Alert archive / Kansas / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 177

April 22, 201137 counties in Kansas; 10 counties in Missouri

The Storm Prediction Center issued this severe thunderstorm watch at Apr 22, 2011, 2:48 AM CDT for 37 counties in Kansas; 10 counties in Missouri. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Apr 22, 2011, 2:48 AM CDT (07:48 UTC)
Expired
Apr 22, 2011, 6:54 AM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 47 counties

Anderson County, KS, Atchison County, KS, Brown County, KS, Chase County, KS, Clay County, KS, Cloud County, KS, Coffey County, KS, Dickinson County, KS, Doniphan County, KS, Douglas County, KS, Ellsworth County, KS, Franklin County, KS, Geary County, KS, Jackson County, KS, Jefferson County, KS, Johnson County, KS, Leavenworth County, KS, Lincoln County, KS, Linn County, KS, Lyon County, KS, Marion County, KS, Marshall County, KS, McPherson County, KS, Miami County, KS, Morris County, KS, Nemaha County, KS, Osage County, KS, Ottawa County, KS, Pottawatomie County, KS, Republic County, KS, Rice County, KS, Riley County, KS, Saline County, KS, Shawnee County, KS, Wabaunsee County, KS, Washington County, KS, Wyandotte County, KS, Andrew County, MO, Bates County, MO, Buchanan County, MO, Cass County, MO, Clay County, MO, Clinton County, MO, DeKalb County, MO, Holt County, MO, Jackson County, MO, Platte County, MO

The radar

The Topeka radar (KTWX), 31 km from the middle of the area, began a volume at 07:50 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
5%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
20%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
40%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 22, 3:36 AM CDTSevere Thunderstorm WarningTOPLyon, Osage, Wabaunsee24 min
Apr 22, 4:00 AM CDTSevere Thunderstorm WarningTOPOsage, Shawnee, Wabaunsee45 min
Apr 22, 4:06 AM CDTSevere Thunderstorm WarningTOPWabaunsee39 min
Apr 22, 4:22 AM CDTSevere Thunderstorm WarningTOPDouglas, Shawnee25 min
Apr 22, 4:42 AM CDTSevere Thunderstorm WarningEAXLeavenworth33 min
Apr 22, 4:45 AM CDTSevere Thunderstorm WarningTOPJefferson14 min
Apr 22, 5:21 AM CDTSevere Thunderstorm WarningEAXLeavenworth, Wyandotte39 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

Topeka, KS (KTOP), launched 00:00Z, 7.8 hours before the alert went out and 82 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, Topeka, KS at 00:00Z on 2011-04-22Temperature 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, Topeka, KS at 00:00Z on 2011-04-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 292 square meters per square second.1939587897Sfc1 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
1049 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
292 m²/s²
0-3 km storm-relative helicity
537 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
Apr 21, 11:27 PM CDTMesoscale DiscussionSPCAllen, Anderson, Atchison, Bourbon, Brown, Butler and 49 more3 hr
Apr 22, 5:18 AM CDTMesoscale DiscussionSPCAtchison, Brown, Doniphan, Douglas, Franklin, Jackson and 11 more87 min
Apr 22, 10:09 AM CDTMesoscale DiscussionSPCBollinger, Cape Girardeau, Crawford, Dent, Franklin, Gasconade and 17 more66 min
Apr 22, 10:44 AM CDTMesoscale DiscussionSPCBarry, Bollinger, Carter, Christian, Crawford, Dent and 19 more61 min
Apr 22, 1:04 PM CDTMesoscale DiscussionSPCBarry, Barton, Benton, Callaway, Camden, Cedar and 40 more116 min
Apr 22, 1:23 PM CDTMesoscale DiscussionSPCMcDonald, Newton97 min
Apr 22, 3:34 PM CDTTornado WatchSPCAudrain, Barry, Benton, Boone, Callaway, Camden and 46 more6 hr
Apr 22, 5:21 PM CDTMesoscale DiscussionSPCAudrain, Barry, Boone, Callaway, Camden, Christian and 36 more114 min
Apr 22, 5:27 PM CDTMesoscale DiscussionSPCCape Girardeau, Perry, Sainte Genevieve, Saint Francois33 min
Apr 22, 5:49 PM CDTTornado WatchSPCBollinger, Butler, Cape Girardeau, Carter, Iron, Madison and 9 more7 hr

Nearby

Severe Thunderstorm Watches in Kansas, 2011Severe Thunderstorm Watches in Missouri, 2011Every severe thunderstorm watch in 2011

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.