Aikyam-Lab/Synoptic-Bench huggingface dataset:
Large scale ridging slowly pulls farther west-northwest tonight and Saturday leaving lots of dry air in place across the region. 18Z KCRP sounding showed PWATs have modified just a tad but the low- level inversion, due to the massive subsidence and compressional warming, has strengthened to nearly 5C.
Frontal boundary across the southern FA will begin to lift north as a warm front during the day Saturday.
303 PM CDT FRI JUN 17 2016 Upper ridge currently centered over western KS, which where the thermal ridge resides. At the surface there is an expensive high pressure over the Great Lakes region. On the western periphery of that high is the remnants of a cold front that swept through the Midwest yesterday and overnight. Day time mixing has not lowered the dew points much due to the depth of the moisture in the lowest levels. One thing more certain is that the east to southeast flow in the low levels will lower the temperatures and dew points across the area. Also, any cloud cover or precipitation will cause cooler temperatures.
A weak warm front is slowly moving north across the Northern Rockies resulting in some shower production this afternoon. An approaching surface cold front will strengthen as it passes across the Northern Rockies Saturday, resulting in a tightening pressure gradient. Meanwhile, growing instability throughout the afternoon will work in tandem with the cold front to draw mountain top winds towards the surface. However showers and thunderstorms will become increasingly numerous during the afternoon and especially as the cold front passes with the strongest cells bringing a threat for brief heavy rain, lightning and especially gusty winds.
351 PM EDT FRI JUN 17 2016 The weather will be fair through the weekend with temperatures gradually warming to above normal as high pressure dominates. Ridging building in at the surface and aloft will aid in subsidence tonight. Upper ridging builds into the region from the west while an upper low spins around off the Carolinas.
As a result, the high temperatures should be a couple degrees warmer (topping out in the lower and mid-80s).
222 PM EDT FRI JUN 17 2016 In the wake of a cold frontal passage, abnormally dry and cool high pressure will build in over the weekend.
We still expect any leftover convection in the morning to lift north during the day as the warm front lifts north into northern Minnesota. Temperatures are expected to warm to 85-90 once again during the day with heat indices in the lower to middle 90s over southern Minnesota.
616 PM EDT FRI JUN 17 2016 High pressure will provide a fair weather pattern through the weekend.
127 PM EDT FRI JUN 17 2016 High pressure will continue to provide sunny skies through this afternoon. Warmer conditions are in store through this weekend with modest humidity levels.
134 PM MDT FRI JUN 17 2016 Latest upper air analysis indicates a ridge over the Central Plains with a trough over the Pacific Northwest. During the early afternoon an upper level short wave trough will move over the dry line and deepen, and the low level jet will develop with the nose of the jet over the east half of the area. As the afternoon progresses anticipate storm coverage to increase north of Highway 36 then spread southeast as the short wave trough over the dry line moves southeast around the retrograding ridge. Large hail is not anticipated to be much of a threat due to the low deep layer shear.
305 PM EDT FRI JUN 17 2016 Strong high pressure and dry air remain firmly in control of the weather across the Great Lakes region this afternoon. Otherwise, high pressure will remain built into Lower Michigan through the day and night.
200 PM MDT FRI JUN 17 2016 Upper level pattern continues to be dominated by large scale ridge across the central US. A cold front is moving into northeast Colorado and is just now moving into NW Yuma county. As cold front sags south and LLJ kicks in we should see an increase in thunderstorm coverage, with activity possibly lingering into the night. Regarding Severe Impacts: While this type pattern generally favors pulse type thunderstorms, the high CAPE profiles and higher ELs raises the possibility for taller updrafts and larger hail potential. Saturday: We will be post frontal with a slightly "cooler" air mass in place. Complicating things will be position of ridge center and how soon it moves into our CWA.
