Aikyam-Lab/Synoptic-Bench huggingface dataset:
with low temperatures tonight bottoming out in the single digits and highs tomorrow only reaching the lower to middle 20s. Upper low continues to spin across Illinois this evening with pinwheeling vort lobe over northern Illinois sagging south towards central Illinois. 20z/2pm water vapor imagery shows a deepening long-wave trough extending from Ontario southward to the Gulf Coast. A potent wave embedded within the trough over eastern Iowa/northwestern Illinois has been responsible for the development of diurnal clouds and scattered flurries across central Illinois today. Low temperatures tonight will drop into the single digits, while highs on Friday struggle to reach the lower to middle 20s. Upper heights will rise in earnest over the weekend as the trough departs and ridging takes hold across the central/eastern CONUS.
324 AM EST Fri Dec 25 2020 Snow and cold conditions are expected today with an upper level low.
1028 PM MST Thu Dec 24 2020 A ridge of high pressure over the Great Basin today will push east and flatten across the forecast area through tomorrow night. As the ridge moves over the forecast area tomorrow expect surface inversions to develop with warming temperatures over the higher terrain and cold, more stagnant air remaining entrenched over favored trapped valley locations.
However, as the deep, negatively tilted longwave trough and closed mid level circulation shift overhead, lapse rates will remain very steep overnight. Garuckas Chattanooga Airport, TN 22 31 19 46 27 / 20 0 0 0 0 Knoxville McGhee Tyson Airport, TN 21 26 17 42 26 / 50 20 10 0 0 Oak Ridge, TN 21 27 17 42 25 / 50 20 10 0 0 Tri Cities Airport, TN 19 22 12 37 21 / 90 40 10 0 0 NC.
157 AM EST Fri Dec 25 2020 A strong cold front will move offshore during the early morning hours. Early this morning: Strong cold advection has taken hold across the region behind the cold front that has moves east of the forecast area. Overnight low temperatures will be in the lower 20s.
1008 PM MST Thu Dec 24 2020 Upper ridging will continue build in from the west through Christmas, tomorrow. Upper ridge will flatten as a series of weak waves push through ahead of the next Pacific system.
339 AM EST Fri Dec 25 2020 A deep tropospheric high amplitude trough sweeping towards the eastern CONUS has driven a strong cold front through the Florida Keys this morning. Low temperatures tonight will drop into the low 50s, and possibly even dip a degree or so colder.
355 AM EST Fri Dec 25 2020 High pressure will continue to build in behind the cold front today with breezy northwesterly winds ushering in much colder drier air. Freezing temperatures are expected from Pasco county northward with a hard freeze across parts of Levy county where minimums are expected to fall into the middle 20s. High pressure across the southeast U.
High pressure aloft will move across Utah tonight through early Friday. Mid level ridging centered across the forecast area is maintaining dry and cold conditions this Christmas Eve. High clouds associated with an upper trough along the California coast have spread across much of the area and will remain in place through Christmas morning as this trough passes south of the area.
158 AM MST Fri Dec 25 2020 H5 ridging continues across Wyoming this Christmas Day, with modest westerly flow continuing across the state. The Big Horn Basin and the I-25 corridor remain warmer, with highs in the 40s this afternoon.
Despite mostly clear skies today, highs will struggle to rise above freezing.
However, as the deep, negatively tilted longwave trough and closed mid level circulation shift overhead, lapse rates will remain very steep overnight. Deep upper trough producing a cyclonic flow across the area will keep areas of MVFR/low VFR ceilings across TRI and TYS throughout most of the forecast period until around 23Z to 02Z this evening. However, as the deep, negatively tilted longwave trough and closed mid level circulation shift overhead, lapse rates will remain very steep overnight. Merry Christmas! Garuckas Chattanooga Airport, TN 31 19 46 27 53 / 0 0 0 0 0 Knoxville McGhee Tyson Airport, TN 26 17 42 26 51 / 20 0 0 0 0 Oak Ridge, TN 27 17 42 25 51 / 20 0 0 0 0 Tri Cities Airport, TN 22 12 37 21 51 / 30 10 0 0 0 NC.
