Alert archive / Texas / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 39, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this severe thunderstorm warning at Apr 11, 1997, 5:45 AM CDT for Brazoria County, Texas. It was in force for 60 min. 2 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Apr 11, 1997, 5:45 AM CDT (10:45 UTC)
- Expired
- Apr 11, 1997, 6:45 AM CDT
- In force
- 60 min
- Issued by
- NWS Houston/Galveston, TX
- Area
- Whole counties
County Brazoria County, TX
The radar
The Houston radar (KHGX), 48 km from the middle of the area, began a volume at 10:45 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Apr 11, 6:25 AM CDT | Thunderstorm Wind | Lake Jackson, TX | |
| Apr 11, 6:26 AM CDT | Thunderstorm Wind | Brazoria, TX |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Lake Charles Mun, LA (KLCH), launched 00:00Z, 10.8 hours before the alert went out and 240 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
- 22 J/kg
- Mixed-layer CIN
- -81 J/kg
- Mixed-layer LCL
- 946 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 11 m²/s²
- 0-3 km storm-relative helicity
- 108 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 111044 RRA SVRHOU TXC039-111145- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 545 AM CDT FRI APR 11 1997 THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 645 AM CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN SOUTHEAST TEXAS ...SOUTHERN BRAZORIA COUNTY AND ADJACENT COASTAL WATERS AT 544 AM...A LINE OF SEVERE THUNDERSTORMS STRETCHED FROM 3 MILES SOUTHEAST OF ANGLETON TO NEAR SARGENT. THESE STORMS WILL MOVE TO THE EAST-SOUTHEAST AT 20 MPH. THIS SEVERE THUNDERSTORM WILL LIKELY PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH...DESTRUCTIVE HAIL...AND VERY HEAVY RAIN.J MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. STAY AWAY FROM WINDOWS.
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 Apr 11, 2:46 AM CDT, 2 hours 59 minutes earlier.
Area forecast discussion, Apr 11, 2:46 AM CDT, 2 hours 59 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION ...MORE ON SECOND PAGE NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 245 AM CDT FRI APR 11 1997 ...VERY DANGEROUS FLOODING SITUTATION UNDERWAY... MCS THAT MOVED INTO THE SW ZONES SHOULD SLOW IN ITS NORTHEASTWARD MOVEMENT AND BEGIN TO TURN MORE EAST AFTER 3 AM. LOW LEVEL/MESOSCALE FEATURES INDICATING THAT SIGNIFICANT TRAINING WILL BE A PROBLEM THROUGH 12Z. AND TO TOP IT ALL OFF IT APPEARS FROM WATER VAPOR THAT OUTFLOW JET BECOMING PRONOUNCED ON THE WEST SIDE OF THE COMPLEX HELPING IN THE ORGANIZATION. RADAR ALREADY INDICATING STORM TOTAL RAINFALL ACCUMULATIONS OF AROUND 5 INCHES NEAR EL CAMPO AND 9 TO 10 INCHES NEAR HALLETSVILLE! (SOME OF THE PRECIP OVER THESE AREAS MAY BE GETTING SOME HAIL CONTAMINATION...ALTHOUGH SO FAR NO GROUNDTRUTH BACK OF HAIL WITH THESE STORMS.) ALSO OF NOTE THE VERY STRONG MESO ALONG THE SLOW MOVING PSEUDO WARM FRONT OVER WATER. AT THIS RATE NOT ONLY WILL WE HAVE FLOODING PROBLEMS BUT SEVERE AS WELL. WILL NEED TO EXPAND FFA A LITTLE FURTHER NORTH AND MUCH FURTHER EAST AND ADD MENTION OF SEVERE FOR A LARGE PART OF THE AREA...ALTHOUGH THE SPEED SHEAR IS NOT TREMENDOUS THE TURNING IS IMPRESSIVE AND THE CAPE IS RATHER APPARENT BY LOOKING AT THE REFLECTIVITY MAXIMA ALOFT A NUMBER OF STORMS DEVELOPING STRONG MESOS OVER THE SW ZONES. LATEST 3HR PRECIP ESTIMATES RUNNING IN EXCESS OF 7 INCHES. ........................................................... 