Aikyam-Lab/Synoptic-Bench huggingface dataset:
641 AM EDT Sun Sep 21 2025 High pressure in place today will keep weather conditions quiet and dry the rest of the weekend.
The first area is northeast CA-northwest NV where a weak trough passage has already produced a few showers in Lassen County. The second area is Mono-Mineral and southern Lyon counties, where lingering instability and a weak deformation zone extending from an upper low off the southern CA coast should also allow for isolated shower/t-storm activity mainly after 2 PM.
1228 PM CDT Sun Sep 21 2025 - Start week high temperatures in the lower-middle 80s will cool into the 70s by and for the back half of the week. Subtle height falls are modeled as a reflection of the primary synoptic scale cyclone that moves in over the course of the week, with a number of pieces of pva energy channeling within the dips in the flow pattern as this metamorphosis occurs with time.
Pattern Synopsis/Forecast: Trough axis upstream continues to slowly trek east this afternoon through early/midweek. Highs Monday expected to top out several degrees above normal for many -- largely in the low-mid 70s.
207 PM EDT Sun Sep 21 2025 High pressure will extend across the Middle Atlantic through Monday, then drift to near Bermuda through mid-week. After last nights cold fropa, high pressure has continued to build back into the region. Tonight, expect areas of fog and/or low stratus to develop again, with low temperatures in the upper 50s to the low-to-mid 60s.
1225 PM CDT Sun Sep 21 2025 Upper troughing moves into the area late this evening helping to spark off isolated to locally scattered showers and storms this afternoon into evening, mainly across interior portions of the forecast area. Afternoon temperatures remain well above normal today and Monday, with highs in the lower to middle 90's.
Short wave energy from an approaching upper level trof had brought these showers with scattered thunderstorms across the forecast area this morning. More showers are expected to develop and move into northern Indiana tonight as the upper low and trof lingers over the area.
Above normal temperatures will continue through early this week before a wetter and cooler pattern develops midweek and beyond.
Before storms become more numerous this afternoon, highs will top out in the low to mid 90s once again. An upper level trough axis will move across the Ohio River Valley during the day on Monday, with best upper level forcing remaining off to the north of Central Alabama. Hot and humid conditions will continue as highs reach the lower 90s by Monday afternoon.
The low level jet streak that previous discussions mentioned, is currently progged southward. - Chances for showers and storms continues through the week A large upper level low will dominate the weather pattern this week.
A cold front will move through the region today with scattered showers and isolated thunderstorms. The cold front will bring breezy conditions this afternoon with wind gusts of 20-30 mph from the west-northwest. A ridge rebuilds over the area on Monday with warm and dry conditions for the remainder of the week. Isolated showers and thunderstorms this morning, becoming scattered this afternoon ahead/along a cold front moving W to E.
140 PM EDT Sun Sep 21 2025 High pressure will be departing off to the east tonight into Monday, which will allow for dry and comfortable weather to continue.
1242 PM CDT Sun Sep 21 2025 - Warmer then average through the week with dry weather expected. Showers developing in west central MN will continue to rotate around the upper low currently centered over Mahnomen/Clearwater counties, slowly drifting east through sunset. A very perturbed flow pattern across the northern plains will eventually give way to an omega block by the end of the week with the current group of upper lows continuing their eastward drift with a PNW trough diving south through the northern rockies early in the week becoming the eastern feature in the omega block as it dips into the southeast and deepens.
123 PM EDT Sun Sep 21 2025 High pressure will extend across the Middle Atlantic through Monday, then drift to near Bermuda through mid-week. After last nights cold fropa, high pressure has continued to build back into the region. Tonight, expect areas of fog and/or low stratus to develop again, with low temperatures in the upper 50s to the low-to-mid 60s.
The highest rain chances are tonight into Monday night (60-80% chance southeast of the IL river tonight and early Mon, and in eastern/SE IL through Monday). Surface analysis a mid afternoon shows warm front lifting northward into central parts of MN/WI. Aloft a 567 decameter low was over NW and west central MN with its trof axis extending southward into eastern parts of NE/KS and OK.
