter storm systems moving through the region during the first week of January.
1122 PM CST Tue Dec 26 2017 Tonight: This afternoon, a deep upper-deck low continued to cover Ontario but was weakening while upper-deck ridging was punching NNW from just off the Pacific Northwest Coast to the Gulf Of Alaska. The GFS takes a MUCH STRONGER & FASTER approach on the SE track of the Arctic High, bringing it as far south as the Nebraska/Kansas state line late New Year's Eve night & early New Year's Day morning whereas the ECMWF brings it only as far as the Dakotas/MN with the attendant inverted ridge reaching as far as around the IA/MO state line.
Moisture and warmer air will continue to overspread wrn and ncntl Neb tonight.
347 AM CST Wed Dec 27 2017 (Today and tonight) A Winter Weather Advisory will remain in effect until 9 AM for the ongoing freezing drizzle. These areas of freezing drizzle and fog will continue to persist over the next few hours with temperatures right at or just below freezing in most areas along and north of Interstate 10. The cold temperatures will continue though with high temperatures in the low to mid 30s expected for this afternoon.
336 AM EST Wed Dec 27 2017 Arctic high pressure will be in control of the weather through the weekend.
133 AM EST Wed Dec 27 2017 Arctic high pressure will slowly build toward the region through late week.
245 AM EST Wed Dec 27 2017 An arctic cold front is continuing to push southward across eastern Kentucky this morning bringing crashing temperatures to the north of this boundary along with a few flurries.
431 AM EST Wed Dec 27 2017 Strong high pressure will be centered northwest and north of the forecast area through Thursday night. The high will direct cold air into the region. An area of low pressure along the front will bring light rain to much of the area this morning. Another low may bring light precipitation to the southeast section of the forecast area Thursday and Thursday night with freezing rain possible Thursday night.
1021 PM MST Tue Dec 26 2017 Broad upper trough continues across much of the CONUS, with the area under deep northwest flow. Surface analysis shows strong arctic high pressure across the Dakotas with southerly low level flow developing over the last few hours.
Increasing high/mid level clouds late Wednesday afternoon and evening, ahead of an approaching trough of low pressure.
Finally, added some areas of freezing fog overnight. Areas of light snow continue and expand as a new cold front arrives Wednesday night into Thursday.
257 AM CST Wed Dec 27 2017 Arctic high pressure will continue to slide southeast, centered over the upper Mississippi valley today, and the Great Lakes region tonight into Thursday.
400 AM CST Wed Dec 27 2017 High pressure ridge over the Red River valley at 09z and it will slowly move east. Cooler air will follow a short wave trough Thu night into Fri. Broad long wave trough over central and eastern Canada sharpens and shifts into eastern North America by Tue. Long wave ridge builds over western Canada.
Quiet weather is expected tonight, with low temperatures between 20-30 degrees across most of the High Country. Dry west-northwesterly flow aloft with high pressure along the California coast will continue for the next several days. Extended range models show high pressure weakening by the weekend with daytime temps cooling a bit for the Northland.
Mainly IFR to LIFR cig conditions expected tonight with moisture continuing to stream in this evening, then isentropic lift setting up later behind a cold front. A cold front will push through overnight and increase winds further, but will not clear out stratus deck. Persistent low stratus has remained across most of South Texas today, keeping temperatures on the cooler side this afternoon. An approaching cold front will move through the region overnight, bringing additional rain chances and colder weather to the region. Persistent CAA will allow temperatures to fall into the low to mid 40s most locations overnight, and upper 40s along the immediate coast.
Also, the low level wind shear previously at KCDS was removed.
437 AM MDT Mon Sep 18 2017 Updated Synopsis An upper level trof of low pressure will approach the region today.
As for the rest of the day, mid/upper level ridging will remain in place today, keeping a rather stout cap in place. No threat for any strong storms as wind shear will remain non-existent under the upper level ridge. Deeper troughing establishes itself across the West, with renewed ridging across the Great Lakes and Ohio Valley regions, while the tropics remain active across the western Atlantic and into the Eastern Seaboard. Initially, the ridging in the East will be weaker, allowing for some passing short wave energy to allow for the small threat of mainly diurnally driven showers and a few thunderstorms.
632 AM EDT Mon Sep 18 2017 A weak cold front over Indiana will move east over the local area and become stationary by this evening. The front will push to the south Tuesday as high pressure begins to build back over the region from the north. The high will then dominate the weather the second half of the week. The lower atmosphere will continue to moisten in advance of the front.
348 AM CDT Mon Sep 18 2017 Convection was occurring across southwest Kansas ahead of a mid level trough moving out of Colorado. Band of showers and thunderstorms had developed over central and north central Kansas in the nose of the low level jet within an area of good 850mb moisture transport. The warm front over northern Oklahoma is forecast to lift northward across Kansas through the day today as the mid level wave traverses the state. Temperatures will be affected by clouds and precipitation with north central and parts of northeast Kansas clearing out in the afternoon will experience the warmer temperatures. On Tuesday a strong mid/upper level trough will be moving over the northern Rockies and lifting out over the northern plains. This will cause the lee side trough to deepen and the pressure gradient to become maximized over eastern KS.
330 AM PDT Mon Sep 18 2017 Cooler weather this week with a chance of showers by mid-week. Current temperatures range from the lower 30s in the colder mountain valleys to the 60s to around 70 in the Central Valley. Initial cold front moves south through the area today and is expected to be mostly dry, though enough moistening of the airmass may take place for some sprinkles or light showers across the higher elevations of the northern Sierra Nevada into this evening.
This increased moisture surge will keep some scattered showers and possibly isolated thunderstorms in the forecast for today as the moisture moves around the periphery of the H5 high pressure system. This ridge of high pressure will still remain in place, however, and think that POPs will remain somewhat limited due to subsidence.
243 AM PDT Mon Sep 18 2017 Mainly average temperatures are expected for today before a trough moves through the region by Tuesday morning and lowers temperatures a little.
Temperatures will climb into the mid to upper 80s across most of the area, with the cumberland Plateau in the low 80s. Showers and thunderstorms will pop in and out of the forecast throughout the work week as we keep weak high pressure influences around the Tennessee Valley. Weak high pressure remains entrenched across the region, so we can expect relatively benign weather and generally light winds the next 24 hours & beyond.
337 AM CDT Mon Sep 18 2017 (Today and Tonight) An upper level ridge will remain centered across South Texas today, with mainly zonal flow across West Central Texas. High resolution models indicate a disturbance moving east across West Texas this afternoon, along the northern periphery of the ridge. in the low to mid 90s. Mild overnight temperatures are forecast, with lows mainly in the low 70s.
Early afternoon water vapor loop showed the upper trough axis entering western WY and northern UT. Scattered showers and thunderstorms will taper off from west to east later this evening across the plains as the upper trough moves through the CWA. A strong Pacific cold front will race east across WY Tuesday afternoon and western NE Tuesday night. Scattered showers will accompany the front, along with cooler temperatures for portions of south-central southeast WY. It will be a little cooler Weds in the wake of a Pacific cool front. Looking breezy to windy as well as favorable southwesterly upper flow sets up over the region ahead of a digging upper trough over the Pacific northwest.
High pressure continues across the area at this time. The cold front remains just northwest of Arkansas and chances for rain will be confined to mainly far northwestern AR. Upper ridge across the Gulf states will keep the front from making significant headway into the area, so confident highest chance of rain and thunder will remain across the northern tier or two of counties through the rest of today.