A deep upper trough across the central and southern Appalachians. For Tonight, upper trough moves well northeast of the area with flurries ending and clouds clearing area-wide. For Today through Tonight, wind chills will remain dangerous over the higher terrain.
A weak low pressure system will cross the region Christmas morning bringing mostly cloudy skies and a few mountain flurries. In advance of an approaching weak low pressure system clouds were increasing and thickening across northern Arizona during the evening. The cloud cover will help keep things a bit warmer than last night but still expect chilly lows for Christmas morning. As the weak system crosses the state Christmas morning, there is a slight chance of flurries over the higher terrain.
157 AM MST Fri Dec 25 2020 Upper ridge and high pressure will be over the forecast area today.
539 AM EST Fri Dec 25 2020 Snow and cold conditions are expected today with an upper level low. Dry weather returns Saturday under high pressure. expect areas of snow to continue through the day as a mid/upper level low moves across the Upper Ohio Valley region. Areas of mainly light snow should taper off overnight as the upper low weakens into a trough and exits the area. Mainly dry weather is expected Saturday as weak sfc ridging builds under cold NW flow aloft.
437 AM MST Fri Dec 25 2020 H5 ridging continues across Wyoming this Christmas Day, with modest westerly flow continuing across the state. The Big Horn Basin and the I-25 corridor remain warmer, with highs in the 40s this afternoon. The next trough flattens the H5 ridge on Saturday, with increasing chances for snowfall across the western mountains. With only orographic lift and minimal jet lift, feel the models are overestimating snowfall for the higher Teton Peaks for Saturday.
320 AM CST Fri Dec 25 2020 Surface ridging situated across the region will shift off to the east today, and in an evolving warm air advection regime it will be a much milder day as winds become southerly. Low pressure sliding across central Canada will pull a weak boundary through our area tonight. This will reinforce colder air over our area with lows tonight in the lower teens, with some guidance suggesting stratus feeding in behind the boundary.
455 AM CST Fri Dec 25 2020 Surface ridging situated across the region will shift off to the east today, and in an evolving warm air advection regime it will be a much milder day as winds become southerly. Low pressure sliding across central Canada will pull a weak boundary through our area tonight. This will reinforce colder air over our area with lows tonight in the lower teens, with some guidance suggesting stratus feeding in behind the boundary.
227 AM MST Fri Dec 25 2020 Western NOAM ridge will shift east and allow for mild and dry conditions through Sat. Thermal ridge will time over the area this afternoon, with mostly sunny skies expected. Backdoor cold front will settle into the FA tonight, with low clouds and fog possible in the eastern third.
The high will gradually shift to the south and east today, allowing for onshore flow and moisture to gradually return by tonight.
An upper level ridge will move out of the Central Rockies today and through the Central High Plains tonight. As for temperatures, highs today look to reach around 60 degrees with lows tonight ranging from the low 20s across west central Kansas to upper 30s across south central Kansas.
Despite a very dry airmass tonight (dewpoints in the teens), light south winds should keep the boundary layer mixed enough to limit radiational cooling, as the high clouds diminish. Most areas will see overnight lows by daybreak Saturday in the low to mid 30s.
Today Through Saturday Night A cold morning is ongoing early this Christmas morning as a new cold front has brought even colder. Expect lows tonight in the low 20s to low 30s as winds will switch back to the south. These SRLY winds will also bring increasing moisture ahead of the next cold front.
Trough moving east from the Pacific will spread rain and mountain snow into the area through the day, continuing through Saturday morning. Heavy snow will develop this morning mainly over the higher elevations of the Coast Range and Shasta County mountains, although accumulations of 4 to 8 inches are possible along Interstate 5 north of Redding from Sims to Dunsmuir. 8 to 14 inches of snow is expected at pass level with up to 2 feet over the higher peaks.
348 AM CST Fri Dec 25 2020 Early this Christmas morning, a dry warm front continues to slowly drift across the state, currently draped over central North Dakota. Breezy conditions will develop behind the warm front this afternoon across the southern James River Valley. As the ridge deamplifies, clouds will increase tonight along with the potential for some fog, with the best chances across the Turtle Mountains and James River Valley. The broad ridge over the Northern Plains continues to flatten as a new highly amplified ridge begins to pop up over the west coast of Canada.
