Aikyam-Lab/Synoptic-Bench huggingface dataset:
941 AM CDT Wed Aug 14 2019 The surface cold front has moved south of the CWA and slightly cooler/drier air will filter into the Mid-South throughout the day. Surface analysis early this morning places a cold front across Central Alabama/Mississippi, then back through Northeast Texas.
Cooler weather returns for the weekend. Strong high pressure will build across the region today and Thursday resulting in sunny skies and hot weather. High pressure will weaken slightly heading into the weekend which will allow a cooling trend to develop as onshore flow strengthens.
Chattanooga Airport, TN 90 69 89 68 / 20 0 0 0 Knoxville McGhee Tyson Airport, TN 87 69 87 67 / 20 10 10 10 Oak Ridge, TN 88 69 87 66 / 20 10 10 10 Tri Cities Airport, TN 86 65 87 63 / 40 20 20 10.
High temperatures should climb into the low to middle 80s with afternoon dewpoints in the low to mid 60s. With high pressure building into the area, dry weather is expected. We should see similar, perhaps a bit warmer, temperatures on Thursday.
Ascent tied to the upper trough along with a weakening corridor of MUCAPE and low-level convergence ahead of the upper trough has focused areas of showers/isolated thunder from east-central MN into central WI. Otherwise, a cooler airmass will advect south across the area with quite a bit of stratus persisting through much of the day before some clearing develops from the north late this afternoon/evening. A quiet day is expected for Thursday as transient surface ridging works across the area.
Early this morning, a cold front/outflow boundary has pushed southwestward through the CWA, beginning to stall out across E NM and to our south across W TX.
As the day unfolds the subtropical ridge will become disorganized and recenter itself over the Four Corners region.
This axis was associated with the inverted trough which continues to sag southward over the Upper Midwest. Although this axis and trough will move southeast toward the Midwest today, there remains enough instability left over to hold/introduce isolated showers/storms this morning, and into the afternoon. Otherwise, behind this trough, 850MB temperatures drop to around 10C.
/issued 328 AM EDT Wed Aug 14 2019/ A broad mid level trough will gradually dig into the eastern US through the rest of the week, setting up a weak ridge east of Florida. At the surface, the subtropical ridge axis will continue to extend across the Florida Straits through the rest of the week, with southwesterly flow persisting. While August is typically the time of year with the highest atmospheric moisture, the air mass currently in place is incredibly moist, even by August standards. This moist air mass and southwesterly flow enhanced by the troughing aloft will favor showers and thunderstorms forming over the eastern Gulf of Mexico early each morning, then continuing to develop and shift onshore throughout the day with numerous thunderstorms and heavy rainfall.
Finally we have something to discuss besides high pressure.
511 AM EDT Wed Aug 14 2019 A trough of low pressure will bring several periods of unsettled weather to the region lasting into the weekend. High height trof through the period with models in agreement showing a stronger short wave influencing the weather on Thursday. Will keep some pops through most of the period with the highest chances on Thu. The guidance continues to show an upper level low over northern Canada remaining entrenched into the weekend.
100 PM PDT Wed Aug 14 2019 High pressure aloft will bring another hot day to the valleys and deserts Thursday.
Otherwise, it will be another cool afternoon with highs only in the lower to mid 70s. For tonight, return flow sets up as the high pressure moves east. A surface cold front will also be approaching from the northwest. When the period opens, a large broad upper level trof seems to be establishing itself over much of NOAM, including the northern tier CONUS states, with cooler than normal air remaining in place through the weekend.
332 PM CDT Wed Aug 14 2019 As of 20Z Wednesday afternoon, an expansive midlevel ridge axis was positioned across the Southwestern US -- yielding broad west- northwesterly flow across the Central and Northern Plains. At the surface, a broad ridge extended from the Northern Plains through the Central Plains with the axis bisecting SD/NE/KS. Model solutions have had run-to-run consistency with developing isolated to scattered storms as a 40 kt midlevel speed maximum overspreads the High Plains.
Timing these troughs with daytime peak heating and cloud cover, as well as available moisture will all factor into whether storms will have a chance to pop up each day.
Of concern is how the inverted trough lingers over Lake Michigan tonight and actually clips southeast Wisconsin again as it pivots away.
