Aikyam-Lab/Synoptic-Bench huggingface dataset:
646 AM CDT Mon May 8 2023 (Monday through Tuesday) Some pre-dawn convection has developed early this morning invof a theta-e ridge axis from Lower Toledo Bend country across central Louisiana. Despite upper ridging aloft extending southward from the Central Plains into the Southern Plains and Lower Mississippi Valley, several disturbances will move underneath the ridge over the CWA. If temps manage to get closer to 90 degrees, uncomfortable conditions could develop, as heat index values would climb into the low to possibly mid 90s.
604 AM CDT Mon May 8 2023 (Today and tonight) A cold front is moving into northern Oklahoma early this morning which will probably move south a little farther before stalling out across northern and western Oklahoma. Low-level temperatures will be warmer in the southwest near the dryline, so the cap will effectively be weaker than farther north. The primary signal along the warm front will be farther south today, so storm chances are less likely than the past couple of days across our Texas zones and southwest Oklahoma, but it is still worth some low POPs near the dryline in our southwestern counties.
The low clouds will likely hold tough, with some lingering fog and drizzle through the rest of the morning. 500 mb upper low center is over north central Minnesota early this morning and will lift slowly north or northwest toward the MN/ND/Manitoba border by this evening. Showers are more likely to the east and north side of the upper low which would keep likely pops out of our forecast area. Warmer temps as well with highs into the 60s all areas. Ensembles and cluster analysis depict an overall SW flow with increased ridging for a brief period this week.
An additional weak trough is progged to move through Tuesday as part of this more broad upper trough pattern centered over the Pacific Northwest. Guidance exhibits reasonable confidence that rain chances will be minimal from this second trough, being overall less dynamic and passing further to our south, leaving much of the Bay Area and Central Coast on the drier side.
Cold front will move through the area this afternoon with cooler high temperatures today. The cold front is forecast to exit the area fully by 21 UTC with some lifting of the clouds behind the front. High pressure will make slowly southward progress into the area Monday night into Tuesday morning with clouds lingering across the area. Low temperatures on Tuesday morning will range from the upper 40s along the Highway 20 corridor to the mid 50s in far southeast Iowa, far northeast Missouri and adjacent area of Illinois. Ridging and near normal temperatures are expected to start the period. Discussion: H5 ridging builds into the area before a shrtwv moves into the central CONUS at the end of the weekend.
High pressure will build into the area in its wake. Warmth should return on Tuesday with a mix of sun and clouds, as ridging builds in aloft.
855 AM EDT Mon May 8 2023 High pressure over Hudson Bay will nose to the south into our forecast area today. any leftover showers over the Southern Tier will give way to clearing from the north as high pressure will settle over the Upper Great Lakes.
358 PM EDT Mon May 8 2023 The rest of the afternoon is expected to be quiet across southern Indiana and central Kentucky, but convection has already initiated over southern Missouri ahead of an approaching cold front. For the rest of the day, high pressure moving into the Lower Ohio Valley will help mostly sunny skies return by the afternoon, but CAA is expected to limit temperatures to the 70s throughout the CWA.
/29 (Now through Tuesday) A subtle upper ridge over the region strengthens somewhat overnight into Tuesday as a broad upper low evolves over Texas. In addition, will need to watch for heavy rain with convection this afternoon given the higher deep layer moisture content compared to the rest of the period.
During the early morning hours, model show possible convection from a cold front moving in from Tennessee that may bring some rain and storm chances for northern portions of our region. 7 inches will extend across the across the Highway 84 corridor. This regime is characterized by an upper ridge centered over the area. The flat nature of the ridge will help to advect high level moisture from a southeast Pacific source region.
843 AM PDT Mon May 8 2023 Slightly warmer today with mostly sunny skies by late this morning. Cooler on Tuesday as a compact, fast-moving storm system moves over Southern California through the middle of this week.
