Aikyam-Lab/Synoptic-Bench huggingface dataset:
A passing trough will bring gusty winds, much cooler temperatures, and slight chances for precipitation this weekend. The impending trough of low pressure is still on track to bring a sharp taste of fall to northern Arizona this weekend. As the trough digs into the Southwest on Saturday, a tightening pressure gradient will set up strong south to southwest flow over Arizona.
(Today through Saturday) With high pressure lingering at the surface and ridging moving into place in the mid-levels, expect a fairly un-eventful next day or two weather-wise. Some semblance of weak wedging is likely to stick around in the near term (and potentially longer) given favorable positioning of high pressure across New England/southeastern Canada. Thanks to a drier column associated with strengthening ridging aloft, sensible effects of this will be limited (minimal cloud cover and almost no impacts on daily highs), and will primarily be reflected in winds steadily out of the northeast.
641 AM EDT Fri Sep 29 2023 High pressure across the region will remain in control through the weekend. The synoptic situation will be changing today as the upper level trough will be swinging through the eastern US and moving offshore this evening. With the trough moving east an upper heights rising a bit along with the heating high temperatures will be a few degrees warmer generally in the low 80s. Expect highs in the low to mid 80s with lows overnight in the upper 50s to low 60s. A persistent synoptic pattern will continue through much of the forecast period: ridging over the eastern US with a upper level troughing offshore.
633 AM CDT Fri Sep 29 2023 (Today through Saturday Night) High pressure centered across the central/eastern CONUS will continue to dominate the weather across most of Southeast TX today and Saturday. The main weather maker will be a trough/weak easterly wave over the northern Gulf of Mexico. This trough is progged to move westward into the Upper TX coast and along the coastal counties today and should remain over the region through Saturday evening; resulting in elevated rain and storm chances. Most of this activity should remain along the coast with the highest chances offshore.
624 AM CDT Fri Sep 29 2023 (Today and tonight) Flow aloft has gradually begun backing early this morning ahead of an amplifying longwave trough over the western CONUS. However, the negatives still look to outweigh the positives given fairly significant capping and lingering subsidence associated with continuing upper level ridging over the Rio Grande Valley, with hi-res guidance currently appearing too aggressive regarding convective coverage late this afternoon through this evening.
Temperatures will remain cool for the start of the week, but readings will rebound back to near-normal levels by the middle of the week as high pressure builds over the region. Friday and Saturday A transition to more fall-like weather will begin today as a trough of low pressure developing off the Oregon coast moves towards the region. As far as precipitation associated with this low, it still appears that most of the deeper moisture will be intercepted by the Sierra, but some spillover is expected in the northern Owens Valley and Southern Great Basin. The highest QPF amounts remain over northern Inyo and Esmeralda counties, where.
628 AM EDT Fri Sep 29 2023 (Today and tonight) An upper trough stretching from the Great Lakes southward into the Tennessee Valley will continue moving eastward over the next 24 hours with weak upper troughing remaining along the Gulf coast. At the surface, high pressure north of the area will maintain a relatively dry northeast surface flow across the area. Elsewhere, the atmosphere is expected to remain too dry for convection, despite the weak upper troughing along the Gulf coast. Highs are expected to range from the low to mid 80s across the area with overnight lows mainly in the 60s, except near 70 along the coast.
316 AM MDT Fri Sep 29 2023 The trough over the Pacific Northwest looks to develop deeper down the west coast, possibly in the process of dropping a closed low over the Great Basin in the next few days, and not advance. Flow aloft over Colorado should remain moderate while turning more southerly ahead of that trough. There might be a little disturbance aloft coming around the trough, to little effect other than a bit of wind in the high country. A weak front today will bring temperatures down a few degrees as well but it will still be seasonally warm, about 5 to 10 F warmer than normal just about everywhere. Strong upper low will slowly track eastward across California and the Great Basin this weekend.
