Aikyam-Lab/Synoptic-Bench huggingface dataset:
Tonight: Should see any lingering convection/rainfall quickly diminish throughout the overnight period, as lows fall into the lower 70s inland to the upper 70s along the coast. Tuesday, the forecast area will remain between high pressure over the western Atlantic a broad low pressure over the lower Mississippi River Valley.
- Relatively cooler-than-average daytime temperatures will prevail thanks to increased cloud cover and coverage of precip. Discussion: Southeasterly flow rounding the Bermuda High -- along with a weak disturbance/inverted trough over the Florida Panhandle -- is advecting tropical moisture across north and central Georgia, with PWATs generally ranging from 2. The higher terrain/mountains of north Georgia may especially be favored for efficient rainfall-producing storms thanks to southerly flow lifting over the topography.
300 PM EDT Mon Aug 11 2025 High pressure will continue to influence the region into Tuesday.
1239 PM CDT Mon Aug 11 2025 An inverted low- to mid-level trough is located over the eastern Gulf this morning.
From synopsis, an Atlantic Ridge will continue to build westward and across the Keys. The ridge will buckle briefly mid week, allowing for breezes to slacken temporarily. As the ridge continues to nose in this morning, we will see a brief surge in winds that are expected to come down this afternoon. Additional isolated to scattered showers will be possible as the ridge noses in.
The Extreme Heat Warning for the Mojave Desert will remain in effect until 5 AM tomorrow morning, with an 80 percent chance for highs of 110 or higher at Ridgecrest and a 15 to 25 percent chance in the rest of the desert region. A large high pressure ridge is currently centered off the west coast, which is leading to increased 500mb heights over California. The reason we may see a slight decrease in highs (of a couple degrees), is due to the ridge being split by a weak disturbance over the Oregon coast. This will then lead to the ridge being pushed to the east as a trough moves in from the west.
This will result in a greater chance for showers and storms as compared to previous days, although largely confined to the higher elevations, and capped at slight chance to low end chance. Temperatures will continue to tick upwards slightly Tuesday with upper ridge building overhead, with many lowland locations rebounding into the lower 90s for daytime high temperatures. Heat indices on Tuesday should top out in the upper 90s across much of the lowlands, but overall should generally stay mostly below criteria, particularly with cloud cover and convection helping to damper temperatures somewhat.
The main driver for the more active weather will be an inverted trough/easterly wave over Florida that will quickly track west across the northern Gulf.
- Daily chances for isolated to scattered showers and storms continues throughout the forecast period with the highest chances generally along and south of I-10. With general troffiness/weakness in place aloft (sandwiched between ridging to our west & east) for the next several days, we should have continued chances for some diurnally driven shra/tstms each day thru the remainder of the work week. Ridge to our east strengthens and gradually expands into the region this weekend.
141 PM EDT Mon Aug 11 2025 - Warm and muggy conditions continue today through Tuesday with highs in the low 90s and heating indices in the mid-90s. - High pressure brings less humid conditions for the latter half of the week. Relatively deep moisture between 850-500mb will wash back into Southeast Michigan this afternoon as a mid-upper level ridge structure builds from northern Ohio to Quebec. Governing high amplitude ridging maintains control through at least the first half of the daylight period today, with deeper layer stability held under a warm mid level profile lacking in meaningful thermal/moisture advection.
Highest PoPs will remain across eastern and southeastern portions of the forecast area, where highs today will top out in the low to mid 80s.
130 PM EDT Mon Aug 11 2025 High pressure remains in place today and tomorrow with temperatures remaining warm.
Better chances for showers and thunderstorms look to potentially return by the middle to end of this week, along with cooler temperatures. High pressure currently sits over California. The ridge begins to shift east over Arizona while declining in magnitude tomorrow. The ridge continues to push eastward, opening a window to allow moisture to return. This is complicated by the fact that another trough will manifest over California and potentially disrupt the flow of subtropical moisture. The trough is acting as a major point of uncertainty in ensemble guidance, and model spread is high on PW and especially surface Td.