Temperatures for the afternoon will be in the 60s, though it will be cooler in the 50s along the immediate lakeshores. The wave will run into the confluent flow though and it will tend to get shunted to the south over time as it moves across the lower Great Lakes. On Tuesday expect skies to clear from the north as center of high pressure settles over the Great Lakes. A smidge cooler aloft, so highs most spots will stay in the lower to middle 60s. It will be cooler near Lake Ontario with gradient onshore northeast winds. Given clear skies, light winds and dry airmass, lows inland from the lakes will be in the lower to middle 30s.
1129 AM EDT Mon May 8 2023 High pressure over Hudson Bay will nose to the south into our forecast area this afternoon. any leftover showers over the Southern Tier will give way to clearing from the north as high pressure will settle over the Upper Great Lakes.
352 PM EDT Mon May 8 2023 (This evening through Tuesday) Much of the region is expected to remain positioned underneath a "dirty" upper ridge through the short term period. A weak surface cold front will push southward into the forecast area tomorrow, but model discrepancies still exist with respect to the timing of the front and how far south it will make it before stalling.
1220 PM CDT Mon May 8 2023 (Rest of Today) Surface analysis this morning shows high pressure is encompassing much of the Southeast US, with the ridge axis centered over central AL.
Through the day, a weak area of low pressure will swing a cold front southward through the CWA. However, CAMs have been consistently developing convection along and just south of the cold front near I-70 this afternoon, so my confidence is currently higher in the previously described environment being realized across this portion of the CWA, yielding supercellular structures. There is some weakness in the low-level hodograph among model soundings, which does not build confidence in tornadoes. Tomorrow, upper-level ridging will begin building into the Midwest as an area of high pressure settles into the region.
Warmer temperatures and mainly dry conditions are expected for the latter half of the week. SFC cold front extended from the SW corner of PA through Somerset County and then SE to the DC Area. Focus tonight shifts to an area of low pressure tracking toward PA along the stalled front. Will keep the highest PoPs across the srn half of the CWA, and broaden timing out to cover a longer period through most of the day Tues. Tuesday looks wet for the srn half to 2/3rds of the area as the wave rolls gradually thru, with the 7H/5H trough sliding only slowly across the state from N-S. We have expanded the high PoPs around to most of the CWA for Tuesday.
(Rest of Today) Surface analysis this morning shows high pressure is encompassing much of the Southeast US, with the ridge axis centered over central AL.
Convective initiation currently looks to be along the front generally near the Highway 54 corridor around 2-4 pm. As the activity moves south of Hwy 54 it will weaken as it runs into the more capped air mass and not with the low level shear flow across much of the area, but should be able to maintain themselves a little better east of Hwy 63. An upper level trough will move across the Plains today and a surface boundary will push south across the area this afternoon and evening. An upper level ridge will remain over the region through much of the week with warmer conditions as highs in the 80s occur each day.
Winds out of the south will stay in the 10-20 mph range overnight, keeping the lower levels well mixed lending to mild overnight lows in the mid 60s once again. Weak upper level ridging will set up across the West Central Texas area tomorrow. Upper level clouds across our southeastern zones will keep temperatures down there slightly cooler in the upper 80s with areas further north and west warming into the low to mid 90s once again.
1108 AM EDT Mon May 8 2023 Low pressure will be followed by a dry cold front passage today.
The energy with the MCV should be sheared to the south and east in the mean flow, and dry low-level flow on the south side of an area of high pressure centered over Hudson Bay continues to beat back the advance of lower clouds and showers. Overnight lows should average around 40 degrees to the lower 40s. Upper level ridging is in control for the most part through the period.
The small closed low continues moving into SW Oregon this morning and will slowly move into eastern Oregon through the day and linger overnight.
Temperatures will be cooler than recent days, with highs today and Tuesday mainly in the mid to upper 70s. Main question for the remainder of the day will be with the redevelopment of storms as the cold front pushes through the area. The showers and thunderstorms should be out of the the area before midnight at the latest, when a cold front is set to clear out the area. Depending on how long the precipitation and cloud deck persist over central and southeastern Illinois, the highs could be closer to lower-to-mid 70s rather than close to 80.
