Aikyam-Lab/Synoptic-Bench huggingface dataset:
Prevailing westerly flow continues with the region situated between high pressure ridging over south FL and a gradually advancing frontal boundary across the SE US.
(Rest of Today) Morning analysis suggests that a region of weak (5-15 knot) cyclonic flow aloft remains situated across the TN Valley, between two distinct 500-mb anticyclones centered across southwestern TX/southern NM/northern Mexico and across the Atlantic waters to the east of the Bahamas. With persistent mid- level cloudiness likely to result in temps a couple of degrees cooler this afternoon (85-90F range), MLCAPE should only reach 1500-2500 J/kg, with storm impacts expected to be similar to those from yesterday (brief strong winds of 40-50 MPH, small hail and lightning).
1237 PM CDT Fri Jul 7 2023 (Today and tonight) The upper-level ridge will slightly weaken, but remain steadfast over the area today causing continued hot and dry conditions across West Central Texas. Slightly above-normal afternoon highs are expected to reach into the 90s today, with overnight lows only falling into the lower to mid 70s.
An upper level trough remains over NE CA and NW NV today. Isolated afternoon/evening thunderstorms over the higher terrain each day with gusty winds and blowing dust possible.
Temperatures this afternoon across the island chain has reached into the lower to mid 90s with dew points in the mid to upper 80s. Low level ridge axis lies just to our south across the Straits of Florida, which has kept us under a light southwesterly flow. The aforementioned low level ridge axis will slowly lift northward over the weekend.
Cliff PREVIOUS DISCUSSION: An upper ridge will be building eastward through the weekend bringing generally dry weather and warming temperatures to northeast Montana. With the slight unstable northwest flow across Montana today, there is potential for a few random showers or thunderstorms to pop up, generally across the higher terrain of central Montana, but could be further east. As the ridge builds east, the convective potential will diminish.
At upper levels, a weak ridging in place while the low-level ridge axis remains to the south/east of the state.
748 PM EDT Fri Jul 7 2023 (Through Saturday) Subtropical ridging continues to influence our weather to begin the weekend via diurnally driven convection and hot/muggy conditions. Looking at temperatures, morning lows in the 70s give way to peak readings in the low/mid 90s by the afternoon.
655 PM CDT Fri Jul 7 2023 A trough is positioned from Hudson Bay to Nebraska while high pressure is situated to the south and west.
721 PM EDT Fri Jul 7 2023 (Rest of today through Saturday) A trough of low pressure over the eastern United States has evicted deep-layered high pressure back over the Atlantic.
805 PM EDT Fri Jul 7 2023 Warmer and more humid air returns along with rain and storm chances this weekend.
The weather pattern should remain in place ridge axis stays over south Florida and the Straits. Model guidance continues to not be consistent with the timing of the showers and storms, but the bottom line is that there is a non zero chance of showers early with the highest chances expected in the afternoon. High pressure in place will keep westerly flow and moist airmass across the Gulf waters.
Once again, daytime high temperatures soared to the lower 90s in the Lower and Upper Keys, while the Middle Keys reached the mid 90s.
A warm front will move northeast across the FA through this evening with more humid conditions. The main concern then becomes Saturday as an influx in theta-e occurs behind the aformentioned warm front causing dewpoints to surge into the low to mid 70s.
A weak upper level trough just off the coast will continue to bring relatively cool temperatures through the weekend. Just enough instability is present east of the trough near Lassen Park and far eastern Shasta County for very isolated showers and thunderstorms this afternoon.
907 PM EDT Fri Jul 7 2023 A weak cold front will stall out across the area tonight and into the weekend.
547 PM MDT Fri Jul 7 2023 Long wave western NOAM ridge will slowly shift east and breakdown as the central Canadian upper trough remains in place.
Another round of high-based thunderstorms will develop on Saturday afternoon over the high terrain. A few storms could move into the lower valleys Saturday evening for gusty winds.
956 PM CDT Fri Jul 7 2023 (Issued 956 PM CDT Fri Jul 7 2023) Isolated to widely scattered light showers continue to develop in a low level warm air advection regime ahead of an incoming weak area of low pressure. Following the rain, weak high pressure should move in, allowing for some breaks in the clouds.
