Alert archive / Texas / Flash Flood Warnings in 2001

Flash Flood Warning 78, NWS Houston/Galveston, TX

September 2, 2001Brazoria County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Sep 2, 2001, 2:00 PM CDT for Brazoria County, Texas. It was in force for 3 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 2, 2001, 2:00 PM CDT (19:00 UTC)
Expired: Sep 2, 2001, 5:00 PM CDT
In force: 3 hr
Issued by: NWS Houston/Galveston, TX
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Brazoria County, TX

The radar

The Houston radar (KHGX), 35 km from the middle of the area, began a volume at 19:03 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.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 7.0 hours before the alert went out and 230 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: 542 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 831 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 10 m²/s²
0-3 km storm-relative helicity: 37 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 021900
FFWHOU
FFWHOU
TXC039-022200-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
200 PM CDT SUN SEP 2 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

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

* UNTIL 500 PM CDT

* AT 155 PM CDT...LAW ENFORCEMENT REPORTED PORTIONS HIGHWAY 6
  BETWEEN MANVEL AND ALVIN AND FM 1462 NEAR HIGHWAY 36 IMPASSABLE.
  ALTHOUGH RAINFALL IS DIMINISHING SLIGHTLY ACROSS THE COUNTY...
  HEAVIER THUNDERSTORMS ARE DEVELOPING BETWEEN RICHMOND AND BAY
  CITY AND WILL MOVE ACROSS THE COUNTY IN THE NEXT COUPLE OF HOURS.
  ADDITIONAL RAINFALL AMOUNTS OF 2 TO 3 INCHES ARE POSSIBLE.

* FLOODING IS EXPECTED IN OR NEAR...
  ALVIN...ANGLETON...BRAZORIA...CLUTE...MANVEL...ROSHARON...
  WEST COLUMBIA...PEARLAND...SWEENY...LAKE JACKSON

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 2956 9526 2959 9540 2941 9549 2922 9584
          2887 9555 2909 9523 2927 9515

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 2, 9:30 AM CDT, 4 hours 30 minutes earlier.

Area forecast discussion, Sep 2, 9:30 AM CDT, 4 hours 30 minutes before

SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
930 AM CDT SUN SEP 2 2001

TSRA FIRING THIS MORNING MAINLY OVER BRAZORIA/GALVESTON/CHAMBERS
COUNTIES IN AREA OF DEEPEST MOISTURE AHEAD OF WEAK DISTURBANCE OVER
SOUTH CENTRAL TX. 12Z ANALYSIS SHOWS TROPICAL MOISTURE REMAINING IN
PLACE ACROSS EASTERN CWA...WITH 850 MB DEWPOINTS OF 16C...700 MB
DEWPOINTS OF 6C...AND DEWPOINTS IN THE UPPER 70S. WITH TSRA
CONCENTRATED AROUND EASTERN COASTAL ZONES WILL ADD MENTION OF HEAVY
RAINFALL THERE. BEST LIFT SHOULD REMAIN OVER THIS AREA THROUGH TODAY
PER LATEST MESOETA.  WV IMAGERY SHOWS LARGE AREA OF SUBSIDENCE
ACROSS CENTRAL TX WEST OF TROF AXIS WHICH IS ALSO PICKED UP BY
MESOETA. SUBSIDENCE WILL SPREAD ACROSS SE TX THIS AFTN AND ACT AS A
HINDRANCE TO CONVECTION. WILL LOWER POPS NRN HALF...AND RAISE THEM
FOR GLS. TEMPS ARE TRICKY...BUT NRN HALF SHOULD REACH THE LOWER 90S
TODAY WITH SUNSHINE. WILL LOWER TEMPS A LITTLE ELSEWHERE.

FOR OFFSHORE...ADDED CAUTION TO 20 TO 60 NM GROUPING.

35/38/48

.HGX...SCEC HI ISLAND TO MATAGORDA 20 TO 60 NM OUT.

PRELIMS...
CLL BT 092/074 088/074 086 325
IAH TT 088/074 088/074 086 525
GLS TT 085/077 087/079 087 725

In the hours before

Special weather statement, Sep 2, 12:20 PM CDT, 1 hour 40 minutes before

TXZ200-210>214-226-227-235>238-022300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1220 PM CDT SUN SEP 2 2001

...FUNNEL CLOUDS AND WATERSPOUTS POSSIBLE SOUTH OF I-10 TODAY...

NUMEROUS THUNDERSTORMS CONTINUE FROM BAY CITY TO HOUSTON TO ANAHUAC
SOUTH TO THE COAST. WITH THE TROPICAL AIRMASS IN PLACE...SHORT LIVED
FUNNEL CLOUDS OR WATERSPOUTS WILL BE POSSIBLE WITH SOME OF THESE
STORMS THIS AFTERNOON. WATERSPOUTS CAN POSE A SERIOUS THREAT TO
MARINERS.

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.