Alert archive / Missouri / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 129, NWS Kansas City, MO

September 20, 2021Harrison County, Worth County, Missouri

NWS Kansas City, MO issued this severe thunderstorm warning at Sep 20, 2021, 4:12 PM CDT for Harrison County, Worth County, Missouri. It was in force for 33 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, 4:12 PM CDT (21:12 UTC)
Expired: Sep 20, 2021, 4:45 PM CDT
In force: 33 min
Issued by: NWS Kansas City, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Harrison County, MO, Worth County, MO

The radar

The Des Moines radar (KDMX), 137 km from the middle of the area, began a volume at 21:10 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

Omaha, NE (KOAX), launched 12:00Z, 9.2 hours before the alert went out and 219 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: 493 J/kg
Mixed-layer CIN: -291 J/kg
Mixed-layer LCL: 1101 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 414 m²/s²
0-3 km storm-relative helicity: 540 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

421 
WUUS53 KEAX 202112
SVREAX
MOC081-227-202145-
/O.NEW.KEAX.SV.W.0129.210920T2112Z-210920T2145Z/

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

The National Weather Service in Pleasant Hill has issued a

* Severe Thunderstorm Warning for...
  Northeastern Worth County in northwestern Missouri...
  Northern Harrison County in north central Missouri...

* Until 445 PM CDT.

* At 411 PM CDT, a severe thunderstorm was located 10 miles west of
  Eagleville, or 13 miles south of Mount Ayr, moving east at 50 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...
  Allendale and Hatfield. 

This includes Interstate 35 in Missouri between mile markers 108 and
114.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4049 9377 4046 9429 4057 9435 4058 9377
TIME...MOT...LOC 2111Z 256DEG 45KT 4052 9417 

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

$$

Klaus

2 follow-up statements

360 
WWUS53 KEAX 202133
SVSEAX

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

MOC227-202141-
/O.CAN.KEAX.SV.W.0129.000000T0000Z-210920T2145Z/
Worth MO-
433 PM CDT Mon Sep 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN WORTH COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
Worth County. Therefore, the warning has been cancelled for Worth 
County only. The warning is still in effect for Harrison County.

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

LAT...LON 4049 9377 4046 9422 4047 9423 4057 9423
      4058 9383 4057 9377
TIME...MOT...LOC 2131Z 256DEG 45KT 4058 9384 

$$

MOC081-202145-
/O.CON.KEAX.SV.W.0129.000000T0000Z-210920T2145Z/
Harrison MO-
433 PM CDT Mon Sep 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM CDT
FOR NORTHERN HARRISON COUNTY...

At 431 PM CDT, a severe thunderstorm was located near Lamoni, or 11
miles southwest of Leon, moving east at 50 mph.

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

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Hatfield.

This includes Interstate 35 in Missouri between mile markers 108 and
114.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4049 9377 4046 9422 4047 9423 4057 9423
      4058 9383 4057 9377
TIME...MOT...LOC 2131Z 256DEG 45KT 4058 9384 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Klaus

469 
WWUS53 KEAX 202142
SVSEAX

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

MOC081-202152-
/O.EXP.KEAX.SV.W.0129.000000T0000Z-210920T2145Z/
Harrison MO-
442 PM CDT Mon Sep 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN HARRISON COUNTY WILL
EXPIRE AT 445 PM CDT...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.  However small hail and gusty winds are still
possible with this thunderstorm.

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

LAT...LON 4049 9377 4046 9422 4047 9423 4057 9423
      4058 9383 4057 9377
TIME...MOT...LOC 2142Z 256DEG 45KT 4061 9369 

$$

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, 4:36 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, 5:33 PM CDT	Severe Thunderstorm Warning	EAX	Clay, Clinton, Platte	42 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.