Model guidance continues to not be consistent with the timing of the showers and storms, but the bottom line is that there is a non zero chance of showers early with the highest chances expected in the afternoon. At upper levels, a weak ridging in place while the low-level ridge axis remains to the south/east of the state.
Key Points: - Cold front moves through this evening and overnight, with a few strong to severe storms still possible along the front this evening. Farther to the northwest, a cold front is located across central Nebraska. As this front moves southeast this afternoon and evening, showers and thunderstorms will continue to develop, with the highest coverage near the intersection of the front and the outflow boundary. The widespread clouds and cooler temperatures will tend to limit instability to 1500-2000 J/kg, but with around 35-40 kts of generally unidirectional shear a few storms could be on the stronger side.
/NEW/ /Through Saturday Night/ North and Central Texas will remain beneath the eastern edge of a mid level ridge currently centered over West Texas. The ridge will be weakened along its northeast flank over the next few days as an upper trough deepens over the Deep South. The ridge will likely hold strong this evening, as it appears that subsidence has shut down any convective attempts thus far.
A tongue of low level thetae with an associated surface warm front will then extend northward favoring sections of central Lower Michigan after 12Z Saturday. Some competing interests in the quality of warm advection/thermal gradients as a convective induced low pressure will augment southerly flow during the early part of the day, within a greater large scale support for southeasterly surface winds. This results in a longer wavelength trough over western Mi Sat afternoon which would produce better moisture and instability transport into Se Mi.
With temperatures warming into the 70s to lower 80s, instability is expected to increase over the Tri-State area while the higher mid- level lapse rates move north over the area. Tomorrow, the upper ridge is expected to amplify over the Western CONUS while the upper trough cross the Mississippi River Basin.
1024 PM EDT Fri Jul 7 2023 High pressure over the Ohio Valley tonight will move east as a cold front approaches from the west. This cold front will stall along the I-71 corridor Saturday evening, sparking shower and thunderstorm activity. Moisture to increase ahead of an associated cold front approaching from the west with moderate instability developing Saturday afternoon. The highest threat looks to be across the west during the afternoon into the early evening. Weak surface wave to pivot ne thru the Great Lakes with associated cold front dropping into ILN/s area late Saturday night. Low temperatures to range from the lower 60s northwest to the mid/upper 60s southeast.
Afternoon temperatures above 110 degrees at the lowest elevations of the Grand Canyon will continue to dictate an Excessive Heat Warning for that area.
616 PM EDT Fri Jul 7 2023 A weak cold front will stall out across the area tonight and into the weekend.
726 PM EDT Fri Jul 7 2023 Prevailing westerly flow continues with the region situated between high pressure ridging over south FL and a gradually advancing frontal boundary across the SE US.
401 PM CDT Fri Jul 7 2023 A trough is positioned from Hudson Bay to Nebraska while high pressure is situated to the south and west.
(Today and tonight) Hot and dry conditions are expected for today as the upper-level ridge begins to strengthen across West Central Texas into Sunday. Slightly warmer high temperatures are expected today in the mid 90s to near 100, with overnight lows remaining in the mid 70s.
Decided to issue a heat advisory for Saturday and Sunday for the Lower Columbia Basin of Washington.
However, with PWATs reaching close to 2 inches in some spots and freezing levels near 14,000 feet, efficient rainfall rates are likely with any stronger cells.
With upper level high pressure largely in control, afternoon highs should have no problem reaching the middle to around 100. The only exception will be across the northeast where clouds and some precipitation should hold highs to the lower 90s. Shower and thunderstorm chances will increase slightly across the northern zones Saturday as a weak cold front approaches from the Central Plains. The Red River counties will have the best chances of seeing some precipitation during the day but even locations as far south as the I-20 corridor could see scattered showers and storms, especially during the evening and overnight once the cold front eases its way southward.
While temperatures will be warmer and likely in the low to mid 80s, dewpoints will remain in the mid to upper 50s. Upper ridging will build over the western CONUS. While the pattern does favor warmer weather, with stronger upper-level northwesterly flow moving over the area, there is a decent chance for one or more convective complexes to affect the area.