305 PM EDT Wed Aug 14 2019 High pressure will remain north of New England tonight. The high will retreat into the maritimes on Thursday with return flow introducing gradually more humid air to the region.
In the low levels, a ridge of high pressure encompassed the central parts of the Dakotas and NE as of midday.
Weak high pressure will affect the area on Thursday. High temperatures will be in the lower 80s.
The subtropical ridge remains centered over the Desert Southwest this afternoon with northwesterly flow aloft across the OH/TN Valleys. The surface cold front has moved south of the area with north winds up to 10 mph ushering in a drier, continental air mass. The primary change to the synoptic pattern over the next few days will be the weakening of the western ridge, transitioning to more of a quasi-zonal flow aloft across much of the CONUS. With light north to northeast winds persisting across the area through Thursday, the relatively dry air will persist, maintaining heat indices primarily in the low/mid 90s.
Cooler temperatures are in store for the next few days along with off and on small chances for showers and storms. The low clouds currently stretching along the I-65 corridor NW of Indy and in east central Indiana is expected gradually thin out by noon. A low level trough across portions of northeast Indiana interacting with a weak upper level wave will be the lifting mechanism to bring the aforementioned showers. Highs today will climb into the low to mid 80s with lower temperatures across the northeast where higher cloud cover and expected showers will keep things not as warm as further southwest.
Otherwise, expect mostly clear skies tonight with some waa/mid level accas storms possible mainly late tonight out west in advance of an approaching short wave trough. On Thursday, the ops models and high-res models all show better/more numerous storm development on Thursday afternoon into the evening with lift from a short wave trough and surface front moving in. Therefore, expect storms to develop with some being supercells/possibly severe as they move southeast with the associated upper trough and surface cold front. The storms will leave the eastern cwa Thursday night with cooler and drier north winds in behind them.
The battle between weak high pressure to the north and weak low pressure to the south will continue tonight. Pattern Synopsis/Forecast: Larger scale analysis today reveals low amplitude troughiness across the northern tier of states with ridging building off the Pacific coast toward the Gulf of Alaska. Pattern changes very little over the next few days with low amplitude troughiness continuing to dominate.
High temperatures will be a couple degrees warmer than yesterday.
/issued 941 AM CDT Wed Aug 14 2019/ The surface cold front has moved south of the CWA and slightly cooler/drier air will filter into the Mid-South throughout the day. Surface analysis early this morning places a cold front across Central Alabama/Mississippi, then back through Northeast Texas.
Later on Thursday, weak high pressure ridging returns to the area, temporarily moving precipitation away from northeast Montana.
The only area where there is even a slightest chance of any weather will be over the High Uintas where an isolated shower or thunderstorm can not be ruled out.
1120 AM EDT Wed Aug 14 2019 A trough of low pressure will interact with a wavy and nearly stationary surface frontal boundary over the state to bring several periods of unsettled weather to the region lasting into the weekend. High height trof through the period with models in agreement showing a stronger short wave influencing the weather on Thursday. Will keep some pops through most of the period with the highest chances on Thu. The guidance continues to show an upper level low over northern Canada remaining entrenched into the weekend. Areas of MVFR cigs and generally VFR vsbys will be found across the Lower Susq valley and Laurel Highlands through 17Z before become VFR over the bulk of the region.
A pleasant day in the northern Rockies today will give way to northwest flow and a weak trough descending out of Canada on Thursday. Temperatures remain on the cooler side of average through the weekend.
149 PM EDT Wed Aug 14 2019 High pressure in Ontario will slowly build toward the region through tonight.
upper level flow at 500 mb starts off zonal on Thursday night with a flat upper ridge over the southern half of the country. pattern shift in the upper flow as both the GFS/ECMWF begin to nose the ridge into the Plains from the southwest. Ridge will become further amplified going into the first half of next as upper flow becomes more southwesterly. The in-between period will be affected by the building ridge.
Chattanooga Airport, TN 90 69 89 68 / 30 0 0 0 Knoxville McGhee Tyson Airport, TN 87 69 87 67 / 40 10 10 10 Oak Ridge, TN 88 69 87 66 / 30 10 10 10 Tri Cities Airport, TN 86 65 87 63 / 40 20 20 10.
