River Flood Warning 94, NWS St. Louis, MO

033 
WGUS83 KLSX 161518
FLSLSX

Flood Statement
National Weather Service St Louis MO
1018 AM CDT Tue Jun 16 2026

...The Flood Warning continues for the following rivers in
Missouri...

  Meramec River near Arnold.

River forecasts are based on observed precipitation and forecast
precipitation for the next 24 hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Motorists should not attempt to drive around barricades or drive cars
through flooded areas.

This product, along with additional weather and stream information,
is available at https://water.noaa.gov/wfo/lsx

&&

MOC099-189-180330-
/O.EXT.KLSX.FL.W.0094.000000T0000Z-260620T1000Z/
/ARNM7.1.ER.260617T0400Z.260618T0000Z.260619T0400Z.NO/
1018 AM CDT Tue Jun 16 2026

...FLOOD WARNING NOW IN EFFECT UNTIL LATE FRIDAY NIGHT...

* WHAT...Minor flooding is forecast.

* WHERE...Meramec River near Arnold.

* WHEN...Until late Friday night.

* IMPACTS...At 24.7 feet, Hawkins Road south of Meramec Bottom Road
  begins flooding.

* ADDITIONAL DETAILS...
  - At 10:00 AM CDT Tuesday the stage was 23.5 feet.
  - Forecast...The river is expected to rise above flood stage late
    this evening to a crest of 24.7 feet tomorrow evening. It will
    then fall below flood stage late Thursday evening.
  - Flood stage is 24.0 feet.



&&


All Times CDT Fld   Observed  Forecasts (7:00 am)
Location      Stg     Stage   Wed   Thu   Fri   Sat   Sun

Meramec River
 Arnold       24.0    23.5    24.4  24.6  23.4  19.7  16.1



&&

LAT...LON 3847 9044 3847 9032 3840 9033 3837 9036
      3841 9036 3842 9037 3843 9036 3845 9036
      3845 9041


$$

Maples

928 
WGUS83 KLSX 170310
FLSLSX

Flood Statement
National Weather Service St Louis MO
1010 PM CDT Tue Jun 16 2026

...The Flood Warning continues for the following rivers in
Missouri...Illinois...

  Missouri River at St. Charles.

  Mississippi River at Chester.

  Mississippi River at Clarksville.

  Mississippi River at Mel Price LD.

  Meramec River near Arnold.

  Illinois River at Hardin.

  Mississippi River at Louisiana.

...The Flood Warning is extended for the following rivers in
Missouri...Illinois...

  Missouri River at Hermann.

  Missouri River near Chamois.

  Illinois River at Valley City.

River forecasts are based on observed precipitation and forecast
precipitation for the next 24 hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Motorists should not attempt to drive around barricades or drive cars
through flooded areas.

This product, along with additional weather and stream information,
is available at https://water.noaa.gov/wfo/lsx

&&

MOC183-189-181515-
/O.EXT.KLSX.FL.W.0096.000000T0000Z-260618T1800Z/
/SCLM7.1.ER.260616T1747Z.260617T0300Z.260617T1200Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING NOW IN EFFECT UNTIL THURSDAY AFTERNOON...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

* WHERE...Missouri River at St. Charles.

* WHEN...Until Thursday afternoon.

* IMPACTS...At 25.0 feet, Downstream near this stage, Missouri Route
  H at Island Road and agricultural bottomland may begin flooding,
  depending on Mississippi River flow and backwater.

* ADDITIONAL DETAILS...
  - At 10:00 PM CDT Tuesday the stage was 25.2 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 10:00 PM CDT Tuesday was 25.2 feet.
  - Forecast...The river is expected to fall below flood stage
    tomorrow morning and continue falling to 17.9 feet Sunday
    evening.
  - Flood stage is 25.0 feet.



