Aikyam-Lab/Synoptic-Bench huggingface dataset:
1036 PM CST Thu Feb 18 2021 High pressure now stretching out over the Plains will slide east into the region later tonight/Friday. Expect yet another sub-freezing day Friday despite an expected return to more sunshine at most locations as the high sets in overhead. However, Saturday may see several locations possibly top freezing for the first time in 10 days or more, as the high moves off to the east, and winds turn more southerly.
322 AM EST Fri Feb 19 2021 A meridional trough axis will cross the region today, but will be flattening out as it progresses eastward by this afternoon and evening. Latest sfc analysis places a broad area of high pressure stretching from TX to KS and into western MO. NW flow will continue CAA into the region today, which should limit temps from rising above freezing. Pretty substantial pattern change in store for the week ahead favoring much warmer temperatures.
A dry but chilly weekend will be brought about by high pressure.
With good caa mixing in the low levels along with help from a vort lobe from the northwest, kept scattered flurries into the early evening. The issue again tonight will be the low temperatures. Otherwise, it looks like we will finally get a warmer southerly wind on Friday. Temperatures will continue trending warmer as well, peaking Mon/Tue with highs well above average in the 40s and 50s, as the upper-level pattern shifts to northwest-flow.
A widespread snowpack and radiational cooling will allow for overnight lows to fall into the low single digits across the Ozarks region. However, warming will be tough to come by on Friday as a 6 to 8 inch snowpack will keep surface temperatures in check, and likely stay just below freezing in the lower 30s. Saturday looks to be the first day that the area will climb above freezing dating back to February 6th with highs in the lower 40s.
1003 PM EST Thu Feb 18 2021 Weak low pressure will pass by our south and east overnight, and our region will pick up some light accumulating snow and possibly some freezing drizzle. IR satellite imagery shows patchy lower cloud tops of -10c which supports maintaining a chance of freezing drizzle even if this appears to be patchy at best. Some light snow and possibly freezing drizzle will linger into Friday morning before the trough axis moves to our east and winds gain a westerly component behind the system. Lake snows should ramp up on more of a west-southwest flow off Lake Erie Friday night and Saturday with several inches quite possible from the Chautauqua Ridge to perhaps as far north as the Buffalo Southtowns.
Doppler radar and surface observations suggest freezing drizzle and/or light snow showers continue across portions of WV and southwest VA overnight. Surface ridging starts to build from the west as an upper level trough axis enters the OH Valley today. Meanwhile, an upper level trough will cross the area today and tonight, squeezing lingering moisture into light freezing drizzle or flurries. CAA continues tonight with temperatures reaching the lower teens across portions of the Middle Ohio Valley and the northeast mountains, while the mid teens are expected elsewhere. Cold Saturday morning and again Saturday night with high pressure, light surface winds, and snow pack in place.
No major changes were needed for the late eve update as areas of light snow will linger tonight with the encroachment of the cold longwave trough. The Advisory was maintained for the ridges of WV as per additional accumulation potential, albeit light, in addition to the potential for some freezing drizzle given ongoing ascent and low level saturation. Depth of lift will be fairly shallow and near-surface flow will be dry and westerly, so most locations in the forecast area should just receive flurries w/ slightly heavier snow showers occuring to areas north of Pittsburgh and also in the higher elevations where an upslope component will aid lift. Warm advection on the van of the approaching trough will moderate temperature back to the seasonal averages.
A deep mid latitude trough over the Central United States southward into the Gulf of Mexico early this morning will progress quickly eastward but dampen out while lifting northeastward tonight and Saturday. Thereafter, high pressure over the southern plains will move swiftly northeastward and slowly strengthen this weaken, resulting in a brief spell of cooler and drier air.
Did have one small patch of flurries or possibly light freezing drizzle move from east of Bardstown towards Springfield, but not much more than that has shown up recently. Flurries and some patchy very light freezing drizzle can't be entirely ruled out through midnight, but advisory-level impacts are not expected. Observations and reports continue to confirm the returns as snow even as soundings continue to lean towards freezing drizzle along and southeast of a line from Bowling Green to Cincinnati. High pressure builds across the CWA from the west. Partly sunny skies will result, but won't be able to lift temperatures above freezing. The low-level thermal trof will afford us one more cold night on Fri night.
