Aikyam-Lab/Synoptic-Bench huggingface dataset:
(This evening through Monday night) The latest 28/16z RAP H500 analysis indicates a low pressure system is currently located across south central Arizona and is steadily moving off to the east. The trough will begin to slightly weaken and lift northeast on Monday over Arizona/New Mexico. If any showers do form, very minimal rainfall would be expected due to drier air in the lower levels of the atmosphere.
1119 AM EDT Sun Sep 28 2025 Weak high pressure builds in behind departing low pressure today.
Clear skies & calm winds have lead to prime radiational cooling conditions overnight, with temperatures falling into the low 40s across central Minnesota & western Wisconsin. Very warm conditions are expected this week as ridging amplifies over the Upper Midwest & Great Lakes region. Precipitation chances will continue to be negligible with the strong ridging overhead, so we'll likely have to wait until at least this weekend when the jet amplifies over the US-Canada border & flattens out the ridge. With high pressure remaining to our east, we'll maintain south to southeast winds the whole period.
Midday surface map indicated a ridge axis stretched from the central Great Lakes southwest to TX.
Upper low is currently located across north central AZ and is continuing to move towards the east-northeast this afternoon.
Temperatures are in the low to mid 70s and are on track to reach the lower 80s this afternoon. Persistent ridging will keep this period of calm over our region through the early workweek.
Early this afternoon, water vapor satellite showed a broad upper ridge centered along the lower and mid MS River Valley. A filling cut off upper trough was located across the Great Basin and southwestern US.
Ensemble and deterministic guidance has this ridge overhead through much of the week. By the end of the week, ensemble guidance shifts the ridge axis to the east and most (about 85%) of the ensemble members support the ridge flattening out a bit and a longwave trough approaching from the west, however the strength and timing of this trough are quite uncertain at this time. VFR conditions are expected for much of the TAF period outside of a 20-30 percent chance for shallow IFR/LIFR fog east of the Mississippi River and IFR stratus within the Mississippi River Valley between 09-14Z--the lower confidence driven by stronger winds just off the surface.
Look for overnight lows tonight and tomorrow to range in the low to mid-60s, with afternoon highs on Monday ranging in the mid to upper- 80s.
(This evening through Monday night) An upper level ridge extends from northern Mexico to the central Plains this afternoon. Temperatures this afternoon are in the 80s and most of the area will have highs in the lower 90s. An upper level trough will move into western TX tonight into Monday and this will bring some mid to upper level cloudiness over the Southern Edwards Plateau.
1233 PM EDT Sun Sep 28 2025 High pressure will lead to dry and mild conditions through the week.
1208 PM CDT Sun Sep 28 2025 - Dry weather and warmer than normal temperatures are expected through the start of the work week. - Disturbed weather over the Southeastern US this week could bring a chance for cooler weather and possible rain later this week. Today and Tonight: Warmer than normal and dry through the period. Ridging surface and aloft will strengthen over the region from the northwest through tonight.
209 PM CDT Sun Sep 28 2025 - Warm and dry through the work week Tranquil conditions across Iowa today with high pressure allowing for light wind and clear skies. With dry conditions in place deep mixing has allowed temperatures to warm into the low to mid 80s so far this afternoon. High pressure will remain in place throughout the work week with highs in the 80s and lows in the upper 50s to low 60s. The large blocking pattern is largely unchanged until the upcoming weekend a when a trough may pass across the area, bringing the next chance for precipitation.
Air mass is dry enough to preclude much in the way of frost development in areas that do fall into the 30s and do not expect temperatures to fall to freezing in more than a very isolated way. Pattern Synopsis: A blocky pattern remains over the region for most of the week, with broad upper-level ridging remaining in place across most of the lower 48 states.
748 PM EDT Sun Sep 28 2025 Strong high pressure provides dry weather through much of the week.
733 PM EDT Sun Sep 28 2025 Strong Canadian high pressure builds south over the Great Lakes region through the middle of the week. The high will shift towards the Northeast region by the end of the week. Quiet weather continues as high pressure remains overhead through the forecast period. Strong Canadian high pressure will move overhead early this week leading to continued dry weather.
