Alert archive / Kansas / Severe Thunderstorm Watches in 2017
Severe Thunderstorm Watch 502
The Storm Prediction Center issued this severe thunderstorm watch at Oct 21, 2017, 2:23 PM CDT for 37 counties in Kansas; 24 counties in Missouri. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Oct 21, 2017, 2:23 PM CDT (19:23 UTC)
- Expired
- Oct 21, 2017, 10:00 PM CDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 61 counties
Allen County, KS, Anderson County, KS, Atchison County, KS, Brown County, KS, Butler County, KS, Chase County, KS, Chautauqua County, KS, Coffey County, KS, Cowley County, KS, Doniphan County, KS, Douglas County, KS, Elk County, KS, Franklin County, KS, Greenwood County, KS, Harper County, KS, Harvey County, KS, Jackson County, KS, Jefferson County, KS, Johnson County, KS, Labette County, KS, Leavenworth County, KS, Linn County, KS, Lyon County, KS, Marion County, KS, Miami County, KS, Montgomery County, KS, Morris County, KS, Neosho County, KS, Osage County, KS, Pottawatomie County, KS, Sedgwick County, KS, Shawnee County, KS, Sumner County, KS, Wabaunsee County, KS, Wilson County, KS, Woodson County, KS, Wyandotte County, KS, Andrew County, MO, Atchison County, MO, Bates County, MO, Buchanan County, MO, Caldwell County, MO, Carroll County, MO, Cass County, MO, Clay County, MO, Clinton County, MO, Daviess County, MO, DeKalb County, MO, Gentry County, MO, Grundy County, MO, Harrison County, MO, Holt County, MO, Jackson County, MO, Johnson County, MO, Lafayette County, MO, Livingston County, MO, Mercer County, MO, Nodaway County, MO, Platte County, MO, Ray County, MO, Worth County, MO
The radar
The Pleasant Hill radar (KEAX), 68 km from the middle of the area, began a volume at 19:24 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
- 40%
- 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
- 10%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 21, 3:05 PM CDT | Severe Thunderstorm Warning | TOP | Jackson, Pottawatomie, Shawnee, Wabaunsee | 40 min |
| Oct 21, 3:13 PM CDT | Severe Thunderstorm Warning | TOP | Jackson | 47 min |
| Oct 21, 3:44 PM CDT | Severe Thunderstorm Warning | EAX | Atchison, Doniphan | 31 min |
| Oct 21, 3:53 PM CDT | Severe Thunderstorm Warning | ICT | Butler, Sedgwick | 29 min |
| Oct 21, 4:07 PM CDT | Severe Thunderstorm Warning | TOP | Lyon, Wabaunsee | 53 min |
| Oct 21, 4:30 PM CDT | Severe Thunderstorm Warning | EAX | Atchison, Holt, Nodaway | 30 min |
| Oct 21, 4:57 PM CDT | Severe Thunderstorm Warning | EAX | Atchison, Doniphan | 33 min |
| Oct 21, 5:04 PM CDT | Severe Thunderstorm Warning | TOP | Douglas, Franklin, Jefferson, Osage, Shawnee | 56 min |
| Oct 21, 6:05 PM CDT | Severe Thunderstorm Warning | TOP | Douglas, Jefferson | 25 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, 7.4 hours before the alert went out and 61 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.
- Mixed-layer CAPE
- 51 J/kg
- Mixed-layer CIN
- -387 J/kg
- Mixed-layer LCL
- 735 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 326 m²/s²
- 0-3 km storm-relative helicity
- 313 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 21, 1:23 PM CDT | Mesoscale Discussion | SPC | Allen, Anderson, Atchison, Brown, Butler, Chase and 34 more | 3 hr |
| Oct 21, 5:38 PM CDT | Mesoscale Discussion | SPC | Allen, Anderson, Atchison, Bourbon, Brown, Butler and 31 more | 67 min |
Nearby
Severe Thunderstorm Watches in Kansas, 2017Severe Thunderstorm Watches in Missouri, 2017Every 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.