Aikyam-Lab/Synoptic-Bench huggingface dataset:
A deepening upper low will move southeast from over the Upper Midwest to the mid Mississippi Valley region today through Monday. While there is modest flow with this upper low, the instability factor should be less. Given the prospects for added cloud cover and convective chances with the upper low, we have highs in the lower 80s for today and Monday, close to available guidance. Westward progression of the Bermuda High early this week will keep high pressure in place over the east coast.
Satellite early this morning shows the upper low swinging through the MS River Valley with wrap-around cloud cover and a few showers moving south into our area from NE. With another upper ridge off the eastern seaboard, our trough will be slow to move east today allowing for scattered wrap-around showers across the area through the day. Temperatures will be seasonally cool as northerly winds usher in cooler air, with highs in the 70s for most. Central KS has the best chance of reaching the low 80s as earlier clearing should allow for more insolation. The upper trough slowly pushes further east on Monday, although we will still be under its influence to an extent as northerly winds keep temperatures somewhat on the cooler side.
625 AM CDT Sun Jul 11 2021 A seasonally strong upper trof will deepen into a closed low today as it drifts south over Missouri. Moisture wrapping around the cyclonic flow within the thermal trof will result low clouds and modest diurnal instability across eastern Kansas, so plan to continue to show modest chance PoPs for locations east of I-135, along with temperatures well below seasonal climo. The closed upper low and trof axis across the mid-Mississippi Valley and Ozarks will be slow to move through Monday.
The high pressure centered over southern Nevada, and a closed low over the central US. Widespread smoke should keep temperatures a degree or two cooler than guidance so adjustments have been made accordingly. This could keep highs up to 5 degrees cooler than yesterday. It should result in scattered afternoon convection in the higher terrain.
The upper low responsible for the convection will pull northward through the week.
Climatologically hot weather continues for much of the interior today as upper-level ridging holds in place aloft. The inversion touching into the ridges of Lake and southeastern Mendocino tonight should once again result in minimum temperatures in the high 70s tonight, providing little reprieve from this afternoon's heat. although many valleys will see overnight lows reaching the high 60's to low 70's.
Early Morning Update: Over the last hour the warm front as quickly moved through central Ohio to the southern edge of Lake Erie. However, the confidence is on the low side that this will occur. Much of it based on how quickly and how far north the ridge progresses. The intrusion of the impressive ridge will provide a hot and humid Monday.
Due to this, have continued the Excessive Heat Watch for all areas below 6kft with the exception of the "cooler" Delta area. Stronger onshore flow is expected tonight and tomorrow which will bring cooler temperatures to portions of the southern Sacramento and northern San Joaquin Valleys, including areas near the Delta.
953 AM EDT Sun Jul 11 2021 A warm front will lift north through the area through this evening. Thereafter, Bermuda high pressure system will build through the first half of the week before it starts weakening during the second half. A cold front will approach the area at the end of the week. Low-level warm advection has led to quite a bit of low clouds east of the Blue Ridge and Catoctins. After a lull in the shower activity, additional showers and t-storms develop this afternoon as a warm front lifts through the area. Activity should wane quickly after 00Z tonight as a warm front lifts north into PA and forcing and instability wane. Even less convective cvrg is anticipated Tue as 500 mb ridge reaches maximum amplitude across the local area.
800 AM EDT Sun Jul 11 2021 Deep layer ridging from the Atlantic stretches across most of FL to the Gulf of Mexico through tonight as a upper low spins across the Mid-Mississippi Valley and a upper low/trough aloft the Bahamas tracks to south of the Florida keys. The ridge axis currently across central or north-central FL lifts into the north end of the state. Afternoon highs reach the lower 90s with the beaches a tad lower. High pressure across the waters lifts into Georgia by Mon and resides there for the week with prevailing winds becoming east or southeast.
This is because a Tropical Upper Tropospheric Trough (TUTT) is pivoting towards our area with a dry slot. With that said, convective allowing models (CAMs) show that the low levels, which will stay moist, may be able to overcome the drier air in the mid levels.
