Aikyam-Lab/Synoptic-Bench huggingface dataset:
An upper level trough will dig into the Great Plains tonight as an closed low develops over South Dakota and Nebraska in the early morning hours. At the surface, a low pressure system and accompanying cold front will develop over the High Plains, moving southeast during the day. Light precipitation will begin early tomorrow morning as the cold front begins to enter northern Nebraska, then increase later in the day and evening as the air saturates. Given the temperature profile, precipitation will likely start off as rain with a mix of sleet or freezing drizzle, then transition to snow in the late afternoon as boundary layer temperatures cool sufficiently behind the front. Much cooler overnight temperatures are expected tomorrow night with lows in the low teens to single digits.
Decreasing clouds and lighter but more northerly winds are anticipated behind the system, dropping lows into the lower 30s. Tomorrow on the front side of the ridge, northerly winds will remain in place, providing light CAA. This will keep daytime highs moreso near normal in the lower 50s. Overcast skies will keep overnight lows a tad warmer, reaching the upper 30s.
Much cooler temperatures ahead before a rebound towards the second half of the weekend.
533 PM CST Thu Jan 13 2022 High pressure will keep skies mainly clear through the coming TAF period at all terminals. /ISSUED 222 PM CST Thu Jan 13 2022/ Clear skies prevail across the area with temperatures mainly in the lower 70s. Winds tonight will remain light and variable, but with slightly higher dewpoints, lows should be a few degrees warmer than last night. Highs tomorrow will be about 1-3 degrees warmer than today, or in the middle to upper 70s. A strong trough axis will pass through the Central Plains tomorrow and this will send our next cold front into the area Friday night.
As an upper trough in the Pac NW moves toward the Great Basin, expect winds to decrease further through the remainder of the afternoon. As the upper trough fills, it clips our southwest tonight, however, a clipper system will drop in from the north, bringing colder temperatures, gusty northwest winds and rain and snow showers to the area overnight into Friday. As such, best potential for snow accumulations is along the southern foothills and mountains, extending into the higher hills of the southeast. Gusty winds will return to the western foothills locations Friday night as high pressure builds back into the region.
Clear skies and light winds, coupled with the weak wave that moved through this afternoon should bring us temperatures around freezing in the morning. Surface and upper lows are following very similar trajectories and as we all know, this can be the difference in one area or another seeing more snow, less snow or a wintry mix. We're starting to advertise 4 to 6 inches, with the highest potential across our north and east, but honestly, it could be more than that in several spots, especially on the Plateau.
Recent water vapor imagery was showing an upper low entering the Pacific Northwest with widespread high-level moisture from southern California into the northern High Plains then spreading southeast as northwest flow remain largely in place.
709 PM EST Thu Jan 13 2022 Upper level ridging builds north across the Four Corners region from Mexico and a trough axis easing away from the southeast US coast continue into much of Fri. through Fri as Canadian high pressue ridges down to the Gulf of Mexico. High pressure building into the Gulf will keep robust northwest winds through early Fri. This high pressure tracks over and east of the state by Sat with winds diminishing and veering. Low pressure moving over the southeast US late Sat and Sun trails a cold front into the east Gulf and across FL.
A northeast to southwest orientated trough axis over Canada will interact with upper level low pressure over the Pacific northwest this evening through the day Friday. Friday morning could see additional freezing drizzle in far western North Dakota as the mid-levels dry out and the lower atmosphere remains briefly saturated. Any freezing drizzle that falls in the morning likely won't last more than a couple hours over any one area before either turning to light snow/flurries or drying out completely. Up to four inches is expected across the advisory area with more snow east and less snow, but better chances of freezing drizzle/rain, west.
High cloudiness continues to overspread the region ahead of the next Pacific system which will move across CO on Friday, merging with an upper trough dropping southward out of Canada and intensifying across the central plains. Given the enhanced westerly winds along with high cloud cover have gone warmer than model blends for lows tonight. Cold front will move across southern CO early Friday morning with the potential for an initial damaging wind gusts towards 10 AM according to high res models. Snow then spreads into the southeast mountains and Palmer Divide and Raton Ridges through the late morning and afternoon. With greater consensus on a more eastward closed low progression, degree of northeast upslope flow looks less and low levels appear to take more time to saturate.
