Aikyam-Lab/Synoptic-Bench huggingface dataset:
Southwesterly flow aloft continues through the period as our region remains sandwiched between an upper- level ridge, which extends from the Eastern Gulf towards Bermuda, and an upper-level trough, which extends from the Great Lakes to Texas. With the high moisture values and wet antecedent conditions in place, the primary concern for both days will be slow-moving, training storms capable of producing heavy rainfall, which could lead to localized flooding concerns. Additionally, 0-6km bulk shear values will generally be around 20 to 25 kts, with the highest values over southeast Mississippi and southwest Alabama. Highs for both Monday and Tuesday will range from the mid to upper 80s west of I-65, to the low 90s for areas east. Lows will generally be in the low 70s, with mid to upper 70s along the coast.
1249 AM CDT Mon Sep 5 2022 (This evening through Monday) We will continue to sit between the high pressure across the western U. and the low pressure across eastern Texas.
Vertically integrated smoke will remain elevated into Monday with some improvement near surface during the day, but it may take until a cold front pushes through by Monday evening into Monday night before conditions markedly improve. The semi- permanent upper ridge over the western states will resume it's reign over the area and keep things hot and dry across the area another day. But the flow across Montana late Monday becomes zonal and introduces a cold front.
Highs should top out in the lower to mid 80s across the area today. Better mixing winds from the southwest are forecast Tuesday which should push highs into the low 90s in our western counties to the mid 80s across western Iowa.
Daily record high temperatures remain in jeopardy today and tomorrow with widespread upper 90s to near 100 degree readings likely across the lower elevations.
1040 PM MDT Sun Sep 4 2022 Current analysis shows a large scale ridge across the western CONUS extending into the plains, with an embedded weak short wave over northeastern Montana. At the surface, a trough associated with the short wave is slowly moving eastward into northeastern Wyoming and northwestern South Dakota. Breezy to windy southeast/south winds are occurring ahead of the trough, over western South Dakota with somewhat lighter winds to the west.
Will confine POPs to the southeast where the progged CIN is the lowest in the NAM and ECMWF. Confidence is not as high in this area as farther south, and it will somewhat depend on how much the low-level moisture mixes out here, so will not add POPs in this area right now, but will keep an eye on the mesoanalysis trends in this area today.
300 AM CDT Mon Sep 5 2022 Early morning water vapor imagery clearly shows circulations within the mean mid level trof from southern Lake Michigan to near St. Tonight, as some support aloft moves east within the parent trof, the convective chances will follow suit.
Prevailing tranquil conditions will continue today and tonight as a broad upper level ridge of high pressure remains in control throughout the entire western conus, including the Western High Plains. A relatively weak northeast flow aloft combined with a much drier air mass in the lower/mid levels limiting instability, will keep precip chances at bay in western Kansas through the period. Temperatures will bump up a little today as prevailing low level south-southeasterlies draw warmer air back into western Kansas. Afternoon highs in the lower to mid 90s(F) can be expected. The ongoing stagnant dry/warming pattern will persist through the middle of the week as models indicate upper level ridging further building across the Intermountain West, expanding well into the Northern and Central Plains.
355 AM EDT Mon Sep 5 2022 Showers with embedded thunderstorms are possible through midweek due to a slow moving low pressure system. The frontal boundary should gradually move southeast through Tuesday in conjunction with slow eastward movement of the upper trough. Long range model ensembles indicate low pressure having a difficult time clearing the Mississippi and Ohio River valleys. Restrictions are likely through Wed with a slow movg trough.
Also, there could be a little added surface convergence along a trough which could be near the Caprock in the south-central/southeast Texas Panhandle this afternoon.
Accordingly, forecast high temps for today have been nudged cooler. High temps are expected be a few degrees warmer than today--topping out in the mid 70s. Aloft, an anomalously strong mid/upper anticyclone will remain centered over the Great Basin into Thu, with an associated ridge axis extending NE into the western Great Lakes, facilitating large-scale subsidence and settled weather for the forecast area. A NE Pacific trough is expected to reach British Columbia on Wed, likely inducing surface cyclogenesis over Alberta/Saskatchewan. This trough should crest/flatten the western CONUS mid/upper anticyclone, then possibly interact with the remnant Gulf cutoff low (and its deep moisture plume) on Fri/Sat. Still, sizable ensemble spread in the 500-mb height field suggests that the details of this trough/low interaction and possible phasing are uncertain, as are the particulars of frontal placement and possible secondary cyclogenesis.
