Aikyam-Lab/Synoptic-Bench huggingface dataset:
East and southeast winds on the back side of this high continues to bring very dry air into the Upper Mississippi River Valley. 12z models continue to show that an elevated warm front will move east across southeast Minnesota and northeast Iowa late tonight and Thursday morning and across western Wisconsin on Thursday afternoon. The HRRR continues to show that maybe some elevated showers may develop across western Wisconsin overnight ahead of this warm front. However with the low levels (sub-cloud layer) remaining very dry, this precipitation may not make it to the ground. The highest chances will be during the afternoon.
/issued 925 PM CDT Wed Mar 22 2017/ Some fog is still expected in northwest Oklahoma where dewpoint temperatures in the 50s are expected to arrive later tonight in the cooler air.
The cold front that passed through our area early today has turned stationary and is located just near the coastline; areas of patchy fog are more promising in this region and should stay south of our CWA. /12/ Prior discussion below: Tonight through Thursday afternoon, High pressure centered well to our north, will continue to build into the forecast area behind the cold front that now resides just south of the CWA. Therefore, look for cooler conditions across the CWA tonight, as lows range from the upper 40s to middle 50s.
730 PM EDT Wed Mar 22 2017 High pressure over the region tonight and Thursday will result in drier conditions, lighter winds, and clearing skies.
1036 PM EDT Wed Mar 22 2017 High pressure builds in tonight and Thursday.
High pressure will build across Arkansas overnight and Thursday. Lows tonight look good in the lower 40s to lower 50s. (ISSUED 621 PM CDT Wed Mar 22 2017 ) High pressure will build over Arkansas tonight and Thursday.
Current modest radar returns in fairly narrow swath ahead of weak wave cresting upper ridge will continue to propagate from the valley region eastward early this evening. As upper ridge shifts east region gets under mid level sw flow for tomorrow. Models still keep a deep upper low propagating across the southern/central CONUS late in the work week but continue to keep any precipitation chances associated with it to our south. As the previously mentioned upper low eventually heads towards the upper Ohio Valley region, brief upper ridging will build into the Northern Plains.
313 PM PDT WED AUG 17 2016 High pressure over the west will keep warm and dry conditions in place through the remainder of the week and into the weekend.
455 PM CDT WED AUG 17 2016 High pressure will drift east tonight with south to southeast flow gradually increasing. From mid morning into the afternoon warm and dry air will build in to the lower and mid levels allowing a cap to develop, so thunderstorm potential will be greatly diminished.
200 PM EDT WED AUG 17 2016 Cold front will move through the forecast this evening providing more rain and thunderstorms. Another cold front this weekend. saw some multicellular storms develop this afternoon with decent supercell structures, as upper level trough moves across moist and unstable atmosphere over the ohio valley. Trough will continue slide across and provide a trigger for additional convective development this afternoon. By Thursday morning the cold front should be mostly through the region.
Synoptic pattern remains nearly the same today with southerly to southwesterly flow around the western side of mid-level ridging. Somewhat curiously the high-res guidance indicates activity remaining just south of that region, however. Microburst parameters are in the low-end moderate category. Synoptic setup has not changed much in the past day or so, with a weak upper level ridge nosing into the southeast states from the western Atlantic. Along the periphery of this ridge, from east Texas up to the Ohio Valley, there is a band of cloudiness and enhanced moisture. Over the weekend, the upper ridge is forecast to weaken further and allow a dip in the jet stream to push into the Tennessee Valley.
300 PM EDT WED AUG 17 2016 Today will be drier and cooler behind a cold front with mainly dry conditions.
Dewpoints will fall into the low to mid 60s as surface winds turn WNW with the exception of the Thumb where flow off the water will keep temps and dewpoints elevated due to marine modification.
Low pressure will move into northern Manitoba dragging a trough which extends back into Nrn California. This will impinge upon the high pressure that has been present across the southern states. The western periphery of the high, is far from clean-cut with evident disturbances across Colorado, likely aided by convection, in the presence of very weak shear. Given available data, the low end mentionable POPs continue to look warranted out east this afternoon though points south and east appear to have a better shot at precip.