12z model suite exhibits a bit of a shift west and south with the track of upper low and with support from ensemble members, have upped forecast snow amounts for a good portion of the forecast area. That said the heaviest totals of 2-4" remain focused over eastern sections of NW AR, but some higher amounts now showing up in the high terrain of SE OK as well. The low level thermal profiles still pose some questions, at least initially, during this event, but as the core of the upper low passes in a more favorable area, would expect dynamic cooling of the column enough for most areas to change over to snow by Sat afternoon and especially evening.
With temperatures around freezing there could be a little sleet before the temperatures warm enough to change to rain later in the morning and into mid afternoon.
500 PM MST Thu Jan 13 2022 Western CONUS ridge will remain in place over western NOAM as a stationary front wobbles over the region per several active impulses, supporting large temp fluctuations, some snow, and wind. LSA will begin to increase late tonight, with some light rain/freezing rain possible over the NE FA, where a strong warm nose will linger into the morning. The main round of LSA will shift across the area Friday morning right behind the sfc cold front (with temps falling through the day).
The highest snowfall totals will be along and west of the Minnesota River Valley. 50" across western Minnesota, so in addition there being ample moisture, WAA will also play a role in the higher snowfall totals across western Minnesota. Southwestern Minnesota looks to have the highest chance of seeing some Fgen forcing at play, which would also set the stage for higher totals. There has been little change in the guidance as far as the overall track of the low over the last 12 to 18 hours, so still feel confident in the highest amounts falling along and west of the Minnesota River Valley. Easterly winds will increase as the low tracks southward across South Dakota, but with gusts topping out around 20-25kts during the late afternoon, am not too concerned with widespread blowing snow.
Visible satellite imagery indicates high clouds spreading over Northern California this afternoon associated with a low pressure system currently impacting southern California. A southwesterly breeze is also starting to pick up over the Sierra crest and Southern Cascades associated with a low pressure system to our north. Ensemble guidance is in good agreement the low to our north will dig southeast tonight with a dry trough extending into the great basin.
Cooler and much drier air is overspreading EC FL. Deepening low pressure off the eastern seaboard and high pressure building into the Gulf of Mexico will tighten the pressure gradient across the local Atlantic waters.
Would not rule out drizzle/freezing drizzle this morning, but lack of forcing with a ridge overhead supports leaving chances out.
2) Scattered to widespread light to moderate snowfall across southeast Wyoming with the highest amounts being in the mountains and areas west of the Laramie Range.
Meantime, a ridge of high pressure will build through today with a very dry airmass moving into the area. On Saturday, morning lows should be slightly cooler. However, high pressure begins to move to the east and southerly winds will push a warmer and slightly more humid airmass by the afternoon.
Look for light northerly winds to advect in some cooler air overnight as temperatures fall back into the lower 30s in most locations by early Friday morning. Tomorrow on the front side of the ridge, northerly winds will remain in place, providing light CAA. This will keep daytime highs moreso near normal in the lower 50s. Overcast skies will keep overnight lows a tad warmer, reaching the upper 30s. Lows Saturday night will be above freezing, keeping precip as all liquid. This system in the water vapor view was an upper trough over southern British Columbia/Alberta, was moving to the SE in a predominate flow rounding a deep low over NE Canada. The disturbance and upper low will merge and intensify as they head SSE over the High Plains on Saturday.
1040 PM MST Thu Jan 13 2022 A closed low over the Pacific Northwest will slowly weaken as it drops southeast across the western states overnight. Warm advection and an increasing westerly gradient is expected ahead of this trough. High clouds will increase this afternoon with a lowering cloud deck expected across the north overnight as this trough approaches. Conditions will improve by tomorrow evening as this trough and associated front move southeast of the forecast area.
