Aikyam-Lab/Synoptic-Bench huggingface dataset:
A low pressure system will move along the Canada/northwest Montana border today, pushing a weak cold front through the region this morning. Chilly temperatures are expected for Tuesday morning as clear skies, and a cooler and drier airmass reside over the region.
606 AM CDT Mon Aug 23 2021 (Today and tonight) An upper level ridge will continue to dominate the weather across West Central Texas through the next 24 hours, with no rain forecast. Overnight lows will be in the low to mid 70s.
SMOKE TO PERSIST THIS WEEK WITH WARMER TEMPS LATER IN THE WEEK. A broad positive tilted upper trough will loiter till mid-week mostly from southwest Canada, southwest into WA/OR, and then off-shore the CA coastline. Model guidance suggests that an upper ridge building northwest into the Great Basin region this same forecast period will maintain a near-constant west to southwest upper flow over the Sierra and western NV through Tuesday. From mid-week on, the upper ridge looks to weaken and recede east. This will allow the upper trough to take advantage of the open opportunity and advance into Pacific Northwest dragging its southern extension across CA/NV.
* Low confidence in cigs aob 5000 feet Tuesday morning An elongation of the subtropical ridge across the central and eastern US will occur over the next couple of days, with the ridge expected to persist into the weekend. In fact, recent medium range model trends build the ridge over the ern US over the weekend, indicating a likely hot and humid last weekend of August. This will result in a drop in surface dewpoints (possibly down into the low 60s) this afternoon, causing in a lowering of the humidity.
Today through Tuesday night: A closed low over southern British Columbia will send a mid level wave southeast clipping far northern Washington into the Idaho Panhandle this afternoon into the early evening. Tuesday and Tuesday night the dry air lingers over the region as the flow aloft gradually shifts from north to southwest in advance of an upper level trough.
(Today through Tuesday afternoon) A broad ridge that has been expanding over the past few days now encompasses most of the southern CONUS and continues to strengthen, serving as the dominant feature in our weather pattern this week.
630 AM CDT Mon Aug 23 2021 An upper level ridge is in place over the region and will remain the focus for the areas weather through this week. For today, a few upper level short waves will move through the upper ridge and bring the potential for some showers or an isolated thunderstorm to areas mainly east of Highway 65 as early as late this morning and into this afternoon. This will work to bring warmer and moist air into the region with afternoon temperatures today into the lower to middle 90s.
Arthur Satellite imagery shows an upper low over southern BC and southwest flow aloft in our region. There may be a smaller risk of weak thunderstorms in our northwest by late afternoon, but better chance (in a relative sense) is after 00z as a Canadian cold front drops thru the area. Cold front itself will produce a shift to gusty NW-N winds this evening, with breezy conditions lingering thru the night and into Tuesday in our east. Regarding fire weather: Warmer and dry conditions (RHs in teens) are of some concern, but recent significant rainfall should help to keep fire growth potential in check.
This heat will prevail courtesy of a broad upper level height ridge, extending from northern Mexico, across the southern plains, into the Ohio River Valley.
625 AM CDT Mon Aug 23 2021 H5 analysis from earlier this evening had a closed low over southern British Columbia. A weak trough extended south of this feature into central South Dakota and central Nebraska. Showers and thunderstorms had fired along this trough tonight and were continuing over east central South Dakota. Elsewhere, high pressure was anchored over the Arklatex and low pressure was located over the Mid-Atlantic states. High pressure was located over Bermuda. East of the boundary, winds were southerly and dew points were noticeably higher with readings in the lower 70s. Will keep pops low, given the low degree of forecaster confidence ATTM. Isolated thunderstorms may develop INVOF the inverted trough.
Today, clear skies help high temperatures reach into the low to mid 90s as dew points linger in the low to mid 70s. a herculean 594 dm ridge centered over Sooner State will have a series grip on on our weather this week. The ridge will stretch from NM to MO and over the Ohio Valley resulting in mostly dry, hot and sticky wx for our CWA. there appears to be a s/wave along nrn edge of the ridge to warrant a 15-20% chance in S IN. ***Temps*** It appears hump day will be the most torrid of the week as the ridge drifts ewd over Show Me State. The Bermuda Ridge retrogrades and anchors itself over NC Outer Banks with a 594-595 dm center. This ridge absorbs the earlier OK ridge and creates much more sultry air.
