Aikyam-Lab/Synoptic-Bench huggingface dataset:
626 AM EDT Sun Aug 11 2019 Upper air pattern consists of 500 mb troughs on both coasts with a ridge across the plains. The ridge flattens out this forecast period as the trough on the west coast moves into it and the upper flow becomes more zonal. A weak cold front will move through the area today and will have some 850-500 mb q-vector convergence and a narrow band of deeper moisture with it.
The upper level high pressure system will remain over the region during the period (deterministic NWP output/persistence.
500 mb high pressure in control of the region will not only produce the heat but also dry weather for the short term forecast period.
Temperatures today look seasonable, and perhaps a bit on the cooler than normal side with highs mainly in the 80s for nearly all of the CWA. Confidence is not the highest with placement, but this can be adjusted if needed by the day shift. Ensembles indicate a general amplification of the upper ridge in the west and troughing developing in the eastern United States toward late work week, but the western ridge may be broken down as another trough moves in from the northwestern United States.
Updated at 206 AM EDT Sun Aug 11 2019 High pressure from the upper Ohio Valley to the mid Atlantic with generally low RH in the column will lead to dry and pleasant summer weather today.
Tolerable dew points dipping to the low to mid 60s will result in max heat index values in the mid to upper 90s.
An ejecting s/wv trough in eastern Arizona will continue to bring showers and thunderstorms to southern and central Apache county for most of today. Much drier air at the surface and mid-levels will continue to push slowly east across the remainder of Arizona, thanks to a deep low moving trough the northern Great Basin. However, another Great Basin trough lurking out at the end of the forecast period may put an end to any return moisture flow, if it trends any farther south.
Over time, as an upper level low pressure system tracks through the region, expect showers to become more numerous along with a chance of thunder.
/issued 248 AM CDT Sun Aug 11 2019/ The heat continues for at least a few more days as high pressure sits along the Red River.
1010 AM EDT Sun Aug 11 2019 Aviation sections updated High pressure over eastern OH/western PA will move off to the east and bring warmer, gradually more humid air into the area today and tonight. A warm front from the middle MO Valley southward into AR will slow slowly move eastward across IA/MO/IL tonight and effect our weather on Monday and Monday night. Surface analysis shows high pressure in place across eastern Ohio.
This is due to an upper level low currently over central Oregon that is beginning to move north and east.
Southwesterly flow aloft will allow for subtle perturbations in the upper flow to track northeast into the forecast area out ahead of the main upper trough.
A slight weakness in the upper ridge may allow for a modest increase in cloud cover and shower activity this afternoon, but mainly over the Atchafalaya Basin once again, and into Central LA too. Continued hot with afternoon max heat indexes of 105-109 and minimal rain chances in the lower Atchafalaya.
Will be monitoring to see how far south these develop with a few differences in placement still among the high resolution models. Temperatures will definitely feel quite a bit cooler today than what we have previously experienced with most valley locations staying in the mid 70's.
1215 PM PDT Sun Aug 11 2019 Temperatures will get hot the next few days across central California as high pressure builds over the region.
Low pressure will essentially split on Monday with most of the energy either over ND where an upper low will also move through, or across IA.
256 PM EDT Sun Aug 11 2019 Upper air pattern consists of 500 mb troughs on both coasts with a ridge across the plains. The ridge flattens out this forecast period as the trough on the west coast moves into it and the upper flow becomes more zonal. A weak cold front will move through the area today and will have some 850-500 mb q-vector convergence and a narrow band of deeper moisture with it.
159 PM CDT Sun Aug 11 2019 Upper ridge centered over N TX today will continue to dominate the wx pattern for a large portion of the country.
24hour trends show most areas slightly warmer which is also handled with current forecast.
233 PM CDT Sun Aug 11 2019 (Tonight through Monday) Hot and dry conditions persist under a strong upper ridge.
110 PM EDT Sun Aug 11 2019 Upper air pattern consists of 500 mb troughs on both coasts with a ridge across the plains. The ridge flattens out this forecast period as the trough on the west coast moves into it and the upper flow becomes more zonal. A weak cold front will move through the area today and will have some 850-500 mb q-vector convergence and a narrow band of deeper moisture with it.
