Aikyam-Lab/Synoptic-Bench huggingface dataset:
Subjective surface analysis indicates that a cold front was moving southeast across central Arkansas at the time of this discussion. Overall storms are not expected to become more organized this afternoon as most storms were elevated behind the cold front, but locally strong to damaging winds are the primary threat associated with any storm that develops this afternoon into this evening. This is the primary driver of the cold front moving across the state at this time. This cold front will usher in cooler temperatures, but more importantly, much drier air into the region. Upper level ridging will remain centered over the southern CONUS Rockies, but the ridge's influence will spread east over the great plans and over Arkansas for the remainder of this work week.
It's a beautiful day out there this afternoon with highs in the upper 70s and dewpoints in the low 50s a welcome reprieve compared to the heat and humidity of last week. Similar conditions are expected tomorrow as the high remains centered over the region, but a streamer of vorticity pivoting around an upper level low well to our northeast may generate enough lift to kick off some isolated to scattered showers and thunderstorms across western Wisconsin late tomorrow afternoon evening. Temperatures trend warmer towards the end of the week and into the weekend as the western ridge noses east into the central US and eventually flattens out over the weekend.
/issued 848 PM CDT Mon Jul 22 2019/ A cold front continues to push through the Mid-South this evening. /issued 258 PM CDT Mon Jul 22 2019/ Surface cold front had dropped to the I-40 corridor of west TN at 2 PM CDT / 19Z.
This is thanks to a change in the upper level pattern, which now sees the ridge retrograded back to the western U. and a deep longwave trough in the east.
1045 PM MDT Mon Jul 22 2019 PAC NW trough re-loading will continue through mid week, supporting downstream ridging over the Rockies.
346 AM CDT Tue Jul 23 2019 High pressure building into the middle of the country this morning, with northwesterly flow aloft established over the Plains and into the Midwestern states. Have warmed a degree or so over blended MOS as this morning is also a little warmer than 24 hrs ago.
314 AM CDT Tue Jul 23 2019 We will start the period with a large area of high pressure centered over the 4-corners area, with a ridge stretching north across MT, Alberta, and Saskatchewan. At the surface, the 1026mb high over eastern NE still had a ridge extending up across our entire area as well as much of ND and western MN.
High pressure will be displaced to our south and east tonight and Tuesday resulting in a prolonged period of west to southwest winds. A weak cold front will reach the northern Gulf Tuesday night or Wednesday, bringing enhanced westerly winds and numerous showers and storms offshore the Nature Coast.
Otherwise, look for a dry and cooler forecast today and tonight.
/issued 302 PM EDT Mon Jul 22 2019/ Our attention is focused on an area of low pressure now over the western Bahamas. The core of this low pressure system is forecast to remain offshore and to our east, bringing increased shower and thunderstorm coverage from tonight into tomorrow, particularly across our eastern areas. Enhanced rain chances may continue into Wednesday, particularly across northern portions of our area as deep moisture associated with the low pressure system pulls away.
Wednesday will begin to warm up as we lose the upslope flow and influence of our cold front, but the warming won't be as rapid as we usually see this time of year.
Over the next several days, our region will lie between an elongated area of low pressure along North Florida and the adjacent Atlantic and Gulf waters and high pressure along the north coast of the island of Cuba and the Straits of Florida.
Dew points will remain in the mid-upper 50s most areas, with highs again in the upper 70s-lower 80s, similar to, or perhaps a degree or two warmer than yesterday. The ridge will linger in our east tonight, while western areas begin to see some southerly return flow. This southerly flow will begin to draw warmer, and slightly more humid air back into the region. Mid-level wave moving into the western Dakotas begins to flatten the ridge Wednesday afternoon/evening, and decent shot of warm advection ahead of the wave could produce some elevated showers or storms in western parts of the region Wednesday night.
45 interior dew points falling into the upper 50s (north) to middle 60s (coastal) will make it feel like October in July! Mornings is when this unseasonable air mass will be most felt as minimum temperature readings fall into the lower to middle 60s (rural) to around 70 in more urbanized areas.