High pressure and deep layer subsidence will reside across the region through the TAF period, sustaining light winds and clear skies. A bit cooler through the overnight hours with post-frontal drying keeping skies clear and dewpoints in check. Configuration of the low-level anticyclonic flow field lends potential for warmer air to spill into southern Lower Michigan from the Upper Midwest Monday evening.
729 PM EDT Sun Sep 28 2025 High pressure is expected through the entire week, which will bring a prolonged period of dry weather.
Atmospheric decoupling has started with the valleys and typical good radiational cooling spots already dipping into the lower 60s. Elsewhere, readings were in the upper 60s to the lower 70s. Lows will be in the mid-upepr 50s on the ridges, but in the valleys and typical cooler spots, lows in the lower 50s are expected.
South- southwest flow increasing overhead as a strong trough of low pressure approaches.
Calm conditions are expected overnight with high pressure over the area. Kept the cooler than guidance temps overnight given the radiational cooling setup, so will see lows from the mid 50s to near 60. Low lying areas may see cooler pockets and possibly patchy fog at times, but widespread fog is not expected at this time.
606 PM CDT Sun Sep 28 2025 Updated at 605 PM CDT Sun Sep 28 2025 - Cooler weather is expected tomorrow with meager rain chances across the CFWA. (This evening through Monday) The upper level trough over AZ is expected to begin trekking east over NM with some amplification and negative tilting over southern NM. As such, lows tonight will stay in the high 50s and low 60s across the CWFA, and highs tomorrow to stay in the high 70s to low 80s, with localized mid-80s spots below the caprock. Otherwise, any breaks in the high- cloud shield, especially coupled with resultant outflow boundaries from convection in the NM plains can influence local updrafts which may turn into high-base convection, but confidence for that is currently low.
738 PM EDT Sun Sep 28 2025 High pressure will lead to dry and mild conditions through the week.
- Warm and dry through the work week Tranquil conditions across Iowa today with high pressure allowing for light wind and clear skies. With dry conditions in place deep mixing has allowed temperatures to warm into the low to mid 80s so far this afternoon. High pressure will remain in place throughout the work week with highs in the 80s and lows in the upper 50s to low 60s. The large blocking pattern is largely unchanged until the upcoming weekend a when a trough may pass across the area, bringing the next chance for precipitation.
635 PM CDT Sun Sep 28 2025 -Mostly clear and sunny skies are expected through the rest of the weekend -Dry conditions are expected over the next several days due to high pressure over the region -Temperatures are expected to be average to slightly above average over the next several days A mostly settled weather pattern is expected across the region over the next several days. As mentioned above, drier conditions are expected under high pressure with little to no rainfall likely through the upcoming week. (00Z TAFS) Upper level high pressure will continue to dominate through the period with widespread VFR conditions expected.
/Issued 113 PM CDT Sun Sep 28 2025/ /Today through Monday Afternoon/ Upper level ridging will continue to dominate the regional weather as the closed low remains overtop the Desert Southwest. A fetch of high moisture will continue to make its way east- northeast around the base of the low and apex of the ridge, spreading across North and Central Texas.
- Light snow can't be ruled out for the highest elevations through Monday though little to no impacts are expected on mountain roadways.
600 PM CDT Sun Sep 28 2025 - The warmer than normal conditions will continue through the week with only a slight cool down toward the weekend.
621 PM CDT Sun Sep 28 2025 - Temperatures will remain well above average for the work week with highs in the lower to middle 80s.
Currently, deep layer ridging remains in control of the regional weather. Skies are clear, with temperatures currently running into the low to mid 80s.
(Today) High pressure extends from the Northeast, through the OH Valley, into the Midwest, and down into the Southeast. Otherwise, today will be warm with highs in the lower 80s in NE AL and the mid to upper 80s elsewhere, which is ~5 degrees higher than normal.
A weak cold front will drop south tonight, which will bring slightly cooler temperatures to the region. Fog should be more ubiquitous tonight as model soundings show low level moisture trapped in the lowest levels of the atmosphere. Canadian high pressure will ridge across the Great Lakes region through the rest of the week, and will be slow to shift east due to the blocking influence of a couple tropical systems in the western Atlantic.
