Alert archive / Georgia / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 9, NWS Atlanta, GA

January 11, 20207 counties in Georgia

NWS Atlanta, GA issued this severe thunderstorm warning at Jan 11, 2020, 5:24 PM EST for 7 counties in Georgia. It was in force for 51 min. 12 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: Jan 11, 2020, 5:24 PM EST (22:24 UTC)
Expired: Jan 11, 2020, 6:15 PM EST
In force: 51 min
Issued by: NWS Atlanta, GA
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Clayton County, GA, DeKalb County, GA, Fayette County, GA, Forsyth County, GA, Fulton County, GA, Gwinnett County, GA, Hall County, GA

The radar

The Atlanta radar (KFFC), 65 km from the middle of the area, began a volume at 22:25 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
Jan 11, 5:26 PM EST	TSTM WND DMG	3 Nnw Lake Lanier Islan, GA	A TREE WAS REPORTED DOWN NEAR THE INTERSECTION OF CHESTNUT HILL RD AND LANIER DR. TIME INDICATED BY RADAR.
Jan 11, 5:27 PM EST	TSTM WND DMG	Cascade Heights, GA	TREE DOWN ON A POWERLINE ON VENETIAN DRIVE NEAR CASCADE ELEMENTARY. REPORT RELAYED BY 11 ALIVE TV.
Jan 11, 5:29 PM EST	TSTM WND DMG	1 E Brookwood, GA	POWERLINE REPORTED DOWN NEAR THE INTERSECTION OF BAGLEY DR AND MATHIS AIRPORT RD. TIME INDICATED BY RADAR.
Jan 11, 5:32 PM EST	TSTM WND DMG	1 N Chestatee, GA	MULTIPLE TREES REPORTED DOWN NEAR THE INTERSECTION OF MATT HWY AND SEABOLT DR. TIME INDICATED BY RADAR.
Jan 11, 5:34 PM EST	TSTM WND DMG	Sugar Hill, GA	ONE TREE DOWNED ONTO VEHICLE AND ANOTHER TREE DOWNED ACROSS ROADWAY.
Jan 11, 5:34 PM EST	TSTM WND DMG	Sugar Hill, GA	ONE TREE DOWNED ONTO VEHICLE AND ANOTHER TREE DOWNED ACROSS ROADWAY... BOTH ON HILLCREST DRIVE.
Jan 11, 5:35 PM EST	TSTM WND DMG	2 Nw Lake Lanier Island, GA	TREES WERE REPORTED DOWN NEAR THE INTERSECTION OF DOGWOOD TRAIL AND LANIER DR. TIME INDICATED BY RADAR.
Jan 11, 5:39 PM EST	TSTM WND DMG	2 Wnw Johns Creek, GA	TREE FELL ON POWERLINES AND THEN A HOME WHICH STARTED A FIRE THAT GUTTED THE STRUCTURE. WSBTV RELAYED THE REPORT.
Jan 11, 5:41 PM EST	TSTM WND DMG	1 Ene Brookhaven, GA	TREE DOWN ON HOME NEAR THE INTERSECTION OF REDDING WAY AND REDDING ROAD. WSBTV RELAYED THE REPORT.
Jan 11, 5:51 PM EST	TSTM WND DMG	1 Ene Grant Park-Zoo At, GA	A TREE DOWN ON A POWERLINE BLOCKING THE ROADWAY NEAR THE INTERSECTION OF GLENWOOD AVENUE SE AND MORELAND AVENUE SE. REPORT RELAYED BE 11 ALIVE TV.
Jan 11, 5:54 PM EST	TSTM WND DMG	Decatur, GA	DEKALB COUNTY EMERGENCY MANAGEMENT REPORTS MULTIPLE TREES DOWN ACROSS THE COUNTY.
Jan 11, 5:56 PM EST	TSTM WND DMG	3 E Oscarville, GA	SEVERAL REPORTS OF TREES AND POWERLINES DOWN IN THE VACINITY OF THE BALUS CREEK BOAT RAMP, SE OF BROWNS RIDGE RD.

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
Jan 11, 1:42 PM EST	Tornado Watch	SPC	7 hr

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 10.4 hours before the alert went out and 62 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: 13 J/kg
Mixed-layer CIN: -26 J/kg
Mixed-layer LCL: 557 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 417 m²/s²
0-3 km storm-relative helicity: 450 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

508 
WUUS52 KFFC 112224
SVRFFC
GAC063-089-113-117-121-135-139-112315-
/O.NEW.KFFC.SV.W.0009.200111T2224Z-200111T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Peachtree City GA
524 PM EST Sat Jan 11 2020

The National Weather Service in Peachtree City has issued a

* Severe Thunderstorm Warning for...
  DeKalb County in north central Georgia...
  Northwestern Fayette County in north central Georgia...
  Forsyth County in north central Georgia...
  Gwinnett County in north central Georgia...
  Southwestern Hall County in north central Georgia...
  Fulton County in north central Georgia...
  Clayton County in north central Georgia...

* Until 615 PM EST.

* At 523 PM EST, severe thunderstorms were located along a line
  extending from near Hollis Lathem Reservoir to near Palmetto,
  moving east at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Atlanta, Gainesville, Lawrenceville, Decatur, Cumming, Jonesboro,
  Sandy Springs, Roswell, Johns Creek, Alpharetta, Dunwoody, East
  Point, Milton, Duluth, Union City, Sugar Hill, Forest Park,
  Snellville, Suwanee and Riverdale.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM EST for north central
and west central Georgia.

For your protection move to an interior room on the lowest floor of a
building.

