EF0 tornado, Buffalo to Gastonville, Pennsylvania, May 21, 2025

1. EF065 to 85 mphthis tornado

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

EF0

Date

May 21, 2025

Touchdown

4:47 PM EDT (20:47 UTC)

Lifted

4:50 PM EDT (20:50 UTC)

On the ground

3 minutes

Path length

2.2 miles (3.6 km)

Path width

75 yards (69 m)

Deaths

0

Injuries

0

Property damage

$10,000

County

Washington County

Touchdown point

40.250, -80.380

Lift-off point

40.240, -80.340

Record number

2505211447-01

47 damage points were recorded along this path by NWS PBZ, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 90 mph.

• Public shared pictures of tree damage at this location on social media
• Damage caused by non-tornadic wind in the gradient of the strengthening tornadic mesovortex
• Shingles and ridge covering removed from some homes is consistent with tree damage noted in the area (snapped hardwoods, uprooted softwoods)
• Uprooted softwood trees also in this area consistent with this wind speed

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

An occluding surface low slowly drifted across Ohio on May 21st. Bands of showers with embedded thunderstorms moved across southwest Pennsylvania. During the mid to late afternoon, one convective band, associated with ample 0-3km CAPE and surface vorticity, was able to generate four tornadoes across southwest PA. Three were relatively brief and weak, but one longer-track EF1 was noted in Washington County. Multiple rounds of slow-moving heavier rain also produced a number of flash flooding incidents.

Based on damage reports provided to NWS, a brief EF0 tornado (max wind 65 mph) began just east of Cross Creek County Park near Oakleaf Rd, crossed Willow Rd and likely weakened toward Lynn Portal Rd. Damage in this area was mainly to trees, where several large limbs were snapped and fascia was removed on a home along Willow Rd. This brief tornado preceded the longer-track one that began near Houston.

A tornado produced sporadic damage along a 14.5 mile path beginning near Houston, PA and finally dissipating 24 minutes later in Finleyville, PA. The initial damage occurred near Allison Hollow Road, where large limbs were broken from hardwood trees. The tornado continued east, uprooting trees along Irwin Avenue before crossing Locust Avenue and Walnut Street in Houston, where large hardwoods were snapped and softwoods were uprooted. Shingles were removed from several homes, a lamppost was bent, a stop sign left leaning, and a large metal porch awning was removed from the back of a home. This area was where peak intensity (estimated wind speed of 90 MPH) was observed before weakening near the Chartiers-Houston Junior/Senior High School. ||The circulation periodically weakened and reintensified along the remainder of its path. Notable damage was observed along Linden Creek Rd where wheat was laid over, a barn lost shingles, and a narrow path of damage to hardwood trees was found. The circulation paralleled Venetia Rd where sporadic tree damage was observed. Modest intensification occurred near Finleyville where a few uprooted and snapped trees were observed, and a three story apartment building lost siding on its western face. The tornado dissipated close to Pennsylvania Route 88.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

The county was under a tornado watch, issued at 18:43 UTC and running to 21:50 UTC.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a Marginal Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:47 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The Pittsburgh radar (KPBZ), 34 km away, was scanning. The volume nearest the touchdown began at 20:50 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2025 tornado in PennsylvaniaEvery tornado in Pennsylvania since 1950Warnings in force in Pennsylvania nowThe forecast where you are

5 more were confirmed in the United States that day.

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.