Aikyam-Lab/Synoptic-Bench huggingface dataset:
834 PM MST Tue Dec 29 2020 Latest satellite trends showing abundant high clouds obscuring the low stratus cloud deck at the surface. Mid to high clouds will increase overnight with snow showers developing over the higher terrain after 12z/Wed.
As warm advection continues ahead of the trough, temperatures should be above freezing by afternoon even across the far north. The trough pushes east today with the back edge of the rain or mixed precip exiting the eastern zones this afternoon. Colder air filters in for tonight with some refreezing of wet road surfaces possible along with lake effect clouds/flurries along Lake Michigan this evening.
While a few showers cannot be ruled out overnight, chcs will remain low until Wednesday morning when moisture and lift increase with the approach of a cold front acrs TX. Warm and moist gulf air is moving north across the area this afternoon ahead of low pressure taking shape over the Central Plains. An upper trough that is currently digging into northern Mexico and the SW sections of the US will pinch off and upper low during Wednesday. Lift will increase through Wednesday ahead of the digging trough and newly formed upper low increasing rain chances locally.
150 AM MST Wed Dec 30 2020 Expect increasing high clouds today as high pressure aloft builds into the region. Surface pressure gradients will tighten in the foothills in response to lee side troughing.
The much anticipated cold front was entering Western Osage co as of 03z this evening. the cold front will continue to make its way southeastward across much of Eastern Oklahoma and Northwest Arkansas with a location near/just southeast of a line from MLC to FYV by 12z Wednesday. Surface temps by sunrise Wednesday look to be in the mid 30s near the Oklahoma Kansas border to the low 50s remaining ahead of the front near the Red River. have added minor adjustments to hourly temp/dewpoint/wind/pop grids based on the movement of the cold front and have also increased minor wintry precip potential across Northeast Oklahoma Wednesday morning.
937 PM CST Tue Dec 29 2020 Snowfall and freezing precipitation has ended across the area. As drier air pushes in, we are losing saturation aloft, we have seen freezing drizzle gradually develop from west to east across the area. Overnight lows may dip into the low teens, particularly in northwestern portions of the area where skies fully clear out. Even still, the cold airmass will make it tough for highs to reach freezing in portions of the area.
1038 PM CST Tue Dec 29 2020 (This evening through Wednesday) Isentropic ascent-driven showers continue across northwest Oklahoma, and this is where the highest rainfall amounts have been so far (over 0.
200 AM MST Wed Dec 30 2020 Expect increasing high clouds today as high pressure aloft builds into the region. Surface pressure gradients will tighten in the foothills in response to lee side troughing.
Forecast is on track this evening with a potent 140-160 kt upper jet across the Great Lakes and an associated surface cyclone across the upper Mississippi Valley.
221 AM CST Wed Dec 30 2020 Bulk of accumulating snow has pushed out of the area ahead of a mid- level trough of low pressure pushing through the region. Still some light snow ongoing and areas of freezing drizzle. Looks like this will persist into the morning hours until the trough pushes east of the region. 8 inches at the office here on top the La Crosse Ridge). As stated, expect the precipitation to push east of the area this morning as lift ends with passage of that mid-level trough. Otherwise, stratus cloud cover will linger across the area behind the trough in broad cyclonic flow.
323 AM EST Wed Dec 30 2020 A mix of sleet and freezing rain will develop overnight. Any freezing rain will changeover to rain from west to east late tonight into Wednesday morning.
Updated for 06Z Aviation Forecast Discussion and end of the The light freezing drizzle has mostly ended, so went ahead and canceled the advisory a little early. This is robbing the dendritic growth zone from ice development and has lead to the transition to sleet, freezing rain, and freezing drizzle. Winds out of the WNW at 8-18 mph will leave apparent temps even cooler.
High pressure will expand east across the Great Basin through Wednesday.
Snowfall and freezing precipitation has ended across the area. As drier air pushes in, we are losing saturation aloft, we have seen freezing drizzle gradually develop from west to east across the area. Overnight lows may dip into the low teens, particularly in northwestern portions of the area where skies fully clear out. Even still, the cold airmass will make it tough for highs to reach freezing in portions of the area.
