Alert archive / Texas / Flash Flood Warnings in 2001

Flash Flood Warning 49, NWS Houston/Galveston, TX

June 9, 2001Montgomery County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Jun 9, 2001, 7:01 AM CDT for Montgomery 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
Jun 9, 2001, 7:01 AM CDT (12:01 UTC)
Expired
Jun 9, 2001, 10:00 AM CDT
In force
3 hr
Issued by
NWS Houston/Galveston, TX
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Montgomery County, TX

The radar

The Houston radar (KHGX), 97 km from the middle of the area, began a volume at 12:03 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, 0.0 hours before the alert went out and 218 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 12:00Z on 2001-06-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2262 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 12:00Z on 2001-06-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 50 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
2262 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
451 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
50 m²/s²
0-3 km storm-relative helicity
82 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 091206
FFWHOU
TXC339-091500-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
701 AM CDT SAT JUN 9 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

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

* UNTIL 1000 AM CDT

* AT 653 AM CDT...DOPPLER RADAR INDICATED MODERATE TO HEAVY RAINFALL 
OVER CENTRAL MONTGOMERY COUNTY FROM WOOD BRANCH... TO CONROE... TO 
NEAR MONTGOMERY.  RAINFALL ESTIMATES INDICATE UP TO 20 INCHES OF 
RAIN FELL OVERNIGHT BETWEEN CONROE AND WILLIS... AND THE CURRENT 
RAINS WILL CONTRIBUTE TO THE ONGOING FLOODING. 

* FLOODING IS EXPECTED IN OR NEAR...
  CONROE...CUT AND SHOOT...MAGNOLIA...PANORAMA VILLAGE

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 3033 9521 3010 9527 3017 9552 3020 9577
          3056 9581

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 Jun 9, 2:58 AM CDT, 4 hours 3 minutes earlier.

Area forecast discussion, Jun 9, 2:58 AM CDT, 4 hours 3 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
245 PM CDT FRI JUN 8 2001

...A DANGEROUS FLASH FLOOD THREAT CONTINUES FOR SOUTHEAST TEXAS...

TROPICAL DEPRESSION ALLISON REMNANTS A VERY EFFICIENT RAIN MACHINE!
4-6 INCHES/HOUR RADAR ESTIMATED RAINFALL RATES OVER HOUSTON METRO
AREA W/LARGE SWATH OF TRAINING VERY HEAVY RAINSHOWERS EXTENDING SW
TO BRAZORIA COUNTY. A BAD NIGHT INDEED. IF THIS KEEPS UP (ALREADY
THE 4TH NIGHT IN A ROW)...SOME AREAS MAY VERY WELL APPROACH THE
ANNUAL RAINFALL QUOTA.

HIGH PW VALUES >2 INCHES WILL CONTINUE THROUGH SUNDAY AT LEAST OVER
THE SOUTHERN REGIONS. MODELS SUGGEST SLOW SOUTHWARD MOVEMENT OF
TROPICAL LOW (REMNANTS OF ALLISON) AND SHOULD BE JUST S OF GLS BY 24
HOURS. CONFLUENT FLOW AT LOW AND MID LEVELS SUGGEST STRONGEST UVM
WILL BE SHIFTING SOUTHWARD TO COASTAL WATERS BY SUNDAY. BOTH AVN AND
ETA SHOWS CONTINUING DIVERGENCE ALOFT OVER REGION NEXT 24-36 HRS.
WILL CONTINUE FLASH FLOOD WATCH THROUGH TONIGHT FOR ALL OF CWFA.
AS UPPER LEVEL LOW SHIFTS TO NW GULF SUNDAY NIGHT...POPS SHOULD
DRAMATICALLY LOWER ESPECIALLY NORTHERN ZONES.

WILL STAY CLOSE TO MESO-ETA PROGGED SURFACE WINDS AND AREAL COVERAGE
OF PCPN. SURFACE FEATURES HAS BEEN INITIALIZED WELL OVER OUR REGION
BY THIS MODEL W/SURFACE LOW OVER SW ZONES AT 09/06Z.

MARINE AREA WILL HAVE CAUTION TODAY FOR COASTAL WATERS AS SURFACE
WINDS TO REMAIN IN THE 15 TO 20 KNOT RANGE. CONTINUED STRONG WINDS
DUE ACROSS GALVESTON BAYS WILL WARRANT A SMALL CRAFT ADVISORY.
NO FLAGS FOR MATAGORDA BAY. NO CHANGES TO EXTENDED FORECAST.

37/41

.HGX...FLASH FLOOD WATCH ALL OF SOUTHEAST TEXAS THROUGH TONIGHT.
       SCA GALVESTON BAY. SCEC COASTAL WATERS.

PRELIMS...
CLL TT 083/071 088/072 088 954
IAH TT 083/072 086/072 086 +96
GLS TT 084/075 084/075 084 ++7

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 8, 7:55 PM CDTFlash Flood WarningHGXHarris4 hr
Jun 8, 8:05 PM CDTFlash Flood WarningHGXBrazoria, Fort Bend3 hr
Jun 8, 9:22 PM CDTFlash Flood WarningHGXWashington3 hr
Jun 8, 10:00 PM CDTFlash Flood WarningHGXMontgomery4 hr
Jun 8, 11:00 PM CDTFlash Flood WarningHGXFort Bend2 hr
Jun 8, 11:57 PM CDTFlash Flood WarningHGXHarris3 hr
Jun 9, 12:47 AM CDTFlash Flood WarningHGXBrazoria, Fort Bend6 hr
Jun 9, 1:19 AM CDTFlash Flood WarningHGXGrimes, Waller, Washington6 hr
Jun 9, 1:30 AM CDTFlash Flood WarningHGXGalveston5 hr
Jun 9, 1:50 AM CDTFlash Flood WarningHGXMontgomery5 hr
Jun 9, 2:50 AM CDTFlash Flood WarningHGXHarris6 hr
Jun 9, 6:23 AM CDTFlash Flood WarningHGXGalveston2 hr
Jun 9, 6:36 AM CDTFlash Flood WarningHGXBrazoria, Fort Bend3 hr
Jun 9, 8:44 AM CDTFlash Flood WarningHGXGalveston2 hr
Jun 9, 8:50 AM CDTFlash Flood WarningHGXHarris, Montgomery6 hr
Jun 9, 12:34 PM CDTFlash Flood WarningHGXBrazoria, Fort Bend3 hr
Jun 9, 12:40 PM CDTFlash Flood WarningHGXLiberty3 hr
Jun 9, 1:08 PM CDTFlash Flood WarningHGXChambers, Galveston3 hr
Jun 9, 2:57 PM CDTFlash Flood WarningHGXHarris3 hr
Jun 9, 4:09 PM CDTFlash Flood WarningHGXChambers, Galveston111 min
Jun 9, 6:00 PM CDTFlash Flood WarningHGXChambers, Galveston, Harris3 hr

Nearby

Flash Flood Warnings in Texas, 2001Every 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.