/issued 231 PM CDT Mon Jul 22 2019/ Highly amplified upper flow remains established over the lower 48 with an upper trough in the eastern Conus and a stout upper ridge centered to our west near the 4 Corners region and central Rockies. Surface dewpoints will fall into the lower to mid 50s Tue afternoon. The upper high strengthens to 596 dm by midweek with rising heights again over West Texas under northerly flow aloft. Precipitation will likely remain in northern Mexico into the Gulf along the frontal system, and underneath the high in the higher elevations of the central Rockies.
1040 PM CDT Mon Jul 22 2019 Pleasant conditions in place across the area this afternoon with high pressure building in from the Northern Plains. High pressure builds in west of the Mississippi River tonight into Tuesday, keeping us in northerly surface flow. A weak mid-level trough/pv-advection drops southeast through portions of eastern/central WI Tuesday afternoon. High pressure continues to build overhead with lighter winds at the surface Tuesday Night which may lead to some valley fog. A bit warmer but remaining dry on Wednesday as amplification of the mid-level ridge drifts across the region and low level warm advection kicks in.
Current satellite imagery shows a lower stratus deck moving southward across the mid Mississippi Valley behind a cold front, so expect cloudy conditions to persist through the overnight hours. The cold front currently stretching from Corinth, MS to Nashville, TN is expected to enter northwest Alabama by midnight and will continue tracking east across the Valley overnight. Lingering shower activity should dissipate tomorrow morning as drier air pushes in behind the front and the upper level trough axis envelops the East Coast. Stronger cold air advection will push into the region as a high pressure system begins to slide into the Ohio Valley from the Northern Plains. Clear skies and high temperatures in the low 80s will make for an abnormally pleasant late July day.
Skies will be clear and winds light, with lows dropping into the lower to mid 50s. Skies should be mostly sunny with highs a few degrees warmer than today. Upper level high pressure will be established across the four corners and desert southwest midweek through the weekend. Our area will be located on the northeast side of the ridging with northwest flow aloft. VFR anticipated for all terminals through the forecast period as ridging build to the west.
A cool pool over the mountains allowed storms to linger further onto the lower plains, proceeding just past Billings and containing an outflow boundary with winds up to 40 mph. As a cold pool formed over the mountains yesterday to help push storms further into the lower plains than anticipated, the same is expected to occur today, with storms likely reaching Billings and chances for them to head further east. Northwesterly winds up to 30 mph look to impact areas at, north, and west of Billings with this mixed atmosphere, and could be amplified by another round of storms off the mountains in the afternoon and evening, as well as a cold front.
Quiet and dry conditions continue as the upper ridge axis builds over the Rockies and slowly moves east into the Plains mid-week. Some afternoon cumulus clouds but that will not impact temps too much and we should still get into the low to mid 80s this afternoon. With the ridge axis shifting further east there will be plenty of warm air in the area along with good mixing and we should see temps in the mid to upper 80s.
228 AM CDT Tue Jul 23 2019 The center of the upper level ridge will be over southern Colorado or northern New Mexico through Wednesday night.
A breezy northerly flow in an upper trough over the region will result in drier, cooler conditions for the rest of today. Updated at 325 AM EDT Tue Jul 23 2019 Cooler weather will stretch into the midweek period. Wednesday starts off with an upper trough positioned over the Ohio Valley. The upper trough axis slides across the Appalachians during the daytime, and heights aloft gradually rise through the remainder of the work week.
High pressure will continue to sink SE through the day today. High pressure will shift off to the east and weak lee troughing will resume across the High Plains.
247 AM CDT Tue Jul 23 2019 With amplified upper ridge axis centered over Rockies, area remains in northwest flow. Watching short wave trough drop across western Great Lakes early this morning that triggered some clouds and convection, but that should continue to exit the area. Later periods can be summarized by flow becoming somewhat more zonal and series of short wave troughs passing through creating occasional rain and storm threats.
1242 AM CDT Tue Jul 23 2019 221 PM CDT High pressure situated across the Plains will continue to build across the region through the period, but with the CWA remaining on the eastern edge of this high.