A Bit Cooler Today and Storms in the Vicinity. First, a boundary has worked south through the region, bringing slightly cooler temperatures to the east. As of 2 pm MDT, Lamar was 4 degrees cooler than yesterday at the same time, La Junta 3 degrees cooler, Springfield 2 cooler, Trinidad 1 cooler, Springs 1 cooler, Canon City was the same and Pueblo was actually a degree warmer. Across the mountains and high valleys, Alamosa was 1 cooler and Saguache was the same but most other places were warmer than yesterday by 1 to 5 degrees. No storms down here yet but according to some of the high resolution models, there could be a spotty storm or 2 down our way late this afternoon or evening.
332 PM CDT SAT MAY 28 2016 Short range (Today through Tomorrow): The upper level trough that has been our weather maker this week is evident on water vapor imagery centered near Sioux Falls. This trough is expected to move into the western Great Lakes by tonight. Afternoon/early evening instability showers and thunderstorms, mainly across northern Missouri will be possible as this upper trough makes its progress through the region. Consequently, isolated to widely scattered storms will be possible this afternoon and early evening but with a weakening upper trough and a loss of instability near sunset, storms will diminish. Height rises during the day tomorrow will help temperatures rise into the low to mid 80s. The main feature of interest will be an upper level trough over the southwestern CONUS.
322 PM MDT SAT MAY 28 2016 A modest amount of moisture will continue to be entrained over the region as the next low pressure system develops over southern California through Sunday.
Convection across the forecast area was mainly focused in the vicinity of a warm front in north central Wisconsin and a stationary front in western Wisconsin. Sunday Night Through Saturday Precipitation chances will be on the decline Sunday evening as a mid level short wave with surface cold front shifts east of the area.
However, an approaching s/w trough may initiate convection over the higher terrain of Mexico later this afternoon/early evening. Upper level ridge will then become established on Sunday across the area. The high risk of currents will continue through this evening due moderate southeast winds and long period swells.
Thunderstorms will be scattered this afternoon, but are expected to become more widespread this evening as the low-level jet kicks in and helps to congeal this activity into a larger cluster. Rain chances will continue through a large part of the extended Sunday night, an upper level low across southern California will slowly move toward Arizona, with West Central Texas in southwest flow aloft.
There has been some lightning north of Pembina ND in southern Manitoba and some down near Mobridge SD. Current boundary(northern extent of inverted trough from southern low) through the valley is expected to drift slightly west today as more persistent NE surface flow develops. Also ridging into the central Dakotas will limit pcpn potential over the far western fa. As upper low continues to lift east tonight pcpn should be ending from W-E overnight. Minimum temperatures Sunday night will be a bit cooler with clearing. Temperatures should be able to rise into the upper 70s most areas with warmer column and solar.
335 PM CDT SAT MAY 28 2016 Prefrontal trof to slide through forecast area this evening. Otherwise, will see storms weaken after sunset, then partly cloudy with lows in the low to mid 60s. Byrd Quieter weather is expected on Sunday as the upper level trough shifts northeast of our area. Slightly cooler low temperatures are expected for Sunday night due to less cloud cover, light or calm surface winds, and a little lower surface dew points.
Weak high pressure is ridging down the state as TD2 lifts NW toward the SE US coastline with an upper trough over the state. The upper trough will remain across the state through the period as TD2 continue to move toward the coast and the weak high pressure ridging over the area builds more over the Gulf of Mexico. Light winds will allow for an afternoon sea breeze on Sunday and increasing moisture will allow for scattered showers and thunderstorms with the highest chances across the southern half of the area and mainly inland of I-75.
A weak cold front will move across the area Sunday bringing a renewed chance of showers and thunderstorms. Fair weather is expected for Memorial Day as high pressure builds in behind the front. Temperatures will remain above normal with highs in the lower to middle 80s and lows in the lower to middle 60s. Focus will shift back west late as slightly stronger short wave and surface cold front begin to approach. Upper low expected to lift northeast into the western Great Lakes on Sunday while dampening. Associated weak surface cold front will move across the area.
Memorial Day, the weakness aloft moves east with much warmer air aloft.
A Hot ridge runs from western Mexico through Arizona and terminates over Nevada. To the north a trough runs the north/south extent of British Columbia In between a zonal to slightly southwestern flow has set up over the Pacific Northwest and high plains of Wyoming and Montana. warm air is expected to advect in from the south aloft forcing a little bit of a meso-ridge during these 24 hours and keeping shower and thunderstorms activity minimal if not nonexistent. Meanwhile, the trough to the northwest will dislodge and begin moving inland over Alberta ans western Montana.