Highs will reach the low to mid 80s today. (Today and tonight) An upper trough stretching from the Great Lakes southward into the Tennessee Valley will continue moving eastward over the next 24 hours with weak upper troughing remaining along the Gulf coast. At the surface, high pressure north of the area will maintain a relatively dry northeast surface flow across the area. Elsewhere, the atmosphere is expected to remain too dry for convection, despite the weak upper troughing along the Gulf coast. Highs are expected to range from the low to mid 80s across the area with overnight lows mainly in the 60s, except near 70 along the coast.
925 AM CDT Fri Sep 29 2023 Rain and thunderstorms have moved out of the area and high pressure will settle in for the rest of the day. Currently, southwest flow aloft as a long wave trough remains over the western Northern Hemisphere.
1025 AM EDT Fri Sep 29 2023 Dry high pressure will gradually build into the Southeast from the north through the weekend, remaining over the region much of the workweek.
Meanwhile, departure of the thermal trough has allowed daytime highs to climb a few degrees warmer than yesterday into the upper 60s. Only caveat to this would be any lingering stratus or high cloud that could interfere with cooling prospects, but with afternoon dewpoints holding steady at 14-15 C each day and climatologically cooler/longer nights, outgoing forecast favors the more pessimistic solutions. Locations invof easterly flow off the lakes and/or cooler rural locations have the best opportunity to see dense fog formation.
1139 AM MDT Fri Sep 29 2023 Current surface analysis shows cool front east and south of the forecast area, with weak high pressure to the north. Upper level analysis shows southwesterly flow across the region, with broad trough across southwest Canada and the Pacific NW. Warmer air will build into the region over the weekend as negatively tilted ridge builds back over the Plains, ahead of digging trough across the western US.
221 PM EDT Fri Sep 29 2023 High pressure remains wedged against the eastern slopes of the Appalachians.
The trough over the Pacific Northwest looks to develop deeper down the west coast, possibly in the process of dropping a closed low over the Great Basin in the next few days, and not advance. Flow aloft over Colorado should remain moderate while turning more southerly ahead of that trough. There might be a little disturbance aloft coming around the trough, to little effect other than a bit of wind in the high country. A weak front today will bring temperatures down a few degrees as well but it will still be seasonally warm, about 5 to 10 F warmer than normal just about everywhere. Strong upper low will slowly track eastward across California and the Great Basin this weekend.
(Tonight through Saturday night) An upper level ridge extends from northern Mexico into the central Mississippi River valley with weak flow over Texas.
After that, besides a 20% chance of some light precipitation in north Douglas and Coos counties as a disturbance slides over the top of the ridge that starts to nudge in beginning late this weekend, dry and warmer weather resumes for the remainder of the upcoming work week. An approaching low pressure system is bringing showers to Coos and Douglas counties, with showers expected to develop across northern California and southern Oregon through the day. A warm front will move through the waters through this morning with breezy south winds and some rain, but seas remaining below advisory levels. Low pressure moves southward through the waters and into California today.
Otherwise, the previous forecast remains on track with southern WI being situated on the western side of influence from high pressure over the Great Lake Region.
On Saturday a trough will deepen across the western Great Basin. By Saturday evening, we will start to see chances increase as the trough and now closed low approach.
227 PM MDT Fri Sep 29 2023 An upper trough across the western U.
1229 PM CDT Fri Sep 29 2023 (Today and tonight) Flow aloft has gradually begun backing early this morning ahead of an amplifying longwave trough over the western CONUS. However, the negatives still look to outweigh the positives given fairly significant capping and lingering subsidence associated with continuing upper level ridging over the Rio Grande Valley, with hi-res guidance currently appearing too aggressive regarding convective coverage late this afternoon through this evening.
Pattern Synopsis/Forecast: Sharp mid level ridge in the process of building directly overhead early this afternoon. Especially since the lowering sun angle makes it tougher and tougher to break up the clouds (plus the flow remains on the light side). In addition, there will likely be increasing higher clouds from a weak trough approaching from the northwest.
A passing trough will bring gusty winds, much cooler temperatures, and slight chances for precipitation this weekend. Ridging over the area is retreating today with a trough digging south from our northwest. This trough is the long awaited part of the forecast that is going to bring windy conditions for the weekend.
