Alert archive / Missouri / Flash Flood Warnings in 2025

Flash Flood Warning 2, NWS St. Louis, MO

April 4, 2025Saint Charles County, Warren County, Missouri

NWS St. Louis, MO issued this flash flood warning at Apr 4, 2025, 3:42 PM CDT for Saint Charles County, Warren County, Missouri. It was in force for 4 hr. 8 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
Apr 4, 2025, 3:42 PM CDT (20:42 UTC)
Expired
Apr 4, 2025, 8:05 PM CDT
In force
4 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

Counties Saint Charles County, MO, Warren County, MO

The radar

The St Louis radar (KLSX), 23 km from the middle of the area, began a volume at 20:42 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
Apr 4, 4:05 PM CDTRAIN 1.321 Sw Warrenton, MO
Apr 4, 4:09 PM CDTFLASH FLOOD2 Ne Wright City, MOHighway J at BMC Stone quarry flooded. This spot typically floods when heavy rain falls.
Apr 4, 4:09 PM CDTFLASH FLOOD2 Nnw Marthasville, MOHighway O at Walnut Crest flooded. This spot typically floods when heavy rain falls.
Apr 4, 4:09 PM CDTFLASH FLOOD3 Ssw Foristell, MOSchreckengast Road at Cedar Lake Cellars flooded. This spot typically floods when heavy rain falls.
Apr 4, 4:09 PM CDTFLASH FLOOD5 Se Truesdale, MOHighway F at S Stracks Church Road flooded. This spot typically floods when heavy rain falls.
Apr 4, 4:41 PM CDTFLASH FLOOD3 N Saint Paul, MOA couple of calls into EOC about heavy flooding on MO-79 north of Dalbow Road. Extent of actual flooding is unknown.
Apr 4, 5:48 PM CDTFLOOD1 S O'Fallon, MOReport from mPING: River/Creek overflowing; Cropland/Yard/Basement Flooding.
Apr 4, 7:20 PM CDTRAIN 3.021 E Saint Peters, MOStill rain to come.

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, 8.7 hours before the alert went out and 253 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 2025-04-04Temperature 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 12:00Z on 2025-04-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 30 square meters per square second.1939587897117Sfc1 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
1306 m above ground
0-6 km bulk shear
78 kt
0-1 km storm-relative helicity
30 m²/s²
0-3 km storm-relative helicity
211 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

487 
WGUS53 KLSX 042042
FFWLSX
MOC183-219-042345-
/O.NEW.KLSX.FF.W.0002.250404T2042Z-250404T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
342 PM CDT Fri Apr 4 2025

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Saint Charles County in east central Missouri...
  Warren County in east central Missouri...

* Until 645 PM CDT.

* At 342 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 3 inches are 
  possible in 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...
  O'Fallon, St. Peters, Chesterfield, Wildwood, Wentzville, Lake St. 
  Louis, Dardenne Prairie, Warrenton, Weldon Spring, Wright City, 
  Cottleville, St. Paul, Marthasville, Truesdale, Innsbrook, New 
  Melle, Josephville, Augusta, Weldon Spring Heights and Dutzow.

This includes Interstate 70 in Missouri between exits 193 and 224.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3862 9122 3865 9123 3871 9132 3871 9140
      3888 9111 3887 9096 3889 9095 3888 9082
      3892 9078 3893 9073 3892 9073 3891 9072
      3893 9067 3887 9059 3868 9058 3869 9066
      3861 9076 3854 9092 3861 9106 3860 9113

FLASH FLOOD...RADAR INDICATED

$$

Walsh
3 follow-up statements
064 
WGUS53 KLSX 042301
FFWLSX
MOC183-219-050045-
/O.EXT.KLSX.FF.W.0002.000000T0000Z-250405T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
601 PM CDT Fri Apr 4 2025

The National Weather Service in St Louis has extended the

* Flash Flood Warning for...
  Saint Charles County in east central Missouri...
  Warren County in east central Missouri...

* Until 745 PM CDT.

* At 601 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. Additional rainfall amounts up to 1 inch are possible 
  in 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...
  O'Fallon, St. Peters, Chesterfield, Wildwood, Wentzville, Lake St. 
  Louis, Dardenne Prairie, Warrenton, Weldon Spring, Wright City, 
  Cottleville, St. Paul, Marthasville, Truesdale, Innsbrook, New 
  Melle, Josephville, Augusta, Weldon Spring Heights and Dutzow.

