Alert archive / Texas / Severe Thunderstorm Warnings in 2004

Severe Thunderstorm Warning 177, NWS Houston/Galveston, TX

August 11, 2004Brazoria County, Matagorda County, Texas

NWS Houston/Galveston, TX issued this severe thunderstorm warning at Aug 11, 2004, 7:55 PM CDT for Brazoria County, Matagorda County, Texas. It was in force for 65 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 11, 2004, 7:55 PM CDT (00:55 UTC)
Expired
Aug 11, 2004, 9:00 PM CDT
In force
65 min
Issued by
NWS Houston/Galveston, TX
Area
Counties, with a storm outline in the text

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 00:56 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.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 0.9 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 2004-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2080 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 00:00Z on 2004-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 square meters per square second.1939Sfc1 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
2080 J/kg
Mixed-layer CIN
-22 J/kg
Mixed-layer LCL
1197 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
68 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.4

Open this sounding in Storm Lab

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 Houston/Galveston, TX wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 11, 2:25 PM CDT, 5 hours 30 minutes earlier.

Area forecast discussion, Aug 11, 2:25 PM CDT, 5 hours 30 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
225 PM CDT WED AUG 11 2004

DISCUSSION...
COLD FRONT IS APPROACHING THE OUTFLOW BOUNDARY NW OF
THE AREA AND SCT STRONG/SVR TSTMS ARE THE RESULT. WE
EXPECT SHWRS AND TSTMS TO BECOME MORE NUMEROUS ALONG THE
BOUNDARY AS THE AFTERNOON PROGRESSES. WE ALSO EXPECT SCT
SHWRS AND TSTMS TO CONTINUE TO DEVELOP ALONG THE SEA
BREEZE.

MAIN ISSUE IS PRECIP COVERAGE AND SVR TSTM POTENTIAL THIS
EVENING ACROSS SE TX. BEST CHC APPEARS TO BE ACROSS
THE NW ZONES AS THE BOUNDARY WILL BE IN THIS ZONE LATE
THIS AFT/EARLY EVE WITH HEATING STILL OCCURRING. PRECIP
COVERAGE BECOMES MORE QUESTIONABLE FURTHER SOUTH AS
BOUNDARY MOVES THROUGH LATER IN THE EVENING. HOWEVER...BASED
ON THE SOUTHEAST FLOW THAT IS DEVELOPING AHEAD OF THE
BOUNDARY OVER SE TX...THINK THAT THE LOW-LEVEL CONVERGENCE
WILL BE SUFFICIENT FOR CONTINUED TSTM DEVELOPMENT. WILL
RAISE POPS TO LIKELY AREAWIDE TONIGHT. WILL MAINTAIN SVR
TSTM POSSIBILITY...WITH THE MAIN THREATS DAMAGING WINDS
AND LARGE HAIL.

WILL DROP POPS TOMORROW WITH VERY DRY AIR PUSHING IN
BEHIND THE FRONT. THIS UNSEASONABLY COOL AIRMASS WILL BE
QUITE A CHANGE FOR THIS TIME OF YEAR. IN FACT...AM
FORECASTING AT OR BELOW RECORD LOWS FOR INLAND LOCATIONS
ON SAT MORNING.

FOR THE MARINE AREA...WE EXPECT WINDS TO INCREASE TO CAUTION
LEVELS ON THU BEHIND THE FRONT DUE TO THE RELATIVELY COOL AIR
OVER WARM WATER AND THE TIGHTENING PRESSURE GRADIENT.
&&

.HGX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 68 88 63 88 61/ 70 00 00 00
HOUSTON(IAH)          70 89 64 88 63/ 60 05 00 00
GALVESTON (GLS)       76 87 72 86 72/ 60 10 00 00
&&

33/43
Hazardous weather outlook, Aug 11, 10:47 AM CDT, 9 hours 8 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1047 AM CDT WED AUG 11 2004

TXZ163-164-176>179-195>200-210>214-226-227-235>238-121200-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-GALVESTON-
GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-MONTGOMERY-
POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-WHARTON-
1047 AM CDT WED AUG 11 2004

...SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NORTHWEST AREAS THIS
AFTERNOON AND ACROSS ALL OF SOUTHEAST TEXAS THIS EVENING...

.DAY ONE...TODAY AND TONIGHT.
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG A COOL FRONT
NORTHWEST OF SOUTHEAST THIS AFTERNOON. AS THE FRONT MOVES
SOUTHEAST...THUNDERSTORMS ARE EXPECTED TO MOVE INTO NORTHWEST PORTIONS
OF THE AREA. BECAUSE THERE IS A LAYER OF DRY AIR ABOVE A LOW-
LEVEL MOIST LAYER IN THE ATMOSPHERE...STRONG AND DAMAGING WINDS WILL
BE A POSSIBILITY WITH ANY STRONG THUNDERSTORMS THAT DEVELOP. AS THE
FRONT MOVES SOUTH THIS EVENING...THE SEVERE THUNDERSTORM THREAT WILL
ALSO SHIFT SOUTH...AND THEREFORE INCLUDE ALL OF SOUTHEAST TEXAS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.
NO HAZARDOUS WEATHER IS EXPECTED.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE NEEDED LATE THIS AFTERNOON MAINLY FOR THE
AREA ALONG AND NORTH OF A BRENHAM...HUNTSVILLE...GROVETON LINE.
SPOTTER ACTIVATION MAY BE NEEDED ACROSS ALL OF SOUTHEAST TEXAS
TONIGHT.

In the hours before

Local storm report, Aug 11, 5:35 PM CDT, 2 hours 20 minutes before
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Local storm report, Aug 11, 5:57 PM CDT, 1 hour 58 minutes before
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Local storm report, Aug 11, 6:53 PM CDT, 1 hour 2 minutes before
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    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 7:20 PM CDTSevere Thunderstorm WarningHGXFort Bend, Wharton55 min
Aug 11, 7:30 PM CDTSevere Thunderstorm WarningHGXJackson60 min
Aug 11, 7:55 PM CDTSpecial Marine WarningHGX2 hr
Aug 11, 8:31 PM CDTSevere Thunderstorm WarningHGXJackson29 min

Nearby

Severe Thunderstorm Warnings in Texas, 2004Every severe thunderstorm warning in 2004

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.