Aikyam-Lab/Synoptic-Bench huggingface dataset:
546 PM CST Wed Feb 23 2022 Back to the trough of the temperature wave we go as high struggle to reach just over 20 degrees. Areas north of US-50 are expected to see mainly snow with places south of US-50 potentially seeing a little bit of freezing drizzle and/or sleet mixed in. Model vertical profiles show a slightly favorable environment toward mixing freezing drizzle and/or sleet in with snow as the warm nose aloft approaches 0C and the vertical column resides between -1C and -12C, just warmer than the dendritic growth zone. If the 0C line shifts further north, more freezing rain and sleet will be mixed in the precipitation.
Temperatures have steadily dropped area-wide behind a departing surface cold front, with locations around the Brazos Valley already reporting readings near or below freezing this afternoon. Lows this evening will approach or drop below freezing across most locations to the north and northwest of the Houston metro area, with locations in and around the Brazos Valley expected to dip into the upper 20s. Given the expected temperature trend, this will lead to periods of freezing rain and drizzle across our northwestern zones through tomorrow morning. 05"), travel on elevated roadways and bridges may still become hazardous. Temperatures will once again approach freezing tomorrow evening and likely drop below freezing across the northern third of the area. With scattered showers expected to continue during this time, additional periods of light freezing rain/drizzle may be possible.
A cold front has stalled near the I-20 corridor. Weak 5h ridging will continue over the southeast into Thursday within a wide expanse of southwest flow atop the shallow Arctic air across the south central states into the lower OH valley.
The strong low pressure center is located over southwest Utah this afternoon and will slowly shift eastward this evening to near the four corners around midnight.
Still seeing areas of light freezing drizzle or flurries at this time, and the lake Oologah snow machine appears to have slowed down for the moment at least. The thermal profiles eventually become more supportive of freezing rain up to roughly the I-44 corridor, with highest chance of accumulating ice through 12z remaining confined to areas near the Red River and in the Arkansas River valley in western AR. (Tonight through Wednesday) As main upper trough axis approaches late tonight into Thursday morning. Areas of sleet and freezing rain will begin to increase again. Still the potential for Arkansas river valley to warm above freezing by early afternoon.
132 AM EST Thu Feb 24 2022 Colder and drier air will filter into the region tonight behind the cold front.
Cold temperatures will continue through Thursday, then high pressure aloft to the west of the state will bring a warming trend with periods of Santa Ana winds through the weekend. An upper-level trough of low pressure continues to exit the region this evening leaving a cold and drier air mass in its wake.
248 AM CST Thu Feb 24 2022 The center of an upper level low was currently located near the 4- corners early this Thursday morning. Nonetheless, we have gone on the lower side of guidance spread for temperatures this afternoon.
236 AM CST Thu Feb 24 2022 Scanning the far northwest, we are still looking at near to slightly below freezing temperatures for the Stewart, Montgomery and Houston county area. A warm front will be lifting northward by afternoon and this will likely give our southern counties a bit of a break.
/issued 907 PM CST Wed Feb 23 2022/ A mix of rain, freezing rain, and sleet continues across the Mid South. Some places along I-40 have seen some light freezing rain. Areas north and west of I-40 are seeing more sleet and freezing rain. We have already seen thunder snow, thunder sleet, and thunder freezing rain across eastern Arkansas. We have seen reports up to half an inch of sleet in 30 minutes, which has accumulated on the bridges. This would reduce the amount of sleet drastically, but result in freezing rain accumulations approaching a half an inch by tomorrow morning across the winter storm warning area.
The biggest reason is snowfall amounts this high are highly dependent on snow ratios being much greater than climatology (13:1).
As the day progresses the warm southwesterly conveyor belt aloft will continue to advect moisture into the area as upper level high pressure remains settled over the Gulf Coast.
The low continues to move to the east and is located over southeast Utah this evening and will move towards the four corners region later tonight. The strong low pressure center is located over southwest Utah this afternoon and will slowly shift eastward this evening to near the four corners around midnight.
