Aikyam-Lab/Synoptic-Bench huggingface dataset:
Low pressure pulls off to the northeast today, but scattered to numerous showers and some thunderstorms are expected once again. The upper low that has been centered across middle and eastern Tennessee this week was finally weakening and starting to shift north into the eastern Ohio Valley. In the evening showers will decrease pretty quickly with heating loss and the northward shift of the upper low. Rainfall amounts will be mostly light but could be up to an inch in the higher elevations with thunderstorms.
The low will situate just to the west of Pittsburgh this afternoon, over central Ohio. This will lend to marginal conditions for efficient rain production and flash flooding, although storm motion around 15-20 mph on the fringes of the upper low should be just enough to keep flash flooding threats low probability. Highs will remain below average under the upper low. It appears that weaker forcing on the backside of the upper low will reducing flooding threats from the day prior with lower storm coverage and decreased probability of training.
Lingering cloud cover will keep lows in the low to mid 70s tonight. Upper low over the Great Lakes and corresponding longwave trough over the eastern CONUS weakens and slowly lifts northeastward as another upper low treks across the northern Plains.
631 AM CDT Fri Jun 23 2023 Today and Tonight: With a ridge of high pressure centered over the Southern and Central High Plains today, and an upper-level low pressure system spinning over the Ohio River Valley, our forecast area will be positioned below northwest flow aloft.
637 AM EDT Fri Jun 23 2023 The upper low will shift north today with drier air working into northern and western areas while moisture hangs on across the south and east near a frontal boundary.
646 AM CDT Fri Jun 23 2023 (Today through Saturday) The upper low has moved away and we will see the ridge slide east a touch more through Saturday.
516 AM PDT Fri Jun 23 2023 Cooler than normal temperatures into the weekend, but gradually warming. Upper low is exiting the area this morning and will move from Nevada into the Great Basin Region by late this afternoon. Broad trough remains over the Eastern Pacific continuing the onshore southwest flow, which is providing cool and much below normal high temperatures.
Deterministic models are in pretty solid agreement that a broad upper-level trough and associated low pressure system will make way across Northern Idaho/Southern Montana, bringing widespread rainfall across predominately Central and Southwest Montana this afternoon through Saturday. Despite the higher MUCAPE values, shear values are far less impressive, meaning any thunderstorm that develops will essentially rain itself out.
The upper level low that has been responsible for all of this week's rain has started pulling away from the mid-state and while this will lead to more sun and warmer, dry conditions for most, I think the Cumberland Plateau may still see a few showers this afternoon. However, once we get into the evening hours, this will end and everybody will be dry Saturday -- with temperatures climbing into the low 90s for many.
Dry weather will persist through Saturday as high pressure remains in place across the region.
A persistent upper trough extends from the Pacific NW into NV and N CA with upper lows over central NV and WA. The trough is forecast to reposition a bit farther to the NW over the next few days and weaken. The coverage of thunderstorm activity is forecast to wane a bit each day as the upper trough sets up farther NW.
850mb temps support highs similar to yesterday, but the thicker smoke could cut a little into the highs over eastern WI. The more widespread shower and storm activity arrives from west to east after 5PM as the vertically stacked low pressure approaches from the west. One more very warm day expected with highs in the 80s to around 90, with slightly cooler readings near Lake Michigan.
In a nutshell, the presence of incoming moisture and meandering area of low pressure aloft will keep rain chances in the forecast through Saturday. An upper level trough axis will be over or just east of the CWA to begin the period Saturday morning, with increasing northwest flow as a jet stream moves over the area by Saturday evening in association with an approaching upper ridge. One more day of action from this system is forecast as heating/destabilization occurs on Saturday, with the highest PoPs being over extreme eastern KY, closest to the departing upper level trough axis. As this happens, another upper low (currently off the CA coast) will be progressing eastward over the northern Rockies and northern plains.
