Alert archive / Missouri / Flood Watches in 2025

Flood Watch 2, NWS St. Louis, MO

April 17, 202523 counties in Missouri; 14 counties in Illinois

NWS St. Louis, MO issued this flood watch at Apr 17, 2025, 1:54 PM CDT for 23 counties in Missouri; 14 counties in Illinois. It took effect at Apr 18, 2025, 7:00 PM CDT. It was in force for 52 hr.

The area

The counties it named.

The facts

Issued
Apr 17, 2025, 1:54 PM CDT (18:54 UTC)
In effect from
Apr 18, 2025, 7:00 PM CDT
Expired
Apr 20, 2025, 10:59 PM CDT
In force
52 hr
Issued by
NWS St. Louis, MO
Flood severity
None
All 37 counties

Bond County, IL, Calhoun County, IL, Clinton County, IL, Fayette County, IL, Greene County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Lincoln County, MO, Madison County, MO, Moniteau County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Warren County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 15 km from the middle of the area, began a volume at 18:57 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 12:00Z, 6.9 hours before the alert went out and 248 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 2025-04-17Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 12:00Z on 2025-04-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 256 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
2214 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
256 m²/s²
0-3 km storm-relative helicity
284 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

641 
WGUS63 KLSX 171854
FFALSX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service St Louis MO
154 PM CDT Thu Apr 17 2025

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-181000-
/O.NEW.KLSX.FA.A.0002.250419T0000Z-250421T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-Madison
IL-Saint Clair IL-Monroe IL-Pike MO-Boone MO-Audrain MO-Moniteau
MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-Lincoln MO-
Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-Saint Louis
MO-Saint Louis City MO-Jefferson MO-Crawford MO-Washington MO-
Saint Francois MO-Sainte Genevieve MO-Iron MO-Madison MO-Reynolds
MO-
Including the cities of Bowling Green, Cahokia, Union, Salem,
Saint Louis, Chester, Centralia, Litchfield, Saint Charles,
Jefferson City, Sparta, Fulton, Columbia, Washington, Farmington,
Vandalia, Sullivan, Mexico, Belleville, Alton, and Edwardsville
154 PM CDT Thu Apr 17 2025

...FLOOD WATCH IN EFFECT FROM FRIDAY EVENING THROUGH SUNDAY 
EVENING...

* WHAT...Flash flooding caused by excessive rainfall is possible.

* WHERE...Portions of Illinois, including the following areas, Bond 
  IL, Calhoun IL, Clinton IL, Fayette IL, Greene IL, Jersey IL, 
  Macoupin IL, Madison IL, Marion IL, Monroe IL, Montgomery IL, 
  Randolph IL, Saint Clair IL and Washington IL and Missouri, 
  including the following areas, Audrain MO, Boone MO, Callaway MO, 
  Cole MO, Crawford MO, Franklin MO, Gasconade MO, Iron MO, 
  Jefferson MO, Lincoln MO, Madison MO, Moniteau MO, Montgomery MO, 
  Osage MO, Pike MO, Reynolds MO, Saint Charles MO, Saint Francois 
  MO, Saint Louis City MO, Saint Louis MO, Sainte Genevieve MO, 
  Warren MO and Washington MO.

* WHEN...From Friday evening through Sunday evening.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Several rounds of showers and thunderstorms are likely Friday
    night through Sunday. Total rainfall amounts of 2-4 inches
    are likely across most of the area with localized amounts to
    6 inches. Highest rainfall amounts are expected along and
    just north of the Interstate 44 corridor.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

BSH
11 follow-up statements
294 
WGUS63 KLSX 180829
FFALSX

Flood Watch
National Weather Service St Louis MO
329 AM CDT Fri Apr 18 2025

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-182330-
/O.CON.KLSX.FA.A.0002.250419T0000Z-250421T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-Madison
IL-Saint Clair IL-Monroe IL-Pike MO-Boone MO-Audrain MO-Moniteau
MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-Lincoln MO-
Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-Saint Louis
MO-Saint Louis City MO-Jefferson MO-Crawford MO-Washington MO-
Saint Francois MO-Sainte Genevieve MO-Iron MO-Madison MO-Reynolds
MO-
Including the cities of Sparta, Saint Louis, Mexico, Farmington,
Saint Charles, Columbia, Edwardsville, Jefferson City,
Washington, Salem, Union, Centralia, Chester, Litchfield,
Cahokia, Bowling Green, Vandalia, Fulton, Belleville, Sullivan,
and Alton
329 AM CDT Fri Apr 18 2025

