Aikyam-Lab/Synoptic-Bench huggingface dataset:
Main concern in the forecast period will be storms associated with a cold front moving through the area this morning into early afternoon. Storms should exit the area by mid afternoon, with the cold front providing at least a little temporary, slight relief from the persistent heat of the past several days. Expect highs to range from the lower 80s in northeast Nebraska to the upper 80s as you move south of Interstate 80. Beyond today, we'll be back into another extended warm and generally dry period as upper level ridging builds back in over much of the CONUS.
1220 AM EDT Fri Jun 11 2021 Thunderstorms will increase in coverage over the next few days as a cold front drops in.
An upper level low resides across the region this morning with a very moist airmass in place. The upper level low continues to provide some weak ascent that has led to some heavy showers and storms overnight. With the upper level low virtually on top of us, storm movement has been very slow to almost stationary at times. The upper level low will shift eastward tonight with a weak trough axis shifting southward across the area. A weak cold front will accompany this, bringing a chance of showers/storms mainly in the afternoon and especially along the Virginia Border. To the west, a large ridge will sit across the Midwest keeping the upper level pattern very meridional.
NAM, GFS, and Canadian now are all bringing the low across SE MI during Saturday afternoon, 18-21Z timeframe. Timing of this low places it around peak heating and diurnal instability with forecast MLCAPE values between 1000-1500J/kg being more than enough to generate scattered thunderstorms. Relief from the heat and humidity will come next work week as a longwave trough develops over the eastern US/Canada.
738 AM EDT Fri Jun 11 2021 Low pressure forms and passes well to the south today and Saturday.
The pesky upper level trough that has brought the isolated to scattered showers and thunderstorms to much of central Indiana over the last few days will slowly continue to exit the area with a broad ridge building across the Central United States. Diurnally driven showers and storms are expected again today with the most widespread coverage across the southeastern counties where forcing associated with the low will provide additional lift in addition to the diurnally driven forcing. The more widespread rain and clouds across the southeast should keep highs from reaching much above the mid 80s with temperatures in the low 90s across the west where cloud cover will be less. A series of weak vort maxes will be rounding the ridge and providing some minor lift in addition to convective temperatures being reached.
1042 AM EDT Fri Jun 11 2021 Morning diurnal cu development on satellite and current obs show ridge axis of high pressure over the west Atlantic has shifted south of Lake Okeechobee, and will continue to migrate farther southward through the day. Ridge axis south of the waters will keep winds out of the S/SW around 10-15 knots this morning, becoming southeast near the coast as the sea breeze develops.
Cold front on the way Cold front expected to enter the GUY/DHT site with north winds around 15-20kts gusting up to 30kts after 13z.
538 AM EDT Fri Jun 11 2021 Warm and humid conditions under upper level low pressure should maintain showers and thunderstorm chances across the region today. A mid/upper level low should continue to drift east across the Upper Ohio Valley region today. The mid/upper low is progged to phase with a nrn stream trough tonight. Expect showers and thunderstorms to end from N-S as the trough completes its passage.
620 AM CDT Fri Jun 11 2021 (Today and tonight) Another very hot day in store across West Central Texas with temperatures likely a degree or two warmer than yesterday. Warm again tonight with lows only in the low to mid 70s.
447 AM CDT Fri Jun 11 2021 Hot and humid conditions with little chance for rain into the start of the weekend as an upper level high will be the main weather player.
Plenty of clouds and a few showers will persist tonight, before a second cold front drifts south from New York state on Saturday with another round of showers and a chance for a thunderstorm.
550 AM CDT Fri Jun 11 2021 Hot and humid weather will prevail across central Illinois today with afternoon high temperatures topping out in the lower 90s. 08z/3am water vapor imagery shows pronounced ridge axis extending from the Upper Midwest to the Southern Plains. while persistent trough that has triggered daily showers/storms across the KILX CWA has shifted well to the east into the Ohio River Valley. Other than that, am expecting a very warm and humid day across central Illinois with highs mostly in the lower 90s.
There is little to no shear present, low level or deep shear, lapse rates are weak, plus LCLs range around 1500m and so any threat would be wind with the high-based nature of the convection.
