Aikyam-Lab/Synoptic-Bench huggingface dataset:
Warm and moist southerly flow will persist across our area today as deep layer ridging remains in place to our east and a potent upper level trough covers the western half of the CONUS. As this pattern remains relatively stagnant, a front will become nearly stationary well to our northwest from the lower Mississippi Valley into the Ohio Valley region. Another warm day is expected with highs from the lower-mid 80s inland and upper 70s along the coast.
Tonight temperatures should be a bit higher than the previous night and thus wind chills remain in the 10 to 20 below range, just warmer than the 25 below criteria for advisory conditions.
A tightening pressure gradient between departing high pressure and developing plains low pressure will likely cause wind gusts to increase to Small Craft Advisory levels Thursday night. other issue is remaining standing roads in low areas, along with freezing of the water with the colder temperatures. other issue is remaining standing roads in low areas, along with freezing of the water with the colder temperatures.
At 4 am this morning, a cold front was just starting to enter northwest Middle Tennessee, accompanied by showers and isolated thunderstorms. As our cold front stalls out over extreme southern and eastern parts of the Mid-State late today, it will set the stage for some locally heavy rainfall in areas along and north of the boundary.
A broad trof is pushing through the state this morning. The trof passage will help warm temperatures a few degrees today over yesterday with teens for most locations and a few single digits northeast. Clearing skies and weakening winds behind the trof passage will let temperatures drop below zero in most locations tonight, though mainly in the single digits below zero. Area remains under the deep trof in place across the western U.
trough will remain across the region with colder than normal temperatures therefore expected. Overall, a cold though quiet weather regime will persist across northeast Montana into the end of the week with the deep upper trough only gradually translating eastward.
The potential is there for additional activity to develop during the day today as a slow moving cold front currently across our N and NW counties possibly becomes a focus as it works its way toward the coast. It is also quite possible that the cold front could stabilize a large part of the Watch area to prevent any significant additional development. Cold front is forecast to sag close to the Houston Ship Channel-Matagorda Bay prior to sunset.
Anomolously strong mid level ridge with 500 mb heights to 595 DM will continue off the Carolina coast and extend to west central FL through the afternoon. Low level ESE/SE flow will average around 15 knots in the lowest few KFT and keep any late west coast sea breeze pinned near the beaches or more likely just offshore. The pressure gradient associated with the high will remain tight enough to keep any sea breeze component just offshore today, but as the high weakens on Thursday better chances for the sea breeze component will increase.
The upper trough over the West Coast extending into Canada will interact with the 595 DM high over the Atlantic to keep moderately strong NW flow over the state.
848 AM MST Wed Feb 21 2018 Temperatures have warmed allowing wind chill readings to also be warmer and above the needed criteria. This first one will trigger light precip to start after 06z Thursday and taper off from SW to NE as the H5/H7 trough swings across the area. Up to a half inch of light snow is possible with even a trace of freezing rain based on latest models.
656 AM EST Wed Feb 21 2018 A cold front will move across the area this morning bringing widespread showers and cooler temperatures. Low pressure tracking just south of the region tonight into Thursday will result in more widespread precipitation. Sharper decrease in temperatures will come as a cold front just entering the forecast area moves through this morning. The other concern is that temperatures north of I-70 will likely fall to or just below freezing. This would result in a period of freezing rain. Forecast lows are a multi-model blend while highs leaned towards cooler guidance.
Therefore, the precip may change over to freezing rain. There is one problem, the dendritic layer will eventually become unsaturated so there might more freezing drizzle than rain. The eastern zones and/or where it snows might see cooler high tomorrow than compared to areas that miss out on precip entirely. This second system will be much warmer than the current system. Another cool down is expected in the wake of the second system as it exits the area and cool high pressure prevails.
This first one will trigger light precip to start after 06z Thursday and taper off from SW to NE as the H5/H7 trough swings across the area. Up to a half inch of light snow is possible with even a trace of freezing rain based on latest models.
A transition to freezing rain towards daybreak areawide is expected as the warm nose develops. NAM however is much quicker with the mid level dry air and would only suggest freezing drizzle or light freezing rain.
