Alert archive / Georgia / Mesoscale Discussions in 2018

Mesoscale Discussion 879

June 25, 201824 counties in Georgia; Aiken County, Barnwell County, Edgefield County, South Carolina

The Storm Prediction Center issued this mesoscale discussion at Jun 25, 2018, 7:44 PM EDT for 24 counties in Georgia; Aiken County, Barnwell County, Edgefield County, South Carolina. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jun 25, 2018, 7:44 PM EDT (23:44 UTC)
Expired: Jun 25, 2018, 9:45 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 5%

All 27 counties

Ben Hill County, GA, Burke County, GA, Candler County, GA, Colquitt County, GA, Columbia County, GA, Cook County, GA, Dodge County, GA, Emanuel County, GA, Grady County, GA, Irwin County, GA, Jefferson County, GA, Jenkins County, GA, Johnson County, GA, Laurens County, GA, Montgomery County, GA, Richmond County, GA, Telfair County, GA, Thomas County, GA, Tift County, GA, Treutlen County, GA, Turner County, GA, Wheeler County, GA, Wilcox County, GA, Worth County, GA, Aiken County, SC, Barnwell County, SC, Edgefield County, SC

The radar

The Robins AFB radar (KJGX), 58 km from the middle of the area, began a volume at 23:43 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, 11.7 hours before the alert went out and 188 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: 1416 J/kg
Mixed-layer CIN: -53 J/kg
Mixed-layer LCL: 1094 m above ground
0-6 km bulk shear: 9 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: -7 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Jun 25, 12:29 PM EDT	Mesoscale Discussion	SPC	Habersham, Rabun, Stephens, Towns, Union, White	61 min
Jun 25, 1:02 PM EDT	Severe Thunderstorm Watch	SPC	Elbert, Franklin, Habersham, Hart, Rabun, Stephens	9 hr
Jun 25, 6:23 PM EDT	Mesoscale Discussion	SPC	Elbert, Franklin, Hart	2 hr

Nearby

Mesoscale Discussions in Georgia, 2018 Mesoscale Discussions in South Carolina, 2018 Every mesoscale discussion in 2018

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.