Alert archive / Florida / Mesoscale Discussions in 2015

Mesoscale Discussion 1641

August 8, 201513 counties in Alabama; 15 counties in Florida; 5 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Aug 8, 2015, 1:31 PM CDT for 13 counties in Alabama; 15 counties in Florida; 5 counties in Georgia. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued: Aug 8, 2015, 1:31 PM CDT (18:31 UTC)
Expired: Aug 8, 2015, 2:30 PM CDT
In force: 59 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 33 counties

Baldwin County, AL, Butler County, AL, Clarke County, AL, Coffee County, AL, Conecuh County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Escambia County, AL, Geneva County, AL, Houston County, AL, Monroe County, AL, Washington County, AL, Bay County, FL, Calhoun County, FL, Escambia County, FL, Gadsden County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Jefferson County, FL, Leon County, FL, Liberty County, FL, Okaloosa County, FL, Santa Rosa County, FL, Wakulla County, FL, Walton County, FL, Washington County, FL, Decatur County, GA, Early County, GA, Grady County, GA, Miller County, GA, Seminole County, GA

The radar

The Eglin Afb radar (KEVX), 37 km from the middle of the area, began a volume at 18:31 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 12:00Z, 6.5 hours before the alert went out and 172 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: 709 J/kg
Mixed-layer CIN: -89 J/kg
Mixed-layer LCL: 1016 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 35 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 8, 9:47 AM CDT	Mesoscale Discussion	SPC	DeSoto, Hardee, Hernando, Highlands, Hillsborough, Indian River and 9 more	2 hr

Nearby

Mesoscale Discussions in Florida, 2015 Mesoscale Discussions in Alabama, 2015 Mesoscale Discussions in Georgia, 2015 Every mesoscale discussion in 2015

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.