Aikyam-Lab/Synoptic-Bench huggingface dataset:
113 PM EDT Thu Jun 18 2020 Periodic showers and thunderstorms, mainly during the afternoon and early evening, will be possible through the end of the week as an upper low wobbles slowly eastward. Stacked low pressure will continue slowly lift north and east across the region through the period. Shower coverage should diminish this evening though some cloud cover will remain overnight as the low passes overhead.
1137 AM CDT Thu Jun 18 2020 The region remains sandwiched between an upper ridge across the SW CONUS and an upper low across the Ohio River Valley. Sitting between two troughs, one across the pacific northwest and one over the eastern CONUS, leaves our area under ridging. This low will begin to transition to the northwest and into the Ohio River Valley today with the ridging expanding further towards the east. This will limit the precipitation potential across the area for Thursday, however, there is still a chance that we could see some showers and thunderstorms develop on the peripheral of the ridge. A for temperatures, look for highs in the lower 90s for Thursday across the region. For Friday, afternoon highs will be a degree or two warmer than Thursday across the area.
The CWA will be influenced by west to northwest flow aloft between low amplitude ridging over the western CONUS and troughiness over the central and eastern CONUS.
/issued 1137 AM CDT Thu Jun 18 2020/ The region remains sandwiched between an upper ridge across the SW CONUS and an upper low across the Ohio River Valley. Sitting between two troughs, one across the pacific northwest and one over the eastern CONUS, leaves our area under ridging. This low will begin to transition to the northwest and into the Ohio River Valley today with the ridging expanding further towards the east. This will limit the precipitation potential across the area for Thursday, however, there is still a chance that we could see some showers and thunderstorms develop on the peripheral of the ridge. A for temperatures, look for highs in the lower 90s for Thursday across the region. For Friday, afternoon highs will be a degree or two warmer than Thursday across the area.
The upper level high pressure ridge is expected to flatten somewhat over the region Friday/Friday night, as an upper level trough enters the Plains (deterministic runs.
Upper level low pressure over the Central Appalachians will drift slowly to the NE during the next several days. 5 of an inch higher than the region from the Lower Susq Valley to the NW Mtns of the state. Elsewhere, QPF will average less than 1 tenth of an inch in most locations overnight given the scattered nature of showers ahead of the approaching upper low. Min temps tonight under variable amounts of clouds early on, followed by some stratus forming late (especially in areas that received rain), will vary from the upper 50s across the mtns, to the mid 60s in the Lower Susq Valley. The upper low will continue to slowly weaken as it drifts NE across the Mid-Atlantic region.
315 PM CDT Thu Jun 18 2020 Mid-afternoon sfc analysis continues to show a weak trof bisecting the forecast area, otherwise high pressure remains predominant. Water vapor imagery shows the cutoff low meandering over the mid- Atlantic region, maintaining a nrly flow aloft over the region, while weak ridging is noted to our west. Rain chances look really slim tomorrow as the ridge is progged to slide ewd, effectively putting a cap on an convective development. Maxes should run a degree or so warmer than today under increasing subsidence aloft.
High temperatures will return back to cooler than normal values, with mid 70s to lower 80s.
Showers and thunderstorms continue through the night supported by a strengthening low level jet and enhanced moisture transport intersecting the surface cold front as it slowly progresses south and east. Model solutions quickly begin to diverge on precipitation chances tomorrow, likely due to difficulties resolving the evolution of convective activity overnight and the implications on where the cold front may stall out.
343 PM CDT Thu Jun 18 2020 A slow moving cold front was located over western Minnesota this afternoon. Meanwhile, a short wave trof was co-located with the front. As the afternoon progresses, a stronger upper level short wave trof will move into western Minnesota, pushing the cold front eastward. The cold front moves through northeast Minnesota this evening, and much of northwest Wisconsin overnight. High pressure builds into northeast Minnesota behind the front. Dry elsewhere as the high pressure moves farther east across northeast Minnesota and into northwest Wisconsin. The high remains in place over the rest of the region.
