Alert archive / Illinois / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 119

March 30, 201232 counties in Illinois; 5 counties in Indiana

The Storm Prediction Center issued this severe thunderstorm watch at Mar 30, 2012, 2:51 PM CDT for 32 counties in Illinois; 5 counties in Indiana. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Mar 30, 2012, 2:51 PM CDT (19:51 UTC)
Expired
Mar 30, 2012, 10:00 PM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 37 counties

Bond County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Edgar 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, Lawrence County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Perry County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Shelby County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Gibson County, IN, Pike County, IN, Posey County, IN, Vanderburgh County, IN, Warrick County, IN

The radar

The Evansville,IN radar (KVWX), 104 km from the middle of the area, began a volume at 19:54 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

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

IssuedProductOfficeCountiesLasted
Mar 30, 3:15 PM CDTSevere Thunderstorm WarningLSXClinton, Fayette, Marion30 min
Mar 30, 3:17 PM CDTSevere Thunderstorm WarningILXClark, Crawford, Jasper58 min
Mar 30, 3:20 PM CDTSevere Thunderstorm WarningLSXFayette, Marion25 min
Mar 30, 3:24 PM CDTSevere Thunderstorm WarningILXClay, Effingham, Jasper54 min
Mar 30, 3:42 PM CDTSevere Thunderstorm WarningILXCumberland33 min
Mar 30, 3:45 PM CDTSevere Thunderstorm WarningLSXFayette, Marion30 min
Mar 30, 4:15 PM CDTSevere Thunderstorm WarningILXClark, Cumberland36 min
Mar 30, 4:43 PM CDTSevere Thunderstorm WarningLSXClinton32 min
Mar 30, 5:06 PM CDTSevere Thunderstorm WarningLSXMarion24 min
Mar 30, 5:15 PM CDTSevere Thunderstorm WarningLSXClinton15 min
Mar 30, 5:29 PM CDTSevere Thunderstorm WarningLSXClinton, Marion31 min
Mar 30, 5:39 PM CDTSevere Thunderstorm WarningPAHWayne18 min
Mar 30, 5:47 PM CDTSevere Thunderstorm WarningPAHJackson, Perry28 min
Mar 30, 8:29 PM CDTSevere Thunderstorm WarningPAHSpencer, Warrick31 min
Mar 30, 9:19 PM CDTSevere Thunderstorm WarningPAHPosey, Vanderburgh, Warrick26 min
Mar 30, 9:41 PM CDTSevere Thunderstorm WarningPAHHamilton, White14 min
Mar 30, 9:50 PM CDTSevere Thunderstorm WarningPAHEdwards, Wayne25 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

Lincoln, IL (KILX), launched 12:00Z, 7.9 hours before the alert went out and 145 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 2012-03-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 164 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 2012-03-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 206 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
164 J/kg
Mixed-layer CIN
-244 J/kg
Mixed-layer LCL
1045 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
206 m²/s²
0-3 km storm-relative helicity
230 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
Mar 30, 1:12 PM CDTMesoscale DiscussionSPCBond, Clark, Clay, Clinton, Coles, Crawford and 25 more93 min
Mar 30, 2:24 PM CDTSevere Thunderstorm WatchSPCAdams, Allen, Bartholomew, Blackford, Boone, Brown and 44 more7 hr
Mar 30, 6:02 PM CDTMesoscale DiscussionSPCBartholomew, Brown, Clay, Daviess, Dearborn, Decatur and 23 more28 min
Mar 29, 8:30 PM CDTSevere Thunderstorm WatchSPCDaviess, DeKalb, Gentry, Grundy, Harrison, Linn and 5 more6 hr
Mar 29, 9:51 PM CDTMesoscale DiscussionSPCAndrew, Atchison, Buchanan, Holt, Nodaway54 min
Mar 29, 11:50 PM CDTMesoscale DiscussionSPCGentry, Grundy, Harrison, Mercer, Putnam, Sullivan and 1 more55 min

Nearby

Severe Thunderstorm Watches in Illinois, 2012Severe Thunderstorm Watches in Indiana, 2012Every 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.