321 PM EDT WED AUG 17 2016 The weather pattern over GA remains under the influence of a southwesterly flow aloft due to an upper trough just west of the MS river valley and an upper high centered over Bermuda. SBCAPE will remain in the 1500-2000 J/kg with max temps a few degrees above normal in the low to mid 90s.
Weakening upper ridge and increasing moisture will allow for better thunderstorm coverage the next few days with the highest coverage occurring across the north as the upper ridge is squeezed southward.
High pressure ridging across the gulf will maintain a light to moderate southerly flow into the new week.
Broad upper-level trough will begin to shift farther east over the forecast area Thursday. Models have been hinting at precipitation to occur over the eastern portion of the forecast area Thursday afternoon where higher instability is progged to reside while the trough axis shifts east.
High pressure is creeping its way south along the east side of the Continental Divide, and will start seeping through the passes into western Montana this afternoon. A ridge of high pressure rebounds over the Northern Rockies this weekend, causing a warming and drying trend.
Late this evening, a surface cold front will dive southward through the area. Thursday will be significantly more cloudy and cooler than today with highs in the lower 70s.
244 PM CDT WED AUG 17 2016 A mid level trough, that has been hanging out just east of the forecast area the last few days, continues to slowly edge westward today as upper ridging over the SE ConUS builds into SE TX. As a result of increased moisture, lift and instability, showers and thunderstorms continue to affect portions of the Lower Trans Pecos and SE Permian Basin this afternoon. Not completely certain on how far west the upper trough axis will shift by tomorrow but for now, best chances look to be along and east of a Hobbs to Van Horn line.
140 PM EDT WED AUG 17 2016 GA will remain under the influence of the western Atlantic ridge and a moist tropical airmass. The two main atmospheric features are the moisture plume extending from eastern TX to the New England states and the Bermuda ridge that stays parked over the region through the end of the week. This ridge is beginning to weaken but it will continue to keep the main axis of moisture north and west of our area through Thu Night. This ridge eventually allows the deeper moisture to move into our area Fri Morning and will see increased chances of rain through the weekend.
146 PM CDT WED AUG 17 2016 Temps across the cwa were in the lower 90s with dewpoints between 65 and 70 degrees. Much of the sern US is now under an upper ridge, however local radars were showing some sct shra/tsra mainly along the GA/AL border, probably due to orographic or differential heating.
Temperatures running a few degrees warmer than 24 hours ago. Little change in daytime temperatures, maybe a degree or two cooler, with daytime highs 4 to 10 degrees above normal.
Western KS was in the midst of a very weak flow regime in the wake of a trough passage a couple of days ago. That aforementioned trough was moving across the Great Lakes and Ohio Valley region. The lower troposphere was quite dry, by summer standards, and this will be a detriment to organized convective activity.
This would suggest highs 83 to 88 degrees with afternoon heat indices reaching to around or into the low 90s for several hours due to dewpoints to near 70 degrees. Conditions not favorable for severe due to high freezing levels and limited dry air though gusty winds over 30 MPH and brief locally heavy rains supported or typical late summer convection.
Northwest flow aloft will lessen today as an upper ridge builds into the central High Plains. Highs today near previous forecast will range mainly in the lower 90s.
Cloud cover should also be limited by the broad area of subsidence, thus afternoon temperatures should have no problem reaching the upper 80s, with the western counties, including the Kansas City area, reaching the low 90s within an area of greater warm air advection. Differential warm advection will keep areas north of I-70 in the low 90s with areas south in the low 80s.
SHORT TERM (Tonight through Thursday Night): 500mb ridge across the southeast United States extending westward across the northern Gulf coast into south Texas will allow subsidence to continue to increase across the CWA tonight into Thursday.
The resulting weak high pressure overhead was suppressing convection with most storms hugging the higher terrain. Thursday night a cold front will work into the northern forecast area.