An upper level trough will continue to progress over the central CONUS and on over the eastern CONUS through Friday. At the surface, a cold front has moved east of the local area. From tonight through Saturday, high pressure will build in from the west over the southeast CONUS. High temperatures Friday afternoon will struggle to warm above the mid 40s to lower 50s due to strong cold air advection from north-northwest flow as high pressure builds into the region. Lows Friday night into early Saturday will be the coldest of the near term period, with values in the lower to upper 20s north of I-10 and upper 20s to lower 30s south of I-10. Highs will be a bit warmer Saturday afternoon, as temperatures reach the mid to upper 50s.
The high will then move east of the area on Saturday.
1004 PM EST Thu Feb 18 2021 A low pressure system over northern Florida/Southern Georgia will track northeast towards the South Carolina coast overnight. High pressure will build over the region late Friday through the weekend providing fair weather.
1049 PM EST Thu Feb 18 2021 Currently - An Atlantic ridge extends west southwestwards across the Florida Straits, resulting in gentle southeast breezes across the Keys and surrounding waters. Short Term Update - The lower level ridging will remain near the Keys through the overnight period, but retreat eastwards a bit. The low level inversion is expected to weaken some towards morning and a few showers may be able to develop. A ridge axis across the Florida Straits will retreat eastwards some overnight.
/Tonight/ The evening satellite imagery indicates that the low stratus has cleared the region to the SE, with the low AC and cirrus cigs continuing to diminish as well as the center of the longwave trough continues to shift E from the Srn Plains. Otherwise, AC to cirrus cigs will continue through the first half of the overnight hours ahead of an upper trough over the Srn Plains, with these cigs also giving way to SKC by daybreak areawide.
The back edge of the low AC cigs and cirrus will continue to shift E and diminish with the passage of a longwave trough over the region overnight, with SKC expected by or prior to daybreak areawide. /Tonight/ The evening satellite imagery indicates that the low stratus has cleared the region to the SE, with the low AC and cirrus cigs continuing to diminish as well as the center of the longwave trough continues to shift E from the Srn Plains.
May be related to increasing subside behind mid-level trof. Otherwise mid level trough axis will be the catalyst for a few light snow showers or flurries mainly across northwest and northern portions of the cwa this period. Another wave rounds the base of the trough on Friday afternoon. Friday night through Saturday night: Surface ridging takes hold into at least Saturday morning. the ridge then slides east for the afternoon and overnight.
Temperatures tomorrow are forecast to be a couple degrees warmer than today, and based on today's warmup this seems reasonable. If it not for increasing midlevel and high clouds, I think most of the area would have a good chance to rise near or above freezing. The warming trend continues at the surface and aloft through Saturday as the upper level ridge moves overhead.
The longwave trough axis continued to push east across the Central Plains with rising mid level heights to our west across the Rockies. This will yield a continued warming of the lower-mid troposphere, and this will end up resulting in temperatures on Friday above 32F, commencing the thaw. The ridge axis out west will move out across the western Great Plains Friday night into Saturday, but will dampen out as it does so. This will actually aid in downslope momentum ahead of the next trough, but given how fast the next storm system will be approaching, there really will not be that much time fro the surface wind field and temperatures to respond a great deal, supporting a robust warm-up ahead of the late weekend trough.
Areas of freezing fog are forecast to develop through across eastern NM early Friday morning and will impact KROW with LIFR conditions. Even lower probabilities for freezing fog at KSAF and KFMN early Friday morning, but LIFR conditions can not be totally ruled-out. The eastern plains may see another round of freezing fog and flurries tonight with local reductions in visibility. Warmer conditions are expected Friday and Saturday as breezy westerly winds return.
208 AM EST Fri Feb 19 2021 Low pressure and remaining rain will move out of the forecast area this morning with high pressure and drier conditions building over the region late this afternoon through the weekend providing fair weather.
