Aikyam-Lab/Synoptic-Bench huggingface dataset:
Latest water vapor imagery shows upper trough in the southwest states and another across the northern Plains at 19Z. Highs on Wednesday look to warm up to the lower 70s. Ahead of these waves the southerly flow will support moisture return in the high plains. This will drive a cold front through the area, although there are some timing differences among the deterministic guidance.
348 PM CDT Tue Sep 26 2017 (Tonight and Wednesday) Water vapor imagery this afternoon depicts a deep upper low spinning over the Desert Southwest with disturbances rotating around the eastern periphery of the low. Meanwhile, a cold front is draped across the Big Country with temperatures in the 50s and 60s behind the front.
Cold front will continue to push across Eastern Oklahoma and Northwest Arkansas through the TAF period. At mid morning the cold front extended from West Texas through Northeast Oklahoma. the cold front is expected to continue to slowly push across the CWA with rain chances spreading into parts of Southeast Oklahoma and Northwest Arkansas. Afternoon temperatures behind the front and underneath cloud cover are forecast to remain in the low/mid 70s today.
251 PM EDT Tue Sep 26 2017 Current surface analysis reveals very calm and tranquil weather in the lower Ohio Valley, while Hurricane Maria spins off the North Carolina coast to the east, and a strong cold front advancing toward our region looms off to the west. The cold front currently in the Midwest should move through our CWA early Wednesday morning at the surface as winds switch to the north and northwest, but another warm and muggy day will be in store Wednesday as the bulk of the colder/drier air lags behind. Low level lapse rates will steepen some behind the cold front and result in "popcorn" convection developing Wednesday afternoon, though warm air in the mid levels will keep instability in check and keep showers/storms relatively weak.
343 PM CDT Tue Sep 26 2017 Latest water vapor imagery shows upper trough in the southwest states and another across the northern Plains at 19Z. Highs on Wednesday look to warm up to the lower 70s. Ahead of these waves the southerly flow will support moisture return in the high plains. This will drive a cold front through the area, although there are some timing differences among the deterministic guidance.
1212 PM CDT Tue Sep 26 2017 Water Vapor imagery this morning showing longwave troughing extending from eastern MT through the 4-corners area in the southwest US. Expecting a few thunderstorms to result across central WI while the showers will be diminishing at least west of the Mississippi River behind the cold front. Look for skies to gradually clear from west to east overnight as high pressure builds in from the Plains. High pressure slides across the area Wednesday night with mostly clear skies and cool temperatures. Look for lows in the lower to middle 40s.
202 PM EDT Tue Sep 26 2017 Upper level ridging will hold for another 12 to 18 hours across southeastern Michigan before a cold front finally pushes across the area. The wind shift is expected to push across the area in the 09-12Z timeframe with the cold front itself likely lagged. There uncertainty regarding overall likelihood for MVFR and IFR post wind shift or cold front at 11Z. One more day with high temperatures topping out at 90 degrees, as the trend of the cold front looks to be a bit slower. With the surface cold front looking to come through Wednesday morning, should allow Detroit to hit 80 degrees on Wednesday before the deeper cool air can become established.
238 PM MDT Tue Sep 26 2017 High pressure will gradually build east across the Pacific Northwest and Northern Rockies tonight through the remainder of this week for warming and drying conditions.
Onshore trends had the expected results today with coastal temps running cooler but valleys and areas further inland either little change or slightly warmer. Models showing about a half mb onshore trend Wednesday with similar northeast winds aloft so coastal highs tomorrow should be about the same as today or slightly cooler depending on how much, if any, marine layer clouds form overnight. The NAM has trended drier in the lower levels the last couple runs south of Pt Conception and this seems like the way to go given the lack of advancing low clouds offshore. Further inland likely another morning of weak offshore breezes, generally under 25 mph with temps again about the same as today or slightly warmer (mainly far interior).
Meanwhile, weak upper ridging will persist from western Gulf of Mexico into the Mid Atlantic states. Also a weak upper low will be centered over the northeast GOM, and Maria will continue to lift north then east off the Mid Atlantic coast into the north Atlantic maritime waters. Highs will reach the lower 90s inland and and upper 80s along the coast.
