Aikyam-Lab/Synoptic-Bench huggingface dataset:
424 AM MST Sun Dec 13 2020 Current surface analysis shows low pressure over northeast NM, with an inverted trough stretching north from the low across eastern CO into eastern WY. To the north, low pressure is located across central Canada, with a cold front stretching south- southeast into western ND and MT. Cold front to the north will sink south through the area this morning and early afternoon, likely stalling out from northeast WY to northern NE later today and tonight. Highs today and Monday will range from the 20s across northeast WY, the Black Hills, and northwest SD to the low to mid 30s across southwest and south central SD.
Clipper passing to our north, and its attendant cold front sliding through our forecast area, will have some impact, as we should see deeper mixing in post-frontal west-northwest flow. As a result, will keep diurnal temperature range the smallest across the northeast, where readings may again struggle to reach 30, with highs a few degrees warmer into the lower-mid 30s through the Missouri River Valley.
Upper-level water vapor imagery shows a trough over the southern Rockies with a shield of stratus across much of the Plains and into the Mississippi Valley. High pressure remains in control for Monday with sunny skies in the morning giving way to afternoon clouds. Highs will be a few degrees warmer than we will see today, in the low 40s.
A cold front will sweep through the region later today with thunderstorms and low ceilings expected from mid day into early evening. Cold front will sweep through the area this evening and believe precipitation threat will end by 06Z. Cooler drier weather is forecasted for late tonight through Monday.
321 AM MST Sun Dec 13 2020 Currently, an upper level low continues to dig down into northern NM while latest WV imagery shows drying over the CWA since midnight as the system that brought light to moderate snowfall last night continues to move out of the area. High pressure will build into NW CO today tightening pressure gradients across the region. Upper level flow remains elevated west of the Laramie Range through 15z Monday ahead of an approaching trough.
- Light lake effect snow showers/flurries Monday A cold front will move through during the early morning hours Monday. Enough dry air should move in later today to break up the low clouds for awhile during the late afternoon into the evening. Then a cold front will come through before sunrise and bring some light snow showers to TAF sites near and west of US-131, otherwise the MVFR cigs will return after 06z tonight. A brief lull in winds/wave heights is then forecast before winds and waves ramp up again behind a cold front late tonight into Monday.
Surface temperatures will likely fall to near or just above freezing in the heavier snow bands and roads will likely become slick and hazardous due to slushy conditions. Still expect 2 to 4 inches of snow across northeast Oklahoma with the higher amounts occurring west of Tulsa and in the higher terrain areas of northwest Arkansas where 3 to 5 inches will be possible. Roads may remain slick in spots overnight as precip refreezes, especially on any untreated bridges or overpasses.
626 AM CST Sun Dec 13 2020 For the ArkLaTex terminals, VFR conditions will continue into the early aftn as an upper low moves down the Red River into our area. Cigs and vsby will deteriorate down to MVFR/IFR with even brief VLIFR as the cold front arrives shifts winds and chills the air. Our winds are ENE 5-10 mph and will back to NW later in the afternoon with the cold front.
Latest surface analysis indicated low pressure northeast of the Great Lakes, while weak ridging stretched from the northern Plains down into the mid Mississippi Valley. Quiet weather today as the ridge expands over the Midwest. With expected cloud cover, trended highs towards cooler guidance in the mid to upper 30s. This evening, the southern stream wave shifts east into the lower Mississippi Valley, focusing most precip well south of the area. Quiet and cool weather is on tap for Monday, when a Canadian ridge axis shift southeast towards the area.
349 AM CST Sun Dec 13 2020 After taking its sweet time moving across the area, cold front has finally cleared our eastern counties. North of the low track, a large stratiform rain shield will rapidly spread across the entire area this evening and overnight, before quickly ending from west to east Monday morning. Although thermodynamic profiles will be too warm for snow most of the event, increasing CAA after the upper trough axis pushes east of the cwa may be just enough for brief wintry mischief prior to precip ending. Note that with temperatures expected to remain above freezing, warm ground, and elevated surfaces mild/wet from the rainfall overnight, any snow that falls will have trouble accumulating and likely be limited to grassy areas or elevated surfaces, with little impacts.
