Tornado Watch 684

Issued

Dec 17, 2012, 1:30 PM EST (18:30 UTC)

Expired

Dec 17, 2012, 6:45 PM EST

In force

5 hr

Issued by

the Storm Prediction Center

Largest hail expected

1 in

Strongest gust expected

65 kt

Two or more tornadoes

30%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

70%

One or more gusts of 65 knots or more

20%

Ten or more severe hail reports

5%

One or more hailstones of 2 inches or more

5%

Six or more combined severe hail and wind reports

95%

• Mesoscale Discussion 2169Dec 17, 11:49 AM EST
• Mesoscale Discussion 2173Dec 17, 2:28 PM EST

671 
WWUS20 KWNS 171837
SEL4
SPC WW 171837
FLZ000-GAZ000-CWZ000-180200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 684
NWS STORM PREDICTION CENTER NORMAN OK
130 PM EST MON DEC 17 2012

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

       NORTHERN FLORIDA
       SOUTHERN AND EASTERN GEORGIA
       COASTAL WATERS

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 130 PM UNTIL 900
PM EST.

TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 75 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 50 STATUTE
MILES EITHER SIDE OF A LINE FROM 10 MILES WEST NORTHWEST OF
APALACHICOLA FLORIDA TO 10 MILES EAST OF SAVANNAH GEORGIA.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU4).

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...CONTINUE...WW 683...

DISCUSSION...SW-NE SQLN IN SW GA/CNTRL FL PANHANDLE EXPECTED TO
CONTINUE GENERALLY E/ENE AT 40-50 KTS THROUGH EARLY EVE. ISOLD
ADDITIONAL STORMS MAY FORM LATER THIS AFTN IN WEAKLY CONFLUENT FLOW
AHEAD OF LINE. DEEP/STRONG...LARGELY UNIDIRECTIONAL WSW FLOW IS
PRESENT TO SUPPORT SUSTAINED STORMS/SUPERCELLS. THESE WILL HAVE THE
POTENTIAL TO PRODUCE TORNADOES...ESPECIALLY NEAR LEWP CRESTS AND/OR
NEAR WARM FRONT IN SE GA/SAVANNAH RVR VLY. CONVERGENCE
WILL...HOWEVER... REMAIN WEAK...AND BACK-VEER PATTERN AROUND 700 MB
IN AREA WIND PROFILES MAY SOMEWHAT LIMIT OVERALL TORNADO
THREAT...ESPECIALLY WITH SWD EXTENT IN WW. NEVERTHELESS...STRENGTH
OF WIND FIELD AND LIKELIHOOD FOR SMALL BOWING STRUCTURES SUGGEST
POTENTIAL FOR DMGG WIND SWD THROUGH THE CNTRL/ERN FL PANHANDLE/NRN
FL.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450.
MEAN STORM MOTION VECTOR 26045.


...CORFIDI

Tornado Watches in Georgia, 2012Tornado Watches in Florida, 2012Every tornado watch in 2012

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.