Alert archive / Kansas / Tornado Watches in 2015

Tornado Watch 136

May 6, 201534 counties in Kansas; 11 counties in Nebraska

The Storm Prediction Center issued this tornado watch at May 6, 2015, 8:31 PM CDT for 34 counties in Kansas; 11 counties in Nebraska. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: May 6, 2015, 8:31 PM CDT (01:31 UTC)
Expired: May 7, 2015, 2:00 AM CDT
In force: 5 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 60 kt

All 45 counties

Butler County, KS, Chase County, KS, Chautauqua County, KS, Clay County, KS, Cloud County, KS, Cowley County, KS, Dickinson County, KS, Elk County, KS, Ellsworth County, KS, Geary County, KS, Greenwood County, KS, Harper County, KS, Harvey County, KS, Jewell County, KS, Kingman County, KS, Lincoln County, KS, Lyon County, KS, Marion County, KS, Marshall County, KS, McPherson County, KS, Mitchell County, KS, Morris County, KS, Nemaha County, KS, Ottawa County, KS, Pottawatomie County, KS, Reno County, KS, Republic County, KS, Rice County, KS, Riley County, KS, Saline County, KS, Sedgwick County, KS, Sumner County, KS, Wabaunsee County, KS, Washington County, KS, Cass County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE, Saline County, NE, Thayer County, NE

The radar

The Topeka radar (KTWX), 81 km from the middle of the area, began a volume at 01:32 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: 10%
Ten or more severe hail reports: 30%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 70%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
May 6, 8:33 PM CDT	Tornado Warning	OAX	Lancaster	27 min
May 6, 8:34 PM CDT	Flash Flood Warning	OAX	Jefferson, Saline	4 hr
May 6, 8:38 PM CDT	Tornado Warning	GID	Jewell	37 min
May 6, 8:43 PM CDT	Tornado Warning Tornado observed	TOP	Ottawa	17 min
May 6, 8:46 PM CDT	Severe Thunderstorm Warning	OAX	Jefferson, Saline	44 min
May 6, 8:52 PM CDT	Severe Thunderstorm Warning	TOP	Cloud, Republic, Washington	53 min
May 6, 8:58 PM CDT	Tornado Warning	TOP	Clay, Cloud, Ottawa	32 min
May 6, 9:04 PM CDT	Tornado Warning	TOP	Republic	29 min
May 6, 9:13 PM CDT	Tornado Warning	GID	Jewell	32 min
May 6, 9:14 PM CDT	Tornado Warning	TOP	Washington	31 min
May 6, 9:26 PM CDT	Tornado Warning	TOP	Clay, Cloud	34 min
May 6, 9:35 PM CDT	Severe Thunderstorm Warning	GID	Jewell	40 min
May 6, 9:35 PM CDT	Severe Thunderstorm Warning	OAX	Gage, Jefferson	40 min
May 6, 9:36 PM CDT	Severe Thunderstorm Warning	TOP	Washington	24 min
May 6, 9:43 PM CDT	Tornado Warning	GID	Jewell	32 min
May 6, 9:50 PM CDT	Tornado Warning Tornado observed	TOP	Clay, Cloud, Washington	25 min
May 6, 9:56 PM CDT	Flash Flood Warning	OAX	Gage, Lancaster, Saline, Seward	3 hr
May 6, 10:08 PM CDT	Tornado Warning	GID	Jewell	23 min
May 6, 10:11 PM CDT	Tornado Warning	TOP	Washington	34 min
May 6, 10:12 PM CDT	Severe Thunderstorm Warning	GID	Jewell	48 min
May 6, 10:21 PM CDT	Severe Thunderstorm Warning	OAX	Gage	39 min
May 6, 10:38 PM CDT	Tornado Warning	OAX	Gage, Lancaster	24 min
May 6, 10:39 PM CDT	Tornado Warning	TOP	Washington	36 min
May 6, 10:43 PM CDT	Severe Thunderstorm Warning	GID	Thayer	32 min
May 6, 10:52 PM CDT	Severe Thunderstorm Warning	GID	Thayer	38 min
May 6, 10:53 PM CDT	Tornado Warning	OAX	Gage, Jefferson	37 min
May 6, 11:00 PM CDT	Tornado Warning	OAX	Gage, Lancaster, Otoe	30 min
May 6, 11:21 PM CDT	Severe Thunderstorm Warning	OAX	Cass, Otoe	39 min
May 7, 12:28 AM CDT	Flash Flood Warning	OAX	Gage, Jefferson, Lancaster, Saline, Seward	7 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

Topeka, KS (KFOE), launched 00:00Z, 1.5 hours before the alert went out and 127 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: 498 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 1054 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 263 m²/s²
0-3 km storm-relative helicity: 410 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 9.6

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 6, 7:40 PM CDT	Mesoscale Discussion	SPC	Fremont, Mills, Montgomery, Page	65 min
May 6, 9:40 PM CDT	Mesoscale Discussion	SPC	Barton, Butler, Chase, Clay, Cloud, Dickinson and 29 more	95 min
May 6, 11:17 PM CDT	Mesoscale Discussion	SPC	Brown, Butler, Chase, Clay, Cloud, Cowley and 27 more	88 min
May 7, 1:44 PM CDT	Mesoscale Discussion	SPC	Barber, Barton, Clay, Dickinson, Edwards, Ellsworth and 23 more	2 hr
May 7, 2:47 PM CDT	Mesoscale Discussion	SPC	Grant, Hamilton, Haskell, Kearny, Morton, Stanton and 1 more	118 min

Nearby

Tornado Watches in Kansas, 2015 Tornado Watches in Nebraska, 2015 Every tornado watch in 2015

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.