Aikyam-Lab/Synoptic-Bench huggingface dataset:
Water vapor imagery this afternoon was showing an upper ridge in control over the western half of the CONUS. At the surface, low pressure was centered over SD with a trailing thermal boundary along the SD/NE border. Given this POPs have been trimmed and confined to the lower tier of southeast NE and southwest IA. Friday through Saturday Upper level high pressure strengthening over the central Plains will provide dry conditions with a warming trend over the region. Moisture will be abundant with dew points progged in the lower 70s and precip water values anywhere from 1. At this point the NAM/GFS are in rather good agreement suggesting that relatively weak vertical wind shear coupled with the highly unstable environment will probably translate to storms being multicellular in nature overall with some severe development probable.
Cold front being analyzed across western Montana into southeastern Idaho this morning. Just about everywhere else should remain dry with the lower humidity pushing into the east.
1106 PM EDT Thu Aug 6 2020 A few showers or thunderstorms will be possible in and near the ridges both tonight and tomorrow afternoon, with mainly dry weather elsewhere. Showers/storms will progress eastward out of the area a bit faster on Friday as upper-level steering becomes more orthogonal to the boundary and the upper-level trough lifts off to the northeast. Warmer, drier conditions are anticipated for Saturday.
/DC/ Prior discussion below: Tonight and Friday: The persistent mid level ridge will begin to weaken a bit moving forward as ridging becomes dominant over TX into the northern Gulf of Mexico. The main impact of the ridging will be to warm the column which will continue to suppress convection and allow for slightly warmer temperatures Friday. /GG/ This weekend: Hot and somewhat drier conditions will continue into the weekend as mid/upper ridging over both the Plains and the northern Atlantic builds into the area slightly. The strengthening ridge and continued mixing will result in rather warm conditions over the weekend, with highs solidly into the mid 90s and pushing near the upper 90s.
Upper ridging has moved across the central CONUS, with a trough now pushing onshore the Pac NW coast. Deep southerly low level flow has persisted across the region, ahead of broad low pressure across Montana to Wyoming. Warmer temperatures are expected, with highs in the upper 80s to around 100. A cold front is progged to push across the CWA Friday night as embedded waves within southwest flow aloft push across the CWA. Friday night's cold front will become stationary across south central SD. Low pressure is expected to develop along the front.
The more summer-like weather will be the result of an upper level ridge building over the Southern Plains. The weather pattern will once again become more active mid to late week as the upper level ridge retrogrades to the west.
Broad ridging will persist over the central Plains, with the leeward trough centered over the Ohio Valley gradually lifting east/northeast causing the ridge to stretch from the Rockies to the Atlantic into the Weekend. Through the afternoon, a weak short wave trough continues to slide southeast from NE/IA with a focus of 315K isentropic ascent from over IA in northern Missouri promoting scattered showers and thunderstorms into the afternoon. Heat index values Saturday afternoon will approach the lower 100s F.
High pressure during the weekend shifts east by next work week. Models indicate stronger vorticity values accompanying the passage of the trough axis which will enhance the probability of showers and storms during the afternoon and evening hours. During the night, drier air is expected to enter the area as high pressure builds in behind the trough. Today, high temperatures are expected to reach low to mid 80s in the lowlands and upper 60s to upper 70s in the higher elevations. Lows should be in the 60s across the lowlands and upper 50s to low 60s in the mountains. Exception will be across the higher mountains where enough moisture converge may occur to eek out an isolated diurnally driven shower or storm.
948 PM PDT Thu Aug 6 2020 A cold front has exited Washington and is almost through North Idaho tonight.
In the near term will be watching the evolution of a small cluster of convection over far south central KS into northeast OK near and northeast of a sfc warm front. Can't rule out some additional Friday afternoon activity (similar to today) as the effective warm front lifts northeast into our cwfa. Additional nocturnal/early morning convection will be possible late Friday night into Saturday, again within the elevated frontal zone ahead of the sfc warm front.
At the surface, high pressure across the northern gulf waters will lead to persistent southeast winds across South Texas, pumping in moisture to the region with PWATs of 1.