The upper-level flow will remain relatively cyclonic now through the weekend but, a ridge of high pressure over the northwestern Gulf of Mexico will build into the region by Saturday morning. Winds will gradually clock around at light to gentle speeds Friday night, becoming southeast Saturday afternoon, Southeast to south winds will once again freshen Saturday night as the next cold front sweeps into the Gulf of Mexico. In 1981, the low temperature in Key West was 41F. 3F, 2 whole degrees cooler than the previous record of 63.
- KC metro should expect to receive anywhere from 2 to 4 inches of snow Discussion: Unseasonably warm this afternoon with temperatures in the mid to upper 50s thanks to mid level ridging that has built in from the west.
1031 PM CST Thu Jan 13 2022 (The rest of tonight) Light winds will remain in place overnight as weak high pressure slides east.
1031 PM CST Thu Jan 13 2022 (This evening through Friday) Expect warm and dry conditions on Friday across the area due to low level west to southwest flow and a thermal ridge.
Isolated snow showers associated with a weak upper trough will continue until around midnight. As the trough moves out of the area late tonight, there will be enough breaks in the clouds for patchy valley fog and stratus to develop by early Friday morning. The inversion will strengthen on Friday as high pressure aloft builds in from the west. Generally VFR, but low stratus and valley fog will bring morning MVFR/IFR conditions as an upper ridge rebuilds into the area. A weak trough will pass through our area tonight. High pressure aloft will rebuild Friday, intensifying the inversion at lower elevations.
A cold front was shifting south across the region, with the resulting north winds pulling low cloud cover into central and east central WI. High pressure will build into the region this evening, with subsidence and dry air advection causing partial clearing to occur. Used a few meso-models to focus the highest pops and qpf over Kewaunee and southeast Door counties.
A surface cold front has cleared much of north-central MT, with a northwesterly wind shift and a five to ten degree temperature drop being the most noticeable changes so far. Otherwise, a cold front will move through the region from north to south this evening and tonight, bringing a north to northwesterly wind shift, some light snow, and the introduction of MVFR/IFR conditions, mostly for the north-central terminals. Current satellite imagery shows a clearing line on the higher clouds from Havre to Ennis, moving quickly eastward with a passing upper level ridge axis. Temperatures fall to the 20s for most areas tonight with much cooler temperatures (near seasonal mid-winter averages) in the 30s for most areas on Friday.
A surface cold front has cleared much of north-central MT, with a northwesterly wind shift and a five to ten degree temperature drop being the most noticeable changes so far. -RCG 1015 PM MST Thu Jan 13 2022 (14/06Z TAF period) A cold front continues to move south through the region this evening and overnight, bringing a north to northwesterly wind shift, some light snow, and the introduction of low VFR/MVFR/IFR conditions. Current satellite imagery shows a clearing line on the higher clouds from Havre to Ennis, moving quickly eastward with a passing upper level ridge axis. Temperatures fall to the 20s for most areas tonight with much cooler temperatures (near seasonal mid-winter averages) in the 30s for most areas on Friday.
A cold front is still expected to move across the Vegas valley tomorrow morning clearing skies and bringing in breezy northerly winds. A cutoff low well to our southwest and a second low pressure system over the PacNW have combined to draw abundant mid and high level moisture northward across our area today. While the cutoff low to our southwest meanders well off the coast on Friday, the upper low to our north dives southeastward through the Intermountain Region. It will also bring a cold front and gusty north winds into the area on Friday. Well above normal temperatures are forecast on Friday the cooler airmass behind the front returns temperatures closer to seasonal averages on Saturday.
This is important, as the fluffy snow north could add up to 2-5 inches, despite the lower qpf forecast, and the south is expecting 4-8 inches, despite rather high qpf around 0.
Wet bulb temps would be just below freezing after saturation. Freezing rain is possible in northeast Nebraska with just a shallow layer of cold air expected at the surface. Sleet and graupel may accompany the freezing rain while we await saturation.
