Tornadoes · United States · Florida · 2020

EF0 tornado, Lake Jessup, Florida, April 20, 2020

This EF0 tornado ran 2.7 miles across Seminole County on April 20, 2020, touching down at 11:45 AM EDT and reaching 25 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
April 20, 2020
Touchdown
11:45 AM EDT (15:45 UTC)
Lifted
11:48 AM EDT (15:48 UTC)
On the ground
3 minutes
Path length
2.7 miles (4.4 km)
Path width
25 yards (23 m)
Deaths
0
Injuries
0
County
Seminole County
Touchdown point
28.719, -81.242
Lift-off point
28.719, -81.197
Record number
2004200945-01

The damage survey

2 damage points were recorded along this path by NWS MLB, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 65 mph.

  • Trained spotter and public video showing tornado on the ground south of Sanford.
  • Storm spotter reported picture of waterspout forming on Lake Jesup crossing SR 417 at 11:45 AM.

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

As a broken line of severe thunderstorms moved through Seminole County, one storm produced a brief wasterspout/tornado on and near Lake Jesup. A second thunderstorm produced damaging winds in Volusia County, while a third thunderstorm produced damaging winds and hail in Martin County.

National Weather Service Melbourne staff conducted a damage survey and found no damage along the radar-estimated rotational track of a supercell thunderstorm, which moved from Seminole County to the Brevard County coast. The survey team searched along a path from Heathrow to Scottsmoor. However, based on numerous videos received from trained spotters and the general public, NWS Melbourne confirms that a waterspout developed on Lake Jesup just east of State Road 417. The waterspout continued east for approximately 2.75 miles, and came onshore briefly as an EF-0 tornado (peak winds estimated 60-65 mph) within an unpopulated area adjacent to the lake.

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

The forecast that day

The Storm Prediction Center had this point in a Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 12:49 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.

What forecasters said that day

The local office's own words before the tornado touched down, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Melbourne, FL wrote its last area forecast discussion before the tornado touched down at Apr 20, 9:04 AM EDT, 2 hours 41 minutes earlier.

Area forecast discussion, Apr 20, 9:04 AM EDT, 2 hours 41 minutes before
East Central Florida Forecast Discussion
National Weather Service Melbourne FL
904 AM EDT Mon Apr 20 2020

.DISCUSSION...

...Severe Thunderstorm Watch for Most of Central Florida Until 3
PM...

Today...Stronger storms are poised to enter the forecast area from
the north and west over the next couple hours. Isolated severe
storms could develop, with locally damaging winds and hail possible,
along with an isolated tornado. Windy ahead of the front with a
period of time for surface heating creating some additional
instability into the afternoon.

By late morning to early afternoon rain chances increase all the way
down to the Space Coast as the main frontal boundary moves into our
area. Scattered to numerous showers possible with embedded
stronger lightning storms.

Abundant moisture with dew points in the upper 60s/low 70s and very
strong diurnal heating contribute to MLCAPE values up to 2000 J/kg.
Hodographs are mostly mostly unidirectional and straight-lined. The
biggest question mark is going to be forcing for convective
initiation as the main upper trough departs the area and the front
flattens out/weakens and slows once it reaches the I-4 corridor.

Environmental conditions are favorable for isolated severe storms,
with the main threat of damaging wind gusts, hail up to quarter
size, and deadly lightning strikes. The threat is greatest in
the watch area, from Brevard/Osceola Counties north.

A Lake Wind Advisory is in place for sustained southwest winds 20-25
mph with gusts up to 35mph into late afternoon. This also drives up
afternoon temperatures to record values in some areas.

Tonight...As previously mentioned, model guidance shows the
weakening frontal boundary slowing down between the Cape and
Treasure Coast. Scattered showers and isolated lightning storms
linger into the evening hours. Though, there is considerable
uncertainty regarding how many storms will actually materialize
due to weak convergence along the front. As the front sags south
through the overnight, isolated to scattered showers possible from
Sebastian south. Again, there is high uncertainty with this
forecast as rain chances could be much less if front fizzles by
late evening. Winds decrease to 5-10mph after sunset and veer
west/northwest. Overnight lows in the low/mid 60s, except upper
60s in Martin County.

&&

.AVIATION...
Windy today, sustained southwest winds 20 knots and gusts up to 30
knots possible through the afternoon. A cold front moves in this
morning, bringing showers and some strong lightning storms. Highest
confidence in storm impacts at KDAB/KMCO/KSFB/KISM, with possible
early afternoon storms approaching KTIX/KMLB but confidence is lower.