520 AM MDT Mon Aug 23 2021 Current surface analysis shows weakening cool front just east of the forecast area, with a Canadian cold front hanging north of the area. Another Pacific cold front lies across far western MT and ID. Temps are in the 50s and lower 60s, with 40s over the higher Black Hills. A dry airmass will settle over much of the area ahead of the cold front to the west, with low RH and breezy conditions developing in many areas. Mainly dry cold front will then move through the region from the northwest overnight and Tuesday morning, with breezy northwesterly winds behind it late tonight and Tuesday, especially across the SD plains. A troughing pattern looks to remain persistent over the Pacific NW into the Rockies, with west-southwest flow aloft into the Northern Plains.
Muggy with Lingering Storm Chances Today: The synoptic pattern today will feature an upper level ridge centered over Texas and laminar flow from southwest to northeast over the Northern Plains (between 700 mb and 200 mb). Surface dewpoints in the lower 70s and 700-500 mb lapse rates around 7. Then we can expect another warm and muggy day Tuesday with our region in the warm sector ahead of any advancing cold front.
Model soundings indicate these clouds should break up some through early afternoon, which should provide sufficient heating for highs to reach the low 90s, with some mid 90s possible where more sunshine occurs. Deeper moisture and cooler temps aloft (around -7C, potentially -9C south of Orlando, at 500 mb) should lead to higher coverage of showers and storms, especially into the late afternoon and early evening as sea breeze boundaries push inland and collide southeast of the I-4 corridor.
For the short term period, models continue to hold an upper ridge over the southern half of the country, giving a west-southwest upper flow over the area. At the surface, the aforementioned low transitions to a trough along the eastern slopes of the Rockies, with a warm front extending into central Nebraska. This morning though, some low cloud/patchy fog could develop around the low in northern/western locales, but give way to another hot day over the region. By Tuesday, high pressure builds south, with another low developing over the forecast area. No major moisture feeding into the region with the dome of high pressure aloft, so yet another hot day is expected.
For today, there is not much change in the overall synoptic pattern as the long-wave trough axis remains just off the west coast.
An upper level ridge that extends from far west Texas east into the southern Mississippi River Valley area will remain in place through at least tomorrow, and possibly strengthen just slightly. An upper level high centered over Oklahoma and Texas will dominate the weather pattern through mid-week.
237 PM CDT Mon Aug 23 2021 /Updated at 0110 PM CDT Mon Aug 23 2021/ The upper level ridge aloft has taken over across much of the southeast, with ample amounts of dry and warm air aloft. Otherwise, we're really heating up in response to that upper ridge building in, with lower 90s observed across the board early this afternoon. We shouldn't get below the low to mid 70s by daybreak however, so very muggy conditions will certainly continue.
302 PM EDT Mon Aug 23 2021 With very light steering flow overhead, the subtropical ridge axis remains the dominant synoptic feature. This TUTT feature will be working against the drier air by providing additional forcing for ascent, and helping to pool additional moisture in the vicinity of the low. Once the TUTT feature moves out into the Gulf and dissipates, the subtropical ridge returns.
Hot high pressure will suppress all but mountaintop diurnal convection Tuesday afternoon. Discussion: High pressure will continue to suppress diurnal convection even though surface humidity isn't exactly low. Tuesday high temperatures and heat indices will be hot, with temps in the lower 90s in the Valley, and heat indices a few degrees warmer than that.
309 PM EDT Mon Aug 23 2021 Sfc and upper ridging will keep us hot and dry, or more accurately just precipitation-free as it's still a humid air mass. While there will be some oppressive dewpoints in the lower/mid 70s during the mid/late morning, expect them to mix back down to around 70 in the heat of the afternoon. The GFS and Euro differ on how far the upper low will hold together as it tracks into the SE US, but regardless we should see increased moisture advect into the TN/OH valleys.