Tonight Through Tuesday Main focus through the short term remains the H500 low/trough that is oriented from south of Chicago to northeast Texas.
322 AM EDT Mon Sep 5 2022 Not much change in the pattern from the past couple of days, with the upper trof axis still extending from Michigan southwest across the STL area and into the ArkLaTex.
1254 AM EDT Mon Sep 5 2022 Showers with embedded thunderstorms are possible through midweek due to a slow moving low pressure system. The frontal boundary should gradually move southeast through Tuesday in conjunction with slow eastward movement of the upper trough. Long range model ensembles indicate low pressure having a difficult time clearing the Mississippi and Ohio River valleys. Restrictions are likely through Wed with a slow movg trough.
By mid week, rain chances will end from north to south, as high pressure becomes dominant over the Great Lakes. An upper level trough remains nearly stationary over the Midwest, with a positively tilted axis from the upper Great Lakes through Arkansas. Upper level low pressure continues to spin across the St. The upper low will meander across the region through Monday, with more of the surface reflection closer to the Ohio River.
342 AM CDT Mon Sep 5 2022 Today and Tonight: This Labor Day will feature a continuation of cooler than normal afternoon highs with above normal rain chances. Early morning water vapor imagery/RAP analysis showed a southwest to northeast oriented upper level trough axis just to the northwest of our CWA. 20inches and surface dew points were running in the low to mid 70s. Afternoon highs today will again be held to the mid 80s for much of the area while Tuesday morning lows continue to bottom out several degrees above normal and mainly in the lower 70s.
WV imagery indicates ridging aloft remaining centered across the Great Basin. Near the surface, a weak lee side trough of low pressure is anchored in eastern Colorado. Infrared satellite imagery revealed the scope of this anticyclone's subsidence field, with a clear sky across all of the Great Basin, Rockies, and Great Plains.
Each afternoon we should expect showers and storms as this upper trough sticks around for the week.
137 AM MDT Mon Sep 5 2022 Water vapor shows large scale upper ridge over the Great Basin extending into the Plains, with weak short wave over ND. At the surface, trof is advancing slowly eastward through the western Dakotas. Daily highs will be in 90s to around 100, with only slightly cooler temps in the higher hills.
Models are in agreement that a stronger system will further knock the ridge down late in the week but disagree on how quickly it will rebuild and if troughing will linger over the upper Great Lakes. Locations along Lake Superior over the west may stay a bit warmer with southerly downslope winds keeping things mixed through the night.
Lots of 50s for lows tonight, but some of the typically cooler/interior spots falling into the 40s is a good possibility.
An upper ridge will build into the area Monday-Tuesday for dry, warmer weather.
A weak upper level trough may help trigger a few brief afternoon/evening showers and storms through Tuesday.
255 AM CDT Mon Sep 5 2022 Quiet weather is expected during the period as ridging is expected to dominate the western U. S with weak troughing over the Lower Mississippi Valley.
By mid week a mid level trough could settle into the northern Gulf region, increasing instability and moisture over the area and rain chances are expected to be higher. In terms of temperature, highs in the low to mid 90s with overnight lows in the mid to upper 70s. High pressure at the surface continues to dominate weather conditions over the waters for the next days.
Today through Tuesday we will see high pressure remain anchored over Quebec. These clouds will burn off through the morning, with a cu field only expected to hang around in south central MN, where dewpoints look to remain in the low 60s. For Tuesday, a mid-level trough going across the northern Saskatchewan and Manitoba border will send a weak cold front into northwest MN.
(Today) Weak upper low, currently over eastern Oklahoma will drift slowly south into far southeast Oklahoma today.