Therefore, have painted in some patchy fog through the night more or less along the Highway 2 corridor and north. A possibility of fog in the west and relatively warmer temperatures tomorrow highlight the short term forecast. Warmer temperatures expected Friday with low level warm air advection gradually taking place.
(Today and tonight) As the base of an upper-level trough continues to move eastward, a low-amplitude ridge with predominately zonal flow, will enter the area. The only hindrance to diurnal warmer surface temperatures is the remaining snowpack from the winter storm earlier in the week. Even then, temperatures still could reach above freezing in the afternoon. Weak isentropic ascent in the low-levels could allow from some cloud cover, but confidence is higher in mostly sunny skies across the area. For tonight, weak warm air advection will help to keep temperatures in the teens across the area, and in the lower 20s across portions of western-north Texas.
Expect brief rain at the onset of precipitation, changing over to snow as the temperatures fall below freezing. Expect 1 to 3 inches across the lower valleys with 3 to 8 inches across the mountains with this system. The bulk of the snowfall is still on track to end by early Friday morning, but will persist in the higher elevations through mid-morning. A cold front will be accompanied by valley rain/snow showers and mountain snow showers as it moves across the area from northwest to southeast from Friday afternoon through Friday night. A weak upper trough moving through a northwest flow aloft will support snow showers in the higher elevations on Saturday.
A wave of low pressure is moving NE along the boundary and emerging off the NE FL coast. High pressure will build in from the west today and remain the dominant weather feature through the remainder of the short term period.
955 PM MST Thu Feb 18 2021 WV imagery this aftn shows broad troughing over much of the cntrl CONUS, with an associated polar jet as far south as the Gulf Coast. More substantive trof approaches on Saturday. Though ensembles continue to suggest a fairly low potential of high QPF in any one location, more ensemble solutions now favor the formation of a heavier band of snow as the positively tilted trof approaches. The tilt and track of the trof will support a zone of roughly west-to- east oriented DPVA and deformation from Saturday morning thru the night, tracking ewd with time. Additionally, strong low-to-midlevel fgen will likely transition sewd with time as low-level cyclone strengthens, with the primary area of snow following, so duration could end up being limited.
/issued 210 PM CST Thu Feb 18 2021/ Upper trough swings across TX today and pushes off to the east. As it does high pressure will build in from the west and remain over the area through Saturday.
It will be warmer on Friday, then cooler Saturday as a disturbance turns flow back onshore with gusty westerly winds over the mountains and deserts.
Tonight Through Saturday A strong upper low pressure system located in the upper Midwest will move across the Great Lakes Friday and into New England Saturday. A large upper ridge will move into the Rockies Friday and to the Plains Saturday.
351 AM EST Fri Feb 19 2021 Leftover pockets of light snow and freezing drizzle today will give way to accumulating lake snows mainly southeast of the lakes tonight and Saturday.
Friday will be slightly warmer, but still well below normal with highs in the low to mid 20s. A broad upper level trough continues to influence our weather through the short term. Highs tomorrow will again reach into the low to mid 20s. Saturday will start a gradual warming trend as the upper trough of cold air finally begins to shift toward the East Coast.
956 PM MST Thu Feb 18 2021 Scattered flurries across northern areas associated with a weak disturbance embedded in the complex upper trough over the central plains will dissipate early as the trough begins to move away from the area tonight. Upper ridge will build in from the west on Friday but flatten into more of a northwest flow by late in the day. However, it will allow temperatures to warm above freezing in most locations, with the possible exception of lower elevations along the Republican in southwest Nebraska, including McCook. Main upper ridge axis will move across Friday night and Saturday, further moderating temperatures. A brief period of breezy/windy northwest winds possible late Saturday night behind associated cold front.