1117 PM CST Tue Dec 29 2020 Message of the Day: Wintry mix of snow, sleet, and freezing rain will continue this afternoon into the overnight hours in far northwest MO and along the MO/IA border. A low pressure system is approaching our area this afternoon, pushing a warm front north with it. This is because the freezing line will struggle to reach far northwest MO and the MO/IA border tonight.
Leading edge of showers/cold front has moved into northeast OK and will push into northwest AR and southeast OK toward 10Z. The much anticipated cold front was entering Western Osage co as of 03z this evening. the cold front will continue to make its way southeastward across much of Eastern Oklahoma and Northwest Arkansas with a location near/just southeast of a line from MLC to FYV by 12z Wednesday. Surface temps by sunrise Wednesday look to be in the mid 30s near the Oklahoma Kansas border to the low 50s remaining ahead of the front near the Red River. have added minor adjustments to hourly temp/dewpoint/wind/pop grids based on the movement of the cold front and have also increased minor wintry precip potential across Northeast Oklahoma Wednesday morning.
Currently, a cold front extends from western Missouri through northeast Oklahoma and into north central Texas. This cold front will continue to move east today and will be just west of the Mid-South by this evening. The cold front through much of the region tonight before stalling out across north Mississippi.
249 AM EST Wed Dec 30 2020 Models are still very consistent with a trough digging into Texas/Mexico, then lifting out and developing an occlusion over Northeast Texas.
Much ballyhooed cold front was south of Tucumcari-Amarillo and is set to arrive at HOB by 08Z and MAF by 09Z.
1259 AM EST Wed Dec 30 2020 A cold front will bring rain showers to the area late this afternoon and into the overnight hours. Once the warm front passes late tonight, temperatures will stabilize. The weak cold front will begin to cross the region late this evening and exit to the south shortly before dawn.
In addition to the light snow and flurries, gusty northwest winds will usher in a cooler air mass but temperatures are still expected to rise into the mid 20s which is near normal.
Temperatures won't make it much past the lower to mid 20s, and may even slide backwards over their current values.
Deep moisture continues to flow out of the gulf ahead of a cold front and this will provide a few isolated light showers for some areas through tonight.
Patternwise, an upper trough in the eastern Dakotas was translating toward the Upper Midwest region early this morning. SREF probs are on the low end for fog development and high resolution models are not indicating much potential for development and have not included in the forecast.
Meanwhile, local radars are detecting patches of light rain and sprinkles near the Lower and Middle Keys and the adjacent coastal waters. The expansive region of high pressure covering the Eastern United States equatorward through the Sunshine State and the adjacent Atlantic and Gulf waters today, will retreat into the western Atlantic Ocean with a lengthy ridge axis reaching across the Florida Peninsula by the end of this week. Meanwhile, a low pressure will gradually develop along the eastern Texas coast, resulting in a tight pressure gradient along with a veering east to southeast trajectory underneath a pesky inversion based near 070.
535 AM CST Wed Dec 30 2020 Widespread rain is falling across the CWA along and behind a cold front as a mid level trough moves through the region. For tonight into Thursday morning, models have trended cooler aloft and drier with a quicker end to precipitation. Note the shift away from freezing rain in the previous forecast given the colder trend aloft. Precipitation type forecast is challenging given model variance in the elevated warm layer, so can't completely rule out some light freezing rain but even so amounts would be very light. No significant impacts are anticipated at this time given light amounts and temperatures near freezing in the area with precip.
A warm front has brought a wintry mix of snow, sleet, and light freezing rain across the Lower Columbia Basin and the Blue Mtn Foothills at this time. A cold front will arrive to the Cascades this evening, and snow will decrease in intensity after the frontal passage. A northwest flow behind the cold front will bring moderate to heavy snow to the Blue Mountains on Thursday. An upper level ridge building over WA/OR on Thursday will bring drier conditions to most of the forecast area by the afternoon with the exception of the Blue Mountains and foothills, Wallowa County, and the WA/OR Cascades. Although there will be increasing subsidence during this time, overcast skies will keep fog and freezing fog from developing.