Temperatures were on the cooler side with readings as of 1 pm in the mid 60s to lower 70s. Cumulus field is expected to diminish from north to south by this evening as that trough departs to the southeast and high pressure builds in from the Northern Plains. High pressure will provide partly cloudy skies overnight with light winds. Thursday will see increasing clouds in the afternoon as high pressure slides off to the southeast and a mid-level trough approaches from the Plains.
For the rest of the short term, the area will remain in northwesterly flow and a generally troughy pattern. The extended still looks to be dry with a high pressure dominating the weather.
Deterministic models diverge some on timing of next short wave trough, with the ECMWF most consistent on moving it into eastern Dakotas later Thursday afternoon. Will bring likely PoP east into eastern MN as the upper trough moves through 06z-09z Fri.
259 PM CDT Wed Aug 14 2019 Dewpoints continue to mix out this afternoon and expect relatively pleasant overnight weather as surface ridging remains across the region.
Dry weather with cooler than normal temperatures is expected.
Storms that will form across the high plains this evening will try to make a run towards northwest Oklahoma late tonight into tomorrow morning, but at this time these storms are forecast to dissipate before reaching our area. Otherwise, indistinct waves passing through the nearly flat ridge aloft will help generate additional convection over parts of the Plains over the next several days. or warmer than seasonal.
High pressure will strengthen over Arizona today and Thursday with warming temperatures, rising to 5 to 10 degrees above normal.
241 PM CDT Wed Aug 14 2019 (Tonight and Thursday) A nearly stationary weak cold front extends across the Heartland and Concho Valley this afternoon. (Thursday Night through Next Wednesday) The aforementioned frontal boundary will begin to lift northward by Thursday night and a ridge will start building back in from the west.
So will keep the high POPs the forecast builder gave for late tonight through Thursday morning time period.
It's possible that some storms that form along the higher terrain this afternoon may reach mainly northwest Oklahoma late in the evening and overnight.
With the upper ridge drifting to the west, steering flow should bring the region of higher moisture, now over central and east Texas, south into the coastal plains on Thursday. The mid level ridge will begin to move back to the east Thursday night.
212 PM CDT Wed Aug 14 2019 The drier air mass continues to filter into the TN Valley behind the cold front this afternoon. High pressure filtering in from the Northern Plains will keep skies mostly clear and winds fairly light to calm overnight.
The fog will dissipate on Thursday morning, and another minor push of slightly cooler and drier air is expected during the day.
/Pelatti 18Z TAFS: Weak high pressure will transition into a flow from the northwest and allow for minor disturbances to pass in a northwest to southeast trajectory of approach and exit. These disturbances may cause increase in cloud cover from time to time as well as some minor chances of afternoon surface based convection up in extreme North Idaho away from TAF sites, but tomorrow morning near 15Z Thursday into the afternoon there is potential for stronger disturbances allowing for some sprinkles coupled with a bit more middle sky cover in the form of Altocumulus Castellanus clouds with the sprinkles falling out of this higher based cloud.
A weak cold front will remain nearly stationary in the vicinity of the KSJT and KBBD terminals this afternoon.
Forecast soundings from Del Rio and Austin tomorrow afternoon show an inverted V pattern in the lower levels with elevated DCAPE values near 1500 J/Kg.
The high will settle across MO overnight, leaving us with a moclear sky/diminishing winds. The highs drag down reinforcement of drier dew points leads MOS data to suggest we maintain enough of a spread overnight to preclude widespread fog development, though patches cannot be altogether ruled out.
The higher moisture ahead of this boundary will move into the region by Thursday, but VFR conditions will continue. The 12Z CRP sounding showed a slightly cooler low level thermal profile compared to yesterday.
The latest NAM and HREF guidance suggest that a complex of storms could pass over the CWA south of the Highway 2 corridor entering the area from the west by morning.
Showers and storms should increase in coverage across the lower Trans Pecos and mountain regions of West Texas through this evening. Sfc winds should veer around to the the S-SE late tonight which will hold dew points in the 60s across most of the region and contribute to warmer lows.
The drier air mass continues to filter into the TN Valley behind the cold front this afternoon. High pressure filtering in from the Northern Plains will keep skies mostly clear and winds fairly light to calm overnight.