1038 PM MST Thu Jan 13 2022 Western CONUS ridge will remain in place over western NOAM as a stationary front wobbles over the region per several active impulses, supporting large temp fluctuations, some snow, and wind. LSA will begin to increase late tonight, with some light rain/freezing rain possible over the NE FA, where a strong warm nose will linger into the morning. The main round of LSA will shift across the area Friday morning right behind the sfc cold front (with temps falling through the day).
Uncertainty still exists regarding the exact track of the system, which leads to lower confidence in where the highest snowfall totals will end up by the end of the event. A dry cold front that traversed the CWA during the day is now clear of the area to our south. Overnight weak high pressure will build into the region this evening, centered over the Mississippi River to our northeast. The western part of the area will likely see a longer rain/snow mix and warmer temperatures overall, which will limit accumulations, but the colder eastern CWA will likely see several inches of snow very late Friday through Saturday. Where exactly that band sets up may end up bringing snow totals in the eastern CWA near the high end of the forecasted range (or locally higher thanks to mesoscale forces at play).
Strong to high winds remain possible behind the front, with the highest winds occurring over northern Johnson County.
(The rest of tonight) Light winds will remain in place overnight as weak high pressure slides east.
Radar is showing some light showers in eastern KY that are moving SE, behind the exiting upper trough axis. CDG Chattanooga Airport, TN 33 50 35 49 35 / 10 0 0 40 90 Knoxville McGhee Tyson Airport, TN 33 47 32 46 33 / 10 0 0 30 80 Oak Ridge, TN 32 48 32 45 32 / 10 0 0 30 70 Tri Cities Airport, TN 32 43 28 41 28 / 30 10 0 20 60 NC.
Widespread measurable snowfall is then likely between Friday evening and Saturday afternoon, with the highest snowfall totals favoring west central Illinois. At the surface, an inverted trough will become more pronounced as it shifts southeastward across the Corn Belt. Thermal profiles support a quick changeover to snow just prior to 00z/6pm as precip rates begin to increase and temperatures wet- bulb below freezing.
Winds will begin light and variable thru Friday morning, then becoming out of the southeast into Friday afternoon ahead of an approaching cold front.
A ridge in the Rockies is continuing to bring northwest flow aloft to the central plains. Friday a strong cold front will move through western Kansas with good mixing behind the front we should see winds pick up quickly out of the northwest sustained at around 30 mph with gusts of 50 mph or greater by afternoon. Winds will continue to howl through the day on Saturday as the 850 mb winds on the backside of the low continue to stay strong and will have good mixing to the surface.
A low pressure system passing through the Four Corners will bring gusty winds Friday into Saturday with much cooler temperatures Saturday.
Highs today will be range from the low 50s to low 60s out ahead of the cold front. Temperatures will plummet behind the front with many areas being at or below freezing by midnight Saturday. Some models keep this round all rain, however, temps are only above freezing at the surface so with dynamics and wet bulb we may see this be more snow than rain.
245 AM EST Fri Jan 14 2022 Deep upper level low/trough slowly tracking through Eastern Canada today, with strong high pressure (1045 MB) building over Ontario.
Most of the Midsouth should stay above freezing again tonight.
405 AM EST Fri Jan 14 2022 Weak high pressure will move east across the region today as a cooler airmass settles into the area.
Throughout the day, upper trough is expected to dive southeast towards the Central and Southern Plains. Farther south, warm conveyor east of the low will lead to mild day with highs warming into the 50s south of the Missouri River. Cold front with the system is expected to crash southward through eastern Kansas into Missouri this evening leading to rain transitioning over to snow as near surface profile cools below freezing. Behind the cold front, north-northeast winds are expected to increase leading to patchy to areas of blowing snow.
