Aikyam-Lab/Synoptic-Bench huggingface dataset:
225 AM EDT Wed Jul 17 2019 A mid level ridge over the southeastern states will weaken and move south of the area this afternoon as a trough approaches from the west.
329 AM EDT Wed Jul 17 2019 A mid level ridge over the southeastern states will weaken and move south of the area this afternoon as a trough approaches from the west.
Slight ridging will give way to troughing over the weekend, with northwest mid/upper flow taking hold ext week as ridging builds in the western US.
A disturbance ahead of a weak low pressure trough will continue scattered showers and thunderstorms along and south of a line from KBTM to KLWT through around 03Z, then a few showers may linger there through around 06Z. The passage of the weak trough will leave the area under a brisk westerly flow aloft, which will likely bring mid and high cloudiness and cause gusty westerly winds to increase across the area after 16Z, especially along the Rocky Mountain Front and over the North Central Montana plains.
Otherwise, the Mid-South should begin to dry out as an upper ridge builds over the area.
359 AM CDT Wed Jul 17 2019 Water vapor loop indicated an upper level trough over nw MT/ID/NV. Warm advection precip to occur today east of upper trough.
A typical summertime pattern continues overnight and into tomorrow as an upper-level ridge remains in place across the Southern Plains, which should keep things generally dry.
The region will be between high pressure to the east southeast and a trough of low pressure to the north northwest through Tonight. The low level flow will help keep the east coast sea breeze pinned near the coast, likely not making it much past I95.
Thursday Night Through Wednesday Upper level ridge of high pressure will be building across the area during the first half of the extended term, while at the surface a warm and moist flow of air will continue to move across the area from the Gulf.
High pressure will then begin to bounce back toward the Four Corners, with a gradual return of moisture.
A mid level ridge across Texas and Oklahoma will build into the region beginning today, however weak energy moving through the periphery of the ridge will initiate some precip chances across portions of the area today before the ridge fully builds in. A few of the high res models show more of a cluster or line of storms moving into the area from the north during the afternoon, not as confident in this scenario however confidence is high that at least isolated to scattered storms will occur mainly east of US Highway 65 and especially closer to US highway 63. However most locations will still reach the low to mid 90s with heat indicies ranging from 100-108. It will also be a very mild night with lows ranging from the lower to upper 70s from east to west.
Didn't adjust temperatures a great deal across the area, but followed some of the higher resolution guidance for dewpoint temperatures. In addition to this, it kept the higher dewpoints in central Nebraska and along and east of 281. The combination of the low to mid-70 dew points and the temperatures give most locations heat index values over 105 and some along the Highway 81 corridor approaching 110.
/issued 351 AM CDT Wed Jul 17 2019/ Upper ridging continues over the southern half of the country. Good low-level moisture will be present with storms expected to develop this afternoon across the higher terrain west of the Pecos River and possibly spread as far east as the western Permian Basin.
The west coast upper level low pressure trough continues to provide cooler conditions in central CA, with some ocean cooled influence in the SJ Valley as the marine layer has risen to around 2500 ft and moderate onshore surface pressure gradients persist. Highs across the area yesterday topped out mostly a couple of degrees below normal and should be similar today under the influence of the low pressure trough. The trough is progged to lift to the north through Thursday and highs Thursday are expected to rise just slightly to right around climo.
Thunderstorms are possible Wednesday afternoon and evening in association with a short wave trof.
As this low pushes farther north and east today, thunderstorms will regenerate across eastern SD and west central MN. LLM is abundant ahead of the low.
Maliawco Previous Discussion: Weak cyclonic flow remains over the region through the weekend maintaining the slightly cooler conditions.
An upper level high pressure system is expected to persist over the SRN 1/2 of the CONUS during the period, per deterministic output. Anticipate no significant precipitation during the period owing to the upper ridge and insufficient moisture.
403 AM CDT Wed Jul 17 2019 Global models agree in bringing a short wave trough through the h500 ridge axis today, flattening it and dragging a cold front east through the region today into tonight. Short term (CAM) model guidance is not in really good agreement other than to suggest scattered convection in the vicinity and behind the cold front as it moves through this afternoon and evening. So we continue to expect an active weather pattern with several cold frontal passages this week bringing showers and scattered thunderstorms through the region later this week into the weekend.