Water vapor imagery highlights a series of upper level lows across the northern Atlantic, a TUTT cell progressing west through the Western Caribbean, and a low pressure system over the northern Gulf south of Mobile. And yet, mean layer ridging remains intact across the tropical Atlantic. An Atlantic ridge will build westward across the Florida Keys and result in gentle to moderate east to southeast breezes over the next couple of days. The ridge will buckle briefly mid week, allowing for breezes to slacken temporarily.
722 PM EDT Mon Aug 11 2025 High pressure will continue to influence the region into Tuesday.
627 PM CDT Mon Aug 11 2025 - Daily chances for showers and thunderstorms will continue through midweek with the highest chances on Tuesday afternoon (40-60%) as a cold front slowly works through the area.
An upper ridge strengthens further on Tuesday, allowing for dry conditions and even warmer temperatures as highs reach or exceed 100F in the lower valleys. A Heat Advisory is in effect for the Lower Treasure Valley and Malheur County Tuesday afternoon and evening.
Early this evening: We seem to be starting to feel the impact of the ridge aloft nosing in from the east as the coverage of showers and isolated thunderstorms has diminished significantly across the coastal waters and along the coast. Tuesday, the forecast area will remain between high pressure over the western Atlantic a broad low pressure over the lower Mississippi River Valley.
729 PM EDT Mon Aug 11 2025 High pressure remains in control through Tuesday with temperatures remaining very warm.
- Pattern change Tuesday, with cooler weather and coastal drizzle returning to the forecast. Tonight and Tuesday: The ridge that brought interior heat is finally easing tonight and Tuesday. An upstream trough will begin to nose its way into CA.
607 PM CDT Mon Aug 11 2025 Updated at 602 PM CDT Mon Aug 11 2025 - Cooler temperatures and increased storm chances (20-50%) continue through Tuesday.
826 PM EDT Mon Aug 11 2025 High pressure remains in control through Tuesday with temperatures remaining very warm.
1037 PM EDT Mon Aug 11 2025 High pressure remains centered just offshore in the Western Atlantic early this week.
718 PM EDT Mon Aug 11 2025 High pressure remains centered just offshore in the Western Atlantic early this week.
629 PM CDT Mon Aug 11 2025 Convergence along seabreeze boundaries, diurnal instability and weak forcing over deep south Texas are likely to continue to generate a near daily low (20-30%) chance of brief isolated showers and thunderstorms along and east of I-69 C as the region continues to be wedged between a mid-level high pressure over the Desert Southwest and another over the southern and southeastern US.
609 PM CDT Mon Aug 11 2025 - Daily chances for isolated to scattered showers and storms continues throughout the forecast period with the highest chances generally along and south of I-10. With general troffiness/weakness in place aloft (sandwiched between ridging to our west & east) for the next several days, we should have continued chances for some diurnally driven shra/tstms each day thru the remainder of the work week. Ridge to our east strengthens and gradually expands into the region this weekend.
Models continue to hint at an inverted trough tracking into the region from the south this weekend leading to slightly higher rain and storm chances thanks to the presence of that deep tropical moisture (PWATs around 2.
The end result is another tranquil night across the Tennessee Valley, with low temperatures trending a just a tad warmer than last night (low to mid 70s). An area of low pressure over the Gulf and the moist environment will allow for medium chances (40-60%) of diurnally driven showers and storms during the afternoon and evening.
The best opportunity for showers and storms (50-70%) will arrive mid afternoon Tuesday into Tuesday evening as the upstream frontal zone finally gets a push east in response to an upper trough releasing east through the Upper Midwest and Great Lakes. Cold front may get hung up near the US 24 corridor on Wednesday with lingering humidity and low chances (20-30%) for renewed convection if the boundary layer sufficiently recovers.
Ridging has continued to move east to southeast and this allowed for some convection to develop over the northwest periphery of the ridge into Berrien County earlier this morning. A break in the activity over the next 5-7 hours before the cold front associated with a trough pushing into the Great Lakes region today. Highs today in the upper 80s to even a few locations in the low 90s. Dew points will be in the low to mid 70s. Drier and a bit cooler airmass will usher into the area in the wake of the frontal passage and on Wednesday highs will only be in the low to mid 80s and humidity levels and cloud cover will begin to decrease through the day.
