Alert archive / Missouri / Special Weather Statements in 2021

Special Weather Statement, NWS Kansas City, MO

August 12, 2021Cass County, Missouri

NWS Kansas City, MO issued this special weather statement at Aug 12, 2021, 6:15 PM CDT for Cass County, Missouri. It was in force for 45 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: Aug 12, 2021, 6:15 PM CDT (23:15 UTC)
Expired: Aug 12, 2021, 7:00 PM CDT
In force: 45 min
Issued by: NWS Kansas City, MO
Hail: 0.00 in
Wind: 40

County Cass County, MO

The radar

The Pleasant Hill radar (KEAX), 21 km from the middle of the area, began a volume at 23:16 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 nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 11.3 hours before the alert went out and 116 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: 951 J/kg
Mixed-layer CIN: -437 J/kg
Mixed-layer LCL: 1729 m above ground
0-6 km bulk shear: 3 kt
0-1 km storm-relative helicity: 141 m²/s²
0-3 km storm-relative helicity: 228 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.9

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Kansas City, MO wrote its last area forecast discussion before this special weather statement went out at Aug 12, 4:41 PM CDT, 1 hour 34 minutes earlier.

Area forecast discussion, Aug 12, 4:41 PM CDT, 1 hour 34 minutes before

AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
441 PM CDT Thu Aug 12 2021

.Discussion...
Issued at 440 PM CDT THU AUG 12 2021

Thunderstorms are ongoing from Moberly west through Leavenworth
along an outflow boundary. Several of these storms have been
severe, producing wind gusts up to 60 mph and hail up to quarter
size. Flash flooding has also been a concern, especially across
northeastern Missouri. These storms will continue to move to the
southeast over the next few hours. An additional round of showers
and thunderstorms are expected to redevelop later this evening and
into the overnight period as the cold front finally makes its way
southward. These storms will also pose a threat for wind gusts up
to 60 mph, small hail, moderate to heavy rainfall, and frequent
lightning.

A few showers may linger through mid Friday morning, with all
activity moved out by noon. With the cold front to our south, high
temperatures are only expected to reach the mid 80s tomorrow. The
cold front pushes further south into the southeastern US by
Saturday with mid level troughing remaining overhead. This will
keep highs in the mid 80s and dewpoints moderated through Monday.
Warmer and more humid conditions look to return by mid week.

&&

.Aviation...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 112 AM CDT THU AUG 12 2021

Showers and thunderstorms are ongoing along a corridor from
northeast Missouri to northeastern Kansas. This activity should
only impact STJ through the next several hours. However, as the
front progresses southward this evening, convection should shift
southward with it. Thunderstorms should impact all terminals
between roughly 2z and 8z tonight before finally moving off to the
south. Brief periods of strong wind gusts, moderate to heavy
rain, and reduced visibilities will all be possible during this
time. Otherwise, VFR conditions are expected to prevail with winds
shifting to east northeasterly by late tonight.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...Heat Advisory until 8 PM CDT this evening for KSZ025-057-060-102.

     Excessive Heat Warning until 8 PM CDT this evening for
     KSZ103>105.

MO...Heat Advisory until 8 PM CDT this evening for MOZ001>004-011>013-
     020>022-030>033-038>040-043>046-053-054.

     Excessive Heat Warning until 8 PM CDT this evening for MOZ028-
     029-037.

     Flash Flood Watch through Friday morning for MOZ007-008.

&&

Discussion...BMW
Aviation...BMW

Hazardous weather outlook, Aug 12, 5:19 AM CDT, 12 hours 56 minutes before

Hazardous Weather Outlook
National Weather Service Kansas City/Pleasant Hill MO
519 AM CDT Thu Aug 12 2021

KSZ025-057-060-102>105-MOZ001>008-011>017-020>025-028>033-037>040-
043>046-053-054-131030-
Atchison KS-Miami-Linn KS-Doniphan-Leavenworth-Wyandotte-Johnson KS-
Atchison MO-Nodaway-Worth-Gentry-Harrison-Mercer-Putnam-Schuyler-
Holt-Andrew-De Kalb-Daviess-Grundy-Sullivan-Adair-Buchanan-Clinton-
Caldwell-Livingston-Linn MO-Macon-Platte-Clay-Ray-Carroll-Chariton-
Randolph-Jackson-Lafayette-Saline-Howard-Cass-Johnson MO-Pettis-
Cooper-Bates-Henry-
519 AM CDT Thu Aug 12 2021

This hazardous weather outlook is for northwest...north central and
west central Missouri...as well as extreme eastern Kansas.

.DAY ONE...Today and Tonight

 A few showers and storms are possible early this morning. The
 Excessive Heat Warning for area surrounding the KC Metro and the
 Heat Advisory for everywhere else is in effect until 8pm tonight
 due to morning temps in the upper 70s, lower 80s and ongoing heat
 with indices around 105-110 degree F. Another chance for storms is
 tonight after 4-5pm. Strong, damaging wind and frequent lightning
 are the main concern with these developing storms.

 More detailed information can be accessed at...
 https://www.weather.gov/eax/hwo

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

 A cool-down is expected by Friday with max temps in the 80s and heat
 indices following closely behind.