&&

.MARINE...
Today...Hazardous boating conditions today as a cold front
approaches the area, increasing the pressure gradient over all east
central Florida waters. This results in southwest winds 20-25 knots
with higher gusts. Seas 3-5 feet nearshore and 5-6 feet offshore.
A Small Craft Advisory remains in effect for all waters through 8
PM tonight. A few strong to severe storms possible from late
morning into the early afternoon. Main threats will be wind gusts
in excess of 40 knots, hail, and dangerous lightning strikes.

Tonight...The cold front weakens as it moves south of the Cape this
evening, winds diminish to 15-20 knots and seas drop to 3-4 feet
nearshore and 4-6 feet offshore. Small craft still need to exercise
caution tonight. Scattered showers and lingering lightning storms
possible from Sebastian Inlet south.

&&

.CLIMATE...
Record highs for April 20th at a few sites.

                    RECORD
            DATE     HIGH
Melbourne   20-APR  91 1944
Vero Beach  20-APR  90 1968
Fort Pierce 20-APR  92 1968

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...Severe thunderstorm watch for Coastal
     Volusia-Inland Volusia-Northern Brevard-
     Northern Lake-Orange-Osceola-Seminole-Southern
     Brevard-Southern Lake-until 3 PM EDT.

     Lake Wind Advisory until 8 PM EDT this evening for Coastal
     Volusia-Indian River-Inland Volusia-Martin-Northern Brevard-
     Northern Lake-Okeechobee-Orange-Osceola-Seminole-Southern
     Brevard-Southern Lake-St. Lucie.

AM...Severe thunderstorm watch Flagler
     Beach to Volusia-Brevard County Line 0-20 nm-Volusia-Brevard
     County Line to Sebastian Inlet 0-20 nm-until 3 PM EDT.
     Small Craft Advisory until 8 PM EDT this evening for Flagler
     Beach to Volusia-Brevard County Line 0-20 nm-Flagler Beach
     to Volusia-Brevard County Line 20-60 nm-Sebastian Inlet to
     Jupiter Inlet 0-20 nm-Sebastian Inlet to Jupiter Inlet 20-
     60 nm-Volusia-Brevard County Line to Sebastian Inlet 0-20
     nm-Volusia-Brevard County Line to Sebastian Inlet 20-60 nm.

&&

JP/TES/KN/MW
Hazardous weather outlook, Apr 20, 7:32 AM EDT, 4 hours 13 minutes before
Hazardous Weather Outlook
National Weather Service Melbourne FL
732 AM EDT Mon Apr 20 2020

AMZ550-552-555-570-572-575-FLZ041-044>047-053-054-058-059-064-141-
144-147-202200-
Flagler Beach to Volusia-Brevard County Line 0-20 nm-Volusia-
Brevard County Line to Sebastian Inlet 0-20 nm-
Sebastian Inlet to Jupiter Inlet 0-20 nm-Flagler Beach to Volusia-
Brevard County Line 20-60 nm-Volusia-
Brevard County Line to Sebastian Inlet 20-60 nm-
Sebastian Inlet to Jupiter Inlet 20-60 nm-Inland Volusia-
Northern Lake-Orange-Seminole-Southern Brevard-Osceola-
Indian River-Okeechobee-St. Lucie-Martin-Coastal Volusia-
Southern Lake-Northern Brevard-
732 AM EDT Mon Apr 20 2020

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL FLORIDA.

.DAY ONE...TODAY AND TONIGHT.
...SEVERE THUNDERSTORM WATCH FOR MOST OF CENTRAL FLORIDA THROUGH
3 PM...

.THUNDERSTORM IMPACT...
Numerous fast moving showers and strong lightning storms will move
eastward across east central Florida. Deadly lightning strikes
and potentially damaging wind gusts, along with a brief tornado
will be a threat within any strong to possibly severe storms
which may develop. Damaging winds up to 60 mph, and hail up to
quarter size. A brief tornado is possible within any cell which
may acquire rotation. The greatest risk for any severe storms will
be from Brevard and Osceola counties northward.

.FLOOD IMPACT...
Locally heavy rainfall of a half to one inch will be possible in
a brief period, leading to some nuisance flooding of low spots and
roadways.

.RIP CURRENT IMPACT...
There is a moderate risk of rip currents at all east central
Florida beaches today, mainly due to an increasing short period
swell. While dangerous rip currents will be present all day, the
risk will be greatest from 10 AM to 4 PM due to tidal effects.
Swim only within sight of a lifeguard. If no lifeguard is present,
don't enter the surf. Be aware that beach closures remain in
effect for some communities.

.MARINE THUNDERSTORM GUST IMPACT...
Scattered strong lightning storms will push offshore during the
day. As these storms cross the coast and nearshore waters most
will be capable of wind gusts in excess of 35 knots. If a severe
storm develops, there is a chance of wind gusts up to 50 knots.

.WATERSPOUT IMPACT...
A brief waterspout is possible within any cell which may acquire
rotation.

