Aikyam-Lab/Synoptic-Bench huggingface dataset:
306 PM CDT MON SEP 5 2016 18Z surface data has high pressure over the eastern Great Lakes with a front running from northwest Minnesota into northeast Colorado. Boundaries generated from this thunderstorm complex may get into the highway 20 corridor by sunrise. As the front approaches the area Tuesday afternoon, isolated to possibly scattered showers and thunderstorms may develop in the highway 20 corridor during the late afternoon hours.
300 PM CDT MON SEP 5 2016 WV imagery shows the upper ridge anchored over AR/LA/MS, w/a longwave trough over the wrn CONUS.
This afternoon a cold front extends across the northern Plains into extreme northwestern Kansas. /Canadian border will send this cold front toward the area. Tomorrow night another upper level trough will move from the northern Rockies into the northern High Plains. This will allow the cold front to again make a push towards the area after being stalled during the day Tuesday.
/Issued 348 AM EDT MON SEP 5 2016/ High pressure will continue across the CWFA through the entire short term period. The trough/upper low associated with Hermine will continue to push off the east coast. Meanwhile, a high pressure center currently located across the central Gulf States will build eastward. At the surface, high pressure will continue to build down from the north on the back side of Hermine.
110 PM EDT MON SEP 5 2016 Upper level ridge continues overhead and keeps the area mostly dry for the next few days.
A deep layer cold front is fast approaching South Central TX with some sharp temperature drops of 30 to 35 degrees noted over a 1-2 hour period over NW TX. With the sharp falls in temperature, it is reasonable to follow the more aggressive model trends to see freezing temperatures reach the Nrn Hill Country by around 10 pm.
201 PM CST Sat Dec 17 2016 19Z surface obs show the the arctic high continuing to build south with the center of the ridge over the western Dakotas. Aloft, 19Z water vapor indicates a broad longwave trough over the U. Models show some energy moving across the state Sunday within the longwave trough aloft. Don't expected much of a warm up Sunday with the high sitting over eastern KS.
Forecast highs today will generally be in the lower to mid 50s.
Winds will be from the west to southwest and with the low temps should reach wind chill warning criteria.
334 PM EST Sat Dec 17 2016 A warm front will approach from the south this evening and tonight as a strong cold front approaches from the west.
1122 AM CST Sat Dec 17 2016 Arctic high pressure continues to build southeast into the region with a good push of clearing and bitterly cold temps moving in. Inserted these features into the grids as well as cold northwest flow off the relatively warmer waters continue to bring cloud streamers into the afternoon.
The upper trough exiting into western Colorado at time will leave a cold north-northwest across Utah through much of the weekend. For today lingering instability showers behind the exiting upper level trough will mainly hug the mountains of central/northern Utah through around mid-afternoon.
Surface analysis this morning places a warm front across Southern Missouri and Southern Illinois while a trailing cold front is located across Oklahoma and the Texas Panhandle. A tight pressure gradient across the Lower Mississippi Valley and 925 mb low level jet around 50 kts is producing breezy conditions across the forecast area. The aforementioned cold front will begin to move across Arkansas mainly this afternoon into tonight. An arctic airmass building in behind the front will result in precipitation gradually transitioning to freezing rain or freezing drizzle as the bulk of precipitation departs the Mid- South. In addition, area soil temperatures remain above freezing at many locations which should limit winter hazards to mainly elevated surfaces such as overpasses.
A very sharp cold front is quickly pushing south across North Texas and Arkansas. Texas is home to a plethora of extremes this afternoon with the front draped across the state, temperatures in the low 90s in the deep south, single digits and snow in the panhandle, and blowing dust with winds gusting near 50mph out west along the front.
Expect cold overnight low temperatures with single digits to teens across much of the high country. The upper level trough has moved well into New Mexico with a drier northwesterly flow filtering into Arizona. Expect the cold temperatures to continue through the weekend, particularly noticeable during the overnight hours when lows will drop into the single digits to teens across much of the high country.
Cold night in store for all of southeast Arizona with most areas seeing freezing temperatures Sunday morning.
The highlights in the short term will be dangerous wind chills spreading across the region by this morning.
