Westmoreland County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Westmoreland County: 1.
2. Weak tornadoes were under-recorded before Doppler radar coverage became national in the early 1990s, so earlier decades read low. Ratings use the Fujita scale before February 2007 and the Enhanced Fujita scale after.

Storm Prediction Center severe weather database, 1950 to 2025.

Every storm within 100 miles

1. Tropical storms and hurricanes (34 kt or more, still tropical) at closest approach. Post-tropical remnants with gale-force winds are listed but not counted. Direct: track within 50 miles; near: within 100 miles. Distance is measured to the county boundary for counties and to the city centre for cities, using positions interpolated hourly between HURDAT2 fixes.

National Hurricane Center HURDAT2, 1851 to 2025.

Smoke overhead

1. A smoke day is a date on which a smoke plume traced by NOAA Hazard Mapping System analysts from satellite imagery covered this place's point (the county's population centre or the city centre). Counts here are of medium or heavy smoke. Since 2018 analysts have often drawn light smoke as one area over most of the continent, so light-smoke counts are not comparable from year to year. The plumes show smoke anywhere in the air above, not air quality at the ground, and smoke hidden by cloud is missed.

NOAA Hazard Mapping System smoke analysis, 2011 to 2026, retrieved October 30, 2026.

Claims by ZIP code

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026. NOAA Storm Events through 2026.

River crests

River gauges

1. Crests are the highest and the recent crests the National Weather Service lists for each river gauge in the county that has a flood stage, not every flood. Flood categories use each gauge's current flood stages; crests from before levees, dams or channel changes may not be comparable. Crests measured on an old datum are left out of the rankings.

NOAA National Water Prediction Service gauge records, retrieved October 30, 2026.

1. The Palmer Drought Severity Index is computed by NOAA each month from the county's average temperature and precipitation, relative to the county's own climate. Zero is normal; -3 or lower is severe drought and -4 or lower extreme drought. It describes the long-term balance of moisture, not water supply or crop losses.

NOAA NCEI nClimDiv county Palmer Drought Severity Index, 1895 to September 2026, issued October 6, 2026.

1. Earthquakes of magnitude 2.5 or more in the USGS Comprehensive Catalog since 1900. Within 50 miles means the epicentre lies within 50 miles of the county boundary (or inside the county).
2. Small earthquakes were under-recorded before the modern seismic networks of the 1970s and are still missed in remote areas, so early decades read low. Magnitudes are as the catalogue reports them and mix scales (moment, local and body-wave).

USGS ANSS Comprehensive Earthquake Catalog, 1900 to present, retrieved October 30, 2026.

Mapped landslides

Mapped by NASA (9), USGS Conterminous (1), USGS PA (Pomeroy, 1974) (1).

Deadly landslides

1. Landslides mapped in the USGS compilation of landslide inventories across the United States (version 3.0, 2025), rated probable or better. The compilation joins inventories made by federal and state agencies for different purposes and areas, so the number mapped in a county reflects how closely it has been surveyed as much as how often its slopes fail. An area with few records may simply not have been mapped. Deaths are as recorded in the inventories; a slide listed in two inventories is counted once.

USGS Landslide Inventories across the United States, version 3.0, retrieved October 27, 2026.

More event types since 1996

Costliest events since 1996

1. Jun 17, 2009Flash Flood$9.0 million
   National Weather Service narrative

   Emergency management reported widespread flash flooding across much of western amd central Westmorland county from Murrysville to Greensburg and Mount Pleasant. At least 1,192 buildings were affected, with 136 having major damage and 11 buildings destroyed. Damages were estimated to be around 9 million dollars. Most major roadways had flooding and some were closed well after the water receded to clear debris. The hardest hit areas from Murrysville to Greensburg had rainfall of over 4 inches in 3 hours.

2. Sep 17, 2004Flood, Westmoreland$5.0 million
   National Weather Service narrative

   By 3 PM EDT on 17th, 911 started receiving flood calls. By 353 PM, streams overflowed and flooded Vandergrift. 417 PM, Greensburg Rd closed by flood in New Kensington. 5 PM, Irwin had 2.5" of rain. 534 PM, roads flooded 1 mile southwest of Apollo. 548 PM, 1 house evacuated near a previously damaged dam in Allegheny Twp; and New Kensington 6" of rain. 606 PM, Freeport Rd flooded 1 mile south of Tarentum; people being evacuated. Roads closed, included Rte 30, 381, 982. Total of 819 homes and businesses, and 75 public structures damaged or destroyed. Ligonier sewage treatment plant damaged. Many basements were flooded by Youghiogheny River when Sutersville rose above flood stage (20…

3. Jan 19, 1996Flood, Westmoreland$4.0 million
   National Weather Service narrative

   On the Monongahela River near record flooding occurred at all Pennsylvania forecast points, except where record flooding occurred at Lock 2 Braddock. The crest at Lock 2 actually exceeded the crest during the flood of November 1985 by almost a foot. This was due to the tremendous contribution made by the Youghiogheny River during this particular flood. The crest at Braddock was 29.1 feet, 7.1 feet above its 22 foot flood stage, at 9 am on the 20th. Damage was extensive along the river.In Greene County, 9 homes, 3 businesses, and 3 trailer courts were affected.In Fayette County, 499 residences, 55 businesses, 4 churches, 1 fire department, 30 roads, 5 bridges, and 4 sewage plants…