This includes Interstate 70 in Missouri between exits 193 and 224.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3862 9122 3865 9123 3871 9132 3871 9140
      3888 9111 3887 9096 3889 9095 3888 9082
      3892 9078 3893 9073 3892 9073 3891 9072
      3893 9067 3887 9059 3868 9058 3869 9066
      3861 9076 3854 9092 3861 9106 3860 9113

FLASH FLOOD...RADAR INDICATED

$$

Walsh
990 
WGUS53 KLSX 042359
FFWLSX
MOC183-219-050145-
/O.EXT.KLSX.FF.W.0002.000000T0000Z-250405T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
659 PM CDT Fri Apr 4 2025

The National Weather Service in St Louis has extended the

* Flash Flood Warning for...
  Saint Charles County in east central Missouri...
  Warren County in east central Missouri...

* Until 845 PM CDT.

* At 659 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. Additional rainfall amounts up to 1 inch are possible 
  in 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...
  O'Fallon, St. Peters, Chesterfield, Wildwood, Wentzville, Lake St. 
  Louis, Dardenne Prairie, Warrenton, Weldon Spring, Wright City, 
  Cottleville, St. Paul, Marthasville, Truesdale, Innsbrook, New 
  Melle, Josephville, Augusta, Weldon Spring Heights and Dutzow.

This includes Interstate 70 in Missouri between exits 193 and 224.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3862 9122 3865 9123 3871 9132 3871 9140
      3888 9111 3887 9096 3889 9095 3888 9082
      3892 9078 3893 9073 3892 9073 3891 9072
      3893 9067 3887 9059 3868 9058 3869 9066
      3861 9076 3854 9092 3861 9106 3860 9113

FLASH FLOOD...RADAR INDICATED

$$

Walsh
607 
WGUS73 KLSX 050105
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
805 PM CDT Fri Apr 4 2025

MOC183-219-050115-
/O.CAN.KLSX.FF.W.0002.000000T0000Z-250405T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Saint Charles MO-Warren MO-
805 PM CDT Fri Apr 4 2025

...FLASH FLOOD WARNING IS CANCELLED FOR SAINT CHARLES AND WARREN 
COUNTIES...

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

A Flood Watch remains in effect until 100 AM CDT Sunday for portions 
of Illinois and Missouri.

&&

LAT...LON 3862 9122 3865 9123 3871 9132 3871 9140
      3888 9111 3887 9096 3889 9095 3888 9082
      3892 9078 3893 9073 3892 9073 3891 9072
      3893 9067 3887 9059 3868 9058 3869 9066
      3861 9076 3854 9092 3861 9106 3860 9113

$$

Walsh

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 3, 8:05 PM CDTRiver Flood WarningLSXSaint Charles3 days
Apr 4, 2:25 PM CDTFlash Flood WarningLSXFranklin, Gasconade, Osage3 hr
Apr 4, 2:48 PM CDTAreal Flood AdvisoryLSXSaint Charles, Warren54 min
Apr 4, 3:36 PM CDTAreal Flood AdvisoryLSXFranklin, Saint Charles, Saint Louis, City of Saint Louis2 hr
Apr 4, 3:37 PM CDTAreal Flood AdvisoryLSXLincoln, Saint Charles3 hr
Apr 4, 4:18 PM CDTFlash Flood WarningLSXFranklin, Saint Louis4 hr
Apr 4, 4:51 PM CDTRiver Flood WarningLSXOsage27 hr
Apr 4, 5:33 PM CDTAreal Flood AdvisoryLSXIron, Reynolds51 min
Apr 4, 5:45 PM CDTFlash Flood WarningLSXFranklin, Saint Charles, Saint Louis, City of Saint Louis3 hr
Apr 4, 5:49 PM CDTAreal Flood AdvisoryLSXSaint Francois, Washington38 min
Apr 4, 6:08 PM CDTAreal Flood AdvisoryLSXSainte Genevieve, Saint Francois20 min
Apr 4, 6:18 PM CDTAreal Flood AdvisoryLSXCity of Saint Louis3 hr
Apr 4, 6:24 PM CDTFlash Flood WarningLSXIron, Madison, Reynolds5 hr
Apr 4, 6:26 PM CDTFlash Flood WarningLSXMadison, Saint Francois5 hr
Apr 4, 6:27 PM CDTFlash Flood WarningLSXSaint Francois, Washington5 hr
Apr 4, 6:28 PM CDTFlash Flood WarningLSXSainte Genevieve, Saint Francois7 hr
Apr 4, 6:51 PM CDTFlash Flood WarningLSXJefferson7 hr

Nearby

Flash 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.