1013 AM CDT Sun Sep 21 2025 - Warmer then average through the week with dry weather expected. A very perturbed flow pattern across the northern plains will eventually give way to an omega block by the end of the week with the current group of upper lows continuing their eastward drift with a PNW trough diving south through the northern rockies early in the week becoming the eastern feature in the omega block as it dips into the southeast and deepens.
227 PM MDT Sun Sep 21 2025 - Weather system brings precipitation (40-80% chance from Rosebud County west), cooler temperatures, and gusty northwest winds to the region into Monday. The chance of precipitation will increase this afternoon into Monday, beginning over the west, as a weather system and associated cold front moves through.
143 PM EDT Sun Sep 21 2025 High pressure in place today will keep weather conditions quiet and dry the rest of the weekend.
- A cooler, but seasonable day expected on Monday.
The low pressure system that we've been monitoring has been becoming more consistent on long-range models. The Euro and GFS have agreed on more of a deep and positively tilted trough moving into the Central Plains and the Mississippi River Valley by midweek. Namely, the NAM has a deeper trough, with a central pressure of around 576 dm by 00z Wed compared to the GFS's 580, that is moving slightly faster than other models.
159 PM EDT Sun Sep 21 2025 High pressure north of the region will weaken on Monday. The mid-levels will consist of a weak trough axis moving from the Plains States to the MS River Valley, causing heights over our area to gradually drop, while southwest flow prevails. At the surface, High pressure will prevail over New England, with it's periphery reaching far into the Southeast U. Offshore, troughing will prevail. Our land areas should mostly be under the influence of the High, leading to dry conditions. Lows should range from the mid 60s far inland to the lower 70s near the coast. Weak high pressure to the north will weaken as high pressure rebuilds over the western Atlantic.
From synopsis, high pressure over the Eastern Seaboard will lead to gentle northeast to east breezes this afternoon. As we head into the new work week, this high will shift farther out into the North Atlantic and slowly weaken. Mainly light breezes, occasionally light to gentle will prevail for much of the week as weak high pressure remains across the Florida Peninsula.
The greatest chances for rain/showers during the short term period will be into early Monday and again late Monday afternoon and evening (across the NW zones along a NEWD lifting warm frontal zone, SE edge of a band of 1. High pressure and slightly lower PWATs to the east will keep any rain showers to a minimum east of I-99 and south of I-80. High temps Monday will range from the mid 70s over the higher terrain of the north and west, to the upper 70s and around 80F elsewhere.
228 PM MDT Sun Sep 21 2025 - Warm again tomorrow with increasing thunder chances, then cold front passage late afternoon/evening.
A central states upper trof progresses into the eastern states through Monday and weakens, with a vigorous system meanwhile diving from the northwest states towards the central Plains.
Current surface analysis places low along the Saskatchewan/Alberta border with trough dropping down into central/eastern Montana. Upper level analysis places ridge stretching from the Four Corners region northward into eastern Montana, while a compact low spins over northern Minnesota. Over our area, quiet weather continues with a modest southerly wind ahead of the aforementioned trough. Skies are mostly clear, but some afternoon fair weather cumulus have developed over eastern parts of our area in the modest cyclonic flow on the backside of the aforementioned upper low. On Monday, trough meanders east before stalling out over central North Dakota.
100 PM EDT Sun Sep 21 2025 Warm and dry weather will continue through mid week with high pressure the dominant weather feature. Unsettled weather is likely late this week as a cold front approaches. High pressure to the northeast will keep a dry northeasterly flow in place although the axis will weaken by MOnday PM.
1115 AM MDT Sun Sep 21 2025 -Sunny and warm today -Cool front will bring breezy winds and a few showers to the area Monday -Dry with above normal temperatures mid-week on Upper ridge ahead of the Pac NW upper trough will support sunny and warm conds today. After this trough passes through the region, blocking ridge will build into the region, supporting dry and warm weather. Upper trough will dive SE into the central Rockies Monday, forcing a cold front into the region. Upper ridge will build across the Northern Plains as a quasi-omega block develops, with dry weather and above normal temps looking likely across the region. A cold front will slide through the forecast area between 22/06Z and 22/12z.
