Alert archive / Mississippi / Mesoscale Discussions in 2017
Mesoscale Discussion 611
The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2017, 6:59 AM CDT for 18 parishes in Louisiana; 56 counties in Mississippi. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 30, 2017, 6:59 AM CDT (11:59 UTC)
- Expired
- Apr 30, 2017, 9:00 AM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 80%
All 74 counties
Ascension Parish, LA, Assumption Parish, LA, East Baton Rouge Parish, LA, East Feliciana 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, Amite County, MS, Attala County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Clarke County, MS, Clay County, MS, Copiah County, MS, Covington County, MS, Forrest County, MS, Franklin County, MS, George County, MS, Greene County, MS, Grenada County, MS, Hancock County, MS, Harrison County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Jackson County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lamar County, MS, Lauderdale County, MS, Lawrence County, MS, Leake County, MS, Leflore County, MS, Lincoln County, MS, Lowndes County, MS, Madison County, MS, Marion County, MS, Monroe County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Sunflower County, MS, Tallahatchie County, MS, Walthall County, MS, Wayne County, MS, Webster County, MS, Winston County, MS, Yalobusha County, MS, Yazoo County, MS
The radar
The Jackson/Brandon,MS radar (KDGX), 107 km from the middle of the area, began a volume at 12:03 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.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Jackson, MS (KJAN), launched 00:00Z, 12.0 hours before the alert went out and 113 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
- 1340 J/kg
- Mixed-layer CIN
- -32 J/kg
- Mixed-layer LCL
- 1169 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 170 m²/s²
- 0-3 km storm-relative helicity
- 258 m²/s²
- Significant tornado parameter
- 1.0
- Supercell composite
- 10.9
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 29, 9:38 PM CDT | Mesoscale Discussion | SPC | Bossier, Caddo, De Soto, Sabine, Webster | 67 min |
| Apr 29, 10:23 PM CDT | Severe Thunderstorm Watch | SPC | Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more | 8 hr |
| Apr 29, 11:37 PM CDT | Mesoscale Discussion | SPC | Bienville, Bossier, Caddo, Claiborne, De Soto, Lincoln and 5 more | 53 min |
| Apr 30, 1:14 AM CDT | Mesoscale Discussion | SPC | Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Caldwell and 20 more | 91 min |
| Apr 30, 1:49 AM CDT | Tornado Watch | SPC | Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Cameron and 21 more | 7 hr |
| Apr 30, 3:36 AM CDT | Mesoscale Discussion | SPC | Caldwell, Grant, Jackson, LaSalle, Lincoln, Natchitoches and 3 more | 84 min |
| Apr 30, 5:41 AM CDT | Mesoscale Discussion | SPC | Union | 64 min |
| Apr 30, 6:12 AM CDT | Mesoscale Discussion | SPC | Acadia, Avoyelles, Concordia, East Baton Rouge, East Carroll, East Feliciana and 16 more | 93 min |
| Apr 30, 7:32 AM CDT | Tornado Watch | SPC | Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 14 more | 7 hr |
| Apr 30, 12:54 AM CDT | Mesoscale Discussion | SPC | Bolivar, Coahoma, DeSoto, Panola, Quitman, Sunflower and 3 more | 96 min |
| Apr 30, 1:10 AM CDT | Severe Thunderstorm Watch | SPC | DeSoto, Tunica | 6 hr |
| Apr 30, 2:58 AM CDT | Mesoscale Discussion | SPC | DeSoto, Marshall, Tate, Tunica | 92 min |
| Apr 30, 10:06 AM CDT | Mesoscale Discussion | SPC | Chickasaw, Itawamba, Lee, Monroe, Pontotoc, Prentiss and 2 more | 84 min |
| Apr 30, 10:36 AM CDT | Tornado Watch | SPC | Alcorn, Benton, Calhoun, Chickasaw, Itawamba, Lafayette and 9 more | 8 hr |
Nearby
Mesoscale Discussions in Mississippi, 2017Mesoscale Discussions in Louisiana, 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; radar from the NEXRAD Level II archive.