1027 PM MST Wed Feb 23 2022 Upper level analysis and water vapor imagery depict two primary upper lows: one over the Hudson Bay and another centered over Nevada. A trough axis extends from the Hudson Bay low southwestward into the east-central MT southwestward into the southwest US. At the surface, high pressure is centered over northeastern SD and will remain fairly stationary before the southwestern low ejects eastward. As the southwestern low ejects eastward and the upper trough axis pivots through the forecast area, expect some light snow later this evening across the far southern portion of the forecast area.
Snow chances return tonight as a mid to upper level trough approaches from the west this afternoon and evening. This area of low pressure will track northwest along an associated baroclinic zone draped across the Ohio Valley. As the low advances into southern Ohio this evening, the leading edge of the isentropic ascent will likely reach up into the I-94 corridor by 0z tonight with light snow overspreading the entire area by 06z. Ratios will also increase towards 15/18:1 as 850mb temps drop on the backside of the low allowing for deeper saturation in the DGZ.
958 PM MST Wed Feb 23 2022 Early afternoon GOES-W WV imagery showed a upper level trough centered over the Great Basin. The upper trough to the southwest will weaken as it tracks east through the Central/Southern Rockies tonight and Thursday morning. This system will increase the low level upslope to produce periods of light snow tonight, with snow tapering off from west to east Thursday morning.
1122 PM CST Wed Feb 23 2022 Back to the trough of the temperature wave we go as high struggle to reach just over 20 degrees. Areas north of US-50 are expected to see mainly snow with places south of US-50 potentially seeing a little bit of freezing drizzle and/or sleet mixed in. Model vertical profiles show a slightly favorable environment toward mixing freezing drizzle and/or sleet in with snow as the warm nose aloft approaches 0C and the vertical column resides between -1C and -12C, just warmer than the dendritic growth zone. If the 0C line shifts further north, more freezing rain and sleet will be mixed in the precipitation.
1106 PM CST Wed Feb 23 2022 A weak wave ahead of a developing trough in the Rockies will bring a small chance for snow to areas near the Missouri River this evening and early night time hours. Otherwise cold high pressure will be in place but with the main trough lifting onto the Plains overnight clouds will increase so radiational cooling will not be maximized. Instability does not look to play a major role with this system, but favorable temperatures aloft for snow as well as lighter winds in the lower 5000 feet or so of the atmosphere should help maximize snow ratios, which will likely be close to 20:1.
243 AM CST Thu Feb 24 2022 Northeast low level flow continue to bring a patchy, but remarkably persistent stratus deck over the CWA and the lower Great Lakes early this morning.
Overall the result will likely be temperatures about 4-7 degrees warmer on average the next overnight period, with winds continuing to lighten up as the sfc pgf weakens.
By the weekend, a high pressure ridge will build over the southwest causing temperatures to warm back to near normal levels. This area expected to continue to weaken/dissipate over the next 2 hours as cold upper trough exits east across Arizona. Unseasonably cold temperatures will continue through the end of the week as models indicate a broad trough of low pressure remaining carved out across the region.
This temperature gradient is thanks to the cold front stalled across the region, roughly from around Meridian to Brookhaven. Behind this, cooler air with light northerly winds is prevailing. The southerly winds will take over again, pushing the now warm front back up and through the forecast area tomorrow. A deep upper trough then finally starts to eject out of the SW and across the region, pushing the front back to the south by late afternoon/evening. The only concern for a more active afternoon is that persistent southerly flow holding the front/cooler air to the north. though parameters are less impressive and temps even cooler.
The approaching trough will move into the northern portion of the forecast area by Thursday morning, with moisture spreading south through the day.
Looking at model soundings, the northwest part of our area will likely see some sleet and freezing rain this evening with the onset of precipitation. Winds will be out of the north/northeast overnight and tomorrow morning until a warm front attempts to lift north causing winds to shift to the east and even the south at CSV.