High pressure centered over north central Nebraska at 08Z will shift east toward the lower Great Lakes today and give the area a mostly sunny but cold day today before clouds and precip return tonight and Thursday. Soundings and RH progs suggest mid levels will be drying out between 06Z and 12Z Thursday in the south so some freezing drizzle may replace the light snow in that area during the early morning. A stronger surge of dry mid level air is indicated to move into southeast Nebraska and southwest Iowa Thursday evening with freezing drizzle becoming the dominant precipitation type there at that time while a mix of light snow and freezing drizzle continues in the north.
424 AM MST Wed Feb 21 2018 Current surface analysis shows high pressure centered over northern NE, with arctic airmass in place across the region. Clouds will increase tonight as southwesterly flow aloft develops ahead of digging western US trough.
808 AM EST Wed Feb 21 2018 Rain returns today with the passage of a cold front. Quick update to adjust hourly temperatures and bump up wind gusts along the cold front as it begins to cross late this morning and through the afternoon. Cold front will cross most of the area this morning, clearing the southeastern ridge by late this afternoon. The cold front will stall just to the south of the area tonight, allowing additional moisture to get pumped into the region in the southwest flow aloft. Models are still showing some disagreement in the temperature structure, and have continued mention of snow and freezing rain, which is dependent on whether the low-level cold air manages to drive far enough to the south.
Part;y to mostly cloudy skies will prevail for the remainder of today, with cold high temperatures in the lower/mid 30s for the lower elevations and mainly 20s for the mountains.
525 AM CST Wed Feb 21 2018 Cold front at 09z is through all but the KHOP area.
A trough of low pressure will likely persist over the West Coast through the next seven days, supporting below normal temperatures with showers possible at times. Latest satellite imagery indicated a trough of low pressure dropping southward along the California coast. Some increases in mid and high level have moved into the region in the westerly flow out ahead of the trough. Low temperatures so far this morning have been a bit warmer than expected, especially near the coast. Some of the other frost/freeze products have been adjusted to account for the warmer temperatures (see the NPWLOX product for details). Another cool day on tap today due to the trough overhead with temperatures again struggling to reach 60 across many coasts/valleys and cooler inland.
Model forecast soundings show primarily snow at the onset, but a loss in dendritic moisture into the overnight hours and on Thursday forces a transition to freezing drizzle at times. Our current forecast has snow totals near an inch from Ord to Fullerton, but this could be higher if we see more saturation, or even less if the band shifts or we see more freezing precipitation.
Skies are clearing from the northwest with some high clouds as high pressure moves in. Area temperatures have dropped into the mid teens far NW to the lower 20s in the southwest. However, as warmer air works into the area the snow will mix with freezing drizzle and then eventually drizzle for areas south of highway 30.
A cold front currently stretches from near Pittsburg to the south and east to near Nashville southward to just inland along the Texas coast. Chattanooga Airport, TN 78 62 78 59 / 30 50 30 20 Knoxville McGhee Tyson Airport, TN 76 60 76 59 / 40 40 50 20 Oak Ridge, TN 76 60 74 59 / 50 60 60 30 Tri Cities Airport, TN 76 56 73 54 / 40 30 50 30.
/issued 321 AM CST Wed Feb 21 2018/ Currently cold front and leading edge of heavier convection is snaking it's way from northwest Tennessee back into the northern Memphis metro and east central Arkansas. to the low 70s in the south and east.
In addition, freezing rain will be possible this morning and into early this afternoon, at KSJT and KABI. The potential for freezing rain will return overnight, with precipitation chances continuing and temperatures falling below freezing.
Given the better performance of the short-range models with mentioned cold front the past few nights, the near-term forecast will lean closely to the NAM/HRRR. The warmer temperatures aloft will allow for a transition from snow/sleet to freezing rain. Another round of light freezing rain could be possible Thursday morning before we warm above freezing.
