Alert archive / Georgia / Mesoscale Discussions in 2020

Mesoscale Discussion 366

April 12, 202024 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2020, 7:10 PM EDT for 24 counties in Georgia. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued
Apr 12, 2020, 7:10 PM EDT (23:10 UTC)
Expired
Apr 12, 2020, 8:15 PM EDT
In force
65 min
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 24 counties

Barrow County, GA, Bartow County, GA, Carroll County, GA, Chattooga County, GA, Cherokee County, GA, Cobb County, GA, Dawson County, GA, DeKalb County, GA, Douglas 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, Paulding County, GA, Pickens County, GA, Polk County, GA, Walker County, GA, White County, GA

The radar

The Atlanta radar (KFFC), 109 km from the middle of the area, began a volume at 23:15 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 11.2 hours before the alert went out and 109 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 2020-04-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2020-04-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 219 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1999 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
219 m²/s²
0-3 km storm-relative helicity
275 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 12, 7:22 PM EDTTornado WatchSPCBartow, Catoosa, Chattooga, Cherokee, Dade, Dawson and 9 more5 hr

Nearby

Mesoscale Discussions in Georgia, 2020Every mesoscale discussion in 2020

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.