Alert archive / Georgia / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 694, NWS Atlanta, GA

September 29, 1999Henry County, Spalding County, Georgia

NWS Atlanta, GA issued this severe thunderstorm warning at Sep 29, 1999, 10:19 AM EDT for Henry County, Spalding County, Georgia. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Sep 29, 1999, 10:19 AM EDT (14:19 UTC)
Expired
Sep 29, 1999, 10:55 AM EDT
In force
36 min
Issued by
NWS Atlanta, GA
Area
Whole counties

Counties Henry County, GA, Spalding County, GA

The radar

The Atlanta radar (KFFC), 32 km from the middle of the area, began a volume at 14:18 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, 2.3 hours before the alert went out and 26 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 1999-09-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1269 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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 1999-09-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 30 square meters per square second.193958Sfc1 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
1269 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
519 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
30 m²/s²
0-3 km storm-relative helicity
99 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.8

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KATL 291422 RRA
SVRATL
GAC151-255-291455-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1019 AM EDT WED SEP 29 1999

THE NATIONAL WEATHER SERVICE IN PEACHTREE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  HENRY COUNTY IN NORTHWESTERN GEORGIA
  SPALDING COUNTY IN NORTHWESTERN GEORGIA

* UNTIL 1055 AM EDT

* AT 1018 AM EDT... A SEVERE THUNDERSTORM WAS INDICATED BY DOPPLER
  RADAR  7 MILES SOUTH OF MCDONOUGH OR 4 MILES WEST OF LOCUST
  GROVE...MOVING NORTHEAST AT 20 MPH.

* SOME LOCATIONS IN OR NEAR THE PATH OF THIS STORM ARE...
  LOCUST GROVE...
  MCDONOUGH...
  OLA...

DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN AND DEADLY LIGHHTNING
ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS. IF YOU SEE DAMAGE OR
LARGE HAIL...CALL THE NATIONAL WEATHER SERVICE AT 770-486-1133 AT
EXTENSION 2 0 4.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 29, 2:23 PM EDTSevere Thunderstorm WarningFFCJefferson32 min

Nearby

Severe Thunderstorm Warnings in Georgia, 1999Every severe thunderstorm warning in 1999

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.