Tornadoes · United States · Florida · 1997

F0 tornado, Spring Hill to Brooksville, Florida, April 23, 1997

From Spring Hill to Brooksville, this F0 tornado ran 16.0 miles across Hernando County on April 23, 1997, touching down at 9:55 AM EDT and reaching 10 yards wide. It killed nobody, and did $500,000 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. F040 to 72 mphthis tornado

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. F173 to 112 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. F2113 to 157 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. F3158 to 206 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. F4207 to 260 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. F5261 to 318 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
F0
Date
April 23, 1997
Touchdown
9:55 AM EDT (13:55 UTC)
Path length
16.0 miles (25.7 km)
Path width
10 yards (9 m)
Deaths
0
Injuries
0
Property damage
$500,000
County
Hernando County
Touchdown point
28.520, -82.430
Lift-off point
28.550, -82.180
Record number
413

What the Weather Service recorded

One of six waterspouts moved onshore and touched downed briefly without damage before it dissipated.

The second of a family of six waterspouts moved onshore and briefly touched down as tornado without damage before it dissipated.

A tornado touched down and damaged at least twelve mobile homes and a church in Spring Hill. The most significant damage occurred on Blackhawk Drive where several mobile homes were damaged and a car was smashed by a fallen tree. The tornado downed numerous trees, power lines, broke windows and downed signs from U.S. Highway 19 east across the city of Spring Hill before it lifted. One person, standing outside near the damaged church, suffered facial and leg injuries from wind blown glass.

A tornado sporatically touched down along a 16 mile path and damaged up to 50 homes from near U.S. HIghway 41, four miles southwest of Brooksville, east to the Ridge Manor area. Several trees and power lines were also downed from the tornado before it lifted and dissipated. Most damage to homes in the path of the tornado consisted of minor to moderate roof damage, destroyed porch and pool enclosures and downed trees.

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

The warnings

25 minutes of warning. NWS TBW issued a tornado warning for this county at 13:30 UTC, 25 minutes before the tornado touched down, in force until 14:15 UTC.

Issued (UTC)ExpiredProductOffice
12:55 UTC14:00 UTCSevere Thunderstorm WarningTBW
13:30 UTC14:15 UTCTornado WarningTBW
14:10 UTC15:15 UTCSevere Thunderstorm WarningTBW

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 06:04 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.

Tampa Bay, FL (KTBW), 12:00Z

1.9 hours before the tornado, 93 km from the path. April 23, 1997.

Skew-T log-pSkew-T log-p diagram, Tampa Bay, FL at 12:00Z on 1997-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2247 joules per kilogram, CIN -1, lifted condensation level 587 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, Tampa Bay, FL at 12:00Z on 1997-04-23The 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 190 square meters per square second, 0 to 6 km bulk shear 32 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
2247 J/kg
Mixed-layer CIN
-1 J/kg
Surface CAPE
2431 J/kg
Mixed-layer LCL
587 m above ground
0-6 km bulk shear
32 kt
0-1 km bulk shear
32 kt
0-1 km storm-relative helicity
190 m²/s²
0-3 km storm-relative helicity
250 m²/s²
Significant tornado parameter
1.8
Supercell composite
9.4
0-3 km lapse rate
6.0 K/km

Open this sounding in Storm Lab

Tampa Bay, FL (KTBW), 00:00Z

10.1 hours after it, 93 km from the path. April 24, 1997.

Skew-T log-pSkew-T log-p diagram, Tampa Bay, FL at 00:00Z on 1997-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -58832, lifted condensation level 1225 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Tampa Bay, FL at 00:00Z on 1997-04-24The 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 -100 square meters per square second, 0 to 6 km bulk shear 37 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
0 J/kg
Mixed-layer CIN
-58832 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1225 m above ground
0-6 km bulk shear
37 kt
0-1 km bulk shear
30 kt
0-1 km storm-relative helicity
-100 m²/s²
0-3 km storm-relative helicity
-65 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.2 K/km

Open this sounding in Storm Lab

The surface observations

Brooksville (Asos) (BKV), 16 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
11:54 UTC7773200° 12 kt191002.7
12:54 UTC7773200° 15 kt211002.7

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

The radar

The Tampa radar (KTBW), 93 km away, was scanning. The volume nearest the touchdown began at 13:54 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 1997 tornado in FloridaEvery tornado in Florida since 1950Warnings in force in Florida nowThe forecast where you are

The other tornadoes of April 23, 1997

23 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 238:10 AM EDTF0Levy, FL1.210$20,000
April 239:10 AM EDTF0Hernando, FL0.110
April 239:10 AM EDTF0Hernando, FL0.210
April 239:30 AM EDTF0Volusia, FL0.120
April 239:30 AM EDTF0Volusia, FL0.120
April 239:35 AM EDTF0Citrus, FL1.010$110,000
April 239:40 AM EDTF0Hernando, FL1.0101$150,000
April 2310:10 AM EDTF0Sumter, FL2.310$200,000
April 2310:15 AM EDTF0Volusia, FL0.330$60,000
April 2310:15 AM EDTF0Volusia, FL0.330$60,000
April 2310:20 AM EDTF0Lake, FL0.330$150,000
April 2310:20 AM EDTF0Lake, FL0.330$150,000
April 2310:44 AM EDTF0Volusia, FL1.230$120,000
April 2310:44 AM EDTF0Volusia, FL1.230$120,000
April 2310:50 AM EDTF0Volusia, FL3.030$250,000
April 2310:50 AM EDTF0Volusia, FL3.030$250,000
April 2311:38 AM EDTF0Pinellas, FL0.110
April 2311:46 AM EDTF0Hillsborough, FL0.110$10,000
April 2312:45 PM EDTF0Manatee, FL0.110
April 231:10 PM EDTF0Manatee, FL0.110$60,000
April 233:10 PM EDTF0Sarasota, FL0.110$30,000
April 234:00 PM MSTF0Coconino, AZ1.050$2,000
April 234:38 PM MSTF0Coconino, AZ0.110

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.