Aikyam-Lab/Synoptic-Bench huggingface dataset:
539 PM MDT Mon Jul 18 2022 The mid-level cyclone moving along the northwest U. /Canadian border nudged the high center to northeast New Mexico overnight. Storms have formed over the higher terrain and has struggled to move off over adjacent lower elevations. Drying begins tonight as the trough to the north moves to the northern Plains allowing high pressure to retrograde to the west causing the subtropical moisture stream to lift to the north.
525 PM MDT Mon Jul 18 2022 20Z analysis shows the upper ridge beginning to be shunted to the east as an upper low tracks eastward along the northern Montana border. At the surface, a weak low pressure center is currently tracking eastward across northern Meade and Ziebach counties. The trough/warm front ahead of the circulation has currently pushed in to north central South Dakota while a dryline extends southward into Nebraska. Dewpoints over far western South Dakota are in the lower 50s, with 40s in northeastern Wyoming.
Overnight lows will be in the low to mid 70s, with a few locations making it to the upper 70s.
639 PM CDT Mon Jul 18 2022 (This evening through Tuesday Night) Upper-level ridge centered across the Four Corners region to continue to intensify with the ridge axis to extend eastward into Texas and across the ArkLaTex into Mississippi by Tuesday night. Subsidence associated with the upper-ridge will maintain the ongoing hot pattern.
Winds will calm briefly between 12Z and 18Z as a cold front approaches with winds shifting to the north around 18Z around 10 to 15 kts. The hottest day of the week will be Tuesday as the upper level ridge of high pressure remains in our vicinity. As the upper level ridge of high pressure begins to slide westward towards the four corners region Tuesday evening, the steering flow may become a bit more favorable for bringing showers and thunderstorms into the western sections of the area Tuesday evening, and have incorporated the NBM slight chance pops for this time period.
939 PM EDT Mon Jul 18 2022 The quasistationary upper-level pattern continues with ridging in the west and troughing over the eastern US.
Storms have been developing over the higher terrain E and SE of Tucson this afternoon. The center of the upper high, which was over southern Colorado this morning, will be migrating about across the desert southwest this week.
Showers will be exiting the Highline region overnight with clear skies expected tomorrow. A cold front slides across the area, favoring developing thunderstorms, some of which become severe. Weak ridging aloft settles in the wake of the departing H500 low for a return to mostly dry conditions with afternoon temperatures in the 90s for most lower elevation locations.
954 PM EDT Mon Jul 18 2022 High pressure will build into the Ohio Valley tonight.
630 PM CDT Mon Jul 18 2022 (Tonight) A mid/upper trough will continue to drop SE from the Mid South into the Tennessee Valley this afternoon/evening into tonight. For tonight, we'll still be dealing with additional cloud cover and showers/storms with the passing mid/upper trough. Otherwise, expect a fairly muggy, mild night with lows in the low to mid 70s once again.
625 PM CDT Mon Jul 18 2022 (Tonight through Tuesday night) An oppressive upper ridge remains situated to the NW of TX which is typically the mid-summer pattern that is capable of bringing some of the most extreme heat. While our 24 hour trend monitoring hasn't been very consistent from one location to the next, we'd rather wait until the highs of the day are reached so that the later shifts can assess the best choice of areas for the Excessive Heat Warning if any. The position of the ridge axis also leads to limited evening winds which is a good reason to just run the Heat Advisory around the clock.
* None Flattening upper ridge has begun expanding across the central Great Lakes today allowing the hotter airmass across the upper Midwest to be advected southeast into lower MI. Ridge axis crosses the area Tuesday veering flow southwesterly resulting in strengthening of ongoing advection allowing 850mb to approach 20C which supports widespread highs in the low 90s.
89 inches, which means that the Lower Keys are right on the western periphery of the incoming dry air. Forecast soundings show drier air becoming much more prevalent in the lower to mid-levels, which is classic of a Saharan Air Layer.
Light east to south winds overnight will shift to the southwest and increase Tuesday morning in response to deepening low pressure in the TX Panhandle. Low-level thicknesses will peak tomorrow afternoon as the persistent high pressure located over the Four Corners is nudged eastward. We have sided on some of the warmer model guidance for tomorrow afternoon's high temperatures due to breezy southwest winds off the higher elevation. The persistent subtropical ridge positioned over the southwest CONUS will maintain its dominance in the synoptic pattern, showing very little of the 'tropical' portion of its nomenclature.
