Aikyam-Lab/Synoptic-Bench huggingface dataset:
Quieter night ahead and a little cooler. Pattern Synopsis/Forecast: Nearly stationary positively tilted upper trough extends from south-central Canada down through the Plains. At the surface, a weakening wave of low pressure continues to migrate through SE Ontario along a sfc boundary that nearly bisects northern Lower Michigan NE-SW as of 17Z. Cooler temperatures tonight compared to last nights near tropical feel, with lows spanning the 50s. High Impact Weather Potential: Low for now Pattern Synopsis: Dominant ridging will continue to hold firm across the Pacific NW as positive-tilt troughing begins to lift into the Great Lakes by the middle of the week.
SHORT TERM (Now through Monday Night): Rain chances and cooler weather will move into the area through the short term. An inverted 500 mb trough and closed low will continue to gradually move westward over the region through Monday with rain chances increasing through the period. Temperatures tomorrow will be cooler, thanks to the increased cloud cover and potential for rain, with highs in the upper 80s east to low 90s west.
Monday will start to see more the of influence of the high pressure over the Pacific Northwest start to dominate. Reimer Hot air moves into the region by midweek but models are weakening the strength of the upper ridge with is bringing the hot weather.
Then moisture will increase across all of southern Arizona Monday through the work week resulting in scattered showers and thunderstorms and cooler afternoon temperatures. Morning upper air plot and water vapor imagery showed a weak upper trof over SW NM. For today, the above mentioned trof over SW NM will be the focus for isolated to scattered thunderstorms, mostly in SW NM, with our far eastern areas, or east of a Safford to Bisbee line, on western edge of activity.
High pressure across the region as easterly flow continues. A weak Gulf breeze may try to develop as well, with enough diurnal heating temps into the low 90s. As we move into Monday, High pressure continues with easterly flow across the area. A mid to upper level low north of the region will continue to keep some mid-level dry air across S.
121 PM EDT Sun Jun 27 2021 The area will remain in warm, humid air for the next few days on the western periphery of Atlantic High Pressure.
127 PM EDT Sun Jun 27 2021 Aviation - Marginal risk for severe weather this afternoon - Potential for more heavy rain especially Mon Aftn-Tue A cold front is situated from Northern Lake Michigan southwest into portions of Northern Illinois. Dew points ahead of the cold front remain in the upper 60s to lower 70s. The low level jet remains quite stout at midday on the order of 35-40 knots at this point, but it should continue to diminish as we move through the afternoon and evening. However the low level jet is centered off to the east of the CWA and our area is generally in the divergent part of that feature.
The Upper Ohio River Valley is under the influence of a rain-suppressing high-amplitude ridge over the ern CONUS with split-flow troughing over the Midwest. Trough/cold front encroach wl spawn likely POPs for the midweek period and bring an end to the above-average warmth. Continued upper troughing is likely to spawn showery and cooler weather for the Independence Day weekend.
Heat will continue to increase over next few days, and reach dangerous levels, as the upper level ridge to our north and west slowly drifts east. Increasing easterly winds add to the heat with downslope warming coming off the higher terrain to the north and east.
Focus then shifts to potential impacts from a small low pressure system that has developed in the Atlantic 500 miles west of the Georgia waters. Slow intensification to a tropical depression or tropical storm is possible with the low moving through a low shear environment and then over the warm Gulf stream waters on Monday. Strongest winds and convection with this low are focused on the north side of the system keeping the higher impacts to our north at this time.
At this time the flash flood threat for Monday looks very isolated, but needs to be monitored for a flash flood watch, especially across southeast areas, given the synoptic scale lift from the mid/upper low coupled with the very deep moisture that is in place.
340 PM EDT Sun Jun 27 2021 High pressure will remain centered off the Mid-Atlantic coast through midweek. Aloft, an upper-level ridge off the Delmarva/lower mid-Atlantic coast continues to slowly retrograde or build westward across the lower mid-Atlantic coast. west of a Danville- Farmville-Ashland line early this afternoon, embedded in moist llvl airmass along a weak piedmont trough. Will need to watch weak area of low pressure along the Carolina coast.