High pressure stays in place today, with nearly the same conditions as yesterday with afternoon highs in the mid 80s and mostly clear skies. High pressure dominates surface conditions, with highs in the mid 80s, lows in the upper 50s to low 60s, and staying dry.
High pressure and deep layer subsidence will reside across the region through the TAF period, sustaining light winds and clear skies. A bit cooler through the overnight hours with post-frontal drying keeping skies clear and dewpoints in check. Configuration of the low-level anticyclonic flow field lends potential for warmer air to spill into southern Lower Michigan from the Upper Midwest Monday evening. 850 mb temperatures likely climb into the upper teens (Celsius) overnight, but then retreat into the lower teens on Tuesday as the ridge axis over north-central Ontario absorbs the resident Midwest gyre, modifying inbound local trajectories to a northerly alignment. This marks the start of a mid-week cooldown with east-northeast flow through the lowest 15 kft of the column and a tendency for subsidence.
A stretch of quiet weather will continue through the week as persistent ridging remains in place overhead with 500 mb heights forecast to hang out right around 590 dam.
High pressure continues to be the story both at the sfc and aloft as we go through the work week ahead.
- Much cooler temperatures for Tuesday. Satellite imagery shows upper low over the desert southwest opening up allowing moisture to shift north across East Idaho. Southwest flow aloft continues with upper low churning off Seattle/Vancouver coast.
An upper level high centered near Illinois will be our primary influence through the short term period, keeping us dry. At the surface, high pressure will be positioned to our north while a pair of tropical systems begin a brief fujiwhara dance off the southeast coast. The low level flow between the high and the lows will provide us with trajectories generally the northeast to east, which will not permit any significant low level moisture advection. The main theme for much of the extended is strengthening upper and surface ridging into the Ohio valley and Appalachians keeping conditions dry and temperatures pleasant.
Atmospheric decoupling has started with the valleys and typical good radiational cooling spots already dipping into the lower 60s. Elsewhere, readings were in the upper 60s to the lower 70s. Lows will be in the mid-upepr 50s on the ridges, but in the valleys and typical cooler spots, lows in the lower 50s are expected. This tropical system will work to break down the ridging centered over the region, which will lead to slightly decreased heights and temperatures. Expecting to see high temperatures in the low-to-mid 80s.
The breezy easterly winds (sustained 10-15 mph with gusts of 20-25 mph) and high temperatures in the low 80s will make it feel a bit cooler than recent days.
A longwave mid-upper ridge will translate over the Midwest and Great Lakes over the course of this week bringing stable conditions and no precipitation to speak of through the work week. Lower level flow becomes better organized out of the north to northeast on the south end of a strong high pressure emerging out of central Canada. This draws a slightly cooler airmass into Michigan and will mainly result in daytime highs on Tuesday dropping to around 80 degrees for most of southeast Michigan with the exception of shoreline areas that will be in the low-mid 70s. The lower level flow out of the east to northeast will lead to advection of slightly cooler thermal profiles.
/NEW/ /Overnight through Monday Night/ A period of quiet weather will continue to start out the work week but water vapor imagery shows an upstream trough that will eventually spread into West Texas later today. This upper trough will be accompanied by fairly strong mid level forcing for ascent as it overspreads North Texas this evening.
Water vapor imagery/surface analysis early this morning shows Upper Michigan still under the influence of high pressure. Some of the lowest reports at this time include 38 degrees at Seney and 39 degrees in Ishpeming. Breezy E to NE flow behind the front will keep Tuesday in the low to mid 70s. Upper level ridging persists through much of the midweek, keeping above normal temps and little to no precip chances in the forecast until this coming weekend. VFR conditions continue as high pressure ridging persists over the region.