245 AM COMPLEX MOVING SLOWLY NORTH WITH DEVELOPMENT ALONG THE EASTERN FLANK. WILL RUN FFA SOUTH OF A BRENHAM TO CONROE TO LIBERTY LINE. ON DOWN THE ROAD AFTER THIS FIRST COMPLEX SHIFTS EAST THIS MORNING IT LOOKS AS THOUGH UPPER SUPPORT REMAINS FAVORABLE FOR ANOTHER ROUND OF THUNDERSTORMS THIS AFTERNOON SOME SEVERE AND LOCALLY HEAVY RAIN POSSIBLE. THE FRONT WILL BE SWEEPING THE AREA OUT AND PRODUCING GUSTS NEAR GALE OVER THE NEARSHORE WATERS AROUND 01Z. MAY BECOME PARTLY CLUODY BY SATURDAY AFTERNOON. CURSORY LOOK AT NUMBERS FOLLOWS CLL 78/47/62/46 5200 IAH 79/51/64/46 7300 GLS 77/59/66/56 8500
The office that day
Everything else NWS Houston/Galveston, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 10, 10:26 PM CDT | Severe Thunderstorm Warning | HGX | Matagorda | 59 min |
| Apr 10, 11:40 PM CDT | Severe Thunderstorm Warning | HGX | Wharton | 65 min |
| Apr 11, 12:45 AM CDT | Severe Thunderstorm Warning | HGX | Wharton | 60 min |
| Apr 11, 1:07 AM CDT | Flash Flood Warning | HGX | Wharton | 118 min |
| Apr 11, 1:40 AM CDT | Tornado Warning | HGX | Wharton | 65 min |
| Apr 11, 2:04 AM CDT | Tornado Warning | HGX | Fort Bend | 61 min |
| Apr 11, 2:28 AM CDT | Flash Flood Warning | HGX | Fort Bend, Wharton | 3 hr |
| Apr 11, 2:28 AM CDT | Tornado Warning | HGX | Brazoria | 62 min |
| Apr 11, 2:40 AM CDT | Severe Thunderstorm Warning | HGX | Wharton | 65 min |
| Apr 11, 2:58 AM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Fort Bend | 62 min |
| Apr 11, 3:42 AM CDT | Severe Thunderstorm Warning | HGX | Matagorda, Wharton | 33 min |
| Apr 11, 3:59 AM CDT | Severe Thunderstorm Warning | HGX | Brazoria | 61 min |
| Apr 11, 4:08 AM CDT | Flash Flood Warning | HGX | Brazoria | 3 hr |
| Apr 11, 4:22 AM CDT | Tornado Warning | HGX | Brazoria, Galveston | 68 min |
| Apr 11, 5:23 AM CDT | Severe Thunderstorm Warning | HGX | Matagorda | 67 min |
| Apr 11, 5:26 AM CDT | Tornado Warning | HGX | Galveston | 64 min |
| Apr 11, 5:27 AM CDT | Severe Thunderstorm Warning | HGX | Harris | 63 min |
| Apr 11, 5:33 AM CDT | Flash Flood Warning | HGX | Galveston | 3 hr |
| Apr 11, 9:24 AM CDT | Flash Flood Warning | HGX | Wharton | 4 hr |
| Apr 11, 3:30 PM CDT | Severe Thunderstorm Warning | HGX | Harris | 60 min |
| Apr 11, 4:25 PM CDT | Severe Thunderstorm Warning | HGX | Harris, Montgomery | 65 min |
| Apr 11, 5:06 PM CDT | Severe Thunderstorm Warning | HGX | Liberty | 64 min |
| Apr 11, 5:17 PM CDT | Severe Thunderstorm Warning | HGX | Harris | 58 min |
| Apr 11, 6:11 PM CDT | Tornado Warning | HGX | Harris | 49 min |
| Apr 11, 6:45 PM CDT | Severe Thunderstorm Warning | HGX | Chambers | 60 min |
| Apr 11, 6:58 PM CDT | Severe Thunderstorm Warning | HGX | Harris | 32 min |
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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.