Alert archive / Florida / Mesoscale Discussions in 2014

Mesoscale Discussion 487

April 30, 20146 counties in Florida; 5 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2014, 1:39 AM CDT for 6 counties in Florida; 5 counties in Georgia. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: Apr 30, 2014, 1:39 AM CDT (06:39 UTC)
Expired: Apr 30, 2014, 3:15 AM CDT
In force: 96 min
Issued by: the Storm Prediction Center

Counties Bay County, FL, Calhoun County, FL, Gadsden County, FL, Jackson County, FL, Leon County, FL, Liberty County, FL, Decatur County, GA, Early County, GA, Grady County, GA, Miller County, GA, Seminole County, GA

The radar

The Tallahassee radar (KTLH), 73 km from the middle of the area, began a volume at 06:39 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, 6.7 hours before the alert went out and 75 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: 124 J/kg
Mixed-layer CIN: -255 J/kg
Mixed-layer LCL: 1698 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 160 m²/s²
0-3 km storm-relative helicity: 229 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Apr 29, 9:01 PM CDT	Mesoscale Discussion	SPC	Escambia, Okaloosa, Santa Rosa	59 min
Apr 29, 9:56 PM CDT	Tornado Watch	SPC	Bay, Gulf, Holmes, Walton, Washington	4 hr
Apr 29, 11:29 PM CDT	Mesoscale Discussion	SPC	Bay, Holmes, Walton, Washington	2 hr
Apr 30, 12:45 AM CDT	Tornado Watch	SPC	Bay, Calhoun, Franklin, Gadsden, Gulf, Holmes and 7 more	8 hr
Apr 30, 4:15 AM CDT	Mesoscale Discussion	SPC	Bay, Calhoun, Escambia, Gadsden, Gulf, Jefferson and 8 more	2 hr
Apr 30, 6:17 AM CDT	Mesoscale Discussion	SPC	Franklin, Gulf, Liberty, Wakulla	88 min
Apr 30, 8:58 AM CDT	Mesoscale Discussion	SPC	Dixie, Franklin, Jefferson, Lafayette, Leon, Liberty and 2 more	62 min
Apr 30, 1:16 PM CDT	Mesoscale Discussion	SPC	Citrus, Flagler, Hernando, Lake, Marion, Putnam and 3 more	119 min

Nearby

Mesoscale Discussions in Florida, 2014 Mesoscale Discussions in Georgia, 2014 Every mesoscale discussion in 2014

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.