313 AM EDT Fri Aug 7 2020 A weak cold front remains stalled today across the piedmont. High pressure builds in this weekend with return to typical summer weather. Better support for organized thunderstorms appears to be east of the mountains today, but as upper trough moves closer, low-mid level lapse rates should increase, keeping coverage fairly numerous even in the mountains by early afternoon. We will finally see the front exit the piedmont tonight and slowly experience a little bit of drier weather for Saturday, as high pressure builds in. Similar temperatures tonight as this morning, but maybe a degree or two cooler in the mountains.
H5 trough axis from Toronto to Nashville today will move slowly eastward and bring in drier air aloft while helping usher in some drier surface air in time for Saturday.
The upper level ridge axis will continue to move east, becoming centered over the Mississippi River by Friday evening. At the surface, a cold front extends from South Dakota into Nebraska and slowly moves east. Southeasterly surface flow associated with a low pressure system will bring ample surface moisture into the area. As this moist and unstable air reaches the cold front, there will be ample lift to trigger a line of thunderstorms in the evening.
Here, several weak low pressure areas will slide along the boundary and create just enough lift with northeasterly flow to generate activity this afternoon. Meanwhile across the north, a weak trough at 850 mb is located generally along the I-59 corridor.
348 AM EDT Fri Aug 7 2020 An upper longwave trough will persist over the forecast area through today. For Saturday the trough gets pushed north and east as high pressure builds from the west and from the Atlantic. However GA remains in a weak area between the upper ridges.
1235 AM EDT Fri Aug 7 2020 Expansive high pressure over the Great Lakes region will provide clear skies and calm/near calm winds over southeast Michigan tonight. Sprawling area of high pressure anchored over the region will sustain benign weather conditions over the next 48 hours. Projected 850-925 mb mean thermal layer roughly 1-2 degrees warmer than noted today, netting highs near or just above 80 degrees.
/issued 307 PM CDT Thu Aug 6 2020/ (Tonight and Friday) The short term remains dry, with temperatures warmer than usual, for early August.
Aside from small-ish rain chances through early tomorrow in far northern zones, expect the region to remain mostly clear and dry through midday tomorrow with temperatures slightly warmer and muggier than was the case 24 hours ago.
Summer heat continues through Saturday with temperatures in the upper 90s to about 101, but the Palo Duro Canyon will be a few degrees warmer around 103-106 (warmer today). High pressure aloft nearly centered over Texas will continue through the short term.
For today, a warm front will lift northward across a portion of the FA. 850-hPa temperatures are forecast to increase to 28-30C via a downslope southwesterly component to the low level wind. With the continued warm/capped atmosphere and the ridge starting to build in from the southâ¦ the chance of storms looks unlikely over the weekend.
224 AM MDT Fri Aug 7 2020 Cold front will move to the east this morning. The high will keep skies clear to partly cloudy on Saturday.
VFR conditions are generally expected to prevail over the next 24 hours with the ridging pattern persisting across Deep South Texas. As the ridge axis moves off to the west and moisture increases across the area, isolated showers will be possible Friday morning through the afternoon. Expect VFR conditions to prevail across the Rio Grande Valley tonight into early Fri morning as the 500mb subtropical ridge across northwest Texas continues to provide subsidence across deep south Texas.
High pressure settles over the area late in the weekend. Latest analysis shows an upper level trough to our west, while at the surface a stalled frontal boundary remains across the Mid Atlantic. Otherwise, the upper level trough will slowly progress east today, while the surface boundary will remain in the vicinity of the area.
An upper level trough over the Pacific Northwest has swung inland. A weak upper low has broken off the southern end of the trough and will be over the area today.
/issued 219 AM CDT Fri Aug 7 2020/ Today the subtropical ridge will be expansive and centered INVOF ABI/SJT by 00Z/Sat. To the w of the said ridge center there will be a primary SB instability axis that forms from far SE NM into the NE TX Panhandle while the primary mid-level theta-e ridge axis will extend from SW NM into W TX plains. Sat the subtropical ridge starts to become bifurcated with one center still near ABI and another in nrn Chihuahua, MX. As such there will be only an area from GDP Mtns-W Eddy County favored for a few SHRA/TSRA Sat PM in proximity to the lingering mid-level theta-e ridge.