 More detailed information can be accessed at...
 https://www.weather.gov/eax/hwo

In the hours before

Local storm report, Aug 12, 5:47 PM CDT, 28 minutes before

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Local storm report, Aug 12, 6:00 PM CDT, 15 minutes before

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Local storm report, Aug 12, 6:01 PM CDT, 14 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
601 PM CDT THU AUG 12 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0400 PM     TSTM WND GST     KANSAS CITY INTL AIRPOR 39.30N 94.72W
08/12/2021  E60 MPH          PLATTE             MO   TRAINED SPOTTER

&&

BMW

Local storm report, Aug 12, 6:03 PM CDT, 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
603 PM CDT THU AUG 12 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0552 PM     TSTM WND GST     1 SW RAYMORE            38.79N 94.47W
08/12/2021  E60 MPH          CASS               MO   NWS EMPLOYEE

&&

BMW

Local storm report, Aug 12, 6:07 PM CDT, 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
607 PM CDT THU AUG 12 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0550 PM     TSTM WND DMG     4 W PLEASANT HILL       38.79N 94.34W
08/12/2021                   CASS               MO   EMERGENCY MNGR

            TREE DOWNED AND BLOCKING HIGHWAY 58 AT GRAY ROAD

&&

BMW

Special weather statement, Aug 12, 6:15 PM CDT, 0 minutes before

Special Weather Statement
National Weather Service Kansas City/Pleasant Hill MO
615 PM CDT Thu Aug 12 2021

KSZ057-MOZ043-044-053-054-130000-
Miami KS-Bates MO-Cass MO-Johnson MO-Henry MO-
615 PM CDT Thu Aug 12 2021

...A strong thunderstorm will impact portions of northeastern Miami,
Cass, northwestern Henry, northwestern Bates and southwestern Johnson
Counties through 700 PM CDT...

At 615 PM CDT, Doppler radar was tracking a strong thunderstorm near
Harrisonville, moving southeast at 25 mph.

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Raymore, Harrisonville, Pleasant Hill, Peculiar, Holden, Adrian,
Garden City, Archie, Lake Winnebago, Cleveland, Freeman, Creighton,
Chilhowee, East Lynne, Kingsville, Lake Annette, Baldwin Park,
Strasburg, Gunn City and Blairstown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

&&

LAT...LON 3835 9452 3874 9466 3874 9461 3877 9461
      3884 9418 3883 9415 3855 9380
TIME...MOT...LOC 2315Z 312DEG 21KT 3870 9435

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

HB

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 12, 4:29 AM CDT	Special Weather Statement	EAX	Harrison	31 min
Aug 12, 4:58 AM CDT	Special Weather Statement	EAX	Mercer	47 min
Aug 12, 5:31 AM CDT	Severe Thunderstorm Warning	EAX	Harrison, Mercer	29 min
Aug 12, 6:00 AM CDT	Special Weather Statement	EAX	Mercer	30 min
Aug 12, 8:37 AM CDT	Special Weather Statement	EAX	Schuyler	8 min
Aug 12, 8:38 AM CDT	Special Weather Statement	EAX	Schuyler	37 min
Aug 12, 1:27 PM CDT	Flash Flood Watch	EAX	Putnam, Schuyler	6 hr
Aug 12, 1:42 PM CDT	Special Weather Statement	EAX	Daviess, Grundy, Sullivan	48 min
Aug 12, 1:45 PM CDT	Special Weather Statement	EAX	Schuyler	30 min
Aug 12, 2:15 PM CDT	Flash Flood Warning	EAX	Putnam, Schuyler	2 hr
Aug 12, 2:16 PM CDT	Special Weather Statement	EAX	Caldwell, Linn, Livingston	29 min
Aug 12, 2:18 PM CDT	Severe Thunderstorm Warning	EAX	Grundy, Linn, Livingston	27 min
Aug 12, 2:31 PM CDT	Severe Thunderstorm Warning	EAX	Caldwell, Carroll, Daviess, Linn, Livingston	29 min
Aug 12, 2:49 PM CDT	Severe Thunderstorm Warning	EAX	Carroll, Chariton, Livingston	26 min
Aug 12, 3:13 PM CDT	Severe Thunderstorm Warning	EAX	Carroll, Chariton, Livingston, Saline	32 min
Aug 12, 3:28 PM CDT	Severe Thunderstorm Warning	EAX	Clay, Platte	32 min
Aug 12, 3:44 PM CDT	Severe Thunderstorm Warning	EAX	Chariton, Macon, Randolph	31 min
Aug 12, 3:53 PM CDT	Severe Thunderstorm Warning	EAX	Randolph	37 min
Aug 12, 3:56 PM CDT	Severe Thunderstorm Warning	EAX	Clay, Jackson, Platte	34 min
Aug 12, 4:09 PM CDT	Severe Thunderstorm Warning	EAX	Clay, Jackson, Lafayette, Ray, Saline	36 min
Aug 12, 4:42 PM CDT	Severe Thunderstorm Warning	EAX	Jackson, Johnson, Lafayette	33 min
Aug 12, 5:11 PM CDT	Severe Thunderstorm Warning	EAX	Cass, Jackson, Johnson, Lafayette	34 min
Aug 12, 5:18 PM CDT	Severe Thunderstorm Warning	EAX	Cass, Jackson	27 min
Aug 12, 5:22 PM CDT	Severe Thunderstorm Warning	EAX	Jackson	8 min
Aug 12, 5:37 PM CDT	Severe Thunderstorm Warning	EAX	Cass, Jackson, Johnson	8 min
Aug 12, 5:43 PM CDT	Severe Thunderstorm Warning	EAX	Cass, Jackson, Johnson	32 min

Nearby

Special Weather Statements in Missouri, 2021 Every special weather statement 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.