Our region remains between weak high pressure across the Southern Appalachians, TD2 about 150mi SSE of Charleston SC and an approaching mid level disturbance across the Mid Mississippi River Valley.
This quieter pattern to remain in place the next couple of days as weak ridging aloft holds over the state. The break- down of the upper ridge on Tues should herald the approach/passage of the upper trof/low around mid-week. This system combined with a late season cold front will help to produce widespread activity as these systems appear to meet in SE TX. 41 Winds/seas over the coastal waters continuing to trend downward as high pressure continues to build into the region. No real change with this pattern is fore- cast until weeks end with the possibility of a cold front.
High pressure should result in dry weather for Memorial Day.
311 PM EDT SAT MAY 28 2016 A ridge of high pressure will remain centered over Pa this afternoon through Sunday.
Otherwise expect lows to drop to upper 50s to lower 60s as slightly cooler air moves in following a weak trough/cool front.
317 PM CDT SAT MAY 28 2016 A somewhat stacked area of low pressure over the Northern Plains will lift from the South Dakota and Iowa border region, as of this afternoon, to western Lake Superior by later tonight. The low brought a surge of moisture into the Northland, and scattered showers are expected to continue through tonight and Sunday morning as the low lifts through the region. Overnight lows should range from the upper 40s near Lake Superior to the low to middle 50s inland. May need to lower to the low 60s for next forecast.
Upper low is on the move and is now into southeastern South Dakota. Models open it up as a wave later tonight and the trough axis should be out of western Wisconsin Sunday mid morning. Brief upper ridging takes place, but with relatively zonal flow from the Pacific coast to the Upper Midwest, it appears that a weak short wave will move across the Dakotas Sunday afternoon. With not much shear, decent low level lapse rates and some instability, a boundary in the area, and upper low just west of us, it is possible there may be a funnel cloud or two and maybe even a landspout tornado.
Convection has developed over northeast Mississippi ahead of short wave trof near the Mississippi river. Mid to high level clouds will continue over central Alabama overnight as the short wave trof moves eastward, and possibly some light rain, but confidence on placement and timing not enough to include in forecast. Flow from surface through mid levels becomes northerly on Sunday and drier mid level air moves in from the north as the aforementioned short wave trof shifts into Georgia.
A somewhat stacked area of low pressure over the Northern Plains will lift from the South Dakota and Iowa border region, as of this afternoon, to western Lake Superior by later tonight. The low brought a surge of moisture into the Northland, and scattered showers are expected to continue through tonight and Sunday morning as the low lifts through the region. Overnight lows should range from the upper 40s near Lake Superior to the low to middle 50s inland. May need to lower to the low 60s for next forecast.
315 PM EDT SAT MAY 28 2016 High pressure over the region will weaken as a weak cold front moves across the area on Sunday. High pressure will return to the region for the first part of the week. With the approaching front and the weakening ridge, I will not completely rule out the chance of a few storms overnight but I will lower the proablilities into the slight chance category A weak cold front will move across the forecast area on Sunday. Temperatures will be slightly cooler on Sunday as cloud cover and thunderstorms are expected with the frontal passage.
331 PM CDT SAT MAY 28 2016 Water vapor imagery shows an upper level low now up in the northern plains with trailing trough now along and east of the Mississippi River Valley. Therefore, less convective activity is taking place today, and as we near max daytime heating, just some isolated activity is developing near the Lakes Area of southeast Texas and southwest Louisiana, as well as the lower Atchafalaya Basin. The upper level low over the northern plains will continue to open up and move further to the north-northeast, meanwhile, an upper level low off the Pacific coast will move into the southwest U. This will help build upper level ridging from northern old Mexico across the forecast area.
The main trough axis is expected to move through on Sunday, bringing a chance for a few showers and storms.
