Aikyam-Lab/Synoptic-Bench huggingface dataset:
Can't completely rule out a light flurry or two along the higher elevations of the upslope but better chances for a snow shower exist behidn the low on northwest flow. The moisture profile in the trough is similar late Thursday night and could be squeezed out in the weak caa between the low and the arctic high.
There is a chance that the band stays completely offshore until the low level winds turn more to the northeast later Thursday into Thursday night.
233 PM CST Wed Feb 2 2022 The TN Valley is in between a ridge off the Atlantic coast and an elongated trough out west. The anchored LLJ will finally slide eastward tonight, allowing for gusts to slack after sunset, however the tight gradient in place will keep winds elevated, especially in the higher terrain. A 50-60kt LLJ will slide into the TN Valley tomorrow ahead of the slowly approaching cold front. Ahead of the front sfc winds will be ~15kts with gusts up to 20-25kts and 25-30kts in the higher elevations. The cold front will move through Thursday night, bringing the rainfall to an end from west to east.
A cold front will bring areas of light snow to eastern Arizona through early evening, with windy and cold conditions behind the front for much of the area. A deepening trough over eastern Arizona this morning is currently bringing areas of light snow to Navajo/Apache counties. This band will be the focus of activity for the remainder of the day, then ending quickly this evening as the trough axis moves into New Mexico.
Skies are mostly sunny across the Keys, with a few more passing cumulus clouds from the Seven Mile Bridge to Key West. However, a persistent, narrow mesoscale convergence zone extends west-northwestward from the Cuban archipelago across the lower Straits of Florida, and over the extreme southeastern Gulf of Mexico, and is providing a focus for development of isolated showers, some producing heavy rain, and with tops occasional exceeding 20,000 feet elevation. Breezy east winds persist thanks to a well-established gradient flow along the southern flank of a sprawling continental high pressure cell covering much of the Eastern Seaboard and adjacent Atlantic waters. Fresh to strong easterly breezes will persist this afternoon across Florida Keys coastal waters, as a sprawling high pressure cell expands over the southeastern United States.
Here a wintry mix of freezing rain, sleet, and snow has already caused travel issues. with minor accumulations of snow/sleet and freezing rain accretion reported. Expect conditions to continue to deteriorate in the ongoing Winter Storm Warning area through this evening as the freezing line continues to work southeast. In southeast MO into southern IL, the loss of cloud ice nucleation may result in periods of freezing drizzle despite the subfreezing temperatures. Have made minor changes to the ongoing snow, sleet and freezing rain forecasts.
Latest visible satellite depicts a low level stratocumulus deck overspreading portions of southeast GA this afternoon as an inverted coastal trough lifts inland. Most shower activity associated with the coastal trough will stay offshore but, as the latest radar returns shows, a few light showers/sprinkles will skirt coastal GA counties through the afternoon then taper off early this evening as the trough lifts northward. Prevailing flow will trend southeasterly overnight as the high pushes further away and a frontal system develops across the northwestern Gulf. Low stratus and some very patchy fog may develop along the I-95 corridor north of Jacksonville tonight in the wake of the lifting inverted trough.
A warming trend begins tomorrow as a large upper-level ridge begins to build onshore across the West Coast.
158 PM MST Wed Feb 2 2022 Large upper trough covers the CONUS, with its axis currently over the Rockies. At the surface, cold high pressure has slid into the Dakotas.
1147 AM CST Wed Feb 2 2022 A forecast update is in place for slightly cooler high temperatures today. This forecast is slightly warmer than the RAP and HRRR models but still holds highs to the single digits across far north central Nebraska. The upper trough axis begins to swing through tonight and will quickly end any lingering light snow from north to south. Still, highs will remain below freezing with WAA remaining somewhat marginal and limited mixing indicated by forecast soundings. Skies remain mostly clear, with subsidence noted on the backside of the large upper trough axis responsible for today's light snow.
Models are showing additional mid level moisture passing atop the high pressure ridge and through our region once again tonight.