930 AM EST Wed Feb 21 2018 Lcl WX pattern remains largely unchanged with a strong high pres ridge over the W Atlc extending acrs the Deep South as the dominant feature. If anything, ridging overhead has increased as the 24hr RAOB trend shows the base of a sharp mid lvl subsidence inversion has dropped from arnd H70 to H85 with PWat values btwn 1. Marginal to poor boating conds this aftn as a strong high pres ridge over the W Atlc maintains a gentle to moderate E/SE acrs the region.
Precipitation type may vary, but generally should range from mostly freezing rain in the south central/southeast portion of the state to freezing rain and sleet from western north Texas and southwest Oklahoma northeastward through central Oklahoma and into north-central Oklahoma. In northwest Oklahoma, the precipitation may be predominately snow to start, and then sleet and eventually freezing rain will become common throughout the day. Similar to last night, brief periods of moderate to heavy freezing rain and/or sleet can't be ruled out Latest radar mosaic shows a northward shift of precipitation across north Texas with heavier precipitation now approaching the Red River.
433 AM CST Wed Feb 21 2018 At 4 am this morning, a cold front was just starting to enter northwest Middle Tennessee, accompanied by showers and isolated thunderstorms. As our cold front stalls out over extreme southern and eastern parts of the Mid-State late today, it will set the stage for some locally heavy rainfall in areas along and north of the boundary.
Satellite trends show a classic isentropic precip regime underway early this morning behind a sharp cold front plunging into the Big Bend. Model soundings are largely conducive for sleet given sub-freezing layers of 2000 to 3500 feet thick beneath a stout warm nose, so have removed earlier freezing rain wording (even in our SE zones) as this scenario is looking too conditional. A reprieve from wintry precip is likely tonight behind this impulse, but on its heels will be a higher altitude and weaker trough arriving in SW flow by Thursday morning. Opted to lower PoPs considerably given this trend and WPC's lower QPF values, but have retained mention of freezing rain and light icing potential generally off the Caprock Thursday morning before temperatures recover to above freezing in the afternoon.
For tonight, will see much cooler temperatures again relying on the Hi Res models for the guidance rather than GFS on 24 hour old ECMWF/Canadian. Sustained moderate north wind on Thursday with coastal trough offshore.
335 AM MST Wed Feb 21 2018 Current surface analysis shows high pressure centered over northern NE, with arctic airmass in place across the region. Clouds will increase tonight as southwesterly flow aloft develops ahead of digging western US trough.
Forecast is on track with generally rain-free conditions and temperatures currently approaching 80 degrees topping out in the low to mid 80s this afternoon. /issued 345 AM EST Wed Feb 21 2018/ TODAY THROUGH THURSDAY: South Florida weather will continue to be driven by the large upper level ridge now centered to our northeast off the coast of the Carolinas. The ridge is forecast to strengthen over the next 24 hours as it becomes more east west oriented across Florida. The eastern side of the region will hold a little closer to normal in the low to mid 80s.
625 AM CST Wed Feb 21 2018 Only changes made to the forecast was to match current winds and temps as high pressure in control with westerly winds bringing wind chill values around criteria level of 25 below in E ND. Tonight temperatures should be a bit higher than the previous night and thus wind chills remain in the 10 to 20 below range, just warmer than the 25 below criteria for advisory conditions.
538 AM CST Wed Feb 21 2018 A strong high pressure at the surface was centered over Nebraska early this morning, with a ridge extending northeast to over northern Minnesota. Aloft, there is a trough axis out over the Rockies with ridging east, and a strong upper level jet extending from Texas to the western Great Lakes. Temperatures to remain below normal today and tonight with the ridge overhead and fresh snow cover, with the airmass offsetting the late February sunshine. Tonight the ridge and clear skies is going to make for good radiational cooling conditions.
The next short wave trough, currently in BC, is of greater concern to our CWA as it moves in from the NNW late tonight and Thursday. That trough will bring light snow to most of our zones, and with the ground already cold, the snow will stick to the roads. Light snow will continue Thursday, mainly on the Idaho side, as the trough closes off a low in eastern Oregon. Winds will be light southeast today, increasing to light to moderate southeast tonight and Thursday morning, then shifting to northwest behind a cold front later Thursday.