420 AM MST Sun Dec 13 2020 Closed low continues to drop southeast into northeast New Mexico early this morning. As the low pulls further away from Colorado, the very light snow left across the southern portions of our county warning area will end by 5 am. High pressure will build across Colorado this morning with a dry and subsident airmass. Temperatures will be warmer tonight in and along the foothills with breezy conditions and increasing cloud cover.
302 AM MST Sun Dec 13 2020 Current surface analysis shows low pressure over northeast NM, with an inverted trough stretching north from the low across eastern CO into eastern WY. To the north, low pressure is located across central Canada, with a cold front stretching south- southeast into western ND and MT. Cold front to the north will sink south through the area this morning and early afternoon, likely stalling out from northeast WY to northern NE later today and tonight. Highs today and Monday will range from the 20s across northeast WY, the Black Hills, and northwest SD to the low to mid 30s across southwest and south central SD.
The upper level low and it's associated deformation zone will slide east southeast through the day today. The low circulation is expected to move across the southern Texas Panhandle this morning and will be north of Dallas by later this afternoon. We are expecting the deformation zone to continue to move southward along the northeast quadrant of the upper low.
while the global models are warmer and really do not show much in the way of snow. We would have to get some evaporational cooling to help nudge the thermal profiles cooler to be in a better situation for snow.
After taking its sweet time moving across the area, cold front has finally cleared our eastern counties. North of the low track, a large stratiform rain shield will rapidly spread across the entire area this evening and overnight, before quickly ending from west to east Monday morning. Although thermodynamic profiles will be too warm for snow most of the event, increasing CAA after the upper trough axis pushes east of the cwa may be just enough for brief wintry mischief prior to precip ending. Note that with temperatures expected to remain above freezing, warm ground, and elevated surfaces mild/wet from the rainfall overnight, any snow that falls will have trouble accumulating and likely be limited to grassy areas or elevated surfaces, with little impacts.
The first of these glancing system will come today as a upper level trough will move out of New Mexico and into the Red River Valley before moving further east into the Ozarks. High pressure will build into the area tonight clearing skies out and allowing temperatures to drop into the low to mid 20s. High pressure will remain in control over the area Monday providing sunny skies however weak mixing will keep highs in the mid 30s to lower 40s.
252 AM MST Sun Dec 13 2020 A cold front that is dropping through northeast Montana has produced some light snow across northern Carter and Fallon counties. By early morning, this snow activity will move into the lower elevations near the the mountains like Livingston and Big Timber. Reimer A splitting trough moves through the area Monday and this will provide an opportunity for another round of snow.
320 PM EST Sun Dec 13 2020 Synopsis/Discussion/Marine/Hydro -- Cold with light lake effect snow on Monday -- -- More quiet/mostly dry weather this week -- -- Cold with light lake effect snow on Monday -- Nrn stream trough dips south into the nrn GrtLks Rgn late tonight into Monday which drives a sfc cold front through.
307 PM EST Sun Dec 13 2020 A low pressure system moving through the Tennessee Valley will bring a chance of precipitation to parts of the region tonight.
We will see a trailing cold front from the low swing across tonight and shift winds to the northwest.
Little change in 12Z forecast models showing a widespread light to moderate snowfall through Monday morning with the highest totals over northeast Harney and n-central Malheur county and higher terrain south of the Snake Plain.
Currently, an upper level low continues to dig down into northern NM while latest WV imagery shows drying over the CWA since midnight as the system that brought light to moderate snowfall last night continues to move out of the area. High pressure will build into NW CO today tightening pressure gradients across the region. Upper level flow remains elevated west of the Laramie Range through 15z Monday ahead of an approaching trough.
That said, temperatures in the low to mid-20s by mid-afternoon are only about 5 degrees below normal, and will only feel exceptionally cold because of recent warmth.