Dew points right now hover in the lower 60s. Winds will be light out of the north to northwest today, circulating around low pressure that drifts across the Mid Ohio Valley. Dew points may mix down into the upper 50s north and west, but may linger in the lower 60s south and east. Nevertheless, we'll carry NBM PPI01 Pops audible east closer to the low, tapering off to silent (but not zero) further west/away from the low. This will help temps soar into the lower half of the 90s. Winds turn around to a southerly component and that starts to tic the dew points up into the low-mid 60s by the end of the day, though some upper 50s/around 60 readings may hold in our northern parts. The ridges break down upon its advance, and dew points breach the 70F barrier.
104 PM CDT Fri Jun 23 2023 A warmer day is expected across the Mid-South today as southwest winds advect increased moisture and temperatures to the region.
1249 PM EDT Fri Jun 23 2023 A slowly traversing upper low brings unseasonably cool temperatures and chances for showers through Saturday.
Upper low over the Great Basin will approach the region this afternoon. WV imagery this afternoon indicates an upper low over the Great Basin approaching the Rockies. Broad ascent is evident surrounding the low. Slightly cooler over northeastern WY, with temperatures in the 60s and dew points largely in the upper 50s. Some northward retreat of the aforementioned front as a warm front is anticipated this afternoon and evening. Forward speed of the upper low slows somewhat tomorrow as it progresses eastward over the Dakotas.
241 PM MDT Fri Jun 23 2023 With the upper-level low pressure system now moving from Idaho into Wyoming, afternoon thunderstorms have already become widespread through northern Wyoming and southern Montana.
1201 PM CDT Fri Jun 23 2023 (Rest of Today) As of late this morning, fog is dissipating across our NE AL and S Mid TN regions, allowing for a decrease in cloud cover, especially along the ridgetops. With high pressure at the surface building back in, subsidence will limit afternoon cloud cover and subsequently rain chances given the dry profile shown on model soundings.
248 PM EDT Fri Jun 23 2023 Upper level trough axis resides east of the Jackson CWA along the spine of the central and southern Appalachians this afternoon, and continues to move away slowly, though disturbances will continue to rotate through the backside of the low across eastern Kentucky through Saturday morning.
(Tonight) Sfc analysis shows high pressure over the ArkLaMiss building to the NE toward the area, as the pesky H5 low of recent days finally meandering away from the area toward the Ern Great Lakes this aftn. Morning lows will fall into the lower/middle 60s.
A general lull in shower coverage continues late this morning as drier air pivots around the upper low situated immediately west of the area. Highs will remain a few degrees below average under the upper low. It appears that weaker forcing on the backside of the upper low will reducing flooding threats from the day prior with lower storm coverage and decreased probability of training.
Early this afternoon, the low ceilings will be replaced with a cu field between 4000-5000 ft. King (Today through Saturday) Drier changes will finally begin to manifest today as the pesky lingering upper low slowly lifts northward. As the upper low continues to open and lift into the Northeast U.
Otherwise clear skies and light winds will dominate into Saturday as high pressure moves from the Upper Great Lakes region eastward.
331 PM EDT Fri Jun 23 2023 An upper level low over the eastern CONUS is lifting north into the Lower Great Lakes today, weakening the ridge aloft. Therefore, updrafts are struggling to maintain themselves and the first thunderstorm of the day displayed a near-perfectly symmetrical outflow boundary and divergent velocity signature at the lowest tilt. Upper air pattern consists of a 500 mb closed low in the northern plains 12z Sat which moves into the upper Great Lakes on Sun and into the lower Great Lakes on Mon.
As the system moves into the High Plains this evening, enhanced deep layer shear will develop over parts of western/southern South Dakota. The north central and northeast parts of the state have the lowest chances for severe since that area is displaced to the north of the better shear/instability. The upper low should then track across the Dakotas on Saturday, with continued chances for mainly diabatically driven activity under cooler temps aloft.
Marquardt (Issued 314 AM CDT Fri Jun 23 2023) Today through Saturday: Another dry and warm day today as high pressure continues over the area. Southerly winds return Saturday which will help temperatures be a few degrees warmer with highs in the upper 80s to low 90s across much of the area. Expect cooler temperatures along the lake.
