Aikyam-Lab/Synoptic-Bench huggingface dataset:
DISCUSSION: Upper level ridge axis is positioned nearly on Wyoming's eastern border this afternoon, contributing to hot, dry, and windy conditions. Saturday the ridge begins to flatten out and the backdoor cold front starts creeping into northeast portions of the forecast area.
517 AM EDT Fri Sep 8 2023 A cold front will slowly cross the area today bringing a few showers and thunderstorms with the greatest risk of rain to the east. Cold front entering western New York early this morning will crawl eastward today. Northerly component behind the front and plenty of low level moisture will maintain a fair amount of cloud cover which will keep high temperatures in the lower to mid 70s.
Temperatures were generally in the lower 60s across the region, though under the cloudiness, temperatures were in the mid-upper 60s. For Today, the Ohio Valley will be on the northeast periphery of the southwestern US ridge axis. Mid-level troughing over the midwest will drop southeast along the edge of the ridge axis and help carve out a larger upper level trough over the eastern US. With the upper trough moving through, a mix of sun and clouds will be seen today. Moisture profiles are fairly marginal in the low-mid levels and a few sprinkles or light rain showers can't be ruled out. Lows tonight will range from the upper 50s to the lower 60s. Subsidence associated with the high to our north will produce an inversion that will trap moisture between 700-850mb.
Upper level high pressure developing over the desert southwest will gradually shift south into northern Mexico into the weekend, as trough over the Gulf of Alaska deepens over the eastern Pacific.
655 AM EDT Fri Sep 8 2023 A cold front will slowly cross the area today bringing a few showers and thunderstorms with the greatest risk of rain to the east. Cold front entering western New York early this morning will crawl eastward today. Northerly component behind the front and plenty of low level moisture will maintain a fair amount of cloud cover which will keep high temperatures in the lower to mid 70s.
607 AM CDT Fri Sep 8 2023 (Today through Saturday afternoon) The 500mb ridge will continue to sit over the southwestern CONUS, promoting warm and mostly dry conditions across the MAF CWA.
An upper level ridge over the southern Rockies will persist today and tonight. A weak cold front with northeast winds will result in slightly cooler temperatures today, with highs in the lower 90s. Another warm day can be expected Saturday with highs in the lower 90s. Thunderstorm chances are not very good through early Saturday evening as the upper level trough and surface cold front will stay too far northwest.
648 AM EDT Fri Sep 8 2023 (Today and tonight) An upper low in the base of a longwave trough will move from south-central Georgia this morning to northeast Florida this afternoon. This corresponds roughly with the expected southern extent of a cold front this afternoon. So within the moister air mass to the south, PW values are high enough to support deep, moist convection, especially with added lift from the upper low, the cold front, and our more routine seabreeze-inspired sources of lift. Back in the drier air north of the front, the air mass will not be any cooler, but it will be drier.
Smoke trapped in the high could linger through some central and eastern areas this morning, diminishing this afternoon. Right now the higher chances for precipitation look to be along and south of Interstate 94.
The low-level gradient across the Keys remains weak, in part due to the persistent long wave trough across the eastern US. Water vapor imagery highlights a wound-up short wave diving into northern Florida, which will reinforce the equatorward extent of the long wave trough.
Even with yesterday's trough passage, the stable air mass and weakness of the trough have supported an increase in the coverage of moderate amounts of haze and smoke west of the Cascades. The smoke is being generated by the Tyee Ridge Fire in Douglas County, and also the Smith River and Happy Camp Complexes.
608 AM CDT Fri Sep 8 2023 (Today and tonight) Looks like another day of dangerous heat across much of the area with a strong upper level high over the area and an intense low level thermal ridge over the northwest part of the area.
647 AM EDT Fri Sep 8 2023 Clouds and thunderstorm chances increase into this weekend as a weakening cold front meanders over the Carolinas. Another cold front should arrive midweek. A cold front becomes nearly stationary as it stalls and meanders across the Carolinas. Deep moist southerly flow will continue between high pressure to the east and mid to upper trough which cuts off over GA this morning. Temps today will be several degrees cooler with 850 temps on a steady decline from Thurs into Sat. Deep troughing will prevail along with abundant moisture which will lead to an enhanced risk for showers/storms at times, mainly on Saturday. A cold front looks to stall over or near the area before dissipating early in the period, with another cold front moving into the area late in the period.
