Tornadoes · United States · Florida · 2017

EF0 tornado, Marineland, Florida, September 10, 2017

This EF0 tornado ran 4.1 miles across Flagler County on September 10, 2017, touching down at 8:13 PM EDT and reaching 200 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
September 10, 2017
Touchdown
8:13 PM EDT (00:13 UTC)
Lifted
8:23 PM EDT (00:23 UTC)
On the ground
10 minutes
Path length
4.1 miles (6.6 km)
Path width
200 yards (183 m)
Deaths
0
Injuries
0
County
Flagler County
Touchdown point
29.645, -81.210
Lift-off point
29.660, -81.277
Record number
1709101813-01

The damage survey

13 damage points were recorded along this path by NWS JAX, in the Damage Assessment Toolkit the survey teams carry. The highest wind the damage implies is 62 mph.

  • 24 inches above ground level. Anastasia Island, St. Aug. 235 Coquina.
  • 18 inches above ground level in garage. Matthew was 26 inches above ground.
  • 508 N. Flagler. 1 foot 6.5 inches built in 1965
  • wind damage - roof Flagler Beach Library

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

What the Weather Service recorded

Hurricane Irma's eye passed west of the local forecast area, with the region on the storm's turbulent east side. Widespread tropical storm force winds with gusts to hurricane force were felt across much of the area, with the strongest winds surging up the Florida east coast during the pre-dawn hours of Sept. 11th. Extensive tree and power line damage occurred across the local area from the winds. One of the greatest local impacts exacerbated by Irma's rainfall and storm surge was river flooding. Prior to Irma's arrival, a local nor'eastern developed 3 days prior, with strong onshore flow pumping water into the St. Johns River basin. Elevated water levels of 1-2 ft above normal tidal departure were already ongoing for several tidal cycles before Irma's surge and rainfall. The nor'easter also brought localized heavy rainfall bands, with some areas near the coast realizing 4-6 inches in 24 hrs the days prior to Irma. In addition, precursor conditions to the nor'easter included an above average rainfall across the region during the summer months. Major, historic river flooding was forecast along Black Creek and the Sante Fe a week prior to Irma. Realized river values along the St. Johns surpassed prior record levels set by Hurricane Dora in 1964, during low tide the morning of Sept. 11th. The St. Johns River basin continued to rise with the combination of trapped tides due to the nor'easter, astronomically high tides heading into the spring tide season, storm surge of up to 5 ft in some areas, fresh water rainfall of 7-11 inches, and strong southerly winds pushing the water across the basin on the east side of Irma. Historic river flooding occurred across much of NE Florida Sept 11th through the following week as water levels were slow to funnel out of the St. Johns basin. Coastal infrastructure that was already weakened about 1 year ago due to Hurricane Matthew suffered the most damage from Irma's storm surge.

This tornado touchdown in northern Flagler county just south of Marineland. Damage was limited to trees. Structural damage was not reported. A tornado debris signature was detected along the path. The tornado remained over the Pellicer Creek Conservation Area before dissipating just west of Interstate 95.

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

The warnings

3 minutes of warning. NWS JAX issued a tornado warning for this county at 00:10 UTC, 3 minutes before the tornado touched down, in force until 00:45 UTC.

The county was under a tornado watch, issued at 16:02 UTC and running to 03:50 UTC.

Issued (UTC)ExpiredProductOffice
14:12 UTC17:15 UTCFlood WarningJAX
15:57 UTC19:00 UTCFlood WarningJAX
16:02 UTC03:50 UTCTornado WatchJAX
16:19 UTC16:41 UTCTornado WarningJAX
17:28 UTC18:00 UTCTornado WarningJAX
19:09 UTC22:15 UTCFlood WarningJAX
21:21 UTC00:15 UTCFlood WarningJAX
21:48 UTC00:45 UTCFlood WarningJAX
23:36 UTC00:00 UTCTornado WarningJAX
00:09 UTC03:15 UTCFlood WarningJAX
00:10 UTC00:45 UTCTornado WarningJAX
03:50 UTC12:00 UTCTornado WatchJAX
04:26 UTC07:30 UTCFlood WarningJAX
04:49 UTC09:45 UTCFlash Flood WarningJAX
05:35 UTC08:30 UTCFlash Flood WarningJAX
12:08 UTC20:53 UTCTropical Storm 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 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), 00:00Z

0.2 hours before the tornado, 104 km from the path. September 11, 2017.