With the surface-1km wind backing some this afternoon/evening, hodographs do develop some nice turning in the low levels down between Watertown and Brookings. It's going to take a while for the axis of upper level ridging to get over the CWA, as the pattern aloft over the lower 48 states will continue to showcase a split flow/blocky pattern where large-scale ridges and trofs will be slow to move. But, eventually, a broad and semi-flat upper level ridge will establish over the northern half of the contiguous U.
Monday will bring similar weather to today as the upper low over MN moves eastward across the UP, bringing another round of showers and thunderstorms.
Cooler weather with a few lingering showers Sunday evening will will trend drier and warmer Monday.
With upper level troughing moving into our region and a deeper southerly flow, local radars continued to show a few showers and thunderstorms along the Interstate 55 corridor north if Interstate 20. Otherwise, warmer than normal temperatures will continue.
734 PM EDT Sun Sep 21 2025 High pressure north of the region will weaken on Monday. The mid-levels will consist of a weak trough axis moving from the Plains States to the MS River Valley, causing heights over our area to gradually drop, while southwest flow prevails. At the surface, High pressure will prevail over New England, with it's periphery reaching far into the Southeast U. Offshore, troughing will prevail. Our land areas should mostly be under the influence of the High, leading to dry conditions. Lows should range from the mid 60s far inland to the lower 70s near the coast. Weak high pressure to the north will weaken as high pressure rebuilds over the western Atlantic.
720 PM EDT Sun Sep 21 2025 High pressure will extend across the Middle Atlantic through Monday, then drift to near Bermuda through mid-week. After last nights cold fropa, high pressure has continued to build back into the region. Tonight, expect areas of fog and/or low stratus to develop again, with low temperatures in the upper 50s to the low-to-mid 60s.
Meanwhile, there is a minor signal of patchy fog overnight in northern portions of the TBW CWA with latest HREF probabilities of visibilities less than a half mile around 10%-20%, though an increase in mid/high level cloud cover keeps forecast confidence on the low side.
This in concert with a broad trough across Florida and the Bahamas has resulted in gentle northeast to easterly breezes across the Keys this evening. Lower level moisture, associated with the broad trough, has increased across our area. Despite the current limited activity on radar, the Keys region is transitioning to a wetter pattern as the previously mentioned trough, and attendant moisture, shifts westward further across our area. In addition, a fairly amplified upper level trough will remain aligned across the Gulf. With the westward shift of the trough, gentle northeast to easterly breezes will shift east to southeasterly. Meanwhile, broad troughing aligned across Florida and the Keys will continue to shift slowly westward. While convective activity is minimal this hour, low level moisture will be on the rise and broad troughing will remain.
717 PM EDT Sun Sep 21 2025 Above normal temperature is expected ahead of a developing upper level low, which may spawn increased shower and thunderstorm chances through Monday. Otherwise, a blanket of cloud cover and 5-10 mph southerly flow will keep low temperatures well above normal to the tune of 8-10 degrees across the board only settling into the low to mid 60s.
324 PM MDT Sun Sep 21 2025 - Isolated to widely scattered showers and storms will continue this afternoon favoring the high terrain north of I-70.
809 PM EDT Sun Sep 21 2025 Warm and dry weather will continue through mid week with high pressure the dominant weather feature. Unsettled weather is likely late this week as a cold front approaches. High pressure to the northeast will keep a dry northeasterly flow in place although the axis will weaken by MOnday PM.
548 PM MDT Sun Sep 21 2025 - Warm again tomorrow with increasing thunder chances, then cold front passage late afternoon/evening.
738 PM EDT Sun Sep 21 2025 High pressure and dry conditions start off the work week. Skies should remain mostly clear tonight allowing temperatures to fall into the lower to mid 60s by daybreak.
542 PM MDT Sun Sep 21 2025 - Isolated to widely scattered showers and storms will continue this afternoon favoring the high terrain north of I-70.
