Alert archive / Texas / Flash Flood Warnings in 1997

Flash Flood Warning 92, NWS Houston/Galveston, TX

December 20, 1997Liberty County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Dec 20, 1997, 11:32 PM CST for Liberty 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 counties it named.

The facts

Issued
Dec 20, 1997, 11:32 PM CST (05:32 UTC)
Expired
Dec 21, 1997, 2:30 AM CST
In force
3 hr
Issued by
NWS Houston/Galveston, TX
Area
Whole counties

County Liberty County, TX

The radar

The Houston radar (KHGX), 80 km from the middle of the area, began a volume at 05:35 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 00:00Z, 5.5 hours before the alert went out and 155 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 1997-12-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 1997-12-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 325 square meters per square second.1939587897117136Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
496 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
325 m²/s²
0-3 km storm-relative helicity
420 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 
TTAA00 KHOU 210532
FFWHOU
TXC291-210830-
 
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1132 PM CST SAT DEC 20 1997
 
THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  230 AM CST
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTHEAST TEXAS
 
   ...LIBERTY COUNTY
 
AT 1130 PM...RADAR CONTINUES TO SHOW NUMEROUS SHOWERS AND THUNDERSTORMS
EXTENDING FROM RYE TO DAYTON TO CHANNELVIEW TO MATAGORDA BAY. MOVEMENT
WAS NORTHEAST AT 45 MPH...RESULTING IN GOOD TRAINING ACROSS MOST OF
LIBERTY COUNTY. THIS TRAINING WILL LIKELY LEAD TO AN ADDITIONAL 1 TO 2
INCHES OF RAINFALL. THESE TOTALS COULD BRING EVENT AMOUNTS INTO A 7 TO
8 INCH RANGE...ESPECIALLY AROUND CLEVELAND AND AREAS SOUTHEAST OF THE
CITY.  A SERIOUS AND DANGEROUS FLOOD THREAT CONTINUES IN LIBERTY
COUNTY!
 
BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO
RECOGNIZE THE DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH
FLOODING IS OBSERVED...ACT QUICKLY. MOVE UP TO ESCAPE FLOOD
WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER
BEGINS RISING.

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 Dec 20, 8:10 PM CST, 3 hours 22 minutes earlier.

Area forecast discussion, Dec 20, 8:10 PM CST, 3 hours 22 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
810 PM CST SAT DEC 20 1997

THE RAINS HAVE ARRIVED AND WILL CONTINUE THROUGH 10Z FOR MOST OF THE
FA.  ATTM THE JET CRASHING THROUGH THE LINE OF CONVECTION SOUTH OF SAT
WILL BE ARRIVING IN FA SHORTLY.  THE MASS OF HEAVY RAIN THAT HAS BEEN
OVER THE NRN HILL COUNTY WILL PROPOGATE EAST IS THE SCENARIO EXPECTED
FOR THE NRN FA AS THE UPPER TROUGH AXIS COMES ENE...WITH THE TILT
BECOMING MORE FAVORABLE FOR THE OUTFLOW JET TO BE ENHANCED.  OVER THE
SOUTHERN HALF OF THE FA THE SURFACED BASED CONVECTION (IN MID 60S DWPTS)
WILL BE THE THREAT WITH SOME POSSIBLY SEVERE AND LOCALLY HEAVY RAIN
LIKELY. WILL CONTINUE THE FLASH FLOOD WATCH FOR FA AND CAN UP THE POPS
FOR CLL ZONES.  WILL ALSO LOWER MIN FOR CLL TONIGHT BASED ON UPSTREAM
TEMPS.
45

PRELIMS..
CLL  T/T>,E E/E  49/61 40/63  +2-0
IAH  T/T>,E E/E  55/63 42/65  +3-0 (1ST PD: SVR TSTMS & FFW)
GLS  T/T>,E E/E  59/64 52/64  +3-0 (1ST PD: SVR TSTMS & FFW AND WINDY)

ALL ZONES (PLEASE)...
(2ND PD: TSRA ENDING EARLY.  MC/RA)

GOTTA RUN...

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 20, 6:43 PM CSTSevere Thunderstorm WarningHGXHarris62 min
Dec 20, 7:07 PM CSTFlash Flood WarningHGXHarris3 hr
Dec 20, 8:22 PM CSTTornado WarningHGXLiberty, Montgomery53 min
Dec 20, 8:41 PM CSTFlash Flood WarningHGXLiberty3 hr
Dec 20, 8:53 PM CSTFlash Flood WarningHGXMontgomery, San Jacinto3 hr
Dec 20, 10:15 PM CSTFlash Flood WarningHGXHarris3 hr

Nearby

Flash Flood Warnings in Texas, 1997Every flash flood warning in 1997

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.