Saturday should be a bit warmer than today as a ridge begins developing over the Western US. The aforementioned ridge sets up over WY on Sunday, with warming temps and mostly dry conditions through the rest of the week.
Currently, the remnant overnight MCS has exited the area off to the east, with a cold front stretching from near Colby, Kansas, to Albion, Nebraska. Behind the front, winds were breezy from the north and temperatures ranged from the low 70s to near 80 degrees across central and western Nebraska. This will also promote another below average morning temperature wise, with lows falling into the low to middle 50s. An additional round of scattered thunderstorms is possible Saturday afternoon, as broad upslope flow helps to initiate convection across the high terrain in eastern WY and the western NE Panhandle.
124 AM EDT Sat Jul 8 2023 Dry and warm today as high pressure drifts across the region. A complex of showers and storms likely develops to our west late today, supported by the advancing trough aloft and its associated cold front. Redevelopment is possible later Sunday afternoon as the upper trough approaches and we see an enhancement in large-scale forcing. The upper trough pushes off to the east Sunday night and rain chances quickly taper off from west to east as a result.
Main upper trough axis and associated cold front will shift southeastward through Middle Tennessee on Sunday into Sunday night, bringing another round of showers and storms to the area.
(Today and tonight) Upper level ridging remains centered over northern Mexico early this morning with west-northwesterly flow aloft continuing over much of the central CONUS.
We shouldn't completely clear out behind the trough as diabatic heating should allow surface temperatures to reach their convective temperatures, generating a diurnal cumulus field. This cloud field will dissipate by the early evening, leading to mostly clear skies and calm conditions tonight as an area of high pressure builds back into the region. Highs in the low 80s and humidity values in the 40s and 30s.
Some competing interests in the quality of warm advection/thermal gradients as a convective induced low pressure will augment southerly flow during the early part of the day, within a greater large scale support for southeasterly surface winds. This results in a longer wavelength trough over western Mi Sat afternoon which would produce better moisture and instability transport into Se Mi.
Overall, warmer and drier conditions can be expected over the area on Sunday as an upper ridge builds over the region.
Highs today will be warmest to the west, with highs in the low 80s, while readings across the east will top out in the upper 70s. Light winds and warming temperatures are expected for Sunday, with highs in the low to mid 80s.
(Today through Sunday) 500mb ridge is slowly building eastward with the center expected to remain over West Texas and Desert SW Sunday. Temperatures begin to increase once again with more sun, the building ridge and the obvious minimal to no rain coverage.
The appearance on water vapor coupled with GFS/ECMWF evolution of the upper trough makes me think this convection may persist for the next few hours and that convection in general will be faster to move west to east through the day than the HRRR indicates. Redevelopment in the soupy airmass and along the front is likely in a few places, but large scale ascent should switch to more negative by 18-21z today given the upper trough placement and the shutting off of any warm air/moisture advection. Locally heavy rain will remain a threat through the day and a near-term flash flooding threat definitely exists in the Ozark foothills of SEMO, but more rapid forward motion should begin in 3-6 hours as the upper trough gets closer.
(Saturday through Sunday night) Global models continue to suggest that a broad upper cyclone will drift southward across southern Canada (to the west of Hudson Bay) during the period from Saturday-Sunday, supporting a gradual increase in westerly flow aloft across the TN Valley. Additional but smaller clusters of convection may impact the region for much of the morning hours on Sunday, which could originate both along trailing outflow from the initial MCS as well as along a cold front that will begin to shift southeastward from the Lower OH Valley. Although deep-layer flow/shear will continue to gradually strengthen (peaking in intensity Sunday afternoon and evening), the degree of storm intensity and coverage during this period (as the cold front drops southward into our CWFA) will be highly dependent on cloud cover and instability across our region.
