EF1 tornado, Hallton to Sigel, Pennsylvania, October 16, 2021

1. EF065 to 85 mph

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

2. EF186 to 110 mphthis tornado

   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

EF1

Date

October 16, 2021

Touchdown

8:08 AM EDT (12:08 UTC)

Lifted

8:10 AM EDT (12:10 UTC)

On the ground

2 minutes

Path length

1.2 miles (1.9 km)

Path width

260 yards (238 m)

Deaths

1

Injuries

1

Property damage

$170,000

Crop damage

$750,000

Counties

Jefferson and Elk counties

Touchdown point

41.350, -79.050

Lift-off point

41.358, -79.038

Record number

2110160608-01

1 damage points were recorded along this path by NWS PBZ, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 74 mph.

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

A tornado that touched down in Jefferson County during the morning of October 16,2021 crossed into Millstone Township in western Elk County, producing EF-1 damage in Elk County. The tornado had estimated peak winds of 90 mph, a path length of just over 0.6 miles, and a maximum path width of 260 yards.

A lone supercell, that advanced along a cold front, formed in the early morning hours of October 16th. This cell had a history of tornadoes before tracking into eastern Ohio and western PA. The supercell was located near a mesoscale low and/or mesoscale vortex, which supported locally enhanced helicity. Furthermore, this cell was in an area of relatively stronger low-level instability. Surface dew points were favorable, low/mid 60s, prior to touch down and there were backed surface winds.

An EF-1 tornado was confirmed to have occurred in in Millstone Township, western Elk County during the morning of October 16, 2021. The tornado touched down in Jefferson County, PA and crossed the Clarion River into western Elk County around 8:08am. Maximum estimated wind speeds of 90 mph knocked down and uprooted several trees along River Road. One tree fell onto a cabin, and a hunter who was in a tree-stand was injured. The tornado had a maximum path width of 260 yards, and the path length in Elk County was a little over 0.6 miles.

The National Weather Service in Pittsburgh conducted a tornado survey along the Clarion River that straddles Jefferson and Elk County. ||A weak EF0 tornado moved north northeast shortly after daybreak on Saturday October 16th. This resulted in damage to softwood and hardwood trees along the Jefferson County side of the Clarion River along State Route 949. More significant damage (EF1) was observed on the Elk County side, along River Road. The tornado lifted just prior to reaching Bridge Road. Estimated Maximum Wind Speed...85 mph.||Estimated cost of damage was provided by the county emergency manager.

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.

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 General Thunderstorms Risk. The outlook in force was issued at 05:03 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 radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

The State College radar (KCCX), 99 km away, was scanning. The volume nearest the touchdown began at 12:08 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 2021 tornado in PennsylvaniaEvery tornado in Pennsylvania since 1950Warnings in force in Pennsylvania nowThe forecast where you are

4 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.