Alert archive / Illinois / Mesoscale Discussions in 2007

Mesoscale Discussion 1859

August 23, 20075 states

The Storm Prediction Center issued this mesoscale discussion at Aug 23, 2007, 10:36 AM CDT for 5 states. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued
Aug 23, 2007, 10:36 AM CDT (15:36 UTC)
Expired
Aug 23, 2007, 12:30 PM CDT
In force
114 min
Issued by
the Storm Prediction Center
All 67 counties

Cedar County, IA, Clayton County, IA, Clinton County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Henry County, IA, Jackson County, IA, Jones County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Muscatine County, IA, Scott County, IA, Boone County, IL, Bureau County, IL, Carroll County, IL, Cook County, IL, DeKalb County, IL, DuPage County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Iroquois County, IL, Jo Daviess County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Marshall County, IL, McDonough County, IL, McHenry County, IL, McLean County, IL, Mercer County, IL, Ogle County, IL, Peoria County, IL, Putnam County, IL, Rock Island County, IL, Stark County, IL, Stephenson County, IL, Tazewell County, IL, Warren County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Woodford County, IL, Lake County, IN, Clark County, MO, Dane County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Jefferson County, WI, Kenosha County, WI, Lafayette County, WI, Milwaukee County, WI, Racine County, WI, Rock County, WI, Walworth County, WI, Waukesha County, WI

The radar

The Quad Cities radar (KDVN), 67 km from the middle of the area, began a volume at 15:36 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.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 3.6 hours before the alert went out and 60 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-pSkew-T log-p diagram, Davenport, at 12:00Z on 2007-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 314 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 2007-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 223 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
314 J/kg
Mixed-layer CIN
-115 J/kg
Mixed-layer LCL
1080 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
223 m²/s²
0-3 km storm-relative helicity
200 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.2

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.

IssuedProductOfficeCountiesLasted
Aug 22, 7:21 PM CDTMesoscale DiscussionSPCBoone, Bureau, Cook, DeKalb, DuPage, Ford and 25 more2 hr
Aug 23, 12:28 PM CDTSevere Thunderstorm WatchSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 35 more7 hr
Aug 23, 3:10 PM CDTMesoscale DiscussionSPCCook, DuPage, Ford, Grundy, Iroquois, Kane and 7 more95 min
Aug 23, 5:38 PM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 25 more97 min
Aug 23, 1:48 AM CDTMesoscale DiscussionSPCDeKalb, LaGrange, Noble, Steuben, Whitley27 min
Aug 23, 2:07 PM CDTMesoscale DiscussionSPCAllen, Cass, DeKalb, Elkhart, Fulton, Huntington and 13 more83 min
Aug 23, 3:09 PM CDTSevere Thunderstorm WatchSPCAllen, DeKalb, Elkhart, Fulton, Kosciusko, LaGrange and 8 more8 hr
Aug 23, 3:57 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Benton, Black Hawk and 46 more93 min
Aug 23, 5:49 PM CDTSevere Thunderstorm WatchSPCAdams, Appanoose, Clarke, Davis, Decatur, Fremont and 13 more6 hr

Nearby

Mesoscale Discussions in Illinois, 2007Mesoscale Discussions in Iowa, 2007Mesoscale Discussions in Wisconsin, 2007Every 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.