Aikyam-Lab/Synoptic-Bench huggingface dataset:
1016 AM EST Mon Jan 4 2021 High pressure ridging is likely over the area early this week. But, the northwest flow will last for a few days, keeping it more cloudy than a typical high pressure set up. Large scale subsidence has overspread the region early this morning behind departing upper low. However, residual low level moisture, combined with light upslope flow, will continue to produce spotty drizzle, freezing drizzle or flurries over the Allegheny Plateau. Cloud cover will keep temperatures from rising much today, with highs likely ranging from the low 30s over the highest ridges of the Alleghenies, to the low 40s across the Lower Susq Valley.
As the center of the high shifts to the east, winds will quickly return to a southerly component tonight. Although a slug of high- level subtropical moisture will get caught up in the southwesterly flow aloft and carry plenty of thin cirrus over the region during the day, temperatures will still rebound into the lower and middle 60s.
Additional cloudiness and some moisture will begin to move in for the second half of the afternoon as a weak cold front is set to pass through tonight.
112 PM EST Mon Jan 4 2021 Aviation - Chance for wintry precipitation tonight - Continued cloudy to mostly cloudy with fog possible at times - Chance for wintry precipitation tonight Guidance continues to show light precipitation moving in tonight as a cold front drops down through the area. a small risk for freezing drizzle could arise. For now we are not confident enough to feature the freezing drizzle in the forecast. - Continued cloudy to mostly cloudy with fog possible at times Looking at the model overviews in Bufkit shows the low level rh remaining high. If thicker fog could form and temperatures were near or below freezing. LIFR and VLIFR are expected tonight as a trough moving through the area brings some light snow. This is ahead of the cold front.
SW winds will become westerly ahead of a weak cold front this aftn.
120 PM EST Mon Jan 4 2021 Weak upper level low pressure near the Ohio River Valley will drift eastward today as weak high pressure persists at the surface. A weak trough will move east across the Central Great Lakes on Tuesday.
Winds will remain light/sly this afternoon as high pressure prevails amidst building heights aloft. Chattanooga Airport, TN 55 41 50 31 52 / 0 10 0 0 0 Knoxville McGhee Tyson Airport, TN 51 40 46 30 48 / 10 30 20 10 0 Oak Ridge, TN 51 38 46 29 48 / 10 30 10 0 0 Tri Cities Airport, TN 49 34 45 30 44 / 10 20 40 20 0.
1230 PM EST Mon Jan 4 2021 High pressure ridging is likely over the area early this week. But, the northwest flow will last for a few days, keeping it more cloudy than a typical high pressure set up. Residual low level moisture, combined with light upslope flow, will continue to produce spotty drizzle, freezing drizzle or flurries over the Allegheny Plateau. Cloud cover will keep temperatures from rising much today, with highs likely ranging from the low 30s over the highest ridges of the Alleghenies, to the low 40s across the Lower Susq Valley.
A ridge of high pressure is exiting to the east as a weak and dry cold front moves into East TX and NW LA. This front will move through the local area tonight with high pressure rebuilding from the north.
Highs today will gradually increase to the lower 50s with lows tonight in the lower 30s. /issued 329 AM CST Mon Jan 4 2021/ A low pressure continues pushing northeastward away from our area. Dry weather for the next 2 days as a ridge builds over the area.
In the extended at IAH, look for onshore flow to return later in the day in advance of a midweek cold front. With high pressure to our SE and upper level ridging developing overhead, weather conditions will stay on the dry side with light and variable winds and mostly sunny skies. Tonight, cooler and drier air mass will move across the northern portions of the CWA, while a more humid air mass remains along the southern portions. This will not do much with respect to rain, since we will still be under the influence of the mid to upper level ridging, but at least we will get some clouds first developing along the southwest locations gradually expanding into the rest of the CWA later on Tuesday.
1059 AM CST Mon Jan 4 2021 Dense freezing fog currently lingers across northwest Iowa as light southeasterly flow has been advecting moist air over the snowpack. Clear skies and a quick return of ridging aloft allows for redevelopment of a surface inversion tonight.