247 PM EDT Fri Jun 23 2023 Low pressure over the Lake Erie will slowly move northeast across New England this weekend.
(This afternoon through Saturday Night) The upper low continues to pull off to the northeast this afternoon with the center over Lake Erie as seen on water vapor.
Dewpoints in the low to mid 70s will begin pushing into the area from the southwest by mid morning with heat indices rising to near 100 by noon. Current hi-res guidance show a short wave trough shifting east/northeast across the upper east coast. At the same ridging continues to build across the southeast US as the trough axis lifts further east towards the Carolinas. Because of this, drier air should continue to hover over much of central Mississippi which should help dewpoints peak in the low to mid 70s. These higher dewpoints should help afternoon temperatures peak in the low to mid 90s across the area for much of the weekend.
/ISSUED 528 AM MDT Fri Jun 23 2023/ Deterministic models are in pretty solid agreement that a broad upper-level trough and associated low pressure system will make way across Northern Idaho/Southern Montana, bringing widespread rainfall across predominately Central and Southwest Montana this afternoon through Saturday. Despite the higher MUCAPE values, shear values are far less impressive, meaning any thunderstorm that develops will essentially rain itself out.
Later this afternoon, thunderstorms are expected to initiate over the higher elevations of southern Montana and northern Wyoming, then increase in coverage and intensity as the evening wears on. ---BMickelson Previous discussion: SW flow aloft will bring moisture into the forecast area today as a low pressure system develops over Wyoming. This trough will become a closed upper low along the MT/WY border in SE MT and NE WY late tonight with heavy rain along and north of this low track across southern MT and northern WY.
- Cooler end to weekend and start to new week with lingering shower and thunderstorm chances. Tonight through Saturday Night: Besides a widely scattered shower or two between LSE and MSP associated with weak boundary in the area, quiet weather still prevails as persistent ridge continues to weaken. But with this weakening, plus approaching mid level short wave trough, convective threats will be on the increase heading into the weekend. One scenario is early morning convection erodes before it arrives allowing for a cleaner air mass and stronger convection a bit further north and east as main mid level trough approaches late Saturday afternoon.
205 PM EDT Fri Jun 23 2023 The upper low will shift north today with drier air working into northern and western areas while moisture hangs on across the south and east near a frontal boundary.
Hi-res models take the storms NNE and out of our CWA by noon but more showers and thunderstorms will develop this afternoon due to an upper low in eastern NV. A chance of afternoon-evening showers and thunderstorms over the higher terrain and southeast OR. There is a slight chance that thunderstorms will drift across the lower elevations, including the Snake Plain.
Temperatures will be on the rise once again as high pressure builds over the region, possibly bringing Las Vegas its first 100 degree day. The upper level low responsible for last night's thunderstorms in California and northern Nevada exited to the northeast this morning, leaving a ridge of high pressure over the Southwest U. and a trough off the Pacific Coast.
Hi-res models show another 4-6 hours for best convective coverage before the trough begins to move well east of the region allowing conditions to improve.
As the low moves eastward during the day Saturday, showers become more scattered.
Water vapor imagery highlights a mid to upper-level trough centered over the Ohio River Valley. The southern extent of this trough reaches into the northeastern Gulf of Mexico. Low-level ridging centered near Bermuda reaches west-southeast across South Florida, although there is a notable, weakly inverted divot sliding west-northwest out of the Cay Sal Bank. Highs across the island chain are in the lower 90s, with dewpoints near 80. Some locations briefly registered heat indices in the low 110s, as mid to upper-level cloud cover eroded. Mean-layer ridging centered to the northeast of the Bahamas and also over northern Mexico/Texas, will remain split by lower heights in the northeastern Gulf.
/16 (Now through Saturday) The closed upper low embedded in an upper level trough over the eastern Conus moves off today, leaving the upper trough. The upper trough begins to fill Saturday into the weekend, with upper level high pressure centered over Texas/Mexico beginning to build east over the northern Gulf coast.