125 AM EST Fri Feb 19 2021 Weak low pressure will pass by our south and east overnight, and our region will pick up some light accumulating snow and possibly some freezing drizzle. IR satellite imagery shows patchy lower cloud tops of -10c which supports maintaining a chance of freezing drizzle even if this appears to be patchy at best. Some light snow and possibly freezing drizzle will linger into Friday morning before the trough axis moves to our east and winds gain a westerly component behind the system. Lake snows should ramp up on more of a west-southwest flow off Lake Erie Friday night and Saturday with several inches quite possible from the Chautauqua Ridge to perhaps as far north as the Buffalo Southtowns.
1249 AM EST Fri Feb 19 2021 Steady snow will end tonight as low pressure moves east. Cold temperatures and snow flurries are expected Friday as high pressure advances from the southwest. Dry weather and gradually rising temperatures are forecast for the weekend as the high tracks across Kentucky and West Virginia. Flurries and freezing drizzle will still be possible through the overnight hours. High pressure in the southern Plains will begin to slowly move northeastward into the Midwest on Friday. Mid-level flow will gradually shift more towards the northwest with a s/wv trough propagating through. There does appear to be a trend towards slightly warmer temps compared to what has been previously shown - mainly due to greater cloud coverage lingering across the fa.
920 PM CST Thu Feb 18 2021 The trough axis remains to our west this evening but will swing across the Mid-South during the day tomorrow. Only minimal changes were made to most forecast parameters, but patchy freezing fog was added in the Tennessee and Tombigbee River Valleys. We don't anticipate any significant issues from the freezing fog but road conditions will remain pretty abysmal across much of the CWA, especially on residential streets and secondary roads. High pressure will start to build into the region tonight with dry weather expected. High pressure will remain over the region for Friday and Saturday keeping things dry across the Mid-South. Temperatures will be a little warmer on Friday with highs in the mid 20s to mid 30s. Saturday should be warmer as winds become more southerly with highs in the lower 30s to mid 40s.
More sunshine will occur today which will allow highs to warm into the upper 20s to the lower 30s. Most locations will likely remain at or below freezing for yet another day. Warm air advection will kick in on Saturday bringing warmer temperatures to the area.
200 AM MST Fri Feb 19 2021 Scattered flurries across northern areas associated with a weak disturbance embedded in the complex upper trough over the central plains will dissipate early as the trough begins to move away from the area tonight. Upper ridge will build in from the west on Friday but flatten into more of a northwest flow by late in the day. However, it will allow temperatures to warm above freezing in most locations, with the possible exception of lower elevations along the Republican in southwest Nebraska, including McCook. Main upper ridge axis will move across Friday night and Saturday, further moderating temperatures. A brief period of breezy/windy northwest winds possible late Saturday night behind associated cold front.
At the same time, a pocket of cooler air aloft at 850mb combined with the increased heating from the solar angle this time of year will allow diurnal snowshowers to impact much of the UP. Upper air pattern consists of a 500 mb trough in the western U. and a trough over the east 12z Sat. The trough moves into the plains 12z Sun and into the upper Great Lakes by Sun night. In the extended, the GFS and ECMWF show a 500 mb ridge across the western U. and a trough across the eastern U. Troughing moves into the Rockies 12z Wed. This trough heads east, but misses the area for Thu and Fri.
Latest RAP analysis places the cold front just E of the S Appalachians, but the colder air has been slow to cross the Cumberland Plateau into our region. At the same time however, forecast soundings show the low-level moisture beginning to erode after 06Z, so expect any light accumulations to be confined to the higher terrain of the Plateau and E TN/SW VA mountains late tonight. Garuckas Chattanooga Airport, TN 29 43 22 47 27 / 20 0 0 0 0 Knoxville McGhee Tyson Airport, TN 29 39 20 42 25 / 30 10 0 0 0 Oak Ridge, TN 28 40 18 42 25 / 30 0 0 0 0 Tri Cities Airport, TN 31 38 18 38 23 / 40 10 0 0 0.
