Tornadoes · United States · Alabama · 1983

F1 tornado, Mobile County, Alabama, December 11, 1983

This F1 tornado ran 0.1 miles across Mobile County on December 11, 1983, touching down at 3:15 AM CST and reaching 30 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
December 11, 1983
Touchdown
3:15 AM CST (09:15 UTC)
Path length
0.1 miles (0.2 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
Property damage
$5,000 to $50,000
County
Mobile County
Touchdown point
31.120, -88.180
Record number
914

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.

Eglin AFB/Valpar, FL (KVPS), 12:00Z

2.7 hours after it, 176 km from the path. December 11, 1983.

Skew-T log-pSkew-T log-p diagram, Eglin AFB/Valpar, FL at 12:00Z on 1983-12-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 856 joules per kilogram, CIN -13, lifted condensation level 523 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, Eglin AFB/Valpar, FL at 12:00Z on 1983-12-11The 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 190 square meters per square second, 0 to 6 km bulk shear 44 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
856 J/kg
Mixed-layer CIN
-13 J/kg
Surface CAPE
567 J/kg
Mixed-layer LCL
523 m above ground
0-6 km bulk shear
44 kt
0-1 km bulk shear
25 kt
0-1 km storm-relative helicity
190 m²/s²
0-3 km storm-relative helicity
337 m²/s²
Significant tornado parameter
1.0
Supercell composite
6.9
0-3 km lapse rate
5.2 K/km

Open this sounding in Storm Lab

This ground now

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

The other tornadoes of December 11, 1983

9 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
December 1112:30 AM CSTF1Saint Helena Parish, LA0.52004$50,000 to $500,000
December 111:05 AM CSTF1Tangipahoa Parish, LA2.0150$50,000 to $500,000
December 111:58 AM CSTF1Forrest, MS0.673$50,000 to $500,000
December 112:00 AM CSTF1Jones, MS1.01001$50,000 to $500,000
December 116:30 AM CSTF1Okaloosa, FL0.530$500 to $5,000
December 1110:30 AM PSTF0Mendocino, CA2.0300$500 to $5,000
December 115:00 PM CSTF0Pickens, AL3.0100$5,000 to $50,000
December 116:45 PM CSTF1Tuscaloosa, AL0.5127$5,000 to $50,000
December 1111:00 PM ESTF2Pinellas, FL8.0100$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.