Aikyam-Lab/Synoptic-Bench huggingface dataset:
Water vapor imagery and upper air analysis shows troffing/cyclonic flow over the northern Rockies with a strong upstream ridge over the north Pacific and ridging over the eastern CONUS. Forecast soundings suggest convective temps in the lower to mid 70s which should be achievable, and afternoon CAPES on the order of a few hundred j/kg. Wet bulb zero heights remain relatively low at around 10kft msl, so could see some small hail with any stronger cells, and mixed pcpn can be expected over the higher peaks. Activity will end from west to east tonight as PV exits and flat ridge builds in from the west. This ridge will bring dry/warmer conditions with increased downslope winds on Saturday and RHs back down to the teens. After high temps only in the lower to mid 70s today, we will see 80s on Saturday.
Showers and thunderstorms started to affect the Lower Keys around 130 am. Temperatures were able to drop to the low 80s at Key West and to the middle 70s at Marathon with the assistance of the rain.
Upper level ridging will remain in place across the region through the short term period, shifting just a bit eastward through Friday night. Lows tonight will drop into the lower to mid 70s. Dewpoints this afternoon are still in the lower to mid 70s in may areas, so lows will be close to those tonight. Isolated showers and storms are possible again tomorrow, mainly across west central KY and southern IN as the ridge starts to shift east.
648 AM EDT FRI AUG 26 2016 A cold front, will move east of the region today, allowing high pressure, to build in from the upper Midwest.
652 AM EDT FRI AUG 26 2016 Upper level high pressure in place with hot and humid weather through the weekend. Quiet weather on tap, with upper level high centered over the Central Appalachians. but with the upper high right over us opted to keep POPs below 15. Remaining on the humid side, with dewpoints struggling to drop below 70 across the lowlands. The area remains under an upper level ridge through the weekend.
A mid/upper level high pressure system is progged to remain quasi-stationary across the SE U. with a mid level trough developing across east and southern texas and an upper level weak low at 250mb developing to the south of the CWA.
Radar imagery does show the weak cold front stretching southwest to northeast across much of central Montana and which is about to move through Great Falls. A cold front has moved through north-central Montana and will continue advancing southward through Friday morning. Water vapor pix show a broad trof moving east of the zones with northwest flow aloft across Alberta and Central Montana. Also, most of the higher elevations along the eastern zones will be underneath the trof during the afternoon and a thunderstorm or two cannot be ruled out there, as well. Winds aloft will strengthen Saturday ahead of an approaching low pressure trof to the west.
631 AM EDT FRI AUG 26 2016 A cold front will move through northern New England this morning. High pressure builds in out of Canada on Saturday with another warm day in the 80s.
540 AM EDT FRI AUG 26 2016 A large ridge of high pressure at the surface and aloft will build over the Mid Atlantic Region through the upcoming weekend, bringing a string of warm and dry days.
141 AM EDT Fri Aug 26 2016 High pressure remains off the coast through tonight. A cold front will cross the region early Friday. High pressure will return for the weekend. A light southerly flow will allow for noticeably warmer and more humid conditions overnight compared to recent nights. A cluster of showers and thunderstorms have developed ahead of a cold front over Pennsylvania this evening. Current feeling is that the activity will weaken as it approaches our area due to the fact that it will be outrunning the cold front that will not get here until after sunrise. Not only is the timing out of synch with favored diurnal trends, but west/northwest winds will promote subsidence, and at all levels above the surface ridging will reinforce that subsidence. Ridging will keep muggy but rain-free conditions in place Friday night through Saturday night.
will start off with subsidence in lee of the trough passage, but should give way quickly way to another round of storm development, though under weaker support. The longwave pattern changes little over the weekend with a trough over the western and central states and high pressure over the SE U. The northern half of the forecast area will remain drier and under the col between the westerly flow over the northern tier states and the trough over the Great Basin and the southwest.
433 AM EDT FRI AUG 26 2016 A large ridge of high pressure at the surface and aloft will build over the Mid Atlantic Region through the upcoming weekend, bringing a string of warm and dry days.
The pattern aloft featured southwest flow across the Central Plains ahead of an upper trough translating into the Rocky Mountain region. At the surface, high pressure was oriented from southern South Dakota across Nebraska with the surface boundary located to our south across far southern Kansas into Oklahoma.