&&


All Times CDT Fld   Observed  Forecasts (7:00 am)
Location      Stg     Stage   Thu   Fri   Sat   Sun   Mon

Missouri River
 St. Charles  25.0    25.2    24.0  21.8  19.6  18.2  MSG



&&

LAT...LON 3892 9036 3884 9013 3878 9016 3883 9031
      3869 9045 3860 9069 3867 9076


$$

ILC077-157-MOC157-186-181515-
/O.EXT.KLSX.FL.W.0088.000000T0000Z-260621T1108Z/
/CHSI2.1.ER.260615T1516Z.260618T1800Z.260620T0508Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING NOW IN EFFECT UNTIL SUNDAY MORNING...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

* WHERE...Mississippi River at Chester.

* WHEN...Until Sunday morning.

* IMPACTS...At 28.0 feet, Unleveed islands near Chester and the
  prison farm floods.

* ADDITIONAL DETAILS...
  - At 10:00 PM CDT Tuesday the stage was 28.0 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 10:00 PM CDT Tuesday was 28.1 feet.
  - Forecast...The river is expected to rise to a crest of 28.8 feet
    early Thursday afternoon. It will then fall below flood stage
    early Saturday morning.
  - Flood stage is 27.0 feet.



&&


All Times CDT    Fld   Observed  Forecasts (7:00 am)
Location         Stg     Stage   Thu   Fri   Sat   Sun   Mon

Mississippi River
 Chester         27.0    28.0    28.7  28.6  26.3  23.5  21.8



&&

LAT...LON 3799 8992 3790 8977 3786 8973 3776 8945
      3769 8941 3769 8959 3786 8995 3795 9005


$$

MOC073-139-181515-
/O.EXT.KLSX.FL.W.0086.000000T0000Z-260619T0900Z/
/HRNM7.1.ER.260615T0630Z.260617T0000Z.260618T0300Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING NOW IN EFFECT UNTIL LATE THURSDAY NIGHT...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

* WHERE...Missouri River at Hermann.

* WHEN...Until late Thursday night.

* IMPACTS...At 22.3 feet, Southern portions of Old Rock Road and
  Twisters Road south of Rhineland begin flooding near this height.

* ADDITIONAL DETAILS...
  - At 9:30 PM CDT Tuesday the stage was 22.3 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 9:30 PM CDT Tuesday was 22.4 feet.
  - Forecast...The river is expected to fall below flood stage late
    tomorrow evening and continue falling to 12.4 feet Tuesday, June
    23.
  - Flood stage is 21.0 feet.



&&


All Times CDT Fld   Observed  Forecasts (7:00 am)
Location      Stg     Stage   Thu   Fri   Sat   Sun   Mon

Missouri River
 Hermann      21.0    22.3    20.0  16.6  14.4  13.4  12.9



&&

LAT...LON 3873 9160 3875 9136 3866 9119 3859 9119
      3867 9144 3865 9160


$$

ILC013-MOC163-181515-
/O.EXT.KLSX.FL.W.0084.000000T0000Z-260619T0000Z/
/CLKM7.1.ER.260613T0630Z.260615T1030Z.260617T1800Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING NOW IN EFFECT UNTIL THURSDAY EVENING...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

* WHERE...Mississippi River at Clarksville.

* WHEN...Until Thursday evening.

* IMPACTS...At 25.5 feet, State Route P east of Elsberry begins
  flooding just east of the levee.

* ADDITIONAL DETAILS...
  - At 10:00 PM CDT Tuesday the stage was 25.5 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 10:00 PM CDT Tuesday was 25.8 feet.
  - Forecast...The river is expected to fall below flood stage early
    tomorrow afternoon and continue falling to 21.2 feet Tuesday,
    June 23.
  - Flood stage is 25.0 feet.