This line picked up in intensity around noon prior to its passage over the Lower and Middle Keys. Otherwise, a weak low level ridge axis remains parked over the region, leading to light southeast flow across the marine district and island chain.
/GG/ Morning KJAN UA data continues to show dry air in the lower levels and warm air aloft which should keep western portions convection free for another afternoon. To the east, KBMX was not as dry in the lower levels and somewhat cooler aloft being in better proximity to the persistent mid level cold core low spinning over the OH valley. The mid/upper low that doesn't end has now shifted over the Mid Appalachians and continues to serve the dual purpose of channeling drier mid/upper level air southward along the Mississippi River Valley while also providing the impetus for limited shower activity in areas closer to the low itself.
Cyclonic flow and cool temps aloft will support some diurnal development as surface temps warm to the low 60s, so expect scattered showers into the evening, especially in our west and south. JKL Northwest flow aloft over the region this morning as elongated upper level low spins over western Manitoba.
146 PM MDT Thu Jun 18 2020 Cold front is moving through northwest part of the forecast area early this morning and will continue to push southeast, clearing the area by 15-18z. High temperatures today will be much cooler than they have been in quite some time, upper 70s to lower 80s, which is slightly below normal. Light showers will linger through Friday morning, then pick up again Friday afternoon and especially Friday night as the main trough axis finally moves across the area.
217 PM CDT Thu Jun 18 2020 An upper level ridge was over our area early this morning between a cut-off upper level low over southern West Virginia and a northern stream upper level trough over the Northern Rockies. The upper low will move slowly northward into eastern Ohio later today and tonight. Some cloudiness may rotate into southwestern IL today on the backside of the upper low, but it appears that any precipitation associated with this feature will remain east of the forecast area.
19Z observational analysis shows a surface cold front from roughly Marshall to Sioux Falls to Yankton. Skies will clear from west to east overnight and with light wind and a cooler post-frontal airmass, expect nighttime lows mainly in the 50s. It will also be noticeably more comfortable with highs near normal (upper 70s to lower 80s) and dewpoints in the lower to mid 50s.
Convection Friday afternoon will be a little harder to come by as the mid level low moves a little further away allowing deeper subsidence from approaching ridge to spread further east. Ridging aloft and dry air holding on in the lower levels will allow for a warmer day Friday as highs top out in the lower 90s, but low relative humidities will keep heat indices near actual temperatures.
Meanwhile, in the mid and upper levels, there is a weak trough to our north and northwest. Going forward, the aforementioned upper level trough will slowly lift out of the region through Friday night. By this weekend, the upper level flow will become zonal, while the low level ridge axis lifts northward.
Showers and thunderstorms continue to slowly make their way mainly over south and central locations of the Sunshine State as upper level trough continues to lift north.
For today, a rather cool day is on tap with chilly air working into the area behind aforementioned cold front. Aforementioned upper low lingers around Manitoba/Ontario through the weekend, possibly into the start of the upcoming work week, though models are struggling with the timing and path of its departure. Precipitation chances should diminish when the low departs.
Morning KJAN UA data continues to show dry air in the lower levels and warm air aloft which should keep western portions convection free for another afternoon. To the east, KBMX was not as dry in the lower levels and somewhat cooler aloft being in better proximity to the persistent mid level cold core low spinning over the OH valley. The mid/upper low that doesn't end has now shifted over the Mid Appalachians and continues to serve the dual purpose of channeling drier mid/upper level air southward along the Mississippi River Valley while also providing the impetus for limited shower activity in areas closer to the low itself.
1028 AM CDT Thu Jun 18 2020 After a rather chilly start for late spring with night time low temperatures ranging in the mid 50s to around 60, warmer conditions are being realized across the greater Tennessee Valley. An unseasonably cool upper low now centered over the KY/WV border was continuing a northern flow across the forecast area. There is enough moisture to support isolated showers and thunderstorms, as temperatures warm into the low/mid 80s. Despite a presence of the low (and with it shifting more to the NE), have inched up high temperatures a degree or two to account for this.
Expect more coverage of showers and storms on Friday especially over southern zones due to the approach of an upper trough and and increase in moisture from the south.