Deep mixing this afternoon will likely place a limit of dew points in the low to mid 50s this afternoon. With a strengthening subsidence inversion advancing eastward ahead of an approaching mid-level ridge, convective depths within any growing cumulus will diminish.
Dry and trending warmer otherwise tonight into Saturday, with highs into the mid to upper 80s.
After this initial mid level wave transitions east tonight there may be a lull in shower/storm coverage and intensity, before the main mid/upper low kicks east across the Dakotas. Broadly speaking the higher totals in the 2-3" range are more likely where thunderstorms track, but within the deformation zone the probs for 1" or more of rainfall have zero in and are now in the 60-90% range.
(Rest of tonight) A weak area of high pressure remains in place over much of Mississippi, Alabama, and Georgia this evening. Despite reaching the lower to mid 80s earlier this afternoon, clearer skies and light winds have allowed temperatures to drop into the upper 60s to around 70 degrees in some locations. Also, it should keep temperatures from dropping much below the mid 60s, so tweaked lows a bit warmer.
815 PM EDT Fri Jun 23 2023 23Z sfc analysis shows weak low pressure over the region which is keeping the threat of showers around, mainly in the east. Upper level trough axis resides east of the Jackson CWA along the spine of the central and southern Appalachians this afternoon, and continues to move away slowly, though disturbances will continue to rotate through the backside of the low across eastern Kentucky through Saturday morning.
The forecast is still on track for tonight into Saturday morning/afternoon as high pressure exits the Great Lakes Region. Otherwise clear skies and light winds will dominate into Saturday as high pressure moves from the Upper Great Lakes region eastward.
925 PM EDT Fri Jun 23 2023 Shower chances will taper off tonight, but will increase again on Saturday as low pressure slowly moves across the Upper Ohio Valley region.
A trough axis was located from KLHX down toward east of KTAD. A broken line of cumulus were bubbling along the trough axis. Behind the trough/dryline axis, it was quite warm and windy. The primary threat for our region will be hail as the low level hodographs will likely not get favorable until the storms push into KS, but nonetheless I cannot rule out a tornado and some strong downburst winds. Min temps will be cooler than last several days as the ambient sfc airmass will be much drier over the region. This much drier air can clearly be seen on the lower level water vapor channels that is moving into teh region.
606 PM CDT Fri Jun 23 2023 (This afternoon through Saturday Night) The upper low continues to pull off to the northeast this afternoon with the center over Lake Erie as seen on water vapor.
With ~20 to 25 knots of deep layer shear and ~1500-2000J/kg of mlCAPE to work with, a few of these storms have had weak mid-level mesocyclones and tried to build up enough to be capable of marginally severe hail. As the system moves into the High Plains this evening, enhanced deep layer shear will develop over parts of western/southern South Dakota. The north central and northeast parts of the state have the lowest chances for severe since that area is displaced to the north of the better shear/instability. The upper low should then track across the Dakotas on Saturday, with continued chances for mainly diabatically driven activity under cooler temps aloft.
Scattered convection associated with a cut-off upper low over Lk Erie should diminish in coverage/intensity overnight as boundary layer cools. The focus of additional showers overnight should be across the northwestern counties, closest to the upper low. Model soundings supports a low overcast across the region tonight, with ridgetops shrouded in fog. After a relative lull in precip/convection during the morning hours, expect diurnal convection to fire by afternoon under the remnants of the upper low. With the upper low overhead, some hail is also possible from the taller towers.
Currently - A surface through mid level Atlantic ridge has become better established across Florida. Short Term Update - Surface through lower level ridging will continue to dominate Keys weather through the overnight period.
A weak upper low aloft has allowed enough instability for isolated showers and thunderstorms to form across southeast Oregon and west-central Idaho this afternoon and evening. Re-development of storms are anticipated Saturday afternoon as southwest flow develops aloft, with the higher terrain and eastern Oregon being the most favored locations. Temperatures will trend warmer for the weekend. Scattered showers and isolated thunderstorms return Saturday afternoon that will persist through the evening, mainly over the higher terrain. There is a small threat that thunderstorms will drift across the lower elevations, and this would include the Snake Plain.
