Aikyam-Lab/Synoptic-Bench huggingface dataset:
Discussion: Subtropical jet to our south will intensify as an upper level trough digs down from the northern US and meets up with the jet. While PoPs will be high across the whole area, the highest rainfall will likely occur in a band of showers and thunderstorms from Morgan/Scott counties northeast through Wise, VA tonight. This heavier band is in response to stronger forcing thanks to divergence aloft from the stronger jet as it rounds the upper trough, and stronger isentropic lift.
244 AM MDT Sat Sep 16 2023 An upper level ridge persist across the state keeping flow aloft weak.
348 AM CDT Sat Sep 16 2023 1) Chances of thunderstorms will increase this afternoon, with a Marginal risk for strong to severe storms, lingering into the early evening hours 2) Quieter conditions expected tonight, with cool overnight lows A mostly dry start to the day this morning will become more active this afternoon as an upper-level trough slowly translates eastward over the upper Midwest. An attendant surface cold front will act as the mechanism for increasing chances of showers and thunderstorms this afternoon, if not in the late morning hours. The modest shear should keep the threat for strong to severe storms on the low end. With the high likelihood for a wetting rainfall with today's convection, as well as signals for clearing skies and lower dew point depressions should lead to at least some patchy fog tonight.
Saturday will be filled with plenty of sunshine and temperatures into the 80s thanks to high pressure over the region. High pressure will weaken Sunday as a dry cold front begins to nose its way into the region.
The highest risk could also be across our coastal counties from Volusia thru Martin. Weak high pressure remains situated north of the local waters promoting light onshore flow in the low-levels. This higher coverage of showers and storms will bring the potential for a waterspout or two. The persistent long period swell from distant Post-Tropical Cyclone Lee will continue to produce hazardous boating conditions esp near inlets during the outgoing tide.
641 AM EDT Sat Sep 16 2023 Clear/dry under high pressure most of today.
Other then updating fog there are no other updates A broad upper level trough continues to swing eastward, thus opening the door for an upper level ridge to move in from the Northern Rockies. Temperatures will remain cooler out east due to a low clouds deck hanging around. Tonight, low temperatures will increase a few degrees into the lower to upper 40s as an upper level ridge draws closer. Temperatures will begin to warm out west as the ridge axis moves closer to the Northern Plains. A low level thermal ridge across eastern Montana is forecast to warm temperatures out west into the mid to upper 80s while the remainder of the state is forecast to sit in the 70s.
Radar has detected scattered showers east of the trough axis during the overnight hours, but no lightning. The trough axis will remain over west Alabama through the morning hours, but then get absorbed by a cool front this afternoon. The cool front is associated with a short wave trof digging southward from the Ohio Valley states. The front and short wave trof will increase lift near the remnants of the inverted surface trof, with likely rain chances today for areas along and east of I-65. A cooler easterly flow over east Alabama will keep highs in the upper 70s to lower 80s.
Split upper trough pushing across the GLAKS and Ohio Valley will bring thickening clouds from southwest to northeast through dawn Sunday, and a few sprinkles could develop near the Maryland border by 12z Sunday over the Laurel Highlands. Some thunder possible over the Lower Susq.
443 AM MDT Sat Sep 16 2023 High pressure slowly approaches the West Slope this morning. Drier air is filtering in from the northwest in front of a building ridge of high pressure situated over the Great Basin. Temperatures are expected to rebound today as the ridge builds overhead. Sunday will see the ridge axis overhead much of the day, with temperatures bumping up a degree or two and plenty of sunshine. The medium range period begins with a flat ridge over the forecast area, a closed low off the northern California coast and another deeper closed low just off the northern coast of British Columbia.
Temperatures should top out mainly in the lower 90s both days, though convection Saturday could keep some locations in the 80s.
An upper trough was expected to move through the area later day. Areas in the west will likely get to 90, maybe the lower 90s before clouds fill in. Models suggest clouds will move in with the upper trough tonight, so overnight lows could be a few degrees warmer than anticipated. Not anticipating much rain, models show things dissipating in the evening and drier air/slightly cooler air moving in overnight. Hi-res guidance highlights a well-defined trough axis slowly moving eastward across the southeastern US region.
