Alert archive / Texas / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 138, NWS Houston/Galveston, TX

October 11, 2001Harris County, Liberty County, Montgomery County, Texas

NWS Houston/Galveston, TX issued this severe thunderstorm warning at Oct 11, 2001, 10:00 AM CDT for Harris County, Liberty County, Montgomery County, Texas. It was in force for 45 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: Oct 11, 2001, 10:00 AM CDT (15:00 UTC)
Expired: Oct 11, 2001, 10:45 AM CDT
In force: 45 min
Issued by: NWS Houston/Galveston, TX
Area: Whole counties; the outline is the Mesonet’s reconstruction

Counties Harris County, TX, Liberty County, TX, Montgomery County, TX

The radar

The Houston radar (KHGX), 72 km from the middle of the area, began a volume at 15:02 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Oct 11, 8:00 AM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 3.0 hours before the alert went out and 196 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1805 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 496 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 95 m²/s²
0-3 km storm-relative helicity: 120 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 5.4

Open this sounding in Storm Lab

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 Oct 11, 9:05 AM CDT, 55 minutes earlier.

Area forecast discussion, Oct 11, 9:05 AM CDT, 55 minutes before

SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
905 AM CDT THU OCT 11 2001

MINI-SUPERCELLS CONTINUE ACROSS SERN TX. TV COVERAGE EARLIER CLEARLY
SHOWED A ROTATING WALL CLOUD AND FUNNEL WITH ONE STORM. RADAR
SIGNATURES WILL CONTINUE TO BE INCONCLUSIVE. HOWEVER...STORM MOTIONS
TOWARD THE NNE (010-030 DEGREES) AND TWO-GATE VELOCITY COUPLETS SEEM
TO BE THE BEST PREDICTORS. UPDATED THE ZONES FORECASTS TO ADD THE
TORNADO WATCH.

.HGX...NONE.

31/47/38/42/WT

PRELIMS...
CLL TE 083/066 088/060 078 833
IAH TE 084/068 087/065 080 833
GLS TE 083/075 083/072 081 843

In the hours before

Special weather statement, Oct 11, 4:40 AM CDT, 5 hours 20 minutes before

TXZ163-164-176>179-195>200-210>214-226-227-235>238-112200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
440 AM CDT THU OCT 11 2001

...ISOLATED AREAS OF HEAVY RAIN AND SEVERE WEATHER POSSIBLE TODAY...

...MORE SIGNIFICANT SEVERE WEATHER OUTBREAK POSSIBLE FRIDAY NIGHT...

A MOIST AIRMASS IS IN PLACE OVER SOUTHEAST TEXAS TODAY. A STRONG
UPPER LEVEL STORM SYSTEM AND A WEAKENING COLD FRONT MOVING SOUTH
INTO THE REGION WILL COMBINE TO PRODUCE AREAS OF RAIN AND
THUNDERSTORMS. SOME OF THE THUNDERSTORMS COULD PRODUCE RAINFALL
RATES OF AN INCH OR TWO PER HOUR...WITH TOTALS OF 4 OR 5 INCHES
POSSIBLE. BE ALERT FOR HIGH STANDING WATER IN AREAS OF HEAVY RAIN
TODAY. THERE IS ALSO A SLIGHT CHANCE THAT ONE OR TWO OF THE STORMS
COULD PRODUCE HAIL OR WIND GUSTS ABOVE 50 MPH.

