Alert archive / Mississippi / Mesoscale Discussions in 2015

Mesoscale Discussion 756

May 25, 20154 counties in Alabama; Orleans Parish, Saint Tammany Parish, Washington Parish, Louisiana; 19 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at May 25, 2015, 2:38 AM CDT for 4 counties in Alabama; Orleans Parish, Saint Tammany Parish, Washington Parish, Louisiana; 19 counties in Mississippi. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: May 25, 2015, 2:38 AM CDT (07:38 UTC)
Expired: May 25, 2015, 5:15 AM CDT
In force: 3 hr
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 26 counties

Choctaw County, AL, Mobile County, AL, Sumter County, AL, Washington County, AL, Orleans Parish, LA, Saint Tammany Parish, LA, Washington Parish, LA, Clarke County, MS, Covington County, MS, Forrest County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Jasper County, MS, Jones County, MS, Kemper County, MS, Lamar County, MS, Lauderdale County, MS, Marion County, MS, Pearl River County, MS, Perry County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS

The radar

The Mobile radar (KMOB), 109 km from the middle of the area, began a volume at 07:42 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 nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 7.6 hours before the alert went out and 151 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 705 J/kg
Mixed-layer CIN: -20 J/kg
Mixed-layer LCL: 949 m above ground
0-6 km bulk shear: 0 kt
0-1 km storm-relative helicity: 0 m²/s²
0-3 km storm-relative helicity: 0 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 25, 9:00 AM CDT	Mesoscale Discussion	SPC	Colbert, Cullman, Franklin, Lauderdale, Lawrence, Limestone and 4 more	60 min
May 24, 7:42 PM CDT	Mesoscale Discussion	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 18 more	93 min
May 25, 5:15 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	90 min
May 25, 5:51 PM CDT	Tornado Watch	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	6 hr
May 25, 6:06 PM CDT	Mesoscale Discussion	SPC	Allen, Beauregard, Calcasieu, Cameron	54 min
May 25, 6:24 PM CDT	Tornado Watch	SPC	Acadia, Allen, Beauregard, Calcasieu, Cameron, Evangeline and 3 more	9 hr
May 24, 8:41 PM CDT	Mesoscale Discussion	SPC	Benton, Marshall, Tippah, Union	64 min

Nearby

Mesoscale Discussions in Mississippi, 2015 Mesoscale Discussions in Alabama, 2015 Mesoscale Discussions in Louisiana, 2015 Every mesoscale discussion in 2015

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.