Low level moisture begins to increase Friday night and sfc dew points look a bit higher so raised MinT values into the low/mid 70's.
A weak upper level ridge will remain in place over the region for the next couple of days.
Currently, an upper level low remains situated over southern Canada, with a cyclonic upper flow situated over the forecast area. An impulse moving through the low is producing showers over eastern Montana into western ND. Our given guidance is giving mid to upper 30s over southwest ND tonight, which is on the low end of the envelope of solutions, we did lower temps just a bit over some of our favored cool spots in the southwest. Late in the day, or in the evening we'll see clouds and rain chances increase in the west as another impulse swings around the base of the upper low, into the forecast area.
Expect cooler northwest breezes for the rest of the day with caa cu across the western cwa moving east. High pressure will approach this evening behind the exiting frontal boundary, and will settle in over the region tonight and Friday, bringing a return to dry conditions. Highs on Friday will be in the lower to mid 70s.
245 PM MDT Thu Jun 18 2020 The latest water vapor images show an upper low over Saskatchewan/Manitoba with another over the Southeast U. The cooler northwest flow has shunted the high surface dewpoint air to the southeast, with surface dewpoints mostly less than 50F.
Upper low is slowly working its way northward after moving slightly west earlier this morning. By tomorrow, the upper low will be near the eastern Great Lakes, and we will be on the backside of the trough axis.
Pattern Synopsis/Forecast: Weakening upper ridge axis stretches from Texas up across the northern Great Lakes and into Canada, downstream from sharp troughing very slowly pressing across the northern Plains into the Upper Midwest. Weakening cutoff low has migrated into West Virginia producing clouds/showers and cooler weather across the mid Atlantic into the Ohio Valley. Larger scale ridge axis will remain intact across northern Michigan through Friday as weakening cutoff low migrates northward into Pennsylvania and upstream troughing very slowly advances into the Upper Midwest. Overnight lows will run just a tad warmer than last night. Daytime highs Friday should run a little warmer yet.
A cold front has pushed across a majority of the Oklahoma Panhandle. With the expected cloud cover and some precipitation, Friday's high temperatures should be noticeably cooler.
Warmer today and again Friday. Isolated showers and thunderstorms will develop this afternoon across the higher terrain of central Idaho and northeast Oregon.
The second is further northwest with the true push of colder air into the region, with temperatures over northwestern ND in the low 50s this afternoon. Later tonight, advection of cooler and drier air into the region, along with decreasing clouds, should allow lows to drop into the 40s and 50s. Temps on Friday will be even cooler than today, in the upper 60s to mid 70s even with plenty of sunshine.
As the upper level trough axis shifts east of the Rockies tonight into tomorrow, surface moisture will be reinforced throughout the day tomorrow. Synoptic scale ascent is expected to increase late Friday as a weak impulse over northern Mexico is ejected through the southern High Plains as a larger-scale upper trough lifts by to the north.
115 PM EDT Thu Jun 18 2020 Periodic showers and thunderstorms, mainly during the afternoon and early evening, will be possible through the end of the week as an upper low wobbles slowly eastward. Stacked low pressure will continue slowly lift north and east across the region through the period. Shower coverage should diminish this evening though some cloud cover will remain overnight as the low passes overhead.
This activity continues to be associated with the same upper level low that's been influencing our weather the past few days. Tonight into tomorrow, the low starts to lift and slowly exit to the NE and be over western PA as short wave ridging begins to build in from the west. While the upper low will be moving away, there's still 20 to 30% PoP along and east of I-65. Temperatures are warmer, reaching the middle to upper 80s tomorrow afternoon. Hot and mostly dry weather will start out the weekend as upper level ridging builds in from the west.
