Tornadoes · United States · Florida · 2003

F2 tornado, Grand Ridge, Florida, March 20, 2003

This F2 tornado ran 8.0 miles across Jackson County on March 20, 2003, touching down at 2:50 AM CST and reaching 300 yards wide. It killed nobody and injured 3, and did $500,000 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 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
March 20, 2003
Touchdown
2:50 AM CST (08:50 UTC)
Path length
8.0 miles (12.9 km)
Path width
300 yards (274 m)
Deaths
0
Injuries
3
Property damage
$500,000
County
Jackson County
Touchdown point
30.700, -85.050
Lift-off point
30.770, -84.920
Record number
46

What the Weather Service recorded

A tornado touched down in Cypress, just west of Grand Ridge, and traveled northeast before lifting to the north of Sneads. Two mobile homes and a single-family home were destroyed. 15 single-family and mobile homes were damaged. Numerous trees and power lines were down. One person was seriously injured and two sustained minor injuries. Reported by the Jackson County EMA and CAP/NWS aerial survey team.

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

The warnings

31 minutes of warning. NWS TAE issued a tornado warning for this county at 08:19 UTC, 31 minutes before the tornado touched down, in force until 09:00 UTC.

Issued (UTC)ExpiredProductOffice
08:19 UTC09:00 UTCTornado WarningTAE
08:56 UTC09:45 UTCTornado WarningTAE

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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 06:07 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.

Tallahassee Rgnl, FL (KTLH), 00:00Z

8.8 hours before the tornado, 75 km from the path. March 20, 2003.

Skew-T log-pSkew-T log-p diagram, Tallahassee Rgnl, FL at 00:00Z on 2003-03-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1137 joules per kilogram, CIN -2, lifted condensation level 511 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, Tallahassee Rgnl, FL at 00:00Z on 2003-03-20The 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 140 square meters per square second, 0 to 6 km bulk shear 61 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
1137 J/kg
Mixed-layer CIN
-2 J/kg
Surface CAPE
1334 J/kg
Mixed-layer LCL
511 m above ground
0-6 km bulk shear
61 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
140 m²/s²
0-3 km storm-relative helicity
162 m²/s²
Significant tornado parameter
0.9
Supercell composite
4.3
0-3 km lapse rate
5.6 K/km

Open this sounding in Storm Lab

Tallahassee Rgnl, FL (KTLH), 12:00Z

3.2 hours after it, 75 km from the path. March 20, 2003.

Skew-T log-pSkew-T log-p diagram, Tallahassee Rgnl, FL at 12:00Z on 2003-03-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1287 joules per kilogram, CIN 0, lifted condensation level 472 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, Tallahassee Rgnl, FL at 12:00Z on 2003-03-20The 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 271 square meters per square second, 0 to 6 km bulk shear 66 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
1287 J/kg
Mixed-layer CIN
0 J/kg
Surface CAPE
1357 J/kg
Mixed-layer LCL
472 m above ground
0-6 km bulk shear
66 kt
0-1 km bulk shear
37 kt
0-1 km storm-relative helicity
271 m²/s²
0-3 km storm-relative helicity
305 m²/s²
Significant tornado parameter
2.4
Supercell composite
7.7
0-3 km lapse rate
5.7 K/km

Open this sounding in Storm Lab

The surface observations

Mariana (MAI), 22 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
06:53 UTC7271250° 6 kt1006.4-RA
07:26 UTC71.671.6200° 6 kt1006.4-RA
07:38 UTC71.671.6 5 kt1006.1RA BR
07:53 UTC7171210° 5 kt1006.8+RA BR
08:15 UTC71.669.80° 0 kt1005.8RA BR
08:33 UTC69.869.8360° 7 kt1005.1+RA BR
08:38 UTC69.869.8300° 8 kt1006.1+RA BR
08:45 UTC69.869.810° 7 kt1005.4+RA BR
08:53 UTC7070 3 kt1005.1+RA BR
09:53 UTC6969150° 5 kt1005.4-RA
10:14 UTC69.869.8150° 7 kt1005.4-RA

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

The radar

The Tallahassee radar (KTLH), 73 km away, was scanning. The volume nearest the touchdown began at 08:50 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.

This ground now

The live radar over the trackEvery 2003 tornado in FloridaEvery tornado in Florida since 1950Warnings in force in Florida nowThe forecast where you are

The other tornadoes of March 20, 2003

4 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
March 205:05 AM ESTF3Mitchell, GA25.06006200$6.8 million
March 201:25 PM ESTF0Bacon, GA0.10
March 201:35 PM ESTF0Wayne, GA0.10
March 202:15 PM ESTF0Atkinson, GA0.10

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.