Alert archive / Texas / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 120, NWS Austin/San Antonio, TX

December 12, 2002DeWitt County, Gonzales County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Dec 12, 2002, 6:58 AM CST for DeWitt County, Gonzales County, Texas. It was in force for 62 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Dec 12, 2002, 6:58 AM CST (12:58 UTC)
Expired
Dec 12, 2002, 8:00 AM CST
In force
62 min
Issued by
NWS Austin/San Antonio, TX
Area
Counties, with a storm outline in the text

Counties DeWitt County, TX, Gonzales County, TX

The radar

The Austin/San Antonio radar (KEWX), 76 km from the middle of the area, began a volume at 13:01 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 12:00Z, 1.0 hours before the alert went out and 169 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 12:00Z on 2002-12-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 308 joules per kilogram.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.
HodographHodograph, Corpus Christi, TX at 12:00Z on 2002-12-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 198 square meters per square second.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.
Mixed-layer CAPE
308 J/kg
Mixed-layer CIN
-416 J/kg
Mixed-layer LCL
551 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
198 m²/s²
0-3 km storm-relative helicity
337 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS54 KEWX 121258
SVRSAT
TXC123-177-121400-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
658 AM CST THU DEC 12 2002

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR THE FOLLOWING COUNTIES IN TEXAS...
  GONZALES
  DEWITT

* UNTIL 800 AM CST

* AT 658 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 34 MILES SOUTH OF GONZALES...OR ABOUT 10 MILES
  SOUTHWEST OF CUERO...MOVING NORTH AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE...
  OVER GONZALES AT 755 AM

IF SEVERE WEATHER APPROACHES YOUR AREA...GO INSIDE A STURDY SHELTER
AWAY FROM CREEK BEDS AND OTHER FLOOD-PRONE AREAS. REMEMBER...A SEVERE
THUNDERSTORM CAN PRODUCE LARGE DAMAGING HAIL...DAMAGING WINDS IN
EXCESS OF 55 MPH...DEADLY LIGHTNING...AND VERY HEAVY RAIN.


LAT...LON 2898 9753 2898 9732 2964 9729 2964 9760

$$

What forecasters said that day

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

NWS Austin/San Antonio, TX wrote its last area forecast discussion before this severe thunderstorm warning went out at Dec 12, 2:30 AM CST, 4 hours 28 minutes earlier.

Area forecast discussion, Dec 12, 2:30 AM CST, 4 hours 28 minutes before
SOUTH CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
230 AM CST THU DEC 12 2002

MILD PERIOD THIS WEEK...NEAR NORMAL...WITH SYSTEMS TREKKING ACROSS
MID CONTINENT AT A DECENT PACE.  CONVECTION TODAY ENDING BY MID DAY
WEST AND CENTRAL MAY LINGER INTO THE AFTERNOON SOUTHEAST ZONES
FLIRTING WITH SEVERE LEVELS DEPENDENT ON DEGREE OF INSTABILITY THAT
DEVELOPS ALONG WARM FRONT.  WINDS WILL COME NORTHEAST IN RESPONSE TO
DEVELOPING SURFACE LOW AND EXPECT THIS TO LIMIT DESTABILIZATION
ENOUGH TO SUPPRESS ALL BUT THE MOST ISOLATED ACTIVITY ALONG EASTERN
EDGE OF THE CWA AND WILL NOT MENTION SEVERE IN FORECAST.  PROLONGED
PERIOD OF NORTHWEST FLOW WILL DRY MID AND LOWER LEVELS ALLOWING NICE
WARM UP BEHIND FRONT FRIDAY AND INTO THE WEEKEND.  TRANSITION TO
ZONAL FLOW WILL ALLOW WEAK SOUTHERLY SURFACE FLOW TO DEVELOP ON
SUNDAY ALTHOUGH GULF REMAINS SHUT OFF BELOW 850MB WELL INTO THE
EXTENDED PERIOD.  CLOUD COVER COMING AT MID AND HIGH LEVELS AS UPPER
TROF APPROACHES SUNDAY NIGHT. SLIGHT CHANCE OF SHOWERS POSSIBLE WITH
PASSAGE OF UPPER TROF ON MONDAY.  MOISTURE AND LIFT WITH STRONG MID
LEVEL JET SUFFICIENT TO SUPPORT DEEP CONVECTION WEDNESDAY INTO
THURSDAY AHEAD OF NEXT FRONT.

WRAP AROUND CLOUDS SHOULD REMAIN INTACT OVER CENTRAL AND EASTERN
ZONES TODAY KEEPING TEMPS ONCE MORE ON THE COOL SIDE.  ALTHOUGH
CLOUDS PULL OUT COLD AIR ADVECTION KEEPING WINDS UP OVERNIGHT
PREVENTING TEMPS FROM DROPPING BELOW MID 30S TO LOWER 40S AS
CURRENTLY INDICATED.

PRELIMINARY NUMBERS:

AUS 063 038/067 035 3000
DRT 068 038/069 037 3000
SAT 065 040/068 039 3000

.EWX...NONE.
10/06/KW
Hazardous weather outlook, Dec 12, 5:25 AM CST, 1 hour 33 minutes before
TXZ171>173-183>194-202>209-217>225-228-131200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
525 AM CST THU DEC 12 2002

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH CENTRAL TEXAS.

.DAY ONE...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS
MORNING FOR THE EXTREME SOUTHEAST PORTION OF SOUTH CENTRAL TEXAS.
THIS COVERS DEWITT AND LAVACA COUNTIES. THESE THUNDERSTORMS WILL
HAVE THE POTENTIAL TO PRODUCE LARGE HAIL, DAMAGING WINDS AND BRIEF
HEAVY RAINFALL OF 1 TO 3 INCHES.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE REQUIRED THIS MORNING OVER THE COASTAL
PRAIRIES OF SOUTH CENTRAL TEXAS.  A DEVELOPING STORM SYSTEM NEAR THE
COASTAL BEND WILL PRODUCE SCATTERED SEVERE THUNDERSTORMS THIS
MORNING.

.DAYS TWO THROUGH SEVEN...
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

Nearby

Severe Thunderstorm Warnings in Texas, 2002Every severe thunderstorm warning in 2002

Sources

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