EF0 tornado, Lincolnway to West York, Pennsylvania, April 16, 2011

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

April 16, 2011

Touchdown

8:20 PM EDT (00:20 UTC)

Lifted

8:21 PM EDT (00:21 UTC)

On the ground

1 minutes

Path length

0.5 miles (0.8 km)

Path width

200 yards (183 m)

Deaths

0

Injuries

2

Property damage

$20,000

County

York County

Touchdown point

39.968, -76.779

Lift-off point

39.971, -76.771

Record number

1104161820-01

2 damage points were recorded along this path by NWS CTP, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 92 mph.

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

A dynamic frontal system moved across the Lower Susquehanna Valley during the late afternoon and evening, producing intense lines of heavy showers and thunderstorms. Very fast winds just off the surface combined with strong low-level vertical wind shear created a convective environment capable of producing a few weak tornadoes, particularly along the leading edge of narrow thunderstorm line segments. A weak, very brief EF0 tornado was confirmed near York during the late evening resulting in 2 minor injuries.

The NWS in State College along with York County Emergency Management officials confirmed a weak, brief, EF0 tornado touched-down in West Manchester Township a few miles west of York between 2020 and 2021 PM EDT. The EF0 tornado first produced damage just north of Brougher Lane where damage to trees, utility wires and several outbuildings occurred. Some minor damage to several homes also occurred in this area. The tornado damaged a canopy on a gas station and two billboards at the corner of Carlisle Road and Brougher Lane as it traveled northeast along a short 1/2 mile path. After crossing Carlisle Road, more tree damage was observed. A significant portion of a roof was removed off a business and blown across Brougher Lane near Haviland Road. The tornado briefly lifted but touched-down again at the West Manchester Mall. Several trees were uprooted and a large 40x40 foot skylight was lifted and blown across the roof of the mall. The damage indicators observed during the storm survey were consistent with a maximum wind speed of 85 mph, rating the tornado as a high-end EF0.

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

15 minutes of warning. NWS CTP issued a tornado warning for this county at 00:05 UTC, 15 minutes before the tornado touched down, in force until 00:30 UTC.

The county was under a tornado watch, issued at 20:41 UTC and running to 01:23 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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 20:03 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 Sterling radar (KLWX), 126 km away, was scanning. The volume nearest the touchdown began at 00:17 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

56 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.