Alert archive / Georgia / Severe Thunderstorm Watches in 2004

Severe Thunderstorm Watch 917

December 9, 2004Jackson County, Florida; 33 counties in Georgia

The Storm Prediction Center issued this severe thunderstorm watch at Dec 9, 2004, 11:45 AM CST for Jackson County, Florida; 33 counties in Georgia. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Dec 9, 2004, 11:45 AM CST (17:45 UTC)
Expired
Dec 9, 2004, 5:00 PM CST
In force
5 hr
Issued by
the Storm Prediction Center
All 34 counties

Jackson County, FL, Baker County, GA, Bleckley County, GA, Brooks County, GA, Calhoun County, GA, Colquitt County, GA, Cook County, GA, Crisp County, GA, Decatur County, GA, Dodge County, GA, Dooly County, GA, Dougherty County, GA, Early County, GA, Grady County, GA, Houston County, GA, Irwin County, GA, Laurens County, GA, Lee County, GA, Macon County, GA, Marion County, GA, Miller County, GA, Mitchell County, GA, Pulaski County, GA, Randolph County, GA, Schley County, GA, Seminole County, GA, Sumter County, GA, Terrell County, GA, Thomas County, GA, Tift County, GA, Turner County, GA, Webster County, GA, Wilcox County, GA, Worth County, GA

The radar

The Tallahassee radar (KTLH), 105 km from the middle of the area, began a volume at 17:48 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.

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, 5.8 hours before the alert went out and 226 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 2004-12-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 12 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 2004-12-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 237 square meters per square second.1939587897Sfc1 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
12 J/kg
Mixed-layer CIN
-160 J/kg
Mixed-layer LCL
512 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
237 m²/s²
0-3 km storm-relative helicity
307 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 9, 4:22 AM CSTMesoscale DiscussionSPCEscambia, Santa Rosa83 min
Dec 9, 10:24 AM CSTMesoscale DiscussionSPCBay, Calhoun, Gadsden, Holmes, Jackson, Liberty and 1 more2 hr

Nearby

Severe Thunderstorm Watches in Georgia, 2004Severe Thunderstorm Watches in Florida, 2004Every severe thunderstorm watch in 2004

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.