Alert archive / Illinois / Flash Flood Warnings in 2025

Flash Flood Warning 21, NWS St. Louis, MO

July 6, 2025Madison County, Saint Clair County, Illinois; City of Saint Louis, Missouri

NWS St. Louis, MO issued this flash flood warning at Jul 6, 2025, 4:17 PM CDT for Madison County, Saint Clair County, Illinois; City of Saint Louis, Missouri. It was in force for 3 hr. 6 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
Jul 6, 2025, 4:17 PM CDT (21:17 UTC)
Expired
Jul 6, 2025, 7:00 PM CDT
In force
3 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

Counties Madison County, IL, Saint Clair County, IL, City of Saint Louis, MO

The radar

The St Louis radar (KLSX), 56 km from the middle of the area, began a volume at 21:19 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

TimeReportWhereRemark
Jul 6, 5:00 PM CDTFLASH FLOOD1 Se Lebanon, ILvideo shows extensive standing water flooding along Madison Street including the parking lot of an Ace Hardware store.
Jul 6, 5:00 PM CDTFLASH FLOODLebanon, ILA total of 4.02 inches of rain was recorded. Water was several inches deep in the back yard and flooded into the basement.
Jul 6, 5:15 PM CDTRAIN 5.04Lebanon, ILWithin a 2.5 hour timeframe.
Jul 6, 5:59 PM CDTRAIN 1.9Swansea, IL
Jul 6, 6:00 PM CDTFLASH FLOOD1 Se Lebanon, ILCorrects time of the previous flash flood report from 1 SE Lebanon. video shows extensive standing water flooding along Madison Street including the parking lot of an Ace Hardware store.
Jul 6, 6:36 PM CDTRAIN 53 N Summerfield, IL

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

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.3 hours before the alert went out and 207 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 12:00Z on 2025-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 203 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, Lincoln, IL at 12:00Z on 2025-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 1 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
203 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
969 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
1 m²/s²
0-3 km storm-relative helicity
4 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

962 
WGUS53 KLSX 062117
FFWLSX
ILC119-163-MOC510-070000-
/O.NEW.KLSX.FF.W.0021.250706T2117Z-250707T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
417 PM CDT Sun Jul 6 2025

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Southern Madison County in southwestern Illinois...
  Northern Saint Clair County in southwestern Illinois...
  Northeastern Saint Louis City in east central Missouri...

* Until 700 PM CDT.

* At 417 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  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...
  St. Louis, Belleville, Granite City, O'Fallon, East St. Louis, 
  Collinsville, Fairview Heights, Cahokia, Swansea, Glen Carbon, 
  Shiloh, Troy, Maryville, Mascoutah, Pontoon Beach, Centreville, 
  Lebanon, Caseyville, Washington Park and Madison.

This includes the following State Parks...
	Horseshoe Lake State Park.

This includes Interstate 64 in Illinois between exits 9 and 27.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3871 9021 3873 9021 3875 9018 3874 8970
      3866 8970 3866 8971 3859 8971 3849 8970
      3855 9019 3860 9019 3861 9018 3864 9018
      3867 9019 3869 9020 3870 9021

FLASH FLOOD...RADAR INDICATED

$$

Kimble
2 follow-up statements
983 
WGUS73 KLSX 062215
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
515 PM CDT Sun Jul 6 2025

MOC510-062225-
/O.CAN.KLSX.FF.W.0021.000000T0000Z-250707T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Saint Louis City MO-
515 PM CDT Sun Jul 6 2025

...FLASH FLOOD WARNING IS CANCELLED FOR THE NORTHEASTERN SAINT LOUIS 
CITY...

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

&&

LAT...LON 3854 9011 3869 9006 3874 8970 3866 8970
      3866 8971 3854 8971 3849 8970

$$

ILC119-163-070000-
/O.CON.KLSX.FF.W.0021.000000T0000Z-250707T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Madison IL-Saint Clair IL-
515 PM CDT Sun Jul 6 2025

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING 
FOR SOUTHEASTERN MADISON AND NORTHEASTERN SAINT CLAIR COUNTIES IN 
SOUTHWESTERN ILLINOIS...

At 515 PM CDT, trained weather spotters flash flooding in Lebanon 
due to very heavy rainfall. Over 4 inches of rain has fallen. 
Although rain is coming to an end, it will take some time for flood 
waters to recede.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Trained spotters 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...
  Belleville, O'Fallon, East St. Louis, Collinsville, Fairview 
  Heights, Swansea, Shiloh, Troy, Maryville, Mascoutah, Pontoon 
  Beach, Centreville, Lebanon, Caseyville, Washington Park, New 
  Baden, Scott AFB, Alorton, St. Jacob and Summerfield.

This includes Interstate 64 in Illinois between exits 9 and 27.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3854 9011 3869 9006 3874 8970 3866 8970
      3866 8971 3854 8971 3849 8970

FLASH FLOOD...OBSERVED

$$

Kimble
620 
WGUS73 KLSX 062225
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
525 PM CDT Sun Jul 6 2025

ILC119-163-070000-
/O.CON.KLSX.FF.W.0021.000000T0000Z-250707T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Madison IL-Saint Clair IL-
525 PM CDT Sun Jul 6 2025

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING 
FOR SOUTHEASTERN MADISON AND NORTHEASTERN SAINT CLAIR COUNTIES IN 
SOUTHWESTERN ILLINOIS...

At 525 PM CDT, trained weather spotters reported flash flooding in 
Lebanon
due to very heavy rainfall. Over 4 inches of rain has fallen. 
Although rain is coming to an end, it will take some time for flood 
waters to recede.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Trained spotters 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...
  Belleville, O'Fallon, East St. Louis, Collinsville, Fairview 
  Heights, Swansea, Shiloh, Troy, Maryville, Mascoutah, Pontoon 
  Beach, Centreville, Lebanon, Caseyville, Washington Park, New 
  Baden, Scott AFB, Alorton, St. Jacob and Summerfield.

This includes Interstate 64 in Illinois between exits 9 and 27.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3854 9011 3869 9006 3874 8970 3866 8970
      3866 8971 3854 8971 3849 8970

FLASH FLOOD...OBSERVED

$$

Kimble

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 6, 4:04 PM CDTAreal Flood AdvisoryLSXMadison, Saint Clair13 min
Jul 6, 4:11 PM CDTSevere Thunderstorm WarningLSXMadison, Saint Clair49 min
Jul 6, 4:46 PM CDTSevere Thunderstorm WarningLSXClinton25 min
Jul 6, 5:21 PM CDTFlash Flood WarningLSXFayette3 hr
Jul 6, 2:47 PM CDTAreal Flood AdvisoryLSXBoone2 hr
Jul 6, 3:20 PM CDTSevere Thunderstorm WarningLSXSaint Charles40 min
Jul 6, 3:54 PM CDTSevere Thunderstorm WarningLSXBoone19 min

Nearby

Flash Flood Warnings in Illinois, 2025Flash Flood Warnings in Missouri, 2025Every flash flood warning in 2025

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.