630 AM EDT Fri Aug 7 2020 A weak cold front will become stationary over central NC today before slowly dissipating late in the weekend. Areas of stratus and fog this morning followed by scattered thunderstorms The mid/upper level trough will continue to weaken and lift out today.
859 AM EDT Fri Aug 7 2020 A few showers and thunderstorms are possible in the vicinity of the ridges this afternoon, with mainly dry weather elsewhere. Building high pressure will create above average temperatures this weekend. Quick update to up PoPs along portions of the southeast ridges, where showers and storms will arrive shortly in a zone of moisture convergence. Showers and isolated thunderstorms will once again develop near and along the ridges late afternoon as the upper-level trough crosses into western PA. Models suggest that the trough axis will be somewhat out-of-phase west of the Laurel Highlands. With the best low-level lapse rates and instability embedded in the ridges, orographic lift may help updrafts sustain some strength before quickly exiting our county warning area. Warm, dry conditions are anticipated Saturday as high pressure builds to our west.
Luckily some breezy conditions today will help temper the heat, as we see a tight gradient ahead of the low pressure system moving towards the area tonight. Much will depend on the timing of the boundary as well as the timing of the low level jet shifting eastward. Saturday night looks to start off active as all models show a boundary across the southern part of the state with a short wave trough moving over the region.
Upper trough continues to weaken with diminishing onshore flow allowing for warming trend, temperatures will warm back to near normal levels today. Highs will be in the lower 90's over the Cent/Southern Sacramento Valley, Northern San Joaquin Valley and Delta and upper 90's Northern Sacramento Valley. This low will bring just enough moisture northward over the Sierra for a few isolated thunderstorms near the crest mainly south of Interstate 80.
419 AM MDT Fri Aug 7 2020 The upper flow pattern becomes more zonal across the continental United States over the next few days with high pressure over the Gulf of Mexico and a series of low pressure systems moving east across the Canadian Rockies and Plains. No precipitation is expected Today and through the day on Saturday with the weak short wave ridging in place aloft. By Saturday evening, a short wave trough aloft moves off the Rockies and across the central High Plains region. That short wave trough is expected to combine with an area of instability extending from northeast Colorado extending across southern Nebraska late Saturday afternoon and evening to produce isolated to scattered thunderstorms with a few storms possibly becoming severe as they move across southern Nebraska during the evening.
Today Through Saturday Night A ridge of high pressure over the southern Plains will become more dominant in Arkansas as the near term progresses. On the eastern periphery of the ridge, a warm front will gradually lift to the north/east.
537 AM EDT Fri Aug 7 2020 A few showers and thunderstorms are possible in the vicinity of the ridges this afternoon, with mainly dry weather elsewhere. Building high pressure will create above average temperatures this weekend. Quick update to up PoPs along portions of the southeast ridges, where showers and storms will arrive shortly in a zone of moisture convergence. Showers and isolated thunderstorms will once again develop near and along the ridges late afternoon as the upper-level trough crosses into western PA. Models suggest that the trough axis will be somewhat out-of-phase west of the Laurel Highlands. With the best low-level lapse rates and instability embedded in the ridges, orographic lift may help updrafts sustain some strength before quickly exiting our county warning area. Warm, dry conditions are anticipated Saturday as high pressure builds to our west.
/28/ Today and Tonight: Quiet weather is expected to continue today as the region remains under broad ridging. However, temperatures will be warm today and highs are expected to reach into the lower to mid 90s.
745 AM EDT Fri Aug 7 2020 An upper longwave trough will persist over the forecast area through today. For Saturday the trough gets pushed north and east as high pressure builds from the west and from the Atlantic. However GA remains in a weak area between the upper ridges.
Weak high pressure will rebuild into the region today for drier conditions.
/ISSUED 220 AM EDT Fri Aug 07 2020/ Areas of stratus and fog this morning followed by scattered The mid/upper level trough will continue to weaken and lift out today.