116 PM EDT Sun Aug 11 2019 Today will be mostly sunny and comfortable once again as high pressure departs.
Temperatures be cooler today with highs only topping out in the mid 60s and 70s. KOTX morning sounding suggests precipitable water content is still on the high side coming in at just under an inch which is close to 170 percent of normal. The positioning of the slow moving and eventual exiting upper level low keeps a conditionally unstable airmass in place overhead as such convection in the form of thunderstorms and showers. /Pelatti 12Z TAFS: Upper level low pressure system will pass over the region today with the center of circulation noticeable on satellite moving over eastern OR at 12Z.
Meanwhile, the Atlantic basin remains quiet with NHC expecting no tropical cyclone development for the next 5 days. A subtropical ridge axis is still aligned east-west through the Straits of Florida this afternoon.
Cold Front Moving Through Tonight. Upper low near Hudson Bay with troughing down into the Great Lakes. Surface cold front extends from near Hudson Bay down through Lake Superior and into S Minnesota. The upper low will track east pushing the cold front through northern Michigan overnight. Not much precipitation along the cold front attm upstream.
Temperatures be cooler today with highs only topping out in the mid 60s and 70s. KOTX morning sounding suggests precipitable water content is still on the high side coming in at just under an inch which is close to 170 percent of normal. The positioning of the slow moving and eventual exiting upper level low keeps a conditionally unstable airmass in place overhead as such convection in the form of thunderstorms and showers. /Pelatti 18Z TAFS: Upper level low pressure system to track rather slowly over the aviation area today allowing for thunderstorms and showers to linger for a spell.
240 PM CDT Sun Aug 11 2019 Our dirty ridge continues to circulate over most of TX this afternoon, allowing monsoonal moisture to sweep into NM and parts of West Texas. A weak troughing feature has been lifting across NM today, which is currently providing lift for storms over the high terrain of NM and the TX/NM border. All the while, an upper level low at H3 has been slowly circulating north from the Big Bend into the Trans-Pecos. Oh, but there's "relief" ahead! This little trough producing storms today will slip by to the north late Monday pulling a "cold" front through behind it.
A dry cold front will move through the northern half of the forecast area today. Building high pressure will result in a warming trend for the middle part of the week. An upper trough is centered over southwest Idaho this morning and the associated front is near a KENV-KLGU line as it tracks southeast. Southwest flow ahead of the trough has drawn much drier air into the western two-thirds of Utah, with satellite derived PWs in the 0. The front is progged to makes its way through the northern half of the forecast area through the remainder of the morning before stalling and dissipating as the associated trough grazes far northern Utah. Maxes will also be noticeably cooler behind the front, up to 5F below values observed yesterday for portions of northern Utah.
123 PM CDT Sun Aug 11 2019 For the 11/18Z TAF period, dominant upper level ridge will keep VFR conditions prevailing aside from some brief patchy morning fog at a few sites. A few triple digit readings are certainly possible this afternoon, but most areas will top out in the mid to upper 90s as the center of the upper level ridge axis inches ever closer to heart of the Ark-La-Tex.
High pressure and warm temperature/heat index is the main story for the next 24 hours.
Upper level ridge remains entrenched over Texas with 595dm heights. We might see the ridge move back to the west over the southern Rockies mid week. Overpeck With a continued strong upper-level ridge over the area, conditions through the TAF period will be very similar to those seen over the past few days.
1221 PM EDT Sun Aug 11 2019 Today will be mostly sunny and comfortable once again as high pressure departs.
With the Keys lying just north of the ridge axis, light southwest surface winds currently prevail. Could also be some extra jet stream lift this afternoon due to a jet streak rounding the southeast periphery of the large upper high centered over Texas. When all things are considered, the bottom line for today is that near-climo 30-40 PoPs continue to look good over the Lower/Middle Keys, with 50 PoPs for the Upper Keys.
WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO The low clouds of the marine layer showed the coastal areas and westernmost valleys some love this morning, but are just not into the Inland Empire. Our summer doldrum pattern continues with a trough of low pressure to the north and a ridge of high pressure to the east. Today we transition from the trough dominated environment and the ridge takes a turn at influencing SoCal for a few days.