907 PM CST Wed Feb 23 2022 A mix of rain, freezing rain, and sleet continues across the Mid South. Some places along I-40 have seen some light freezing rain. Areas north and west of I-40 are seeing more sleet and freezing rain. We have already seen thunder snow, thunder sleet, and thunder freezing rain across eastern Arkansas. We have seen reports up to half an inch of sleet in 30 minutes, which has accumulated on the bridges. This would reduce the amount of sleet drastically, but result in freezing rain accumulations approaching a half an inch by tomorrow morning across the winter storm warning area.
221 AM EST Thu Feb 24 2022 Early this morning there is a frontal boundary across the Mid- Atlantic back through the deep south and into the western Gulf of Mexico, with multiple areas of low pressure along the front.
Greater potential for a clear sky across the lowest 5000ft will exist during the afternoon hours. Fortuitous switch from cyclonic to anticyclonic flow trajectories is now taking place at press time as a midlevel cold front pushes southward through Southeast Michigan. Cold drainage flow off the high will result in cold night time temperatures. Did lower mins tonight a degree or two with readings in the lower teens to upper single digits.
344 AM EST Thu Feb 24 2022 Consistent high pressure both surface and aloft remains across the region through the weekend, with rain-free and unseasonably warm conditions continuing. Otherwise, high pressure over the region will keep winds and seas below headlines.
Temperatures across our northwest corner are generally right around freezing. Temps should warm above freezing across the advisory area as we approach sunrise. Winds will be out of the north/northeast overnight and tomorrow morning until a warm front attempts to lift north causing winds to shift to the east and even the south at CSV.
Mid/upper level trough over the intermountain west ejects east into the southern Plains late tonight reaching the mid-Mississippi valley by Thursday evening.
The expected impacts remains the same with bridges, elevated roadways, and exposed surfaces in these areas potentially receiving a light glazing of ice through Thursday morning. We've already seen a round of freezing rain in College Station this evening with reports of ice forming on cars and trash cans. On Thursday night, if freezing temperatures and precipitation align, we could see another round of freezing drizzle/rain.
The deep upper level trough is beginning to push east across the Great Basin this afternoon. After this evening's wave, there should be one more wave late tonight/early Thursday morning associated with the upper trough/cold pool passage.
Below average temperatures will persist through the week with sub-freezing overnight and early morning temperatures across the interior.
Temperatures early this morning are very cold but warmer than previous days, mainly in the single digits above and below zero. High temperatures will mainly be in the low to mid-teens. Temperatures will be very cold again tonight as strong high pressure returns and will be centered just northeast of the forecast near the Nebraska/South Dakota border. As the high pressure pushes east into Iowa Friday, temperatures will begin a gradual warming trend, with highs getting to around freezing. Winds will once again be light as we will be between the aforementioned high pressure to our east and a trough of lower pressure in Colorado and New Mexico.
Temperatures today will change little from yesterday, with highs in the low 20s. There likely won't be enough moisture or focused lift to realize any of the higher amounts advertised by some of the ensembles members. Freezing drizzle no longer appears to be a concern as forecast soundings depict a profile cold enough for only snow.
Conditions will change as a low pressure system tracks just to our south late tonight and Friday. High pressure over eastern Canada today will bring dry weather to the region along with below normal temperatures with highs generally in the mid teens to mid 20s. Combine this with the higher snow ratios.
Below average temperatures will persist through the week with sub-freezing overnight and early morning temperatures across the interior. Several hours of sub- freezing temperatures will likely damage or kill vegetation and any exposed pipes. Temperatures this afternoon will once again warm only into the 50s for most urban areas while holding in the 40s in the higher terrain. As high pressure over the eastern Pacific builds toward the California coast, look for a slight warm-up Friday afternoon. The warming trend will continue into the upcoming weekend as the aforementioned ridge builds eastward and the cold mid/upper level trough responsible our current cold temperatures shifts further east.