646 AM EDT Sat Sep 16 2023 High pressure over the region will result in quiet conditions for most of the region.
612 AM MDT Sat Sep 16 2023 Patchy river fog developing across the eastern zones this morning with temperatures dropping into the low 40s and 30s. Otherwise dry and warmer weather is expected over the next few days as upper ridge continues to build across the Rockies. Elevated fire conditions are expected again with the gusty winds, although temperatures may be slightly cooler and relative humidity slightly higher.
Otherwise, expect highs in the lower 70s today, lows in the 50s overnight tonight, and highs in the upper 60s to near 70 degrees on Sunday.
534 AM MDT Sat Sep 16 2023 An upper level ridge persist across the state keeping flow aloft weak. Sunday is shaping up to be another sunny day, and temperatures will continue their warming trend with further warm advection under a flattening ridge. We should see mid 80s across the plains for highs, with 60s to mid 70s in the high country.
Upstream, a sharp east to west oriented upper level short wave trough was moving southeast into the Panhandle. Given the lower heights, cloud cover, and rain chances high temperatures today will be slightly cooler, from the mid 80s to around 90. A drier airmass filters into the region from the north on tonight and Sunday, with ridging to the west moving closer to the area. High temperatures on Sunday will be slightly warmer, lower 90s for most areas, and upper 80s across the Hill Country.
The low is forecast to remain nearly stationary today and tonight due to opposing directional winds encompassing both sides of the low; northeast polar jet stream winds developing to the north, southwest subtropical jet stream winds to the south. A lower level cool frontal boundary associated with the low over the outer CA waters will advance eastward ushering in a net cooling across our forecast area today (and through the weekend) and this will further deepen the marine layer, usher inland more night & morning stratus with patchy drizzle forming due to onshore winds & upslope cooling along the coast. Daytime highs today 60s at the coast, a mix of mid to upper 60s and 70s bayside, to the lower to mid 80s farther inland.
Tomorrow we will be looking at lower RH across the area, possibly upper 20s at the lowest to low 30s.
Bifurcation of a positively tilted longwave trough extending from Ontario through The Plains is evident this morning in GOES vapor imagery with cyclonic circulations delineated over South Dakota and central Ontario. Expect top-down saturation processes to expand locally as the day progresses while ridging below 700 mb is slower to wane/shear-out given the upstream wave interactions with Hurricane (soon to be Tropical Storm) Lee over New England and the Canadian Maritimes. Steady moistening and cooling of the column ensures overcast skies with lowering ceilings while an attendant cold front approaches from the northwest.
Today and Sunday High pressure continues its reign over eastern Idaho through the weekend. Seasonably cool mornings will give way to afternoon highs in the lower 80s in the valleys each day.
Sunday looks to be mostly dry as the trough and surface boundary continues to gradually drift downstream away from our landbased zones taking with it the best rain/storm chances.
A broad and flat mean-layer ridge stretches across Mexico, the Gulf of Mexico, and the western North Atlantic. Water vapor imagery highlights wavy westerlies across the CONUS, with Post- Tropical Cyclone Lee nearing Nova Scotia. The low-level gradient across the Keys is very weak, with shower and storm motion very slow and to the north across Florida Bay. We will issue a zone update to highlight better chances across the Upper Keys, with only slight rain/thunder chances for the Lower and Middle Keys.
617 AM CDT Sat Sep 16 2023 Upper level trough is approaching the region this morning from the northwest. Surface cold front arrives this evening. There is just enough moisture that the front and the gap between the surface front and the upper trough could generates few showers and maybe an elevated thundershower. This trough passage has trended just a little slower over the last few runs, which lead to just a little bit higher precip chances Sunday morning before the trough axis clears. The airmass behind the front is a touch drier and cooler but not dramatically different from what we saw over this past week.
613 AM CDT Sat Sep 16 2023 (Today) A few showers will continue this morning and possibly into early afternoon across northeast Oklahoma and northwest Arkansas as an upper trough moves across the area.