220 PM MDT Sun Aug 11 2019 Unstable conditions are in place with a strong upper low moving through western Montana this afternoon. The dynamics with the upper low will sustain decent rainfall overnight over the NE zones then rainshowers gradually decrease over the northern zones Monday as the upper low lifts up into Canada.
228 PM EDT Sun Aug 11 2019 High pressure in control through Monday.
Strong upper ridge aloft will be stationary over southern Plains and Gulf Coast states during this period. Latest guidance suggests slightly lower high temperatures each day eastern counties, though still quite hot interior areas with upper ridge over the area. As we've seen throughout the warm season, upper pattern reverts back to western ridge/eastern trough during this period, though by the weekend, upper trough shifts off east coast as upper ridge expands eastward across central U. High pressure will remain well east of the waters, with low pressure to the west, maintaining a daily southerly flow across the waters, with more southeasterly flow each afternoon nearshore with sea breeze.
259 PM CDT Sun Aug 11 2019 Main challenge is slight adjustment to heat advisory headline for Monday and late day precip/convective chances along the weak cold front thru Monday night.
The high pressure ridge will remain centered over Texas and dominate the weather for the South Central Plains through Monday. While temps continue to run above normal they should remain 1-3 degrees below record highs, and 1-2 degrees cooler than the record high minimums.
248 PM MDT Sun Aug 11 2019 The upper ridge is moving off to the east this afternoon as an upper trough approaches from the west with southwesterly flow aloft over the forecast area this afternoon. At the surface, low pressure has developed over north central Wyoming with a frontal boundary extending northeastward into the far northwestern corner of South Dakota. Areas of low stratus though the morning have kept temperatures relatively cool so far but temperatures have risen to around 80 degrees in the areas where the low clouds have since dissipated. Shear profiles and the low LCL remain favorable for supercells as well as a tornado threat. A broad ridge will gradually build across the Rockies and Plains behind exiting system. Isolated storms will still be possible at times as an occasional weak disturbance crosses ridge.
Overall no real aviation concerns going the next 24 to 36 hours under upper level ridging. Upper level ridge remains entrenched over Texas with 595dm heights. We might see the ridge move back to the west over the southern Rockies mid week.
A high pressure system remains centered over northeastern Texas with a ridge extending into the western Dakotas with a low pressure upstream across the pacific northwest.
Temperatures were generally in the mid-upper 80s with the typical urban heat island areas warming into the lower 90s. Lows are expected to drop into the mid-upper 60s, though the urban heat islands will likely remain in the lower 70s. So afternoon heat indices will likely be in the lower-mid 90s.
Very hot temperatures will continue into tomorrow as the ~596 dam mid-level ridge remains centered across the Arklatex. The attendant low-level thermal ridge will remain in place once again tomorrow afternoon with progged 850 temperatures ~24 to 30 C. High temperatures will be in the low 100s F with heat indicies from 105-110+ F. The synoptic pattern will begin to change late Monday as a mid- level trough across the southwest U. Mid-level height falls will move center of the mid-level ridge to the southwest.
- Ridge may break down enough for a boundary to push into the area midweek to lower max temps a couple of degrees. Upper level ridge will still be parked over Texas and limit convection. 0 inches of PWAT over the area but subsidence from the ridge is just too much for convergence on the sea breeze to over come. 0 inches of PWAT tomorrow as well but again think the ridge will be just too much to need any rain chances in the forecast.
/issued 240 PM CDT Sun Aug 11 2019/ Our dirty ridge continues to circulate over most of TX this afternoon, allowing monsoonal moisture to sweep into NM and parts of West Texas. A weak troughing feature has been lifting across NM today, which is currently providing lift for storms over the high terrain of NM and the TX/NM border. All the while, an upper level low at H3 has been slowly circulating north from the Big Bend into the Trans-Pecos. Oh, but there's "relief" ahead! This little trough producing storms today will slip by to the north late Monday pulling a "cold" front through behind it.
The trough currently over the Pacific Northwest continues to slide to the northeast dragging dry air through the Great Basin this afternoon. This gradient is evident in surface observations as well with RHs at locations in the dry air in the low 20's to mid-teens. Afternoon showers and storms remain a possibility with residual moisture in the higher elevations.
