Alert archive / Texas / Flash Flood Warnings in 2002

Flash Flood Warning 41, NWS Houston/Galveston, TX

September 10, 2002Galveston County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Sep 10, 2002, 6:01 AM CDT for Galveston County, Texas. It was in force for 59 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
Sep 10, 2002, 6:01 AM CDT (11:01 UTC)
Expired
Sep 10, 2002, 7:00 AM CDT
In force
59 min
Issued by
NWS Houston/Galveston, TX
Area
Counties, with a storm outline in the text

County Galveston County, TX

The radar

The Houston radar (KHGX), 23 km from the middle of the area, began a volume at 11:03 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 flash flood 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

Lake Charles Mun, LA (KLCH), launched 00:00Z, 11.0 hours before the alert went out and 192 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, Lake Charles Mun, LA at 00:00Z on 2002-09-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1205 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, Lake Charles Mun, LA at 00:00Z on 2002-09-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 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
1205 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
955 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
5 m²/s²
0-3 km storm-relative helicity
-9 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WGUS54 KHGX 101101
FFWHOU
TXC167-101200-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
600 AM CDT TUE SEP 10 2002

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHERN GALVESTON COUNTY IN SOUTHEAST TEXAS

* UNTIL 700 AM CDT

* AT 555 AM CDT...DOPPLER RADAR INDICATED VERY HEAVY RAINFALL OVER   
  SOUTHWEST GALVESTON. NUMEROUS SHOWERS AND THUNDERSTORMS CONTINUE TO
  MOVE OVER THE SOUTH GALVESTON COUNTY...WITH THE HEAVIEST ACTIVITY
  OVER WEST GALVESTON ISLAND AND THOSE AREAS SOUTHWEST OF HITCHCOCK. 
  
* FLOODING IS EXPECTED IN OR NEAR...
  GALVESTON STATE PARK...JAMAICA BEACH...PIRATES BEACH               
  ...INDIAN  BEACH...WEST BEACH

DO NOT CROSS ANY LOCATION WHERE WATER COVERS THE ROAD

PLEASE REPORT FLOODING TO THE COUNTY SHERIFF...LOCAL POLICE...OR
DEPARTMENT OF PUBLIC SAFETY. THEY WILL RELAY YOUR REPORT TO THE
NATIONAL WEATHER SERVICE.

LAT...LON 2931 9485 2932 9480 2917 9504 2940 9519

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Sep 10, 3:19 AM CDT, 2 hours 42 minutes earlier.

Area forecast discussion, Sep 10, 3:19 AM CDT, 2 hours 42 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
300 AM CDT TU SEP 10 2002

EAST TO WEST TRAINING OF SHRA/TSRA BETWEEN SAN LUIS PASS AND SARGENT
TO BETWEEN WEST COLUMBIA AND SWEENEY CONTINUES. BRAZORIA COUNTY
GETTING SOAKED AGAIN AND LAST 4 DAYS KHGX WSR-88D INDICATED THE AREA
BETWEEN SAN LUIS PASS AND FREEPORT MAY HAVE RECEIVED OVER 20 INCHES.
DITTO FOR A SMALL AREA NEAR SWEENEY. IR LOOP INDICATE CLOUD TOP
COOLING FROM CONVECTION EARLY THIS MORNING OVER BRAZORIA AND
MATAGORDA COUNTIES. SURFACE ANALYSIS INDICATE CONFLUENT FLOW OVER
REGION W/WEAK COASTAL TROUGHING FROM THE SOUTH. PWATS STILL HIGH
OVER SOUTHWEST HALF OF REGION ABOUT 2.1 TO 2.4 INCHES. MODELS AGREE
IN SHIFTING MOISTURE RIDGE GRADUALLY SOUTH TODAY. WILL CONTINUE
FLASH FLOOD WATCH FOR BRAZORIA...WHARTON...MATAGORDA AND JACKSON
COUNTIES. HOWEVER...DO NOT EXPECT THIS SCENARIO TO CONTINUE INTO THE
AFTERNOON HOURS WITH HIGH PRESSURE RIDGE TO THE NORTH ADVECTING
RELATIVELY DRIER AIR ACROSS SOUTHEAST TEXAS. WE WILL CONTINUE W/THE
COASTAL FLOOD WATCH TODAY. MODERATE TO STRONG LOW LEVEL EASTERLY
FLOW SHOULD PREVAIL ALONG THE COAST. KHGX VAD WIND PROFILE INDICATE
30 KT EAST-NORTHEAST WINDS AT 1 KFT. CAUTION CONDITIONS REMAIN FOR
COASTAL WATERS W/SEAS AND WINDS JUST BELOW SCA THRESHOLD.

