Aikyam-Lab/Synoptic-Bench huggingface dataset:
Have seen an improvement through the afternoon hours across central and eastern Missouri, but am a bit concerned that atmosphere was unable to adequately mix out the low level moisture. Low level jet increases overnight ahead of a subtle cold front that moves through the area tomorrow morning. With that said, still looks like a very pleasant day for December with 925 hpa temperatures of 11-13 C leading to highs in the lower 60s F.
328 PM MST Tue Dec 8 2020 Quiet weather expected in the short term as CO remains under a flattening upper ridge of high pressure. Temperatures may be a degree or two cooler out west as heights aloft drop a bit in response to the northern stream trough approaching through the NW but overall changes appear to be subtle.
430 PM MST Tue Dec 8 2020 Water vapor shows upper ridge dominating the western CONUS, with upper trof beginning to influence the Pac NW and cut off low off the Baja CA. Upper ridge will maintain control through much of Wednesday, although temps tomorrow will be a few degrees cooler as thermal ridge axis shifts east and cold front approaches from the west. Cold front moves through late Wednesday and Wednesday night as aforementioned Pac NW trof quickly translates through the Northern Rockies.
BW Chattanooga Airport, TN 30 59 36 63 39 / 0 0 0 0 0 Knoxville McGhee Tyson Airport, TN 28 54 35 60 37 / 0 0 0 0 0 Oak Ridge, TN 28 55 33 59 37 / 0 0 0 0 0 Tri Cities Airport, TN 24 51 30 58 34 / 0 0 0 0 0.
The upper trough currently exiting the southeast CONUS will continue to progress eastward over the Atlantic tonight, with an upper ridge building over the Mississippi and Lower Ohio valleys through Wednesday afternoon. Highs Wednesday will then be in the mid to upper 60s, about 10 degrees warmer than today's highs.
1241 AM EST Wed Dec 9 2020 The Mid Atlantic and Carolinas will remain between low pressure off the East Coast and high pressure over the Ohio and Tennessee Valley through Wednesday.
1257 AM EST Wed Dec 9 2020 Temperatures below freezing this morning, will warm into the 50s today as SW winds develop. A warming trend is expected late week through the weekend, as an upper ridge expands over the area.
Lows tonight will be slightly warmer with much of the area only falling into the low 40s.
Given the lack of any meaningful downsloping low level winds, afternoon highs will only be a degree or two warmer than yesterday, with widespread upper 60s and possibly a few lower 70s.
220 AM CST Wed Dec 9 2020 With the low level moisture now scoured away, all we will be dealing with over the next 2 days will be some mid to high level moisture in the form of some high clouds. A decent 850mb thermal ridge will be sliding south today. Latest 00Z RAOBs indicate 850mb temps in the teen up in the northern Plains which is in the heart of the thermal ridge that will be heading our way today. So as this warmer air advects into the area throughout the day today, we should see a pretty good boost in highs.
Possible a few slick spots may develop as the temperature cools below freezing late tonight. This is all in response to strong low pressure and its upper wave moving across Ontario into Quebec for today into Wed. The warm advection will leave a mild airmass in place for Wed despite the passage of a weak cold front Wed AM.
1236 AM EST Wed Dec 9 2020 High pressure will prevail through late week.
118 AM EST Wed Dec 9 2020 High pressure builds into the region tonight then slides south Wednesday with weak and dry front pushing across the area Wednesday night. High pressure builds back across the region for the latter half of the week.
1104 PM CST Tue Dec 8 2020 A large mean ridge of high pressure continued to build across the region today. Cirrus was blowing off the western ridge and spreading overhead. For tomorrow, even warmer conditions are expected with highs in the 60s and low 70s. A large upper level cut off low pressure system was located off of the southern California coast today.
1022 PM MST Tue Dec 8 2020 Water vapor shows upper ridge dominating the western CONUS, with upper trof beginning to influence the Pac NW and cut off low off the Baja CA. Upper ridge will maintain control through much of Wednesday, although temps tomorrow will be a few degrees cooler as thermal ridge axis shifts east and cold front approaches from the west. Cold front moves through late Wednesday and Wednesday night as aforementioned Pac NW trof quickly translates through the Northern Rockies.
