Alert archive / Texas / Flash Flood Warnings in 1997

Flash Flood Warning 84, NWS Houston/Galveston, TX

November 28, 1997Harris County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Nov 28, 1997, 2:19 PM CST for Harris 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
Nov 28, 1997, 2:19 PM CST (20:19 UTC)
Expired
Nov 28, 1997, 5:15 PM CST
In force
3 hr
Issued by
NWS Houston/Galveston, TX
Area
Whole counties

County Harris County, TX

The radar

The Houston radar (KHGX), 52 km from the middle of the area, began a volume at 20:21 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, 8.3 hours before the alert went out and 213 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 1997-11-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 49 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 1997-11-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 245 square meters per square second.19395878Sfc1 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
49 J/kg
Mixed-layer CIN
-211 J/kg
Mixed-layer LCL
586 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
245 m²/s²
0-3 km storm-relative helicity
233 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 282022
FFWHOU
TXC201-282315-
 
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
219 PM CST FRI NOV 28 1997
 
THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  515 PM CST
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTHEAST TEXAS
 
   ...HARRIS COUNTY
 
AT 225 PM...DOPPLER WEATHER RADAR INDICATED A SLOW MOVING LINE OF
THUNDERSTORMS WHICH EXTENDED FROM THE WOODLANDS TO KATY. RAINFALL RATES
IN THIS LINE HAVE AVERAGED BETWEEN 1 TO 2 INCHES AND ANOTHER 1 TO 2
INCHES OF RAIN ARE EXPECTED THIS AFTERNOON. INDIVIDUAL STORMS CONTINUE
TO MOVE NORTH-NORTHEAST AT 40 MPH WHILE THIS LINE CONTINUES TO MOVE EAST
AT 10 TO 15 MPH.  RAIN WILL DEVELOP OVER THE REMAINING PORTION OF
HARRIS COUNTY LATER THIS AFTERNOON AND HEAVY RAIN WILL ACCUMULATE IN
THAT AREA LATE THIS AFTERNOON AND THIS EVENING.  FLOODING OF STREETS
IN THE WILLOWBROOK AREA HAVE BEEN REPORTED.
 
DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER
COVERS THE ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW
YOUR CAR TO CROSS SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD
BE ABANDONED QUICKLY. MOVE TO HIGHER GROUND.
 
MOST DEATHS IN FLAJSH FLOODING OCCUR IN AUTOMOBILES. DO
NOT ATTEMPT TO CROSS BRIDGES...DIPS...OR UNDERPASSES IF WATER
COVERS THE ROADWAY. NEVER TRY TO CROSS A FLOWING STREAM...EVEN A
SMALL ONE...ON FOOT.

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 Nov 28, 9:30 AM CST, 4 hours 49 minutes earlier.

Area forecast discussion, Nov 28, 9:30 AM CST, 4 hours 49 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
930 AM CST FRI NOV 28 1997

DEVELOPMENT OF CONVECTION AHEAD OF FRONT CONTINUES PRETTY MUCH AS HAS
BEEN ANTICIPATED OVER THE LAST COUPLE OF DAYS.  SINCE THE LINE IS SO
SOLID AND WE ARE GETTING CLUSTERS OF STORMS DEVELOPING AHEAD OF THE
MAIN LINE... WILL WANT TO BRING POPS UP TO 80 PERCENT THIS AFTERNOON
FOR ENTIRE FA.  SVR WX-WISE... HGX VWP IS SHOWING CONSIDERABLE E
COMPONENT IN LOWER 2K FT OF WINDS... SO MAY HAVE SOME LOW ROTATORS AS
CONVECTION SPINS UP AHEAD OF MAIN LINE (NOTE THAT DANGEROUS-LOOKING
CRP HODO IN SHARP HAS HELICITY APCHG 500).  ADDITIONALLY...  STILL
ANTICIPATING CAPES CLIMBING TO AROUND 2000 J/KG THIS AFTERNOON... SO
DESPITE WIMPY LOOKING STORMS IN CNTRL TX LINE AT THE MOMENT... EXPECT
THEY WILL BE GETTING A LITTLE FRISKIER AS SYSTEM PROGRESSES EWD INTO
THE SE TX SWAMPS

OTHER MINOR DIFFERENCES IN MODEL DATA FROM LAST NIGHTS RUN ARE A
MINOR SLOW DOWN OF THE UPPER LOW AND CONSEQUENTLY A CLOUDIER DAY SAT
THAN WAS PREVIOUSLY FORECAST.  CURRENT FORECAST HAS PICKED UP THESE
TRENDS...  SO ONLY BIG CHANGE REQUEST AT THIS TIME WILL BE TO POPS.

PRELIMS...
CLL E/E/B 75/52/67  851 (FOR 2ND PD...MNLY EVE SHRA/TSRA)

IAH E/E/B 76/56/69  861 (FOR 2ND PD...MNLY EVE SHRA/TSRA)

GLS E/E/E 75/62/71  861

38

In the hours before

Special weather statement, Nov 28, 10:28 AM CST, 3 hours 51 minutes before
TXZ176>179-195>200-210>214-226-227-235>238-511-513-281800-

SEVERE WEATHER AND HEAVY RAIN OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1030 AM CST FRI NOV 28 1997
...THERE WILL BE A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER SOUTHEAST
TEXAS TODAY AND TONIGHT...

