Alert archive / Illinois / Severe Thunderstorm Watches in 2015

Severe Thunderstorm Watch 429

July 16, 201540 counties in Illinois; 5 counties in Iowa; 17 counties in Missouri

The Storm Prediction Center issued this severe thunderstorm watch at Jul 16, 2015, 4:55 PM CDT for 40 counties in Illinois; 5 counties in Iowa; 17 counties in Missouri. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Jul 16, 2015, 4:55 PM CDT (21:55 UTC)
Expired
Jul 17, 2015, 12:00 AM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 62 counties

Des Moines County, IA, Henry County, IA, Lee County, IA, Louisa County, IA, Van Buren County, IA, Adams County, IL, Brown County, IL, Bureau County, IL, Cass County, IL, Champaign County, IL, DeWitt 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, 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, Adair County, MO, Audrain County, MO, Chariton County, MO, Clark County, MO, Knox County, MO, Lewis County, MO, Linn 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, Sullivan County, MO

The radar

The Lincoln radar (KILX), 111 km from the middle of the area, began a volume at 21:56 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
2%
Ten or more severe wind reports
30%
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
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 16, 5:13 PM CDTSevere Thunderstorm WarningDVNHenry32 min
Jul 16, 5:26 PM CDTSevere Thunderstorm WarningEAXAdair, Macon34 min
Jul 16, 5:32 PM CDTSevere Thunderstorm WarningDVNHenderson43 min
Jul 16, 5:34 PM CDTSevere Thunderstorm WarningDVNDes Moines, Louisa41 min
Jul 16, 5:43 PM CDTSevere Thunderstorm WarningEAXAdair, Macon32 min
Jul 16, 5:45 PM CDTTornado WarningDVNHenderson45 min
Jul 16, 5:49 PM CDTSevere Thunderstorm WarningLSXKnox, Lewis41 min
Jul 16, 6:17 PM CDTSevere Thunderstorm WarningDVNHenderson, Mercer, Warren43 min
Jul 16, 6:22 PM CDTSevere Thunderstorm WarningLSXKnox, Lewis, Shelby38 min
Jul 16, 6:25 PM CDTSevere Thunderstorm WarningLSXKnox, Lewis50 min
Jul 16, 6:35 PM CDTTornado WarningDVNHenderson, Warren55 min
Jul 16, 6:58 PM CDTSevere Thunderstorm WarningLSXKnox, Lewis, Marion, Shelby47 min
Jul 16, 7:01 PM CDTSevere Thunderstorm WarningLSXAdams25 min
Jul 16, 7:05 PM CDTTornado Warning Tornado observedDVNWarren40 min
Jul 16, 7:25 PM CDTTornado Warning Tornado observedILXKnox50 min
Jul 16, 7:42 PM CDTSevere Thunderstorm WarningDVNMcDonough, Warren26 min
Jul 16, 7:44 PM CDTTornado WarningDVNWarren20 min
Jul 16, 7:49 PM CDTFlash Flood WarningDVNWarren4 hr
Jul 16, 7:49 PM CDTSevere Thunderstorm WarningILXFulton, Knox41 min
Jul 16, 8:04 PM CDTFlash Flood WarningILXKnox6 hr
Jul 16, 8:05 PM CDTFlash Flood WarningDVNHenry, Rock Island, Whiteside3 hr
Jul 16, 8:27 PM CDTSevere Thunderstorm WarningILXPeoria48 min
Jul 16, 8:48 PM CDTFlash Flood WarningILXPeoria6 hr
Jul 16, 9:00 PM CDTTornado WarningILXFulton, Peoria30 min
Jul 16, 9:02 PM CDTTornado WarningILXFulton28 min
Jul 16, 9:23 PM CDTSevere Thunderstorm WarningILXMarshall, Tazewell, Woodford52 min
Jul 16, 9:34 PM CDTSevere Thunderstorm WarningILXLogan, Mason, Tazewell41 min
Jul 16, 11:40 PM CDTFlash Flood WarningILXTazewell6 hr

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, 9.9 hours before the alert went out and 123 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 12:00Z on 2015-07-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 2015-07-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1260 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
229 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.

IssuedProductOfficeCountiesLasted
Jul 16, 3:41 PM CDTMesoscale DiscussionSPCFulton, Hancock, Henderson, Henry, Knox, McDonough and 8 more2 hr
Jul 15, 9:22 PM CDTMesoscale DiscussionSPCAdair, Adams, Cass, Clarke, Decatur, Fremont and 9 more113 min
Jul 16, 6:44 PM CDTMesoscale DiscussionSPCAudubon, Carroll, Cass, Crawford, Harrison, Ida and 6 more3 hr

Nearby

Severe Thunderstorm Watches in Illinois, 2015Severe Thunderstorm Watches in Missouri, 2015Severe Thunderstorm Watches in Iowa, 2015Every severe thunderstorm watch in 2015

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.