Flash Flood Warning 67, NWS Houston/Galveston, TX

Issued

Aug 31, 2001, 8:30 AM CDT (13:30 UTC)

Expired

Aug 31, 2001, 11:30 AM CDT

In force

3 hr

Issued by

NWS Houston/Galveston, TX

Area

Whole counties; the outline is the Mesonet’s reconstruction

Counties Colorado County, TX, Jackson County, TX, Matagorda County, TX, Wharton County, TX

The Houston radar (KHGX), 113 km from the middle of the area, began a volume at 13:32 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.

000 
WGUS54 KHGX 311334
FFWHOU
TXC089-239-321-481-311630-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
830 AM CDT FRI AUG 31 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  JACKSON COUNTY IN SOUTHEAST TEXAS
  COLORADO COUNTY IN SOUTHEAST TEXAS
  WHARTON COUNTY IN SOUTHEAST TEXAS
  MATAGORDA COUNTY IN SOUTHEAST TEXAS

* UNTIL 1130 AM CDT

* AT 825 AM CDT...DOPPLER RADAR INDICATED VERY HEAVY RAINFALL OVER 
MOST OF COLORADO...JACKSON...AND WHARTON COUNTY AND MOVING INTO 
WESTERN MATAGORDA COUNTY. RAINFALL RATES WERE ESTIMATED AT ONE TO 
TWO INCHES PER HOUR.  THE THUNDERSTORM PRODUCING THE HEAVY RAIN WERE 
MOVING NORTHEAST AT 20 MPH. 
 
* WIDESPREAD FLOODING OF ROADWAYS AND STREAMS IS EXPECTED TO 
CONTINUE OVER THE AREA THROUGH 1130 AM. NUMEROUS COUNTY ROADS AND 
SOME FARM TO MARKET ROADS WERE ALREADY FLOODED.  RAINFALL AMOUNTS 
OVERNIGHT AVERAGED AROUND 5 INCHES WITH 8 TO 12 INCHES OCCURRING IN 
AN AREA FROM MORALES AND GARWOOD EAST THROUGH BOLING. AN ADDITIONAL 
TWO TO THREE INCHES OF RAIN FROM THIS MORNINGS THUNDERSTORMS WILL 
QUICKLY POND OR RUNOFF INTO STREAMS AND ADD TO THE FLOODING. 

DO NOT DRIVE INTO FLOODED ROADWAYS OR INTO WATER OF UNKNOWN DEPTH. 
PAST RAIN EVENTS SIMILAR TO THIS HAVE RESULTED IN FLOODING OF 
HUNDREDS OF VEHICLES.

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 2958 9611 2875 9572 2880 9660 2958 9655

NWS Houston/Galveston, TX wrote its last area forecast discussion before this flash flood warning went out at Aug 31, 3:15 AM CDT, 5 hours 15 minutes earlier.

SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
315 AM CDT FRI AUG 31 2001

PROLONGED HEAVY RAIN EVENT CONTINUES. OVERNIGHT RAINFALL HAS BEEN
MUCH MORE WIDESPREAD THAN PREVIOUS NIGHTS THIS WEEK PLUS TOTALS HAVE
BEEN HIGHER THAN BEFORE.  RAINFALL SOUTH OF I-10 AND JUST INLAND
FROM THE COAST AVERAGING 3 TO 5 INCHES WITH SEVERAL POCKETS OF 7 TO
10 INCHES. GIVEN PWS IN EXCESS OF 2.25 THESE AMOUNTS NOT SURPRISING.
WEEKLY TOTALS IN SOME LOCATIONS WILL LIKELY EXCEED 15 INCHES...

SHORT TERM...CURRENT MCS SET UP EAST WEST WITH NORTHERN EDGE ALONG
I-10 AND SOUTHERN EDGE ROUGHLY SOUTHERN HOUSTON METRO AREA TO
VICTORIA. BANDS OF CONVECTION ORIENTED NORTH SOUTH FORMING OVER GULF
AND MOVING NORTH 25 OR SO THEN MERGING INTO MCS.  WITH DEEP
SOUTHERLY FLOW AT 25 TO 30 KTS FROM GULF EXPECT THIS TO CONTINUE
PAST SUNRISE BEFORE DIURNAL CHANGE...POSSIBLY TAKING CONVECTION
FURTHER SOUTH AND NEW CONVECTION FIRING INLAND NORTH OF I-10.
QPFERD UNDERSTATING POTENTIAL. EXPECT ANOTHER 3 TO 5 INCHES WITH
ISOLATED 5 TO 10 THROUGH NOON TODAY...UNFORTUNATELY IN SAME AREAS
WHERE HEAVY RAINFALL ALREADY OCCURRED. NEEDLESS TO SAY...FLASH FLOOD
WATCH TO CONTINUE. MODERATE LOW LEVEL JET ABOVE WEAK SURFACE FEATURE
PROVIDING JUST ENOUGH SHEAR FOR ISOLATED TORNADO THREAT.

MIDDAY THROUGH SATURDAY...HIGH MOISTURE...MID LEVEL TROUGH TO
WEST... ENTRANCE REGION OF JET WITH FAVORABLE UPPER DIVERGENCE AND
LOW LEVEL CONVERGENCE ZONE ALONG COASTAL COUNTIES REMAINS
ESSENTIALLY IN PLACE. THEREFORE POTENTIAL FOR MORE EXCESSIVE RAIN
AND FLOODING WILL CONTINUE.  MESOSCALE FEATURES WILL DICTATE WHERE
AND WHEN THE HEAVIEST RAIN WILL FALL.  MODELS SUGGEST ANOTHER
SIGNIFICANT IMPULSE WILL MOVE SLOWLY ACROSS THE AREA TONIGHT...
FORCING YET ANOTHER MAJOR MCS AND HEAVY RAIN ACROSS THE AREA.

EXTENDED...
SUNDAY INTO WEDNESDAY MRF KEEPS MID LEVEL TROUGH AND ABOVE NORMAL
MOISTURE OVER AREA. BEYOND THAT TROUGH DEEEPENING TO WEST AND RIDGE
BUILDING NORTHWARD OVER GULF COAST STATES SHOULD REDUCE RAIN CHANCE.
LOW CONFIDENCE IN MODEL SOLUTIONS AND WILL KEEP CHANCE IN THROUGH
PERIOD.

30/43/31/DH

.HGX...FFA ALL CWA TODAY.
       SCEC 20 TO 60 NM HIGH ISLAND TO THE MATAGORDA SHIP CHANNEL.

PRELIMS...
CLL...080/073 083/073 088 987
IAH...079/074 080/074 086 +87
GLS...083/079 083/079 086 +87

Flash Flood Warnings in Texas, 2001Every flash flood warning in 2001

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.