Alert archive / Illinois / Mesoscale Discussions in 2011

Mesoscale Discussion 847

May 22, 20115 states

The Storm Prediction Center issued this mesoscale discussion at May 22, 2011, 4:41 AM CDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
May 22, 2011, 4:41 AM CDT (09:41 UTC)
Expired
May 22, 2011, 6:45 AM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 135 counties

Allamakee County, IA, Appanoose County, IA, Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Cedar County, IA, Clayton County, IA, Clinton County, IA, Davis County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Fayette County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Mahaska County, IA, Monroe County, IA, Muscatine County, IA, Poweshiek County, IA, Scott County, IA, Tama County, IA, Van Buren County, IA, Wapello County, IA, Washington County, IA, Winneshiek County, IA, Adams County, IL, Boone County, IL, Brown County, IL, Bureau County, IL, Carroll County, IL, Cass County, IL, DeKalb County, IL, DuPage County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Jo Daviess County, IL, Kane County, IL, Kendall County, IL, Knox County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McHenry County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Morgan County, IL, Ogle County, IL, Peoria County, IL, Pike County, IL, Putnam County, IL, Rock Island County, IL, Schuyler County, IL, Scott County, IL, Stark County, IL, Stephenson County, IL, Tazewell County, IL, Warren County, IL, Whiteside County, IL, Winnebago County, IL, Woodford County, IL, Fillmore County, MN, Houston County, MN, Wabasha County, MN, Winona County, MN, Adair County, MO, Audrain County, MO, Boone County, MO, Clark County, MO, Knox County, MO, Lewis County, MO, Macon County, MO, Marion County, MO, Monroe County, MO, Pike County, MO, Ralls County, MO, Randolph County, MO, Schuyler County, MO, Scotland County, MO, Shelby County, MO, Adams County, WI, Buffalo County, WI, Chippewa County, WI, Clark County, WI, Columbia County, WI, Crawford County, WI, Dane County, WI, Dodge County, WI, Dunn County, WI, Eau Claire County, WI, Fond du Lac County, WI, Grant County, WI, Green County, WI, Green Lake County, WI, Iowa County, WI, Jackson County, WI, Jefferson County, WI, Juneau County, WI, La Crosse County, WI, Lafayette County, WI, Marathon County, WI, Marquette County, WI, Milwaukee County, WI, Monroe County, WI, Pepin County, WI, Pierce County, WI, Portage County, WI, Richland County, WI, Rock County, WI, Sauk County, WI, Trempealeau County, WI, Vernon County, WI, Walworth County, WI, Washington County, WI, Waukesha County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI, Wood County, WI

The radar

The La Crosse radar (KARX), 94 km from the middle of the area, began a volume at 09:44 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

Davenport, (KDVN), launched 00:00Z, 9.7 hours before the alert went out and 159 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 00:00Z on 2011-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 553 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 00:00Z on 2011-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 70 square meters per square second.1939587897117Sfc1 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
553 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
1729 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
59 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.

807 
ACUS11 KWNS 220941
SWOMCD
SPC MCD 220941 
ILZ000-WIZ000-IAZ000-MOZ000-MNZ000-221145-

MESOSCALE DISCUSSION 0847
NWS STORM PREDICTION CENTER NORMAN OK
0441 AM CDT SUN MAY 22 2011

AREAS AFFECTED...NORTHEAST MO/EASTERN IA/SOUTHEAST MN AND
NORTHERN/WESTERN IL AND WESTERN/SOUTHERN WI

CONCERNING...OUTLOOK UPGRADE 

VALID 220941Z - 221145Z

AN UPGRADE TO A CATEGORICAL MODERATE RISK IS ANTICIPATED WITH THE
DAY 1 OUTLOOK UPDATE AT 13Z. THIS WILL LIKELY INCLUDE PORTIONS OF
NORTHEAST MO/EASTERN IA/SOUTHEAST MN INTO WESTERN/NORTHERN IL AND
WESTERN/SOUTHERN WI...WITH THE PRIMARY SEVERE THREAT EXPECTED LATER
THIS AFTERNOON/EVENING. FOR ADDITIONAL METEOROLOGICAL
DISCUSSION...SEE THE DAY 1 OUTLOOK THAT WILL BE ISSUED BY AROUND
13Z. A PUBLIC SEVERE WEATHER OUTLOOK /PWO/ WILL ALSO BE ISSUED EARLY
THIS MORNING.

..GUYER.. 05/22/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...GRB...LOT...ILX...MKX...LSX...DVN...ARX...MPX...
DMX...EAX...

LAT...LON   44959250 45429167 44978922 43198781 40468827 38749248
            40919309 43249219 44959250

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 22, 10:53 AM CDTMesoscale DiscussionSPCAdams, Carroll, Hancock, Henderson, Henry, Jo Daviess and 7 more2 hr
May 22, 12:51 PM CDTTornado WatchSPCAdams, Bond, Brown, Bureau, Calhoun, Carroll and 42 more10 hr
May 22, 1:49 PM CDTMesoscale DiscussionSPCBoone, Cook, DeKalb, DuPage, Grundy, Kane and 10 more56 min
May 22, 2:04 PM CDTTornado WatchSPCBoone, Cook, DeKalb, DuPage, Ford, Grundy and 12 more9 hr
May 22, 2:59 PM CDTMesoscale DiscussionSPCJo Daviess2 hr
May 22, 4:16 PM CDTMesoscale DiscussionSPCChampaign, Douglas, Edgar, Ford, Iroquois, Kankakee and 2 more119 min
May 22, 5:47 PM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, DeKalb, DuPage, Grundy and 23 more88 min
May 21, 8:55 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Black Hawk, Boone and 68 more65 min
May 22, 12:07 PM CDTTornado WatchSPCAllamakee, Chickasaw, Clayton, Fayette, Floyd, Howard and 2 more7 hr
May 22, 3:43 PM CDTTornado WatchSPCPine5 hr
May 21, 7:18 PM CDTMesoscale DiscussionSPCAndrew, Buchanan, Caldwell, Carroll, Chariton, Clay and 23 more57 min
May 22, 5:18 AM CDTMesoscale DiscussionSPCDunklin, Pemiscot57 min
May 22, 1:06 PM CDTMesoscale DiscussionSPCBarry, Barton, Benton, Camden, Cedar, Christian and 24 more114 min
May 22, 1:27 PM CDTTornado WatchSPCBarry, Barton, Benton, Camden, Cedar, Christian and 23 more8 hr
May 22, 3:48 PM CDTMesoscale DiscussionSPCBarry, Barton, Bates, Benton, Camden, Cedar and 27 more117 min
May 22, 6:10 PM CDTMesoscale DiscussionSPCBarry, Barton, Bates, Benton, Camden, Cedar and 27 more65 min

Nearby

Mesoscale Discussions in Illinois, 2011Mesoscale Discussions in Wisconsin, 2011Mesoscale Discussions in Iowa, 2011Every mesoscale discussion in 2011

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.