201 AM CDT Mon Sep 29 2025 - Breezy winds return this afternoon - Dry and warm conditions through the workweek - Small probability (10-20%) of rain in the later part of the weekend 07Z upper air analysis shows a large anticyclone centered near the Great Lakes with a large ridge over the eastern CONUS and a nearly stationary open wave trough approaching the four corners region. At the surface a weak lee side trough is located in eastern Colorado with a strong high pressure centered in southern Illinois. Today as the upper trough enters into Colorado and New Mexico more upper level Pacific moisture will stream into western Kansas through the day and we should see a thicker mid and high level cloud deck.
Increased cloud cover will keep highs a few degrees cooler in the mid 80s.
Expect dry and warmer weather this coming week, with increased southwesterly breezes. With abundant sub-tropical moisture still in place, along with the large-scale dynamics from the low, scattered to numerous showers and thunderstorms have begun to develop across northern Arizona.
101 AM CDT Mon Sep 29 2025 - The warmer than normal conditions will continue through the week with only a slight cool down toward the weekend.
The large upper ridge will dominate the pattern through the week.
Later in the week, high pressure moves into the region, bringing cool and dry conditions to the area. The upper level trough axis is forecast to shift atop our area, yielding upper level convergence for much of the day. The clouds and low-level northeasterly flow should maintain cooler temps across the area, with highs in the mid to upper 70s.
While the high temperatures will remain slightly above normal, the heat indices are not expected to be too high due to the amount of dry air in the region. The low temperatures are expected to remain about normal through the period.
- Slightly cooler temperatures on Monday behind a departing upper- level trough. - Drier conditions return late week as another upper-level ridge moves overhead. Today, the upper level ridge breaks down and moves east as the upper level low pushes into the four corners region. For Monday, The upper level low is expected to lift through the Rocky mountains and Intermountain West.
Be prepared for much of the same weather, as large synoptic ridge with the width the size of the CONUS has rooted itself aloft, of which will be reinforced by warm-core lows over the atlantic and strong AVA over the Eastern Canadian Provinces.
- High pressure at the surface and aloft will keep a dry air mass in place through midweek with no chance for rain, very warm days, and mild nights.
114 AM MDT Mon Sep 29 2025 - Hottest day of the week today, trending cooler thereafter. - Meteorological Overview: Upper level ridging ahead of a Pacific trough is beginning to shift eastward, away from the region early this morning. A leading wave ejecting out of the main troughing setting up just off the Pacific NW coastline today will result in scattered showers and thunderstorms this afternoon into tonight, mostly across Southwest Montana and along the Continental Divide. Additional rounds of showers and thunderstorms (Mainly in the late afternoon and evening) look to develop through much of the rest of the week as weak disturbances continue to eject from the Pacific NW troughing.
250 AM EDT Mon Sep 29 2025 Fair weather will continue under high pressure. A cooler period will begin tomorrow behind another dry cold front, leading to seasonable temperatures and chances for frost midweek. In central Canada there is evidence of a moisture-starved cold front, which will be steered southward through tonight. On its western flank we'll see a wind shift overnight and the anticipated cooler air mass filter in tomorrow. Humidity will remain low, especially east of the high peaks of the Adirondacks and higher terrain in central and eastern Vermont, dropping as low as the 25 to 35% range this afternoon. Tomorrow, cooler conditions with highs averaging 7 to 12 degrees lower than today will lead to humidity likely not dropping as low as today.
(Tonight through Tuesday night) Upper level ridging continues over the region through today, which with the higher heights we can expect another well above average day in terms of temperatures. The strong surface heating will, however, keep dewpoint temperatures in the lower 60s through mixing, helping it be a bit more comfortable outside. Going into tonight and into Tuesday the upper level flow regime starts to really breakdown and become rather stagnant as ridging develops over the Great Lakes.
230 AM EDT Mon Sep 29 2025 High pressure will produce a prolonged period of dry weather across the area through the entire week.
207 AM EDT Mon Sep 29 2025 High pressure will guarantee fair dry weather through the entire week and this weekend. A dry cold front will bring a more seasonable airmass around midweek with some risk for nocturnal frost at the higher elevations. A moisture starved cold front drops through the region Tuesday, with a cooler airmass advecting into the region.
