Alert archive / Texas / Tornado Watches in 2004

Tornado Watch 141

May 1, 200431 counties in Texas

The Storm Prediction Center issued this tornado watch at May 1, 2004, 3:50 AM CDT for 31 counties in Texas. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: May 1, 2004, 3:50 AM CDT (08:50 UTC)
Expired: May 1, 2004, 10:00 AM CDT
In force: 6 hr
Issued by: the Storm Prediction Center

All 31 counties

Angelina County, TX, Austin County, TX, Bastrop County, TX, Brazos County, TX, Burleson County, TX, Chambers County, TX, Colorado County, TX, Fayette County, TX, Fort Bend County, TX, Grimes County, TX, Hardin County, TX, Harris County, TX, Jasper County, TX, Jefferson County, TX, Lavaca County, TX, Lee County, TX, Liberty County, TX, Madison County, TX, Montgomery County, TX, Newton County, TX, Orange County, TX, Polk County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Trinity County, TX, Tyler County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 117 km from the middle of the area, began a volume at 08:51 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.

Warnings issued inside it

6 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
May 1, 4:38 AM CDT	Tornado Warning	HGX	Liberty	52 min
May 1, 5:17 AM CDT	Severe Thunderstorm Warning	HGX	Montgomery	43 min
May 1, 5:30 AM CDT	Tornado Warning	HGX	Liberty	45 min
May 1, 8:43 AM CDT	Flash Flood Warning	HGX	Harris, Montgomery, Polk, San Jacinto	107 min
May 1, 8:50 AM CDT	Tornado Warning	HGX	Harris	40 min
May 1, 9:08 AM CDT	Severe Thunderstorm Warning	LCH	Tyler	52 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 8.8 hours before the alert went out and 258 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: 493 J/kg
Mixed-layer CIN: -85 J/kg
Mixed-layer LCL: 688 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 155 m²/s²
0-3 km storm-relative helicity: 260 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 6.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS20 KWNS 010852
SEL1  
SPC WW 010850
TXZ000-CWZ000-011500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 141
NWS STORM PREDICTION CENTER NORMAN OK
350 AM CDT SAT MAY 1 2004

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       SOUTHEAST TEXAS
       COASTAL WATERS

EFFECTIVE THIS SATURDAY MORNING FROM 350 AM UNTIL 1000 AM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 65 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 45 MILES NORTH NORTHEAST OF PORT ARTHUR TEXAS
TO 80 MILES SOUTHWEST OF COLLEGE STATION TEXAS.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...CONTINUE...WW 138...WW 139...WW 140...

DISCUSSION...DISCRETE STORMS ARE EXPECTED TO DEVELOP ACROSS SERN TX
DURING THE NEXT SEVERAL HOURS...AHEAD OF PRIMARY CONVECTIVE LINE NOW
MOVING OUT OF CENTRAL TX. AIR MASS IS BECOMING INCREASINGLY UNSTABLE
AND CAP IS WEAKENING DUE TO INFLUX OF RICH GULF MOISTURE NOW
ADVECTING OFF THE GULF. WIND PROFILES ARE VERY FAVORABLE FOR
ROTATION WITH ANY DISCRETE DEVELOPMENT...AND THE THREAT OF TORNADOES
IS LIKEWISE INCREASING. TORNADO THREAT WILL BE GREATER AHEAD OF LINE
OF STORMS EXPECTED TO SHIFT SEWD TOWARDS THE UPPER TX COAST THIS
MORNING...THOUGH LARGE HAIL AND DAMAGING WINDS WILL ALSO BE A THREAT
BOTH WITH THE LINE OF STORMS AND WITH ANY PRE-FRONTAL DEVELOPMENT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 22020.


