Alert archive / Missouri / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 582

August 16, 201242 counties in Illinois; 55 counties in Missouri

The Storm Prediction Center issued this severe thunderstorm watch at Aug 16, 2012, 1:05 PM CDT for 42 counties in Illinois; 55 counties in Missouri. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Aug 16, 2012, 1:05 PM CDT (18:05 UTC)
Expired: Aug 16, 2012, 8:00 PM CDT
In force: 7 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 60 kt

All 97 counties

Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Cumberland County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Effingham County, IL, Fayette County, IL, Greene County, IL, Jackson County, IL, Jasper County, IL, Jefferson County, IL, Jersey County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Mason County, IL, Menard County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Perry County, IL, Piatt County, IL, Pike County, IL, Randolph County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Vermilion County, IL, Washington County, IL, Audrain County, MO, Barry County, MO, Bollinger County, MO, Butler County, MO, Callaway County, MO, Camden County, MO, Cape Girardeau County, MO, Carter County, MO, Christian County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Dallas County, MO, Dent County, MO, Douglas County, MO, Franklin County, MO, Gasconade County, MO, Greene County, MO, Howell County, MO, Iron County, MO, Jefferson County, MO, Laclede County, MO, Lawrence County, MO, Lincoln County, MO, Madison County, MO, Maries County, MO, McDonald County, MO, Miller County, MO, Montgomery County, MO, Newton County, MO, Oregon County, MO, Osage County, MO, Ozark County, MO, Perry County, MO, Phelps County, MO, Pike County, MO, Polk County, MO, Pulaski County, MO, Ralls County, MO, Reynolds County, MO, Ripley County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Shannon County, MO, Stoddard County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Warren County, MO, Washington County, MO, Wayne County, MO, Webster County, MO, Wright County, MO

