Tornadoes · United States · Pennsylvania · 1983

F1 tornado, Bucks County, Pennsylvania, March 21, 1983

This F1 tornado ran 8.0 miles across Bucks County on March 21, 1983, touching down at 2:30 PM EST and reaching 50 yards wide. It killed nobody, and did $5,000 to $50,000 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 mph

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

  2. F173 to 112 mphthis tornado

    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
F1
Date
March 21, 1983
Touchdown
2:30 PM EST (19:30 UTC)
Path length
8.0 miles (12.9 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$5,000 to $50,000
County
Bucks County
Touchdown point
40.220, -75.080
Lift-off point
40.300, -74.980
Record number
102

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.

Atlantic City In, NJ (KACY), 12:00Z

7.5 hours before the tornado, 101 km from the path. March 21, 1983.

Skew-T log-pSkew-T log-p diagram, Atlantic City In, NJ at 12:00Z on 1983-03-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 79 joules per kilogram, CIN -50, lifted condensation level 565 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, Atlantic City In, NJ at 12:00Z on 1983-03-21The 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 168 square meters per square second, 0 to 6 km bulk shear 51 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
79 J/kg
Mixed-layer CIN
-50 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
565 m above ground
0-6 km bulk shear
51 kt
0-1 km bulk shear
22 kt
0-1 km storm-relative helicity
168 m²/s²
0-3 km storm-relative helicity
247 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5
0-3 km lapse rate
4.1 K/km

Open this sounding in Storm Lab

Atlantic City In, NJ (KACY), 00:00Z

4.5 hours after it, 101 km from the path. March 22, 1983.

Skew-T log-pSkew-T log-p diagram, Atlantic City In, NJ at 00:00Z on 1983-03-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 290 joules per kilogram, CIN -28, lifted condensation level 899 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, Atlantic City In, NJ at 00:00Z on 1983-03-22The 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 -11 square meters per square second, 0 to 6 km bulk shear 52 knots.1939587897Sfc1 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
290 J/kg
Mixed-layer CIN
-28 J/kg
Surface CAPE
165 J/kg
Mixed-layer LCL
899 m above ground
0-6 km bulk shear
52 kt
0-1 km bulk shear
8 kt
0-1 km storm-relative helicity
-11 m²/s²
0-3 km storm-relative helicity
104 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.9
0-3 km lapse rate
7.3 K/km

Open this sounding in Storm Lab

The surface observations

Willow Grove Nas (NXX), 12 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
18:00 UTC5754200° 12 kt17988.8
18:42 UTC210° 11 kt987.8
19:00 UTC5956210° 10 kt987.8
19:13 UTC220° 5 kt16987.8
19:24 UTC270° 14 kt22988.8
19:40 UTC260° 11 kt18988.8
20:00 UTC6053290° 10 kt19989.2
21:00 UTC5948310° 12 kt17990.2

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

This ground now

The live radar over the trackEvery 1983 tornado in PennsylvaniaEvery tornado in Pennsylvania since 1950Warnings in force in Pennsylvania nowThe forecast where you are

The other tornadoes of March 21, 1983

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
March 215:30 AM ESTF2Okeechobee, FL5.0504$500,000 to $5 million
March 217:00 AM ESTF0Pamlico, NC0.117$5,000 to $50,000
March 217:10 AM ESTF1Hyde, NC12.033$50,000 to $500,000

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.