&&


All Times CDT    Fld   Observed  Forecasts (7:00 am)
Location         Stg     Stage   Thu   Fri   Sat   Sun   Mon

Mississippi River
 Clarksville     25.0    25.5    24.2  23.1  22.4  22.2  21.9



&&

LAT...LON 3939 9097 3946 9088 3940 9081 3932 9075
      3925 9071 3925 9083 3930 9090 3932 9088
      3936 9092 3935 9095


$$

MOC027-151-181515-
/O.EXT.KLSX.FL.W.0082.000000T0000Z-260619T0224Z/
/CMSM7.1.ER.000000T0000Z.260616T1445Z.260617T1424Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING NOW IN EFFECT UNTIL THURSDAY EVENING...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

* WHERE...Missouri River near Chamois.

* WHEN...Until Thursday evening.

* IMPACTS...At 17.0 feet, Flood Stage:  Lower lying bottom land
  begins to flood.

* ADDITIONAL DETAILS...
  - At 9:45 AM CDT Tuesday the stage was 18.3 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 9:45 AM CDT Tuesday was 18.3 feet.
  - Forecast...The river is expected to fall below flood stage late
    tomorrow morning and continue falling to 8.3 feet Sunday evening.
  - Flood stage is 17.0 feet.



&&


All Times CDT Fld   Observed  Forecasts (7:00 am)
Location      Stg     Stage   Thu   Fri   Sat   Sun   Mon

Missouri River
 Chamois      17.0    18.3    14.0  11.5  9.5   8.6   MSG



&&

LAT...LON 3864 9198 3871 9185 3873 9160 3865 9160
      3864 9181 3858 9194


$$

ILC149-171-181515-
/O.EXT.KLSX.FL.W.0093.260620T0000Z-000000T0000Z/
/VALI2.1.ER.260620T0000Z.260623T0000Z.000000T0000Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING NOW IN EFFECT FROM FRIDAY EVENING UNTIL FURTHER
NOTICE...

* WHAT...Minor flooding is forecast.

* WHERE...Illinois River at Valley City.

* WHEN...From Friday evening until further notice.

* IMPACTS...At 14.0 feet, The road to Norbut Fish and Wildlife area
  is flooded.

* ADDITIONAL DETAILS...
  - At 10:00 PM CDT Tuesday the stage was 13.3 feet.
  - Forecast...The river is expected to rise above flood stage Friday
    evening and continue rising to 14.3 feet Monday evening.
    Additional rises are possible thereafter.
  - Flood stage is 14.0 feet.



&&


All Times CDT Fld   Observed  Forecasts (7:00 am)
Location      Stg     Stage   Thu   Fri   Sat   Sun   Mon

Illinois River
 Valley City  14.0    13.3    13.6  13.9  14.0  14.1  14.2



&&

LAT...LON 3977 9067 3977 9053 3969 9056 3962 9052
      3952 9051 3952 9059 3964 9062 3965 9066
      3967 9065


$$

ILC119-MOC183-181515-
/O.CON.KLSX.FL.W.0095.000000T0000Z-260619T1800Z/
/ALNI2.1.ER.260617T0341Z.260617T1200Z.260618T1200Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING REMAINS IN EFFECT UNTIL FRIDAY AFTERNOON...

* WHAT...Minor flooding is forecast.

* WHERE...Mississippi River at Mel Price LD.

* WHEN...Until Friday afternoon.

* IMPACTS...At 20.8 feet, Unprotected farm land begins to flood

* ADDITIONAL DETAILS...
  - At 10:00 PM CDT Tuesday the stage was 21.0 feet.
  - Forecast...The river is expected to rise above flood stage late
    this evening to a crest of 21.2 feet tomorrow morning. It will
    then fall below flood stage Thursday morning.
  - Flood stage is 21.0 feet.



&&


All Times CDT    Fld   Observed  Forecasts (7:00 am)
Location         Stg     Stage   Thu   Fri   Sat   Sun   Mon

Mississippi River
 Mel Price LD    21.0    21.0    21.0  19.6  17.7  16.4  15.7



&&

LAT...LON 3889 9014 3889 9009 3881 9001 3881 9017
      3884 9018


$$

MOC099-189-181515-
/O.CON.KLSX.FL.W.0094.000000T0000Z-260620T1000Z/
/ARNM7.1.ER.260617T0900Z.260618T0000Z.260619T0400Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING REMAINS IN EFFECT UNTIL LATE FRIDAY NIGHT...