An upper low is present across Ontario, Canada this morning as Hurricane Lee approaches the northeast US and Nova Scotia. The first of two cold fronts has made it through the forecast area with the second working southward from eastern Minnesota through South Dakota. Daytime heating and steepening mid-level lapse rates will lead to MUCAPE values of 800-1300 J/kg per the HREF ahead of the southward advancing cold front. Large-scale ascent from a trough digging across the central CONUS along with lift along the front is expected to generate scattered convection Saturday afternoon and evening. Most likely timing would be between 4-9pm before the cold front moves southeast of the area. Northwest flow aloft and surface ridging build in for Sunday allowing for a dry and pleasant day with highs in the upper 70s to mid 80s.
527 AM CDT Sat Sep 16 2023 (Today) Persistent low topped showers in far northwest AL along the surface inverted trough will tend to increase in coverage through the morning hours.
There could still be a few lingering showers or thunderstorms across the far southern Texas Panhandle this morning ahead of the short wave trough moving southeast from northeast New Mexico. A dry day is expected on Sunday as subsidence takes over behind the departing short wave trough. Highs today are expected to be in the mid 70's to the lower 80's and highs on Sunday are expected to be in the 80's.
618 AM CDT Sat Sep 16 2023 (Today through Sunday afternoon) A complex of thunderstorms is currently developing along a cold front across eastern New Mexico and the Texas Panhandle early this morning. Cooler weather is expected behind the cold front with temperatures remaining in the 80s for the majority of locations. Afternoon thunderstorms will once again be possible but the relatively drier and more stable airmass behind the cold front keeps coverage more isolated. Clearing skies and cooler temperatures can be expected Sunday.
434 AM CDT Sat Sep 16 2023 A broad upper level trough continues to swing eastward, thus opening the door for an upper level ridge to move in from the Northern Rockies. Temperatures will remain cooler out east due to a low clouds deck hanging around. Tonight, low temperatures will increase a few degrees into the lower to upper 40s as an upper level ridge draws closer. Temperatures will begin to warm out west as the ridge axis moves closer to the Northern Plains. A low level thermal ridge across eastern Montana is forecast to warm temperatures out west into the mid to upper 80s while the remainder of the state is forecast to sit in the 70s.
For Sunday, an upper-level trough digs southeastward, with its axis passing overhead during the afternoon. In response, an associated cold front at the surface will push across the Deep South, sweeping across our local area during the late morning and afternoon hours. Lows tonight will range from the mid to upper 60s north of I-10 to the low to mid 70s along the coast.
536 AM MDT Sat Sep 16 2023 High pressure slowly approaches the West Slope this morning. Drier air is filtering in from the northwest in front of a building ridge of high pressure situated over the Great Basin. Temperatures are expected to rebound today as the ridge builds overhead. Sunday will see the ridge axis overhead much of the day, with temperatures bumping up a degree or two and plenty of sunshine. The medium range period begins with a flat ridge over the forecast area, a closed low off the northern California coast and another deeper closed low just off the northern coast of British Columbia.
Near zonal flow aloft to allow for partly to mostly cloudy skies this morning with a few showers and isolated thunderstorms possible across east Texas, north Louisiana, and southeast Oklahoma ahead of a trough that will swing east across the region today. Conditions to gradually improve late this afternoon as subsident northwest flow builds in the wake of the trough, supporting mostly clear skies from tonight through the remainder of the weekend.
Key Messages: *Warmer temperatures return to start the beginning of the week *Dry through mid-week, next precipitation chance late Wed.
624 AM EDT Sat Sep 16 2023 Dry conditions will continue through the daytime hours today as high pressure remains in control.
upper level ridging builds along the spine of the Continental Divide. continued dry and warmer. GFS/NAM 850mb temperatures rise about 4F to 7F compared to Saturday and blending with better performing temperature guidance the past 7 days supports high temperatures in the lower to middle 80s. Low temperatures are forecast to drop into the lower to middle 50s.
401 AM CDT Sat Sep 16 2023 Key Messages: *Warmer temperatures return to start the beginning of the week *Dry through mid-week, next precipitation chance late Wed.