401 AM CDT Fri Jun 11 2021 The direct influence of the departing/weakening trof that has given the PAH forecast area a daily threat of rain for the last week or more will be seen once again this afternoon. This activity is expected to end quickly by early evening as the boundary layer cools, and ridging aloft begins to build into our region. Sat, weaknesses in the mid level ridge will continue to enable scattered shower and tstm development across the region in the afternoon, though parts of southeastern MO may be affected by possible MCS activity early in the day.
645 AM EDT Fri Jun 11 2021 A moist airmass combined with a low pressure system moving through the area will keep the threat for showers and thunderstorms in the Ohio Valley today. Mid level trof remains positioned over Southern Ohio. This low along with moderate instability will lead to increased shower and thunderstorm activity this afternoon. Highs temperatures to range from the mid 80s northwest to the lower 80s southeast. Low temperatures to range from the lower 60s northeast to the upper 60s southwest.
Scattered showers and storms have been more widespread tonight in comparison to the last couple of nights with the trough axis very close to the area. Today is finally moving day for the large upper trough. The trough axis will slowly work east of the area during the daylight hours. With dew points in the lower 70s and temperatures climbing to around 90, afternoon heat index values will approach the upper 90s tomorrow afternoon.
902 AM EDT Fri Jun 11 2021 Warm and humid conditions under upper level low pressure should maintain showers and thunderstorm chances across the region today. Expect showers and thunderstorms to end from N-S as the trough completes its passage.
Showers linger across the region with the cold air advection behind yesterdays cold front passage. As the system moves east and high pressure builds into the region, clearing skies and diminishing winds are expected by evening. Upper ridge will begin building north along the Rockies during the weekend.
329 AM MDT Fri Jun 11 2021 Across the Tri State area this morning, skies are mainly clear as a long awaited cold front begins its trek through the region. Temperatures are in the 70s ahead of the cold front, with 50s and 60s set to work into the region behind the front. High pressure building in behind the front will provide the area with a nice dry, yet windy day. The WAA at the surface will be aided by another strong ridge aloft at 500mb moving into the Plains region.
The higher valleys along the Continental Divide are already experiencing temperatures below freezing. The upper level flow pattern has become southwesterly after the passage of the trough of low pressure.
Strong upper low will remain just off the British Columbia coast through the weekend and keep an unseasonably strong trough southward over the eastern Pacific and along the West Coast.
Otherwise, look for highs in the low to mid 80s and dew point temps in the low to mid 70s to add a humid feel to the air. Northwest flow aloft behind the mid-level trough axis will push moisture from the Corn Belt into the TN Valley, and we will see dew points push uncomfortably into the mid 70s tomorrow during the day. Coupled with the high dew points, heat index values will top out in the upper 90s to potentially near triple digits.
516 AM MDT Fri Jun 11 2021 Across the Tri State area this morning, skies are mainly clear as a long awaited cold front begins its trek through the region. Temperatures are in the 70s ahead of the cold front, with 50s and 60s set to work into the region behind the front. High pressure building in behind the front will provide the area with a nice dry, yet windy day. The WAA at the surface will be aided by another strong ridge aloft at 500mb moving into the Plains region.
Much drier air mass filters into the forecast area, along with cooler temperatures, but given potential for deeper mixing in northwest post-frontal flow, have still hedged toward the warmer side of guidance for highs most areas. This generally yields highs in the 80s, or a good 10-15F cooler than yesterday, though still at/above normal for this time of year. Warmer low level air does begin to nudge back into the area, so highs will favor the higher end of the 80s.
The second concern is the potential for isolated strong to severe storms to redevelop along the cold front this afternoon and into the evening. CAMs show instability building ahead of the cold front through the early afternoon before initiation around 21Z. With that in mind I have nudged highs a degree or two warmer for the eastern half of the CWA with lower 90s in the Twin Cities. Temperatures and dew points finally drop behind the cold front. Overnight lows will cool into the 60s tonight with highs warming into the lower to mid 80s Saturday.
/issued 217 AM EDT Fri Jun 11 2021/ Pattern change will begin to take place today and tonight as a weak U/L trough sinks south over the Florida peninsula displacing the persistent U/L ridge.