This flow will also prevail across the higher terrain of Colorado. The highest chance of storms will be along and west of Highway 83 today and tonight. As stated earlier, storms should form across the higher terrain of Colorado then slowly drift across the western zones this afternoon and evening. Have the highest confidence of storms along the Colorado and Oklahoma border for far southwest Kansas. What a marvelous day across southwest Kansas considering it's July and those highs would be way worse (aka hotter) than forecast! For Sunday, a drier forecast is expected as storm chances look fairly unlikely due to weak upper level ridging across the Rockies and out over the central plains.
1030 PM MDT Fri Jul 7 2023 Long wave western NOAM ridge will slowly shift east and breakdown as the central Canadian upper trough remains in place.
Surface analysis this morning shows a weak cold front from west central MN up to Lake Superior. In fact, this favoring areas north of the MPX area looks to continue into Sunday as a cold front comes across the international border. As for temperatures, today will be another day of below normal temperatures, with highs comfortably remaining in the 70s, but on Sunday, increasing southwest winds will usher in warmer air and temperatures warming back to near normal, which is in the low to mid 80s.
An upper level low is digging into the western Great Lakes early this morning. Thunderstorms are ongoing on the leading edge of the trough and continue to grow upscale. Based on the high resolution guidance, confidence on that scenario is low. Cooler air filters in behind a cold front such that lows will be in the upper 50s to near 60. After a dry start to the week, a blocking pattern over North America directs several disturbances through the Midwest bringing us numerous chances for wet weather.
1210 AM CDT Sat Jul 8 2023 (This evening through Sunday) Arkansas will remain along the northeast periphery of H500 ridging centered over the SW US through the period.
254 AM EDT Sat Jul 8 2023 After a quiet and mostly dry start to the day, showers and storms will begin to ramp up quickly by late morning or early afternoon as a pre-frontal trough approaches from the west. synoptically there is a Quasi Omega blocking pattern, with a SW herculean high over Land of Enchantment to AZ and a highly anomalous low (3 SD below climo) over N Manitoba and low along British Columbia coast. As the upper level trough axis is slow to push out. Trough axis should sweep through by Sunday evening. As the trough swings through Sunday night, dew pts will go from the upper 60s and low 70s, down into the lower to mid 60s by daybreak. Cool Canadian high pressure dominating the surface pattern with NW flow aloft.
137 AM PDT Sat Jul 8 2023 Temperatures will be cooler this weekend, ranging from 3 to 5 degrees below normal for July.
A large dome of high pressure is currently centered over the Southern Plains, West Texas, New Mexico, and into Chihuahua Mexico.
Key Points: - Cold front moves through this evening and overnight, with a few strong to severe storms still possible along the front this evening. Farther to the northwest, a cold front is located across central Nebraska. As this front moves southeast this afternoon and evening, showers and thunderstorms will continue to develop, with the highest coverage near the intersection of the front and the outflow boundary. The widespread clouds and cooler temperatures will tend to limit instability to 1500-2000 J/kg, but with around 35-40 kts of generally unidirectional shear a few storms could be on the stronger side. Sunday morning lows should drop into the upper 50s as high pressure moves overhead. Expecting most of the weekend to be dry, given surface ridging nearby and the boundary well to our south.
355 AM EDT Sat Jul 8 2023 Dry and warm today as high pressure drifts across the region. A area of showers and storms will likely move into far western counties this evening, supported by the advancing trough aloft and its associated cold front. Redevelopment is possible later Sunday afternoon as the upper trough approaches and we see an enhancement in large-scale forcing. The upper trough pushes off to the east Sunday night and rain chances quickly taper off from west to east as a result.
This high will be directly overhead this afternoon, leading to light winds and mostly clear skies. A southerly and then southwesterly return flow sets up Saturday night into Sunday, and resulting WAA will lead to increasing temperatures with highs in the 80s by Sunday afternoon, ~10 degrees warmer than the day before.
1157 PM CDT Fri Jul 7 2023 A warm front will move northeast across the FA through this evening with more humid conditions. The main concern then becomes Saturday as an influx in theta-e occurs behind the aformentioned warm front causing dewpoints to surge into the low to mid 70s. With that said, a cold front will sweep across the Ohio Valley Saturday night providing quick relief from the humidity as dewpoints return to the lower 60s on Sunday.