A narrowing Upper Midwest mid level trough will amplify southeast in response to a 120 kt upper jet digging toward the Mid MS Valley. Forcing for ascent with this feature will have the potential to produce some light mixed precipitation later tonight into early Tuesday morning along an eastward advancing low-mid level trough/shear axis. There is then some threat for precip to end as patchy freezing drizzle Tuesday morning where the trough lingers and mid levels dry out.
After a cold and frosty start to the day, temperatures have warmed into the lower 40s in most locations thanks to a mostly sunny sky. With high pressure at the surface setting up just east of the area across the Southern Appalachians, winds will veer to the south and allow some air mass modification as temperatures should climb into the mid to upper 50s by this afternoon. A weak front associated with an upper-trough over the northern Plains will begin to approach the area late in the day into the evening. Upper level heights will rise on Tuesday as ridging builds in from the west.
919 AM CST Mon Jan 4 2021 After a cold and frosty start to the day, temperatures have warmed into the lower 40s in most locations thanks to a mostly sunny sky. With high pressure at the surface setting up just east of the area across the Southern Appalachians, winds will veer to the south and allow some air mass modification as temperatures should climb into the mid to upper 50s by this afternoon. A weak front associated with an upper-trough over the northern Plains will begin to approach the area late in the day into the evening. Upper level heights will rise on Tuesday as ridging builds in from the west.
High pressure at the surface and aloft will make for a quiet weather day Tuesday.
1028 AM EST Mon Jan 4 2021 High pressure ridging is likely over the area early this week. But, the northwest flow will last for a few days, keeping it more cloudy than a typical high pressure set up. Residual low level moisture, combined with light upslope flow, will continue to produce spotty drizzle, freezing drizzle or flurries over the Allegheny Plateau. Cloud cover will keep temperatures from rising much today, with highs likely ranging from the low 30s over the highest ridges of the Alleghenies, to the low 40s across the Lower Susq Valley.
A shallow boundary layer moisture layer with weak, troughy flow aloft will maintain clouds, patchy drizzle as some isolated to scattered showers of rain and light snow tonight. By Tuesday morning, a short wave trough will have moved through the area switching winds around to the NW and WNW in a more favorable direction for upslope and lake enhancement snow showers and flurries. Still, given the marginal influence, accumulations should be minimal allow for no more than an inch or inch and a half in the higher elevations.
1237 PM EST Mon Jan 4 2021 High pressure will remain over the area through the middle of the week.
Temperatures will climb into the lower 60s for much of the area by later this afternoon.
118 PM EST Mon Jan 4 2021 Low pressure heads east of Long Island Monday and meanders off Nova Scotia. Weak high pressure builds in from the west through midweek. Another coastal low pressure system is possible this weekend. Temperatures today, under the cloudy skies and northerly flow, will top out in the lower 40s from NYC on east, and in the upper 30s to near 40 across the interior. Unsettled weather continues as the upper low and general trough pattern over the northeast stay in place on Tuesday.
A few snow showers will be possible as well, mainly in the higher elevations. Temperatures will fall into the lower 30s tonight. Thus will expect a chance of freezing drizzle again. During the night, an approaching trough will swing winds around to the WNW and added lift will change the drizzle over to more snow showers and flurries. By Tuesday morning, a short wave trough will have moved through the area switching winds around to the NW and WNW in a more favorable direction for upslope and lake enhancement snow showers and flurries. Still, given the marginal influence, accumulations should be minimal allow for no more than an inch or inch and a half in the higher elevations.
1025 AM MST Mon Jan 4 2021 09z surface analysis had cold front well southeast of the CWA with weak ridge building into the CWA. Water vapour had upper ridge building into the northern Plains behind upper trough over the Midwest. Today/tonight, upper ridge shifts through the northern Plains into the Midwest as upper trough moves into the northern Rockies. Have painted ring of warmer overnight lows for these areas. Tuesday, upper trough move through the region with main energy diving east/southeast into the central Plains. Moisture won't be plentiful, but synoptic forcing ahead of jet streak as well as modest low level frontogenisis will support a band of snow/rain along advancing cold front.