(Today through Sunday) Current satellite loop shows clouds increasing from the SW as the Wedge of high pressure begins to retreat to the NE/E. With the high pressure wedge centered over VA/NC moving east off the eastern seaboard by this evening, the axis of moisture will push across North and Central GA today increasing precip chances through the short term.
448 AM MDT Sat Sep 16 2023 Upper low currently north of Lake Superior will continue to move east today, with ridge building across the Northern Plains.
and slightly cooler air to the state for Sun into Sun night.
1125 AM EDT Sat Sep 16 2023 Dry conditions will continue through the daytime hours today as high pressure remains in control.
357 PM EDT Sat Sep 16 2023 Broken cloud cover can be seen on visible satellite imagery across most of Upper Michigan this afternoon as a mid-level trough rotates through the region. And, current WV imagery clearly shows moisture streaming northeastward into the associated closed low situated over northern Ontario. Key Messages: -Sprinkles and some light rain showers closer to Superior with chilly northerly flow as high pressure builds in. However, some lingering showers and sprinkles are still possible through the afternoon with some kinks in the flow as the upper trough exits eastward. Sprinkles may linger closer to the Superior into the first half of the night, but CAA and dry air behind the low will help cloud cover clear out Sunday night. The limiting factor may be some patchy fog, which could keep temperatures a couple degrees warmer than expected.
Shower and thunderstorm activity is expected to diminish overnight as a cold front makes its way across the region. Behind this boundary, expect a return of dry conditions and temperatures in the low to mid 80s.
In the low-levels, a modest increase in southerly flow and moisture transport to the north of a developing surface wave across southeastern MS/southwestern AL resulted in a band of light-moderate rain and a few embedded thunderstorms earlier this morning, which will lift northeastward and out of the CWFA by around 18Z. However, over the course of the afternoon, it appears as if a secondary low will develop within the northern portion of a broader trough axis (somewhere across north-central TN/south-central KY), with increasing streamline confluence related to this feature expected to support redevelopment of showers/thunderstorms along an axis extending from northwest AL into middle TN.
Upper level ridge development was occurring in the wake of our latest cool/wet patter, and this ridge will yield quiet weather through the Short Term period tonight through Sunday Night. The lack of a leeside trough with high pressure in place will support the continuation of light winds of 10 mph or less. A weak leeside trough will eventually form across eastern Colorado late Sunday, but it will not have much impact on our sensible weather through Sunday Night. The lower troposphere will continue to modify, and we expect afternoon temperatures Sunday to respond quite well with direct insolation. Afternoon temperatures are expected to top out in the lower to mid 80s for highs.
Issued by National Weather Service St Louis MO 252 PM CDT Sat Sep 16 2023 Currently, an upper level trough is moving southeast through the Upper Midwest, dragging a cold front with it. There is the potential for isolated thunderstorms again tonight mainly in our northeastern counties along the cold front as it passes through.
That being said there still should be some upscale growth into a scattered to possibly broken line ahead of the cold front through late afternoon.
At the surface a cold front extended from east central Iowa into central Nebraska at 18Z.
Areas of rain will gradually exit to the east- southeast this morning, as an upper trough axis moves over the region.
Meanwhile, strato- cu has been pushing into north-central Wisconsin in a cold advection regime beneath an upper trough. Forecast concerns mainly revolve around thunderstorm potential this afternoon and evening along the cold front. Meanwhile, a Canadian high pressure system will build into the region from the northwest late tonight into Sunday. North winds and clouds will support cooler temps on Sunday, with highs ranging from the upper 50s to upper 60s.
Clouds continue to thicken up as a wave of low pressure rolls up into the far srn tier in the morning. The clouds/rain should keep temps down much cooler than prev fcst had it, esp in the central mtns.
1237 PM CDT Sat Sep 16 2023 (Today through Sunday afternoon) A complex of thunderstorms is currently developing along a cold front across eastern New Mexico and the Texas Panhandle early this morning. Cooler weather is expected behind the cold front with temperatures remaining in the 80s for the majority of locations. Afternoon thunderstorms will once again be possible but the relatively drier and more stable airmass behind the cold front keeps coverage more isolated. Clearing skies and cooler temperatures can be expected Sunday.
