Alert archive / Louisiana / Severe Thunderstorm Watches in 2013
Severe Thunderstorm Watch 40
The Storm Prediction Center issued this severe thunderstorm watch at Feb 25, 2013, 12:04 AM CST for 20 parishes in Louisiana; 4 counties in Mississippi. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 25, 2013, 12:04 AM CST (06:04 UTC)
- Expired
- Feb 25, 2013, 7:49 AM CST
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 24 counties
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, 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, Hancock County, MS, Harrison County, MS, Jackson County, MS, Pearl River County, MS
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
8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 25, 12:22 AM CST | Severe Thunderstorm Warning | LIX | Jackson | 23 min |
| Feb 25, 12:29 AM CST | Severe Thunderstorm Warning | LIX | Saint Tammany, Tangipahoa | 46 min |
| Feb 25, 2:40 AM CST | Severe Thunderstorm Warning | LIX | Harrison, Jackson | 35 min |
| Feb 25, 3:11 AM CST | Severe Thunderstorm Warning | LIX | Ascension, Livingston, Saint James, Saint John the Baptist | 34 min |
| Feb 25, 3:17 AM CST | Severe Thunderstorm Warning | LIX | Harrison, Jackson | 43 min |
| Feb 25, 3:28 AM CST | Severe Thunderstorm Warning | LIX | Jackson | 62 min |
| Feb 25, 3:42 AM CST | Severe Thunderstorm Warning | LIX | Livingston, Saint John the Baptist, Saint Tammany, Tangipahoa | 33 min |
| Feb 25, 4:15 AM CST | Flash Flood Warning | LIX | Saint Tammany | 3 hr |
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 00:00Z, 6.1 hours before the alert went out and 50 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 902 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 53 m²/s²
- 0-3 km storm-relative helicity
- 160 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.6
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 24, 6:48 PM CST | Mesoscale Discussion | SPC | Ascension, Assumption, Iberia, Iberville, Jefferson, Lafourche and 10 more | 87 min |
| Feb 24, 11:57 PM CST | Mesoscale Discussion | SPC | Ascension, Assumption, Iberia, Jefferson, Lafourche, Livingston and 9 more | 63 min |
| Feb 25, 2:50 AM CST | Mesoscale Discussion | SPC | Jefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 3 more | 115 min |
| Feb 25, 9:07 AM CST | Mesoscale Discussion | SPC | Plaquemines, Saint Bernard | 2 hr |
| Feb 25, 9:25 AM CST | Mesoscale Discussion | SPC | Acadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 56 more | 65 min |
| Feb 25, 12:26 PM CST | Tornado Watch | SPC | Acadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 58 more | 10 hr |
| Feb 25, 2:15 PM CST | Mesoscale Discussion | SPC | Acadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 53 more | 90 min |
| Feb 25, 2:52 PM CST | Mesoscale Discussion | SPC | Saint Bernard | 83 min |
| Feb 25, 3:54 PM CST | Tornado Watch | SPC | Attala, Bolivar, Carroll, Choctaw, Clarke, Clay and 32 more | 6 hr |
Nearby
Severe Thunderstorm Watches in Louisiana, 2013Severe Thunderstorm Watches in Mississippi, 2013Every severe thunderstorm watch in 2013
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.