Alert archive / South Carolina / Severe Thunderstorm Watches in 2007
Severe Thunderstorm Watch 548
The Storm Prediction Center issued this severe thunderstorm watch at Jul 20, 2007, 3:02 PM EDT for 21 counties in Georgia; 25 counties in South Carolina. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2007, 3:02 PM EDT (19:02 UTC)
- Expired
- Jul 20, 2007, 10:00 PM EDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 46 counties
Brantley County, GA, Bryan County, GA, Bulloch County, GA, Burke County, GA, Candler County, GA, Chatham County, GA, Effingham County, GA, Emanuel County, GA, Evans County, GA, Glynn County, GA, Jefferson County, GA, Jenkins County, GA, Liberty County, GA, Long County, GA, McIntosh County, GA, Pierce County, GA, Richmond County, GA, Screven County, GA, Tattnall County, GA, Toombs County, GA, Wayne County, GA, Aiken County, SC, Allendale County, SC, Bamberg County, SC, Barnwell County, SC, Beaufort County, SC, Berkeley County, SC, Calhoun County, SC, Charleston County, SC, Clarendon County, SC, Colleton County, SC, Darlington County, SC, Dorchester County, SC, Florence County, SC, Georgetown County, SC, Hampton County, SC, Horry County, SC, Jasper County, SC, Kershaw County, SC, Lee County, SC, Lexington County, SC, Marion County, SC, Orangeburg County, SC, Richland County, SC, Sumter County, SC, Williamsburg County, SC
The radar
The Charleston,SC radar (KCLX), 34 km from the middle of the area, began a volume at 19:02 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
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
14 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 4:18 PM EDT | Severe Thunderstorm Warning | ILM | Williamsburg | 42 min |
| Jul 20, 4:58 PM EDT | Severe Thunderstorm Warning | FFC | Emanuel | 62 min |
| Jul 20, 5:21 PM EDT | Severe Thunderstorm Warning | FFC | Toombs | 39 min |
| Jul 20, 5:33 PM EDT | Severe Thunderstorm Warning | CHS | Candler, Tattnall | 57 min |
| Jul 20, 5:41 PM EDT | Severe Thunderstorm Warning | CHS | Jasper | 20 min |
| Jul 20, 6:08 PM EDT | Severe Thunderstorm Warning | CHS | Bulloch | 67 min |
| Jul 20, 6:11 PM EDT | Severe Thunderstorm Warning | CHS | Evans | 29 min |
| Jul 20, 6:19 PM EDT | Severe Thunderstorm Warning | JAX | Wayne | 42 min |
| Jul 20, 6:29 PM EDT | Severe Thunderstorm Warning | JAX | Bacon, Pierce | 61 min |
| Jul 20, 8:08 PM EDT | Severe Thunderstorm Warning | CHS | Berkeley | 52 min |
| Jul 20, 8:28 PM EDT | Tornado Warning | CHS | Berkeley | 32 min |
| Jul 20, 8:45 PM EDT | Severe Thunderstorm Warning | CHS | Berkeley, Charleston | 45 min |
| Jul 20, 8:59 PM EDT | Severe Thunderstorm Warning | CHS | Berkeley, Charleston | 46 min |
| Jul 20, 9:43 PM EDT | Severe Thunderstorm Warning | CHS | Charleston | 47 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
Charleston AFB, SC (KCHS), launched 12:00Z, 7.0 hours before the alert went out and 92 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.
- Mixed-layer CAPE
- 2309 J/kg
- Mixed-layer CIN
- -53 J/kg
- Mixed-layer LCL
- 867 m above ground
- 0-6 km bulk shear
- 9 kt
- 0-1 km storm-relative helicity
- 5 m²/s²
- 0-3 km storm-relative helicity
- -8 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 11:02 AM EDT | Mesoscale Discussion | SPC | Bartow, Carroll, Cherokee, Clayton, Cobb, Coweta and 9 more | 88 min |
| Jul 20, 11:21 AM EDT | Severe Thunderstorm Watch | SPC | Bartow, Carroll, Chattahoochee, Chattooga, Cobb, Coweta and 22 more | 8 hr |
| Jul 20, 1:11 PM EDT | Mesoscale Discussion | SPC | Baldwin, Ben Hill, Bibb, Bleckley, Butts, Crawford and 34 more | 94 min |
| Jul 20, 1:47 PM EDT | Severe Thunderstorm Watch | SPC | Appling, Atkinson, Bacon, Baker, Baldwin, Ben Hill and 46 more | 6 hr |
| Jul 20, 1:52 PM EDT | Mesoscale Discussion | SPC | Burke, Columbia, Glascock, Jefferson, Jenkins, Lincoln and 5 more | 83 min |
| Jul 20, 3:55 PM EDT | Mesoscale Discussion | SPC | Appling, Atkinson, Bacon, Baker, Baldwin, Ben Hill and 71 more | 2 hr |
| Jul 20, 7:34 PM EDT | Mesoscale Discussion | SPC | Brantley, Camden, Charlton, Chatham, Glynn, Liberty and 4 more | 56 min |
Nearby
Severe Thunderstorm Watches in South Carolina, 2007Severe Thunderstorm Watches in Georgia, 2007Every severe thunderstorm watch in 2007
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.