820 PM MDT Mon Jul 18 2022 20Z analysis shows the upper ridge beginning to be shunted to the east as an upper low tracks eastward along the northern Montana border. At the surface, a weak low pressure center is currently tracking eastward across northern Meade and Ziebach counties. The trough/warm front ahead of the circulation has currently pushed in to north central South Dakota while a dryline extends southward into Nebraska. Dewpoints over far western South Dakota are in the lower 50s, with 40s in northeastern Wyoming.
(This evening through Tuesday) Afternoon water vapor imagery shows the upper level ridge of high pressure spinning across the Desert Southwest. Subsidence from the upper ridge combined with abundant sunshine is resulting in a very hot day across west central Texas. For Wednesday, the western extent of the upper ridge will nudge eastward and 850 mb temperatures will increase to 30 to 33 degrees C.
High temperatures in the mid 80s to low 90s will be close to seasonal norms today but temps rise into the low 90s to mid 90s Wed. 01 NW flow aloft during the middle of the week, with a longwave trough just offshore.
Showers will be exiting the Highline region overnight with clear skies expected tomorrow. A cold front slides across the area, favoring developing thunderstorms, some of which become severe.
Low pressure across the TX/OK border and a front developing in OK has kept winds stronger overnight than previously anticipated and therefore, winds will be stronger on Tuesday. Rain chances minimal with high pressures still overhead in Southeast Texas. We've seen many locations with high temperatures in the triple digits as of 3 PM today, and as the upper ridge remains dominant over the area we should see a slight warming trend over the next several days.
1058 PM MDT Mon Jul 18 2022 The mid-level cyclone moving along the northwest U. /Canadian border nudged the high center to northeast New Mexico overnight. Storms have formed over the higher terrain and has struggled to move off over adjacent lower elevations. Drying begins tonight as the trough to the north moves to the northern Plains allowing high pressure to retrograde to the west causing the subtropical moisture stream to lift to the north. A westward shift in ridge does not favor strong monsoonal moisture advection for the West Slope, however, recycled moisture circulating under the high will maintain afternoon convection Wednesday onward. Therefore, high pressure settled over the Desert Southwest will retain above average temperatures across the area. Small perturbations rippling across the ridge axis, combined with residual moisture, diurnal and orographic influences will help trigger thunderstorms each afternoon.
Mainly a forecast of persistence with upper level ridging dominating area wx. Temps on Wed will probably be a degree or two warmer than today.
1038 PM MDT Mon Jul 18 2022 Sent an update to cancel the High Wind Warning early for Central Valley and Central Phillips Counties. Will cancel advisory along the Canadian Border where highs will be in the lower to mid 90s. Upper low will move east along the MT/Canada border this afternoon and tonight. A cold front will move across NE Montana in the late afternoon and early evening. Strong west to NW wind are expected behind the cold front tonight and Tuesday. A second round of showers and thunderstorms are possible late tonight and Tuesday morning mainly in the north as the wrap around precipitation with the upper low moves through the area. Temperatures warm into the 90s in most areas late in the week with upper ridge.
A weak upper-level trough will slowly move over the Appalachians and portions of the Southeast through Wednesday as a potent upper-level ridge dominates over much of the western US. Down at the surface, high pressure maintains its hold over the Atlantic, with a ridge axis extending across the Florida peninsula and into the Eastern Gulf of Mexico. Highs on Tuesday and Wednesday will climb into the lower to mid 90s inland with upper 80s along the coast.
Storms will form again midday around 18Z, generally favoring the northeast quadrant of the state thanks to a backdoor cold front. A 597dm H5 high center focused over central NM today will elongate into more of a ridge from west to east thru Tuesday. Very hot temps will continue beneath the upper high with several areas expected to break or tie record highs, especially Tuesday.