Undercut NBM guidance a tad to hedge towards cooler than expected highs.
17Z observations show an upper level pattern with winds out of the west southwest in response to an upper low over the Pacific coast. The CAMs once again vary in where the initiation starts but the highest confidence looks to be in our southeast zones where CAPE values will be ~ 3000 J/kg and 0-6 km bulk shear values increase to > 40 kts by the late afternoon.
205 PM CDT Mon May 8 2023 Much quieter and cooler day compared to yesterday, when a strong low pressure system brought along hot and humid air, which resulted in severe weather throughout the area. Temperatures are currently sitting in the mid 60s for some, with many reaching into the low 70s. Low pressure moves out and high pressure will move into the north. With a little more sun peaking out tomorrow, temperatures are expected to increase back into the low- mid 70s for most. Through midweek, we will be under the influence of weak upper ridging, with high pressure sliding through the north.
214 PM MDT Mon May 8 2023 Update at 3pm: Low pressure over central Montana will slide southeast along the nearly stationary front this afternoon with instability showers already intensifying into thunderstorms. Potential for heavy rain still on track for late in the week with the higher probabilities over southeast Montana.
General troughiness to our west will continue to eject bands of energy east towards the Central Plains, but timing and location of these waves is difficult to determine at this time as deterministic models are not in agreement.
1201 PM CDT Mon May 8 2023 (Today and tonight) A cold front is moving into northern Oklahoma early this morning which will probably move south a little farther before stalling out across northern and western Oklahoma. Low-level temperatures will be warmer in the southwest near the dryline, so the cap will effectively be weaker than farther north. The primary signal along the warm front will be farther south today, so storm chances are less likely than the past couple of days across our Texas zones and southwest Oklahoma, but it is still worth some low POPs near the dryline in our southwestern counties.
Potential for scattered showers over inland southeast Georgia this afternoon and evening as high pressure ridging form out of the east recedes to the south allowing for more moist flow to push in over the area from out of the west. High temperatures for today will be in the upper 80s over inland areas and in the lower to mid 80s along the coastline. Overnight low temperatures will drop down into the lower to mid 60s over inland areas and in the mid to upper 60s for areas closer to the shore.
As the low shifts north and east, expect the convection to decrease into the evening hours. An upper trough pushing into southern California on Tuesday will put the area under southwest flow aloft.
240 PM CDT Mon May 8 2023 Outflow from the overnight activity is a bit harder to pickout now on latest surface analysis, though the cold front is making some progress to the south. The latest visible satellite loop showing some agitated cu over southern Missouri, especially along the I-44 corridor, with the back edge of CU field along the I-70 corridor near the location of the cold front. Byrd Upper level ridge will remain over the region through mid week, while an upper level trough will move on shore and deepen over the western CONUS.
24-hour rain totals in the North Bay Vary from just under a tenth of an inch to just under a quarter inch, with Venado being the high amount at 0. An additional weak trough is progged to move through Tuesday as part of this more broad upper trough pattern centered over the Pacific Northwest. Guidance exhibits reasonable confidence that rain chances will be minimal from this second trough, being overall less dynamic and passing further to our south, leaving much of the Bay Area and Central Coast on the drier side.
142 PM EDT Mon May 8 2023 A cold front will arrive later tonight into Tuesday to bring a chance of showers and thunderstorms.
129 PM EDT Mon May 8 2023 Weak high pressure builds in from the northwest though tonight, A weak wave of low pressure passes to the south on Tuesday, followed by high pressure building in for the second half of the week.
High pressure builds back into the area tomorrow, with dry weather and seasonable temperatures returning through the end of the week. Forecast sounding show an abundant amount of dry air in the low levels, so will not be surprised to only see sprinkles or VIRGA instead of any measurable rainfall. Lows tomorrow night will be in the low to mid 30s in most areas and frost headlines will be possible where the growing season is currently active.
