Tornadoes · United States · Florida · 2023

EF0 tornado, Saint Johns County, Florida, September 11, 2023

This EF0 tornado ran 0.0 miles across Saint Johns County on September 11, 2023, touching down at 6:10 PM EDT and reaching 5 yards wide. It killed nobody, and did $75,000 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
September 11, 2023
Touchdown
6:10 PM EDT (22:10 UTC)
Path length
0.0 miles (0.0 km)
Path width
5 yards (5 m)
Deaths
0
Injuries
0
Property damage
$75,000
County
Saint Johns County
Touchdown point
29.850, -81.500
Lift-off point
29.850, -81.500
Record number
2309111610-01

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
18:01 UTC18:18 UTCSevere Thunderstorm WarningJAX
20:25 UTC21:00 UTCSevere Thunderstorm WarningJAX
20:55 UTC21:30 UTCSevere Thunderstorm WarningJAX
21:26 UTC22:00 UTCSevere Thunderstorm WarningJAX
21:50 UTC23:54 UTCFlood AdvisoryJAX
21:56 UTC22:45 UTCSevere Thunderstorm WarningJAX
22:44 UTC23:30 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 Marginal Risk. The outlook in force was issued at 19:42 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

10.2 hours before the tornado, 75 km from the path. September 11, 2023.

Skew-T log-pSkew-T log-p diagram, Jacksonville, FL at 12:00Z on 2023-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1603 joules per kilogram, CIN -25, lifted condensation level 901 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 2023-09-11The 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 8 square meters per square second, 0 to 6 km bulk shear 20 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
1603 J/kg
Mixed-layer CIN
-25 J/kg
Surface CAPE
1365 J/kg
Mixed-layer LCL
901 m above ground
0-6 km bulk shear
20 kt
0-1 km bulk shear
3 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
40 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

Jacksonville, FL (KJAX), 00:00Z

1.8 hours after it, 75 km from the path. September 12, 2023.

Skew-T log-pSkew-T log-p diagram, Jacksonville, FL at 00:00Z on 2023-09-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1037 joules per kilogram, CIN -64, lifted condensation level 1019 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 2023-09-12The 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 -65 square meters per square second, 0 to 6 km bulk shear 33 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
1037 J/kg
Mixed-layer CIN
-64 J/kg
Surface CAPE
1039 J/kg
Mixed-layer LCL
1019 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
-65 m²/s²
0-3 km storm-relative helicity
-33 m²/s²
Significant tornado parameter
-0.1
Supercell composite
-1.6
0-3 km lapse rate
4.8 K/km

Open this sounding in Storm Lab

The surface observations

St Augustine Airpt (SGJ), 20 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
20:10 UTC100° 11 kt1016.3BR
20:15 UTC90° 11 kt1016.3BR
20:20 UTC90° 13 kt1016.3BR
20:25 UTC100° 13 kt1016.3BR
20:30 UTC100° 13 kt1016.3BR
20:35 UTC100° 11 kt1016.3BR
20:40 UTC110° 11 kt1016.3BR
20:45 UTC110° 13 kt1016.3BR
20:50 UTC100° 10 kt1016.6BR
20:55 UTC100° 11 kt1016.3BR
20:56 UTC8576100° 12 kt1016.3VCTS BR
21:00 UTC100° 11 kt1016.3BR
21:05 UTC90° 13 kt1016.3BR
21:10 UTC90° 14 kt1016.3BR
21:15 UTC80° 13 kt1016.6BR
21:20 UTC80° 11 kt1016.6BR
21:25 UTC70° 11 kt1017.3BR
21:30 UTC70° 11 kt1017.3BR
21:35 UTC60° 11 kt1016.9+RA BR
21:40 UTC60° 11 kt1016.9RA BR
21:45 UTC50° 13 kt1016.6+RA BR
21:50 UTC60° 10 kt1016.6+RA BR
21:55 UTC70° 10 kt1016.9+RA BR
21:56 UTC827770° 10 kt1016.9VCTS +RA BR
22:00 UTC70° 9 kt1017.3+RA BR
22:05 UTC90° 9 kt1016.9+RA BR
22:10 UTC110° 7 kt1017.3+RA BR
22:15 UTC100° 5 kt1017.3+RA BR
22:20 UTC90° 4 kt1017.3RA BR
22:25 UTC80° 4 kt1017.3+RA BR
22:30 UTC110° 2 kt1017.6RA BR
22:35 UTC150° 2 kt1017.6+RA BR
22:40 UTC260° 5 kt1018.3RA BR
22:45 UTC270° 8 kt1018.3RA BR
22:50 UTC280° 8 kt1018.3-RA BR
22:55 UTC280° 7 kt1017.9RA BR
22:56 UTC7978280° 8 kt1017.9VCTS RA BR
23:00 UTC270° 7 kt1017.9RA BR
23:05 UTC270° 8 kt1017.9-RA BR
23:10 UTC240° 8 kt1017.9RA
23:14 UTC84.277220° 7 kt1017.9TSRA
23:15 UTC210° 7 kt1017.6RA
23:20 UTC210° 2 kt1017.6RA
23:25 UTC340° 2 kt1017.3RA
23:30 UTC0° 0 kt1017.6RA
23:35 UTC190° 2 kt1017.6RA
23:40 UTC130° 5 kt1017.6RA
23:45 UTC130° 7 kt1017.3RA
23:50 UTC170° 4 kt1017.6RA
23:55 UTC140° 5 kt1017.3RA
23:56 UTC8477140° 5 kt1016.9TSRA
00:00 UTC0° 0 kt1016.9RA
00:03 UTC78.8770° 0 kt1016.9TSRA
00:05 UTC0° 0 kt1017.3RA

