Alert archive / Kansas / Severe Thunderstorm Watches in 2017

Severe Thunderstorm Watch 495

October 6, 201726 counties in Kansas; 10 counties in Nebraska

The Storm Prediction Center issued this severe thunderstorm watch at Oct 6, 2017, 3:47 PM CDT for 26 counties in Kansas; 10 counties in Nebraska. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Oct 6, 2017, 3:47 PM CDT (20:47 UTC)
Expired: Oct 6, 2017, 11:00 PM CDT
In force: 7 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 65 kt

All 36 counties

Barton County, KS, Brown County, KS, Clay County, KS, Cloud County, KS, Dickinson County, KS, Ellsworth County, KS, Geary County, KS, Harvey County, KS, Jackson County, KS, Kingman County, KS, Lincoln County, KS, Marion County, KS, Marshall County, KS, McPherson 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, Russell County, KS, Saline 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

The radar

The Topeka radar (KTWX), 114 km from the middle of the area, began a volume at 20:49 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: 10%
Ten or more severe wind reports: 50%
One or more gusts of 65 knots or more: 40%
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: 60%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Oct 6, 5:35 PM CDT	Severe Thunderstorm Warning	TOP	Marshall, Nemaha	25 min
Oct 6, 5:37 PM CDT	Severe Thunderstorm Warning	OAX	Nemaha, Pawnee, Richardson	23 min
Oct 6, 5:47 PM CDT	Severe Thunderstorm Warning	ICT	Barton	58 min
Oct 6, 6:37 PM CDT	Severe Thunderstorm Warning	ICT	Barton, Ellsworth, Rice	53 min
Oct 6, 6:54 PM CDT	Severe Thunderstorm Warning	TOP	Cloud, Ottawa	66 min
Oct 6, 7:02 PM CDT	Severe Thunderstorm Warning	ICT	Barton, Russell	41 min
Oct 6, 7:16 PM CDT	Tornado Warning	TOP	Cloud, Ottawa	29 min
Oct 6, 7:17 PM CDT	Tornado Warning	ICT	Ellsworth, McPherson, Rice, Saline	43 min
Oct 6, 7:35 PM CDT	Severe Thunderstorm Warning	OAX	Lancaster, Saline, Seward	25 min
Oct 6, 7:38 PM CDT	Severe Thunderstorm Warning	ICT	Barton, Ellsworth, Russell	52 min
Oct 6, 7:44 PM CDT	Severe Thunderstorm Warning	TOP	Cloud, Ottawa	61 min
Oct 6, 7:49 PM CDT	Tornado Warning	TOP	Cloud	26 min
Oct 6, 7:56 PM CDT	Severe Thunderstorm Warning	OAX	Lancaster, Saline	34 min
Oct 6, 8:21 PM CDT	Severe Thunderstorm Warning	TOP	Clay, Republic, Washington	39 min
Oct 6, 8:23 PM CDT	Severe Thunderstorm Warning	ICT	Ellsworth, Lincoln, Saline	55 min
Oct 6, 8:44 PM CDT	Severe Thunderstorm Warning	ICT	Ellsworth, Lincoln, McPherson, Rice, Saline	35 min
Oct 6, 8:56 PM CDT	Severe Thunderstorm Warning	TOP	Ottawa	34 min
Oct 6, 9:21 PM CDT	Tornado Warning	TOP	Clay, Dickinson, Ottawa	9 min
Oct 6, 9:37 PM CDT	Severe Thunderstorm Warning	ICT	McPherson, Rice, Saline	33 min
Oct 6, 9:55 PM CDT	Severe Thunderstorm Warning	TOP	Geary, Pottawatomie, Riley, Wabaunsee	35 min
Oct 6, 10:17 PM CDT	Severe Thunderstorm Warning	TOP	Jackson, Marshall, Nemaha, Pottawatomie	28 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 (KFOE), launched 12:00Z, 8.8 hours before the alert went out and 165 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: 126 J/kg
Mixed-layer CIN: -71 J/kg
Mixed-layer LCL: 650 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 225 m²/s²
0-3 km storm-relative helicity: 218 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 6, 3:14 PM CDT	Mesoscale Discussion	SPC	Audubon, Calhoun, Carroll, Cass, Crawford, Fremont and 6 more	91 min
Oct 6, 2:55 PM CDT	Mesoscale Discussion	SPC	Barton, Edwards, Ellis, Ellsworth, Finney, Ford and 25 more	2 hr
Oct 6, 3:31 PM CDT	Severe Thunderstorm Watch	SPC	Barber, Clark, Comanche, Edwards, Ellis, Finney and 28 more	7 hr
Oct 6, 6:06 PM CDT	Mesoscale Discussion	SPC	Barber, Barton, Clark, Comanche, Edwards, Ellis and 34 more	84 min
Oct 6, 6:50 PM CDT	Mesoscale Discussion	SPC	Chase, Clay, Cloud, Dickinson, Ellsworth, Geary and 17 more	85 min
Oct 6, 4:46 PM CDT	Mesoscale Discussion	SPC	Adams, Antelope, Boone, Buffalo, Burt, Butler and 33 more	2 hr

Nearby

Severe Thunderstorm Watches in Kansas, 2017 Severe Thunderstorm Watches in Nebraska, 2017 Every severe thunderstorm watch in 2017

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.