Aikyam-Lab/Synoptic-Bench huggingface dataset:
1000 PM MST Sun Jan 24 2021 With the region between the cutoff low off the California Coast and the trough crossing the northern US, stable weather has spread across the state.
1031 PM EST Sun Jan 24 2021 Currently - High pressure centered on the Carolina coast is producing light easterly breezes across the Keys this evening. Deep layered ridging, while not sharp, is robust and aligned over the northwestern Caribbean Sea and eastern Gulf of Mexico.
304 AM EST Mon Jan 25 2021 Low pressure will remain over the Maritimes today.
Heavier precip will arrive later tonight however as a warm front nears from the southwest. Lightning detection network has shown plenty of lightning strikes over the Arklamiss area this evening as elevated convection has blossomed over the warm front. Cigs decrease tonight as the warm front lifts north bringing an increase in moisture and rainfall late tonight and Monday morning with deteriorating vis within the moderate to heavy rain. JB Chattanooga Airport, TN 66 56 67 44 61 / 80 70 10 20 50 Knoxville McGhee Tyson Airport, TN 64 55 64 41 58 / 100 60 10 10 50 Oak Ridge, TN 59 53 64 39 57 / 100 70 10 10 40 Tri Cities Airport, TN 56 50 62 36 57 / 100 60 20 0 30.
Models were in good agreement with moving an upper level trough, located over New Mexico at 00z Monday, across southwest Kansas later this Monday morning. Ahead of this upper level trough there still is forecast decent moisture along with 850mb warm air advection along and improving 850mb to 700mb frontogenesis from just northeast of Dodge City to the Hays and Great Bend areas. Also noticing a ridge axis of 305 and 310 Theta-e extending westward into this area of frontogenesis from 12z to 18z Monday as the upper level trough lifts northeast across southwest Kansas. This does continue to favor a chance for an area of steady and heavier precipitation ahead of the upper level trough as it lifts northeast across western Kansas.
337 AM CST Mon Jan 25 2021 A sharp upper level low pressure trough was swinging east of the area just before daybreak, taking showers now well off to the east. Drying in the lower atmosphere has not yet occurred, but is expected just before daybreak on the Caprock as a Pacific Cold front passes to the east and then over the Rolling Plains near daybreak.
533 AM EST Mon Jan 25 2021 A wintry mix is expected today into Tuesday with crossing low pressure. Although freezing drizzle is not a concern attm as higher(colder) clouds continue to move in. some locations may see a light glaze of ice due to freezing fog or soft rime in areas without fog this morning. In coordination with surrounding offices a Winter Storm Warning was issued for the ridges where a prolonged period of freezing rain is expected to result in ice accumulations are forecast to exceed a quarter inch by Tuesday morning. A Winter Weather Advisory was issued for counties north of PGH where freezing rain is expected tonight and into tomorrow morning for northern locations as warm advection continues and sfc temperatures fall to/below freezing. More scattered precipitation will continue Tuesday as the associated upper trough passes.
Poorest visibilities will avoid the lower valleys (it will be stratus). JKL Our region remains under flat ridging, as a dynamic/cold trof dives along the Pacific coast. Some upstream obs are reporting light snow, and forecast soundings in our east suggest this is possible as the low level moisture deepens. so light freezing drizzle is not out of the question.
Frontal boundary was located along southwest periphery of the high from western MT into eastern WY into central NE. Synoptic lift will tickle southern SD with some light snow, coincident with weak 800-600mb frontogenesis along inverted trough feature. Might be some flurries or patchy freezing drizzle, but ice aloft will be fairly prevalent by Tuesday.
Early this morning, the synoptic flow was characterized by broad troughing over the western CONUS, and weak northwest flow over the forecast area due to upper troughing over central Canada. For today, expect a wide range in high temperatures, with highs from only a few degrees below zero in the Turtle Mountains, to the lower 20s in the southwest. Snow is expected to slowly taper off from west to east through the morning, although it has already been lingering in the northwest longer than expected, and with the low clouds would not be too surprised if there are scattered flurries through the day. On Tuesday, cyclonic flow aloft continues as a persistent upper low circulates above Manitoba and Ontario.
The associated cold front has moved southeast into the western Hill Country to near Del Rio. Milder temperatures are expected tonight with drier air and light winds with lows generally in the lower to mid 50s. Highs will be cooler on Tuesday over the coastal plains with expected cloud cover.