That said, a weak cold front will be in the area today before washing out, offering some source of lift.
The models are in good agreement this morning with the general trough pattern. The exact position of the trough axis waffles a bit north-south from model to model and run to run of the models. The current low pressure trough hanging over the west will very slowly move south. As low pressure at the base of the trough centers over southern California, the moisture feed will continue through southern Nevada, affecting areas south of highway 50 within the LKN CWFA.
Instability has also been on the increase with diurnal heating this afternoon, with the highest values found across central Missouri, south of where the morning MCV tracked through. With the boundary lingering in the KC metro area, the lowered FF guidance, the high PWATs, and the inherently prone issues the metro faces in a heavy rain event, felt it prudent to issue a FF watch for the metro and counties south and east. Despite the aforementioned boundary still forecast to wash out tomorrow, the forecast area will linger on the periphery of an upper ridge centered near the Mid-Atlantic states. The upper pattern will begin to flatten as the Northern Plains trough exits the area late into the weekend. By the mid week, a deepening trough over the Pacific Northwest will build a broad upper ridge across the central CONUS.
457 AM EDT FRI AUG 26 2016 A cold front will cross the region this afternoon.
137 AM EDT FRI AUG 26 2016 Upper level high pressure in place with hot and humid weather through the weekend. Quiet weather on tap, with upper level high centered over the Central Appalachians. but with the upper high right over us opted to keep POPs below 15. Remaining on the humid side, with dewpoints struggling to drop below 70 across the lowlands. with upper ridging across the eastern U. with best chances across the higher terrain counties. Stubborn high pressure continues though begins to erode as a tropical system slides westward towards the US mainland, however, quite a bit of model uncertainty so track of system is not well defined. Maintained schc to chance PoPs for the dirty ridge as it flattens.
Longwave trough across the Rockies developing east towards the Great Plains region. Overall today will see increasing chances for light showers south and west 12-18Z this morning as the long wave trough approaches our region. Upper level trough will be over the central Dakotas by 12Z Saturday, then moves off to our east Saturday afternoon.
The high res models point toward storms expanding in coverage from SW to NE this afternoon, which seems reasonable based on the projected frontal progression. Upper trough currently digging over Montana/Idaho to eject eastward this weekend.
356 AM EDT Fri Aug 26 2016 High pressure remains off the coast through tonight. A weak cold front will cross the region this morning. High pressure will return for the weekend. A LARGE RIDGE OF UPPER-LEVEL HIGH PRESSURE IS CENTERED OVER THE SOUTHERN APPALACHIANS. OVER THE COURSE OF TODAY AND TONIGHT THE RIDGE WILL SLOWLY SLIDE EAST-NORTHEAST AND END UP CENTERED DIRECTLY OVER VIRGINIA BY LATE TONIGHT. A COLD FRONT IS STRETCHED FROM NEAR ST. AND IN FACT THE NORTHWEST FLOW DEVELOPING TODAY WILL LIKELY SUPPRESS CONVECTION DESPITE THE HIGHER HUMIDITY NOW IN PLACE. WARM AIR SURGING NORTH AHEAD OF THE FRONT COMBINED WITH THE HIGH HUMIDITY WILL ALLOW TEMPS TO SURGE TO THE MID-UPPER 90S WITH HEAT INDICES IN THE LOW 100S. DRIER AIR WILL GRADAULLY SLIDE SOUTHWARD FROM THE NORTH AS HIGH PRESSURE BUILDS IN.
139 AM EDT FRI AUG 26 2016 Aviation A weak cold front moving across Lower Michigan will result in scattered storms south of a Lansing to Kalamazoo line late this afternoon. Latest mesoanalysis shows instability slowly building across the southeast cwa ahead of a cold front that extends from near Saginaw Bay southwest to St Joe. High pressure will build into the state behind the front and Friday/Friday night will be dry. After that low pressure moving northeast toward the western Great Lakes will enhance south flow over the cwa Saturday and chances for storms will increase Saturday afternoon and night.
With the warmer air will also come drier air at the low levels which will help to reduce the overall heavy rain potential as well as increase the wind gust potential.
