Alert archive / Florida / Tornado Watches in 2004

Tornado Watch 744

August 12, 200436 counties in Florida; 25 counties in Georgia

The Storm Prediction Center issued this tornado watch at Aug 12, 2004, 1:50 PM EDT for 36 counties in Florida; 25 counties in Georgia. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Aug 12, 2004, 1:50 PM EDT (17:50 UTC)
Expired
Aug 12, 2004, 9:00 PM EDT
In force
7 hr
Issued by
the Storm Prediction Center
All 61 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Brevard County, FL, Citrus County, FL, Clay County, FL, Columbia County, FL, Dixie County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Hamilton County, FL, Hardee County, FL, Hernando County, FL, Hillsborough County, FL, Indian River County, FL, Lafayette County, FL, Lake County, FL, Levy County, FL, Madison County, FL, Manatee County, FL, Marion County, FL, Nassau County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Pinellas County, FL, Polk County, FL, Putnam County, FL, Saint Johns County, FL, Seminole County, FL, Sumter County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL, Volusia County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Ben Hill County, GA, Berrien County, GA, Brantley County, GA, Brooks County, GA, Camden County, GA, Charlton County, GA, Clinch County, GA, Coffee County, GA, Cook County, GA, Echols County, GA, Glynn County, GA, Irwin County, GA, Jeff Davis County, GA, Lanier County, GA, Liberty County, GA, Long County, GA, Lowndes County, GA, McIntosh County, GA, Pierce County, GA, Tift County, GA, Ware County, GA, Wayne County, GA

The radar

The Jacksonville radar (KJAX), 152 km from the middle of the area, began a volume at 17:54 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

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

IssuedProductOfficeCountiesLasted
Aug 12, 2:26 PM EDTSevere Thunderstorm WarningMLBBrevard49 min
Aug 12, 2:33 PM EDTTornado WarningJAXBradford, Union27 min
Aug 12, 3:03 PM EDTTornado WarningJAXBaker, Clay, Duval27 min
Aug 12, 3:13 PM EDTSevere Thunderstorm WarningJAXPutnam47 min
Aug 12, 3:57 PM EDTSevere Thunderstorm WarningJAXSaint Johns33 min
Aug 12, 4:01 PM EDTTornado WarningJAXDuval44 min
Aug 12, 4:24 PM EDTTornado WarningJAXNassau21 min
Aug 12, 5:55 PM EDTTornado WarningJAXFlagler35 min
Aug 12, 6:09 PM EDTTornado WarningJAXWayne36 min
Aug 12, 6:21 PM EDTTornado WarningCHSLiberty, Long24 min
Aug 12, 6:42 PM EDTTornado WarningCHSLiberty, Long, McIntosh33 min
Aug 12, 7:16 PM EDTTornado WarningCHSLiberty, McIntosh29 min
Aug 12, 7:29 PM EDTFlash Flood WarningCHSCandler, Liberty, Tattnall26 days
Aug 12, 7:35 PM EDTSevere Thunderstorm WarningCHSBryan, Chatham, Liberty25 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

Jacksonville, FL (KJAX), launched 12:00Z, 5.8 hours before the alert went out and 154 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, Jacksonville, FL at 12:00Z on 2004-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 877 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, Jacksonville, FL at 12:00Z on 2004-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 75 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
877 J/kg
Mixed-layer CIN
-57 J/kg
Mixed-layer LCL
900 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.0

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 121752
SEL4  
SPC WW 121750
FLZ000-GAZ000-CWZ000-130100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 744
NWS STORM PREDICTION CENTER NORMAN OK
ISSUED BY AFWA OFFUTT AIR FORCE BASE BELLEVUE NE
150 PM EDT THU AUG 12 2004

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

       CENTRAL AND NORTHERN FLORIDA
       SOUTHEAST GEORGIA
       COASTAL WATERS

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 150 PM UNTIL
900 PM EDT.

TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 120 STATUTE MILES EAST AND
WEST OF A LINE FROM 50 MILES NORTH OF BRUNSWICK GEORGIA TO 50
MILES SOUTHEAST OF SAINT PETERSBURG FLORIDA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION... WATCH NUMBER WILL NOT BE IN EFFECT
AFTER 150 PM EDT. CONTINUE...WW 743...

DISCUSSION...THREAT FOR ISOLD TORNADOES ARE EXPECTED TO PERSIST
THROUGH EARLY EVENING AS REMNANTS OF TROPICAL STORM BONNIE MOVES
ONSHORE.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 24035.


...AFWA

315,0792 272,0800 272,0840 315,0832

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, 8:50 AM EDTTornado WatchSPCAlachua, Baker, Bay, Bradford, Calhoun, Clay and 23 more5 hr
Aug 12, 12:50 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 19 more55 min
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 Florida, 2004Tornado Watches in Georgia, 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.