Predawn water vapor loop depicted a positively-tilted upper trough axis from the MT/ND border across central WY, UT and northern AZ. Tight pressure gradient between this high and the front to the south continued to generate blustery northerly winds of 20 to 35 mph, resulting in bitterly cold wind chills of -15 to -35 degrees. 00Z short range models in good agreement with the eastward progression of the upper trough today and prevailing northwest flow aloft. The axis of the coldest air slides east into the high plains tonight with lows from -10 to -25 degrees. Areas west of the Laramie Range outside the higher mountains can expect wind chills of -15 to -30 degrees this evening before temperatures slowly rise later tonight. Expect high temperatures in the low to mid teens west and upper teens to lower 20s east.
222 PM EST Sat Dec 17 2016 Mainly light freezing drizzle rain mixing with and changing to light snow this evening will continue to create slick travel conditions on untreated roads.
1155 AM EST Sat Dec 17 2016 Observations running about 4-5 degrees cooler than grids this morning. Chattanooga Airport, TN 58 43 48 26 / 70 80 90 10 Knoxville McGhee Tyson Airport, TN 57 43 48 26 / 50 80 100 10 Oak Ridge, TN 57 40 45 25 / 50 80 100 10 Tri Cities Airport, TN 56 46 51 25 / 40 60 90 20 TN.
Persistent freezing drizzle that has been ongoing since late yesterday afternoon has finally come to an end across much of the KILX CWA as evidenced by improving visibilities over the past couple of hours. As temperatures fall below freezing, a light accumulation of ice of less than one-tenth of an inch is likely across this area. Arctic high pressure will be centered across central Illinois Sunday night bringing another bitterly cold night with lows several degrees below guidance, especially across our northern counties where an inch or two of fresh snow will be present. With the ridge axis situated right across the forecast area, winds will be light so the wind chills shouldn't be an issue, at least compared to what we will have over our area Sunday.
415 PM CST Sat Dec 17 2016 Warm and cloudy conditions will be in place ahead of a cold front that will approach the forecast area tonight. Timing on the line of showers and storms/cold front still looks to mainly effect the forecast area after midnight. We will be waiting for the cold front to be the trigger since soundings still show an inversion out in the warm sector of this system.
This flow looks typically string enough on the model BL winds to produce a blowing snow threat along the Buffalo Ridge in southwest MN, and will add.
The flow aloft backs from zonal to southwest as the upper trough over the western states deepens to the southwest. A cold front approaches the Florida panhandle but slows over the western part of the state as the push of high pressure behind the front weakens on Sunday.
Unfortunately, a cold front lies just to the NE of the CWA, waiting to plunge temps later this afternoon.
/Issued 359 AM EST Sat Dec 17 2016/ Early this morning what is left of a sub-freezing lingering classical CAD wedge in our far NE CWA should continue to warm above the freezing mark near sunrise or shortly thereafter. Have therefore planned to allow current Special Weather Statement for isolated freezing rain or drizzle to expire. Nam 295 K theta sfc does indicate some increased upglide ramping up after 12z today so continued high chance pops to likely for light rain or showers mainly north of the Atlanta metro area today with mostly cloudy skies elsewhere given the low level moisture present but lacking forcing mechanism. The cold front impacting the outlook area this weekend is expected to stall across portions of central/south central Georgia by late Sunday.
High pressure continues to build southward across the central Plains and settles in across northern Nebraska by evening.
Thus, a non diurnal temperature curve is expected with the highest temperatures already observed. The winter weather advisory mentions snow amounts, blowing snow, and the low wind chills for today and tomorrow. Since start out cold in the first place, think a cooler solution is the way to go. A strong arctic front extending from northeast Arkansas into northern Texas will continue moving south, and arctic high pressure will build into western Kansas. A vigorous upper level trough that was in northern New Mexico at 18Z will move rapidly across western Kansas and should extend from northern Missouri into central Oklahoma by midnight.