940 AM EDT Fri Aug 7 2020 A few showers and thunderstorms are possible in the vicinity of the ridges this afternoon, with mainly dry weather elsewhere. Building high pressure will create above average temperatures this weekend. Showers and isolated thunderstorms will once again develop near and along the ridges late afternoon as the upper-level trough crosses into western PA. Models suggest that the trough axis will be somewhat out-of-phase west of the Laurel Highlands. With the best low-level lapse rates and instability embedded in the ridges, orographic lift may help updrafts sustain some strength before quickly exiting our county warning area. Warm, dry conditions are anticipated Saturday as high pressure builds to our west.
Expect another breezy day across the area as we remain between a weak trough along the West Coast and high pressure to our south and east.
A weak trough axis remains to the West, providing just enough lift to generate some of the storms we are seeing. With high pressure situated over and to the east of the peninsula and with the weak trough still present, generally WSW to WNW flow remains for today. This should allow early convection near the coast to transition inland by the afternoon, concentrating the highest chances for rain over the interior later today. As high pressure remains to our east and a weak trough is overhead, light WSW flow will gradually become more WNW.
Prior to convection still expect Max Temps into the lower to middle 90s inland and upper 80s/near 90 at the Atlc Coast with peak Heat Indices/Feels Like values of 102-106. A weak trough remains draped over the region with an elongated ridge of high pressure just to our east. The highest area of thunderstorm coverage today is expected to be along the I-95 corridor and across north-central FL where PW values are forecast to be 2"+ and afternoon MLCAPE of 2000+ J/kg will be on tap. As for temperatures, highs this afternoon will be in the low-mid 90s with heat indices of 100-105.
636 AM CDT Fri Aug 7 2020 For today, an upper-level ridge centered over the Southern Plains will build eastward into the mid-Mississippi River Valley. In conjunction with this feature, low-level southerly flow will advect warmer temperatures and higher humidity into the CWA.
650 AM CDT Fri Aug 7 2020 (Today and tonight) A fairly widespread area of showers and storms has developed over north central OK early this morning along a NNW to SSE oriented warm front. Otherwise, expect breezy and hot conditions by this afternoon especially across western OK where 850 mb temps will exceed 26 C under the upper ridge.
/GG/ Prior discussion below: Today and Tonight: Quiet weather is expected to continue today as the region remains under broad ridging. However, temperatures will be warm today and highs are expected to reach into the lower to mid 90s.
316 AM MDT Fri Aug 7 2020 An all too familiar pattern of anomalous low pressure over the PacNW will keep windy and dry conditions in place today. As this trough moves farther into the interior it will be impinging on the ridge aloft which is a recognized pattern for fire weather. The closed low off the California coast isn't moving, and the ridge overhead will remain in place as well.
1000 AM EDT Fri Aug 7 2020 A weak cold front remains stalled today across the piedmont. High pressure builds in this weekend with return to typical summer weather. Better support for organized thunderstorms appears to be east of the mountains today, but as upper trough moves closer, low-mid level lapse rates should increase, with scattered to numerous coverage of showers/storms during the afternoon and evening. We will finally see the front exit the piedmont tonight and slowly experience a little bit of drier weather for Saturday, as high pressure builds in. Similar temperatures tonight as this morning, but maybe a degree or two cooler in the mountains.
Heights aloft continue to rise early this morning, as the upper ridge over the Southern Plains strengthens and begins to shift northeastward. Atop the ridge and east of a lee trough, several areas of thunderstorms are still ongoing from Oklahoma up through the Dakotas, maintained by a southerly LLJ. Heading into the afternoon, strengthening lee troughing should tighten the pressure gradient across eastern Kansas, with southerly winds increasing as a result. As this occurs, the upper ridge axis will move almost overhead, with H70 temps rising to 25-28C. Dewpoints in the low to mid 70s will push heat indices to around 105, so may need to consider a heat advisory to cover those impacts.
431 AM CDT Fri Aug 7 2020 Today and Tonight: Quiet weather is expected to continue today as the region remains under broad ridging. However, temperatures will be warm today and highs are expected to reach into the lower to mid 90s.
This is in line with the current forecast and the higher end of the guidance. A broad, flat ridge will remain over the southern U.
