Alert archive / Alabama / Mesoscale Discussions in 2015

Mesoscale Discussion 186

April 2, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Apr 2, 2015, 1:57 PM CDT for 4 states. It was in force for 63 min.

The area

The outline as issued.

The facts

Issued: Apr 2, 2015, 1:57 PM CDT (18:57 UTC)
Expired: Apr 2, 2015, 3:00 PM CDT
In force: 63 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 59 counties

Blount County, AL, Calhoun County, AL, Cherokee County, AL, Colbert County, AL, Cullman County, AL, DeKalb County, AL, Etowah County, AL, Fayette County, AL, Franklin County, AL, Jackson County, AL, Jefferson County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL, Walker County, AL, Winston County, AL, Catoosa County, GA, Chattooga County, GA, Dade County, GA, Floyd County, GA, Walker County, GA, Alcorn County, MS, Itawamba County, MS, Lee County, MS, Monroe County, MS, Prentiss County, MS, Tishomingo County, MS, Bedford County, TN, Cannon County, TN, Coffee County, TN, Decatur County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Hamilton County, TN, Hardin County, TN, Hickman County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Marion County, TN, Marshall County, TN, Maury County, TN, McNairy County, TN, Moore County, TN, Perry County, TN, Rutherford County, TN, Sequatchie County, TN, Warren County, TN, Wayne County, TN, Williamson County, TN

The radar

The Northeast Alabama radar (KHTX), 69 km from the middle of the area, began a volume at 19:00 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

Nashville Metro, TN (KBNA), launched 12:00Z, 7.0 hours before the alert went out and 161 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: 114 J/kg
Mixed-layer CIN: -96 J/kg
Mixed-layer LCL: 1203 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 193 m²/s²
0-3 km storm-relative helicity: 202 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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
Apr 2, 11:50 AM CDT	Mesoscale Discussion	SPC	Crockett, Dyer, Gibson, Haywood, Lake, Lauderdale and 4 more	85 min
Apr 2, 5:03 PM CDT	Mesoscale Discussion	SPC	Clay, Davidson, Jackson, Macon, Robertson, Smith and 3 more	57 min

Nearby

Mesoscale Discussions in Alabama, 2015 Mesoscale Discussions in Tennessee, 2015 Mesoscale Discussions in Mississippi, 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.