The 11 pm EDT regional surface analysis showed a high pressure ridge from the SC coast through central MS. As of 130 am there were still a few, sporadic showers developing along difficult-to-detect mesoscale boundaries, as the lower troposphere remained very moist.
In the meantime, heights begin to fall in the northern tier of states as a strong upper level trough digs southward out of Canada. Highs will be well into the 80s to around 90 with dewpoints in the lower 70s at many locations.
1221 PM CDT WED AUG 17 2016 Outside of one small cluster of weakening thunderstorms over north central Nebraska, most of the convective activity early this morning was located east of the area in association with a more dominant mid level trough. Surface features are forecast to remain rather weak through Thursday and the upper flow transitions from northwest flow to more zonal as a strong upper trough moves out of western and central Canada towards the northern plains.
629 PM EDT WED AUG 17 2016 Weak high pressure builds across the region tonight. A weak upper level trough may bring a few brief showers mainly to the north and mountains Thursday.
An approaching cold front that will bring a chance for thunderstorms to northwest North Dakota this evening otherwise today will be mostly sunny and warm. A cold front will approach northern North Dakota this evening. At this time most models are indicating the highest threat will be across the southern James Valley.
High pressure is over the area early this morning with light winds and mostly clear skies. For today, anticipating mostly quiet conditions as high pressure keeps skies mostly sunny and winds on the light side. Low pressure will develop over western SD and move east-southeast into the evening hours. Frontal boundary will be established early on across the CWA and begin to slide southeast as a cold front as the low begins to push southeast.
Otherwise, temps return to average, if not slightly above average, with maxes ranging from 85-90 for most areas around STL metro and to the north and west, while some thicker high clouds will keep temps down a bit to the southeast of STL metro, with readings in the low-mid 80s. Looking ahead to tonight, persistence mins will be hard to beat with no real change in airmass, maybe a deg or two higher than persistence only because of the higher max temps from previous day: min temps in the upper 60s for most areas. Byrd Dry weather to persist through Thursday night for the most part, then as ridge moves to our east, southerly flow to return once again. Will see increasing moisture and instability ahead of a strong cold front.
210 PM EDT WED AUG 17 2016 High pressure will remain centered well off the coast this afternoon.
A trough spins off the polar vortex and descends south through the Canadian Prairie Provinces, sending a cold front this evening into Northeast Montana. Very warm air that was in place will create unstable conditions when the cold front works it way into the region. The GFS shows a secondary cold front sneaking in from the northwest in late afternoon, which may bring rain showers and possibly thunderstorms.
A well defined upper level low along the New Mexico and Colorado border was continuing to spin slowly to the east and northeast while deeper moisture flow remained to our southeast. On Thursday, we expect the upper low to curl out far enough into the central plains to allow better moisture recovery and easing of the downward forcing over our area.
Today should be similar to yesterday with mostly sunny skies however, mixing will be slightly better today then yesterday so went a degree or two warmer.
138 PM EDT WED AUG 17 2016 Today will be drier and cooler behind a cold front with mainly dry conditions.
557 PM EDT WED AUG 17 2016 High pressure in the Atlantic will shift a little farther eastward and a weak pressure trough will develop in the forecast area today. The trough will become more pronounced Thursday. Convection this afternoon and early evening focused in the Piedmont trough convergence area. A few storms have had elevated strong cores however warm mid level temperatures/upper level ridge axis subsidence area and resulting weaker instability in the Midlands limiting development.
4 inches across the region, with the highest moisture across the coastal plains. Continuing the drying trend Thursday night into the first part of the weekend as mid-level ridging moves farther west.
The upper pattern continues to have a broad upper low pressure trough over the eastern plains, the Bermuda High over the southeast U. Rain amounts will be lower today with the highest amounts over southeast AR.