Not much change in the overall pattern as a weak trough lingers along the West Coast into the weekend.
925 AM EDT Wed Jul 17 2019 The mid level ridge remains near the FL-GA border with low level south to southeast flow around the low level Atlantic ridge. Another hot afternoon is in store with highs in the lower 90s coastal to mid 90s across the interior.
The scattered showers/thunderstorms will continue across the area into the evening with another round of convection expected tonight as what's left of Barry moves out and a trough axis swings in. Chattanooga Airport, TN 87 74 91 75 / 70 40 40 20 Knoxville McGhee Tyson Airport, TN 86 72 90 72 / 70 50 40 30 Oak Ridge, TN 85 72 90 73 / 70 50 40 20 Tri Cities Airport, TN 85 69 89 69 / 70 60 50 20.
High pressure ridge has weakened slightly and shifted westward over the FL Panhandle with axis still across SE GA/NE FL. This combined with humidity and dew points in the lower/middle 70s will have peak heat indices in the 104-108F range by early this afternoon area-wide. 1 inches, and Hi-Res models are fairly aggressive with storm chances this afternoon along the East Coast Sea Breeze as it develop along the coast then Northeast flow aloft around the High Pressure will slowly push storms inland where multiple storm mergers/outflows come together for scattered to numerous coverage area-wide, starting with 30-50% along the coast increasing to 50-70% coverage over inland areas. Southerly flow will continue with ridge axis across the waters.
436 AM MDT Wed Jul 17 2019 Weak cyclonic flow remains over the region through the weekend maintaining the slightly cooler conditions.
/15/ Today through tonight: The upper trough and the remnant moisture from Barry will shift east on Wednesday, with the best chance of showers/storms over the northeast. Another very humid day is on tap with highs in the low 90s. The potential for storms will diminish by early evening, with overnight lows falling into the low/mid 70s.
Global models agree in bringing a short wave trough through the h500 ridge axis today, flattening it and dragging a cold front east through the region today into tonight. Short term (CAM) model guidance is not in really good agreement other than to suggest scattered convection in the vicinity and behind the cold front as it moves through this afternoon and evening. So we continue to expect an active weather pattern with several cold frontal passages this week bringing showers and scattered thunderstorms through the region later this week into the weekend.
Global models agree in bringing a short wave trough through the h500 ridge axis today, flattening it and dragging a cold front east through the region today into tonight. Short term (CAM) model guidance is not in really good agreement other than to suggest scattered convection in the vicinity and behind the cold front as it moves through this afternoon and evening. So we continue to expect an active weather pattern with several cold frontal passages this week bringing showers and scattered thunderstorms through the region later this week into the weekend. Cold front across eastern Montana will move east today and will be the focus for scattered showers and thunderstorms this afternoon and evening.
High pressure remains over the area producing pleasant boating conditions over the coastal waters.
Water vapor loop indicated an upper level trough over nw MT/ID/NV. Warm advection precip to occur today east of upper trough.
Global models agree in bringing a short wave trough through the h500 ridge axis today, flattening it and dragging a cold front east through the region today into tonight. Short term (CAM) model guidance is not in really good agreement other than to suggest scattered convection in the vicinity and behind the cold front as it moves through this afternoon and evening. So we continue to expect an active weather pattern with several cold frontal passages this week bringing showers and scattered thunderstorms through the region later this week into the weekend. A weak cold front across eastern Montana will move east today and will be the focus for scattered showers and thunderstorms today and tonight.
Morning surface and upper air analysis show the ridge of high pressure spread across Texas and much of the Gulf Coast. At the same time the downward subsidence from the upper ridge will keep a kibosh on any precipitation keeping South Central Texas dry. With the high dewpoints and the afternoon temperatures warming into the mid to upper 90s heat index values will also climb each afternoon. This trend puts temperatures a degree or two warmer than normal in the afternoons, and right around seasonal normals at night.