Gradual warm up through mid week then precipitation chances increase towards the end of the week A few low-top, light showers noted on radar this afternoon as an upper level trough circulates through the region. High pressure aloft and ad the surface begins to build in tomorrow afternoon. Previous model runs were bringing in light rain/sprinkles again tomorrow, but it is now starting to show that the high pressure will already be overhead. With the north/northeasterly winds, this will lead to one more cool day with temperatures topping out in the low to mid 60s.
222 PM EDT Sat Sep 16 2023 Dry conditions will continue through the daytime hours today as high pressure remains in control.
Satellite trends have shown some convective towers, fueled by meager elevated instability and a weak 850hPa trough, that have reached infrared temperatures between -10C to -25C, meaning some isolated thunderstorms could be possible, however, overall chances should be fairly limited for any one area. Thiem (Today through Sunday) Current satellite loop shows clouds increasing from the SW as the Wedge of high pressure begins to retreat to the NE/E. With the high pressure wedge centered over VA/NC moving east off the eastern seaboard by this evening, the axis of moisture will push across North and Central GA today increasing precip chances through the short term.
Surface observations depict values in the mid 50s across northeast Arkansas increasing to the low 70s in northeast Mississippi. Latest model guidance continues to slow the movement of an approaching cold front.
(This evening through Sunday) Besides patchy fog possible on Sunday morning, tranquil weather The amplified mid-level ridge axis currently extends from Wyoming to the Arizona, with a pair of strong troughs poised to move into British Columbia. Also observed on the water vapor loop is a cut off low pressure system (well off the California shore), and to its south, a subtropical jet moving ashore the Baja peninsula.
(This afternoon through Sunday Night) An inverted trough is currently pushing across Middle Tennessee and bringing quite a bit of showers through with some surprisingly high rainfall totals in a few areas.
A trailing short wave trough was still diving south across the Texas Panhandle late this morning providing some weak lift to the area. In addition, this trough will support the passage of a weak cold front and light north to northeast winds across the forecast area this afternoon.
Warmer weather to start the week with highs in the 80s to near 90.
(This afternoon through Sunday night) An upper trough extends from the Great Lakes down through the MS River Valley to N TX as a ridge extends from Mexico up across the 4 Corners Region to MT. The trough will move east Sunday and the ridge will slide over the area.
On Sunday, the upper pattern will start to shift as an upper trough and associated cool front will move through the region. Not expecting cooler weather with this front, as highs are forecast to climb into the upper 80s to lower 90s, which is near climatic normal for this time of year.
256 PM EDT Sat Sep 16 2023 A gradual warming trend will continue through the weekend as high pressure migrates across the area and off the Carolina coasts.
These would mainly impact the Mississippi coastal counties and the lower portions of St. Sunday looks to be mostly dry as the trough and surface boundary continues to gradually drift downstream away from our landbased zones taking with it the best rain/storm chances.
High pressure shifts east, with the flow turning westerly in the next 24 hours. Temperatures will be slightly warmer across central and eastern Idaho, and still averaging 5-10 degrees above average for mid September.
Above the surface, Central Alabama is under weak cyclonic curvature with an 850-700mb trough over west Alabama. These features will slowly drift eastward this afternoon as a more amplified mid-level trough begins to pass across the Midwest with the base expected to reach the Tennessee Valley tomorrow morning as a cold front moves into northwest Alabama. Models show scattered showers and a few storms continuing this evening east of I-65 due to the growing support from the mid-level trough, but most of the activity will quickly move east of the forecast area through the morning hours tomorrow as the cold front rapidly passes through. Highs will range from the low to upper 80s.
1233 PM CDT Sat Sep 16 2023 Key Messages: *Warmer temperatures return to start the beginning of the week *Dry through mid-week, next precipitation chance late Wed.
Lows will be cooler tonight behind the rainfall ranging from the middle 60s in the Hill Country to the lower 70s elsewhere. Tomorrow night should be mostly dry with temperatures once again in the lower 60s to lower 70s.