Any more established updrafts may be capable of briefly enhancing the transfer of the higher momentum air aloft to the surface with an occasional gust to around 50 mph possible. Today: Surface cold front entering central SD as of 7z this morning being tugged along by a seasonally anomalous deep low pressure passing through the Dakotas. Terrain favored areas such as the Buffalo Ridge also likely see some of the stronger synoptic gusts, perhaps nearing 45 mph. Tonight: Closed mid/upper level low slides into northern MN by tonight with likely breezy conditions continuing to channel through the base of it, especially for areas north of I-90.
The upper level ridge that has been the primary controller of our weather will continue to slide to the east today.
Wednesday through Wednesday night: Mid level cyclonic flow will linger with some low level troughiness as well.
Discussion: The upper trough centered over the area will continue to shift slowly east during the period.
An upper level low situated over the northern Great Lakes will bring warm air associated with a quasi stationary boundary down through the region. This and a mid to low level ridging through the western portion of the state will preclude any widespread convection. Latest HREF gives indication for the chance for scattered convection but that shouldn't occur until the passage of a cold front with a low level jet tonight into tomorrow. A large upper level low will move through the northern Great lakes through the week. This low will deepen and intensify as it moves eastward. The upper level low will drift east and northward and should merge with a larger low.
1110 PM EDT Mon Jul 18 2022 Warm, humid, and dry weather will resume tonight, and will be interrupted by the approach of another cold front on Wednesday. Great Lakes ridging will result in a dry and sunny Tuesday, with seasonable temperature. Warm and moist advection will continue with swly flow through Wednesday, prior to the peripheral passing of low pressure in the northern Great Lakes that will lend a frontal passage and provide precipitation chance. High pressure wl return genl VFR to area terminals this evening, but llvl moisture beneath a subsidence inversion should support areas of MVFR/IFR fog development after midnight, continuing through early Tues. The next chc for genl restrictions is expected with a late- Wednesday cold front.
This will allow for temperatures to top out warmer from the west today and combine with high humidity to result in heat index values between 106F and 110F generally west of Interstate 55 and near 105F east of Interstate 55.
While temperatures will remain very warm with increasingly humid conditions, will back off on highs just a bit over the northern parts of the forecast area as timing of cold front (or at least pre-frontal trough) may support isolated to scattered showers or thunderstorms fairly early in the day. Convective chances will then translate southeast through the area as low level convergence with the features support additional convective development within an increasingly unstable air mass as temperatures once again reach 90 or more over at least the southern half of the forecast with with dew point temperatures solidly into the lower 70s by this time.
A strong upper level cut-off ridge is locked in place over the Southern Rockies/Desert Southwest, as per recent RAP analysis. Tuesday night, as the upper level impulse continues to dig into the upper Midwest/Great Lakes, the upper level cut-off ridge will be forced to retrograde just enough to allow a stronger push of cold air into southwest KS. A lot will depend on how the low level thermal and wind fields shake out.
202 AM MDT Tue Jul 19 2022 07z surface analysis had cold front from central ND to Hot Springs to central WY. Upper low depicted by water vapour spinning along the northeast MT/Canadian border.
1215 AM CDT Tue Jul 19 2022 (Tonight through Tuesday night) An oppressive upper ridge remains situated to the NW of TX which is typically the mid-summer pattern that is capable of bringing some of the most extreme heat. While our 24 hour trend monitoring hasn't been very consistent from one location to the next, we'd rather wait until the highs of the day are reached so that the later shifts can assess the best choice of areas for the Excessive Heat Warning if any. The position of the ridge axis also leads to limited evening winds which is a good reason to just run the Heat Advisory around the clock.
404 AM EDT Tue Jul 19 2022 Weak ridging will build over the area today and hold through Wednesday.
1241 AM CDT Tue Jul 19 2022 (This evening through Tuesday Night) Upper-level ridge centered across the Four Corners region to continue to intensify with the ridge axis to extend eastward into Texas and across the ArkLaTex into Mississippi by Tuesday night. Subsidence associated with the upper-ridge will maintain the ongoing hot pattern.