A strong arctic cold front will be the focus of afternoon and evening thunderstorms across area terminals. /issued 1210 PM CST Sat Dec 17 2016/ Surface analysis indicates strong cold front just now beginning to enter far northern McCurtain County at the noon hour with warm and moist air mass south of the front across our CWA. Lake wind advisory remains in effect through early Sunday evening as strong southerly winds will continue to veer later this afternoon and tonight with gusty northwest winds quickly following in the wake of the cold front.
/00Z TAFS/ A strong cold front currently stretching from JCT to TPL just north of BMQ will continue to progress southeast this evening. A deep layer cold front is fast approaching South Central TX with some sharp temperature drops of 30 to 35 degrees noted over a 1-2 hour period over NW TX. With the sharp falls in temperature, it is reasonable to follow the more aggressive model trends to see freezing temperatures reach the Nrn Hill Country by around 10 pm.
Temperatures will eventually wane past sundown but are maxing out in the low 80s along the immediate east coast to mid 80s inland. Similar conditions are on tap for tomorrow as upper level high pressure dominates the weather pattern.
1052 AM CST Sat Dec 17 2016 Cold front has just about cleared the entire forecast area at this time, and will see falling temperatures at all locations the rest of today. There has been some patchy very light drizzle or freezing drizzle around, and this may continue for another hour or two. Recent visibility trends suggest a diminishing drizzle/freezing drizzle threat and little or no impacts are expected from freezing drizzle.
Highs well below normal today, with areas of frost in the valleys and low deserts and below freezing temperatures in the high desert tonight. WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO At 9 AM PST, water vapor satellite imagery displayed an upper- level trough stretching from New Mexico into the Great Lakes Region, and dry northwest flow aloft across CA.
242 PM EST Sat Dec 17 2016 Strong cold front pushes through later tonight and Sunday with heavy rain. High pressure through mid week. Numerous showers and strong gusty winds are expected ahead of an approaching cold front. Although the high resolution models are faster with the onset of pcpn when compared with the synoptic models, all agree in pcpn amounts of 1 to 2 inches.
Model guidance suggests widespread freezing temperatures across the San Joaquin Valley overnight tonight, with many of the typically coldest locations falling below 28 degrees for a couple of hours during early Sunday morning.
Arctic high pressure moves out of Montana and into the central Plains tonight.
Overnight, much of eastern Utah and western Colorado will see clearing skies with winds diminishing in all but the highest elevations. While minimum temperatures have been adjusted downward, some uncertainty still exists on exactly how cold areas north of I-70 will get as clouds associated with the axis of a subtle 500mb trough pass the CO/UT border around 6am Sunday. By Sunday morning there may be enough weak forcing/upslope flow to squeeze a few snow showers out of this trough in the far northern Colorado Mountains, including the Elkheads and Park Ranges. As the trough flattens and heads east, clearing skies are expected by Sunday evening.
Upper level ridge centered offshore with northwest flow aloft today.
Given the strong surface pressure rises behind the accelerating front, leaning toward the higher end guidance with wind speeds tonight. Temperatures will plummet overnight into the teens across our northern and central counties, to the lower 20s along the I-10 corridor, by daybreak Sunday.
As for wind chills expecting a bit stronger winds either side of the valley with lows generally -25 to -30 with locally warmer/colder readings.
As for tonight, thinking really has changed very little as the bulk of the rain and storms will be behind the first push of the cold front. At this time, most of the precipitation should fall as rain with temperatures just above freezing in Marion, Winston, and Lamar counties. There could be a few cooler spots that hit freezing so we can not rule out an hour or two of freezing rain in those counties, but this should not be prolonged and little impact as surface and soil temperatures are well above freezing during this time, even if the air temperature at at or just below. 16 Sunday Night through Saturday The cold front continues to move southeastward through the area on Sunday, and exits Central AL Sunday evening.
200 PM EST Sat Dec 17 2016 Above normal temperatures are expected into Sunday with ridge along the coast and south low level flow. A cold front will cross the region late Sunday and cold air damming will again develop.
The upper level trough axis is quickly moving toward the New Mexico border this morning with most of the shower activity moving east of the state as well. No significant precipitation is expected for most of this time, as an elongated trough remains over the area, but without producing significant upper level support. By midweek zonal flow and stable conditions will move back into the region as the elongated trough finally separates as a closed low off the coast of Baja California.
