Alert archive / Illinois / Mesoscale Discussions in 2011

Mesoscale Discussion 158

February 27, 20114 states

The Storm Prediction Center issued this mesoscale discussion at Feb 27, 2011, 8:25 PM CST for 4 states. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued
Feb 27, 2011, 8:25 PM CST (02:25 UTC)
Expired
Feb 27, 2011, 9:30 PM CST
In force
65 min
Issued by
the Storm Prediction Center
All 93 counties

Alexander County, IL, Bond County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Douglas County, IL, Edgar County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jasper County, IL, Jefferson County, IL, Jersey County, IL, Johnson County, IL, Lawrence County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Massac County, IL, Monroe County, IL, Montgomery County, IL, Moultrie County, IL, Perry County, IL, Pope County, IL, Pulaski County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Shelby County, IL, Union County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Boone County, IN, Brown County, IN, Clay County, IN, Clinton County, IN, Daviess County, IN, Dubois County, IN, Fountain County, IN, Gibson County, IN, Greene County, IN, Hamilton County, IN, Hendricks County, IN, Johnson County, IN, Knox County, IN, Lawrence County, IN, Marion County, IN, Martin County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Orange County, IN, Owen County, IN, Parke County, IN, Pike County, IN, Posey County, IN, Putnam County, IN, Sullivan County, IN, Tipton County, IN, Vanderburgh County, IN, Vermillion County, IN, Vigo County, IN, Warrick County, IN, Ballard County, KY, Crittenden County, KY, Henderson County, KY, Livingston County, KY, McCracken County, KY, Union County, KY, Bollinger County, MO, Cape Girardeau County, MO, City of Saint Louis, MO, Jefferson County, MO, Madison County, MO, Perry County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Scott County, MO

The radar

The Evansville,IN radar (KVWX), 57 km from the middle of the area, began a volume at 02:27 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

Lincoln, IL (KILX), launched 00:00Z, 2.4 hours before the alert went out and 169 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, Lincoln, IL at 00:00Z on 2011-02-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 124 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, Lincoln, IL at 00:00Z on 2011-02-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 89 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
124 J/kg
Mixed-layer CIN
-220 J/kg
Mixed-layer LCL
494 m above ground
0-6 km bulk shear
76 kt
0-1 km storm-relative helicity
89 m²/s²
0-3 km storm-relative helicity
210 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

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.

IssuedProductOfficeCountiesLasted
Feb 27, 8:49 PM CSTMesoscale DiscussionSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 10 more6 hr
Feb 27, 9:40 PM CSTTornado WatchSPCAlexander, Bond, Calhoun, Clinton, Edwards, Fayette and 27 more6 hr
Feb 27, 10:41 PM CSTMesoscale DiscussionSPCBond, Clinton, Franklin, Jackson, Jefferson, Jersey and 9 more94 min
Feb 27, 11:46 PM CSTTornado WatchSPCClark, Clay, Crawford, Cumberland, Effingham, Jasper and 2 more5 hr
Feb 28, 1:05 AM CSTMesoscale DiscussionSPCAlexander, Gallatin, Hardin, Massac, Pope, Pulaski25 min
Feb 28, 12:28 AM CSTMesoscale DiscussionSPCDearborn, Fayette, Franklin, Ohio, Ripley, Switzerland and 2 more32 min
Feb 28, 12:40 AM CSTTornado WatchSPCDearborn, Fayette, Franklin, Ohio, Ripley, Switzerland and 2 more6 hr
Feb 28, 1:33 AM CSTTornado WatchSPCClark, Crawford, Dubois, Floyd, Harrison, Jefferson and 4 more7 hr
Feb 28, 2:32 AM CSTMesoscale DiscussionSPCBartholomew, Brown, Dearborn, Decatur, Fayette, Franklin and 14 more58 min
Feb 28, 3:25 AM CSTMesoscale DiscussionSPCClark, Floyd, Harrison, Perry65 min
Feb 28, 4:31 AM CSTMesoscale DiscussionSPCBath, Boyd, Breathitt, Carter, Clay, Elliott and 31 more29 min
Feb 28, 4:47 AM CSTTornado WatchSPCBath, Bell, Boyd, Breathitt, Carter, Clay and 31 more5 hr
Feb 27, 7:03 PM CSTMesoscale DiscussionSPCBarton, Camden, Cedar, Christian, Dade, Dallas and 17 more87 min
Feb 27, 7:24 PM CSTTornado WatchSPCBarry, Barton, Benton, Camden, Cedar, Christian and 28 more7 hr

Nearby

Mesoscale Discussions in Illinois, 2011Mesoscale Discussions in Indiana, 2011Mesoscale Discussions in Missouri, 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.