The highest terrain of the Park Range generally east and north of Steamboat Springs are likely to see a few a quick few inches of new snowfall on Friday. Models were in much better agreement with the evolution of the split, mid-level trough forecast to move over the area on Saturday. Saturday morning, the strongly tilted trough moves over the northern Great Basin and begins to generate light snow over the Uintas, Elkhead and Park ranges with isolated to scattered snow showers over the Flat Tops and the central Colorado mountains. Expect showers to increase and spread south during the afternoon as the trough approaches the Rockies during the afternoon. Snowfall becomes driven by orographic flow and instability late Saturday night as the trough axis moves east of the forecast area.
Today will be cold as high pressure slides in from the west. High pressure will be sitting right over the area tonight and with partly cloudy skies, calm winds, and snow cover still on the ground, temperatures will tank into the teens once again.
Higher-res models are in excellent agreement w/ 48-hour totals approaching 12 inches over the high peaks, which makes sense given strong dynamic support and favorable orographics.
RGB satellite imagery showing the low clouds rapidly diminishing from the north early this morning and expect this trend to continue through the rest of the morning.
402 AM MST Fri Feb 19 2021 Areas of light snow and blowing snow will affect much of the region today, as warmer air tries to move into the area.
Southerly flow on the backside of this high will help to initiate low lvl warm advection and lead to a bit warmer day across most of the forecast area. A warm front will move into the western Dakotas by late today into tonight. The warming trend is still set to continue into the start of the weekend as the low level warm advection pattern persists. Highs above freezing will be more probable west of the James valley by Saturday afternoon. When the period opens, an area of low pressure is moving across the central plains, mainly south of this CWA.
Upstream, decaying ridge axis aloft is progged to spread eastward into the plains later today, in response to a deepening low pressure system entering the Pacific Northwest. Decent downsloping warmer air from western KS at h850 couple with mostly clear skies should carry highs today above the freezing mark for the first time in 2 weeks! Readings are warmest towards central Kansas where low 40s are possible while low to middle 30s are seen elsewhere. Given the forecast lows in the teens, patchy dense freezing fog may cause isolated slick spots on roadways.
Temperatures this morning are cold and that will not change much over the next 24 hours as much of the area will remain below freezing again today. High pressure will be in place over the area today and Saturday. some of the short rang guidance is pointing to freezing fog overnight into Saturday morning. Will have to watch this today as a Freezing Fog Advisory may be needed.
Today will be much warmer than the past several days but still close to 15 degrees below normal for maximum temperatures. with a few areas over lower Acadiana potentially reaching the lower 50s. The cold air mass will continue for one more night as high pressure will settle over the area. Hence, one last night of subfreezing temperatures will be forecasted with the potential for hard freeze north of I10 corridor.
Meanwhile, dry and stable air will spread over the local region as the high pressure moves slowly eastward over the eastern Texas later this morning. Therefore, sunny skies with highs in the low to mid 50s are anticipated for today. However, the clear skies and light winds this evening will enhance the radiational cooling dropping the temperatures below freezing again for a few hours in portions of the inland areas.
The axis of this jet shifts south through tonight as a closed upper low moves down to the southwest corner of Oregon late tonight, before opening to an upper trough and moving to the southeast of the forecast area by late Saturday morning. Showers taper off quickly as an upper ridge nudges into the west coast.
(Today and tonight) Very cold temperatures across the area this morning, with 3 AM readings mainly in the low to mid teens, although Abilene and Sonora are reporting five degrees and seven degrees respectively. We finally get to see the sun again today, along with temperatures climbing above the freezing mark as south to southwest winds return. Will undercut guidance temperatures a few degrees today, due to residual snow cover, with afternoon highs mainly in the lower 40s. Temperatures will be cold again tonight, but not as cold as what we are currently seeing this morning, with lows in the low to mid 20s.
Current surface analysis places trough to the lee of the Rockies and high over the southern plains into the midwest. Upper level analysis places trough through the midwest and compact ridge working into the northern plains, with short wave trough right behind it. For today and tonight, fog will dissipate by mid morning, with quiet weather then expected through mid-day as upper ridge to the west passes over. High temperatures are expected to be a fair amount warmer over most locations, particularly the southwest where many locations are expected to push into the lower 30s. Later in the afternoon into the evening the aforementioned short wave behind the ridge continues its approach.