Alert archive / Georgia / Mesoscale Discussions in 2015

Mesoscale Discussion 383

April 19, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2015, 5:25 PM CDT for 4 states. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: Apr 19, 2015, 5:25 PM CDT (22:25 UTC)
Expired: Apr 19, 2015, 7:00 PM CDT
In force: 95 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 39 counties

Calhoun County, AL, Cherokee County, AL, Cleburne County, AL, DeKalb County, AL, Etowah County, AL, Bartow County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Cobb County, GA, Dade County, GA, Dawson County, GA, Douglas County, GA, Fannin County, GA, Floyd County, GA, Gilmer County, GA, Gordon County, GA, Haralson County, GA, Lumpkin County, GA, Murray County, GA, Paulding County, GA, Pickens County, GA, Polk County, GA, Union County, GA, Walker County, GA, Whitfield County, GA, Cherokee County, NC, Bledsoe County, TN, Bradley County, TN, Hamilton County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Polk County, TN, Rhea County, TN, Sequatchie County, TN, Van Buren County, TN

The radar

The Northeast Alabama radar (KHTX), 100 km from the middle of the area, began a volume at 22:27 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, 10.4 hours before the alert went out and 133 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: 239 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 617 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 207 m²/s²
0-3 km storm-relative helicity: 329 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.9

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 19, 2:06 AM CDT	Mesoscale Discussion	SPC	Choctaw, Clarke, Marengo, Washington	84 min
Apr 19, 5:51 AM CDT	Mesoscale Discussion	SPC	Autauga, Baldwin, Barbour, Bullock, Butler, Coffee and 17 more	114 min
Apr 19, 6:57 AM CDT	Tornado Watch	SPC	Barbour, Bullock, Butler, Chambers, Clay, Coffee and 16 more	7 hr
Apr 19, 1:14 PM CDT	Mesoscale Discussion	SPC	Autauga, Bibb, Blount, Calhoun, Chambers, Cherokee and 36 more	2 hr
Apr 19, 9:40 AM CDT	Mesoscale Discussion	SPC	Bleckley, Calhoun, Crisp, Dodge, Dooly, Dougherty and 11 more	2 hr
Apr 19, 11:24 AM CDT	Mesoscale Discussion	SPC	Appling, Atkinson, Bacon, Ben Hill, Berrien, Brantley and 46 more	2 hr
Apr 19, 12:04 PM CDT	Tornado Watch	SPC	Appling, Atkinson, Bacon, Brantley, Bryan, Bulloch and 33 more	7 hr
Apr 19, 3:11 PM CDT	Mesoscale Discussion	SPC	Anson, Cabarrus, Catawba, Cleveland, Davie, Gaston and 7 more	2 hr
Apr 19, 4:01 PM CDT	Tornado Watch	SPC	Anson, Bladen, Brunswick, Chatham, Columbus, Cumberland and 16 more	6 hr
Apr 19, 6:11 PM CDT	Mesoscale Discussion	SPC	Bladen, Brunswick, Columbus, Craven, Cumberland, Duplin and 12 more	94 min

Nearby

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