Aikyam-Lab/Synoptic-Bench huggingface dataset:
Mostly sunny skies showing up on visible satellite imagery this morning with just a few clouds mainly in our northeast counties, while surface obs show temperatures in the upper 70s to low 80s and dewpoints in the low 70s. Another hot and humid day is expected as an upper ridge over the Carolinas builds westward into the state.
855 AM MDT Fri Aug 27 2021 It will be a cooler day today, along with scattered rain showers or isolated thunderstorms, with most of the precipitation falling this afternoon.
Highs will be in the low 80s to low 90s. Highs will again be in the low 80s to low 90s.
This parallels the back side mid-level ridging and what seems to be an area of weak confluence and building instability. Maples The Heat Advisory continues today with upper level ridging over the region along with south-southwest winds. Maximum heat indices of 100 to 105 can be expected this afternoon with highs in the low to mid 90s and dew points in the low to mid 70s.
It will be a cooler day today, along with scattered rain showers or isolated thunderstorms, with most of the precipitation falling this afternoon.
Expect another warm night tonight across the region as the upper level ridge remains in place.
A frontal boundary will be in place north of the forecast area and will push off to the northeast as the trough moves through. Temperatures will be near or slightly cooler then yesterday, but will still see highs top out in the 90s. High pressure positioned over the southeastern states will allow for a more easterly flow along the Gulf coast, and will inhibit transport of Gulf moisture northward.
Highs will end up in the lower 90s this afternoon. Overnight, clear skies and light winds will likely promote patchy areas of fog and low clouds again, with lows in the low/mid 70s.
Cooler air aloft has destabilized the atmosphere with showers and thunderstorms redeveloping behind a weak front. This weekend will trend warmer and drier as a quick moving and weak high pressure system transits the Northern Rockies.
Weak upper level high pressure will hold overhead. Southerly winds will continue for much of today, resulting in additional moistening of the lower atmosphere and slightly cooler temperatures compared to yesterday.
109 PM CDT Fri Aug 27 2021 ridge which extends across much of the eastern CONUS into the southern/central Plains strengthens somewhat over the eastern CONUS during the period. For Saturday, with the trend of increasing deep layer moisture along with the enhanced lower level convergence beginning to develop, have gone with likely to categorical pops for much of the area with the higher pops over extreme southeast Mississippi and extreme southwest Alabama where the lower level convergence looks strongest. Lows tonight range from the lower 70s inland to the mid 70s at the coast.
SHORT TERM (Now through Saturday Night): Typical summertime heat and moisture are in place across the CWA today, as evidenced by temperatures currently in the low to middle 90s and PWAT values around 2 inches as indicated by todayâs 12z sounding. Midlevel inverted troughing along with seabreeze interactions at the surface are helping to initiate scattered convection across coastal regions this afternoon. Similar to yesterday, this activity will progress inland with the inverted trough and then diminish by the early evening hours with the loss of solar heating. A fairly similar setup will occur again tomorrow, albeit with a weaker midlevel inverted trough.
GOES-16 Satellite trends this afternoon depict an upper level ridge axis centered off the Carolina coast and an upper level trough axis over the Western United States. KNQA/KGWX WSR-88D radar trends depict isolated showers and thunderstorms mainly over north Mississippi this afternoon with temperatures as of 3 PM CDT in the lower 90s at most locations. For Saturday, convective inhibition will likely decrease, as southeasterly flow increases in the low levels, and precipitable water values increase to around 2 inches. But if temps warm to the lower 90s as forecast, rainfall coverage may be simply delayed a bit.
A trough over western MT and southern Alberta has brought a cold front to the region with northwest flow aloft.
/issued 916 AM EDT Fri Aug 27 2021/ High pressure over the Atlantic and extending southwest along the Mid Atlantic coast combined with Tropical Storm Ida over the northwest Caribbean Sea is supporting an increasing east southeast wind flow over the region early this morning as the pressure gradient slowly tightens over the region. A tightening pressure gradient between high pressure over the Atlantic and extending southwest along the Mid Atlantic coast and Tropical Storm Ida over the Northwest Caribbean Sea will support an increasing east to southeast wind flow and slowly building seas over the Gulf waters the remainder of today.