The high pressure centered over southern Nevada, and a closed low over the central US. This should keep temperatures a degree or two cooler than guidance so adjustments have been made accordingly. This could keep highs up to 5 degrees cooler than yesterday. It should result in scattered afternoon convection in the higher terrain.
Impacts are for Monday afternoon (and evening) when a few thunderstorms are possible along an eastward moving trough. Monday will see a 500 mb short wave trough move east from Saskatchewan and Montana east into Manitob and then eastern ND by 00z Tue. Forcing with this short wave trough isnt great, but temps of upper 80s/low 90s and dew pts near 60 along the trough will create MUCAPE values 1000-1500 j/kg into DVL basin mid aftn and into the nrn RRV Monday evening. As been the case with most of our events this summer, expect a period of scattered t-storms along the trough developing in the DVL basin mid aftn Monday and moving east into the northern RRV and far NW MN early Mon evening.
Looking aloft, an upper- level low is causing broad troughing across our area which is helping to keep any inhibition at bay.
1013 AM EDT Sun Jul 11 2021 A warm front will hang up just north of the local area today. Bermuda high pressure then extends into the the area for most of the upcoming week. Latest MSAS has the warm front lifting north across the area. While the low clouds/fog are slowly dissipating, sct convection quickly firing from the nrn neck sw to the NC Piedmont as a weak disturbance tracks across the area. Mild and muggy tonight with lows in the low to mid 70s. Bermuda high pressure dominates the weather pattern through midweek allowing for mainly dry and seasonably hot/muggy conditions.
Another area of elevated smoke is expected to approaches from the west ahead of Monday's cold front. Focusing now on Monday's cold front, still expecting some convection with this forcing mechanism as moves out of western ND into the area early Monday morning.
410 PM EDT Sun Jul 11 2021 A warm front draped near and just to the north of Route 322 in Western and Central PA this afternoon will drift slowly north through this evening, ushering in higher humidity and hotter temperatures for the beginning of the upcoming week. Target area for the heaviest rain (locally over 2 inches possible) and flash flooding concerns appears to be across the Ncent Mtns and portions of the Upper Mainstem of the Susq Valley where FFG values are the lowest and last few runs of the HRRR/RAP focus the best chc for two-three training TSRAs. However, some short wave ridging is in place for some of the day. Large scale upper level ridge across the western states will keep a weakness in the upper level flow over the eastern states for the new week.
Closed midlevel cyclone was spinning over NE Missouri at midday, with the cool/dry/stable (relative to midsummer) airmass being maintained/reinforced across SW Kansas. Afternoon temperatures will be well below normal, in the lower 80s north to the mid 80s near Oklahoma, with dewpoints slowly sinking through the 50s. Guidance is in good agreement regarding sunrise Monday temperatures in the mid 50s at many locations, a few notches cooler than the upper 50s observed this morning. Even some lower 50s are probable in the lower lying valleys of the northeast zones late tonight. Afternoon temperatures will bounce back to near normal in the lower 90s (a few degrees above 12z MOS guidance).
Monday will still be very hot over the northern end of the valley and many foothill/mountain areas in the thermal belt will remain very warm overnight but start to trend cooler.
These showers are thanks to a nearby upper low spinning away across central MO. One thing to look out for today (and tends to be common with a nearby upper low) would be the potential for brief funnels to develop within stronger updraft cores where stretching of vorticity can be maximized.
SHORT TERM (Tonight through Monday Night): We are finally getting a break from the rain and flooding! At 500 mb, high pressure from the Gulf and southwestern US will continue to build across deep south Texas allowing drier air to filter into the region. At the surface, high pressure over the Atlantic and low pressure over northern Mexico will allow for more moderate southeasterly winds, especially along the coast, into early evening.
Some fog may form in river valleys and low-lying areas again tonight with increasingly light flow in the low-levels, but the extent of mid/high clouds across the southeast half of the area on the periphery of the broad upper level trough could affect fog formation.
Warm and dry conditions should prevail as a general rule through Monday afternoon w/ substantial upper-level ridging remaining intact. A few very weak disturbances will likely traverse the flow along the edge of the ridge.