This is a DANGEROUS SITUATION. These storms are producing widespread 
wind damage across north Georgia. SEEK SHELTER NOW inside a sturdy 
structure and stay away from windows! 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 or tweet 
us your report at NWSATLANTA.

&&

LAT...LON 3433 8380 3391 8396 3365 8420 3363 8424
      3365 8425 3365 8428 3359 8425 3352 8431
      3351 8474 3379 8451 3383 8446 3393 8443
      3398 8438 3401 8440 3419 8431 3419 8426
      3433 8425
TIME...MOT...LOC 2223Z 275DEG 35KT 3436 8420 3350 8471 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

1 follow-up statement

173 
WWUS52 KFFC 112315 RRA
SVSFFC

Severe Weather Statement
National Weather Service Peachtree City GA
615 PM EST Sat Jan 11 2020

GAC063-089-113-117-121-135-139-112325-
/O.EXP.KFFC.SV.W.0009.000000T0000Z-200111T2315Z/
DeKalb GA-Fayette GA-Forsyth GA-Gwinnett GA-Hall GA-Fulton GA-
Clayton GA-
615 PM EST Sat Jan 11 2020

...THE SEVERE THUNDERSTORM WARNING FOR DEKALB...NORTHWESTERN
FAYETTE...FORSYTH...GWINNETT...SOUTHWESTERN HALL...FULTON AND CLAYTON
COUNTIES HAS EXPIRED...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been allowed to expire. A severe 
thunderstorm warning continues downstream. 

A Tornado Watch remains in effect until 900 PM EST for north central
and west central Georgia.

LAT...LON 3433 8380 3391 8396 3365 8420 3363 8424
      3365 8425 3365 8428 3359 8425 3352 8431
      3351 8474 3379 8451 3383 8446 3393 8443
      3398 8438 3401 8440 3419 8431 3419 8426
      3433 8425
TIME...MOT...LOC 2315Z 275DEG 35KT 3431 8360 3346 8411 

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Jan 11, 10:28 AM EST	High Wind Warning	FFC	Catoosa, Chattooga, Dade, Dawson, Fannin, Floyd and 10 more	11 hr
Jan 11, 3:00 PM EST	Severe Thunderstorm Warning	FFC	Catoosa, Chattooga, Dade, Floyd, Walker, Whitfield	45 min
Jan 11, 3:42 PM EST	Severe Thunderstorm Warning	FFC	Bartow, Catoosa, Chattooga, Floyd, Gordon, Murray and 2 more	48 min
Jan 11, 3:53 PM EST	Severe Thunderstorm Warning	FFC	Carroll, Haralson, Polk	52 min
Jan 11, 4:16 PM EST	Severe Thunderstorm Warning	FFC	Carroll, Heard	44 min
Jan 11, 4:19 PM EST	Severe Thunderstorm Warning	FFC	Bartow, Cherokee, Fannin, Gilmer, Gordon, Murray and 3 more	41 min
Jan 11, 4:47 PM EST	Severe Thunderstorm Warning	FFC	Chattahoochee, Coweta, Harris, Heard, Meriwether, Muscogee and 2 more	43 min
Jan 11, 4:51 PM EST	Severe Thunderstorm Warning	FFC	Bartow, Carroll, Cherokee, Clayton, Cobb, Douglas and 2 more	39 min
Jan 11, 4:53 PM EST	Severe Thunderstorm Warning	FFC	Dawson, Fannin, Gilmer, Lumpkin, Pickens, Union	52 min
Jan 11, 5:02 PM EST	Tornado Warning	FFC	Harris, Muscogee	28 min
Jan 11, 5:27 PM EST	Severe Thunderstorm Warning	FFC	Dawson, Hall, Lumpkin, Towns, Union, White	48 min
Jan 11, 5:29 PM EST	Severe Thunderstorm Warning	FFC	Clayton, Coweta, Fayette, Harris, Henry, Lamar and 5 more	46 min
Jan 11, 5:34 PM EST	Severe Thunderstorm Warning	FFC	Chattahoochee, Marion, Stewart, Talbot	41 min
Jan 11, 5:57 PM EST	Severe Thunderstorm Warning	FFC	Chattahoochee, Marion, Stewart, Webster	48 min
Jan 11, 6:08 PM EST	Severe Thunderstorm Warning	FFC	Crawford, Lamar, Monroe, Taylor, Upson	52 min
Jan 11, 6:10 PM EST	Severe Thunderstorm Warning	FFC	Banks, Barrow, Gwinnett, Hall, Jackson, Walton	50 min
Jan 11, 6:12 PM EST	Severe Thunderstorm Warning	FFC	Butts, DeKalb, Henry, Jasper, Newton, Rockdale and 2 more	48 min
Jan 11, 6:17 PM EST	Severe Thunderstorm Warning	FFC	Chattahoochee, Marion, Taylor	43 min
Jan 11, 6:41 PM EST	Severe Thunderstorm Warning	FFC	Macon, Marion, Schley, Sumter, Taylor, Webster	34 min
Jan 11, 6:45 PM EST	Special Weather Statement	FFC	Clarke, Greene, Madison, Morgan, Oconee, Oglethorpe	45 min
Jan 11, 6:49 PM EST	Special Weather Statement	FFC	Baldwin, Jasper, Jones, Putnam	41 min
Jan 11, 6:52 PM EST	Severe Thunderstorm Warning	FFC	Jasper, Morgan, Putnam	38 min
Jan 11, 6:58 PM EST	Severe Thunderstorm Warning	FFC	Bibb, Crawford, Houston, Peach, Taylor, Twiggs	47 min

Nearby

Severe Thunderstorm Warnings in Georgia, 2020 Every severe thunderstorm warning in 2020

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.