Alert archive / Georgia / Tornado Watches in 2013

Tornado Watch 35

February 13, 201315 counties in Georgia

The Storm Prediction Center issued this tornado watch at Feb 13, 2013, 5:31 AM EST for 15 counties in Georgia. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Feb 13, 2013, 5:31 AM EST (10:31 UTC)
Expired
Feb 13, 2013, 9:00 AM EST
In force
3 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
60 kt

Counties Appling County, GA, Atkinson County, GA, Bacon County, GA, Brantley County, GA, Bryan County, GA, Chatham County, GA, Coffee County, GA, Glynn County, GA, Jeff Davis County, GA, Liberty County, GA, Long County, GA, McIntosh County, GA, Pierce County, GA, Ware County, GA, Wayne County, GA

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
30%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
20%
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
40%

Warnings issued inside it

1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Feb 13, 5:39 AM ESTSevere Thunderstorm WarningJAXAppling, Atkinson, Bacon, Brantley, Coffee, Pierce and 2 more51 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

Jacksonville, FL (KJAX), launched 00:00Z, 10.5 hours before the alert went out and 106 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, Jacksonville, FL at 00:00Z on 2013-02-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 218 joules per kilogram.LCLLFCEL10008507005003002001001 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, Jacksonville, FL at 00:00Z on 2013-02-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 186 square meters per square second.1939587897117136Sfc1 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
218 J/kg
Mixed-layer CIN
-93 J/kg
Mixed-layer LCL
887 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
186 m²/s²
0-3 km storm-relative helicity
359 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

The text

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

949 
WWUS20 KWNS 131036
SEL5  
SPC WW 131036
GAZ000-CWZ000-131400-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 35
NWS STORM PREDICTION CENTER NORMAN OK
530 AM EST WED FEB 13 2013

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

       SOUTHEAST GEORGIA
       COASTAL WATERS

EFFECTIVE THIS WEDNESDAY MORNING FROM 530 AM UNTIL 900 AM EST.

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 20 MILES SOUTH SOUTHEAST OF
WAYCROSS GEORGIA TO 55 MILES NORTH OF BRUNSWICK GEORGIA.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU5).

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...SCTD SUSTAINED TSTMS EXPECTED TO PERSIST IN ENVIRONMENT
OF DEEP...STRONG...LARGELY UNIDIRECTIONAL WSW FLOW OVER SE GA.
UPLIFT IS BEING FOCUSED ALONG SFC STNRY FRONT ALIGNED PARALLEL TO
DEEP FLOW. GIVEN STRENGTH OF DEEP SHEAR /60 KTS/...RICH MOISTURE /PW
AOA 1.5 INCHES/...AND FRICTIONALLY-ENHANCED LOW-LVL SHEAR CLOSER TO
THE ATLANTIC COAST...THE STORMS MOVING ALONG THE BOUNDARY COULD POSE
A TORNADO THREAT...IN ADDITION TO LOCALLY DMGG WIND...BEFORE MOVING
OFFSHORE.

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
400. MEAN STORM MOTION VECTOR 26040.


...CORFIDI

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 12, 11:46 PM ESTMesoscale DiscussionSPCAppling, Atkinson, Bacon, Ben Hill, Berrien, Brantley and 12 more119 min
Feb 13, 4:14 AM ESTMesoscale DiscussionSPCAppling, Atkinson, Bacon, Baker, Berrien, Brantley and 23 more2 hr
Feb 13, 8:38 AM ESTMesoscale DiscussionSPCBacon, Brantley, Camden, Charlton, Clinch, Echols and 4 more67 min

Nearby

Tornado Watches in Georgia, 2013Every tornado watch in 2013

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.