Alert archive / Georgia / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 503

June 18, 201157 counties in Georgia; 20 counties in South Carolina

The Storm Prediction Center issued this severe thunderstorm watch at Jun 18, 2011, 4:08 PM EDT for 57 counties in Georgia; 20 counties in South Carolina. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jun 18, 2011, 4:08 PM EDT (20:08 UTC)
Expired
Jun 18, 2011, 10:30 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
70 kt
All 77 counties

Baldwin County, GA, Barrow County, GA, Burke County, GA, Butts County, GA, Carroll County, GA, Clarke County, GA, Clayton County, GA, Cobb County, GA, Columbia County, GA, Coweta County, GA, DeKalb County, GA, Douglas County, GA, Elbert County, GA, Emanuel County, GA, Fayette County, GA, Fulton County, GA, Glascock County, GA, Greene County, GA, Gwinnett County, GA, Hancock County, GA, Haralson County, GA, Harris County, GA, Heard County, GA, Henry County, GA, Jackson County, GA, Jasper County, GA, Jefferson County, GA, Johnson County, GA, Jones County, GA, Lamar County, GA, Laurens County, GA, Lincoln County, GA, Madison County, GA, McDuffie County, GA, Meriwether County, GA, Monroe County, GA, Morgan County, GA, Newton County, GA, Oconee County, GA, Oglethorpe County, GA, Paulding County, GA, Pike County, GA, Polk County, GA, Putnam County, GA, Richmond County, GA, Rockdale County, GA, Spalding County, GA, Talbot County, GA, Taliaferro County, GA, Treutlen County, GA, Troup County, GA, Upson County, GA, Walton County, GA, Warren County, GA, Washington County, GA, Wilkes County, GA, Wilkinson County, GA, Abbeville County, SC, Aiken County, SC, Bamberg County, SC, Barnwell County, SC, Calhoun County, SC, Chesterfield County, SC, Clarendon County, SC, Edgefield County, SC, Fairfield County, SC, Greenwood County, SC, Kershaw County, SC, Lancaster County, SC, Lee County, SC, Lexington County, SC, McCormick County, SC, Newberry County, SC, Orangeburg County, SC, Richland County, SC, Saluda County, SC, Sumter County, SC

The radar

The Robins AFB radar (KJGX), 128 km from the middle of the area, began a volume at 20:11 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
10%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
80%
One or more gusts of 65 knots or more
50%
Ten or more severe hail reports
70%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

23 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jun 18, 4:23 PM EDTSevere Thunderstorm WarningCAEChesterfield, Fairfield, Kershaw, Lancaster, Lee67 min
Jun 18, 4:34 PM EDTSevere Thunderstorm WarningGSPAbbeville, Greenwood, Laurens71 min
Jun 18, 5:01 PM EDTSevere Thunderstorm WarningCAEFairfield, Kershaw, Lexington, Newberry, Richland, Saluda59 min
Jun 18, 5:26 PM EDTSevere Thunderstorm WarningCAEChesterfield, Fairfield, Kershaw, Lancaster, Lee34 min
Jun 18, 5:28 PM EDTSevere Thunderstorm WarningFFCGreene, Morgan, Oconee, Walton29 min
Jun 18, 5:31 PM EDTSevere Thunderstorm WarningFFCCobb, Haralson, Paulding44 min
Jun 18, 5:41 PM EDTSevere Thunderstorm WarningGSPAbbeville, Greenwood, Laurens64 min
Jun 18, 5:50 PM EDTSevere Thunderstorm WarningFFCGwinnett, Newton, Rockdale, Walton25 min
Jun 18, 5:53 PM EDTSevere Thunderstorm WarningFFCCobb, DeKalb, Fulton41 min
Jun 18, 5:58 PM EDTSevere Thunderstorm WarningCAEChesterfield32 min
Jun 18, 5:59 PM EDTSevere Thunderstorm WarningFFCBarrow, Forsyth, Gwinnett, Hall, Jackson46 min
Jun 18, 5:59 PM EDTSevere Thunderstorm WarningCAEAiken, Calhoun, Clarendon, Edgefield, Fairfield, Kershaw and 6 more61 min
Jun 18, 6:20 PM EDTSevere Thunderstorm WarningFFCMorgan, Walton40 min
Jun 18, 6:29 PM EDTSevere Thunderstorm WarningFFCDouglas, Fulton46 min
Jun 18, 6:37 PM EDTSevere Thunderstorm WarningFFCGreene, Morgan, Oconee, Oglethorpe38 min
Jun 18, 6:39 PM EDTSevere Thunderstorm WarningFFCClayton, DeKalb, Fulton, Henry51 min
Jun 18, 6:45 PM EDTSevere Thunderstorm WarningFFCClarke, Oglethorpe30 min
Jun 18, 6:48 PM EDTSevere Thunderstorm WarningGSPElbert59 min
Jun 18, 6:54 PM EDTSevere Thunderstorm WarningCAEEdgefield, McCormick36 min
Jun 18, 7:08 PM EDTSevere Thunderstorm WarningFFCCoweta, Fayette, Fulton15 min
Jun 18, 7:11 PM EDTSevere Thunderstorm WarningCAELincoln49 min
Jun 18, 8:28 PM EDTSevere Thunderstorm WarningCAEBurke, Richmond62 min
Jun 18, 9:09 PM EDTSevere Thunderstorm WarningCAEBamberg, Barnwell51 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 8.1 hours before the alert went out and 125 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-pSkew-T log-p diagram, Peachtre/Fal Fld, GA at 12:00Z on 2011-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1149 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peachtre/Fal Fld, GA at 12:00Z on 2011-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
1149 J/kg
Mixed-layer CIN
-132 J/kg
Mixed-layer LCL
704 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 18, 9:38 AM EDTMesoscale DiscussionSPCBanks, Bartow, Catoosa, Chattooga, Cherokee, Cobb and 22 more97 min
Jun 18, 11:05 AM EDTSevere Thunderstorm WatchSPCBanks, Bartow, Catoosa, Chattooga, Cherokee, Dade and 20 more9 hr
Jun 18, 2:21 PM EDTMesoscale DiscussionSPCBanks, Bartow, Catoosa, Chattooga, Cherokee, Dawson and 20 more84 min
Jun 18, 3:55 PM EDTMesoscale DiscussionSPCBarrow, Carroll, Clarke, Clayton, Cobb, Columbia and 25 more35 min
Jun 18, 6:49 PM EDTMesoscale DiscussionSPCBaldwin, Barrow, Bibb, Bleckley, Bulloch, Burke and 55 more86 min
Jun 18, 7:20 PM EDTSevere Thunderstorm WatchSPCBryan, Bulloch, Candler, Chatham, Effingham, Evans and 6 more5 hr
Jun 18, 5:46 PM EDTMesoscale DiscussionSPCChesterfield, Darlington, Dillon, Fairfield, Greenwood, Kershaw and 8 more59 min

Nearby

Severe Thunderstorm Watches in Georgia, 2011Severe Thunderstorm Watches in South Carolina, 2011Every severe thunderstorm watch in 2011

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.