Tornado Watch 99

Issued

Apr 11, 2013, 3:45 PM CDT (20:45 UTC)

Expired

Apr 11, 2013, 10:00 PM CDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

1 in

Strongest gust expected

60 kt

The Atlanta radar (KFFC), 110 km from the middle of the area, began a volume at 20:46 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.

Two or more tornadoes

40%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

10%

One or more hailstones of 2 inches or more

5%

Six or more combined severe hail and wind reports

80%

• Mesoscale Discussion 445Apr 11, 2:21 PM CDT
• Mesoscale Discussion 447Apr 11, 3:26 PM CDT
• Mesoscale Discussion 451Apr 11, 5:54 PM CDT
• Mesoscale Discussion 454Apr 11, 9:52 PM CDT

427 
WWUS20 KWNS 112046
SEL9  
SPC WW 112046
ALZ000-GAZ000-120300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 99
NWS STORM PREDICTION CENTER NORMAN OK
445 PM EDT THU APR 11 2013

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

       EASTERN ALABAMA
       WEST CENTRAL AND NORTHWEST GEORGIA

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 445 PM UNTIL
1100 PM EDT.

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 APPROXIMATELY ALONG AND 70 STATUTE
MILES EAST AND WEST OF A LINE FROM 45 MILES NORTH NORTHEAST OF
ROME GEORGIA TO 20 MILES SOUTHEAST OF MONTGOMERY ALABAMA.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU9).

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 96...WW 97...WW 98...

DISCUSSION...PRE-FRONTAL CONVECTION CONTINUES TO DEVELOP ACROSS E
CENTRAL AL IN AN ENVIRONMENT OF MODERATE INSTABILITY AND SLOWLY
INCREASING VERTICAL SHEAR.  SOME OF THESE STORMS COULD CONTINUE TO
DEVELOP SUPERCELL STRUCTURES FOR THE NEXT FEW HOURS...AND THE
STRONGEST STORMS MAY POSE A RISK FOR A TORNADO OR TWO. 
OTHERWISE...THE FRONTAL SQUALL LINE IN AL WILL PROGRESS EWD INTO GA
LATE THIS EVENING THROUGH EARLY TONIGHT...WITH A CONTINUING RISK FOR
DAMAGING GUSTS AND PERHAPS A COUPLE OF EMBEDDED CIRCULATIONS WITH
QLCS TORNADOES.

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 24035.


...THOMPSON

Tornado Watches in Georgia, 2013Tornado Watches in Alabama, 2013Every tornado watch in 2013

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.