...FLOOD WATCH REMAINS IN EFFECT FROM THIS EVENING THROUGH SUNDAY 
EVENING...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...Portions of Illinois, including the following areas, Bond 
  IL, Calhoun IL, Clinton IL, Fayette IL, Greene IL, Jersey IL, 
  Macoupin IL, Madison IL, Marion IL, Monroe IL, Montgomery IL, 
  Randolph IL, Saint Clair IL and Washington IL and Missouri, 
  including the following areas, Audrain MO, Boone MO, Callaway MO, 
  Cole MO, Crawford MO, Franklin MO, Gasconade MO, Iron MO, 
  Jefferson MO, Lincoln MO, Madison MO, Moniteau MO, Montgomery MO, 
  Osage MO, Pike MO, Reynolds MO, Saint Charles MO, Saint Francois 
  MO, Saint Louis City MO, Saint Louis MO, Sainte Genevieve MO, 
  Warren MO and Washington MO.

* WHEN...From this evening through Sunday evening.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Several rounds of showers and thunderstorms are likely Friday
    night through Sunday. Rainfall totals of 2-4 inches are
    likely across much of the region with localized amounts up to
    5 inches. Highest rainfall totals are expected along and
    north of the I-44 corridor.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Maples
748 
WGUS63 KLSX 181848
FFALSX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service St Louis MO
148 PM CDT Fri Apr 18 2025

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-191000-
/O.EXT.KLSX.FA.A.0002.250419T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-Madison
IL-Saint Clair IL-Monroe IL-Pike MO-Boone MO-Audrain MO-Moniteau
MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-Lincoln MO-
Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-Saint Louis
MO-Saint Louis City MO-Jefferson MO-Crawford MO-Washington MO-
Saint Francois MO-Sainte Genevieve MO-Iron MO-Madison MO-Reynolds
MO-
Including the cities of Belleville, Sparta, Cahokia, Alton,
Farmington, Saint Louis, Edwardsville, Litchfield, Sullivan,
Washington, Mexico, Vandalia, Columbia, Union, Saint Charles,
Bowling Green, Fulton, Centralia, Jefferson City, Salem, and
Chester
148 PM CDT Fri Apr 18 2025

...FLOOD WATCH NOW IN EFFECT FROM 7 PM CDT THIS EVENING THROUGH LATE 
SUNDAY NIGHT...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...Portions of Illinois, including the following areas, Bond 
  IL, Calhoun IL, Clinton IL, Fayette IL, Greene IL, Jersey IL, 
  Macoupin IL, Madison IL, Marion IL, Monroe IL, Montgomery IL, 
  Randolph IL, Saint Clair IL and Washington IL and Missouri, 
  including the following areas, Audrain MO, Boone MO, Callaway MO, 
  Cole MO, Crawford MO, Franklin MO, Gasconade MO, Iron MO, 
  Jefferson MO, Lincoln MO, Madison MO, Moniteau MO, Montgomery MO, 
  Osage MO, Pike MO, Reynolds MO, Saint Charles MO, Saint Francois 
  MO, Saint Louis City MO, Saint Louis MO, Sainte Genevieve MO, 
  Warren MO and Washington MO.