At 14 UTC this morning, our region was located between weak high pressure across the Southern Appalachians, TD2 about 225 SSE of Charleston SC and an approaching mid level disturbance across the Mid Mississippi River Valley. Given good run to run consistency in the hi-res guidance, will continue the low end PoPs in the Panhandle sea breeze zone. Should be a warm day, especially across South Georgia and the Florida Big Bend, where highs will be in the lower 90s.
I increased today's Max Temperature by a couple of degrees over the extreme east and west boundaries of our area as they have seen a bit more sunshine than the central portion of Middle Tennessee and they are trending warmer than the previous forecast suggested.
Early afternoon water vapor imagery and RAP 500 MB analysis show an upper level trough moving eastward across southeastern LA into western MS. The upper level trough will gradually approach southeast MS and southwest AL this afternoon, before models weaken/dampen this feature as it progresses eastward across the remainder of the region tonight. Isolated to scattered showers and thunderstorms will remain possible through the late afternoon hours, and kept the best chance over southeast MS in the vicinity of the approaching trough. Ridging aloft should promote very warm temperatures across the forecast area Sunday afternoon, with highs ranging from the upper 80s near the beaches to the lower 90s inland.
However, the current strength of the northerly surface flow at least across northern California will eventually push the low clouds into the salinas valley, after they have rounded the corner into the Monterey Bay. The surface flow is forecast to become stronger onshore tomorrow with current temperatures becoming cooler, especially near the coast, where upper 50s to mid 60s are expected. High pressure aloft will quickly rebuild on Memorial Day with temperatures rebounding with warm highs expected through the rest of the week. SFO Bridge Approach. A broad thermal trough will maintain gusty northwest winds over the waters through the weekend.
Weak pressure gradient between the "troughing" extending southwest from TD2 and weak high pressure ridging from the Southeast U.
Will be warmer on Sunday as surface flow is more downslopish and temperatures reach the 70s.
Could see elevated storms by late Sunday night between the Missouri River and I-90, as 850mb warm front begins to lift northward ahead of next mid-upper level trough approaching the area.
High pressure should result in dry weather for Memorial Day. Ridging aloft will be the dominant feature and keep most activity at bay despite the unseasonably warm surface temperatures and dewpoints in the mid 60s. Have maintained slight chances through early evening with the best chances over the ridges and western zones farther out and west of the ridge axis.
Lingering rain chances decrease and temperatures increase as high pressure takes control for the rest of the week.
This is advecting much drier air in the lower levels into Dekalb and eastern Jackson counties in northeast Alabama. This will shift and enhance the low level convergence westward to near the I-65 corridor through 18Z. Temperatures in these areas are only in the lower 70s to near 80 degrees.
124 PM MDT SAT MAY 28 2016 Visible satellite this afternoon shows cu developing across the entire area but a bit more organized upstream near the Cheyenne Ridge. Latest runs of the hires models suggest isolated showers/thunderstorms will drift southeast from the Cheyenne Ridge before dissipating around sunset. A storm or two could briefly pulse up to near severe limits in that environment but overall the severe threat will be on the low end for Sunday afternoon.
At 230 PM, South Central Texas surface analysis showed temperatures ranging from the mid 80s to low 90s with dewpoints in the low to mid 70s, showing the entire CWA as quite moist and unstable. While the upper level support is lacking currently due to broad ridging overhead. This weak upper level support coupled with the high instability, decent shear, steep lapse rates, and theta-e convergence along the dry line, think the slight risk area is laid out well for this afternoon and evening.
315 PM CDT SAT MAY 28 2016 Upper low over northwest Iowa at 19z with scattered showers and thunderstorms across eastern Nebraska and southwest Iowa. Dry conditions for the area tonight into early Sunday as upper flow flattens behind the departing trough.
With a remnant pocket of cooler air aloft lingering across portions of the region, diurnally driven cumulus developed this afternoon with ample insolation.
355 PM EDT SAT MAY 28 2016 An area of low pressure is centered near the coast of South Carolina. Forecast models are in general agreement, tropical low pressure near the south carolina coast resulting in increasing cloudiness across the carolinas overnight and a northwest drift of showers from the coast. Not confident of much precip making it into WVA or far western Va so will maintain a tight gradient of POPs west of the Blue Ridge. High humidity and showers will be in the forecast as long as it remains with highest pops along and east of the Blue Ridge, and lowest in the west. With more breaks in the cloud cover, temperatures should be warmer with 80s for highs.