4. Mar 23, 2011Tornado$4.0 million
   National Weather Service narrative

   The National Weather Service survey team confirmed a tornado in hempfield township in Westmoreland county. The tornado initially touched down in the Sewickley township area/Rillton section and then moved along route 136 in Hempfield township. There were numerous single family homes damaged in the Rillton area with some having homes having their entire rooves removed. In addition, one home lost an exterior wall. Numerous trees were uprooted in the area as well. Damage was then observed near the Hempfield bus garage with damage to multiple structures. Near this location was when the path width was the largest. Moving farther east, the Hempfield Senior Highschool scoreboard was…

5. Jun 1, 2012Tornado$3.0 million
   National Weather Service narrative

   The National Weather Service office in Pittsburgh Pennsylvania confirmed an EF1 tornado touched down near Ligonier in Westmoreland county on June 1st. The tornado initially touched down a quarter mile east of the Borough of Ligonier and traveled northeast causing sporadic damage over a path of approximately 5 miles before lifting east of the Champion Lakes golf course. ||The most intense damage occurred to a house on Robb Road, where the entire roof was blown off. The width of the tornado at this location was approximately 100 yards. Another mile or two north, along route 711 and Stanislaw Farms, 10-20 trees were snapped at the truck or uprooted. Three stationary vehicles were…

6. Jun 20, 2018Flash Flood$1.5 million
   National Weather Service narrative

   The 911 Call Center has reported numerous water rescues in Ligonier Township. The local Giant Eagle was surrounded by water and intersections on Route 30 were closed.

7. Nov 27, 2022Hail$1.2 million
   National Weather Service narrative

   Hail caused holes in siding along west side of a house, with dented cars also reported. Similar car damage to that seen in Fayette County was also likely, with possibly up to 400 cars damaged.

8. Jun 26, 2024Thunderstorm Wind$1.0 million
   National Weather Service narrative

   A well-organized upper shortwave trough crossing the western Great Lakes and Ohio River Valley and associated cold front crossed the region. Warm, moist conditions across the Ohio River Valley along with limited cloud coverage resulted in increasing instability (2000-3000 J/kg) over the course of the day. This along with increasing vertical wind shear up to 40kts (effective) as the trough and front approached from the west brought conditions favorable for severe weather by late afternoon / early evening. Damaging wind was the main threat with a notable mid-level dry layer, however, tornadoes were also possible.

9. Jun 30, 1998Thunderstorm Wind$1.0 million
   National Weather Service narrative

   Thunderstorm winds downed numerous trees and power lines. Major damage was reported to around ten homes, with numerous other homes in the area receiving minor damage. A new concrete block was at a car dealership was knocked over.

10. Jun 20, 2018Flash Flood$1.0 million
    National Weather Service narrative

    The county 911 Call Center reported residential flooding. Loyalhanna Creek is out of its banks. Many water rescues had to be performed; in some homes residents had to be rescued from their roof. The Loyalhanna Creek at Kingston, PA gage rose from 3ft to 11.7ft (crest) in roughly 10 hours.

1. Storm Events records before 1996 cover only tornadoes, thunderstorm wind and hail. Damage figures are as reported by the National Weather Service at the time, not adjusted for inflation.

NOAA NCEI Storm Events Database, 1950 to 2026, issued October 26, 2026.

All-time high

102°FJul 14, 1936

All-time low

−16°FJan 23, 1936

Warmest night

77°FAug 12, 2016

Coldest day

−2°FJan 23, 1936

Wettest day

6.00 inSep 17, 2004

Snowiest day

12.0 inNov 24, 1950

Hottest year

2024mean 56.6°F

Coldest year

2003mean 51.0°F

Wettest year

201866.71 in

Driest year

194629.24 in

Station Pittsburgh Allegheny County Airport (USW00014762), 1,244 ft elevation, 17.2 miles from the population centre. Daily records from 1935 to October 26, 2026; 91.8% of days in the last 30 years are complete. Records at a single station can differ from a city’s official threaded record, which may combine several stations.

NOAA NCEI Global Historical Climatology Network Daily.

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA Disaster Declarations Summaries, retrieved October 30, 2026. Statewide declarations are not listed.

Neighbouring counties

• Tornadoes NOAA Storm Prediction Center severe weather database, through 2025.
• Tropical cyclones NOAA National Hurricane Center HURDAT2 (Atlantic; Northeast and Central Pacific), through 2025.
• Wildfire USGS/USFS Monitoring Trends in Burn Severity, through 2026.
• Storm events NOAA NCEI Storm Events Database, through 2026.
• Flood insurance OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026.
• Declarations OpenFEMA Disaster Declarations Summaries v2, retrieved October 30, 2026.
• Weather records NOAA NCEI Global Historical Climatology Network Daily, station USW00014762.
• River crests NOAA National Weather Service, National Water Prediction Service river gauges, retrieved October 30, 2026.
• Drought NOAA NCEI nClimDiv county Palmer Drought Severity Index, through September 2026.
• Smoke NOAA NESDIS Hazard Mapping System smoke analysis, retrieved October 30, 2026.
• Landslides USGS Landslide Inventories across the United States, version 3.0 (2025).
• Earthquakes USGS ANSS Comprehensive Earthquake Catalog (ComCat), retrieved October 30, 2026.

Joins, thresholds and known limits are set out in the methodology. Found an error? Report it. Page built October 30, 2026.