1038 AM MST Wed Feb 2 2022 Water vapor imagery shows a vort max pushing through the Dakotas at the moment with a broad upper trough axis extending from MT southward into the Southwest US. As the trough axis pivots eastward, the greatest DCVA and frontogenetic forcing will shift south of the forecast area, clipping the far SW portion of the forecast area.
Currently, long wave trough remains over the Northern Plains region with strong Arctic high pressure across North Dakota. Will also see breezy southerly winds during the day Thursday becoming out of the northwest Thursday night behind an associated cold front.
That being said, the temps in the northeast may be slower to increase to have a bit cooler afternoon highs. The pressure gradient will remain tight enough to support higher winds of 20 to 25 mph with higher gusts mainly in the higher elevations this afternoon and evening.
The sfc freezing line currently extents from far SE OK into west central AR and has slowed its southward progression this afternoon. Further south a transition to sleet and eventually freezing rain is expected with significant and likely damaging ice accumulations expected into portions of far southeast Oklahoma.
1019 AM CST Wed Feb 2 2022 A forecast update is in place for slightly cooler high temperatures today. This forecast is slightly warmer than the RAP and HRRR models but still holds highs to the single digits across far north central Nebraska. The upper trough axis begins to swing through tonight and will quickly end any lingering light snow from north to south. Still, highs will remain below freezing with WAA remaining somewhat marginal and limited mixing indicated by forecast soundings. Skies remain mostly clear, with subsidence noted on the backside of the large upper trough axis responsible for today's light snow.
The higher amounts will be on the southeast side of that gradient.
The winds will stay consistently from the north and relatively gusty, as there is another storm system approaching from the southwest, which will keep us under an enhanced pressure gradient because of the high pressure to the north. We will still be stuck in northerly flow, owing to the slowly approaching high pressure in the northwest. Temperatures will remain cold, with the northwest portion hanging around 10 and into the low teens and then those in the southeast approaching 20.
The first "wave" of precipitation is moving through now and this will occur while low level thermal fields continue to support snow over our northern-northwestern cwfa today with a mix of sleet and freezing rain toward the I-44 corridor and just to the southeast.
Diegan Chattanooga Airport, TN 50 65 40 46 27 / 90 90 90 30 0 Knoxville McGhee Tyson Airport, TN 48 62 37 43 25 / 90 80 100 40 0 Oak Ridge, TN 47 61 35 40 23 / 90 90 100 30 0 Tri Cities Airport, TN 44 60 38 46 22 / 90 90 100 60 10 TN.
254 PM EST Wed Feb 2 2022 High pressure is currently pushing off the eastern seaboard as a cold front starts to push through the midwest.
Broad high pressure over the western Atlantic will continue onshore flow through the period.
High pressure continues to dominate the South Florida weather pattern today. Stout, expansive ridging continues over the western Atlantic waters. The orientation of this feature is such that South Florida is within the southwest periphery of elongated ridging, allowing for the continuation of breezy easterly flow to grace the region, with the higher wind speeds along the east coast (sustained speeds of 10 to 15 mph). Minimum temperatures will remain mild overnight owing to increased moisture/humidity, with minimum temperatures generally in the low/upper 60s along the metros/coasts and mid 50s for the rest of South Florida.
As high pressure builds in overhead tomorrow, sunny skies can be expected with 5-10 knot north/northeasterly winds.
232 PM CST Wed Feb 2 2022 An upper level short wave trough over Arizona is expected to swing eastward across New Mexico tonight and then across the Panhandles on Thursday. The greatest snowfall amounts so far have been in the central Texas Panhandle on northward into the Oklahoma Panhandle on the northern edge of the upper level jet that is found out ahead of the short wave trough.
Moisture continues to advect into the region ahead of an approaching cold front and preceding llj. CDG Chattanooga Airport, TN 55 50 65 40 46 / 80 90 90 90 30 Knoxville McGhee Tyson Airport, TN 57 48 62 37 43 / 60 90 90 100 40 Oak Ridge, TN 55 47 61 35 40 / 80 90 90 100 30 Tri Cities Airport, TN 54 44 60 38 46 / 40 90 90 100 60 TN.
