Aikyam-Lab/Synoptic-Bench huggingface dataset:
1146 AM EST Mon Jan 25 2021 A wintry mix is expected through Tuesday with crossing low pressure, with impactful ice accumulations expected across northern portions of the forecast area and in the eastern ridges. Radar mosaic depicts areas of light precipitation returns across southern portions of the forecast area as moisture increases ahead of a digging trough across the central Plains. With sfc temperature still below freezing region-wide, effects of warm advection will support a wintry mix event as the boundary layer gradually warms. This means an onset of light, wintry mix in the form of snow / sleet / freezing rain from south to north as precipitation advances northward. More significant impacts are expected across the eastern ridges, where a Winter Storm Warning remains in effect to address forecast ice accumulations between 0.
Highs should range from the lower 60s to lower 70s across the region this afternoon. This system will ooze through tonight and allow temperatures to fall into the low to mid 30s north of I-20 with lower 40s to the south.
1143 AM CST Mon Jan 25 2021 Surface temperatures remain around or slightly above freezing in northeast MO and west-central IL, which does not bode well for ice accretion. This would keep a mainly light rain/freezing rain scenario, with ice accumulations up to two tenths of an inch possible for the Winter Weather Advisory area, though some minor snowfall accumulations are still possible, especially during the morning hours today. Dry conditions expected by Tuesday afternoon with highs in the low 30s to mid 40s.
SHORT TERM (Tonight through Tuesday Night): A cold front is moving through Deep South Texas this afternoon. Winds overnight will be northerly to northeasterly bringing cooler air to the region. Low temperatures will drop into the 50s over the northern ranchlands and middle 60s over the lower RGV. Tuesday, high pressure will move off the coast of Mexico and turn the winds to the east. Tuesday night another cold front will move into the region, but will again move through dry.
The cold front has moved to the coast and in its wake winds have become northwesterly across South Central Texas. High pressure will move across Central Texas and winds will shift from northwesterly to easterly to southeasterly Tuesday. Tuesday night another Pacific cold front will move into the region.
1127 AM CST Mon Jan 25 2021 Northwest winds will switch around to the northeast this evening behind a cold front.
257 PM EST Mon Jan 25 2021 While weak high pressure will provide fair dry weather through the first half of tonight.
Spotter reported 2 inches of snow in Grace overnight, so the low-topped cloudiness has been missing the radar, but the snow has continued.
The upper low that brought SHRA/TSRA to parts of the area last night has moved out and the assocd Pacific front has moved thru leaving the above referenced gusty westerly winds in its wake. As winds subside early this evening, making for a cold Tue AM, the next upper low will rapidly move e and pass n of the area late in the day Tue. Cool and dry Wed/Thur before warming Fri with the development of the low-level thermal ridge. Quiescent wx conditions will follow Sun/Mon as broad mid- level ridging promotes temps slightly above normal.
259 PM EST Mon Jan 25 2021 Low pressure will pass through the area on Tuesday.
The warm frontal boundary associated with the system to our west will continue to move north through the area today. Strong dynamics are in place with low-level convergence expected late this evening associated with the approaching cold front. Some improvement may occur this afternoon as rain becomes less widespread, but additional scattered showers, and potentially a few thunderstorms, are expected late in the period along a cold front. JB Chattanooga Airport, TN 62 59 68 46 60 / 60 80 20 20 50 Knoxville McGhee Tyson Airport, TN 60 58 66 44 58 / 90 80 30 10 60 Oak Ridge, TN 57 55 66 41 57 / 100 80 20 10 50 Tri Cities Airport, TN 53 50 65 39 57 / 100 70 40 10 60 TN.
235 PM CST Mon Jan 25 2021 Chances for lingering very light snow/freezing drizzle look to remain across central Kansas into the evening with shallow isentropic upglide as the colder air oozes south across the area. Next upper trof now moving through SoCal will move out across the central/southern Rockies on Tuesday before moving over the central/southern Plains.
Cloudy skies and above average temperatures will persist through tonight into tomorrow as humid southerly flow moves across the region, ahead of the advancing cold front moving in towards the forecast area from out of the north-northwest. Overnight low temperatures will be in the lower 60s and upper 50s.
