Aikyam-Lab/Synoptic-Bench huggingface dataset:
A cold front will bring a northerly wind shift this afternoon, but it is not expected to prevent high temperatures from rising about 5 to 7 degrees over yesterday's readings for most locations. A general dry northwesterly flow will continue over the Northern Rockies as upper level ridging builds over the Pacific Northwest. Elevated H850 - H700 winds have resulted periods of gusty overnight west to northwest surface winds over ridge tops and even some lower elevations/valleys along the Rocky Mountain Front. Highs today will be about 5 to 7 degrees warmer for most locations south of the Hi-Line despite an expected cold frontal passage. Some cooler air in the wake of the front will bring a temporary dip in temperatures for Thursday, mostly over the plains.
High pressure is building across the pacific northwest, boosting daytime high temperatures into the 90s across Idaho and western Montana.
417 PM EDT Wed Aug 11 2021 Warmth, humidity, and periodic showers and thunderstorms can be expected until cold frontal passage late this week. Aftn convection is waning for most areas with passage of the support vort center/possible MCV, but additional storms continue to fire in the convergence zone/outflow boundary near I 70 as sly flow intensifies on the van of the upstream trough.
A wave in the NW flow aloft will bring a cold front south this afternoon with gusty NW winds that will continue into this evening. Thursday will be cool day with high pressure over the area.
High temperatures in the low-mid 90s and overnight lows in low-mid 70s. Expect temperatures tonight to once again be in the low to mid 70s.
337 PM CDT Wed Aug 11 2021 H5 analysis from earlier this morning had high pressure anchored off the Carolina coast. This area of high pressure extended west across the southeastern CONUS. Northwest of this feature, closed low pressure was located over northern Manitoba with a trough of low pressure extending south southeast into Minnesota and northern Wisconsin. West of this feature, high pressure was anchored off the coast of Washington with a ridge extending into southeastern Alaska. At the surface, a weak cold front extended from the arrowhead of Minnesota, into east central Nebraska and northwestern Kansas. Lows tonight will be seasonal with readings in the lower 60s.
310 PM CDT Wed Aug 11 2021 Skies are mostly sunny with temperatures in the low to mid 90s. High pressure remains along the Tennessee/North Carolina border. The high will not move much tonight with dry weather continuing.
231 PM MDT Wed Aug 11 2021 Upper air analysis shows an upper low over Manitoba, with the upper ridge over the west coast, and northwest flow aloft over our region. This will lead to slightly cooler temperatures Thursday and a higher relative humidities.
234 PM CDT Wed Aug 11 2021 Cooler and breezy on Thursday with highs in the 70s expected.
A cold front drops south across eastern Colorado Thursday morning. Initially, the air behind the front won't be that much cooler. Highs Thursday are expected to be in the upper 80s to lower 90s, about 4-6 degrees cooler than today. Will have the highest PoPs here.
1240 PM CDT Wed Aug 11 2021 High pressure continues over the area today. Upper ridging will continue to be the dominant weather feature. As has been the case the last few days, the highest dewpoints will be clustered around the Delta region, and thus, we're expecting the highest HX values in those locations. And, interestingly enough, the models have come back a degree or so cooler.
The highest coverage of showers and storms this afternoon is across the Treasure Coast and Lake Okeechobee, where the sea breeze and lake breeze have interacted. The highest rain chances will focus along the Treasure Coast and Lake Okeechobee, with slightly lower rain chances across the north.
339 PM EDT Wed Aug 11 2021 Warmth, humidity, and periodic showers and thunderstorms can be expected until cold frontal passage late this week. Early aftn convection is waning for most areas with passage of the support vort center/possible MCV, but additional storms continue to fire in the convergence zone/outflow boundary near I 70 as sly flow intensifies on the van of the upstream trough.
1153 AM CDT Wed Aug 11 2021 Rest of today: Persistent S-SW return flow on the W periphery of the Atlantic subtropical ridge continues. With thermal profiles only slightly cooler, persistence fcst in mid- upper 90s is expected.
