Alert archive / Kansas / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 546

November 10, 20215 counties in Iowa; 16 counties in Kansas; 13 counties in Missouri

The Storm Prediction Center issued this severe thunderstorm watch at Nov 10, 2021, 1:55 PM CST for 5 counties in Iowa; 16 counties in Kansas; 13 counties in Missouri. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Nov 10, 2021, 1:55 PM CST (19:55 UTC)
Expired
Nov 10, 2021, 8:00 PM CST
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
55 kt
All 34 counties

Adams County, IA, Decatur County, IA, Ringgold County, IA, Taylor County, IA, Union County, IA, Atchison County, KS, Brown County, KS, Coffey County, KS, Doniphan County, KS, Douglas County, KS, Franklin County, KS, Jackson County, KS, Jefferson County, KS, Leavenworth County, KS, Lyon County, KS, Morris County, KS, Nemaha County, KS, Osage County, KS, Pottawatomie County, KS, Shawnee County, KS, Wabaunsee County, KS, Andrew County, MO, Atchison County, MO, Buchanan County, MO, Caldwell County, MO, Clinton County, MO, Daviess County, MO, DeKalb County, MO, Gentry County, MO, Harrison County, MO, Holt County, MO, Nodaway County, MO, Platte County, MO, Worth County, MO

The radar

The Topeka radar (KTWX), 74 km from the middle of the area, began a volume at 19:56 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
20%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Nov 10, 2:18 PM CSTSevere Thunderstorm WarningEAXDoniphan27 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, 7.9 hours before the alert went out and 37 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 2021-11-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 24 joules per kilogram.LCLLFCEL10008507005003002001001 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 2021-11-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 136 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
24 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
634 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
136 m²/s²
0-3 km storm-relative helicity
154 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

222 
WWUS20 KWNS 101953
SEL6  
SPC WW 101953
IAZ000-KSZ000-MOZ000-110200-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 546
NWS Storm Prediction Center Norman OK
155 PM CST Wed Nov 10 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Southern Iowa
  East-central/Northeast Kansas
  Northwest Missouri

* Effective this Wednesday afternoon and evening from 155 PM
  until 800 PM CST.

* Primary threats include...
  Scattered damaging wind gusts to 65 mph possible
  Isolated large hail events to 1 inch in diameter possible
  A tornado or two possible

SUMMARY...Clusters of storms will continue to move northeastward
across the region as the air mass continues to modestly destabilize
through the afternoon, with periodic severe storms a possibility
through late afternoon/early evening.

The severe thunderstorm watch area is approximately along and 50
statute miles east and west of a line from 15 miles east southeast
of Emporia KS to 30 miles northwest of Lamoni IA. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU6).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 55 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
21035.

...Guyer

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 10, 3:46 PM CSTMesoscale DiscussionSPCBoone, Clarke, Dallas, Decatur, Jasper, Lucas and 8 more119 min
Nov 10, 10:53 AM CSTMesoscale DiscussionSPCAtchison, Brown, Chase, Clay, Dickinson, Geary and 10 more2 hr
Nov 10, 3:26 PM CSTSevere Thunderstorm WatchSPCChautauqua, Elk, Greenwood, Montgomery, Wilson, Woodson7 hr
Nov 10, 5:29 PM CSTMesoscale DiscussionSPCAnderson, Atchison, Coffey, Douglas, Franklin, Jefferson and 8 more2 hr

Nearby

Severe Thunderstorm Watches in Kansas, 2021Severe Thunderstorm Watches in Missouri, 2021Severe Thunderstorm Watches in Iowa, 2021Every severe thunderstorm watch in 2021

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.