The greatest instability of MLCAPE of 1500 to 2000 J/kg is instead located to the south of the trough; however, there is some overlap of shear and instability along the trough axis. Overnight, the prefrontal trough is forecast to lift northward and merge with a stationary front just to its north near the MO-IA border and IA-IL border.
139 PM PDT Sun Jun 27 2021 Strong high pressure will continue hot weather this week, particularly for the northern half of the Sacramento Valley and surrounding terrain. High pressure will continue to be centered over the Pacific Northwest with an area of low pressure off the coast.
A recent surface shows the primary stationary front draped from the Oklahoma Panhandle through the lower portion of Lake Michigan, with a warm front just to the south and east.
Otherwise temperatures tonight will fall back into the lower to mid 50s. The upper level pattern across the CONUS is characterized by an anomalously strong upper ridge anchored over the Pac NW and a trough that extends northeast across the central plains to near Hudson Bay. Mostly cloudy skies and the influence of the trough will lead to highs once again in the middle to upper 70s on Monday. The highly anomalous upper ridge over the Pac NW will slowly transition eastward toward the northern plains mid-week and weaken. The various solutions and ensembles then develop a closed low that centers over the Great Lakes by the end of the week.
319 PM EDT Sun Jun 27 2021 Sfc temps now in the low 80s with dewpoints from the upper 60s to near 70 is supporting 100mb ML CAPE around 1000 J/kg. A limiting factor for more widespread organized convection Monday looks to the be the fact that the mid level ridge will expand into the Upper Ohio Valley, leading to mid level height rises and potential capping across Se Mi.
245 PM CDT Sun Jun 27 2021 The area looks to remain under the influence of cyclonic flow aloft as troughing persists. For Monday, the trough axis hangs well northwest with bits of upper level energy proceeding it across southeast MN/northwest WI.
A deep layer southeasterly flow continues across our forecast area early this afternoon on the southwestern periphery of a ridge of high pressure nosing southwestward from the Eastern Seaboard/Appalachian Mountains through northern portions of MS/AL/GA.
Cooler and less humid conditions return by the end of the week, but mainly afternoon showers will still be possible. 8 to 2 inches and there is good instability with MLCAPE 500 to over 1000 J/kg, with the highest values to the southwest.
415 PM EDT Sun Jun 27 2021 Upper air pattern consists of a 500 mb ridge in the western U. and on the east coast with a deep trough over the central U. Upper level ridge pattern will persist over the Pacific Northwest and over the New England coast to start off the medium range forecast. Between the two upper level ridges, will exist an elongated longwave trough stretching from the James Bay to the southwest toward the central Plains.
258 PM EDT Sun Jun 27 2021 High pressure will remain centered off the Mid-Atlantic coast through midweek. Aloft, a retrograding upper-level ridge off the Delmarva/lower mid-Atlantic coast. Have noted a few (isolated) light showers/sprinkles west of a Danville-Farmville-Ashland line early this afternoon, embedded in moist llvl airmass along a weak piedmont trough. Will need to watch weak area of low pressure along the Carolina coast.
Temperatures will be cooler during the next 24 hours.
First of all, the winds, especially in the lower levels, remain very light.
A trough remains over the Tri-State area today with northerly flow over the Nebraska Panhandle. High pressure remains over the PAC NW with a ridge firmly in place over British Columbia. This pattern will change little over the next few days resulting in some cooler temperatures persisting through the Tri-State area and isolated chances for showers and storms. Highs today and tomorrow will range from the low 70s in Eastern Colorado to mid-80s in the eastern part of the Tri-State area. At the start of the period, high pressure dominates the west coast as well as southern and eastern portions of the CONUS. An upper trough can be seen over eastern Canada, extending southwest towards the Great Lakes.
Temperatures tonight cool off into the low to mid 70s. Temperatures typical for summer, warming into the upper 80s and 90s with overnight lows in the low to mid 70s. A low pressure system sits off the mid California coast blocked by an intense high pressure system that is sitting over the Pacific Northwest and into Southwestern Canada giving them record breaking temperatures and heat indices. In the northeast a low pressure system above the Great Lakes into Canada and a building Bermuda high over the southeast will keep the Mid-South in the summertime diurnal showers until these aforementioned systems begin to move.