A more substantial cold front arrives early evening (possibly late afternoon in some areas) shifting winds to the north for the evening hours and bringing much cooler conditions for Thursday. Chambers Another warm, dry and breezy day can be expected today, ahead of a cold front dropping in from the north this evening. Behind the cold front, a few showers are possible over northeastern areas overnight. Cooler conditions and easterly winds can be expected on Thursday in the wake of the front with highs in the 70s to lower 80s.
434 PM EDT Wed Aug 11 2021 High pressure will remain anchored off the Mid Atlantic coast this week, resulting in typical summer conditions.
249 PM EDT Wed Aug 11 2021 High pressure will remain anchored off the Mid Atlantic coast this week, resulting in typical summer conditions.
/DC/ Rest of today: Persistent S-SW return flow on the W periphery of the Atlantic subtropical ridge continues. With thermal profiles only slightly cooler, persistence fcst in mid- upper 90s is expected.
High temperatures will be in the low to mid 90s with lows in the low to mid 70s. Expect temperatures tonight to once again be in the low to mid 70s.
255 PM CDT Wed Aug 11 2021 Another warm day is underway across the TN Valley as high temperatures begin to crest in the low to mid 90s with dew points in the mid 70s. Otherwise, temperatures should cool into the low to mid 70s tonight.
With this, interior locations are running a few to as much as 6 deg F warmer compared to 24 hours ago as high pressure builds over the region. High pressure will then build over the Great Basin late in the week and nudge toward the California coast over the weekend.
254 PM CDT Wed Aug 11 2021 Heat continues to be the highlight of the short term, with continued chances mainly for afternoon showers and thunderstorms through the forecast. 850 mb temps of 20C-22C allowing for highs in the mid 90s, and continued southwesterly flow at the surface keeping dewpoints in the low to mid 70s. Winds picked up a bit more this afternoon, and likely allowed for some additional low level mixing which helped lower dewpoints to the low 70s for most. For Thursday, highs are expected to be a degree or two warmer for most areas, with little change to the dewpoints, so have the heat advisory continuing tomorrow as well.
500mb ridge will be building over the Eastern Gulf while a 500mb trough resides over the Inter-mountain West.
The primary features of interest with the large scale pattern include a closed low near the border of KY/OH/IN and another closed low over Alberta Canada. The low over Canada was embedded in a trough that extended down into WA and OR. Generally tried to use the ESRL HRRR to provide some detail to the precipitation forecast for today, which suggests a band of showers and scattered thunderstorms lifting north across the area this morning and afternoon ahead of the upper low. That should allow highs to warm into the lower and mid 80s. The highest instability should stay mostly to our west and south, but we will have higher bulk shear.
1212 AM EDT Fri May 22 2020 A low pressure system moving through the Ohio Valley will bring increased cloudiness and rain to the area through Friday. A closed low across the TN Valley region should to move north to the lower OH Valley by morning. Increasing moisture and ascent ahead of the low should result in scattered showers across the region overnight. The low should be just east of the area Saturday, though still in close enough proximity to result in low shower chances through the day.
113 AM EDT Fri May 22 2020 High pressure will maintain dry and seasonably warm conditions across the North Country through the holiday weekend.
Expect scattered to broken cloud cover over the area going into tonight as southeasterly flow brings in moisture from a nearly stationary low pressure system over the Ohio River valley Region. Right now it appears later Friday night and through the day Saturday will see fairly widespread rainfall with perhaps a small break in the action Saturday evening/night as the Mid-level trough exits northeast of the area.
Lingering clouds and precip will have an impact on daytime highs and have gone on the cooler side of guidance for high temperatures most areas. That being said, if the southeastern portions of the forecast area can get some clearing along with some advection of higher dewpoints later this afternoon, then the timing of the approach and passing of the upper trof axis could bring a window for strong storms across the far southeast, primarily the I35 corridor and points southward. Redevelopment of storms on Saturday later in the afternoon is anticipated to shift the focus toward the western and north central portions of the forecast area, as convection develops along the dryline in the high plains and propagates north northeastward in the late afternoon and evening hours.
H500 cutoff low along the KY/TN border will begin to lift northeastward as swrly flow across the middle of the country is enhanced by a persistent area of low pressure near the Pacific NW. At the sfc, a warm front will remain south of the state for a bit longer before making its way northward on Friday. Ahead of this warm front, Td values have remained in the 60s F with >70 F values south of the state line, not far away.
