Aikyam-Lab/Synoptic-Bench huggingface dataset:
Forecast remains on track for temperatures tomorrow to be right around normal for this time of year, or slightly warmer, especially elevated locations farther inland. (This evening through Thursday) Quick check of current temps shows about 15-30 degrees cooler than 24 hours ago, depending on where you are. All thanks to a deep marine layer and robust onshore flow in response to a passing upper level trough in the Pacific Northwest. This pattern evolves rather quickly back to a ridge setup with effects beginning Thursday.
Above normal temperatures and dry conditions will continue to be the main story with high pressure dominating the Southwest. /Canada border today, but shouldn't bring any impacts to Arizona due to the impressive ridge that has settle across the Southwest. This area of high pressure will wobble around day-to-day, but ultimately our story won't alter much. The previously mentioned upper-level ridge looks to weaken, but still remain in place over Arizona. The ECMWF model does show a large trough sweeping in from off the Pacific Northwest Coast by the first weekend in October. VFR conditions persist through the period with FEW cumulus clouds over the high terrain.
Highs were significantly cooler for the coastal valleys and coasts, with widespread 70s and 80s for warmer valleys. Temperatures are expected to trend warmer (2-4 degrees) Thursday and Friday as high pressure strengthens over the region. ***From Previous Discussion*** Cooler than normal temperatures are expected to continue through the weekend for coast and valleys as a trough lingers along the West Coast.
The string of mainly clear and warm days with cool nights will continue with this high pressure ridge in control. There may be just enough moisture and cooling aloft with a wave passing well to our north to pop a few afternoon cumulus on the mountain ridges but there will virtually be no chance of precipitation through Thursday night. By Friday, the high pressure will have retrograded to the west over the Desert Southwest with the ridge extending north over the Intermountain West to southern Idaho and Wyoming.
(Thursday through Friday) Mostly quiet weather is anticipated for the short-term, now that the trough and cold front have moved through the region. Afternoon highs should range in the low to mid-80s, with lows tonight dropping into the upper-50s and low- 60s. However, by Friday morning, rain chances will begin to increase, as Hurricane Helene finally begins to interact with the closed low to our north in a Fujiwara effect.
Thus the lower starting point will be good for up to 6 degree cooling trend off yesterday's maxes with the largest delta being over the southern counties.
1250 AM CDT Thu Sep 26 2024 (Tonight through Thursday night) A few showers and thunderstorms will develop along a southward advancing cold front through early evening. North to northeasterly winds will bring in drier air overnight, but the relatively cooler air is nowhere to be found. Sadly, this front won't bring significant relief in terms of afternoon temperatures, however, it will bring much-needed cooler and more comfortable mornings for the region both tonight and Thursday night.
Later today, mid to upper level troughing to the east will transition to a cut-off low and slowly meander to the southeast of the forecast area. This cut-off low will slowly continue to fill.
Rainfall totals overnight will average another 2 to 4 inches, with locally higher amounts, especially in the higher elevations of NE GA. For overnight and early Friday, areas north of the Interstate 20 corridor should see the highest winds.
At this time the remnants of Helene should merge with an upper low that is currently northwest of the area. This low should slide west a touch by Friday night, giving the area a reprieve from the rain, but the cloud cover will remain.
1228 AM CDT Thu Sep 26 2024 - Warmer than normal temperatures through the end of September. - Much cooler, but near normal, into early October. Tonight, high pressure will provide clear skies and calm conditions across much of the region.
Low pressure will then linger in the Ohio Valley through the weekend keeping conditions unsettled. Upper low over the lower Ohio Valley will drop south into the mid South today. A disturbance rotating around the low will move westward across the southern part of the forecast area this afternoon. The remnants of Helene will lift north and then curl northwest, passing south of the forecast area, as it gets absorbed into the preexisting upper low which will be shifting into the Tennessee Valley. For Friday night, the remains of Helene continue to push west of the area as it gets wrapped up into the mid level low in the lower Ohio Valley.