Shower and thunderstorm coverage on Sunday is anticipated to be isolated at best as weak upper level ridging builds in and main triggering mechanism will be daytime instability with very little shear. Medium to long range models indicate shower and thunderstorm coverage will increase towards mid to late week as an upper level trough and associated cold front approach the Lower Mississippi Valley.
323 PM CDT SAT MAY 28 2016 A somewhat stacked area of low pressure over the Northern Plains will lift from the South Dakota and Iowa border region, as of this afternoon, to western Lake Superior by later tonight. The low brought a surge of moisture into the Northland, and scattered showers are expected to continue through tonight and Sunday morning as the low lifts through the region. Overnight lows should range from the upper 40s near Lake Superior to the low to middle 50s inland. May need to lower to the low 60s for next forecast.
335 PM CDT SAT MAY 28 2016 A weak cold front is working its way east through the CWA early this afternoon. Temps tonight should fall into the low to mid 60s, with somewhat drier air building in from the northwest. This slightly drier airmass, along with a bit of ridging aloft, should help temper thunderstorm chances significantly through the day Sunday.
From the late afternoon through evening hours, a weak front will make its way through the lower Ohio Valley.
A weak cold front will move across the area Sunday bringing a renewed chance of showers and thunderstorms. Fair weather is expected for Memorial Day as high pressure builds in behind the front. Temperatures will remain above normal with highs in the lower to middle 80s and lows in the lower to middle 60s. Mainly dry/mild otherwise into tonight with expectations for convection that fires late afternoon across Iowa/western Illinois on eastern fringe of Upper Midwest low pressure system to weaken/fall apart before reaching Indiana. This feature will force a cold front southeast into the area Sunday afternoon bringing additional low chances for convection. However, there will once again be substantial limiting factors for more widespread/organized development along this feature as deeper moisture, more favorable upper level support, and pre-frontal trough likely exits east by peak heating.
Temps tomorrow will be dependent on how thick the high/midlevel clouds will be.
212 PM CDT SAT MAY 28 2016 Satellite Water Vapor Imagery showing closed low vicinity of KFSD with a trough extending southeast through central IA. Ascent/lift ahead of this low combined with fairly humid airmass was leading to scattered shower/thunderstorms across the area per latest radar trends. will likely continue to see isolated showers through the overnight hours with mid-level trough moving overhead. Trough lingers overhead Sunday for more showers and late morning/afternoon scattered thunderstorms. Look for the trough to push east of the area Sunday night with weak ridging building in for clearing skies. Will see a chance of showers/thunderstorms mainly west of the Mississippi River on Memorial Day in warm air advection/isentropic lift ahead of low pressure moving into the Northern Plains.
An upper level short trof over west Alabama continues to march eastward, but was encountering much drier air over east Alabama. Another upper level trof near the Mississippi river will trigger scattered showers and thunderstorms over west Alabama this afternoon near axis of deeper moisture. A weak upper level short wave trof will approach west Alabama this afternoon. The short wave trof will produce mid/high level clouds tonight and across east Alabama after 12z.
The passage of this upper feature will push a weak cold front through the area by early Sunday.
Morning temperatures are running warmer than yesterday at this time by several degrees as readings are ranging from the mid 50s to lower 60s across the district.
114 PM MDT SAT MAY 28 2016 Visible satellite this afternoon shows cu developing across the entire area but a bit more organized upstream near the Cheyenne Ridge. Latest runs of the hires models suggest isolated showers/thunderstorms will drift southeast from the Cheyenne Ridge before dissipating around sunset. A storm or two could briefly pulse up to near severe limits in that environment but overall the severe threat will be on the low end for Sunday afternoon.
The NAM hints at a disturbance pushing around the upper ridge that is just to our west and uses it to develop overnight convection. Skies ahead of the dryline will be broken to overcast (mostly in the lower levels).