1212 AM CDT Mon Sep 5 2022 (This evening through Monday) Convective initiation has begun along a weak cold front that is supported by some outflow from an MCS that originated over central Oklahoma earlier today. At this time no defined surface boundaries are expected for tomorrow afternoon, although some confluence near the Caprock escarpment and into the lower end of Palo Duro Canyon could result in some isolated thunderstorms.
Central Alabama is on the eastern side of a stationary upper trof and this persistent wet pattern will continue into this week. An upper ridge over the northeastern Gulf of Mexico will push drier mid level air northward into south Alabama today and into Tuesday. Showers will be the dominate weather type again today with only isolated thunderstorms due to saturated vertical moisture profiles and cooler than normal temperatures. A stronger short wave trof moving through the Ohio Valley States on Tuesday will take some of the energy away from the Mississippi River trof with overall lower rain chances on Tuesday, as most of the better forcing stays north of Alabama.
With extremely warm overnight lows occurring (Billings airport didn't drop below 70) and quick mixdown of warmer temps aloft occurring, temperatures quickly rose into the 90s today, with Sheridan reporting a temperatures of 99 as of 2 PM. MOnday's temperatures will be a couple degrees cooler, but Tuesday looks to be the 'coolest' day of this heat stretch, as we will see some northeast winds flowing into the area.
1046 PM CDT Sun Sep 4 2022 The meandering mid/upper level low is currently near the Mississippi River early this afternoon. Water vapor imagery shows multiple vorticity maxima rotating cyclonically around the closed low. This will help serve to "stretch" out the lower heights aloft with more of a shear axis draped from southwest to northeast across the bi-state area. We lose almost all of the low-level moisture convergence we had the past couple of nights.
The Florida Keys and coastal waters currently are situated at the base of a weakening ridge along the Eastern Seaboard. Regardless, there appears to be a 100mb or so layer of drier air just above the freezing level.
617 AM CDT Mon Sep 5 2022 (Today and tonight) Upper-level ridging continues to reside across the Four Corners this morning with troughing across eastern Texas. With afternoon temperatures warming into the low to mid 90s area wide, convective temperatures may be reached east of the Caprock escarpment where convergence will be maximized. While the blended model data tended to produce PoPs near 0% have gone ahead and increased these values to 10% to account for any isolated activity that may develop as depicted by a few of the high resolution model guidance.
Predawn temps ranged fm the mid 60s to the lower 70s. The persistent upper trof fm the Great Lakes region into NE TX wl cont to linger acrs the FA in the short term.
A strong high pressure system over the western United States will remain in place through the middle of the week. High pressure will weaken toward the end of the week leading to decreasing temperatures and an increasing chance of thunderstorms as monsoon moisture spreads back into Arizona. Anomalously strong high pressure continues to be centered over Nevada and Utah this morning keeping a warm and dry air mass over northern Arizona.
633 AM CDT Mon Sep 5 2022 Key Messages: - Continued quiet, some clouds and fog potential tonight - Warming into midweek - Rain chances looking more likely heading into weekend A dome of high pressure aloft remains centered over the Great Basin with ridging extending into the Upper Midwest.
Upper ridging continues, with another relatively quiet period expected across southern Colorado. This increase in large scale ascent coinciding with low/mid level troughing will support isolated showers and thunderstorms this afternoon. 2) Some afternoon showers and thunderstorms will be possible here and there over the higher terrain. The upper level high will persist overhead through the end of the work week, leading to hot and dry conditions across our area. Temperatures will be far above normal values, with highs in the mid- 90s to near 100 over the plains and only slightly lower over the higher terrain.
Strong upper level ridging and upper level high pressure will result in a dry forecast for western and north central Nebraska. Confidence remains high that highs across the region will rise into the 90s today and even warmer into the mid 90s to low 100s on Tuesday.
Drier air will dip into the northern counties as the mid-upper level trough shifts east. As for Tuesday, isolated to scattered showers and thunderstorms remain possible as the trough continues a southeastward progression. Northern counties could see slightly warmer temperatures as cloud cover decreases.
520 AM MDT Mon Sep 5 2022 Water vapor shows large scale upper ridge over the Great Basin extending into the Plains, with weak short wave over ND. At the surface, trof is advancing slowly eastward through the western Dakotas. Daily highs will be in 90s to around 100, with only slightly cooler temps in the higher hills.