- Mostly dry by afternoon seasonable temperatures ------------------------------------------------------------------- Minor height rises are expected today as the area remains stuck between a northern upper low, moving across southern Canada, and a western upper low, which will slowly dig toward the Tennessee valley today. In addition, a weak cold front will be forced southward through the region as the flow aloft becomes more northerly. Ensemble means suggest rain chances starting Friday morning south of Pittsburgh with the initial outer bands of the large area of low pressure. Other higher-resolution model forecasts are slower and farther west with the low track, which favor the outer bands staying south of the region.
A large upper-level ridge currently dominates the Rockie Mountains with the high pressure system stretching over SW Kansas. The east- central CONUS has an upper-level low pressure system. The ridging present over the Rockies has vertical continuity with highs throughout the entire atmospheric column. Both ensembles and various models depict a holding pattern with the upper- level ridging maintaining itself over the forecast period for at least the next few days.
Mid level ridge will build over the region with dry, clear skies. \/Hodanish Will see energy pass to the north and with the previously mentioned upper low trying to retrograde back west across the Central CONUS at the start of the period. While still above normal, slightly cooler temperatures are expected across the region on Friday given some slight push of colder air during this time frame. Precip chances still look to be low on Friday with some ridging in place, but with some slight increases in moisture and focus Friday afternoon, there does appear to be some slight increase in precip potential over the higher terrain.
Early morning satellite imagery/RAP analysis showed the circulation around a closed low spinning over western TN and western Kentucky. This evening while the closed low is over northern Mississippi it will help draw rain associated with Helene south and into our northern zones. Otherwise, temperatures will continue to be cooler than normal through the period.
(Today through Friday) Key Messages: - Hazardous marine/coastal conditions expected through the weekend Conditions will continue to dry out behind the front yielding highs in the lower 90s today with lows in 60s across the region! Exciting right? We can enjoy that the next couple nights with light and variable winds. There after due to 10-12 second period swells associated with Hurricane Helene in the eastern Gulf of Mexico, those Small Craft Advisory conditions will persist mainly in the offshore waters with minor coastal flooding possible during the high tide cycle. With seas remaining agitated the high risk of rip currents will also be extended through the weekend.
Surface ridging and strong northerly flow aloft keep skies clear and temperatures seasonal for today. Synoptic high pressure to the north with another high omega blocking to the west halts Helene's progress producing both an interesting binary orbiting effect with the antecedent low and eventual merger of the two systems. Recent model guidance has leaned toward a more eastward track for the merged low and a slightly further eastward push of the blocking high across the Rockies.
Conditions are forecast to deteriorate overnight into Thursday morning as the cyclone intensifies, moving north- northeastward over the eastern Gulf of Mexico. Hi- res guidance depicts the highest lightning chances focused near the coast or just offshore.
(Today through Friday Night) Drier and cooler weather is brought to you by yesterday's FROPA that has left behind N/NW winds. Expect these winds to continue pulling in slightly cooler air through the short-term period, resulting in highs in the 80s to low 90s today and Friday. In addition to the cooler temperatures, a tightening pressure gradient will create breezy conditions through tonight, particularly along the coast.
1258 AM CDT Thu Sep 26 2024 A few showers continue along the plateau where the cold front stalled out. To our northwest, the upper low is spinning in place near PAH with a few showers north of our area. (Today through Tonight) A cold front has pushed eastward through Middle TN with latest obs showing it just east of the Plateau. In the wake of this front, temperatures will be cooler with forecast highs in the 70s to near 80. In the wake of the cold front and with cloudy skies, instability will be less with CAPE values forecast to be less than 1000 J/kg.
Some lake breezes off both Great Lakes should moderate temps in the low to mid 70s by the lakeshores, but highs in the interior will peak in the mid to upper 70s. All in all, today should be a nice fall day! Upper air pattern consists of a 500 mb closed low of Hurricane Helene in the Gulf of Mexico, a closed low over the mid Mississippi Valley, and a closed low over southwest Quebec with a trough in the Pacific NW and a ridge in the southern Rockies into the northern Plains 12z Thu. The ridge builds into the upper Great Lakes Thu night through Sat and will bring dry and warm weather to the area.