Water vapor imagery continues to indicated a mid to upper level ridge centered over the southern Appalachian Mountains and weak 500mb low over the western Gulf of Mexico.
the upper trough axis over the western CONUS continues to slowly advance eastward with 595 DAM ridge spinning over the southern Appalachian Mountains per water vapor imagery.
234 AM EDT FRI AUG 26 2016 A large ridge of high pressure at the surface and aloft will build over the Mid Atlantic Region through the upcoming weekend, bringing a string of warm and dry days.
301 AM EDT FRI AUG 26 2016 High pressure will push east across the great lakes today through saturday.
High pressure will move across WI today although scattered to broken cirrus will occur due to swly flow aloft and the upstream convection. The high clouds will probably keep temps down a degree or two along with an afternoon lake breeze as well. A wave of low pressure will follow into IA with a sly 30 kt LLJ moving into srn WI. Though confidence is on the higher end that there will be showers/storms on Saturday, not nearly as confident in the timing at this point.
358 AM EDT FRI AUG 26 2016 A cold front, will move east of the region today, allowing high pressure, to build in from the upper Midwest.
With the generally easterly flow and increased rain chances, slightly cooler temperatures should occur across the eastern zones with highs lingering in the lower 90s.
Overall will see increasing chances for showers south and west 12-18Z Friday morning as a long wave trough starts to move into the region. A upper level trough from Montana through Nevada this afternoon is forecast to propagate into the Northern Plains on Friday.
Offshore flow this morning transitions to gusty up-valley flow this afternoon as the thermal trough moves over the east side, as the pressure gradient west to east tightens mid afternoon.
331 AM EDT FRI AUG 26 2016 A cold front will move through northern New England this morning. High pressure builds in out of Canada on Saturday with another warm day in the 80s.
However, an upper ridge building back over the weekend will keep temperatures above normal. Expect lows tonight ranging from the mid to upper 60s northwest to the lower 70s in the south. On Friday, high pressure will be trying to build in. Highs on Friday will be slightly cooler, ranging from the mid 80s in the north to around 90 along the Ohio River. Friday night into Saturday the H5 ridge will build back to the north into the region. Large area of high pressure over the southeastern U.
319 AM CDT FRI AUG 26 2016 Area of convection continues to shift north in recent hours with nearby radar wind profiles showing veering trends in the lower levels. RAP analysis indicates several weak waves upstream in moderate southwest flow aloft with a larger scale trough working east across the central and northern Rockies. Convection may be ongoing Saturday morning as the southern end of the Northern Plains trough moves through the Central Plains. The warm front should lift north of the area with southerly winds developing through the morning hours.
219 AM EDT FRI AUG 26 2016 Upper level high pressure in place with hot and humid weather through the weekend. Quiet weather on tap, with upper level high centered over the Central Appalachians. but with the upper high right over us opted to keep POPs below 15. Remaining on the humid side, with dewpoints struggling to drop below 70 across the lowlands. The area remains under an upper level ridge through the weekend.
At the surface, high pressure is centered over southeastern South Dakota, sliding slowly to the east. On Saturday, another weak disturbance is forecast to move across the High Plains.
A few stray isolated thunderstorms may develop over the high terrain immediately along the Continental Divide, but with little consequence.
Hot and humid conditions will persist into the weekend as upper- level ridging centered over the Virginias and Carolinas remains in control. The low-level jet over the Mississippi Valley has struggled to produce any nocturnal convection, and today's precip forecast will hinge on how far westward the influence of ridging can win out. Precipitable water values will remain well above climo, but with the moisture concentrated in the boundary layer, and convective temps in the lower 90s, believe afternoon convection will remain isolated at best. Tonight into Saturday we'll be closer to the periphery of the upper ridge, so we could see nocturnal convection creep into west-central Kentucky and southern Indiana around daybreak Saturday.
Can't rule out thunderstorm chances on a daily basis given the high moisture content and weak disturbances pushing through the area.
330 AM EDT FRI AUG 26 2016 Mid/upper level ridging across the eastern CONUS will keep a hot and humid air mass in place across eastern Kentucky through the weekend. Can not rule out an isolated shower or thunderstorm Saturday afternoon across our southern and southwestern zones as a very weak upper level disturbance manages to track around the south side of the mid/upper level ridge centered over the Atlantic seaboard. Seasonably hot afternoon temperatures will climb into the lower 90s today and Saturday.