The ridge of high pressure currently parked over northern CA- western NV will expand eastward across the Great Basin today.
The upper level trough is progged to remain over the region on Tuesday, with the frontal boundary remaining stationary in our vicinity before pushing southeast into our area by the evening. With increased cloud cover, temperatures will be similar to today, ranging in the mid to upper 80s, and reaching the low 90s over portions of south-central MO. By Wednesday, the trough will begin pushing east of the area, but not before bringing additional 20-40% chances of showers and thunderstorms Wednesday afternoon.
- Upper-level ridging could bring a return of hot temperatures in the upper 90s late in the work week. An inverted upper-trough across the north-central gulf coast and a broad upper-trough across east Texas and Oklahoma will maintain increased instability across the ArkLaTex on Tuesday. However, without ample reason to assume that dewpoint values on Tuesday will differ from today, went ahead and lowered dewpoint values to the lower 70s across the region for Tuesday. The ArkLaTex will remain in a nearly stagnant pattern through the remainder of the workweek as the upper-level trough across Texas and Oklahoma remains nearly stationary.
With some lingering cloud cover through the night, lows will only drop into the low and middle 70s.
Through the week, the upper level ridges over the Southeast and Southwest will likely strengthen and shift towards Texas.
Hot weather continues through Tuesday under strong high pressure, with valley highs near or above 100 degrees in some locations. Cooler air arrives Wednesday as onshore flow strengthens and winds shift west northwesterly, bringing more seasonal temperatures through late week.
353 AM EDT Tue Aug 12 2025 - Showers and Storms Likely Today, A Few Severe Storms Possible - Cooler and Dry Late Week - Hot This Weekend With Showers/Storms Possible - Showers and Storms Likely Today, A Few Severe Storms Possible A line of thunderstorms rolling through northern Illinois early this morning may be arriving in West Michigan as early as 9 AM. - Cooler and Dry Late Week Mid-level troughing persists over the area for Wednesday keeping 850mb temps in the mid teens Celsius.
Upper level ridging that has been over the region for the past few days breaks down today as an upper level trough approaches from the west. Deep southwesterly flow east of the trough axis increases moisture by this afternoon. Upper level troughing could support enough large scale ascent in the moist environment for some showers/storms to linger overnight. On Wednesday, a weak cold front will drop into the Ohio Valley from the northwest.
222 AM EDT Tue Aug 12 2025 - Scattered Showers and Storms Today and Tonight - Showers and Storms Likely Tuesday With A Few Severe Storms Possible - Cooler and Dry Late Week - Hot This Weekend With Showers/Storms Possible - Scattered Showers and Storms Today and Tonight Scattered showers and storms are already developing across parts of West Michigan this afternoon due to a low-level convergence axis. A second round of showers and storms is expected across much of the area overnight into Tuesday morning as an MCV currently across northeast Kansas acts in concert with the low-level jet.
(Tuesday night through Wednesday night) The surface through that brought us showers and thunderstorms for the start of the week will have moved further inland to our northwest and a subtropical ridge of high pressure will begin to extend westward from the Atlantic. The high pressure will allow for temperatures to being to increase to the low-mid 90s.
- Drier and warmer for the remainder of the week. Some isolated showers and thunderstorms were forming on the back side of the low along I-70. The low will slowly swing through eastern Kansas today. The upper-level ascent with the low pressure center may combine with diurnal heating and instability to lead to more scattered storms later today, generally along and south of I-70. This will lead to a warmer and more dry (no rain but still humid) pattern through the rest of the week.
Temperatures will still remain in the low 90s, but with precipitation & cloud cover expected in the afternoon, they could decrease a couple degrees (with conditions being more humid if so).
332 AM EDT Tue Aug 12 2025 High pressure will slide out to sea today.
After today, storms will become increasingly confined to the higher terrain across far eastern Oklahoma and northwest Arkansas during the afternoon hours. During the day today, weak upper level troughing will remain overhead.
1205 AM CDT Tue Aug 12 2025 - Daily chances for showers and thunderstorms will continue through midweek with the highest chances on Tuesday afternoon (40-60%) as a cold front slowly works through the area.
