Alert archive / Georgia / Dense Fog Advisories in 2012

Dense Fog Advisory 1, NWS Atlanta, GA

January 8, 201237 counties in Georgia

NWS Atlanta, GA issued this dense fog advisory at Jan 8, 2012, 4:36 AM EST for 37 counties in Georgia. It took effect at Jan 8, 2012, 5:00 AM EST. It was in force for 5 hr.

The area

The counties it named.

The facts

Issued: Jan 8, 2012, 4:36 AM EST (09:36 UTC)
In effect from: Jan 8, 2012, 5:00 AM EST
Expired: Jan 8, 2012, 10:00 AM EST
In force: 5 hr
Issued by: NWS Atlanta, GA

All 37 counties

Banks County, GA, Barrow County, GA, Bartow County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Clarke County, GA, Cobb County, GA, Dade County, GA, Dawson County, GA, DeKalb County, GA, Douglas County, GA, Fannin County, GA, Floyd County, GA, Forsyth County, GA, Fulton County, GA, Gilmer County, GA, Gordon County, GA, Gwinnett County, GA, Hall County, GA, Haralson County, GA, Jackson County, GA, Lumpkin County, GA, Madison County, GA, Murray County, GA, Oconee County, GA, Oglethorpe County, GA, Paulding County, GA, Pickens County, GA, Polk County, GA, Towns County, GA, Union County, GA, Walker County, GA, Walton County, GA, White County, GA, Whitfield County, GA

The radar

The Atlanta radar (KFFC), 104 km from the middle of the area, began a volume at 09:37 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 00:00Z, 9.6 hours before the alert went out and 102 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 145 J/kg
Mixed-layer CIN: -25 J/kg
Mixed-layer LCL: 975 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 122 m²/s²
0-3 km storm-relative helicity: 175 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this dense fog advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Atlanta, GA wrote its last area forecast discussion before this dense fog advisory went out at Jan 8, 4:19 AM EST, 17 minutes earlier.

Area forecast discussion, Jan 8, 4:19 AM EST, 17 minutes before

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Hazardous weather outlook, Jan 7, 9:30 PM EST, 7 hours 6 minutes before

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        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jan 7, 7:02 PM EST	Special Weather Statement	FFC	Barrow, Cobb, Gwinnett	58 min
Jan 8, 1:47 PM EST	Special Weather Statement	FFC	Troup	43 min
Jan 8, 6:46 PM EST	Dense Fog Advisory	FFC	Baldwin, Banks, Barrow, Bartow, Bibb, Bleckley and 90 more	15 hr

Nearby

Dense Fog Advisories in Georgia, 2012 Every dense fog advisory 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.