558 AM CST Mon Jan 25 2021 Cold front approaching the I-35 terminals this morning. The upper trough glides across the Panhandle over the next few hours and the associated cold front will make it's way into the area later this morning. The greatest forcing with this front will be to our north and northeast, closer to the base of the upper trough. With drier and cooler air in place, low temperatures dip into the 40s.
/issued 241 AM CST Mon Jan 25 2021/ The parade of upper troughs continues with the first trough swinging across the region early this morning. As this trough passes off to the NE the next upper trough will be working its way down the CA Coast. This next trough will briefly develop a closed low over Srn CA later today before moving over AZ tonight and then into NM Tuesday.
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.
A broad low pressure trough remains over much of the western US this morning, with the majority of the energy associated with this system trough 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.
A persistent SW flow aloft wl allow for a weak impulse to pass SE of AR late Tue, with some incrs in clouds expected, followed by some cooler air. Yet another upr trof wl apch the area later Tue ngt.
Combined with winds of about 5 to 10 mph, there could be hazardous wind chills around again, especially along and north of the highway 2 corridor.
959 AM EST Mon Jan 25 2021 While weak high pressure will provide fair dry weather through the first half of tonight.
339 AM 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.
High pressure holds steady through the mid portion of the week as warm air advection begins to warm temperatures. A negatively titled upper level trough begins to punch through the high by the end of the week into the weekend which will bring increasing chances for a weekend system that results from the enhanced forcing from this trough. High pressure will keep VFR conditions and light winds in place through the period.
Widespread heavy snow is expected today and tonight with significant snow accumulations even in the lower elevations.
Once this warm front passes, we are likely looking at minimal pcpn for much of the late morning/early afternoon.
With high pressure off to the east, a more southerly fetch in the winds will be evident today, and allow for speeds to pick up between 10-15kts across coastal waters, and build seas of 1-2ft today.
An anticyclone located over the Atlantic to the east of Florida has strengthened, tightening the gradient across the Florida Keys. As this high pressure moves away from the United States and begins to dissipate throughout the day, the gradient will relax which will allow for a decrease in winds beginning tonight.
411 AM EST Mon Jan 25 2021 Low pressure will remain over the Maritimes today. High pressure will build into the area Tuesday.
516 AM CST Mon Jan 25 2021 The forecast area is sandwiched between Canadian high pressure dipping into northeast SD and west central MN and a low pressure system moving through the central and southern Plains. That direction at the sfc will help to draw down cooler air, especially in northeast SD where overnight lows will dip into the negative single digits. It will be battling the lack of lift under the high. Temps on Tuesday may be a bit on the warm side given how the high digs further into South Dakota at that point.
snow showers will still be possible over the higher terrain. Temps today will be mostly in the 30s across the plains with the warmer temps in the KTAD area, and lower 30s/a few U20s extending form N El Paso to Kiowa counties. Accumulations will range from 2-4" in the San Juans to trace to 1" amounts the rest of the higher terrain and areas along and west of I-25. Upper low is still on track to pass over the area on Tuesday. Tuesday night will be cold as well, with low teens-single digits east of the mountains and negative single digits over the higher terrain.
The upper level trough that will produce our winter storm later today is in eastern NM and beginning to lift east northeast. This supports the lower snow amounts expected in our area relative to points west.
The warm front is pretty much to our north with a cold front expected later tonight to slowly move through. The higher chances during the day will be across the west and northwest and a few thunderstorms will be possible during the late afternoon hours far west and northwest, especially around sunset. The cold front will swing through tonight before stalling in the southeast by Tuesday morning.
/Issued 322 AM EST Mon Jan 25 2021/ A warm front currently stretches from central Texas through far southwest Georgia to the west coast of Florida. The warm front will slowly push northward this morning, but may increase in forward speed by early this afternoon as the boundary layer winds pick up to 15 to 20kt out of the south. Do think the far NE counties in the CWA will remain situated just north of the warm front until later this evening. The warm front should push into the Tennessee Valley this evening and overnight as a cold front approaches from the west. Models are showing around 700-800 J/kg of CAPE along and ahead of the front, with the highest values Tuesday afternoon.
527 AM 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.
Unseasonably Warm Through Mid-Week Ahead of a Strong Cold Front. High pressure east of the area will shift southeastward over the western Atlc. Expansive mid-level ridging across the Caribbean will keep the Gulf Coast Region with zonal flow aloft, though it may begin to "back" a little more toward the SW late in the period. Expect lows in the 60s areawide, though some normally cooler areas, especially over the interior, may realize U50s.
