Tornadoes · United States · Florida · 1978

F2 tornado, Marion County, Florida, April 19, 1978

This F2 tornado ran 5.6 miles across Marion County on April 19, 1978, touching down at 10:03 AM EST and reaching 100 yards wide. It killed nobody and injured 14, and did $500,000 to $5 million 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 mph

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

  3. F2113 to 157 mphthis tornado

    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
F2
Date
April 19, 1978
Touchdown
10:03 AM EST (15:03 UTC)
Path length
5.6 miles (9.0 km)
Path width
100 yards (91 m)
Deaths
0
Injuries
14
Property damage
$500,000 to $5 million
County
Marion County
Touchdown point
29.070, -82.050
Lift-off point
29.100, -81.970
Record number
119

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.

Tampa Bay, FL (KTBW), 12:00Z

3.1 hours before the tornado, 158 km from the path. April 19, 1978.

Skew-T log-pSkew-T log-p diagram, Tampa Bay, FL at 12:00Z on 1978-04-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1028 joules per kilogram, CIN -47, lifted condensation level 928 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, Tampa Bay, FL at 12:00Z on 1978-04-19The 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 94 square meters per square second, 0 to 6 km bulk shear 38 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
1028 J/kg
Mixed-layer CIN
-47 J/kg
Surface CAPE
1530 J/kg
Mixed-layer LCL
928 m above ground
0-6 km bulk shear
38 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
127 m²/s²
Significant tornado parameter
0.4
Supercell composite
3.5
0-3 km lapse rate
4.8 K/km

Open this sounding in Storm Lab

Tampa Bay, FL (KTBW), 00:00Z

8.9 hours after it, 158 km from the path. April 20, 1978.

Skew-T log-pSkew-T log-p diagram, Tampa Bay, FL at 00:00Z on 1978-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 814 joules per kilogram, CIN -109, lifted condensation level 1334 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, Tampa Bay, FL at 00:00Z on 1978-04-20The 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 72 square meters per square second, 0 to 6 km bulk shear 46 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
814 J/kg
Mixed-layer CIN
-109 J/kg
Surface CAPE
2358 J/kg
Mixed-layer LCL
1334 m above ground
0-6 km bulk shear
46 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.1
Supercell composite
3.4
0-3 km lapse rate
6.6 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1978 tornado in FloridaEvery tornado in Florida since 1950Warnings in force in Florida nowThe forecast where you are

The other tornadoes of April 19, 1978

8 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 197:40 AM ESTF2Alachua, FL1.0506$50,000 to $500,000
April 1911:07 AM ESTF1Lake, FL1.050$50,000 to $500,000
April 195:43 PM ESTF2Duplin, NC11.670$50,000 to $500,000
April 196:00 PM ESTF1Robeson, NC13.433$500 to $5,000
April 196:25 PM ESTF2Onslow, NC3.3503$50,000 to $500,000
April 196:55 PM ESTF2Jones, NC0.730$50,000 to $500,000
April 197:00 PM ESTF1Madison, OH9.510$50,000 to $500,000
April 197:15 PM ESTF3Sussex, VA35.61003$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.