Southeast Michigan is feeling the early stages of upper level blocking ridge with prevailing northerly surface wind trajectories holding overnight. Given the influence of high pressure, the quasi stationary surface front has been shoved south of the Michigan stateline from roughly Sandusky OH, to Findlay, to just south of Fort Wayne IN. Amplification of the upper level ridge will then take place for the end of the week.
Southwesterly flow aloft persists as our region remains sandwiched between an upper-level ridge to our east and upper-level trough to our west. 1 inch range with the highest values over southeast Mississippi at this hour. HREF ensemble guidance indicates that this plume of rich, Gulf moisture will persist today with a slight decline in moisture by Tuesday as the ridge aloft attempts to briefly build west into the region. Highs will top out in the mid to upper 80s for locations generally west of the I-65 corridor with low 90s east of I-65 this afternoon with a few more spots rising into the 90s on Tuesday (given the lower convective coverage). Lows remain in the low 70s inland with mid to upper 70s at the beaches.
RAP Mesoanalysis shows a 596dm upper level ridge centered over Utah this morning, and this ridge is expected to strengthen through the day today while remaining nearly stationary. We'll likely flirt with 100F across most of our plains this afternoon with mid-level temperatures 1-2C warmer than yesterday. It did appear that the 00z analysis from both models was a touch warmer than the observed GJT sounding last evening, so I think most spots will remain in the upper 90s. Either way, that's splitting hairs for a forecast that is frankly much warmer than I want to see in September. The only other note for the short term period will be a slight chance of showers across the high country during the afternoon hours.
605 AM CDT Mon Sep 5 2022 (Today) Weak upper low, currently over eastern Oklahoma will drift slowly south into far southeast Oklahoma today.
Guidance continues to support additional widespread convection heading through the late morning and afternoon hours with a stalled trough and associated boundary over the area. Dense cloud cover from these showers and storms will result in a cooler day and below normal high temperatures in the low to mid 80s.
Not much change in the pattern from the past couple of days, with the upper trof axis still extending from Michigan southwest across the STL area and into the ArkLaTex.
Near normal temperatures today will warm a few degrees on Tuesday with an upper ridge.
540 AM EDT Mon Sep 5 2022 Showers with embedded thunderstorms are possible through midweek due to a slow moving low pressure system. The frontal boundary should gradually move southeast through Tuesday in conjunction with slow eastward movement of the upper trough. Long range model ensembles indicate low pressure having a difficult time clearing the Mississippi and Ohio River valleys. Restrictions are likely through Wed with a slow movg trough.
734 AM EDT Mon Sep 5 2022 Showers with embedded thunderstorms are possible through midweek due to a slow moving low pressure system. Showers with an embedded thunderstorm will continue through the day and overnight as low pressure makes little progress in its eastward movement. The frontal boundary should gradually move southeast through Tuesday in conjunction with slow eastward movement of the upper trough. Long range model ensembles indicate low pressure may linger in the OH Valley. Restrictions are likely through Wed with a slow movg trough.
644 AM CDT Mon Sep 5 2022 Quiet weather is expected during the period as ridging is expected to dominate the western U. S with weak troughing over the Lower Mississippi Valley.
Rain chances return late week with cooler temperatures for the weekend. High pressure was centered over Lake Superior early this morning. While high pressure will remain in place at the surface today, an upper low and trough will move from northwest to southeast across the region.
610 AM CDT Mon Sep 5 2022 Early morning water vapor imagery clearly shows circulations within the mean mid level trof from southern Lake Michigan to near St. Tonight, as some support aloft moves east within the parent trof, the convective chances will follow suit.
303 AM MDT Mon Sep 5 2022 Satellite imagery shows clear skies across the region overnight with the high centered over eastern Nevada.
511 AM MDT Mon Sep 5 2022 Satellite imagery shows clear skies across the region overnight with the high centered over eastern Nevada.