636 AM CDT Fri Sep 8 2023 -Slightly warmer temperatures today. Look for warmer temperatures today in the wake of this system, with highs expected to climb into the mid 70s to near 80 degrees.
Mostly clear skies will develop in its wake and provide for a slightly warmer day today. -Slightly warmer temperatures today. Look for warmer temperatures today in the wake of this system, with highs expected to climb into the mid 70s to near 80 degrees.
Temperatures are expected to be a little cooler than yesterday afternoon due to rain and additional cloud cover. Afternoon highs are forecast mostly in the low 90s.
634 AM CDT Fri Sep 8 2023 (Today through Saturday) Upper ridging centered over New Mexico this morning, with troughing from the eastern Great Lakes to Georgia. Temperatures at 3 AM CDT were generally in the lower and middle 70s. By Saturday evening, the ridge should be centered near the Arizona-New Mexico border, or perhaps a little west of there. As the mean trough to our east deepens on Saturday, it will continue to pull drier air into the area.
(Today through Saturday afternoon) The 500mb ridge will continue to sit over the southwestern CONUS, promoting warm and mostly dry conditions across the MAF CWA.
512 AM MDT Fri Sep 8 2023 07z surface analysis had lee trough from central MT into central WY. Another trough noted from eastern ND to central KS. Water vapour loop depicted upper ridge centered over southern NM with southwest flow aloft over the northern Plains. Convective initiation likely midday near trough/Black Hills, moving east into the evening hours. Saturday, much cooler air is pulled into the CWA as cold front moves through early.
Temps today will be hot once again, although should be a 2-3F cooler than yesterdays max temps. Key Messages: 1) A weak cold front arrives for Saturday, bringing chances for isolated showers and thunderstorms across portions of the area.
(Today and tonight) Looks like another day of dangerous heat across much of the area with a strong upper level high over the area and an intense low level thermal ridge over the northwest part of the area.
635 AM EDT Fri Sep 8 2023 Moist northerly flow will persist in wake of low pressure with MVFR to spotty IFR cigs this morning gradually giving way to higher MVFR to lower VFR late today into tonight. Weak troughing remains parked over the Great Lakes today but will continue to weaken with time. Light, cool north to northeast wind continues into Saturday as Canadian high pressure builds into the western Great Lakes.
654 AM EDT Fri Sep 8 2023 High pressure centered over the Great Lakes will extend into the area through the weekend.
628 AM CDT Fri Sep 8 2023 (Today and tonight) The heat underneath the long-persistent upper high will bring another day of record-breaking afternoon temperatures to southwestern Oklahoma and adjacent areas south of the Red River. South to southeast east of the low will bring very humid air into southeastern Oklahoma. These features along with a weak upper wave moving around the northeastern periphery of the upper high will bring good chances for thunderstorms over south central and southeastern Oklahoma this afternoon and tonight.
623 AM EDT Fri Sep 8 2023 A cold front moves south of the region this morning. High pressure spreads over the Great Lakes late today through Saturday night. Low pressure and associated cold front moves east across the Great Lakes region early to mid week. A cold front continues to make southward progress across the area this morning. Shower chances will tend to decrease and move south with the cold front, with no rain expected by this afternoon. An upper-level trough over Illinois area moves southeast, becoming an upper low over southern Appalachia by Saturday.
1011 AM EDT Fri Sep 8 2023 Clouds and thunderstorm chances increase into this weekend as a weakening cold front meanders over the Carolinas. Another cold front should arrive midweek. A cold front becomes nearly stationary as it stalls and meanders across the Carolinas. Deep moist southerly flow will continue between high pressure to the east and mid to upper trough which cuts off over GA this morning. Temps today will be several degrees cooler with 850 temps on a steady decline from Thurs into Sat. Deep troughing will prevail along with abundant moisture which will lead to an enhanced risk for showers/storms at times, mainly on Saturday. A cold front looks to stall over or near the area before dissipating early in the period, with another cold front moving into the area late in the period.