130 PM EDT Mon May 8 2023 A cold front will arrive later tonight into Tuesday to bring a chance of showers and thunderstorms.
Storms development is generally along the Highway 54 corridor right now, but will gradually shift south along with the front through the evening and into tonight. An upper level ridge will remain over the region through much of the week with warmer conditions as highs in the 80s occur each day.
Ongoing convection this evening will gradually wane in coverage by late tonight as instability wanes and a surface cold front approaches. Tuesday night will be pleasant and cool, with low temperatures falling into the lower to middle 50s.
A fairly zonal pattern with weak ridging is expected to amplify through the week, giving way to even stronger upper-level ridging across the area.
Drier and warmer conditions expected mid to late this week. The widespread cloudiness will keep temperatures around 9 to 18 deg F below early May climatology with Valley highs ranging from the low 60s around Redding to low 70s in the northern San Joaquin Valley. Upper-level ridge will begin to develop along the West Coast for the second half of the week, gradually amplifying day-to-day.
1212 PM EDT Mon May 8 2023 Weak high pressure builds in from the northwest though tonight, A weak wave of low pressure passes to the south on Tuesday, followed by high pressure building in for the second half of the week.
125 PM EDT Mon May 8 2023 A cold front will exit the coast this morning. High pressure will then build across the region through mid-week.
223 PM CDT Mon May 8 2023 TONIGHT: As of mid afternoon, an area of unstable cumulus and weak showers has developed in southeast SD and is tracking northeast, associated with a weak upper disturbance pivoting around the upper low to our north. As the day progresses, this dry air becomes less of a concern with 12z deterministic models favoring moistening via warm air advection and a warm front lifting widespread 50+ degree dew points in by the afternoon.
340 PM EDT Mon May 8 2023 A low pressure system will move east through the Ohio Valley tonight, bringing a chance for showers and thunderstorms. High pressure and a drier, somewhat cooler airmass will build into the region on Tuesday. A slightly cooler airmass will settle into the area with highs on Tuesday in the upper 60s to lower 70s and lows Tuesday night in the mid to upper 40s.
154 PM MDT Mon May 8 2023 Water vapor shows upper trof over the western CONUS with plenty of waves/upper lows embedded within the southwest flow aloft into the Northern Plains.
so went with a bit wider window for potential, but think the highest potential across the landbased zones given the pattern would be during the late morning into early evening respectively due to diurnal influences.
Showers and thunderstorms will increase in our CWA this afternoon as a Pacific upper low comes ashore on the southern Oregon coast midday today, then ENE-ward across Oregon tonight, and across central Idaho Tuesday morning. Forecast instability is not extreme, but 30-40 kt shear is enough for isolated rotating storms, and relatively low freezing levels are supportive of hail. PoPs are forecast to lower sharply toward morning as the upper low passes by.
147 PM PDT Mon May 8 2023 Slightly warmer today with mostly sunny skies across the region. Cooler on Tuesday as a compact, fast-moving storm system moves over Southern California through the middle of this week.
The composite outflow / weak cold front will remain draped NW to SE across the forecast area and remain a focus for additional storms Tuesday afternoon. Storm potential wanes Tuesday night with focus then turning to the weak upper low forecast to develop across south TX.
347 PM EDT Mon May 8 2023 Mostly sunny and dry today as high pressure is overhead. High pressure builds in from the NW today, bringing mostly sunny skies and dry conditions today. NNW flow will keep temps about 5 degrees cooler than yesterday, with highs in the low to mid 60s across much of the area and river valleys in the upper 60s. High pressure remains overhead Monday night, allowing temperatures to fall into the upper 30s to low 40s. Blended in some MAV and LAV guidance to help generate cooler temps across this area while keeping conditions warm across the northern counties. Northerly flow will advect in a cooler airmass, keeping temps lower even though there will be increased sunshine.