Notable warm up expected Saturday beneath expanding low level thermal ridge.
The period will start with surface ridging over the southeast CONUS and rather zonal flow aloft.
Another lobe of the upper trough will swing southward today, bringing a bit of additional cloud cover and more chances of snow to the area.
A cold front will move southward through the region Friday night into Saturday and bring light precipitation to mainly the higher terrain from Fresno County northward.
SHORT TERM (Now through Saturday): The surface ridging centered over Deep South TX and the RGV brining the freezing conditions to the region will start sliding eastwards later today and tonight, This will allow the surface winds to shift around from the E-SE later today and tonight. The low atms humidity levels will allow for pretty good radiational conditions once again tonight especially over the northern Ranchland. However, the returning E-SE low level flow will allow the surface dewpoints to rebound enough especially across the southern and coastal counties to limit the potential for freezing temps. Some isold freezing temps may be possible across the northern Ranchland counties late tonight through early Sat morning.
413 AM CST Fri Dec 25 2020 The current weather pattern across the CONUS is defined by a deep 500 mb low centered over the Ohio Valley with an accompanying highly amplified mid to upper level trough across much of the center and eastern CONUS. The warming trend continues into Saturday as a warm front lifts northward through the region. High temperatures for the I-70 corridor and south will be around 50 to even the mid 50s with cooler high temperatures as you travel northward toward the Iowa border, where highs will only reach the low 40s north of the warm front.
One more 500 mb vorticity lobe will rotate south across Indiana on the back side of the low this morning. Some of the high res cams models pick up on the flurries affecting Indiana and Illinois. An area of low clouds and flurries will accompany the 500 mb disturbance across the lower Ohio Valley through midday. The core of the low level cold air will pass over Indiana today, where 850 mb temps will be near minus 20 this morning. With the clouds and flurries, sfc temps will be hard pressed to get out of the lower 20s in sw Indiana. Southwest winds on the back side of high pressure over the southern Appalachians will bring milder temps.
356 AM MST Fri Dec 25 2020 25/00Z H500 map continues to show an amplified pattern in place with a deep trough moving through E. ridging dominating the Rockies. The ridge will slowly move into the High Plains today as the upstream system makes its way inland. Chances of mixing this warmer air down to valley areas will be a difficult task and the large spread of guidance temperatures is not a good exercise in confidence building. Overall stayed near previous forecast if just a bit cooler in some areas with the cold pools in the larger basins expected to stay anchored in place.
As the deep trough to our east continues to track away from the area, this front will move into the western portions of the area as a warm front. This will result in highs ranging from the low 30s across the eastern forecast area to the low 40s over the west. The warmer airmass continues to move in tonight, leading to a warmer night than we are currently observing.
Dry northwesterly upper flow today as an upper ridge builds east across the central Rockies and central Plains states by tonight. The upper trough will continue tracking east Saturday with a zonal to northwesterly upper flow setting up behind the departing upper trough Saturday into Saturday night. Lee enhanced cirrus or cirrostratus associated with this upper trough may possibly impact the Panhandles Saturday night resulting in partly cloudy or even mostly cloudy skies Saturday night. Surface lee trough over the central and southern Rockies today will allow for warmer downsloping west to southwest winds across the forecast area.
A warm front is draped across the western Dakotas with temps in the 30s in the western part of the state this morning. This will help to ensure some cooler temperatures compared to today's stick around through the daytime period.
Slightly cooler high temperatures are in place for Saturday.
/issued 340 AM CST Fri Dec 25 2020/ Arctic air has invaded the Mid-South and is being reinforcing by a secondary cold front early this morning. The synoptic pattern remains quite amplified over much of the CONUS, reflecting a positive PNA, split-flow regime with an anomalously deep trough over the TN Valley. It will remain quite chilly today with temperatures struggling to reach the freezing mark in portions of west TN despite full insolation. Elsewhere, expect highs in the low/mid 30s.