Temperatures mainly in the lower to mid 70s & lower 70s dewpoints ahead of the front, with slightly cooler & much drier air behind the front.
Weak isentropic ascent in the low level warm advection pattern will allow for patchy light rain this afternoon. Deep layer moisture and ascent will gradually spread eastward across the Mississippi Valley and into our southeast MS and interior southwest AL counties late this afternoon well in advance of a cold front that will be crossing the Mississippi Valley region. The low pressure system will continue to lift toward the Mid Mississippi and Ohio Valley regions through late tonight but the attendant surface cold front slows down and may only be approaching the far northwest part of our CWA in interior southeast MS and southwest AL by sunrise Tuesday. POPs trend up to 60-80% southeast of a Wiggins, MS to Greenville, AL line by Tuesday afternoon, with the highest chances aligned near the coast.
Currently, Arctic high pressure is situated from central Saskatchewan into southern Manitoba with low pressure from the central Rockies eastward into the central Plains. Although the low level northeast flow will help to scour out the lowest levels of the atmosphere, flow remains south to southeast above this and there remains a continuous surge of weak warm advection over the Arctic airmass. Lows tonight will range from the teens below zero north to the lower single digits above zero southwest. On Tuesday it looks like maybe the south central and southeast could see some clearing of the lower clouds, although there will probably be enough mid and high clouds that we won't see much of the sun. There are indications that the lower clouds may linger through the day for areas farther north and west.
1235 PM EST Mon Jan 25 2021 Low pressure will remain over the Maritimes today. High pressure will build into the area Tuesday.
After the frontal boundary briefly exits the region to the west, it will begin to reverse its course as a warm front.
1215 PM CST Mon Jan 25 2021 There are two main forces in play today into Tuesday: the high pressure over the Canadian Prairies and the the winter storm moving across the Midwest. Minnesota and west central Wisconsin will be caught between these two as the snow system tracks to our south and the high remains to our north.
There is some speed and directional shear in the low-levels, but at this time helicities aren't excessive. A warm front that moved northward through Middle Tennessee overnight has become quasi-stationary near the TN/KY border, so most of Middle Tennessee is now in the warm, moist sector. A pre-frontal trough will swing through the mid state later this afternoon and evening, and this will provide some focus for the expected storms.
With the low clouds and precip, made sense to drop temperatures a few degrees everywhere, too. Patchy fog may occur over terrain areas given the low ceilings that are out there. Ensemble guidance points to a trough digging into the Pacific coast, a trough over the NE U. , and a ridge in between, including across the Northern High Plains for the second half of the week. This will lead to recoveries in temperatures with daytime highs getting back above freezing for many areas, as well as dry conditions for the most part. As the ridge translates east and flattens toward the weekend, a more unsettled pattern may unfold, but, at larger time scales confidence is reduced.
The 12z sounding at KEY showed a 4 degree Celsius temperature inversion based at around 900 mb in response to an expansive ridge extending over the western Atlantic and the Florida Peninsula.
(This evening through Tuesday) Temperatures this afternoon are a few degrees cooler than 24 hours ago, due to the cold front that moved through last night. Early Tuesday morning, a weak cold front will move down into the Big Country and likely stall over that region. A similarly strong 850 mb thermal ridge and warm southwest to west winds will result in highs Tuesday in the mid 60s to low 70s, except in the Big Country where there will be an east to northeast component to the winds behind the stalled weak cold front, bringing a little cooler air to that region (upper 50s/low 60s).
229 PM MST Mon Jan 25 2021 Latest analysis shows an upper low over SE Nebraska with a ridge building over Montana and Alberta. At the surface, low pressure is centered over southwestern Missouri with high pressure dropping southward from Saskatchewan into North Dakota. Bands of snow rotating northward around the low pressure system will bring some accumlating snow into south central and southwestern South Dakota with possibly up to an inch of accumulation over parts of south central South Dakota. There is also a chance of a little light freezing drizzle as the fog redevelops early this evening, with chances decreasing as the evening progresses.