* WHEN...From 7 PM CDT this evening through late Sunday night.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Several rounds of showers and thunderstorms are likely Friday
    night through Sunday. Rainfall totals of 2-4 inches are
    likely across much of the region with localized amounts up to
    5 inches. Highest rainfall totals are expected along and
    north of the I-44 corridor.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Gosselin
037 
WGUS63 KLSX 190837
FFALSX

Flood Watch
National Weather Service St Louis MO
337 AM CDT Sat Apr 19 2025

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-192345-
/O.CON.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-Madison
IL-Saint Clair IL-Monroe IL-Pike MO-Boone MO-Audrain MO-Moniteau
MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-Lincoln MO-
Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-Saint Louis
MO-Saint Louis City MO-Jefferson MO-Crawford MO-Washington MO-
Saint Francois MO-Sainte Genevieve MO-Iron MO-Madison MO-Reynolds
MO-
Including the cities of Litchfield, Vandalia, Union, Sparta,
Bowling Green, Fulton, Chester, Cahokia, Salem, Alton, Centralia,
Saint Charles, Sullivan, Belleville, Columbia, Saint Louis,
Washington, Mexico, Jefferson City, Farmington, and Edwardsville
337 AM CDT Sat Apr 19 2025

...FLOOD WATCH REMAINS IN EFFECT THROUGH LATE SUNDAY NIGHT...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...Portions of Illinois, including the following areas, Bond 
  IL, Calhoun IL, Clinton IL, Fayette IL, Greene IL, Jersey IL, 
  Macoupin IL, Madison IL, Marion IL, Monroe IL, Montgomery IL, 
  Randolph IL, Saint Clair IL and Washington IL and Missouri, 
  including the following areas, Audrain MO, Boone MO, Callaway MO, 
  Cole MO, Crawford MO, Franklin MO, Gasconade MO, Iron MO, 
  Jefferson MO, Lincoln MO, Madison MO, Moniteau MO, Montgomery MO, 
  Osage MO, Pike MO, Reynolds MO, Saint Charles MO, Saint Francois 
  MO, Saint Louis City MO, Saint Louis MO, Sainte Genevieve MO, 
  Warren MO and Washington MO.

* WHEN...Through late Sunday night.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Additional rounds of showers and thunderstorms are likely
    today through Sunday. Rainfall totals of 2-4 inches are
    expected across much of the region with localized amounts
    around 5 inches. Highest rainfall totals are expected along
    and north of the I-44 corridor.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Maples
207 
WGUS63 KLSX 191927
FFALSX

Flood Watch
National Weather Service St Louis MO
227 PM CDT Sat Apr 19 2025

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-201030-
/O.CON.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-Madison
IL-Saint Clair IL-Monroe IL-Pike MO-Boone MO-Audrain MO-Moniteau
MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-Lincoln MO-
Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-Saint Louis
MO-Saint Louis City MO-Jefferson MO-Crawford MO-Washington MO-
Saint Francois MO-Sainte Genevieve MO-Iron MO-Madison MO-Reynolds
MO-
Including the cities of Litchfield, Salem, Chester, Union,
Sparta, Vandalia, Columbia, Fulton, Saint Charles, Saint Louis,
Jefferson City, Mexico, Edwardsville, Farmington, Cahokia,
Centralia, Sullivan, Alton, Bowling Green, Washington, and
Belleville
227 PM CDT Sat Apr 19 2025

...FLOOD WATCH REMAINS IN EFFECT THROUGH LATE SUNDAY NIGHT...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...Portions of Illinois, including the following areas, Bond 
  IL, Calhoun IL, Clinton IL, Fayette IL, Greene IL, Jersey IL, 
  Macoupin IL, Madison IL, Marion IL, Monroe IL, Montgomery IL, 
  Randolph IL, Saint Clair IL and Washington IL and Missouri, 
  including the following areas, Audrain MO, Boone MO, Callaway MO, 
  Cole MO, Crawford MO, Franklin MO, Gasconade MO, Iron MO, 
  Jefferson MO, Lincoln MO, Madison MO, Moniteau MO, Montgomery MO, 
  Osage MO, Pike MO, Reynolds MO, Saint Charles MO, Saint Francois 
  MO, Saint Louis City MO, Saint Louis MO, Sainte Genevieve MO, 
  Warren MO and Washington MO.