345 PM CDT WED AUG 17 2016 Mid-afternoon sfc analysis shows high pressure situated over the sern CONUS keeping a very moist mainly srly low-level flow in place over the forecast area. Water vapor imagery shows ridging in place from the wrn Atlantic across the Gulf Coast region along with a weak shear axis just to our west which is helping pull in additional mid/upper-level moisture. Despite the ridging capping is weak. Consensus here is that the models may be relying too much on this ridging building in from the east which is leading to reduced POPs over the next several days.
ridge. Although the ridge has been forecast to develop westward, model guidance has been somewhat inconsistent with the timing and placement of the ridge during the middle and latter part of the week. During the same time period, middle and upper level ridging develops along the northern stream of the split flow across the nation, capping any thunderstorm potential further north after today.
404 PM CDT WED AUG 17 2016 Broad upper level ridging should essentially keep us dry.
1135 AM MDT WED AUG 17 2016 Warm weather will continue today as weak upper-level ridging remains intact over the central Rockies. Water vapor satellite imagery shows a few weak disturbances undercutting the ridge, which combined w/low level convergence along the Laramie Range should promote isolated to widely scattered showers and thunderstorms this afternoon. The ridge should begin to break down on Thu as a weak trough meanders across CO and southern WY.
High pressure will result in hot temperatures for this afternoon. Water vapor imagery continues to show a ridge of high pressure over the eastern Pacific waters with the axis extending southeast into the central Baja peninsula. For Thursday models indicate that the upper low which is currently over the Great Basin will slide to the south to southwest, reaching south central California by late in the day. 2 inches or so through the forecast period, with the highest values approaching 1.
/Issued 351 AM CDT WED AUG 17 2016/ An upper ridge over the Panhandles today will break down and shift east as an upper trough over the central and southern Rockies slowly tracks east Thursday. A mid and upper trough over central and south Texas will move west Thursday advecting abundant low level Gulf moisture into the forecast area from the southeast.
High pressure over the west will keep warm and dry conditions in place through the remainder of the week and into the weekend.
325 PM CDT WED AUG 17 2016 As a subtle mid level trof axis finally moves away tonight, and is replaced by quasi-zonal flow, light showers should end at least temporarily across the entire PAH forecast area, with the possibility of re-development in the southern Pennyrile region late in the night.
230 PM PDT WED AUG 17 2016 A weak low pressure system over California and Nevada will produce isolated afternoon and evening thunderstorms today and Thursday.
Similar to yesterday expect the highest pops and greatest storm coverage again to focus along and to the west of the I-75 corridor during the late afternoon and early evening hours as the convection moves to the west and northwest within the deep layered east to southeast steering flow.
An upper level trof should move into the area this afternoon and should help trigger scattered thunderstorms. An upper level short wave trof will amplify and move across North America this weekend.
High pressure over eastern SD will shift east and set up return flow into the eastern Dakotas this evening as a cold front currently extending from northeast MB through southwest Sask drops south into northern tier CONUS. cold front will drop into far northwest ND this evening, with some showers or convection out ahead of the front reaching the RRV possibly by midnight.
Concur with the GFS deterministic which predicts a weak quasi- stationary upper ridge with approximate E-W axis over the CWA/MSA.
700 PM EDT WED AUG 17 2016 The upper level low will continue to move slowly west from South Florida into the eastern Gulf Of Mexico tonight.
352 PM CDT WED AUG 17 2016 Overall synoptic pattern similar to yesterday, with elongated high sitting over the southeast states and western Atlantic and trough beginning to dig into the Pacific Northwest.
409 PM EDT Wed Aug 17 2016 Dissipating cold front will erode over the Mid Atlantic region tonight.
305 PM EDT WED AUG 17 2016 Upper-ridge across the central NC still nosing its way into the region. Subtropical ridge of high pressure over the Atlantic and the Gulf will keep us near or above normal on temperatures through the weekend.
A weak trough of low pressure will be over the area today. As a trough sharpens over the northern Rockies on Thursday northerly flow will increase and could result in fire weather concerns.
The region will be in between systems on Wednesday as a low pressure system develops across the upper Mississippi Valley.
A weak upper level trough axis will be the focus of much of the rainfall as it lingers along the I30 corridor.
