Alert archive / Missouri / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 134, NWS Kansas City, MO

September 20, 2021Clay County, Clinton County, Platte County, Missouri

NWS Kansas City, MO issued this severe thunderstorm warning at Sep 20, 2021, 5:33 PM CDT for Clay County, Clinton County, Platte County, Missouri. It was in force for 42 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Sep 20, 2021, 5:33 PM CDT (22:33 UTC)
Expired: Sep 20, 2021, 6:15 PM CDT
In force: 42 min
Issued by: NWS Kansas City, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Clay County, MO, Clinton County, MO, Platte County, MO

The radar

The Pleasant Hill radar (KEAX), 71 km from the middle of the area, began a volume at 22:36 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Sep 20, 3:25 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 10.6 hours before the alert went out and 106 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: 583 J/kg
Mixed-layer CIN: -288 J/kg
Mixed-layer LCL: 1142 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 59 m²/s²
0-3 km storm-relative helicity: 185 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

As transmitted.

582 
WUUS53 KEAX 202233
SVREAX
MOC047-049-165-202315-
/O.NEW.KEAX.SV.W.0134.210920T2233Z-210920T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Kansas City/Pleasant Hill MO
533 PM CDT Mon Sep 20 2021

The National Weather Service in Pleasant Hill has issued a

* Severe Thunderstorm Warning for...
  Northern Clay County in west central Missouri...
  Southern Clinton County in northwestern Missouri...
  Northeastern Platte County in west central Missouri...

* Until 615 PM CDT.

* At 533 PM CDT, a severe thunderstorm was located near Smithville,
  moving east at 25 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Smithville, Kearney, Trimble, Edgerton, Holt, Mosby, Prathersville,
  Ridgely and Hoover.

This includes Interstate 35 in Missouri between mile markers 21 and
36.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3938 9473 3953 9464 3951 9424 3927 9430
TIME...MOT...LOC 2233Z 278DEG 22KT 3941 9463 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Klaus

1 follow-up statement

849 
WWUS53 KEAX 202309
SVSEAX

Severe Weather Statement
National Weather Service Kansas City/Pleasant Hill MO
609 PM CDT Mon Sep 20 2021

MOC047-049-165-202317-
/O.EXP.KEAX.SV.W.0134.000000T0000Z-210920T2315Z/
Clay MO-Clinton MO-Platte MO-
609 PM CDT Mon Sep 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN CLAY...SOUTHERN
CLINTON AND NORTHEASTERN PLATTE COUNTIES WILL EXPIRE AT 615 PM CDT...
        
The storm which prompted the warning has weakened in southern 
Clinton and northern Clay counties. Therefore, the warning will be 
allowed to expire. However heavy rain and frequent lightning is 
still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for
northwestern and west central Missouri.

LAT...LON 3938 9473 3953 9464 3951 9424 3927 9430
TIME...MOT...LOC 2307Z 278DEG 22KT 3938 9438 

$$

Klaus

The office that day

Everything else NWS Kansas City, MO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 20, 4:00 PM CDT	Special Weather Statement	EAX	Buchanan	30 min
Sep 20, 4:12 PM CDT	Severe Thunderstorm Warning	EAX	Harrison, Worth	33 min
Sep 20, 4:36 PM CDT	Special Weather Statement	EAX	DeKalb	24 min
Sep 20, 4:57 PM CDT	Severe Thunderstorm Warning	EAX	Daviess, DeKalb, Gentry, Harrison	33 min
Sep 20, 5:13 PM CDT	Severe Thunderstorm Warning	EAX	Clay, Clinton, Platte	47 min
Sep 20, 5:29 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Jackson	46 min
Sep 20, 5:49 PM CDT	Special Weather Statement	EAX	Daviess	26 min
Sep 20, 6:00 PM CDT	Severe Thunderstorm Warning	EAX	Clay, Jackson	45 min
Sep 20, 6:13 PM CDT	Severe Thunderstorm Warning	EAX	Bates	47 min
Sep 20, 6:23 PM CDT	Severe Thunderstorm Warning	EAX	Clay, Jackson, Ray	52 min
Sep 20, 6:34 PM CDT	Special Weather Statement	EAX	Cass	26 min
Sep 20, 6:47 PM CDT	Severe Thunderstorm Warning	EAX	Carroll, Lafayette, Ray	43 min

Nearby

Severe Thunderstorm Warnings in Missouri, 2021 Every severe thunderstorm warning 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.