F0 tornado, Callaghan, Texas, April 4, 2004

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.

Rating

F0

Date

April 4, 2004

Touchdown

3:04 PM CDT (20:04 UTC)

Path length

0.2 miles (0.3 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

County

Webb County

Touchdown point

28.030, -99.400

Lift-off point

28.030, -99.400

Record number

69

An upper level trough remained situated out to the west in Northern Mexico and the Southwest U.S. A very unstable airmass developed during the afternoon hours across South Texas triggering thunderstorms. An upper level shortwave rotated out of Mexico during the afternoon providing increasing large-scale ascent, divergence aloft and steepening mid-level lapse rates. Thunderstorms initially began as supercells across the Rio Grande Plains and Duval and Jim Wells counties during the afternoon and early evening, producing large hail and heavy rain. The supercells organized into a squall-line during the evening and moved east across the Coastal Bend, producing heavy rainfall and flash flooding. A wake low formed over the Coastal Bend behind the squall line as it moved into the offshore waters during the late night and early morning hours. High sustained winds of 40 to 50 mph, with some gusts over 60 mph, developed over the Coastal Bend, Victoria Crossroads region and the bays and nearshore waters. Damage associated with these winds was mainly confined to tree limbs, however a tug boat in Port Oconnor was reportedly damaged. See High Wind event entry as well as wind entries under Gulf of Mexico for further information.

Public reported a brief touchdown just off of Highway 44, 5 miles west of Interstate 35. The tornado remained over open country.

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

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

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 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 19:56 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 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.

Cotulla Municipal (COT), 51 km from the path, in the two hours either side.

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

The live radar over the trackEvery 2004 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

1 more were confirmed in the United States that day.

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.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.