Deep northwest flow continues to dominate across the TN Valley and Southern Appalachians this morning with high pressure prevailing beneath across much of the southeast CONUS. Fortunately it looks as if this sky cover will inhibit widespread fog (freezing fog) this morning, although wouldn't rule out some isolated occurrences in some of the river valleys.
CDG Chattanooga Airport, TN 59 36 63 39 63 / 0 0 0 0 0 Knoxville McGhee Tyson Airport, TN 54 35 60 37 62 / 0 0 0 0 0 Oak Ridge, TN 55 33 59 37 61 / 0 0 0 0 0 Tri Cities Airport, TN 51 30 58 34 60 / 0 0 0 0 0.
945 PM MST Tue Dec 8 2020 High pressure will remain across the region through midweek.
245 AM CST Wed Dec 9 2020 An upper level trough was situated across parts of the Southeast US extending NNE into the Atlantic while northwest mid/upper flow prevails upstream across the central CONUS. Meanwhile, another upper level trough was situated off the California/Baja coast over the Pacific. Another mild day is anticipated across the Central Plains today as a mid/upper ridge translates eastward across the region.
357 AM EST Wed Dec 9 2020 High pressure will prevail through late week.
Dry and warmer weather returns to end the work week. With northwest flow aloft, the next trough will dive southeast through the region today. Model soundings show substantial mid layer saturation with the approach of the trough.
High pressure will reign for this TAF period bringing VFR conditions for all sites throughout the period. Upper level ridging will settle over the region tonight and into tomorrow, which will provide clear skies and light winds for all TAF sites throughout the period. Low level flow will veer and thermal ridging will expand across the region tomorrow with fcst low level temps expected to rise near seasonal extremes.
Winds have come down to mostly calm across the area, and with temps below freezing, dew point depressions into the low single digits, and mostly clear skies in place frost is already starting to develop.
1034 PM MST Tue Dec 8 2020 Quiet weather expected in the short term as CO remains under a flattening upper ridge of high pressure. Temperatures may be a degree or two cooler out west as heights aloft drop a bit in response to the northern stream trough approaching through the NW but overall changes appear to be subtle.
Our run of quiet weather will continue today amid plenty of sun and warming temperatures as a dampening mid/upper level ridge traverses the area. Temperatures are expected to top out in the low/mid 70s. Weak SW SFC flow is expected to gradually develop this afternoon/tonight as high pressure over the Gulf shifts off to the east, allowing at least a limited influx of SFC MSTR to begin. For now, have inserted patchy/areas of fog where the highest probabilities reside. Once any fog that does develop erodes, another sunny and warm afternoon is expected on THU downstream of an approaching upper trof (currently the upper low west of the Baja). The upper trof is progged to continue slowing translating E on FRI, nudging a slow moving CDFNT across central/eastern TX FRI afternoon and evening.
Low-level thermal ridge solidly in place upstream across the plains, which the KOAX 00z sounding sampled well (51F at 850 mb). Drier air mass is in place today will yield more insolation, better mixing and thus warmer high temperatures, which will reach close to 60F across far southern Iowa. By Thursday, dry cold front will enter northern IA by midday and into central IA by sunset.
315 AM CST Wed Dec 9 2020 Weak upper level ridging this morning will give way to a more zonal flow developing by this afternoon. At the surface, high pressure will slide across the area this morning, with a trough digging down the lee of Rockies this afternoon. WAA develops ahead of this trough, with H925 temperatures in the +6C to +12C range this afternoon. The trough/cold front tracks across the area tonight, with cooler high pressure nosing in on Thursday. High temperatures today will range from the lower 50s east to the mid 60s southwest, with lows tonight in the upper 20s to lower 30s.
Several cirrus clouds were streaming in from the north early this morning as a mid and upper level ridge progressed eastward toward the Southeast.
335 AM CST Wed Dec 9 2020 Several cirrus clouds were streaming in from the north early this morning as a mid and upper level ridge progressed eastward toward the Southeast.
Drizzle with isolated slick spots cannot be ruled out before sunrise but recent trends suggest that the threat for freezing precipitation is low. Model guidance agrees that moisture will be limited in most places until the cold frontal passage when most of the showers are expected. Snow levels are starting off high and will lower with the cold front. The Glacier Region remains the main area with the highest likelihood for accumulating snow through this evening so a winter weather advisory remains in effect. High pressure briefly returns for Thursday with dry conditions expected.