It's going to be warmer today than yesterday, too, and this weekend is going to be even warmer than today. ML/UL trough will slowly move across the area.
A cold front dropped southward over the plains overnight, bringing cooler temperatures and gusty winds to 40-50 mph to that area, especially the far eastern plains. The plains and valleys will warm into the low/mid 80s and the mountains will warm into the 60s and 70s.
/issued 246 AM CDT Fri Jun 11 2021/ SHORT TERM (Now through Saturday): 500 mb high pressure centered over west Texas will remain the dominant force over the BRO CWFA during the period.
The direct influence of the departing/weakening trof that has given the PAH forecast area a daily threat of rain for the last week or more will be seen once again this afternoon. This activity is expected to end quickly by early evening as the boundary layer cools, and ridging aloft begins to build into our region. Sat, weaknesses in the mid level ridge will continue to enable scattered shower and tstm development across the region in the afternoon, though parts of southeastern MO may be affected by possible MCS activity early in the day.
The presence of the low stratus makes determining the extent of dense fog tricky, but a survey of webcams suggests a Dense Fog Advisory is not needed at this time. Scattered showers and even one thunderstorm are in progress in this area, and an isolated storm will continue to be possible early this morning given that the upper trough is directly overhead and the atmosphere is weakly unstable. The upper level trough continues to drift southeast today, on its way to the Appalachians tonight. Expect a warm and humid afternoon with highs in the low to mid 80s. Over the weekend, a large upper level ridge will begin to amplify over the Desert Southwest and Intermountain West while a trough digs into the eastern CONUS. Flow aloft will remain out of the north and northwest over the lower Ohio Valley.
646 AM EDT Fri Jun 11 2021 A moist airmass combined with a low pressure system moving through the area will keep the threat for showers and thunderstorms in the Ohio Valley today. Mid level trof remains positioned over Southern Ohio. This low along with moderate instability will lead to increased shower and thunderstorm activity this afternoon. Highs temperatures to range from the mid 80s northwest to the lower 80s southeast. Low temperatures to range from the lower 60s northeast to the upper 60s southwest.
/issued 447 AM CDT Fri Jun 11 2021/ Hot and humid conditions with little chance for rain into the start of the weekend as an upper level high will be the main weather player.
Broad scale ascent continues across the region beneath the upper trough, which should pivot through the region today/tonight. ABM Chattanooga Airport, TN 84 71 90 70 91 / 60 50 20 10 20 Knoxville McGhee Tyson Airport, TN 82 69 87 68 88 / 80 60 30 10 30 Oak Ridge, TN 82 69 87 67 89 / 80 60 20 10 30 Tri Cities Airport, TN 81 67 83 64 86 / 80 60 50 20 40 TN.
956 AM CDT Fri Jun 11 2021 Hot and humid weather will prevail across central Illinois today, with afternoon high temperatures topping out in the lower 90s. 08z/3am water vapor imagery shows pronounced ridge axis extending from the Upper Midwest to the Southern Plains. while persistent trough that has triggered daily showers/storms across the KILX CWA has shifted well to the east into the Ohio River Valley. Other than that, am expecting a very warm and humid day across central Illinois with highs mostly in the lower 90s.
551 AM EDT Fri Jun 11 2021 Low pressure forms and passes well to the south today and Saturday.
Scattered showers and thunderstorms will persist through the early morning hours as a 500 mb trough axis swings through the Southeast. Otherwise, persistent cloud cover and rainfall will keep temperatures slightly below daily normal values as we peak in the low to mid 80s this afternoon. Northwest flow aloft behind the mid-level trough axis will push moisture from the Corn Belt into the TN Valley, and we will see dew points push uncomfortably into the mid 70s tomorrow during the day. Coupled with the high dew points, heat index values will top out in the upper 90s to potentially near triple digits.
1104 AM CDT Fri Jun 11 2021 Wx map shows the seasonal Bermuda High pressure ridging across the SE U. /issued 447 AM CDT Fri Jun 11 2021/ Hot and humid conditions with little chance for rain into the start of the weekend as an upper level high will be the main weather player.