* WHEN...Through late Sunday night.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Additional rounds of showers and thunderstorms are likely
    tonight through Sunday evening. Additional rainfall amounts
    of 1-2 inches are expected across much of the region.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Gosselin
990 
WGUS63 KLSX 200709
FFALSX

Flood Watch
National Weather Service St Louis MO
209 AM CDT Sun Apr 20 2025

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-202215-
/O.CON.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-Madison
IL-Saint Clair IL-Monroe IL-Pike MO-Boone MO-Audrain MO-Moniteau
MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-Lincoln MO-
Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-Saint Louis
MO-Saint Louis City MO-Jefferson MO-Crawford MO-Washington MO-
Saint Francois MO-Sainte Genevieve MO-Iron MO-Madison MO-Reynolds
MO-
Including the cities of Belleville, Centralia, Washington, Saint
Louis, Saint Charles, Chester, Jefferson City, Sparta,
Farmington, Bowling Green, Litchfield, Union, Edwardsville,
Sullivan, Vandalia, Mexico, Columbia, Salem, Alton, Cahokia, and
Fulton
209 AM CDT Sun Apr 20 2025

...FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...Portions of Illinois, including the following areas, Bond 
  IL, Calhoun IL, Clinton IL, Fayette IL, Greene IL, Jersey IL, 
  Macoupin IL, Madison IL, Marion IL, Monroe IL, Montgomery IL, 
  Randolph IL, Saint Clair IL and Washington IL and Missouri, 
  including the following areas, Audrain MO, Boone MO, Callaway MO, 
  Cole MO, Crawford MO, Franklin MO, Gasconade MO, Iron MO, 
  Jefferson MO, Lincoln MO, Madison MO, Moniteau MO, Montgomery MO, 
  Osage MO, Pike MO, Reynolds MO, Saint Charles MO, Saint Francois 
  MO, Saint Louis City MO, Saint Louis MO, Sainte Genevieve MO, 
  Warren MO and Washington MO.

* WHEN...Through late tonight.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Showers and thunderstorms are expected through late this
    evening. Additional rainfall amounts of 1-2 inches are
    favored. Locally higher amounts are possible in strong
    thunderstorms late this afternoon and evening.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Maples
467 
WGUS63 KLSX 202012
FFALSX

Flood Watch
National Weather Service St Louis MO
312 PM CDT Sun Apr 20 2025

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-041-042-047>052-
059>065-072>075-084-085-099-210600-
/O.CON.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-Madison
IL-Saint Clair IL-Monroe IL-Pike MO-Boone MO-Audrain MO-Moniteau
MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-Lincoln MO-
Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-Saint Louis
MO-Saint Louis City MO-Jefferson MO-Crawford MO-Washington MO-
Saint Francois MO-Sainte Genevieve MO-Iron MO-Madison MO-Reynolds
MO-
Including the cities of Vandalia, Saint Charles, Union, Fulton,
Sparta, Washington, Centralia, Jefferson City, Sullivan, Saint
Louis, Farmington, Columbia, Mexico, Salem, Bowling Green,
Chester, Edwardsville, Belleville, Cahokia, Alton, and Litchfield
312 PM CDT Sun Apr 20 2025

...FLOOD WATCH REMAINS IN EFFECT UNTIL 1 AM CDT MONDAY...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...Portions of Illinois, including the following areas, Bond 
  IL, Calhoun IL, Clinton IL, Fayette IL, Greene IL, Jersey IL, 
  Macoupin IL, Madison IL, Marion IL, Monroe IL, Montgomery IL, 
  Randolph IL, Saint Clair IL and Washington IL and Missouri, 
  including the following areas, Audrain MO, Boone MO, Callaway MO, 
  Cole MO, Crawford MO, Franklin MO, Gasconade MO, Iron MO, 
  Jefferson MO, Lincoln MO, Madison MO, Moniteau MO, Montgomery MO, 
  Osage MO, Pike MO, Reynolds MO, Saint Charles MO, Saint Francois 
  MO, Saint Louis City MO, Saint Louis MO, Sainte Genevieve MO, 
  Warren MO and Washington MO.

