Alert archive / Florida / Tornado Watches in 2004

Tornado Watch 806

September 6, 200444 counties in Florida

The Storm Prediction Center issued this tornado watch at Sep 6, 2004, 1:20 PM EDT for 44 counties in Florida. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Sep 6, 2004, 1:20 PM EDT (17:20 UTC)
Expired
Sep 6, 2004, 8:00 PM EDT
In force
7 hr
Issued by
the Storm Prediction Center
All 44 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, Gadsden County, FL, Gilchrist County, FL, Hamilton County, FL, Hardee County, FL, Hernando County, FL, Highlands County, FL, Hillsborough County, FL, Indian River County, FL, Jefferson County, FL, Lafayette County, FL, Lake County, FL, Leon County, FL, Levy County, FL, Madison County, FL, Manatee County, FL, Marion County, FL, Nassau County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Pinellas County, FL, Polk County, FL, Putnam County, FL, Saint Johns County, FL, Saint Lucie County, FL, Sarasota County, FL, Seminole County, FL, Sumter County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL, Volusia County, FL, Wakulla County, FL

The radar

The Jacksonville radar (KJAX), 139 km from the middle of the area, began a volume at 17:22 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

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

IssuedProductOfficeCountiesLasted
Sep 6, 1:45 PM EDTTornado WarningTBWPolk30 min
Sep 6, 6:39 PM EDTTornado WarningJAXClay, Saint Johns51 min
Sep 6, 6:51 PM EDTTornado WarningJAXPutnam39 min
Sep 6, 7:13 PM EDTTornado WarningJAXClay, Saint Johns47 min
Sep 6, 7:33 PM EDTTornado WarningJAXClay27 min
Sep 6, 7:40 PM EDTTornado WarningJAXDuval, Saint Johns50 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, 5.3 hours before the alert went out and 141 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 2004-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 830 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 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 2004-09-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 235 square meters per square second.19395878Sfc1 km3 km6 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
830 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
653 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
235 m²/s²
0-3 km storm-relative helicity
235 m²/s²
Significant tornado parameter
1.1
Supercell composite
4.8

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 061719
SEL6  
SPC WW 061720
FLZ000-CWZ000-070000-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 806
NWS STORM PREDICTION CENTER NORMAN OK
120 PM EDT MON SEP 6 2004

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

       CENTRAL AND NORTH FLORIDA
       COASTAL WATERS

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 120 PM UNTIL 800
PM EDT.

TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 60 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 95 STATUTE MILES EAST AND WEST
OF A LINE FROM 70 MILES NORTH OF CROSS CITY FLORIDA TO 30 MILES
SOUTH 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 804. WATCH NUMBER 804 WILL NOT BE IN EFFECT AFTER 120
PM EDT. CONTINUE...WW 805...

DISCUSSION...THE OUTER ERN RAIN BANDS ASSOCIATED WITH TROPICAL STORM
FRANCES WILL CONTINUE TO ROTATE NWD ACROSS CENTRAL/N FL THROUGH THE
AFTERNOON.  DAYTIME HEATING BETWEEN THE BANDS WILL ENHANCE
INSTABILITY...WHILE VERTICAL SHEAR REMAINS SUFFICIENT FOR SUPERCELLS
CAPABLE OF PRODUCING TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 50 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550.
MEAN STORM MOTION VECTOR 18030.


...THOMPSON

303,0813 271,0794 271,0825 303,0844

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 5, 8:35 PM EDTTornado WatchSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 21 more9 hr
Sep 6, 12:12 AM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 21 more2 hr
Sep 6, 4:06 AM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 21 more84 min
Sep 6, 4:50 AM EDTTornado WatchSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 11 more9 hr
Sep 6, 7:48 AM EDTMesoscale DiscussionSPCBrevard, Charlotte, DeSoto, Hardee, Highlands, Lake and 8 more87 min
Sep 6, 7:55 AM EDTTornado WatchSPCBrevard, Charlotte, Citrus, DeSoto, Glades, Hardee and 21 more6 hr
Sep 6, 12:28 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Brevard, Charlotte, Citrus and 36 more92 min
Sep 6, 3:55 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Duval and 10 more2 hr
Sep 6, 7:12 PM EDTMesoscale DiscussionSPCBaker, Columbia, Duval, Nassau, Union2 hr
Sep 6, 7:45 PM EDTTornado WatchSPCBradford, Clay, Duval, Flagler, Nassau, Putnam and 1 more9 hr

Nearby

Tornado 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.