1253 PM EST Mon Jan 4 2021 Low pressure continues to move east of Cape Cod today.
A warm front continues to lift north across the forecast area mainly providing light precipitation over northern Oregon and Washington. Some southerly breezy to windy conditions are accompanying the warm front mainly over Oregon this morning and will continue through the day before a cold front moves through the area later today. The cold front will lower snow levels late today and overnight but with precipitation decreasing to showers. Southerly winds will switch to westerly behind the cold front and then decrease overnight.
(This evening through Tuesday) Cold front was pushing south of I-10 this afternoon with north winds of 10 to 15 mph behind it.
Winds will remain light/sly this afternoon as high pressure prevails amidst building heights aloft. High pressure will prevail this afternoon/evening before an upper wave moves in overnight. With that, a cold front will sweep through the area favoring veered nwly flow and increased moisture. CDG Chattanooga Airport, TN 41 52 30 52 36 / 10 10 0 0 20 Knoxville McGhee Tyson Airport, TN 40 49 30 48 32 / 20 20 10 0 10 Oak Ridge, TN 38 49 29 48 32 / 20 20 0 0 10 Tri Cities Airport, TN 34 44 30 44 28 / 30 30 10 0 10.
Still looking at a freezing rain potential for Tuesday morning. A cold front moves through the area late tonight and Tuesday morning with enough moisture for a chance of mixed precipitation. Temperatures will fall below freezing this evening in most areas. Meanwhile, there will be an above freezing layer aloft which will result in any precipitation that occurs being a mix of light rain, light freezing rain and light snow depending on surface temperatures and how warm the warm layer aloft ends up being.
258 PM CST Mon Jan 4 2021 (Issued 258 PM CST Mon Jan 4 2021) Tonight and Tuesday night: There is ongoing dense freezing fog across southwestern Wisconsin this afternoon. The visibilities are expected to improve slightly as the dense fog lifts with the passage of weak cold front this evening. As the front passes it is expected to bring a light wintery mix of freezing drizzle, sleet, and snow. Winds will shift to northwesterly behind the weak cold front. This would keep the dense freezing fog around for yet another night. High pressure and upper level ridging is then expected to move across the Great Lakes Region starting Tuesday and continuing through the mid-week. Without much of change in the airmass over southern Wisconsin expected, coupled with the light winds under high pressure, patchy fog and clouds are expected to linger Tuesday.
Brief period of mid/upper level ridging expected for Tuesday as our low level flow turns more south/southeasterly. Temperatures again on the warmer side of normal are expected with widespread 30s for most. Big question for our area is where does this low end up migrating too before beginning its prolonged pivot. Guidance is in fairly good agreement that there will be a somewhat prolonged light snow event where this low decides to pivot and carries the longest residence time but agreement on where exactly this is across our more local area is far lower.
234 PM CST Mon Jan 4 2021 Passing short wave trough with associated surface boundary continues to scour fog and low ceilings in shallow inversion out from west to east.
As the flow aloft becomes more zonal early this evening, then southwest late, the low and mid level flow increases with surface pressure falls. Gradients still favor strong winds across our Wyoming wind prone locations, and these strong winds may spread eastward across Central Laramie County and Cheyenne, therefore we have continued the High Wind Watch there.
/Tonight through Tuesday Night/ Northwest flow aloft to prevail ahead of an upper-level ridge that will become centered across the ArkLaTex on at the end of the short term period on Tuesday night. This setup will allow for mostly clear skies through Tuesday with clouds returning on Tuesday evening as surface and upper-level ridge begin to shift east allowing for a return of southerly moisture areawide. With clouds returning from the south and west, temperatures on Tuesday night to be slightly warmer.
1022 AM EST Mon Jan 4 2021 A cold front is currently passing through the Florida Keys island chain on this late Monday morning. In terms of temperatures, it will be noticeably cooler tonight, with temperatures likely dropping into the upper 50s to near 60 in the typical cool locations of Big Pine Key and the Upper keys and lower 60s elsewhere. It is worth noting that the low temperatures will be highly dependent on how quickly skies clear over the island chain.
Mid-level temperatures will generally remain above freezing into Tuesday morning.
Temperatures are hovering near 70 this afternoon, and dewpoints have dropped into the lower to mid 60s. Should mid-level clearing occur sooner than currently forecasted, low temperatures may drop to near 60 in some of the typical cooler island communities.