Winds have decreased and will remain calm through the night, thus cannot rule out isolated pockets of fog within the cooler spots of region (but should not be a big deal even so). High pressure continues to slide into the region tonight and holds across the region through Thursday (and likely well beyond). Pattern Forecast: At the start of the period Thursday night, upper- level ridging is expected to be parked across the north-central tier of the CONUS atop upper-level closed low pressure over the lower MS Valley. Tropical remnants eventually get absorbed into that larger scale upper wave by later Friday, but struggles with much in the way of northward progress as ridging overhead locally keeps much of that energy and associated moisture suppressed to the south across the OH/TN Valleys through the weekend.
1224 AM MDT Thu Sep 26 2024 UPDATED AVIATION SECTION An upper level trough continues to move onshore this evening with its associated Pacific cold front currently pushing into far NW MT.
(Today through Friday) The passage of a cold front this morning will bring drier conditions and gusty winds this afternoon, with a minor impact on temperatures. By Friday afternoon, high temperatures are expected to be back to the low to mid 90s.
Low pressure lingers around the Ohio Valley through the weekend with continued rain chances. The surface pressure gradient will increase as the low moves northwest. By Friday night, the mid level energy that once was Helene will be merging into a synoptic mid level closed low to our southwest. For the upcoming weekend, more opportunities for rainfall will be possible as the center of the mid level closed low slowly rotates east/northeast across Kentucky and Tennessee, weakening and shearing as it goes along.
Expect a gradual warming trend through Friday as high pressure builds over the Desert Southwest.
914 PM MDT Wed Sep 25 2024 An upper level trough continues to move onshore this evening with its associated Pacific cold front currently pushing into far NW MT.
Models continue to be in great agreement with the low off to our northwest stalling out and essentially pulling Helene's low towards it.
1205 AM CDT Thu Sep 26 2024 (This evening through Thursday) High temperatures will be slightly cooler today in the wake of a cold front, topping out near seasonal averages in the low-to-mid 80s. Broad high pressure to the northeast will allow for clear skies and light northeasterly winds to persist into this evening. Light winds will turn clockwise and become westerly by Thursday morning as the high moves further away from our area. However, sunny skies will continue tomorrow and slightly higher upper level heights will allow for high temperatures to be a few degrees warmer than today.
Meanwhile, water vapor satellite imagery shows an upper level ridge dominating most of the southern and central CONUS. Expect highs today in the low to mid 80s and lows tonight once again in the mid to upper 50s.
Early this morning, a mid-level ridge stretched from the Desert Southwest to the Northern Plains with a stagnant closed low spinning over the mid-Mississippi Valley. While the main weather focus is on Hurricane Helene as it intensifies in the Gulf, benign weather continues across the forecast area with the aforementioned ridge in place. Highs will top out in the low to mid 80s. As Helene tracks north, it will be ingested by the closed low over the lower Mississippi Valley and nudge the ridge back towards the Four Corners.
455 AM EDT Thu Sep 26 2024 A weak cold front will gradually move east today as high pressure briefly builds into the Great Lakes region this afternoon. A weak cold front continues to progress eastward this morning, with modest 850-925mb moisture and frontogenesis leading to some scattered rain showers generally south of a KMFD-KCLE-KERI line. Should see these showers dissipate as the front departs to the southeast and high pressure builds into the Great Lakes region, skirting the northern part of the forecast area this afternoon into tonight. The remnants of Helene will settle over the Ohio Valley with the upper low beginning to creep north or east into the area during the short term period.
A cold front moved through the Northern Rockies last night. Temperatures this afternoon will be around 20 degrees cooler compared to yesterday, as temperatures across western Montana will be in the 60s and 70s and north central Idaho having readings in the 70s and 80s.
Synoptically, a potent upper closed-low/trough was positioned over the the Mid-MS Valley Region with upper ridges over the Srn Plains stretching Nwrd into the Cntrl Plains and off the E coast, respectively. On Friday, the remnants of Helene will merge with the closed-low providing additional moisture to the closed-low/trough.
