Aikyam-Lab/Synoptic-Bench huggingface dataset:
An upper trough extends from western Ontario, across the Dakotas to the main upper low over the Four Corners Region. A secondary upper low embedded in the trough continues to produce areas of light snow over western South Dakota early this morning. At the surface, an E-W oriented band of high pressure is centered over srn SD/nrn Neb. The upper low over western SD will shift eastward and weaken. Westerly winds will become breezy this afternoon and the increasing low and mid- level warm advection will lead to warmer temperatures, with highs reaching the mid 30s this afternoon in the areas with no or minimal snow cover, mainly over northwestern SD. After Sunday, a warming trend will occur as a western CONUS ridge builds and shifts east, allowing downslope westerly flow to spread into the region.
It wouldn't be surprising to see snowfall amounts on the higher end of the forecast range (up to 2 inches in northeast Nebraska). The 2nd round of snowfall is expected in far southeast Nebraska and southwest Iowa as the longwave trough moves across the central Plains. Snowfall amounts in that area range between 2 and 4 inches, but will likely be on the lower end. It'll be difficult to get to the higher end snowfall totals. A tightening of the pressure gradient and an approaching cold front will lead to strong winds on Sunday. Though temperatures will be slightly warmer on Sunday compared to Saturday (today), it won't feel much warmer as the wind chill will result in a maximum feels like temperature in the mid 20s.
Really the only thing of concern the next few days will be low clouds/freezing fog. With ample moisture in the lower levels and light surface winds, conditions certainly favor development although it hasn't been overly widespread just yet. Do expect it to occur however over the next few hours and with temperatures well below freezing, spots of freezing fog are possible. The low clouds and fog, if it transpires, could be slow to burn off after sunrise.
Nighttime temperatures will be below freezing overnight in the rural areas of the San Joaquin Valley as well as across the Kern County deserts.
A new cold front will move into the state late tonight. ushering in much drier and somewhat cooler air to the state.
(Today and tonight) Stronger offshore winds at higher elevations have begun to diminish this morning as the upper low responsible moves out of the Great Basin and into the middle of the country. On the cooler side this morning as well with temps generally about 5 to 10 degrees cooler than 24 hours ago, as of writing.
Cooler temperatures are expected to range in the lower 50s to lower 60s today, as the cooler airmass remains over the area and cloud cover continues to increase over much of the area today. An upper-level trough to the northwest will approach the Southern Plains by this afternoon, generating some lift ahead of it to produce some precipitation chances through the afternoon and evening hours. An accompanying and more potent cold front will begin to work its way through the area tonight into Sunday morning, causing some freezing to near- freezing temperatures across the northern portions of West Central Texas during the overnight hours.
Lows on Sunday morning dip below freezing over southeast New Mexico and the northern Permian Basin with 30s and low 40s stretching southward across the Stockton Plateau and into the Big Bend.
511 AM EST Sat Nov 25 2023 High pressure brings dry weather into Sunday. The next chance for precipitation will arrive Sunday afternoon ahead of a cold front. A high pressure system will provide dry weather for today and Saturday night. This yields marginally slower and stronger cold frontal passage Sunday afternoon/evening for us with perhaps a touch more precipitation than previously forecast.
449 AM CST Sat Nov 25 2023 (Today) A dry and seasonable day is ahead with brief upper level ridging across the southeast U.
(Today and tonight) Water vapor imagery currently shows the center of the upper level trough over the CO Rockies where it is expected to track into the central High Plains later this evening. Ahead of the trough a 120 knot jet will enter the region providing some lift over the FA. KCDS soundings suggest a transition back into wintry mix after midnight, especially for areas of the northern Rolling Plains and far southeastern Texas Panhandle as temperatures drop back below freezing tonight. Precipitation will finally wrap up tomorrow morning as we lose all instability/lift as the upper level trough tracks out of the forecast area.
A cold front continues to move ever so slowly through the region early this morning. We should start to see some weak ridging across the region as we head into the new week. Model guidance is showing a low pressure system developing across the northern Pacific and pushing into California around midweek.