345 PM EDT Sun Jun 27 2021 Low pressure over the Atlantic will drift towards the Southeast coast tonight into Monday, then move onshore across South Carolina or Georgia Monday evening. Atlantic high pressure will then generally prevail through late week. Weak low pressure over the Atlantic will drift westward towards the Southeast coast on Monday, then likely move onshore SC or GA Monday evening. NHC currently indicates a 50% chance of tropical cyclone formation. The highest rainfall totals are focused across southeast Georgia, with averages between 0.
Kuroski (Issued 300 PM CDT Sun Jun 27 2021) Tonight through Monday night: The cold front that moved through earlier today will sink south of Lake Michigan this evening. Relative high pressure over the lake, a slack pressure gradient and light winds will allow for some semblance of a lake breeze in the early evening, mainly between the 6pm to 8pm hours. This will lead to some cooler temps in the low 60s to upper 50s during the early evening for areas along and around the lakeshore primarily in southeast Wisconsin, while areas inland will linger around 70 and the upper 60s well after sunset. Overnight, The cold front will stall over the eastern corn belt and a weak area of low pressure will slide northeastward along the baroclinic zone from Oklahoma to the Middle Mississippi Valley Region.
Moisture will increase across all of southern Arizona Monday through the work week resulting in scattered showers and thunderstorms and cooler afternoon temperatures. The activity across SW NM this afternoon is associated with an upper level trof stretch NE to SW across NM.
Concur with deterministic output that an upper level low/trough to will approach/move westward across the CWA tonight/Monday, along with the development of a surface reflection/coastal trough.
Additional convection expected to form later as the boundaries lift northward, with the higher rain chances shifting into the northern CWA which has mostly stayed dry thus far. An omega block remains in place over the western CONUS with a large trough/southwest flow positioned over the Midwest states. SPC mesoanalysis as of 3 PM depicts MLCAPE of 1500+ J/kg across a good chunk of the CWA, though values quickly drop off closer to the aforementioned quasi-stationary cold front where a CAP is in place. The best shear is located across our northwest counties and points north/west of there, nearest to the upper trough.
800 PM MDT Sun Jun 27 2021 Isolated to scattered showers and a few thunderstorms are expected each of the next couple of days along with cooler than average temperatures.
650 PM CDT Sun Jun 27 2021 The area looks to remain under the influence of cyclonic flow aloft as troughing persists. For Monday, the trough axis hangs well northwest with bits of upper level energy proceeding it across southeast MN/northwest WI.
Did notice temperature trends in the southern valley were running a little cool, thus blended in the latest (warmer) NBM/ConsShort through mid/late morning to adjust trends upward for these areas, no changes elsewhere. With high pressure to the east, deeper flow will be more easterly on Monday, generally 4-8kts. CDG Chattanooga Airport, TN 71 91 71 88 71 / 20 20 10 50 20 Knoxville McGhee Tyson Airport, TN 69 91 69 89 70 / 20 30 10 30 20 Oak Ridge, TN 70 91 70 90 70 / 10 30 10 30 20 Tri Cities Airport, TN 66 92 65 89 66 / 20 30 10 20 10.
Temperatures overnight will drop into the low 70s. Upper level heights will also be slightly higher as the ridge across the Mid-Atlantic tries to expand southwestward.
Guidance is showing shower activity with embedded tstms becoming focused over the eastern plains overnight into early Monday morning as an upper low takes shape over southwestern NM. The monsoon is underway and here to stay with a trough axis over NM and a weak upper low over southwest NM. A large dome of high pressure way to our east will build west into TX midweek, turning our flow aloft to the south.
The regional infrared satellite imagery depicts an upper level low over the western Gulf of Mexico causing a large area of cloudiness. Temperatures in the island communities are in the lower 80s and the dew points are in the mid 70s. From synopsis, high pressure centered over the western North Atlantic will maintain moderate east to southeast breezes over the next few days.
Sfc temps now in the low 80s with dewpoints from the upper 60s to near 70 is supporting 100mb ML CAPE around 1000 J/kg. A limiting factor for more widespread organized convection Monday looks to the be the fact that the mid level ridge will expand into the Upper Ohio Valley, leading to mid level height rises and potential capping across Se Mi.