* WHAT...Minor flooding is forecast.

* WHERE...Meramec River near Arnold.

* WHEN...Until late Friday night.

* IMPACTS...At 24.7 feet, Hawkins Road south of Meramec Bottom Road
  begins flooding.

* ADDITIONAL DETAILS...
  - At 9:30 PM CDT Tuesday the stage was 23.8 feet.
  - Forecast...The river is expected to rise above flood stage late
    tonight to a crest of 24.4 feet tomorrow evening. It will then
    fall below flood stage late Thursday evening.
  - Flood stage is 24.0 feet.



&&


All Times CDT Fld   Observed  Forecasts (7:00 am)
Location      Stg     Stage   Thu   Fri   Sat   Sun   Mon

Meramec River
 Arnold       24.0    23.8    24.4  23.5  20.6  17.0  14.9



&&

LAT...LON 3847 9044 3847 9032 3840 9033 3837 9036
      3841 9036 3842 9037 3843 9036 3845 9036
      3845 9041


$$

ILC013-061-083-181515-
/O.CON.KLSX.FL.W.0092.000000T0000Z-000000T0000Z/
/HARI2.1.ER.260616T1030Z.260622T0600Z.000000T0000Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING REMAINS IN EFFECT UNTIL FURTHER NOTICE...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

* WHERE...Illinois River at Hardin.

* WHEN...Until further notice.

* IMPACTS...At 25.0 feet, Flood Stage.  Lowland flooding of
  unprotected agricultural land begins.

* ADDITIONAL DETAILS...
  - At 10:00 PM CDT Tuesday the stage was 25.2 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 10:00 PM CDT Tuesday was 25.2 feet.
  - Forecast...The river is expected to remain steady above flood
    stage at 25.2 feet.
  - Flood stage is 25.0 feet.



&&


All Times CDT Fld   Observed  Forecasts (7:00 am)
Location      Stg     Stage   Thu   Fri   Sat   Sun   Mon

Illinois River
 Hardin       25.0    25.2    25.4  25.5  25.5  25.5  25.6



&&

LAT...LON 3952 9064 3952 9052 3942 9054 3935 9051
      3931 9053 3898 9052 3897 9049 3890 9054
      3898 9062 3923 9065


$$

ILC149-MOC163-181515-
/O.CON.KLSX.FL.W.0083.000000T0000Z-260619T0900Z/
/LUSM7.1.ER.260612T1715Z.260615T1000Z.260618T0300Z.NO/
1010 PM CDT Tue Jun 16 2026

...FLOOD WARNING REMAINS IN EFFECT UNTIL LATE THURSDAY NIGHT...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

* WHERE...Mississippi River at Louisiana.

* WHEN...Until late Thursday night.

* IMPACTS...At 15.0 feet, The first quarter mile of Edison Avenue
  beyond the railroad tracks begins flooding near this height.

* ADDITIONAL DETAILS...
  - At 10:00 PM CDT Tuesday the stage was 15.7 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 10:00 PM CDT Tuesday was 16.1 feet.
  - Forecast...The river is expected to fall below flood stage late
    tomorrow evening and continue falling to 12.2 feet Tuesday, June
    23.
  - Flood stage is 15.0 feet.



&&


All Times CDT    Fld   Observed  Forecasts (7:00 am)
Location         Stg     Stage   Thu   Fri   Sat   Sun   Mon

Mississippi River
 Louisiana       15.0    15.7    14.6  13.6  13.0  12.8  12.6



&&

LAT...LON 3946 9110 3953 9099 3946 9088 3939 9097
      3941 9100 3939 9103


$$

Elmore

452 
WGUS83 KLSX 171738
FLSLSX

Flood Statement
National Weather Service St Louis MO
1238 PM CDT Wed Jun 17 2026

...The Flood Warning continues for the following rivers in
Missouri...