We will have one more benign day today as the ridge aloft holds through about midday before shifting out to the Plains. Much of the prognostication in the near term has been focused on the low pressure system currently residing off the SoCal/Baja coast. A much stronger upstream jet is approaching the Pacific Coast which will allow this low to get hooked back into the Westerlies and progress eastward. The closed low will arrive in the Southwest by early Thursday. Much of this lift will be needed for top down saturation with most of the measurable precipitation likely falling in the higher terrain.
A gradual warming trend to continue through the short term period with highs today forecast to climb into the low to mid 70s this afternoon. Trended slightly warmer than guidance on temps today and Thursday based on observed temps biasing higher than forecast over the past several days. Otherwise lows tonight to fall into the upper 30s to lower 40s with highs on Thursday in the low to mid 70s.
/issued 407 AM CST Wed Dec 9 2020/ Upper-level ridging will keep temperatures well above seasonal norms today with highs pushing the mid 70s in many locations. Lows are expected to remain above freezing across most of the region tonight. This abnormal warmth will last into Thursday as SW flow aloft increases ahead of an approaching shrtwv trof which will quickly lift into AZ/NM throughout the day. Increasing cloud cover will reach the western CWA early Thursday where temps will be a few degrees cooler than the rest of the region.
Dry and warmer weather returns to end the work week. With northwest flow aloft, the next trough will dive southeast through the region today. Model soundings show substantial mid layer saturation with the approach of the trough. High pressure will then begin to nose into the forecast area by the day on Thursday.
329 AM MST Wed Dec 9 2020 A cold front will bring cooler air into North-central Montana later today.
327 AM CST Wed Dec 9 2020 An upper level ridge over the Rockies will shift east into the central CONUS with unseasonably warm temperatures. Went on the higher side of the suite of temperature guidance for the next couple of days which has worked out well recently, especially with a west to southwest sfc wind. Highs in the 60s and low 70s are expected with slightly warmer readings expected Thursday.
Some WTM stations in the nrn Rolling Plains were even in the low 50s as westerly breezes were locally enhancing downsloping and mixing.
547 AM EST Wed Dec 9 2020 The Lower Keys continues to be just on the eastern most edge of a strato-cu deck that has been slowly sliding southward overnight. This in combination with the slightly west of north trajectory over relatively warmer and deeper waters, has kept Key West in a near steady state. Meanwhile, across the Upper and Middle Keys the wind is passing over much shallower and cooler waters as well as off the mainland. A high pressure over the western Gulf of Mexico will slowly move eastward through the next couple days.
342 AM CST Wed Dec 9 2020 Long wave through enveloping 2/3rds of the conus will start to slide east with the ridge to our west moving towards the Lower MS Valley but it will deamplify. While our next weather maker will still be the closed low currently west of the Baja. The low sits there until Wednesday night when it finally gets kicked to the northeast and begins to merge with the northern stream.
425 AM EST Wed Dec 9 2020 Trough enters northern New York today then exits into New England tonight.
While we probably won't mix to 850 mb, afternoon highs should still be in the 70s deg F for most locations because of the warmer low-level thermal profile.
407 AM CST Wed Dec 9 2020 Upper-level ridging will keep temperatures well above seasonal norms today with highs pushing the mid 70s in many locations. Lows are expected to remain above freezing across most of the region tonight. This abnormal warmth will last into Thursday as SW flow aloft increases ahead of an approaching shrtwv trof which will quickly lift into AZ/NM throughout the day. Increasing cloud cover will reach the western CWA early Thursday where temps will be a few degrees cooler than the rest of the region.
637 AM EST Wed Dec 9 2020 High pressure will prevail through late week.
/Issued 401 AM CST Wed Dec 9 2020/ Record temperatures continue to be the main story in the short term as warming at 850 mb combined with abnormally dry air and slight downslope winds combine to push temperatures into the lower 70s across portions of eastern Oklahoma and the Arkansas River Valley.