Gusty east winds are possible near the ridge lines again tonight. A ridge of high pressure along the west coast is gradually getting stronger leading to a slow warming trend. Few changes were made to the short term part of the forecast as a ridge remains to the west with a trough well to the east. In the base of the trough is a quasi-closed low. gusty easterly ridge winds are expected again tonight. By Wednesday the ridge begins to shift east as the trough weakens and moves away. This will result in less wind at the ridges and slow warming trend.
Brownsville radar currently shows some lingering convection across the western portions of deep south Texas and a few streamer showers moving northwest across the lower Texas coastal waters. /issued 439 AM CDT Tue Sep 26 2017/ SHORT TERM (Now through Wednesday): Deep South Texas will remain between a large-scale trough/500mb low over the western half of the U. and a 500mb ridge over the western Gulf of Mexico through the period. Brownsville radar currently shows the heaviest activity across Zapata county with a few streamer showers moving northwest across the lower Texas coastal waters. The best rain chances will be across Zapata, Starr and Jim Hogg counties due to higher QPF and close proximity to the 500mb trough. Abundant cloud cover and increase rain chances should hold high temperatures down into the low to mid 90s for today and Wednesday.
335 PM CDT Tue Sep 26 2017 A cold front was situated from Freeport down to Burlington and Keokuk. Well to the west, over the NW section of the CWA, highs were only in the lower 70s. For tonight, it will be much cooler with lows in the upper 40s to mid 50s as high pressure begins to take hold.
311 PM EDT Tue Sep 26 2017 High pressure will continue to shift east tonight. A cold front will approach from the west on Wednesday and will cross the region Wednesday night.
146 PM EDT Tue Sep 26 2017 Dry and warm high pressure will remain across the region through Wednesday as Hurricane Maria moves slowly northward off the NC coast.
The cold front is arriving in south central WI this afternoon, marked by a wind shift to the west.
Northerly flow tonight into Wednesday morning should help maintain some cloud cover over the region, and even a few light showers, primarily over the higher terrain. With the low levels of the atmosphere remaining saturated, fog may become a bit more widespread for Wednesday morning.
Temperatures will warm over the weekend as strong high pressure builds to our north.
The associated trough axis extends southward over NE this evening and tonight, which will support storm development along surface boundary in that area. Mostly clear skies should allow temperatures to drop into the lower to mid 60s.
With low pressure beginning to take shape over Florida and the coastal waters might see a few showers impinge on the coast toward sunrise and will keep some showers in the vicinity for Craig Airport. ESE winds will continue to back to the E into this evening over the waters as broad low pressure just south of Tampa Bay on the SW FL Gulf Coast gradually tracks eastward across the Florida peninsula through Saturday. As the low emerges offshore of the Florida north-central Atlantic coast Saturday, NE winds will increase over the local coastal waters as a wedge of high pressure strengthens down across Georgia.
The low clouds and fog should then dissipate by noon on Saturday. Deep layer shear continues to remain on the low end range of 10 to 15kt.
The 19z MSAS surface analysis showed an area of high pressure across southern Ontario into the Great Lakes. Dew points over northeast WI were still in the middle to upper 40s, while dew points over eastern MN/western WI were in the lower 60s. A warm front was situated from eastern SD southeastward into southern IA. Min temperatures to range from the lower to middle 40s far northeast WI, to the lower 50s across central WI.
1243 AM EDT Sat Aug 26 2017 High pressure and dry conditions are expected through the weekend.
This will likely remain to the west, where the low level jet will be set up. Still, there should be enough upward vertical motion to keep the low end PoPs for showers later tonight towards the Wisconsin Dells area, and Saturday across mainly the northwest half of the forecast area.
This is causing a large increase in convection btwn Aberdeen and Pierre just west of surface warm front which was from just east of Aberdeen to Valentine Nebraska. Low pressure in south central SD will move east-northeast thru the evening and night into west central MN overnight. This boundary will move only into central ND tonight and then basically wash out Saturday as low pressure moves east thru central/eastern MN.