Highs will range from the upper 40s/nr 50 along and north of the parkways, to the low/mid 50s south ans southeast. Closed upper low currently located near the Four Corners this morning will open up and be absorbed by a deepening trough dropping out of Canada later today. As the trough approaches, warm air advection will increase over the area providing some isentropic lift. Temperatures will not be nearly as cold due to the increased cloud cover as well as the warmer air advection. Lows will likely occur earlier in the overnight hours into ranging from the low/mid 30s across southern IN and northern KY, with mid/upper 30s from the Bluegrass and southward towards the KY/TN border.
554 AM CST Sat Nov 25 2023 Short wave ridging and dry air in the low levels will keep things dry today and this evening. A trough over the central CONUS will support a short wave that is progged to eject over the midsouth early Sunday. In the wake of the short wave, high pressure is progged to descend from Canada, which will keep our weather cool and dry for mid week.
A drier air mass will move into the region over the next few days behind a cold trough that continues to push east of the area. Freezing temperatures are likely in areas that have yet to see them so far this fall. Portions of the Las Vegas Valley will see temperatures close to freezing by Sunday morning and these include, Summerlin, Mountains Edge, and Henderson. Mesquite has a much better chance of seeing freezing with that percentage at 75%. With the passage of the trough surface gradients will tighten down the Colorado River where gusts between 25-35 mph will be possible, especially near Laughlin/Bullhead City this afternoon through Sunday afternoon.
Dry with a warming trend early in the week before another storm system brings cooler temperatures along with a chance of showers later in the week. Breezy westerly gradient at times today and cooler. We'll probably clear out early enough for freezing temperatures in colder southern and eastern valleys late tonight into Sunday morning. Most lover elevations in Graham county (including Safford) haven't quite been down to freezing yet, so we issued a freeze warning for the Upper Gila River Valley Sunday morning. Early morning lows will be seasonably cool to start the week, with high pressure pushing afternoon highs up several degrees the first half of the week.
Forecast Details: Middle and high clouds will increase today as two upper troughs approach from the Plains states. The northern stream trough is approaching from the Dakotas, while the southern stream one was over the Southern Plains. The latest model runs show that there should be some interaction between the two troughs, which will likely result in a little more snow than earlier forecast. Highs Sunday will be around five degrees cooler than normal.
Zonal to split flow will return by mid week, with upper level troughing returning for the later half of the week, increasing precipitation chances.
This will likely contribute to a drier boundary layer at least early on before the low levels begin to moisten ahead of the next system due into the region on Sunday. The surface feature appears weak, however, rain chances gradually increase out ahead of the low as stratiform precip develop due to isentropic ascent. The upper level flow is more progressive (generally WSWerly flow), which should help move the surface feature along and allow a cold frontal boundary to move through the region.
538 AM CST Sat Nov 25 2023 (Today and tonight) Water vapor imagery currently shows the center of the upper level trough over the CO Rockies where it is expected to track into the central High Plains later this evening. Ahead of the trough a 120 knot jet will enter the region providing some lift over the FA. KCDS soundings suggest a transition back into wintry mix after midnight, especially for areas of the northern Rolling Plains and far southeastern Texas Panhandle as temperatures drop back below freezing tonight. Precipitation will finally wrap up tomorrow morning as we lose all instability/lift as the upper level trough tracks out of the forecast area.
Overnight lows will drop into the mid to upper 60s across most of the region, excluding the far east coast which will remain in the low 70s. However, if cloud cover lingers, it may keep some of the interior a tad warmer. Temperatures will trend above normal with highs approaching the low to mid 80s.
The upper flow will become southwesterly today ahead of an approaching upper trough and associated cold front. Dry conditions will return by Sunday afternoon from west to east with the passage of the upper trough/cold front. Noticeably cooler air will move into region in wake of the front, with locations behind the front topping out in the 50s for high temperatures Sunday.
