Alert archive / Florida / Tornado Watches in 2004

Tornado Watch 838

September 25, 200418 counties in Florida

The Storm Prediction Center issued this tornado watch at Sep 25, 2004, 4:25 PM EDT for 18 counties in Florida. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Sep 25, 2004, 4:25 PM EDT (20:25 UTC)
Expired
Sep 26, 2004, 12:00 AM EDT
In force
8 hr
Issued by
the Storm Prediction Center

Counties Brevard County, FL, Flagler County, FL, Glades County, FL, Hendry County, FL, Highlands County, FL, Indian River County, FL, Lake County, FL, Marion County, FL, Martin County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Palm Beach County, FL, Polk County, FL, Putnam County, FL, Saint Lucie County, FL, Seminole County, FL, Volusia County, FL

The radar

The Melbourne radar (KMLB), 40 km from the middle of the area, began a volume at 20:25 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 25, 5:51 PM EDTTornado WarningMLBIndian River, Okeechobee29 min
Sep 25, 6:30 PM EDTTornado WarningMLBMartin, Okeechobee, Saint Lucie30 min
Sep 25, 6:46 PM EDTTornado WarningMLBBrevard, Orange29 min
Sep 25, 8:53 PM EDTFlash Flood WarningMLBIndian River, Martin, Saint Lucie4 hr
Sep 25, 9:06 PM EDTTornado WarningMLBMartin, Saint Lucie54 min
Sep 25, 9:47 PM EDTTornado WarningMLBIndian River58 min
Sep 25, 10:30 PM EDTFlash Flood WarningMFLPalm Beach4 hr
Sep 25, 11:58 PM EDTTornado WarningMLBBrevard62 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

Tampa Bay, FL (KTBW), launched 12:00Z, 8.4 hours before the alert went out and 169 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, Tampa Bay, FL at 12:00Z on 2004-09-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Tampa Bay, FL at 12:00Z on 2004-09-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 square meters per square second.1939Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
623 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
105 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 252023
SEL8  
SPC WW 252025
FLZ000-CWZ000-260400-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 838
NWS STORM PREDICTION CENTER NORMAN OK
425 PM EDT SAT SEP 25 2004

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

       EASTERN FLORIDA PENINSULA
       COASTAL WATERS

EFFECTIVE THIS SATURDAY AFTERNOON FROM 425 PM UNTIL MIDNIGHT 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 50 STATUTE MILES EAST AND WEST
OF A LINE FROM 50 MILES NORTH NORTHWEST OF DAYTONA BEACH FLORIDA
TO 40 MILES SOUTHWEST OF WEST PALM BEACH 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.

DISCUSSION...HURRICANE JEANNE IS EXPECTED TO MAKE LANDFALL LATER
THIS EVENING NEAR VRB. MLB VAD SHOWS STRONG LOW LEVEL VERTICAL
SHEAR IS NOW IN PLACE AHEAD OF SYSTEM. CONVECTIVE BANDS IN WEST AND
NORTHWEST QUADRANTS WILL POSE A RISK OF TROPICAL TORNADOES.

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 550.
MEAN STORM MOTION VECTOR 07045.


...HART

295,0803 261,0794 261,0811 295,0821

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 25, 2:43 PM EDTMesoscale DiscussionSPCBrevard, Flagler, Indian River, Lake, Orange, Osceola and 3 more3 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.