Surface analysis places center of low pressure over central Ohio with two notable troughs, one extending SW across central KY and another extending W across central Indiana. As the low moves farther east, ridging aloft builds in bringing drier air that should limit convection tomorrow afternoon. And with dew points in the low 70s, real- feel temperatures will be in the mid to upper 90s. So stay hydrated and seek shade! A ridge west/trof east upper height pattern will be the rule for the upcoming week.
Mid level ridging lies over North Central Mexico/West Texas with an inverted trough along the West Gulf. High pressure dominates the Gulf. Influence from upstream ridge could be a factor. /issued 246 AM CDT Fri Jun 11 2021/ SHORT TERM (Now through Saturday): 500 mb high pressure centered over west Texas will remain the dominant force over the BRO CWFA during the period.
Propagation vectors would favor the MCS tracking near this low level instability corridor through the evening with a continued risk of damaging winds. Further west the sfc cold front extends from NE KS through NW OK. Either the residual outflow and/or the synoptic cold front may remain across the forecast area to support low storm chances, otherwise a warm and humid day is likely. Strong ridge aloft amplifies and becomes centered over the Inter- mountain west through mid week. The prevailing northerly flow aloft through the central / eastern CONUS will allow several cold fronts to sweep southward and the local region will remain on the periphery of these airmass changes. Overall expect temperatures to remain warm however lower dewpoints are likely to also prevail with persistent sfc ridging along the Gulf Coast.
Forecast soundings overnight reveal continued moistening of the low-levels, and thus have elected to nudge PoPs upward slightly to the chance category (around 30%) for tonight, with most activity occurring well after midnight and around sunrise.
High temperatures across the area are expected to be in the low to mid 80s this afternoon, which is about a 15 degree drop from yesterday.
Associated warmer/drier conditions aloft will lead to a dry/hot remainder of the afternoon for most, though diurnal instability could be enough to develop an isolated storm near subtle outflow/lake boundaries late this afternoon. Fold over of a the low level thermal ridge with MLCAPE values pushing 1500-2000j/kg suggest a decent chances for convection in the vicinity of the boundary, and subsequent outflow boundaries by peak heating.
This trend should continue as drier air above H850 begins to mix down with increasing insolation, resulting in a mix of clouds and sun for the afternoon with temps climbing into the lower/possibly mid 90s across the region. Upper ridging centered over Nrn old MX/far W TX remains progged to expand E into the Lower MS Valley this afternoon, with increased subsidence resulting in dry conditions for a change areawide.
A strong mid/upper level high pressure system centered across W TX, remains in control of S TX weather and will continue through Saturday. The high pressure will maintain the hot and humid conditions with moisture trapped in the lowest levels. The high temperature combined with a humid environment may lead to afternoon heat indices ranging from 105 to 109 across portions of S TX Saturday afternoon.
As the upper low lifts from N of Minot into Manitoba the winds will continue to spread to the east and north bringing in drier dewpoints and more stable airmass for the weekend. There was a trend yesterday evening with more of the high resolution models showing the current storms continuing to move east, but the stronger storms diving more into South Dakota. The rest of the day will feature increasing west winds and much cooler temperatures.
1115 AM MDT Fri Jun 11 2021 Across the Tri State area this morning, skies are mainly clear as a long awaited cold front begins its trek through the region. Temperatures are in the 70s ahead of the cold front, with 50s and 60s set to work into the region behind the front. High pressure building in behind the front will provide the area with a nice dry, yet windy day. The WAA at the surface will be aided by another strong ridge aloft at 500mb moving into the Plains region.
Transitional period as the upper ridge over the Central Plains retrogrades into the Rocky Mountain west. This will allow for an upper trough to carve out across the eastern US.
Lows were lowered to the lower 50s, with upper 40s portions of the western Sandhills. Warmer temperatures will return Saturday as a southerly flow returns.
247 PM EDT Fri Jun 11 2021 A weak cold front will move south across the area through tonight. Mainly dry weather will return for Saturday as a weak area of high pressure moves back into the area.
Pleasant temperatures are in place this afternoon but a strong ridge will build across the Four Corners region through the weekend and will be the main weather feature for much of the western U.