Freezing temperatures are expected across much the area Tuesday morning.
240 AM MST Mon Jan 25 2021 Our region remains under flat ridging, as a dynamic/cold trof dives along the Pacific coast. Some upstream obs are reporting light snow, and forecast soundings in our east suggest this is possible as the low level moisture deepens. so light freezing drizzle is not out of the question.
709 AM EST Mon Jan 25 2021 A wintry mix is expected today into Tuesday with crossing low pressure. Although freezing drizzle is not a concern attm as higher(colder) clouds continue to move in. some locations may see a light glaze of ice due to freezing fog or soft rime in areas without fog this morning. In coordination with surrounding offices a Winter Storm Warning was issued for the ridges where a prolonged period of freezing rain is expected to result in ice accumulations are forecast to exceed a quarter inch by Tuesday morning. A Winter Weather Advisory was issued for counties north of PGH where freezing rain is expected tonight and into tomorrow morning for northern locations as warm advection continues and sfc temperatures fall to/below freezing. More scattered precipitation will continue Tuesday as the associated upper trough passes.
343 AM CST Mon Jan 25 2021 Early this morning, the synoptic flow was characterized by broad troughing over the western CONUS, and weak northwest flow over the forecast area due to upper troughing over central Canada. For today, expect a wide range in high temperatures, with highs from only a few degrees below zero in the Turtle Mountains, to the lower 20s in the southwest. Snow is expected to slowly taper off from west to east through the morning, although it has already been lingering in the northwest longer than expected, and with the low clouds would not be too surprised if there are scattered flurries through the day. On Tuesday, cyclonic flow aloft continues as a persistent upper low circulates above Manitoba and Ontario.
438 AM MST Mon Jan 25 2021 Updated Aviation Discussion A cooler airmass lingers over the region through Tuesday with low clouds affecting some areas along with patchy fog and possibly some snow flurries tonight into Tuesday morning.
High pressure holds steady through the mid portion of the week as warm air advection begins to warm temperatures. A negatively titled upper level trough begins to punch through the high by the end of the week into the weekend which will bring increasing chances for a weekend system that results from the enhanced forcing from this trough.
343 AM CST Mon Jan 25 2021 The forecast area is sandwiched between Canadian high pressure dipping into northeast SD and west central MN and a low pressure system moving through the central and southern Plains. That direction at the sfc will help to draw down cooler air, especially in northeast SD where overnight lows will dip into the negative single digits. It will be battling the lack of lift under the high. Temps on Tuesday may be a bit on the warm side given how the high digs further into South Dakota at that point.
628 AM EST Mon Jan 25 2021 Aviation - Snow today, some freezing drizzle Tuesday morning - Snow or mixed precip for the weekend - Snow today, some freezing drizzle Tuesday morning Storm still on track for late today and tonight and no changes have been made to the advisory. The DGZ is forecast to dry out after 3 am and there is some lift in the lower levels which could provide a few hours of freezing drizzle early Tuesday morning. Surface temperatures are solidly below freezing through Tuesday so some icing is possible but it will be falling on the snow that has already fallen so travel impacts should be limited.
313 AM MST Mon Jan 25 2021 A cooler airmass lingers over the region through Tuesday with low clouds affecting some areas along with patchy fog and possibly some snow flurries tonight into Tuesday morning.
802 AM EST Mon Jan 25 2021 A wintry mix is expected through Tuesday with crossing low pressure. Recent sfc obs display patchy freezing fog across southern portions of the forecast area as evidence of llvl moisture saturation in the 12Z KPIT sounding, combined with sub-freezing temperature, affects the region. In coordination with surrounding offices a Winter Storm Warning was issued for the ridges where a prolonged period of freezing rain is expected to result in ice accumulations are forecast to exceed a quarter inch by Tuesday morning. A Winter Weather Advisory was issued for counties north of PGH where freezing rain is expected tonight and into tomorrow morning for northern locations as warm advection continues and sfc temperatures fall to/below freezing. More scattered precipitation will continue Tuesday as the associated upper trough passes.
612 AM EST Mon Jan 25 2021 Low pressure will remain over the Maritimes today. High pressure will build into the area Tuesday.
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 middle and end of the work week look to be dry as upper level and surface ridging move into and across the Midwest. As the ridging moves past the region, the upper level flow will turn to the southwest with a good model consensus that a system will advance toward the region for the weekend.
