A portion of Westmoreland county in Pennsylvania was added to the Severe Drought (D2) areas of the Drought Monitor on July 30th. Conditions have gradually deteriorated through the region, with Severe Drought continuing into September.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PBZ wrote it up.
A portion of Westmoreland county in Pennsylvania was added to the Severe Drought (D2) areas of the Drought Monitor on July 30th. Conditions have gradually deteriorated through the region, with Severe Drought continuing into September.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Pittsburgh, PA wrote its last area forecast discussion before the first event at Jul 30, 3:41 AM EST, 3 hours 19 minutes earlier.
Area Forecast Discussion National Weather Service Pittsburgh PA 441 AM EDT Tue Jul 30 2024 .SYNOPSIS... A series of upper level disturbances may lead to periodic shower and thunderstorm chances through Saturday. Confidence is low on a flash flood or severe threat developing on a given day, though probabilities are higher Wednesday and Thursday. && .NEAR TERM /THROUGH TONIGHT/... KEY MESSAGES: - Shortwave progression east will generate scattered to numerous storms through this evening. - The main threats will be cloud to ground lightning and localized flash flooding. ------------------------------------------------------------------- Shortwave movement within the broader NW flow along the eastern side of the central CONUS ridge will cross the upper Ohio River Valley region through this evening. While a early morning MCS should track S/E of the region, the developing MCV plus upper shortwave will foster storm initiation that will traverse east in roughly two waves: a morning wave and late afternoon/evening wave. Limited diurnal heating as a result of morning convection plus area cloud cover should keep mean SBCAPE values below 1000 J/kg. This combined with weak shear should mitigate severe concerns. The focus then will be on potential for flash flooding due to PWAT values rising above the 90th percentile and weak storm motion. However, weak lapse rates and dry surface conditions are likely to keep flooding probabilities low and mainly tied to urban areas or locations receiving multiple rounds of rain. Subsidence on the backside of the shortwave and loss of diurnal heating is expected to reduce precipitation chances late tonight. Morning fog may develop depending on timing of cloud erosion, degree of decoupling and how saturated grounds become from rain. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... KEY MESSAGES: - Active weather pattern continues with periodic shower and thunderstorm chances. - Little airmass change will maintain low probability flood threats. - Conditional low probability severe threats will be highly dependent on upstream convective evolution. ------------------------------------------------------------------- The broad synoptic pattern will feature additional shortwave movement within the northwest flow overhead as broad upper ridging persists across the Southern Plains. Ensembles favor a more muted/weaker shortwave potentially crossing the Upper Ohio River Valley Wednesday while Thursday features a more well- defined upper trough approaching the region. Generally, this pattern will favor periodic thunderstorm chances with slightly above normal temperature for both Wednesday and Thursday. The details are much more varied with initiation and storm environment variables dependent on upstream convective evolution. Ensemble spreads suggest a notable range in storm timing/location plus shortwave positioning that could result in anything from prolonged periods of storms to little/no activity (where activity mainly progresses S/W of region). Assuming convective occurrence, current ensemble mean SBCAPE values show between 1000-1500 J/kg on Wednesday and 1500-2000 J/kg on Thursday with each exhibiting large spreads on low/high- end potentials. Maximization of these values will be key on severe threat potential (likely in the form of damaging wind with dry air present aloft) as mean ensemble shear is weak which would make storm organization difficult. Any thunderstorm could also generate heavy rainfall that leads to localized flash flooding, but dry antecedent conditions and weak surface convergence makes probability of occurrence low. && .LONG TERM /FRIDAY THROUGH MONDAY/... KEY MESSAGES: - Slow upper trough progression will maintain periodic storm chances and low probability flood/severe threats. - Northwest flow after the trough will support additional rounds of periodic thunderstorms. ------------------------------------------------------------------- Ensembles favor the slow progression of the more well-defined trough, with it approaching the area starting Thursday and finally shifting east of the region by Sunday. Finer-scale details remain uncertain but ensembles suggest minimal environmental changes beyond a slight uptick in area cloud cover and moisture resulting in greater precipitation chances and more seasonable temperature. Surface ridging and weak subsidence aloft behind the exiting trough suggests dry conditions are likely Sunday as temperature climbs a few degrees above the daily average. Dry conditions may be short-lived as the region will then remain positioned underneath northwest flow while ridging persists across the Rockies. This pattern would favor above normal temperature and periodic thunderstorm chances fueled by weak shortwave movement. && .AVIATION /09Z TUESDAY THROUGH SATURDAY/... MVFR cigs are expected to develop by mid-morning with scattered showers as low pressure crosses across the southern Great Lakes and low level moisture increases. Cigs should lift to VFR by early afternoon, but additional showers and thunderstorms are expected starting mid afternoon with increasing instability and a crossing shortwave. Main impacts should be very brief visibility restriction from downpours. .Outlook... Periodic restrictions are expected with scattered showers and thunderstorms through the week through with a series of low pressure troughs. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && SYNOPSIS...Frazier NEAR TERM...Frazier SHORT TERM...Frazier LONG TERM...Frazier AVIATION...88
Hazardous Weather Outlook National Weather Service Pittsburgh PA 318 AM EDT Tue Jul 30 2024 OHZ039>041-048>050-057>059-068-069-PAZ007>009-013>016-020>022-029- 031-073>078-WVZ001>004-012-021-509>514-310730- Tuscarawas-Carroll-Columbiana-Coshocton-Harrison-Jefferson OH- Muskingum-Guernsey-Belmont-Noble-Monroe-Mercer-Venango-Forest- Lawrence-Butler-Clarion-Jefferson PA-Beaver-Allegheny-Armstrong- Washington-Greene-Westmoreland-Higher Elevations of Westmoreland- Fayette-Higher Elevations of Fayette-Indiana- Higher Elevations of Indiana-Hancock-Brooke-Ohio-Marshall-Wetzel- Marion-Monongalia- Ridges of Eastern Monongalia and Northwestern Preston-Preston- Eastern Preston-Western Tucker-Eastern Tucker- 318 AM EDT Tue Jul 30 2024 This Hazardous Weather Outlook is for east central Ohio, western Pennsylvania, and northern West Virginia. .DAY ONE...Today and tonight. Scattered showers and thunderstorms could produce heavy rainfall that creates localized flooding concerns, favoring low lying or urbanized areas. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Periodic shower and thunderstorm chances through Saturday pose a limited flash flood threat, with concerns increasing if locations see multiple rounds of heavy rain. There is also a low probability severe threat with potential thunderstorms Wednesday and Thursday, conditional in part to the prior day's storm evolution. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
The national radar mosaic for the moment the first event began.
1 drought. Local standard time, as filed.
Severe Drought was added to the county on July 30th and has continued through the end of September at this point.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2024Every state in 2024This day in weather historyWarnings in Pennsylvania, July 2024
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1206899.