Tornadoes · United States · Alabama · 1996

F0 tornado, Birmingham, Alabama, April 20, 1996

This F0 tornado ran 0.3 miles across Jefferson County on April 20, 1996, touching down at 12:09 PM CDT and reaching 45 yards wide. It killed nobody, and did $70,000 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
April 20, 1996
Touchdown
12:09 PM CDT (17:09 UTC)
Path length
0.3 miles (0.5 km)
Path width
45 yards (41 m)
Deaths
0
Injuries
0
Property damage
$70,000
County
Jefferson County
Touchdown point
33.520, -86.820
Lift-off point
33.520, -86.820
Record number
136

What the Weather Service recorded

A small tornado touched down in the area of Five Points West in Birmingham with a number of trees down and some structural damage.

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

The warnings

9 minutes of warning. NWS BMX issued a tornado warning for this county at 17:00 UTC, 9 minutes before the tornado touched down, in force until 17:45 UTC.

Issued (UTC)ExpiredProductOffice
16:53 UTC17:45 UTCSevere Thunderstorm WarningBMX
17:00 UTC17:45 UTCTornado WarningBMX
00:07 UTC01:00 UTCSevere Thunderstorm WarningBMX
03:39 UTC04:45 UTCSevere Thunderstorm WarningBMX
04:11 UTC04:45 UTCTornado WarningBMX

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. The outlook in force was issued at 05:43 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.

Birmingham, AL (KBMX), 12:00Z

5.2 hours before the tornado, 38 km from the path. April 20, 1996.

Skew-T log-pSkew-T log-p diagram, Birmingham, AL at 12:00Z on 1996-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 816 joules per kilogram, CIN -15, lifted condensation level 527 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, Birmingham, AL at 12:00Z on 1996-04-20The 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 229 square meters per square second, 0 to 6 km bulk shear 41 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
816 J/kg
Mixed-layer CIN
-15 J/kg
Surface CAPE
985 J/kg
Mixed-layer LCL
527 m above ground
0-6 km bulk shear
41 kt
0-1 km bulk shear
29 kt
0-1 km storm-relative helicity
229 m²/s²
0-3 km storm-relative helicity
330 m²/s²
Significant tornado parameter
1.0
Supercell composite
5.6
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

Birmingham, AL (KBMX), 00:00Z

6.8 hours after it, 38 km from the path. April 21, 1996.

Skew-T log-pSkew-T log-p diagram, Birmingham, AL at 00:00Z on 1996-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1416 joules per kilogram, CIN -57, lifted condensation level 837 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, Birmingham, AL at 00:00Z on 1996-04-21The 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 270 square meters per square second, 0 to 6 km bulk shear 45 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
1416 J/kg
Mixed-layer CIN
-57 J/kg
Surface CAPE
401 J/kg
Mixed-layer LCL
837 m above ground
0-6 km bulk shear
45 kt
0-1 km bulk shear
31 kt
0-1 km storm-relative helicity
270 m²/s²
0-3 km storm-relative helicity
358 m²/s²
Significant tornado parameter
0.0
Supercell composite
12.7
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1996 tornado in AlabamaEvery tornado in Alabama since 1950Warnings in force in Alabama nowThe forecast where you are

The other tornadoes of April 20, 1996

20 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 201:01 AM ESTF1Decatur, IN1.275$1.2 million
April 202:08 AM EDTF2Floyd, IN1.01001$250,000
April 202:40 AM EDTF1Bullitt, KY1.0200$300,000
April 203:30 AM CDTF1Barren, KY0.51004$10,000
April 203:34 AM CDTF1Barren, KY4.0200$80,000
April 203:45 AM CDTF0Green, KY3.0100$20,000
April 205:26 AM EDTF2Lincoln, KY12.03007$1.5 million
April 205:28 AM EDTF1Rockcastle, KY2.0100$40,000
April 205:30 AM EDTF1Garrard, KY6.0200$10,000
April 205:45 AM EDTF2Madison, KY2.020010$13 million
April 205:55 AM EDTF1Estill, KY5.0100$200,000
April 206:45 AM CDTF2Lawrence, TN0.520012$1.3 million
April 206:50 AM CDTF2Lawrence, TN1.0440
April 206:56 AM CDTF2Giles, TN1.0440
April 207:03 AM CDTF2Marshall, TN1.5440
April 208:40 AM CDTF1Carroll, MS6.0200$100,000
April 201:50 PM EDTF0McDowell, NC0.130$20,000
April 202:00 PM EDTF1Watauga, NC0.1202$50,000
April 204:15 PM CDTF1Shelby, TX5.0250
April 204:45 PM CDTF0De Soto Parish, LA0.525

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.