Upper low is expected to continue to develop off the NE coastline over next 24 hours. Ridge also sets up centered over the Great Lakes/Midwest over the next 36 hours ahead of sharp digging trough over the western US, keeping the pattern a bit stagnant thanks to Omega Block look.
(This evening through Saturday Night) Dry and warmer than normal temperatures will continue through the weekend across the Ark-La-Tex. This is due to surface ridging in place across the area that will be reinforced by a quasi-omega blocking pattern across the Eastern U. The magnitude of this ridging will allow for even drier air to filter in on easterly winds with dew points slowly falling into the lower 60s.
Saturday looks fairly similar to today, with above normal temperatures (highs in the low to mid 90s) and breezy south winds.
High pressure and a drying column will result in sunny skies Saturday, and afternoon highs should have no problem rebounding into the upper 70s and mid 80s.
Also, helping to enhance llvl lift is east/southeast flow btwn sfc and 850mb, while light it helps to squeeze out additional moisture along the higher trrn of eastern VT, as light rain has just started at MPV. mid/upper lvl ridge builds into northern NY/VT from southern Canada, along with 1025mb high pres. Otherwise, light winds and warmer-than- normal temperatures will prevail. Highs will be in the lower to mid 70s, followed by overnight lows in the upper 40s to mid 50s. Ridging will remain in place through much of the work week, keeping the weather warm and dry.
Amounts will remain light to moderate, with the highest amounts approaching 1 inch in the Monadnock Region before things come to an end. Starting Saturday high pressure will begin to assert dominance over the area and the forecast will remain sunny, dry, and mild through the end of the week.
1238 PM CDT Fri Sep 29 2023 (Today through Saturday Night) High pressure centered across the central/eastern CONUS will continue to dominate the weather across most of Southeast TX today and Saturday. The main weather maker will be a trough/weak easterly wave over the northern Gulf of Mexico. This trough is progged to move westward into the Upper TX coast and along the coastal counties today and should remain over the region through Saturday evening; resulting in elevated rain and storm chances. Most of this activity should remain along the coast with the highest chances offshore.
Rain and thunderstorms have moved out of the area and high pressure will settle in for the rest of the day. Currently, southwest flow aloft as a long wave trough remains over the western Northern Hemisphere.
1232 PM CDT Fri Sep 29 2023 (Today through Saturday afternoon) Upper level high pressure remains in charge over the region today and keeps afternoon temperatures well into the 90s for most. Lows tonight settle into the mid to upper 60s for most with the higher elevations sinking into the 50s. Saturday trends cooler as the upper level ridge breaks down somewhat and shifts to the east with a large upper level trough taking hold of the Western US.
Looking at the current water vapor imagery there continues to be troughing and an upper level low forming off the west coast. Tomorrow, Saturday, look for late morning and afternoon breezy to windy southerly winds, especially for ridge tops and southerly downslope corridors mainly across our southern areas the Snake Plain.
1239 PM CDT Fri Sep 29 2023 (Today through Saturday) The upper level low pressure system that brought good coverage of showers and storms to the north half of our area yesterday will be moving out today. It will be replaced by a dry ridge that will cover much of the eastern U. As noted in yesterday's discussion, the NBM does not do well with dew points in dry ridge regimes, so I blended some raw data and MOS guidance to bring down dew points, especially in the afternoon hours when deep vertical mixing will occur. (Saturday Night through next Friday) A dry ridge will be in control of our weather for several days- at least through midweek. The ridge will bring sunny days and mainly clear nights. Temperatures through midweek will continue to be warmer than normal, especially high temps.
1138 AM CDT Fri Sep 29 2023 (Today and tonight) Today will be a near carbon copy of yesterday, with upper ridging suppressing shower and thunderstorm development. Lee trough to the west will otherwise will bring some gusty south winds mid morning through the afternoon across northern and western sections. Highs are expected to be in the lower to mid 90s.
244 PM CDT Fri Sep 29 2023 (Issued 158 PM CDT Fri Sep 29 2023) Tonight through Saturday night: High pressure situated to the east of the forecast region will bring calm, southerly winds into the overnight hours. Saturday will bring warmer than average temperatures, with central-western WI rising into the lower 80s by tomorrow afternoon. Winds will continue to remain southerly and calm as the high pressure remains off to the east, with gustier winds during the afternoon. The temperature overnight on Saturday will also be warmer than the previous day, lowering into the 60s.