220 PM MDT Sun Jul 11 2021 Weak ridging continues to be the primary pattern. The weak ridging/zonal flow continues through tomorrow night. This wave will generally have the impact of producing peak heating showers and thunderstorms, starting along the higher elevations of the western mountains, before drifting east and northeast later in the afternoon.
An upper level Low is centered to our Northwest over Missouri with and upper level Ridge over the Western Atlantic. Mainly southerly flow at the surface will prevail for today, then shifting to the southeast overnight as the upper level ridge expands westward. High temperatures today and tomorrow will be in the upper 80s to low 90s, with lows in the low to mid 70s.
/issued 800 AM EDT Sun Jul 11 2021/ Deep layer ridging from the Atlantic stretches across most of FL to the Gulf of Mexico through tonight as a upper low spins across the Mid-Mississippi Valley and a upper low/trough aloft the Bahamas tracks to south of the Florida keys. The ridge axis currently across central or north-central FL lifts into the north end of the state. Afternoon highs reach the lower 90s with the beaches a tad lower. High pressure across the waters lifts into Georgia by Mon and resides there for the week with prevailing winds becoming east or southeast.
242 PM CDT Sun Jul 11 2021 500 hPa ridging aloft and high pressure at the surface have resulted in a very pleasant day. Temperatures tomorrow will be very similar to today, perhaps a degree or two warmer topping out in the lower to mid 80s.
(This evening through Monday) Slightly drier air has filtered south in the wake of the cold front that brought storms to much of the area last night.
Under the influence of the upper low, temperatures should remain below average for July. The upper low responsible for the convection will pull northward through the week.
238 PM MDT Sun Jul 11 2021 A weak upper trough will cross the area late tonight into early Monday. By early Monday afternoon, a cold front will advance southeastward across the area, with isolated showers and storms possible by late afternoon over the Black Hills.
155 PM CDT Sun Jul 11 2021 Upper level high pressure system remains parked over southern Nevada this afternoon keeping the FA in north-northeasterly flow aloft. Tomorrow the 597 dm upper level high to our west will expand back towards the area as south to southwesterly surface winds return. This will ultimately lead to drier and slightly warmer conditions to start the work week.
Along the I-20 corridor, we should have a chance to climb into the low 80s.
(This afternoon through Monday night) Have an upper ridge centered over Srn NV this morning with a trough over MO extending into the plains. This trough will trim the east edge of the ridge off as it moves south Monday. Lows tonight will mainly be in the 60s with afternoon highs Monday a couple degrees warmer.
327 PM EDT Sun Jul 11 2021 Atlantic high pressure will extend across the area through this weekend. Late Afternoon: Aloft, a low will be centered across the Midwest while a ridge strengthens across the western Atlantic. At the sfc, forcing mechanisms will remain limited, with a lack of a lee trough inland and a subtropical high expanding across the region. Low temps should be mild, ranging in the low-mid 70s inland to upper 70s at the beaches. Atlantic high pressure at the surface and aloft will prevail through the period, maintaining typical July weather. High pressure at the surface and aloft will maintain control of the local weather late week into the weekend. This Evening and Tonight: High pressure across the western Atlantic will extend across local waters through the night while an upper lvl low approaches the Florida coast late.
Rain and storm chances should gradually diminish by late Monday morning as high pressure builds in. Monday's high will be a few degrees cooler than Sunday, but still warm.
The steering flow is more northerly today with the center of the high just west of southern Nevada. As these outflows move westward they could tap into instability over the lower desert causing isolated strong thunderstorms over the Tucson metro this evening.
Later tonight through Monday, an upper level trough over the Southeast helping to aid today's convection will shift west as an mid/upper level ridge over the East Coast builds west over the Southeast. Convection has a good chance of forming in the early morning hours, with guidance advertising a weak 850 jet forming over northwestern portions of the Southeast late tonight into early Monday(and the forecast area) as the mid/upper level ridge builds west. Winds direction remains linear in the low to mid levels though, leading to more linear development of any convection that does form. Tonight, with the humid airmass in place, low temperatures a bit above normal are expected, bottoming out in the low to mid 70s inland, mid to upper 70s along the coast.