Ridging will continue to be in control across the region. Isolated to scattered showers and thunderstorms will exist Tuesday as PW values will remain on the high side.
/Updated at 0110 PM CDT Mon Aug 23 2021/ The upper level ridge aloft has taken over across much of the southeast, with ample amounts of dry and warm air aloft. Otherwise, we're really heating up in response to that upper ridge building in, with lower 90s observed across the board early this afternoon. We shouldn't get below the low to mid 70s by daybreak however, so very muggy conditions will certainly continue.
So if you thought the temperatures will getting cooler late in the day, you are mainly noticing the lower humidity. The upper ridge is shifting slightly westward across the northern half of TX, but little change will be noticeable in the first 36 hours of the forecast.
Temperatures in the Keys are ranging from the mid 80s to the lower 90s.
317 PM CDT Mon Aug 23 2021 Tranquil conditions this afternoon across the region, with high pressure in control of the weather. The upper-level ridge of high pressure will amplify over the Deep South, with hot and humid conditions prevailing both days. Abundant sunshine and southerly flow will help to push high temperatures into the low to mid 90s.
1232 PM CDT Mon Aug 23 2021 H5 analysis from earlier this evening had a closed low over southern British Columbia. A weak trough extended south of this feature into central South Dakota and central Nebraska. Showers and thunderstorms had fired along this trough tonight and were continuing over east central South Dakota. Elsewhere, high pressure was anchored over the Arklatex and low pressure was located over the Mid-Atlantic states. High pressure was located over Bermuda. East of the boundary, winds were southerly and dew points were noticeably higher with readings in the lower 70s. Will keep pops low, given the low degree of forecaster confidence ATTM. Isolated thunderstorms may develop INVOF the inverted trough.
A ridge of high pressure will build east into the region and help to bring clearing skies, very warm and rather humid conditions by Tuesday.
Subsidence from the 500mb high pressure ridge anchored over Texas will continue to suppress rain chances through Tuesday. Deeper tropical moisture lurks over the Bay of Campeche however models maintain the ridge's position limiting any significant northward seepage. Latest model PoP guidance consensus continues to range well below seasonal averages with only 10-17 percent for the Lower and Mid Valley locations Tuesday.
207 PM CDT Mon Aug 23 2021 The center of the upper level high pressure system centered over eastern Texas will expand westward over the next 24 hours. As the high continues to build westward, temperatures will be slightly warmer on Tuesday; to most people, it will feel hot.
1104 AM EDT Mon Aug 23 2021 Bands of rain showers over, and to the east of the Susquehanna Valley will gradually diminish this morning as the remnants of Hurricane Henri in the form of a vertically stacked surface and upper low move east from the Upper Delaware River Valley. A ridge of high pressure will build east into the region and help to bring clearing skies, very warm and rather humid conditions by Tuesday.
132 PM EDT Mon Aug 23 2021 Departing upper low brings a few mountain showers and storms this afternoon. A weak ripple in mid to upper level northwest flow between low pressure associated with Henri drifting from southern New York to southern New England, and ridging building in from the southwest, may help to give rise to a few afternoon thunderstorms in and near the mountains.
A few more of the CAMs runs have the first scenario, but still a few are showing some impressive updraft helicity values developing across our eastern counties as a cold front pushes into the region. The cold front will push the rest of the way through the CWA Tuesday night and any convection that does redevelop will be shunted off to the east by midnight. While there are the usual subtle variations within the cluster analyses, overall good agreement exists on a trough digging in over the Pacific Northwest and continuing to induce southwesterly flow and surface systems over the northern and Central High Plains.
A cold front will push south across the area this evening into the overnight and bring seasonably cool temperatures in the 30s to lower- 40s across the region.
This is due to a weak trough moving from west to east across the northern tier of states and southern Canada. The wind will be slightly less tomorrow, but temperatures will be nearly the same with the slightly cooler air offset by lack of clouds.
A mix of sun and clouds and cooler than normal temperatures will continue today, however cloud cover should diminish as the evening continues. Because valleys hugging the Continental Divide have already seen low temperatures near or below freezing, this temperature forecast may not come as much of a surprise. But for locations further west, including the Missoula/Bitterroot valleys, the Mission/Flathead valleys, and valleys near the Montana/Idaho valley, tonight will be the first time this season these locations could see temperatures lower to near freezing.