Water vapor imagery showing upper low moving into BC with strong westerly flow aloft into the Pacific northwest. Cloud cover and cooler airmass will keep highs in the 70s to lower 80s. Weak upper level low pressure will result in mid deck clouds for DLS/YKM/PSC/PDT/ALW through this evening, thinning out overnight.
As convection translates across the state, effective bulk shear quickly decreases in our CWA as the low level jet max edges towards far eastern Kansas after midnight.
The HRRR has done the best so far at limiting the cloud and storm potential after 15Z, while other CAM solutions have shown more clouds and convection stalling temperatures in the low 80s.
A forecast update is in place for cooler temperatures this afternoon across ncntl Nebraska north of Broken Bow. The RAP model holds this warm air over swrn Nebraska tonight with cooler air aloft across scntl Nebraska where clusters of weakly sheared heavy thunderstorms will probably form, perhaps affecting Frontier and Custer counties for a few hours late this afternoon and this evening. Outflow from the storms across SD last night have pushed a weak cold front into wrn and ncntl Nebraska. Temperatures in the low 100s will likely develop behind the dryline Thursday afternoon. The temperature forecast uses a blend of the warmer NAM/ECM guidance and the dew point forecast leans on the sharper NAM guidance which pushes dew points into the lower 70s across ncntl Nebraska Thursday afternoon.
Latest heat index values range from the low to mid 90s across southeast Oklahoma and northwest Arkansas with values above 100F across northeast Oklahoma through west central Arkansas.
Storms will become more focused and organized during the late afternoon and evening hours along a cold front that will drop south out of the Great Lakes. Slight drier and cooler air plus NW flow behind the front will end precip chances, with the front moving through the entire area by Thursday morning. Brief NW flow behind the cold front and exiting Barry remnants Thursday morning will quickly becoming a building ridge by the afternoon. Building pressure heights will allow for hotter high temperature Thursday despite the cold frontal passage, with most areas above normal. Residual moisture along the eastern ridges into the WV mountains plus daytime heating may allow for a few afternoon thunderstorms.
Given the limited coverage, expect temps to return to the low 90s across most of our area.
At the start of the period, a broad upper ridge spans across the CONUS, with high pressure centered over the southeastern part of the country.
5 degrees C which may support some ACCAS development but confidence in this development is also a bit on the lower side. The least hot readings will likely be across southwest MN where the low levels take the longest to recover.
Shower and thunderstorm development has struggled this afternoon in large part because of the upper ridge building over the area. Best chances for showers and thunderstorms will be south of I-40 though coverage will be limited with upper level high pressure over the region.
This is in response to a upper trough axis sliding in.
High pressure persists over the area with PWATs remaining below normal through Thursday night, therefore, no significant precipitation is expected through the period.
305 PM CDT Wed Jul 17 2019 Large scale flow consisting of a broad trough stretching across the Pacific NW/Northern Plains. To the south, a high pressure dome was in control over the southern half of the CONUS. South of the boundary dew point temperatures were in the low/mid 70s with current heat indices for the most part over 100F, and will continue to increase through the rest of this afternoon.
With 500mb temps slightly cooler around -7C, slightly higher DCAPE values and high Precip Water values should support strong to isolated severe downbursts from taller storm cores that develop through early evening. High temperatures will be in the lower-mid 90s inland. Weak break in upper ridge will exist over forecast area this period.
The RAP model holds this warm air over swrn Nebraska tonight with cooler air aloft across scntl Nebraska where clusters of weakly sheared heavy thunderstorms will probably form, perhaps affecting Frontier and Custer counties for a few hours late this afternoon and this evening. Outflow from the storms across SD last night have pushed a weak cold front into wrn and ncntl Nebraska. Temperatures in the low 100s will likely develop behind the dryline Thursday afternoon. The temperature forecast uses a blend of the warmer NAM/ECM guidance and the dew point forecast leans on the sharper NAM guidance which pushes dew points into the lower 70s across ncntl Nebraska Thursday afternoon.
Speaking of temps, wouldn't be surprised if Heat Index values creep into the low 100s tomorrow. As of 17Z, most of the showers/storms with a trough and remnants of tropical system Barry were east of our area.
