Aikyam-Lab/Synoptic-Bench huggingface dataset:
349 AM CDT Wed Sep 29 2021 A mean mid/upper trough remains situated across much of the Rockies and Central Great Basin area while weak southerly/southwesterly mid/upper flow prevails over the Central Plains. A narrow mid/upper ridge axis remained situated from the Southeastern U.
This high is not only providing us with the dry air but also the enhanced pressure gradient. This high pressure will remain in place through the end of the week as it becomes reinforced by a Canadian High dipping down from eastern Canada.
A highly amplified upper level trough over the western states will slowly slide east through the period with weak upper ridging continuing to the east.
216 AM CDT Wed Sep 29 2021 The main forecast challenge will be rain/convective chances over the next several days, as the hot/dry pattern this past month transitions to a cooler and wetter one. A frontal boundary will push into the High Plains on Thursday, with increasing warm advection over our area ahead of the front setting off convection that will spread into the region.
323 AM EDT Wed Sep 29 2021 High pressure over the Mid Atlantic states is still dominating our weather pattern. This will continue to give us drier and slightly cooler conditions across west central Florida with most of us staying dry at least through Thursday.
407 AM EDT Wed Sep 29 2021 Dry high pressure will persist through the short term. The high amplitude upper ridge will keep us in a stable northwest flow aloft.
1008 PM CDT Tue Sep 28 2021 Another seasonably warm day across the region as breezy south/southeasterly winds work to mix down warmer low/mid level temperatures. A fair amount of the daytime hours may end up being relatively quiet as deep troughing to our west slowly progresses eastward. Better vort lobe begins to lift northeastward and interact with advancing cold front across areas west of the James River by late afternoon and should result in scattered showers and storms. The main vorticity center to our west is slow to lift north as the overall trough begins to contract.
300 AM EDT Wed Sep 29 2021 High pressure will maintain dry and seasonable conditions for the remainder of the week.
Temperatures and humidity also remain on the high side as mid to upper level ridging continues to prevail over our area.
This surge in moisture is fueled by an eastward moving upper ridge axis that will remain centered over much of the MS River Valley today. At the sfc, high pressure centered east of the Valley will be pushed further eastward, and the moisture axis will drift into the northwest half of the forecast area. A quick look at sfc obs indicates that the high- res models are already underdoing the moisture quality a bit, so decided to stick close to model blends for today. Overnight lows will be on the warm side, only dropping into the low to mid 60s. A closed upper low will begin to drift south out of Quebec and into the northern Atlantic Coast states, and this will work to push cooler, drier air south over the Appalachians.
244 AM EDT Wed Sep 29 2021 A cold front will cross the local area through early Wednesday morning.
The main show will be a late Wednesday night through early Thursday MCS along a cold front diving south.
After two days of record autumnal heat, high temps will be perceptibly cooler under the increased cloud cover. The rain and associated front's progress east is impeded by a bit of a blocking ridge so those rains will be slow to exit the CWA on Thursday night.
1010 PM CDT Tue Sep 28 2021 Another quiet night and day as ridge gradually passes. Flow on back side of ridge should keep winds up a bit tonight but the usual valleys, especially in Wisconsin, will see decoupling and hence, the risk for patchy valley fog once again. Tomorrow looks like one of the warmer days of this stretch with +2. Highly amplified flow is forecast to break down later in the week as upper trough over central Rockies gradually shifts to the northeast.
Otherwise, expect scattered showers overnight mainly east of Billings in the vicinity of a cold front. To the west, sharp pressure rises are observed behind the cold front. Slightly better odds for rain showers tomorrow morning and afternoon as an upper low over Colorado slowly pushes more moisture into the area, but regardless, rain amounts will still be minimal. Vertz A dry airmass returns Thursday as the upper-level trough exits to the east. Temperatures will remain in the lower 70s for most of the area and the 60s for higher elevations.
This evening, widespread thunderstorms are expected to develop to our west along a cold front stretching from northwest Kansas through the Sandhills. Thursday will be a noticably cooler and cloudy day in the post- frontal airmass.
