Alert archive / Alabama / Mesoscale Discussions in 2024

Mesoscale Discussion 1949

August 18, 202427 counties in Alabama; 16 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Aug 18, 2024, 5:19 PM CDT for 27 counties in Alabama; 16 counties in Georgia. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued: Aug 18, 2024, 5:19 PM CDT (22:19 UTC)
Expired: Aug 18, 2024, 7:15 PM CDT
In force: 116 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 636

All 43 counties

Autauga County, AL, Barbour County, AL, Bibb County, AL, Bullock County, AL, Butler County, AL, Chambers County, AL, Chilton County, AL, Clarke County, AL, Coffee County, AL, Coosa County, AL, Crenshaw County, AL, Dale County, AL, Dallas County, AL, Elmore County, AL, Hale County, AL, Henry County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Marengo County, AL, Monroe County, AL, Montgomery County, AL, Perry County, AL, Pike County, AL, Russell County, AL, Tallapoosa County, AL, Wilcox County, AL, Calhoun County, GA, Chattahoochee County, GA, Clay County, GA, Dougherty County, GA, Harris County, GA, Lee County, GA, Marion County, GA, Muscogee County, GA, Quitman County, GA, Randolph County, GA, Schley County, GA, Stewart County, GA, Sumter County, GA, Terrell County, GA, Webster County, GA, Worth County, GA

The radar

The Maxwell AFB radar (KMXX), 43 km from the middle of the area, began a volume at 22:22 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.

Severe Thunderstorm Watch 638Aug 18, 6:10 PM CDT

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 10.3 hours before the alert went out and 183 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: 594 J/kg
Mixed-layer CIN: -104 J/kg
Mixed-layer LCL: 766 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 62 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.8

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 18, 2:21 PM CDT	Mesoscale Discussion	SPC	Autauga, Barbour, Bibb, Blount, Bullock, Calhoun and 34 more	84 min
Aug 18, 2:40 PM CDT	Severe Thunderstorm Watch	SPC	Autauga, Barbour, Bibb, Blount, Bullock, Calhoun and 33 more	7 hr
Aug 18, 6:10 PM CDT	Severe Thunderstorm Watch	SPC	Butler, Clarke, Coffee, Conecuh, Covington, Crenshaw and 7 more	9 hr
Aug 17, 7:21 PM CDT	Mesoscale Discussion	SPC	Butts, Coweta, Fayette, Henry, Jasper, Spalding	54 min
Aug 18, 2:28 PM CDT	Severe Thunderstorm Watch	SPC	Columbia, Elbert, Lincoln, McDuffie, Richmond	7 hr

Nearby

Mesoscale Discussions in Alabama, 2024 Mesoscale Discussions in Georgia, 2024 Every mesoscale discussion in 2024

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.