Tornadoes · United States · Florida · 2017
EF1 tornado, Saint Johns County, Florida, June 6, 2017
This EF1 tornado ran 2.2 miles across Saint Johns County on June 6, 2017, touching down at 2:11 PM EDT and reaching 70 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.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- EF1
- Date
- June 6, 2017
- Touchdown
- 2:11 PM EDT (18:11 UTC)
- Lifted
- 2:16 PM EDT (18:16 UTC)
- On the ground
- 5 minutes
- Path length
- 2.2 miles (3.6 km)
- Path width
- 70 yards (64 m)
- Deaths
- 0
- Injuries
- 0
- County
- Saint Johns County
- Touchdown point
- 29.737, -81.312
- Lift-off point
- 29.753, -81.280
- Record number
- 1706061211-01
The damage survey
6 damage points were recorded along this path by NWS JAX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 95 mph.
- Complete failure of pool enclousure
- Numerous trees with trunks snapped
Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.
The warnings
5 minutes of warning. NWS JAX issued a tornado warning for this county at 18:06 UTC, 5 minutes before the tornado touched down, in force until 18:30 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 18:00 UTC | 18:30 UTC | Severe Thunderstorm Warning | JAX |
| 18:06 UTC | 18:30 UTC | Tornado Warning | JAX |
| 18:14 UTC | 20:15 UTC | Flood Advisory | JAX |
| 19:52 UTC | 00:29 UTC | Flood Watch | JAX |
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 Marginal Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 16:37 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
6.2 hours before the tornado, 92 km from the path. June 6, 2017.
- Mixed-layer CAPE
- 398 J/kg
- Mixed-layer CIN
- -12 J/kg
- Surface CAPE
- 723 J/kg
- Mixed-layer LCL
- 617 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- -49 m²/s²
- 0-3 km storm-relative helicity
- -63 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 5.3 K/km
Jacksonville, FL (KJAX), 00:00Z
5.8 hours after it, 92 km from the path. June 7, 2017.
- Mixed-layer CAPE
- 283 J/kg
- Mixed-layer CIN
- -273 J/kg
- Surface CAPE
- 1532 J/kg
- Mixed-layer LCL
- 998 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km bulk shear
- 4 kt
- 0-1 km storm-relative helicity
- 38 m²/s²
- 0-3 km storm-relative helicity
- 136 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
- 0-3 km lapse rate
- 4.8 K/km
The surface observations
St Augustine Airpt (SGJ), 24 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 16:15 UTC | 210° 6 kt | 1009.1 | ||||
| 16:20 UTC | 210° 7 kt | 1009.1 | ||||
| 16:25 UTC | 200° 7 kt | 1008.8 | ||||
| 16:30 UTC | 200° 7 kt | 1008.8 | -RA | |||
| 16:35 UTC | 200° 6 kt | 1008.8 | -RA | |||
| 16:40 UTC | 220° 6 kt | 1008.8 | ||||
| 16:45 UTC | 250° 4 kt | 1008.5 | ||||
| 16:55 UTC | 220° 5 kt | 1008.1 | ||||
| 16:56 UTC | 83 | 74 | 4 kt | 1008.1 | ||
| 17:00 UTC | 220° 5 kt | 1007.8 | ||||
| 17:05 UTC | 250° 5 kt | 1007.8 | ||||
| 17:10 UTC | 210° 6 kt | 1007.8 | ||||