546 AM CST Wed Dec 9 2020 With surface and upper-level high pressure prevailing areawide, VFR conditions expected across area terminals through the forecast period ending 10/12Z. A gradual warming trend to continue through the short term period with highs today forecast to climb into the low to mid 70s this afternoon. Trended slightly warmer than guidance on temps today and Thursday based on observed temps biasing higher than forecast over the past several days. Otherwise lows tonight to fall into the upper 30s to lower 40s with highs on Thursday in the low to mid 70s.
Another warm day today before a storm system brings cooler temperatures and a good chance of showers tonight into Thursday, with isolated thunderstorms possible as well.
Weak upper level ridging this morning will give way to a more zonal flow developing by this afternoon. At the surface, high pressure will slide across the area this morning, with a trough digging down the lee of Rockies this afternoon. WAA develops ahead of this trough, with H925 temperatures in the +6C to +12C range this afternoon. The trough/cold front tracks across the area tonight, with cooler high pressure nosing in on Thursday. High temperatures today will range from the lower 50s east to the mid 60s southwest, with lows tonight in the upper 20s to lower 30s.
Look for generally fair weather for the next two days with in the low 60s today and mid 60s on Thursday. Any clouds may be limited to the northeast, closer to the base of the mean trough in place aloft.
A second cold front was over SE BC. Compressional warming ahead of the front will promote temps from the low 50s NW to the low 60s SE. A thin ridge of high pressure moves over the area Thu.
The return of a more southerly flow tomorrow will help to keep temps on the warmer side of seasonal norms. Per the latest runs of a slightly slower track of the upper low from the W/SW. rain chances should hold off for SE TX until early Fri morning with the passage of the pre-frontal trof.
The upper level ridge will begin to flatten today as the next upper trough comes ashore over the Pacific Northwest. This upper trough will deepen across the western United States on Thursday with a strong cold front pushing through late tonight into Thursday morning. Highs on Thursday will be around 15 to 20 degrees cooler behind this cold front and it will be unpleasantly windy.
Readings will be in the upper 30s across the Golden Triangle to the lower 40s elsewhere.
High pressure sliding through the region later today brings lighter and somewhat variable winds through the afternoon and evening, helping to lessen fire weather concerns. Winds eventually turn southerly at the surface and will increase overnight as the high pressure continues to the east and the surface pressure gradient tightens ahead of Thursday morning's cold front. Although still above average, slightly cooler temps move into the region for Thursday. A cold front treks through early Thursday morning, ushering in cooler air and turning flow more northerly. Despite this frontal passage, still expect highs above normal, thanks to some lingering warmer air aloft. Thus, lowered highs a couple of degrees from the previous forecast (mainly across south central SD) with guidance speeding up the cold fropa and cooler air aloft.
526 AM CST Wed Dec 9 2020 Today, an upper-level ridge will shift eastward across the central U. The upper-level ridge is expected to continue eastward into the eastern U. on Thursday while an upper-level cutoff low interacting with an approaching northern stream upper-level trough begins to exit the southwest U. In response to associated low-level height falls at the lee of the Rocky Mountains in advance of the cutoff low/trough, low-level flow in the Midwest will begin to back to the south causing WAA to ensue across the region. This evolution should allow Thursday's high temps to be similar to today's, possibly warmer depending on extent of upper-level cloud coverage and if low- level flow can veer slightly throughout the day.
With the low level moisture now scoured away, all we will be dealing with over the next 2 days will be some mid to high level moisture in the form of some high clouds. A decent 850mb thermal ridge will be sliding south today. Latest 00Z RAOBs indicate 850mb temps in the teen up in the northern Plains which is in the heart of the thermal ridge that will be heading our way today. So as this warmer air advects into the area throughout the day today, we should see a pretty good boost in highs.
604 AM EST Wed Dec 9 2020 Trough enters northern New York today then exits into New England tonight.
Winds have come down to mostly calm across the area, and with temps below freezing, dew point depressions into the low single digits, and mostly clear skies in place frost is already starting to develop. High pressure should be emerging off of the Mid Atlantic coast, with good southerly flow off of the GOMEX across the CWA.