Very cold weather today will persist with highs mostly in the lower 20s. The latest WPC high resolution models generally morph the activity into a north/south single band after the low moves on land. As with the past 4 lake effect events this early winter season, warm air advection will increase rapidly in the low layers and will cause inversions heights to fall and subsequently cause activity to rapidly diminish this afternoon.
340 AM CST Fri Dec 25 2020 Arctic air has invaded the Mid-South and is being reinforcing by a secondary cold front early this morning. The synoptic pattern remains quite amplified over much of the CONUS, reflecting a positive PNA, split-flow regime with an anomalously deep trough over the TN Valley. It will remain quite chilly today with temperatures struggling to reach the freezing mark in portions of west TN despite full insolation. Elsewhere, expect highs in the low/mid 30s.
418 AM MST Fri Dec 25 2020 Western NOAM ridge will shift east and allow for mild and dry conditions through Sat. Thermal ridge will time over the area this afternoon, with mostly sunny skies expected. Backdoor cold front will settle into the FA tonight, with low clouds and fog possible in the eastern third.
533 AM CST Fri Dec 25 2020 The current weather pattern across the CONUS is defined by a deep 500 mb low centered over the Ohio Valley with an accompanying highly amplified mid to upper level trough across much of the center and eastern CONUS. The warming trend continues into Saturday as a warm front lifts northward through the region. High temperatures for the I-70 corridor and south will be around 50 to even the mid 50s with cooler high temperatures as you travel northward toward the Iowa border, where highs will only reach the low 40s north of the warm front.
Temperatures should fall fairly quickly at sunset given dry air and light winds, but lows should be several degrees warmer than this morning.
Early this Christmas morning, a dry warm front continues to slowly drift across the state, currently draped over central North Dakota. Breezy conditions will develop behind the warm front this afternoon across the southern James River Valley. As the ridge deamplifies, clouds will increase tonight along with the potential for some fog, with the best chances across the Turtle Mountains and James River Valley. The broad ridge over the Northern Plains continues to flatten as a new highly amplified ridge begins to pop up over the west coast of Canada.
This is due to the strong cold front that pushed through our area last night. The higher wind speeds are due to the strong thermal gradient that exists across the region, driving a tight pressure gradient. As high pressure regains control, winds should begin to subside and clouds begin to diminish, but this will not likely begin to materialize until this evening Multiple marine hazards remain in effect in the wake of last night's cold front.
Model soundings support highs just a little warmer on the plains, mainly upper 50s, despite fairly light winds. The low spots may lag behind a little. On Saturday, a flat upper level ridge will be over the Central and Northern Plains States with a moderate westerly flow aloft over Colorado.
A warm front will begin to gradually increase moisture in the atmosphere over Idaho and Montana later tonight, focusing primarily on Clearwater County, Idaho and then into NW Montana. As such Winter Weather Advisories will be issued for the Kootenai/Cabinet Region (Libby, Troy, and Eureka) and the West Glacier Region (West Glacier, Polebridge & Swan Lake). We may expand this advisory area into the Lower Clark Fork region including I-90 and Lookout Pass if models maintain lower snow levels and this undoubtedly be evaluate further by the day shift. The dynamic of this passing storm system will change from steady light snow (warm front) to a more showery regime as a weak cold front moves over the area and the atmospheric flow turns northwesterly.
Lows should be in the lower teens for inland areas.
characterized by pronounced troughing aloft over the eastern CONUS and pronounced ridging aloft over the western CONUS. Today-Saturday: Expect above normal temperatures and tranquil weather and as the pronounced upper level ridge over the western CONUS de-amplifies and progresses eastward into the central CONUS.
Believe freezing temperatures will be widespread north of Highway 190. No weather issues through tomorrow as high pressure moves across the area. Today will be much warmer with afternoon temperatures climbing well into the 50s.
/issued 403 AM CST Fri Dec 25 2020/ SHORT TERM (Now through Saturday): The surface ridging centered over Deep South TX and the RGV brining the freezing conditions to the region will start sliding eastwards later today and tonight, This will allow the surface winds to shift around from the E-SE later today and tonight. The low atms humidity levels will allow for pretty good radiational conditions once again tonight especially over the northern Ranchland. However, the returning E-SE low level flow will allow the surface dewpoints to rebound enough especially across the southern and coastal counties to limit the potential for freezing temps. Some isold freezing temps may be possible across the northern Ranchland counties late tonight through early Sat morning.