(Rest of today through Tuesday) Latest model solutions depict broad high pressure sprawling across the Western Atlantic gradually weakening during the next couple of days, but remaining mainly stationary. Pressure gradients will then decrease as the ridge weakens, with sfc winds decreasing to below 10 mph in general. The combination of persisting subsidence and lighter winds will allow for afternoon temperatures to climb into the low- mid 90s by Tuesday afternoon, warmest over the west coast.
Stalled upper low is starting to lessen in strength and the precipitation associated with it in the east is now diminishing. Tuesday starts with a weak ridge moving across the areas followed by unsettled and warming southwest flow. Look for warmer overnight lows in the mid to upper 40s.
A cold front crosses our region from the north by late Tuesday.
Heights will rise under a building ridge on Tuesday. High temperatures could be tricky due to modifying clouds and/or showers/thunderstorms when the ridge alone would indicate highs in the 70s.
The Florida Keys are in an area of weak anticyclonic flow, with a trough off the southeast over the Bahamas. This set up has led to light northeast to east flow along the island chain, allowing for the development of an extensive cloud line extending well to the west of the Lower Keys. Outside of the Lower Keys, skies are mostly sunny and temperatures in the mid to upper 80s. A low will move off of Nova Scotia in the coming days and drag an associated frontal boundary across the Mid-Atlantic, shoving the low level ridge in the central North Atlantic eastward.
Warmer temperatures and mainly dry conditions are expected for the mid to late week period. Thickening clouds will hold temperatures up tonight, with minimum readings likely to range from the mid 40s over the N Mtns, to the low 50s across the Lower Susq Valley. Latest guidance supports a brighter and warmer Tuesday afternoon than earlier forecast. Expect cloudy and showery conditions during the morning associated with wave of low pressure passing south of PA.
The wave will run into the confluent flow though and it will tend to get shunted to the south over time as it moves across the lower Great Lakes. On Tuesday expect skies to clear from the north as center of high pressure settles over the Great Lakes. A smidge cooler aloft, so highs most spots will stay in the lower to middle 60s. It will be cooler near Lake Ontario with gradient onshore northeast winds. Given clear skies, light winds and dry airmass, lows inland from the lakes will be in the lower to middle 30s.
HiRes guidance differs a bit regarding the evolution of the MCS, with some splitting our forecast area between a stronger surge to our west as well as to our east over the lower Appalachians. Overnight lows will be in the low to mid 60s with increasing clouds.
(This evening through Tuesday) Much of the region is expected to remain positioned underneath a "dirty" upper ridge through the short term period. A weak surface cold front will push southward into the forecast area tomorrow, but model discrepancies still exist with respect to the timing of the front and how far south it will make it before stalling.
On Tuesday expect skies to clear from the north as center of high pressure settles over the Great Lakes. A smidge cooler aloft, so highs most spots will stay in the lower to middle 60s. It will be cooler near Lake Ontario with gradient onshore northeast winds. Given clear skies, light winds and dry airmass, lows inland from the lakes will be in the lower to middle 30s.
A cold front will approach from the north late Tuesday afternoon and move through the region during the evening. Slightly cooler temperatures behind the front with dry conditions through late week. Pressure ridge across Florida, with resulting southwest to west flow transporting slightly higher moisture into the region compared to yesterday. Upper ridge across the Midwest and northwest flow continues across the Carolina and east central GA. Surface Pressure ridge to the south across FL. Upper trough to the north shifts to the Mid Atlantic and Carolina coast by evening. This will drive a weak cold front into the area from the north.
High pressure builds back into the area later Tuesday, with dry weather and seasonable temperatures returning through the end of the week. Forecast sounding show an abundant amount of dry air in the low levels, so will not be surprised to only see sprinkles or VIRGA instead of any measurable rainfall. Lows tomorrow night will be in the low to mid 30s in most areas and frost headlines will be possible where the growing season is currently active.
(Rest of Monday through Tuesday) A weak southwest to northeast cold front passed through the Bay Area Monday morning. Tuesday will be a similar day as Monday expect maybe another degree or two warmer. Another short wave pulse will wrap around the upper level low on Tuesday.
Continued the increase in pops but have the highest after 3 am.