1024 AM CST Sat Dec 17 2016 Arctic high pressure continues to build southeast into the region with a good push of clearing and bitterly cold temps moving in. Inserted these features into the grids as well as cold northwest flow off the relatively warmer waters continue to bring cloud streamers into the afternoon.
giving way to highs stretching into the lower to mid 20s. The upper trough impacting the region this weekend continues to move east of the area Sunday night, and west northwest flow forms aloft.
/Issued 256 PM CST Sat Dec 17 2016/ Arctic cold front has cleared the the Tulsa CWA with temperatures plummeting through the twenties across portions of northeast Oklahoma. Freezing drizzle has developed this afternoon across portions of northwest Arkansas and northeast Oklahoma, therefore the Winter Weather Advisory start time was moved up slightly. The freezing drizzle will give way to light snow across northeast Oklahoma and Northwest Arkansas late this afternoon through the evening hours as a band of snow to the west sweeps across the region.
117 PM EST Sat Dec 17 2016 A warm front will approach from the south tonight and Sunday morning, as a strong cold front approaches from the west.
249 PM MST Sat Dec 17 2016 Now transitioning from moderate deep layer QG ascent with the upper trough to moderate downward qg forcing with post trough northwest flow and mid-level WAA. Formation of this mtn wave with increasing mtn top stability late tonight will strengthen wly ridgetop winds with speeds above timberline peaking in the 40-50mph range Sunday morning.
1014 AM PST Sat Dec 17 2016 Freezing temperatures in the Valley this weekend with dry conditions. Northerly winds over the north end of the valley and parts of the west side of the valley may help to keep temperatures closer to the freezing mark so only wind sheltered areas would be susceptible to a hard freeze.
A strong cold front will push through the region this afternoon/early evening, with winds veering around to the north in its wake. Unfortunately, a cold front lies just to the NE of the CWA, waiting to plunge temps later this afternoon.
Freezing temperatures are also expected at KAUS/KSAT airports Sunday morning.
703 PM EST Sat Dec 17 2016 Another arctic cold front will push east across the area tonight.
The coldest temperatures will come with the lightest winds as the high pressure moves over.
655 PM EST Sat Dec 17 2016 High pressure to the northeast, and a fairly tight pressure gradient over the region, will keep the wind out of the southeast through the TAF period. Temperatures will eventually wane past sundown but are maxing out in the low 80s along the immediate east coast to mid 80s inland. Similar conditions are on tap for tomorrow as upper level high pressure dominates the weather pattern.
1010 AM MST Sat Dec 17 2016 Upper trough is now crossing the north central CONUS into the Great Basin with the main axis across the CWA. Strong upper ridging has set up across the Pac NW. Arctic high pressure now sits across the northern plains with the center over eastern MT into northeast WY. The center of the high will move east/southeast Sunday with return flow/warm air advection setting up. Arctic trough will break down in the period with active fast westerly flow.
644 PM EST Sat Dec 17 2016 A warm front will approach from the south this evening and tonight as a strong cold front approaches from the west.
Building high pressure will maintain dry weather and also cause temperatures to increase a degree or two the next few days.
There will be a brief period of snow showers across the local area as a cold front pushes through the region. Again, main concerns will be the low ceilings today, and any visibility restrictions from the snowfall, which will result in IFR/MVFR through last this afternoon. /Issued 354 AM CST Sat Dec 17 2016/ An arctic cold front is slowly pushing south and west across the southern and southwestern Texas Panhandle and extends at 0930Z from between Wellington and Memphis to Amarillo and then to near Nara Visa New Mexico. Considerable low clouds are quickly moving in behind the cold front with some patchy fog being reported at KDHT. Cannot rule out some light freezing drizzle across the Oklahoma and northern Texas Panhandles early before snow develops by around mid to late morning.