Another mild day expected today before a cold front is expected to cross the state tonight. High pressure at the surface keeps winds mostly 15 mph and under through the afternoon. In the northern tier highs in the low 40s expected. Further south, conditions will be breezy behind the cold front as pressure rises and increased 850mb flow may gust winds up to 35 mph at times overnight. Cooler and more seasonable temperatures are expected with this pattern. High pressure builds behind the previous front on Thursday, with a pressure gradient from the low to the east keeping conditions breezy in the central/east during the day. A cold front will push west to east tonight, shifting winds to the northwest and bringing MVFR/IFR ceilings.
314 AM CST Wed Dec 9 2020 Upper ridging will move across the area as light southwest surface flow brings in some mild air through Thursday.
(See discussion below) Previous Discussion: /Overnight through Wednesday/ High pressure aloft and very dry air through a deep layer of the atmosphere will result in a clear sky tonight and a sunny sky on Wednesday. Highs will range from the lower 70s in the northeast to the upper 70s across the southwest.
Today Through Thursday Night Mesoanalysis indicated broad upper-lvl ridging over the Rockies w/ a meandering cutoff low over the Baja of CA. Modest upper N/Wrly flow was noted over the Natural State invof the downstream portion of upper ridging. WAA will continue to intensify and promote an even warmer afternoon on Thurs, w/ current guidance suggesting low 70s over much of the state.
Moderate to breezy south winds can be expected on Thursday as the pressure gradient strengthens along the lower Texas coast. High temperatures today and Thursday will range from the 70s along the coast to the low to mid 80s inland under mostly sunny skies.
943 AM EST Wed Dec 9 2020 High pressure over the Ohio Valley will move east on Thursday, with a warm, southerly flow expected through the remainder of the week.
914 AM EST Wed Dec 9 2020 The Florida Keys are sitting at the base of a large mid and upper level trough situated over the Atlantic just off the eastern seaboard. Temperatures dipped into the low to mid 50s in the upper Keys this morning, and in the upper 50s across most of the lower and middle Keys.
/issued 314 AM CST Wed Dec 9 2020/ Upper ridging will move across the area as light southwest surface flow brings in some mild air through Thursday.
A cold front will bring cooler air into North-central Montana later today.
Mid- level ridging currently present over the Four Corners region will build into the Plains today making for another warm December day. The pattern begins to transition on Thursday as the cutoff low starts to progress eastward with a surface cold front moving into the CWA from the northwest. Highs on Thursday will be dependent on how quickly this front moves through the CWA; highs ahead of the front will be in the low 60s with temperatures topping out in the mid to upper 50s behind the front.
An upper level trough is currently pushing into the PacNW pushing a cold front into the far NW part of the state. We are also seeing some high clouds in southern areas associated with a closed off upper level low located off the Baja coast. The upper level low will become an open wave today and push east as the weakening front slowly push south through the area. As the trough pushes into the northern Rockies it will bring some increased northerly and easterly flow but currently winds look to remain overall weak with gusts generally staying below 20 mph. Short wave riding will briefly build in for early Thursday before we see a short wave trough and cold front track over northern portions of the area.
522 AM CST Wed Dec 9 2020 An upper level trough was situated across parts of the Southeast US extending NNE into the Atlantic while northwest mid/upper flow prevails upstream across the central CONUS. Meanwhile, another upper level trough was situated off the California/Baja coast over the Pacific. Another mild day is anticipated across the Central Plains today as a mid/upper ridge translates eastward across the region. The upper low off the California coast is progged to move into the Southwest States tonight before emerging across the Southern Rockies as we move into Thursday. Highs on Thu are expected to remain well above normal for mid December, however cooler compared to values on Wed.
426 AM PST Wed Dec 9 2020 A weak and shallow cold front is pushing into the Cascades this morning with light precipitation that appears to be falling as rain up to about 7,000 foot elevations. We've been closely watching surface temperatures along and near the Cascades, especially in the Chemult area, to see if precipitation falls in the areas with below freezing temperatures. It is possible that some sheltered low elevation cold pockets such as the Fish Lake and Howard Prairie areas as well as areas along and near Highway 97 around and in Chemult could see a little bit of freezing rain or freezing drizzle this morning. High pressure will build in rapidly this afternoon with wind gusts of 20 to 40 mph from the northeast across the mountains and through the gaps, especially from the Cascades westward.