Aikyam-Lab/Synoptic-Bench huggingface dataset:
Given this, the expanding area of fog seen on satellite, low visibility seen via webcam in Panhandle, the slowing of traffic along Highway 60 between Amarillo and Pampa and along Interstate 40 between Amarillo and McLean, and the likelihood that light winds will continue for several hours, have issued a Freezing Fog Advisory for the south central Texas Panhandle through noon this morning. As this occurs, longwave trough currently over the eastern CONUS will advance eastward, with large scale surface ridging setting up in the wake of this feature.
(Today through Sunday) Warmer temperatures are expected today with temperatures expected to get above freezing areawide. Most of the area should be above freezing through the night, but some areas in the west may be near or slightly below freezing, so some freezing fog will be possible.
447 AM MST Sat Feb 20 2021 The short term forecast focus is on the low pressure system that moves quickly across the region overnight tonight, bringing the possibility of light snow with areas of light freezing drizzle and fog. An upper trough moves through the Intermountain region today, east of the Rockies tonight, and across the plains states on Sunday. Some locations may see a light glaze of ice with the fog and freezing drizzle, but confidence in any widespread ice accumulations or impacts is low. Temperatures that have been warming each of the past few days will be shunted briefly on Sunday in the wake of the cold front.
Expect VFR conditions to prevail across the Rio Grande Valley today through tonight as a 500mb ridge across eastern Mexico continues to provide subsidence across northeast Mexico and deep south Texas. Temperatures will be at least 10 degrees warmer today compared to yesterday but remain below normal. Warm air advection will increase across deep south Texas tonight as a 500mb trough developing across the western United States moves into the southwest United States. Temperatures will be at least 20 degrees warmer compared to this morning and will be slightly below normal to near normal across the Rio Grande Valley. The upper level trough is expected to move into southern New Mexico and west Texas Sunday. Breezy conditions will develop across the lower Texas coast Sunday even as a Pacific cold front moves into northwest Texas Sun afternoon.
819 AM EST Sat Feb 20 2021 High pressure centered in the lower Mississippi valley this morning eases eastward today with a dry cool northerly flow prevailing across the area. High pressure moves by to the north during the next couple of days with veering winds.
available moisture in the low levels should be sufficient for the formation of fog this evening and overnight. likely beginning as freezing drizzle near and southeast of the Tri-cities before transitioning to all snow by Sunday morning. With a good signature for freezing drizzle in both soundings and in precip fields from the NAM.
Light lake effect snow showers and flurries will come to an end by early this afternoon as much warmer and drier air spreads over the Upper Great Lakes region from the west. Some warmer air aloft will not be able to mix down causing afternoon highs to remain much below normal from 20 to 25. Otherwise VFR this period as skies clear in association with weakening low level thermal trough across lake MI and general backing flow to swrly. However this will also usher is better low level moisture late period manifested as MVFR cigs as warm advection begins to ramp inadv of developing cntrl plains low pressure.
High pressure is currently parked over Middle Tennessee and with clear skies, calm winds, and snow on the ground, temperatures have been able to drop efficiently down into the teens area wide with even a couple single digit readings. Surface obs and the nighttime microphysics shows some patchy freezing fog scattered through the CWA. Tonight won't be as cold with high pressure sliding off to the east and a light southerly component developing in the low levels. Sunday will still have plenty of sunshine and temperatures in the low to mid 50s. South winds will increase on Sunday ahead of a low pressure system that will be lifting out of the central plains toward the Great Lakes Sunday night.
A storm system will push a cold front through the area today.
This has resulted in the development of some freezing fog and also helped slow the temperature plummet that was expected. After the fog and freezing temperatures this morning, we are looking for a pretty nice day compared to the past several with temperatures warming from near 50 to the mid 50s.
