Alert archive / Indiana / Tornado Watches in 2013

Tornado Watch 123

April 18, 20134 states

The Storm Prediction Center issued this tornado watch at Apr 18, 2013, 8:31 AM CDT for 4 states. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Apr 18, 2013, 8:31 AM CDT (13:31 UTC)
Expired: Apr 18, 2013, 3:35 PM CDT
In force: 7 hr
Issued by: the Storm Prediction Center
Particularly dangerous situation: Yes
Largest hail expected: 2 in
Strongest gust expected: 70 kt

All 93 counties

Clark County, IL, Clay County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Douglas County, IL, Edgar County, IL, Effingham County, IL, Jasper County, IL, Lawrence County, IL, Richland County, IL, Vermilion County, IL, Adams County, IN, Allen County, IN, Bartholomew County, IN, Benton County, IN, Blackford County, IN, Boone County, IN, Brown County, IN, Carroll County, IN, Cass County, IN, Clay County, IN, Clinton County, IN, Daviess County, IN, Decatur County, IN, DeKalb County, IN, Delaware County, IN, Elkhart County, IN, Fountain County, IN, Fulton County, IN, Grant County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Henry County, IN, Howard County, IN, Huntington County, IN, Jackson County, IN, Jasper County, IN, Jay County, IN, Jennings County, IN, Johnson County, IN, Knox County, IN, Kosciusko County, IN, LaGrange County, IN, Lake County, IN, LaPorte County, IN, Lawrence County, IN, Madison County, IN, Marion County, IN, Marshall County, IN, Martin County, IN, Miami County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Newton County, IN, Noble County, IN, Owen County, IN, Parke County, IN, Porter County, IN, Pulaski County, IN, Putnam County, IN, Randolph County, IN, Rush County, IN, Saint Joseph County, IN, Shelby County, IN, Starke County, IN, Steuben County, IN, Sullivan County, IN, Tippecanoe County, IN, Tipton County, IN, Vermillion County, IN, Vigo County, IN, Wabash County, IN, Warren County, IN, Wells County, IN, White County, IN, Whitley County, IN, Berrien County, MI, Branch County, MI, Cass County, MI, Hillsdale County, MI, Saint Joseph County, MI, Allen County, OH, Defiance County, OH, Fulton County, OH, Henry County, OH, Paulding County, OH, Putnam County, OH, Van Wert County, OH, Williams County, OH

The radar

The Northern Indiana radar (KIWX), 99 km from the middle of the area, began a volume at 13:33 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: 70%
One or more EF2 to EF5 tornadoes: 60%
Ten or more severe wind reports: 70%
One or more gusts of 65 knots or more: 40%
Ten or more severe hail reports: 20%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 95%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Apr 18, 8:57 AM CDT	Severe Thunderstorm Warning	ILX	Edgar, Vermilion	63 min
Apr 18, 9:05 AM CDT	Severe Thunderstorm Warning	IWX	LaPorte, Starke	40 min
Apr 18, 9:12 AM CDT	Severe Thunderstorm Warning	IND	Fountain, Vermillion, Warren	63 min
Apr 18, 9:17 AM CDT	Severe Thunderstorm Warning	IWX	Cass, Pulaski, White	43 min
Apr 18, 9:31 AM CDT	Severe Thunderstorm Warning	IND	Fountain, Parke, Vermillion	44 min
Apr 18, 9:37 AM CDT	Severe Thunderstorm Warning	IWX	Berrien, Cass	23 min
Apr 18, 9:38 AM CDT	Severe Thunderstorm Warning	IWX	Fulton, Marshall, Pulaski, Saint Joseph, Starke	52 min
Apr 18, 12:00 PM CDT	Flash Flood Warning	LOT	Lake	8 hr
Apr 18, 1:29 PM CDT	Severe Thunderstorm Warning	ILX	Clay, Cumberland, Effingham, Jasper	31 min
Apr 18, 2:18 PM CDT	Flash Flood Warning	ILX	Champaign, Coles, Cumberland, Douglas, Effingham, Moultrie and 2 more	18 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

Lincoln, IL (KILX), launched 12:00Z, 1.5 hours before the alert went out and 189 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 474 m above ground
0-6 km bulk shear: 58 kt
0-1 km storm-relative helicity: -203 m²/s²
0-3 km storm-relative helicity: -478 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.2

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 17, 8:21 PM CDT	Mesoscale Discussion	SPC	Cass, Champaign, Christian, Coles, DeWitt, Douglas and 21 more	84 min
Apr 17, 8:53 PM CDT	Mesoscale Discussion	SPC	Calhoun, Greene, Jersey, Pike, Scott	97 min
Apr 17, 9:57 PM CDT	Tornado Watch	SPC	Adams, Brown, Pike	7 hr
Apr 17, 10:48 PM CDT	Mesoscale Discussion	SPC	Champaign, Christian, Coles, DeWitt, Douglas, Edgar and 12 more	57 min
Apr 17, 11:46 PM CDT	Mesoscale Discussion	SPC	Calhoun, Greene, Morgan, Pike, Scott	89 min
Apr 18, 2:01 AM CDT	Mesoscale Discussion	SPC	Calhoun, Jersey	89 min
Apr 18, 4:02 AM CDT	Mesoscale Discussion	SPC	Calhoun, Greene, Jersey, Monroe	58 min
Apr 18, 5:36 AM CDT	Mesoscale Discussion	SPC	Bond, Clinton, Fayette, Madison, Monroe, Montgomery and 3 more	54 min
Apr 18, 5:42 AM CDT	Tornado Watch	SPC	Bond, Clinton, Fayette, Jersey, Macoupin, Madison and 6 more	8 hr
Apr 18, 7:25 AM CDT	Mesoscale Discussion	SPC	Champaign, Clark, Clay, Coles, Crawford, Cumberland and 17 more	95 min
Apr 18, 9:25 AM CDT	Tornado Watch	SPC	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more	8 hr
Apr 18, 11:14 AM CDT	Mesoscale Discussion	SPC	Clark, Clay, Crawford, Jasper, Lawrence, Marion and 4 more	2 hr
Apr 18, 12:48 PM CDT	Mesoscale Discussion	SPC	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more	87 min
Apr 18, 2:47 PM CDT	Mesoscale Discussion	SPC	Clark, Crawford, Lawrence	88 min
Apr 18, 3:32 PM CDT	Tornado Watch	SPC	Adams, Bartholomew, Blackford, Boone, Brown, Clay and 27 more	3 hr
Apr 18, 5:33 PM CDT	Mesoscale Discussion	SPC	Adams, Allen, Bartholomew, Blackford, Boone, Brown and 43 more	117 min
Apr 18, 8:48 AM CDT	Mesoscale Discussion	SPC	Allegan, Barry, Bay, Calhoun, Clinton, Eaton and 29 more	27 min
Apr 18, 9:06 AM CDT	Tornado Watch	SPC	Allegan, Barry, Bay, Calhoun, Clinton, Eaton and 30 more	6 hr

Nearby

Tornado Watches in Indiana, 2013 Tornado Watches in Illinois, 2013 Tornado Watches in Ohio, 2013 Every tornado watch in 2013

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.