Aikyam-Lab/Synoptic-Bench huggingface dataset:
Associated cold front will be through the forecast area by 12Z. windy and cooler. WRF Bufkit soundings showed the highest winds will be generally E of KBIL. Thus confined PoPs to the high elevations. Weak upper ridging builds into the area Sun. Sunday will be a little warmer than today with continued low humidities.
High pressure moves in Sunday night with lows likely dipping into the 50s for many locations which is something we have not seen for several days now.
This moisture increase will evolve as the upper high becomes more consolidated over north-central NM and the four corners region in the next day or so. The pattern then shifts with the upper high amplifying and becoming centered over southern Nevada. Thus, helping steer thunderstorms developing in the higher terrain of the Rim and White Mountains southwest in the lower deserts.
401 AM CDT SAT JUL 23 2016 Upper level high pressure continues to weaken today; however, lee side troughing means southwest flow at the surface will translate into another day with triple digit heat for most. Sunday will see temps in the upper 90s as lee side troughing remains in place. However, a frontal boundary stemming from a low pressure system in eastern-central Canada will bring more widespread showers and thunderstorms to the area.
Strong high pressure will bring a significant warming trend this weekend with temperatures approaching the triple digits across the interior.
Strong upper level ridging sprawled across the Southern Plains and Rockies (in the 598 decameter height range at 500 mb) was sending a northerly flow over the region. But it could be removed later tonight if new guidance suggests cooler conditions to end the week. A light northerly flow aloft, moving around upper level ridging west of the region will continue into late Saturday. Shower activity should dissipate Sat evening as cooler and more stable conditions are realized.
The 00Z upper air analysis indicated the center of the mid-level ridge had started to retrograde slightly with heights about 20 m lower than 24 hours ago over the central and southern Plains.
The upper ridge begins to retrograde a bit on Sunday, which should allow for a greater concentration of afternoon thunderstorms along/south of I-44. Temperatures will be ever so slightly cooler across this area, with readings in the low to mid 90s.
329 AM CDT SAT JUL 23 2016 Both the high resolution short range and coarser medium range guidance suggesting the greatest eastward expansion of the ridge axis and accompanying subsidence and capping lid for widespread convection spreading across most of the WFO PAH forecast area through Sunday.
High pressure will keep hot temperatures in the forecast for the region through the weekend.
331 AM CDT SAT JUL 23 2016 Over the next few hours, will be watching areas of showers and storms currently moving east-northeastward across portions of north central KS and south central NE along the nose of the low-level jet.
Afternoon temperatures expected to top 90 degrees across much of the lowlands today. Combined with dewpoints in the low 70s, heat indices will climb above 100 degrees.
Temperatures will be 5-10 degrees below normal today in the wake of yesterday's cold front. As our upper level flow changes from west today to northwest tonight and then to southwest Sunday, warmer air will start to move back into the region.
The latest water vapor imagery shows the upper level low circulating over southeast Alberta with an associated cold front now into eastern Montana. Still expect periodic showers and thunderstorms ahead of the cold front. With the cold front not pushing through until 21z-00z, the greatest cape axis and shear will reside here for possible severe thunderstorms.
The upper level ridge across the Southern Plains will weaken slightly today, but temperatures will remain hot.
The upper ridge has started to shift off to the west, but our region will remain under its influence.
Temperatures were in the lower 80s with winds generally from the east-southeast near 10 knots.
AMS begins to warm today in wake of short wave trough pushing through the PacNW and upper high to the south expanding northward.
This is borderline for Heat Advisory criteria, but with the convection and associated cloud cover coming in, there is potential to end up a bit cooler than forecast. Once this initial round of convection moves through, another larger complex of storms is expected to initiate across western MN as a potent short wave tracks along the international border toward Winnipeg by tonight, and drags a cold front into the Gopher State. Any lingering rain will exit the area Sunday morning as the short wave trough continues east through Ontario.
Upper trof across the northern U. but with the upper level flow increasing as the ridge flattens today. Thunderstorm outflow will will likely aide in driving a more concerted push of cooler and more moist air into SE Colorado tonight.