428 AM MST Sat Feb 20 2021 Winds will continue to increase across southern CO ahead of the next upper-level trough forecasted to pass over us this evening. As the upper low approaches the area, southwest flow will begin to increase over the mountains and adjacent valleys and plains, reaching gusts of 25-30 mph. The exact amounts have varied between model runs, but given the amount of lift from upslope winds, frontogenetic forcing and the passing of the upper low, it is possible these snow showers could have more convective characteristics, meaning snow amounts and rate could vary locally.
and Sunday Mostly clear skies and cold temperatures are expected this morning as high pressure tracks across the western Great Lakes region. Temperatures today should rebound into the lower to middle 20s with abundant sunshine. Lows tonight are expected to fall into the single digits above zero as clouds increase from west to east ahead of an approaching low pressure system. A low pressure system developing across the central Plains region late tonight, will race northeast towards eastern Iowa by late Sunday afternoon. The highest totals are expected across central Wisconsin where snow will be falling for the longest period and lowest across far north-central Wisconsin given more dry air and the shorter time the light snow is expected.
416 AM CST Sat Feb 20 2021 High pressure is over the forecast area as we start off cold this morning. Most places today should rise above freezing today and this combined with full sun once again should help melt snow and ice today. Look for more refreezing of residual liquid again tonight.
/Issued 236 AM EST Sat Feb 20 2021/ High pressure will continue to build in from the west today and then move overhead tonight. The high center will continue to push east across the Middle Atlantic on Sunday. Winds do switch around to the east late tonight/early Sunday and low level moisture will begin to increase ahead of an approaching cold front.
812 AM EST Sat Feb 20 2021 High pressure will build into the Tennessee Valley today then over the central Appalachains by Sunday providing dry but cold weather through the weekend.
High pressure will yield a totally dry day on Sunday.
559 AM CST Sat Feb 20 2021 Warmer weather will be on tap this weekend. Given the insulating blanket of clouds, current temps are considerably warmer than they have been in recent nights in the teens and lower 20s.
Tonight, WAA increases as a ridge builds overhead tonight. Upper air pattern will consist of a 500 mb trough in the northern and central plains 12z Sun that will move into the upper Great Lakes 00z Mon and out of the area on Mon. In the extended, the GFS and ECMWF show a 500 mb trough over the northern Rockies and another over the eastern U. The trough over the northern Rockies remains 12z Wed and then this moves into the upper Great Lakes by 12z Thu and into the lower Great Lakes by 12z Fri. On 12z Sat, there is a deep trough over the Rockies and a ridge over the eastern U. VFR conditions are expected at all TAF sites through this forecast period as ridging moves overhead.
420 AM CST Sat Feb 20 2021 Current surface analysis places high over the Mississippi River Valley with trough to the lee of the northern Rockies. Upper level analysis places trough sliding over the west coast and modest ridging over the southern Rockies into the northern plains. Broad ridge sets up over the region to start the week, resulting in very mild temperatures.
343 AM CST Sat Feb 20 2021 We will sit under weak upper level ridging today as two upper waves begin to move east towards the CWA. Ahead of the waves south-southwesterly surface flow and plenty of sunshine will result in another warmer day for the region. By early tomorrow morning the associated Pacific cold front will begin to impact our area. More on that in Sunday morning will see an UL positively tilted trough positioned from AZ to NE thence curving northward toward a low pressure system over the Arctic.
419 AM MST Sat Feb 20 2021 The short term forecast focus is on the low pressure system that moves quickly across the region overnight tonight, bringing the possibility of light snow with areas of light freezing drizzle and fog. An upper trough moves through the Intermountain region today, east of the Rockies tonight, and across the plains states on Sunday. Some locations may see a light glaze of ice with the fog and freezing drizzle, but confidence in any widespread ice accumulations or impacts is low. Temperatures that have been warming each of the past few days will be shunted briefly on Sunday in the wake of the cold front.
/issued 416 AM CST Sat Feb 20 2021/ High pressure is over the forecast area as we start off cold this morning. Most places today should rise above freezing today and this combined with full sun once again should help melt snow and ice today. Look for more refreezing of residual liquid again tonight.
