Tornadoes · United States · Pennsylvania · 2005
F1 tornado, Mechanicsburg, Pennsylvania, August 30, 2005
This F1 tornado ran 2.0 miles across Cumberland County on August 30, 2005, touching down at 1:19 AM EDT and reaching 100 yards wide. It killed nobody.
The rating scale
Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.
F040 to 72 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
F173 to 112 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
F2113 to 157 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.
F3158 to 206 mph
Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.
F4207 to 260 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
F5261 to 318 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.
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.
The record
- Rating
- F1
- Date
- August 30, 2005
- Touchdown
- 1:19 AM EDT (05:19 UTC)
- Path length
- 2.0 miles (3.2 km)
- Path width
- 100 yards (91 m)
- Deaths
- 0
- Injuries
- 0
- County
- Cumberland County
- Touchdown point
- 40.170, -77.000
- Lift-off point
- 40.170, -77.000
- Record number
- 1086
What the Weather Service recorded
A strong F1 tornado with winds up to 110 mph touched down between Dillsburg in York County and Mechanicsburg in Cumberland County. Specifically, the tornado began about 12:17 am EST near the intersection of Old Route 15 and Creek Road just south of the Rose Garden subdivision in York County. The tornado moved north across Yellow Breeches Creek into Cumberland County around 12:19 am EST through the Ashcombe Farms South Development. It ended along Stumpstown Road about a half mile west of Route 15 at 12:22 am EST. The tornado path was about two and one half miles in length, and 100 yards wide.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
6 minutes of warning. NWS CTP issued a tornado warning for this county at 05:13 UTC, 6 minutes before the tornado touched down, in force until 06:00 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 05:13 UTC | 06:00 UTC | Tornado Warning | CTP |
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 forecast that day
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 00:55 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 air that afternoon
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.
Phillips Aaf/Abe, MD (KAPG), 12:00Z
6.7 hours after it, 109 km from the path. August 31, 2005.
- Mixed-layer CAPE
- 111 J/kg
- Mixed-layer CIN
- -147 J/kg
- Surface CAPE
- 2067 J/kg
- Mixed-layer LCL
- 876 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 191 m²/s²
- 0-3 km storm-relative helicity
- 266 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 6.3
- 0-3 km lapse rate
- 4.7 K/km
The radar
The State College radar (KCCX), 119 km away, was scanning. The volume nearest the touchdown began at 05:20 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.
What was reported nearby
Local storm reports within 60 km of the path, in the three hours either side.
| Time (UTC) | Report | Where | County | Remark |
|---|---|---|---|---|
| 04:25 UTC | TSTM WND DMG | Fairfield | Adams, PA | HORSE TRAILER OVERTURNED. |
| 04:56 UTC | TSTM WND DMG | 5 Ne Gettysburg | Adams, PA | NUMEROUS TREES DOWN AND SHED DAMAGED AT HUNTERSTOWN. |
| 04:56 UTC | TSTM WND DMG | 5 Ne Gettysburg | Adams, PA | PSBL TORNADO. EXTENSIVE DAMAGE AROUND HUNTERSTOWN. NUMEROUS TREES DOWN. 3 BARNS DESTROYED ON MILLAN ROAD. ANOTHER BARN DESTROYED ON HUNTERSTOWN ROAD. SEVERAL POLES SNAPPED OFF AND TREES TWISTED. |
| 04:56 UTC | TSTM WND DMG | 5 Ne Gettysburg | Adams, PA | NUMEROUS TREES DOWN. |
| 04:56 UTC | TSTM WND DMG | Heidlersburg | Adams, PA | 2 BARN ROOFS BLOWN OFF. NUMEROUS TREES DOWN. |
| 05:15 UTC | TSTM WND DMG | Dillsburg | York, PA | TREES UPROOTED. ONE FELL ON A BARN. POSSIBLE TORNADO. |
| 05:20 UTC | TSTM WND DMG | 2 S Mechanicsburg | Cumberland, PA | NUMEROUS TREES DOWN...SOME ON CARS AND HOMES. 1200 PEOPLE WITHOUT POWER. POSSIBLE TORNADO. |
| 05:27 UTC | TSTM WND DMG | Mechanicsburg | Cumberland, PA | NUMEROUS TREES DOWN. TRAMPOLINE BLOWN ON CAR. |
| 05:30 UTC | TSTM WND DMG | Mechanicsburg | Cumberland, PA | SEVERAL HOMES DAMAGED NEAR ASCO FARMS ALONG GREGOR COURT. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2005 tornado in PennsylvaniaEvery tornado in Pennsylvania since 1950Warnings in force in Pennsylvania nowThe forecast where you are
The other tornadoes of August 30, 2005
12 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| August 30 | 3:17 PM EDT | F1 | York, PA | 0.5 | 100 | |||
| August 30 | 5:45 PM EDT | F0 | Warren, OH | 2.0 | 300 | $20,000 | ||
| August 30 | 6:51 PM EDT | F0 | Madison, VA | 0.5 | 50 | $10,000 | ||
| August 30 | 7:05 PM EDT | F1 | Albemarle, VA | 1.0 | 100 | $500,000 | ||
| August 30 | 7:30 PM EDT | F0 | Culpeper, VA | 0.5 | 75 | $10,000 | ||
| August 30 | 7:35 PM EDT | F0 | Rappahannock, VA | 4.0 | 75 | $50,000 | ||
| August 30 | 8:08 PM EDT | F0 | Fauquier, VA | 0.8 | 75 | $50,000 | ||
| August 30 | 8:17 PM EDT | F1 | Fauquier, VA | 5.0 | 300 | $1.5 million | ||
| August 30 | 9:30 PM EDT | F1 | Macon, NC | 0.1 | 50 | |||
| August 30 | 12:22 AM EDT | F1 | Adams, PA | 3.0 | 200 | |||
| August 30 | 12:38 AM EDT | F1 | Adams, PA | 7.0 | 300 | |||
| August 30 | 12:40 AM EDT | F1 | Adams, PA | 3.0 | 50 |
What this means
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.
Sources
NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.