Alert archive / Illinois / Mesoscale Discussions in 2014

Mesoscale Discussion 255

April 3, 201418 counties in Illinois

The Storm Prediction Center issued this mesoscale discussion at Apr 3, 2014, 6:24 AM CDT for 18 counties in Illinois. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: Apr 3, 2014, 6:24 AM CDT (11:24 UTC)
Expired: Apr 3, 2014, 8:00 AM CDT
In force: 96 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

Counties Bond County, IL, Clay County, IL, Clinton County, IL, Effingham County, IL, Fayette County, IL, Franklin County, IL, Hamilton County, IL, Jackson County, IL, Jasper County, IL, Jefferson County, IL, Marion County, IL, Perry County, IL, Randolph County, IL, Richland County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL

The radar

The Evansville,IN radar (KVWX), 126 km from the middle of the area, began a volume at 11:24 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

Lincoln, IL (KILX), launched 00:00Z, 11.4 hours before the alert went out and 211 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 557 m above ground
0-6 km bulk shear: 73 kt
0-1 km storm-relative helicity: 307 m²/s²
0-3 km storm-relative helicity: 511 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 3, 1:05 AM CDT	Mesoscale Discussion	SPC	Adams, Hancock, Henderson, McDonough, Mercer, Rock Island and 2 more	55 min
Apr 3, 2:49 AM CDT	Mesoscale Discussion	SPC	Adams, Bond, Brown, Bureau, Calhoun, Cass and 44 more	116 min
Apr 3, 9:22 AM CDT	Mesoscale Discussion	SPC	Hardin, Massac, Pope	83 min
Apr 3, 12:28 PM CDT	Mesoscale Discussion	SPC	Alexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 10 more	62 min
Apr 3, 12:46 PM CDT	Tornado Watch	SPC	Alexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 10 more	4 hr
Apr 3, 3:17 PM CDT	Mesoscale Discussion	SPC	Adams, Pike	58 min
Apr 3, 4:58 PM CDT	Tornado Watch	SPC	Monroe, Randolph, Saint Clair	7 hr

Nearby

Mesoscale Discussions in Illinois, 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.