High pressure and dry low/mid level air remain solidly in control of the wx across the Northern Great Lakes this afternoon. Low pressure centered just north of the Ohio Valley continues to produce relatively weak convection north of the low center. High Impact Weather Potential: Low Pattern Synopsis: Dominant ridging will continue to hold firm over the SW CONUS into the middle of the week as a closed upper-level low centers itself over the mid-Mississippi Valley.
246 PM EDT Sun Jul 11 2021 Typical summer time pattern continues with the Bermuda High will ridging into the forecast area during the week. Temperatures remain around seasonal average with highs in the low 90s and lows in low to mid 70s. Bermuda high will be ridging into the region with the upper level ridge offshore and an upper level trough digging into the MS River Valley.
248 PM MDT Sun Jul 11 2021 Upper level ridge off to the west will slowly shift east over the next 24 hours. This will bring warmer temperatures for Monday. Precipitable water values will increase to around a half inch over the higher terrain. Storms will struggle to survive once they move off the higher terrain, so will have slight chance PoPs for the Urban Corridor and keep the plains dry.
A frontal boundary and upper level trough will cross the region Monday afternoon into Monday night.
Issued by National Weather Service Louisville KY 235 PM CDT Sun Jul 11 2021 Closed upper low over northern Missouri tonight will begin to open up on Monday, but only lift out as far as Wisconsin. With the trof axis extending south into Arkansas, this will maintain a deep and very moist southerly flow, supporting numerous showers and thunderstorms east of the Mississippi, especially on Monday afternoon. This mirrors the SE extent of the Slight Risk in WPC's excessive rainfall forecast and seems reasonable, but it's toward the lower end of impacts yet, so will not go with a Flood Watch at this time.
These lingering precip chances are associated with the upper level trough responsible for the active weather this weekend, which reaches its furthest southern extent around 06Z before beginning to lift to our north. However, the pronounced upper level ridge just off the Atlantic coast will serve as a blocking mechanism preventing the trough from making a speedy exit, hence the continued lower end precip chances through the day Monday and into the overnight hours.
LW Chattanooga Airport, TN 71 84 69 84 69 / 50 60 50 70 40 Knoxville McGhee Tyson Airport, TN 71 85 68 85 68 / 40 60 40 60 30 Oak Ridge, TN 70 84 67 84 68 / 40 60 40 60 30 Tri Cities Airport, TN 68 86 66 86 65 / 30 50 20 50 20.
A closed upper low across Missouri will gradually open up on Monday and head towards the western Great Lakes region. Later tonight, an upper level disturbance rotating around the upper low could clip our southern counties with a few showers, thus kept a small chance of rain in our far southern counties across central and east-central Wisconsin. A light east wind at Oshkosh may keep readings up in the lower 60s there due to the warmer waters of Lake Winnebago. Monday Night Through Sunday The weakening upper low lifting north from Illinois will be swept up with the upper trough moving across the Northern Great Lakes Monday night.
307 PM EDT Sun Jul 11 2021 Upper air pattern consists of a 500 mb ridge in the western U. into the Rockies and then along the Gulf Coast with a trough in the Pacific NW and a trough in the central plains through New England. The culprit for these changes is largely due to a ridge extending out of the Atlantic into the eastern CONUS. This ridge will force a cutoff low over the middle-Mississippi River Valley to lift northward. Dry air ahead of the low is also playing a part. Guidance is still suggesting the low to begin's its northward journey late Monday and devolve into a weak open wave.
A seasonally strong upper trof will deepen into a closed low today as it drifts south over Missouri. Moisture wrapping around the cyclonic flow within the thermal trof will result low clouds and modest diurnal instability across eastern Kansas, so plan to continue to show modest chance PoPs for locations east of I-135, along with temperatures well below seasonal climo. The closed upper low and trof axis across the mid-Mississippi Valley and Ozarks will be slow to move through Monday.
331 PM CDT Sun Jul 11 2021 A positively tilted upper ridge axis sits over the Northern Plains early this afternoon. At the surface, a broad expanse of high pressure extends from the Central High Plains to the western Great Lakes. Strong Q-vector convergence, mid level DCVA, and low level frontogenesis will likely provide enough forcing for scattered showers and thunderstorms along and ahead of the trough as it moves across the state from west to east tonight through Monday morning. The passage of the trough will lower temperatures by a few degrees on Monday, with highs mainly in the 80s.