155 AM MDT Tue Jul 23 2019 Water vapor shows upper ridge axis through the northern Rockies with some embedded monsoonal moisture. At the surface, ridge is located over the eastern Dakotas with lee trof from central MT through central WY. A bit of mid/high clouds tracking through the ridge into the forecast area. Another dry day in store with large scale subsidence in place from the upper ridge. Wednesday will likely be the hottest and most humid day of the week with thermal ridge overhead. Many plains locations will rise into the lower 90s. Could see some late day storms as the approaching trof works into our western zones while Pac NW trof moves into the Rockies.
1057 PM CDT Mon Jul 22 2019 High pressure centered over the northern Plains will drop southeast through Tuesday and Tuesday night. Northerly flow on the eastern side of this high will bring cooler and drier air into the mid Mississippi Valley through the short term. The high should keep a mostly sunny sky over the forecast area on Tuesday. It should be another clear and cool night on Tuesday night as the high settles into western Missouri with similar temperatures as tonight in the mid 50s to low 60s. Carney The high will drift slowly east through the end of the week.
328 AM CDT Tue Jul 23 2019 Today and Tonight: While the pre-frontal trough has cleared the forecast area this morning, actual cold front was poised to enter the northwest corner prior to dawn. Drier/cooler air will be deepest over northern portions by late afternoon and it is here where decoupling will be most efficient.
123 AM MDT Tue Jul 23 2019 Modest N-NNW flow aloft will prevail over the Tri-State area -- on the eastern periphery of a pronounced upper level ridge over the Rockies. Wed-Sat: Modest NW-NNW flow aloft will prevail over the Tri-State area, on the ENE-NE periphery of an upper level ridge situated over the Rockies. Sun-Tue: GFS/ECMWF guidance indicate that the upper level ridge over the Rockies will de-amplify/flatten this weekend, placing the Tri-State area in closer proximity to the mid-latitude westerlies.
Ridging aloft and at the surface will continue to support a dry airmass through Tuesday night. Will start the period under the influence of upper ridging ahead of a wave approaching from the Pacific Northwest. At the surface, high pressure moving east will result in return flow, increasing heat and low level humidity.
257 AM EDT Tue Jul 23 2019 High pressure influences brings cooler, drier weather through midweek. Despite the cold front clearing the mountains, it could take some time to completely eliminate the lower level moisture in the mountains. Cooler day and lower dewpoints all around today. Sky largely clears tonight, and will get some radiational cooling in the valleys/hollows, with most all locations in the 50s or cooler by the morning. Drier and cooler weather to start the short term period with upper trough located across the area. Heights will gradually start to build across the area towards the end of the short term period, with gradually warmer and humid conditions starting to take over again. Upper ridging will continue to develop across the eastern U.
904 AM EDT Tue Jul 23 2019 High pressure will provide for dry conditions and somewhat cooler than normal temperatures through mid week. High pressure will allow for dry conditions across the region today.
632 AM EDT Tue Jul 23 2019 High pressure will provide for dry conditions and somewhat cooler than normal temperatures through mid week.
527 AM MDT Tue Jul 23 2019 Upper-level ridging will quickly build into the region today w/ H5 heights climbing to 594-596 dam by 00z Wednesday. Considerably warmer today, with high temperatures in the 80s for much of the CWA. A flattening ridge is expected to give way to fairly active quasi- zonal flow on the northern periphery. Thunderstorms are possible each afternoon & evening across portions of southeast Wyoming and the western Nebraska Panhandle, w/the best chance over the higher terrain.
Flow is still relatively light over the lowest 3 kilometers. /issued 327 AM EDT Tue Jul 23 2019/ A mid level trough centered over eastern Canada extending into the southeastern US will slowly rotate through the eastern seaboard today and Wednesday.
644 AM CDT Tue Jul 23 2019 Northwest upper level flow has taken hold over the region and will remain in control as a large ridge becomes entrenched across the western CONUS.
