Alert archive / Texas / Tornado Watches in 2003

Tornado Watch 749

July 15, 200310 counties in Texas

The Storm Prediction Center issued this tornado watch at Jul 15, 2003, 6:40 AM CDT for 10 counties in Texas. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jul 15, 2003, 6:40 AM CDT (11:40 UTC)
Expired
Jul 15, 2003, 1:00 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center

Counties Brazoria County, TX, Chambers County, TX, Fort Bend County, TX, Galveston County, TX, Hardin County, TX, Harris County, TX, Jackson County, TX, Jefferson County, TX, Matagorda County, TX, Wharton County, TX

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 15, 6:41 AM CDTTornado WarningHGXChambers, Galveston49 min
Jul 15, 8:42 AM CDTFlash Flood WarningHGXChambers, Harris3 hr
Jul 15, 10:00 AM CDTFlash Flood WarningHGXBrazoria, Fort Bend, Galveston, Jackson, Matagorda, Wharton3 hr
Jul 15, 12:52 PM CDTFlash Flood WarningHGXBrazoria, Jackson, Matagorda, Wharton3 hr

Discussions around it

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

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 11.7 hours before the alert went out and 246 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-pSkew-T log-p diagram, Corpus Christi, TX at 00:00Z on 2003-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2292 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Corpus Christi, TX at 00:00Z on 2003-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 74 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
2292 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
1162 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.5

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 151142
SEL9  
SPC WW 151140
TXZ000-CWZ000-151800-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 749 
NWS STORM PREDICTION CENTER NORMAN OK 
640 AM CDT TUE JUL 15 2003

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

       UPPER TEXAS COAST
       COASTAL WATERS

EFFECTIVE THIS TUESDAY MORNING AND AFTERNOON FROM 640 AM UNTIL 100
PM CDT.

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

THE TORNADO WATCH AREA IS ALONG AND 30 STATUTE MILES EITHER SIDE
OF A LINE FROM 25 MILES WEST OF PALACIOS TEXAS TO 10 MILES NORTH
NORTHEAST OF PORT ARTHUR 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.




DISCUSSION...WEDGE OF MORE UNSTABLE AIR IN NE QUADRANT OF CLAUDETTE
APPEARS TO APPROACHING THE UPPER TX CST N OF GLS ATTM...PER REGIONAL
RADAR AND LIGHTNING DATA.  THIS AREA EXPECTED TO ADVANCE SLOWLY WWD
LATER THIS MORNING AS STORM CENTER CONTINUES W AT ABOUT 10 KTS. 
STRONG UNIDIRECTIONAL SHEAR ON HGX VWP SINCE 06Z SHOULD SHOW
INCREASING  LOW LEVEL DIRECTIONAL COMPONENT IN THE NEXT FEW HOURS...
ENHANCING POTENTIAL FOR LOW LEVEL STORM ROTATION/TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH EXTREME
TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI
WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 13545.


...CORFIDI

290,0965 302,0941 294,0934 282,0962 

WWUS20 KWNS 151142
SEL9  
SPC WW 151140
TXZ000-CWZ000-151800-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 749 
NWS STORM PREDICTION CENTER NORMAN OK 
640 AM CDT TUE JUL 15 2003

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

       UPPER TEXAS COAST
       COASTAL WATERS

EFFECTIVE THIS TUESDAY MORNING AND AFTERNOON FROM 640 AM UNTIL 100
PM CDT.

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

THE TORNADO WATCH AREA IS ALONG AND 30 STATUTE MILES EITHER SIDE
OF A LINE FROM 25 MILES WEST OF PALACIOS TEXAS TO 10 MILES NORTH
NORTHEAST OF PORT ARTHUR 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.




DISCUSSION...WEDGE OF MORE UNSTABLE AIR IN NE QUADRANT OF CLAUDETTE
APPEARS TO APPROACHING THE UPPER TX CST N OF GLS ATTM...PER REGIONAL
RADAR AND LIGHTNING DATA.  THIS AREA EXPECTED TO ADVANCE SLOWLY WWD
LATER THIS MORNING AS STORM CENTER CONTINUES W AT ABOUT 10 KTS. 
STRONG UNIDIRECTIONAL SHEAR ON HGX VWP SINCE 06Z SHOULD SHOW
INCREASING  LOW LEVEL DIRECTIONAL COMPONENT IN THE NEXT FEW HOURS...
ENHANCING POTENTIAL FOR LOW LEVEL STORM ROTATION/TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH EXTREME
TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI
WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 13545.


...CORFIDI

290,0965 302,0941 294,0934 282,0962

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 15, 1:41 AM CDTMesoscale DiscussionSPCAustin, Brazoria, Chambers, Colorado, Fort Bend, Galveston and 4 more3 hr
Jul 15, 7:57 AM CDTMesoscale DiscussionSPCBrazoria, Chambers, Fort Bend, Galveston, Hardin, Jackson and 3 more4 hr
Jul 15, 9:48 AM CDTMesoscale DiscussionSPCBrazoria, Calhoun, Colorado, DeWitt, Fort Bend, Goliad and 8 more117 min
Jul 15, 12:05 PM CDTTornado WatchSPCAransas, Brazoria, Calhoun, Chambers, Fort Bend, Galveston and 8 more7 hr
Jul 15, 3:00 PM CDTTornado WatchSPCAtascosa, Bee, DeWitt, Frio, Goliad, Jackson and 7 more7 hr

Nearby

Tornado Watches in Texas, 2003Every tornado watch in 2003

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.