AVN AND ETA DIFFER RADICALLY IN HANDLING DEVELOPMENT OF SURFACE LOW
OVER THE GULF FOR WEDNESDAY AND THURSDAY. AVN SHOWS CLOSED LOW OVER
EASTERN GULF WHILE ETA SHOWS CLOSED LOW JUST OFF MEXICAN COAST SOUTH
OF BROWNSVILLE. FOR OUR REGION...WE STILL WOULD BE UNDER THE
INFLUENCE OF HIGH PRESSURE RIDGING W/NE FLOW W/TAIL END OF WEAK
FRONTAL BOUNDARY NEARBY.

UPPER TROUGH APPROACHING FROM THE NORTHWEST TOWARDS END OF THE
WEEKDAY W/CONSEQUENT LOWERING OF PRESSURES LEE OF ROCKIES AND RETURN
OF ONSHORE FLOW FOR US. HIGH PRESSURE FOLLOWING THIS TROUGH WILL
RESULT IN A COLD FRONT PERHAPS LATE IN THE COMING WEEKEND. MRF
INTERESTINGLY ENOUGH INDICATING BROAD AREA OF LOWER PRESSURE FROM SW
GULF TO WESTERN CARRIBEAN NEXT WEEK.

37/42

.HGX...FLASH FLOOD WATCH BRAZORIA/MATAGORDA/WHARTON/JACKSON COUNTIES.
       SCEC GULF WATERS 0-60NM.
       COASTAL FLOOD WATCH ENTIRE COAST INCLUDING BAYS.

PRELIMS...
CLL BB 092/072 094/071 093 31-
IAH EB 090/072 092/072 092 41-
GLS TE 087/078 090/078 089 52-

In the hours before

Special weather statement, Sep 10, 1:13 AM CDT, 4 hours 48 minutes before
TXZ227-237-100815-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
113 AM CDT TUE SEP 10 2002

...LINE OF SHOWERS AND THUNDERSTORMS WITH GUSTY WINDS MOVING ACROSS
BRAZORIA COUNTY AND HEADED TOWARD FORT BEND COUNTY...

AT 100 AM CDT...RADAR INDICATED A LINE OF SHOWERS AND THUNDERSTORMS
MOVING WEST NORTHWEST ACROSS BRAZORIA COUNTY. STRONG GUSTY WINDS
BETWEEN 40 AND 50 MPH ARE LIKELY WITH THESE STORMS...ESPECIALLY ACROSS
THE NORTHERN AND WESTERN PORTIONS OF THE COUNTY FROM ROSHARON TO
DAMON.

AS THIS LINE OF STORMS MOVES INTO FORT BEND COUNTY...STRONG WIND
GUSTS BETWEEN 40 AND 50 MPH ARE POSSIBLE. PERSONS ALONG AND SOUTH OF
HIGHWAY 59 SHOULD BE ALERT FOR THESE STORMS AS THEY APPROACH THE
AREA BETWEEN 125 AM AND 200 AM.

DUE TO VERY SATURATED GROUNDS...THESE GUSTY WINDS HAVE THE POTENTIAL
TO CAUSE DAMAGE...INCLUDING THE DOWNING OF TREES.

STAY TUNED TO NOAA WEATHER RADIO OR OTHER WEATHER NEWS SOURCES FOR
FURTHER UPDATES ON THIS WEATHER EVENT.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 10, 1:58 AM CDTFlash Flood WarningHGXBrazoria, Matagorda3 hr
Sep 10, 4:18 AM CDTFlash Flood WarningHGXGalveston102 min
Sep 10, 5:00 AM CDTFlash Flood WarningHGXBrazoria, Matagorda2 hr
Sep 10, 7:01 AM CDTFlash Flood WarningHGXBrazoria, Galveston119 min

Nearby

Flash Flood Warnings in Texas, 2002Every flash flood 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.