Upper level analysis places trough over central Montana southward into the central Rockies. Otherwise, main change to the forecast comes in the afternoon/evening hours as trough moves over the area. Chances then wane overnight as the trough pushes east.
S/W trof evident in sat pix over MT will slide east into the western Dakotas tonight. Increasing moisture and instability per forecast HREF MUCAPES is expected ahead of this feature, transported by light to moderate LLJ development across the High Plains this evening. Meanwhile, mid-level winds will be increasing as H5 trof approaches tonight. On Saturday a synoptic scale cold front will be pushing across the CWA, and should be near the eastern border with MN by late afternoon/early evening. This area is where we'll have the highest chances for convection and even severe weather.
Expect quiet conditions to continue through tonight though clouds will be on the increase especially over the Pine Ridge and an isolated shower/rumble of thunder may sneak in from the panhandle to the sandhills ahead of a cold front approaching from the northwest. The cold front will slowly move through Nebraska on Saturday with large scale ascent from favorable position of the right rear quadrant of the upper level jet and a vigorous short wave moving through the Dakotas. Expect improving conditions behind the front after the upper trof axis pushes through and ends any lingering showers/thunder, followed by the arrival of notably cooler air. Development of a trof over the Pacific northwest and arrival of Ida along the central Gulf coast will amplify the ridge over the midwest.
No impacts from Ida will occur this weekend though as an upper ridge over the Carolinas continues to build westward across the state.
1104 AM EDT Fri Aug 27 2021 GOES visible satellite imagery is highlighting generally partly to mostly cloudy skies across the island chain, with scattered clouds in the low-levels underneath a scattered to broken deck of high cirrus clouds. Some of these squalls will attempt to make the trek and reach portions of the Lower and Middle Keys by early afternoon. As Ida continues to push northwestward from western Cuba towards the Gulf of Mexico, these squalls will likely increase in coverage and intensity by this evening, especially in the Lower Keys.
Expect quiet conditions to continue through tonight though clouds will be on the increase especially over the Pine Ridge ahead of a cold front approaching from the northwest. The cold front will slowly move through Nebraska on Saturday with large scale ascent from favorable position of the right rear quadrant of the upper level jet and a vigorous short wave moving through the Dakotas. Expect improving conditions behind the front after the upper trof axis pushes through and ends any lingering showers/thunder, followed by the arrival of notably cooler air. Development of a trof over the Pacific northwest and arrival of Ida along the central Gulf coast will amplify the ridge over the midwest.
The big story is that it will be much more pleasant with cooler highs only around 80 over southern Nebraska, to the lower and middle 80s over north central Kansas. The overall upper level pattern will start out fairly zonal, but we will see a building upper level ridge across the southern plains that will push north into the central plains allowing for a decent warm up through mid week.
333 PM EDT Fri Aug 27 2021 Latest analysis shows high pressure off the SE coast with weaker high pressure over the southern Appalachians. The ridge will build inland overnight through Saturday with rising heights across the local area. With the higher heights and high pressure still in control on Saturday, expecting a mostly dry day with just some widely scattered diurnally driven showers/storms. The weather of eastern Kentucky will likely be active, with influences from the remnants of tropical cyclone Ida, an approaching cold front, and an influx of warm moist air off the Gulf of Mexico expected.
Look for high temperatures to settle into the low to mid 90s for this afternoon.
Evening convection will push into central SD this evening, with elevated convention developing over SW into central SD overnight per the advancing upper trough. Much cooler temps can be expected Sat, esp over NE WY where temps will struggle out of the 60s, esp where clouds persist.
The next short wave trough axis sweeps across the CWA on Saturday with the bulk of the mid-level energy focused across our northern zones during the mid/late afternoon. Upper high that has been in control of our weather shifts east and longwave trough over the west allows systems to move into the area. A stalled out cold front lays across central WYoming this morning.
336 PM CDT Fri Aug 27 2021 Issued at CDT Fri Aug 27 2021 Late this afternoon, an upper trough was located across the central Rockies. A downstream upper level ridge axis extended from the southeast US north-northwest into the southern Great Lakes.
Southerly breezes underneath a broad upper level ridge was ongoing across much of the southern and central Plains overnight.