.WIND AND SEA IMPACT...
Southwest winds up to 20 knots over the nearshore waters, and 20
to 25 knots with higher gusts over the offshore waters. A Small
Craft Advisory is in effect for all local waters through 8 PM.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.
Drier weather is expected during mid week before a chance for
storms returns late in the week. A Moderate risk of rip currents
is expected at all east central Florida beaches through mid week.

.SPOTTER INFORMATION STATEMENT...
Spotter activation may be needed. Please relay any information about
severe weather to the NWS while following all local, state, and CDC
guidelines.

KR/JP

In the hours before

Special weather statement, Apr 20, 9:41 AM EDT, 2 hours 4 minutes before
Special Weather Statement
National Weather Service Melbourne FL
941 AM EDT Mon Apr 20 2020

FLZ041-044-141-201445-
Northern Lake County FL-Coastal Volusia FL-Inland Volusia FL-
941 AM EDT Mon Apr 20 2020

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL AND NORTH LAKE AND
VOLUSIA COUNTIES UNTIL 1045 AM EDT...

At 939 AM EDT, Doppler radar was tracking a strong
cluster of thunderstorms near Lynne, moving northeast at 60 mph.

Nickel size hail and wind gusts of 50 to 55 mph will be possible with
these storms.

Locations impacted include...
Deltona, Lake George, Deland, Daytona Beach, Port Orange, and Ormond
Beach.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional
information and possible warnings from the National Weather Service.

&&

A Severe Thunderstorm Watch remains in effect until 300 PM EDT for
east central Florida.

LAT...LON 2943 8107 2910 8093 2885 8136 2887 8135
      2888 8136 2882 8142 2878 8195 2896 8195
      2896 8166 2905 8166 2906 8164 2928 8164
      2932 8168 2938 8145 2940 8142 2926 8142
      2927 8115 2941 8116
TIME...MOT...LOC 1339Z 246DEG 63KT 2915 8196

Sedlock
Special weather statement, Apr 20, 10:32 AM EDT, 1 hour 13 minutes before
Special Weather Statement
National Weather Service Melbourne FL
1032 AM EDT Mon Apr 20 2020

FLZ041-044>046-144-201515-
Northern Lake County FL-Orange FL-Seminole FL-Inland Volusia FL-
Southern Lake County FL-
1032 AM EDT Mon Apr 20 2020

...SIGNIFICANT WEATHER ADVISORY FOR WESTERN SEMINOLE...CENTRAL AND
SOUTHERN LAKE...NORTHWESTERN ORANGE AND SOUTH CENTRAL VOLUSIA
COUNTIES UNTIL 1115 AM EDT...

At 1032 AM EDT, Doppler radar was tracking a strong thunderstorm near
Leesburg, moving east at 40 mph.

Pea size hail and wind gusts of 50 to 55 mph will be possible with
this storm.

Locations impacted include...
Orlando, Sanford, Apopka, Altamonte Springs and Ocoee.

A Severe Thunderstorm Watch remains in effect until 300 PM EDT for
east central Florida.

LAT...LON 2886 8195 2899 8132 2856 8129 2857 8195
TIME...MOT...LOC 1432Z 269DEG 34KT 2879 8196

Sedlock

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.

Cape Canaveral, FL (KXMR), 12:00Z

3.8 hours before the tornado, 75 km from the path. April 20, 2020.

Skew-T log-pSkew-T log-p diagram, Cape Canaveral, FL at 12:00Z on 2020-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2398 joules per kilogram, CIN -21, lifted condensation level 793 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, Cape Canaveral, FL at 12:00Z on 2020-04-20The 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 224 square meters per square second, 0 to 6 km bulk shear 55 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
2398 J/kg
Mixed-layer CIN
-21 J/kg
Surface CAPE
3655 J/kg
Mixed-layer LCL
793 m above ground
0-6 km bulk shear
55 kt
0-1 km bulk shear
25 kt
0-1 km storm-relative helicity
224 m²/s²
0-3 km storm-relative helicity
268 m²/s²
Significant tornado parameter
4.0
Supercell composite
18.3
0-3 km lapse rate
5.7 K/km

Open this sounding in Storm Lab

The surface observations

Sanford/Orlando (SFB), 7 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:00 UTC

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

The radar

The Melbourne radar (KMLB), 87 km away, was scanning. The volume nearest the touchdown began at 15:44 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.

This ground now

The live radar over the trackEvery 2020 tornado in FloridaEvery tornado in Florida since 1950Warnings in force in Florida nowThe forecast where you are

The other tornadoes of April 20, 2020

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 202:10 AM EDTEF2Worth, GA8.7500$350,000
April 209:35 AM EDTEF1Marion, FL0.5500
April 209:39 AM EDTEF0Citrus, FL7.335$100,000

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.