Alert archive / Georgia / Mesoscale Discussions in 2018

Mesoscale Discussion 64

February 11, 2018Henry County, Houston County, Alabama; 8 counties in Florida; 16 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Feb 11, 2018, 3:16 AM CST for Henry County, Houston County, Alabama; 8 counties in Florida; 16 counties in Georgia. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued: Feb 11, 2018, 3:16 AM CST (09:16 UTC)
Expired: Feb 11, 2018, 4:45 AM CST
In force: 89 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 26 counties

Henry County, AL, Houston County, AL, Bay County, FL, Calhoun County, FL, Gadsden County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Liberty County, FL, Washington County, FL, Baker County, GA, Calhoun County, GA, Chattahoochee County, GA, Clay County, GA, Decatur County, GA, Early County, GA, Marion County, GA, Miller County, GA, Quitman County, GA, Randolph County, GA, Schley County, GA, Seminole County, GA, Stewart County, GA, Sumter County, GA, Terrell County, GA, Webster County, GA

The radar

The Eglin Afb radar (KEVX), 61 km from the middle of the area, began a volume at 09:19 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

Tallahassee Rgnl, FL (KTLH), launched 00:00Z, 9.3 hours before the alert went out and 105 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: 285 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 519 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 153 m²/s²
0-3 km storm-relative helicity: 171 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.5

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.

Issued	Product	Office	Counties	Lasted
Feb 10, 8:29 PM CST	Mesoscale Discussion	SPC	Autauga, Baldwin, Bibb, Bullock, Butler, Chilton and 20 more	3 hr

Nearby

Mesoscale Discussions in Georgia, 2018 Mesoscale Discussions in Florida, 2018 Mesoscale Discussions in Alabama, 2018 Every mesoscale discussion 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.