Alert archive / Kansas / Flash Flood Warnings in 2021

Flash Flood Warning 19, NWS Topeka, KS

June 30, 2021Coffey County, Lyon County, Kansas

NWS Topeka, KS issued this flash flood warning at Jun 30, 2021, 11:39 AM CDT for Coffey County, Lyon County, Kansas. It was in force for 2 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, 11:39 AM CDT (16:39 UTC)
Expired
Jun 30, 2021, 2:00 PM CDT
In force
2 hr
Issued by
NWS Topeka, KS
Area
Storm-based polygon
Flood severity
None

Counties Coffey County, KS, Lyon County, KS

The radar

The Topeka radar (KTWX), 93 km from the middle of the area, began a volume at 16:43 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, 4.7 hours before the alert went out and 95 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.

108 
WGUS53 KTOP 301639
FFWTOP
KSC031-111-301900-
/O.NEW.KTOP.FF.W.0019.210630T1639Z-210630T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Topeka KS
1139 AM CDT Wed Jun 30 2021

The National Weather Service in Topeka has issued a

* Flash Flood Warning for...
  Southwestern Coffey County in east central Kansas...
  Southeastern Lyon County in east central Kansas...

* Until 200 PM CDT.

* At 1138 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Up to 1.5 inches of rain have 
  fallen. Additional rainfall amounts up 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.

  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...
  Burlington, Gridley and John Redmond Reservoir.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3817 9614 3829 9613 3830 9576 3810 9575
      3809 9596 3817 9596

FLASH FLOOD...RADAR INDICATED

$$

53
1 follow-up statement
671 
WGUS73 KTOP 301855
FFSTOP

Flash Flood Statement
National Weather Service Topeka KS
155 PM CDT Wed Jun 30 2021

KSC031-111-301905-
/O.EXP.KTOP.FF.W.0019.000000T0000Z-210630T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coffey KS-Lyon KS-
155 PM CDT Wed Jun 30 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 2 PM CDT THIS AFTERNOON FOR 
SOUTHWESTERN COFFEY AND SOUTHEASTERN LYON COUNTIES...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

A Flash Flood Watch remains in effect until 700 AM CDT Thursday for 
portions of east central Kansas and northeast Kansas.

LAT...LON 3817 9614 3829 9613 3830 9576 3810 9575
      3809 9596 3817 9596

$$

53

The office that day

Everything else NWS Topeka, KS issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 30, 5:04 AM CDTAreal Flood AdvisoryTOPLyon, Morris116 min
Jun 30, 6:30 AM CDTAreal Flood AdvisoryTOPOsage, Shawnee, Wabaunsee3 hr
Jun 30, 7:38 AM CDTAreal Flood AdvisoryTOPDouglas, Franklin, Osage2 hr
Jun 30, 8:37 AM CDTFlash Flood WarningTOPDouglas2 hr
Jun 30, 12:36 PM CDTAreal Flood AdvisoryTOPAnderson, Coffey, Franklin, Osage4 hr
Jun 30, 2:19 PM CDTAreal Flood AdvisoryTOPDouglas, Jefferson, Morris, Osage, Shawnee, Wabaunsee3 hr
Jun 30, 3:31 PM CDTRiver Flood WarningTOPFranklin, Osage23 hr
Jun 30, 6:35 PM CDTAreal Flood WarningTOPAnderson, Coffey3 hr

Nearby

Flash 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.