Alert archive / Illinois / Mesoscale Discussions in 2017

Mesoscale Discussion 225

February 28, 201743 counties in Illinois; Des Moines County, Lee County, Iowa; Clark County, Lewis County, Missouri

The Storm Prediction Center issued this mesoscale discussion at Feb 28, 2017, 8:06 PM CST for 43 counties in Illinois; Des Moines County, Lee County, Iowa; Clark County, Lewis County, Missouri. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued
Feb 28, 2017, 8:06 PM CST (02:06 UTC)
Expired
Feb 28, 2017, 9:30 PM CST
In force
84 min
Issued by
the Storm Prediction Center
All 47 counties

Des Moines County, IA, Lee County, IA, Adams County, IL, Brown County, IL, Bureau County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, DeWitt County, IL, Douglas County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Iroquois County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, LaSalle County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Morgan County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Putnam County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Stark County, IL, Tazewell County, IL, Vermilion County, IL, Warren County, IL, Will County, IL, Woodford County, IL, Clark County, MO, Lewis County, MO

The radar

The Lincoln radar (KILX), 54 km from the middle of the area, began a volume at 02:09 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, 2.1 hours before the alert went out and 114 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 2017-03-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 687 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 2017-03-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 395 square meters per square second.1939587897117136Sfc1 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
687 J/kg
Mixed-layer CIN
-73 J/kg
Mixed-layer LCL
887 m above ground
0-6 km bulk shear
72 kt
0-1 km storm-relative helicity
395 m²/s²
0-3 km storm-relative helicity
431 m²/s²
Significant tornado parameter
1.6
Supercell composite
6.7

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 28, 7:46 PM CSTMesoscale DiscussionSPCAlexander, Clay, Crawford, Edwards, Franklin, Gallatin and 21 more119 min
Feb 28, 8:29 PM CSTTornado WatchSPCAlexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more12 hr
Feb 28, 9:04 PM CSTTornado WatchSPCAdams, Bond, Brown, Calhoun, Clinton, Fayette and 11 more7 hr
Feb 28, 9:51 PM CSTTornado WatchSPCCass, Champaign, Christian, Clark, Clay, Coles and 37 more6 hr
Feb 28, 10:09 PM CSTMesoscale DiscussionSPCEdwards, Franklin, Gallatin, Hamilton, Jackson, Johnson and 5 more66 min
Feb 28, 11:52 PM CSTMesoscale DiscussionSPCChampaign, Ford, Iroquois, Vermilion53 min
Mar 1, 2:09 AM CSTMesoscale DiscussionSPCAlexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 8 more2 hr
Mar 1, 3:03 AM CSTTornado WatchSPCAlexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more5 hr
Mar 1, 4:19 AM CSTMesoscale DiscussionSPCAlexander, Gallatin, Hardin, Johnson, Massac, Pope and 3 more56 min
Feb 28, 6:05 PM CSTMesoscale DiscussionSPCAdair, Audrain, Barton, Bates, Benton, Boone and 39 more115 min
Feb 28, 6:23 PM CSTTornado WatchSPCAdair, Bates, Carroll, Cass, Chariton, Cooper and 15 more5 hr
Feb 28, 10:01 PM CSTMesoscale DiscussionSPCBarry, Barton, Bates, Benton, Camden, Cedar and 14 more119 min
Mar 1, 12:16 AM CSTMesoscale DiscussionSPCBarton, Camden, Cedar, Christian, Cole, Crawford and 28 more89 min

Nearby

Mesoscale Discussions in Illinois, 2017Mesoscale Discussions in Iowa, 2017Mesoscale Discussions in Missouri, 2017Every mesoscale discussion in 2017

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.