258 AM PDT Thu Sep 26 2024 Expect a gradual warming trend through Friday as high pressure builds over the Desert Southwest.
357 AM PDT Thu Sep 26 2024 Expect a gradual warming trend through Friday as high pressure builds over the Desert Southwest.
Above normal temperatures and dry conditions will continue to be the main story with high pressure dominating the Southwest. /Canada border today, but shouldn't bring any impacts to Arizona due to the impressive ridge that has settle across the Southwest. This area of high pressure will wobble around day-to-day, but ultimately our story won't alter much. The previously mentioned upper-level ridge looks to weaken, but still remain in place over Arizona. The ECMWF model does show a large trough sweeping in from off the Pacific Northwest Coast by the first weekend in October.
626 AM CDT Thu Sep 26 2024 (Today through Friday Night) Drier and cooler weather is brought to you by yesterday's FROPA that has left behind N/NW winds. Expect these winds to continue pulling in slightly cooler air through the short-term period, resulting in highs in the 80s to low 90s today and Friday. In addition to the cooler temperatures, a tightening pressure gradient will create breezy conditions through tonight, particularly along the coast.
Temperatures should be about 5 to 10 degrees cooler than yesterday. A building upper ridge centered over the 4 corners region will push north and expect yet another warmup Friday with highs back into the low to mid 80s valleys and 70s mountains so the trend of very warm conditions continues in the short term. Will have light winds Friday under high pressure.
457 AM CDT Thu Sep 26 2024 (Thursday through Friday) Mostly quiet weather is anticipated for the short-term, now that the trough and cold front have moved through the region. Afternoon highs should range in the low to mid-80s, with lows tonight dropping into the upper-50s and low- 60s. However, by Friday morning, rain chances will begin to increase, as Hurricane Helene finally begins to interact with the closed low to our north in a Fujiwara effect.
622 AM CDT Thu Sep 26 2024 (Today through Friday) A cold front that was responsible for the development of a few scattered showers and even an isolated strong/severe storm or two continues to push south and east into the Gulf of Mexico this morning. Oh, and cooler temperatures with heights/thicknesses aloft dropping in response to the ULL trying to make it's way a bit closer to the CWFA.
636 AM EDT Thu Sep 26 2024 A weak cold front will gradually move east today as high pressure briefly builds into the Great Lakes region this afternoon. A weak cold front continues to progress eastward this morning, with modest 850-925mb moisture and frontogenesis leading to some scattered rain showers generally south of a KMFD-KCLE-KERI line. Should see these showers dissipate as the front departs to the southeast and high pressure builds into the Great Lakes region, skirting the northern part of the forecast area this afternoon into tonight. The remnants of Helene will settle over the Ohio Valley with the upper low beginning to creep north or east into the area during the short term period.
630 AM CDT Thu Sep 26 2024 (Today through Friday) Key Messages: - Hazardous marine/coastal conditions expected through the weekend Conditions will continue to dry out behind the front yielding highs in the lower 90s today with lows in 60s across the region! Exciting right? We can enjoy that the next couple nights with light and variable winds. There after due to 10-12 second period swells associated with Hurricane Helene in the eastern Gulf of Mexico, those Small Craft Advisory conditions will persist mainly in the offshore waters with minor coastal flooding possible during the high tide cycle. With seas remaining agitated the high risk of rip currents will also be extended through the weekend.
339 AM MDT Thu Sep 26 2024 KEY MESSAGES: - A cold frontal passage will result in gusty winds and critical fire weather conditions for much of the area today.
The upper level ridge will be positively tilted over the Tri-State area as an upper trough swings over the Northwest CONUS. The ridge will remain the dominant feature over the region through the overnight hours tonight before the trough slides over the High Plains on Friday. Overnight Friday, the upper ridge is expected to strengthen once again over the Western CONUS and quickly push the trough further east.
716 AM EDT Thu Sep 26 2024 Rain showers with a few embedded thunderstorms will continue today as a cold front moves across the region. Rain chances will once again increase by midweek as the next cold front approaches the area. Another unsettled period once again expected today as an elongated area of low pressure and associated front continue to impact the region. Mainly dry and warm conditions expected through the short term as high pressure takes hold of the area.
