Alert archive / Missouri / Tornado Watches in 2010

Tornado Watch 157

May 12, 20104 counties in Kansas; 15 counties in Missouri

The Storm Prediction Center issued this tornado watch at May 12, 2010, 5:40 PM CDT for 4 counties in Kansas; 15 counties in Missouri. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 12, 2010, 5:40 PM CDT (22:40 UTC)
Expired
May 13, 2010, 12:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt

Counties Johnson County, KS, Leavenworth County, KS, Miami County, KS, Wyandotte County, KS, Caldwell County, MO, Carroll County, MO, Cass County, MO, Clay County, MO, Clinton County, MO, Cooper County, MO, Howard County, MO, Jackson County, MO, Johnson County, MO, Lafayette County, MO, Livingston County, MO, Pettis County, MO, Platte County, MO, Ray County, MO, Saline County, MO

The radar

The Pleasant Hill radar (KEAX), 37 km from the middle of the area, began a volume at 22:40 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

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

IssuedProductOfficeCountiesLasted
May 12, 5:41 PM CDTSevere Thunderstorm WarningEAXJohnson, Wyandotte34 min
May 12, 6:55 PM CDTSevere Thunderstorm WarningEAXJohnson, Leavenworth, Wyandotte50 min
May 12, 7:31 PM CDTSevere Thunderstorm WarningEAXLeavenworth, Wyandotte44 min
May 12, 7:33 PM CDTSevere Thunderstorm WarningEAXJohnson, Leavenworth, Wyandotte27 min
May 12, 8:16 PM CDTFlash Flood WarningEAXAtchison, Doniphan, Johnson, Leavenworth, Wyandotte9 hr
May 12, 8:28 PM CDTFlash Flood WarningEAXAdair, Caldwell, Carroll, Chariton, Daviess, Grundy and 7 more9 hr
May 12, 8:31 PM CDTSevere Thunderstorm WarningEAXCaldwell, Carroll, Clay, Jackson, Ray44 min
May 12, 10:44 PM CDTSevere Thunderstorm WarningEAXAtchison, Leavenworth31 min
May 12, 11:02 PM CDTSevere Thunderstorm WarningEAXJohnson, Leavenworth, Miami, Wyandotte28 min
May 12, 11:28 PM CDTSevere Thunderstorm WarningEAXJohnson, Leavenworth, Miami, Wyandotte47 min
May 12, 11:51 PM CDTTornado WarningEAXCaldwell, Clinton, Ray24 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 12:00Z, 10.7 hours before the alert went out and 138 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 12:00Z on 2010-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 joules per kilogram.LCLEL10008507005003002001001 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 12:00Z on 2010-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 734 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
6 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
453 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
734 m²/s²
0-3 km storm-relative helicity
915 m²/s²
Significant tornado parameter
0.0
Supercell composite
14.8

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 11, 7:54 PM CDTMesoscale DiscussionSPCBarber, Comanche, Harper, Kingman, Pratt, Sumner66 min
May 11, 8:11 PM CDTTornado WatchSPCBarber, Barton, Butler, Chase, Comanche, Cowley and 17 more8 hr
May 11, 8:40 PM CDTMesoscale DiscussionSPCAllen, Bourbon, Cherokee, Crawford, Labette, Montgomery and 3 more2 hr
May 11, 11:05 PM CDTMesoscale DiscussionSPCBarber, Barton, Butler, Chase, Chautauqua, Clark and 32 more25 min
May 11, 11:16 PM CDTSevere Thunderstorm WatchSPCAllen, Anderson, Barber, Barton, Bourbon, Butler and 54 more6 hr
May 12, 2:34 AM CDTMesoscale DiscussionSPCAllen, Anderson, Barber, Barton, Bourbon, Butler and 60 more56 min
May 12, 2:21 PM CDTMesoscale DiscussionSPCAllen, Anderson, Barber, Butler, Chase, Coffey and 21 more54 min
May 12, 2:41 PM CDTTornado WatchSPCAnderson, Butler, Chase, Coffey, Cowley, Dickinson and 20 more7 hr
May 12, 5:14 PM CDTMesoscale DiscussionSPCAnderson, Bourbon, Franklin, Johnson, Leavenworth, Linn and 2 more91 min
May 12, 6:59 PM CDTMesoscale DiscussionSPCBarber, Butler, Chase, Coffey, Cowley, Dickinson and 13 more61 min
May 12, 4:51 AM CDTMesoscale DiscussionSPCBenton, Cole, Franklin, Gasconade, Henry, Jefferson and 9 more54 min

Nearby

Tornado Watches in Missouri, 2010Tornado Watches in Kansas, 2010Every tornado watch in 2010

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.