Alert archive / Florida / Tornado Watches in 2003

Tornado Watch 942

October 28, 200318 counties in Florida; Camden County, Georgia

The Storm Prediction Center issued this tornado watch at Oct 28, 2003, 4:30 PM EST for 18 counties in Florida; Camden County, Georgia. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: Oct 28, 2003, 4:30 PM EST (21:30 UTC)
Expired: Oct 28, 2003, 10:00 PM EST
In force: 6 hr
Issued by: the Storm Prediction Center

Counties Alachua County, FL, Baker County, FL, Bradford County, FL, Citrus County, FL, Clay County, FL, Dixie County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Hernando County, FL, Levy County, FL, Marion County, FL, Nassau County, FL, Pasco County, FL, Putnam County, FL, Saint Johns County, FL, Sumter County, FL, Union County, FL, Camden County, GA

The radar

The Jacksonville radar (KJAX), 117 km from the middle of the area, began a volume at 21:30 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.

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, 9.5 hours before the alert went out and 119 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 696 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 138 m²/s²
0-3 km storm-relative helicity: 188 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 282131
SEL2  
SPC WW 282130
FLZ000-GAZ000-CWZ000-290300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 942 
NWS STORM PREDICTION CENTER NORMAN OK 
430 PM EST TUE OCT 28 2003

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

       NORTHERN FLORIDA
       SOUTHEAST GEORGIA
       COASTAL WATERS

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 430 PM UNTIL
1000 PM EST.

TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 55 STATUTE MILES EITHER SIDE
OF A LINE FROM 60 MILES SOUTH OF CROSS CITY FLORIDA TO 50 MILES
EAST OF JACKSONVILLE 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 941. WATCH NUMBER 941 WILL NOT BE IN EFFECT AFTER 430
PM EST. 


DISCUSSION...SURFACE LOW MOVING ONSHORE NERN FL FROM  NERN GULF WITH
FRONTAL BOUNDARY EXTENDING ENEWD INTO ATLANTIC.  APPROACH OF S/WV
TROUGH CONTINUES TO ENHANCE DEEP LAYER SHEAR PROFILES NRN FL IN WARM
SECTOR.  WITH  LOW MOVING ACROSS NERN FL AND COLD FRONT MOVING
ONSHORE WRN COAST...THREAT OF ISOLATED TORNADIC SUPERCELLS WILL
PERSIST THRU THE EVENING.  IN ADDITION DOWNBURST WINDS ARE LIKELY
ASSOCIATED WITH THE LINE OF THUNDERSTORMS MOVING ONSHORE NEXT
SEVERAL HOURS.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 24030.


...HALES

292,0833 310,0812 295,0801 280,0823

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 28, 10:52 AM EST	Mesoscale Discussion	SPC	Alachua, Baker, Bradford, Clay, Columbia, Dixie and 14 more	53 min
Oct 28, 11:20 AM EST	Tornado Watch	SPC	Alachua, Baker, Bradford, Citrus, Clay, Columbia and 13 more	6 hr
Oct 28, 12:24 PM EST	Mesoscale Discussion	SPC	Alachua, Baker, Bradford, Citrus, Clay, Columbia and 13 more	66 min
Oct 28, 3:05 PM EST	Mesoscale Discussion	SPC	Alachua, Baker, Bradford, Citrus, Clay, Columbia and 13 more	55 min
Oct 28, 3:55 PM EST	Mesoscale Discussion	SPC	Baker, Columbia, Dixie, Gilchrist, Lafayette, Nassau and 2 more	65 min
Oct 28, 6:24 PM EST	Mesoscale Discussion	SPC	Alachua, Baker, Bradford, Citrus, Clay, Duval and 11 more	2 hr

Nearby

Tornado Watches in Florida, 2003 Tornado Watches in Georgia, 2003 Every tornado watch in 2003

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.