Alert archive / Illinois / Severe Thunderstorm Watches in 2014

Severe Thunderstorm Watch 340

June 21, 201463 counties in Illinois; 13 counties in Missouri

The Storm Prediction Center issued this severe thunderstorm watch at Jun 21, 2014, 1:33 PM CDT for 63 counties in Illinois; 13 counties in Missouri. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Jun 21, 2014, 1:33 PM CDT (18:33 UTC)
Expired: Jun 21, 2014, 9:00 PM CDT
In force: 7 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 60 kt

All 76 counties

Adams County, IL, Boone County, IL, Brown County, IL, Bureau County, IL, Calhoun County, IL, Carroll County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Coles County, IL, Cook County, IL, DeKalb County, IL, DeWitt County, IL, Douglas County, IL, DuPage County, IL, Edgar County, IL, Ford County, IL, Fulton County, IL, Greene County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Iroquois County, IL, Jersey 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, Logan County, IL, Macon County, IL, Macoupin 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, Moultrie County, IL, Ogle County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Putnam County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Stark County, IL, Stephenson County, IL, Tazewell County, IL, Vermilion County, IL, Warren County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Woodford County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Marion County, MO, Monroe County, MO, Montgomery County, MO, Pike County, MO, Ralls County, MO, Shelby County, MO, Warren County, MO

The radar

The Quad Cities radar (KDVN), 87 km from the middle of the area, began a volume at 18:34 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes: 10%
One or more EF2 to EF5 tornadoes: 2%
Ten or more severe wind reports: 50%
One or more gusts of 65 knots or more: 10%
Ten or more severe hail reports: 30%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 80%

