Alert archive / Georgia / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 111, NWS Atlanta, GA

May 17, 2012Forsyth County, Gwinnett County, Hall County, Georgia

NWS Atlanta, GA issued this severe thunderstorm warning at May 17, 2012, 6:50 PM EDT for Forsyth County, Gwinnett County, Hall County, Georgia. It was in force for 40 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
May 17, 2012, 6:50 PM EDT (22:50 UTC)
Expired
May 17, 2012, 7:30 PM EDT
In force
40 min
Issued by
NWS Atlanta, GA
Area
Storm-based polygon

Counties Forsyth County, GA, Gwinnett County, GA, Hall County, GA

The radar

The Atlanta radar (KFFC), 97 km from the middle of the area, began a volume at 22:53 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

TimeReportWhereRemark
May 17, 6:55 PM EDTHAIL 0.254 Ne Cumming, GAPEA SIZED HAIL AND ONE LARGE TREE PUSHED OVER OFF BROWNE CIRCLE ROAD.
May 17, 7:00 PM EDTHAIL 0.252 Nw Cumming, GAPEA SIZED HAIL AND TREE LIMBS BLOWN DOWN NEAR THE INTERSECTION OF GEORGIA HIGHWAYS 20 AND 306.
May 17, 7:05 PM EDTTSTM WND DMG3 Ene Cumming, GAMULTIPLE TREES BLOWN DOWN OFF OF CATALINA DRIVE. ONE TREE IS ON A HOUSE.

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 12:00Z, 10.8 hours before the alert went out and 93 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, Peachtre/Fal Fld, GA at 12:00Z on 2012-05-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 257 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peachtre/Fal Fld, GA at 12:00Z on 2012-05-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 square meters per square second.1939Sfc1 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
257 J/kg
Mixed-layer CIN
-80 J/kg
Mixed-layer LCL
1197 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
-26 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.

146 
WUUS52 KFFC 172250
SVRFFC
GAC117-135-139-172330-
/O.NEW.KFFC.SV.W.0111.120517T2250Z-120517T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
650 PM EDT THU MAY 17 2012

THE NATIONAL WEATHER SERVICE IN PEACHTREE CITY HAS ISSUED A

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

* UNTIL 730 PM EDT

* AT 648 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 SOUTH AT 10 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SUGAR
  HILL...REST HAVEN AND BUFORD.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS 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 3405 8391 3407 8418 3408 8419 3410 8423
      3429 8416 3429 8400
TIME...MOT...LOC 2250Z 008DEG 8KT 3425 8409

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 16, 8:04 PM EDTSpecial Weather StatementFFCPulaski41 min
May 16, 8:10 PM EDTSpecial Weather StatementFFCGreene50 min
May 16, 8:26 PM EDTSpecial Weather StatementFFCDooly49 min
May 16, 8:44 PM EDTSpecial Weather StatementFFCDooly, Pulaski61 min
May 16, 8:52 PM EDTSpecial Weather StatementFFCGreene53 min
May 16, 9:46 PM EDTSpecial Weather StatementFFCCrisp, Wilcox59 min
May 16, 10:19 PM EDTSpecial Weather StatementFFCCrisp41 min
May 16, 11:12 PM EDTSpecial Weather StatementFFCCrisp48 min
May 17, 11:44 AM EDTSpecial Weather StatementFFCBibb, Bleckley, Twiggs31 min
May 17, 12:40 PM EDTSpecial Weather StatementFFCDooly50 min
May 17, 12:59 PM EDTSevere Thunderstorm WarningFFCDooly, Houston, Macon46 min
May 17, 1:44 PM EDTSpecial Weather StatementFFCCrisp, Dooly61 min
May 17, 2:32 PM EDTSpecial Weather StatementFFCSumter43 min
May 17, 2:43 PM EDTSpecial Weather StatementFFCTaylor47 min
May 17, 2:45 PM EDTSpecial Weather StatementFFCMorgan45 min
May 17, 3:23 PM EDTSpecial Weather StatementFFCMorgan67 min
May 17, 3:30 PM EDTSevere Thunderstorm WarningFFCWilkes26 min
May 17, 3:59 PM EDTSpecial Weather StatementFFCHancock, Taliaferro, Warren, Wilkes31 min
May 17, 4:50 PM EDTSpecial Weather StatementFFCBaldwin, Glascock, Greene, Hancock, Jefferson, Madison and 3 more25 min
May 17, 5:37 PM EDTSpecial Weather StatementFFCBaldwin, Jefferson, Johnson, Wilkinson53 min
May 17, 5:49 PM EDTSevere Thunderstorm WarningFFCJones41 min
May 17, 6:14 PM EDTSpecial Weather StatementFFCForsyth, Hall46 min
May 17, 6:24 PM EDTSpecial Weather StatementFFCOconee, Walton51 min
May 17, 6:31 PM EDTSpecial Weather StatementFFCBleckley, Dodge, Emanuel, Laurens, Montgomery, Treutlen and 1 more44 min
May 17, 6:34 PM EDTSpecial Weather StatementFFCGilmer41 min
May 17, 6:45 PM EDTSpecial Weather StatementFFCTaylor45 min
May 17, 7:14 PM EDTSpecial Weather StatementFFCForsyth46 min
May 17, 7:38 PM EDTSpecial Weather StatementFFCFulton37 min
May 17, 7:42 PM EDTSevere Thunderstorm WarningFFCCobb, Fulton48 min
May 17, 7:46 PM EDTSevere Thunderstorm WarningFFCMarion, Stewart, Sumter, Webster44 min
May 17, 7:53 PM EDTSpecial Weather StatementFFCPickens37 min

Nearby

Severe Thunderstorm Warnings in Georgia, 2012Every 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.