Alert archive / Georgia / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 142, NWS Atlanta, GA

June 21, 2018Madison County, Oglethorpe County, Georgia

NWS Atlanta, GA issued this severe thunderstorm warning at Jun 21, 2018, 2:31 PM EDT for Madison County, Oglethorpe County, Georgia. It was in force for 29 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 21, 2018, 2:31 PM EDT (18:31 UTC)
Expired
Jun 21, 2018, 3:00 PM EDT
In force
29 min
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Madison County, GA, Oglethorpe County, GA

The radar

The Greer radar (KGSP), 122 km from the middle of the area, began a volume at 18:31 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.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 6.5 hours before the alert went out and 152 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 2018-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 354 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 2018-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 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
354 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
1180 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
90 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

As transmitted.

905 
WUUS52 KFFC 211831
SVRFFC
GAC195-221-211900-
/O.NEW.KFFC.SV.W.0142.180621T1831Z-180621T1900Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Peachtree City GA
231 PM EDT THU JUN 21 2018

The National Weather Service in Peachtree City has issued a

* Severe Thunderstorm Warning for...
  Northern Oglethorpe County in northeastern Georgia...
  Southeastern Madison County in northeastern Georgia...

* Until 300 PM EDT.

* At 231 PM EDT, a severe thunderstorm was located over Smithonia, or
  8 miles south of Danielsville, moving east at 25 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Comer, Winterville, Colbert, Carlton, Hull, Diamond Hill,
  Smithonia, Watson Mill Bridge State Park, Point Peter and Paoli.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. 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 or tweet us your report at NWSATLANTA.

&&

LAT...LON 3397 8285 3396 8327 3398 8327 3400 8326
      3401 8329 3407 8330 3412 8304 3411 8303
      3410 8304 3408 8300 3405 8299 3403 8293
      3401 8294 3401 8291
TIME...MOT...LOC 1831Z 264DEG 21KT 3401 8319 

HAIL...1.00IN
WIND...60MPH
 
$$
1 follow-up statement
629 
WWUS52 KFFC 211851
SVSFFC

Severe Weather Statement
National Weather Service Peachtree City GA
251 PM EDT THU JUN 21 2018

GAC195-221-211900-
/O.EXP.KFFC.SV.W.0142.000000T0000Z-180621T1900Z/
Oglethorpe GA-Madison GA-
251 PM EDT THU JUN 21 2018

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN OGLETHORPE AND
SOUTHEASTERN MADISON COUNTIES WILL EXPIRE AT 300 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.

LAT...LON 3397 8285 3396 8327 3398 8327 3400 8326
      3401 8329 3407 8330 3412 8304 3411 8303
      3410 8304 3408 8300 3405 8299 3403 8293
      3401 8294 3401 8291
TIME...MOT...LOC 1850Z 264DEG 21KT 3402 8306 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 9:05 PM EDTSpecial Weather StatementFFCToombs25 min
Jun 21, 2:27 PM EDTSpecial Weather StatementFFCMadison33 min
Jun 21, 3:34 PM EDTSpecial Weather StatementFFCCoweta26 min
Jun 21, 3:38 PM EDTSpecial Weather StatementFFCGwinnett37 min
Jun 21, 3:57 PM EDTSpecial Weather StatementFFCMorgan, Newton33 min
Jun 21, 4:04 PM EDTSpecial Weather StatementFFCFayette26 min
Jun 21, 4:46 PM EDTSpecial Weather StatementFFCMadison14 min
Jun 21, 5:43 PM EDTSpecial Weather StatementFFCTalbot32 min
Jun 21, 7:01 PM EDTSpecial Weather StatementFFCGlascock14 min

Nearby

Severe Thunderstorm Warnings in Georgia, 2018Every severe thunderstorm warning in 2018

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; radar from the NEXRAD Level II archive.