Alert archive / Missouri / Flash Flood Warnings in 2021

Flash Flood Warning 27, NWS Kansas City, MO

June 30, 20214 counties in Missouri; Johnson County, Leavenworth County, Wyandotte County, Kansas

NWS Kansas City, MO issued this flash flood warning at Jun 30, 2021, 8:38 AM CDT for 4 counties in Missouri; Johnson County, Leavenworth County, Wyandotte County, Kansas. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 30, 2021, 8:38 AM CDT (13:38 UTC)
Expired
Jun 30, 2021, 12:22 PM CDT
In force
4 hr
Issued by
NWS Kansas City, MO
Area
Storm-based polygon
Flood severity
None

Counties Johnson County, KS, Leavenworth County, KS, Wyandotte County, KS, Clay County, MO, Jackson County, MO, Platte County, MO, Ray County, MO

The radar

The Pleasant Hill radar (KEAX), 37 km from the middle of the area, began a volume at 13:40 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, 1.6 hours before the alert went out and 110 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 2021-06-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 247 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Topeka, KS at 12:00Z on 2021-06-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 21 square meters per square second.193958Sfc1 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
247 J/kg
Mixed-layer CIN
-22 J/kg
Mixed-layer LCL
653 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
21 m²/s²
0-3 km storm-relative helicity
21 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

367 
WGUS53 KEAX 301338
FFWEAX
KSC091-103-209-MOC047-095-165-177-301730-
/O.NEW.KEAX.FF.W.0027.210630T1338Z-210630T1730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Kansas City/Pleasant Hill MO
838 AM CDT Wed Jun 30 2021

The National Weather Service in Pleasant Hill MO has issued a

* Flash Flood Warning for...
  Johnson KS County in east central Kansas...
  Southern Leavenworth County in northeastern Kansas...
  Wyandotte County in northeastern Kansas...
  Clay County in west central Missouri...
  Northern Jackson County in west central Missouri...
  Southeastern Platte County in west central Missouri...
  Ray County in west central Missouri...

* Until 1230 PM CDT.

* At 838 AM CDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1 and 2 inches of rain have fallen. Additional rainfall amounts of 
  1 to 2 inches are possible in the warned area. Flash flooding is 
  ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  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...
  Kansas City, Overland Park, Olathe, Independence, Shawnee, Blue 
  Springs, Lenexa, Leawood, Raytown, Liberty, Gladstone, Prairie 
  Village, Gardner, Lansing, Excelsior Springs, Merriam, Mission, 
  Smithville, Kearney and Bonner Springs.

This includes the following highways...
	Kansas Turnpike between mile markers 206 and 226.
	Interstate 435 between mile markers 0 and 26...and
	between mile markers 35 and 67...and
	between mile markers 77 and 83.
	Interstate 35 in Kansas between mile markers 214 and 235.
	Interstate 635 between mile markers 0 and 12.
	Interstate 29 between mile markers 0 and 13.
	Interstate 35 in Missouri between mile markers 0 and 31.
	Interstate 70 in Kansas between mile markers 410 and 423.
	Interstate 70 in Missouri between mile markers 0 and 16.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3905 9519 3918 9501 3942 9442 3952 9387
      3925 9376 3921 9376 3921 9386 3914 9396
      3914 9397 3915 9399 3920 9397 3919 9403
      3915 9402 3914 9410 3910 9411 3902 9443
      3875 9506 3898 9506 3895 9509 3896 9519

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

PP
1 follow-up statement
063 
WGUS73 KEAX 301722
FFSEAX

Flash Flood Statement
National Weather Service Kansas City/Pleasant Hill MO
1222 PM CDT Wed Jun 30 2021

KSC091-103-209-MOC047-095-165-177-301732-
/O.CAN.KEAX.FF.W.0027.000000T0000Z-210630T1730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Johnson KS KS-Leavenworth KS-Wyandotte KS-Clay MO-Jackson MO-
Platte MO-Ray MO-
1222 PM CDT Wed Jun 30 2021

...FLASH FLOOD WARNING FOR SOUTHERN LEAVENWORTH, WYANDOTTE, CLAY, 
NORTHERN JACKSON, SOUTHEASTERN PLATTE AND RAY COUNTIES HAS BEEN 
REPLACED WITH A FLOOD WARNING...

LAT...LON 3905 9519 3918 9501 3942 9442 3952 9387
      3925 9376 3921 9376 3921 9386 3914 9396
      3914 9397 3915 9399 3920 9397 3919 9403
      3915 9402 3914 9410 3910 9411 3902 9443
      3875 9506 3898 9506 3895 9509 3896 9519

$$

PP

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 30, 9:06 AM CDTRiver Flood WarningEAXBates59 hr
Jun 30, 10:28 AM CDTRiver Flood WarningEAXCarroll, Lafayette, Saline40 hr
Jun 30, 11:06 AM CDTRiver Flood WarningEAXJackson3 hr
Jun 30, 11:06 AM CDTRiver Flood WarningEAXClay, Ray9 hr
Jun 30, 12:04 PM CDTFlash Flood WarningEAXCass, Jackson, Johnson, Lafayette4 hr
Jun 30, 12:22 PM CDTAreal Flood WarningEAXClay, Jackson, Platte18 hr
Jun 30, 12:50 PM CDTRiver Flood WarningEAXLinn, Livingston34 hr
Jun 30, 2:12 PM CDTRiver Flood WarningEAXJackson6 hr
Jun 30, 2:33 PM CDTFlash Flood WarningEAXBates, Cass, Henry, Johnson, Pettis4 hr
Jun 30, 2:56 PM CDTSpecial Weather StatementEAXBates49 min
Jun 30, 3:54 PM CDTAreal Flood WarningEAXCass, Jackson, Johnson, Lafayette14 hr
Jun 30, 4:15 PM CDTRiver Flood WarningEAXJackson, Lafayette, Ray49 hr
Jun 30, 4:50 PM CDTFlash Flood WarningEAXAndrew, Daviess, DeKalb, Gentry, Grundy, Harrison and 5 more4 hr
Jun 30, 9:06 AM CDTRiver Flood WarningEAXMiami3 days
Jun 30, 9:06 AM CDTRiver Flood WarningEAXLinn4 days

Nearby

Flash Flood Warnings in Missouri, 2021Flash Flood Warnings in Kansas, 2021Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.