Expect warmer temperatures today with highs in the 80s. Instability creeps back into the forecast this afternoon as southerly return flow increases, but very warm and dry conditions in the lower layers of the atmosphere should inhibit any convection. Regarding storm mode: deep layer shear vectors are forecast to be perpendicular to the trough, suggesting the potential for discrete supercells with any storms that can mature. With that said, severe weather certainly looks possible and the Storm Prediction Center has placed areas along and west of the highway 83 corridor in a marginal risk of severe weather in the latest Day Two Convective Outlook.
The main affect for the area will be a slowing of the eradication of the cloud cover, increased afternoon CU and a chance for showers over the SE ridges, with showers dissipating with the loss of daytime heating. The area will remain under the influence of the trough on Wednesday. This should promote at least scattered CU on Wednesday, with a weak disturbance within the trough potentially creating isolated rain showers across the ridges.
1100 AM EDT Tue Jul 23 2019 Dry air continues to advect into the region along the upper trough axis and behind the surface front, per latest GOES WV imagery. Chattanooga Airport, TN 82 62 83 62 / 40 0 0 0 Knoxville McGhee Tyson Airport, TN 78 59 80 60 / 70 0 0 0 Oak Ridge, TN 79 60 82 61 / 60 0 0 0 Tri Cities Airport, TN 76 55 78 56 / 80 0 0 0.
/Issued 451 AM EDT Tue Jul 23 2019/ Focus for the short term continues to be a slow moving cold front that will move through the state today. Amplifying trough over the eastern U. Pops quickly taper off from the northwest behind the front as dry, cooler air filter in to the state. Highs today will be unseasonably cool today due to the combination of the cloud cover, precipitation, and cold front.
Colder air will spill in Wednesday morning associated with a cold front. Highs Wednesday afternoon will be 10-15 degrees cooler than today with a noticeable increase in westerly winds.
400 AM MDT Tue Jul 23 2019 The upper level ridge will bump up just a little more today, centering itself over eastern Utah and Western Colorado. Current water vapor imagery shows some drying on the northern and eastern side of this ridge, over our forecast area. That said, the higher terrain and diurnally driven upslope across the Front Range Mountains and Foothills should still be supportive of relatively high coverage.
Hot weather will continue across the region through the remainder of the week as high pressure over the Desert Southwest gradually extends north and west.
Scattered showers and thunderstorms will primarily affect KMEI, KPIB and KHBG during the afternoon as a cold front moves through the area. /GG/ Today and Tonight: While the pre-frontal trough has cleared the forecast area this morning, actual cold front was poised to enter the northwest corner prior to dawn. Drier/cooler air will be deepest over northern portions by late afternoon and it is here where decoupling will be most efficient.
620 AM CDT Tue Jul 23 2019 We will start the period with a large area of high pressure centered over the 4-corners area, with a ridge stretching north across MT, Alberta, and Saskatchewan. At the surface, the 1026mb high over eastern NE still had a ridge extending up across our entire area as well as much of ND and western MN.
An upper trough off the PacNW coast will be nudging inland today and this will produce an increasing onshore surface pressure gradient over western Oregon. The upper trough swings through overnight with any evening convection quickly dying off followed by dry and warming weather Wed-Fri.
500 AM MDT Tue Jul 23 2019 Upper ridge extending into Montana pulling hot air northward. At low levels, high pressure over the plains, and southeasterly winds, are pulling Gulf moisture northward. Combination of weak wave lifting out of the Great Basin and trof moving into the Pacific northwest will continue to produce isolated showers or thunderstorms over central/western Montana today.
620 AM CDT Tue Jul 23 2019 The current upper-air pattern is amplified in nature, featuring a ridge over the Rockies and a downstream trough over the eastern third of the nation. While the mid to upper-level high is forecast to remain anchored near the Four Corners region through the remainder of the week, a series of perturbations embedded within the polar belt of westerlies will gradually dampen the ridge across the northern tier of states. The result of that process is the deepening of a surface lee trough over the High Plains the subsequent advection of a progressively warmer air mass into the region over the course of the work week. -Canadian border this weekend into early next, promoting at least a temporary retrogression of the upper high from the Four Corners into the lower CO Valley.