Otherwise tomorrow will be another hot and humid day with heat index values in the low to mid 90s. An upper wave tracking from Saskatchewan to Ontario and the associated upper trough will slide across WI early Wed morning. Another round of convection is expected to ramp up along the 850mb baroclinic zone and nose of the low level jet over Iowa and southern MN Wed night and this could roll through a portion of our forecast area late Wed night into Thu morning. There is an even better chance for Upper Midwest convection along the nose of the low level jet over central MN that rolls into WI during the late evening and overnight hours Thu night.
301 PM EDT Mon Aug 23 2021 High pressure at the surface and aloft will provide quiet weather. High pressure and plenty of sunshine on Tuesday equals to hot afternoon temperatures reaching the mid 90s across the lowlands, ranging into the mid 70s over the highest elevations. With high dew points, heat indices could reach the lower to mid 90s across much of the lowlands, even the upper 90s in spots. Summer will continue to have firm control over the region for the short term period courtesy of an upper ridge situated across the central portion of the country.
203 PM CDT Mon Aug 23 2021 Upper high located over the Arklatex this afternoon with positive ridging extending eastward toward TN. The west to east ridge will get a little more pronounced on Tuesday.
Hot and humid conditions were occuring across the area this afternoon as the upper level ridge to the south slowly nudges towards the area. Afternoon highs or on track to reach the low to middle 90s. We will likely begin to see some mixing in the afternoon which will drop dewpoints some, however warmer temps will compensate with heat index values of 100-105 still expected.
/Issued 1012 AM CDT Mon Aug 23 2021/ Building upper ridge over the plains will continue to be the main story for the afternoon, with heat continuing through much of the work week as mid level heights continue to rise. Rain/storm chances increase by the weekend, along with relatively cooler temps. Mid level heights continue to slowly rise from the south, as mid level ridge center over TX shifts up over the Red River Valley. Evidence of this drying could already be showing up in area obs, like KMLC whose dewpoint has dropped into the upper 60s from the low 70s.
102 PM EDT Mon Aug 23 2021 Isolated showers and thunderstorms will gradually diminish by early evening, with building high pressure will provide dry weather on Tuesday, with warm conditions persisting through much of the week.
55 High pressure will continue over the area today. Today Through Tuesday Night An upper ridge over the southern U. The upper low pressure over the northeast will move off the coast Tuesday. Lows at night will be in the lower to mid 70s.
Temps will be a little cooler than models indicate due to the smoke, and we have been taking this into account in our forecasts.
For the short term period, the CWA will be situated on the eastern periphery of an upper-level ridge centered over TX and OK. Highs today will be a few degrees warmer than yesterday, generally in the upper 80s to lower 90s. Models indicate something of an inverted trough/vort max just off of the GA/SC coast tomorrow afternoon and evening, so have likely PoPs across our southeastern- most counties. Highs will be a couple degrees warmer tomorrow than today, in the lower to mid-90s. 50" PWATs) that accompanied the ridge is replaced with more seasonable moisture beginning on Tuesday as an open tropical wave traversing the westernmost fringes of the Bermuda high edges toward the southeast US.
Shear is weak, especially in the lower levels through the period and the LCLs remain around 1000m.
A warm and dry airmass under an upper level ridge advects over the region today and high temperatures will be in the 80s for most. With our dry air mass relative humidities will plummet into the low 30s, and it doesn't seem out of the question to have some local minima drop just below 30%.
Thought about including a VCTS at KARA where prob is the highest this afternoon, but decided to leave out for now.
Given this, and the higher relative humidity values across far southeastern MS and coastal counties of AL/FL, a heat advisory remains in effect until 7 PM. On the flip side, with the drier and slightly warmer mid- levels we should see lower SBCAPE/MLCAPE values upwards of 2,000/1,500j/kg respectively. Highs Tuesday will be in the lower to middle 90's, with heat index values ranging between 102 and 107 degrees.