Two recent ACARS soundings at KTUL sampled a deep isothermal layer near freezing with a minor warm nose around 900mb. Accumulations will occur with this type of snow however preceding wet ground and temps hovering around freezing will allow for some melting.
1005 AM EST Sun Dec 13 2020 High pressure centered over the Florida peninsula has allowed for very light winds over the peninsula this morning. High pressure centered over Florida will produce light winds less than 10 knots over the eastern gulf waters today. A cold front will then move through the waters and stall just to the south on Monday with weak high pressure building in behind it.
(This evening through Monday) As the upper level low tracks across the northern Big Country this afternoon, a few light showers will continue to be possible across the Big Country. Expect morning lows in the low to mid 20s for most locations, with the coldest readings in low lying areas and river valleys. Plentiful sunshine should allow temperatures to warm into the low to mid 50s Monday afternoon.
1119 AM EST Sun Dec 13 2020 A strong 500 mb ridge axis currently extends from near Cancun to the southeast Bahamas. The mid-level ridge will hold strong until Monday night, then it will settle deeper into the Caribbean.
1022 AM MST Sun Dec 13 2020 Currently, an upper level low continues to dig down into northern NM while latest WV imagery shows drying over the CWA since midnight as the system that brought light to moderate snowfall last night continues to move out of the area. High pressure will build into NW CO today tightening pressure gradients across the region. Upper level flow remains elevated west of the Laramie Range through 15z Monday ahead of an approaching trough.
Convection will gradually begin diminish across our western terminals later this evening as the supporting upper level trough pivots farther east with our eastern sites likely seeing showers ending after midnight through daybreak on Monday morning. Look for this activity to continue increasing in coverage and intensity as we go into the early afternoon with the upper level trough beginning to pivot eastward from the TX panhandle across the middle Red River Valley.
Much of the winter storm warning area performed well, with the highest amounts of 12-14 inches reported from Plains to Meade. Based on latest radar trends and short-fuse models, ongoing widespread light to moderate snow is expected to begin dissipating west to east generally after 13-15Z, and exiting the area by early afternoon as a closed upper low in the southern Texas Panhandle shifts east into the Ark-La-Tex Region by late afternoon. A dry/tranquil pattern returns to western Kansas tonight as ridging aloft transitions out of the Colorado Rockies into the adjacent Western High Plains while much drier air in the lower levels spreads into western Kansas within a west-northwesterly downslope flow. Cold and dry conditions will prevail Monday as weak ridging aloft continues to transition eastward through the Central Plains.
Temperatures are roughly 10 degrees cooler compared to 24 hours ago in the wake of a weather system that grazed the northeast corner of our forecast area yesterday. This causes our temperatures to pulse up and down with each passing trough, but precipitation is hard to come by.
Overnight into Monday: HRRR and some other guidance is slower to clear shallow stratus out tonight, and hedged a little bit that way with the forecast, a bit warmer and cloudy/mostly cloudy.
1029 AM MST Sun Dec 13 2020 Current surface analysis shows low pressure over northeast NM, with an inverted trough stretching north from the low across eastern CO into eastern WY. To the north, low pressure is located across central Canada, with a cold front stretching south- southeast into western ND and MT. Cold front to the north will sink south through the area this morning and early afternoon, likely stalling out from northeast WY to northern NE later today and tonight. Highs today and Monday will range from the 20s across northeast WY, the Black Hills, and northwest SD to the low to mid 30s across southwest and south central SD.
152 PM CST Sun Dec 13 2020 A cold front has influenced much of today's weather across the area with light snow and gusty 25 to 35 plus mph northwesterly winds, and will continue to do so into tonight with much cooler temperatures due to the strong CAA. Post-frontal, drier northwesterly air has scoured out the majority of the low-level cloud cover, and much of the area will be mostly clear tonight as high pressure noses in from the northwest. Cloud cover returns on Monday in response to a developing low pressure center across Wyoming. This system will slide southeasterly and, in combination with high pressure to the northwest, lead to southeasterly afternoon breezes across the CWA, strongest in central South Dakota with gusts of 20 to 30 mph.