The upper short wave will exit to the northwest through Saturday afternoon as a ridge builds into the area in its wake.
Long story short is upper level high pressure continues to hold temperatures maybe 5 degrees above normal.
1247 PM CDT Fri Aug 27 2021 A weak area of low pressure will track from north central Nebraska this morning to northwest Iowa by this afternoon. This will drag a weak cold front across the area this morning, but that front pretty much washes out by this afternoon as it moves into eastern Nebraska. The low will migrate east-northeast through the day and be located across far southeast South Dakota by late Saturday afternoon. Appears there is some threat for scattered late afternoon surface based convection along the cold front, which should extend from near O'Neill to Thedford to Sidney by late afternoon.
947 AM MDT Fri Aug 27 2021 Chasing the low clouds and fog around the area this morning to make the grids look semi-reasonable.
(This evening through Saturday) As the upper-level ridge shifts east, and more moisture-laden low-level air is drawn northwest into Oklahoma, daytime temperatures will drop a few degrees, compared to the last few days.
This is consistent with the indications for a weak upper level ridge overhead as well. Saturday, the weakness in the upper ridge is expected to remain overhead.
Did make some minor updates to PoPs for the afternoon with slight chances residing across the higher terrain most likely. Diegan Chattanooga Airport, TN 72 90 72 90 72 / 10 20 10 30 10 Knoxville McGhee Tyson Airport, TN 71 92 71 92 70 / 10 10 0 20 10 Oak Ridge, TN 71 92 71 91 70 / 10 20 10 20 10 Tri Cities Airport, TN 67 92 67 91 67 / 10 10 10 30 10.
A few isolated showers and thunderstorms have developed over mostly the high terrain along the Mogollon Rim and White Mountains as well as over the Chuska Mountains. Coverage is expected to increase becoming more scattered in nature through the late afternoon and into the evening hours, especially in the high terrain of Navajo and Apache counties. A weak ridge remains in place through the weekend, allowing for moisture to slowly creep northward into the high country. Afternoon showers and thunderstorms are expected each day, but with coverage still remaining isolated to scattered across mainly the high terrain.
The high pressure system over the TX Panhandle is going to degrade allowing for heights to fall tomorrow afternoon. Therefore, tomorrow is forecast to be a degree or two cooler.
/Tonight through Friday/ A well defined warm front is across central Iowa this afternoon while a short wave is moving across eastern Nebraska and into central Iowa. A few strong updrafts have developed over the past hour north of the warm front and just ahead of the approaching short wave energy. Backed sfc winds ahead of the warm front have favorable shear profiles and marginally favorable LCLs for a few tornadoes.
Recent CAMs suggest increasing chances for convection from south central into southeast North Dakota after midnight when better mid to upper level forcing rides over the lower level baroclinic zone. Upper level analysis places trough over central Montana southward into the central Rockies. Otherwise, main change to the forecast comes in the afternoon/evening hours as trough moves over the area. Chances then wane overnight as the trough pushes east.
Issued at CDT Fri Aug 27 2021 Late this afternoon, an upper trough was located across the central Rockies. A downstream upper level ridge axis extended from the southeast US north-northwest into the southern Great Lakes.
Very minor adjustments were made to temperatures tonight, weighted mostly toward the blended guidance but manually "bias corrected" slightly toward last night's outcome, which was a degree or two cooler than blended guidance in some locations. BRB (This evening through Saturday) As the upper-level ridge shifts east, and more moisture-laden low-level air is drawn northwest into Oklahoma, daytime temperatures will drop a few degrees, compared to the last few days.
1050 PM EDT Fri Aug 27 2021 A frontal boundary will lift northward across the area as a warm front later tonight and Saturday ushering in a return to sultry humidity levels that will last through the weekend, and also lead to chances of showers and storms both days.
The ridge continues to build northward this evening, which will work to dissipate ongoing convection. H5 ridge position retrogrades this weekend such that the ridge axis becomes nearly located on the spine of the Appalachians. At the surface, broad high pressure remains centered near North Carolina with cold high pressure building off the Northeast US and Canadian Maritimes. The latter will actually send a "backdoor" cold front into Pennsylvania. however, don't look for any truly cooler air as that'll remain displaces farther northeast.