620 PM CDT Sun Sep 21 2025 A central states upper trof progresses into the eastern states through Monday and weakens, with a vigorous system meanwhile diving from the northwest states towards the central Plains.
343 PM MDT Sun Sep 21 2025 - Breezy conditions and overspreading precipitation continue into Monday as a Pacific system causes widespread rain and cooler temperatures to start the week.
A subtle jet rounding the base of this trough and an associated vorticity maxima moving over southern portions of the forecast area today and tonight will facilitate another round of showers and thunderstorms, with cloud cover already overspreading the region from south to north. The best chance for showers and isolated thunderstorms will be south and east of I-15 across portions of San Bernardino, Mohave, and southern Clark Counties, with lightning, gusty winds and locally heavy rain the primary concerns, especially for storms that develop over the higher terrain. Ensembles continue to differ on the timing and trajectory of this low as it eventually moves inland toward the latter half of the work week, though once it finally translates eastward, precipitable water values are progged to ramp up closer to 150-200% of normal.
656 PM EDT Sun Sep 21 2025 High pressure will be departing off to the east tonight into Monday, which will allow for dry and comfortable weather to continue.
829 PM EDT Sun Sep 21 2025 Warm and dry weather will continue through mid week with high pressure the dominant weather feature. Unsettled weather is likely late this week as a cold front approaches. High pressure to the northeast will keep a dry northeasterly flow in place although the axis will weaken by MOnday PM.
942 PM EDT Sun Sep 21 2025 Warm and dry weather will continue through mid week with high pressure the dominant weather feature. Unsettled weather is likely late this week as a cold front approaches. High pressure to the northeast will keep a dry northeasterly flow in place although the axis will weaken by MOnday PM.
Meanwhile, model and synoptic analyses still show high pressure lingering over the SE CONUS, but being gradually weakened by a frontal feature establishing across the SC/GA region.
555 PM MDT Sun Sep 21 2025 - Breezy conditions and overspreading precipitation continue into Monday as a Pacific system causes widespread rain and cooler temperatures to start the week.
Gusty northwest winds to 40 mph already blowing across SE Oregon this evening and they will push through the lower Snake Plain early tonight, with the strongest winds (to 35 mph) from the Snake River to the ID/NV border.
The HREF shows a warm front lifting north, roughly into the vicinity of Highway 29, with 1000-1500 J/kg of SBCAPE south of the front.
Afternoon temperatures remain well above normal today and Tuesday, with highs topping out in the lower to middle 90's.
1129 PM MDT Sun Sep 21 2025 - Warm again tomorrow with increasing thunder chances, then cold front passage late afternoon/evening. - Closed low to move over state Tuesday-ish bringing high elevation snow and cool damp weather to a good part of the remainder of the region.
This will keep decent rain chances in, with the highest potential during the Tue night into Wed morning time frame.
Temperatures along the Island Chain are in the lower 80s with dew points in the upper 70s making it still feel like we are in the droves of summer. High pressure remains over the Eastern Seaboard extending southward towards Florida. There is also a subtle inverted trough moving slowly northwestward towards the Keys early this morning. A broad upper trough across the Gulf will slowly lift to the northeast through tonight. In conjunction with this, a weak inverted trough is slowly propagating westward towards the Florida Keys early this morning. In the lower to mid levels, there is also a fair amount of moisture streaming into the area. As the upper level trough lifts northeastward, some weak ridging builds into the region.
A series of fronts and waves of low pressure will bring clouds and shower chances each day. High temperatures will be above average again today, with temperatures in the mid to upper 70s, and some areas hitting in the low 80s. Temperatures will be slightly cooler than today, but still warm and above average in the low to upper 70s. Heading into midweek, the region will be under a upper level trough with lingering moisture and instability in the NW flow regime.
Troughing aloft will continue increasing across the region overnight into Monday. However come Tuesday, flow across Lower Mississippi River Valley will become more zonal ahead of a low pressure system moving east across the central plains states. It'll be this low that brings us some much needed rainfall come mid/late this week. However, some small rain chances will linger late tonight across the Highway 82 corridor, as a disturbance aloft moves east across the Mid-South region during the overnight hours.