* WHEN...Until 1 AM CDT Monday.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Showers and thunderstorms are expected through late this
    evening. Additional rainfall amounts of 1-2 inches are
    favored. Locally higher amounts are possible in strong
    thunderstorms late this afternoon and evening.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Gosselin
161 
WGUS63 KLSX 210100
FFALSX

Flood Watch
National Weather Service St Louis MO
800 PM CDT Sun Apr 20 2025

MOZ041-042-047>051-059-072-210200-
/O.CAN.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Boone MO-Audrain MO-Moniteau MO-Cole MO-Osage MO-Callaway MO-
Montgomery MO-Gasconade MO-Crawford MO-
Including the cities of Fulton, Mexico, Jefferson City, and
Columbia
800 PM CDT Sun Apr 20 2025

...FLOOD WATCH IS CANCELLED...

The Flash Flood Watch is cancelled for portions of central and east 
central Missouri, including the following areas, in central 
Missouri, Audrain MO, Boone MO, Callaway MO, Cole MO, Moniteau MO 
and Osage MO. In east central Missouri, Crawford MO, Gasconade MO 
and Montgomery MO.

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

$$

ILZ058>060-064-065-069-070-074-079-098>102-MOZ036-052-060>065-
073>075-084-085-099-210600-
/O.CON.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Calhoun IL-Jersey IL-Madison
IL-Saint Clair IL-Monroe IL-Pike MO-Lincoln MO-Warren MO-Saint
Charles MO-Franklin MO-Saint Louis MO-Saint Louis City MO-
Jefferson MO-Washington MO-Saint Francois MO-Sainte Genevieve MO-
Iron MO-Madison MO-Reynolds MO-
Including the cities of Vandalia, Edwardsville, Belleville,
Salem, Washington, Cahokia, Centralia, Saint Charles, Sullivan,
Bowling Green, Saint Louis, Union, Chester, Farmington, Alton,
Sparta, and Litchfield
800 PM CDT Sun Apr 20 2025

...FLOOD WATCH REMAINS IN EFFECT UNTIL 1 AM CDT MONDAY...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...Portions of Illinois, including the following areas, Bond 
  IL, Calhoun IL, Clinton IL, Fayette IL, Greene IL, Jersey IL, 
  Macoupin IL, Madison IL, Marion IL, Monroe IL, Montgomery IL, 
  Randolph IL, Saint Clair IL and Washington IL and Missouri, 
  including the following areas, Franklin MO, Iron MO, Jefferson MO, 
  Lincoln MO, Madison MO, Pike MO, Reynolds MO, Saint Charles MO, 
  Saint Francois MO, Saint Louis City MO, Saint Louis MO, Sainte 
  Genevieve MO, Warren MO and Washington MO.

* WHEN...Until 1 AM CDT Monday.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Brief heavy downpours remain possible over the next few
    hours.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Gosselin
054 
WGUS63 KLSX 210143
FFALSX

Flood Watch
National Weather Service St Louis MO
843 PM CDT Sun Apr 20 2025

ILZ098-MOZ036-052-060>062-073-084-099-210245-
/O.CAN.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Calhoun IL-Pike MO-Lincoln MO-Warren MO-Saint Charles MO-Franklin
MO-Washington MO-Iron MO-Reynolds MO-
Including the cities of Washington, Saint Charles, Sullivan,
Bowling Green, and Union
843 PM CDT Sun Apr 20 2025

...FLOOD WATCH IS CANCELLED...

The Flash Flood Watch is cancelled for portions of southwest 
Illinois, including the following area, Calhoun IL and Missouri, 
including the following areas, Franklin MO, Iron MO, Lincoln MO, 
Pike MO, Reynolds MO, Saint Charles MO, Warren MO and Washington MO.

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

$$

ILZ058>060-064-065-069-070-074-079-099>102-MOZ063>065-074-075-085-
210600-
/O.CON.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Jersey IL-Madison IL-Saint
Clair IL-Monroe IL-Saint Louis MO-Saint Louis City MO-Jefferson
MO-Saint Francois MO-Sainte Genevieve MO-Madison MO-
Including the cities of Vandalia, Edwardsville, Belleville,
Salem, Cahokia, Centralia, Saint Louis, Chester, Farmington,
Alton, Sparta, and Litchfield
843 PM CDT Sun Apr 20 2025

...FLOOD WATCH REMAINS IN EFFECT UNTIL 1 AM CDT MONDAY...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...Portions of Illinois, including the following areas, Bond 
  IL, Clinton IL, Fayette IL, Greene IL, Jersey IL, Macoupin IL, 
  Madison IL, Marion IL, Monroe IL, Montgomery IL, Randolph IL, 
  Saint Clair IL and Washington IL and Missouri, including the 
  following areas, Jefferson MO, Madison MO, Saint Francois MO, 
  Saint Louis City MO, Saint Louis MO and Sainte Genevieve MO.