NVA behind a departing trough along with a low level high pressure center moving over the area tomorrow will dry things out. The only chance for showers and storms will be over the high country mainly south of I-70 and the Palmer Divide. Northwesterly winds will increase during the late morning with sustained winds between 10-20 mph, highest across the Cheyenne Ridge.
/Tonight/ Even with the cu field having diminished with the setting sun, temps have only fallen slowly and still remain in the mid and upper 80s as of 0230Z, which are 0-2 degrees warmer than what was observed 24 hrs ago. A mostly clear sky should persist overnight, with the center of the H500 ridge expected to drift E into SW AR/N LA by daybreak Monday.
Cooler weather returns for the end of the week. Today has been warmer and drier as high pressure ridging builds over the area. Temperatures at 2 pm were generally about 3 degrees warmer than the same time yesterday. Over the northern Sacramento Valley it was about 10 degrees warmer, due to a change from clouds and scattered thunderstorms to sunny skies today. The rest of the Valley should see above normal lows in the low to mid 60s, mountains in the 40s and 50s. As the Four Corners ridge begins to expand westward, temperatures will rise this week, above average Monday and continuing to increase through mid-week.
Chattanooga Airport, TN 72 94 75 97 / 0 10 10 20 Knoxville McGhee Tyson Airport, TN 70 93 74 94 / 0 10 10 20 Oak Ridge, TN 70 93 73 94 / 0 10 10 20 Tri Cities Airport, TN 65 90 69 91 / 0 10 10 40.
/issued 233 PM CDT Sun Aug 11 2019/ (Tonight through Monday) Hot and dry conditions persist under a strong upper ridge.
644 PM CDT Sun Aug 11 2019 Main challenge is slight adjustment to heat advisory headline for Monday and late day precip/convective chances along the weak cold front thru Monday night.
A dry cold front over northern Utah will dissipate this evening. Building high pressure will result in a warming trend for the middle part of the week.
A strong late-season upper low and trough is situated over northern Idaho and western Montana this afternoon.
The upper ridge is moving off to the east this afternoon as an upper trough approaches from the west with southwesterly flow aloft over the forecast area this afternoon. At the surface, low pressure has developed over north central Wyoming with a frontal boundary extending northeastward into the far northwestern corner of South Dakota. Areas of low stratus though the morning have kept temperatures relatively cool so far but temperatures have risen to around 80 degrees in the areas where the low clouds have since dissipated. Shear profiles and the low LCL remain favorable for supercells as well as a tornado threat. A broad ridge will gradually build across the Rockies and Plains behind exiting system. Isolated storms will still be possible at times as an occasional weak disturbance crosses ridge.
Zonal flow aloft has setup over the area in the wake of the departing upper level trough. Late in the week upper level troughing will move over the region yet again.
Another Hot and Humid day expected on Monday with more onshore easterly flow to keep Max Temps down just a bit in the lower to middle 90s, but high humidity will continue Heat Indices peaking in the 105-110 range and Heat Advisory may be required for some locations.
Mostly dry zonal flow aloft will develop over Western Washington tonight as a broad upper trough over Eastern Washington exits to the northeast.
Gilstad A strong late-season upper low and trough is situated over northern Idaho and western Montana this afternoon.
Return flow will continue overnight, before veering to west Monday in response to leeside troughing on the Front Range. /issued 159 PM CDT Sun Aug 11 2019/ Upper ridge centered over N TX today will continue to dominate the wx pattern for a large portion of the country.
The subtropical low pressure circulation responsible for the present active thunderstorm scenario will be quickly moving east of the Continental Divide tonight, leaving a great deal of moisture across the region.
507 PM EDT Sun Aug 11 2019 High pressure in control through Monday.
Temperatures and humidity will trend higher early in the upcoming week ahead of a wave of low pressure that will move through on Tuesday. High clouds are skirting far western PA as outflow from a midwestern MCS spirals SE on the eastern periphery of the subtropical ridge. Overnight humidity will be on the comfortable side, thanks to surface dewpoints in the low to mid 50s. An uptick in temperatures and dewpoints/humidity will be noticeable by Monday afternoon as low level flow turns south/southwesterly ahead of an approaching cold front. A frontal system and low pressure center will spread increasing clouds and POPs for Tuesday. However, latest GFS has trended a little further south which could leave northcentral PA on the cool side of the warm front.