We're enjoying a much more comfortable air mass in wake of the front that moved through earlier in the week as dewpoints are holding in the lower 60s. Otherwise, expect a beautiful, mostly sunny day -- with highs in the low to mid 80s.
423 PM EDT Fri Sep 8 2023 High pressure will slowly build across the Great Lakes tonight through the weekend.
1255 PM EDT Fri Sep 8 2023 Light northerly winds will attempt to usher in drier air as high pressure settles over the northern Great Lakes. Weak troughing remains parked over the Great Lakes today but will continue to weaken with time. Light, cool north to northeast wind continues into Saturday as Canadian high pressure builds into the western Great Lakes.
Isolated to scattered thunderstorms this evening, mainly along the higher terrain in the Southern Appalachians. Best chances will again be over the higher terrain, including the Cumberland Plateau, but chances will increase for the Valley as opposed to today.
Cooler temperatures to start the week, with a warm up to near or above normal temperatures by the end of the week. Given the fact that thunder will be difficult to achieve, one can all but neglect the high-end QPF outliers.
On the backside of this low, wind gusts as high as 18 knots are being observed.
Dry southwesterly flow today behind yesterday's exiting upper level trough.
142 PM EDT Fri Sep 8 2023 A cold front will stall to our south and east tonight and Saturday.
(Through Saturday) The upper troughing regime with attendant cutoff low will persist through the near term.
A secondary cold front will bring a reinforcement of cool and dry air to the Mid-South this weekend with highs in the 80s with lows mostly in the 60s.
Smoke from the Tyee Ridge fires will affect areas in the Umpqua Valley at times, especially during the late afternoon and evening hour, including at Roseburg.
Southeast flow and upper divergence Saturday morning will start to bring a better chance of showers into the southern Blue Ridge/foothills during the morning with coverage expanding northwest through the day. Lows stay muggy in the 60s, with cooler highs Saturday in the 70s, except for a few lower 80s in the piedmont. Showers will linger into Sat night as the upper trough stays over the TN valley.
146 PM EDT Fri Sep 8 2023 High pressure centered over the Great Lakes will extend into the area through the weekend.
115 PM EDT Fri Sep 8 2023 (Rest of today through Saturday) Models depict a mid-level trough moving over the SE CONUS and the northern portions of the Florida peninsula. By Saturday, guidance show the aforementioned trough/low complex lifting further northeast and into the western Atlantic, dragging with it some of the moisture and best dynamic support.
Locations near bodies of water will have the highest chance for seeing minor impacts due to the fog.
256 PM CDT Fri Sep 8 2023 Currently have upper ridging situated over the Desert Southwest and spans across all of the southern Plains. At the surface, high pressure is located over the Western Great Lakes region with a stationary front down across southern OK/Northern TX. Not much is expected to change for tonight into Sat with the upper ridging remaining strong across the Desert Southwest with upper troughing over the Ohio/Tennessee Valleys. This will continue to promote above normal temps for Sat with highs generally in the low 90s. For Sat night into Sun, upper energy will move out of southern Alberta/Saskatchewan and into the Northern Rockies which will allow a strong cold front to be on the move.
(Rest of today through Saturday) Models depict a mid-level trough moving over the SE CONUS and the northern portions of the Florida peninsula. By Saturday, guidance show the aforementioned trough/low complex lifting further northeast and into the western Atlantic, dragging with it some of the moisture and best dynamic support.
The current forecast has the highest POPs across far western areas, but with the focus possibly being a bit farther west, am generally only carrying chance POPs at best. Highs are expected to rise into the low to mid 90s, but with dewpoints in the 60s (or even 50s for northern areas) the relative humidity will be low enough that it doesn't feel oppressive.
1251 PM CDT Fri Sep 8 2023 (Today through Saturday) Upper ridging centered over New Mexico this morning, with troughing from the eastern Great Lakes to Georgia. Temperatures at 3 AM CDT were generally in the lower and middle 70s. By Saturday evening, the ridge should be centered near the Arizona-New Mexico border, or perhaps a little west of there. As the mean trough to our east deepens on Saturday, it will continue to pull drier air into the area.