There is still a text-book Denver cyclone over the greater Denver area. The water vapor satellite pictures indicate that the upper trough axis is stretched from northwestern Colorado down into eastern Arizona. The upper trough axis is slow in moving eastward overnight. Some of the high resolution models show areas of fog developing over the plains of Weld County and the Denver Metro area towards morning. There is general agreement among ensemble guidance for mostly ridging in the upper levels with a brief period or two with a weak trough passage.
Warmer temperatures then build in heading into the new week. High pressure stretched from southern Saskatchewan into the Northern Plains and was building eastward. A fairly tight pressure gradient between this high and low pressure in the Ohio Valley was leading to some breezy winds across the region this afternoon under partly to mostly sunny skies. As the core of this high spreads eastward overnight, clear skies and light winds will allow for good radiational cooling conditions. With the core of the high still to our west tonight, light winds will lead to wind chills of 30 to 45 below zero, coldest along the International Border into the Minnesota Arrowhead.
The TN Valley is in between a ridge off the Atlantic coast and an elongated trough out west. The anchored LLJ will finally slide eastward tonight, allowing for gusts to slack after sunset, however the tight gradient in place will keep winds elevated, especially in the higher terrain. A 50-60kt LLJ will slide into the TN Valley tomorrow ahead of the slowly approaching cold front. Ahead of the front sfc winds will be ~15kts with gusts up to 20-25kts and 25-30kts in the higher elevations. The cold front will move through Thursday night, bringing the rainfall to an end from west to east.
The cold front is now moving into our far northwestern sections at this time. Temperatures range from the upper 30s in our far northwest corner to the lower 50s south. Your overnight lows by morning will range from the lower to mid 30s far northwest to near 50 far south central areas and the southern plateau. The southeastward extent/timing of the surface freezing line is still a bit iffy. Meanwhile, the cold front will continue to slowly work southward through the taf period. At CKV, look for some freezing rain to begin between 15Z and 18Z, with the frozen precip becoming prevalent aft 18Z.
A western conus trough axis is currently draped from the Northern Plains down through the Desert Southwest through Baja.
The high will build into the area tonight and move through during the day on Thursday. All this is makes the low temperatures a bit of a challenge for tonight. Along with the upper waves, there are a couple of cold fronts that will lower temperatures for a short time, but temperatures are expected to be warmer than normal much of the time.
Dry and colder air will invade the area tonight resulting in below freezing temperatures across nearly all of southeast Arizona Thursday morning.
Can't completely rule out a light flurry or two along the higher elevations of the upslope but better chances for a snow shower exist behind the low on northwest flow. The moisture profile in the trough is similar late Thursday night and could be squeezed out in the weak caa between the low and the arctic high.
At the surface, a low pressure system is located over southern New Mexico and an Arctic high pressure system was moving across the northern United States. It is this Arctic high pressure that is responsible for the bitterly cold temperatures being observed. Aloft, a deep trough of low pressure extended from the northern Great Plains to the Desert Southwest. This event was quite interesting as it does seem the liquid equivalent verified in some locations, but the snow ratios were the problem and thus caused the storm total snowfall to not materialize to the higher levels advertised.
There is an upper trough centered over the Hudson Bay while an upper ridge is off in the eastern Pacific.
A cold front will bring areas of light snow to eastern Arizona through early evening, with windy and cold conditions behind the front for much of the area. Showers are diminishing from northwest to southeast as drier boundary later air pushes south, that coupled with an exiting trough axis, will bring showers to an end this evening over southern Apache County. Continued marginally unstable air, northerly flow and a follow-up s/wv on Thursday, will keep a a threat for flurries over the higher elevations of the White Mtns, but any organized or accumulating snow bands will end this evening.
Lee troughing will develop this evening, bringing strong and gusty winds from Livingston to Big Timber to Judith Gap overnight. Likewise, strongest winds in the foothills will subside through the early morning hours Thursday, as the leeside trough slackens a bit. Leeside troughing redevelops Thursday evening bringing another period of strong gap flow winds overnight, with gusts exceeding 60 mph expected from Livingston to Big Timber and Nye.
Looks like the highest push would succeed most or all of the falling snow, and the more west northwest surface wind direction could keep impacts lower along the spine of the Valley.
