Tornadoes · United States · Florida · 2007

EF0 tornado, (Nrb)Nas Mayport, Florida, July 14, 2007

This EF0 tornado ran 0.8 miles across Duval County on July 14, 2007, touching down at 1:56 PM EDT and reaching 50 yards wide. It killed nobody.

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
July 14, 2007
Touchdown
1:56 PM EDT (17:56 UTC)
Lifted
1:58 PM EDT (17:58 UTC)
On the ground
2 minutes
Path length
0.8 miles (1.2 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Duval County
Touchdown point
30.380, -81.424
Lift-off point
30.380, -81.412
Record number
0707141156-01

What the Weather Service recorded

A quasi-stationary front just north of the Altamaha River, the sea breezes, surface based instability and upper level positive differential vorticity advection all merged to spawn scattered severe storms across our forecast area in the afternoon and evening.

Military observers reported a brief tornado touchdown on base. The vortex was on the ground for around 2 minutes. It blew out windows from a three story barracks building and blew around heavy equipment. No injuries were reported.

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.

Issued (UTC)ExpiredProductOffice
17:59 UTC18:36 UTCSevere Thunderstorm 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. The outlook in force was issued at 16:23 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

5.9 hours before the tornado, 30 km from the path. July 14, 2007.

Skew-T log-pSkew-T log-p diagram, Jacksonville, FL at 12:00Z on 2007-07-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1651 joules per kilogram, CIN -26, lifted condensation level 615 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, Jacksonville, FL at 12:00Z on 2007-07-14The 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 39 square meters per square second, 0 to 6 km bulk shear 14 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
1651 J/kg
Mixed-layer CIN
-26 J/kg
Surface CAPE
179 J/kg
Mixed-layer LCL
615 m above ground
0-6 km bulk shear
14 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
39 m²/s²
0-3 km storm-relative helicity
22 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.3 K/km

Open this sounding in Storm Lab

Jacksonville, FL (KJAX), 00:00Z

6.1 hours after it, 30 km from the path. July 15, 2007.

Skew-T log-pSkew-T log-p diagram, Jacksonville, FL at 00:00Z on 2007-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1314 joules per kilogram, CIN -21, lifted condensation level 866 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, Jacksonville, FL at 00:00Z on 2007-07-15The 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 123 square meters per square second, 0 to 6 km bulk shear 17 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
1314 J/kg
Mixed-layer CIN
-21 J/kg
Surface CAPE
2791 J/kg
Mixed-layer LCL
866 m above ground
0-6 km bulk shear
17 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
123 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.7
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

The surface observations

Mayport Ns (NRB), 1 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
19:55 UTC76720° 0 kt1015.2BR

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

The radar

The Jacksonville radar (KJAX), 30 km away, was scanning. The volume nearest the touchdown began at 17:56 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
17:00 UTCTSTM WND DMGOrange ParkClay, FLPOWER POLES DOWN.
17:12 UTCTSTM WND DMGOrange ParkClay, FLLARGE TREE LIMB FELL ON POWERLINE RESULTING IN LOSS OF POWER
17:55 UTCFUNNEL CLOUDMayportDuval, FLMOVING OFFSHORE. REPORTED BY MILITARY OBSERVERS.
17:56 UTCTORNADOMayportDuval, FLTORNADO TOUCHED DOWN FOR 2 MINUTES ON BASE AND DID DAMAGE TO A SMALL BUILDING. REPORTED BY MILITARY OBSERVER.
18:00 UTCLIGHTNINGTalbot IslandDuval, FL*** 2 INJ *** TWO PERSONS INJURED BY LIGHTNING STRIKE AT A LITTLE TALBOT ISLAND PICNIC PAVILION.
18:00 UTCMARINE TSTM WIND 0Ne MayportDuval, FLFOUR PERSONS IN OVERTURNED BOAT OFFSHORE MAYPORT. NRB ASOS HAD GUST TO 32 KNOTS. UNKNOWN IF ANYONE WAS INJURED.
18:00 UTCWATER SPOUTMayportDuval, FLFUNNEL CLOUD BRIEFLY TOUCHED DOWN AS WATERSPOUT IN MAYPORT SHIP BASIN. REPORTED BY MILITARY OBSERVERS.
18:10 UTCTSTM WND DMGYuleeNassau, FLTREE BRANCHES DOWN AND 2 TREES UPROOTED.
18:30 UTCTSTM WND DMGLittle Talbot IslandDuval, FLTREES DOWN IN THE TALBOT STATE PARK AREA ON SATURDAY. VERY FREQUENT LIGHTNING REPORTED AS WELL. TIME IS ESTIMATED.

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

This ground now

The live radar over the trackEvery 2007 tornado in FloridaEvery tornado in Florida since 1950Warnings in force in Florida nowThe forecast where you are

The other tornadoes of July 14, 2007

1 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 147:00 PM CDTEF0Doniphan, KS0.125

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.