Surface analysis shows a weak subtropical ridge axis extending from the western Atlantic through the Bahamas and the Straits of Florida into the southern Gulf of Mexico. This nearby ridge axis continues to provide light mostly southerly winds across the Keys. Aloft, light S/SW flow extends up through the lower levels, while an anticyclone over the western Gulf is providing NE flow over the Keys at mid and upper levels. Otherwise, the forecast is on track, with partly cloudy skies, gentle southeast to south winds and low temps dropping only a few more degrees into the lower 80s at most locations.
High pressure filtering in from the Northern Plains will keep skies mostly clear and winds fairly light to calm overnight.
Weak surface ridging will build into the region behind a trough axis this evening through Thursday.
714 PM EDT Wed Aug 14 2019 A trough of low pressure will interact with a wavy and nearly stationary surface frontal boundary over the state to bring several periods of unsettled weather to the region, that will last into the upcoming weekend. A few low-topped TSRA are possible across the Lower Susq Valley where sfc dewpoints are hovering around 70F and PWAT values will be running at 1-2 sigma, or about 1. Temperatures will top off very close to mid August norms which vary from the mid to upper 70s across the Northern and Western Mtns to the mid 80s in the Lower Susq Valley. The guidance continues to show an upper level low over northern Canada remaining entrenched into the weekend.
1043 PM EDT Wed Aug 14 2019 High pressure in Ontario will slowly build toward the region through tonight.
Global models indicate near zonal flow late this week into the weekend as the upper level high is suppressed into northern Mexico and the far Southern Plains.
707 PM EDT Wed Aug 14 2019 High pressure in Ontario will slowly build toward the region through tonight.
Radar and satellite trends over the last couple of hours combined with a much more stable sounding profile have prompted the lowering of rain chances across much of the area for tonight and early tomorrow morning.
There is still the low probability of -SHRA/-TSRA impacting CNM/HOB after 09z/Thur as storms possibly drift in from the far NW?. Showers and storms should increase in coverage across the lower Trans Pecos and mountain regions of West Texas through this evening. Sfc winds should veer around to the the S-SE late tonight which will hold dew points in the 60s across most of the region and contribute to warmer lows.
Ridging will stay south of Florida into the weekend.
As of 20Z Wednesday afternoon, an expansive midlevel ridge axis was positioned across the Southwestern US -- yielding broad west- northwesterly flow across the Central and Northern Plains. At the surface, a broad ridge extended from the Northern Plains through the Central Plains with the axis bisecting SD/NE/KS. Model solutions have had run-to-run consistency with developing isolated to scattered storms as a 40 kt midlevel speed maximum overspreads the High Plains.
555 PM CDT Wed Aug 14 2019 Cyclonic flow continues to bring cooler and more moist air into the region. While the clearing is taking place high pressure at the surface will shift into northwest IA late tonight. Expect lows to range from the lower 50s in northwest IA to near 60 in central SD.
Much quieter evening tonight compared to last night, and a bit cooler across the area as well. Broad upper trough aloft along with areas on the Plateau hitting convective temps did kick off a few showers during the afternoon, but models keep the area quiet overnight.
528 PM MDT Wed Aug 14 2019 Low amplitude ridging continues across the southwestern CONUS, with west/northwest flow across the northern Plains. MLCAPE of 2000 J/kg and 40kt of wind shear will result in severe storm potential, ending in the early evening as weak upper ridging begins building in.
/issued 241 PM CDT Wed Aug 14 2019/ (Tonight and Thursday) A nearly stationary weak cold front extends across the Heartland and Concho Valley this afternoon. (Thursday Night through Next Wednesday) The aforementioned frontal boundary will begin to lift northward by Thursday night and a ridge will start building back in from the west.
In the upper levels a weak trough will be over GA into the NE GOM.
/Issued 259 PM CDT Wed Aug 14 2019/ Dewpoints continue to mix out this afternoon and expect relatively pleasant overnight weather as surface ridging remains across the region.
High pressure will continue to strengthen over Arizona through Thursday with high temperatures climbing to 5 to 10 degrees above normal. High temperatures will return to near normal over the weekend as high pressure weakens.