314 PM EDT Mon Aug 23 2021 High pressure at the surface and aloft will provide quiet weather. High pressure and plenty of sunshine on Tuesday equals to hot afternoon temperatures reaching the mid 90s across the lowlands, ranging into the mid 70s over the highest elevations. With high dew points, heat indices could reach the lower to mid 90s across much of the lowlands, even the upper 90s in spots. Summer will continue to have firm control over the region for the short term period courtesy of an upper ridge situated across the central portion of the country.
Tomorrow we'll continue our transition from troughing to ridging.
At the surface lee side cyclogenesis is occurring over the Northern High Plains in response to the approaching upper trough. Seems like a lot of the CAMS develop convection over the higher elevations of the northern High Plains and track it east northeast into southwest/south central ND, then intensify the convection as the low level jet/strong warm advection really kicks in later tonight. My only question is that if Convection does not occur over the high plains, or dissipates before it reaches us, will there be strong convection.
High pressure in control over the region will keep the weather benign. Of course we'll be just a bit cooler along the coast.
High pressure is set to reign supreme across the area through the work week with the center of the upper high becoming established over the southeast United States as we move into the weekend.
Tranquil weather ongoing across the Tennessee Valley this morning as high pressure amplifies and settles into the area from the west. These clear conditions will prevail through the day, helping to boost high temperatures into the lower 90s by this afternoon. Mean short amplitude troughing along the Mid Atlantic region (partially associated with TD Henri now over southern New York) will flatten during the course of tonight and on Tuesday, as upper ridging reamplifies across the southern Lower-48 into the middle of the week. Thus a repeat performance weather-wise is forecast on Tuesday, but a bit warmer. High temperatures should warm into the low/mid 90s. Dewpoint values again in the low/mid 70s will yield even higher heat index values, ranging from the upper 90s to 105 in a few places.
Center of the upper ridge and heat dome will build northward into Kansas through mid-week. It appears a bit more southwesterly flow from the high Plains and mixing in the afternoon will allow for lower dew points across western portions of central and south central Kansas. The heat looks unabated through mid-week under the upper ridge over the area. Darmofal There is some hope for tempered cooling or "less hot" temperatures sometime over the weekend, as a series of more progressive upper trofs move from the northwest across the north central conus.
/Issued 1249 PM CDT Mon Aug 23 2021/ /Through Tuesday/ It's shaping up to be another hot and humid day across North and Central Texas as a mid-level ridge continues to dominate our sensible weather. Additionally, high humidity will result in an uncomfortable heat this afternoon, especially east of I-35 where dew points will remain in the low to mid 70s. Similar weather will continue tomorrow, though slightly warmer temperatures will result in higher heat index values.
(This afternoon through Tuesday night) High pressure has been building over the region the past few days, causing our temperatures to slowly increase with decreasing POP chances. With clear skies tonight, expect cooler temperatures with lows in the mid to upper 60s. With the ridge firmly in place, precipitation chances are all but nil. A trough moving inland off the Pacific NW late Tuesday will be the next system to watch as we remain dry and warm.
1243 PM CDT Mon Aug 23 2021 (Today and tonight) An upper level ridge will continue to dominate the weather across West Central Texas through the next 24 hours, with no rain forecast. Overnight lows will be in the low to mid 70s.
1119 AM MDT Mon Aug 23 2021 Current surface analysis shows weakening cool front just east of the forecast area, with a Canadian cold front hanging north of the area. Another Pacific cold front lies across far western MT and ID. Temps are in the 50s and lower 60s, with 40s over the higher Black Hills. A dry airmass will settle over much of the area ahead of the cold front to the west, with low RH and breezy conditions developing in many areas. Mainly dry cold front will then move through the region from the northwest overnight and Tuesday morning, with breezy northwesterly winds behind it late tonight and Tuesday, especially across the SD plains. A troughing pattern looks to remain persistent over the Pacific NW into the Rockies, with west-southwest flow aloft into the Northern Plains.
An upper level ridge that extends from far west Texas east into the southern Mississippi River Valley area will remain in place through at least tomorrow, and possibly strengthen just slightly.