  Meramec River near Arnold.

River forecasts are based on observed precipitation and forecast
precipitation for the next 24 hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive cars
through flooded areas.

This product, along with additional weather and stream information,
is available at https://water.noaa.gov/wfo/lsx

&&

MOC099-189-190545-
/O.EXT.KLSX.FL.W.0094.000000T0000Z-260620T0600Z/
/ARNM7.1.ER.260617T1140Z.260618T0600Z.260619T0000Z.NO/
1238 PM CDT Wed Jun 17 2026

...FLOOD WARNING NOW IN EFFECT UNTIL LATE FRIDAY NIGHT...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

* WHERE...Meramec River near Arnold.

* WHEN...Until late Friday night.

* IMPACTS...At 24.0 feet, Corisande Hills Road begins flooding at
  this height.  Meramec Bottom Road between Hagemann Road and Highway
  21 begins flooding.

* ADDITIONAL DETAILS...
  - At 12:00 PM CDT Wednesday the stage was 24.0 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 12:00 PM CDT Wednesday was 24.1 feet.
  - Forecast...The river is expected to rise to a crest of 24.3 feet
    just after midnight tonight. It will then fall below flood stage
    tomorrow evening.
  - Flood stage is 24.0 feet.



&&


All Times CDT Fld   Observed  Forecasts (7:00 am)
Location      Stg     Stage   Thu   Fri   Sat   Sun   Mon

Meramec River
 Arnold       24.0    24.0    24.3  23.4  21.0  18.6  17.4



&&

LAT...LON 3847 9044 3847 9032 3840 9033 3837 9036
      3841 9036 3842 9037 3843 9036 3845 9036
      3845 9041


$$

Fuchs

177 
WGUS83 KLSX 180202
FLSLSX

Flood Statement
National Weather Service St Louis MO
902 PM CDT Wed Jun 17 2026

...The Flood Warning is extended for the following rivers in
Missouri...

  Meramec River near Arnold.

River forecasts are based on observed precipitation and forecast
precipitation for the next 24 hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive cars
through flooded areas.

This product, along with additional weather and stream information,
is available at https://water.noaa.gov/wfo/lsx

&&

MOC099-189-191415-
/O.EXT.KLSX.FL.W.0094.000000T0000Z-260620T1200Z/
/ARNM7.1.ER.260617T1140Z.260618T1200Z.260619T0600Z.NO/
902 PM CDT Wed Jun 17 2026

...FLOOD WARNING NOW IN EFFECT UNTIL SATURDAY MORNING...

* WHAT...Minor flooding is occurring and minor flooding is forecast.

* WHERE...Meramec River near Arnold.

* WHEN...Until Saturday morning.

* IMPACTS...At 24.0 feet, Corisande Hills Road begins flooding at
  this height.  Meramec Bottom Road between Hagemann Road and Highway
  21 begins flooding.

* ADDITIONAL DETAILS...
  - At 8:30 PM CDT Wednesday the stage was 24.1 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 8:30 PM CDT Wednesday was 24.2 feet.
  - Forecast...The river is expected to rise to a crest of 24.3 feet
    tomorrow morning. It will then fall below flood stage early
    Friday morning.
  - Flood stage is 24.0 feet.



&&


All Times CDT Fld   Observed  Forecasts (7 am)
Location      Stg     Stage   Fri   Sat   Sun   Mon   Tue

Meramec River
 Arnold       24.0    24.1    23.6  21.2  18.7  17.4  16.7



&&

LAT...LON 3847 9044 3847 9032 3840 9033 3837 9036
      3841 9036 3842 9037 3843 9036 3845 9036
      3845 9041


$$

Jaja

768 
WGUS83 KLSX 181653
FLSLSX

Flood Statement
National Weather Service St Louis MO
1153 AM CDT Thu Jun 18 2026

...The Flood Warning is cancelled for the following rivers in
Missouri...

