Alert archive / Illinois / Tornado Watches in 2009

Tornado Watch 294

May 13, 200930 counties in Illinois; 9 counties in Indiana; 8 counties in Missouri

The Storm Prediction Center issued this tornado watch at May 13, 2009, 3:00 PM CDT for 30 counties in Illinois; 9 counties in Indiana; 8 counties in Missouri. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
May 13, 2009, 3:00 PM CDT (20:00 UTC)
Expired
May 13, 2009, 7:55 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 47 counties

Bond County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Crawford County, IL, Cumberland County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Jackson County, IL, Jasper County, IL, Jefferson County, IL, Johnson County, IL, Lawrence County, IL, Marion County, IL, Monroe County, IL, Perry County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Union County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Daviess County, IN, Gibson County, IN, Greene County, IN, Knox County, IN, Pike County, IN, Posey County, IN, Sullivan County, IN, Vanderburgh County, IN, Warrick County, IN, Bollinger County, MO, Cape Girardeau County, MO, Jefferson County, MO, Madison County, MO, Perry County, MO, Saint Francois County, MO, Sainte Genevieve County, MO, Wayne County, MO

The radar

The Evansville,IN radar (KVWX), 126 km from the middle of the area, began a volume at 20:03 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
40%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 13, 4:08 PM CDTFlash Flood WarningILXClay, Effingham, Jasper4 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, 8.0 hours before the alert went out and 213 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 12:00Z on 2009-05-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 36 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 12:00Z on 2009-05-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 586 square meters per square second.19395878Sfc1 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
36 J/kg
Mixed-layer CIN
-314 J/kg
Mixed-layer LCL
538 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
586 m²/s²
0-3 km storm-relative helicity
759 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 13, 9:27 AM CDTMesoscale DiscussionSPCAdams, Bond, Brown, Calhoun, Cass, Champaign and 54 more63 min
May 13, 1:15 PM CDTMesoscale DiscussionSPCBond, Clinton, Franklin, Jackson, Jefferson, Macoupin and 7 more30 min
May 13, 1:52 PM CDTMesoscale DiscussionSPCAdams, Brown, Calhoun, Greene, Hancock, Jersey and 3 more23 min
May 13, 2:39 PM CDTTornado WatchSPCAdams, Brown, Bureau, Calhoun, Cass, Fulton and 16 more7 hr
May 13, 5:47 PM CDTMesoscale DiscussionSPCAdams, Boone, Brown, Bureau, Carroll, Cass and 50 more88 min
May 13, 6:02 PM CDTTornado WatchSPCBoone, Champaign, Cook, DeKalb, DeWitt, DuPage and 26 more5 hr
May 13, 6:05 PM CDTMesoscale DiscussionSPCClark, Clay, Crawford, Edwards, Effingham, Franklin and 17 more85 min
May 13, 4:51 PM CDTSevere Thunderstorm WatchSPCBarton, Bates, Benton, Boone, Caldwell, Camden and 26 more6 hr
May 13, 6:30 PM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Carroll, Cass, Cooper and 11 more90 min

Nearby

Tornado Watches in Illinois, 2009Tornado Watches in Indiana, 2009Tornado Watches in Missouri, 2009Every tornado watch in 2009

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.