702 AM EDT Fri Aug 7 2020 A weak cold front remains stalled today across the piedmont. High pressure builds in this weekend with return to typical summer weather. Better support for organized thunderstorms appears to be east of the mountains today, but as upper trough moves closer, low-mid level lapse rates should increase, keeping coverage fairly numerous even in the mountains by early afternoon. We will finally see the front exit the piedmont tonight and slowly experience a little bit of drier weather for Saturday, as high pressure builds in. Similar temperatures tonight as this morning, but maybe a degree or two cooler in the mountains.
Pleasant conditions will take hold over the coming days as we remain beneath the influence of a broad upper trough over southwestern Canada. A cooler and drier airmass has filled in behind yesterdays cold front. Some areas of southern/central Oregon will even fall to near freezing by sunrise, especially the higher elevation valleys. A bit of a warmup is expected into the weekend as the airmass begins to modify and the trough axis shift slightly east into south-central Canada and the far northern Rockies region.
Later today, as a cold front moves into central North Dakota this afternoon, there will be some potential for convection along the front, as is also depicted by CAM models. First, a weak MCV did form overnight across western South Dakota along and east of a warm frontal boundary. But a better chance will likely have to wait until this afternoon and evening with an eastward moving cold front. Weather or not storms can develop further west is also uncertain, as height rises from the lifting trough into Sask/Manitoba and resulting capping may prevent much convection there this afternoon and evening.
502 AM EDT Fri Aug 7 2020 High pressure will build over the region today. Low pressure will track south of the Gulf of Maine Saturday.
The weak central GOMEX mid level trough will continue to slowly fill as the western flank of the Atlantic ridge over Florida strengthens. At the surface, the SLP and wind flow pattern over the peninsula become somewhat amorphous as the ridge overhead broadens and some slight drying occurs over south Florida, and possibly the far southern CWA.
610 AM EDT Fri Aug 7 2020 High pressure will build over the region today. Low pressure will track south of the Gulf of Maine Saturday.
As with the past few days, think convection will likely pop in the higher terrain first. /Issued 745 AM EDT Fri Aug 7 2020/ An upper longwave trough will persist over the forecast area through today. For Saturday the trough gets pushed north and east as high pressure builds from the west and from the Atlantic. However GA remains in a weak area between the upper ridges.
1017 AM EDT Fri Aug 7 2020 High pressure will build over the region today. Low pressure will track south of the Gulf of Maine Saturday.
1024 AM EDT Fri Aug 7 2020 Currently - A a ridge extends across the Florida Peninsula, resulting in light to gentle easterly breezes across the area. Lower to mid level ridging is in place aloft. Guidance suggests the lower level steering flow will back north of east this afternoon. Ridging across Florida will maintain light to gentle east breezes across Keys waters.
Temperatures will be 5-10 degrees cooler today behind last night's cold front. Highs will only reach the low to mid 80s in the valleys with 60s and 70s in the mountains.
/Tonight through Saturday Night/ Upper ridge centered over central TX continues to strengthen, effectively ending the nw flow regime we've had in place over the last few days. Remnants of this morning's convection over ern OK/wrn AR continue to infringe upon our far nrn areas, but redevelopment seems to be being squashed by the increasing subsidence in association with the ridge. Ridge to hold its place through the short term pd. This will spell much warmer temps than we've become accustomed to in August of 2020.
as afternoon high temperatures climb into the lower 80s and relative humidity values remain low. Afternoon temps should still reach into the lower 80s, which is a little warmer than yesterday. High pressure extending from New England southwestward into the Ohio River Valley will continue to dominate the weather across central Illinois today. Afternoon highs will be a couple degrees warmer than yesterday in the lower 80s. As the high slowly shifts eastward, a frontal boundary will begin approaching from the W/SW late tonight.
There is an outside chance of a thunderstorm developing, especially after 06Z as nose of the low level jet works north into areas east of I-29. With 850 hpa temperatures in the lower 20s C, should be another warm and muggy day, with highs in the upper 80s and lower 90 F. If surface temperatures are able to climb into the lower 90s, will need to keep an eye on the potential for a heat advisory.