Alert archive / Georgia / Mesoscale Discussions in 2020

Mesoscale Discussion 378

April 13, 20204 counties in Florida; 21 counties in Georgia; 14 counties in South Carolina

The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2020, 6:17 AM EDT for 4 counties in Florida; 21 counties in Georgia; 14 counties in South Carolina. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued: Apr 13, 2020, 6:17 AM EDT (10:17 UTC)
Expired: Apr 13, 2020, 7:45 AM EDT
In force: 88 min
Issued by: the Storm Prediction Center

All 39 counties

Hamilton County, FL, Jefferson County, FL, Leon County, FL, Madison County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Brantley County, GA, Brooks County, GA, Bryan County, GA, Camden County, GA, Charlton County, GA, Chatham County, GA, Clinch County, GA, Echols County, GA, Effingham County, GA, Glynn County, GA, Lanier County, GA, Liberty County, GA, Long County, GA, Lowndes County, GA, McIntosh County, GA, Pierce County, GA, Ware County, GA, Wayne County, GA, Beaufort County, SC, Berkeley County, SC, Charleston County, SC, Clarendon County, SC, Colleton County, SC, Darlington County, SC, Dorchester County, SC, Florence County, SC, Georgetown County, SC, Horry County, SC, Jasper County, SC, Marion County, SC, Sumter County, SC, Williamsburg County, SC

The radar

The Charleston,SC radar (KCLX), 115 km from the middle of the area, began a volume at 10:17 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

Jacksonville, FL (KJAX), launched 00:00Z, 10.3 hours before the alert went out and 165 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: 1677 J/kg
Mixed-layer CIN: -59 J/kg
Mixed-layer LCL: 861 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 194 m²/s²
0-3 km storm-relative helicity: 292 m²/s²
Significant tornado parameter: 1.9
Supercell composite: 10.2

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
Apr 12, 11:28 PM EDT	Mesoscale Discussion	SPC	Escambia, Holmes, Okaloosa, Santa Rosa, Walton	92 min
Apr 12, 11:45 PM EDT	Tornado Watch	SPC	Bay, Calhoun, Escambia, Gulf, Holmes, Jackson and 4 more	8 hr
Apr 13, 3:20 AM EDT	Tornado Watch	SPC	Baker, Columbia, Duval, Franklin, Gadsden, Hamilton and 9 more	8 hr
Apr 13, 4:06 PM EDT	Mesoscale Discussion	SPC	Alachua, Bradford, Clay, Levy, Marion, Putnam and 1 more	84 min
Apr 12, 8:41 PM EDT	Mesoscale Discussion	SPC	Bartow, Catoosa, Cherokee, Dawson, Fannin, Floyd and 13 more	64 min
Apr 12, 8:57 PM EDT	Tornado Watch	SPC	Rabun	6 hr
Apr 12, 11:17 PM EDT	Mesoscale Discussion	SPC	Banks, Barrow, Bartow, Catoosa, Chattooga, Cherokee and 36 more	88 min
Apr 13, 1:51 AM EDT	Tornado Watch	SPC	Elbert, Franklin, Habersham, Hart, Rabun, Stephens	6 hr
Apr 13, 2:39 AM EDT	Mesoscale Discussion	SPC	Baker, Baldwin, Ben Hill, Bleckley, Burke, Calhoun and 37 more	96 min
Apr 13, 4:40 AM EDT	Mesoscale Discussion	SPC	Dillon, Horry, Marion, Marlboro	95 min
Apr 13, 5:01 AM EDT	Tornado Watch	SPC	Darlington, Dillon, Florence, Georgetown, Horry, Marion and 2 more	7 hr

Nearby

Mesoscale Discussions in Georgia, 2020 Mesoscale Discussions in South Carolina, 2020 Mesoscale Discussions in Florida, 2020 Every mesoscale discussion in 2020

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.