A high pressure ridge centered over the Great lake states will continue to build southward into GA through Sat.
This activity is due to an upper level trough that extends from West Texas to the Central Plains. The trough will weaken and move east over the next 24 hours and high pressure over the western U. High pressure and dry conditions do not usually mean cool air for our CWA, but that is what MEX guidance is indicating. The reason the MEX is so cool is the GFS is advecting cooler air from Hurricane Harvey west due to easterly and northeasterly surface winds around it's circulation. While there is no doubt this will occur, it is hard to imagine we will stay in the 80s without a cold front or appreciable rain so this forecast is generally several degrees higher than MAV/MET/MEX guidance and closer to the ECE guidance.
956 PM EDT Fri Aug 25 2017 High pressure continues over the northeast states and Great Lakes and extending south to the Ohio and Tennessee Valleys tonight. Temperatures are mostly in the lower 60s to the lower 70s except in the upper 70s at Chattanooga.
A trough of low pressure extended from eastern Quebec into New England. A low amplitude ridge extended across the eastern Dakotas into Manitoba where the ridge amplified north into Hudson Bay. Upstream of this ridge, a closed low was noted over northern Alberta. At the surface, weak low pressure was noted over the northeastern Nebraska panhandle. A frontal boundary extended northeast of the low into northeastern South Dakota and west northwest of the low into northeastern Wyoming. With the boundary currently lying from Pine Ridge SD to just north of Winner SD, am expecting convection to fire INVOF this boundary first. As was the case with the inherited forecast, will maintain the highest pops across north central and northeastern portions of the forecast area.
A gusty east canyon/gap wind will likely impact KABQ this evening, but speeds will likely remain on the lower side.
730 PM EDT Fri Aug 25 2017 Upper air pattern consists of a 500 mb ridge over the northern plains up through Manitoba this morning.
625 PM CDT Fri Aug 25 2017 A weak trough is moving across the Plains as Hurricane Harvey is intensifying with the warm waters just off of the south Texas coast with anticipated landfall to be this evening on this category three storm meaning possible wind speeds of 110-130mph.
Upper level ridging combined with PW values between 1. The upper ridge weakens slightly on Saturday with some moisture recovery, especially along the coast. Highs on Saturday will climb into the low 90s in most areas with some mid 90s possible over eastern zones.
Quiet forecast through most of the weekend as high pressure drifts slowly eastward across the Great Lakes. With a fairly dry airmass and a northeast component to the wind field around the high, expect another cool night tonight with lows dropping into the 40 degree range.
A warm front currently located somewhere along the I-90 corridor, will continue to lift north-northeast this afternoon and evening, increasing the instability across the area. Scattered strong to severe storms are possible late this afternoon and evening as the aforementioned warm front interacts with an upper-level trough.
1210 AM EDT Sat Aug 26 2017 High pressure under northwest flow aloft will maintain cool temperature for the weekend.
There will be an influx of cirrus on Saturday associated with tropical cyclone Harvey, so filtered sunshine expected throughout the day.
Quiet weather continues across the area thanks to high pressure settling in. With high pressure influences over the area, only sct cirrus will affect the terminals.
Surface observations and radar imagery has been the best way to see this low as southwest onshore flow is apparent over southwest Florida while a more northeast flow persists north of Tampa Bay and along the Nature Coast.
We may also see a few "showers" develop along and west of the I-49 corridor, however this activity will likely be in the form of virga due to dry air in the low levels of the atmosphere.
1127 PM CDT Fri Aug 25 2017 Visible shots reveal the higher clouds readily seen by observation and confirmed with some moisture showing up at and above 500 mb on gridded time/height cross sections. Surface obs/analysis shows temps pushing the lower 80s as dew points hover in the upper 50s/nr 60F in light nely flow.
Numerous wind gusts reports have been received of wind gusts over 100 mph with the highest report of 131 mph near Port Aransas.
Given a large ridge of high pressure over the western United States, and a northwest flow aloft east of the Rockies, there is nothing to lift the remnants of Harvey to the northeast. Instead, Arkansas will enjoy high pressure through the first part of the weekend. Surrounding the high, the airmass will be comfortably dry, and below average temperatures will continue.
