Aikyam-Lab/Synoptic-Bench huggingface dataset:
941 AM EDT Tue Aug 29 2023 High pressure over northern Ohio this morning weakens as it moves to the east. A cold front moves across the central Great Lakes this afternoon reaching northwest Ohio by evening. The cold front then sweeps eastward into western Pennsylvania during the overnight hours.
Afternoon highs will peak today with many places being ~10 degrees above normal, and a slight decline in temperatures will occur Wednesday as a trough begins to push down the coast of California. With the trough moving in, the current location of the high pressure system will shift eastward, creating a more favorable monsoon pattern for northern Arizona. Model guidance is showing the track of the trough coming down the California Coast and sweeping across northern Arizona over the weekend.
During the day Tuesday, short range ensemble guidance agrees an upper level ridge currently centered over southern CA will begin its much anticipated eastward progression. Daytime Wednesday, the upper level ridge will continue its trek eastward, somewhat shunted by a strong upper level trough moving east from the far northwest CONUS into the far northern plains. Lee cyclogenesis will commence ahead of this trough across the northern plains, inducing southerly winds stretching all the way south into our area. This combined with increasing 850-mb temperatures should foster the beginning of a warming trend, with afternoon highs reaching the low/mid 90s. Key Messages: Expected prolonged dry stretch persists for southwest KS as upper level ridging dominates the weather.
Additional iso-sct convective development is expected across the region late this afternoon through early this evening as the fairly broad zone of midlevel lift spreads over the region, with the highest coverage generally east of I-27 as midlevel subsidence increases towards the TX/NM state line. Dry conditions and light winds continue area-wide Wednesday, but broadening upper troughing over the SE CONUS will keep the core of the ridge at bay for one more day, with temperatures Wednesday topping out in the upper 80s to middle 90s.
A formidable mid level ridge to the west and a trough to the east has kept the area under the aforementioned northwest flow. Further to the east low/mid level temperatures are slightly cooler, which is allowing the low level convective air mass to penetrate the warm nose aloft, creating some isolated to scattered showers. The mid levels will be more under the influence of the expanding ridge, which will spell more warm and dry weather going into the last of the week, into the weekend.
1224 PM CDT Tue Aug 29 2023 (Today and tonight) We get another day with northerly flow in the mid-levels as upper ridge remains well to the west. The lower dewpoints that continue to filter south will again allow cooler overnight temperatures as well with most of the area dropping into the 60s, with a few 50s across the far west and northwest.
152 PM MDT Tue Aug 29 2023 The main thing to note in the short term is the upper low and associated cold front moving though the region bringing strong winds. This evening, winds increase to more south/southeasterly as the low passes to our north along the Montana/Canada border. We are currently under upper ridging which is bringing temperatures around 10 degrees above average in the 90s for most of the region. The passage of the cold front and the trough coming through will drop temperatures 5-10 degrees in many locations Wednesday.
351 PM CDT Tue Aug 29 2023 A trough maintains it position over eastern Canada into the Ohio Valley; high pressure can be found to the west with another wave making its way onshore over the Pacific Northwest. There is a subtle upper level wave associated with the main trough moving south from Kansas into Oklahoma.
Otherwise, high pressure dominates the north, leaving us warm and quiet. Tomorrow, high pressure remains in our north and our area sits in a post frontal airmass. This will leave ridging aloft and high pressure at the surface across the Great Lakes region.
Northerly flow will continue into Wednesday with the mid-level ridge centered across the southwest U.
137 PM EDT Tue Aug 29 2023 Aviation A cold front approaching from the nw will bring increasing cloud cover today with showers and scattered convection.
In the upper levels a trough was over the eastern third of the country with a weak frontal boundary over the eastern and southern part of the forecast area.
Wednesday will see the 500mb high pressure continue to spread eastward over the panhandles region leading to continued dry and fair weather conditions. This high will cause a heating trend for the panhandles region which will see Wednesday highs increase to upper 80s to mid 90s.
Despite this, enough sunshine has warmed east-central Florida into the lower 90s.
