Alert archive / Texas / Flash Flood Warnings in 2002

Flash Flood Warning 52, NWS Houston/Galveston, TX

October 24, 2002Brazoria County, Galveston County, Harris County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Oct 24, 2002, 7:31 PM CDT for Brazoria County, Galveston County, Harris County, Texas. It was in force for 119 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
Oct 24, 2002, 7:31 PM CDT (00:31 UTC)
Expired
Oct 24, 2002, 9:30 PM CDT
In force
119 min
Issued by
NWS Houston/Galveston, TX
Area
Counties, with a storm outline in the text

Counties Brazoria County, TX, Galveston County, TX, Harris County, TX

The radar

The Houston radar (KHGX), 16 km from the middle of the area, began a volume at 00:32 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, 0.5 hours before the alert went out and 181 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 2002-10-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 252 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 2002-10-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 square meters per square second.193958Sfc1 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
252 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
525 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
161 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

000 
WGUS54 KHGX 250031 CCA
FFWHOU
TXC039-167-201-250230-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
730 PM CDT THU OCT 24 2002

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN HARRIS COUNTY IN SOUTHEAST TEXAS
  EASTERN BRAZORIA COUNTY IN SOUTHEAST TEXAS
  GALVESTON COUNTY IN SOUTHEAST TEXAS

* UNTIL 930 PM CDT

* AT 725 PM CDT...VERY HEAVY RAINFALL HAD MOVED EAST OF THE AREA.

* FLOODING IS EXPECTED TO CONTINUE IN OR NEAR...LEAGUE CITY...
  CLEAR LAKE...PEARLAND...JOHNSON SPACE CENTER...HOBBY AIRPORT...
  ELLINGTON FIELD...WEBSTER

ALTHOUGH HEAVY RAINFALL HAD MOVED EAST OF THESE LOCATIONS...RUNOFF 
WAS CONTINUING TO CAUSE FLOODING.  AT 715 PM FLOODING WAS REPORTED 
IN SOUTHEAST HARRIS COUNTY ON ALAMEDA ROAD...BEAMER ROAD...AND THE 
FEEDER ROADS OF INTERSTATE 45 IN SOUTHEAST HARRIS COUNTY AND 
NORTHERN GALVESTON COUNTY.  1 TO 2 FEET OF WATER WAS REPORTED ON THE 
FEEDER ROAD NEAR NASA ROAD 1 AND EL DORADO ROAD.

THE FLOOD WATERS ARE EXPECTED TO SLOWLY SUBSIDE THROUGH 915 PM.

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 2984 9493 2955 9501 2949 9492 2934 9491
          2936 9485 2935 9481 2939 9479 2954 9459
          2949 9456 2944 9466 2934 9476 2925 9485
          2898 9524 2945 9545 2965 9533

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 Oct 24, 3:00 PM CDT, 4 hours 31 minutes earlier.

Area forecast discussion, Oct 24, 3:00 PM CDT, 4 hours 31 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
300 PM CDT THU OCT 24 2002

CONVECTION NOW BECOMING WIDESPREAD OVER CWFA ESPECIALLY WESTERN
ZONES. STRONGER CELLS PROPAGATING JUST SOUTHWEST OF REGION WHERE
LIFTED INDECIES AND HELICITY VALUES ARE MUCH HIGHER. LOWER TO MID
70S DEWPOINTS ARE NOW EVIDENT ALONG COASTAL ZONES WHILE COOLER AIR
INLAND SHOWING 60S DEWPOINTS. GFS INDICATE OUR REGION WILL BE UNDER
INFLUENCE OF RIGHT ENTRANCE REGION OF UPPER JET NEXT FEW DAYS. LOW LEVEL
JET CORE WILL SHIFT TOWARDS OUR REGION TONIGHT W/PWATS GOING UP TO
AROUND 2 INCHES. UPPER LEVEL DIVERGENCE FIELD WILL LINGER ON THROUGH
SATURDAY. WE SHALL CONTINUE WITH THE FLASH FLOOD WATCH FOR ALL
COUNTIES...AND EXTEND IT THROUGH FRIDAY. FRONTAL BOUNDARY ALONG
COASTAL REGION WILL SHIFT TO THE NORTH OVERNIGHT AND PULL BACK
FRIDAY. DESPITE DIFFERING SOLUTIONS FROM MODELS...IT APPEARS THAT
THE SOUTHERN ZONES WILL BE IN A SURFACE TROUGHING ZONE FRIDAY
THROUGH SATURDAY W/NORTHERLY FLOW ELSEWHERE.  SLIGHT DRYING FROM
NORTH TO SOUTH ON SUNDAY WILL CONSEQUENT RESULT IN LOWER POPS.
HOWEVER UPPER FLOW STILL SOUTHWESTERLY SHOWING UPPER LOW OVER
ARIZONA. THIS LOW SHOULD OPEN UP AND MOVE ACROSS THE MID SECTION OF
CONUS BY MID PART OF NEXT WEEK. COLD CANADIAN AIR MASS APPEARS TO BE
HEADED OUR WAY. DRIER AND COLDER CONDITIONS SHOULD BE IN STORE
TOWARDS LATER PART OF NEXT WEEK.