Ridging will continue tonight before beginning to erode late tonight into tomorrow as a weak upper level trough digs into East Texas before lifting off into the northeast. With fewer clouds around, high temperatures tomorrow are expected to climb into the lower to upper 90s, from east to west. Despite the limited amount of moisture, the warmer temperatures combined with the available moisture could lead to heat indices around 105 degrees across portions of South Texas.
1119 AM MDT Sun Jul 11 2021 Area of high pressure being analyzed over Wyoming this morning with clear skies and light winds. Upper level pattern showing an area of high pressure over the desert southwest with ridging over Wyoming. Monsoonal moisture remains south of the high across northern old Mexico and southern Arizona. Warm and dry today and Monday as ridge of high pressure persists.
Rux PREVIOUS DISCUSSION: Synoptic Setup: A large ridge juts out from the Dome of hot high pressure over the Intermountain West. This ridge runs northeast through Idaho, Montana, southern Saskatchewan and Manitoba. Today and Tonight: Ridge line will exit east mid-morning allowing a cold front to enter by the afternoon hours. With the passage of the cold front clear air from northern Alberta should clear most of it.
122 PM CDT Sun Jul 11 2021 Upper low is currently situated over northern MO with a vort lobe swinging southeast across eastern KS. Meanwhile, upper ridging remains planted over the Desert Southwest. At the surface, upper ridging extends from the Upper Mississippi Valley down into the OK Panhandle. The culprit is an upper low spinning across Mid-America.
After any fog mixes out, another pleasant day is on tap for Monday with temperatures in the lower 80s again.
300 PM EDT Sun Jul 11 2021 Showers and thunderstorms appear promising today and tomorrow as a low pressure system stalls to our west. Increasing jet ascent, with frontogenesis in the low levels will support continued thunderstorm development this afternoon. The best favored area for rotating discrete cells will be near the I-80 corridor as it interacts with a warm front situated west to east in that area.
117 PM EDT Sun Jul 11 2021 Showers and thunderstorms appear promising today and tomorrow as a low pressure system stalls to our west. With lingering sunshine this morning and dew points increased into the low-70s, instability south and east of Pittsburgh has reached between 1200 and 2000J/kg.
Aside from that area, plenty of subsidence from the high pressure, centered over the Great Basin, has stopped any convection from developing this afternoon. This smoke is moving in from much of the PacNW and northern California, riding over the ridge and then drifting down into our neck of the woods.
204 PM CDT Sun Jul 11 2021 Quiet weather will continue across central and western Nebraska through Monday with the upper ridge slowly losing amplitude as a series of short waves crest the ridge. Highs on Monday will be noticeable warmer though dew points will lag a bit so humidity will not be oppressive. Any modest destabilization will be capped enough to inhibit convective development through Monday, though an isolated shower or thunderstorm may be possible Monday night as the low level wind field amplifies and enhances forcing with the environment continues to moisten.
126 PM EDT Sun Jul 11 2021 A warm front will hang up just north of the local area today. Bermuda high pressure then extends into the the area for most of the upcoming week. Latest MSAS has the warm front lifting north across the area. While the low clouds/fog are slowly dissipating, sct convection quickly firing from the nrn neck sw to the NC Piedmont as a weak disturbance tracks across the area. Mild and muggy tonight with lows in the low to mid 70s. Bermuda high pressure dominates the weather pattern through midweek allowing for mainly dry and seasonably hot/muggy conditions.
257 PM EDT Sun Jul 11 2021 GOES water vapor shows well defined upper low this afternoon across NW MO with a slow meander to the southwest. Moisture streaming northeast of this low into our local area with weak short waves moving through the mean southwest flow. Upper low to begin a slow drift northeast over next 24 hours and will eventually get absorbed by a short wave trough currently along the western US/Canada border that will be moving eastward and becoming a bit sharper with time. Models in good agreement on this scenario and have also slowed the eastward progression of residual trough that is left after phasing. Too much uncertainty on this low chance condition so no watches planned with this issuance.