Broad mid- upper level troughing has set up over the eastern half of the U.
Currently, strong northwest flow aloft with a mid level trough over Minnesota and a long wave ridge across the Northern Rockies. For tonight, upper level ridge develops east into the Northern Plains as a strong S/WV trough moves into eastern Montana. Increasing mid/upper level cloud cover along and ahead of the ridge, with already increasing clouds across eastern Montana early this afternoon. Some guidance suggested freezing rain or sleet west, though with the initial dry boundary layer, this window will be short lived if open at all, as we wetbulb out to subfreezing temperatures aloft.
309 PM EST Mon Jan 4 2021 High pressure will keep fair weather over the region tonight. A pair of closed lows and a cold pool aloft will combine to produce flurries and snow showers Tuesday and Tuesday night along with minimal accumulation.
1126 AM CST Mon Jan 4 2021 Main focus is with the mid-week upper trof/low which deepens across the central Plains/Ozarks with chances for rain/snow. However, milder westerly flow off the high Plains behind a frontal passage should advect/scour this out quicker before mid-morning, so the Dense Fog Advisory may be cancelled early. Otherwise, the downslope warming will also portend to a warmer day, though snow covered areas will still lag a bit. The progressive upper trof over the Pacific will move inland and across the western CONUS tonight before emerging across the central/northern high Plains Tuesday afternoon.
1119 AM CST Mon Jan 4 2021 (Today and tonight) A weak and dry cold front will move south across our area today. Overnight lows are expected to be in the upper 20s to lower 30s across our central and southern counties, and in the lower to mid 30s across the Big Country.
That said, some patchy dense fog my remain in place this afternoon, especially along ridge tops. Passing short wave trough with associated surface boundary continues to scour fog and low ceilings in shallow inversion out from west to east.
1011 AM EST Mon Jan 4 2021 Weak high pressure will persist at the surface through the day as an elevated area of low pressure moves eastward near the Ohio River Valley. A weak trough will move east across the Great Lakes Region on Tuesday.
123 PM EST Mon Jan 4 2021 High pressure will build over the region through the middle of the week with a series of upper level disturbances crossing the region.
Tuesday morning we'll see an increase in cloudiness associated with a PV streamer connected to an upper-level trough centered over the Great Lakes region. This cloudiness will be associated with the trough axis and is expected to be out of our region by late morning/early afternoon. Behind this trough we'll begin to transition into a ridging pattern that will keep us under large scale subsidence through the end of the near term. Expect overnight lows to be between the low 40s (inland) and upper 40s (near the coast). Expect daytime highs to be in the low to mid 60s with higher values being along the coast and cooler values in SE Alabama/SW Georgia.
High pressure will dominate the pattern across the area into the upcoming weekend. Elsewhere, additional mid and high level cloud are approaching from the west, ahead of the next trough. Otherwise, an upper trough currently over the northern Midwest is expected to pass through the local area during the early morning hours of Tuesday. Model data currently suggest the low level flow may be strong enough to mix out the fog, at least into a low cloud deck. Model data suggest tonight's upper trough will still be in the process of moving through the eastern zones Tuesday morning. Otherwise, generally quiet weather is expected for the rest of the short term, as upper ridging develops over the Great Lakes.
In the low levels, a weak closed low develops to the south with an inverted trough to the north, setting up more or less along the James valley.
The 19Z MSAS surface analysis indicated a cold front that extended from Duluth to Rochester to just east of Des Moines. Farther to the west, a ridge of high pressure was located over the central and northern Plains. Any snow accumulation would be one-quarter of an inch or less, but add in any freezing precipitation and there could be some slick spots on area roads. Despite the clearing line behind the cold front, forecast soundings indicate that low-level moisture will not get scoured out by the front. The ridge of high pressure will move into the region on Tuesday. However, that persistent low-level moisture layer near the surface and the low sun angle, may make it take a while before any sun pokes through the clouds.
Today should be the last day of these well above-average temps as a cold front passing through later tonight will knock temps back down to near seasonal normals. Could see a little bit of moisture on the back side of the low, translating into some showers late tonight into the early morning hours tomorrow along the Plateau. An upper-level ridge will move into the region tomorrow keeping prcp chances out of the forecast for a couple of days.