Starting tonight and into tomorrow, an upper level trough will move through the area and bring some convection to the region. Models highlight some light precip forming along the leading edge of the trough starting around midnight for eastern. Between noon and 3pm, the trough will have moved to the Front Range as a few residual showers persist over the area. Having said that, a ridge of high pressure will start building into the western U.
and Friday High pressure will continue to influence the weather across northeast Wisconsin as a low pressure system slowly approaches from the west. Tonight and Friday get a bit tricker with respect to precipitation chances as all of the models have halted the onset of precipitation by several hours as the high continues to pump dry air into the western Great Lakes, which is slowing down the progression of the low approaching from the upper Mississippi Valley. Even when the cold front does make it over the region, the NWP and CAMS models weaken the convection as it tracks through the western Great Lakes region. Lows tonight will be warm, as temperatures only fall into the lower to middle 60s. Temperatures on Friday will be a bit cooler across central and north-central Wisconsin with more cloud cover and precipitation.
High pressure is continuing to weaken and move eastward across the Midwest this evening, which will keep conditions dry and winds light through Friday morning. A slow moving cold front will begin to move into Wisconsin Friday afternoon before stalling over south central Wisconsin.
330 PM EDT Thu Jun 18 2020 Persistent closed upper low continues its slow drift north into the central Appalachians/eastern Great Lakes region through the forecast period.
An upper level low will push drier air into the area overnight while a weak surface inverted trough passes over the area. Temperatures could be a bit tricky tonight, with some already cooler pockets from the increased rainfall.
848 PM CDT Thu Jun 18 2020 The showers and thunderstorms that have developed due to daytime heating and lift from the upper level low anchored up in OH and WV will continue to diminish over the next hour or so. Overnight lows will be in the low to mid 60s. The upper low towards daybreak Friday should be heading northbound over SE Ohio, should move NNE to across western PA by the early evening. Despite this low moving further away, residual cooler air aloft and instability from daytime heating will bring more isolated, mainly afternoon showers and thunderstorms. With the upper trough further displaced to the NE, high temperatures to end the work week should rise into the mid/upper 80s, with a few spots reaching 90. A tad warmer Friday night with lows mostly in the mid 60s.
Late tonight and Friday, thunderstorms will be possible, especially in eastern Iowa, where the cold front will be in place during the day Friday. Storms should move east/northeast in the flow east of the approaching upper trof, thus some repeat rains may occur, and swaths of rainfall over 1 inch are likely. Highs will be cooler along and behind the front's position at 10 AM, with lower 80s west and upper 80s near the Mississippi and east/south.
Isolated convection still roaming my southwest early this evening around the cyclonic circulation and deep layer moisture associated with upper low over WV. Elsewhere, QPF will average less than 1 tenth of an inch in most locations overnight given the scattered nature of showers ahead of the approaching upper low. Min temps tonight under variable amounts of clouds early on, followed by some stratus forming late (especially in areas that received rain), will vary from the upper 50s across the mtns, to the mid 60s in the Lower Susq Valley. The upper low will continue to slowly weaken as it drifts NE across the Mid-Atlantic region.
404 PM CDT Thu Jun 18 2020 Last minute adjustments were made to reflect diurnal convection this afternoon, enhanced by weak vorticity associated with the closed low centered over West Virginia.
Friday should be mostly sunny across the cwa with cooler than normal temperatures with highs in the 70s. The upper pattern will be dominated by slow moving cut off upper low system that lingers along the Canadian border.
Deeper moisture will reach farther north across east central Florida with central portions of the forecast area looking to be a favored area for the highest coverage of afternoon storms. Will have POPs in the high likely range over much of the area with PWATs from 2. An UL trough (remnant of the earlier cutoff low north of the state) will ease away from the region.
Otherwise, expect convection to gradually diminish through the evening with high pressure off the Eastern Seaboard maintaining light/variable to easterly flow overnight, with lows in the upper 60s across the upper Nature Coast and 70s elsewhere. Showers and thunderstorms continue to slowly make their way mainly over south and central locations of the Sunshine State as upper level trough continues to lift north.
Warmer and somewhat drier weather is expected for the weekend but there will be day to day chances for afternoon showers and thunderstorms.
/Issued 406 PM CDT Thu Jun 18 2020/ As of this writing, a surface cold front was draped across the forecast area in a southwest to northeast fashion this afternoon roughly along the highway 60 corridor. On Friday and Friday night, the cold front will likely hang around the area, or possibly push even further south. Max temperatures Friday will be strongly dependent on cloud cover and frontal boundary location, with bust potential possible should the cooler METMOS and MAVMOS values verify.