A MORE SIGNIFICANT SEVERE WEATHER OUTBREAK MAY BE ON TAP FOR FRIDAY
NIGHT. A VERY STRONG UPPER LEVEL STORM SYSTEM AND ASSOCIATED COLD
FRONT WILL MOVE ACROSS THE REGION BY SATURDAY. SOUTH WINDS NEAR THE
SURFACE WILL BECOME STRONGER AND TURN MORE WESTERLY WITH INCREASING
ALTITUDE. THIS...COMBINED WITH STRONG INSTABILITY...WILL CAUSE SOME
OF THE THUNDERSTORMS TO ROTATE...POSSIBLY PRODUCING DAMAGING WIND
GUSTS AND EVEN ISOLATED TORNADOES. A LOWERING FREEZING LEVEL IN THE
ATMOSPHERE WILL ALSO LEAD TO A GREATER CHANCE OF THUNDERSTORMS
PRODUCING LARGE HAILSTONES. CONSIDER MAKING PREPARATIONS TODAY AND
FRIDAY FOR SEVERE WEATHER FRIDAY NIGHT. MAKE SURE TO HAVE BATTERY
OPERATED APPLIANCES AND FLASHLIGHTS READY IN CASE POWER IS
INTERRUPTED. AND REMEMBER...THE BEST PLACE TO BE IF YOU ARE IN THE
PATH OF A SEVERE THUNDERSTORM OR TORNADO IS INSIDE A REINFORCED
STRUCTURE AWAY FROM WINDOWS.

ADDITIONAL STATEMENTS WILL BE ISSUED LATER TODAY AND ON FRIDAY
CONCERNING THE POTENTIAL FOR SEVERE WEATHER.

END/46

Special weather statement, Oct 11, 7:51 AM CDT, 2 hours 9 minutes before

TXZ163-164-176>179-195>200-210>214-226-227-235>238-111800-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
751 AM CDT THU OCT 11 2001

...TORNADO WATCH IN EFFECT FOR SOUTHEAST TEXAS UNTIL 100 PM...

THE STORM PREDICTION CENTER HAS ISSUED A TORNADO WATCH FOR SOUTHEAST
TEXAS UNTIL 100 PM THIS AFTERNOON. SHOWERS AND THUNDERSTORMS
CONTINUE TO DEVELOP SOUTH OF A COLD FRONT THAT EXTENDS JUST SOUTH OF
A LINE FROM CHILDRESS TO HONDO. THE ATMOSPHERE IS DESTABILIZING SOUTH
OF THIS LINE...AND CAUSING THE THUNDERSTORMS TO INCREASE IN
INTENSITY.

THE FOLLOWING COUNTIES ARE INCLUDED IN THE WATCH...
HOUSTON...TRINITY...POLK...MADISON...WALKER...BRAZOS...SAN
JACINTO...GRIMES...BURLESON...MONTGOMERY...LIBERTY...
WASHINGTON...WALLER...HARRIS...AUSTIN...COLORADO...FORT
BEND...WHARTON...JACKSON...CHAMBERS...BRAZORIA...GALVESTON AND
MATAGORDA.

STAY TUNED TO NOAA WEATHER RADIO OR OTHER WEATHER NEWS SOURCES FOR
FURTHER UPDATES AND POSSIBLE WARNINGS.

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 11, 7:29 AM CDT	Tornado Warning	HGX	Harris	46 min
Oct 11, 8:15 AM CDT	Tornado Warning	HGX	Harris	60 min
Oct 11, 8:36 AM CDT	Tornado Warning	HGX	Montgomery, Walker	39 min
Oct 11, 9:15 AM CDT	Severe Thunderstorm Warning	HGX	Montgomery	45 min
Oct 11, 9:30 AM CDT	Severe Thunderstorm Warning	HGX	Harris	45 min
Oct 11, 10:45 AM CDT	Severe Thunderstorm Warning	HGX	Chambers, Liberty	45 min
Oct 11, 10:50 AM CDT	Tornado Warning	HGX	Brazoria	40 min
Oct 11, 12:11 PM CDT	Special Marine Warning	HGX		2 hr
Oct 11, 12:11 PM CDT	Special Marine Warning	HGX		2 hr
Oct 11, 6:11 PM CDT	Special Marine Warning	HGX		2 hr
Oct 11, 6:11 PM CDT	Special Marine Warning	HGX		2 hr

Nearby

Severe Thunderstorm Warnings in Texas, 2001 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.