Moisture with that trough should hang around for most of the night and even retrograde back a bit to the west, so expecting continued light snows east of Fort Morgan to Limon overnight. Cloud cover should be on the increase this afternoon as moisture advects northward ahead of the approaching trough axis. A couple inches of snow is still possible over the higher terrain, with an inch or less for the lower elevations. Light snow will continue Tuesday evening before subsidence and dry air move in to replace the upper low exiting to the east.
Storms will continue to form in the warm sector over the next couple of hours before the cold front sweeps through. Tuesday will be dry and mild as Pacific high pressure builds into the region. The weather pattern will quickly turn cold tomorrow night as a secondary cold front descends from the northwest. Simultaneously, an unusually cold trough will lift through the region in the afternoon.
As of 21Z, the CWA is situated between an strong storm system to our south, and a high pressure off to our north. With the high pressure filtering in colder air, low temperatures tonight could drop into the single digits on either side of zero. The high pressure will slowly nudge southeast into northern Minnesota on Tuesday, bringing below normal temperatures with highs reaching the upper single digits, to the lower 20s.
No other changes at this time, but if more clearing occurs, may have to revisit the lows for tonight. A couple of low pressure systems will move across the central High Plains region from this evening through late Tuesday night. Snow associated with a low pressure area that moved through the area this morning has diminished substantially this afternoon, although up to an additional one to one and one half inches of snow is still possible through the remainder of this afternoon across that area. Overnight lows tonight will be around 10 degrees while overnight lows Tuesday night will be in the low single digits above zero. A broad upper ridge begins developing across the central U.
Snowfall looks to increase across southeast Utah and southwest Colorado this evening, as a closed mid level low pressure system associated with a larger trough across the west, moves into the Las Vegas area. By Tuesday afternoon, the low opens up and forcing begins to wane as the trough finally pushes east across the area. Some lingering light snow will occur over the divide Tuesday evening, but drier air will begin to filter in from the northwest as a ridge of high pressure moves into the Great Basin.
A couple of low pressure systems will move across the central High Plains region from this evening through late Tuesday night. Snow associated with a low pressure area that moved through the area this morning has diminished substantially this afternoon, although up to an additional one to one and one half inches of snow is still possible through the remainder of this afternoon across that area. Overnight lows tonight will be around 10 degrees while overnight lows Tuesday night will be in the low single digits above zero. A broad upper ridge begins developing across the central U.
523 PM CST Mon Jan 25 2021 Still looks like we have some flash flooding potential late this afternoon in the current watch area that covers much of western KY as a warm frontal boundary down close to the TN border tries to nudge a bit farther north into far southern KY. Thereafter, expect a break in rain chances through Tuesday and most of Tuesday night as very weak ridging within the broad swly flow aloft shifts ne across the region. Currently, we have max temps fcst mainly in the lower 40s far north to the mid 50s far southern Pennyrile of wrn KY. Low temps Tuesday night are expected to fall to near or below freezing over most locations.
Dense sea fog is advecting into the coastal areas ahead of a cold front. Temperatures mainly in the lower to mid 70s & lower 70s dewpoints ahead of the front, with slightly cooler & much drier air behind the front.
559 PM CST Mon Jan 25 2021 (This evening through Tuesday) Temperatures this afternoon are a few degrees cooler than 24 hours ago, due to the cold front that moved through last night. Early Tuesday morning, a weak cold front will move down into the Big Country and likely stall over that region. A similarly strong 850 mb thermal ridge and warm southwest to west winds will result in highs Tuesday in the mid 60s to low 70s, except in the Big Country where there will be an east to northeast component to the winds behind the stalled weak cold front, bringing a little cooler air to that region (upper 50s/low 60s).
322 PM CST Mon Jan 25 2021 Still looks like we have some flash flooding potential late this afternoon in the current watch area that covers much of western KY as a warm frontal boundary down close to the TN border tries to nudge a bit farther north into far southern KY. Thereafter, expect a break in rain chances through Tuesday and most of Tuesday night as very weak ridging within the broad swly flow aloft shifts ne across the region. Currently, we have max temps fcst mainly in the lower 40s far north to the mid 50s far southern Pennyrile of wrn KY. Low temps Tuesday night are expected to fall to near or below freezing over most locations.