921 AM EST Sat Feb 20 2021 High pressure will build east into the Ohio Valley today. The high will then move east of the region tonight.
HRRR indicate sfc temps considerably warmer than NCEP model guidance. 06z HRRR indicates highs above freezing over the western edge of the RRV from Walhalla to west of Grand Forks with pocket of near 40 psbl. To account for a bit warmer temps in the western RRV did go a tad higher than blended model guidance in that area, while kept rest of the area near blend. Tonight will see weak 700 mb trough move east from northern Wyoming into northern SD and a band of moisture on the northeast side of the trough spreading from NE SD into central MN, clipping SE ND.
The cold front has pushed through the state this morning, with the trailing stratocu cloud deck lingering across the southern half of the area. These clouds will be gradually clearing through the morning, with mostly clear skies then through the afternoon as high pressure continues to build into the area and bring cooler and drier air down the state on northerly winds. High pressure center shifts east tonight and Sunday, turning winds to the NE tonight and E for Sunday, allowing for some moderating of temps and moisture. Lows tonight in the lower 40s north to lower 50s south.
Current surface analysis places high over the Mississippi River Valley with trough to the lee of the northern Rockies. Upper level analysis places trough sliding over the west coast and modest ridging over the southern Rockies into the northern plains. Broad ridge sets up over the region to start the week, resulting in very mild temperatures.
An upper level trough moving across the Great Basin has caused surface pressure falls in the Plains resulting in southerly lower level flow returning to South Central Texas allowing warm advection to get underway. The warming and moistening trend will result in much warmer low temperatures as low clouds return tonight with no areas of freezing temperatures expected. However, spots with snow cover remaining and a later arrival of low clouds may approach freezing. The upper level trough moves across the Plains Sunday dragging a cold front across our area Sunday night.
We will be under ridging aloft during the day Sunday along with return flow out of the south. Even with remaining snowpack, our temperatures will be warmer than they have been since Feb.
Upper ridging will build into the Tennessee valley and southern Appalachians through Sunday producing mostly clear sky. Some increase in high level cloudiness expected Sunday as upper ridge axis moves into the area. Some light snow possible in the higher terrain of East Tennessee and southwest Virginia. Gusty winds expected in the higher terrain of the East Tennessee mountains, and adjacent foothills.
An upper trough is beginning to dig southeastward across the western part of the country. The upper trough to the west will move over the central part of the country on Sunday with the base of the upper trough moving over West Texas and Southeast New Mexico. High winds from the base of the trough are expected to impact the Guadalupe Mountains so a High Wind Warning is in effect there beginning tonight and continuing into the early morning hours on Sunday. The upper trough will result in a cold front moving into the area during the day on Sunday.
228 PM CST Sat Feb 20 2021 Temperatures finally above freezing over a wide area today with abundant sunshine. Looks like temperatures will be above freezing for the most part, but can't rule out brief freezing drizzle in some of the Ozarks hills in the morning with precip onset.
Patchy drizzle is possible overnight with scattered light showers likely developing Sunday as the next cold front passes.
246 PM CST Sat Feb 20 2021 A weak cold front will move through Sunday night with a few light showers followed by only a brief modest cool down. This is allowing a light east to southeast flow to develop in the low levels across the forecast area. Next cold front, with air mass from more of a Pacific origin, will move across the forecast area on Sunday night.
High pressure centered north of the area will provide for clear skies and dry conditions for the next 24 hours. Some patchy frost is possible tonight in the cooler, more sheltered locations.
Tonight, WAA increases as a ridge builds overhead tonight. Upper air pattern will consist of a 500 mb trough in the northern and central plains 12z Sun that will move into the upper Great Lakes 00z Mon and out of the area on Mon. In the extended, the GFS and ECMWF show a 500 mb trough over the northern Rockies and another over the eastern U. The trough over the northern Rockies remains 12z Wed and then this moves into the upper Great Lakes by 12z Thu and into the lower Great Lakes by 12z Fri. On 12z Sat, there is a deep trough over the Rockies and a ridge over the eastern U. VFR conditions expected to prevail at all terminals as ridging builds aloft today.
