Alert archive / Louisiana / Severe Thunderstorm Watches in 2007

Severe Thunderstorm Watch 422

June 19, 2007Mobile County, Alabama; 22 parishes in Louisiana; 10 counties in Mississippi

The Storm Prediction Center issued this severe thunderstorm watch at Jun 19, 2007, 3:21 PM CDT for Mobile County, Alabama; 22 parishes in Louisiana; 10 counties in Mississippi. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jun 19, 2007, 3:21 PM CDT (20:21 UTC)
Expired
Jun 19, 2007, 9:00 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 33 counties

Mobile County, AL, Ascension Parish, LA, Assumption Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Jefferson Parish, LA, Lafourche Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Plaquemines Parish, LA, Pointe Coupee Parish, LA, Saint Bernard Parish, LA, Saint Charles Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Terrebonne Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Amite County, MS, George County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Pearl River County, MS, Pike County, MS, Stone County, MS, Walthall County, MS, Wilkinson County, MS

What SPC expected

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

Two or more tornadoes
10%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
50%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
20%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jun 19, 4:08 PM CDTSevere Thunderstorm WarningLIXAmite, Pike, Walthall, Wilkinson67 min
Jun 19, 4:12 PM CDTSevere Thunderstorm WarningMOBMobile, Washington63 min
Jun 19, 4:18 PM CDTSevere Thunderstorm WarningLIXPearl River42 min
Jun 19, 4:33 PM CDTSevere Thunderstorm WarningMOBStone27 min
Jun 19, 4:39 PM CDTFlash Flood WarningMOBMobile2 hr
Jun 19, 4:39 PM CDTSevere Thunderstorm WarningLIXSaint Helena, Tangipahoa51 min
Jun 19, 4:45 PM CDTSevere Thunderstorm WarningLIXSaint Tammany60 min
Jun 19, 4:49 PM CDTSevere Thunderstorm WarningLIXWashington41 min
Jun 19, 6:03 PM CDTSevere Thunderstorm WarningLIXJefferson, Orleans, Plaquemines, Saint Bernard, Saint Charles, Saint John the Baptist57 min
Jun 19, 7:19 PM CDTTornado WarningLIXAssumption26 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

Slidell Radar S, LA (KSIL), launched 12:00Z, 8.4 hours before the alert went out and 80 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, Slidell Radar S, LA at 12:00Z on 2007-06-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2132 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, Slidell Radar S, LA at 12:00Z on 2007-06-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 71 square meters per square second.193958Sfc1 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
2132 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
595 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
71 m²/s²
0-3 km storm-relative helicity
129 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 19, 12:15 PM CDTMesoscale DiscussionSPCAutauga, Barbour, Bullock, Butler, Chambers, Clarke and 20 more60 min
Jun 19, 10:17 AM CDTMesoscale DiscussionSPCEast Carroll, Franklin, Madison, Morehouse, Richland, Tensas and 1 more28 min
Jun 19, 10:39 AM CDTSevere Thunderstorm WatchSPCCatahoula, Concordia, East Carroll, Franklin, Madison, Morehouse and 3 more6 hr
Jun 19, 12:55 PM CDTMesoscale DiscussionSPCEast Carroll, Franklin, Madison, Morehouse, Richland, Tensas and 1 more65 min
Jun 19, 3:07 PM CDTMesoscale DiscussionSPCAscension, Assumption, Concordia, East Baton Rouge, East Carroll, East Feliciana and 26 more53 min
Jun 19, 3:41 PM CDTMesoscale DiscussionSPCMorehouse, Union64 min

Nearby

Severe Thunderstorm Watches in Louisiana, 2007Severe Thunderstorm Watches in Mississippi, 2007Severe Thunderstorm Watches in Alabama, 2007Every severe thunderstorm watch in 2007

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.