Alert archive / Kentucky / Mesoscale Discussions in 2015

Mesoscale Discussion 388

April 19, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2015, 8:21 PM CDT for 4 states. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued: Apr 19, 2015, 8:21 PM CDT (01:21 UTC)
Expired: Apr 19, 2015, 9:15 PM CDT
In force: 54 min
Issued by: the Storm Prediction Center
Chance of a watch: 60%

All 22 counties

Massac County, IL, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Christian County, KY, Crittenden County, KY, Fulton County, KY, Graves County, KY, Hickman County, KY, Hopkins County, KY, Livingston County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, McLean County, KY, Muhlenberg County, KY, Todd County, KY, Trigg County, KY, Mississippi County, MO, New Madrid County, MO, Lake County, TN

The radar

The Paducah radar (KPAH), 19 km from the middle of the area, began a volume at 01:22 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 00:00Z, 1.4 hours before the alert went out and 214 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: 170 J/kg
Mixed-layer CIN: -22 J/kg
Mixed-layer LCL: 927 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 41 m²/s²
0-3 km storm-relative helicity: 67 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.7

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 20, 2:36 AM CDT	Mesoscale Discussion	SPC	Clinton, Cumberland, Laurel, McCreary, Monroe, Pulaski and 3 more	84 min
Apr 19, 8:02 PM CDT	Tornado Watch	SPC	Dunklin, Pemiscot	5 hr
Apr 19, 10:16 PM CDT	Mesoscale Discussion	SPC	Dunklin, Pemiscot	59 min
Apr 20, 12:45 AM CDT	Mesoscale Discussion	SPC	Bedford, Cannon, Cheatham, Coffee, Davidson, DeKalb and 22 more	90 min
Apr 20, 1:09 AM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bedford, Bledsoe, Bradley, Campbell, Cannon and 35 more	4 hr

Nearby

Mesoscale Discussions in Kentucky, 2015 Mesoscale Discussions in Missouri, 2015 Mesoscale Discussions in Illinois, 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.