Synoptically quiescent conditions with high pressure providing dry weather tonight and right through the weekend. Despite the cooler start, highs will be a little warmer, thanks to slightly warmer temperatures aloft and more sunshine. Saturday night will be a near repeat of tonight, though we'll be a few degrees warmer overall because we'll top out warmer during the day. The short term will likely start off with the upper level trough lingering overhead with a minor impulse rotating through.
A weak flow with a broad area of high pressure across the region. Isolated showers and storms have started to develop across the area this afternoon, although the vast majority have been confined to the higher elevations through 21Z.
908 PM EDT Fri Aug 25 2017 Canadian high pressure will take charge through the weekend providing dry quiet weather with below normal temperatures. Temps are falling quick across the region as skies have cleared out and high pressure is building at the region. Lowered temps a couple of degrees for tonight, temps are expected to fall into the low/mid 40s. A short wave is moving east of the area with the base of one upper level trough. High pressure at the surface over the western Great Lakes will move in tonight with dry air and nearly calm winds. Highs in the low 70s. The base of the upper level trough will move east the rest of the weekend. Slow warming but still cool with high pressure over the northeast US.
707 PM EDT Fri Aug 25 2017 High pressure will keep fair weather through the weekend.
Surface analysis this afternoon places Hurricane Harvey just southeast of Corpus Christi Texas while a ridge of high pressure is centered over the Great Lakes Region. This is resulting in rain free weather across the Mid-South with temperatures as of 2 PM CDT in the lower to middle 80s at most locations.
910 PM EDT Fri Aug 25 2017 High pressure under northwest flow aloft will maintain cool temperature for the weekend.
High pressure building over the region will result in a warming trend through the weekend. An upper level ridge centered over the Great Basin and Desert Southwest began to expand to the west and over California today, resulting in warmer temperatures across our inland areas. The upper ridge is projected to strengthen across California through the weekend, with 850 mb temperatures forecast to climb to 26 deg.
1136 PM CDT Fri Aug 25 2017 A weak trough is moving across the Plains as Hurricane Harvey is intensifying with the warm waters just off of the south Texas coast with anticipated landfall to be this evening on this category three storm meaning possible wind speeds of 110-130mph.
A very warm upper level ridge is beginning to build north from the Great Basin, resulting in enough subsidence to suppress convection, despite moderate instability and above average precipitable water.
Expect a trough of low pressure to our north to swing southeastward overnight. While there could be some development along this trough. where forcing from the low level jet should aid in additional convective development overnight. expect the aforementioned trough to dissipate across the local area and for a partly sunny and dry afternoon for just about everyone. High pressure is expected to strengthen across the Great Basin to begin the extended periods. as we will be situated between high pressure to our west and low pressure across the Great Lakes region. Before the area of high pressure to our west builds further north and settles into the Great Basin late in the weekend.
High pressure building in over the region will result in significantly warmer temperatures over the weekend. Synoptically an expanding ridge of high pressure will continue to advance toward our region from the southeast which will lead to additional compressing of the marine layer along with a quicker burn-off tomorrow.
1027 mb high pressure over nw lower MI and northern Lake MI was ridging into central IL and providing partly to mostly sunny skies this afternoon over CWA with ENE winds 5-10 mph. Lows in the mid 50s again tonight with a few cooler spots in the lower 50s as we have seen past 2 nights.
Southerly flow is increasing across Iowa this afternoon with high pressure to the east and low pressure lifting into western Nebraska. The low level jet will remain established overnight and will continue to lift theta-e advection north and bring instability into northwest Iowa late. High temperatures will be in the low to mid 80s south with more sunshine to the mid 70s north. While the upper level ridge amplifies to the west, an upper level low will settle south through the northerly flow into the Upper Mississippi Valley and western Great Lakes region.