Weak high pressure builds across the interior Pacific Northwest early this week, keeping dry conditions and warming temperatures back up to near or just above normal.
A weak upper level trough will exit the region tonight.
/issued 159 PM CDT Sun Aug 11 2019/ Upper ridge centered over N TX today will continue to dominate the wx pattern for a large portion of the country.
The mid-level thermal ridge will remain anchored over the region through Tuesday with 850mb temperatures in the 30-32C range. Cooler in the mountains and highs nearing 110F along the Rio Grande. A cold front will enter the region Tuesday but won't offer many places any relief.
It should also bring much cooler air and gusty winds through the day that have raised the lake wind advisory for the afternoon. Tuesday to Tuesday night: Partial clearing is expected as high pressure works its way into the surface from the northwest and keeps things dry. Expect cooler than average temperatures.
Surprise, surprise, another day of abnormally high temperatures continues today as the stubborn sub-tropical ridge continues to have a strong hold across the Southern Plains.
Early this evening the I-25 corridor, mtns and high valleys will see the greatest coverage of storms, but then as the evening progresses, the storms are expected to spread eastward across the plains, although it looks like locations from Highway 50 and north over the plains, will have the highest chances for storms, and the potential for a couple severe storms that could produce hail an inch or greater in diameter, and wind gusts of 60-70 mph. Temps on Mon should reach highs in the upper 80s to lower 90s, with the high valleys being in the upper 70s to lower 80s.
Very hot conditions will continue into Monday as the upper ridge remains in place and low-level moisture remains plentiful. The ridge will hold into Tuesday as well, with similar conditions expected.
1102 PM EDT Sun Aug 11 2019 Temperatures warm up Monday ahead of the next low pressure system, which will bring rain later Monday night into Tuesday. High clouds will be on the increase overnight from northwest to southeast as a cold front begins to approach the eastern Great Lakes. The increase in clouds should serve as a bit of an insulating blanket overnight, keeping temperatures about 5 degrees warmer than last night. The development of southwesterly winds will allow temperatures to climb about 5 degrees warmer than today's values. The cold front will cross Lakes Erie and Ontario Monday night and the local region Tuesday, with rain coverage likely peaking Tuesday morning.
432 AM EDT Mon Aug 12 2019 Upper air pattern consists of a trough in the Rockies and a trough off the east coast with a ridge across the southern half of the U. Moisture continues to be limited for this forecast and will continue with the low chance pops for the western cwa tonight.
As of 0130 PDT temps down to the 40s in lots of valleys, near 50 in the warmer ones, and even already down to 40 in parts of northern Elko County. Warmer today in ample sunshine, and warmer again Tuesday.
Meanwhile, a weak upper level disturbance is projected to eject out of the Southern Rockies into the high plains of western Kansas during the same time frame. Temperatures will not be quite as warm today in response to a weak cold front pushing through western Kansas later this afternoon. Highs are only expected to reach the lower 90s(F) across much of west central and southwest Kansas with the mid/upper 90s(F) likely in south central Kansas ahead of the boundary. With steepening low/mid level lapse rates and plenty of instability, thunderstorm development is likely across the high plains of eastern Colorado late Tuesday afternoon with storms then potentially drifting into west central and extreme southwest Kansas early to mid evening.
By late afternoon, we introduce another chance for thunderstorms across northeast Nebraska in association with a weak cold front moving out of the Dakotas. Mild temperatures are expected with highs in the lower to mid 80s.
With the center of the upper ridge drifting E over SW AR/N LA Monday, little if any convection is expected during the afternoon. /Tonight/ Even with the cu field having diminished with the setting sun, temps have only fallen slowly and still remain in the mid and upper 80s as of 0230Z, which are 0-2 degrees warmer than what was observed 24 hrs ago. A mostly clear sky should persist overnight, with the center of the H500 ridge expected to drift E into SW AR/N LA by daybreak Monday.
116 AM PDT Mon Aug 12 2019 Temperatures will get hot the next few days across central California as high pressure builds over the region.