A cold front will move east from the central and northern plains tonight, possibly causing thunderstorms to move into northwest portions of our area by daybreak Sunday.
upper low continues to move east into northern Idaho this evening. Temperatures will be much cooler than last night with lows in the 40s and 50s. Flow becomes westerly Sunday for continued mostly sunny conditions and warmer temps.
Expect another round of isolated to scattered convection on Saturday afternoon as the upper level ridge of high pressure becomes less influential on our weather. /issued 954 PM CDT FRI JUL 22 2016/ For the 10 PM update have removed the rain chances for much of the overnight hours except for late tonight when have added a slight for the East and Southeast sections around the Southern periphery of the mid-upper level ridge of high pressure and with the approach of disturbances in the 7H and 5H level around the periphery of the ridge aloft.
At 300 mb, a sprawling ridge of high pressure had shifted west and was now centered over N NM. A weak upper low was spinning over W TN/N MS. Have leaned toward the drier GFS as the upper ridge still looks close enough to the region to impart some subsidence.
Current temperature forecast for Saturday is for maximums in the lower 90s, and this will combine with humidity to once again push heat indices to around 100. Broad, flattened mid and upper level ridge across the southern CONUS buckles in response to multiple short wave troughs tracking across the northern tier. The main center of the high retrogrades to the west coast just as the all too familiar Bermuda High reforms off the southeastern United States. In between a mean trough develops over the Upper Mid-West and Great Lake Region by the end of the forecast window.
Little significant change in the weather is on the immediate horizon, and fair skies with an occasional smattering of low clouds along with light to moderate southeast winds and warmer than normal temperatures will dominate conditions through the short term.
Have backed off on the high temps for today from what we had forecast yesterday for today but heat indicies will still be above 100 west of plateau with a few above 105 back along the Tennessee River this afternoon. On Sunday look for scattered convection once again developing with temps up in the low 90's west of the plateau.
Upper level high pressure will continue to dominate the pattern. Forecast thickness values will be a touch higher today suggesting a degree or two warmer compared to Fridays temperatures. However the center of the upper level ridge will shift westward after this weekend.
The weekend looks to continue with mainly sunny skies and warmer than average temperatures. Additional amplification of the upper trof on Saturday looks to be wasted by the significantly drier air and high pressure at the surface. High pressure continues to dominate through most of Sunday under mainly sunny skies with highs in the 80s to around 90.
The highest probabilities of severe this evening are probably over NW/NC SD where instability remains high and deep layer shear is highest. The rest of the short range looks fairly tranquil as high pressure builds south over the area. With the mid level ridge building out west, the flow will turn to northwest across much of the Northern Plains.
VFR conditions will prevail beneath high pressure aloft.
Second favored area will be along the deeper moisture gradient which looks to set up along the higher terrain just north of Interstate 70. The upper level ridging over the region will be suppressed as we start off the new week with the deeper plume dropping south.
Convective activity in the wake of the cold front has moved to eastern Montana. Radar returns over northwest Montana are associated with the upper trof axis as it continues to approach from the west. Gusty west-northwest winds will gradually weaken tonight as high pressure builds over the area. W to E moving cold front ahead of the trough has entered NW MT and will sweep east across the forecast area late this afternoon through early this evening. Primary threat from storms today will be strong winds due to a dry low-level airmass, particularly over SW MT with increasing winds aloft also contributing to the high wind threat.
Warmer temperatures are expected for inland areas over the weekend, while continuing onshore flow will maintain seasonably cool conditions near the coast.
A large ridge over much of the nation will keep a hot and humid airmass in place across central Indiana through the weekend.
Convection is expected again this afternoon with the higher chances closer to the coast. Surface ridging will be in control of the local area through Saturday. Drier air will continue to move into the forecast area from the northeast along the periphery of the stacked ridge centered over the Plains. With ridging in place, expect below normal coverage of showers thunderstorms on Saturday afternoon, in the 20-30 percent range. By Sunday, model guidance is in agreement with bringing a weak area of upper level low pressure inland from the NE Florida coast. High temperatures both days will be in the mid 90s with lows in the low to mid 70s.