The story of the weather for this forecast period begins with an upper level ridge building into the area from the west. At the surface, a weak cold front enters The Treasure State from the north, and, quickly, slips southward across the region. The afore mentioned upper level ridge progresses eastward and becomes the dominant overhead feature for our region.
Locations near the Highway 20 corridor may even see a few 2 to 3 inch reports.
A broad upper trough was centered over the Rockies, while a ridge was anchored across the NERN PAC. Widespread frost/freeze conditions were subsequently occurring across the EKA CWA early this morning, and ridgetop winds gusting from 30-50 mph were locally depicted in regional surface observations.
- Northwest winds will increase behind a cold front Sunday. A stronger trough will skirt along the Canadian border early Sunday, bringing another round of light snow area wide. As the strong cold front moves across Minnesota into Wisconsin, northwesterly winds will increase with gusts of 35-40 MPH expected during the afternoon and evening. By 12z Saturday, a strong cold front will be knocking on the door of AXN and it's in the wake of this cold front that the best chance for snow looks to come for the MPX area.
The upper-level trough will move across our area today, giving us a bit more winter weather before things calm down this weekend. As the trough moves past, there is a possibility of some lingering snow showers as some moisture wraps around the upper low (30% chance for the Palmer Divide and 50% for the southeast plains), which could leave one last trace of snow as the system moves on. Looking at temperatures, highs today will remain below freezing across the plains while the valleys climb into the 30s. Tonight, temps fall back into the low teens to single digits.
By sunrise, low temperatures are expected to dip into the 30s for most Valley locations, with a few areas nearing freezing at the Valley floor. The remainder of the weekend into the early week ahead will see weak upper level ridging building in over the region.
311 AM CST Sat Nov 25 2023 Short wave ridging and dry air in the low levels will keep things dry today and this evening. A trough over the central CONUS will support a short wave that is progged to eject over the midsouth early Sunday. In the wake of the short wave, high pressure is progged to descend from Canada, which will keep our weather cool and dry for mid week.
Persistent high pressure will build as well keeping the region dry and stagnant with little variation in temperatures each day.
Cooler high temperatures are expected today given the cloud cover. The cold front is forecast to move through the area Sunday, with isentropic downglide quickly developing and rain chances ending. Cool and breezy conditions are expected behind the cold front on Sunday.
Otherwise, we should see at least some sunshine today, with high temps climbing into the lower 80s.
- A cold front will bring strong northwesterly winds across the region tomorrow, with gusts up to 35 knots possible. Morning upper air analysis continues to show longwave troughing over the western CONUS, associated with PVA and synoptic scale forcing for ascent across the central Plains. GFS and Euro ensembles are in strong agreement with regards to QPF expected for the remainder of this event, with the highest amounts in far southeast Nebraska approaching 0. A cold front is expected to move into the region from the northwest tomorrow morning, bringing strong gusty winds to the area. The highest wind gusts will be across portions of northeast Nebraska.
(Tonight) Satellite imagery shows ridging over the Eastern CONUS and troughing over the West with a low pressure system spinning across eastern CO. As this upper level trough shifts eastward overnight, the only noticeable weather impact to the Tennessee Valley will be an increase in primarily high level clouds after midnight. Otherwise, a tranquil weather evening is expected with overnight lows dropping into the lower 40s with upper 30s along the higher elevations in northeast AL and southern middle TN.
As a result, current temperatures have finally breached into the lower 80s after being hindered by stratus decks for the last few days. More notably, heights are rising north of Florida as upper level ridging builds in front of a deep layer trough across the western United States. Ridging along the Eastern Seaboard will freshen easterly breezes into tonight.
Meanwhile, an area of low pressure develops in the western Gulf and then shifts eastward along the stalled boundary extending across the Gulf into south FL.
(This evening through Sunday night) In the immediate term, expect precipitation to continue, particularly in the eastern Panhandles in the vicinity of an 850mb cold front as frontogenesis increases in response to an arriving secondary cold front this afternoon. As for precipitation type, while progged low level warm advection has occurred, this is not translating to much warming at the surface, setting up an axis of freezing rain in the southern and central Panhandles, save the SE TX Panhandle where temps have been above freezing. With the Winter Weather Advisory have been previously expanded due to issues on bridges in the southern TX Panhandle, have left headlines as is with this update.