336 AM MST Thu Feb 24 2022 Water vapor satellite early this morning shows our main trough axis finally passing through the state. Over the mountains, light orographic snow will continue this morning with winds aloft switching to the west-northwest behind the trough axis. However, increasing subsidence aloft should shut off snow across the majority of the high country in the afternoon hours. An upper level trough will weaken as it slowly tracks southeast across the Central Rockies Friday and Friday night.
The strongest lift shifted to southwest and central Colorado and will reach its peak this evening according to Q derived mid-level omega fields as the low moves to the Four Corners region by midnight. By 12Z/Thursday, the axis of the mid-level trough will be over the Continental Divide so expect forcing to become reduced overnight. Temperatures will be significantly cooler again Thursday afternoon which for most locations will be pretty close to 20 degrees below seasonal norms. The third, weaker trough in this past week's chain of troughs finally moves over eastern Utah and western Colorado. However accumulations remain minimal, a quick 1-3 inches across mainly the higher portions of the Park, Flat Top, Elk, and West Elk ranges.
With RAP soundings showing temperatures as cold as possibly -11C to -12C in this extremely shallow moist layer, sufficient ice nuclei are present to prevent freezing drizzle from falling resulting in these fine ice crystals. /issued 248 AM CST Thu Feb 24 2022/ The center of an upper level low was currently located near the 4- corners early this Thursday morning. Nonetheless, we have gone on the lower side of guidance spread for temperatures this afternoon.
Upper trof axis evident over the cntrl Rockies to Four Corners region will slowly pivot and eject newd this AM. As it does so, there is good agreement among guidance that accompanying low-level cyclone will strengthen as it moves ewd across SD, bringing widespread low-to-midlevel ascent to wrn and cntrl SD now thru the daylight hours. Beyond Friday AM, ridging over the wrn CONUS and deep westerly flow aloft will promote the development of low-level thermal ridging in the lee of the Rockies.
As alluded to in the previous shifts, the main focus today will be on an upper level trough just east of the Rockies and its impact on the region as it ejects northeastward across the central CONUS. However, with soundings showing favorable temperatures aloft and light winds in the lowest levels, believe we still stand a decent chance of seeing snowfall ratios closer to 18-20:1, especially in areas east of I-29.
High pressure will then build across the region this weekend pushing temperatures back into a normal range.
High pressure centered over north central MN will continue to slide east tonight and tomorrow, increasing southerly flow into the Devils Lake basin tonight and the valley into northwest MN tomorrow into Friday.
Light freezing drizzle and sleet dropping visibility in most locations early this morning and should continue through sunrise. Models continue to slow the scouring out of the colder air for today, although should begin to see a little warmer air mass slide northeast into at least Crockett County this afternoon and eventually making a run towards the Concho Valley by sunset. Lows in the lower to mid 20s.
Quite an interesting airmass in place across the area as a warm front is lifting northward this morning. With the warm front lifted to the north will remove rain chances until the late afternoon and generally just in the northwest. Highs today will be in the low 70s in the northwest to low 80s in the southeast. The front will then slide back south tonight as a cold front and will spread rain west to east through the evening and into the overnight.
Cold temperatures will continue through Thursday, then high pressure aloft to the west of the state will bring a warming trend with periods of Santa Ana winds through the weekend. The low pressure system that brought rain and snow to the region is quickly sliding eastward, leaving a wintry air mass behind. Warmer near freezing temperatures are expected near the coast from Ventura County northward. Sunny skies with offshore winds will help temperatures rise into the 50s and 60s today, with cooler 40s for mountain areas. A weak upper level trough swings through tonight, no precipitation is expected, but the trough will likely bring some clouds to the area. Still seeing plenty of sub-freezing to near freezing throughout the area, but will wait to see how this morning's lows turn out before issuing any frost/freeze products for tonight.