207 PM CDT Wed Jul 17 2019 (Tonight and Thursday) So far today, it is not as hot as it was at this time yesterday, likely due to a little increased cloud cover and a weaker 850 mb thermal ridge. The subsidence from the upper ridge will very likely suppress any shower/storm activity today and Thursday. Tonight and Thursday, temperatures will be pretty similar to today/this morning, except perhaps 1-2 degrees lower due to very slight weakening in the upper ridge and 850 mb thermal ridge.
A mid level thermal ridge will remain anchored near the region so continued above normal high temperatures can be expected through the weekend.
Speaking of temps, wouldn't be surprised if Heat Index values creep into the low 100s tomorrow. Scattered RA and TS are possible through the day, with the highest chances to linger over CSV into the evening.
Through the morning and afternoon, surface dewpoints are expected to decrease as low-level moisture as mixes through the deepening the PBL; however, given the pace of the surge, sufficient moisture may work its way into the lower Colorado River Valley and southern Mohave County resulting increased clouds and possibly a few thunderstorms.
/28/ Prior discussion below: Today through tonight: The upper trough and the remnant moisture from Barry will shift east on Wednesday, with the best chance of showers/storms over the northeast. Another very humid day is on tap with highs in the low 90s. The potential for storms will diminish by early evening, with overnight lows falling into the low/mid 70s.
244 PM CDT Wed Jul 17 2019 The area remains under a weak flow regime today with a weakness in broad upper-level ridging that extends across the Desert Southwest and the MS Valley. The mid-level moist axis shifts west Thursday with the upper high building over the ARKLATEX region.
Will need to wait for the main upper trough to move across the Dakotas overnight to initiate convection.
245 PM EDT Wed Jul 17 2019 The upper ridge remains in place over the southeast U.
High temperatures will rise to the upper 80s and lower 90s, allowing humidity values to fall below 20 percent for most of the lower elevations, with areas across Sweetwater County near 10 percent.
As a result, hourly temperatures have been running a solid 5 degrees cooler than expected in many places. Tomorrow is expected to be warm once again, and, in theory, there shouldn't be much convective debris to keep us cooler like what happened today.
There is ample moisture in the low levels for low ceilings and BR at CSV.
Just about the entire area is running around 5 to 10 degrees warmer than yesterday, thanks to building high pressure aloft and the sunnier skies at the coast. That said, northerly breezes are noticeably stronger along much of the coast and across some of the near-coastal hills and mountain ridges. These winds will remain through the end of the week, at least during the afternoon and evening hours, and will keep areas by the cold Pacific Ocean waters feeling cooler.
/Tonight through Thursday Night/ Isolated convection associated with the sea breeze is moving northward into portions of Deep East Texas and may also affect the Lower Toledo Bend Reservoir through early this evening before dissipating with the loss of diurnal instability. An upper level ridge is currently over the Southern Plains and will gradually move into the Southeast CONUS while strengthening. Subsidence from the deep ridging will continue to promote warm and generally dry conditions. With the center of the upper ridge passing overhead, vertical mixing should be enough to bring drier air from aloft down to the surface.
A weak cold front will move onshore this evening with some light rain possible mainly on the coast from Coos Bay north and across the Umpqua basin.
/issued 244 PM CDT Wed Jul 17 2019/ The area remains under a weak flow regime today with a weakness in broad upper-level ridging that extends across the Desert Southwest and the MS Valley. The mid-level moist axis shifts west Thursday with the upper high building over the ARKLATEX region.
622 PM CDT Wed Jul 17 2019 Large scale flow consisting of a broad trough stretching across the Pacific NW/Northern Plains. To the south, a high pressure dome was in control over the southern half of the CONUS. South of the boundary dew point temperatures were in the low/mid 70s with current heat indices for the most part over 100F, and will continue to increase through the rest of this afternoon.
This trough is potentially stronger. Regarding temps: Near seasonal values (lows in lower 60s/highs in the low to mid 80s).
406 PM CDT Wed Jul 17 2019 Weather currently dictated by fringe flow around Bermuda ridge extension across the eastern Gulf of Mexico and building westward.
