Aikyam-Lab/Synoptic-Bench huggingface dataset:
The question is how much drop off there will be this evening before the warmer air starts moving in. Think the higher impact for wind chills will be Thursday night as the system exits off to the east and skies clear.
/issued 900 AM CST Wed Dec 27 2017/ Extended the Winter Weather Advisory until Noon due to icy roads, including bridges and overpasses, as the main impact and temperatures still in the lower to mid 20s. /issued 347 AM CST Wed Dec 27 2017/ (Today and tonight) A Winter Weather Advisory will remain in effect until 9 AM for the ongoing freezing drizzle. These areas of freezing drizzle and fog will continue to persist over the next few hours with temperatures right at or just below freezing in most areas along and north of Interstate 10. The cold temperatures will continue though with high temperatures in the low to mid 30s expected for this afternoon.
Mainly tweaked the precipitation potential across the region for today as a quick moving, weak cold front pushes through the region. Hudson Bay upper low will move to the west today turn the NW flow aloft over Montana to a more WNW direction. Lake effect clouds and light snow around Fort Peck Lake will diminish somewhat today with somewhat warmer temperatures.
Also diminished amounts slightly, with most locations staying under 2 inches of snow, despite the high SLRs of 22-24:1. Very cold temperatures bottomed out overnight generally from the low to mid teens below zero across the region.
Skies should clear out below 10kft this evening but moisture streaming in aloft could start bringing in some cirrus tonight, gradually lowering through the morning hours as the next low pressure system approaches for Thursday evening/night. Temperatures will rebound to above freezing and nearing the lower teens. The lake effect flow regime continues today as westerly winds shift to the northwest as a high pressure around 1045 mb will drift across Wisconsin and the western Great Lakes throughout this afternoon. As the high pressure drifts further through the region, that will help cut winds down enough tonight to where wind chills do not reach advisory criteria like the last couple nights.
Cold air advection continues across Middle Tennessee this morning in the wake of a cold front that moved through yesterday. High temperatures are not expected to even reach the freezing mark for most of the cwa this afternoon, with temperatures plummeting into the teens areawide Wednesday night - the coldest night across Middle Tennessee since January 8, nearly one year ago.
Light fluffy snow will break out ahead of low pressure system currently over lee of Rockies from MT thru WY and south.
Well below normal high temperatures today will resume cooling tonight with continued north winds bringing the freezing line expected to near the Balcones Escarpment. For Thursday the model trends have held on to cooler and overcast skies from the shallow and dense cold air mass with perhaps a few of the western counties warming up to a few breaks in the clouds. With highs well below normals, the continued overcast skies over a surface anticyclone should lead to Thursday night lows to settle near normals.
Locally higher amounts will be possible due to the high snow ratios, especially along portions of the north shore, where 2 to 4 inches of snow is expected.
Latest GOES-East Water Vapor loop clearly shows a mid-level trough dropping southeast across southern southern Saskatchewan Canada.
116 PM EST Wed Dec 27 2017 High pressure will move east into the Ohio Valley today, bringing very cold and dry conditions to the area. As a trough of low pressure moves into the Great Lakes late in the week, there will be some chances for snow on occasion through the weekend.
Current temperatures are generally a few degrees cooler than at the same time yesterday.
High pressure ridge over the Red River valley at 09z and it will slowly move east. Cooler air will follow a short wave trough Thu night into Fri. Broad long wave trough over central and eastern Canada sharpens and shifts into eastern North America by Tue. Long wave ridge builds over western Canada.
Precipitation will gradually end west-to-east heading into early this afternoon as a slow-moving cold front sags south across the area, ushering in drier and slightly cooler air.
127 PM EST Wed Dec 27 2017 Arctic high pressure crosses tonight into Thursday.
Updated the hourly temperature curve, as most areas started out a little warmer than expected, but did not adjust the day time highs, given the cold air settling into the region. In fact, wind chill factors will be in the lower 30s.
This slight waa will help bumps highs into the lower teens everywhere will plenty of sunshine to start the day.