342 AM CDT SAT JUL 23 2016 Initially this morning, a few isolated showers may be found as far east as the highway 283 corridor around 12z before dissipation. By tonight, the week cold frontal boundary is modeled by the NAM/WRF to move into northern-west central KS, providing a convergence zone for thunderstorms to develop by early evening, with locally heavy rain, lightning and strong gusty winds.
615 PM MDT FRI AUG 26 2016 Water vapor satellite imagery showing an upper level trough dropping into the Great Basin with convection firing out ahead of it over the Wasatch and Uintas in Utah and the higher terrain over western Colorado. Expecting cooler temperatures tonight, similar to yesterday, due to the rain cooled air with some light snow again at the higher peaks mainly above 12kft. On Saturday, the upper level trough will split with a cutoff closed low forming over southern California into Arizona, with our CWA in the deformation zone between the split trough. This will result in another active day on Saturday with storms more numerous over the higher terrain from the Bookcliffs southward with some valleys being impacted later in the day.
Another impulse will bring a chance of convection, best chances NW of the Ohio Saturday, diminishing chances into the afternoon and evening as the surface warm front, which never really makes it in here, heads NE away from the CWFA.
750 PM EDT FRI AUG 26 2016 High pressure build in tonight and remains in place for the weekend.
613 PM CDT FRI AUG 26 2016 The synoptic pattern early this afternoon features a broad subtropical ridge across the southeastern CONUS with a trough digging into the northwestern CONUS. Main threat will be locally strong winds, but the backbuilding nature of some of the convection in the high PWAT airmass (around 2 inches) will also lead to some localized flash flooding concerns as well.
943 PM EDT FRI AUG 26 2016 Cooler and drier air will filter in tonight behind a cold front. High pressure builds in out of Canada on Saturday with another warm day in the 70s and 80s.
Saturday will see gradual clear from southwest to northeast as the upper level low moves through northeast SD. Will maintain the low threat for showers and isolated thunderstorms along highway 14 as this low passes. On Saturday night the upper low to the north continues to shift off to the east. Have raised forecast lows into the low and mid 60s with low level moisture hanging around the area.
Main upper level trough to push east region which could allow for a few isolated storms still in the east/south through the day.
837 PM EDT Fri Aug 26 2016 A dry cold front will move through the area this evening.
High pressure aloft over the region will weaken, allowing the tail end of a low pressure system over western Canada to move across the area on Saturday. This combined with moderately strong onshore flow will result in significantly cooler temperatures on Saturday.
602 PM CDT FRI AUG 26 2016 Manual 12z upper-air analysis showed a long-wave trough from the lee of the Canadian Rockies into the southern Rockies with a downstream sub-tropical high centered over the southern Appalachians. At the surface, 18z mesoanalysis placed a low over northeast Kansas -- coincident with the upper-air system-- with an associated warm frontal segment extending northeast through northwest Missouri into south-central Iowa. Showers and thunderstorms now developing over northeast Kansas in association with the above-mentioned impulse are expected to spread northeast along the warm front with portions of southeast Nebraska and southwest Iowa being impacted by this activity. Mid-level heights will rebound on Saturday into Saturday night with the passage of the polar-branch trough (mentioned above) to our northeast.
729 PM EDT FRI AUG 26 2016 An upper level ridge will extend across the region through the weekend. Tonight, low level moisture and instability axis extends roughly sw- ne in vicinity of the highway 1 corridor. With the core of the mid/upper level anti-cyclone covering the northern piedmont and foothills, subsidence over our northern counties will likely inhibit any convective development. Otherwise, expect clear-partly cloudy skies with overnight temperatures in the low-mid 70s. Core of mid/upper level ridge drifts northward into central Appalachians/northern Mid-Atlantic during this period. Otherwise expect partly cloudy skies with overnight temps in the low- mid 70s.
All convective activity over the area should dissipate around sunset to allow for a mild evening in the low to mid 70s with increasing cloud cover overnight.
