Alert archive / Texas / Tornado Watches in 2003
Tornado Watch 10
The Storm Prediction Center issued this tornado watch at Feb 21, 2003, 4:25 AM CST for 21 counties in Texas. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 21, 2003, 4:25 AM CST (10:25 UTC)
- Expired
- Feb 21, 2003, 10:00 AM CST
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
All 21 counties
Austin County, TX, Brazoria County, TX, Brazos County, TX, Burleson County, TX, Calhoun County, TX, Colorado County, TX, Fayette County, TX, Fort Bend County, TX, Grimes County, TX, Harris County, TX, Jackson County, TX, Lavaca County, TX, Liberty County, TX, Matagorda County, TX, Montgomery County, TX, Refugio County, TX, San Jacinto County, TX, Victoria County, TX, Waller County, TX, Washington County, TX, Wharton County, TX
The radar
The Houston radar (KHGX), 129 km from the middle of the area, began a volume at 10:28 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
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 21, 4:53 AM CST | Severe Thunderstorm Warning | HGX | Jackson | 22 min |
| Feb 21, 5:15 AM CST | Severe Thunderstorm Warning | HGX | Jackson, Wharton | 45 min |
| Feb 21, 6:51 AM CST | Severe Thunderstorm Warning | HGX | Polk, San Jacinto | 39 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
Corpus Christi, TX (KCRP), launched 00:00Z, 10.4 hours before the alert went out and 190 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
- 962 J/kg
- Mixed-layer CIN
- -35 J/kg
- Mixed-layer LCL
- 623 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 98 m²/s²
- 0-3 km storm-relative helicity
- 140 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 2.7
The text
As transmitted, in the capitals the NWS used until 2016.
152 WWUS20 KWNS 211026 SEL0 SPC WW 211025 TXZ000-CWZ000-211600- URGENT - IMMEDIATE BROADCAST REQUESTED TORNADO WATCH NUMBER 10 STORM PREDICTION CENTER NORMAN OK 425 AM CST FRI FEB 21 2003 THE STORM PREDICTION CENTER HAS ISSUED A TORNADO WATCH FOR PORTIONS OF SOUTHEAST TEXAS AND ADJACENT COASTAL WATERS EFFECTIVE THIS FRIDAY MORNING FROM 425 AM UNTIL 1000 AM CST. 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 EAST AND WEST OF A LINE FROM 40 MILES SOUTH SOUTHWEST OF PALACIOS TEXAS TO 45 MILES EAST NORTHEAST 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 9... DISCUSSION...ISOLATED STRONG THUNDERSTORMS ARE INCREASING OVER SOUTHEAST TX AS LOW LEVEL JET STRENGTHENS. THESE STORMS MAY PRODUCE LARGE HAIL DURING THE NEXT FEW HOURS. SURFACE LOW DEEPENING OFF THE COAST NEAR CRP IS FORECAST TO TRACK NORTHWARD...BRINGING WARM SECTOR ONSHORE DURING THE NEXT SEVERAL HOURS. VERTICAL SHEAR PROFILES AND INCREASING INSTABILITY INDICATE THE POTENTIAL FOR ISOLATED TORNADOES BY MID MORNING. 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 24035. ...HART 281,0973 304,0964 304,0943 281,0952
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 21, 1:43 AM CST | Mesoscale Discussion | SPC | Chambers, Hardin, Jasper, Jefferson, Liberty, Newton and 1 more | 2 hr |
| Feb 21, 2:43 AM CST | Mesoscale Discussion | SPC | Dimmit, Edwards, Frio, Kinney, La Salle, Maverick and 5 more | 3 hr |
| Feb 21, 3:53 AM CST | Mesoscale Discussion | SPC | Aransas, Austin, Brazoria, Calhoun, Colorado, Fort Bend and 13 more | 3 hr |
| Feb 21, 4:10 AM CST | Severe Thunderstorm Watch | SPC | Atascosa, Bandera, Bastrop, Bexar, Blanco, Brazos and 26 more | 6 hr |
| Feb 21, 5:58 AM CST | Mesoscale Discussion | SPC | Atascosa, Bandera, Bastrop, Bexar, Blanco, Brazos and 26 more | 2 hr |
| Feb 21, 6:16 AM CST | Mesoscale Discussion | SPC | Austin, Brazoria, Brazos, Burleson, Calhoun, Colorado and 17 more | 119 min |
| Feb 21, 9:02 AM CST | Mesoscale Discussion | SPC | Angelina, Brazoria, Chambers, Cherokee, Fort Bend, Galveston and 22 more | 58 min |
| Feb 21, 9:40 AM CST | Tornado Watch | SPC | Angelina, Austin, Brazoria, Brazos, Burleson, Chambers and 25 more | 6 hr |
| Feb 21, 11:47 AM CST | Mesoscale Discussion | SPC | Angelina, Brazoria, Chambers, Fort Bend, Galveston, Grimes and 18 more | 118 min |
| Feb 21, 1:30 PM CST | Mesoscale Discussion | SPC | Hardin, Harris, Jasper, Liberty, Montgomery, Newton and 3 more | 2 hr |
| Feb 21, 3:32 PM CST | Mesoscale Discussion | SPC | Hardin, Jasper, Liberty, Newton, Orange, Tyler | 118 min |
| Feb 21, 3:40 PM CST | Tornado Watch | SPC | Angelina, Chambers, Hardin, Jasper, Jefferson, Nacogdoches and 5 more | 6 hr |
| Feb 21, 5:50 PM CST | Mesoscale Discussion | SPC | Angelina, Chambers, Hardin, Jasper, Jefferson, Nacogdoches and 5 more | 115 min |
Nearby
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.