101 AM EDT Wed Sep 29 2021 Building high pressure will return dry and seasonable conditions for the remainder of the week. These clouds were associated with vorticity advection around the western side of a NE CONUS trough. Our area will be in a northwest flow regime aloft, placed between slow- moving upper level low pressure over the northeast CONUS/Canadian Maritimes, and a ridge building from the Gulf Coast through the Mississippi Valley and into Canada. While the upper low will continue to meander over far eastern Canada into the weekend, the ridge to our west will slowly break down and flatten.
401 AM EDT Wed Sep 29 2021 High pressure over southern Ontario will offer warm and dry weather today.
In the lower levels, surface ridging continues to weaken across the SE US as a front sags SWD across E Conus/Mid Atlantic States.
On the other side, temperatures are slightly cooler, in the upper 50s. Overall, today's weather will be strikingly similar to yesterday's, with areas on the warm side of the boundary reaching the upper 80s and else where in the low to mid 80s. Strong subsidence associated with the ridge aloft will remove any chances of precipitation even in the presence of modest lift along the boundary. The boundary should slowly become more vertically oriented during the day as some CAA to the east build high pressure over the Mid- Atlantic, and the mid level winds turn more northerly. The influence of upper level ridging will still hold strong tomorrow, once again removing any rain chances.
Based on current obs and dew point depression, believe TRI has the highest probability of direct impacts at the terminal, so continued with MVFR vis at TRI with mention of BCFG with the airfield along Boone Lake. JB Chattanooga Airport, TN 86 63 85 63 84 / 0 0 10 0 10 Knoxville McGhee Tyson Airport, TN 84 61 85 60 83 / 0 0 0 0 10 Oak Ridge, TN 85 61 84 60 82 / 0 0 0 0 10 Tri Cities Airport, TN 83 55 83 53 81 / 0 0 0 0 10.
320 AM EDT Wed Sep 29 2021 A cold front will cross the local area through early Wednesday morning.
Still expect temps to top out in the upper 70s to the lower 80s across the Bluegrass this afternoon with lower 80s out across the I- 65 corridor. Temperatures this evening should fall steadily in the upper 60s and should be in the lower 60s by midnight.
224 AM CDT Wed Sep 29 2021 A fairly amplified upper level pattern was in place over the CONUS with a ridge axis across the central U. and trough axis over the western U. Several waves of energy were noted within the western trough to the southwest of our CWA, with the closest one in Oklahoma, which was aiding in some scattered convection. The increase in cloud cover and scattered rain will keep temperatures cooler than we've had the past several days with highs from the low to mid 80s over the area.
A strong ridge at 500mb and southerly flow ahead of the approaching trough continues to support the advection of moisture into the region. Wednesday will see an increased coverage of isolated shower/t-storm activity that will keep high temperatures in the low to mid 80's across the CWA. High temperatures on Thursday will be in the upper 70's across the mountainous regions of the CWA while in the lower 80's elsewhere.
331 AM EDT Wed Sep 29 2021 A closed low system will draw south today from Quebec into New England while ongoing amplification of a trough across the Four Corners region eventually closes off late Wednesday into early Thursday.
A few showers are possible this morning over the Atlantic waters south of the Cape, where there is enough moisture beneath the low- level inversion to support convection. Ridging will steadily become less dominant during the period with a continuation of easterly flow. Incrsg moisture underneath the weakening ridge will prompt development of some marine based showers by Fri with some of the activity brushing the coastal areas.
SHORT TERM (Now through Thursday): 500mb ridging centered over the western Gulf of Mexico into the southeastern U. while a large mid level trough with a series of disturbances swings from west to east over Texas through the period.
The trough west of the area this morning will lift northward across Kansas today. Better chances for more widespread rainfall will arrive on Thursday as a mid-level trough becomes cutoff over the Four Corners and a surface boundary moves into central Kansas. Total rainfall today through the weekend is currently forecast to range from one to two inches across northeastern Kansas, with the higher amounts most likely occurring toward north-central Kansas.
322 AM EDT Wed Sep 29 2021 SHORT TERM (Today through Thursday): Surface ridging emanating from the coastal Carolinas continues to advect a drier airmass over the region. Seasonably cooler temperatures in the mid/uppers 80s and slightly lower dewpoints in the upper 60s/lower 70s will allow for much welcomed "cooler" conditions (by South Florida standards).