However, temperatures remain in the mid 20s across the Big Country and roads remain icy, especially bridges and overpasses. /issued 900 AM CST Wed Dec 27 2017/ Extended the Winter Weather Advisory until Noon due to icy roads, including bridges and overpasses, as the main impact and temperatures still in the lower to mid 20s. /issued 347 AM CST Wed Dec 27 2017/ (Today and tonight) A Winter Weather Advisory will remain in effect until 9 AM for the ongoing freezing drizzle. These areas of freezing drizzle and fog will continue to persist over the next few hours with temperatures right at or just below freezing in most areas along and north of Interstate 10. The cold temperatures will continue though with high temperatures in the low to mid 30s expected for this afternoon.
148 PM MST Wed Dec 27 2017 High clouds have moved over northern parts of the area this afternoon with the approach of a weak upper level trough in dry northwesterly flow. High pressure over the desert southwest will keep the rest of the area clear this afternoon and evening. Mid level warm advection will warm things up heading into the weekend with some valleys reaching the low 50's.
High pressure over the SW U. The synoptic pattern continues to be a broken record with a large Hudson Bay low steering arctic air over areas east of the Rockies, and a mean upper level ridge over the West Coast blocking any significant moisture plumes from any direct hit on Utah/Colorado through this period.
223 PM EST Wed Dec 27 2017 Arctic high pressure crosses tonight into Thursday.
236 PM CST Wed Dec 27 2017 High pressure will move from IA east to the eastern Great Lakes.
Snow continues this morning in southern Idaho along a southward moving cold front.
High pressure will continue to bring dry weather through today. Mid and high clouds continue to flow over the northern periphery of the high pressure system just off the West Coast.
944 AM CST Sat Dec 23 2017 Little change for today outside of observed trends trough 15 UTC this morning.
/Issued 505 PM CST Fri Dec 22 2017/ An upper level low pressure system currently moving across the southern Texas Panhandle is causing snow flurries or a brief period of light snow in this area as of this writing. The next reinforcing cold front is then expected to move across the OK and TX Panhandles Saturday night, leading to another setback in temperatures on Sunday.
Overnight, light and variable winds will prevail and due to drier conditions having been ushered in by a cold front, fog may be hard-pressed to develop. /issued 259 AM CST Sat Dec 23 2017/ The last of the convection is making its way e of our region this morning, and a much cooler airmass is taking hold in the wake of a cold front. Warmer temps expected for Sunday, as a brief return of sly winds ahead of another cold front will help us to reach into the 50s to near 60 for portions of the region. Impulse in nw flow aloft and associated cold front will bring widespread cloud cover, but moisture expected to be too limited to see any precip with the fropa.
Highest rainfall amounts overnight were located north of I-40 and west of I-65, and the cold front as of 230 am is in between Springfield and Nashville. The cold front is oriented from southwest to northeast, and again as of 230 am is over Portland in the north, and Lobelville in the south. High temperatures will be in the morning as temperatures fall during the day behind the cold front. Temps around sunset look to be in the low to mid 40s across the mid state. In the evening, temps will fall into the low to mid 30s. Depending on the location of the secondary cold front, the transition to snow may be delayed enough to keep accumulations at bay.
302 AM PST Sat Dec 23 2017 High pressure aloft will bring a warming trend for inland areas through Christmas.
525 AM EST Sat Dec 23 2017 Rain is expected with crossing low pressure today. Snow chances return Sunday with another area of low pressure. An associated cold front is expected to cross the area later this morning/early afternoon as the low advances NEWD to srn New England. Advisory level snow of 2-4 inches is possible near the I 80 corridor and in the ridges, as the flow shifts NW and results in some lake and terrain enhancement on the wrn side of the departing low Sunday night.
610 AM CST Sat Dec 23 2017 Colder air is settling into the area on the heels of a cold front that passed through the forecast area during the afternoon and evening hours. A broad upper level trough over the area will send another surge of cold air in our direction tonight, accompanied by a band of cold air advection and frontogenesis driven snow showers from this afternoon through this evening. The clouds overnight have kept our temperatures from dropping off, but they will not recover much today either as even though we should see decreasing cloud cover for at least this morning, the approaching cold front will just bring them back again this afternoon and I expect greater cloud cover for tonight and Saturday.
