Alert archive / Texas / Flash Flood Warnings in 1997
Flash Flood Warning 91, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this flash flood warning at Dec 20, 1997, 10:15 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
- Dec 20, 1997, 10:15 PM CST (04:15 UTC)
- Expired
- Dec 21, 1997, 1:15 AM 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 04:15 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, 4.3 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.
- 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
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KHOU 210416 FFWHOU TXC201-210715- BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 1015 PM CST SAT DEC 20 1997 THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A FLASH FLOOD WARNING EFFECTIVE UNTIL 115 AM CST FOR PEOPLE IN THE FOLLOWING LOCATION... IN SOUTHEAST TEXAS ...HARRIS COUNTY AT 1015 PM...RADAR INDICATED NUMEROUS SHOWERS AND THUNDERSTORMS...SOME CONTAINING VERY HEAVY RAIN...EXTENDING EAST OF A LINE FROM TOMBALL TO SUGARLAND. A GROWING CLUSTER OF STORMS ALONG HIGHWAY 288 FROM THE SOUTH LOOP DOWN TO WEST COLUMBIA IN BRAZORIA COUNTY WILL MOVE INTO THE EAST SIDE OF HOUSTON FROM A LAKE HOUSTON TO HUMBLE TO CHANNELVIEW TO SOUTHEAST HOUSTON AREA THROUGH 1 AM. ALL STORMS ARE MOVING TO THE NORTHEAST AT 45 MPH. RAINFALL RATES WILL AVERAGE BETWEEN 1 AND 1.25 INCHES PER HOUR...AND THESE RAINS WILL LIKELY LEAD TO FLOODING AT LOCATIONS ALREADY WET FROM EARLIER RAINS. SOME SPOTS IN NORTHERN AND WESTERN HARRIS COUNTY HAVE ALREADY RECEIVED BETWEEN 2 AND 4 INCHES OF RAIN FROM EARLIER STORMS. THIS CONTINUES TO BE A DANGEROUS FLOOD AND FLASH FLOOD THREAT. MOST DEATHS IN FLASH FLOODING OCCUR IN AUTOMOBILES. DO NOT ATTElMPT 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 Dec 20, 8:10 PM CST, 2 hours 5 minutes earlier.
Area forecast discussion, Dec 20, 8:10 PM CST, 2 hours 5 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...
In the hours before
Special weather statement, Dec 20, 4:15 PM CST, 6 hours before
GMZ330-335-350-355-370-375-TXZ-176>179-195>200-210>214-226- 227-235>238-210400- SEVERE WEATHER OUTLOOK NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 415 PM CST SAT DEC 20 1997 ...SEVERE WEATHER POSSIBLE ACROSS SOUTHEAST TEXAS TONIGHT... THERE IS A SLIGHT RISK FOR SEVERE WEATHER ACROSS ALL OF SOUTHEAST TEXAS TONIGHT. A LINE OF STRONG THUNDERSTORMS WAS DEVELOPING OVER THE HILL COUNTRY THIS AFTERNOON. THIS LINE WILL BE MOVING SLOWLY INTO SOUTHEAST TEXAS THIS EVENING. THE AIRMASS OVER THE REGION REMAINS UNSTABLE AND VERY MOIST. AIDED BY POWERFUL JETSTREAM DYNAMICS...FAVORABLE WIND SHEAR WITH HEIGHT AND DISTURBANCES ROTATING AROUND AN IMPRESSIVE UPPER LEVEL STORM SYSTEM...SOME OF THE THUNDERSTORMS THAT DO DEVELOP MAY BECOME SEVERE. THE MAIN THREAT OF SEVERE WEATHER WILL FROM DAMAGING DOWNBURST WINDS ALTHOUGH A FEW ISOLATED TORNADOES ARE ALSO POSSIBLE. MARINE INTERESTS SHOULD ANTICIPATE STRONG THUNDERSTORMS DEVELOPING AND MOVING NORTHWARD ACROSS THE UPPER TEXAS COASTAL WATERS THIS EVENING. THESE STORMS WILL BRING A THREAT OF WATERSPOUTS AND STRONG GUSTY WINDS. PERSONS IN THE WATCH AND OUTLOOK AREAS SHOULD REMAIN ALERT TO RAPIDLY CHANGING WEATHER CONDITIONS AND BE PREPARED TO MOVE TO A SAFE PLACE IF SEVERE WEATHER IS OBSERVED OR A WARNING IS ISSUED. SKYWARN SPOTTERS AND EMERGENCY MANAGEMENT OFFICIALS SHOULD BE ALERT FOR POSSIBLE ACTIVATION EARLY THIS EVENING AS THREATENING WEATHER BEGINS MOVING INTO THE AREA. MONITOR YOUR NOAA WEATHER RADIO...LOCAL RADIO OR TELEVISION...OR YOUR LOCAL CABLE PROVIDER...FOR FURTHER UPDATES OR WARNINGS ON THIS DEVELOPING WEATHER SITUATION.
The office that day
Everything else NWS Houston/Galveston, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 20, 6:43 PM CST | Severe Thunderstorm Warning | HGX | Harris | 62 min |
| Dec 20, 7:07 PM CST | Flash Flood Warning | HGX | Harris | 3 hr |
| Dec 20, 8:22 PM CST | Tornado Warning | HGX | Liberty, Montgomery | 53 min |
| Dec 20, 8:41 PM CST | Flash Flood Warning | HGX | Liberty | 3 hr |
| Dec 20, 8:53 PM CST | Flash Flood Warning | HGX | Montgomery, San Jacinto | 3 hr |
| Dec 20, 11:32 PM CST | Flash Flood Warning | HGX | Liberty | 3 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.