As of 1 PM, satellite indicates the center for this low is somewhere in the vicinity of Regina/Saskatoon.
No adjustments to the afternoon temperatures, but with the cool morning start, afternoon temperatures might end up being a degree or two cooler than current forecast highs in a few areas. However, a disturbance in the northwest flow aloft will sweep a Canadian cold front through the area from around 00Z on the Hi-Line through 09Z into Southwest Montana. /ISSUED 514 AM MST Sat Nov 25 2023/ The story of the weather for this forecast period begins with an upper level ridge building into the area from the west. At the surface, a weak cold front enters The Treasure State from the north, and, quickly, slips southward across the region. The afore mentioned upper level ridge progresses eastward and becomes the dominant overhead feature for our region.
Model guidance has been trending high temperatures this afternoon a little warmer than advertised. The upper flow will become southwesterly today ahead of an approaching upper trough and associated cold front. Dry conditions will return by Sunday afternoon from west to east with the passage of the upper trough/cold front. Noticeably cooler air will move into region in wake of the front, with locations behind the front topping out in the 50s for high temperatures Sunday.
Main impacts across the region this morning have been from freezing fog across the Columbia Basin, particularly the Tri-Cities area.
1213 PM CST Sat Nov 25 2023 Beautiful day is in store across the southeast US as high pressure slides over the region.
A flat upper ridge over the Tennessee valley with surface ridging/wedge east of the Appalachians.
(This evening through Sunday) An upper level trough and cold front are expected to move through the area overnight tonight. The lift associated with the upper level trough will be better to our north, but we'll see light showers here and there this afternoon and evening, prior to the front moving through. Temperatures will drop behind the front, putting some areas in the northern part of our area near freezing. Skies will clear slightly behind the front on Sunday, allowing for some solar heating, which will help keep temperatures slightly warmer than they otherwise would be behind the front.
This will allow for showers to build from the west as the ridge axis tracks east out of our forecast area towards Alabama. PoP chances will be low (ranging between 30-35%) heading into the overnight period with overnight lows in the low 40s north of I-20. The highest amounts will be south of I-20.
The inversion will strengthen through Sunday keeping the valley colder and allowing for stratus fill much of the lower valley by late Sunday evening.
1121 AM CST Sat Nov 25 2023 (Rest of Today) High pressure at the surface will translate eastward across the Ohio Valley today as upper level zonal flow slightly ridges. As a result, mostly clear skies and light winds prevail today as we reach the low 60s.
307 PM EST Sat Nov 25 2023 =================================================================== Key Messages * Not quite as cold tonight compared to last night * Gray, breezy Sunday with patchy light rain =================================================================== As high pressure moves east of Cape Cod and a cold front approaches the Mississippi Valley tonight, surface breezes will gradually start to come out of the south while high clouds stream overhead in broad, fast southwest flow ahead of a deep upper trough moving from the Rockies into the Great Plains. The cold front will push into the middle Ohio Valley Sunday afternoon.
A chilly Saturday morning throughout the Valley with 30s and 40s observed and cooler temperatures across the foothills and mountains.
No adjustments to the afternoon temperatures, but with the cool morning start, afternoon temperatures might end up being a degree or two cooler than current forecast highs in a few areas. /ISSUED 514 AM MST Sat Nov 25 2023/ The story of the weather for this forecast period begins with an upper level ridge building into the area from the west. At the surface, a weak cold front enters The Treasure State from the north, and, quickly, slips southward across the region. The afore mentioned upper level ridge progresses eastward and becomes the dominant overhead feature for our region.