...EVANS

293,0934 284,0971 304,0971 312,0934

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 30, 7:00 PM CDT	Mesoscale Discussion	SPC	Bosque, Brown, Coleman, Comanche, Concho, Eastland and 11 more	90 min
Apr 30, 7:22 PM CDT	Mesoscale Discussion	SPC	Anderson, Bowie, Camp, Cass, Cherokee, Delta and 25 more	83 min
Apr 30, 7:40 PM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bowie, Camp, Delta, Ellis, Fannin and 20 more	5 hr
Apr 30, 8:14 PM CDT	Mesoscale Discussion	SPC	Archer, Clay, Collin, Cooke, Denton, Grayson and 8 more	91 min
Apr 30, 9:07 PM CDT	Mesoscale Discussion	SPC	Bosque, Brown, Comanche, Coryell, Erath, Hamilton and 8 more	53 min
Apr 30, 9:54 PM CDT	Mesoscale Discussion	SPC	Anderson, Bowie, Camp, Delta, Ellis, Franklin and 19 more	96 min
Apr 30, 10:34 PM CDT	Mesoscale Discussion	SPC	Brown, Coleman, Concho, Crockett, Edwards, Irion and 15 more	86 min
Apr 30, 11:35 PM CDT	Severe Thunderstorm Watch	SPC	Blanco, Concho, Crockett, Edwards, Gillespie, Irion and 13 more	5 hr
Apr 30, 11:56 PM CDT	Mesoscale Discussion	SPC	Chambers, Galveston, Grimes, Hardin, Harris, Jasper and 10 more	94 min
May 1, 12:50 AM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bell, Bosque, Bowie, Camp, Cass and 47 more	6 hr
May 1, 1:34 AM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bexar, Blanco, Comal, Concho and 24 more	86 min
May 1, 1:49 AM CDT	Mesoscale Discussion	SPC	Anderson, Bell, Cherokee, Falls, Freestone, Henderson and 5 more	86 min
May 1, 2:38 AM CDT	Mesoscale Discussion	SPC	Angelina, Sabine, San Augustine, Shelby	37 min
May 1, 3:10 AM CDT	Severe Thunderstorm Watch	SPC	Angelina, Sabine, San Augustine, Shelby	6 hr
May 1, 3:28 AM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bexar, Blanco, Concho, Crockett and 23 more	92 min
May 1, 3:41 AM CDT	Mesoscale Discussion	SPC	Austin, Brazoria, Brazos, Burleson, Chambers, Colorado and 18 more	64 min
May 1, 5:13 AM CDT	Mesoscale Discussion	SPC	Anderson, Cherokee, Harrison, Nacogdoches, Panola, Rusk and 1 more	92 min
May 1, 5:40 AM CDT	Severe Thunderstorm Watch	SPC	Atascosa, Bee, Bexar, Caldwell, DeWitt, Dimmit and 17 more	6 hr
May 1, 6:08 AM CDT	Mesoscale Discussion	SPC	Angelina, Austin, Brazos, Burleson, Chambers, Colorado and 24 more	97 min
May 1, 7:24 AM CDT	Mesoscale Discussion	SPC	Sabine, San Augustine, Shelby	96 min
May 1, 7:33 AM CDT	Mesoscale Discussion	SPC	Atascosa, Bee, Bexar, Caldwell, DeWitt, Dimmit and 16 more	87 min
May 1, 7:47 AM CDT	Mesoscale Discussion	SPC	Austin, Bastrop, Brazos, Burleson, Chambers, Colorado and 23 more	88 min
May 1, 9:16 AM CDT	Mesoscale Discussion	SPC	Brazoria, Chambers, Fort Bend, Galveston, Hardin, Harris and 3 more	59 min
May 1, 9:36 AM CDT	Mesoscale Discussion	SPC	Nueces	114 min
May 1, 9:45 AM CDT	Tornado Watch	SPC	Brazoria, Chambers, Fort Bend, Galveston, Hardin, Harris and 6 more	5 hr
May 1, 9:55 AM CDT	Severe Thunderstorm Watch	SPC	Brooks, Cameron, Hidalgo, Jim Hogg, Kenedy, Kleberg and 3 more	5 hr
May 1, 11:15 AM CDT	Mesoscale Discussion	SPC	Kenedy	2 hr
May 1, 1:14 PM CDT	Mesoscale Discussion	SPC	Willacy	2 hr

Nearby

Tornado Watches in Texas, 2004 Every tornado watch in 2004

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.