Light east to south winds overnight will shift to the southwest and increase Tuesday morning in response to strengthening low pressure in the Texas Panhandle. Low-level thicknesses will peak tomorrow afternoon as the persistent high pressure located over the Four Corners is nudged eastward. We have sided on some of the warmer model guidance for tomorrow afternoon's high temperatures due to breezy southwest winds off the higher elevation. The persistent subtropical ridge positioned over the southwest CONUS will maintain its dominance in the synoptic pattern, showing very little of the 'tropical' portion of its nomenclature. There has been a consistent signal for slight chance POPs over the higher terrain of eastern New Mexico tomorrow and Wednesday evening, wandering eastward into our northwest zones.
The anomalously deeper July system is on track to shift through the Great Lakes through Wednesday, with a cold front moving through in the late afternon and evening Tuesday. Further south into more capping and south of the deeper trough forcing, would think storms will be more isolated/"iffy".
1242 AM CDT Tue Jul 19 2022 (This evening through Tuesday) Afternoon water vapor imagery shows the upper level ridge of high pressure spinning across the Desert Southwest. Subsidence from the upper ridge combined with abundant sunshine is resulting in a very hot day across west central Texas. For Wednesday, the western extent of the upper ridge will nudge eastward and 850 mb temperatures will increase to 30 to 33 degrees C.
402 AM EDT Tue Jul 19 2022 Weak ridging will build over the area today and hold through Wednesday.
As surface and upper low along with accompanying surface cold front move across the Upper Lakes/U. Northwesterly winds behind the low will yield dangerous swimming conditions along the Alger County beaches east of Munising by Wednesday afternoon and evening. With upper low lingering over Lake Superior on Wednesday, a few instability showers and isolated thunderstorms will linger into the afternoon hours before noticeable drying and surface ridging begins building in late in the day.
Water vapor imagery this morning features a vigorous upper trough over eastern Montana ejecting eastward across the northern Great Plains. A stout mid/upper ridge centered over the Four Corners region is helping steer the aforementioned trough across the northern tier of the CONUS, leaving us with heat and dry conditions as the main headlines. With the "cool" front being past the area for tomorrow, slightly cooler (but still above normal) temperatures are forecast to range from 89 to 95 degrees with clear skies.
423 AM EDT Tue Jul 19 2022 The quasistationary upper-level pattern continues with ridging in the west and troughing over the eastern US.
As the warm front of an approaching low continues to move into the area early this morning, expect shower and thunderstorm activity to dwindle, as convective debris and a strengthening cap near the sfc with time should limit convective development. As surface and upper low along with accompanying surface cold front move across the Upper Lakes/U. Northwesterly winds behind the low will yield dangerous swimming conditions along the Alger County beaches east of Munising by Wednesday afternoon and evening. With upper low lingering over Lake Superior on Wednesday, a few instability showers and isolated thunderstorms will linger into the afternoon hours before noticeable drying and surface ridging begins building in late in the day.
We remain under the influence of a 596dam upper level high spinning over the Four Corners area. Skies, sunny now, will remain clear overnight as temps slip into the low 70s. Any alterations of the forecast that push HI a little warmer (slower front?) may necessitate the inclusion of the Lincoln or Omaha metros. Return flow helps allow the ridge build back over the area for the end of the week and into the weekend.
Upper trough will continue moving eastward today, keeping precip chances confined mainly to the south and east during the day, and even linger into the overnight hours for the east.
Upper high was centered near the Four Corners with a potent low over northern Idaho. The upper low makes steady east progress tonight into Tuesday night, reaching the Great Lakes by dawn Wednesday. South to southwest low- level flow locally will increase tonight into Tuesday, with winds speeds above the shallow boundary layer enough to prevent another night of patchy fog, but will usher in warmer air, with 850 mb temps 4-5 C warmer than today. The post-frontal airmass is only marginally cooler though many locations should see dewpoints back into the 50s and keep heat indices below triple digits.
A 500-mb ridge over the Four Corners regions strengthens and heights will rise locally during this time period. Morning lows will be seasonable, high temperatures on Tuesday will be a few degrees warmer than today; just shy of 90. The low's center tracks through northern Michigan, thus we are a bit removed from the best forcing too. However, later in the day Wednesday, a cold front associated with this feature sweeps through and provides an improved opportunity for thunderstorms.
The robust high pressure system centered in the central Atlantic Ocean will continue to dominate our sensible weather as it builds and move westward.
