Alert archive / Georgia / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 302, NWS Atlanta, GA

June 15, 2011Forsyth County, Hall County, Georgia

NWS Atlanta, GA issued this severe thunderstorm warning at Jun 15, 2011, 6:07 PM EDT for Forsyth County, Hall County, Georgia. It was in force for 38 min. 2 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: Jun 15, 2011, 6:07 PM EDT (22:07 UTC)
Expired: Jun 15, 2011, 6:45 PM EDT
In force: 38 min
Issued by: NWS Atlanta, GA
Area: Storm-based polygon

Counties Forsyth County, GA, Hall County, GA

The radar

The Atlanta radar (KFFC), 106 km from the middle of the area, began a volume at 22:10 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
Jun 15, 6:10 PM EDT	TSTM WND DMG	Cumming, GA	FORSYTH COUNTY 911 RELAYED REPORTS OF 15-20 DOWNED TREES IN AND AROUND FORSYTH. 15-20 POWERLINES WERE ALSO REPORTED DOWNED...WITH 3-4 TRANSFORMER FIRES. SEVERAL HOUSE FIRES WERE ALSO REPORTED.
Jun 15, 6:22 PM EDT	HAIL 1	Cumming, GA

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jun 15, 12:52 PM EDT	Severe Thunderstorm Watch	SPC	9 hr

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 10.1 hours before the alert went out and 103 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: 227 J/kg
Mixed-layer CIN: -377 J/kg
Mixed-layer LCL: 1521 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 91 m²/s²
0-3 km storm-relative helicity: 127 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.9

Open this sounding in Storm Lab

The text

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

367 
WUUS52 KFFC 152207
SVRFFC
GAC117-139-152245-
/O.NEW.KFFC.SV.W.0302.110615T2207Z-110615T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
607 PM EDT WED JUN 15 2011

THE NATIONAL WEATHER SERVICE IN PEACHTREE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  FORSYTH COUNTY IN NORTH CENTRAL GEORGIA
  SOUTHWESTERN HALL COUNTY IN NORTH CENTRAL GEORGIA

* UNTIL 645 PM EDT

* AT 605 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZED HAIL...AND
  DAMAGING WINDS UP TO 60 MPH.  THIS STORM WAS LOCATED NEAR
  CUMMING...MOVING EAST AT 15 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  OAKWOOD...GAINESVILLE AND FLOWERY BRANCH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU SEE WIND DAMAGE...LARGE HAIL OR SIGNIFICANT 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.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM EDT
WEDNESDAY EVENING FOR NORTHERN GEORGIA.

&&

LAT...LON 3433 8382 3411 8384 3410 8386 3410 8388
      3417 8406 3412 8410 3414 8426 3433 8426
TIME...MOT...LOC 2207Z 275DEG 15KT 3423 8420

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 15, 1:26 PM EDT	Special Weather Statement	FFC	Catoosa	49 min
Jun 15, 1:34 PM EDT	Severe Thunderstorm Warning	FFC	Catoosa, Walker	41 min
Jun 15, 1:59 PM EDT	Special Weather Statement	FFC	Murray	31 min
Jun 15, 2:30 PM EDT	Special Weather Statement	FFC	Fannin	45 min
Jun 15, 3:42 PM EDT	Severe Thunderstorm Warning	FFC	Dade, Walker	48 min
Jun 15, 4:08 PM EDT	Special Weather Statement	FFC	Chattooga	52 min
Jun 15, 4:27 PM EDT	Special Weather Statement	FFC	Floyd	48 min
Jun 15, 4:33 PM EDT	Severe Thunderstorm Warning	FFC	Catoosa, Walker, Whitfield	42 min
Jun 15, 5:08 PM EDT	Special Weather Statement	FFC	Floyd, Polk	37 min
Jun 15, 5:16 PM EDT	Special Weather Statement	FFC	Gilmer, Murray	44 min
Jun 15, 5:17 PM EDT	Special Weather Statement	FFC	Cherokee	43 min
Jun 15, 5:32 PM EDT	Special Weather Statement	FFC	Cobb, Paulding	43 min
Jun 15, 5:33 PM EDT	Special Weather Statement	FFC	Pickens	27 min
Jun 15, 5:44 PM EDT	Severe Thunderstorm Warning	FFC	Floyd, Polk	37 min
Jun 15, 5:52 PM EDT	Severe Thunderstorm Warning	FFC	Cobb, Paulding	38 min
Jun 15, 6:00 PM EDT	Special Weather Statement	FFC	Forsyth	45 min
Jun 15, 6:15 PM EDT	Special Weather Statement	FFC	Towns	30 min
Jun 15, 6:19 PM EDT	Severe Thunderstorm Warning	FFC	Carroll, Douglas, Haralson, Paulding, Polk	41 min
Jun 15, 6:20 PM EDT	Special Weather Statement	FFC	White	10 min
Jun 15, 6:29 PM EDT	Special Weather Statement	FFC	Cobb	46 min
Jun 15, 6:37 PM EDT	Special Weather Statement	FFC	Polk	53 min
Jun 15, 6:45 PM EDT	Severe Thunderstorm Warning	FFC	Cobb, Douglas	45 min
Jun 15, 6:48 PM EDT	Special Weather Statement	FFC	Forsyth, Hall	42 min
Jun 15, 6:55 PM EDT	Special Weather Statement	FFC	Barrow, Gwinnett	50 min
Jun 15, 7:10 PM EDT	Severe Thunderstorm Warning	FFC	Clayton, DeKalb, Douglas, Fayette, Fulton	65 min
Jun 15, 7:29 PM EDT	Special Weather Statement	FFC	Clarke	31 min
Jun 15, 7:35 PM EDT	Special Weather Statement	FFC	Madison	25 min
Jun 15, 7:36 PM EDT	Special Weather Statement	FFC	Catoosa	39 min
Jun 15, 7:37 PM EDT	Severe Thunderstorm Warning	FFC	Gwinnett, Walton	53 min
Jun 15, 7:41 PM EDT	Special Weather Statement	FFC	Oconee	19 min
Jun 15, 7:51 PM EDT	Special Weather Statement	FFC	Polk	39 min
Jun 15, 7:53 PM EDT	Severe Thunderstorm Warning	FFC	Henry, Newton, Rockdale	67 min

Nearby

Severe Thunderstorm Warnings in Georgia, 2011 Every severe thunderstorm warning in 2011

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.