350 AM MDT Tue Jul 23 2019 Upper-level ridging will quickly build into the region today w/ H5 heights climbing to 594-596 dam by 00z Wednesday. Considerably warmer today, with high temperatures in the 80s for much of the CWA. A flattening ridge is expected to give way to fairly active quasi- zonal flow on the northern periphery. Thunderstorms are possible each afternoon & evening across portions of southeast Wyoming and the western Nebraska Panhandle, w/the best chance over the higher terrain.
Upper Level high pressure across the southwest CONUS will continue through the end of the week.
With the upper trough stalling over the region today, still anticipate a few showers to refire along the ridges this afternoon in shallow instability. Upper trough will stall over the region today. I think the main affect for the area will be a slowing of the eradication of the cloud cover and continuing the risk for isolated to scattered showers over the SE ridges. Trough axis finally rotates through the area late tonight. Models are indicating an area of showers and cloud cover, associated with the main wave rotating through the trough, diving southward from Lower MI in northern OH this evening. However, we will likely see some increase in cloud cover overnight, as the wave digs southward toward the trough axis. The area will remain under the influence of the trough on Wednesday.
406 AM CDT Tue Jul 23 2019 Expect warmer temperatures today with highs in the 80s. Instability creeps back into the forecast this afternoon as southerly return flow increases, but very warm and dry conditions in the lower layers of the atmosphere should inhibit any convection. Regarding storm mode: deep layer shear vectors are forecast to be perpendicular to the trough, suggesting the potential for discrete supercells with any storms that can mature. With that said, severe weather certainly looks possible and the Storm Prediction Center has placed areas along and west of the highway 83 corridor in a marginal risk of severe weather in the latest Day Two Convective Outlook.
412 AM CDT Tue Jul 23 2019 Convection continues to increase this morning across the nearshore coastal waters well in advance of the long awaited cold front which is somewhat difficult to pin down based on this morning's surface map. Precipitation will end behind the front with modest northerly flow ushering in somewhat cooler and drier air through the afternoon and evening.
Mid-level high pressure has become centered just west of Grand Junction early this morning and circulation around the high has kept deep subtropical moisture south of the forecast area over New Mexico and Arizona. Expect temperatures to be a bit cooler, though not nearly as much as suggested by the NBM. A mid-level low pressure trough is expected to move across the northern Rockies on Wednesday, forcing the mid-level high pressure center southward.
Given the high moisture content, development of the east coast sea breeze should generate some convection itself especially over north Brevard/Cape area early this afternoon before the west coast breeze dominated storms arrive later in the day. Have allowed the Caution to expire over the offshore waters as TD#3 continues to lift N/NE away from the area and has in fact opened up into a trough per NHC.
Radar trends over the last hour have increased across portions of south central Texas early this morning as a cold front advances southward. As the front progresses southward this morning, the higher rain chances will follow, favoring areas generally south of Highway 90. Farther north, drier air in the low-levels will move in, bringing an end to convection. High temperatures today will be cooler than yesterday, with upper 80s in the Hill Country to mid 90s along the Rio Grande. Dry weather is in store tonight and Wednesday as northeasterly winds in the low-levels continue to bring drier air into the region.
353 AM MDT Tue Jul 23 2019 Modest N-NNW flow aloft will prevail over the Tri-State area -- on the eastern periphery of a pronounced upper level ridge over the Rockies. Wed-Sat: Modest NW-NNW flow aloft will prevail over the Tri-State area, on the ENE-NE periphery of an upper level ridge situated over the Rockies. Sun-Tue: GFS/ECMWF guidance indicate that the upper level ridge over the Rockies will de-amplify/flatten this weekend, placing the Tri-State area in closer proximity to the mid-latitude westerlies.
631 AM CDT Tue Jul 23 2019 High pressure building into the middle of the country this morning, with northwesterly flow aloft established over the Plains and into the Midwestern states. Have warmed a degree or so over blended MOS as this morning is also a little warmer than 24 hrs ago.
The boundary layer as a whole is a little drier and warmer than yesterday, with MLCape values along the lines of one half of what was found yesterday, and 0-3 km MLCape about one quarter of yesterday's values. The major forecast concern for the day is the development of a cumulus line, especially over the lower Keys.