During the forecast period, the mid-level ridge currently across the Mid-Atlantic states will shift to the west and is expected to be centered over the Southern Plains by mid-week.
814 PM 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.
Tonight Through Saturday An upper level low pressure trough passing through western and most numerous over the higher terrain. but drying will be the trend through the late night and morning hours as dry and warmer air moves in.
These developments resulted in cooler daytime temperatures today across Santa Cruz County, across much of the North Bay, as well as portions of the East Bay and southern Santa Clara Valley. Ben Lomond had a high of only 67 (14 degrees cooler than yesterday's 81). But for the most part, temperatures will remain at least slightly cooler than normal through the weekend.
1132 PM 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 moisture that is currently in place across the region will begin to be shunted to the south and southwest tonight and Saturday as an upper level low spins along the Texas Coast.
Warmer air will push into the area as well, with highs in the lower to mid 80s.
A north to south band of convection extended over the northern and central plains ahead of a short wave trough. The NAM is also more aggressive with an 850 warm front and low and lifting the heavy rain into north central Wisconsin Saturday afternoon.
1024 PM EDT FRI AUG 26 2016 High pressure builds in tonight and remains in place for the weekend.
608 PM MDT FRI AUG 26 2016 17Z Water Vapor Imagery and RAP analysis indicated two short wave troughs approaching the area. The latter trough will likely be the primary trigger for precipitation chances this afternoon and evening. Last few scans of visible satellite show an increase in cumulus ahead of short wave trough and its sfc reflection. Relatively high mixing ratios and CAPE in the 1000 to 1500 J/Kg range along and southeast of this boundary will allow thunderstorm development mainly during the afternoon and will focus in the eastern and southeastern portions of the CWA where instability is the highest.
Proton Synoptic Setup: Short term begins with the base of a trough moving through northeast Montana and running into Saskatchewan and northern Manitoba. The High pressure heat dome is beginning to reform over Nevada with the ridge running up into Washington and British Columbia. This afternoon and evening: trough will continue to mosey through the area and bring a few scattered rain showers and isolated thunderstorms until roughly sunset when activity should taper off very fast.
TEMPERATURES ARE RUNNING A 10 TO 15 DEGREES COOLER THAN YESTERDAY.
The recent warming trend will continue into tomorrow, with highs about 5 degrees warmer than today.
1225 AM EDT SAT AUG 27 2016 High pressure will build into the region tonight.
Thus, we have expanded the low thunder mention across most of the southern Texas Panhandle and northern South Plains after midnight. /issued 316 PM CDT FRI AUG 26 2016/ Upper trough axis from 300-250 mb extended from the eastern TX Panhandle southwest to the Davis Mountains. Mid-level moisture has remained more resilient ahead of this trough, mainly over the eastern Permian Basin where numerous diurnal storms are noted. Farther west, subsidence behind the trough should keep convection suppressed to mostly stable Cu, but have inserted a broad mention of isolated storms through tonight as water vapor reveals additional lift and re- moistening upstream within additional cyclonic flow. Unlike recent days, less interference from low to mid clouds should allow for warmer max temps especially on the Caprock.
A surface boundary associated with this trough stretches from roughly Rock Springs WY back to near Nephi and Ibapah.
Drier and warmer still look on track for Saturday with winds increasing by afternoon.
General troughiness over the north(west)ern Gulf, with a higher plus 2 inch PWAT air mass advecting in on mid-level easterlies, will be enough to (re)generate offshore convection that will move onshore through the early Saturday morning hours. Upper ridging has now retreated back over the mid-Atlantic states with relatively lower regional heights/pressures providing enough instability (within this near-saturated column) to maintain moderate to high chance Saturday daytime POPs for clustered thunderstorms. Model solutions target the southern CWA for the highest weekend QPF, or over counties that are already at (or over) 60% soil saturation.
The main upper trough will begin to move into the western Dakotas by the early morning hours, and another round of showers quickly sets up from southwest to northeast across our CWA. Tomorrow, the upper trough moves across the region as it lifts into MN.