Anomalously strong mid level ridge with 500 mb heights to 595 DM will continue off the Carolina coast and extend to west central FL through the afternoon. Low level ESE/SE flow will average around 15 knots in the lowest few KFT and keep any late west coast sea breeze pinned near the beaches or more likely just offshore. The pressure gradient associated with the high will remain tight enough to keep any sea breeze component just offshore today, but as the high weakens on Thursday better chances for the sea breeze component will increase.
Issued by National Weather Service JACKSON MS 857 AM CST Wed Feb 21 2018 Latest rap and satellite imagery showed the forecast area under the influence of a strong midlevel ridge off the Atlantic Coast with southwest flow aloft. /17/ The NAM/SREF and even the GFS all pivot the cold front back northwest a bit on Thursday morning, and thus the convergence needed to support widespread precipitation.
The low pressure system stalls momentarily over Oregon causing precipitation to move back into north central Idaho by Thursday morning. Thirty-six hour snowfall total forecast support 1 to 4 inch accumulations across most valleys with 8 to 18 inches throughout the higher terrain.
other issue is remaining standing roads in low areas, along with freezing of the water with the colder temperatures. other issue is remaining standing roads in low areas, along with freezing of the water with the colder temperatures.
On the larger scale, GOES-16 WV imagery and global model initializations shows broad upper level trough over the western US with a deep surge of moisture extending from the Gulf of Mexico through the Great Lakes region.
610 AM CST Wed Feb 21 2018 High pressure centered over the state will gradually drift east today with low level flow remaining westerly. High pressure continues east overnight and flow becomes southerly ahead of the next system. Energy aloft will continue to dive south along the west coast, thus keeping a western conus trof pretty much in place. Pcpn type should favor snow, but patchy freezing drizzle also looks possible mainly before and after the main event has occurred.
602 AM EST Wed Feb 21 2018 After another mild night, a cold front crosses the Middle Ohio Valley today. A mild morning expected today, with southerly flow ahead of an approaching cold front. The cold front will move through from west to east this afternoon and evening. Showers, heavy at times, will continue on Thursday as wave of low pressure moves northeast through the area along stalled frontal boundary.
Record high temperatures are expected at all four climate sites today as a very anomalous upper-level ridge remains parked just off the coast of the Carolinas.
413 AM CST Wed Feb 21 2018 An upper level ridge is currently centered north of the Bahamas and will remain there through most of this week. The west side of this high pressure extends into the Bay of Campeche. This extent of coverage will change throughout the week based upon intrusion of an upper trough to the northwest.
Very benign short-term portion of the forecast with arctic high pressure moving across the region and upper level flow transitions from zonal to slightly southwesterly with a much drier atmosphere. Surface analysis shows the center of high pressure over the Dakotas and this high pressure airmass is expected to shift easterly over southern Minnesota and into the Great Lakes through Thursday morning. While the high pressure area shifts off to the east tonight, a weak cold front will drop in from the northwest.
Western Atlc High pressure ridge axis remains extended across NE FL/SE GA and steering flow out of the south will continue above normal temps with near record highs in the lower to middle 80s over inland areas. Overnight lows generally in the lower 60s. Any potential for sea fog will be across the remaining cooler waters along the SE GA coastal areas.
/issued 345 AM EST Wed Feb 21 2018/ TODAY THROUGH THURSDAY: South Florida weather will continue to be driven by the large upper level ridge now centered to our northeast off the coast of the Carolinas. The ridge is forecast to strengthen over the next 24 hours as it becomes more east west oriented across Florida. The eastern side of the region will hold a little closer to normal in the low to mid 80s.
Cold front continues to push southward into the area. Cold front was located from Victoria to south of Pleasanton to north of Uvalde then down to Eagle Pass. ARW/NAM shows this portion of the cold front will surge southeast through the Brush Country this afternoon.