An upper trough is located over the Rockies and ahead of this system, we are seeing an increase in isentropic ascent leading to some light rain and/or drizzle mainly across our western counties. The previously mentioned upper trough will send the next cold front into the Hill Country just before sunrise before making it through the CWA by the noon hour. This front will lead to downsloping in the lower levels of the atmosphere which should lead to drying conditions. Skies are not expected to clear through Sunday night but we should still see lows Sunday night in the 30s to the lower 40s.
- Northwest winds will increase behind a cold front Sunday. A stronger trough will skirt along the Canadian border early Sunday, bringing another round of light snow area wide. As the strong cold front moves across Minnesota into Wisconsin, northwesterly winds will increase with gusts of 35-40 MPH expected during the afternoon and evening.
Otherwise, overnight lows will be slightly warmer over the north because of the cloud cover, but still quite cold over Southwest MT where they will have some clearing. By the end of the week, expect the upper level ridge to break down and to be replaced by a moist westerly flow aloft. However, a disturbance in the northwest flow aloft will sweep a Canadian cold front through the area from around 00Z on the Hi-Line through 09Z into Southwest Montana.
Temperatures this afternoon are mild, in the lower 50s, but will come crashing down behind the cold front as it passes through late this evening (northeast OK) and overnight (southeast OK and northwest AR). Skies will quickly clear by morning allowing for low temperatures to fall near to below freezing in northeast OK, and into the mid 30s elsewhere. Highs will top out in the lower 40s in the north, and mid to upper 40s in the south.
123 PM CST Sat Nov 25 2023 * A cold front will move into the region through the day Sunday, bringing light rain to the region.
Overall the system remain fairly weak with weak omega in the DGZ, where much of the forcing is further aloft with the trough.
With substantial cloud cover sticking around overnight, overnight temperatures will also be a little warmer across inland areas compared to last night. Forecasted low temperatures currently range between the mid 60s just to the west of Lake O to lows in the low 70s across the immediate east coast. On Sunday, the frontal boundary will begin to gradually lift northwards across the area as a warm front. Insolation and warm air advection via southeasterly winds will also result in a warming trend on Sunday with forecast high temperatures in the low to mid 80s across the region.
1035 AM CST Sat Nov 25 2023 Beautiful day is in store across the southeast US as high pressure slides over the region.
(Rest of Today) High pressure at the surface will translate eastward across the Ohio Valley today as upper level zonal flow slightly ridges. As a result, mostly clear skies and light winds prevail today as we reach the low 60s.
Easterly to southeasterly flow at the surface has begun across Central Alabama in response to the ridge of high pressure centered along the eastern seaboard. A mostly clear overnight period should allow for enough radiational cooling to drop temperatures into the lower 40s before clouds increase after daybreak. Mostly mid-level clouds will enter in from the southwest Sunday morning as an upper level trough ejects eastward over the central CONUS.
Despite the waning isentropic ascent this evening, we will see a boost in lift from a cold front moving through the area. The lowest 200mb or so is saturated while the remainder of the atmospheric column is bone dry. As surface temperatures fall this evening, freezing rain may come into the mix for areas off the caprock.
Minor travel impacts are likely with elevated surfaces like bridges and overpasses being particularly slippery. - Winds increase behind a cold frontal passage tomorrow afternoon.
(Tonight through Sunday night) Key Messages: -Cold front to bring cooler temperatures Sunday afternoon. A weak coastal trough will continue to give us a few light showers/drizzle into this evening and move northeast as a cold front approaches Deep South Texas the northwest. On Sunday, a cold font will move through Deep South Texas bringing with it a slight chance of rain, mainly across the lower Rio Grande Valley Sunday afternoon and evening. Tonight will remain fairly mild with lows in the low to mid 60s. Highs will top out in the upper 60s in the northern Ranchlands to the low 70s across the Valley around midday then fall through the afternoon. Temperatures overnight Sunday will be a good 10-15 degrees cooler than tonight with lows in the mid 40s to mid 50s.
Rain chances will begin increasing overnight as a cold front slowly approaches the region. The first will be a fast moving cold front on Sunday that probably won't produce much more than a tenth of an inch of rain.