/Issued 232 PM CST Wed Feb 2 2022/ An upper level short wave trough over Arizona is expected to swing eastward across New Mexico tonight and then across the Panhandles on Thursday. The greatest snowfall amounts so far have been in the central Texas Panhandle on northward into the Oklahoma Panhandle on the northern edge of the upper level jet that is found out ahead of the short wave trough.
441 PM MST Wed Feb 2 2022 Large upper trough covers the CONUS, with its axis currently over the Rockies. At the surface, cold high pressure has slid into the Dakotas.
323 PM CST Wed Feb 2 2022 1047 mb arctic high pressure centered over Saskatchewan this afternoon will build into the upper Midwest and ridge south through ern Neb and KS tonight. The cooler lows across ncntl Neb are close to the 25th percentile of the NBM. The arctic high pressure will continue building south and east into the srn Plains and Midwest Thursday and Thursday night.
Light precipitation across the region with a weak warm front approaching.
424 PM MST Wed Feb 2 2022 The mid-level trough axis extended from northwest Colorado across southeast Utah early this afternoon according model analyses. Showers diminish later tonight as the trough finally shifts east of the Continental Divide, but scattered showers are expected to continue in the higher terrain southeast of Pagosa Springs through morning. A weak disturbance moving down the backside of the exiting trough may result in some isolated showers over that area during the afternoon, but otherwise, mostly sunny skies and unseasonably cold temperatures are expected across the region.
Freezing rain is now occurring along and north of I-20 corridor while sleet is mixing in with rain for areas further south. Meanwhile, the steady north winds are pushing sub-freezing air at the surface. As this colder air continues to move south, precipitation will change over from rain to snow, sleet and freezing rain this evening, then eventually all snow for the Concho Valley northward overnight. A mix of snow, sleet and freezing rain will persist for areas southward through at least tomorrow morning. Skies will continue to be overcast even after the precipitation ends, and highs will struggle to get out of the low 20s for most locations.
542 PM CST Wed Feb 2 2022 1047 mb arctic high pressure centered over Saskatchewan this afternoon will build into the upper Midwest and ridge south through ern Neb and KS tonight. The cooler lows across ncntl Neb are close to the 25th percentile of the NBM. The arctic high pressure will continue building south and east into the srn Plains and Midwest Thursday and Thursday night.
The upper ridge pattern offshore continues with an upper trough cycling down the backside tonight into Thursday morning. Although there is a slight increase in low level moisture, mostly on the west side in Oregon, with the northerly flow above the ridge tops moisture remains limited. The bulk of the light precipitation will be ahead of the trough this evening into tonight. However, with the ridge building back in and shifting eastward behind this short wave, offshore flow returns across the west side, allowing clearing over much of the area except for the Upqua Basin and the northern coast.
The highest amounts are expected near or just to the east-southeast of I-44.
715 PM EST Wed Feb 2 2022 Breezy east/southeast wind are starting to subside this evening as high pressure holds across northern Florida.
301 PM MST Wed Feb 2 2022 The mid-level trough axis extended from northwest Colorado across southeast Utah early this afternoon according model analyses. Showers diminish later tonight as the trough finally shifts east of the Continental Divide, but scattered showers are expected to continue in the higher terrain southeast of Pagosa Springs through morning. A weak disturbance moving down the backside of the exiting trough may result in some isolated showers over that area during the afternoon, but otherwise, mostly sunny skies and unseasonably cold temperatures are expected across the region.
419 PM EST Wed Feb 2 2022 Today has been warmer and more humid in the Florida Keys thanks to a persistent fresh to strong easterly breezes rooted in highly modified continental air with a long over-subtropical-water trajectory. The surface weather map this afternoon features an arctic anticyclone and a modified continental anticyclone flanking a major winter storm system currently dumping heavy snow across the Hoosier State and surrounding areas. The Florida Keys lie along the southwestern periphery of the sprawling continental anticyclone which extends from the Canadian Maritimes southwestward to the northwestern Caribbean Sea. The governing high pressure cell will slowly weaken and shift eastward, leading to diminishing breezes starting Thursday night.