A trough of low pressure visible on water vapor satellite imagery this afternoon with its axis over the West Coast will dig southwards throughout the weekend. Moisture will meet up with a cooler Canadian airmass moving southward from Alberta. The Pacific trough will form a closed low on Saturday night.
(Through Saturday) Upper ridging will strengthen through the Great Lakes with an extension of the upper high in the Midwest. South of this feature, troughing will stretch through the northern Gulf which will support the stationary boundary to the south which has resided in that area for the last several days. Surface ridging will continue building into the southern US from southern Canada with drier air pushing in. However, until that trough pushes out of the area taking the boundary with it, the Gulf and southeast Big Bend will remain with an influx in moisture.
211 PM CDT Fri Sep 29 2023 Aloft an upper level ridge axis is setting up over the area today, this will keep us dry and warm for several days thanks to a weak blocking pattern.
121 PM EDT Fri Sep 29 2023 High pressure remains wedged against the eastern slopes of the Appalachians.
On Saturday, models depict the CWA taking a more southerly aloft through the day as the western trough digs more south while moving onshore into the western CONUS. By the evening hours, an upper air low starts to develop in the base of the trough over the CA/NV border as the CWA's upper air flow turning southwesterly.
138 PM EDT Fri Sep 29 2023 Diurnal heating and building ridge of high pressure will continue to lift cloud bases through the afternoon, producing VFR conditions with broken cloud bases ranging between 3. Slow moving mid/upper trough that has led to repeated dreary days finally starts to vacate the central Great Lakes today leaving behind ample low-level moisture in its wake. Question remains on how well clouds/low level moisture mixes out by this evening when central CONUS upper ridging expands over southern lower MI following the departure of the trough. Beyond the morning fog concerns, generally quiet, warmer weather takes hold through the coming weekend and into the start of the next work week. The aforementioned central CONUS ridge undergoes downstream amplification in response to a robust upper trough digging across the western CONUS this weekend.
Drier and slightly warmer conditions look likely by Saturday, as the upper low shifts off the coast. Mean mid-upper heights/temps edge toward slightly above normal values, however the low levels (925-850 mb) will stay relatively cool with another potential push of easterly flow helping to maintain plenty of stratocu clouds and even a bit of drizzle or a brief shower across mainly the eastern half of the CWA.
(This evening through Saturday) An upper level ridge across Texas will continue through Saturday while a strong upper level trough digs into the SW CONUS. Meanwhile at the surface, high pressure to the east and low pressure across Colorado and New Mexico will continue to bring southerly winds to the region, with gustiest winds (around 20 mph) this afternoon and Saturday afternoon when the surface pressure gradient tightens. Highs today will be in the low to mid 90s, which is about 5-10 degrees warmer than normal, while some weakening of the 850 mb thermal ridge will lead to slightly cooler highs on Saturday (upper 80s to low 90s). An unsettled pattern with above normal temperatures expected through midweek ahead of our first significant fall cold front A strong, high-amplitude trough is expected to move onto the West Coast early this weekend.
1248 PM MDT Fri Sep 29 2023 Water vapor shows short wave responsible for our overnight convection now pushing through the far eastern Dakotas into the Upper Midwest, with next trof axis along the Pac NW coast and southwest flow in-between. At the surface, ridge covers the western Dakotas with early afternoon temps mainly in the 60s. Warmer air will advect back into the region over the weekend as upper trof digs across the far western CONUS and splits for a period of time.
(This evening through Saturday) As of 18z today, an elongated ridge is located over Mexico, portions of Texas, and into the Southeast CONUS. This ridge will move eastward ahead of the large, yet slightly positively tilted digging trough located over the West Coast. This afternoon, movement of the ridge eastward will allow for southwesterly flow bringing somewhat moist air in the mid-levels to eastern New Mexico. Otherwise, most areas will be dry with highs in the lower 90s and winds 15 to 20 mph. Tomorrow, as the upper trough gets closer, southwesterly flow will continue.