The low level jet will keep this activity in this vicinity and possibly shift it northward overnight. Otherwise the radar has been showing some smaller echoes expanding in coverage, mainly along and north of the highway 2 corridor. This is causing a large increase in convection btwn Aberdeen and Pierre just west of surface warm front which was from just east of Aberdeen to Valentine Nebraska. Low pressure in south central SD will move east-northeast thru the evening and night into west central MN overnight. This boundary will move only into central ND tonight and then basically wash out Saturday as low pressure moves east thru central/eastern MN.
Western GRT LKS high pressure maintaining mainly dry conditions acrs the area, and will look to continue to do so through Saturday.
A dry northwest flow will couple with the aforementioned area of high pressure to keep conditions dry over the next few days.
Otherwise, Sat shud be similar to today, but slightly warmer. Tilly A building ridge axis across the west coast will create northwest flow aloft across MO/IL this weekend.
1015 PM EDT Fri Aug 25 2017 The forecast area will be between a frontal boundary off the Southeast Coast and high pressure ridging southward along the Appalachians over the weekend. An area of low pressure will develop along the front and lift northeastward.
Proximity to weak tropical low pressure and continued deep moisture across the region will keep an above normal threat for NMRS showers and ISOLD-SCT storms in the forecast during the late morning and afternoon on Saturday. Weak tropical low pressure across west-central FL is forecast to slowly drift into the central peninsula overnight. The weak tropical low pressure will still be over/near the area with mainly southwest flow initially, potentially becoming northeast/variable near shore/Volusia coast with possible cautionary statements necessary over the open Atlantic for wind speeds of 15-20 kts.
High pressure from the Great Plains to the east coast will control Indiana weather through Saturday. Late in the weekend, we should come under the influence of low pressure developing in the Mississippi Valley. The low pressure won't move much until midweek.
759 PM EDT Fri Aug 25 2017 The forecast area will be between a frontal boundary off the Southeast Coast and high pressure ridging southward along the Appalachians over the weekend. An area of low pressure will develop along the front and lift northeastward.
Precipitation chances through the forecast period have been adjusted to reflect the current coverage of rainfall, as well as the scenario that Harvey will move inland along the Lower Texas Coast and persist there, with the greatest rain chances subsequently over the northern half of Deep South Texas in closest proximity to Harvey.
Lower level moist confluent flow, associated with the previously mentioned trough, will remain near the Keys. In addition, the background ridge will not be conducive for shower development. Surface winds will generally be light out of the southwest due to a narrow ridge across Keys waters. On this date in Florida Keys weather history, in 1956, the high temperature at Key West International Airport was 95 degrees.
Quiet weather continues across the area thanks to high pressure settling in. High pressure will allow for great flying weather.
537 PM MDT Fri Aug 25 2017 Cold front across eastern Montana this afternoon will drop southward across eastern Wyoming and western Nebraska tonight. It appears that we will dry out significantly Saturday on the northeast side of the low to midlevel ridge axis. Looking like a warm and pretty dry week for the CWA as the area resides under the northeast part of a large upper high that will be anchored over the southwest part of the CONUS.
Upper level ridge centered over the Desert Southwest and Great Basin will keep warm and mainly dry conditions over the area. Isolated showers and thunderstorms will be possible through early evening, mainly over the higher terrain and across the eastern plains. The upper level ridge intensifies a little on Saturday. Expect slightly warmer temperatures over northeast Colorado with highs in the lower to mid 90s. There is a slight chance for weak convection over the higher terrain and along a boundary over far eastern Colorado.
Models suggest this low to move slowly across Central Florida tonight into Saturday. This sw flow will continue providing deep moist advection as the low pressure shifts northeast across Central FL into the Atlantic by Saturday.
726 PM EDT Fri Aug 25 2017 High pressure and dry conditions are expected through the weekend.
This should allow some of the cloudiness ahead of this wave to shift into the lower Great Lakes on Saturday. The southerly lower level flow ahead of this system will steer some slightly warmer air into the region, which should allow temps to inch up a bit more than the seasonably cool conditions today, in spite of some increased clouds. KMD 241 PM CDT Strong upper ridge will be centered over the Intermountain West throughout most of the extended timeframe with downstream troughing in place across the Great Lakes region resulting in continued below normal temperatures through at least the first half of the upcoming week.