411 PM EDT Fri Jun 11 2021 A weak cold front will move south across the area through tonight. Mainly dry weather will return for Saturday as a weak area of high pressure moves back into the area.
75 inches, with 850-700 MB Theta-E ridge arriving during peak heating 18-22z.
Saturday will be drier, but a second cold front may touch off a few showers or a thunderstorm during the afternoon.
Behind the upper level wave that brought the line of storms will be a building upper level ridge with decreasing winds at the surface. This will allow for drier air and cooler morning temperatures. High temperatures will be in the 80s as the upper level ridge continues to build bringing no chances for precipitation.
A new upper level low pressure system has taken up a position off the coast placing the forecast area under a southwest flow aloft. A surge of moisture associated with a decaying cold front is passing over the region today causing mostly cloudy conditions.
SHORT TERM (Now through Saturday Night): High pressure dominates over the Gulf. Mid level ridging lies over North Central Mexico/West Texas with an inverted trough along the West Gulf. This pattern will continue in the short term though the ridge may edge a bit more overhead. Influence from the upstream ridge could be a factor.
As a result wind gusts have been relatively low this afternoon thus far and temperatures are about 5-10 degrees cooler. Temperatures will cool efficiently tonight given the dry air and weaker flow, but warmer than this morning. The ridge starts to build over the region tomorrow causing a spike in the temperatures by a good 10 degrees.
Then we have a weak trough/boundary from SC WI to a weak low near KMSP. There will be a mid level wave coming through along with a surface/850 trough. The HRRR does linger some isolated to scattered convection on Saturday with some suggestion of an inverted trough feature in the area.
However, dewpoints are also holding in the lower to middle 70s, which is resulting in heat index values from 107 to 114 degrees. Saturday afternoon, storms are expected to form off of the higher terrain of northern New Mexico and move towards the area within the northwesterly flow aloft.
If storms remain organize enough, convective outflow winds and a weak cold front will bring some relief from the humidity to most areas by Saturday morning.
239 PM MDT Fri Jun 11 2021 Satellite imagery and 500 RAP analysis showed southwest flow over the High Plains this afternoon, with high pressure above central Mexico and upper ridging extending from Texas to the Upper Midwest. At the surface, high pressure prevailed across the region behind last night's cold front. For tonight, a closed low near North Dakota pushes northward into Canada, allowing the upper ridge to amplify over the Plains. This weekend, ridging continues to build along the Plains and Rockies as a large trough develops off the west coast.
241 PM EDT Fri Jun 11 2021 Showers and isolated storms south of the Pennslyvania Turnpike will end later this evening as supporting low pressure exits. Convection is being supported by converging flow along a stalled frontal boundary with low pressure drifting across WV. A longwave trough across much of the Eastern CONUS should result in shower/thunderstorm chances Mon and Tue.
Broad scale ascent continues across the region beneath the upper trough, which should pivot through the region today/tonight. CDG Chattanooga Airport, TN 70 91 70 91 70 / 60 20 10 20 0 Knoxville McGhee Tyson Airport, TN 69 87 68 88 68 / 60 30 10 30 0 Oak Ridge, TN 68 88 67 89 67 / 60 20 10 30 0 Tri Cities Airport, TN 67 83 64 86 64 / 70 40 20 40 10 TN.
Associated warmer/drier conditions aloft will lead to a dry/hot remainder of the afternoon for most, though diurnal instability could be enough to develop an isolated storm near subtle outflow/lake boundaries late this afternoon. Fold over of a the low level thermal ridge with MLCAPE values pushing 1500-2000j/kg suggest decent chances for convection in the vicinity of the boundary, and subsequent outflow boundaries by peak heating.
It's going to be warmer today than yesterday, too, and this weekend is going to be even warmer than today. Scattered showers and thunderstorms will continue today before the influence of a slow moving upper trough finally moves east tonight into Saturday.
Only caveat to overall evolution is the warmer temperature after which could limit westward development.
In most locations, a building high pressure system will suppress convection, but a piece of the Pacific Jet will help initiate showers over northwest Montana.
Saturday afternoon, storms are expected to form off of the higher terrain of northern New Mexico and move towards the area within the northwesterly flow aloft.