Alert archive / Georgia / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 334, NWS Atlanta, GA

August 10, 2012Dawson County, Forsyth County, Georgia

NWS Atlanta, GA issued this severe thunderstorm warning at Aug 10, 2012, 9:44 PM EDT for Dawson County, Forsyth County, Georgia. It was in force for 46 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 10, 2012, 9:44 PM EDT (01:44 UTC)
Expired: Aug 10, 2012, 10:30 PM EDT
In force: 46 min
Issued by: NWS Atlanta, GA
Area: Storm-based polygon

Counties Dawson County, GA, Forsyth County, GA

The radar

The Atlanta radar (KFFC), 119 km from the middle of the area, began a volume at 01:46 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.

What was reported inside it

Time	Report	Where	Remark
Aug 10, 10:00 PM EDT	TSTM WND DMG	7 Se Dawsonville, GA	A COUPLE OF TREES WERE BLOWN DOWN ALONG GEORGIA HIGHWAY 53 NEAR WAR HILL PARK ROAD.
Aug 10, 10:05 PM EDT	TSTM WND DMG	2 Ene Hollis Lathem Res, GA	DAWSON COUNTY 911 RELAYED A REPORT OF 2 DOWNED POWER LINES ON COWART ROAD. TIME ESTIMATED FROM RADAR.
Aug 10, 10:15 PM EDT	TSTM WND DMG	1 W Matt, GA	FORSYTH COUNTY 911 RELAYED REPORTS OF 2 DOWNED TREES IN THE NORTHERN PORTION OF THE COUNTY. TIME ESTIMATED FROM RADAR.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 1.7 hours before the alert went out and 115 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: 1442 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 974 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 26 m²/s²
0-3 km storm-relative helicity: 60 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

977 
WUUS52 KFFC 110144
SVRFFC
GAC085-117-110230-
/O.NEW.KFFC.SV.W.0334.120811T0144Z-120811T0230Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
944 PM EDT FRI AUG 10 2012

THE NATIONAL WEATHER SERVICE IN PEACHTREE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN DAWSON COUNTY IN NORTH CENTRAL GEORGIA
  NORTHERN FORSYTH COUNTY IN NORTH CENTRAL GEORGIA

* UNTIL 1030 PM EDT

* AT 942 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS UP TO 60
  MPH.  THIS STORM WAS LOCATED NEAR DAWSONVILLE...MOVING EAST AT 15
  MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  SILVER CITY...COAL MOUNTAIN...DOUGHERTY...LUMPKIN...CHESTATEE...
  OSCARVILLE AND WAR HILL PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...EXCESSIVE CLOUD TO 
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS 
IMMEDIATELY! REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE 
ENOUGH TO BE STRUCK BY LIGHTNING.

IF YOU SEE WIND DAMAGE...HAIL OR FLOODING...WAIT UNTIL THE STORM HAS
PASSED...AND THEN CALL THE NATIONAL WEATHER SERVICE TOLL FREE AT 1 8
6 6 7 6 3 4 4 6 6. YOU CAN ALSO TWEET YOUR REPORT USING HASHTAG GAWX.

&&

LAT...LON 3442 8399 3440 8397 3439 8398 3435 8398
      3430 8393 3427 8395 3424 8395 3423 8397
      3422 8396 3420 8399 3424 8426 3445 8426
      3446 8408
TIME...MOT...LOC 0144Z 267DEG 12KT 3435 8414

$$

16

The office that day

Everything else NWS Atlanta, GA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 10, 8:54 PM EDT	Special Weather Statement	FFC	Bartow	36 min
Aug 10, 9:18 PM EDT	Severe Thunderstorm Warning	FFC	Bartow, Cherokee	42 min
Aug 10, 9:27 PM EDT	Special Weather Statement	FFC	Hall	33 min
Aug 10, 9:29 PM EDT	Special Weather Statement	FFC	Forsyth	31 min
Aug 10, 9:58 PM EDT	Special Weather Statement	FFC	Hall	32 min
Aug 10, 11:37 PM EDT	Special Weather Statement	FFC	Carroll, Heard	23 min
Aug 11, 1:52 AM EDT	Special Weather Statement	FFC	Forsyth, Gwinnett	38 min
Aug 11, 2:53 AM EDT	Special Weather Statement	FFC	Barrow, Gwinnett	37 min
Aug 11, 2:55 AM EDT	Special Weather Statement	FFC	Fannin, Union	50 min
Aug 11, 5:03 AM EDT	Special Weather Statement	FFC	Chattahoochee, Marion	42 min
Aug 11, 6:34 AM EDT	Special Weather Statement	FFC	Schley, Sumter	41 min
Aug 11, 1:58 PM EDT	Special Weather Statement	FFC	Bibb, Crawford, Peach	32 min
Aug 11, 2:52 PM EDT	Special Weather Statement	FFC	Warren	8 min
Aug 11, 4:46 PM EDT	Special Weather Statement	FFC	Emanuel	29 min

Nearby

Severe Thunderstorm Warnings in Georgia, 2012 Every severe thunderstorm warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.