A strong cold front will bring showers late tonight and Monday.
- Light lake effect snow showers/flurries Monday A cold front will move through during the early morning hours Monday. MVFR ceilings will continue, and chances for light snow will return early Monday morning as a cold front sweeps through. A brief lull in winds/wave heights is then forecast before winds and waves ramp up again behind a cold front late tonight into Monday.
1131 AM CST Sun Dec 13 2020 Water vapor satellite this morning shows a short wave trough dropping out of Saskatchewan. A cold front will sweep east across the area with the short wave trough but the frontogenesis in the baroclinic zone looks to be almost non-existent. Both the GFS and NAM MOS are 3 to 5F warmer than the NBM in this area.
952 AM CST Sun Dec 13 2020 Light snow from this morning's cold frontal passage is still lingering across southeastern portions of the CWA this morning. Current surface analysis places low over Manitoba with cold front dropping to the southwest, working through northwest North Dakota. With cooler air pouring in behind the system, do not expect much if any rise in temperatures today, so have trimmed back on highs a bit.
211 PM EST Sun Dec 13 2020 An advancing low pressure system will bring significant snow to the ridges of West Virgina early tomorrow morning. A weak cold front will continue southeast of Pittsburgh this evening. A new low pressure system, currently in ArkLaMs, will track through the Ohio River Valley after midnight. With strong upper-level forcing centered over the ridges of WV, mainly eastern Tucker County, heavy snow will likely accumulate in a short amount of time. As the low quickly tracks east and drier conditions prevail under NW flow, weather will improve in the ridges of West Virginia. Building high pressure late Monday will cease any lingering precip.
1049 AM MST Sun Dec 13 2020 High pressure aloft will shift east across the region today ahead of the next storm system scheduled to arrive for late tonight through Monday. This storm will bring another round of snow to High pressure will return midweek, with a new storm possible for late in the week.
Further south the transition to predominant snow will take awhile longer however upstream observations suggest the band of snow within the mid level trough axis is maintaining sufficient intensity that a burst of measurable snow will overspread SE OK through west central AR this evening with travel impacts possible.
Strong inversions up north will support fog and or low stratus this morning along the highway 40 corridor. Today a ridge aloft builds over the region allowing midlevel temperatures to begin warming. This will really only influence the higher elevations as the valleys will have decent inversions in place from the new snow pack and cold push. The next low pressure will make landfall today in the Pacific Northwest and track over the Great Basin tonight. Therefore the weak warm air advection and clouds should result in warmer lows. By sunrise tomorrow the trough axis enters northeast Utah and pushes a cold front southeastward through the course of the day. Prefrontal winds out of the southwest will try to advect in moisture, but the low levels are rather dry so that could take a while to saturate especially in the lower valleys.
The cold front is exiting the CWA as it moves deeper into Minnesota. While satellite imagery isn't surprising, the low visibility is.
Further backing to the upper flow occurs Monday as the next upper level short wave trough moves over the Great Basin. The southwesterly flow aloft and falling heights will induce a lee trough across eastern New Mexico and enough of a pressure gradient to result in breezy south winds, especially up on the Caprock.
These winds and cooler temperatures will keep wind chills in the single digits to low teens. A cold front that is dropping through northeast Montana has produced some light snow across northern Carter and Fallon counties. By early morning, this snow activity will move into the lower elevations near the the mountains like Livingston and Big Timber. Reimer A splitting trough moves through the area Monday and this will provide an opportunity for another round of snow.
MORNING DISCUSSION: Synoptic Setup: Forecast begins with cold dry arctic air dropping down the front range and through the high plains of Montana this morning and spilling into the Dakotas. The trough behind this cold air runs northeast up into the center of the cold over Nunavut. To the west a relatively warm warm pacific Ridge is sitting just off the coast for the Pacific Northwest and British Columbia. Multiple trough/ridge couplets are lined up behind this ridge in the north Pacific. Today through tonight: With the left over wind from the cold frontal passage apparent temperatures have dropped just far enough to warrant a Wind Chill Advisory over northern Valley county this morning. High pressure and cold air will settle in tonight under an inversion making it the coldest night over the week.
