Alert archive / Alabama / Mesoscale Discussions in 2015

Mesoscale Discussion 2057

December 24, 20158 counties in Alabama; 7 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Dec 24, 2015, 7:07 AM CST for 8 counties in Alabama; 7 counties in Georgia. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued: Dec 24, 2015, 7:07 AM CST (13:07 UTC)
Expired: Dec 24, 2015, 8:30 AM CST
In force: 83 min
Issued by: the Storm Prediction Center

Counties Barbour County, AL, Bullock County, AL, Coffee County, AL, Covington County, AL, Dale County, AL, Henry County, AL, Pike County, AL, Russell County, AL, Chattahoochee County, GA, Clay County, GA, Marion County, GA, Muscogee County, GA, Quitman County, GA, Randolph County, GA, Stewart County, GA

The radar

The Ft Rucker radar (KEOX), 46 km from the middle of the area, began a volume at 13:06 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

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 1.1 hours before the alert went out and 193 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: 468 J/kg
Mixed-layer CIN: -144 J/kg
Mixed-layer LCL: 864 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 269 m²/s²
0-3 km storm-relative helicity: 321 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 8.3

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
Dec 23, 6:35 PM CST	Mesoscale Discussion	SPC	Colbert, Franklin, Lauderdale, Lawrence, Limestone, Madison and 1 more	55 min
Dec 23, 7:41 PM CST	Mesoscale Discussion	SPC	Bibb, Fayette, Greene, Hale, Jefferson, Lamar and 8 more	2 hr
Dec 23, 8:20 PM CST	Tornado Watch	SPC	Bibb, Fayette, Greene, Hale, Jefferson, Lamar and 7 more	8 hr
Dec 23, 10:11 PM CST	Mesoscale Discussion	SPC	Blount, Calhoun, Cherokee, Cullman, DeKalb, Etowah and 12 more	2 hr
Dec 23, 10:33 PM CST	Tornado Watch	SPC	Cullman, DeKalb, Jackson, Lawrence, Limestone, Madison and 2 more	5 hr
Dec 24, 3:10 AM CST	Mesoscale Discussion	SPC	Autauga, Barbour, Bullock, Butler, Chambers, Coffee and 19 more	2 hr
Dec 24, 3:27 AM CST	Mesoscale Discussion	SPC	Bibb, Blount, Calhoun, Chambers, Cherokee, Chilton and 16 more	93 min
Dec 24, 4:09 AM CST	Tornado Watch	SPC	Barbour, Bullock, Coffee, Dale, Geneva, Henry and 5 more	7 hr

Nearby

Mesoscale Discussions in Alabama, 2015 Mesoscale Discussions in Georgia, 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.