* WHEN...Until 1 AM CDT Monday.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - One more round of showers and storms will impact the area
    over the next couple of hours.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Gosselin
708 
WGUS63 KLSX 210251
FFALSX

Flood Watch
National Weather Service St Louis MO
951 PM CDT Sun Apr 20 2025

ILZ058-099-MOZ063>065-074-075-085-210400-
/O.CAN.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greene IL-Jersey IL-Saint Louis MO-Saint Louis City MO-Jefferson
MO-Saint Francois MO-Sainte Genevieve MO-Madison MO-
Including the cities of Saint Louis and Farmington
951 PM CDT Sun Apr 20 2025

...FLOOD WATCH IS CANCELLED...

The Flash Flood Watch is cancelled for portions of southwest 
Illinois, including the following areas, Greene IL and Jersey IL and 
Missouri, including the following areas, Jefferson MO, Madison MO, 
Saint Francois MO, Saint Louis City MO, Saint Louis MO and Sainte 
Genevieve MO.

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

$$

ILZ059-060-064-065-069-070-074-079-100>102-210600-
/O.CON.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-Marion IL-
Washington IL-Randolph IL-Madison IL-Saint Clair IL-Monroe IL-
Including the cities of Belleville, Vandalia, Edwardsville,
Salem, Alton, Cahokia, Chester, Litchfield, Sparta, and Centralia
951 PM CDT Sun Apr 20 2025

...FLOOD WATCH REMAINS IN EFFECT UNTIL 1 AM CDT MONDAY...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...Portions of south central and southwest Illinois, 
  including the following areas, in south central Illinois, Bond IL, 
  Clinton IL, Fayette IL, Marion IL, Montgomery IL and Washington 
  IL. In southwest Illinois, Macoupin IL, Madison IL, Monroe IL, 
  Randolph IL and Saint Clair IL.

* WHEN...Until 1 AM CDT Monday.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

$$

Jaja
609 
WGUS63 KLSX 210322
FFALSX

Flood Watch
National Weather Service St Louis MO
1022 PM CDT Sun Apr 20 2025

ILZ059-079-100>102-210430-
/O.CAN.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Macoupin IL-Randolph IL-Madison IL-Saint Clair IL-Monroe IL-
Including the cities of Belleville, Edwardsville, Cahokia, Alton,
Chester, and Sparta
1022 PM CDT Sun Apr 20 2025

...FLOOD WATCH IS CANCELLED...

The Flash Flood Watch is cancelled for a portion of southwest 
Illinois, including the following areas, Macoupin IL, Madison IL, 
Monroe IL, Randolph IL and Saint Clair IL.

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

$$

ILZ060-064-065-069-070-074-210600-
/O.CON.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Montgomery IL-Bond IL-Fayette IL-Clinton IL-Marion IL-Washington
IL-
Including the cities of Salem, Vandalia, Litchfield, and
Centralia
1022 PM CDT Sun Apr 20 2025

...FLOOD WATCH REMAINS IN EFFECT UNTIL 1 AM CDT MONDAY...

* WHAT...Flash flooding caused by excessive rainfall continues to be 
  possible.

* WHERE...A portion of south central Illinois, including the 
  following areas, Bond IL, Clinton IL, Fayette IL, Marion IL, 
  Montgomery IL and Washington IL.

* WHEN...Until 1 AM CDT Monday.