649 PM CDT Fri Aug 27 2021 Widely scattered SHRA and TS will continue to decline this evening everywhere except VCT where additional activity will remain possible through much of the night just north of an upper low. The upper short wave will exit to the northwest through Saturday afternoon as a ridge builds into the area in its wake.
In addition a Denver cyclone was enhancing low level convergence, east of DIA, with a developing line of storms. A closed low over Canada has a trailing trough with with some weak perturbations in the flow pushing across Colorado late tonight and Saturday. The surge that pushes through early Saturday looks to be pretty moisture starved but it will bring a slightly cooler airmass and keep high temperatures in the upper 80s to lower 90s for the plains. This cooler boundary layer will also help to cap the atmosphere for Saturday and keep storms at bay and conditions dry. Saturday night features flat upper ridging for the CWA with an upper trough moving eastward to the north of Colorado. This trough will usher in a cold front Saturday evening.
448 PM MDT Fri Aug 27 2021 Longer-wave H5 trough remains in place across western Canada, with smaller waves rotating around this trough across then northern tier of states. The trough passing to the north will bring a weak cold front southward this evening, bringing increased humidity. Since timing is earlier than peak heating, shower activity will again be minimal, and mainly limited to the Bighorn Mountains, closest to the trough.
Currently, upper level high pressure was centered over the Carolina coast. Hurricane Ida was located over the western tip of Cuba, with guidance continuing to direct Ida around the southwestern edge of the Carolina upper high towards the Louisiana coast. Temperatures are expected to drop into the low 70s northwest of the Alabama River, mid 70s southeast and upper 70s along the coast.
307 PM MDT Fri Aug 27 2021 A closed low over Canada has a trailing trough with with some weak perturbations in the flow pushing across Colorado late tonight and Saturday. The surge that pushes through early Saturday looks to be pretty moisture starved but it will bring a slightly cooler airmass and keep high temperatures in the upper 80s to lower 90s for the plains. This cooler boundary layer will also help to cap the atmosphere for Saturday and keep storms at bay and conditions dry. Saturday night features flat upper ridging for the CWA with an upper trough moving eastward to the north of Colorado. This trough will usher in a cold front Saturday evening.
Rainfall amounts range from a trace to 4 inches with the higher amounts over the coastal parishes.
Another mild and clear night is on tap across the region with lows generally in the low to mid 70s except for a few locations, especially in the northwest Arkansas valleys, that could dip into the upper 60s.
Highs will reach near 90F to the lower 90s across ECFL.
/issued 242 PM CDT Fri Aug 27 2021/ SHORT TERM (Now through Saturday Night): Typical summertime heat and moisture are in place across the CWA today, as evidenced by temperatures currently in the low to middle 90s and PWAT values around 2 inches as indicated by todayâs 12z sounding. Midlevel inverted troughing along with seabreeze interactions at the surface are helping to initiate scattered convection across coastal regions this afternoon. Similar to yesterday, this activity will progress inland with the inverted trough and then diminish by the early evening hours with the loss of solar heating. A fairly similar setup will occur again tomorrow, albeit with a weaker midlevel inverted trough.
334 PM MDT Fri Aug 27 2021 Longer-wave H5 trough remains in place across western Canada, with smaller waves rotating around this trough across then northern tier of states. The trough passing to the north will bring a weak cold front southward this evening, bringing increased humidity. Since timing is earlier than peak heating, shower activity will again be minimal, and mainly limited to the Bighorn Mountains, closest to the trough.
BRB (This evening through Saturday) As the upper-level ridge shifts east, and more moisture-laden low-level air is drawn northwest into Oklahoma, daytime temperatures will drop a few degrees, compared to the last few days.
VFR conditions throughout the period at CHA and TYS as high pressure is in control. SR Chattanooga Airport, TN 90 72 90 72 89 / 10 0 20 10 40 Knoxville McGhee Tyson Airport, TN 93 71 92 71 92 / 10 0 20 10 40 Oak Ridge, TN 92 71 91 70 90 / 20 0 20 10 40 Tri Cities Airport, TN 93 67 92 67 91 / 20 0 20 10 40.
