Alert archive / Georgia / Tornado Watches in 2004

Tornado Watch 742

August 12, 200429 counties in Florida; 44 counties in Georgia

The Storm Prediction Center issued this tornado watch at Aug 12, 2004, 8:50 AM EDT for 29 counties in Florida; 44 counties in Georgia. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Aug 12, 2004, 8:50 AM EDT (12:50 UTC)
Expired
Aug 12, 2004, 2:00 PM EDT
In force
5 hr
Issued by
the Storm Prediction Center
All 73 counties

Alachua County, FL, Baker County, FL, Bay County, FL, Bradford County, FL, Calhoun County, FL, Clay County, FL, Columbia County, FL, Dixie County, FL, Duval County, FL, Franklin County, FL, Gadsden County, FL, Gilchrist County, FL, Gulf County, FL, Hamilton County, FL, Jackson County, FL, Jefferson County, FL, Lafayette County, FL, Leon County, FL, Levy County, FL, Liberty County, FL, Madison County, FL, Marion County, FL, Nassau County, FL, Putnam County, FL, Saint Johns County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL, Wakulla County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Baker County, GA, Ben Hill County, GA, Berrien County, GA, Brantley County, GA, Brooks County, GA, Calhoun County, GA, Camden County, GA, Charlton County, GA, Clay County, GA, Clinch County, GA, Coffee County, GA, Colquitt County, GA, Cook County, GA, Crisp County, GA, Decatur County, GA, Dougherty County, GA, Early County, GA, Echols County, GA, Glynn County, GA, Grady County, GA, Irwin County, GA, Jeff Davis County, GA, Lanier County, GA, Lee County, GA, Liberty County, GA, Long County, GA, Lowndes County, GA, McIntosh County, GA, Miller County, GA, Mitchell County, GA, Pierce County, GA, Randolph County, GA, Seminole County, GA, Telfair County, GA, Terrell County, GA, Thomas County, GA, Tift County, GA, Turner County, GA, Ware County, GA, Wayne County, GA, Worth County, GA

The radar

The Tallahassee radar (KTLH), 54 km from the middle of the area, began a volume at 12:51 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.

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Aug 12, 11:12 AM EDTFlash Flood WarningTAEJefferson, Lafayette, Taylor4 hr
Aug 12, 12:43 PM EDTFlash Flood WarningTAEDixie32 min
Aug 12, 1:09 PM EDTFlash Flood WarningTAEDixie3 hr

Discussions around it

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

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 0.8 hours before the alert went out and 52 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, Tallahassee Rgnl, FL at 12:00Z on 2004-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1178 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, Tallahassee Rgnl, FL at 12:00Z on 2004-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 33 square meters per square second.193958Sfc1 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
1178 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
630 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
33 m²/s²
0-3 km storm-relative helicity
50 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS20 KWNS 121251
SEL2  
SPC WW 121250
?Z000-FLZ000-GAZ000-CWZ000-121800-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 742
NWS STORM PREDICTION CENTER NORMAN OK
850 AM EDT THU AUG 12 2004

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 12, 8:00 AM EDTMesoscale DiscussionSPCAlachua, Baker, Bay, Bradford, Calhoun, Columbia and 18 more3 hr
Aug 12, 12:50 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 19 more55 min
Aug 12, 1:50 PM EDTTornado WatchSPCAlachua, Baker, Bradford, Brevard, Citrus, Clay and 30 more7 hr
Aug 12, 7:02 PM EDTMesoscale DiscussionSPCBrevard, Clay, Duval, Flagler, Hardee, Indian River and 9 more88 min
Aug 12, 4:09 AM EDTMesoscale DiscussionSPCBarrow, Bartow, Carroll, Cherokee, Clayton, Cobb and 14 more3 hr
Aug 12, 10:02 AM EDTMesoscale DiscussionSPCBleckley, Bulloch, Burke, Candler, Columbia, Effingham and 13 more88 min
Aug 12, 11:45 AM EDTTornado WatchSPCBleckley, Bryan, Bulloch, Burke, Candler, Chatham and 25 more6 hr
Aug 12, 4:06 PM EDTMesoscale DiscussionSPCBryan, Bulloch, Candler, Chatham, Effingham, Evans and 6 more84 min

Nearby

Tornado Watches in Georgia, 2004Tornado Watches in Florida, 2004Every tornado 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.