311 AM CDT Tue Aug 12 2025 - "Cold" front still on track to move through the area from the northwest late today, leaving us with high pressure and a drier influx of dewpoints. But there will be plenty of convective debris clouds to erode today and may limit instability-diurnal heating some to support more of sctrd coverage as the main upstream upper trof axis will still be off to the west. The eroding debris/clouds and weak LLVL flow should keep the high temps mainly in the low to mid 80 degree range, and sfc DPTs in the low to mid 70s to last until the main upstream(real cool front) starts to sweep in this evening as the upper trof axis starts to migrate off to the east as well.
Afternoon high temperatures in the low 90s will become more common place. This will be accompanied by tall and skinny CAPE profiles with MUCAPE around 700-1300J/kg and freezing levels near 14. There has been some shift in the highest 6hr QPF amounts being more focused through the overnight hours(6-12z Wednesday), which would mean instability will be waning and could also impact rain rates to a certain extent. Not too significant of a heatwave, but high temperatures in the low 90s will become more widespread. Chattanooga Airport, TN 83 72 87 73 / 90 50 70 30 Knoxville McGhee Tyson Airport, TN 86 72 86 72 / 70 60 60 40 Oak Ridge, TN 86 72 86 71 / 80 50 60 30 Tri Cities Airport, TN 85 69 83 69 / 70 70 70 40.
A weak cold front will then cross the area late tonight and Wednesday producing scattered showers and thunderstorms with very uneven coverage.
* Hot and humid this weekend with highs in the low to mid 90s. A deepening low pressure system will move from Manitoba to Ontario today. This primary northern stream upper trough will swing east over portions of the Upper Midwest and Great Lakes today into tonight. A subtle increase in S to SW flow is noted in the lower to mid-levels, which will continue to draw deeper moisture northward into the Lower Ohio Valley today. However, at least widely scattered thunderstorms are likely due to slightly weaker ridging aloft and rich moisture in place. At the surface, a cold front will sink southeast through portions of MO, IL, IN, and MI. Lows in the low 70s will be common. Wednesday will feature warm, humid conditions with a cold front stalling over the Ohio Valley.
255 AM EDT Tue Aug 12 2025 High pressure will continue to shift to our east today.
After initially fading with sunset, showers and thunderstorms become possible again late tonight, as a mid/upper-level short wave trough over the central/southern plains early this morning approaches. Temperatures top out in the lower to mid 90s across much of the lowlands beneath the mid/upper-level ridging overhead today, but after a slight adjustment of afternoon central guidance dew points down toward the center of the guidance envelop, forecast maximum apparent temperature values are mainly in the mid to upper 90s, with a few locations briefly reaching the lower 100s.
1232 AM CDT Tue Aug 12 2025 - An easterly wave/inverted trough feature will continue to move west across the northern Gulf into Texas, increasing rain chances over the area. - The subtropical ridge from the east will build in at the end of the week to provide typical summertime weather.
1233 AM CDT Tue Aug 12 2025 Updated at 1229 AM CDT Tue Aug 12 2025 - Cooler temperatures and increased storm chances (20-50%) continue through Tuesday.
For the rest of today, the trough that aided in generating the thunderstorms yesterday will be off to the east of the area and high pressure will build in over the Four Corners region. Even though cloud cover will mostly go away today, temperatures should still be in the 80s as we are still on the backside of the H500 trough. High pressure begins to move east over the Rockies on Wednesday and this pattern will not be very favorable for thunderstorm chances. Some storms will likely form off of the higher terrain of New Mexico and Colorado but it looks like they will struggle to make it this far east on Wednesday afternoon.
High temperatures will jump several degrees as the high pressure continues to build in. The pattern Wednesday is dominated by high pressure over the Desert Southwest keeping any moisture to the south over New Mexico and Arizona. With the high extending up over eastern Utah and Western Colorado, temperatures will run five to eight degrees above normal under mostly clear skies. A trough digs south along the Pacific Coast through the day to start pushing the high pressure east letting a little moisture to slip in under the high for a few isolated afternoon showers and thunderstorms possible over the San Juan mountains to the south.