* IMPACTS...Excessive runoff may result in flooding of rivers, 
  creeks, streams, and other low-lying and flood-prone locations.

$$

Jaja
164 
WGUS63 KLSX 210359
FFALSX

Flood Watch
National Weather Service St Louis MO
1059 PM CDT Sun Apr 20 2025

ILZ060-064-065-069-070-074-210500-
/O.CAN.KLSX.FA.A.0002.000000T0000Z-250421T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Montgomery IL-Bond IL-Fayette IL-Clinton IL-Marion IL-Washington
IL-
Including the cities of Salem, Vandalia, Litchfield, and
Centralia
1059 PM CDT Sun Apr 20 2025

...FLOOD WATCH IS CANCELLED...

The Flash Flood Watch is cancelled for a portion of south central 
Illinois, including the following areas, Bond IL, Clinton IL, 
Fayette IL, Marion IL, Montgomery IL and Washington IL.

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

$$

Jaja

What forecasters said that day

The local office's own words before this flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS St. Louis, MO wrote its last area forecast discussion before this flood watch went out at Apr 17, 12:16 PM CDT, 1 hour 38 minutes earlier. Its key messages:

  • -There is a low threat for severe thunderstorms across the area Friday afternoon and evening, with large hail, and to a lesser extent damaging winds, the main hazards. -The heavy rainfall and flooding threat continues to increase near and along I-44 (MO) and I-70 (IL), with 3-5" of rain possible through Monday morning. -There remains a conditional chance for a strong to severe thunderstorm or two across southeastern missouri and southern Illinois Sunday.
Area forecast discussion, Apr 17, 12:16 PM CDT, 1 hour 38 minutes before
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1216 PM CDT Thu Apr 17 2025

.KEY MESSAGES...

-There is a low threat for severe thunderstorms across the area
Friday afternoon and evening, with large hail, and to a lesser
extent damaging winds, the main hazards.

-The heavy rainfall and flooding threat continues to increase near
and along I-44 (MO) and I-70 (IL), with 3-5" of rain possible
through Monday morning.

-There remains a conditional chance for a strong to severe
thunderstorm or two across southeastern missouri and southern
Illinois Sunday.

&&

.SHORT TERM...  (Through Late Friday Afternoon)
Issued at 327 AM CDT Thu Apr 17 2025

Showers and a few thunderstorms will exit the forecast area this
morning as the upper level jet entrance and low-level jet forcing
this precipitation shift east/northeastward out of the CWA. The
remainder of the day will be warm and dry with low-level southerly
flow helping temperatures warm an additional few degrees from
yesterday, with some portions of central Missouri touching 80 for
their high.

Southwesterly flow will dominate the mid-level pattern by this
evening. Overnight a mid-level disturbance will combine with the
ramp up of the low-level jet in the vicinity of a surface
low/triple point to spawn showers and thunderstorms northwest of
the forecast area over Iowa. Convection is expected to form and
track northeast to east with the deep layer shear, missing our
forecast area all together, so we have pulled the threat of strong
to severe thunderstorms from our messaging. The surface low will
be positioned across the intersection of NE-IA-MO-KS overnight,
but will gradually track to the northeast through Iowa during the
day, helping to advance a cold front into the forecast area by the
afternoon. Southwesterly flow ahead of the approaching cold front
will pull warm, moist air into the region, pushing dewpoints into
the 60s and high temperatures into the 80s areawide. Convection
will form ahead of and along the front during the late afternoon
and evening, driven by surface convergence and mid-level
disturbances.

Instability will form ahead of the front, with the HREF and
deterministic models indicating 1000-2000 J/kg of SBCAPE available
across the forecast area. Strong 0-6 km shear (50+ kts) will also be
available ahead of and along the front to organize any severe
thunderstorms that form. Most guidance also continues to show a
strong low-level warm nose inhibiting surface based convection ahead
of the cold front during the afternoon, although a few sources do
show CIN eroding during the afternoon. If surface based convection
is able to form, large hail and damaging winds would be favored
threats while the tornado risk would remain very low due to veered
(and therefore unfavorable) 0-1 km shear. Elevated convection, which
is more favored at the moment, would result in large hail as the
main threat.

