Alert archive / Illinois / Mesoscale Discussions in 2007

Mesoscale Discussion 417

April 3, 200725 counties in Illinois; 9 counties in Iowa; 9 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Apr 3, 2007, 4:05 AM CDT for 25 counties in Illinois; 9 counties in Iowa; 9 counties in Missouri. It was in force for 55 min.

The area

The outline as issued.

The facts

Issued: Apr 3, 2007, 4:05 AM CDT (09:05 UTC)
Expired: Apr 3, 2007, 5:00 AM CDT
In force: 55 min
Issued by: the Storm Prediction Center

All 43 counties

Des Moines County, IA, Henry County, IA, Jefferson County, IA, Keokuk County, IA, Lee County, IA, Louisa County, IA, Muscatine County, IA, Van Buren County, IA, Washington County, IA, Adams County, IL, Brown County, IL, Bureau County, IL, Cass County, IL, Fulton County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Knox County, IL, LaSalle County, IL, Livingston County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Mercer County, IL, Peoria County, IL, Pike County, IL, Putnam County, IL, Rock Island County, IL, Schuyler County, IL, Stark County, IL, Tazewell County, IL, Warren County, IL, Woodford County, IL, Adair County, MO, Clark County, MO, Knox County, MO, Lewis County, MO, Macon County, MO, Marion County, MO, Ralls County, MO, Scotland County, MO, Shelby County, MO

The radar

The Quad Cities radar (KDVN), 116 km from the middle of the area, began a volume at 09:07 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 108Apr 3, 4:20 AM CDT

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 9.1 hours before the alert went out and 121 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: 1600 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 178 m²/s²
0-3 km storm-relative helicity: 318 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 2, 9:22 PM CDT	Severe Thunderstorm Watch	SPC	Carroll, Jo Daviess, Rock Island, Stephenson, Whiteside	8 hr
Apr 2, 11:33 PM CDT	Mesoscale Discussion	SPC	Carroll, Jo Daviess, Ogle, Stephenson, Winnebago	57 min
Apr 3, 1:27 AM CDT	Mesoscale Discussion	SPC	Carroll, Jo Daviess, Rock Island, Stephenson, Whiteside	93 min
Apr 3, 4:19 AM CDT	Severe Thunderstorm Watch	SPC	Adams, Brown, Bureau, Fulton, Hancock, Henderson and 16 more	6 hr
Apr 3, 7:17 AM CDT	Mesoscale Discussion	SPC	Adams, Brown, Calhoun, Cass, Fulton, Greene and 15 more	88 min
Apr 3, 9:08 AM CDT	Mesoscale Discussion	SPC	Bond, Champaign, Christian, Clark, Clay, Clinton and 26 more	67 min
Apr 3, 9:46 AM CDT	Mesoscale Discussion	SPC	Bond, Calhoun, Christian, Clark, Clay, Clinton and 37 more	29 min
Apr 3, 9:48 AM CDT	Severe Thunderstorm Watch	SPC	Bond, Calhoun, Cass, Champaign, Christian, Clark and 32 more	6 hr
Apr 3, 11:04 AM CDT	Mesoscale Discussion	SPC	Alexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 11 more	26 min
Apr 3, 11:51 AM CDT	Tornado Watch	SPC	Alexander, Bond, Clark, Clay, Clinton, Crawford and 30 more	8 hr
Apr 3, 2:25 PM CDT	Mesoscale Discussion	SPC	Alexander, Bond, Clay, Clinton, Crawford, Edwards and 26 more	65 min
Apr 2, 8:05 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Audubon, Benton, Black Hawk and 86 more	115 min
Apr 2, 11:40 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Audubon, Cass, Clarke, Decatur and 11 more	65 min
Apr 3, 12:03 AM CDT	Severe Thunderstorm Watch	SPC	Adair, Adams, Appanoose, Audubon, Cass, Clarke and 24 more	7 hr
Apr 3, 2:22 AM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Audubon, Cass, Clarke and 24 more	53 min
Apr 3, 4:28 AM CDT	Mesoscale Discussion	SPC	Carroll, Cass, Chariton, Clay, Cole, Cooper and 12 more	62 min
Apr 3, 7:37 AM CDT	Severe Thunderstorm Watch	SPC	Audrain, Bates, Benton, Boone, Callaway, Camden and 30 more	8 hr
Apr 3, 2:17 PM CDT	Mesoscale Discussion	SPC	Dunklin, Pemiscot	118 min
Apr 3, 3:12 PM CDT	Tornado Watch	SPC	Dunklin, Pemiscot	7 hr

Nearby

Mesoscale Discussions in Illinois, 2007 Mesoscale Discussions in Iowa, 2007 Mesoscale Discussions in Missouri, 2007 Every mesoscale discussion in 2007

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.