426 AM CST Wed Dec 30 2020 Widespread rain is falling across the CWA along and behind a cold front as a mid level trough moves through the region. For tonight into Thursday morning, models have trended cooler aloft and drier with a quicker end to precipitation. Note the shift away from freezing rain in the previous forecast given the colder trend aloft. Precipitation type forecast is challenging given model variance in the elevated warm layer, so can't completely rule out some light freezing rain but even so amounts would be very light. No significant impacts are anticipated at this time given light amounts and temperatures near freezing in the area with precip.
629 AM EST Wed Dec 30 2020 Freezing rain will change over to rain from south to north early this morning, although secondary roads near the Michigan line may stay slippery into late morning. Temperatures will warm into the 40s this afternoon before a cold front moves across the area. Northern stream upper trof along ND/MN border will slide eastward toward Lake Superior early this morning. HREF mean precip type still indicating ~4hr window for freezing rain over northern portion of the CWA this morning before becoming all rain 11- 13Z.
Stratus was slow to scatter out across eastern KS behind the front, resulting in morning low temperatures staying a bit "warmer" in the upper 20s/low 30s versus dropping into the low/mid 20s by sunrise across north central and central KS where clearing had occurred. A split-flow was in place this morning, with a mid-level trough advancing toward the Great Lakes region and a cut-off low sitting over northern Mexico near the Arizona/New Mexico borders.
A southerly pressure gradient will cause a transition to mixed precipitation along the Highway 12 corridor by mid- morning as air temperatures warm above freezing, but ground temperatures remain below freezing. Snowfall rates will increase Wednesday afternoon and evening along the Idaho and Montana border for elevations above 2,500 feet as the upper level trough rounds into eastern Washington. A longwave trough extending southeastward from the Gulf of Alaska through the Pacific Northwest will direct a train of Pacific storm systems into the western U.
Otherwise mid to high clouds will spread across the region from the west as upper ridge builds into the Northern Rockies.
250 AM MST Wed Dec 30 2020 Weak ridging continues across the state today, but will be disturbed by the approaching trough coming ashore across the Pacific Northwest. H7 winds remain gusty, but from the northwest, so gustiest surface winds will be limited mainly to Sweetwater County, along with the higher Absarokas this afternoon. Most of the trough will drop southward into the Four Corners region, but some midlevel support will sweep through tonight into tomorrow. A quiet start to the period as a upper-level ridging settles into the area for Thursday night.
401 AM EST Wed Dec 30 2020 A cold front will bring rain showers to the area late this afternoon and into the overnight hours. Showers will slowly overspread the region from northwest to southeast this afternoon ahead of a weak cold front. The weak cold front will begin to cross the region late this evening and exit to the south shortly before dawn. High pressure will continue to push the surface boundary south on Thursday afternoon, resulting in dry conditions.
820 AM EST Wed Dec 30 2020 A cold front will bring rain showers to the area late this afternoon and into the overnight hours. Light to moderate widespread rain forced by decaying frontogenesis will move in this afternoon as a cold front approaches from the northwest. The weak cold front will begin to cross the region late this evening and exit to the south shortly before dawn. High pressure will continue to push the surface boundary south on Thursday afternoon, resulting in dry conditions.
Currently, a cold front extends from western Missouri through northeast Oklahoma and into north central Texas. This cold front will continue to move east today and will be just west of the Mid-South by this evening. The cold front through much of the region tonight before stalling out across north Mississippi. On Thursday, low pressure will develop along the front over southeast Texas and will track slowly north. Temperatures will vary quite a bit depending on which side on the front one is at with highs from the lower 40s to mid 60s.
512 AM CST Wed Dec 30 2020 Northwest flow aloft takes hold across the region today as an upper low digs into northern Mexico by Thursday morning. Meanwhile another upper trough moves onto the west coast. At the surface, high pressure will track from western KS this morning to southeast Nebraska by this evening. The upper low across Mexico will begin to track northeast into TX Thursday, still well south of our area. High temperatures will rise a few more degrees Thursday as warmer air aloft (H85 temps 2-3C) and southwest low-level flow advect warmer air into the area.
/issued 249 AM EST Wed Dec 30 2020/ Models are still very consistent with a trough digging into Texas/Mexico, then lifting out and developing an occlusion over Northeast Texas.