Center of the Low's vorticity looks to be over KBYZ and slowly beginning an eastward trek. THis will drag the rainshowers along the northern side of it across Petroleum, Garfield, and the lower Yellowstone Valley with it. GAH AFTERNOON DISCUSSION: With the upper-level low pressure system now moving from Idaho into Wyoming, afternoon thunderstorms have already become widespread through northern Wyoming and southern Montana.
629 PM CDT Fri Jun 23 2023 (Tonight) Sfc analysis shows high pressure over the ArkLaMiss building to the NE toward the area, as the pesky H5 low of recent days finally meandering away from the area toward the Ern Great Lakes this aftn. Morning lows will fall into the lower/middle 60s.
751 PM EDT Fri Jun 23 2023 Dry and trending warmer Saturday with highs into the mid to upper 80s.
5 Widespread rain was lifting northeast out of the area early this morning as the upper level low transits the region. For tonight, look for low temperatures in the low to mid 30s. A longwave trough axis will be centered across the Plains Saturday afternoon before shifting east throughout the evening and overnight hours.
Upper troughing digging into the Rockies and Plains over the weekend will bring some high and mid clouds, but not much else to our area. Thus, leaned a bit on the higher side of the ensemble spread and have mid 30s for highs across much of the ND side, and some upper 30s not out of the question. The winds and periodic cloud cover will also keep overnight lows warmer than climo, staying in the upper teens and low 20s.
258 PM CST Fri Dec 1 2023 - Areas of dense freezing fog are expected early Saturday morning.
There may also be some fog/freezing fog moving into the eastern/southeastern parts of the forecast area after midnight. Low temperatures will range from the lower teens to lower 20s. Northwest winds increase behind the departing upper trough axis with gusts in the 25 to 35 mph range, mainly west of Highway 27. High temperatures are forecast to be in the lower to upper 40s.
Issued by National Weather Service Green Bay WI 355 PM EST Fri Dec 1 2023 Key message: Dry and seasonable weather expected through Saturday High clouds are expected over the eastern half of the Upper Peninsulatonight on the northern edge of a low pressure system over Illinois. Clouds will increase from west to east Saturday as an upper trough approaches from the Northern Plains.
As this occurs, the system's related surface cyclone will weaken as it tracks more slowly northeastward from central MO into central IL.
1136 AM CST Fri Dec 1 2023 * Some residual light precipitation(rain/snow mix) will be possible across central Kansas later this morning/afternoon, no accumulation expected * Possible fog for late tonight into Saturday morning due to recent rainfall and light easterly winds across southern Kansas * Cool below normal temperatures will continue on Saturday * Warmer temperatures will return to Kansas Tdy-Sun Current satellite water vapor imagery shows upper level system moving northeast towards Missouri early this morning which will cause the precipitation to quickly taper off over eastern Kansas. Daytime highs will be cooler than normal for today with low clouds eroding from west to east later in the day. The upper trough axis will remain over the central plains through the weekend with yet another embedded upper wave moving across the region on Saturday.
1114 AM CST Fri Dec 1 2023 (Today and tonight) Strong southwesterly flow aloft will continue over the southern Great Plains region today as an H3 jet streak remains essentially stationary along the leading edge of broad upper level troughing over most of the western CONUS. In general, the westerly downslope component to the low level flow combined with a very modest increase in layer thicknesses will allow for a slightly warmer day compared to yesterday across most of the region.
Tomorrow is expected to be slightly warmer, with highs in the mid 30s to lower 40s.
Visible satellite imagery continues to detect a relatively chaotic cloud pattern across the forecast area, with fair weather cumulus clouds advecting from the east to southeast in the low-level steering flow, with mid- and high- level clouds pushing in from the west associated with a lifting upper level trough to the north of the Gulf of Mexico. High pressure continuing to slide eastward in the west-central Atlantic will largely dictate the sensible weather forecast through the weekend.