Lows tonight will fall into the lower to mid 70s, upper 70s along the coast and St. 700-300 mb analysis shows mean ridge parked over west central GA with very dry air in a deep easterly flow in this level. The highest storm chances (30-40 percent) will be focused east of Florida Highway 301 during the mid/late afternoon when east coast sea breeze continues its westward track. Max temperatures will top out in the lower 90s (NE FL) to mid 90s (SE GA), with some upper 80s along the coast.
A weak upper level ridge will be found over the area today and into tonight. For tonight, the ridge breaks down just a little but there is not much of a wave that breaks it down. Hot weather will continue into Thursday with highs generally around 90 to the lower 90s.
Stronger push of cooler air still on track for early Thursday with widespread showers and thunderstorms developing.
Look for min temps tonight a deg or two higher than persistence with the higher start from slightly warmer temps today, or readings in the upper 60s most sites. Ditto for Thursday, with max temps a deg or two higher than persistence, favoring the higher MET MOS values, or from the mid 80s south and east of STL metro to around 90 elsewhere.
High-res CAMs show convection currently in higher terrain of Black Hills and Northeastern Wyoming gradually moving toward the east where the higher moisture/instability axis resides. By Thursday morning, cold front will already be in portions of Northwestern South Dakota and Northeastern Wyoming.
Highs thu will range from the lower to middle 90s inland and the upper 80s to near 90 along the immediate coast.
157 PM EDT WED AUG 17 2016 High pressure in the Atlantic will shift a little farther eastward and a weak pressure trough will develop in the forecast area today. The trough will become more pronounced Thursday. The depth of the convection has been limited by a lack of upper level support, suppression from the upper ridge axis, warm mid level temperatures and poor mid level lapse rates.
The upper pattern continues to have a broad upper low pressure trough over the eastern plains, the Bermuda High Pressure over the southeast U. Rain amounts have been lower today with the highest amounts over southeast AR.
254 PM EDT WED AUG 17 2016 Weak high pressure builds across the region tonight. A weak upper level trough may bring a few brief showers mainly to the north and mountains Thursday.
225 PM EDT WED AUG 17 2016 High pressure in the Atlantic will shift a little farther eastward and a weak pressure trough will develop in the forecast area today. The trough will become more pronounced Thursday. The depth of the convection has been limited by a lack of upper level support, suppression from the upper ridge axis, warm mid level temperatures and poor mid level lapse rates.
Thursday: Weak high pressure and drier air will slide into the area for this time period bringing mainly dry conditions.
The weak mid/upper level trough that has been over the top of our area for the last few days remains nearly stationary early this morning, but is still expected to move north/northwestward. Models are in good agreement that this moisture will move north/northwest into the southern 2/3 of our area today as the trough moves.
A sfc cold front moving through the cwfa will also help focus rain chances Sat. Guidance has been somewhat inconsistent on how far to the west the main upper level trough will dig and now the general consensus is for a more progressive/faster system (less digging).
337 PM EDT WED AUG 17 2016 An area of low pressure will pull off to the Canadian Maritimes tonight, with partial clearing expected tonight. Tomorrow a weak cold front will bring an isolated shower to the region.
Models are showing an influence of the upper ridge and limited moisture affecting thunderstorm development in this area. Heaviest rain should be near and along the upper trough/shear axis which is situated near the I30 corridor. There is also a weak sfc reflection in the form of a trough of low pressure near or nw of the I-30 corridor of Northeast Texas into Southwest Arkansas which will be a player in precip coverage today as well.
There remains fairly deep layer ridging across north FL and the southeastern U.
With weak elevated instability, warm air advection, and the arrival of the low level jet across central South Dakota, isolated to scattered showers and thunderstorms will be possible late evening into the overnight hours. On Thursday morning, warm front appears to be situated well to the north of the forecast area. A series of leading short waves will train across the cold front across central South Dakota.
The subtropical ridge will extend across the Gulf Coast states and across south Texas the next 24 hours. Lows tonight will be in the lower 70s, with highs Thursday mainly in the lower and middle 80s.
the intensity of the troughing has diminished. with weaker inverted troughing left over. with the persistent summertime ridge of high pressure re- establishing control.