-Cooler temperatures prevail tonight, with lows expected to fall into the 40s across much of the area. This is in response to a deepening area of H7 low pressure expected to form in the southwestern CONUS, along with a ridge building over the Great Lakes Region. The result will be an increase in moisture heading into Saturday, along with warm air advection developing in the lower levels. The highest instability is expected to remain east and southeast of the area, thus strong to severe thunderstorms are only minimally supported. Following this boundary is slightly cooler and drier air, with dew points in the 40s across much of the area tonight.
Sunny breaks this afternoon across the Laurel Highlands has helped a couple of spotty diurnal showers develop on the backside of upper level low migrating over CPA. Low temps will be similar to last night and fairly uniform in the low-mid 50s which is +5-10F above end of September climo. Can't rule out a stray shower over the far eastern zones on the backside of departing upper low, but probs are 10% or less for now.
(This afternoon through Saturday) Upper level height rises are ongoing across the region this afternoon as a ridge builds across the ArkLaMiss to our west. As a result, the overall airmass will begin to moderate and warm as the upper ridge builds in from the west. Following some light jacket-worthy temperatures this morning in the upper 50s and lower 60s, we should be a little warmer overnight due to the airmass modification. A 591 decameter ridge at 500mb should be centered just to the north of Central Alabama during the day on Saturday, along with plentiful amounts of dry air across the atmospheric profile.
246 PM MDT Fri Sep 29 2023 Models continue to agree on the evolution of a deepening trough over the western states through much of the weekend. As the trough digs along the west coast tonight a weak warm front is progged to lift over our region.
1247 PM CDT Fri Sep 29 2023 (Today through Saturday) Lower to mid level ridging today relents on Saturday to allow for a surge of deeper moisture leading to well above seasonal normal moisture levels (PWs).
226 PM EDT Fri Sep 29 2023 Dry high pressure will gradually build into the Southeast from the north through the weekend, remaining over the region much of the workweek. A cold front will gradually approach out of the west late in the week, bringing the potential for rain back into the forecast Friday and beyond. As of 210 pm EDT Friday: The latest water vapor imagery indicates upper trough axis positioned east of the forecast area, with considerable mid/upper level drying occurring over the CWA in its wake. SPC Mesoanalysis depicts weak surface-based instability along the southern escarpment of the Blue Ridge. Heights will otherwise rise through the period, as prominent upstream upper ridge attempts to build into the East. with a 591+ dm ridge in place over the eastern Great Plains and extending well northward into the Great Lakes.
1240 PM CDT Fri Sep 29 2023 Rain and thunderstorms have moved out of the area and high pressure will settle in for the rest of the day. Currently, southwest flow aloft as a long wave trough remains over the western Northern Hemisphere.
Highs will reach the low to mid 80s today. (Today and tonight) An upper trough stretching from the Great Lakes southward into the Tennessee Valley will continue moving eastward over the next 24 hours with weak upper troughing remaining along the Gulf coast. At the surface, high pressure north of the area will maintain a relatively dry northeast surface flow across the area. Elsewhere, the atmosphere is expected to remain too dry for convection, despite the weak upper troughing along the Gulf coast. Highs are expected to range from the low to mid 80s across the area with overnight lows mainly in the 60s, except near 70 along the coast. (18Z TAFS) VFR through the period with northeast surface winds as high pressure resides to the north.
1211 PM CDT Fri Sep 29 2023 Water vapor imagery early this morning was showing a pronounced upper ridge centered over Missouri that the HREF continues to build over the Midwest the next 36 hours. This front is forecast to move slightly to the northeast through tomorrow, but subsidence underneath the upper ridge and weak low level forcing will keep our weather dry.
Temps aloft are a tad cooler than yesterday, around -6 to -7C at 500mb, and there are some limited pockets of drier air aloft, so a few stronger storms are still possible.
A low pressure trough will deepen down the west coast today then move inland over California and Nevada tonight and Saturday, spreading precipitation across southeast Oregon and southwest Idaho.