Skew-T log-pSkew-T log-p diagram, Jacksonville, FL at 00:00Z on 2017-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 270 joules per kilogram, CIN 0, lifted condensation level 514 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 00:00Z on 2017-09-11The 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 282 square meters per square second, 0 to 6 km bulk shear 39 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
270 J/kg
Mixed-layer CIN
0 J/kg
Surface CAPE
474 J/kg
Mixed-layer LCL
514 m above ground
0-6 km bulk shear
39 kt
0-1 km bulk shear
42 kt
0-1 km storm-relative helicity
282 m²/s²
0-3 km storm-relative helicity
319 m²/s²
Significant tornado parameter
0.4
Supercell composite
2.9
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

The radar

The Jacksonville radar (KJAX), 102 km away, was scanning. The volume nearest the touchdown began at 00:14 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
21:37 UTCTROPICAL STORM3 Wnw Vilano BeachSt. Johns, FLASOS MEASURED WIND GUST OF 55 MPH.
22:30 UTCTROPICAL STORM1 Nne Flagler BeachFlagler, FLSTORM SPOTTER WITH FIXED ANEMOMETER MEASURED A WIND GUST OF 50 MPH.
23:40 UTCNON-TSTM WND GST 502 Nw St. AugustineSt. Johns, FLMESONET STATION MEASURED SUSTAINED OF 30 MPH FROM THE NNE WITH A GUST OF 50 MPH.
23:50 UTCTORNADO1 N Vilano BeachSt. Johns, FLTHIS TORNADO TOUCHED DOWN ON VILLANO BEACH NEAR 4TH AND 5TH STREET CAUSING MINOR TREE DAMAGE AS IT MOVED WEST. AFTER CROSSING THE INTER-COASTAL WATERWAY THE TORNADO INTENSIFIED TO EF-1 WITH 85-100MPH WINDS AND SNAPPED/UP
23:52 UTCTORNADO4 N St. AugustineSt. Johns, FLMEDIA PASSED ON REPORT BY PUBLIC OF POSSIBLE TORNADO AT VILANO BEACH AT 4TH STREET.
23:53 UTCTORNADO4 Nnw St. AugustineSt. Johns, FLMULTIPLE TREES AND POWER LINES DOWN. ROOF DAMAGE ON 5TH AVENUE NEAR VILLANO BEACH.
00:00 UTCTSTM WND DMG2 Wnw Vilano BeachSt. Johns, FLPUBLIC REPORT OF WIND DAMAGE. TORNADO REPORT EAST OF THIS LOCATION SO POTENTIALLY MORE TORNADO DAMAGE.
00:20 UTCTORNADO1 Sse MarinelandFlagler, FLTHIS TORNADO TOUCHED DOWN IN NORTHERN FLAGLER COUNTY JUST SOUTH OF MARINELAND. DAMAGE WAS LIMITED TO TREES WITH A TORNADIC DEBRIS SIGNATURE NOTED ON KJAX RADAR. THE TORNADO REMAINED OVER THE PELLICER CREEK CONSERVATION A
00:46 UTCTROPICAL STORM5 Nnw St. AugustineSt. Johns, FLAWOS STATION MEASURED A WIND GUST OF 58 MPH.
01:05 UTCTROPICAL STORMFlagler BeachFlagler, FLTRAINED SPOTTER REPORTED A WIND GUST OF 60 MPH.
01:40 UTCFLOOD5 Se AndalusiaFlagler, FLA NUMBER OF SECONDARY ROADS IN THE DAYTONA NORTH AREA ARE IMPASSABLE.
02:02 UTCHURRICANEDaytona Beach AirportVolusia, FLASOS AT DAYTONA BEACH INT. AIRPORT MEASURED A PEAK WIND GUST OF 78MPH/68KT FROM THE NORTHEAST.
02:55 UTCTROPICAL STORMBunnellFlagler, FLFIN ASOS REPORTED A GUST OF 51 KNOTS.

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

The other tornadoes of September 10, 2017

15 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
September 108:59 AM EDTEF1Hardee, FL0.050$40,000
September 109:19 AM EDTEF0Brevard, FL0.250
September 1011:00 AM EDTEF1Brevard, FL1.375
September 1011:19 AM EDTEF2Polk, FL0.650$20,000
September 1011:24 AM EDTEF1Brevard, FL1.275
September 101:40 PM EDTEF1Saint Johns, FL1.250
September 105:48 PM EDTEF2Brevard, FL1.6125
September 106:00 PM EDTEF1Brevard, FL0.560
September 106:28 PM EDTEF1Lake, FL3.8500
September 107:50 PM EDTEF1Saint Johns, FL5.0200
September 109:04 PM EDTEF1Volusia, FL0.8175
September 109:04 PM EDTEF1Brevard, FL1.250
September 109:14 PM EDTEF1Brevard, FL0.360
September 109:48 PM EDTEF1Brevard, FL3.460
September 101:15 AM EDTEF2Saint Johns, FL1.2300

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.