Local sensible weather conditions remain wholly quiet with the influence of high pressure dominating still dominating the larger area. The surface and mid-upper ridge axis has shifted just E/NE of the area, with WV imagery too showing the extremely dry airmass of late having shifting eastward some.
The upper low over the Desert Southwest has finally opened up into a negatively tilted trough and will gradually track east over the Central and High Plains through today. As the trough approaches the region, height and thickness falls as well as mostly cloudy skies will cool temperatures even more compared to yesterday.
(Today through Tuesday) High pressure will remain in control of the short term.
1251 AM EDT Mon Sep 29 2025 High pressure will lead to dry and mild conditions through the week. High pressure over the Great Lakes and Ohio Valley weakens slightly today as pressures decrease to the southeast. Tonight, a stronger high pressure descending through southeast Canada begins to compress the pressure gradient over the Ohio Valley. Expect a noticeable northeast wind Tuesday afternoon as the strong high pressure to north continues to move closer to the region. This northeast wind will bring in air originating from a cooler region, allowing for subtle drop in the afternoon high temperatures, however, it will still be very warm.
High pressure has helped keep drier air in place and the shower activity mentioned earlier in the day remained confined to the higher terrain areas to our east. Overnight lows will be a few degrees warmer tonight, falling to the low to mid 60s. We will maintain a dry forecast on Monday as high pressure continues to be the dominating factor here locally while Tropical Storm Imelda continues to draw closer to the Carolinas.
- Another passing trough on Tuesday will bring more showers and thunderstorms to the elevations of western Colorado and eastern Utah.
202 AM EDT Mon Sep 29 2025 High pressure will produce a prolonged period of dry weather across the area through the entire week.
100 AM EDT Mon Sep 29 2025 High pressure to the north will combine with the tropical low pressure east of Florida to bring extensive cloudiness and eventually periods of rain to the region in the deep easterly flow through late Tuesday or Tuesday night. Stronger high pressure and some drier air will build in from the north mid-week as TD9 pulls east and well out to sea. Temperatures were noticeably cooler with readings in the mid 70s to near 80 SE. The old mid/upper low over the region will continue to shear out as ridging from the Atlantic builds westward. This will force the high moisture levels offshore back inland later tonight. Highs only in the lower 70s NW and 75-80 SE.
Highs in the mid to upper 80s today are expected to drop into the low 80s and upper 70s tomorrow as high pressure gets established.
Otherwise, expect dry conditions through mid to late afternoon Monday, when a cold front will move across the region and bring some rain chances. Warm and dry conditions prevail today, but with light to breezy winds over the Cascade Gaps and eastern mountains from the low-level upslope flow through this evening. Otherwise, the lower elevations will have 0.
High pressure will still be in control of South Central TX, but a surge of higher and some mid level cloudiness will spread into the region before lifting north of the area Tuesday.
- Cooler, more seasonable conditions, and 20 to 30 percent rain chances return at the end of the week.
Persistent ridging aloft lingers over the Midwest and MS Valley. Temperatures will continue to settle into the mid/upper 50s early this morning, with warmer spots near 60 F. Mid and upper level ridging will still be anchored over the Midwest and MS Valley on Tuesday. The ridge aloft then slowly builds east across the eastern CONUS during mid to late week. Highs in the low to mid 80s will be common, with morning lows in the low to mid 50s. The weekend also looks beautiful with high pressure lingering near the East Coast. A cold front may push southeast through portions of the Plains and Upper Midwest, but will not approach the forecast area. High pressure is positioned north of the region through the day, and NE winds are forecast to increase to around 10 kt during peak heating/mixing.
1215 AM CDT Mon Sep 29 2025 - Temperatures will remain well above average for the work week with highs in the lower to middle 80s. Low pressure was located over the Gulf of Alaska, as well as a weaker low over eastern portions of Hudson Bay. Southerly winds extended east of the trough across western and north central Nebraska this afternoon. Will trend these temperatures more toward the cooler MET/MAV numbers as they have been closer to actual lows the last couple of nights. With good mixing and H85 temps in the low 20sC, highs in the lower to middle 80s are probable Monday afternoon.