Sunny skies will be around most of the day Saturday, only giving way to incoming clouds in the late evening ahead of an incoming cold front that will bring precipitation to the area late on Saturday.
329 PM EDT Fri Sep 8 2023 An upper short wave now located over the MO/IL border will undergo amplification as it pushes south across the Lower Ohio and Tennessee Valleys tonight into Saturday. Meanwhile, gradual deepening of the northern stream trough across the plains will drive a slow moving low to mid level ridge across Lower Mi during the course of the weekend.
There's also the possibility of radiation fog/lower stratus forming over nrn sections later tonight where clear skies and light winds prevail closer to the ridge axis. So despite the arrival of surface ridging, low clouds may continue to plague the area to some extent into Saturday morning before more substantial clearing develops in the afternoon. Forecast soundings/low level RH overviews suggest the risk of radiation fog/stratus under the ridge axis again on Saturday night.
1218 PM CDT Fri Sep 8 2023 The bi-state region currently sits in an area of northwest flow aloft, situated between an upper level ridge centered in southern NM/west TX and a trough extending from eastern Canada south through Appalachia. At the surface, high pressure centered in the Upper Midwest stretches south into the Mid-Mississippi Valley. This will create a light east-west temperature gradient across the region, with central Missouri peaking in the low 80s and south central Illinois peaking in the mid to upper 70s this afternoon.
1107 AM EDT Fri Sep 8 2023 A cold front will finish crossing our region this afternoon. A very slow moving cold front has pressed through the bulk of the forecast area.
1214 PM CDT Fri Sep 8 2023 18z Aviation Update for TAF Issuance Dry weather and below normal temperatures are expected to continue through the short term forecast period as high pressure remains in the Great Lakes region. Areas of low pressure are located in Oklahoma and in Southern Quebec. Daytime winds around 7-10 mph out of the NNE are expected Friday and Saturday while we are positioned southeast of the high pressure center. An upper trough moves through Saturday, but models don't produce enough moisture or instability to result in precipitation, leaving only an increase in cloud cover.
404 PM EDT Fri Sep 8 2023 A slow moving cold front moves into the area tonight.
The actual ridge more or less parallels the Mississippi River Valley, so our winds are still out of the north. While high pressure will continue to dominate our surface pattern, an upper trough will come down the northwest flow aloft and developed a closed low by tomorrow evening.
High pressure will push temperatures back to several degrees above average, with record to near record heat expected this weekend. Warm air aloft, warm mid-levels with additional warming expected throughout the day as the 500 mb high center slowly moves into the area from the east, and a massive inverted V in the lower levels.
With moisture depth being limited in the lower atmosphere, think any additional shower chances will be pretty slim. Could see an isolated shower or sprinkle in our eastern zones where moisture depth in the low-levels are slightly higher vs out west.
1216 PM CDT Fri Sep 8 2023 (Today and tonight) Looks like another day of dangerous heat across much of the area with a strong upper level high over the area and an intense low level thermal ridge over the northwest part of the area.
MDT Fri Sep 8 2023 KEY MESSAGES: 1) Near critical fire weather conditions will continue this afternoon and evening in the higher elevation basins of southeast Wyoming.
243 PM EDT Fri Sep 8 2023 Unsettled weather will continue through the weekend as disturbances rotate across the region, associated with a slow- moving upper trough.
1116 AM MDT Fri Sep 8 2023 07z surface analysis had lee trough from central MT into central WY. Another trough noted from eastern ND to central KS. Water vapour loop depicted upper ridge centered over southern NM with southwest flow aloft over the northern Plains. Convective initiation likely midday near trough/Black Hills, moving east into the evening hours. Saturday, much cooler air is pulled into the CWA as cold front moves through early.
The upper level high and 850 thermal ridge will start to shift further west after today. They will still impact our temperatures over the weekend, bringing hotter than normal and potentially record breaking temperatures, but the highs should drop a few degrees from today to tomorrow. A cold front will be to our northwest, progressing towards our area, which could fire up a few storms. The cold front mentioned above, is expected to progress further south tomorrow and stall over our area.
However, with inconsistencies in guidance and further west solution, will lean on the lower end of PoPs for the far western areas.