A cold front will push across the region overnight scouring out the moisture. High pressure will build into the Midwest behind the front.
240 PM CST Mon Jan 4 2021 Dry weather continues this evening as ridging aloft gives way to a weak upper trough that moves through tonight. This will bring a weak surface cold front through the area, shifting winds to the northwest and lowering high temps into the lower to mid 60s for Tue.
A high pressure will remain over central/eastern Gulf of Mexico today, keeping a north-northwest wind flow over the area. Lows tonight will drop to the 40s from Okeechobee and St Lucie counties northward, with some locations in Lake and interior Volusia counties reaching the lower 40s for a few hours.
Northwest winds aloft will gradually become more zonal as the ridge traverses the plains tonight into tomorrow.
High pressure aloft and very dry air aloft have created a strong low-level inversion that has trapped moisture near the surface. But if we do clear at all this morning, areas of dense freezing fog could develop, as is currently occuring across northern and western Illinois. An elongated northern stream trough will swing through the area tonight into Tuesday morning. Better lift ahead of the trough axis may initially saturate the atmosphere high enough up to reach the DGZ and produce snow, but the moisture quickly becomes more shallow overnight, and drizzle or freezing drizzle become more likely. Precipitation will then end by afternoon, and temperatures should rise into the mid-30s, mitigating any surface freezing.
Good news approaching short wave trough should push surface boundary through from west to east this afternoon so expect vast improvement as day wears on, especially west of Mississippi River where sunshine should break through. Very narrow band of precipitation also associated with short wave trough but bulk of echoes have been north and northwest of area closer to wave. Could also not rule out a bit of drizzle/freezing drizzle ahead of the deeper lift, especially near and east of the MS River, with the RAP showing weak ascent in the cloud layer from low-level warm advection prior to deeper saturation. If fog/low clouds become widespread through the overnight, they may be slow to erode again on Tuesday given the weak mixing as the ridge axis passes overhead.
Temperatures will be seasonable, with highs in the lower to mid 30s and lows in the 20s.
An upper low will move across the region quietly early today. High pressure maintains dry weather Tuesday through Tuesday night.
Beginning around 07Z on 1/5 a narrow BKN cloud deck associated with an upper-level trough begins to move across the area from west to east, starting with DHN and ECP and ending by 14Z on 1/5 at TLH and VLD. Temperatures overnight are expected to drop into the low 40s. High temperatures today are forecast to be in the low 60s for much of the area.
Have slight chance PoPs across the higher terrain of north/northeast Georgia from 03z to 16z Tuesday to capture this potential. Given the cloud deck in place through Tuesday morning, low temperatures will generally be in the 40s, which is a good 5-10 degrees warmer than last night. Ridging and northwest flow will build in on Tuesday, making for sunny to mostly sunny skies and dry conditions.
209 PM CST Mon Jan 4 2021 Surface MSLP pattern will respond quickly going into Tue ahead of the next shrtwv trof and assocd cold front. Even though a front passes today the high temps on Tue will not be too much different from today, some clouds across the n.
1124 AM EST Mon Jan 4 2021 Low pressure heads east of Long Island Monday and meanders off Nova Scotia. Weak high pressure builds in from the west through midweek. Another coastal low pressure system is possible this weekend. Temperatures today, under the cloudy skies and northerly flow, will top out in the lower 40s from NYC on east, and in the upper 30s to near 40 across the interior. Unsettled weather continues as the upper low and general trough pattern over the northeast stay in place on Tuesday.
1020 AM CST Mon Jan 4 2021 Trough axis is now transitioning over northwest MN with clearing west to east. Despite CAA aloft westerly flow/daytime mixing should still keep temperatures relatively stable (either side of freezing) through this afternoon. Band of snow and possibly mixed precip quickly moving east is between Detroit Lakes and Park Rapids along the cold front and will be east of the forecast area by 9am. As this area of precip moves toward Fargo Moorhead and into west central MN some CAM guidance expands its coverage and with temps below freezing a glaze of ice will be possible impacting the morning commute.