River Flood Warning 33, NWS St. Louis, MO

406 
WGUS83 KLSX 190033
FLSLSX

Flood Statement
National Weather Service St Louis MO
733 PM CDT Sat Apr 18 2026

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

  Black River near Annapolis.

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.

Rainfall heavier than forecast could cause river levels to rise even
higher than predicted. The National Weather Service will monitor this
developing situation and issue follow up statements as conditions
change.

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

&&

MOC179-201245-
/O.EXT.KLSX.FL.W.0033.000000T0000Z-260420T2248Z/
/ANNM7.1.ER.260418T1900Z.260419T0600Z.260419T1648Z.NO/
733 PM CDT Sat Apr 18 2026

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

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

* WHERE...Black River near Annapolis.

* WHEN...Until Monday afternoon.

* IMPACTS...At 9.0 feet, County Road 372 will begin flooding near
  this height.

* ADDITIONAL DETAILS...
  - At 7:15 PM CDT Saturday the stage was 9.6 feet.
  - Recent Activity...The maximum river stage in the 24 hours ending
    at 7:15 PM CDT Saturday was 9.6 feet.
  - Forecast...The river is expected to rise to a crest of 9.7 feet
    just after midnight tonight. It will then fall below flood stage
    late tomorrow morning.
  - Flood stage is 8.0 feet.



&&


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

Black River
 Annapolis    8.0     9.6     6.1   5.1   4.9   4.8   MSG



&&

LAT...LON 3743 9086 3746 9080 3738 9079 3735 9075
      3721 9076 3721 9080 3732 9080 3737 9085


$$

Delia

615 
WGUS83 KLSX 191410
FLSLSX

Flood Statement
National Weather Service St Louis MO
910 AM CDT Sun Apr 19 2026

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

  Black River near Annapolis.

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

MOC179-191515-
/O.CAN.KLSX.FL.W.0033.000000T0000Z-260419T1410Z/
/ANNM7.1.ER.260418T1900Z.260419T0215Z.260419T1200Z.NO/
910 AM CDT Sun Apr 19 2026

...FLOOD WARNING IS CANCELLED...

The Flood Warning is cancelled for
  the Black River near Annapolis.

* ADDITIONAL DETAILS...
  - At 8:15 AM CDT Sunday the stage was 7.8 feet.
  - Forecast...The river is expected to fall to 4.8 feet Friday
    morning.



&&


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

Black River
 Annapolis    8.0     7.8     5.9   5.2   4.9   4.8   4.8



&&

LAT...LON 3743 9086 3746 9080 3738 9079 3735 9075
      3721 9076 3721 9080 3732 9080 3737 9085


$$

Jaja

Area Forecast Discussion
National Weather Service Saint Louis MO
253 PM CDT Sat Apr 18 2026

.KEY MESSAGES...

- Some locations will reach the mid 30s tonight with less than a
  50% chance for patchy frost Sunday morning. Vegetation that is
  elevated off the ground will be more susceptible to frost.

- A notable warmup begins on Tuesday lasting until at least
  Thursday, when temperatures are expected to be 10 degrees above
  average.

- A period of dry weather is forecast until at least Tuesday night
  when there is a low (20%) for light rain. A better chance for
  showers and thunderstorms returns Thursday night into Friday.

&&

.SHORT TERM...  (Through Late Sunday Night)
Issued at 251 PM CDT Sat Apr 18 2026

Reinforcing low/mid-level CAA behind last night's FROPA has resulted
in temperatures about 15 degrees below average with afternoon highs
generally in the 50s across the entire area. Additionally, cloud
cover has been slower to clear S of I-44 in MO and I-70 in IL, which
has also limited daytime heating across that part of the area.
Surface analysis reveals a surface high pushing eastward near the
Oklahoma Panhandle with high-res guidance settling this high just to
the south overnight. This will lead to light westerly winds and a
clear night allowing for efficient radiational cooling, especially
for low-lying areas that are more sheltered from winds. Given the
setup described above, the coldest temperatures tonight are forecast
to be in the mid 30s for locations across northeast MO/west-central
IL along with low-lying/river valley locations. In these areas,
patchy frost is possible, but should be limited to mostly elevated
and exposed vegetation. The reason for this being warm ground
temperatures (2" soil temps in the 60s/70s) and saturated soils
(resulting in slower temperature change of the soil) helping to keep
the near surface air slightly warmer. Furthermore, with the surface
high across southern MO, light westerly winds are forecast to be
strongest (3-7mph) overnight across northern MO/west-central IL,
which will work to limit frost formation as well.

After a chilly start in the morning, a quick warmup will ensue on
Sunday thanks to weak low-level westerly WAA and abundant solar
insolation under a mostly sunny mid-April sky. As a result,
afternoon temperatures are forecast to reach the 60s areawide,
leading to highs about 10 degrees warmer than today. By Sunday
evening, a surface high slides southward out of Canada into the
Midwest, placing the area within light northeasterly flow. That,
coupled with a mostly clear sky overnight will once again lead to a
rather chilly night with lows forecast in the mid/upper 30s north of
I-70 and lower 40s south.