  Meramec River near Arnold.

River forecasts are based on observed precipitation and forecast
precipitation for the next 24 hours.

MOC099-189-181800-
/O.CAN.KLSX.FL.W.0094.000000T0000Z-260618T1653Z/
/ARNM7.1.ER.260617T1140Z.260618T0200Z.260618T1537Z.NO/
1153 AM CDT Thu Jun 18 2026

...FLOOD WARNING IS CANCELLED...

The Flood Warning is cancelled for
  the Meramec River near Arnold.

* ADDITIONAL DETAILS...
  - At 11:30 AM CDT Thursday the stage was 24.0 feet.
  - Recent Activity...The river rose above flood stage on June 17,
    cresting near 24.2 feet overnight. It fell below flood stage late
    this morning, June 18.
  - Forecast...The river is expected to continue falling over the
    coming days to as low as 17.4 feet by Wednesday morning.



&&


All Times CDT Fld   Observed  Forecasts (7 am)
Location      Stg     Stage   Fri   Sat   Sun   Mon   Tue

Meramec River
 Arnold       24.0    24.0    23.3  21.8  19.9  19.0  18.3



&&

LAT...LON 3847 9044 3847 9032 3840 9033 3837 9036
      3841 9036 3842 9037 3843 9036 3845 9036
      3845 9041


$$

Kimble

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
621 PM CDT Mon Jun 15 2026

.KEY MESSAGES...

- Strong to marginally-severe thunderstorms exists tomorrow along
  and south of I-70 in Missouri and Illinois, with isolated
  instances of damaging wind being the main threat.

- A more noteworthy chance for severe weather exists across much
  of the region Wednesday afternoon. The strongest thunderstorms
  would threaten damaging wind and brief tornadoes, along with
  locally-heavy rain.

&&

.SHORT TERM...  (Through Late Tuesday Night)
Issued at 336 PM CDT Mon Jun 15 2026

After another pleasant day today, a weak cold front is on tap to
bring a round of scattered showers and possibly a few thunderstorms
during the day tomorrow. This doesn't pose nearly as great a threat
as Wednesday's front, and the latter will be discussed in more
detail in the long term portion of the discussion. Before we get to
all of that, downright fantastic weather is in place throughout the
mid-Mississippi River valley, thanks to mild northwest flow and
seasonably low dewpoints in the upper 40s to low 50s. While
afternoon heating has been enough to generate a deck of scattered
fairweather cumulus across the southern half of Missouri and much of
Illinois, dry conditions are expected to persist the rest of the
day. Overnight, northwest winds will back to the southwest and
become nearly calm, and nearly clear skies will allow for efficient
radiative cooling conditions. We may also see some shallow, patchy
fog in Ozark river valley bottoms, but relatively low humidity will
prevent this in most other areas.

During the day tomorrow, a shortwave will round the base of the
synoptic trough across the Great Lakes and eastern Canada,
driving a weak cold front into the area between early morning and
early afternoon. Ahead of it, increasing southwesterlies will
produce modest moisture advection, and the linear forcing along
the front is expected to squeeze out some scattered showers,
possibly a few thunderstorms. Due to the limited moisture content
(1-1.25 inch PWAT) and scattered coverage, rain amounts are
expected to be limited and many areas are also expected to miss
out entirely. The potential for strong or severe storms is also
limited, but there is just enough instability (500-1000 k/kg) and
wind shear (30-40kt) to support organized updrafts during the
afternoon, particularly from I- 70 southward. Isolated damaging
wind gusts and quarter-sized hail would be the primary threats if
we do see a few stronger cells. While some showers may move into
the area in the morning, stronger cells should be limited to the
afternoon (roughly 1-8pm) and weaken near and after sunset.