The upper low continues to rotate through the region, and will slowly pull eastward into the Great Lakes today. There is still quite a bit of light snow on the backside of the low pressure system that is currently centered over northern MN. Winds will pick up from the south to southwest tonight as a weak trough begins to develop over the western Plains, which should keep temps mostly above zero even with fresh snow cover.
Corresponding winds out in the Arlington zone gusting in the low 40s at Arlington and County Road 402 sensors.
917 AM EST Wed Dec 30 2020 Strong high pressure sits over the mid-Atlantic states and ridges southwest over Florida and into the Gulf of Mexico. Latest visible satellite imagery and surface observation continue to show a SCT/BKN SC cloud deck around 3-5 kft from Tampa Bay northward and over the cooler waters of the gulf. High pressure over the mid-Atlantic states ridging over Florida and into the gulf will keep east-southeast winds around 10-15 knots over the waters for today and tonight.
Overnight lows in the low to mid 60s, except along the Space and Treasure Coast, where onshore flow will keep temperatures in the upper 60s.
400 AM CST Wed Dec 30 2020 Northwest flow aloft takes hold across the region today as an upper low digs into northern Mexico by Thursday morning. Meanwhile another upper trough moves onto the west coast. At the surface, high pressure will track from western KS this morning to southeast Nebraska by this evening. The upper low across Mexico will begin to track northeast into TX Thursday, still well south of our area. High temperatures will rise a few more degrees Thursday as warmer air aloft (H85 temps 2-3C) and southwest low-level flow advect warmer air into the area.
342 AM MST Wed Dec 30 2020 The upper level trough axis is pushing through the eastern portions of the state with increasing subsidence over the region. Cross barrier flow will increase slightly with winds gusting upwards of 30 mph over the higher peaks by the afternoon. 700 mb temperatures will be on the rise with values between 5 and 6C warmer than yesterday. This will help to bring highs into the lower 40s over the I-25 corridor with cooler temps further east and north where there is slightly more snow cover. Lows overnight will be in the teens and 20s on the plains and single digits in the high country with below zero some the high mountain valleys.
415 AM MST Wed Dec 30 2020 Weak ridging continues across the state today, but will be disturbed by the approaching trough coming ashore across the Pacific Northwest. H7 winds remain gusty, but from the northwest, so gustiest surface winds will be limited mainly to Sweetwater County, along with the higher Absarokas this afternoon. Most of the trough will drop southward into the Four Corners region, but some midlevel support will sweep through tonight into tomorrow. A quiet start to the period as a upper-level ridging settles into the area for Thursday night.
Have adjusted lows for this morning to reflect the lower than anticipated temperatures in the aforementioned areas. The aftermath of this battle is expected to end with highs reaching the upper 30s to lower 40s across the plains and upper 20s to lower 30s in the high valleys. Clear skies are expected to continue as slight ridging transitions the flow aloft to more westerly.
556 AM EST Wed Dec 30 2020 Seasonably cool and fair conditions today, will transition to increasingly mild and wet weather Thursday into the weekend, as a series of low pressure systems migrate along a warm front.
Southerly winds of 10-20 mph with gusts in the low 30s are ongoing.
The upper level trough axis is pushing through the eastern portions of the state with increasing subsidence over the region. Cross barrier flow will increase slightly with winds gusting upwards of 30 mph over the higher peaks by the afternoon. 700 mb temperatures will be on the rise with values between 5 and 6C warmer than yesterday. This will help to bring highs into the lower 40s over the I-25 corridor with cooler temps further east and north where there is slightly more snow cover. Lows overnight will be in the teens and 20s on the plains and single digits in the high country with below zero some the high mountain valleys.
CD Chattanooga Airport, TN 61 46 60 55 70 / 0 20 50 90 90 Knoxville McGhee Tyson Airport, TN 61 44 60 51 68 / 0 20 40 90 90 Oak Ridge, TN 60 44 58 50 67 / 0 30 50 90 80 Tri Cities Airport, TN 60 39 59 48 64 / 0 20 30 80 90 TN.
BW Chattanooga Airport, TN 61 46 60 55 70 / 0 20 50 90 90 Knoxville McGhee Tyson Airport, TN 61 44 60 51 68 / 0 20 40 90 90 Oak Ridge, TN 60 44 58 50 67 / 0 30 50 90 80 Tri Cities Airport, TN 60 39 59 48 64 / 0 20 30 80 90 TN.