I expect that the band of convection ahead of the cold front is currently in Jackson County but should be out of the area by 9 pm. It would seem there is enough clearing of the lower clouds that we may see some fog toward morning so I added that to our forecast.
Cooler and less humid conditions return by the end of the week, with mainly afternoon showers possible at times. 8 to 2 inches and there is good instability with MLCAPE 500 to over 1000 J/kg, with the highest values to the southwest.
The heat will began tomorrow as the upper level ridge moves over the the Northern Rockies.
516 PM EDT Sun Jun 27 2021 Low pressure over the Atlantic will drift towards the Southeast coast tonight into Monday, then move onshore across South Carolina or Georgia Monday evening. Atlantic high pressure will then generally prevail through late week. Weak low pressure over the Atlantic will drift westward towards the Southeast coast on Monday, then likely move onshore SC or GA Monday evening. NHC currently indicates a 50% chance of tropical cyclone formation. The highest rainfall totals are focused across southeast Georgia, with averages between 0.
Temperatures will slowly fall overnight into the low 70s with dew points also in the low 70s, maintaining uncomfortably muggy conditions.
808 PM EDT Sun Jun 27 2021 Upper air pattern consists of a 500 mb ridge in the western U. and on the east coast with a deep trough over the central U. Upper level ridge pattern will persist over the Pacific Northwest and over the New England coast to start off the medium range forecast. Between the two upper level ridges, will exist an elongated longwave trough stretching from the James Bay to the southwest toward the central Plains.
753 PM EDT Sun Jun 27 2021 High pressure will remain centered off the Mid-Atlantic coast through midweek. Aloft, an upper-level ridge off the Delmarva/lower mid-Atlantic coast continues to slowly retrograde or build westward across the lower mid-Atlantic coast. Temps as of 730 PM generally in the low to mid 80s. Will need to watch weak area of low pressure along the Carolina coast.
Isolated to scattered showers will redevelop with the highest coverage in the afternoon. The first is the leading edge of the tropical moisture, ahead of the upper level low across the northwest Gulf of Mexico, that has arrived into the region. The upper level low across the northwest Gulf of Mexico will continue west and inland tonight into South and Deep South Texas, then open into an inverted trough along the Rio Grande.
Given the high-based nature due to a still dry boundary layer, strong gusty outflow winds and brief period of moderate to heavy rainfall will be the main threats from this activity.
A cold front will move through the region late in the week. Another warm/muggy night is in store with lows in the lower/mid 70s by daybreak.
/issued 305 PM CDT Sun Jun 27 2021/ SHORT TERM (Now through Monday Night): Rain chances and cooler weather will move into the area through the short term. An inverted 500 mb trough and closed low will continue to gradually move westward over the region through Monday with rain chances increasing through the period. Temperatures tomorrow will be cooler, thanks to the increased cloud cover and potential for rain, with highs in the upper 80s east to low 90s west.
With that being said, a few moderate to strong storms did develop south of Tampa Bay with the highest coverage near Charlotte Harbor. Slightly higher rain chances expected on Monday with the highest coverage south of Tampa Bay once again. The National Hurricane Center is keeping an eye on an area of low pressure northeast of the Bahamas. High pressure will be in place across the waters through the period.
Cooler than normal temperatures are expected again today and likely again on Tuesday. The southern portion of the upper level trough weakens and retrogrades back into the central Rockies while the northern portion moves into the Great Lakes region. Subtropical high pressure over the mid Atlantic and southeast states will build farther west into the southern Plains.
Mesoanalysis data indicated a pos tilted trof extending over the Cntrl CONUS, caught b/w two upper high pressure systems over each coastline. At the sfc, Srly flow on the Wrn periphery of Appalachian/SErn US high pressure has kept a persistent stream of >70F Td's across the state. Through the remainder of the PD, guidance suggests the Ern upper ridge wl begin to retrograde to the W, w/ any remaining troughing over the Cntrl US getting pushed N/wrd into Canada.
First of all, the winds, especially in the lower levels, remain very light. The elongated upper trough axis starts to move through the forecast area late on Tuesday which will keep the chance for showers and precipitation going with slight PoPs in the west and PoPs increasing to likely in the east. As the trough axis moves so will the chance for precipitation with showers and thunderstorms ending in the evening.
