Alert archive / Georgia / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 1, NWS Atlanta, GA

March 1, 20185 counties in Georgia

NWS Atlanta, GA issued this severe thunderstorm warning at Mar 1, 2018, 11:17 AM EST for 5 counties in Georgia. It was in force for 28 min. 4 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
Mar 1, 2018, 11:17 AM EST (16:17 UTC)
Expired
Mar 1, 2018, 11:45 AM EST
In force
28 min
Issued by
NWS Atlanta, GA
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

Counties Cobb County, GA, DeKalb County, GA, Forsyth County, GA, Fulton County, GA, Gwinnett County, GA

The radar

The Atlanta radar (KFFC), 67 km from the middle of the area, began a volume at 16:20 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
Mar 1, 11:21 AM ESTTSTM WND DMG2 W Marietta, GA2 TREES DOWN NEAR INTERSECTION OF BURNT HICKORY RD AND POLK ST
Mar 1, 11:21 AM ESTTSTM WND DMG2 W Marietta, GA
Mar 1, 11:32 AM ESTTSTM WND GST 591 Ssw Dobbins Air Reser, GAKMGE GUSTED TO 51KTS
Mar 1, 11:53 AM ESTTSTM WND DMG2 Ssw Lilburn, GAONE TREE DOWN NEAR THE INTERSECTION OF HARMONY GROVE ROAD AND ROSSER COURT.

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, 4.3 hours before the alert went out and 66 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 2018-03-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 212 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 2018-03-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 232 square meters per square second.1939587897Sfc1 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
212 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
572 m above ground
0-6 km bulk shear
66 kt
0-1 km storm-relative helicity
232 m²/s²
0-3 km storm-relative helicity
241 m²/s²
Significant tornado parameter
0.3
Supercell composite
1.7

Open this sounding in Storm Lab

The text

As transmitted.

866 
WUUS52 KFFC 011617
SVRFFC
GAC067-089-117-121-135-011645-
/O.NEW.KFFC.SV.W.0001.180301T1617Z-180301T1645Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Peachtree City GA
1117 AM EST THU MAR 1 2018

The National Weather Service in Peachtree City has issued a

* Severe Thunderstorm Warning for...
  Northwestern DeKalb County in north central Georgia...
  Southwestern Forsyth County in north central Georgia...
  Northern Cobb County in north central Georgia...
  Northwestern Gwinnett County in north central Georgia...
  Northeastern Fulton County in north central Georgia...

* Until 1145 AM EST

* At 1116 AM EST, a severe thunderstorm was located over Due West, or
  near Marietta, moving east at 55 mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

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

* Locations impacted include...
  Atlanta, Marietta, Sandy Springs, Roswell, Johns Creek, Alpharetta,
  Smyrna, Dunwoody, Kennesaw, Duluth, Acworth, Sugar Hill,
  Snellville, Suwanee, Lilburn, Chamblee, Norcross, Doraville,
  Berkeley Lake and Fair Oaks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This thunderstorm can produce a brief tornado and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. This storm may cause serious injury and significant
property damage.

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 3389 8468 3403 8468 3413 8406 3385 8403
TIME...MOT...LOC 1616Z 266DEG 47KT 3396 8462 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$
1 follow-up statement
991 
WWUS52 KFFC 011641
SVSFFC

Severe Weather Statement
National Weather Service Peachtree City GA
1141 AM EST THU MAR 1 2018

GAC067-089-117-121-135-011651-
/O.EXP.KFFC.SV.W.0001.000000T0000Z-180301T1645Z/
DeKalb GA-Forsyth GA-Cobb GA-Gwinnett GA-Fulton GA-
1141 AM EST THU MAR 1 2018

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN DEKALB...
SOUTHWESTERN FORSYTH...NORTHERN COBB...NORTHWESTERN GWINNETT AND
NORTHEASTERN FULTON COUNTIES WILL EXPIRE AT 1145 AM EST...
                
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.  However gusty winds
are still possible with this thunderstorm.

LAT...LON 3389 8468 3403 8468 3413 8406 3385 8403
TIME...MOT...LOC 1641Z 266DEG 47KT 3398 8425 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 28, 8:51 PM ESTSpecial Weather StatementFFCWalker39 min
Feb 28, 9:26 PM ESTSpecial Weather StatementFFCChattooga49 min
Feb 28, 10:36 PM ESTRiver Flood WarningFFCWalker24 hr
Feb 28, 10:51 PM ESTSpecial Weather StatementFFCChattooga, Walker39 min
Feb 28, 11:23 PM ESTRiver Flood WarningFFCMurray, Whitfield55 hr
Feb 28, 11:30 PM ESTSpecial Weather StatementFFCChattooga30 min
Feb 28, 11:31 PM ESTRiver Flood WarningFFCWhitfield4 days
Feb 28, 11:35 PM ESTRiver Flood WarningFFCCatoosa56 hr
Feb 28, 11:54 PM ESTSpecial Weather StatementFFCGordon, Pickens51 min
Mar 1, 3:43 AM ESTWind AdvisoryFFCBaldwin, Bibb, Bleckley, Butts, Chattahoochee, Clarke and 58 more14 hr
Mar 1, 4:50 AM ESTRiver Flood WarningFFCCatoosa25 hr
Mar 1, 10:17 AM ESTSpecial Weather StatementFFCBartow, Haralson, Polk43 min
Mar 1, 10:49 AM ESTSpecial Weather StatementFFCCarroll, Cherokee, Cobb, Douglas, Forsyth, Fulton and 2 more41 min
Mar 1, 11:29 AM ESTSpecial Weather StatementFFCCarroll, DeKalb, Douglas, Forsyth, Fulton, Gwinnett and 2 more46 min
Mar 1, 12:03 PM ESTSpecial Weather StatementFFCBarrow, Clayton, Coweta, DeKalb, Fayette, Gwinnett and 6 more42 min
Mar 1, 1:11 PM ESTSpecial Weather StatementFFCMorgan, Newton34 min
Mar 1, 1:37 PM ESTSpecial Weather StatementFFCButts, Jasper23 min
Mar 1, 2:14 PM ESTSpecial Weather StatementFFCTalbot, Upson31 min
Mar 1, 2:42 PM ESTSpecial Weather StatementFFCBibb, Crawford, Jones, Monroe, Upson48 min
Mar 1, 2:49 PM ESTSpecial Weather StatementFFCBaldwin, Hancock26 min
Mar 1, 3:13 PM ESTSpecial Weather StatementFFCGlascock, Jefferson47 min
Mar 1, 3:17 PM ESTSpecial Weather StatementFFCHouston, Macon, Marion, Peach43 min
Mar 1, 3:19 PM ESTSpecial Weather StatementFFCBaldwin, Bibb, Twiggs, Washington, Wilkinson41 min
Mar 1, 3:23 PM ESTSevere Thunderstorm WarningFFCBibb, Laurens, Twiggs, Wilkinson37 min
Mar 1, 3:55 PM ESTSpecial Weather StatementFFCJefferson, Johnson, Washington, Wilkinson50 min
Mar 1, 4:35 PM ESTSpecial Weather StatementFFCEmanuel25 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.