Meanwhile, storms are expected to form over the higher terrain of New Mexico and move southeast towards the FA within northwesterly flow aloft.
Otherwise, expect highs a degree or two cooler than yesterday (88-93 F) due to slight cooling of the 850 mb thermal ridge.
Today will be another hot and humid day as southwesterly flow increases ahead of an approaching cold front. Afternoon highs will once again climb into the low to mid 90s, with heat indicies reaching near 100.
S/W trof evident in sat pix over MT will slide east into the western Dakotas tonight. Increasing moisture and instability per forecast HREF MUCAPES is expected ahead of this feature, transported by light to moderate LLJ development across the High Plains this evening. Meanwhile, mid-level winds will be increasing as H5 trof approaches tonight. On Saturday a synoptic scale cold front will be pushing across the CWA, and should be near the eastern border with MN by late afternoon/early evening. This area is where we'll have the highest chances for convection and even severe weather. An upper trough axis will be pushing east and exiting our area by the time this period gets underway Sunday morning.
A warm front is stretched across the C Plains into the Upper Great Lakes, and into New England. There is a very juicy atmosphere for the day with the warm front moving north, producing expected temperatures in the 80s, and the PWAT is around 1. Ridging centered on the mid-Atlantic extends up into the Lower Great Lakes. At the surface the stationary front from the past couple days will have finally lifted well to our north as a warm front.
A Heat Advisory continues through the day for locations south of the I-74 corridor, as heat index values will peak in the low 100s. A Low pressure system and associated frontal boundary will drop into the Midwest Sunday.
A new batch of thunderstorms will then take shape in the late morning and early afternoon over the high terrain of northern and central New Mexico.
Today we should warm up into the low 90s with the possibility of diurnal showers and thunderstorms. Overnight temperatures will cool off into the low 70s. As for Sunday much of the same with temperatures slightly cooler in the upper 80s and low 90s with diurnal showers and thunderstorms.
Chances for isolated to scattered thunderstorms will increase over the weekend, especially on Sunday as an upper ridge continues to shift west through the Carolinas and east/southeasterly flow results in gradual moisture advection. Will see little change in temperatures over the weekend, as highs range from the upper 80s/lower 90s and overnight lows remain in the low to mid 70s.
At the mid to upper levels, the base of a broad longwave trough will continue to approach western and central North Dakota today. A surface cold front, currently located over western North Dakota, will also progress east through the day. Further west and north, showers and a few thunderstorms will also be possible as the base of the longwave trough moves overhead this afternoon, but instability will be limited here. Behind the cold front, expect highs in the 70s today with lows in the mid 40s to mid 50s tonight. Modest ridging over the area brings quiet and sunny conditions on Sunday.
Temperatures will be slightly cooler on Sunday with upper 80s and lower 90s for highs.
317 AM CDT Sat Aug 28 2021 Thunderstorms will again be possible across the western and central Panhandles this afternoon and this evening and a couple may spread into the northeast CWA later on tonight closer to the upper level dynamics from a passing short wave trough moving across the northern plains. On Sunday a cold front should be across the northwest CWA and this will likely become a focus for additional showers and thunderstorms.
(Today through Sunday afternoon) An upper level trough is over the northern Rocky Mountains, and an upper ridge is over the east coast. The upper trough to the north has weakened the upper ridge over West Texas and Southeast New Mexico. 850 mb temperatures will be a little cooler over the area today resulting in slightly cooler high temperatures. The previously mentioned upper trough will move eastward with the flow becoming zonal by Sunday evening.
Mid level ridging expanding in from the Carolinas/Appalachians will allow the area to become firmly entrenched in the warm sector tonight into Saturday.
The combination of higher heights moving in ahead of the ridge and decreased insolation through the evening should result in a steady decrease of shower chances. Temperatures will be noticeably cooler overnight as well with those mountain valleys dropping into the lower 40s and colder pockets getting down into the upper 30s. The Palouse also is forecast to drop down into the lower 40s. Warmer temperatures aloft will cap cumulus clouds with dry weather expected. Winds look to get a bit breezy through the Cascade gaps late Sunday afternoon with the next trough of low pressure approaching off of the eastern Pacific.