Similar environment will hold tonight and again Sunday night, mainly over western and interior portions of South Florida, as high pressure dominates, bringing mostly clear skies, light winds, and warm temperatures. The trailing cold front will weaken as it enters Florida Sunday, then crosses South Florida on Christmas Day. This front will be moisture starved and have little in the way of drier air or cooler air, so expect no rainfall Christmas with temperatures only a degree or two cooler than the weekend values. The weekend values will consist of maxima in the low 80s and minima ranging from around 60 degrees northern interior to low 70s along the Atlantic coast.
Arctic weather conditions expected across northeast Montana An upper level trough and surface cold front pushing through the area may generate enough lift for isolated snow showers at times through the weekend.
1041 AM EST Sat Dec 23 2017 Rain is expected with crossing low pressure today. In wake of low pressure crossing midday there could be a short window of wind gusts in the mountains in the 30 knot range given pressure rises between 19-22Z. Advisory level snow of 2-4 inches is possible near the I 80 corridor and in the ridges, as the flow shifts NW and results in some lake and terrain enhancement on the wrn side of the departing low Sunday night.
A strong trailing cold front stretches southwest from the low pressure center across west Tennessee into northeast Mississippi. This will help to push a reinforcing arctic cold front across the area on Sunday. Arctic high pressure will build in Christmas Eve night and Christmas Day with clearing skies and cold temperatures. JLH A frontal boundary extends from an area of low pressure near the AR/LA border northeast to near KAWM to KPHT. As low pressure moves NE this evening the front will start moving east as a cold front eventually spreading into KTUP later tonight with conditions lowering to IFR.
Most locations are running several to as much as 10 degrees warmer compared to 24 hours ago as the temperatures aloft moderate and widespread high level clouds move over the region. With that said, freezing temperatures persist in many valley locations, especially the southern Salinas Valley where 20s are being reported.
Weak upper level ridging combined with weak offshore sfc flow will continue to bring mild daytime temperatures and cool nights through Christmas Day.
As ridge axis drops to central CWA today, light flow will acquire more of a southerly component and with skies averaging partly sunny, temps will be similar across entire CWA, peaking in the lower 80s inland and near 80 along the beaches. SE flow becoming S across most waters by mid day, mainly AOB 10 knots as ridge drops slowly south through the waters. SE component likely to hold on a little longer over the southernmost waters given postion of ridge axis.
With plenty of sunshine this afternoon, we are expecting to see temperatures several degrees warmer today, with a lee trough strengthening over the west Texas/New Mexico border. Light winds today should become more southwesterly overnight ahead of the next cold front. Temperatures overnight will be above freezing for most areas, but low-lying areas and river valleys could still see lows in the lower 30s.
Chattanooga Airport, TN 63 41 51 29 / 100 10 10 10 Knoxville McGhee Tyson Airport, TN 64 39 51 28 / 100 10 20 20 Oak Ridge, TN 60 38 49 27 / 100 10 20 20 Tri Cities Airport, TN 59 37 51 26 / 100 20 20 40 NC.
905 AM EST Sat Dec 23 2017 Rain is expected with crossing low pressure today. In wake of low pressure crossing midday there could be a short window of wind gusts in the mountains in the 30 knot range given pressure rises between 19-22Z. Advisory level snow of 2-4 inches is possible near the I 80 corridor and in the ridges, as the flow shifts NW and results in some lake and terrain enhancement on the wrn side of the departing low Sunday night.
A polar cold front that has persisted just south of the Washington state line is beginning to move southward early this morning. Highs will be in the 20s to around freezing with some teens in the mountains.
Cold front approaches from the NW and brings slight chance of showers to inland SE GA while dense fog and stratus still possible across NE FL as it develops along the Big Bend/GOMEX and tracks NE through the overnight hours. Light S-SW flow will continue today and increase slightly ahead of cold front tonight to 10-15 knots.
1022 AM EST Sat Dec 23 2017 A cold front stretches from New England to the central Gulf Coast and is progressing eastward. The broad, mean-layered ridge remains centered across the Florida Keys/NW Cuba/S Florida. A few lines of cumulus are present across the Straits of Florida, positioned perpendicular to the island chain, with nearly cloudless skies across the cooler coastal waters of the gulf. The mean-layered ridge will linger across the Keys through tomorrow night, so expect the current temperature pattern to remain.