Closed upper low over the plains today will open tonight and quickly move east. Upper trough axis is likely to advance to near the Plateau by sunrise Monday, then well east midday.
but still unfavorable flying conditions regardless with prevalent low cigs & vsbys associated w/ warm front edging inland. Cold front will be making its way across CLL terminal in a few hours and should make continued southward progress and off the coast prior to sunset. Expect a band of precip to consolidate along the wind shift as it approaches the Highway 59/I-69 corridor.
257 PM CST Sun Dec 13 2020 A few respectable bands of snow showers are continuing eastward across the Upper Mississippi Valley this afternoon ahead of a cold front pushing through western Minnesota. The cold front will progress across the remainder of the area by early this evening with gusty northwest winds and strong CAA developing behind it. Thermal troughing overhead Monday will make it difficult to reach 20 for a high. Here, temperatures may drop lower than currently forecast, but it will depend on the timing of the high and mid level clouds.
At the surface, a cold front was seen stretching from southwest Ontario, through northwest Minnesota and into the Dakotas. This should set the stage for a mostly sunny, but cooler day on Monday, with high temperatures generally in the 20s.
with a cold front extending south and moving through Florida on Monday morning bringing a chance of showers and slight chance of thunderstorms.
A trough associated with the next system featured rather strong winds aloft, generally above 100kt ~35Kft ASL to near the tropopause.
Skies are expected to clear on Monday, as high pressure drifts into the Great Lakes region.
On Monday, we'll be in southwest flow aloft ahead of an upper trough moving into the Rockies.
Otherwise, stratus refills in overnight before greater potential of clearing late in the period with arrival of stronger high pressure.
218 PM CST Sun Dec 13 2020 An upper level trough is currently over the OK/TX border moving due east and as a result of the trough sfc winds have hit wind advisory criteria across southeast New Mexico and the Permian Basin. A cold front recently moved through the area transporting cooler air into the area and kicked up a ton of dust temporarily dropping visibilities down to a mile at some locations. Monday's high temps, in the 50s area wide and the 60s for the Rio Grande, will struggle to climb as cold air transported from the cold front will linger.
The current track of the low for Monday's system has shifted farther north which will provide another shot of snow west of a line from Roundup to Biddle. Snow amounts in the lower elevations will range from a trace along the aforementioned line, increasing to up to 3 amounts towards Livingston. The track of this low could still change over the next 24 hours so we will update the forecast accordingly.
In addition, a few flurries could fall out of the lower cloud cover in this flow. The flow may become southwest as the high leaves perhaps bringing some increased clouds, especially to the southwest. An upper low will push into South Dakota Monday afternoon.
Winds will become southerly overnight and then southwest to northwest through the day as a cold front moves through the region. A cold front will move through the region Monday, with a chance for showers and a few thunderstorms.
302 PM MST Sun Dec 13 2020 A strong arctic high pressure is draped across southern Saskatchewan and northeastern Montana. Next round of snowfall on Monday will again be limited to the higher elevations of central and southern Montana.
Ridging aloft is occurring across the Rockies ahead of this system, which will translate eastward across the central CONUS tonight into Monday.
Surface winds are forecast to increase late Monday morning through the afternoon hours as the pressure gradient tightens in response to low pressure development over eastern New Mexico and eastern Colorado. High pressure sets in overnight and skies are expected to continue clearing. Between the breeze and snowfall keeping things cooler, highs will generally be in the 40s.
By afternoon, light to briefly moderate snow will move through the higher terrain. In the lower populated valleys, guidance still indicates a few hundredths of an inch of liquid, which will translate to around a coating to a half-inch of snow. With afternoon highs only reaching near freezing, some slick travel will exist across all of the western slope, including the lower valleys where winter-weather has been hard to come by so far this winter.