River Flood Warning 38, NWS St. Louis, MO

868 
WGUS83 KLSX 281518
FLSLSX

Flood Statement
National Weather Service St Louis MO
1018 AM CDT Tue Apr 28 2026

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

  Mid Fork Salt River near Holliday.

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

MOC137-281630-
/O.CAN.KLSX.FL.W.0038.000000T0000Z-260428T1518Z/
/PMZM7.1.ER.000000T0000Z.000000T0000Z.000000T0000Z.NO/
1018 AM CDT Tue Apr 28 2026

...FLOOD WARNING IS CANCELLED...

The Flood Warning is cancelled for
  the Mid Fork Salt River near Holliday.

* ADDITIONAL DETAILS...
  - At 10:00 AM CDT Tuesday the stage was 15.5 feet.
  - Forecast...The river is expected to rise to a crest of 15.5 feet
    this afternoon.



&&


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

Mid Fork Salt River
 Holliday          17.0    15.5    12.0  7.5   6.9   6.1   5.7



&&

LAT...LON 3958 9229 3959 9226 3955 9222 3954 9212
      3950 9201 3950 9196 3947 9196 3949 9210
      3951 9215 3951 9220 3953 9224


$$

Fuchs

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
647 AM CDT Mon Apr 27 2026

.KEY MESSAGES...

- While periods of storms are expected through Monday morning, the most
  potent thunderstorms will occur this afternoon and evening.

- Thunderstorms this afternoon and evening will be capable of
  damaging wind gusts, large hail, and strong tornadoes.

- A period of cool, calm weather is expected mid-week through the
  weekend.

&&

.SHORT TERM... (Through Tuesday Night)
Issued at 155 AM CDT Mon Apr 27 2026

Storms across southeastern Missouri continue to butt up against an
instability gradient draped from north to south across Missouri.
The warm air advection feeding these storms will also push greater
instability slowly northeastward through this morning, though
propagation vectors will favor convection continuing to move east-
southeastward generally away from the CWA or into an unfavorable
environment. Additionally, the low-level jet refocusing across
Kansas will continue to support the downward trend in convection
across southeastern Missouri early this morning. Any linger storms
over the next couple of hours will be capable mainly of large hail,
though there is also a very low damaging wind and tornado threat for
storms that remain surface based.

Our attention turns to the storms over eastern Kansas that are
propagating eastward with the nose of the low-level jet. With the
nose of this low-level jet edging into northeastern Missouri later
this morning, the focus for these storms will spread into portions
of the CWA north of I-70. Vertical thermal profiles suggest that this
convection will be elevated, mitigating a threat of damaging wind
gusts and/or tornadoes. However, with around 40 kts of effective
shear and building MUCAPE, there is a low chance for isolated
instances of large hail.

How long this convection lingers is uncertain, although guidance
trends have been toward a lull in convective activity in the wake of
this convection and that associated with a cold front during the
late afternoon and evening. Ahead of the front, the warm sector
remains capped through much of the afternoon per a majority of
deterministic soundings. Although, any remnant outflow or
differential heating boundary from early day convection may serve as
enough of a forcing mechanism to spawn discrete convection during
the afternoon as lift from an approaching shortwave increases over
the region. If this convection does form, it will be in an
environment characterized by 2,000-2,500 J/kg of SBCAPE and roughly
50 kts of deep-layer shear. This will favor supercells capable of
all hazards, with long curved hodographs favoring strong tornadoes,
especially if storms are able to latch on to any remnant boundaries
across the CWA.

Where the environment isn't contaminated from earlier rounds of
convection, additional updrafts are expected along the cold front as
it enters the area 4-5pm. Forcing from the front paired with lift
from the shortwave will lead to numerous updrafts along the front.
While this will be occurring within a similar environment detailed
prior, the number of updrafts paired with them occurring along the
front may lead to destructive interactions and congealing into line
segments and/or clusters. While this will tend to limit a strong
tornado threat, storms will still be capable of all severe hazards.
Convection is expected to depart the CWA with the front by 9-10pm.

Even with the FROPA Monday evening, the threat for convection will
continue on Tuesday. Guidance consensus has the front stalling just
south of the CWA early Tuesday and then buckling northward as a
shortwave moves through the Central Plains and into the Midwest
through the day. This shortwave will send a subtle surface
reflection through the Mid South along the front, with a brief
period of warm air advection that will help force elevated
convection for areas mainly along and south of I-70. If the front
can move northward enough, shear profiles and instability amounts
favor supercells capable primarily of large hail across far
southeastern Missouri during the afternoon. Waning instability and
the front continuing southward will bring an end to rain chances
during the evening.

Elmore

&&

.LONG TERM... (Tuesday Night through Sunday)
Issued at 155 AM CDT Mon Apr 27 2026

Both deterministic guidance and ensemble clusters keep upper-level
troughing slowly moving eastward over the eastern CONUS through the
long range forecast period. This will maintain northwesterly flow
over the Middle Mississippi Valley through Saturday as several
rounds of high pressure pass through the region. As a result,
temperatures will run at or below climatological normals into the
weekend and mostly dry weather is expected.

Elmore

&&

.AVIATION...  (For the 12z TAFs through 12z Tuesday Morning)
Issued at 647 AM CDT Mon Apr 27 2026

Thunderstorms are expected at times throughout the day, impacting
all terminals. The greatest coverage of thunderstorms this morning
is expected to be across central, northeastern MO into west-central
IL impacting KCOU, KJEF, and KUIN, with lower confidence in
thunderstorms reaching the St. Louis metro terminals through early
afternoon. Another round of redevelopment will take place this
afternoon and evening with the greatest chance of severe
thunderstorms as well. These thunderstorms will be capable of hail,
strong winds, and some tornadoes. Trends will need to be monitored
for more significant terminal impacts beyond MVFR to IFR flight
conditions.

