Tornadoes · United States · Florida · 2004

F0 tornado, Saint Johns County, Florida, September 5, 2004

This F0 tornado ran 3.0 miles across Saint Johns County on September 5, 2004, touching down at 9:25 AM EDT and reaching 75 yards wide. It killed nobody, and did $80,000 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
September 5, 2004
Touchdown
9:25 AM EDT (13:25 UTC)
Path length
3.0 miles (4.8 km)
Path width
75 yards (69 m)
Deaths
0
Injuries
0
Property damage
$80,000
County
Saint Johns County
Touchdown point
29.650, -81.370
Lift-off point
29.650, -81.370
Record number
445

The warnings

9 minutes of warning. NWS JAX issued a tornado warning for this county at 13:16 UTC, 9 minutes before the tornado touched down, in force until 13:30 UTC.

Issued (UTC)ExpiredProductOffice
06:40 UTC07:30 UTCTornado WarningJAX
08:51 UTC09:15 UTCTornado WarningJAX
13:16 UTC13:30 UTCTornado WarningJAX
20:53 UTC21:45 UTCTornado WarningJAX
03:56 UTC04:30 UTCTornado WarningJAX

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 12:47 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.

Jacksonville, FL (KJAX), 12:00Z

1.4 hours before the tornado, 100 km from the path. September 5, 2004.

Skew-T log-pSkew-T log-p diagram, Jacksonville, FL at 12:00Z on 2004-09-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1587 joules per kilogram, CIN -4, lifted condensation level 734 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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, Jacksonville, FL at 12:00Z on 2004-09-05The 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 166 square meters per square second, 0 to 6 km bulk shear 16 knots.193958Sfc1 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
1587 J/kg
Mixed-layer CIN
-4 J/kg
Surface CAPE
2428 J/kg
Mixed-layer LCL
734 m above ground
0-6 km bulk shear
16 kt
0-1 km bulk shear
29 kt
0-1 km storm-relative helicity
166 m²/s²
0-3 km storm-relative helicity
205 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.3 K/km

Open this sounding in Storm Lab

Jacksonville, FL (KJAX), 00:00Z

10.6 hours after it, 100 km from the path. September 6, 2004.

Skew-T log-pSkew-T log-p diagram, Jacksonville, FL at 00:00Z on 2004-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 498 joules per kilogram, CIN -1, lifted condensation level 529 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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, Jacksonville, FL at 00:00Z on 2004-09-06The 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 95 square meters per square second, 0 to 6 km bulk shear 28 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
498 J/kg
Mixed-layer CIN
-1 J/kg
Surface CAPE
1040 J/kg
Mixed-layer LCL
529 m above ground
0-6 km bulk shear
28 kt
0-1 km bulk shear
18 kt
0-1 km storm-relative helicity
95 m²/s²
0-3 km storm-relative helicity
110 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.5
0-3 km lapse rate
5.5 K/km

Open this sounding in Storm Lab

The radar

The Jacksonville radar (KJAX), 98 km away, was scanning. The volume nearest the touchdown began at 13:22 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
14:27 UTCTROPICAL STORM10 Sw Palm CoastFlagler, FLWIND GUST TO 50 MPH WITH 2.01 INCHES OF RAIN IN KORONA.
14:27 UTCBLIZZARD10 Sw Palm CoastFlagler, FLWIND GUSTS TO 50 MPH WITH 2.01 INCHES OF RAIN SINCE THIS MORNING.
14:38 UTCTROPICAL STORMFlagler BeachFlagler, FLSUSTAINED WINDS MEASURED AT 44 MPH.
14:38 UTCTROPICAL STORMFlagler BeachFlagler, FLSUSTAINED WINDS MEASURED AT 44 MPH. 1.08 INCHES OF RAIN SINCE THIS MORNING.
14:38 UTCTROPICAL STORMPalm CoastFlagler, FLWIND GUSTS TO 65 MPH WITH SHINGLES DOWN. WATER UP TO NEAR TOP OF SEA WALL.
14:38 UTCTROPICAL STORMPalm CoastFlagler, FLWIND GUST TO 65 MPH. SHINGLES BLOWN DOWN. WATER UP TO NEAR TOP OF SEA WALL.
16:08 UTCTROPICAL STORMPalm CoastFlagler, FLCANOPY OVER GAS STATION SPLIT...NUMEROUS TREES DOWN WITH POWER OUTAGES. 4.00 INCHES OF RAINFALL THROUGH NOON.

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

This ground now

The live radar over the trackEvery 2004 tornado in FloridaEvery tornado in Florida since 1950Warnings in force in Florida nowThe forecast where you are

The other tornadoes of September 5, 2004

26 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
September 55:05 AM EDTF0Saint Johns, FL5.075$10,000
September 56:05 AM EDTF0Marion, FL1.075
September 58:10 AM EDTF0Clay, FL1.075
September 59:20 AM EDTF0Flagler, FL0.575
September 52:30 PM EDTF0Suwannee, FL0.575
September 53:13 PM EDTF0Putnam, FL0.575
September 53:06 PM CDTF0Woodbury, IA12.0100$10,000
September 54:15 PM EDTF0Lowndes, GA0.250$10,000
September 53:20 PM CDTF2Otter Tail, MN4.0100$250,000
September 55:08 PM CDTF0Dickinson, IA0.150
September 55:15 PM CDTF0Jackson, MN2.050$2,000
September 56:50 PM EDTF0Putnam, FL10.075
September 57:00 PM EDTF0Alachua, FL5.075
September 56:04 PM CDTF1Greene, IA2.040$50,000
September 56:15 PM CDTF0Greene, IA0.525
September 56:40 PM CDTF0Pierce, WI1.025
September 57:15 PM CDTF0Hamilton, IA0.220
September 58:30 PM EDTF0McIntosh, GA0.350
September 57:52 PM CDTF0Warren, IA0.220
September 58:05 PM CDTF0Barron, WI0.325
September 58:48 PM CDTF0Lucas, IA2.050$70,000
September 58:51 PM CDTF0Polk, IA0.525$10,000
September 59:06 PM CDTF1Story, IA2.740$30,000
September 59:17 PM CDTF1Marshall, IA3.530$10,000
September 59:17 PM CDTF0Marshall, IA3.025$20,000
September 512:05 AM EDTF0Liberty, GA0.540

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.