Alert archive / Texas / Tornado Watches in 2008

Tornado Watch 29

January 31, 200816 parishes in Louisiana; 18 counties in Texas

The Storm Prediction Center issued this tornado watch at Jan 31, 2008, 5:51 AM CST for 16 parishes in Louisiana; 18 counties in Texas. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Jan 31, 2008, 5:51 AM CST (11:51 UTC)
Expired
Jan 31, 2008, 12:41 PM CST
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 34 counties

Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, Evangeline Parish, LA, Iberia Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, Rapides Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, St. Mary Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, Brazoria County, TX, Chambers County, TX, Fort Bend County, TX, Galveston County, TX, Hardin County, TX, Harris County, TX, Jackson County, TX, Jasper County, TX, Jefferson County, TX, Liberty County, TX, Matagorda County, TX, Montgomery County, TX, Newton County, TX, Orange County, TX, Polk County, TX, San Jacinto County, TX, Tyler County, TX, Wharton County, TX

The radar

The Lake Charles radar (KLCH), 57 km from the middle of the area, began a volume at 11:53 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
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jan 31, 7:43 AM CSTSevere Thunderstorm WarningHGXSan Jacinto, Walker47 min
Jan 31, 8:32 AM CSTSevere Thunderstorm WarningHGXHarris, Liberty, Montgomery, San Jacinto28 min
Jan 31, 8:54 AM CSTSevere Thunderstorm WarningHGXHarris, Liberty, Montgomery, Polk, San Jacinto51 min
Jan 31, 9:23 AM CSTSevere Thunderstorm WarningLCHHardin, Tyler52 min
Jan 31, 9:48 AM CSTSevere Thunderstorm WarningHGXChambers, Harris, Liberty27 min
Jan 31, 10:05 AM CSTSevere Thunderstorm WarningLCHBeauregard, Calcasieu40 min
Jan 31, 10:29 AM CSTSevere Thunderstorm WarningLCHCalcasieu31 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, 11.9 hours before the alert went out and 59 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, Lake Charles Mun, LA at 00:00Z on 2008-01-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Lake Charles Mun, LA at 00:00Z on 2008-01-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 130 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2503 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
130 m²/s²
0-3 km storm-relative helicity
203 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000
WWUS20 KWNS 311156
SEL9  
SPC WW 311156
LAZ000-TXZ000-CWZ000-311900-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 29
NWS STORM PREDICTION CENTER NORMAN OK
550 AM CST THU JAN 31 2008

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

       SOUTHWEST AND SOUTH CENTRAL LOUISIANA
       SOUTHEAST TEXAS
       COASTAL WATERS

EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON FROM 550 AM UNTIL
100 PM CST.

TORNADOES...HAIL TO 1.5 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 115 STATUTE
MILES EAST AND WEST OF A LINE FROM 65 MILES NORTH NORTHEAST OF
LAKE CHARLES LOUISIANA TO 35 MILES SOUTHEAST OF GALVESTON TEXAS. 
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU9).

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...TSTMS EXPECTED TO INCREASE IN NUMBER AND STRENGTH IN
WAA ZONE INVOF NW GULF OF MEXICO SFC WAVE.  OTHER STORMS EXPECTED TO
INTENSIFY FARTHER NW ALONG LEADING EDGE OF ASCENT ASSOCIATED WITH
STRONG TX PANHANDLE UPR VORT.  VERY SHALLOW LAYER OF POLAR AIR NOW
OVER WW REGION EXPECTED TO ERODE STEADILY NWD THROUGH
MIDDAY...INCREASING CHANCES THAT STORMS IN THE NW GULF AND SE TX
WILL BECOME MORE NEARLY SFC-BASED AS THEY MOVE/DEVELOP NE INTO LA. 
GIVEN STRENGTH OF WIND FIELD AND CONSIDERABLE SPEED/DIRECTIONAL
SHEAR...RESULTING SUPERCELLS COULD PRODUCE TORNADOES IN ADDITION TO
HIGH WIND AND HAIL.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
400. MEAN STORM MOTION VECTOR 22040.


...CORFIDI

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 30, 11:47 PM CSTMesoscale DiscussionSPCBossier, Caddo, De Soto, Sabine2 hr
Jan 31, 5:23 AM CSTMesoscale DiscussionSPCBeauregard, Calcasieu, Cameron3 hr
Jan 31, 9:57 AM CSTMesoscale DiscussionSPCCameron2 hr
Jan 31, 12:06 PM CSTMesoscale DiscussionSPCAscension, Assumption, East Baton Rouge, Iberia, Iberville, Jefferson and 15 more54 min
Jan 31, 12:35 PM CSTTornado WatchSPCAscension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 22 more6 hr
Jan 31, 3:25 PM CSTMesoscale DiscussionSPCAscension, Assumption, Livingston, Orleans, Saint Bernard, Saint Charles and 5 more95 min

Nearby

Tornado Watches in Texas, 2008Tornado Watches in Louisiana, 2008Every tornado watch in 2008

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.