A backdoor cold front will move slowly to the southwest past KCDS early in the period, KPVW toward midnight, and possibly stalling before reaching KLBB with relatively light northeast winds behind it.
307 PM CST Mon Jan 25 2021 As of 21Z, the CWA is situated between an strong storm system to our south, and a high pressure off to our north. With the high pressure filtering in colder air, low temperatures tonight could drop into the single digits on either side of zero. The high pressure will slowly nudge southeast into northern Minnesota on Tuesday, bringing below normal temperatures with highs reaching the upper single digits, to the lower 20s.
735 PM MST Mon Jan 25 2021 Updated forecast for tonight to extend the coverage of fog for the high valleys west of the Laramie Range. Cold front analyzed on surface analysis from Cody to Rawlins to Laramie.
Surface data at 2 PM revealed a stubborn cold front stretching from Zapata, TX northeast to near Alice and up to Port Lavaca. Although dry surface ridging with ENE surface winds prevails tomorrow, a thin layer of WAA will be present just a couple thousand feet above the surface complete with some stratus, particularly over the Coastal Plains. Stratus will expand expand over much of the region Tuesday night with perhaps some fog at times all in advance of a fast- moving cold front after midnight.
Updated to add dense fog to the forecast in the cooler airmass across portions of East Arkansas, Northwest Tennessee and the Missouri Bootheel. Storms will continue to form in the warm sector over the next couple of hours before the cold front sweeps through. Tuesday will be dry and mild as Pacific high pressure builds into the region. The weather pattern will quickly turn cold tomorrow night as a secondary cold front descends from the northwest. Simultaneously, an unusually cold trough will lift through the region in the afternoon.
A broad low pressure trough remains over much of the western US this morning, with the majority of the energy associated with this system directed southward into the Desert Southwest. Forecast models indicate that the upper level pattern will begin to shift by mid week, with southwest flow developing ahead of another low pressure system.
447 PM MST Mon Jan 25 2021 A couple of low pressure systems will move across the central High Plains region from this evening through late Tuesday night. Snow associated with a low pressure area that moved through the area this morning has diminished substantially this afternoon, although up to an additional one to one and one half inches of snow is still possible through the remainder of this afternoon across that area. Overnight lows tonight will be around 10 degrees while overnight lows Tuesday night will be in the low single digits above zero. A broad upper ridge begins developing across the central U.
Overnight into Tuesday, the elongated trough moves further inland, but with limited moisture. With this cloud deck and limited warming today, tonight's lows will be cool and below normal with the trough in place.
Snow is expected to continue along the Iowa/Missouri border, with drizzle and freezing drizzle possible farther south. -Cool temperatures expected on Tuesday with subfreezing highs in most locations on Tuesday.
These storms haven't been severe, but the warm front is now situated through McMinn, Meigs, Rhea, and Bledsoe county so these do appear to be tapping into some low level instability. Flight categories will decline in the coming hours as cold front and associated showers and thunderstorms move into the TN valley. Will see flight categories improve to VFR levels fairly rapidly after daybreak as cold front and associated convection exits TN and moves into NC. CD Chattanooga Airport, TN 56 67 46 58 31 / 80 20 10 40 10 Knoxville McGhee Tyson Airport, TN 46 65 42 55 30 / 80 30 10 40 50 Oak Ridge, TN 47 65 40 55 28 / 80 20 10 40 40 Tri Cities Airport, TN 49 62 38 54 27 / 90 40 10 50 80 TN.
Upper level trough remains over the region this afternoon. Expect low clouds and patchy freezing fog to linger in the the Columbia basin and valleys through the night. The next upper low will be approaching the Pacific northwest during the day. The upper low will remain centered offshore through Wed with a southwest flow aloft.
