Alert archive / Missouri / Flash Flood Warnings in 2021

Flash Flood Warning 3, NWS Kansas City, MO

April 28, 2021Cass County, Missouri

NWS Kansas City, MO issued this flash flood warning at Apr 28, 2021, 5:00 PM CDT for Cass County, Missouri. It was in force for 3 hr. 7 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 28, 2021, 5:00 PM CDT (22:00 UTC)
Expired: Apr 28, 2021, 8:00 PM CDT
In force: 3 hr
Issued by: NWS Kansas City, MO
Area: Storm-based polygon
Flood severity: None

County Cass County, MO

The radar

The Pleasant Hill radar (KEAX), 29 km from the middle of the area, began a volume at 22:02 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 was reported inside it

Time	Report	Where	Remark
Apr 28, 5:13 PM CDT	FLASH FLOOD	Peculiar, MO	SEVERAL REPORTS OF FLOODING IN AND AROUND PECULIAR.
Apr 28, 5:16 PM CDT	FLASH FLOOD	5 N Harrisonville, MO	FLOODING REPORTED.
Apr 28, 5:18 PM CDT	FLASH FLOOD	5 Ssw Lake Winnebago, MO	FLOODED ROADWAY ALONG HIGHWAY 291.
Apr 28, 5:31 PM CDT	FLASH FLOOD	2 Nne Peculiar, MO	WATER OVER ROAD.
Apr 28, 5:43 PM CDT	FLASH FLOOD	West Line, MO	WATER OVER ROAD.
Apr 28, 7:00 PM CDT	HEAVY RAIN 2.26	2 Nne Pleasant Hill, MO
Apr 28, 7:00 PM CDT	HEAVY RAIN 2.7	Raymore, MO

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 10.0 hours before the alert went out and 101 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: 986 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 592 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 168 m²/s²
0-3 km storm-relative helicity: 167 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.1

Open this sounding in Storm Lab

The text

As transmitted.

062 
WGUS53 KEAX 282200
FFWEAX
MOC037-290100-
/O.NEW.KEAX.FF.W.0003.210428T2200Z-210429T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Kansas City/Pleasant Hill MO
500 PM CDT Wed Apr 28 2021

The National Weather Service in Pleasant Hill MO has issued a

* Flash Flood Warning for...
  Northwestern Cass County in west central Missouri...

* Until 800 PM CDT.

* At 500 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 0.5 to 1 inch are 
  possible in the warned area. Flash flooding is already occurring.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Belton, Raymore, Pleasant Hill, Peculiar, Lake Winnebago, 
  Cleveland, Freeman, Lake Annette, Baldwin Park and West Line.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3868 9461 3879 9457 3883 9423 3874 9423
      3858 9461 3859 9461 3862 9461 3863 9461
      3864 9461 3865 9461 3866 9461 3867 9461

FLASH FLOOD...RADAR INDICATED

$$

73

1 follow-up statement

409 
WGUS73 KEAX 290059
FFSEAX

Flash Flood Statement
National Weather Service Kansas City/Pleasant Hill MO
759 PM CDT Wed Apr 28 2021

MOC037-290109-
/O.EXP.KEAX.FF.W.0003.000000T0000Z-210429T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cass MO-
759 PM CDT Wed Apr 28 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 8 PM CDT THIS EVENING FOR 
NORTHWESTERN CASS COUNTY...

The heavy rain has ended however flooding is ongoing in the warned 
area and the flash flood warning has been replaced by a areal flood 
warning. Please continue to heed remaining road closures and do not 
drive into water covered roadways.

LAT...LON 3868 9461 3879 9457 3883 9423 3874 9423
      3858 9461 3859 9461 3862 9461 3863 9461
      3864 9461 3865 9461 3866 9461 3867 9461

$$

73

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 28, 8:26 AM CDT	River Flood Warning	EAX	Cass, Henry, Johnson	67 hr
Apr 28, 3:04 PM CDT	Flash Flood Warning	EAX	Platte	3 hr
Apr 28, 4:04 PM CDT	Areal Flood Advisory	EAX	Caldwell, Carroll, Clay, Clinton, Livingston, Ray	3 hr
Apr 28, 4:48 PM CDT	Areal Flood Advisory	EAX	Cass, Johnson	3 hr

Nearby

Flash Flood Warnings in Missouri, 2021 Every flash flood 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.