Tornadoes · United States · Texas · 1999

F0 tornado, Tarzan, Texas, May 1, 1999

This F0 tornado ran 0.1 miles across Martin County on May 1, 1999, touching down at 5:36 PM CDT and reaching 80 yards wide. It killed nobody.

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
May 1, 1999
Touchdown
5:36 PM CDT (22:36 UTC)
Path length
0.1 miles (0.2 km)
Path width
80 yards (73 m)
Deaths
0
Injuries
0
County
Martin County
Touchdown point
32.300, -102.170
Lift-off point
32.300, -102.170
Record number
1030

What the Weather Service recorded

The cell that had produced the tornado in Ector County, dissipated, but its associated cluster began to favor one cell and by the time the cluster was in Eastern Andrews County it was forming into an HP supercell. Just after crossing into Martin County the storm produced a very brief tornado. The storm had a huge slot of rain that had wrapped around the mesocyclone. The spotter who saw the tornado was in heavy rain to the southeast of the spinup point. Video showed the condensation funnel to the ground, but rotation looked fairly weak. The unfavorable environment quickly destroyed the tornado within about one minute.

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

The warnings

0 minutes of warning. NWS MAF issued a tornado warning for this county at 22:36 UTC, 0 minutes before the tornado touched down, in force until 23:00 UTC.

Issued (UTC)ExpiredProductOffice
22:36 UTC23:00 UTCTornado WarningMAF
22:56 UTC23:30 UTCTornado WarningMAF
23:30 UTC00:00 UTCTornado WarningMAF

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 19:26 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.

Midland Regional, TX (KMAF), 12:00Z

10.6 hours before the tornado, 39 km from the path. May 1, 1999.

Skew-T log-pSkew-T log-p diagram, Midland Regional, TX at 12:00Z on 1999-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 199 joules per kilogram, CIN -28, lifted condensation level 536 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, Midland Regional, TX at 12:00Z on 1999-05-01The 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 317 square meters per square second, 0 to 6 km bulk shear 66 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
199 J/kg
Mixed-layer CIN
-28 J/kg
Surface CAPE
89 J/kg
Mixed-layer LCL
536 m above ground
0-6 km bulk shear
66 kt
0-1 km bulk shear
31 kt
0-1 km storm-relative helicity
317 m²/s²
0-3 km storm-relative helicity
505 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.3
0-3 km lapse rate
5.1 K/km

Open this sounding in Storm Lab

Midland Regional, TX (KMAF), 00:00Z

1.4 hours after it, 39 km from the path. May 2, 1999.

Skew-T log-pSkew-T log-p diagram, Midland Regional, TX at 00:00Z on 1999-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 844 joules per kilogram, CIN -88, lifted condensation level 804 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, Midland Regional, TX at 00:00Z on 1999-05-02The 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 143 square meters per square second, 0 to 6 km bulk shear 52 knots.1939587897Sfc1 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
844 J/kg
Mixed-layer CIN
-88 J/kg
Surface CAPE
1692 J/kg
Mixed-layer LCL
804 m above ground
0-6 km bulk shear
52 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
143 m²/s²
0-3 km storm-relative helicity
232 m²/s²
Significant tornado parameter
0.7
Supercell composite
5.8
0-3 km lapse rate
7.0 K/km

Open this sounding in Storm Lab

The radar

The Midland/Odessa radar (KMAF), 40 km away, was scanning. The volume nearest the touchdown began at 22:37 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 1999 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of May 1, 1999

8 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 13:46 PM CDTF0Ector, TX0.7100
May 14:37 PM CDTF1Gaines, TX2.5120$10,000
May 16:09 PM CDTF0Castro, TX0.1100
May 16:18 PM CDTF0Castro, TX0.130
May 18:07 PM CDTF0Hartley, TX0.150
May 18:42 PM CDTF0Lamb, TX0.130
May 18:43 PM CDTF0Lamb, TX0.130
May 18:43 PM CDTF0Hale, TX0.230

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.