Alert archive / Florida / Tornado Watches in 2004

Tornado Watch 840

September 26, 200428 counties in Florida; 8 counties in Georgia

The Storm Prediction Center issued this tornado watch at Sep 26, 2004, 4:50 AM EDT for 28 counties in Florida; 8 counties in Georgia. It was in force for 12 hr.

The area

The outline as issued.

The facts

Issued
Sep 26, 2004, 4:50 AM EDT (08:50 UTC)
Expired
Sep 26, 2004, 5:00 PM EDT
In force
12 hr
Issued by
the Storm Prediction Center
All 36 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Brevard County, FL, Citrus County, FL, Clay County, FL, Columbia County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Hamilton County, FL, Hernando County, FL, Hillsborough County, FL, Indian River County, FL, Lake County, FL, Levy County, FL, Marion County, FL, Nassau County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Polk County, FL, Putnam County, FL, Saint Johns County, FL, Seminole County, FL, Sumter County, FL, Union County, FL, Volusia County, FL, Brantley County, GA, Camden County, GA, Charlton County, GA, Clinch County, GA, Echols County, GA, Glynn County, GA, Lanier County, GA, Ware County, GA

The radar

The Jacksonville radar (KJAX), 77 km from the middle of the area, began a volume at 08:52 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

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

IssuedProductOfficeCountiesLasted
Sep 26, 9:50 AM EDTFlash Flood WarningTBWPolk85 min
Sep 26, 11:43 AM EDTTornado WarningJAXFlagler47 min
Sep 26, 11:47 AM EDTFlash Flood WarningTBWHardee, Highlands, Hillsborough, Manatee, Pasco, Polk and 1 more8 hr
Sep 26, 12:01 PM EDTFlash Flood WarningMLBBrevard, Lake, Orange, Osceola, Seminole, Volusia6 hr
Sep 26, 2:34 PM EDTTornado WarningJAXSaint Johns41 min
Sep 26, 3:40 PM EDTFlash Flood WarningTBWCitrus, Hernando, Levy, Sumter4 hr
Sep 26, 4:46 PM EDTTornado WarningJAXNassau14 min
Sep 26, 4:59 PM EDTTornado WarningJAXNassau16 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 00:00Z, 8.8 hours before the alert went out and 79 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 00:00Z on 2004-09-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 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 00:00Z on 2004-09-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 212 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
6 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
570 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
212 m²/s²
0-3 km storm-relative helicity
302 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 260916
SEL0  
SPC WW 260850
FLZ000-GAZ000-CWZ000-262100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 840
NWS STORM PREDICTION CENTER NORMAN OK
450 AM EDT SUN SEP 26 2004

CORRECTED FOR HURRICANE NAME

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

       CENTRAL AND NORTH FLORIDA
       SOUTHEAST GEORGIA
       COASTAL WATERS

EFFECTIVE THIS SUNDAY MORNING AND AFTERNOON FROM 450 AM UNTIL 500
PM EDT.

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

THE TORNADO WATCH AREA IS ALONG AND 75 STATUTE MILES EAST AND WEST
OF A LINE FROM 25 MILES WEST NORTHWEST OF BRUNSWICK GEORGIA TO 5
MILES WEST OF AVON PARK 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...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 839. WATCH NUMBER 839 CORR 1
AM EDT.


DISCUSSION...HURRICANE JEANNE CONTINUES TO MOVE WNWWD ACROSS
CENTRAL FL...WITH A GRADUAL TURN MORE TO THE NW EXPECTED TODAY.  THE
TORNADO THREAT WILL INITIALLY BE SOMEWHAT LIMITED EARLY THIS MORNING
IN THE VICINITY OF THE STORM CORE.  HOWEVER...THE TORNADO THREAT IS
EXPECTED TO INCREASE SOME DURING THE MORNING FROM THE CAPE CANAVERAL
AREA NWD ALONG THE NE FL COAST AS MORE DISCRETE CONVECTIVE CELLS
WITHIN THE OUTER BANDS BEGIN TO MOVE ONSHORE.  THE THREAT FOR A
COUPLE OF TORNADOES SHOULD ALSO GRADUALLY SPREAD NWD AND INLAND TO
SE GA BY LATE MORNING OR EARLY AFTERNOON.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH EXTREME
TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI
WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 12040.


...THOMPSON

311,0803 273,0801 273,0823 311,0830

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 25, 8:48 PM EDTMesoscale DiscussionSPCBrevard, Flagler, Glades, Hendry, Highlands, Indian River and 10 more117 min
Sep 25, 11:10 PM EDTTornado WatchSPCBrevard, Flagler, Glades, Hardee, Hendry, Highlands and 14 more7 hr
Sep 26, 2:37 AM EDTMesoscale DiscussionSPCBrevard, Flagler, Highlands, Indian River, Lake, Marion and 6 more113 min
Sep 26, 8:21 AM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Brevard, Citrus, Clay and 18 more114 min
Sep 26, 11:13 AM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Brevard, Citrus, Clay and 22 more2 hr
Sep 26, 3:11 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Brevard, Citrus, Clay and 22 more2 hr
Sep 26, 4:25 PM EDTTornado WatchSPCAlachua, Baker, Bradford, Clay, Columbia, Duval and 8 more9 hr
Sep 26, 7:16 PM EDTMesoscale DiscussionSPCBaker, Duval, Nassau119 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.