Alert archive / Texas / Tornado Watches in 2009

Tornado Watch 63

March 25, 200942 counties in Texas

The Storm Prediction Center issued this tornado watch at Mar 25, 2009, 2:06 PM CDT for 42 counties in Texas. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Mar 25, 2009, 2:06 PM CDT (19:06 UTC)
Expired
Mar 25, 2009, 9:00 PM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
60 kt
All 42 counties

Anderson County, TX, Bandera County, TX, Bastrop County, TX, Bexar County, TX, Blanco County, TX, Brazos County, TX, Burleson County, TX, Burnet County, TX, Caldwell County, TX, Comal County, TX, Edwards County, TX, Fayette County, TX, Gillespie County, TX, Gonzales County, TX, Grimes County, TX, Guadalupe County, TX, Hays County, TX, Houston County, TX, Kendall County, TX, Kerr County, TX, Kimble County, TX, Kinney County, TX, Lee County, TX, Leon County, TX, Llano County, TX, Madison County, TX, Mason County, TX, Medina County, TX, Milam County, TX, Montgomery County, TX, Polk County, TX, Real County, TX, Robertson County, TX, San Jacinto County, TX, Sutton County, TX, Travis County, TX, Trinity County, TX, Uvalde County, TX, Val Verde County, TX, Walker County, TX, Washington County, TX, Williamson County, TX

The radar

The Austin/San Antonio radar (KEWX), 92 km from the middle of the area, began a volume at 19:07 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
60%
One or more EF2 to EF5 tornadoes
30%
Ten or more severe wind reports
50%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
70%
One or more hailstones of 2 inches or more
50%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Mar 25, 2:31 PM CDTSevere Thunderstorm WarningSJTKimble, Menard, Sutton44 min
Mar 25, 3:04 PM CDTSevere Thunderstorm WarningSJTKimble, Mason, Menard41 min
Mar 25, 3:15 PM CDTSevere Thunderstorm WarningSJTKimble15 min
Mar 25, 3:28 PM CDTSevere Thunderstorm WarningSJTMcCulloch, Mason, Menard47 min
Mar 25, 3:42 PM CDTSevere Thunderstorm WarningSJTMason48 min
Mar 25, 3:45 PM CDTSevere Thunderstorm WarningEWXGillespie, Llano60 min
Mar 25, 3:49 PM CDTTornado WarningSJTMason26 min
Mar 25, 4:00 PM CDTTornado WarningEWXLlano45 min
Mar 25, 4:05 PM CDTSevere Thunderstorm WarningSJTKimble25 min
Mar 25, 4:37 PM CDTSevere Thunderstorm WarningEWXBlanco, Burnet, Llano38 min
Mar 25, 4:48 PM CDTTornado WarningEWXBlanco, Burnet, Llano42 min
Mar 25, 4:59 PM CDTSevere Thunderstorm WarningEWXBlanco, Burnet, Travis, Williamson46 min
Mar 25, 5:18 PM CDTSevere Thunderstorm WarningEWXBlanco, Gillespie, Kendall42 min
Mar 25, 5:35 PM CDTSevere Thunderstorm WarningEWXTravis, Williamson55 min
Mar 25, 6:11 PM CDTSevere Thunderstorm WarningEWXBastrop, Lee, Travis, Williamson40 min
Mar 25, 6:38 PM CDTSevere Thunderstorm WarningHGXBrazos, Burleson, Washington37 min
Mar 25, 6:56 PM CDTSevere Thunderstorm WarningHGXWashington49 min
Mar 25, 7:15 PM CDTSevere Thunderstorm WarningHGXBrazos, Grimes, Washington30 min
Mar 25, 7:22 PM CDTSevere Thunderstorm WarningHGXPolk, Trinity38 min
Mar 25, 7:40 PM CDTTornado WarningHGXGrimes, Montgomery, San Jacinto, Walker50 min
Mar 25, 8:10 PM CDTTornado WarningHGXHarris, Montgomery50 min
Mar 25, 8:25 PM CDTTornado WarningHGXHarris, Liberty, Montgomery, San Jacinto50 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