355 AM EDT FRI AUG 26 2016 A cold front will move through northern New England this morning. High pressure builds in out of Canada on Saturday with another warm day in the 80s.
Upper level high pressure continues over Tennessee. A short wave on the west side of this high continues to bring showers and isolated thunderstorms to Arkansas, mainly central and south. Rest of the night should be dry, but another short wave rotates around the high Friday for more showers and thunderstorms.
A low pressure system entering southeastern California and passing through Arizona will interact with this deeper moisture. A better vertical wind shear profile associated with the low will aid in organizing and sustaining thunderstorms, some of which could produce very heavy rainfall and strong winds.
401 AM CDT Fri Aug 26 2016 Southeast Texas lies on the western periphery of an upper level ridge centered over the central Appalachians.
A deep layer ridge of high pressure will remain centered over the Mid-Atlantic through tonight. Strong subsidence under this ridge will suppress thunderstorm development across much of the area. Highs will remain hot with temps in the low to mid 90s inland to around 90 near the coast. Lows tonight will fall in the low 70s inland to upper 70s along the coast.
451 AM EDT FRI AUG 26 2016 A cold front will move through northern New England this morning. High pressure builds in out of Canada on Saturday with another warm day in the 80s.
130 PM EDT SAT SEP 3 2016 High pressure will continue to build out of the northern Great Lakes and into northern New England today. The high will shift offshore late tonight and remain anchored over the maritimes through mid week.
309 PM EDT SAT SEP 3 2016 A large area of high pressure, centered over Ontario, will keep our weather mainly dry, through the rest of the holiday weekend.
102 PM EDT SAT SEP 3 2016 Strong high pressure over the Great Lakes region will gradually pull eastward into southeast Canada through Labor Day.
205 PM MDT SAT SEP 3 2016 Deep pac nw upper trough will remain in place in the period, supporting sw flow aloft. Convection will trend east and wane overnight with much cooler conds settling into the western 2/3, with 40s and 50s expected for lows there. Showers will linger over the far nw overnight given prox to the upper trough. Upper trof will be across the northern Rockies early in the week, then slowly move east across the northern plains through the remainder of the week.
541 PM CDT SAT SEP 3 2016 206 PM CDT Quiet weather continuing today and through the period as high pressure remains in place. Another cool night expected with lows once again falling to the 50s for most locations, with slightly warmer temps around 80 on Sunday.
Early this morning a broad mid-level ridge was stretched across the eastern CONUS with a mid-level trough tracking across the northwestern U. With the expected increasing low and mid-level cloud cover today, have continued to trend a bit cooler with temperatures with highs in the upper 70s to around 80 degrees. Overnight low temperatures will range from the low to mid 60s from east to west with the increasing cloud cover helping to keep temperatures a few degrees warmer across central KS. but keeping the bulk of any passing short wave trough energy to the north at least through mid week.
High pressure is firmly established over lower Michigan, southern Ontario, and into southern Quebec this morning. This in combination with the upper level ridge also centered over the Great Lakes will continue to produce clear sky over SE Michigan today through Sunday.
/issued 356 PM CDT SAT SEP 3 2016/ Upper ridge overhead has produced strong subsidence with mostly clear skies today and only limited CU across parts of the region. The other noticeable change will be temperatures warming back into the lower 90s as the upper ridge continues to dominate through the Labor Day weekend.
1246 PM CDT SAT SEP 3 2016 228 AM CDT High pressure is settling over the region and will dictate our weather through Labor Day. The upper level low associated with Hermine will stall just off of the mid east coast tonight.
Models show this vorticity maximum moving into the lower and middle Texas coast this afternoon.
250 PM EDT SAT SEP 3 2016 Strong high pressure over the Great Lakes region will gradually pull eastward into southeast Canada through Labor Day.
A low pressure system moving into the western states will bring dry southwesterly flow into Arizona, with storm chances confined to far northern Arizona through this evening.
