Alert archive / Illinois / Flash Flood Warnings in 2021

Flash Flood Warning 43, NWS St. Louis, MO

October 24, 2021Adams County, Brown County, Illinois

NWS St. Louis, MO issued this flash flood warning at Oct 24, 2021, 4:03 PM CDT for Adams County, Brown County, Illinois. It was in force for 4 hr. 1 report 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: Oct 24, 2021, 4:03 PM CDT (21:03 UTC)
Expired: Oct 24, 2021, 8:15 PM CDT
In force: 4 hr
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Flood severity: None

Counties Adams County, IL, Brown County, IL

The radar

The Lincoln radar (KILX), 139 km from the middle of the area, began a volume at 21:03 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
Oct 24, 5:57 PM CDT	FLASH FLOOD	Clayton, IL	MULTIPLE ROADS WASHED OUT IN TOWN OF CLAYTON INCLUDING N 1353RD LANE.

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

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 9.1 hours before the alert went out and 187 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 972 m above ground
0-6 km bulk shear: 61 kt
0-1 km storm-relative helicity: 120 m²/s²
0-3 km storm-relative helicity: 162 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

038 
WGUS53 KLSX 242103
FFWLSX
ILC001-009-250115-
/O.NEW.KLSX.FF.W.0043.211024T2103Z-211025T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
403 PM CDT Sun Oct 24 2021

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Southern Adams County in west central Illinois...
  Northern Brown County in west central Illinois...

* Until 815 PM CDT.

* At 403 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. The expected rainfall rate is 1 
  to 2 inches in 1 hour. 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.

  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...
  Quincy, Quincy Regional Airport, Mount Sterling, Camp Point, 
  Payson, Clayton, Golden, Fall Creek, Beverly, Buckhorn, Adams, 
  Kingston, Burton, Liberty, Richfield, Plainville, Mound Station, 
  Columbus, Ripley and Kellerville.

This includes the following State Parks...
	Siloam Springs State Park.

This includes the following highways...
	Interstate 72 near exit 4.
	Interstate 172 between exits 2 and 14.

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 4001 9113 4019 9092 4010 9091 4010 9070
      4009 9071 4008 9067 4005 9067 4002 9063
      4003 9061 4002 9062 4000 9060 3988 9092
      3976 9092 3976 9136 3980 9137 3984 9143
      3988 9145 3992 9142

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

Gosselin

2 follow-up statements

927 
WGUS73 KLSX 242301
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
601 PM CDT Sun Oct 24 2021

ILC001-009-250115-
/O.CON.KLSX.FF.W.0043.000000T0000Z-211025T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Adams IL-Brown IL-
601 PM CDT Sun Oct 24 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM CDT THIS 
EVENING FOR SOUTHERN ADAMS AND NORTHERN BROWN COUNTIES...

At 601 PM CDT, local law enforcement reported multiple roads washed 
out in Clayton and Concord township. Flash flooding is ongoing.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Law enforcement reported.

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...
  Quincy, Quincy Regional Airport, Mount Sterling, Camp Point, 
  Payson, Clayton, Golden, Fall Creek, Beverly, Buckhorn, Adams, 
  Kingston, Burton, Liberty, Richfield, Plainville, Mound Station, 
  Columbus, Ripley and Kellerville.

This includes the following State Parks...
	Siloam Springs State Park.

This includes the following highways...
	Interstate 172 between exits 2 and 14.

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 4001 9113 4019 9092 4010 9091 4010 9070
      4009 9071 4008 9067 4005 9067 4002 9063
      4003 9061 4002 9062 4000 9060 3988 9092
      3976 9092 3976 9136 3980 9137 3984 9143
      3988 9145 3992 9142

FLASH FLOOD...OBSERVED

$$

Gosselin

882 
WGUS73 KLSX 250110
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
810 PM CDT Sun Oct 24 2021

ILC001-009-250120-
/O.EXP.KLSX.FF.W.0043.000000T0000Z-211025T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Adams IL-Brown IL-
810 PM CDT Sun Oct 24 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 815 PM CDT THIS EVENING FOR 
SOUTHERN ADAMS AND NORTHERN BROWN COUNTIES...

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

LAT...LON 4001 9113 4019 9092 4010 9091 4010 9070
      4009 9071 4008 9067 4005 9067 4002 9063
      4003 9061 4002 9062 4000 9060 3988 9092
      3976 9092 3976 9136 3980 9137 3984 9143
      3988 9145 3992 9142

$$

Gosselin

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 24, 4:17 AM CDT	Areal Flood Advisory	LSX	Adams, Brown	6 hr
Oct 24, 4:58 AM CDT	Flash Flood Warning	LSX	Adams	2 hr
Oct 24, 4:49 PM CDT	Severe Thunderstorm Warning	LSX	Pike	41 min
Oct 24, 5:14 PM CDT	Flash Flood Warning	LSX	Brown, Pike	4 hr
Oct 24, 5:17 PM CDT	Tornado Warning	LSX	Calhoun, Greene, Pike	43 min

Nearby

Flash Flood Warnings in Illinois, 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.