Del Rio, TX (KDRT), launched 12:00Z, 7.1 hours before the alert went out and 249 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, Del Rio, TX at 12:00Z on 2009-03-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1215 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Del Rio, TX at 12:00Z on 2009-03-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 149 square meters per square second.1939587897Sfc1 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
1215 J/kg
Mixed-layer CIN
-75 J/kg
Mixed-layer LCL
976 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
149 m²/s²
0-3 km storm-relative helicity
223 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.4

Open this sounding in Storm Lab

The text

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

246 
WWUS20 KWNS 251909
SEL3  
SPC WW 251909
TXZ000-260200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 63
NWS STORM PREDICTION CENTER NORMAN OK
205 PM CDT WED MAR 25 2009

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

       CENTRAL AND SOUTHEAST TEXAS

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 205 PM UNTIL
900 PM CDT.

TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 30 MILES NORTH OF DEL RIO
TEXAS TO 30 MILES EAST NORTHEAST OF HUNTSVILLE TEXAS.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU3).

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 62...

DISCUSSION...SURFACE-BASED THUNDERSTORMS ARE BEGINNING TO DEVELOP
ALONG THE NW EDGE OF THE SURFACE WARM SECTOR BETWEEN DRT AND SJT. 
THESE STORMS WILL LIKELY INCREASE IN COVERAGE/INTENSITY THROUGH THE
AFTERNOON AS A MID LEVEL SPEED MAX EJECTS EWD FROM THE BIG
BEND...AND A SURFACE WARM FRONT LIFTS SLOWLY NWD ACROSS S CENTRAL
AND SE TX.  MODERATE INSTABILITY /MLCAPE AOA 1500 J/KG/ AND
EFFECTIVE BULK SHEAR IN EXCESS OF 50 KT WILL FAVOR SUPERCELLS
CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING WINDS.  LOW-LEVEL
FLOW/SHEAR WILL GRADUALLY INCREASE THROUGH THE AFTERNOON ACROSS
CENTRAL/SE TX IN ADVANCE OF THE EJECTING MID LEVEL SPEED MAX...THUS
SUPPORTING A THREAT FOR TORNADOES WITH STORMS ALONG THE WARM FRONT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 26030.


...THOMPSON

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 24, 7:30 PM CDTMesoscale DiscussionSPCAngelina, Nacogdoches, Sabine, San Augustine, Shelby2 hr
Mar 24, 11:25 PM CDTTornado WatchSPCJasper, Newton, Sabine, San Augustine, Tyler5 hr
Mar 25, 10:55 AM CDTMesoscale DiscussionSPCAnderson, Bell, Blanco, Bosque, Brown, Burleson and 40 more65 min
Mar 25, 11:27 AM CDTSevere Thunderstorm WatchSPCBell, Bosque, Brown, Callahan, Coke, Coleman and 47 more7 hr
Mar 25, 12:51 PM CDTMesoscale DiscussionSPCAtascosa, Austin, Bandera, Bastrop, Bexar, Blanco and 48 more114 min
Mar 25, 1:48 PM CDTMesoscale DiscussionSPCBosque, Brown, Callahan, Coleman, Collin, Comanche and 31 more87 min
Mar 25, 2:42 PM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Delta, Franklin, Gregg and 11 more93 min
Mar 25, 3:47 PM CDTMesoscale DiscussionSPCCoryell, Ellis, Falls, Freestone, Henderson, Hill and 8 more88 min
Mar 25, 3:57 PM CDTMesoscale DiscussionSPCBandera, Bastrop, Bexar, Blanco, Brazos, Burleson and 31 more93 min
Mar 25, 5:29 PM CDTMesoscale DiscussionSPCAngelina, Brazos, Burleson, Grimes, Houston, Jasper and 15 more91 min
Mar 25, 5:40 PM CDTTornado WatchSPCAngelina, Cherokee, Gregg, Harrison, Jasper, Marion and 8 more6 hr

Nearby

Tornado Watches in Texas, 2009Every tornado watch in 2009

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.