---BMickelson MORNING DISCUSSION: Synoptic Setup: Forecast begins with hot high pressure situated over the Desert Southwest and a ridge jutting north through western Montana and cresting over northern Alberta. To the northeast an equally large opposing trough lies over the Hudson Bay and Ontario. Northeast Montana lies between these two features with the ridge rapidly gaining full dominance. Today through Tonight: Dry ridge will have the main influence during this time and allow a lee side mountain trough to begin to form to the west. As the ridge axis migrates east the lee trough strength will steadily increase the pressure gradient and wind out ahead of across the western zones late this afternoon into this evening.
Wednesday will be dry with highs in the low to mid 80s.
The 19Z MSAS surface analysis showed an area of low pressure over northern Lake Huron with a cold front that extended southwest through northeast IL. High pressure was located over the Canadian Prairie into ND. This trough was combining with daytime heating to produce isolated showers and sprinkles. Skies will clear for the rest of tonight as high pressure begins to build into the western Great Lakes region. This high pressure will be centered over the Great Lakes by Wednesday afternoon, thus bringing mainly sunny skies to northeast WI (once the fog burns off by mid-morning north).
What little upper level support was available for showers and storms will be moving out of the area and the ridge to the west will meander a little closer to the region and dry things out. Highs rebound back above average with many in the low 90s. Areas to the west stay slightly cooler thanks to elevation, but also have the best chances for rain. Wednesday remains quiet and a couple of degrees warmer than today should be.
239 PM CDT Tue Aug 29 2023 Isolated to widely scattered showers are popping up along a cold front over far southeast Iowa into central Illinois. This cold front will continue to move slowly to the south tonight into early Wednesday morning, driven by a short wave over the Great Lakes and high pressure dropping into the Upper Midwest.
/96 (Now through Wednesday) Weather through tomorrow will be dominated by a combination of Idalia passing well east of our forecast area later tonight into Wednesday and an upper level trough over the western half of the Southeast. High temperatures ranging from around 90 to the low 90s are expected. Tonight, northerly flow ushering in a bit cooler air will be counter-balanced by better mixing as winds remain in the 5 to 10 mph range combined with increased cloud cover limiting radiational cooling.
A cold front is moving through the area this afternoon and evening, which should usher smoke out of the area temporarily. Tonight looks to get a little cooler than what NBM is throwing out due to clearing skies.
(The rest of today ) At mid morning a weak mid level trof axis. the weak trof and vorticity lobe are expected to continue on their current trajectory into/across the CWA.
The high remains settled to our west, keeping rather dry air in place and really limiting the chances for any storm activity. Afternoon highs will peak today with many places being ~10 degrees above normal, and a slight decline in temperatures will occur Wednesday as a trough begins to push down the coast of California. With the trough moving in, the current location of the high pressure system will shift eastward, creating a more favorable monsoon pattern for northern Arizona. Model guidance is showing the track of the trough coming down the California Coast and sweeping across northern Arizona over the weekend.
1109 AM MDT Tue Aug 29 2023 There are very few concerns today as ridging will be in place across the Cowboy State and bring a nice late summer day for the most part with warm temperatures and mainly dry conditions. The only exception, may, and this is a big may, would be a stray shower or thunderstorm across the far northwest as a trough brushes by to the northwest. We will between an upper level low over Montana and a building ridge across the desert southwest. Temperatures will be quite warm, with 90s possible in the warmer locations.
138 PM EDT Tue Aug 29 2023 High pressure over northern Ohio this morning weakens as it moves to the east. A cold front moves across the central Great Lakes this afternoon reaching northwest Ohio by evening. The cold front then sweeps eastward into western Pennsylvania during the overnight hours.
(This evening through Wednesday Night) More quiet weather is expected through the short term, as northeast winds continue to advect a relatively cooler and less humid airmass into the region. Although, a few areas in SW Arkansas may only top out in the lower 90s. Slightly warmer overnight temperatures can be expected Wednesday night, with lows in the upper 60s to lower 70s. Continued NNE winds around 10 mph, with occasional higher gusts, could yield a rapid spread of wildfires once again given the low RH's expected.