A PACIFIC COOL FRONT ACCOMPANIED BY A STRONG UPPER LEVEL DISTURBANCE
WILL MOVE INTO VERY WARM...MOIST...AND UNSTABLE AIR OVER EAST AND
SOUTHEAST TEXAS TODAY PROVIDING A FAVORABLE ENVIRONMENT FOR SEVERE
THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER SOUTHEAST TEXAS AND
ADJACENT COASTAL WATERS.

ADDITIONALLY... THE SLOW EASTWARD SPEED OF THIS SYSTEM MAY RESULT IN
CLUSTERS OF THUNDERSTORMS OVERRUNNING A FEW AREAS REPEATEDLY...
PRODUCING ISOLATED LOCAL RAINFALL TOTALS OF 4 TO 6 INCHES.

THE PRIMARY THREAT OF SEVERE WEATHER WILL BE DAMAGING WINDS FROM A
CONCENTRATED LINE OF STRONG THUNDERSTORMS DEVELOPING AHEAD OF THE
COLD FRONT.  HOWEVER...ISOLATED TORNADOES WILL ALSO BE POSSIBLE...
ESPECIALLY IN ISOLATED STORMS WHICH MAY FORM IN ADVANCE OF THE MAIN
LINE OF THUNDERSTORMS.

AT 10 AM THIS MORNING... A LINE OF THUNDERSTORMS HAD DEVELOPED AHEAD
OF THE FRONT FROM NEAR AUSTIN TO NEAR DALLAS.  CLUSTERS OF STORMS HAD
ALSO BEGUN TO DEVELOP AHEAD OF THIS LINE FROM EDNA TO COLLEGE
STATION.  ALTHOUGH NONE OF THESE STORMS HAD DISPLAYED SEVERE
CHARACTERISTICS OF 10 AM... THE STORMS ARE EXPECTED TO INCREASE IN
INTENSITY AS THE SYSTEM MOVES EAST TODAY.

PERSONS IN SOUTHEAST TEXAS AND MARINERS ALONG THE UPPER TEXAS COAST
INCLUDING GALVESTON AND MATAGORDA BAYS SHOULD KEEP ABREAST OF THIS
DEVELOPING WEATHER SITUATION.

EMERGENCY MANAGERS AND STORM SPOTTERS IN SOUTHEAST TEXAS SHOULD BE
PREPARED FOR IMMEDIATE ACTIVATION.
Special weather statement, Nov 28, 10:30 AM CST, 3 hours 49 minutes before
TXZ176>179-195>200-210>214-226-227-235>238-511-513-281800-

SEVERE WEATHER AND HEAVY RAIN OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1030 AM CST FRI NOV 28 1997
...THERE WILL BE A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER SOUTHEAST
TEXAS TODAY AND TONIGHT...

A PACIFIC COOL FRONT ACCOMPANIED BY A STRONG UPPER LEVEL DISTURBANCE
WILL MOVE INTO VERY WARM...MOIST...AND UNSTABLE AIR OVER EAST AND
SOUTHEAST TEXAS TODAY PROVIDING A FAVORABLE ENVIRONMENT FOR SEVERE
THUNDERSTORMS THIS AFTERNOON AND TONIGHT OVER SOUTHEAST TEXAS AND
ADJACENT COASTAL WATERS.

ADDITIONALLY... THE SLOW EASTWARD SPEED OF THIS SYSTEM MAY RESULT IN
CLUSTERS OF THUNDERSTORMS OVERRUNNING A FEW AREAS REPEATEDLY...
PRODUCING ISOLATED LOCAL RAINFALL TOTALS OF 4 TO 6 INCHES.

THE PRIMARY THREAT OF SEVERE WEATHER WILL BE DAMAGING WINDS FROM A
CONCENTRATED LINE OF STRONG THUNDERSTORMS DEVELOPING AHEAD OF THE
COLD FRONT.  HOWEVER...ISOLATED TORNADOES WILL ALSO BE POSSIBLE...
ESPECIALLY IN ISOLATED STORMS WHICH MAY FORM IN ADVANCE OF THE MAIN
LINE OF THUNDERSTORMS.

AT 10 AM THIS MORNING... A LINE OF THUNDERSTORMS HAD DEVELOPED AHEAD
OF THE FRONT FROM NEAR AUSTIN TO NEAR DALLAS.  CLUSTERS OF STORMS HAD
ALSO BEGUN TO DEVELOP AHEAD OF THIS LINE FROM EDNA TO COLLEGE
STATION.  ALTHOUGH NONE OF THESE STORMS HAD DISPLAYED SEVERE
CHARACTERISTICS OF 10 AM... THE STORMS ARE EXPECTED TO INCREASE IN
INTENSITY AS THE SYSTEM MOVES EAST TODAY.

PERSONS IN SOUTHEAST TEXAS AND MARINERS ALONG THE UPPER TEXAS COAST
INCLUDING GALVESTON AND MATAGORDA BAYS SHOULD KEEP ABREAST OF THIS
DEVELOPING WEATHER SITUATION.

EMERGENCY MANAGERS AND STORM SPOTTERS IN SOUTHEAST TEXAS SHOULD BE
PREPARED FOR IMMEDIATE ACTIVATION.

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 28, 1:59 PM CSTFlash Flood WarningHGXMontgomery, San Jacinto3 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.