High pressure aloft will strengthen across the region beginning during the latter half of the weekend.
/issued 207 PM CDT Wed Jul 17 2019/ (Tonight and Thursday) So far today, it is not as hot as it was at this time yesterday, likely due to a little increased cloud cover and a weaker 850 mb thermal ridge. The subsidence from the upper ridge will very likely suppress any shower/storm activity today and Thursday. Tonight and Thursday, temperatures will be pretty similar to today/this morning, except perhaps 1-2 degrees lower due to very slight weakening in the upper ridge and 850 mb thermal ridge.
The low level moisture surge out of the Gulf of California has been sheared eastward into central Arizona, limiting any chance of convection across southern Mohave County. As discussed this morning, the weak troughing aloft has resulted in persistent dry, southwesterly flow aloft and breezy winds over the area this afternoon.
806 PM EDT Wed Jul 17 2019 The latest RAP model has mid level ridging continuing along the Gulf coast and most of FL overnight - while an axis of high pressure from the Atlantic stretches through central FL to the Gulf of Mexico.
The Keys lie within gentle to moderate ESE low level flow to the south of this ridge axis. Otherwise, expect mostly clear to partly cloudy skies and gentle ESE breezes, with lows dropping only a couple more degrees into the lower 80s by morning.
High pressure aloft will strengthen across the region beginning during the latter half of the weekend. The forecast area is under zonal flow aloft this evening between high pressure centered over the south central United States and a broad Pacific Northwest trough.
Cam models agree in dry weather most of the day after the cold frontal passage. The extended will begin with cooler temperatures as the flow aloft remains slightly cyclonic with a significant upper low in central Canada extending into the northern plains.
Currently have painted the highest precipitation chances in NE Tennessee/SW Virginia where storms are moving in from SE Kentucky. This is also the areas that have seen some of the higher precipitation totals over the past 24 hours. Expect coverage to isolated/scattered, with the highest chances being along the higher terrain or along any outflows left by this mornings storms. Temperatures are expected to be a few degrees warmer today as a bit more sun shines through, and should be right around normal for this time of year.
On Friday, West Texas will be squeezed between two upper level ridges: one over the southwestern US and another over the southeastern US.
Tonight Through Friday An upper ridge will be the main feature in the short term.
333 AM CDT Thu Jul 18 2019 Upper ridging continues over the region today with hot temperatures.
Went on the warmer side of guidance for lows tonight given another mixy overnight period, though lesser cloud cover should support slightly cooler conditions. Friday again appears to be another obvious day of extreme heat with the only notable change in the setup being slightly rising heights as the center of the broad upper high meanders east- northeast into the mid-Mississippi Valley.
Overall not much change in airmass today compared to yesterday with expected temps in the mid-upper 90s and dew points in the low-mid 70s yielding heat index values between 105-112 over much of the area.
The hot and humid conditions will prevail through the weekend as an upper ridge remains located over the region. The ridge will begin to retrograde back to the west by the latter part of the weekend.
351 AM CDT Thu Jul 18 2019 High pressure continues to dominate the southern CONUS and hot to very hot temperatures are expected.
1032 PM PDT Wed Jul 17 2019 A cold front passage tonight will bring widespread breezy to windy conditions tonight and Thursday.
Upper level high pressure will remain overhead through Fri.
Overview: GFS/ECMWF long range guidance suggest that the Tri- State area will be situated on the eastern periphery of an amplifying upper level ridge over the Rockies, in light N-NNW flow aloft.
The storms may be able to reach farther south into Indiana and bring rain and momentarily cooler temperatures.
The lower tropospheric thermal fields will be just slightly hotter today, and given a slightly warmer start this morning, we will likely see many areas exceed 102 degrees for highs with a few locations as high as 105 degrees, especially up around Hays, where most of the models suggest the lower tropospheric thermal ridge will be nosing into.
This airmass will compete with the drier westerlies over the Great Basin and northern Arizona for a few days, before a reorientation of the ridge allows this moisture to move fully north and west into Arizona over the weekend.