The convection is gradually moving northeast with the highest amounts expected from the Smoky Mountains northeast towards southwest Virginia over the next few hours.
141 PM MDT Tue Aug 29 2023 A quiet and dry pattern has set up across the region this afternoon under a ridge of high pressure parked over the Central U. The ridge will be short lived though, as an evolving Pacific Northwest trough arrives onshore this afternoon. Tonight will remain quiet with clear skies and cooler temperatures, much like this morning. The passing wave to our north deepens into a closed low Wednesday afternoon. The stronger jet streak on the south side of the low glances our northern CWA. Surface winds will respond tomorrow to the warmer, drier conditions and the passing wave.
1023 AM MDT Tue Aug 29 2023 A trend towards warmer and drier conditions begins today as a strengthening upper-level ridge builds over the Four Corners region. Increasing 500 mb heights will help advect warmer air into the CWA and subsidence under the ridge will keep precipitation chances minimal. Temperatures today will be about 5 degrees warmer than yesterday, with highs making it into the upper 70s to upper 80s. As the ridge shifts further eastward, warmer and drier air will be ushered into the CWA. On top of this, a potent upper-level trough passing through Montana will steepen pressure gradients across the area, creating breezy to windy conditions.
/Issued 1250 PM CDT Tue Aug 29 2023/ /Today through Wednesday Afternoon/ A tranquil early week is in store for North and Central Texas as the region is planted between the longwave ridge to our west and a longwave trough to our east.
/NEW/ /Today through Wednesday Afternoon/ A tranquil early week is in store for North and Central Texas as the region is planted between the longwave ridge to our west and a longwave trough to our east.
126 PM CDT Tue Aug 29 2023 Northeast to north winds continue to bring cooler and drier air southward into our region. The pressure gradient between Idalia to our distant southeast and high pressure over the upper Mississippi Valley will produce breezy conditions on Wednesday. The models remain very warm and dry for the Labor Day weekend as a 500 mb ridge builds over our region.
238 PM CDT Tue Aug 29 2023 Widely scattered showers and thunderstorms will continue along a weak cold front for the next few hours. 19z/2pm surface analysis shows a weak cold front extending from southern Lake Michigan southwestward to northern Missouri. High pressure will bring sunny skies and comfortable highs in the middle to upper 70s on Wednesday.
(This afternoon through Wednesday night) A 500mb ridge will remain nearly stationary across the Desert Southwest portion of the U. , though the axis of the ridge will pivot from the Rockies into the Central Plains through the period which will shift flow from N/NNW to NE across west TX and eastern NM.
1247 PM CDT Tue Aug 29 2023 (Today and tonight) An upper level ridge will remain centered across the Desert Southwest on Tuesday, with West Central Texas on the periphery of the ridge.
The moisture is present in the low to mid levels to support these showers but will only be available through the rest of the afternoon before drier air pushes in with the higher pressure pushing in by the early evening in addition to the loss of diurnal heating. The pressure gradient will be increasing as the high pushes in impinging on the lower pressure to the southeast. Thus breezy north to northeast winds will continue through the night before gradually decreasing into the day Wednesday as higher pressure moves overhead and the upper ridge starts to nose in.
1111 AM PDT Tue Aug 29 2023 A robust cold front will bring showers and thunderstorms to the Inland Northwest today. Temperatures will drop today with cold front passage from west to east, and this will also result in gusty westerly winds.
A trough is moving across the Pacific NW this morning with thunderstorms extending from Joseph OR through eastern WA.
Another rain band developed and is now moving across the Lower Keys. A flood advisory was issued for portions of the Lower Keys from Key West to Boca Chica for excessive rainfall on top of already flooded streets.
Temperatures at 3 PM were mostly in the lower to mid 90s, with a north-northeast breeze. Temperatures will be a degree or two warmer than today, with highs mostly in the mid to upper 90s. An upper ridge will extend from the Desert Southwest across the central Plains, and the westernmost extent of an upper trough will shift slowly south across our area on Wednesday.