251 PM CST Wed Dec 30 2020 (Issued 251 PM CST Wed Dec 30 2020) Tonight through Thursday night: Westerly winds will gradually become lighter tonight into Thursday as low pressure continues to shift to the northeast and high pressure moves overhead. Expect some sunshine tomorrow as clouds clear under the ridge.
220 PM CST Wed Dec 30 2020 Upper level low over the Great Lakes continues to push eastward with northwest flow in place over the Northern Plains. As this ridge continues to move eastward, low level stratus was eroding slightly with the back edge just about to Bismarck by mid afternoon. Thursday highs expected to range from the low 40s southwest to the mid 20s northeast.
Northern track = likely more snow, but also some threat for freezing pcpn.
Tonight: There will be partly to mostly cloudy skies with light northwest winds, as high pressure settles over the cwa. Thursday: The high pressure moves to our east allowing for light south winds but forecast soundings indicate minimal mixing.
140 PM EST Wed Dec 30 2020 A cold front will bring rain to the area this afternoon that will change to snow Thursday morning.
The next short term concerns will be assessing travel hazards overnight/Thursday morning with possible refreezing on roads surfaces tonight. As warm advection continues ahead of the trough, temperatures should be above freezing by afternoon even across the far north. The trough pushes east today with the back edge of the rain or mixed precip exiting the eastern zones this afternoon. Colder air filters in for tonight with some refreezing of wet road surfaces possible along with lake effect clouds/flurries along Lake Michigan this evening.
Speeds are generally in the 15-25 mph range with gusts in the lower to mid 30s.
LIFR ceilings are expected with wrap around moisture as the low moves over the area but mainly effecting the central and northern flying areas.
This area saw the greatest snowfall and have adjusted cooler to account for the snow packed ground that has kept temperatures cooler than expected through mid-morning. Northwest flow aloft takes hold across the region today as an upper low digs into northern Mexico by Thursday morning. Meanwhile another upper trough moves onto the west coast. At the surface, high pressure will track from western KS this morning to southeast Nebraska by this evening. The upper low across Mexico will begin to track northeast into TX Thursday, still well south of our area. High temperatures will rise a few more degrees Thursday as warmer air aloft (H85 temps 2-3C) and southwest low-level flow advect warmer air into the area.
Precipitation chances begin to increase tonight into tomorrow as a deep low pressure system over northern Mexico begins to approach the region. With the strong onshore flow and building seas, we will continue the High Rip Current Risk and High Surf Advisories. High temperatures tomorrow climb into the low to mid 70s.
211 PM EST Wed Dec 30 2020 Upper air pattern consists of a 500 mb trough over the upper Great Lakes this morning which will head east and be exiting the area by this evening. trough will kick out the closed low over northern Mexico to the northeast into TX on Thu. Thursday night high pressure settles in over the Lower Great Lakes, resulting in an uneventful partly cloudy to clear evening for the region.
Northern stream upper trof along ND/MN border will slide eastward toward Lake Superior early this morning. HREF mean precip type still indicating ~4hr window for freezing rain over northern portion of the CWA this morning before becoming all rain 11- 13Z.
Temperatures in the lower 20s Thursday morning will be more than sufficient to develop ice on wet untreated surfaces. Currently, the most plausible scenario for New Years Day is predominantly freezing rain south of I-96 where accumulations might reach or exceed a quarter of an inch in spots around I-94. Forecast reasoning: Powerful upper low off the Pacific Northwest will serve as an upstream kicker for the cutoff low currently over northwest Mexico. There is some indication that models are not initializing this feature well, perhaps due to a combination of the low's highly anomalous nature and sub-optimal sampling of the atmosphere over NW Mexico (due to a relative lack of aircraft measurements and POES swaths).
The likelihood of the forecast area being affected by an ejecting southern stream cyclone on New Year's Day has diminished considerably since yesterday. Any light freezing drizzle should change to snow flurries as temperatures fall. A departing anticyclone will still be ridging back into the area, resulting in light winds and very likely calm conditions at times. The main unknown is the amount/extend of Ci/Cs streaming northward off the approaching southern stream cyclone.