Sunny weather will continue this afternoon with temperatures warming into the lower 30s to mid 40s. /issued 416 AM CST Sat Feb 20 2021/ High pressure is over the forecast area as we start off cold this morning. Most places today should rise above freezing today and this combined with full sun once again should help melt snow and ice today. Look for more refreezing of residual liquid again tonight.
1110 AM CST Sat Feb 20 2021 Warmer weather will be on tap this weekend. Temperatures continue to generally run a little warmer than expected this morning and have adjusted hourly trends to adjust for latest observations. That said, afternoon highs still on track under a mix of sun and clouds and continued snow pack that will help keep temps at or just below freezing this afternoon. Given the insulating blanket of clouds, current temps are considerably warmer than they have been in recent nights in the teens and lower 20s.
245 PM EST Sat Feb 20 2021 Snow, mixed with rain, is expected Sunday night as temperatures warm into the low to mid 30s. This WAA regime will finally allow the arctic cold to begin its retreat with temps tonight falling or steady in the teens, warming into the low-mid 30s tomorrow. Sunday night's weather maker, now entering the Rockies, will eject east as an amplified positively titled upper trough.
1224 PM EST Sat Feb 20 2021 High pressure will build east into the Ohio Valley today. The high will then move east of the region tonight.
/Updated at 1045 AM CST Sat Feb 20 2021/ Short term forecast is on track as high pressure is set to prevail through tomorrow.
1022 AM EST Sat Feb 20 2021 Much cooler and drier airmass has settled across the region behind yesterday's cold front with most mainland locations seeing low temperatures ranging from the mid 40s to lower 50s this morning. High temperatures will reach the low-mid 60s north of Orlando, and upper 60s to near 70 degrees to the south.
Surface ridging and developing upper ridge will produce a quiet weather pattern. Due to surface ridging, winds will be light and generally less than 5kts.
330 PM EST Sat Feb 20 2021 Cold high pressure will build overhead tonight and Sunday morning, then shift offshore Sunday night.
1144 AM CST Sat Feb 20 2021 High pressure continues over the area this morning. As a warm front approaches tonight, moisture will increase and lead to patchy fog and increasing low clouds. The low clouds are progged to gradually expand to the N and E this mrng, mainly affecting locations along and E of the I-30/Hwy 67/167 corridor. Similar to Fri, the coldest highs today wl again where the highest snow cover exists, with highs topping out in the 30s. Models rmn consistent showing a positively tilted upr trof swinging thru the region late in the weekend.
Temperatures just a smidge "warmer" on Sunday, with highs mostly in the lower 30s.
Today, despite high albedo of snow cover, advection has aided temperatures rising above freezing for the entire area, accelerating melting of snow compared to yesterday. Though sub-freezing temperatures could result in freezing fog for some locations, scenarios with the most significant deposition and riming occur with temperatures less than -10C (14F). The depth of low- level saturation in the forecast soundings may support some light drizzle primarily east of the freezing line, across south-central and southeast Oklahoma. One final note: For areas that do fall below freezing tonight, snow meltwater may refreeze causing areas of black ice and resultant slick spots on roads, sidewalks, etc.
/issued 819 AM EST Sat Feb 20 2021/ High pressure centered in the lower Mississippi valley this morning eases eastward today with a dry cool northerly flow prevailing across the area. High pressure moves by to the north during the next couple of days with veering winds.
Otherwise, increasing flow off the deck tonight ahead of an upper level short wave trough over the Colorado Rockies will result in a period of LLWS followed by the passage of a cold front after sunrise Sunday. /issued 343 AM CST Sat Feb 20 2021/ We will sit under weak upper level ridging today as two upper waves begin to move east towards the CWA. Ahead of the waves south-southwesterly surface flow and plenty of sunshine will result in another warmer day for the region. By early tomorrow morning the associated Pacific cold front will begin to impact our area. More on that in Sunday morning will see an UL positively tilted trough positioned from AZ to NE thence curving northward toward a low pressure system over the Arctic.