Ensemble guidance still advertising an expansive subtropical ridge will encompass an area from California to Texas by the end of next.
There is a also a drastic temperature difference with areas in the clearing about 10 degrees warmer. Saturday and Sunday: Weak mid-level ridging will build over the weekend and there will be weak flow at the surface. This will lead to a couple of pleasant days with mostly clear skies and temperatures in the high 70s on Saturday and lower 80s on Sunday.
(Today through Sunday Night ) West-northwesterly flow will prevail aloft over AR through the period between strong high pressure centered over the southwest US and broad low pressure over the Upper Midwest/Great Lakes region. For tonight, convective activity over eastern OK/northwest AR will be enhanced by a weak cold front dropping south into the area from KS/MO. Mostly cloudy and noticeably cooler conditions with widespread light to moderate precipitation are on tap for Sunday as the cold front stalls somewhere over central to south central AR. Highs Sunday afternoon will range from the lower 70s over the northern higher terrain to the lower 80sover the far south.
The majority of the storms will be over the mountains, but a few storms will move out over the lower elevations.
240 AM MDT Sat Jul 8 2023 Current surface analysis shows weakening cool front pushing south into the area, with high pressure centered to the north of the region. Upper level analysis shows large low over the Hudson Bay region, with weak ridging over the Great Basin region. A somewhat drier pattern can be expected over the next few days as ridge to the west gradually moves over the Rockies.
As high pressure gradually builds in from the desert southwest, dry air will continue its northerly advance through central and into northern NV. As a result, temperatures will climb another degree or two with afternoon highs in most valley locations in the low to mid 90s.
139 AM EDT Sat Jul 8 2023 High pressure over the Ohio Valley tonight will move east as a cold front approaches from the west. This cold front will stall along the I-71 corridor Saturday evening, sparking shower and thunderstorm activity. Moisture to increase ahead of an associated cold front approaching from the west with moderate instability developing Saturday afternoon. The highest threat looks to be across the west during the afternoon into the early evening. Weak surface wave to pivot ne thru the Great Lakes with associated cold front dropping into ILN/s area late Saturday night. Low temperatures to range from the lower 60s northwest to the mid/upper 60s southeast. Maximum temperatures will be roughly five degrees below normal Sunday due to the cold front but will quickly rebound as the work week begins.
107 AM EDT Sat Jul 8 2023 High pressure early today. A cold front brings more unsettled weather late Saturday through Sunday. High pressure crosses during the first half of the work week. A high pressure system early today will provide for dry weather. Moisture in advance of a cold front will push into the area later today and Saturday night, providing for a chance of showers and thunderstorms. The cold front will then push into the area early Sunday, increasing the chances for precipitation.
335 AM EDT Sat Jul 8 2023 (Today through Sunday) A trough of low pressure over the eastern United States has evicted deep-layered high pressure back over the Atlantic. With warmer air aloft leading to poor lapse rates, shower and thunderstorm activity should be limited to the garden variety.
Regarding the marginal risk for severe storms across eastern IL on Saturday, the potential hinges on the timing of the cold front. Erwin The remnants of an MCS that formed over the High Plains late last night continues to track toward the Mississippi River. While the airmass further east across central Illinois is dry/subsident beneath prevailing high pressure, radar loops suggest showers will spill into the Illinois River Valley over the next 2-3 hours. with attention then turning to potential convective re-development along an advancing cold front during the afternoon.
1253 AM EDT Sat Jul 8 2023 A weak cold front will stall out across the area tonight and into the weekend.
Temperatures are hovering in the lower to mid 80s, combining with dewpoints in the mid to upper 70s to produce heat indices well above 90 degrees at 4 AM. Surface analysis has changed little during the past 24 hours, depicting the subtropical high over the central Atlantic and a weak ridge extending westward through the northern Bahamas and the Keys. Aloft, the typical midsummer subtropical ridge is centered just east of the Bahamas, with a ridge extending westward across the Gulf of Mexico. The hot and dry SAL regime will continue to dominate our weather pattern through the next few days, as the low level ridge slowly inches northward from the Keys into South Florida, allowing the dry SAL airmass to linger over our area for an extended time period.