Alert archive / Illinois / Flash Flood Warnings in 2021

Flash Flood Warning 37, NWS St. Louis, MO

August 12, 2021Bond County, Madison County, Illinois

NWS St. Louis, MO issued this flash flood warning at Aug 12, 2021, 7:40 PM CDT for Bond County, Madison County, Illinois. 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
Aug 12, 2021, 7:40 PM CDT (00:40 UTC)
Expired
Aug 12, 2021, 11:45 PM CDT
In force
4 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

Counties Bond County, IL, Madison County, IL

The radar

The St Louis radar (KLSX), 88 km from the middle of the area, began a volume at 00:44 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

Lincoln, IL (KILX), launched 00:00Z, 0.7 hours before the alert went out and 166 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, Lincoln, IL at 00:00Z on 2021-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Lincoln, IL at 00:00Z on 2021-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1699 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

113 
WGUS53 KLSX 130040
FFWLSX
ILC005-119-130445-
/O.NEW.KLSX.FF.W.0037.210813T0040Z-210813T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
740 PM CDT Thu Aug 12 2021

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  West Central Bond County in south central Illinois...
  Northeastern Madison County in southwestern Illinois...

* Until 1145 PM CDT.

* At 740 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 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...
  Edwardsville, Glen Carbon, Staunton, Worden, Livingston, Alhambra, 
  Carpenter, Prairietown, Hamel, Grantfork, New Douglas, Williamson, 
  Old Ripley, Kaufman and Fruit.

This includes the following highways...
	Interstate 55 in Illinois between exits 23 and 37.

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 3900 8996 3900 8964 3898 8964 3895 8948
      3890 8947 3885 8960 3877 8998

FLASH FLOOD...RADAR INDICATED

$$

Gosselin
2 follow-up statements
072 
WGUS73 KLSX 130202
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
902 PM CDT Thu Aug 12 2021

ILC005-119-130445-
/O.CON.KLSX.FF.W.0037.000000T0000Z-210813T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bond IL-Madison IL-
902 PM CDT Thu Aug 12 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1145 PM CDT THIS 
EVENING FOR WEST CENTRAL BOND COUNTY IN SOUTH CENTRAL ILLINOIS AND 
NORTHEASTERN MADISON COUNTY IN SOUTHWESTERN ILLINOIS...

At 902 PM CDT, local law enforcement reported flooding on I-55 at 
Route 140 near Hamel, Illinois. Between 2 and 3 inches of rain have 
fallen. Between 2 and 4 inches of rain have fallen. Flash flooding 
is ongoing or expected to begin shortly.

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...
  Edwardsville, Glen Carbon, Staunton, Worden, Livingston, Alhambra, 
  Carpenter, Prairietown, Hamel, Grantfork, New Douglas, Williamson, 
  Old Ripley, Kaufman and Fruit.

This includes the following highways...
	Interstate 55 in Illinois between exits 23 and 37.

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 3900 8996 3900 8964 3898 8964 3895 8948
      3890 8947 3885 8960 3877 8998

FLASH FLOOD...OBSERVED

$$

Gosselin
545 
WGUS73 KLSX 130437
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
1137 PM CDT Thu Aug 12 2021

ILC005-119-130447-
/O.EXP.KLSX.FF.W.0037.000000T0000Z-210813T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bond IL-Madison IL-
1137 PM CDT Thu Aug 12 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 1145 PM CDT THIS EVENING FOR 
WEST CENTRAL BOND COUNTY IN SOUTH CENTRAL ILLINOIS AND NORTHEASTERN 
MADISON COUNTY IN SOUTHWESTERN ILLINOIS...

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

LAT...LON 3900 8996 3900 8964 3898 8964 3895 8948
      3890 8947 3885 8960 3877 8998

$$

Glass

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 7:14 PM CDTSevere Thunderstorm Warning Considerable damage threatLSXClinton, Madison, Monroe, Randolph, Saint Clair, Washington61 min

Nearby

Flash Flood Warnings in Illinois, 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.