Alert archive / Texas / Severe Thunderstorm Warnings in 2001
Severe Thunderstorm Warning 18, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this severe thunderstorm warning at Mar 12, 2001, 4:21 AM CST for Montgomery County, Texas. It was in force for 39 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
- Mar 12, 2001, 4:21 AM CST (10:21 UTC)
- Expired
- Mar 12, 2001, 5:00 AM CST
- In force
- 39 min
- Issued by
- NWS Houston/Galveston, TX
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
County Montgomery County, TX
The radar
The Houston radar (KHGX), 101 km from the middle of the area, began a volume at 10:21 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Mar 12, 4:30 AM CST | Thunderstorm Wind | Montgomery, TX | Trees down at FM 149 and Spring Branch Road and at FM 149 and Karen Switch Road. |
| Mar 12, 5:05 AM CST | Thunderstorm Wind | Conroe, TX | Trees down on River Plantation Road near I-45. |
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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Mar 12, 2:00 AM CST | Severe Thunderstorm Watch | SPC | 4 hr |
The nearest sounding before it
Lake Charles Mun, LA (KLCH), launched 00:00Z, 10.4 hours before the alert went out and 222 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
- 75 J/kg
- Mixed-layer CIN
- -89 J/kg
- Mixed-layer LCL
- 790 m above ground
- 0-6 km bulk shear
- 65 kt
- 0-1 km storm-relative helicity
- 223 m²/s²
- 0-3 km storm-relative helicity
- 266 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
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 Mar 12, 2:10 AM CST, 2 hours 11 minutes earlier.
Area forecast discussion, Mar 12, 2:10 AM CST, 2 hours 11 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 210 AM CST MON MAR 12 2001 SQUALL LINE OVER CENTRAL TEXAS IS MOVING EAST AND WILL LIKELY AFFECT THE NORTHERN HALF OF SE TEXAS. IT APPEARS THAT THE 85H 14 DEGREE ISOTHERM DEFINES THE EDGE OF THE CAP. THIS ISOTHERM IS FORECAST TO DISSECT THE HGX CWA BY 12Z. LAPS DATA DOES SHOW CAPE INCREASING AND LI'S DROPPING. WL PROBABLY HAVE TO ISSUE SEVERAL SETS OF ZONES THIS MORNING FOR CONVECTION. LOOKS LIKE SOME CLEARING THIS AFTERNOON WITH NORTHWEST WINDS. WITH ADDITIONAL SUNSHINE...FEEL TEMPS WILL BE ON THE WARM SIDE. AVN/ETA TIME SECTIONS SHOW ABUNDANT MOISTURE AOA 50H SO EXPECT A CIRRUS SHIELD TUESDAY AND WEDNESDAY. EXTENDED: MODELS VERY AGGRESSIVE IN BRINGING MOISTURE BACK TO THE REGION LATE WEDNESDAY AND WEDNESDAY NIGHT. 50H LOW TRACKS ACROSS TX WED NIGHT BRINGING A GOOD CHANCE OF RAIN. RAIN SHUTS OFF EARLY THURSDAY. ANOTHER UPPER LOW DEVELOPS OVER THE SW U.S. BY SATURDAY WITH ANOTHER CHANCE OF RAIN BY SUNDAY. 43/41/48 .KHGX...SEVERE TSTM WATCH NORTHERN/WESTERN ZONES TIL 12Z. PRELIMS... CLL BB 077/049 074/052 067 200 IAH BB 078/053 075/055 068 300 GLS EB J074/057 072/060 068 300
In the hours before
Special weather statement, Mar 12, 2:11 AM CST, 2 hours 10 minutes before
TXZ163-164-176>179-195>199-210>212-121200- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 211 AM CST MON MAR 12 2001 ...SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR AREAS ALONG AND NORTH OF A COLUMBUS TO HEMPSTEAD TO CONROE TO LIVINGSTON TILL 6 AM.... THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR THE FOLLOWING COUNTIES...COLORADO...AUSTIN...WALLER... MONTGOMERY...SAN JACINTO...POLK...WASHINGTON...GRIMES...WALKER... TRINITY...BURLESON...BRAZOS...MADISONVILLE...AND HOUSTON COUNTIES. THE MAJOR CITIES OF BRYAN/COLLEGE STATION...CROCKETT... GROVETON...LIVINGSTON...CONROE...COLUMBUS...BELLVILLE...AND HUNTSVILLE ARE INCLUDED IN THE WATCH AREA. A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL MOVE INTO THE WATCH AREA BRINGING THE THREAT STRONG DAMAGING WINDS...HAIL AND POSSIBLY ISOLATED TORNADOES. THIS LINE SHOULD REACH THE WESTERN AREAS IN THE WATCH AROUND 3 AM FOLLOWED BY A TRINITY TO CONROE TO COLUMBUS LINE AROUND 5 AM. BRIEF HEAVY RAINFALL WILL ALSO ACCOMPANY THESE STORMS WITH ACCUMULATIONS OF 1 TO 2 INCHES POSSIBLE. REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE FOR THE DEVELOPMENT OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WIND IN EXCESS OF 55 MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING AND VERY HEAVY RAIN IN AND NEAR THE WATCH AREA. IF SEVERE WEATHER THREATENS...MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. IF OUTSIDE...MOVE TO SHELTER... PREFERABLY INSIDE A STRONG BUILDING. EMERGENCY MANAGERS AND STORM SPOTTERS SHOULD PREPARE FOR ACTIVATION. STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO OR TELEVISION STATIONS...OR YOUR CABLE TELEVISION SERVICE PROVIDER THROUGH OUT THE NIGHT FOR THE LATEST STATEMENTS AND WARNINGS.
The office that day
Everything else NWS Houston/Galveston, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 12, 2:32 AM CST | Severe Thunderstorm Warning | HGX | Burleson, Washington | 58 min |
| Mar 12, 3:08 AM CST | Severe Thunderstorm Warning | HGX | Brazos, Grimes, Madison | 67 min |
| Mar 12, 3:39 AM CST | Severe Thunderstorm Warning | HGX | Washington | 36 min |
| Mar 12, 4:42 AM CST | Severe Thunderstorm Warning | HGX | San Jacinto, Walker | 78 min |
| Mar 12, 4:58 AM CST | Severe Thunderstorm Warning | HGX | Montgomery | 32 min |
Nearby
Severe Thunderstorm Warnings in Texas, 2001Every severe thunderstorm warning in 2001
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.