BRC

&&

.LONG TERM...  (Wednesday through Next Monday)
Issued at 336 PM CDT Mon Jun 15 2026

By Wednesday morning, a much stronger shortwave/deeper surface low
and jet streak will move through the Midwest and Great Lakes just to
our north. This will initially drive much more robust northward
moisture return into our area during the day Wednesday, followed by
a stronger cold front Wednesday evening and overnight. Before the
cold front arrives, the warm sector airmass is expected to quickly
destabilize thanks to abundant sunshine, increasingly rich low level
moisture (upper 60s / low 70s dewpoints), and steepening mid-level
lapse rates. While subsidence aloft may cut into CAPE projections
just a bit, values between 1000-2000 J/kg of SBCAPE appear rather
likely by mid/late afternoon. Meanwhile, seasonably strong westerly
mid-level flow is also projected to produce ample deep layer shear,
with between 50-60kt currently forecast along and ahead of the
front. Given the above, the bulk parameter space is more than
supportive of strong/severe thunderstorms as the front overturns
this airmass.

The finer scale details are more difficult to determine, and this is
mainly linked to uncertainty in the progression/orientation of the
front and the strength of a capping inversion. Early indications
suggest that as the front moves south and becomes oriented more east
to west, linear storm modes will be favored overall, but exactly how
long this takes to materialize is uncertain at this time range. We
do note some clockwise turning in hodographs initially, so storms
may start off as supercells before being overtaken by the front,
especially if a capping inversion can keep initial updrafts more
isolated. Mid-level lapse rates will also support the potential for
large hail, but this threat will gradually wane if/when storms
become primarily linear. Tornadoes appear possible given the bulk
shear parameters and sufficiently low LCLs, although this threat
will also be tied to how quickly storms transition from supercells
to a linear complex, and is a lower overall threat. Overall,
damaging winds appear most likely of these hazards, with steep low
level lapse rates and relatively high confidence that storms will
eventually become linear. Locally heavy rainfall will also be
possible, due to increasingly rich moisture (PWAT of 1.7-1.9 inches)
and storm motions that become more parallel to the advancing cold
front with time. Storm hazards appear to be maximized across
northeast Missouri and west-central Illinois, with lower
confidence further and further south and later into the night.

Thursday morning the advancing front is expected to slow and
potentially stall across the Ozarks, maintaining additional chances
for showers and thunderstorms through the day. Confidence is very
low regarding this potential at this time, as this will be linked to
how overnight storms and their resulting cold pool impact the
environment. Dry conditions are expected to end the work week
Friday.

Beyond Friday, model guidance has increased probabilities for
more showers and thunderstorms late in the weekend, with a rather
strong ensemble signal for widespread precipitation at some point
between late Saturday and early Monday. Confidence in the
specifics remains low, but there is a robust signal for
anomalously high moisture content (PWAT ensemble means near the
95th percentile) and a relatively high number of ensemble members
forecast heavy rain in our area at that time range. Timing and
location details will need to be ironed out, as there are
considerable QPF differences between the various ensemble clusters
at that time range linked to differences in timing/strength of a
passing shortwave.

BRC

&&

.AVIATION...  (For the 00z TAFs through 00z Tuesday Evening)
Issued at 552 PM CDT Mon Jun 15 2026

Dry and VFR conditions will prevail through tonight ahead of a
cold front that passes through the Mid-Mississippi Valley
tomorrow. Very little moisture will be available to this weak
front as it crosses from northwest to southeast, leading to
scattered coverage of any showers or shallow thunderstorms. The
threat should not last very long at any one location, abating by
sundown at the TAF site. The main threat for the strongest storms
would be wind gusts to 40kts, but nearly all of the convection
would remain much weaker than this.

Outside of the thunderstorms, gusty winds to 20kts can be expected
ahead of and directly behind the front. With the loss of daytime
heating and passing of the front itself, expect the winds to
weaken near sunset as well.

MRB

&&

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

WFO LSX