Models continue to show elongated high pressure extend from the mid CONUS down into south Texas. an inverted trough will approach from the Bay of Campeche overnight. It appears that the upper level ridge will help direct the the upper level wave north and west. there will be at least some moistening of the atmospheric column as deep layer moisture increases as the trough moves through the Deep South Texas and the RGV.
As mean flow shifts to the SW WAA should increase and model consensus is for slightly warmer temperatures.
The large western trough of low pressure aloft is in solid control most of the western and north central states, streaming in Pacific moisture from the California coastline through the Great Basin and northeastward through eastern Montana. Mostly cloudy skies from earlier today are partially clearing, but are expected to become mostly cloudy to overcast by tonight from the south as the trough digs further into our region. Sunday: The upper low center intrudes further into the northern Rockies and pushes the rain shield across the entirety of the CWA.
646 PM EDT SAT SEP 3 2016 A large area of high pressure, covering the Great Lakes and much of the Northeastern U.
High Pressure bringing pleasant early Fall weather to OH Valley. High Pressure over the Sleeping Bear Dunes National Lakeshore MI/Traverse City area continuing to usher in mid to upper 50 dew points. By Sunday, Hermine becomes post-tropical and stalls off the mid- Atlantic coast while high pressure holds to the north across the Great Lakes. While and upper ridge over MS/AL begins to start nudging north, but it will take some time for humidity levels to increase significantly and lows will be 2-4 degrees warmer in the low to mid 60s.
KOTX sounding shows a cold pool of near -21 deg C air at 500mb remains nested inside the trof overhead of Eastern Washington and Northern Idaho and thus the resulting conditionally unstable airmass will remain conducive to allow afternoon and early evening convection given the proper trigger. therefore pops remain fairly low and confined to the higher mountain terrain of the forecast area for this afternoon and evening with other locations having perhaps some various form of afternoon and early evening cumulus.
253 PM CDT SAT SEP 3 2016 19Z water vapor imagery and profilers show southwest flow aloft with the upper trough axis from northern CA into the northern Rockies. At the surface a ridge of high pressure remained just to the east of the forecast area as a trough of low pressure in the lee of the Rockies gradually deepened. Lows tonight are expected to be in the lower 60s with a little more mixing and cloud cover anticipated overnight. A strengthening pressure gradient and southerly winds of 10 to 20 MPH are expected to bring warmer air in to the forecast area Sunday. Highs are therefore anticipated to be warmer with readings into the lower and middle 80s.
Surface analysis this morning places a 1027 mb ridge of high pressure centered over the Great Lakes Region and Ontario/Quebec. Meanwhile, Post-Tropical Cyclone Hermine was located along the North Carolina/Virginia coast. The ridge of high pressure extends into the Lower Mississippi Valley this morning resulting in sunny skies and temperatures as of 10 am CDT in the 70s at most locations. Temperatures are forecast to be about 2 degrees warmer across the board, with afternoon highs in the mid/upper 80s. This should keep overnight lows slightly warmer, with most areas remaining in the mid/upper 60s.
102 PM EDT SAT SEP 3 2016 High pressure centered over Southern Ontario will gradually shift eastward through the weekend.
300 PM CDT SAT SEP 3 2016 Latest water vapor satellite imagery shows upper level ridge over the Great Lakes region and upper level trough over the Canadian Rockies/Pacific Northwest. Surface/upper level ridge over the Great Lakes region remains in control of the forecast area. Temperatures should be slightly warmer Sunday. 12z GFS/NAM suggest warmer air to advect into the forecast area.
Pattern dominated by large upper level ridge over the central and eastern CONUS with Hermine dominating the northeast states and offshore as she becomes extratropical and broadens/deepens. With extratropical Hermine trapped under the larger upper level ridge.
224 PM CDT SAT SEP 3 2016 206 PM CDT Quiet weather continuing today and through the period as high pressure remains in place. Another cool night expected with lows once again falling to the 50s for most locations, with slightly warmer temps around 80 on Sunday.
Scattered showers and storms have been able to develop along a weak boundary trailing Post-Tropical Cyclone Hermine.
316 PM CDT SAT SEP 3 2016 Ridge axis extends from near Chicago southwest to near Springfield Missouri. Light wind in the vicinity of the ridge axis and low dew point temps should allow for good radiational cooling. which may not be enough if lows end up being warmer than expected.