437 PM MDT Thu Jun 18 2020 The latest water vapor images show an upper low over Saskatchewan/Manitoba with another over the Southeast U. The cooler northwest flow has shunted the high surface dewpoint air to the southeast, with surface dewpoints mostly less than 50F.
Isolated showers still in the picture for the overnight as cyclonic circulation and deep layer moisture associated with upper low over WV rotate into the region. Min temps tonight under expanding stratus will vary from the upper 50s across the mtns, to the mid 60s in the Lower Susq Valley. The upper low will continue to slowly weaken as it drifts NE across the Mid-Atlantic region.
Currently, the cold front is located just NW of Harper County into SW KS. A cold front has pushed across a majority of the Oklahoma Panhandle. With the expected cloud cover and some precipitation, Friday's high temperatures should be noticeably cooler.
An upper low to the east will continue to slowly rotate and contribute to isolated showers overnight. With the upper low continuing to rotate scattered showers into the area, kept a brief VCSH mention for the first couple of hours but as we begin to lose heating, these will begin to fade away. Confidence is still on the lower side but was high enough to mention prevailing MVFR BR at TYS and IFR at TRI. AD Chattanooga Airport, TN 65 85 66 89 68 / 30 20 10 10 10 Knoxville McGhee Tyson Airport, TN 63 83 64 87 66 / 30 30 20 10 10 Oak Ridge, TN 63 83 63 87 65 / 20 40 10 10 10 Tri Cities Airport, TN 60 78 60 83 61 / 30 50 30 40 20.
As a weak inverted trough forms over the area, there could be occasional showers, especially over coastal SE GA through the late evening/early morning.
406 PM CDT Thu Jun 18 2020 As of this writing, a surface cold front was draped across the forecast area in a southwest to northeast fashion this afternoon roughly along the highway 60 corridor. On Friday and Friday night, the cold front will likely hang around the area, or possibly push even further south. Max temperatures Friday will be strongly dependent on cloud cover and frontal boundary location, with bust potential possible should the cooler METMOS and MAVMOS values verify.
314 PM MDT Thu Jun 18 2020 Showers and thunderstorms have developed along a line from Breckenridge to Fredrick this afternoon. This trough will move over our area from west to east throughout the daytime hours tomorrow providing strong QG ascent.
Axis of higher moisture will remain from the western Gulf into the lower and middle Texas coast tonight into Friday morning with precipitable water values from 1. This will aid in lift by Friday morning along with the low level convergence zone along the coast. A weak mid level trough axis from the Lower Texas coast northward into the inland Coastal Bend could interact with high moisture to provide isolated to scattered convection again over the coastal plains on Friday.
1040 PM EDT Thu Jun 18 2020 Water vapor imagery highlights a long wave trough axis across the southeastern United States and the Gulf of Mexico. The 00Z RAOBS across the Southeast indicated higher heights at 500 and 200 mb and a filling trough axis. Closer to home, no change in heights at MFL and KEY, although 200 mb heights rose a little as ridging builds north out of the Western Caribbean.
/issued 330 PM EDT Thu Jun 18 2020/ Persistent closed upper low continues its slow drift north into the central Appalachians/eastern Great Lakes region through the forecast period.
Last minute adjustments were made to reflect diurnal convection this afternoon, enhanced by weak vorticity associated with the closed low centered over West Virginia.
Increased upper level ridging building into the area tomorrow should keep a lid on convection with only SCT fair weather CU developing through the afternoon. /issued 315 PM CDT Thu Jun 18 2020/ Mid-afternoon sfc analysis continues to show a weak trof bisecting the forecast area, otherwise high pressure remains predominant. Water vapor imagery shows the cutoff low meandering over the mid- Atlantic region, maintaining a nrly flow aloft over the region, while weak ridging is noted to our west. Rain chances look really slim tomorrow as the ridge is progged to slide ewd, effectively putting a cap on an convective development. Maxes should run a degree or so warmer than today under increasing subsidence aloft.