WILL RAISE CAUTION FOR 0-60 NAUTICAL MILES COASTAL WATERS AS SEAS
AND WINDS SHOULD REACH THRESHOLD VALUES. EXPECT WINDS TO LOWER
SOMEWHAT AFTER MCS MOVE TO EAST OF REGION.

37/35/BT

.HGX...FFA ALL ZONES THROUGH FRIDAY.
       SCEC 0-60 NM COASTAL WATERS.

CLL TT 064/071 059/067 057 877
IAH TT 067/074 062/067 058 877
GLS TT 071/078 069/074 069 877
Hazardous weather outlook, Oct 24, 11:10 AM CDT, 8 hours 21 minutes before
GMZ300-330-335-350-355-370-375-TXZ163-164-176>179-195>200-210>214-226-
227-235>238-251200-

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1110 AM CDT THU OCT 24 2002

...FLOOD WATCH IN EFFECT TODAY AND TONIGHT...

.DAY ONE...
TODAY...AN UPPER LEVEL DISTURBANCE WILL PRODUCE STRONG THUNDERSTORMS
OVER THE SOUTHWEST PART OF SOUTHEAST TEXAS...AND SOME OF THE STORMS
MAY POSSIBLY BECOME SEVERE AS THE CONVECTION INTERACTS WITH A
FRONTAL BOUNDARY. SHOWERS AND THUNDERSTORMS WILL BECOME LIKELY
AREAWIDE BY AFTERNOON AS THIS DISTURBANCE COMBINES WITH A MOIST AND
UNSTABLE ATMOSPHERE. LOCALLY HEAVY RAIN WILL BE POSSIBLE THROUGH
TONIGHT ACROSS THE AREA. RAINFALL AMOUNTS TODAY ARE EXPECTED TO
AVERAGE A HALF TO 1 INCH WITH ISOLATED AMOUNTS OF 2 TO 4 INCHES
POSSIBLE. ADDITIONAL HEAVY RAINFALL IS POSSIBLE TONIGHT CONTINUING
THE FLOOD THREAT.

.SPOTTER CALL TO ACTION STATEMENT...SPOTTER ACTIVATION IS POSSIBLE
FOR JACKSON...MATAGORDA AND WHARTON COUNTIES TODAY.

.DAYS TWO THROUGH SEVEN...
FRIDAY THROUGH WEDNESDAY...THE MOIST SOUTHWEST FLOW ALOFT WITH A
SERIES OF EMBEDDED DISTURBANCES MOVING ACROSS THE REGION WILL
LIKELY BRING ROUNDS OF SHOWERS AND THUNDERSTORMS THROUGH THE WEEKEND
AND COPIOUS RAINFALL. THEREFORE A HEAVY RAINFALL AND FLOOD THREAT WILL
EXIST THROUGH SUNDAY. IN ADDITION...SEVERE THUNDERSTORMS ARE POSSIBLE
ON FRIDAY AS A LOW PRESSURE SYSTEM DEVELOPS IN SOUTH TEXAS AND MOVES
ACROSS SOUTHEAST TEXAS.

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 24, 7:29 PM CDTFlash Flood WarningHGXBrazoria, Galveston, Harris2 hr

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.