A cold front will pass through the region this evening, veering
southerly winds to northwesterly with drier conditions prevailing.
There is the potential for some post-frontal MVFR ceilings late
tonight into Tuesday morning, with the highest chance of impacts at
KUIN. However, given that confidence is low in impacts before the
end of the TAF period, VFR flight conditions are maintained for
now.

Pfahler

&&

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

WFO LSX

Hazardous Weather Outlook
National Weather Service St Louis MO
202 AM CDT Mon Apr 27 2026

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-280715-
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-
202 AM CDT Mon Apr 27 2026

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.

Periods of thunderstorms are expected through the day into this
evening. Thunderstorms this afternoon and evening will be capable of
large hail, damaging wind gusts, and tornadoes.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

There is a chance of thunderstorms Tuesday.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report wind damage, hail occurrence and
size, and tornado occurrence to NWS St. Louis.

Elmore

Preliminary Local Storm Report
National Weather Service St Louis MO
143 PM CDT Mon Apr 27 2026

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

0136 PM     Hail             2 WNW Town And Country  38.63N 90.51W
04/27/2026  E1.00 Inch       St. Louis          MO   Public

&&

MCF

Preliminary Local Storm Report
National Weather Service St Louis MO
217 PM CDT Mon Apr 27 2026

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

0148 PM     Hail             1 S Saint John          38.70N 90.35W
04/27/2026  M1.00 Inch       St. Louis          MO   Trained Spotter

            At Midland and I-170.

&&

Britt

Preliminary Local Storm Report
National Weather Service St Louis MO
223 PM CDT Mon Apr 27 2026

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

0221 PM     Hail             Glen Carbon             38.76N 89.97W
04/27/2026  M1.00 Inch       Madison            IL   Trained Spotter

&&

Carney

Preliminary Local Storm Report
National Weather Service St Louis MO
226 PM CDT Mon Apr 27 2026

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

0619 AM     Hail             2 W Saint Louis         38.65N 90.28W
04/27/2026  E1.00 Inch       St. Louis City     MO   Public

            Report from mPING: Quarter (1.00 in.).

0621 AM     Hail             2 SE Hillsdale          38.66N 90.27W
04/27/2026  E1.00 Inch       St. Louis City     MO   Public

            Report from mPING: Quarter (1.00 in.).

0642 AM     Hail             2 SE Hillsdale          38.66N 90.27W
04/27/2026  E1.25 Inch       St. Louis City     MO   Public

            Report from mPING: Half Dollar (1.25 in.).

0313 AM     Hail             1 NW Bismarck           37.78N 90.63W
04/27/2026  E1.50 Inch       St. Francois       MO   Public

            Report from mPING: Ping Pong Ball (1.50
            in.).

0318 AM     Hail             1 NW Bismarck           37.78N 90.63W
04/27/2026  E1.75 Inch       St. Francois       MO   Public

            Report from mPING: Golf Ball (1.75 in.).

0320 AM     Hail             1 NW Bismarck           37.78N 90.63W
04/27/2026  E2.00 Inch       St. Francois       MO   Public

            Report from mPING: Hen Egg (2.00 in.).

0329 AM     Hail             1 SW Desloge            37.87N 90.53W
04/27/2026  E1.00 Inch       St. Francois       MO   Public

            Report from mPING: Quarter (1.00 in.).

0329 AM     Hail             1 N Leadington          37.84N 90.48W
04/27/2026  E1.00 Inch       St. Francois       MO   Public

            Report from mPING: Quarter (1.00 in.).

0337 AM     Hail             1 NW Farmington         37.79N 90.43W
04/27/2026  M1.25 Inch       St. Francois       MO   Public

0339 AM     Hail             1 S Farmington          37.76N 90.42W
04/27/2026  E1.75 Inch       St. Francois       MO   Public

            Report from mPING: Golf Ball (1.75 in.).

0358 AM     Hail             5 E Farmington          37.77N 90.34W
04/27/2026  E1.50 Inch       St. Francois       MO   Public

            Report from mPING: Ping Pong Ball (1.50
            in.).

0418 AM     Hail             4 SE Farmington         37.74N 90.36W
04/27/2026  E2.00 Inch       St. Francois       MO   Public

            Report from mPING: Hen Egg (2.00 in.).

1225 PM     Hail             2 S Harvester           38.72N 90.59W
04/27/2026  E1.00 Inch       St. Charles        MO   Public

            Report from mPING: Quarter (1.00 in.).

&&

Preliminary Local Storm Report
National Weather Service St Louis MO
228 PM CDT Mon Apr 27 2026

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

0138 PM     Hail             1 E Clarkson Valley     38.63N 90.58W
04/27/2026  E1.25 Inch       St. Louis          MO   Public

0134 PM     Hail             1 SW Bridgeton          38.75N 90.44W
04/27/2026  E1.50 Inch       St. Louis          MO   Public

            Report from mPING: Ping Pong Ball (1.50
            in.).

&&

Preliminary Local Storm Report
National Weather Service St Louis MO
237 PM CDT Mon Apr 27 2026

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

0221 PM     Hail             4 SE Jonesburg          38.82N 91.26W
04/27/2026  E1.00 Inch       Warren             MO   Public

&&