A backdoor cold front will move through the region Saturday knocking temperatures back into the 60s for the weekend.
Low pressure and an inverted trough begin to push into the region on Saturday. A departing upper low and lack of additional forcing along with decent capping out west will hold off showers and thunderstorms through the afternoon. Upper level trough over the western northern plains will lift to the northeast Saturday night.
305 AM EDT Fri May 22 2020 Periodic showers are expected today with crossing low pressure. A closed low is expected to move across the OH Valley region today, around the NW periphery of an upper high off the East Coast. Scattered showers are expected to continue tonight as the low crosses the Upper Ohio Valley region. Isolated showers are possible Saturday, mainly E of I 79, with the area in close proximity to the low.
As of this afternoon, the pattern over the CONUS remains dominated by the closed upper low over the Ohio River Valley and a broad trough over the western US. A break in the precipitation looks likely during at least the morning on Saturday as a weak upper ridge moves into the Plains.
300 AM MDT Fri May 22 2020 Synoptic Setup: A large ridge of hot high pressure runs from the Desert Southwest up through Colorado and into the Dakotas while a large trough exists over the Pacific Northwest.
300 AM MDT Fri May 22 2020 The latest analysis shows an upper trough extending southward into the pacific northwest from an upper low over southern Alberta. The southeasterly upslope flow in a region of positive theta-e advection, combined with an approaching upper trough, will bring isolated to scattered showers and thunderstorms over northeastern Wyoming this evening, spreading eastward and increasing in coverage tonight and on Saturday.
Upper trough over the northern Rockies will lift northeast, with a second wave following out of Wyoming for late Saturday.
334 AM CDT Fri May 22 2020 An upper trough over the NW US this morning will swing down across the Great Basin today reaching the Northern Rockies Saturday.
332 AM EDT Fri May 22 2020 High pressure will maintain dry and seasonably warm conditions across the North Country through the holiday weekend.
The area will be situated on the western periphery of a stacked ridge of high pressure today. This convergent flow, along with instability inland from temperatures warming up to the low-mid 90s today is anticipated to kick up both an Atlantic and Gulf coast seabreeze in the afternoon. The highest coverage of thunderstorms along the I-75 corridor where the two fronts are most likely to converge.
1214 AM CDT Fri May 22 2020 High pressure to our east along with low pressure developing over the high plains will continue to produce moisture into the area from the south. Temperatures to remain on the warm side during this time frame with the warm air moving into the area, and afternoon highs should get back into the low 70s on Friday.
Shower activity will continue to dwindle this morning as the low exits the area. Friday and Saturday will be mostly dry as high pressure takes over.
709 AM EDT Fri May 22 2020 High pressure will maintain dry and seasonably warm conditions across the North Country through the holiday weekend.
531 AM MDT Fri May 22 2020 The latest analysis shows an upper trough extending southward into the pacific northwest from an upper low over southern Alberta. The southeasterly upslope flow in a region of positive theta-e advection, combined with an approaching upper trough, will bring isolated to scattered showers and thunderstorms over northeastern Wyoming this evening, spreading eastward and increasing in coverage tonight and on Saturday.
Water vapor satellite imagery early this morning, depicts a digging upper level trough over Oregon, while our region is generally under weak cyclonic or counter-clockwise flow. The upper level low over Oregon will eventually pinwheel into southern Idaho Friday night, and then briefly stall over northwest Wyoming. While this will bring snow to the higher elevations there, it appears that much of our region will escape the bulk of the precipitation Saturday.
This boundary is expected to slowly move northward across Alabama over the next 24 to 36 hours as a warm front. I have the highest pops for this morning across the north as a result. Otherwise, look for warmer temperatures through Saturday with the increase in warm southerly flow off of the Gulf.
As the low moves over eastern NE Sat morning, brief ridging will follow giving us a dry Sat morning. Broad lee troughing extends southward from the Blackhills along the High Plains. A lot of smaller systems are at play here and that is the tricky part, especially given the abundance of moisture ahead of the trof.
1037 AM EDT Fri May 22 2020 High pressure will maintain dry and seasonably warm conditions across the North Country through the holiday weekend.
