Alert archive / Texas / Severe Thunderstorm Watches in 2003
Severe Thunderstorm Watch 856
The Storm Prediction Center issued this severe thunderstorm watch at Aug 11, 2003, 12:05 PM CDT for 14 counties in Texas. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 11, 2003, 12:05 PM CDT (17:05 UTC)
- Expired
- Aug 11, 2003, 6:00 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
Counties Austin County, TX, Brazoria County, TX, Colorado County, TX, Fort Bend County, TX, Galveston County, TX, Harris County, TX, Liberty County, TX, Matagorda County, TX, Montgomery County, TX, Polk County, TX, San Jacinto County, TX, Waller County, TX, Washington County, TX, Wharton County, TX
The radar
The Houston radar (KHGX), 84 km from the middle of the area, began a volume at 17:06 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
8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 12:41 PM CDT | Severe Thunderstorm Warning | HGX | Liberty, Montgomery | 64 min |
| Aug 11, 12:47 PM CDT | Severe Thunderstorm Warning | HGX | San Jacinto | 28 min |
| Aug 11, 1:39 PM CDT | Severe Thunderstorm Warning | HGX | Austin, Washington | 51 min |
| Aug 11, 1:54 PM CDT | Severe Thunderstorm Warning | HGX | Montgomery | 21 min |
| Aug 11, 2:13 PM CDT | Severe Thunderstorm Warning | HGX | Harris | 47 min |
| Aug 11, 2:36 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Galveston | 39 min |
| Aug 11, 3:29 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Matagorda, Wharton | 46 min |
| Aug 11, 4:39 PM CDT | Severe Thunderstorm Warning | HGX | Matagorda | 51 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 12:00Z, 5.1 hours before the alert went out and 253 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
- 1341 J/kg
- Mixed-layer CIN
- -35 J/kg
- Mixed-layer LCL
- 1100 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 6 m²/s²
- 0-3 km storm-relative helicity
- 63 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 111703
SEL6
SPC WW 111705
TXZ000-CWZ000-112300-
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 856
NWS STORM PREDICTION CENTER NORMAN OK
1205 PM CDT MON AUG 11 2003
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
SOUTHEAST TEXAS
COASTAL WATERS
EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 1205 PM UNTIL 600
PM CDT.
HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 60 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 50 MILES NORTHEAST OF HOUSTON TEXAS
TO 50 MILES NORTH NORTHWEST OF PALACIOS TEXAS.
REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES.
DISCUSSION...CLUSTER OF THUNDERSTORMS IS INCREASING NORTH OF
HOU...NEAR INTERSECTION OF OUTFLOW BOUNDARIES. THESE STORMS ARE
EXPECTED TO SPREAD SOUTHWARD TOWARD THE COAST THROUGH THE
AFTERNOON...POSSIBLY EXPANDING WESTWARD INTO VERY MOIST/UNSTABLE
AIRMASS. DAMAGING WINDS APPEAR TO BE THE MAIN THREAT.
AVIATION...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 36030.
...HART
291,0944 283,0963 301,0963 310,0944
WWUS20 KWNS 111703
SEL6
SPC WW 111705
TXZ000-CWZ000-112300-
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 856
NWS STORM PREDICTION CENTER NORMAN OK
1205 PM CDT MON AUG 11 2003
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
SOUTHEAST TEXAS
COASTAL WATERS
EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 1205 PM UNTIL 600
PM CDT.
HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 60 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 50 MILES NORTHEAST OF HOUSTON TEXAS
TO 50 MILES NORTH NORTHWEST OF PALACIOS TEXAS.
REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES.
DISCUSSION...CLUSTER OF THUNDERSTORMS IS INCREASING NORTH OF
HOU...NEAR INTERSECTION OF OUTFLOW BOUNDARIES. THESE STORMS ARE
EXPECTED TO SPREAD SOUTHWARD TOWARD THE COAST THROUGH THE
AFTERNOON...POSSIBLY EXPANDING WESTWARD INTO VERY MOIST/UNSTABLE
AIRMASS. DAMAGING WINDS APPEAR TO BE THE MAIN THREAT.
AVIATION...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 36030.
...HART
291,0944 283,0963 301,0963 310,0944SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 11:31 AM CDT | Mesoscale Discussion | SPC | Austin, Bastrop, Brazoria, Brazos, Burleson, Caldwell and 27 more | 89 min |
| Aug 11, 2:06 PM CDT | Mesoscale Discussion | SPC | Bowie, Camp, Cass, Collin, Cooke, Dallas and 31 more | 54 min |
| Aug 11, 2:31 PM CDT | Mesoscale Discussion | SPC | Atascosa, Austin, Bandera, Bastrop, Bee, Bexar and 44 more | 29 min |
| Aug 11, 2:35 PM CDT | Severe Thunderstorm Watch | SPC | Atascosa, Bandera, Bastrop, Bee, Bexar, Blanco and 21 more | 5 hr |
| Aug 11, 4:45 PM CDT | Severe Thunderstorm Watch | SPC | Bosque, Clay, Collin, Comanche, Cooke, Dallas and 17 more | 5 hr |
| Aug 11, 5:16 PM CDT | Mesoscale Discussion | SPC | Anderson, Angelina, Austin, Brazoria, Brazos, Chambers and 21 more | 59 min |
| Aug 11, 5:29 PM CDT | Mesoscale Discussion | SPC | Collin, Dallas, Ellis, Grayson, Navarro, Rockwall | 2 hr |
| Aug 11, 6:09 PM CDT | Mesoscale Discussion | SPC | Aransas, Atascosa, Bandera, Bastrop, Bee, Bexar and 42 more | 96 min |
Nearby
Severe Thunderstorm Watches in Texas, 2003Every severe thunderstorm 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; radar from the NEXRAD Level II archive.