640 AM CDT Mon Sep 5 2022 (Monday through Tuesday) A fairly stagnant pattern to persist through the short-term period characterized by an upper-level trough as well as a weak surface boundary lingering across the region. However, it should be noted that each day will not be a washout by any means despite persistent upper-level troughing that is expected to remain in place this week. This pattern will be largely driven by the massive upper-level ridge out west while the Bermuda High maintains its usual residence across the western Atlantic, effectively pinning the trough over much of the eastern CONUS. Given the trough axis placement generally along the Mid and Lower MS Valley, expect the heaviest rainfall amounts to remain well east of our region throughout the week.
High pressure is strengthening, and combined with surface pressure gradients that are trending a little more toward offshore, current temperatures are running around 5 degrees milder compared to 24 hours ago. Forecast remains on track with a record-setting, both in magnitude and duration, period of dangerous heat forecast this week as strong high pressure builds west into NorCal. Elevated moisture and instability working its way northward around the periphery of the high may bring a slight chance of late-day thunderstorms to the northern Sierra beginning Tuesday.
Our area will remain situated between the Great Basin upper high and low pressure over the Arklatex. Carrying a 20-40 percent chance of PoPs for this afternoon and evening, with the highest PoPs across our southeastern counties. Outside of any showers and storms, it will be mostly sunny and warm, with temperatures climbing into the lower to middle 90s.
/22/ Today and Tonight: This Labor Day will feature a continuation of cooler than normal afternoon highs with above normal rain chances. Early morning water vapor imagery/RAP analysis showed a southwest to northeast oriented upper level trough axis just to the northwest of our CWA. 20inches and surface dew points were running in the low to mid 70s. Afternoon highs today will again be held to the mid 80s for much of the area while Tuesday morning lows continue to bottom out several degrees above normal and mainly in the lower 70s.
Afternoon highs in the low to mid 90s inland and around 90 along the coast.
1100 AM MDT Mon Sep 5 2022 Water vapor shows large scale upper ridge over the Great Basin extending into the Plains, with weak short wave over ND. At the surface, trof is advancing slowly eastward through the western Dakotas. Daily highs will be in 90s to around 100, with only slightly cooler temps in the higher hills.
250 PM EDT Mon Sep 5 2022 Weak high pressure will remain across the region through midweek then an upper level trough moving across the eastern U. is expected to cutoff over the Lower Mississippi Valley late in the week before getting absorbed into the next trough moving through the central U.
A positively tilted longwave trough oriented from the New England area into southern Louisiana will remain quasi-stationary keeping temperatures seasonably mild with afternoon showers and thunderstorms possible each day. A cutoff low is likely to develop over on the south end of the trough over south Louisiana after midweek.
An upper trof which extends from the Great Lakes into eastern Texas advances a bit eastward during the period while an upper ridge persists over the northeastern Gulf to across the Florida peninsula.
Upper level ridge remains over Idaho in the short term period with continue very hot conditions through Tuesday with low elevation highs in the 90s again with some locations reaching 100 degrees again. Winds will generally be light on Tuesday ahead of an approaching cold front.
349 PM EDT Mon Sep 5 2022 Shower and embedded thunderstorm chances will slowly lower through midweek as a slow moving low pressure system shifts east of the region. Will maintain Flood Watch highlights as a localized flooding threat remains with slow storm motion, but that threat is on the lower side at this time and is expected to lower til its expiration.
1217 PM CDT Mon Sep 5 2022 (Today and tonight) Upper-level ridging continues to reside across the Four Corners this morning with troughing across eastern Texas. With afternoon temperatures warming into the low to mid 90s area wide, convective temperatures may be reached east of the Caprock escarpment where convergence will be maximized. While the blended model data tended to produce PoPs near 0% have gone ahead and increased these values to 10% to account for any isolated activity that may develop as depicted by a few of the high resolution model guidance.
An upper level trough has been over the Great Lakes the last few days, unable to make much progress eastward as a strong blocking pattern has been in place with a ridge over the SE conus and another over the western half of the conus. Models show the SE conus ridge to be breaking down tonight and tomorrow allowing forward propagation of the longwave pattern to commence.
100 PM CDT Mon Sep 5 2022 Quiet weather is expected during the period as ridging is expected to dominate the western U. S with weak troughing over the Lower Mississippi Valley.