The radar

The St Louis radar (KLSX), 112 km from the middle of the area, began a volume at 18:04 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: 20%
One or more EF2 to EF5 tornadoes: 5%
Ten or more severe wind reports: 30%
One or more gusts of 65 knots or more: 30%
Ten or more severe hail reports: 30%
One or more hailstones of 2 inches or more: 20%
Six or more combined severe hail and wind reports: 70%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Aug 16, 1:30 PM CDT	Severe Thunderstorm Warning	SGF	Dent, Shannon, Texas	45 min
Aug 16, 1:33 PM CDT	Severe Thunderstorm Warning	SGF	Douglas, Texas, Wright	28 min
Aug 16, 2:04 PM CDT	Severe Thunderstorm Warning	SGF	Christian, Douglas, Webster	41 min
Aug 16, 2:06 PM CDT	Severe Thunderstorm Warning	ILX	Champaign, Douglas, Edgar, Vermilion	54 min
Aug 16, 2:07 PM CDT	Severe Thunderstorm Warning	LSX	Gasconade, Osage	23 min
Aug 16, 2:07 PM CDT	Severe Thunderstorm Warning	SGF	Texas, Wright	38 min
Aug 16, 2:09 PM CDT	Severe Thunderstorm Warning	SGF	Shannon, Texas	51 min
Aug 16, 2:11 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene	39 min
Aug 16, 2:15 PM CDT	Severe Thunderstorm Warning	LSX	Franklin, Warren	30 min
Aug 16, 2:24 PM CDT	Severe Thunderstorm Warning	SGF	Dallas, Laclede	30 min
Aug 16, 2:37 PM CDT	Severe Thunderstorm Warning	LSX	Franklin	23 min
Aug 16, 2:53 PM CDT	Severe Thunderstorm Warning	PAH	Jackson	52 min
Aug 16, 2:54 PM CDT	Severe Thunderstorm Warning	LSX	Crawford, Franklin, Gasconade, Washington	51 min
Aug 16, 2:58 PM CDT	Severe Thunderstorm Warning	ILX	Christian	50 min
Aug 16, 2:58 PM CDT	Severe Thunderstorm Warning	LSX	Franklin, Jefferson	47 min
Aug 16, 2:59 PM CDT	Severe Thunderstorm Warning	SGF	Howell, Shannon, Texas	46 min
Aug 16, 3:07 PM CDT	Severe Thunderstorm Warning	PAH	Jefferson	21 min
Aug 16, 3:07 PM CDT	Severe Thunderstorm Warning	SGF	Dent, Laclede, Phelps, Pulaski, Texas, Wright	53 min
Aug 16, 3:08 PM CDT	Severe Thunderstorm Warning	LSX	Macoupin, Madison	37 min
Aug 16, 3:08 PM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Saint Louis, City of Saint Louis	52 min
Aug 16, 3:15 PM CDT	Severe Thunderstorm Warning	ILX	Christian, Coles, Cumberland, Douglas, Macon, Moultrie and 2 more	60 min
Aug 16, 3:18 PM CDT	Severe Thunderstorm Warning	LSX	Madison, Saint Clair	42 min
Aug 16, 3:21 PM CDT	Flash Flood Warning	PAH	Jackson	114 min
Aug 16, 3:28 PM CDT	Severe Thunderstorm Warning	LSX	Monroe	47 min
Aug 16, 3:28 PM CDT	Severe Thunderstorm Warning	SGF	Laclede, Texas, Webster, Wright	47 min
Aug 16, 3:29 PM CDT	Severe Thunderstorm Warning	ILX	Champaign, Edgar, Vermilion	61 min
Aug 16, 3:29 PM CDT	Severe Thunderstorm Warning	PAH	Wayne	46 min
Aug 16, 3:33 PM CDT	Severe Thunderstorm Warning	SGF	Oregon, Shannon	42 min
Aug 16, 3:37 PM CDT	Severe Thunderstorm Warning	PAH	Jackson	53 min
Aug 16, 3:41 PM CDT	Tornado Warning	ILX	Coles, Cumberland, Moultrie, Shelby	37 min
Aug 16, 3:43 PM CDT	Severe Thunderstorm Warning	LSX	Saint Clair	47 min
Aug 16, 3:43 PM CDT	Severe Thunderstorm Warning	LSX	Bond, Fayette, Montgomery	47 min
Aug 16, 3:45 PM CDT	Severe Thunderstorm Warning	ILX	Cumberland, Effingham, Jasper, Shelby	60 min
Aug 16, 3:48 PM CDT	Severe Thunderstorm Warning	PAH	Wayne	28 min
Aug 16, 3:52 PM CDT	Severe Thunderstorm Warning	LSX	Bond, Clinton, Madison	38 min
Aug 16, 3:54 PM CDT	Severe Thunderstorm Warning	LSX	Jefferson, Saint Francois, Washington	33 min
Aug 16, 3:57 PM CDT	Severe Thunderstorm Warning	ILX	Clark, Coles, Cumberland, Douglas, Edgar	63 min
Aug 16, 3:59 PM CDT	Tornado Warning	ILX	Clay, Cumberland, Effingham, Jasper	46 min
Aug 16, 4:01 PM CDT	Tornado Warning	ILX	Clark, Coles, Cumberland, Edgar	35 min
Aug 16, 4:07 PM CDT	Severe Thunderstorm Warning	LSX	Clinton, Marion	53 min
Aug 16, 4:21 PM CDT	Severe Thunderstorm Warning	LSX	Crawford, Washington	27 min
Aug 16, 4:23 PM CDT	Severe Thunderstorm Warning	PAH	Cape Girardeau, Perry	19 min
Aug 16, 4:25 PM CDT	Severe Thunderstorm Warning	LSX	Fayette	35 min
Aug 16, 4:26 PM CDT	Severe Thunderstorm Warning	LSX	Saint Clair	24 min
Aug 16, 4:26 PM CDT	Severe Thunderstorm Warning	PAH	Ripley	28 min
Aug 16, 4:29 PM CDT	Severe Thunderstorm Warning	ILX	Clay, Crawford, Jasper, Lawrence, Richland	61 min
Aug 16, 4:31 PM CDT	Severe Thunderstorm Warning	PAH	Wayne	22 min
Aug 16, 4:31 PM CDT	Severe Thunderstorm Warning	SGF	Stone, Taney	44 min
Aug 16, 4:37 PM CDT	Severe Thunderstorm Warning	SGF	Webster, Wright	38 min
Aug 16, 4:40 PM CDT	Severe Thunderstorm Warning	PAH	Butler, Ripley	50 min
Aug 16, 4:43 PM CDT	Severe Thunderstorm Warning	ILX	Cumberland, Jasper	17 min
Aug 16, 4:46 PM CDT	Severe Thunderstorm Warning	SGF	Webster	44 min
Aug 16, 4:47 PM CDT	Severe Thunderstorm Warning	SGF	Barry, Lawrence, Stone	43 min
Aug 16, 4:49 PM CDT	Severe Thunderstorm Warning	LSX	Clinton, Marion, Washington	56 min
Aug 16, 4:52 PM CDT	Severe Thunderstorm Warning	PAH	Butler, Wayne	38 min
Aug 16, 4:54 PM CDT	Severe Thunderstorm Warning	SGF	Christian, Stone, Taney	36 min
Aug 16, 5:03 PM CDT	Severe Thunderstorm Warning	SGF	Barry, Lawrence, Newton	42 min
Aug 16, 5:08 PM CDT	Severe Thunderstorm Warning	PAH	Jefferson, Perry	52 min
Aug 16, 5:16 PM CDT	Severe Thunderstorm Warning	SGF	Greene, Webster	44 min
Aug 16, 5:34 PM CDT	Severe Thunderstorm Warning	SGF	Webster	41 min
Aug 16, 5:41 PM CDT	Severe Thunderstorm Warning	SGF	Barry, Lawrence	37 min
Aug 16, 5:55 PM CDT	Severe Thunderstorm Warning	SGF	Christian, Greene, Webster	28 min
Aug 16, 6:35 PM CDT	Severe Thunderstorm Warning	SGF	Webster	40 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

Springfield, MO (KSGF), launched 12:00Z, 6.1 hours before the alert went out and 228 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: 1719 J/kg
Mixed-layer CIN: -126 J/kg
Mixed-layer LCL: 1553 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 37 m²/s²
0-3 km storm-relative helicity: 106 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
Aug 16, 3:57 AM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 19 more	3 hr
Aug 16, 10:01 AM CDT	Mesoscale Discussion	SPC	Clark, Coles, Crawford, Cumberland, Douglas, Edgar and 4 more	89 min
Aug 16, 12:47 PM CDT	Mesoscale Discussion	SPC	Bond, Calhoun, Champaign, Christian, Clark, Clay and 40 more	88 min
Aug 16, 3:07 PM CDT	Mesoscale Discussion	SPC	Clark, Clay, Coles, Crawford, Cumberland, Edwards and 8 more	83 min
Aug 16, 3:27 PM CDT	Severe Thunderstorm Watch	SPC	Alexander, Clark, Crawford, Edwards, Franklin, Gallatin and 14 more	8 hr
Aug 16, 5:25 PM CDT	Mesoscale Discussion	SPC	Alexander, Bond, Clark, Clay, Clinton, Crawford and 27 more	2 hr

Nearby

Severe Thunderstorm Watches in Missouri, 2012 Severe Thunderstorm Watches in Illinois, 2012 Every severe thunderstorm watch in 2012

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.