Alert archive / Kentucky / Mesoscale Discussions in 2015

Mesoscale Discussion 218

April 7, 201519 counties in Kentucky

The Storm Prediction Center issued this mesoscale discussion at Apr 7, 2015, 4:34 PM EDT for 19 counties in Kentucky. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued: Apr 7, 2015, 4:34 PM EDT (20:34 UTC)
Expired: Apr 7, 2015, 6:00 PM EDT
In force: 86 min
Issued by: the Storm Prediction Center

Counties Anderson County, KY, Boyle County, KY, Bullitt County, KY, Edmonson County, KY, Franklin County, KY, Grayson County, KY, Green County, KY, Hardin County, KY, Hart County, KY, Jefferson County, KY, Larue County, KY, Marion County, KY, Mercer County, KY, Nelson County, KY, Shelby County, KY, Spencer County, KY, Taylor County, KY, Washington County, KY, Woodford County, KY

The radar

The Louisville radar (KLVX), 43 km from the middle of the area, began a volume at 20:38 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

Nashville Metro, TN (KBNA), launched 12:00Z, 8.6 hours before the alert went out and 186 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: 593 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 594 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 179 m²/s²
0-3 km storm-relative helicity: 160 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 3.2

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
Apr 7, 11:51 AM EDT	Mesoscale Discussion	SPC	Union	54 min
Apr 7, 2:14 PM EDT	Mesoscale Discussion	SPC	Crittenden, Daviess, Hancock, Henderson, McLean, Union and 1 more	61 min
Apr 7, 2:37 PM EDT	Severe Thunderstorm Watch	SPC	Anderson, Bourbon, Boyle, Breckinridge, Bullitt, Butler and 41 more	5 hr
Apr 7, 3:53 PM EDT	Mesoscale Discussion	SPC	Ballard, Breckinridge, Bullitt, Butler, Caldwell, Christian and 21 more	97 min
Apr 7, 6:34 PM EDT	Mesoscale Discussion	SPC	Bath, Bourbon, Boyle, Breathitt, Carter, Casey and 35 more	56 min
Apr 7, 6:58 PM EDT	Severe Thunderstorm Watch	SPC	Bath, Breathitt, Clay, Elliott, Estill, Floyd and 17 more	2 hr

Nearby

Mesoscale Discussions in Kentucky, 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.