Tornadoes · United States · Florida · 2009

EF0 tornado, Tom Brown Park, Florida, June 4, 2009

This EF0 tornado ran 0.1 miles across Leon County on June 4, 2009, touching down at 11:10 AM EDT and reaching 25 yards wide. It killed nobody, and did $1.3 million of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. EF065 to 85 mphthis tornado

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

  2. EF186 to 110 mph

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

  3. EF2111 to 135 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. EF3136 to 165 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. EF4166 to 200 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. EF5over 200 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
EF0
Date
June 4, 2009
Touchdown
11:10 AM EDT (15:10 UTC)
Lifted
11:11 AM EDT (15:11 UTC)
On the ground
1 minutes
Path length
0.1 miles (0.1 km)
Path width
25 yards (23 m)
Deaths
0
Injuries
0
Property damage
$1.3 million
County
Leon County
Touchdown point
30.437, -84.214
Lift-off point
30.438, -84.213
Record number
0906040910-01

What the Weather Service recorded

A weak tornado briefly touched down at a school just east of Tallahassee on the 4th.

A small tornado briefly touched down at the Apalachee Elementary School. It mangled the metal roof of the main building. The damage was confined to a small area about 100 yards long by 25 yards wide. Maximum winds were estimated at 65 to 70 mph, which was consistent with EF0 tornado damage.

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

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 General Thunderstorms Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 12:52 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), 12:00Z

3.2 hours before the tornado, 9 km from the path. June 4, 2009.

Skew-T log-pSkew-T log-p diagram, Tallahassee Rgnl, FL at 12:00Z on 2009-06-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 608 joules per kilogram, CIN -16, lifted condensation level 679 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 2009-06-04The 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 88 square meters per square second, 0 to 6 km bulk shear 15 knots.1939Sfc1 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
608 J/kg
Mixed-layer CIN
-16 J/kg
Surface CAPE
320 J/kg
Mixed-layer LCL
679 m above ground
0-6 km bulk shear
15 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
88 m²/s²
0-3 km storm-relative helicity
109 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.5 K/km

Open this sounding in Storm Lab

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

8.8 hours after it, 9 km from the path. June 5, 2009.

Skew-T log-pSkew-T log-p diagram, Tallahassee Rgnl, FL at 00:00Z on 2009-06-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 343 joules per kilogram, CIN -20, lifted condensation level 957 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 2009-06-05The 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 93 square meters per square second, 0 to 6 km bulk shear 23 knots.1939Sfc1 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
343 J/kg
Mixed-layer CIN
-20 J/kg
Surface CAPE
1401 J/kg
Mixed-layer LCL
957 m above ground
0-6 km bulk shear
23 kt
0-1 km bulk shear
18 kt
0-1 km storm-relative helicity
93 m²/s²
0-3 km storm-relative helicity
102 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.5
0-3 km lapse rate
6.5 K/km

Open this sounding in Storm Lab

The surface observations

Tallahassee Regional (TLH), 14 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
13:53 UTC7672180° 4 kt1013.5
14:24 UTC75.273.40° 0 kt1013.5TSRA BR
14:33 UTC75.273.4300° 7 kt1013.2+TSRA BR
14:43 UTC73.471.6250° 16 kt221013.5+TSRA
14:47 UTC71.669.8240° 12 kt221013.2+TSRA
14:53 UTC7371210° 9 kt181012.9+TSRA
15:12 UTC73.471.6160° 7 kt1013.2TS
15:43 UTC75.271.6190° 4 kt1012.9-RA
15:53 UTC7572190° 3 kt1012.5-RA
16:53 UTC7972230° 13 kt201012.2
17:09 UTC71.669.8260° 12 kt231012.9-RA

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

The radar

The Tallahassee radar (KTLH), 12 km away, was scanning. The volume nearest the touchdown began at 15:09 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.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
15:10 UTCTSTM WND DMG4 E TallahasseeLeon, FLMINOR METAL ROOF DAMAGE TO APALACHEE ELEMENTARY SCHOOL. TIME ESTIMATED FROM RADAR.
15:10 UTCTORNADO 04 E TallahasseeLeon, FLCONFIRMED BRIEF TORNADO TOUCHDOWN AT APALACHEE ELEMENTARY SCHOOL. MAJOR DAMAGE TO A PORTION OF THE ROOF OF THE MAIN BUILDING. THE DAMAGE WAS CONFINED TO A SMALL AREA GENERALLY 100 YARDS LONG BY 25 YARDS WIDE. MAXIMUM WIN

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2009 tornado in FloridaEvery tornado in Florida since 1950Warnings in force in Florida nowThe forecast where you are

The other tornadoes of June 4, 2009

7 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 44:03 PM EDTEF0Glynn, GA2.175
June 44:17 PM CDTEF0Hartley, TX0.5100
June 43:35 PM PDTEF0Linn, OR1.5150$10,000
June 46:08 PM CDTEF0Oldham, TX1.0100
June 46:33 PM CDTEF0Randall, TX0.1100
June 46:40 PM CDTEF0Randall, TX0.8100
June 48:50 PM EDTEF0Worth, GA0.250$35,000

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.