High pressure was located across Michigan into western Ontario early this morning with low pressure over southeastern Saskatchewan. A cold front trailed into the western Dakotas and the Rockies with another stationary boundary stretching across the Missouri and Ohio Valleys. The area of high pressure will drift off to the east for today and tomorrow as the front in the western Dakotas slowly meanders eastward into the Red River Valley. Stout upper ridging will remain in place across the Mississippi Valley and make it difficult for the front to move east with little in the way of upper level support.
This will be a result of the strong UL large scale ridging across the central US. Otherwise we will continue to see the large scale ridge dominate the region. Into Thursday and Thursday night the ridge will slowly start nudging east and breaking down.
With ample sunshine and boundary layer flow becoming more southerly, high temperatures will be a couple of degrees warmer than yesterday. Lows tonight will be in the lower to middle 60s.
247 AM EDT Wed Sep 29 2021 Synopsis/Discussion/Aviation/Marine - Upper ridging breaks down late week with chance of rain over the weekend Blocking pattern this week with upper low across the NE CONUS and ridge axis near the central Great Lakes. The ridge breaks down late week with some moisture return beginning as the high moves further east.
203 AM MDT Wed Sep 29 2021 Morning satellite imagery shows a trof lifting thru northwest MT and a southern split wave over the northern great basin. That being said, surface cold front has pushed through our entire cwa.
1127 PM EDT Tue Sep 28 2021 Building high pressure will return dry and seasonable conditions for the remainder of the week. These clouds were associated with vorticity advection around the western side of a NE CONUS trough. Our area will be in a northwest flow regime aloft, placed between slow- moving upper level low pressure over the northeast CONUS/Canadian Maritimes, and a ridge building from the Gulf Coast through the Mississippi Valley and into Canada. While the upper low will continue to meander over far eastern Canada into the weekend, the ridge to our west will slowly break down and flatten.
Otherwise look for cool temperatures in place following the recent cold frontal passage.
314 AM CDT Wed Sep 29 2021 Another warm day is in store as strong H5 ridging slowly pushes to the east. An upper low will gradually work into the Northern Plains by the late afternoon, bringing a chance for showers and thunderstorms to the CWA beginning early this afternoon. As such, highs should be able to reach the lower 80s before cloud cover moves into the area by midday. Cooler temperatures gradually work into the area Thursday from west to east as our H5 low weakens and slowly moves to the east.
Similar pattern will continue into tomorrow bringing warm temperatures to the region with the exception that the North Shore will see temperatures in the low to mid 60s.
Drier and warmer conditions are forecast for the weekend with a return to more seasonable fall weather. A deepening trough and associated cool front will move through southern Utah and into Arizona tonight and will then remain over Arizona through Thursday night. Daytime temperatures will cool further for Wednesday and Thursday with the trough passage and additional cloud cover.
By late tonight, a cold front will approach northwest Oklahoma with increasing probabilities for convection.
431 AM EDT Wed Sep 29 2021 Despite the fact that a cold front will move through the region, the short term period will be very uneventful. The "backdoor" front is losing momentum as its supporting trough aloft continues to shift eastward and ridging aloft builds into our area from the west. This will be short lived, as an upper level amplified pattern is present, with troughing along both the east and west coast.
250 AM CDT Wed Sep 29 2021 A skinny upper ridge will get squeezed between troughs over the western half of the country and the northeast through Thursday. A weak upper disturbance will lift north from the lower Mississippi Valley today through Missouri Thursday.
136 AM EDT Wed Sep 29 2021 Warm weather will continue even as a weak cold front pushes through on Thursday. After a few cooler nights during the late week period warmer weather will return.
Upper-level low pressure will drop southward to a position over New England on Wednesday. High temps in the low to mid 60s across the mtns and upper 60s to around 70F in the Susq Valley will be a few deg F shy of normal. With winds dropping off, mins will drop to the lower 40s over the northern and western high terrain, and mid to upper 40s elsewhere, along with river valley fog late at night into early Thursday morning.