605 PM CST Mon Jan 25 2021 Chances for lingering very light snow/freezing drizzle look to remain across central Kansas into the evening with shallow isentropic upglide as the colder air oozes south across the area. Next upper trof now moving through SoCal will move out across the central/southern Rockies on Tuesday before moving over the central/southern Plains.
Widespread light snow should develop and continue through the afternoon as the synoptic trough moves through the region. Some of the coldest air of the season will settle in, and high temperatures due low clouds and the airmass itself will not exceed the low to mid 20s on Tuesday with light northeast winds becoming light northwest by the evening.
/Issued 153 PM CST Mon Jan 25 2021/ The cold front responsible for the overnight and morning showers and storms across eastern Oklahoma and western Arkansas is just about east of the area this afternoon.
MVFR cigs along with -SHRA and isold TSRA wl continue this evening along and ahead of a cold front that will be dropping into the area. After the frontal boundary briefly exits the region to the west, it will begin to reverse its course as a warm front.
440 PM MST Mon Jan 25 2021 Latest analysis shows an upper low over SE Nebraska with a ridge building over Montana and Alberta. At the surface, low pressure is centered over southwestern Missouri with high pressure dropping southward from Saskatchewan into North Dakota. Bands of snow rotating northward around the low pressure system will bring some accumulating snow into south central and southwestern South Dakota with possibly up to an inch of accumulation over parts of south central South Dakota. There is also a chance of a little light freezing drizzle as the fog redevelops early this evening, with chances decreasing as the evening progresses.
242 PM MST Mon Jan 25 2021 A couple of low pressure systems will move across the central High Plains region from this evening through late Tuesday night. Snow associated with a low pressure area that moved through the area this morning has diminished substantially this afternoon, although up to an additional one to one and one half inches of snow is still possible through the remainder of this afternoon across that area. Overnight lows tonight will be around 10 degrees while overnight lows Tuesday night will be in the low single digits above zero. A broad upper ridge begins developing across the central U.
642 PM MST Mon Jan 25 2021 Small chances for freezing precipitation have diminished enough that the chances have been removed from the forecast for the remainder of the evening. Latest analysis shows an upper low over SE Nebraska with a ridge building over Montana and Alberta. At the surface, low pressure is centered over southwestern Missouri with high pressure dropping southward from Saskatchewan into North Dakota. Bands of snow rotating northward around the low pressure system will bring some accumulating snow into south central and southwestern South Dakota with possibly up to an inch of accumulation over parts of south central South Dakota. There is also a chance of a little light freezing drizzle as the fog redevelops early this evening, with chances decreasing as the evening progresses.
407 PM CST Mon Jan 25 2021 Wow what a day its been so far! A potent mid level closed low has hit us head on with one of the the most impactful winter storms we've had since the Groundhog Day Blizzard of 2016. These are the areas that will see the highest snowfall totals and could still pick up an additional 3-5" by tomorrow morning.
250 AM EST Tue Jan 26 2021 High pressure surface and aloft will hold over west central and southwest Florida today with continued mild conditions across the area. An U/L disturbance will push across the Tennessee Valley late Wednesday with an associated cold front pushing southeast across the Florida peninsula late Wednesday and Wednesday night. U/L support will be lifting away from the region as the cold front pushes across the remainder of the forecast area which will cause shower activity to decrease in areal coverage as the band of showers pushes southeast Wednesday evening.
This is pushing warmer and more humid air across the Keys. Temperatures are slowly falling through the lower 70s with dew point temps jumping into the upper 60s to near 70. Stable conditions remain in place however due to deep layered ridging aligned over the Bahamas. Stable mostly clear skies continue due to this ridging. Short Term Update - The high near the Bahamas will slip further southeastwards and drag a ridge southwards across South Florida tonight. Deep layered ridging and lack luster flow will ensure another rain free night across the Keys. As a result, a related ridge axis will shift southwards into South Florida.
Very deep low pressure (500 mb height near 5320 m) was centered near Lake Havasu this evening. The very heavy snowfall rates should be backing off from west to east through this evening as the main moisture plume ahead of the approaching trough moves eastward. Very cold low temperatures are expected on Wednesday morning, in the single digits to below zero along the high terrain.