Alert archive / Louisiana / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 212
The Storm Prediction Center issued this severe thunderstorm watch at Apr 26, 2011, 1:52 AM CDT for 13 parishes in Louisiana; 10 counties in Texas. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 26, 2011, 1:52 AM CDT (06:52 UTC)
- Expired
- Apr 26, 2011, 7:00 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 23 counties
Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, Evangeline Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, Rapides Parish, LA, Saint Landry Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, Chambers County, TX, Hardin County, TX, Harris County, TX, Jasper County, TX, Jefferson County, TX, Liberty County, TX, Montgomery County, TX, Newton County, TX, Orange County, TX, Tyler County, TX
The radar
The Lake Charles radar (KLCH), 72 km from the middle of the area, began a volume at 06:54 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
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 26, 2:06 AM CDT | Severe Thunderstorm Warning | LCH | Beauregard, Calcasieu | 24 min |
| Apr 26, 2:17 AM CDT | Severe Thunderstorm Warning | LCH | Allen, Avoyelles, Evangeline, Rapides, Saint Landry | 58 min |
| Apr 26, 2:23 AM CDT | Severe Thunderstorm Warning | LCH | Hardin, Jasper, Tyler | 52 min |
| Apr 26, 2:35 AM CDT | Severe Thunderstorm Warning | LCH | Allen, Beauregard, Calcasieu, Jefferson Davis | 55 min |
| Apr 26, 2:56 AM CDT | Tornado Warning | LCH | Hardin | 34 min |
| Apr 26, 3:15 AM CDT | Severe Thunderstorm Warning | LCH | Avoyelles, Saint Landry | 45 min |
| Apr 26, 3:17 AM CDT | Severe Thunderstorm Warning | LCH | Calcasieu, Cameron | 58 min |
| Apr 26, 4:09 AM CDT | Severe Thunderstorm Warning | LCH | Calcasieu, Cameron | 66 min |
| Apr 26, 6:22 AM CDT | Severe Thunderstorm Warning | LCH | Vermilion | 53 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, 6.9 hours before the alert went out and 74 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
- 2759 J/kg
- Mixed-layer CIN
- 0 J/kg
- Mixed-layer LCL
- 581 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 86 m²/s²
- 0-3 km storm-relative helicity
- 133 m²/s²
- Significant tornado parameter
- 1.5
- Supercell composite
- 8.4
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 25, 7:34 PM CDT | Mesoscale Discussion | SPC | Bossier, Claiborne, Lincoln, Union, Webster | 116 min |
| Apr 25, 9:23 PM CDT | Tornado Watch | SPC | Caldwell, East Carroll, Franklin, Madison, Morehouse, Ouachita and 2 more | 7 hr |
| Apr 25, 9:37 PM CDT | Mesoscale Discussion | SPC | De Soto, Sabine | 83 min |
| Apr 25, 10:47 PM CDT | Tornado Watch | SPC | Allen, Beauregard, Evangeline, Rapides, Sabine, Vernon | 5 hr |
| Apr 25, 11:05 PM CDT | Mesoscale Discussion | SPC | East Carroll, Morehouse, West Carroll | 115 min |
| Apr 26, 1:34 AM CDT | Mesoscale Discussion | SPC | Allen, Beauregard, Calcasieu, Evangeline, Jefferson Davis, Rapides and 1 more | 86 min |
| Apr 26, 1:11 PM CDT | Mesoscale Discussion | SPC | Bienville, Bossier, Caddo, Claiborne, De Soto, Jackson and 5 more | 2 hr |
| Apr 26, 1:44 PM CDT | Tornado Watch | SPC | Bossier, Caddo, Claiborne, Union, Webster | 10 hr |
| Apr 26, 3:59 PM CDT | Mesoscale Discussion | SPC | Bossier, Caddo, Claiborne, Union, Webster | 91 min |
| Apr 26, 4:56 PM CDT | Tornado Watch | SPC | Beauregard, Bienville, Caldwell, De Soto, Grant, Jackson and 9 more | 5 hr |
| Apr 26, 6:43 PM CDT | Mesoscale Discussion | SPC | Beauregard, Bienville, Bossier, Caddo, Caldwell, Claiborne and 13 more | 2 hr |
| Apr 26, 3:01 PM CDT | Mesoscale Discussion | SPC | Atascosa, Austin, Bastrop, Bee, Bexar, Blanco and 22 more | 89 min |
| Apr 26, 3:15 PM CDT | Mesoscale Discussion | SPC | Archer, Baylor, Childress, Clay, Collingsworth, Cottle and 16 more | 90 min |
| Apr 26, 3:43 PM CDT | Severe Thunderstorm Watch | SPC | Archer, Baylor, Clay, Foard, Hardeman, Knox and 2 more | 6 hr |
Nearby
Severe Thunderstorm Watches in Louisiana, 2011Severe Thunderstorm Watches in Texas, 2011Every severe thunderstorm watch in 2011
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.