Alert archive / Louisiana / Mesoscale Discussions in 2017
Mesoscale Discussion 405
The Storm Prediction Center issued this mesoscale discussion at Apr 2, 2017, 3:08 PM CDT for 12 parishes in Louisiana; Amite County, Pike County, Walthall County, Mississippi. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 2, 2017, 3:08 PM CDT (20:08 UTC)
- Expired
- Apr 2, 2017, 5:45 PM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
Counties Ascension Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Livingston 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, Washington Parish, LA, West Feliciana Parish, LA, Amite County, MS, Pike County, MS, Walthall County, MS
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Slidell Radar S, LA (KSIL), launched 12:00Z, 8.1 hours before the alert went out and 96 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
- 269 J/kg
- Mixed-layer CIN
- -529 J/kg
- Mixed-layer LCL
- 1056 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 74 m²/s²
- 0-3 km storm-relative helicity
- 95 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.4
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 2, 9:04 AM CDT | Mesoscale Discussion | SPC | Beauregard, Sabine, Vernon | 2 hr |
| Apr 2, 9:05 AM CDT | Mesoscale Discussion | SPC | Acadia, Ascension, East Baton Rouge, Iberville, Lafayette, Livingston and 5 more | 85 min |
| Apr 2, 10:39 AM CDT | Tornado Watch | SPC | Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 13 more | 5 hr |
| Apr 2, 12:22 PM CDT | Mesoscale Discussion | SPC | Sabine | 83 min |
| Apr 2, 12:49 PM CDT | Mesoscale Discussion | SPC | Avoyelles, Concordia, East Baton Rouge, East Carroll, East Feliciana, Franklin and 7 more | 116 min |
| Apr 2, 1:34 PM CDT | Tornado Watch | SPC | Acadia, Allen, Avoyelles, Beauregard, Bienville, Calcasieu and 28 more | 7 hr |
| Apr 2, 2:06 PM CDT | Mesoscale Discussion | SPC | Grant, LaSalle, Natchitoches, Rapides, Sabine, Vernon and 1 more | 54 min |
| Apr 2, 3:13 PM CDT | Mesoscale Discussion | SPC | Allen, Avoyelles, Beauregard, Caldwell, Catahoula, Concordia and 13 more | 92 min |
| Apr 2, 4:52 PM CDT | Tornado Watch | SPC | Ascension, Concordia, East Baton Rouge, East Feliciana, Iberville, Livingston and 8 more | 9 hr |
| Apr 2, 5:54 PM CDT | Mesoscale Discussion | SPC | Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Catahoula and 7 more | 96 min |
| Apr 2, 3:31 PM CDT | Mesoscale Discussion | SPC | Carroll, Holmes, Humphreys, Leflore, Montgomery, Sunflower and 1 more | 29 min |
| Apr 2, 5:06 PM CDT | Mesoscale Discussion | SPC | Bolivar, Calhoun, Chickasaw, Coahoma, Grenada, Itawamba and 9 more | 84 min |
| Apr 2, 5:26 PM CDT | Severe Thunderstorm Watch | SPC | Calhoun, Chickasaw, Coahoma, Itawamba, Lafayette, Lee and 7 more | 3 hr |
Nearby
Mesoscale Discussions in Louisiana, 2017Mesoscale Discussions in Mississippi, 2017Every mesoscale discussion in 2017
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.