Tornadoes · United States · Pennsylvania · 2005

F0 tornado, Towanda, Pennsylvania, August 12, 2005

This F0 tornado ran 1.0 miles across Bradford County on August 12, 2005, touching down at 5:10 PM EDT and reaching 200 yards wide. It killed nobody, and did $100,000 of property damage.

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.

  1. F040 to 72 mphthis tornado

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

  2. F173 to 112 mph

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

  3. 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.

  4. 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.

  5. F4207 to 260 mph

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

  6. 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.

  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.

The record

Rating
F0
Date
August 12, 2005
Touchdown
5:10 PM EDT (21:10 UTC)
Path length
1.0 miles (1.6 km)
Path width
200 yards (183 m)
Deaths
0
Injuries
0
Property damage
$100,000
County
Bradford County
Touchdown point
41.750, -76.430
Lift-off point
41.750, -76.430
Record number
343

What the Weather Service recorded

The tornado initially touched down somewhere between South 4th Street and Olive Street to the southwest of Memorial Park Drive in South Towanda. The tornado then moved toward the southeast through a neighborhood between Thomas Street, 2nd Street, and Olive Street to Grant Street. The tornado crossed South Main Street near the American Legion, and then tracked down across Railroad Road before lifting near the Susquehanna River. Damage path about 1 mile long and up to 200 yards wide. Most of the damage associated with this small tornado was to trees and power lines. There were a few homes that lost some shingles and siding. One home along South Main Street across from the American Legion lost a small portion of its roof.

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

Issued (UTC)ExpiredProductOffice
19:51 UTC20:45 UTCSevere Thunderstorm WarningBGM
20:54 UTC22:00 UTCSevere Thunderstorm WarningBGM

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 20:09 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.

Buffalo Intl Airport, NY (KBUF), 12:00Z

9.2 hours before the tornado, 228 km from the path. August 12, 2005.

Skew-T log-pSkew-T log-p diagram, Buffalo Intl Airport, NY at 12:00Z on 2005-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -75260, lifted condensation level 1425 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Buffalo Intl Airport, NY at 12:00Z on 2005-08-12The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 126 square meters per square second, 0 to 6 km bulk shear 38 knots.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
-75260 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1425 m above ground
0-6 km bulk shear
38 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
126 m²/s²
0-3 km storm-relative helicity
186 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.6 K/km

Open this sounding in Storm Lab

Buffalo Intl Airport, NY (KBUF), 00:00Z

2.8 hours after it, 228 km from the path. August 13, 2005.

Skew-T log-pSkew-T log-p diagram, Buffalo Intl Airport, NY at 00:00Z on 2005-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 434 joules per kilogram, CIN -45, lifted condensation level 1414 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Buffalo Intl Airport, NY at 00:00Z on 2005-08-13The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 103 square meters per square second, 0 to 6 km bulk shear 25 knots.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
434 J/kg
Mixed-layer CIN
-45 J/kg
Surface CAPE
1178 J/kg
Mixed-layer LCL
1414 m above ground
0-6 km bulk shear
25 kt
0-1 km bulk shear
28 kt
0-1 km storm-relative helicity
103 m²/s²
0-3 km storm-relative helicity
106 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.9
0-3 km lapse rate
6.6 K/km

Open this sounding in Storm Lab

The surface observations

Elmira / Corning (ELM), 60 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
19:19 UTC75.269.8350° 12 kt271014.6TSRA
19:30 UTC73.469.860° 10 kt181014.6-TSRA BR
19:41 UTC73.469.880° 5 kt1014.9TSRA BR
19:53 UTC74710° 0 kt1014.9-TSRA BR
20:53 UTC7472220° 4 kt1014.6BR
21:53 UTC7672140° 4 kt1013.5BR
22:53 UTC7571130° 4 kt1013.2

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

The radar

The Binghamton radar (KBGM), 62 km away, was scanning. The volume nearest the touchdown began at 21:09 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)ReportWhereCountyRemark
19:55 UTCTSTM WND DMGUlsterBradford, PATREES DOWN THROUGHOUT THE NORTHEASTERN PART OF THE COUNTY.
20:15 UTCTSTM WND DMGBrackneySusquehanna, PATREES DOWN IN LIBERTY AND SILVER LAKE TOWNSHIPS.
20:20 UTCTSTM WND DMG9 N Muncy ValleySullivan, PAMULTIPLE TREES/WIRES DOWN
20:30 UTCHAIL 1ShunkSullivan, PA
21:10 UTCHAIL 0.25TowandaBradford, PAALSO TREES DOWN.
21:10 UTCHAIL 0.75TowandaBradford, PAALSO TREES DOWN.
21:10 UTCTORNADOTowandaBradford, PAPOSSIBLE TORNADO. NWS SURVEY TO BE CONDUCTED SATURDAY.
21:15 UTCTSTM WND DMGCentralColumbia, PATREES/WIRES/POLES DOWN
21:25 UTCTSTM WND DMGRed RockLuzerne, PATREES AND POWER LINES DOWN IN FAIRMOUNT AND ROSS TWPS.

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 12, 2005

7 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 122:24 PM EDTF0Allegany, NY0.510$10,000
August 122:45 PM EDTF1Steuben, NY1.0200$50,000
August 124:22 PM EDTF1Sullivan, PA0.730$10,000
August 125:56 PM EDTF0Polk, FL0.540
August 124:40 PM MDTF2Campbell, WY1.5450213$5.0 million
August 127:05 PM MDTF0Converse, WY0.130
August 129:45 PM EDTF1Nassau, NY0.250$140,000

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.