Alert archive / Georgia / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 178, NWS Atlanta, GA

May 18, 2017Hall County, Georgia

NWS Atlanta, GA issued this severe thunderstorm warning at May 18, 2017, 3:21 PM EDT for Hall County, Georgia. It was in force for 28 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
May 18, 2017, 3:21 PM EDT (19:21 UTC)
Expired
May 18, 2017, 3:49 PM EDT
In force
28 min
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Hall County, GA

The radar

The Atlanta radar (KFFC), 140 km from the middle of the area, began a volume at 19:22 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, 7.4 hours before the alert went out and 136 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 2017-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 114 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 2017-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 71 square meters per square second.19395878Sfc1 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
114 J/kg
Mixed-layer CIN
-215 J/kg
Mixed-layer LCL
1009 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
71 m²/s²
0-3 km storm-relative helicity
109 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

381 
WUUS52 KFFC 181921
SVRFFC
GAC139-182000-
/O.NEW.KFFC.SV.W.0178.170518T1921Z-170518T2000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Peachtree City GA
321 PM EDT THU MAY 18 2017

The National Weather Service in Peachtree City has issued a

* Severe Thunderstorm Warning for...
  Eastern Hall County in north central Georgia...

* Until 400 PM EDT

* At 321 PM EDT, a severe thunderstorm was located near Gainesville,
  moving northeast at 10 mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  Gainesville, Lula, Gillsville and Candler. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 3443 8362 3442 8362 3442 8364 3440 8366
      3436 8367 3435 8365 3432 8365 3430 8362
      3418 8376 3431 8388 3449 8366 3449 8365
TIME...MOT...LOC 1921Z 235DEG 7KT 3429 8375 

HAIL...<.75IN
WIND...60MPH
 
$$
1 follow-up statement
574 
WWUS52 KFFC 181949
SVSFFC

Severe Weather Statement
National Weather Service Peachtree City GA
349 PM EDT THU MAY 18 2017

GAC139-181959-
/O.CAN.KFFC.SV.W.0178.000000T0000Z-170518T2000Z/
Hall GA-
349 PM EDT THU MAY 18 2017

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN HALL COUNTY IS
CANCELLED...
                
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 has been cancelled.

LAT...LON 3443 8362 3442 8362 3442 8364 3440 8366
      3436 8367 3435 8365 3432 8365 3430 8362
      3418 8376 3431 8388 3449 8366 3449 8365
TIME...MOT...LOC 1947Z 235DEG 7KT 3432 8370 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 18, 3:14 PM EDTSpecial Weather StatementFFCHall31 min
May 18, 4:39 PM EDTSevere Thunderstorm WarningFFCBanks, Madison32 min
May 18, 5:58 PM EDTSpecial Weather StatementFFCForsyth32 min
May 18, 6:10 PM EDTSpecial Weather StatementFFCCherokee35 min

Nearby

Severe Thunderstorm Warnings in Georgia, 2017Every severe thunderstorm warning in 2017

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.