The resultant "cold" advection, along with drops in midlevel heights, has allowed for high temperatures to remain below the triple digit mark at most locations today (of course, values still do remain a few degrees above normals, which are in the low/mid 90s by the end of August). Perhaps the most noticeable result of the boundary passage will be a drop in overnight humidity as dew points look to remain in the high 50s to low 60s by daybreak tomorrow. Apparent temperature values will nonetheless be mitigated by lower dew point values, which should mix out into the lower 50s at many locations by the afternoon.
1222 PM CDT Tue Aug 29 2023 (The rest of today ) At mid morning a weak mid level trof axis. the weak trof and vorticity lobe are expected to continue on their current trajectory into/across the CWA.
338 PM EDT Tue Aug 29 2023 A cold front will drop across the region this evening bringing isolated to scattered showers mainly north of US 24. Some low clouds may filter in behind the cold front Wednesday morning, but mostly sunny skies and cooler conditions will return for Wednesday afternoon.
204 PM MDT Tue Aug 29 2023 Dry and sunny conditions are expected through the afternoon as a brief ridge axis passes through. Temperatures will peak warmer than yesterday, around five degrees above normal for most locations. By 00z the ridge will begin to be pushed out as a negatively tilted trough across the northwest extends toward Wyoming. The bigger impact from this trough will be fire weather conditions tomorrow. This will create elevated to critical fire weather conditions across the area as a dry cold front pushes east and winds respond to a tightened pressure gradient.
The heat will produce steep low level lapse rates which could end up creating a couple light showers over the higher terrain.
1159 AM CDT Tue Aug 29 2023 Updated aviation section for 18z taf issuance Quiet, dry, and cooler weather this week then warming up over the weekend. This is bringing us cooler and drier air over the next few days. We'll be cooler the next couple of days as this trof descends further over the Great Lakes then moves east. Expect breezy conditions tomorrow as we end up wedged between high pressure off to the northwest, and Idalia to the southeast.
Conditions slowly improve this evening and overnight with cooler temperatures once again on tap for tonight, Wednesday and Wednesday night.
1045 AM MDT Tue Aug 29 2023 Current surface analysis shows high pressure over much of the high plains, with light winds and mainly clear skies. Upper level analysis shows high amplitude ridge over the intermountain west and the Rockies, with weak northerly flow across the Plains. However, there is a weak circulation within the ridge over western MT, bringing a few showers there overnight. The front will stall out over the Black Hills area tonight and start to lift northeastward as a warm front by early Wednesday. Weakening ridge aloft will push over the Plains on Wednesday, bringing the warmest temps of the work week, with highs in the 90s across much of the Plains, 80s over the Black Hills.
1138 AM MDT Tue Aug 29 2023 Brief cool down today as drier and cooler air moves in from the east. Northeast flow aloft today with an elongated upper high centered over southern California. This will also allow for cooler and drier air to briefly move in place, with lowland highs in the upper 80s/lower 90s today. Rain chances diminish further Wednesday into the latter half of the week as the upper high progresses back over the southern Rockies.
Satellite imagery this afternoon highlights Hurricane Idalia over the Gulf of Mexico with a mid-level ridge situated across the southwest CONUS.
1052 PM EDT Tue Aug 29 2023 There will be spotty showers regionwide with a cold front moving through tonight. Meanwhile, a cold front across the central Great Lakes will push through the region late tonight. the aforementioned cold front will be exiting to our east. while its driving longwave trough will plow across our region to the St Lawrence valley. Forcing from the sharp longwave trough and diurnal instability will lend itself to producing more scattered showers. As low level moisture thins and high pressure approaches from the Upper Great Lakes late Wednesday and Wednesday evening. It will be a notably cooler night. as min temps will range from the lower 50s along the lake shores and southeast of Lake Ontario to the mid 40s most elsewhere.
Gusty winds up to 20 kts will likely occur late Wednesday morning into the afternoon due to the pressure gradient between the amplifying ridge to our west and Hurricane Idalia to the southeast. In addition, a weak cold front will move southerly through the area continuing the cooling trend seen within the past few days.