159 PM EDT Fri Sep 8 2023 Upper air pattern consists of a 500 mb ridge over the Rockies and a trough across the eastern U. with a trough across south central Canada. Troughing moves into the northern plains 12z Sat.
A drier air-mass will begin to filter into the region on Saturday as weak high pressure builds over the area with light northeast winds. Highs will remain slightly above normal with temperatures in the lower 90s across most of eastern Oklahoma/west-central Arkansas.
The upper level low that sat at the Canadian coast all week is finally lifting to the east. The movement of this low eastward is allowing the upper level ridge over the Desert SW to build northward, and the protection of the ridge will prevent thunderstorm activity and precipitation in the Snake River plain and south central highlands through the weekend and into Mon. Mon is a transition day as a new upper level low moves into the Canadian coast. Showers and thunderstorms are possible in northern areas late this afternoon and tonight as low pressure moves through southern Canada. Fortunately, afternoon wind, while gusty, should not get significantly strong under the high that builds in behind the Canadian low.
1200 PM CDT Fri Sep 8 2023 (Today through Saturday afternoon) The 500mb ridge will continue to sit over the southwestern CONUS, promoting warm and mostly dry conditions across the MAF CWA.
147 PM EDT Fri Sep 8 2023 Clouds and thunderstorm chances increase into this weekend as a weakening cold front meanders over the Carolinas. Another cold front should arrive midweek. A cold front becomes nearly stationary as it stalls and meanders across the Carolinas. Deep moist southerly flow will continue between high pressure to the east and mid to upper trough which cuts off over GA this morning. Temps today will be several degrees cooler with 850 temps on a steady decline from Thurs into Sat. Deep troughing will prevail along with abundant moisture which will lead to an enhanced risk for showers/storms at times, mainly on Saturday. A cold front looks to stall over or near the area before dissipating early in the period, with another cold front moving into the area late in the period.
Light winds this morning, with high relatively humidity, so wouldn't be surprised if fog starts to get a little more observant while we sit under this low level COL. We are under a weak thermal ridge with 850mb temperatures between +15 and +18C, so should mix out into the 80s with ample sunshine. The gradient on the backside will support breezy conditions, and we will also see cooler air back in behind the low. Convection should be elevated given timing, with a warm front in south central South Dakota around midnight. To start the period strong upper high pressure over the southwest CONUS will get somewhat cutoff from ridging over western Canada.
With ridging aloft beginning to build westward over the Desert Southwest into the weekend, the forecast area looks to remain firmly underneath west-southwesterly flow aloft. Otherwise, given the orientation of the ridging aloft, as well as the projected path of current Hurricane Jova, a lobe of midlevel moisture is expected to advect inland across portions of central California on Saturday.
Scattered showers and storms will be possible Saturday ahead of an advancing cold front.
The 500mb trough is now situated across northern Florida with a stationary boundary still draped across Central GA. Low temperatures overnight are forecast to be in the low to mid 60s.
At the surface, a low pressure system will work its way from Wyoming/Colorado to the western Dakotas tonight, then across the eastern Dakotas into Minnesota on Saturday. The frontal boundary associated with the low will exit the area Saturday afternoon, with the precipitation then coming to an end from west to east. High pressure will begin to nose down from the north Saturday night.
356 PM EDT Fri Sep 8 2023 Upper level troughing will keep below normal temperatures in place for the Ohio Valley through the weekend. Nearly stationary H7 trough stretching from the Great Lakes south into the lower Ohio Valley will keep moisture and cool temperatures in place overnight. There is some signal for fog development in the lower Scioto Valley. Weak disturbance lifting northeast ahead of the mid-level trough will increase shower chances in the far southeast Saturday afternoon.
128 PM EDT Fri Sep 8 2023 (Today and tonight) An upper low in the base of a longwave trough will move from south-central Georgia this morning to northeast Florida this afternoon. This corresponds roughly with the expected southern extent of a cold front this afternoon. So within the moister air mass to the south, PW values are high enough to support deep, moist convection, especially with added lift from the upper low, the cold front, and our more routine seabreeze-inspired sources of lift. Back in the drier air north of the front, the air mass will not be any cooler, but it will be drier.