Alert archive / Illinois / Mesoscale Discussions in 2015

Mesoscale Discussion 197

April 3, 20159 counties in Illinois; 4 counties in Kentucky; Scott County, Missouri

The Storm Prediction Center issued this mesoscale discussion at Apr 3, 2015, 3:39 AM CDT for 9 counties in Illinois; 4 counties in Kentucky; Scott County, Missouri. It was in force for 66 min.

The area

The outline as issued.

The facts

Issued: Apr 3, 2015, 3:39 AM CDT (08:39 UTC)
Expired: Apr 3, 2015, 4:45 AM CDT
In force: 66 min
Issued by: the Storm Prediction Center

Counties Alexander County, IL, Gallatin County, IL, Hardin County, IL, Johnson County, IL, Massac County, IL, Pope County, IL, Pulaski County, IL, Saline County, IL, Union County, IL, Ballard County, KY, Carlisle County, KY, Livingston County, KY, McCracken County, KY, Scott County, MO

The radar

The Paducah radar (KPAH), 26 km from the middle of the area, began a volume at 08:40 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, 8.7 hours before the alert went out and 243 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: 262 J/kg
Mixed-layer CIN: -46 J/kg
Mixed-layer LCL: 1208 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 237 m²/s²
0-3 km storm-relative helicity: 379 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 4.5

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 2, 7:32 PM CDT	Mesoscale Discussion	SPC	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 17 more	58 min
Apr 2, 10:41 PM CDT	Severe Thunderstorm Watch	SPC	Alexander, Clinton, Edwards, Franklin, Gallatin, Hamilton and 19 more	6 hr
Apr 3, 11:56 AM CDT	Mesoscale Discussion	SPC	Gallatin, Hardin, Johnson, Massac, Pope, Pulaski and 1 more	94 min
Apr 3, 12:14 PM CDT	Tornado Watch	SPC	Gallatin, Hardin, Johnson, Massac, Pope, Pulaski and 1 more	8 hr
Apr 3, 2:23 PM CDT	Mesoscale Discussion	SPC	Adair, Allen, Anderson, Barren, Bath, Bell and 96 more	97 min
Apr 3, 3:10 PM CDT	Tornado Watch	SPC	Adair, Anderson, Bath, Bell, Bourbon, Boyle and 53 more	6 hr
Apr 3, 5:10 PM CDT	Mesoscale Discussion	SPC	Boyd, Greenup	95 min
Apr 2, 7:02 PM CDT	Tornado Watch	SPC	Barry, Barton, Cedar, Christian, Dade, Dallas and 21 more	8 hr
Apr 2, 10:12 PM CDT	Mesoscale Discussion	SPC	Barry, Christian, Douglas, Lawrence, McDonald, Newton and 3 more	93 min
Apr 3, 1:16 AM CDT	Mesoscale Discussion	SPC	Barry, Barton, Butler, Carter, Cedar, Christian and 23 more	59 min
Apr 3, 1:35 AM CDT	Tornado Watch	SPC	Butler, Carter, Dunklin, Mississippi, New Madrid, Pemiscot and 2 more	6 hr
Apr 3, 1:52 AM CDT	Severe Thunderstorm Watch	SPC	Barry, Barton, Camden, Cedar, Christian, Dade and 24 more	4 hr
Apr 3, 4:37 AM CDT	Mesoscale Discussion	SPC	Christian, Dent, Douglas, Howell, Laclede, Oregon and 8 more	83 min
Apr 3, 5:43 AM CDT	Mesoscale Discussion	SPC	Dunklin, Pemiscot	2 hr

Nearby

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