Aiding the increase precipitation potential is the cold front that has reached portions of far west Texas is now very slow retreating north as a warm front.
Afternoon highs will be in the 80s over the next several days with lows in the lower 70s.
351 AM EDT Mon Jun 28 2021 High pressure aloft will put a lid on today's afternoon thunderstorms. A few spots across south central GA should see temperatures in the low 90s. Strong upper level winds and a highly sheered environment have prevented further intensification, despite the center of the low's positioning above the warm waters of the gulf stream. Under ridging aloft. Still expect increasing diurnal summertime activity each day, with moisture really enhancing over the area late week and into the weekend as a deep trough develops over the Great Lakes and a frontal boundary and associated enhanced moisture axis sinks into the Tennessee Valley.
A cold front will move through the region late in the week. Another warm/muggy night is in store with lows in the lower/mid 70s by daybreak. A mid level ridge centered just off the mid Atlantic coast will continue to extend west into the Ohio Valley on Tuesday. Despite this ridge axis, ample moisture will be in place, and with no discernible capping inversion, scattered showers and thunderstorms are expected to develop by the afternoon hours. It will be very warm with highs in the upper 80s to the lower 90s. The combination of heat and humidity will result in heat index values in the lower to mid 90s. It will be warm and muggy once again with lows mainly in the lower 70s.
Did notice temperature trends in the southern valley were running a little cool, thus blended in the latest (warmer) NBM/ConsShort through mid/late morning to adjust trends upward for these areas, no changes elsewhere. Chattanooga Airport, TN 91 71 88 71 89 / 20 10 50 20 50 Knoxville McGhee Tyson Airport, TN 91 69 89 70 89 / 30 20 30 20 60 Oak Ridge, TN 91 70 90 70 88 / 20 20 30 20 60 Tri Cities Airport, TN 92 65 89 66 88 / 30 10 20 10 60.
The trough to the east combined with the ridge to the northwest will continue the northeasterly flow across Wyoming initially.
The region remains sandwiched between mid-level troughing over the Upper Midwest and a stout ridge located off the Mid-Atlantic coast.
There will be a decrease in any shower/thunderstorm activity later in the evening as the heating of the day is lost, though cannot rule out a few isolated showers overnight with an upper level trough axis remaining just to our west. Not much change for Monday with the upper level trough continuing to exert influence on our area. Highs will generally run in the lower 80s. By Tuesday the upper level trough axis begins to break down and slide eastward. We still could see a few showers/isolated thunderstorms during the day - more focused in our eastern CWA - as the main trough axis slides through the area. Temperatures will be similar to Monday - in the lower to mid 80s.
Ridging with heights and temperature 2-3 standard deviations above normal will result in another hot and humid day across the region. Trough/cold front encroach wl spawn likely POPs later in the week and bring an end to the above-average warmth. Continued upper troughing is likely to spawn showery and cooler weather for the Independence Day weekend. The confidence in thunderstorms is low due to mid- level ridging suppressing deep updrafts.
The only thing limiting coverage is a ridge of high pressure aloft extending over the area. Lows should fall into the low/mid 70s for most.
An upper level jet on the downwind side of an upper trough axis will continue to provide a broad area of upper level divergence overhead. However, we will begin to undergo rising heights overhead as an upper ridge over the eastern CONUS expands from east to west.
Main weather highlights through the near term will be influenced by a weak tropical wave and upper level low that is expected to move on shore the eastern US coast this afternoon. However, pinning down the best locations for rain is tricky as increased cloud cover from the upper level low will limit how much instability will develop in locations.
Early afternoon satellite/upper air analyses depicted a omega block pattern with a stationary upper ridge from British Columbia Canada into the Great Basin, and upper trough over the Great Plains. Short- wave energy embedded within the northerly flow aloft on the backside of the trough, combined with adequate instability (SBCAPE 500-1000 j/kg) and weak 0-6km shear triggered scattered thunderstorms over much of the CWA. Early this week, the omega pattern will begin to slowly break down, allowing the Great Plains trough to gradually translate east. The upper ridge to the west will weaken somewhat.