429 AM MST Thu Feb 24 2022 Longwave trough slowly fills and breaks off to the east during the short term, with one final lobe wrapping around the trough into western WY today. Once this final lobe rotates through tonight, ridging starts to build across the Intermountain West. The ridge will not build in quickly. Lower elevations will likely finally get into the lower 20s Friday afternoon, helped by some increasing westerly flow at the sfc. Warmer conditions will delay until the longer term forecast. The weekend will be dry as ridging builds across the western US.
642 AM EST Thu Feb 24 2022 Temperatures will remain well above normal through Friday with a dry cold front crossing the area Friday afternoon.
I'm less confident on the northwest extent of the warm front's movement and whether any significant clearing will take place in our southeast counties. Model consensus suggests that the trough discussed above will continue to strengthen as it shifts east-northeastward into the Lower Great Lakes overnight, with a deepening surface wave expected to lift northeastward through the TN Valley early this evening. Showers and perhaps a few thunderstorms will occur both ahead of the low, and in the vicinity of the trailing cold front that should enter northwest AL around 2-3Z and exit our southeastern counties by 10-11Z.
Tonight: Colder area wide with widespread freezing low temperatures across most of the area.
The cold front, which moved through the area yesterday, continues to slowly push farther off the lower Texas coast early this morning. Clouds may thin out briefly to allow highs to reach the low to mid 50s along the Rio Grande River and near the coast this afternoon. A second surge of high pressure/cold front will arrive this evening and bring a reinforcing push of cold air into the region tonight.
Further inland where temperatures are around freezing, radar is indication areas of light precipitation developing to our west and working their way toward our northwest counties. This area is where there will continue to be the potential for a mix of rain and freezing rain through mid morning, so the Winter Weather Advisory remains in effect. Highs should top out in the upper 30s well inland to the low to mid 50s at the coast. We currently expect low temperatures tonight/Friday morning to range from around 30 well north and northwest to the low to mid 40s at the coast. Another shot of frozen precipitation looks possible up north where the lows do fall to near freezing, and another Winter Weather Advisory might be needed. Friday will get a little warmer with highs expected to be in a 44-50 degree range.
348 AM CST Thu Feb 24 2022 Currently across the Mid-South, we have a swath of thunderstorms, rain, freezing rain and perhaps some sleet moving basically along the I-40 corridor. Total freezing rain accumulation up to a half inch in spots is possible.
Northeast low level flow continue to bring a patchy, but remarkably persistent stratus deck over the CWA and the lower Great Lakes early this morning. Friday, high pressure will filter into the area behind the departing snow maker. The weekend will be characterized by plenty of sunshine with much warmer temperatures.
Current trends seemingly indicating our temps likely to be a good bit cooler than previously throught, even though we will see a gradual warming trend throughout the day.
Highs are expected to be below freezing this afternoon in eastern Nevada, with highs in western Nevada climbing into the mid to upper 30's. The system's cold front will bring another reinforcing shot of cold air, and therefore the lows tonight are expected to remain in the single digits. Ridging will build in on Friday, which will bring clearing skies, lighter winds, and the start of a warming trend (during the day, that is). Lows will once again be cold in the single digits on Friday night under the ridge.
Temperatures will remain well above normal through Friday with a dry cold front crossing the area Friday afternoon.
As the mid- level trof pushes northeast through the CWA, chance POPs find their way into our forecast. Temps will peak in the teens today with lows tonight a degree or two cooler than this morning's nadirs. Highs should range from 20s north and west (where snow accumulations are most likely) to near freezing where there will be little to no snow to melt / sublimate.
Areas of light freezing rain/freezing drizzle are currently being observed from southeast Oklahoma into parts of northwest Arkansas underneath a zone of strong moisture transport above the surface. Thanks to warm advection aloft, and slowly warming surface temperatures it is expected that most of the precip today will fall as freezing rain with some sleet/snow mixed in across portions of northeast Oklahoma and far northwest Arkansas where temps will remain quite chilly. Heaviest precipitation should end by mid to late afternoon as the upper level trough axis lift northeast of the area. Some remaining areas of freezing drizzle and snow flurries will be likely into the early evening hours before clouds begin to clear from the west tonight.