721 PM EDT FRI AUG 26 2016 High pressure will build into the region tonight.
920 PM EDT FRI AUG 26 2016 An upper level ridge will extend across the region through the weekend. Dry sinking airmass associated with the strong ridging aloft will result in clear skies overnight with winds remaining light and variable. Morning lows in the low-mid 70s. Core of mid/upper level ridge drifts northward into central Appalachians/northern Mid-Atlantic during this period. Otherwise expect partly cloudy skies with overnight temps in the low- mid 70s.
951 PM EDT FRI AUG 26 2016 High pressure axis moves offshore overnight as a weak cold front slowly drops into the region through Saturday.
Chattanooga Airport, TN 74 94 72 90 / 20 20 10 40 Knoxville McGhee Tyson Airport, TN 73 94 71 90 / 10 20 10 40 Oak Ridge, TN 73 95 71 89 / 10 20 10 30 Tri Cities Airport, TN 67 93 68 90 / 10 20 20 20.
837 PM EDT FRI AUG 26 2016 Upper level high pressure in place with hot and humid weather through the weekend. Expect the lower atmosphere to decouple providing calm flow. Current thinking is that High Pressure. latest guidance is warmer than previous numbers and have bumped highs up a degree or so.
Trended warmer and drier which pushes afternoon RH values under 15 percent and raises some fire weather concerns.
Farther to the east an upper level ridge, over the southeast United States, is noted as it keeps pumping moisture north into the Plains from the western Gulf resulting in precipitable water values running around 1. expectations are that areas within the sector of the inverted trough will destabilize rapidly this afternoon as a warm front lifts into; which seems to be working out well so far as visible satellite shows the cloud field across that part of eastern Kansas becoming increasingly agitated while the radar shows scattered storms developing. In general, current short and mid-range models all point at the upper level ridge spinning over the deep south persisting through the weekend into the beginning of next work week.
707 PM EDT FRI AUG 26 2016 High pressure will bring pleasant weather to NY and PA tonight through Saturday.
754 PM EDT FRI AUG 26 2016 High pressure will be nudged eastward on Saturday as a warm front moves northward toward western Ohio Saturday evening.
1056 PM MDT FRI AUG 26 2016 Current surface analysis shows low pressure over eastern CO, with trough stretching northward across eastern WY into MT. Upper level analysis shows broad trough across the Rockies and high plains, with numerous disturbances within the trough across the region. Temps are mostly in the 60s, with 50s across the higher Black Hills. Unsettled weather will continue through much of tonight, then dry and warmer weather will return for the weekend as the upper trough shifts east of the region on Saturday.
Thunderstorms with cooler than normal daytime temperatures will continue through the weekend as a weak low pressure system moves into Arizona. A trough of low pressure is dropping south through the Great Basin this afternoon while deep monsoon moisture (1-2 inch Pwat) resides over Arizona. The low will provide enough lift for some storms to continue through the night tonight. Saturday is expected to be active again as the trough moves over the state.
Models maintain midlevel low/trough axis hugging along the upper/mid Texas coast tonight through Saturday night.
So far, shower lines have been well dispersed up and down the coast, but with the high moisture and breezy low level winds, will have to watch for local heavy rain if showers become repeating over the same area. An inverted trough (tropical wave) will move through the central/northern Bahamas through Saturday.
Upper trough across the region today has a short wave impulse streaking through the base which fired off some thunderstorms this morning over our south and east. Next round of convection will be generated by some energy dropping down from Alberta behind the trough axis. gradual ridging will lead to zonal flow over the region. This will create drier/warmer conditions with increased downslope winds and RHs back down to the teens.
Surface wise, a modest tropical wave extends from the southeast Bahamas southward into the island of Cuba, with a decaying ridge of high pressure well north of our region.
802 PM EDT FRI AUG 26 2016 Aviation Low pressure will move toward northern Lower Michigan Saturday.
During the night expect more convection to fire west of the area as more energy rides around an upper ridge and 850mb winds increase.