448 AM CST Wed Feb 21 2018 Early morning weather map shows high pressure centered off the sern CONUS coast, maintaining a very moist srly low-level flow over the forecast area. A strong cold front is noted stretching from the Ohio Valley through the mid-South to ern TX, with temps behind it running in the 30s/40s. Water vapor imagery shows ridging over the sern CONUS with a digging trof noted over the wrn CONUS. A fairly wet period remains in the cards this morning, led off by the aforementioned cold front. With ridging progged to hold steady off the sern CONUS, the front is expected to stall just to our nw/n later today. All in all, everyone has elevated POPs at some point today, with the lowest being good chance POPs across lower Acadiana.
The potential for freezing rain will return overnight, with precipitation chances continuing and temperatures falling below freezing.
Temperatures remained warm overnight in a well mixed boundary layer with readings in the low to mid 80s. Southern extent of the westerlies is expected to remain just to the north of Kansas today as a broad upper high stretches from the Rockies to the Carolinas. Also low level jet will be out of the southwest and mostly parallel to the low level boundary in Kansas. Lows again will be warm with lows from the lower 70s north to the upper 70s along I-70 and south.
Today Will Likely be the Hottest Day so far this Summer The center of the upper level ridge of high pressure is right over the Ozarks Region this morning.
Deep layer ridging from the Atlantic will reside across the Deep South through the period as a tropical wave tracks by to the south. The highest amounts will be found in the south.
A cold front will trigger more widespread showers and thunderstorms Wednesday night into Thursday.
Warming temperatures expected today as models continue to indicate the area of high pressure will work to reamplify over the next couple days.
Upper ridge begins to build back into Montana today. The ridge continues to build into the forecast area tonight and Thursday. Once again an upper level ridge will be in place over the Northern High Plains Thursday evening.
Noticeably cooler weather can be attributed to an upper level trough and associated surface front. The amplification of high pressure aloft over the CONUS southwest will bring very warm air into the state.
Mainly dry, and slightly cooler weather will arrive for the weekend. A narrow and nearly east/west 925-850 mb Theta-E ridge over northwestern PA (and also developing across the southwest corner of the state including the Laurel Highlands) will be areas of focus for some slow moving heavy showers and a few low-topped tsra through the mid morning hours. The lows will be some 5-10 deg warmer than normal. trough in response to strengthening upper level ridge centered over the Four Corners states.
454 AM EDT Wed Jul 12 2017 A very warm day is in store for the region as a warm frontal boundary lifts north today and precipitation chances diminish.
500 AM MDT Wed Jul 12 2017 Updated Aviation Discussion A pronounced warming trend begins across the area today as high pressure ridging builds across the region, with high temperatures Thursday through the weekend reaching the 90s to possibly 100+ over parts of the plains. A pronounced warming and drying trend will begin today as high pressure ridging aloft builds across the region. CC The unseasonably strong ridge over the western US early in the period will gradually be flattened with time over the weekend as an upper level low over the NE Pacific gradually works inland across WRN Canada.
Broad flat ridge aloft stretching from the southern high plains to southeast US coast will persist for a few more days slowly weakening and shifting west by the weekend.
A warm front extended from the low across central MN and central WI. More showers and a possible storm will develop as the upper low approaches later this morning and will come to an end Thursday morning as the upper trough finally moves to the east and is replaced by high pressure aloft and at the surface. Brisk east winds will keep temperatures much cooler near Lake Superior today.
At the same time, an inverted upper level trough will be located to the west over eastern Mexico. The weather pattern remains fairly similar tomorrow with trough still located to the west.
Short term guidance continues to advertise a regime of increasing low to mid-level moisture advection today, as southwesterly winds strengthen on the western periphery of an anticyclone approaching from the east. Although this activity may initially develop both in the vicinity of a lingering outflow boundary in northwest AL and across the higher terrain of the east, weak vertical shear suggests that storms will be unorganized with additional development along outflow expected through the afternoon/early evening. Max temps should be a few degrees cooler than yesterday based on the introduction of more clouds and precipitation, but heat index values will still peak in the 98-102 degree range for many locations.
The rest of the forecast features a building ridge across the area, with gradual warming 850-700mb temperatures.