1222 AM CDT Wed Sep 29 2021 Currently dealing with a mix of VFR and MVFR ceilings across our airspace attm with the low clouds quickly advancing northward across NE TX into NW LA. /issued 934 PM CDT Tue Sep 28 2021/ Upper-level trough across central and west Texas into Colorado continues to support a convective complex across central Texas.
Models keep most of the area dry during the day on Wednesday so have scaled back PoPs accordingly, with the highest rain chances mainly across the eastern half of the area.
1154 PM CDT Tue Sep 28 2021 Dry and unseasonably warm conditions will continue through late week before a frontal system brings widespread rainfall and cooler temperatures by the weekend. High pressure and synoptic subsidence will help to provide clear skies with light winds overnight. Persistence isn't a bad forecast for Wednesday as a similar air mass will be in place beneath a pronounced upper-level ridge. Overnight lows will cool into the lower 60s as clouds begin to increase.
308 AM CDT Wed Sep 29 2021 Highly amplified upper ridge remains parked over the Mississippi Valley early this morning, with its axis slowly drifting eastward today. Certainly an anomalous ridge by late September standards with 500mb heights sitting near the 99th percentile per NAEFS, though temperatures are expected to remain safely below daily records. The ridge will continue to be nudged eastward tonight by a broad longwave trough spanning the western CONUS. Meanwhile a cold front and accompanying line of convection will be crossing the Northern Plains. The upper ridge, with its axis just east of our area, begins to collapse on Thursday as the upstream trough morphs into a weak closed low over the Four Corners region. That said, models are finally coming into somewhat better agreement on their handling of individual waves as the longwave trough breaks down.
246 AM EDT Wed Sep 29 2021 A cold front will cross the local area through early Wednesday morning.
This will continue to be forecast in many locations, with low temperatures in the lower 60s. A few spots may dip into the upper 50s atop the highest elevations of Lookout Mtn. There are some slight discrepancies among the short range models as to how far east this ridge moves on Wednesday. Latest guidance suggests that the axis of the ridge will bisect the forecast area, with southwesterly flow over our western zones and northwest flow over our eastern zones. The better chances will be on Thursday, when the ridge is expected to weaken and slide further east. Temperatures will be near seasonal norms, with highs in the mid to upper 80s and lows falling into the lower to mid 60s.
Showers and thunderstorms continued early this morning as an upper level trough and jet move across South Central Texas. As an upper level trough drifts east across the Four Corners region tonight into Thursday, upward forcing along with an upper level jet keep low chances of showers and thunderstorms going, then showers and thunderstorms become more numerous in the afternoon as forcing increases along with heating.
Upper- level low pressure over Quebec will drop southward to a position over New England later today. High temps in the low to mid 60s across the mtns and upper 60s to around 70F in the Susq Valley will be a few deg F shy of normal. With winds dropping off, mins will drop to the lower 40s over the northern and western high terrain, and mid to upper 40s elsewhere, along with river valley fog late at night into early Thursday morning.
628 AM CDT Wed Sep 29 2021 A fairly amplified upper level pattern was in place over the CONUS with a ridge axis across the central U. and trough axis over the western U. Several waves of energy were noted within the western trough to the southwest of our CWA, with the closest one in Oklahoma, which was aiding in some scattered convection. The increase in cloud cover and scattered rain will keep temperatures cooler than we've had the past several days with highs from the low to mid 80s over the area.
1046 AM EDT Wed Sep 29 2021 High pressure over southern Ontario will offer warm and dry weather today.
654 AM EDT Wed Sep 29 2021 A weak moisture starved cold front will drop south into South Carolina late today. High pressure will build down from the north behind it Thursday into late week.
Afternoon temperatures will remain cooler than average during much of the forecast. An upper trough axis is currently situated along the western Arizona border extending up toward the north. This is all driven by a deepening of the upper trough as it slowly creeps toward the east. The upper trough axis slowly moves east Thursday night, introducing drier northwesterly flow.
626 AM CDT Wed Sep 29 2021 The leading edge of the cold front can be seen on radar this morning nudging into north central SD and trailing back into the Badlands. So far, all precip is confined behind the front where upper level support increases in a broad upper trough. Other than some lingering mid level moisture in the morning, the effects of the cold front will have exited to the east.
