Alert archive / Texas / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 239, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this severe thunderstorm warning at Dec 20, 1997, 6:43 PM CST for Harris County, Texas. It was in force for 62 min. 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, 6:43 PM CST (00:43 UTC)
- Expired
- Dec 20, 1997, 7:45 PM CST
- In force
- 62 min
- 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 00:44 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, 0.7 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
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
What forecasters said that day
The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Dec 20, 2:40 PM CST, 4 hours 3 minutes earlier.
Area forecast discussion, Dec 20, 2:40 PM CST, 4 hours 3 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 240 PM CST SAT DEC 20 1997 EVOLUTION OF ADVERTISED WX EVENT A BIT SLOWER THAN EARLIER THINKING, BUT INGREDIENTS ARE COMING TOGETHER AS INDICATED BY CURRENT KHGX/EWX RADARS. N-S LINE OF SH/TSRA BEGINNING TO FORM BETWEEN SAT/AUS ALONG SOME SORT OF LOW-LVL CONVERGENCE LINE. CONVECTION NO DOUBT AIDED BY VERY IMPRESSIVE DIFFLUENCE ALOFT AS INDICATED BY SATELLITE WV LOOPS. VERTICAL WIND SHEAR PROFILES STILL SUPPORTIVE OF DAMAGING WIND GUSTS (AND POSSIBLY ISOLATED TORNADOES) WITH INFLOWS/THETA-E RIDGING STILL SUPPORTIVE OF SOME HEAVY RAIN. WOULD LIKE TO KEEP CURRENT HEADLINES INTACT FOR TONIGHT (SVR/FFA) TAPERING POPS A LITTLE FOR SUNDAY (UN- TIL THE COLD FRONT PUSHES THRU THE FA BY SUNDAY AFTN). HOWEVER, THE FRONT IS NOT EXPECTED TO STRAY TOO FAR E AS THE NEXT UPPER LEVEL LOW BEGINS TO DIG OVER SRN CA/CA BAJA. WINDS/AMS TO TURN AROUND QUICKLY (BY MON) WITH THE NEXT BEST SHOT OF PCPN/CONVECTION PROGGED FOR TUE. IN THE MEANWHILE, WILL CONTINUE WITH HIGH POPS AND NOT STRAY TOO FAR FROM GUIDANCE FOR TEMPS. 41 PRELIMS.. CLL T/>T,E E/E 52/61 40/63 72-0 IAH T/>T,E E/E 55/63 42/65 +3-0 GLS T/>T,E E/E 59/64 52/64 +3-0 ALL ZONES (PLEASE)... (1ST PD: SVR TSTMS & FFW) (2ND PD: TSRA ENDING. MC/RA)
In the hours before
Special weather statement, Dec 20, 4:14 PM CST, 2 hours 29 minutes 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.
Special weather statement, Dec 20, 4:15 PM CST, 2 hours 28 minutes 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, 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, 10:15 PM CST | Flash Flood Warning | HGX | Harris | 3 hr |
| Dec 20, 11:32 PM CST | Flash Flood Warning | HGX | Liberty | 3 hr |
Nearby
Severe Thunderstorm Warnings in Texas, 1997Every severe thunderstorm 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.