1108 PM MDT Mon Aug 11 2025 - Drier and warmer weather through Wednesday.
416 AM EDT Tue Aug 12 2025 * Humid with locally heavy thunderstorm downpours tonight and Wednesday * Mainly dry with above normal temperatures all weekend Patches of lower clouds have started to form over the Lower Susq and Laurels. They'll get tallest over the ridges/high ground and only drift away slightly. The advancing upper trough will really break down the ridge and drag a cold front into OH overnight. Lows tonight will be milder, especially in the Lower Susq where they should stay in the 70s. The high PWAT (1.
233 AM EDT Tue Aug 12 2025 High pressure will strengthen offshore the next few days, returning to a more typical summertime pattern over the Carolinas. High pressure offshore gradually sinks Sward through the period with midlevel ridge expanding Wward over SECONUS leading to weak, but more defined southerly flow through the column. Low level thicknesses grad build and the return to SSW flow should allow temps to warm into the low to mid 80s. with lows in the low to mid 70s.
Temperatures today will remain in the low 90s across the East Coast, but would reach the mid 90s across the southwest and interior early in the afternoon. Heat indices will reach the low 100s and will approach advisory criteria, but confidence regarding coverage and duration remains poor at this time. Ridging will become more fully established on Wednesday and moisture will remain near climatological norms, with sea breeze interactions once again driving scattered convection in the afternoon.
In addition to the damaging winds, a brief funnel cannot be ruled out given the low level lift from the MCV. Upper ridge stretches east into the central plains Wednesday onward as the northern stream jet shunts qpf amounts towards the Great Lakes region.
144 AM EDT Tue Aug 12 2025 A warming trend is expected as we head through the week and upper ridging sets up over the Southeastern US.
A cold front from northeast to west central MN will continue to the southeast this morning. The smoke will exit to the east with the cold front this morning, leading to better air quality today. Mild and drier air will push into the region today, accompanied by high pressure. A secondary cold front will drop south into northern MN tonight and stall across central MN and central WI Wednesday.
Compared to the last several nights, the low level jet is very weak with the "stronger" winds confined to areas just south of the Red River.
One last day of hot and mainly dry conditions today, before increasing monsoonal moisture and cooler temperatures set in through the end of the week.
The mid-level trough axis will translate east this morning and, along with weak surface convergence evident in a few higher-resolution models, serve as the focus for additional showers and thunderstorms this afternoon and evening. While most deterministic guidance shows the trough flattening and slowing down over our region, the trough axis makes slow, steady progress eastward and eventually exists. It also draws a weak cold front through the region through Wednesday morning, allowing for slightly-cooler and drier air to filter south.
1244 AM MDT Tue Aug 12 2025 KEY MESSAGES: - Summer like conditions through mid week - Gusty winds and low humidity on Wednesday with increased fire weather concerns - Cooler late week into the coming weekend Very warm and mostly dry conditions will prevail today under westerly flow aloft.
Getting some lower clouds and fog out there early this morning, with some dense fog at times along the higher peaks. Leaning toward the HRRR trends keeps chance pops into the early morning over the southern Blue Ridge into the NC foothills. At 5h models in general agreement in keeping ridge over the southeast U.
Will continue to monitor coverage of storms and expand the low PoPs as needed. An upper trough will approach the area on Tuesday, bringing an increase in forcing to the northwestern half of the forecast area. Meanwhile, a surge of moisture and weak forcing will rotate into the area around an upper high.
Ridging will remain to our north through Wednesday bringing us into a southeasterly flow regime.
pdf High pressure ridge axis remains across the region with a southerly steering flow and PWATs that have dropped below 2 inches. The later start to convection will allow for Max Temps to reach into the lower/middle 90s inland and around 90F at the Atlantic Beaches, which will combine with dew point temps generally in the middle 70s for peak heat indices in the 104-108F range, likely remaining below Heat Advisory criteria for one more day.
The higher rain chances will remain across the southeast half of the CWFA. With the increase of rain chances each day through the short term, expect temperatures to be held down just a bit, especially across the southeast half of the CWFA where the highest rain chances reside today.