With cloud cover persisting over this northeast corner, temperatures should stay slightly cooler compared to the rest of the region. Some stratus and fog will be possible after midnight, with temperatures falling into the low 50s. Lee troughing develops in eastern Colorado as an upper trough pushes onto the Rockies. The models continue to show an amplified upper-level ridge over the Great Lakes region and upper-level trough deepening over the Rockies.
636 AM CDT Fri May 22 2020 High pressure to dominate the wx tdy. Guidance has backed off considerably on precipitation today with only a couple of the high res guidance showing any development at all.
413 AM CDT Fri May 22 2020 Forecast remains challenging thanks to stagnant upper low which is still spinning over the Ohio Valley. That said, clouds will remain stubborn, especially east of the James Valley where moist/cool east-southeast low level flow continues to draw from the stuck upper low to our east. With the overall slower progression of the upper level pattern, Saturday could see the chance of spotty showers and cooler temps linger across our east into the afternoon.
Atlantic ridge extending across the area and sea breeze developing into the afternoon will produce E/SE winds across the waters up to around 10 knots.
High temperatures this afternoon will range from the low 80s north to the upper 80s south with low tonight in the mid to upper 60s. Although upper ridge building over the area the air mass remains moist and moderately to strongly unstable with steep low to mid level lapse rates. There may be a weak short wave trough trigger moving to the southeast in northwest flow aloft.
301 AM MDT Fri May 22 2020 Synoptic Setup: A large ridge of hot high pressure runs from the Desert Southwest up through Colorado and into the Dakotas while a large trough exists over the Pacific Northwest.
With cloud cover persisting over this northeast corner, temperatures should stay slightly cooler compared to the rest of the region. Some stratus and fog will be possible after midnight, with temperatures falling into the low 50s. Lee troughing develops in eastern Colorado as an upper trough pushes onto the Rockies.
Some mid and high clouds are slowly drifting south through NorCal early this morning ahead of a mostly dry cold front.
955 AM CDT Fri May 22 2020 The first wave has moved east of the CWA this morning with trailing convection in the vicinity of a broad warm frontal zone lifting north across the Mid-South. /issued 251 AM CDT Fri May 22 2020/ A cut-off closed upper low over the Ohio Valley will finally lift out today, allowing stronger westerlies to return to the Midsouth. In the interim, a warm front will lift through northeast AR and west TN this afternoon, perhaps providing focus for storms. NAM Bufr soundings depict MUCAPE in excess of 3000 J/KG in the vicinity of the warm front, accompanied by 3KM bulk shear of 30 knots. Saturday will see robust upper level ridging centered over GA, and isolated showers and pulse thunderstorms under the western periphery of this strong ridge.
A dry cold front will lower afternoon highs today slightly, and gusty winds are forecast to occur in the Kern County Deserts by this afternoon.
959 AM EDT Fri May 22 2020 Periodic showers are expected today with crossing low pressure. An adjustment was also made to the temps as a few locations to the north will cross the 70 degree mark for highs with more southern locations getting slightly warmer than suggested by MOS guidance. Scattered showers are expected to continue tonight as the low crosses the Upper Ohio Valley region. Isolated showers are possible Saturday, mainly E of I 79, with the area in close proximity to the low.
Guidance has backed off considerably on precipitation today with only a couple of the high res guidance showing any development at all.
518 AM EDT Fri May 22 2020 Periodic showers are expected today with crossing low pressure. A closed low is expected to move across the OH Valley region today, around the NW periphery of an upper high off the East Coast. Scattered showers are expected to continue tonight as the low crosses the Upper Ohio Valley region. Isolated showers are possible Saturday, mainly E of I 79, with the area in close proximity to the low.
1038 AM EDT Fri May 22 2020 Water vapor imagery reveals a broad long wave trough across the Gulf of Mexico and extreme Western Caribbean. High pressure centered just to the north of Bermuda reaches to the west-southwest across north-central Florida. 7") for the date, the lower tropospheric moisture from the SFC through 800 mb is meager, with dewpoint depressions 5 to 7 degC. We will retain the inherited forecast which calls for only 20% chances for rain and thunder through the afternoon, which represents the low end of the MOS consensus. A western Atlantic ridge axis will linger across Central Florida for the next several days.
