Tornado Watch 640

Issued

Sep 17, 2012, 6:39 PM EDT (22:39 UTC)

Expired

Sep 18, 2012, 3:00 AM EDT

In force

8 hr

Issued by

the Storm Prediction Center

Largest hail expected

0.5 in

Strongest gust expected

60 kt

The Atlanta radar (KFFC), 97 km from the middle of the area, began a volume at 22:42 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

30%

One or more gusts of 65 knots or more

5%

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

70%

• Mesoscale Discussion 1951Sep 17, 4:53 PM EDT
• Mesoscale Discussion 1952Sep 17, 6:14 PM EDT
• Mesoscale Discussion 1953Sep 17, 8:14 PM EDT
• Mesoscale Discussion 1954Sep 17, 10:21 PM EDT
• Mesoscale Discussion 1955Sep 18, 12:23 AM EDT

488 
WWUS20 KWNS 172241
SEL0
SPC WW 172241
GAZ000-NCZ000-SCZ000-TNZ000-180700-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 640
NWS STORM PREDICTION CENTER NORMAN OK
640 PM EDT MON SEP 17 2012

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

       NORTHERN AND CENTRAL GEORGIA
       WESTERN NORTH CAROLINA
       UPSTATE SOUTH CAROLINA
       EASTERN TENNESSEE

EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 640 PM UNTIL
300 AM 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 APPROXIMATELY ALONG AND 65 STATUTE
MILES EAST AND WEST OF A LINE FROM 120 MILES NORTH NORTHWEST OF
ATHENS GEORGIA TO 40 MILES SOUTH SOUTHWEST OF MACON GEORGIA.  FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU0).

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...SEVERAL SHORT BANDS/SMALL CLUSTERS OF TSTMS EXPECTED TO
PERSIST AND POSSIBLY INCREASE IN COVERAGE THROUGH LATE TNGT OVER
PARTS OF THE SRN APPALACHIANS...PIEDMONT...AND CUMBERLAND PLATEAU AS
MOIST/CONFLUENT FLOW STRENGTHENS DOWNSTREAM FROM SRN STREAM IMPULSE
ACCELERATING NEWD FROM LA. WHILE UPDRAFT INTENSITY WILL BE LIMITED
BY WEAK LOW TO MID-LVL LAPSE RATES...POTENTIAL WILL EXIST FOR
LOW-LVL MESOCYCLONES/POSSIBLE TORNADOES...MAINLY ALONG/NEAR
SLOWLY-ADVANCING WARM FRONT NOW DRAPED ALONG THE SRN FRINGES OF THE
MOUNTAINS.

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
450. MEAN STORM MOTION VECTOR 21030.


...CORFIDI

Tornado Watches in Georgia, 2012Tornado Watches in Tennessee, 2012Tornado Watches in North Carolina, 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; radar from the NEXRAD Level II archive.