Warnings issued inside it

44 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Jun 21, 1:48 PM CDT	Severe Thunderstorm Warning	ILX	Fulton	42 min
Jun 21, 2:15 PM CDT	Severe Thunderstorm Warning	ILX	Fulton, Knox, Peoria	45 min
Jun 21, 2:26 PM CDT	Severe Thunderstorm Warning	ILX	Fulton	49 min
Jun 21, 2:39 PM CDT	Severe Thunderstorm Warning	ILX	Fulton, Schuyler	51 min
Jun 21, 2:42 PM CDT	Severe Thunderstorm Warning	LOT	Grundy, Iroquois, Kankakee, Livingston, Will	48 min
Jun 21, 2:49 PM CDT	Severe Thunderstorm Warning	ILX	Knox, Peoria	28 min
Jun 21, 3:09 PM CDT	Severe Thunderstorm Warning	ILX	Tazewell, Woodford	51 min
Jun 21, 3:15 PM CDT	Severe Thunderstorm Warning	ILX	Cass, Mason, Schuyler	45 min
Jun 21, 3:19 PM CDT	Severe Thunderstorm Warning	ILX	Cass, Fulton, Mason, Menard, Tazewell	41 min
Jun 21, 3:28 PM CDT	Severe Thunderstorm Warning	LOT	Iroquois, Kankakee, Livingston	62 min
Jun 21, 3:40 PM CDT	Severe Thunderstorm Warning	ILX	Logan, Mason, Tazewell	50 min
Jun 21, 4:00 PM CDT	Severe Thunderstorm Warning	ILX	Cass, Morgan	45 min
Jun 21, 4:00 PM CDT	Severe Thunderstorm Warning	LSX	Brown, Pike	30 min
Jun 21, 4:01 PM CDT	Severe Thunderstorm Warning	LSX	Adams	29 min
Jun 21, 4:09 PM CDT	Severe Thunderstorm Warning	LOT	Iroquois	49 min
Jun 21, 4:12 PM CDT	Severe Thunderstorm Warning	LSX	Monroe	48 min
Jun 21, 4:16 PM CDT	Severe Thunderstorm Warning	LSX	Brown, Pike	29 min
Jun 21, 4:17 PM CDT	Severe Thunderstorm Warning	LOT	Cook, Lake, McHenry	58 min
Jun 21, 4:23 PM CDT	Tornado Warning	LOT	Lake, McHenry	34 min
Jun 21, 4:27 PM CDT	Severe Thunderstorm Warning	LSX	Brown, Pike	48 min
Jun 21, 4:33 PM CDT	Severe Thunderstorm Warning	LSX	Callaway	25 min
Jun 21, 4:39 PM CDT	Severe Thunderstorm Warning	ILX	Morgan, Scott	51 min
Jun 21, 4:40 PM CDT	Severe Thunderstorm Warning	LOT	LaSalle, Lee	52 min
Jun 21, 4:46 PM CDT	Severe Thunderstorm Warning	LOT	Iroquois	47 min
Jun 21, 4:46 PM CDT	Severe Thunderstorm Warning	LSX	Pike	44 min
Jun 21, 4:49 PM CDT	Severe Thunderstorm Warning	DVN	Bureau	41 min
Jun 21, 4:49 PM CDT	Severe Thunderstorm Warning	LSX	Pike, Ralls	41 min
Jun 21, 4:50 PM CDT	Severe Thunderstorm Warning	LSX	Boone, Moniteau	25 min
Jun 21, 4:51 PM CDT	Tornado Warning	LOT	Iroquois	39 min
Jun 21, 4:55 PM CDT	Severe Thunderstorm Warning	LSX	Audrain	35 min
Jun 21, 5:07 PM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Kane, Lake	53 min
Jun 21, 5:07 PM CDT	Severe Thunderstorm Warning	LSX	Pike	38 min
Jun 21, 5:14 PM CDT	Severe Thunderstorm Warning	DVN	Bureau, Putnam	46 min
Jun 21, 5:27 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Pike	48 min
Jun 21, 5:29 PM CDT	Severe Thunderstorm Warning	ILX	Scott	25 min
Jun 21, 5:36 PM CDT	Flash Flood Warning	LOT	Cook, DuPage	6 hr
Jun 21, 5:44 PM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Grundy, Kane, Kendall, Will	61 min
Jun 21, 5:45 PM CDT	Severe Thunderstorm Warning	LSX	Lincoln, Montgomery, Pike, Warren	45 min
Jun 21, 6:04 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Jersey, Macoupin	41 min
Jun 21, 6:26 PM CDT	Severe Thunderstorm Warning	ILX	Vermilion	19 min
Jun 21, 6:32 PM CDT	Severe Thunderstorm Warning	LOT	Cook, Kankakee, Will	58 min
Jun 21, 6:44 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Jersey	46 min
Jun 21, 7:02 PM CDT	Flash Flood Warning	LOT	Will	6 hr
Jun 21, 7:12 PM CDT	Severe Thunderstorm Warning	LOT	Iroquois, Kankakee	53 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 6.6 hours before the alert went out and 83 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: 1411 J/kg
Mixed-layer CIN: -82 J/kg
Mixed-layer LCL: 1067 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: -32 m²/s²
0-3 km storm-relative helicity: -25 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 21, 12:41 PM CDT	Mesoscale Discussion	SPC	Adams, Boone, Brown, Bureau, Carroll, Cass and 33 more	2 hr
Jun 21, 3:41 PM CDT	Mesoscale Discussion	SPC	Adams, Boone, Brown, Bureau, Carroll, Cass and 42 more	64 min
Jun 21, 6:16 PM CDT	Mesoscale Discussion	SPC	Adams, Bond, Brown, Bureau, Calhoun, Cass and 52 more	89 min
Jun 20, 8:29 PM CDT	Mesoscale Discussion	SPC	Atchison, Holt, Nodaway	91 min
Jun 20, 8:51 PM CDT	Severe Thunderstorm Watch	SPC	Andrew, Atchison, DeKalb, Gentry, Harrison, Holt and 2 more	6 hr
Jun 20, 11:28 PM CDT	Mesoscale Discussion	SPC	Andrew, Atchison, Daviess, Gentry, Harrison, Holt and 2 more	92 min
Jun 21, 1:57 AM CDT	Mesoscale Discussion	SPC	Andrew, Atchison, DeKalb, Gentry, Harrison, Holt and 2 more	63 min

Nearby

Severe Thunderstorm Watches in Illinois, 2014 Severe Thunderstorm Watches in Missouri, 2014 Every severe thunderstorm watch in 2014

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.