616 AM CDT Thu Sep 26 2024 (Today and tonight) An upper level ridge will hang out to our west today resulting in a rise in thickness values and therefore higher temperatures this afternoon. We will see a return to surface pressure troughing in lee of the Rockies bringing light surface winds around to the southwest.
Sustained surface winds are expected to range from 30 to 40 mph with frequent gusts near 50 mph, especially in the Lower and Middle Keys. Thundery squalls may produce localized wind gusts of 55 to 65 mph, and could result in damage to property and dangerous crosswinds along bridges. Troughing over the eastern U. will pull Helene inland over the end of the week and into the weekend, and Atlantic ridging will have the opportunity to take control of the forecast area. Major saltwater flooding of 1 to 3 feet above ground level at the lowest elevation areas and shoreline is expected from early Thursday morning through late Thursday evening, with strong southeast to south winds impacting the Florida Keys, as Hurricane Helene moves northward through the eastern Gulf of Mexico and intensifies into a major hurricane.
618 AM EDT Thu Sep 26 2024 Rain showers with a few embedded thunderstorms will continue today as a cold front moves across the region. Rain chances will once again increase by midweek as the next cold front approaches the area. Another unsettled period once again expected today as an elongated area of low pressure and associated front continue to impact the region. Mainly dry and warm conditions expected through the short term as high pressure takes hold of the area.
631 AM CDT Thu Sep 26 2024 (Today through Friday) The passage of a cold front this morning will bring drier conditions and gusty winds this afternoon, with a minor impact on temperatures. By Friday afternoon, high temperatures are expected to be back to the low to mid 90s.
An upper level trough is moving through the area, bringing onshore flow this morning. This onshore push is also bringing cooler temperatures across much of the Valley and foothills, generally 5-10 degrees lower than this time yesterday. Near average high temperatures are generally expected again today, though the onshore flow will weaken this morning as the trough exits to the east. High temperatures increase significantly on Friday across the area, due high pressure ridging centered over the Four Corners area expanding into interior NorCal.
The highest rain chances (50-90%) are Friday afternoon across south-central Missouri and the eastern Ozarks. Clouds return tonight making it feel a bit warmer in the upper 50s.
The eastern H500 trough remains cutoff over the lower Ohio valley, with Hurricane Helene making landfall tonight along the Florida Panhandle Coast. Conditions will remain rather quiet and calm for our region as broad ridging holds over the west-southwest CONUS. Through Friday morning, Hurricane Helene will merge with the eastern trough, lifting quickly to the north across the eastern CONUS, bringing record rainfall to portions of Georgia, the Carolinas, and into Tennessee along the Appalachian Mountains. Through the weekend, temperatures will warm above normal, as the central Plains into the upper Midwest is opened to persistent southwesterly flow as brief steep ridging sets up off the southwestern CONUS to the western Great Lakes.
1240 PM CDT Thu Sep 26 2024 (Today through Friday Night) Drier and cooler weather is brought to you by yesterday's FROPA that has left behind N/NW winds. Expect these winds to continue pulling in slightly cooler air through the short-term period, resulting in highs in the 80s to low 90s today and Friday. In addition to the cooler temperatures, a tightening pressure gradient will create breezy conditions through tonight, particularly along the coast.
204 PM MDT Thu Sep 26 2024 Breezy conditions and mild temperatures will continue through the rest of today with warmer conditions expected over the weekend.
1230 PM CDT Thu Sep 26 2024 (Today and tonight) An upper level ridge will hang out to our west today resulting in a rise in thickness values and therefore higher temperatures this afternoon. We will see a return to surface pressure troughing in lee of the Rockies bringing light surface winds around to the southwest.
Dry conditions and warmer than average temperatures prevail for the next several days. The ridge that has been over Central California for the last few days will continue to be stuck in place for the next several days due to the tropical system, Hurricane Helene, in the Gulf of Mexico. There will be a slight decrease in daytime temperatures today due to the passing of a weak trough through Washington this morning, after which the ridge will build back into the area.