H-triple-R has a line of strong convection developing by 22z along the Ohio River down into northeastern Arkansas and it will move eastward and jell with the convection here in Middle Tennessee producing locally heavy rainfall with a few storms producing damaging winds first over western areas and then gradually progress eastward tonight ahead of the cold front. Cold front will move into far northwest Middle Tennessee around 9 pm followed by sharply colder temperatures and progress eastward and into the Nashville area by midnight and onto the plateau by daybreak. In behind the front in addition to the sharply colder temperatures look for a change over to freezing rain in northwest Middle Tennessee from midnight to 6 am Sunday and over eastern and southern areas Sunday morning.
Early visible satellite photographs show skies are partly cloudy while local radars are detecting only isolated showers with the majority being found on the distant waters beyond 20 nm south of the Lower Keys. Surface wise, a large western Atlantic ridge extends across the central portion of the Florida peninsula. Plenty of insolation within an east to southeast wind will allow high temperatures to climb into the lower to mid 80s.
TFJ Arctic high pressure over eastern Montana with clear skies and very cold temperatures this morning. Little wind under the high but with temperatures in the 20s below zero, wind chills are flirting with minus 40 in many locations. High pressure moves off to the east today with warmer air slowly spilling east of the divide.
giving way to highs stretching into the lower to mid 20s.
251 PM CST Sat Dec 17 2016 Active weather over the 18 hours across the Midsouth, with severe storms this afternoon and evening followed by possible light freezing precipitation late tonight. This will be the strongest Arctic cold frontal passage of the season thus far. 12Z NAM/GFS and later HRRR/RUC models show rainfall ending around the time surface temps fall below freezing. A Winter Weather Advisory was issued earlier for locations where there is most likely to be subfreezing temps overlapping with light rain. The center of the 1041mb Arctic surface pressure ridge will lift from the Kansas City area midafternoon Sunday, eastward along the I-70 corridor.
Thus, a non diurnal temperature curve is expected with the highest temperatures already observed. The winter weather advisory mentions snow amounts, blowing snow, and the low wind chills for today and tomorrow. Since start out cold in the first place, think a cooler solution is the way to go.
High pressure aloft will center to the west of Utah early in the upcoming week.
A positively tilted upper level trough over the northern Plains and Rockies will swing eastward tonight, pushing a cold front into the Ohio, Tennessee, and lower Mississippi valleys overnight.
530 PM CST Sat Dec 17 2016 Much talked about cold front as of 00z was located near a TYR. SSW winds ahead of the cold front continue to be sustained near 15kts with gusts as high as 25kts across some terminal locations. Pre cold frontal ceilings are mostly VFR with heights ranging from 4-6kft but directly behind the front. /issued 421 PM CST Sat Dec 17 2016/ Arctic cold front continues to bear down on the region with I-30 in sight as of 22Z this afternoon. The temperature gradient is quite stark on either side of the boundary with freezing temps just northwest of the DFW metroplex while readings ahead of the front are in the mid 70s to near 80 degrees over much of our CWA.
330 PM MST Sat Dec 17 2016 Current surface analysis shows arctic high pressure centered over western ND. Lows tonight across northeast WY and much of far western SD will likely be in the late evening, with steady or slowly rising temperatures after midnight, as arctic high moves east of the area and west- southwest winds start to bring warmer air and some clouds into the area.
256 PM CST Sat Dec 17 2016 Arctic cold front has cleared the the Tulsa CWA with temperatures plummeting through the twenties across portions of northeast Oklahoma. Freezing drizzle has developed this afternoon across portions of northwest Arkansas and northeast Oklahoma, therefore the Winter Weather Advisory start time was moved up slightly. The freezing drizzle will give way to light snow across northeast Oklahoma and Northwest Arkansas late this afternoon through the evening hours as a band of snow to the west sweeps across the region.
Gradient winds and aforementioned LLJ lead to a continuation of the high wind advisory over the Smoky Mountains of East TN. Elsewhere in that area, mix of trace freezing rain, sleet, and snow flurries by afternoon could leave a dusting of snow on elevated areas and on grassy surfaces.
Furthermore, the low temperature at the Marathon airport was only 78 degrees which is higher than the average low temperature in Key west. Surface wise, a massive western Atlantic ridge axis extends across the south central portion of the Sunshine State. Above normal temperatures (7-10 degrees) with daytime highs averaging in the lower to mid 80s and overnight lows in mid to upper 70s can be expected.