| 17:15 UTC | 230° 6 kt | 1007.8 | ||||
| 17:20 UTC | 230° 5 kt | 1007.8 | ||||
| 17:25 UTC | 240° 5 kt | 1007.8 | ||||
| 17:30 UTC | 270° 6 kt | 1008.1 | HZ | |||
| 17:32 UTC | 82.4 | 73.4 | 280° 6 kt | 1008.1 | VCTS HZ | |
| 17:35 UTC | 270° 7 kt | 1008.1 | HZ | |||
| 17:40 UTC | 260° 6 kt | 1008.1 | HZ | |||
| 17:45 UTC | 290° 5 kt | 1007.8 | -RA | |||
| 17:50 UTC | 260° 6 kt | 1007.8 | RA | |||
| 17:55 UTC | 180° 11 kt | 1008.1 | +RA BR | |||
| 17:56 UTC | 79 | 75 | 170° 11 kt | 1008.1 | VCTS +RA BR | |
| 18:00 UTC | 190° 8 kt | 1007.8 | RA BR | |||
| 18:05 UTC | 200° 6 kt | 1007.5 | RA BR | |||
| 18:07 UTC | 75.2 | 73.4 | 210° 5 kt | 1007.8 | TSRA BR | |
| 18:10 UTC | 220° 7 kt | 1008.1 | RA BR | |||
| 18:15 UTC | 210° 7 kt | 1008.5 | +RA BR | |||
| 18:20 UTC | 180° 14 kt | 1008.1 | +RA BR | |||
| 18:25 UTC | 180° 11 kt | 1007.8 | RA BR | |||
| 18:30 UTC | 190° 9 kt | 1007.5 | -RA BR | |||
| 18:35 UTC | 230° 7 kt | 1007.8 | -RA BR | |||
| 18:40 UTC | 270° 8 kt | 1008.1 | -RA BR | |||
| 18:45 UTC | 250° 7 kt | 1008.8 | -RA BR | |||
| 18:50 UTC | 250° 7 kt | 1008.8 | -RA BR | |||
| 18:55 UTC | 260° 11 kt | 1008.5 | -RA BR | |||
| 18:56 UTC | 75 | 72 | 270° 9 kt | 1008.5 | -RA BR | |
| 19:00 UTC | 250° 9 kt | 1008.8 | -RA | |||
| 19:01 UTC | 73.4 | 71.6 | 260° 9 kt | 1008.8 | -TSRA | |
| 19:05 UTC | 260° 10 kt | 1008.8 | -RA BR | |||
| 19:08 UTC | 73.4 | 71.6 | 250° 8 kt | 1008.8 | -TSRA BR | |
| 19:10 UTC | 240° 6 kt | 1008.8 | -RA BR | |||
| 19:18 UTC | 73.4 | 73.4 | 230° 6 kt | 1009.1 | VCTS -RA BR | |
| 19:20 UTC | 210° 6 kt | 1009.1 | -RA BR | |||
| 19:25 UTC | 240° 4 kt | 1008.8 | RA BR | |||
| 19:30 UTC | 270° 5 kt | 1008.8 | -RA BR | |||
| 19:35 UTC | 270° 7 kt | 1008.5 | RA BR | |||
| 19:40 UTC | 270° 6 kt | 1008.5 | RA BR | |||
| 19:45 UTC | 250° 5 kt | 1008.5 | -RA BR | |||
| 19:47 UTC | 73.4 | 71.6 | 240° 5 kt | 1008.5 | -RA BR | |
| 19:50 UTC | 230° 4 kt | 1008.5 | -RA BR | |||
| 19:55 UTC | 250° 5 kt | 1008.5 | -RA BR | |||
| 19:56 UTC | 73 | 71 | 260° 5 kt | 1008.5 | -RA BR | |
| 20:00 UTC | 260° 5 kt | 1008.5 | -RA | |||
| 20:03 UTC | 73.4 | 71.6 | 280° 5 kt | 1008.5 | -RA | |
| 20:05 UTC | 270° 5 kt | 1008.5 | -RA BR | |||
| 20:10 UTC | 260° 7 kt | 1008.1 | BR |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Jacksonville radar (KJAX), 91 km away, was scanning. The volume nearest the touchdown began at 18:10 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 18:10 UTC | TORNADO 1 | 1 Se Dupont Center | St. Johns, FL | DAMAGE SURVEY ONGOING. PRELIMINARY RESULTS OF WEAK EF-1 DAMAGE. |
| 18:10 UTC | TORNADO | 1 Se Dupont Center | St. Johns, FL | TREES DOWN ON US 1 JUST SOUTH OF SR 206 SOUTH OF THE FLORIDA FOREST SERVICE TOWER, WITH REPORTS OF TREES BLOCKING ROADWAY. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2017 tornado in FloridaEvery tornado in Florida since 1950Warnings in force in Florida nowThe forecast where you are
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.