EF2 tornado, Cocolamus to Richfield, Pennsylvania, May 23, 2011

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 mph

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

3. EF2111 to 135 mphthis tornado

   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

EF2

Date

May 23, 2011

Touchdown

5:23 PM EDT (21:23 UTC)

Lifted

5:31 PM EDT (21:31 UTC)

On the ground

8 minutes

Path length

4.7 miles (7.6 km)

Path width

250 yards (229 m)

Deaths

0

Injuries

0

Property damage

$50,000

County

Juniata County

Touchdown point

40.652, -77.191

Lift-off point

40.652, -77.101

Record number

1105231523-01

An upper level disturbance moved out of the Ohio Valley and triggered severe thunderstorms and tornadoes across portions of central and eastern Pennsylvania. A total of 3 tornadoes were confirmed ranging in magnitude from EF1-EF2.

The NWS State College confirmed a EF2 tornado near Kellerville in Juniata County. The tornado touched down around 1723 EDT about 1/4 mile west of 1332 Kellerville Road and traveled east approximately 5 miles before lifting just east of 7 Stars Road around 1731 EDT.||The tornado laid a pattern in a hay field before crossing Kellerville Road where it toppling a concrete silo which fell on and obliterated a cow barn, killing 7 dairy cows. The house south of the barn at 1332 Kellerville Road had the entire roof and attic portion blown off and was shifted on its foundation. Several outbuildings and sheds on the property were also obliterated. The debris and tornado moved southeastward with visible tree damage on the hill.||The tornado did considerable damage to a hamlet along Evendale Hill Road. A house at 3009 Evendale Hill Road lost its entire roof and attic and was shifted about 6 inches to north causing the north facing basement wall to bulge out. Roof materials and personal items from the attic were blown into trees and up the road to the north. The tornado ripped up and snapped virtually all trees along the hill behind the house and farm. Several outbuildings were damaged and a neighboring house was damaged. |The tornado continued to the east, snapping trees and causing minor to moderate damage to other houses and outbuildings along the path. Older sheds and farm outbuildings along this track sustained major damage or were destroyed. Near the end of its track, the tornado tore apart a garage attached to a recently built house at 2787 Seven Stars Road. The house itself was also shifted on its foundation. The resident of this home heard a loud noise and witnessed the tornado in the valley heading towards him and took cover. The tornado dissipated to the east of this home, in a wooded area to the west of Peanut Road.||Overall, this tornado produced an approximate 4.7-mile-long swath of nearly continuous damage. The damage indicators were consistent with peak winds between 115 and 130 mph. Overall, a total of 7 homes sustained damage ranging from minor to major, and 15 barns and outbuildings either severely damaged or completely destroyed. There were no injuries or fatalities.

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

8 minutes of warning. NWS CTP issued a tornado warning for this county at 21:15 UTC, 8 minutes before the tornado touched down, in force until 21:45 UTC.

The county was under a severe thunderstorm watch, issued at 14:48 UTC and running to 22:00 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 Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:39 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.

Selinsgrove (SEG), 30 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The State College radar (KCCX), 78 km away, was scanning. The volume nearest the touchdown began at 21:23 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 2011 tornado in PennsylvaniaEvery tornado in Pennsylvania since 1950Warnings in force in Pennsylvania nowThe forecast where you are

17 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.