627 PM CST Wed Feb 2 2022 Extreme cold conditions this evening and overnight expected with a 1042mb arctic high pressure building into the region. Looks like the highest push would succeed most or all of the falling snow, and the more west northwest surface wind direction could keep impacts lower along the spine of the Valley. Another night of SKC and extreme cold conditions with light winds as arctic high pressure slides across the region. Behind the high south winds will develop with Thursday afternoon winds at 10 to 15kts.
Strongest winds are located along the west side of the Sacramento Valley, as well as the wind-prone mountain/foothill canyons, gaps, and ridgetops. The dry airmass combined with reduced boundary layer-mixing will promote cooler overnight temperatures in the Sacramento Valley and northern San Joaquin Valley.
900 PM EST Wed Feb 2 2022 Broad high pressure across the western Atlantic will maintain a light SE wind flow overnight, around 5 mph interior and around 10 mph beachside. More of the same as the high pressure in the western Atlantic continues to control conditions in Florida. Broad high pressure over the western Atlantic will maintain a SE flow, with a pressure gradient supporting 15 knots, occasionally up to 20 knots offshore.
As a result of this, snow amounts in these areas may be a bit lower than previously forecast, but as stated in past discussions the greater impacts for our SE counties (especially along and S of US-24) would come tonight into Thursday evening with the second wave of low pressure.
A fairly restrictive and variable taf cycle ahead for all sites as moisture continues to increase across the region ahead of an approaching cold front. CDG Chattanooga Airport, TN 64 41 46 26 46 / 100 100 30 0 0 Knoxville McGhee Tyson Airport, TN 64 38 43 24 43 / 80 100 50 0 0 Oak Ridge, TN 60 37 41 23 43 / 90 100 40 0 0 Tri Cities Airport, TN 61 42 49 21 40 / 90 100 70 0 0 NC.
There is some light precipitation falling from the lower clouds, but reported amounts have been light. The Charlotte Ridge RAWS recorded 0.
Light precipitation across the region with a weak warm front approaching. A cold front crosses on Friday with more widespread precipitation. High pressure builds over the weekend for a return of drier and slightly warmer conditions across the area.
Warmer temperatures then build in heading into the new week. High pressure stretched from southern Saskatchewan into the Northern Plains and was building eastward. A fairly tight pressure gradient between this high and low pressure in the Ohio Valley was leading to some breezy winds across the region this afternoon under partly to mostly sunny skies. As the core of this high spreads eastward overnight, clear skies and light winds will allow for good radiational cooling conditions. With the core of the high still to our west tonight, light winds will lead to wind chills of 30 to 45 below zero, coldest along the International Border into the Minnesota Arrowhead. Quiet and cold for Thursday as the high moves through region before a weak clipper passes through for Thursday night into Friday.
At the surface, a low pressure system is located over southern New Mexico and an Arctic high pressure system was moving across the northern United States. It is this Arctic high pressure that is responsible for the bitterly cold temperatures being observed. Aloft, a deep trough of low pressure extended from the northern Great Plains to the Desert Southwest. This event was quite interesting as it does seem the liquid equivalent verified in some locations, but the snow ratios were the problem and thus caused the storm total snowfall to not materialize to the higher levels advertised. Fri-Wed: Long range guidance suggests that the High Plains will be situated on (or near) an inflection point in the synoptic pattern. between a west CONUS ridge and an east CONUS trough.
/Today through Friday/ Southwest flow aloft ahead of an approaching upper-level trough across the Four Corners region continues to advect Pacific moisture across the ArkLaTex this morning. Temperatures north of the boundary remain slightly above freezing allowing for widespread rain above the colder airmass. Going forward, temperatures forecast to fall below freezing across McCurtain county over the next couple of hours generating an initial freezing rain threat. Throughout the remainder of the overnight hours into mid morning, conditions to deteriorate across much of east and northeast Texas into southern Arkansas as temperatures fall below freezing across these areas. Current thinking is that winter weather threat will start as freezing rain and gradually progress into a sleet/snow threat by mid to late afternoon with portions of southeast Oklahoma eventually transitioning into a snow threat.