Peine

&&

.LONG TERM...  (Monday through Next Saturday)
Issued at 251 PM CDT Sat Apr 18 2026

At the start of the extended, the mid-level large-scale pattern
consists of troughing off the West Coast, broad ridging across the
Intermountain West, and troughing over the eastern U.S., placing our
area under northwesterly flow aloft. Long-range deterministic
guidance unveils a weak mid-level shortwave, within the
northwesterly flow, moving across the area Tuesday night. Ahead of
this wave, southerly flow advecting Gulf moisture into the region
will be limited to only the low-levels. As a result, moisture return
remains weak ahead of the arrival of better low/mid-level forcing,
owing to very low chances for light rain. Currently, the LREF
indicates around only a 20% for measurable precipitation Tuesday
night into Wednesday. As the mid-level ridge axis closes in on the
area Wednesday, height rises aloft should allow for continued warm
and dry conditions. By Thursday, long-range guidance is in good
consensus that a longwave trough will be positioned near the
Intermountain West and slowly approaching our area. The result for
us will be the return of deep southwesterly flow that will lead to
abundant warm/moist advection and the return of shower and
thunderstorm chances as early as Thursday night.

As for temperatures, the week will start off rather chilly Monday
morning with southerly low-level flow commencing mid/late day on
Monday, resulting in temperatures rebounding nicely. By the
afternoon, most of the area should be near the mid/upper 60s with
the warmest (low 70s) across the Ozarks. Low-level southerly flow is
forecast to continue Tuesday through Friday, resulting in highs
reaching the 70s/80s each afternoon/evening. Confidence is high in
the continuance of slightly above average temperatures Tuesday into
Thursday as LREF temperatures IQR spreads are only around 3 degrees
and centered on temperatures 5-10 degrees above average. IQR spreads
increase substantially on Friday to 10+ degrees indicating a
potential front nearby. Slightly below normal temperatures may
return next Saturday as temperature IQRs become centered on
temperatures 10 degrees below average.

Peine

&&

.AVIATION...  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1234 PM CDT Sat Apr 18 2026

VFR and dry conditions are forecast at all terminals for the
entire TAF package. Northwesterly surface winds gusting around
25kts today will quickly fade around sunset this evening as a
surface high slides eastward across southern MO. All terminals,
except for KUIN are expected to be calm and variable overnight
until westerly winds pick up tomorrow shortly after sunrise.

Peine

&&

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

WFO LSX

Hazardous Weather Outlook
National Weather Service St Louis MO
258 PM CDT Sat Apr 18 2026

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-192000-
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-
258 PM CDT Sat Apr 18 2026

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

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

There is a chance of thunderstorms late Thursday through Friday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Peine

Preliminary Local Storm Report
National Weather Service St Louis MO
219 PM CDT Sat Apr 18 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0840 PM     Tstm Wnd Dmg     1 N Fulton              38.87N 91.95W
04/17/2026                   Callaway           MO   Trained Spotter

            2 utility poles were downed in Fulton. Very
            large trees downed as well, especially near
            Backers Potato Chips.

&&

LSJ

Preliminary Local Storm Report
National Weather Service St Louis MO
224 PM CDT Sat Apr 18 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0840 PM     Tstm Wnd Dmg     1 NNW Fulton            38.87N 91.95W
04/17/2026                   Callaway           MO   Trained Spotter

            Old KFAL radio tower knocked down.

&&

LSJ

Preliminary Local Storm Report
National Weather Service St Louis MO
227 PM CDT Sat Apr 18 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0840 PM     Tstm Wnd Dmg     1 NNE Fulton            38.87N 91.94W
04/17/2026                   Callaway           MO   Trained Spotter

            Stoplights at Bluff and Industrial Ave
            damaged, as is the sign for the Sonic on
            North Bluff Street and numerous street
            lights.

&&

LSJ

Preliminary Local Storm Report
National Weather Service St Louis MO
251 PM CDT Sat Apr 18 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0250 PM     Tornado          3 WNW Treloar           38.66N 91.24W
04/18/2026                   Warren             MO   NWS Storm Survey

            NWS survey team found an EF-1 tornado mostly
            south of Pinckney. The tornado produced tree
            damage. It had a path length of 1.63 miles
            and was on the ground for approximately 2
            minutes.

&&

LSJ

Preliminary Local Storm Report
National Weather Service St Louis MO
257 PM CDT Sat Apr 18 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0422 PM     Tstm Wnd Dmg     1 NNE Griggsville       39.72N 90.72W
04/17/2026                   Pike               IL   Broadcast Media

            Part of a metal roof was torn off of a farm
            outbuilding. Debris was found at least a
            half mile away.

&&

LSJ

Preliminary Local Storm Report
National Weather Service St Louis MO
403 PM CDT Sat Apr 18 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0929 PM     Tornado          3 WNW Treloar           38.66N 91.24W
04/17/2026                   Warren             MO   NWS Storm Survey

            Corrects previous tornado report from 3 WNW
            Treloar. NWS survey team found an EF-1
            tornado mostly south of Pinckney. The
            tornado produced tree damage. It had a path
            length of 1.63 miles and was on the ground
            for approximately 2 minutes.

&&

Delia