At 430 AM, an upper level trough was diving southward through the Dakotas. Surface temperatures were above freezing south of Interstate 80 and below freezing north of Interstate 80. Through 10 AM this morning: Light freezing rain or drizzle will be possible through 10 AM this morning, especially along and north of Interstate 80. This presents a scenario where the lower layer of saturation could produce some patchy drizzle or the saturated layer above 5000 ft AGL could generate just enough precipitation to sneak through the warmer dry layer. Either event could produce light icing on area roads through 10 AM this morning (when temperatures should increase above freezing), especially with road temperatures hovering near 32 degrees. Expect highs to only be in the lower 20s Saturday.
A mix of freezing fog and low stratus will cause reduced visibility and spotty light freezing drizzle concerns this morning under a northerly flow. Brief high pressure ridging transitions through the Northern Rockies later today and tonight with stable atmospheric conditions, thus fog and stratus will be very slow to diminish later today. Another round of freezing fog is anticipated tonight into Saturday.
Despite the sunshine though temperatures will run below normal due to cool air advection with temperatures today expected to be a few degrees cooler than yesterday with highs only reaching into the mid to upper 60s north into central areas, and around 70 to the lower 70s far south during the afternoon, with northwest winds around 10 mph. Low pressure exiting east over the Atlantic and high pressure building in from the west will maintain northwest winds in the 15 to 20 knot range with seas of 3 to 5 feet over the southern and central near and offshore through early afternoon, before gradually diminishing and subsiding as the gradient relaxes during the afternoon. Despite the low humidity, low ERC's combined with sustained winds of less than 15 mph will preclude Red Flag conditions.
Impacts will be further limited by sfc temps just either side of freezing, but there's still a chance for a dusting late Friday night and Saturday morning west of Interstate 65. Areas farther north will stay closer to freezing through Sat afternoon, but will see a period of very light precip or none at all. Overall not expecting much impact through the day on Saturday, but even slightly cooler temperatures or better snow rates in the morning could warrant at least a Special Weather Statement, most likely in southern Indiana or our northern/western-most Kentucky counties.
Back to the west, some light freezing rain has developed through the northern James River Valley with soundings indicating a warm layer situated roughly from 750-900 mb over that area. We are still looking at increasing winds by late afternoon and evening in a tightening surface gradient on the back side of the exiting inverted trough.
A stronger low pressure system will dive southeastward from the central Plains this morning to the lower Mississippi Valley this evening. Slight warmer temperatures in the mid teens will be possible along the Lake Michigan shoreline.
The short term forecast focus is on the strong winds expected with the low pressure system moving across the region today through early Saturday. An upper trough dives south from the northern to the central high plains today as another short wave trough moving through the Intermountain west moves into the southern rockies and merges with the northern trough over the central plains overnight. The surface pressure gradient in the wake of the low maximizes across the forecast area between 18-00Z this afternoon. Blowing dust will be a possibility with gusts to 60mph, but confidence is low in any kind of widespread blowing dirt/dust event, so have only mentioned patchy blowing dust in the counties with the High Wind Warning.
The cold front will progress quickly through the CWA this morning, with strong and gusty northwest winds in its wake. Gusts of 50-55 mph will be possible over the high plains. The front retreats to the east as a warm front Saturday, with 700mb temperatures warming to near 0C, yielding highs in the 30s and 40s. A upper ridge then builds into the Northern Rockies and Plains through Saturday night.
This suggests a loss of ice aloft and the potential for some freezing drizzle. Some freezing rain has even been reported at the Williston airport, but given the lack of many returns on the Williston radar, this could be more of a freezing drizzle situation. As the low continues to propagate southeast, north winds will pick up through the morning and afternoon, especially across the south where we could see some gusts up to 45 mph (mainly south of Interstate 94). The flow starts to deamplify as broad ridging spreads out across the western CONUS on Saturday.
621 AM EST Fri Jan 14 2022 Weak high pressure will move east across the region today as a cooler airmass settles into the area.
A cold front will come racing through the Panhandles today. Also the base of the positively tilted trough will be moving across. On Saturday, north winds will likely stay up in the 25 to 35 mph range, especially across the southeast Texas Panhandle for much of the day as a strong upper level low moves southeast across eastern Oklahoma. Lowest relative humidity values will be generally in the lower to mid 20's.