As the low moves over eastern NE Sat morning, brief ridging will follow giving us a dry Sat morning. Broad lee troughing extends southward from the Black Hills along the High Plains. A lot of smaller systems are at play here and that is the tricky part, especially given the abundance of moisture ahead of the trof.
A backdoor cold front will move through the region Saturday knocking temperatures back into the 60s for the weekend. Further KGYX 12Z sounding shows an exceptionally dry layer through the lower atmosphere supporting further drying through the day.
The low-level drier air is lake-influenced and will gradually moisten up this afternoon. As the day goes on, we may see some breaks in the clouds across southern WI as the mix out the lowest layers of the atmosphere, although confidence is low. High temperatures are expected to be around 70 well inland, despite the clouds, and in the lower 60s near Lake Michigan with the persistent onshore flow.
635 AM CDT Fri May 22 2020 Forecast remains challenging thanks to stagnant upper low which is still spinning over the Ohio Valley. That said, clouds will remain stubborn, especially east of the James Valley where moist/cool east-southeast low level flow continues to draw from the stuck upper low to our east. With the overall slower progression of the upper level pattern, Saturday could see the chance of spotty showers and cooler temps linger across our east into the afternoon.
/issued 251 AM CDT Fri May 22 2020/ A cut-off closed upper low over the Ohio Valley will finally lift out today, allowing stronger westerlies to return to the Midsouth. In the interim, a warm front will lift through northeast AR and west TN this afternoon, perhaps providing focus for storms. NAM Bufr soundings depict MUCAPE in excess of 3000 J/KG in the vicinity of the warm front, accompanied by 3KM bulk shear of 30 knots. Saturday will see robust upper level ridging centered over GA, and isolated showers and pulse thunderstorms under the western periphery of this strong ridge.
GOES-East satellite imagery depicts mostly clear to partly cloudy skies behind the showers, speaking to the larger influence of low-level ridging and subsidence over the area. This convergent band of showers will bring brief squalls of near 25 knots as it continues to trek west- northwest across the Lower Keys, likely departing by the island chain by sunrise. Concerning the forecast, expect this activity to give way to mostly sunny skies today with only a slight chance PoP as low- level ridging is firmly in control. Deeper moisture should build in this weekend as a series of subtle inverted low-level troughs round the ridge axis that will remain in place over the region.
/issued 334 AM CDT Fri May 22 2020/ An upper trough over the NW US this morning will swing down across the Great Basin today reaching the Northern Rockies Saturday.
748 AM EDT Fri May 22 2020 Periodic showers are expected today with crossing low pressure. A closed low is expected to move across the OH Valley region today, around the NW periphery of an upper high off the East Coast. Scattered showers are expected to continue tonight as the low crosses the Upper Ohio Valley region. Isolated showers are possible Saturday, mainly E of I 79, with the area in close proximity to the low.
124 PM EDT Fri May 22 2020 High pressure will maintain dry and seasonably warm conditions across the North Country through the holiday weekend.
Previous Discussion: Synoptic Setup: A large ridge of hot high pressure runs from the Desert Southwest up through Colorado and into the Dakotas while a large trough exists over the Pacific Northwest.
On Saturday, after some showers and storms lingering from the overnight into the morning hours, cloud cover will slowly decrease through the day as a result of a ridge in the lower to middle Mississippi River Valleys. A low pressure system in the Central Plains will be diverted towards the Great Lakes as a result of the ridge, keeping precip chances lower for the afternoon.
North winds will be on the increase as a thermal trough develops Friday into Saturday.
Low temperatures are expected to range from the upper 40s to low 50s in the east where winds will be very light to the low 50s along and west of the Colorado/Kansas border. On Saturday all models except the NAM lift a warm front northeast through all but the far northeast and eastern zones by the end of the day with a dryline from near Yuma to Colby and Oakley. High temperatures are expected to reach the low 80s to around 90, highest readings along and west of the dryline. As far as precipitation chances, it appears that isolated thunderstorms will be possible mainly near the warm front in the mid to late afternoon hours from Yuma to Oberlin and Hill City northward.