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

The radar

The Jacksonville radar (KJAX), 73 km away, was scanning. The volume nearest the touchdown began at 22:11 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
20:25 UTCTSTM WND DMG1 Nw OrtegaDuval, FLCorrects previous tstm wnd dmg report from 1 NW Ortega. Report of roof blown off. Location at intersection of Blanding Blvd and Shirley Avenue.
20:25 UTCTSTM WND DMG1 Nw OrtegaDuval, FLReport of roof blown off.
20:30 UTCTSTM WND DMG1 Sw OrtegaDuval, FLReport of Large Tree Down across vehicle on Lofty Pine Circle in Ortega.
20:30 UTCTSTM WND DMG2 Sse OrtegaDuval, FLAdds hard top of gazebo blown off to previous tstm wnd dmg report from 2 SSE Ortega. Report of a tree down off Roosevelt Blvd near Timuquana Rd. Time estimated from radar.
20:30 UTCTSTM WND DMG2 Sse OrtegaDuval, FLReport of a tree down off Roosevelt Blvd near Timuquana Rd. Time estimated from radar.
20:31 UTCTSTM WND GST 614 Ne Orange ParkDuval, FLAWOS station KNIP Jacksonville Nas.
20:31 UTCTSTM WND GST 614 Ne Orange ParkDuval, FLAWOS station KNIP Jacksonville Nas.
20:40 UTCTSTM WND DMG5 Sse San MarcoDuval, FLUpdates previous tstm wnd dmg report from 5 SSE San Marco. Reports of several trees down near St. Augustine Rd near San Jose, some blocking the road. Time estimated from radar. Extensive damage to the San Jose Catholic S
20:40 UTCTSTM WND DMG5 Sse San MarcoDuval, FLReports of several trees down near St. Augustine Rd near San Jose, some blocking the road. Time estimated from radar.
21:47 UTCTSTM WND DMG3 S BakersvilleSt. Johns, FLTrees snapped and fell on 13A north of Molasses Junction. Time estimated by radar.
21:55 UTCTSTM WND DMG4 S BakersvilleSt. Johns, FLPhotos from social media shows Barn Roof Damage, Porta Potty blown over over...time base off Radar Estimate.
22:05 UTCHAIL 0.884 S BakersvilleSt. Johns, FLReport of Nickle Size Hail.
22:10 UTCTSTM WND DMG4 S BakersvilleSt. Johns, FLCorrects previous tstm wnd dmg report from 4 S Bakersville. Photos from social media shows Barn Roof Damage, Porta Potty blown over over...updated time based off Radar Estimate.
22:50 UTCTSTM WND DMGWelakaPutnam, FLTrees Reported Down at intersection of Elm Street and 11th Ave.
22:55 UTCTSTM WND DMG1 N San MateoPutnam, FLPower Lines Down at 477 S Hwy 17.
22:57 UTCTSTM WND DMG4 Ne San MateoPutnam, FLTrees Reported Down caused by thunderstorm winds.
22:58 UTCTSTM WND DMG1 S PalatkaPutnam, FLCorrects previous tstm wnd dmg report from 1 S Palatka. Powerline Down. Location 1506 Husfon Ave.
22:58 UTCTSTM WND GST 402 Ese Lake ComoPutnam, FLEstimated gusts around 40 mph. Pea size hail was also reported.
23:00 UTCTSTM WND GST 514 Sse SpudsSt. Johns, FLFAWN observation site in Hastings, FL measured a gust of 51 mph at 7 PM.
23:37 UTCTSTM WND GST 425 Se Crescent CityPutnam, FLMesonet station EW6604 Crescent City.

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

This ground now

The live radar over the trackEvery 2023 tornado in FloridaEvery tornado in Florida since 1950Warnings in force in Florida nowThe forecast where you are

The other tornadoes of September 11, 2023

1 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
September 112:55 PM EDTEF0Sussex, DE0.7370

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.