Delia

&&

.LONG TERM...  (Friday Night through Wednesday)
Issued at 327 AM CDT Thu Apr 17 2025

The front will stall out and remain quasi-stationary across
southern Missouri/Illinois over the weekend, focusing numerous
rounds of showers and thunderstorms that will move through the
region. These rounds will be driven by the almost continuous
stream of mid-level disturbances along the southwesterly flow.
Guidance continues to hone in on I-44 (MO) and I-70 (IL) as the
location for the axis of heaviest rainfall as the surface and
elevated fronts waggle north and south slightly with each passing
wave. A few thunderstorms will mix in during Saturday morning as
SREF guidance shows a 50-70% chance of at least 250 J/kg of MUCAPE
along the axis of heavy rainfall. These thunderstorms will
locally enhance rainfall amounts. Currently, a swath of 40-50%
chance for at least 3" of rain through 7 AM Monday exists across
the axis, with a 10-20% chance for exceeding 4.5" of rain. In
areas where thunderstorms linger Friday night into Saturday
morning, rainfall amounts closer to 4.5" are expected.

The bulk of the rainfall (2-3") will fall from early Saturday
morning through Saturday night, and is expected to fall on soil
primed from convection Friday afternoon and evening. Flooding of low
lying areas is possible, particularly where thunderstorms linger.
Additionally, at least minor flooding is expected along the Meramec,
Big, Bourbeuse, and Black rivers and more significant rises along
the creeks and streams in those basins.

Through the weekend the mid-level flow will remain southwesterly as
a trough swings from the Four Corners region into the mid-
Mississippi Valley. At the surface a low will move northeast from
Texas into the forecast area late Sunday into early Monday, bringing
one more shot of rainfall to the entire forecast area. Despite the
strong forcing, instability will be the limiting factor for strong
to severe thunderstorm development with only a 50% chance for MUCAPE
greater than 500 J/kg, 0-6 km shear greater than 30 kts, and CIN
less than -25 J/kg. I cannot rule out a strong to severe
thunderstorm, but confidence in this developing remains low, and we
are not publicly messaging this potential. The system will exit
the area Monday, and an advancing surface high will help to clear
out any remaining light precipitation. The surface high will also
help keep the region dry through a portion of Tuesday before
chances for precipitation return to the forecast, driven by
multiple disturbances passing through the quasi-zonal mid-level
flow.

Delia

&&

.AVIATION...  (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1213 PM CDT Thu Apr 17 2025

Rain has moved out of the area, leaving mostly clear skies and
gusty southerly winds in its wake. Winds will remain elevated
through the afternoon before tailing off slightly overnight. Winds
just of the deck will remain rather strong through the night, but
with elevated surface winds, I don't think we'll quite meet LLWS
criteria. Winds will again be gusty tomorrow before a cold front
moves into the area in the afternoon. Showers and storms are
expected along and behind this front, though precipitation isn't
expected to reach the terminals until after the TAF period.

BSH

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&

WFO LSX
Hazardous weather outlook, Apr 17, 3:38 AM CDT, 10 hours 16 minutes before
Hazardous Weather Outlook
National Weather Service St Louis MO
338 AM CDT Thu Apr 17 2025

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-180845-
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Adams IL-Brown IL-Pike IL-
Calhoun IL-Jersey IL-Madison IL-Saint Clair IL-Monroe IL-Knox MO-
Lewis MO-Shelby MO-Marion MO-Monroe MO-Ralls MO-Pike MO-Boone MO-
Audrain MO-Moniteau MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-
Lincoln MO-Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-
Saint Louis MO-Saint Louis City MO-Jefferson MO-Crawford MO-
Washington MO-Saint Francois MO-Sainte Genevieve MO-Iron MO-
Madison MO-Reynolds MO-
338 AM CDT Thu Apr 17 2025

This Hazardous Weather Outlook is for portions of eastern and
central Missouri as well as west central and southwest Illinois.

.DAY ONE...Today and tonight.

A few thunderstorms are possible across the area this morning.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Multiple rounds of thunderstorms are expected to impact parts of the
area Friday through Sunday. A few strong to severe thunderstorms are
also possible late Friday afternoon and evening areawide.

Locally heavy rainfall appears increasingly likely Friday night
through early Sunday which could lead to both river flooding and
localized flash flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Delia

Nearby

Flood Watches in Missouri, 2025Flood Watches in Illinois, 2025Every flood watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.