Water vapor loop indicated an upper level low pressure system over northern MAN. Upper low will settle into northern Ontario by 12Z Tue. Wed morning is expected to be the coldest morning with high pressure overhead. High amplitude long wave ridge over AK weakens considerably through the extended/Tue-Fri/. Also long wave trough centered over Ontario weakens and extends into the north central Atlantic by the end of the period.
High pressure will move in with fairly weak winds after an initial surge of northerly winds earlier in the day. Highs Sunday will be cooler overall under the high. To the northeast, expecting cooler highs with 30s by Hays.
Cold front is very well defined with narrow line of convection that is moving through Acadiana this morning. Much colder tonight but temperatures likely to stay well above freezing.
544 AM CST Sat Dec 23 2017 Latest 08z surface analysis shows weak cold front extending from southern Ontario Canada into northern Iowa. Metars in southeast Minnesota and western Wisconsin are reporting flurries and low stratus clouds in associated with the cold front. First piece of energy rotates around the upper level trough into the Central Plains Sunday.
Northerly winds will continue today but will be light and southerly by tomorrow morning before the passage of another cold front. A short wave moving across the Plains Sunday forces a strong cold frontal passage midday to afternoon.
SHORT TERM (Now through Sunday): The cold front has cleared through the region over the last few hours with the isold to sct shower activity decreasing as more stable air moves in from the northwest. CAA will prevail today and tonight as surface ridging spreads over the region.
These winds will weaken after 00 UTC, then increase from the north with the passage of a cold front after 06 UTC. /issued 402 AM CST Sat Dec 23 2017/ The upper-level trough that brought us wintry precipitation has exited the area. In the system's wake, a warmer, but seasonably cool day is expected across the area. Breezy northerly winds behind the cold front will make it feel quite cold.
/issued 321 AM CST Sat Dec 23 2017/ Zonal flow will persist through the next 24 hours before a passing trough to our north shifts the flow regime a bit more northwesterly on Sunday morning.
A cold front will move across the area today, entering southeast Mississippi this morning and exiting the area late this afternoon or early this evening. The highest rain chances will be across northern areas with chance pops to the south.
402 AM CST Sat Dec 23 2017 The upper-level trough that brought us wintry precipitation has exited the area. In the system's wake, a warmer, but seasonably cool day is expected across the area. Breezy northerly winds behind the cold front will make it feel quite cold.
1027 AM EST Sat Dec 23 2017 With high pressure over the area, no significant changes to the forecast were required this morning. Similar environment will hold tonight and again Sunday night, mainly over western and interior portions of South Florida, as high pressure dominates, bringing mostly clear skies, light winds, and warm temperatures. The trailing cold front will weaken as it enters Florida Sunday, then crosses South Florida on Christmas Day. This front will be moisture starved and have little in the way of drier air or cooler air, so expect no rainfall Christmas with temperatures only a degree or two cooler than the weekend values. The weekend values will consist of maxima in the low 80s and minima ranging from around 60 degrees northern interior to low 70s along the Atlantic coast.
Extensive cloud cover has blanketed northern California under a dirty ridge of high pressure. This cloud cover has aided in preventing strong radiational cooling; temperatures across the region are running upwards of 15 degrees warmer than 24 hours ago. High pressure will remain in control across the region through early Sunday, bringing dry weather and mostly light winds. The upper ridge will flatten on Sunday as a disturbance moves into the Pacific Northwest.
709 AM EST Sat Dec 23 2017 Rain is expected with crossing low pressure today. An associated cold front is expected to cross the area later this morning/early afternoon as the low advances NEWD to srn New England. Advisory level snow of 2-4 inches is possible near the I 80 corridor and in the ridges, as the flow shifts NW and results in some lake and terrain enhancement on the wrn side of the departing low Sunday night.
Ahead of this wave, a warm advection regime continues to produce fairly widespread precipitation across valleys north of I-80, as well as across the higher terrain northern Utah.