Southerly flow will increase the afternoon around an upper ridge axis, helping to advect some deeper, Gulf moisture into the Tennessee Valley. To our southwest, dense cloud cover and some shower activity was noted across the lower Mississippi Valley, thanks to a weak disturbance along the LA/TX Gulf coast. Overnight lows will be on the warm side, only dropping into the low to mid 60s. A closed upper low will begin to drift south out of Quebec and into the northern Atlantic Coast states, and this will work to push cooler, drier air south over the Appalachians.
/issued 323 AM EDT Wed Sep 29 2021/ High pressure over the Mid Atlantic states is still dominating our weather pattern. This will continue to give us drier and slightly cooler conditions across west central Florida with most of us staying dry at least through Thursday.
BRO radar currently indicates a few light to moderate showers along the lower Texas coast. /issued 340 AM CDT Wed Sep 29 2021/ SHORT TERM (Now through Thursday): 500mb ridging centered over the western Gulf of Mexico into the southeastern U. while a large mid level trough with a series of disturbances swings from west to east over Texas through the period.
715 AM EDT Wed Sep 29 2021 Aviation - Upper ridging breaks down late week with chance of rain over the weekend Blocking pattern this week with upper low across the NE CONUS and ridge axis near the central Great Lakes. The ridge breaks down late week with some moisture return beginning as the high moves further east.
A weak cold front will bring a chance for rain and breezy winds east of the Cascades into the Idaho Panhandle on Thursday.
429 AM CDT Wed Sep 29 2021 The leading edge of the cold front can be seen on radar this morning nudging into north central SD and trailing back into the Badlands. So far, all precip is confined behind the front where upper level support increases in a broad upper trough. Other than some lingering mid level moisture in the morning, the effects of the cold front will have exited to the east.
Another warm day is in store as strong H5 ridging slowly pushes to the east. An upper low will gradually work into the Northern Plains by the late afternoon, bringing a chance for showers and thunderstorms to the CWA beginning early this afternoon. As such, highs should be able to reach the lower 80s before cloud cover moves into the area by midday. Cooler temperatures gradually work into the area Thursday from west to east as our H5 low weakens and slowly moves to the east.
1004 AM EDT Wed Sep 29 2021 A weak moisture starved cold front will drop south into South Carolina late today. High pressure will build down from the north behind it Thursday into late week.
Mean layer ridging remains over Mexico, in addition to a sharp long wave ridge axis extending north to near the Great Lakes. The Florida Keys are along the southern flank of a continental high pressure system parked over the southeastern United States.
Otherwise, weak cyclonic flow aloft is infringing upon a ridge axis centered over the southeast CONUS. The convective activity will be slow to diminish and could linger through most of the evening given continued weak ascent associated with the trough in the very moist airmass.
SHORT TERM (Today through Thursday): Surface ridging emanating from the coastal Carolinas continues to advect a drier airmass over the region. Seasonably cooler temperatures in the mid/uppers 80s and slightly lower dewpoints in the upper 60s/lower 70s will allow for much welcomed "cooler" conditions (by South Florida standards).
414 AM CDT Wed Sep 29 2021 The forecast concerns in the short term will be showers and thunderstorms developing along a slowly advancing cold front this afternoon into tonight. This will interact with a southeast advancing Pacific cold front. Highs today will range from 65 to 75 behind the front across the northwest Sandhills to the low 80s ahead of the front across all of the southeast. 5 inches near and ahead of the slowly advancing Pacific cold front. Temperatures will be much cooler in the upper 60s.
Despite the fact that a cold front will move through the region, the short term period will be very uneventful. The "backdoor" front is losing momentum as its supporting trough aloft continues to shift eastward and ridging aloft builds into our area from the west. This will be short lived, as an upper level amplified pattern is present, with troughing along both the east and west coast.
649 AM EDT Wed Sep 29 2021 A cold front will cross the local area through early Wednesday morning.
625 AM EDT Wed Sep 29 2021 High pressure over southern Ontario will offer warm and dry weather today.