151 PM CST Sat Feb 20 2021 An upper level short wave trough will move from the Wyoming/Colorado Rockies early evening to the central Plains by noon Sunday. Energy and moisture associated with the trough will be too far north to merit any precip chances for the forecast area, but the trough will bring a cold front through the area Sunday morning. Pressure falls ahead of the trough and the front tonight should help keep south winds, and thus temperatures, up some tonight while modest post- frontal cold advection will be worth around ten degrees cooling from today's highs.
Under strong high pressure ridging, the winds will generally be light and variable. Where radiative heat loss has been strongest, patchy fog and in some cases freezing fog has formed, primarily over areas where ice/snow is still on the ground. Clear skies and calm winds early tonight will allow temperatures to fall quickly during the evening, but as the high pressure ridge eventually drifts east of the area, increasing southerly surface winds may actually raise temperatures after midnight. It will still be cold as minimums once again fall below freezing.
943 AM CST Sat Feb 20 2021 Warmer weather will be on tap this weekend. Temperatures continue to generally run a little warmer than expected this morning and have adjusted hourly trends to adjust for latest observations. That said, afternoon highs still on track under a mix of sun and clouds and continued snow pack that will help keep temps at or just below freezing this afternoon. Given the insulating blanket of clouds, current temps are considerably warmer than they have been in recent nights in the teens and lower 20s.
329 PM EST Sat Feb 20 2021 High pressure will build into the area through the weekend.
As of mid afternoon, the warmest air since mid to late January (sounds weird actually saying that) has made it into the Devils Lake region, where temperatures have crossed into the low 30s. By Sunday afternoon, southwest winds will pick up a little more, which should allow temperatures across the entire area to get into the low to mid 30s. There's a possibility for a system associated with a longwave trough to impact us this weekend, but given that it is so far ahead in time, confidence is low on the system even holding together to produce snowfall in the northern plains.
245 PM CST Sat Feb 20 2021 Main forecast challenge/concern is freezing drizzle and icing potential overnight into Sunday morning. Isentropic lift and better low level warm/moist advection tonight ahead of the approaching upper trof is expected to promote some very light precip, mainly drizzle and freezing drizzle. Confidence remains highest for locations to stay below freezing long enough for a Winter Weather Advisory along/north of highway 50, though a period of icing is possible as far south as highway 54 where existing snow cover may allow for temperatures to drop and stay just below freezing as the drizzle starts, before enough warming in the southerly flow develops toward dawn. A brief period of light snow is possible Sunday morning across central Kansas behind the surface cold front if there is enough moistening/lift within the cold advection under the upper trof.
Morning sounding is very dry so precipitation isn't likely this afternoon until trof pushes across tonight. Warm front has moved through the area with temperatures in the 30s. Further south and east, a band of snowfall is likely to develop from parts of western and central NE into south central and eastern SD this evening and overnight near the eastward moving front/trough. Also added a slight chance for freezing rain late this evening/overnight over parts of far south central SD before the front arrives.
NAM remains the strongest with a closed low across Iowa and unrealistically high QPF across southern Minnesota.
However, a few spots with deeper residual snow will remain below freezing for the next hour or two. This leads to some concern for potential freezing fog by morning, but forecast HRRR soundings really don't support the dense fog that would be required for impacts and will continue to not mention anything in the forecast for now.
The influence of this high pressure will keep conditions dry amd precipitation-free through the remainder of the day today and into tomorrow. The high pressure center will slide just north of the forecast area overnight and continue to move eastward towards the Mid-Atlantic on Sunday. Surface winds will shift to the E to SE on the back side of the high as it continues to move away from the forecast area, allowing for gradual low level moisture return over the forecast area. Temperatures will be below average through the short term period, more so today than tomorrow, as they will moderate closer to climatological normals underneath the ridge tomorrow.