Cold front currently just east of BNA moving very slowly east as weak wave along it down in NW AL slows its progress. Showers continue to move across the area with the cold front.
438 AM CST Sat Dec 23 2017 Cold front well southeast of the area and departed the coastal waters in the last hour. Cooler night tonight with drier air in place and mostly clear to clear skies/light-calm winds. The cold front should reach the northern CWA by noon Sunday and off the coast before 6 pm. Much drier air plows through with a 1035mb over NTX weakening and settling into SETX Christmas Day with temperatures again only warming into the lower to mid 50s.
For the plains, mainly high clouds today as the lower clouds will be skirting along the eastern and northern borders.
A strong trailing cold front stretches southwest from the low pressure center across west Tennessee into northeast Mississippi. This will help to push a reinforcing arctic cold front across the area on Sunday. Arctic high pressure will build in Christmas Eve night and Christmas Day with clearing skies and cold temperatures. JLH 12Z TAFs Precipitation chances expected to end this morning as high pressure builds in at TAF sites behind a cold front.
/issued 449 AM CST Sat Dec 23 2017/ SHORT TERM (Now through Sunday): The cold front has cleared through the region over the last few hours with the isold to sct shower activity decreasing as more stable air moves in from the northwest. CAA will prevail today and tonight as surface ridging spreads over the region.
Yet another cold front will arrive the morning of Christmas Eve, temps will be near steady in the afternoon.
The typical cold spots, like Dixie and Elk City in Idaho, and Polebridge and Butte in Montana to name few, could drop into the teens and 20's below zero. North-central Idaho will see the higher accumulations this go around, with widespread 2 to 5 inches across the valleys, and 5 to 7 inches for the benches above Orofino, Pierce and White Bird Hill. The higher values will be along and south of the I-90 corridor.
Fast moving clipper system will move into the central Plains late Saturday night into Sunday morning with a few snow flurries possible across far northeast Oklahoma and northwest Arkansas with the next strong cold front.
Temperatures will likely only warm into the 30s/40s today and winds will remain northwesterly behind yesterday's cold front.
Some brief patches of freezing fog may be possible at times while the temperatures plummet. The typical cold spots, like Dixie and Elk City in Idaho, and Polebridge and Butte in Montana to name few, could drop into the teens and 20's below zero. North-central Idaho will see the higher accumulations this go around, with widespread 2 to 5 inches across the valleys, and 5 to 7 inches for the benches above Orofino, Pierce and White Bird Hill. The higher values will be along and south of the I-90 corridor.
Gradient winds over the area continues to produce windy conditions, especially across the higher elevations. Chattanooga Airport, TN 65 41 51 29 / 100 10 10 10 Knoxville McGhee Tyson Airport, TN 66 39 51 26 / 100 10 20 20 Oak Ridge, TN 65 38 49 26 / 100 10 20 20 Tri Cities Airport, TN 64 37 51 22 / 100 20 20 40 NC.
428 AM MST Sat Dec 23 2017 Current surface analysis shows cold front well south and west of the forecast area, with weak high pressure centered over northern SD. Upper level analysis shows long wave trough remaining across much of Canada and the northern US, with low centered over southern Hudson Bay.
Mid level ridge will keep the region dry tonight, with temperatures dropping back into the upper 20s and lower 30s.
Surface winds progressively shifting out of the northeast as strong high pressure builds over the Deep South, and slides toward the Seaboard. A weak cool front will shift south of the area as high pressure builds in behind.
Any lingering rain will be ending early Sunday, but clouds may remain rather stubborn, which will keep temperatures a bit cooler than today, but still above normal for mid December.
High pressure and a brief moderating trend in the temperature are expected by Sunday.
High pressure aloft will build back into the area beginning Sunday.
Resultant downstream ridge across the Southeast will keep the area dry and mild today with some high clouds of Pacific origin passing by throughout the day. Sfc is dominated by high pressure. Upper level jet will be a mainstay over the Tennessee Valley and providing energy to the local area until actual upper low eventually kicks out and provides its own dynamics.
but is becoming more westerly this morning as an upper trough crosses the western CONUS. Aside from some lingering snow showers, drier weather is expected Sunday as the main trough axis crosses the CWA.