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. Ceilings will lower late tonight, with freezing fog possible at area TAF sites after about 10z through the morning hours on Tuesday.
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.
The forecast area is sandwiched between Canadian high pressure dipping into northeast SD and west central MN and a low pressure system moving through the central and southern Plains. That direction at the sfc will help to draw down cooler air, especially in northeast SD where overnight lows will dip into the negative single digits. It will be battling the lack of lift under the high. Temps on Tuesday may be a bit on the warm side given how the high digs further into South Dakota at that point.
320 PM EST Mon Jan 25 2021 While weak high pressure will provide fair dry weather through the first half of tonight.
Cold front analyzed on surface analysis from Cody to Rawlins to Laramie.
The best moisture and lift will still remain tied to the warm front our south however, which will likely limit any accumulations to around an inch or two for most, maybe up to three right along the lakeshore. Dry air will likely return quickly Tuesday afternoon, rapidly pushing out the remaining snow as the southern cyclone departs. Tuesday Night Through Monday Much of the synoptic snow should be over by Tuesday night as high pressure builds in across the upper Mississippi Valley.
Moisture depth looks to support drizzle this evening before gradually starting to dry out in the lower levels after midnight. Looks like temperatures will stay above freezing while drizzle occurs, but may need to monitor trends late tonight over our western counties as colder air moves in.
1159 AM CST Mon Jan 25 2021 MVFR ceilings lingering at LRD and ALI will gradually improve following a slow-moving cold front that will reach CRP closer to 2-3 PM. The associated cold front has moved southeast into the western Hill Country to near Del Rio. Milder temperatures are expected tonight with drier air and light winds with lows generally in the lower to mid 50s. Highs will be cooler on Tuesday over the coastal plains with expected cloud cover.
1217 PM MST Mon Jan 25 2021 Low stratus persists over the lower elevations, and patchy fog is still present in far SE Montana. These cooler temperatures will help fog to quickly return to the entire area tonight and persist through Tuesday morning. The saturated layer in many areas of south-central Montana looks to be warmer than the DGZ, and hence may occur as freezing drizzle, but the saturated layer cools enough enough tomorrow morning to switch it all to snow showers and/or flurries. With all this being said, there's a very small chance for any precipitation to occur in the first place, so whether freezing drizzle or light snow occurs, impacts will be relatively minor. Vertz Ensemble consensus was for southwest flow to develop as an upper trough digs over the western United States.
A trough over Vancouver island along with a trough over southern CA/NV will continue to produce mostly cloudy conditions with light snow showers over eastern OR through this afternoon and from the Magic Valley south to the NV border this evening into Tuesday morning. The next main weather producer will be a trough currently near 150W and 50N and the associated plume of moisture with subtropical origins.
A cooler airmass lingers over the region through Tuesday with low clouds affecting some areas along with patchy fog and possibly some snow flurries tonight into Tuesday morning.
928 AM MST Mon Jan 25 2021 A cooler airmass lingers over the region through Tuesday with low clouds affecting some areas along with patchy fog and possibly some snow flurries tonight into Tuesday morning.
This will especially be true across NW OK where a cold front is slowly progressing southward with post-frontal stratus accompanying it. Chilly conditions are expected throughout Tue with a much cooler and drier airmass continuing to seep southward. Late Tue another mid to upper trough will move out of the 4 corners region towards OK/KS. Temps will be below freezing throughout tomorrow night across this area so anything that falls won't have a difficult sticking/accumulating.
Land- based sensors show temperatures are in the upper 70s across much of the island chain, although a tad cooler (mid 70s) in portions of the Upper Keys.
Vertz Our region remains under flat ridging, as a dynamic/cold trof dives along the Pacific coast. Some upstream obs are reporting light snow, and forecast soundings in our east suggest this is possible as the low level moisture deepens. so light freezing drizzle is not out of the question.
1231 PM 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.
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. Gusty southerly winds are possible ahead of an approaching cold front, which could lead to some periods of LLWS, especially during the later afternoon and early evening. BW Chattanooga Airport, TN 59 68 46 60 33 / 80 20 20 50 20 Knoxville McGhee Tyson Airport, TN 58 66 44 58 32 / 80 30 10 60 50 Oak Ridge, TN 55 66 41 57 30 / 80 20 10 50 40 Tri Cities Airport, TN 50 65 39 57 29 / 70 40 10 60 80 TN.