Temperatures remain on track in the upper 80s, with expectations of highs in the lower 90s this afternoon. By late this afternoon into tonight, upper troughing will continue to influence drier, cooler air into the region with upper, westerly flow dominating.
619 PM CDT Tue Aug 29 2023 (This afternoon through Wednesday night) A 500mb ridge will remain nearly stationary across the Desert Southwest portion of the U. , though the axis of the ridge will pivot from the Rockies into the Central Plains through the period which will shift flow from N/NNW to NE across west TX and eastern NM.
322 PM MDT Tue Aug 29 2023 The local surface pressure gradient is tightening between high pressure to our east and low pressure to our west. Trends from model 500 mb height field patterns show that the current small-scale low pressure system will quickly move northward through Montana, generating the gusty winds now through tonight - only to be quickly replaced by another low pressure system approaching on Wednesday, which will then shift the gusty winds around to come from the west. The wind shift on Wednesday morning will mark the cold front but temperatures will still be warm - topping out in the mid 80s for Glasgow and won't quite reach Sidney before high temps there top 90 degrees.
Overnight lows are still projected to be in the lower to middle 60s.
643 PM CDT Tue Aug 29 2023 A trough maintains it position over eastern Canada into the Ohio Valley; high pressure can be found to the west with another wave making its way onshore over the Pacific Northwest. There is a subtle upper level wave associated with the main trough moving south from Kansas into Oklahoma.
Dry, breezy, and very warm conditons are expected through late this afternoon and evening when a Pacific cold front brings a period of gusty showers and thunderstorms that will persist into the overnight hours.
340 PM MDT Tue Aug 29 2023 Dry, breezy, and very warm conditons are expected through late this afternoon and evening when a Pacific cold front brings a period of gusty showers and thunderstorms that will persist into the overnight hours.
As expected, strong thunderstorms initiated today with passage of the negatively tilted trough. The cold front has exited the region ending the breezy and dry conditions across southern Idaho promting the Red Flag Warning earlier. Furthermore, satellite has detected several active fires this evening in Southwest Idaho due to the low relative humidities and gusty winds today. Drier air behind a cold front will result in mostly sunny skies across the area on Wednesday.
750 PM CDT Tue Aug 29 2023 Widely scattered showers and thunderstorms along a weak cold front, will gradually dissipate as it approaches the I-70 corridor this evening. 00z surface map indicated a cold front stretched from northern IN southwest through central IL and into northern MO. Ahead of the front, a zone of convergence where dewpoints pooled in the lower 70s, was producing a broken band of showers. Winds veer north behind the front, then northeast later tonight, and begin transporting cooler and less humid air into the region. 25 19z/2pm surface analysis shows a weak cold front extending from southern Lake Michigan southwestward to northern Missouri. High pressure will bring sunny skies and comfortable highs in the middle to upper 70s on Wednesday.
535 PM MDT Tue Aug 29 2023 A quiet and dry pattern has set up across the region this afternoon under a ridge of high pressure parked over the Central U. The ridge will be short lived though, as an evolving Pacific Northwest trough arrives onshore this afternoon. Tonight will remain quiet with clear skies and cooler temperatures, much like this morning. The passing wave to our north deepens into a closed low Wednesday afternoon. The stronger jet streak on the south side of the low glances our northern CWA. Surface winds will respond tomorrow to the warmer, drier conditions and the passing wave.
901 PM EDT Tue Aug 29 2023 A cold front will swing through the Ohio Valley tonight with another surge of cooler air on tap for Wednesday in the wake of the front. A cold front will move through the area from north to south tonight. With the cool northerly breezes, and low clouds, temperatures will be slow to respond especially central Ohio where it may take much of the day to get into the lower 70s in some spots. A little warmer further south, but again how long the clouds hold in will determine full warming potential. Best chances for fuller sun/warmer temps will be across northern KY and southeast IN.
Wrap around clouds on the back side of the low will pivot through the area tonight. These clouds may also be aided by the lakes as Delta T's are in play tonight given warm water and overriding cooler air. Conditions slowly improve this evening and overnight with cooler temperatures once again on tap for tonight, Wednesday and Wednesday night.