F0 tornado, Conroe, Texas, December 23, 2002

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

December 23, 2002

Touchdown

1:20 PM CST (19:20 UTC)

Path length

0.5 miles (0.8 km)

Path width

20 yards (18 m)

Deaths

0

Injuries

0

Property damage

$10,000

County

Montgomery County

Touchdown point

30.270, -95.520

Lift-off point

30.270, -95.520

Record number

561

This December 23rd tornado and severe thunderstorm outbreak developed as a strong upper level low pressure system moved out of the southwestern U.S. and off to the east and northeast across the state of Texas. Abundant low level moisture was already in place across southeast Texas. Very strong shear, or turning and strengthening of the winds with height, was expected to last throughout the day. A warm front moved northward throughout the day and became a focus for the development of showers and thunderstorms. With the strong shear present, a significant number of thunderstorms quickly became severe. During an eighteen hour stretch, ten tornadoes and several large hail events were reported mainly north and west of the Houston area. Locations from the Houston area to the beaches felt the brunt of this event in the evening when a squall line rapidly moved eastward toward the coast. Three injuries and over $800,000 in damage occurred with this outbreak.

Tornado spotted near FM 1488 and Highway 242.

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

6 minutes of warning. NWS HGX issued a tornado warning for this county at 19:14 UTC, 6 minutes before the tornado touched down, in force until 20:00 UTC.

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 High Risk, with a 0.25 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 11:53 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.

Conroe/Montgomery County Airport (CXO), 14 km from the path, in the two hours either side.

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

The Houston radar (KHGX), 98 km away, was scanning. The volume nearest the touchdown began at 19:20 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.

The live radar over the trackEvery 2002 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

14 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.