Alert archive / Texas / Tornado Warnings in 2001

Tornado Warning 37, NWS Houston/Galveston, TX

December 12, 2001Brazoria County, Matagorda County, Texas

NWS Houston/Galveston, TX issued this tornado warning at Dec 12, 2001, 1:59 AM CST for Brazoria County, Matagorda County, Texas. It was in force for 46 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Dec 12, 2001, 1:59 AM CST (07:59 UTC)
Expired
Dec 12, 2001, 2:45 AM CST
In force
46 min
Issued by
NWS Houston/Galveston, TX
Area
Whole counties

Counties Brazoria County, TX, Matagorda County, TX

The radar

The Houston radar (KHGX), 83 km from the middle of the area, began a volume at 08:02 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Dec 12, 2:20 AM CSTTornado F1Brazoria, TXAn F1 Tornado touched down 5 miles southwest of Brazoria. Several homes in the Lazy Oak Ranch Subdivision on CR 461A had roof damage. A machine shop on CR 461 sustained heavy damage, along with the cars and boats in its parking lot. There were no injuries. N
Dec 12, 2:30 AM CSTTornado F0Brazoria, TXAn F0 Tornado touched down in the city of Brazoria. There was roof and structural damage to homes and businesses, in a 10 block area, along TX Highway 36 in Brazoria. A 175 foot internet tower was blown down, signs were bent over, and minor roof damage to Bra

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 8.0 hours before the alert went out and 211 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Corpus Christi, TX at 00:00Z on 2001-12-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 73 joules per kilogram.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.
HodographHodograph, Corpus Christi, TX at 00:00Z on 2001-12-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 168 square meters per square second.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.
Mixed-layer CAPE
73 J/kg
Mixed-layer CIN
-123 J/kg
Mixed-layer LCL
709 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
168 m²/s²
0-3 km storm-relative helicity
188 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

What forecasters said that day

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

NWS Houston/Galveston, TX wrote its last area forecast discussion before this tornado warning went out at Dec 11, 9:00 PM CST, 4 hours 59 minutes earlier.

Area forecast discussion, Dec 11, 9:00 PM CST, 4 hours 59 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
900 PM CST TUE DEC 11 2001

KHGX SHOWS EXTENSIVE SHRA/TSRA ACROSS THE CWA AT MID EVENING.
REGIONAL 88DS SHOW WIDESPREAD COVERAGE TO THE NE...WITH ISOLD TO SCT
COVERAGE OVER SCNTRL TX AND THE LOWER COAST. SFC OBS INDICATE THE
WARM FRONT ROUGHLY ALONG I-10 ATTM...WITH SRLY WINDS TO THE SOUTH
AND ERLY WINDS TO THE NORTH. THE MAIN UPDATE ISSUES ARE POPS/TEMPS
TONIGHT...AND SEVERE/HEAVY RAIN THREAT FOR WED.

THE CURRENT POP TREND WILL BE DOWN FOR THE NEXT 6 HRS...THEN PICK UP
AGAIN TOWARD MORNING AS A 100-115 KT 300 MB JET STREAK AND
ASSOCIATED SHORT WAVE TROUGH ROUND THE LONGWAVE TROUGH BASE AND
EJECT OVER TX. WILL UPDATE TO REWORD THE FORECAST AS SUCH...
REFOCUSING POPS TOWARD MORNING...BUT GENERALLY KEEPING THEM
CATEGORICAL.

THE OTHER ISSUES ARE SEVERE/HEAVY RAIN THREAT. 18-24Z WED MODEL
SOUNDINGS CONTINUE TO SHOW MUCAPE OF 1250-2250 J/KG...0-6 KM SHEAR
OF 20 M/S...0-3 KM SRH OF 150-250 M2/S2...AND DRY AIR/STEEP LAPSE
RATES FROM 500-700 MB. WV IMAGERY TRENDS AND 00Z CRP/BRO SOUNDINGS
INDICATE THE LIKELIHOOD FOR THESE CONDITIONS OVER OUR AREA ON TUE.
WILL TAKE THE UNUSUAL STEP OF ISSUING A HEAVY RAIN/SEVERE WEATHER
OUTLOOK FOR THE SECOND PERIOD...FIGURING FOLKS WOULD RATHER KNOW
TONIGHT THAN TOMORROW MORNING. WILL UPDATE THE ZONE FORECASTS
ACCORDINGLY. PRIND ARE THE MAIN THREAT TO BE ALONG/SOUTH OF A LINE
FROM CLL TO CXO TO LIBERTY.

.HGX...SCEC FOR BAYS AND GULF WATERS OUT 0-60NM.

31/40/48

UPDATE PRELIMS...
CLL TB 060/070 048/058 043 +64  RISING TEMPS TO 7 AM VALUE FAR LEFT
IAH TW 066/073 057/061 045 +75  DITTO
GLS TW 070/073 065/064 052 +75  DITTO

In the hours before

Special weather statement, Dec 11, 9:20 PM CST, 4 hours 39 minutes before
TXZ163-164-176>179-195>200-210>214-226-227-235>238-121030-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
920 PM CST TUE DEC 11 2001

...SLIGHT RISK OF SEVERE STORMS AND HEAVY RAIN ON WEDNESDAY...

THERE IS A SLIGHT RISK FOR SEVERE STORMS AND HEAVY RAIN ON WEDNESDAY.
THE MAIN SEVERE THREAT IS ISOLATED TORNADOES AND DAMAGING WINDS. THE
PRIMARY THREAT TIME IS FROM NOON TO 7 PM. THE MOST LIKELY THREAT
AREA IS ALONG AND SOUTH OF A LINE FROM COLLEGE STATION TO CONROE TO
LIBERTY.

SOME STORMS WILL PRODUCE HEAVY RAIN AND SOME LOCATIONS WILL
HAVE A SERIES OF STORMS MOVE OVER IN A FEW HOURS...KNOWN AS ECHO
TRAINING. HEAVY RAINFALL MAY RESULT. AVERAGE RAINFALL AMOUNTS
TONIGHT THROUGH WEDNESDAY NIGHT WILL AVERAGE 1 TO 2 INCHES...BUT A
FEW LOCATIONS COULD RECEIVE 3 TO 5 INCHES OF RAIN. THE MOST LIKELY
THREAT AREA FOR HEAVY RAIN WILL BE ALONG AND NORTH OF INTERSTATE 10.

A STRONG JET STREAK...UPPER TROUGH...AND MOIST GULF AIR WILL CAUSE
SHOWERS AND THUNDERSTORMS TO DEVELOP ON WEDNESDAY. PRESENT
INDICATIONS ARE SUNSHINE WILL PEAK THROUGH OVER SOUTHERN LOCATIONS...
PROVIDING SURFACE HEATING. VERTICAL WIND SHEAR IS SUFFICIENT TO
MAINTAIN ROTATING UPDRAFTS...AND HENCE THE THREAT FOR ISOLATED
TORNADOES...DAMAGING WINDS...AND HEAVY RAIN.

STAY TUNED TO NOAA WEATHER RADIO OR OTHER NEWS PROVIDERS FOR THE
LATEST FORECASTS...STATEMENTS...AND POSSIBLE WARNINGS ON WEDNESDAY.

31/JWZ

The office that day

Everything else NWS Houston/Galveston, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 12, 9:07 AM CSTSevere Thunderstorm WarningHGXChambers, Liberty38 min

Nearby

Tornado Warnings in Texas, 2001Every tornado warning in 2001Tornadoes in 2001

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.