1252 AM EDT Tue Jul 19 2022 A trough will linger near the area through Wednesday.
216 AM MDT Tue Jul 19 2022 Upper low will move east out of the region this morning. Gusty west to NW winds will continue today with the strongest winds expected this morning with enough of a chance of a 60 mph gust in the south to keep the High Wind Warning in effect for now. Temperatures will be cooler today with highs mainly in the 80s.
A strong upper level cut-off ridge is locked in place over the Southern Rockies/Desert Southwest, as per recent RAP analysis. Tuesday night, as the upper level impulse continues to dig into the upper Midwest/Great Lakes, the upper level cut-off ridge will be forced to retrograde just enough to allow a stronger push of cold air into southwest KS. Unfortunately, this albeit small relief will not survive more than a day, as the upper level cut-off ridge builds back eastward and fosters a return of triple digit highs through at least the end of the week.
SHORT TERM (Now through Wednesday): The persistent mid-level ridge of high pressure still sits across the Desert SW, with only a slight weakness aloft along the lower Texas coast.
This additional development is in response to the upper trough axis swinging into and across the area. Chattanooga Airport, TN 87 72 93 75 94 / 50 40 40 50 50 Knoxville McGhee Tyson Airport, TN 87 71 91 74 93 / 30 20 40 50 40 Oak Ridge, TN 87 71 91 73 92 / 30 20 30 50 40 Tri Cities Airport, TN 83 67 88 70 88 / 20 20 30 50 40.
No precipitation is expected with this system, however, some slightly cooler temperatures can be expected behind the trough. Cooler air will mainly affect northern Nebraska where highs are only expected to rise into the low 90s. Across the south, it will take some time for the cooler air to reach this area leading to highs still in the upper 90s to low 100s. Despite this, gusty northwest winds up to 25 to 30 mph associated with the trough will keep heat indices only in the mid 90s. With the passage of the trough, temperatures drop into the mid to upper 90s across the region for Wednesday.
1113 PM EDT Mon Jul 18 2022 Warm, humid, and dry weather will resume tonight, and will be interrupted by the approach of another cold front on Wednesday. Great Lakes ridging will result in a dry and sunny Tuesday, with seasonable temperature. Warm and moist advection will continue with swly flow through Wednesday, prior to the peripheral passing of low pressure in the northern Great Lakes that will lend a frontal passage and provide precipitation chance. High pressure wl return genl VFR to area terminals this evening, but llvl moisture beneath a subsidence inversion should support areas of MVFR/IFR fog development after midnight, continuing through early Tues. The next chc for genl restrictions is expected with a late- Wednesday cold front.
[Key Message] * Heat indices in the mid 90s to near 100 today Today and tonight, high pressure will slide southeast as a cold front moves into central IA today and across the CWA this evening and overnight. If there is more mixing, they may be a bit warmer, but with dry air aloft dew points may lower.
A lot will depend on how the low level thermal and wind fields shake out.
Taking a look at the upper level pattern, we can see a large ridge centered over the four corners, stretching north into the northern Plains/Midwest, with a trough over the eastern U. This ridge will nose more into our area Tuesday, resulting in the hottest temperatures of the year so far. Highs tomorrow are forecast to be in the low to mid 90s north of the MO River and in the upper 90s to around 100 degrees along and south of the MO River. Tuesday evening a trough will move east across the northern Midwest, lowering 500 mb heights and sending a cold front through our area. Heat indices will range from the low 90s to upper 90s. As previously mentioned, only slightly cooler for Wednesday.
A weak cold front will bring a chance of precipitation to the area on Wednesday night, with marginally cooler temps following. On Wednesday, a low pressure system will begin to dig across the Upper Great Lakes. By late Wednesday, medium-range consensus suggests the aforementioned low will shift from Ontario into Quebec with an attendant cold front extending southward through the Great Lakes and into the Ohio Valley.
439 AM EDT Tue Jul 19 2022 Southerly flow will bring warmer air to the region for Tuesday into Wednesday.
Despite the lower dewpoints, heat indices off 100 to 105 are still likely for portions of the area. high pressure continues to dominate the Desert Southwest and the the Southern/Central Plains.