347 AM EDT Mon Sep 22 2025 Above normal temperature is expected ahead of a developing upper level low, which may spawn increased shower and thunderstorm chances through Monday.
However, as this low intersects the boundary; stronger convection should take off in northwestern IA and portions of the lower Missouri River Valley then gradually progresses southeastwards during the evening. From here, should see things quiet down during the overnight hours as temperatures drop into the low to upper 50s for lows. Looking into the midweek onwards, a pattern shift begins to take shape as the departing long-wave trough is replaced by building upper-level ridging.
* High pressure will shift over northern CA through Tuesday as a cut-off low pressure moves into southern CA.
251 AM EDT Mon Sep 22 2025 Above normal temperature is expected ahead of a developing upper level low, which may spawn increased shower and thunderstorm chances through Monday. Otherwise, a blanket of cloud cover and 5-10 mph southerly flow will keep low temperatures well above normal to the tune of 8-10 degrees across the board only settling into the low to mid 60s.
An upper low is moving through northern Minnesota this afternoon, as noted by the spinning nature of the clouds on satellite. Cannot rule out a thunderstorm given the forcing associated with the closed low and CAPE values of 1000J/kg or greater. Shower activity diminishes this evening across Minnesota, with low chances of showers and a storm continuing over portions of northwest Wisconsin overnight as the upper low slides eastward toward the Great Lakes. Upper level ridging extends into southern Canada, arching over the Great Lakes toward Hudson Bay mid week. High pressure remains in place through the week, keeping conditions rain free, with above normal temperatures through at least this week of September. That means highs in the low to mid 70s by the end of week, roughly 10 degrees above normal.
Conditions will trend drier and warmer for the first half of the week.
An upper-level trough and upper-level lower pressure are over MT/WY this morning and will move southeast though today and Tuesday. Models are showing the highest chances to the south of SD, with areas in southern Jones and Lyman counties being on the northernmost edge of the precipitation chances, with less than 20% chance for rain. This higher pressure helps to reduce the chances for rain and storms Tuesday. Temperatures look to be in the low to upper 70s both today and on Tuesday.
1135 PM MDT Sun Sep 21 2025 - Breezy conditions and overspreading precipitation continue into Monday as a Pacific system causes widespread rain and cooler temperatures to start the week.
During midweek a cold front will move into the eastern U. suppressing the ridge axis south across the Florida peninsula with the low level flow becoming rather light and eventually south to southwest. Enough moisture will remain across the area to see isolated to scattered mainly afternoon and evening showers and thunderstorms, with the highest PoPs over the interior and inland southwest Florida.
Through the morning, radar showed light returns streaming through southern Mohave County in response to a weak southwesterly upper level jet ahead of an upper level low off the Southern California Coast. Ensembles continue to differ on the timing and trajectory of this low as it eventually moves inland toward the latter half of the work week, though once it finally translates eastward, precipitable water values are progged to ramp up closer to 150-200% of normal.
As high pressure pushes off the US east coast, surface flow will become more easterly today and tomorrow. High temperatures will be on the cooler side due to increased cloud cover with highs topping out in the upper 80s each day.
- Warmer then average through the week with dry weather expected.
That will leave the local area in between the departing system and a upper level trough which will dig from the northern Rockies into the central Rockies. A second round of storms is expected over night tonight as the upper level trough moves from the central Rockies into the western High Plains. This will force a cold front into the area. Tuesday morning the cold front will continue to sag through the CWA continuing thunderstorm chances while late Tuesday into Tuesday night a elongated trough extending from the Great Lakes into the central Plains will continue shower and thunderstorm chances.
The cold front that brought widespread showers and isolated thunderstorms to the region yesterday has moved east of the Continental Divide this morning. Isolated rain showers have lingered overnight on the backside of the trough and will continue to move east through the morning hours. Sheltered, low-lying areas across western Montana and the higher valleys of north-central Idaho have the highest potential for seeing temperatures drop to near or below freezing. High pressure will build back over the Northern Rockies mid-week, causing high temperatures to moderate.