303 PM MDT Wed Aug 14 2019 Low amplitude ridging continues across the southwestern CONUS, with west/northwest flow across the northern Plains. MLCAPE of 2000 J/kg and 40kt of wind shear will result in severe storm potential, ending in the early evening as weak upper ridging begins building in.
An upper trough will develop over the northeast Pacific over the weekend and that will probably deepen the marine layer over the weekend.
Chattanooga Airport, TN 70 90 68 90 / 0 0 0 0 Knoxville McGhee Tyson Airport, TN 69 88 67 89 / 10 0 10 0 Oak Ridge, TN 68 88 66 90 / 10 0 10 0 Tri Cities Airport, TN 66 86 63 87 / 30 10 10 10.
The coast will remain cooler, with marine stratus returning later this evening.
Cooler and drier conditions are currently present across eastern Oklahoma and western Arkansas, especially compared to the last several nights.
153 AM PDT Thu Aug 15 2019 Temperatures will top out in the 90s to around 100 in the lower valleys of northeast California and western Nevada, with 80s for Sierra valleys.
Upper high will continue to be located over the southwestern CONUS with northwesterly flow aloft over the CWA. The lift from the disturbance along with low level lift from a cold front which may push into the Oklahoma Panhandle during the afternoon may be enough to touch off some showers and thunderstorms. Have gone ahead and kept the low chances of showers and thunderstorms in the forecast for Friday and Friday night.
We are waking up a touch cooler than yesterday morning, and some patchy fog is possible through rush hour. At the mid and upper levels, Middle Tennessee remains at the base of a longwave trough that stretches across much of the northern U. High pressure will situate itself atop the TN Valley and Appalachians for the remainder of the week, keeping conditions dry.
Given the high instability and modest wind shear, there will be a slightly higher severe threat with wind and hail the main threats at this point.
This pattern will maintain a generally dry airmass which will produce little more than some daily afternoon cumulus over the higher terrain. This will bring a bit of an increase in winds across the area and cooler temperatures to northern Utah.
1257 AM EDT Thu Aug 15 2019 Aviation - Scattered showers and a few thunderstorms through the weekend - Near seasonable temperatures into Friday - More humid and warmer for the weekend The main challenge in the period deals with the risk for showers and thunderstorms over the next couple of days. The mid level trough sharpens up somewhat through the day so that may support better coverage of showers. Light rain showers will persist over central Lower through the morning hours as low pressure slowly moves east through the region.
Much of the guidance was cooler, so this should be watched. Overall we trend a degree or two warmer on Friday, but still at or below average for all locations.
/issued 241 PM CDT Wed Aug 14 2019/ (Tonight and Thursday) A nearly stationary weak cold front extends across the Heartland and Concho Valley this afternoon.
355 AM CDT Thu Aug 15 2019 The upper ridge centered over the AZ/NM border will weaken slightly as zonal flow sets up across the county by the weekend.
Otherwise, the upper-level ridge should remain firmly anchored over the southern United States, providing typical summer weather to the southern Plains region.
High pressure will continue over Arizona through Thursday with high temperatures climbing to 5 to 10 degrees above normal. High temperatures will return to near normal over the weekend as high pressure weakens.
Could be some stronger wind gusts with a few of the storms, but again, the highest severe storm chances should stay north of our area. Some model data, more notably the 00z GFS, suggests this thunderstorm complex may make it a bit farther south into the lower OH Valley during the evening and overnight.
In the low levels, a ridge of high pressure encompassed the central parts of the Dakotas and NE as of midday. The deepening cyclone will aid in the consolidation of a warm front across northeast KS. Thunderstorms are expected to develop during the afternoon and evening hours on Friday along to the north of the warm front from northeast KS into southeast NE and southwest IA, where heavy rainfall and some severe weather are possible.
Another dry and mild night with a weak upper ridge over the region. Northern areas will see clouds overnight ahead of a weak upper trough approaching the Pacific NW. Still see a minimal threat of showers Thursday across northern Valley county, otherwise tomorrow is dry and a few degrees cooler.
Some locations over Central GA(east and south of MCN) will have some of the higher heat indices that we have seen the last few days of around 105 degrees but these higher heat indices will be much more localized than widespread. upper-level ridge and western Atlantic ridge.