Alert archive / Texas / Flash Flood Warnings in 2001

Flash Flood Warning 77, NWS Houston/Galveston, TX

September 1, 2001Galveston County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Sep 1, 2001, 9:52 AM CDT for Galveston County, Texas. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Sep 1, 2001, 9:52 AM CDT (14:52 UTC)
Expired: Sep 1, 2001, 12:00 PM CDT
In force: 2 hr
Issued by: NWS Houston/Galveston, TX
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Galveston County, TX

The radar

The Houston radar (KHGX), 15 km from the middle of the area, began a volume at 14:54 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

Lake Charles Mun, LA (KLCH), launched 12:00Z, 2.9 hours before the alert went out and 182 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 265 J/kg
Mixed-layer CIN: -72 J/kg
Mixed-layer LCL: 801 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 53 m²/s²
0-3 km storm-relative helicity: 103 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

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

000 
WGUS54 KHGX 011450
FFWHOU
TXC167-011700-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
952 AM CDT SAT SEP 1 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

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

* UNTIL 1200 PM CDT

* AT 944 AM CDT...DOPPLER RADAR INDICATED VERY HEAVY RAINFALL 
  ACROSS GALVESTON COUNTY WITH RAINFALL RATES OF UP TO 2 TO 3
  INCHES PER HOUR. VERY HEAVY RAINFALL WILL CONTINUE ACROSS 
  GALVESTON COUNTY FOR THE NEXT TWO HOURS.

* FLOODING IS EXPECTED IN OR NEAR...
  BACLIFF...BAYOU VISTA...CLEAR LAKE SHORES...DICKINSON

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 2962 9486 2938 9468 2917 9500 2950 9520

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 1, 9:10 AM CDT, 42 minutes earlier.

Area forecast discussion, Sep 1, 9:10 AM CDT, 42 minutes before

SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
910 AM CDT SAT SEP 01 2001

LARGE CLUSTER OF TSRA ROLLING THROUGH THE HOUSTON AREA THIS MORNING
ASSOCIATED WITH DISTURBANCE ROTATING AROUND UPPER TROF. LITTLE HAS
CHANGED FROM THIS TIME YESTERDAY. 12Z ANALYSIS SHOWS 850-500 MB TROF
STILL OFF TO THE WEST OF CWA ACROSS CENTRAL TX WITH DEEPEST MOISTURE
(DEWPOINTS OF 16C AT 850 MB AND 8C AT 700 MB) POOLED OVER SE TX.
WEAK COASTAL BOUNDARY REMAINS IN PLACE TO SERVE AS FOCUS FOR
CONVECTION. NO REASON TO GET TOO CUTE WITH FCST. PER 06Z
MESOETA...SIGNIFICANT UVV CONTINUES ACROSS ALL BUT FAR NW ZONES
THROUGH THIS AFTERNOON. AXIS OF TROF MOVES OVER CWA TONIGHT
SIGNALING THE FIRST SIGN THAT ACTIVITY WILL FINALLY BE SHIFTING
EAST OF SE TX LATER IN THE WEEKEND. NO SIG CHANGES TO FCST.

35/38/48

.HGX...FFA ALL CWA TODAY.
       SCEC 0-60 NM HIGH ISLAND TO THE MATAGORDA SHIP CHANNEL.

CLL...TT 082/073 089/073 089 865
IAH...TT 080/075 087/075 088 +75
GLS...TT 083/079 086/079 087 +85

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 1, 6:40 AM CDT	Flash Flood Warning	HGX	Jackson, Matagorda, Wharton	3 hr
Sep 1, 8:36 AM CDT	Flash Flood Warning	HGX	Fort Bend	3 hr
Sep 1, 9:06 AM CDT	Flash Flood Warning	HGX	Harris	114 min

Nearby

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

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.