In response to the approaching cold front, surface winds Saturday, from the south or southwest, may be gusty; but, winds should remain below Wind Advisory levels. Another Cold Front and Possible Rain.
High temperatures should be another notch warmer Saturday, mostly upper 60s.
The strong low pressure system continues to march eastward which will bring a shift towards a more southerly surface flow tomorrow as a low-amplitude upper-level ridge moves over the Midwest.
1051 AM CST Fri Dec 25 2020 The current weather pattern across the CONUS is defined by a deep 500 mb low centered over the Ohio Valley with an accompanying highly amplified mid to upper level trough across much of the center and eastern CONUS. The warming trend continues into Saturday as a warm front lifts northward through the region. High temperatures for the I-70 corridor and south will be around 50 to even the mid 50s with cooler high temperatures as you travel northward toward the Iowa border, where highs will only reach the low 40s north of the warm front.
1008 AM MST Fri Dec 25 2020 25/00Z H500 map continues to show an amplified pattern in place with a deep trough moving through E. ridging dominating the Rockies. The ridge will slowly move into the High Plains today as the upstream system makes its way inland. Chances of mixing this warmer air down to valley areas will be a difficult task and the large spread of guidance temperatures is not a good exercise in confidence building. Overall stayed near previous forecast if just a bit cooler in some areas with the cold pools in the larger basins expected to stay anchored in place.
305 PM EST Fri Dec 25 2020 Arctic high pressure will build across the region through the weekend. The anomalously deep closed low/upper trough will traverse the area through the evening.
219 PM CST Fri Dec 25 2020 Merry Christmas and Happy Holidays from all of us here at the National Weather Service in Tulsa! The trough that brought us much cooler weather than normal continues to slide eastward across the eastern part of the US.
1011 AM EST Fri Dec 25 2020 The Christmas special continues as very cold air and light snow will continue through much of the day before building high pressure leads a drier and slightly warmer weekend. Regional radars show snow showers continuuing across much of the area now in the deep cold, post-frontal environment that's left in wake of yesterday's cold front. Models continue to indicate that most additional snowfall today will occur near or north of the I-80 corridor (from Lake Erie) and in the Allegheny Mountains (from Upslope), though another inch can't be ruled out for Pittsburgh and elsewhere in the lower elevations. Areas of mainly light snow should taper off overnight as the upper low weakens into a trough and exits the area. Mainly dry weather is expected Saturday as weak sfc ridging builds under cold NW flow aloft.
Although the sky will be clear tonight, a slightly stronger wind and westerly component will keep temperatures warmer. Variability in temperature readings should be on the higher side tonight too. The westerly surface wind component should result in afternoon highs on the warmer side of guidance.
This will be especially so on Saturday as the upper ridge now over the northern/central Rockies dampens as it moves eastward over the northern/central Plains. Westerly component downslope flow off the high Plains late today will advect over the eastern half of Kansas thru Saturday.
As high pressure regains control, winds should begin to subside and clouds begin to diminish later this evening with VFR prevailing.
249 PM CST Fri Dec 25 2020 Flurries and light snow continue, mainly in the north and east as another lobe of the upper trough moves through the mid state. Temps will warm up a bit Saturday as ridging tries to build in overhead behind the trough, and southerly/southwesterly winds at the surface will help warm the area up.
1026 AM CST Fri Dec 25 2020 Little change expected in the arctic air mass spreading into the mid TN Valley from the west, aided by a deep upper low/trough lifting NE across the mid/srn Atlantic states.
High pressure centered over the Gulf Coast will then begin building into the area tonight with winds shifting back towards the southwest at around 5-10 mph. Highs for the day will be in the lower to mid 40s, much closer to climatological norms.
The next Pacific origin cold front enters our western counties during the day, spreading a chance of snow showers over the Sierra Madre Range in the afternoon. Low level gradients look sufficient for high winds over our wind prone locations, where the High Wind Warning continues through late morning.