Severe Thunderstorm Warning 42, NWS St. Louis, MO

796 
WWUS53 KLSX 140439
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
1139 PM CDT Mon Apr 13 2026

MOC135-140500-
/O.CON.KLSX.SV.W.0042.000000T0000Z-260414T0500Z/
Moniteau MO-
1139 PM CDT Mon Apr 13 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CDT
FOR MONITEAU COUNTY...

At 1139 PM CDT, a severe thunderstorm was located near High Point, or
7 miles southwest of California, moving east at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
  Tipton, Latham, Clarksburg, High Point, California, Kliever,
  McGirk, Jamestown, Lupus and Sandy Hook.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from
windows. This storm is capable of producing damaging winds.

&&

LAT...LON 3877 9241 3875 9241 3874 9240 3843 9250
      3855 9277 3855 9278 3868 9278 3868 9262
      3869 9262 3892 9250 3890 9247 3887 9248
      3887 9247 3886 9246 3883 9244 3882 9242
      3882 9239 3881 9238 3879 9238 3878 9239
TIME...MOT...LOC 0411Z 270DEG 32KT 3855 9294

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Carney

130 
WWUS53 KLSX 140452
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
1152 PM CDT Mon Apr 13 2026

MOC135-140502-
/O.EXP.KLSX.SV.W.0042.000000T0000Z-260414T0500Z/
Moniteau MO-
1152 PM CDT Mon Apr 13 2026

...SEVERE THUNDERSTORM WARNING WILL EXPIRE AT MIDNIGHT CDT FOR
MONITEAU COUNTY...

The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However, gusty
winds and heavy rain are still possible with this thunderstorm.

&&

LAT...LON 3877 9241 3875 9241 3874 9240 3843 9250
      3855 9277 3855 9278 3868 9278 3868 9262
      3869 9262 3892 9250 3890 9247 3887 9248
      3887 9247 3886 9246 3883 9244 3882 9242
      3882 9239 3881 9238 3879 9238 3878 9239
TIME...MOT...LOC 0439Z 270DEG 32KT 3855 9262

$$

Carney

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1111 PM CDT Mon Apr 13 2026

.KEY MESSAGES...

- Severe thunderstorms are possible Tuesday night and again Wednesday
  afternoon into evening. The better chance for severe weather
  exists on Wednesday. Large hail and damaging winds will be the
  primary threats each day.

- A potent cold front will pass through the region late this week, bringing
  another chance for strong to severe thunderstorms and an end to
  the unseasonable warmth.

&&

.SHORT TERM...  (Through Late Tuesday Night)
Issued at 157 PM CDT Mon Apr 13 2026

Water vapor imagery shows an upper-mid level longwave trough over
the northwestern third of the CONUS with an upper-low level ridge
dominating the remainder of the country. The Mid-Mississippi
Valley's weather is being influenced by the northwestern portion of
ridge as seen by strong, deep southwest flow throughout the
atmospheric column. We're seeing this at the surface in the form of
temperatures in the 80s, which is 20 degrees above normal for mid-
April. Gulf moisture is also being advected in along the
southwesterly flow, as characterized by dewpoints in the 60s.
Needless to say, there is an abundance of warmth and moisture in the
region. This translates to an abundance of instability as well,
which leads us into Tuesday and Wednesday's severe potential.

The bottom line for Tuesday is that the potential for severe
thunderstorms in our area is low. Despite being located within an
open warm sector and an 80% HREF probability of having 2500+ J/kg of
SBCAPE in place, a strong capping inversion is expected to keep
convective initiation at bay through the afternoon. A lack of any
forcing or mid and upper level lift supports at least mostly dry
weather as well. Instead, supercells are expected to fire off a
dryline in Kansas southward through Texas in the afternoon and
become severe as they drive northeast. By the time they reach
central Missouri in the evening, daytime instability will be quickly
waning and CIN quickly growing. If the mass of thunderstorms is
still severe by the time it arrives, the increasingly unfavorable
environment it moves into will ensure it won't stay severe for long.
If any thunderstorm does remain severe, large hail and damaging
winds will be the primary threats.

A strengthening low-level jet Tuesday night will keep ongoing
convection from eroding completely and/or spark new initiation. None
of this is expected to be severe, but it may impact the potential
for severe thunderstorms on Wednesday especially if it lasts well
into the morning.

Jaja

&&

.LONG TERM...  (Wednesday through Next Monday)
Issued at 157 PM CDT Mon Apr 13 2026

By 1pm Wednesday, the longwave trough currently over the western
CONUS will be centered in the High Plains. A jet streak will extend
northeastward through the Southern Plains and into the Great Lakes
region, skimming our CWA along its extent. Though the best upper
level forcing will exist to our northwest, we'll still be in the
right entrance region of the jet streak and will be able to take
advantage of the more robust upper level support. The same can be
said in the mid-levels where forcing increases ahead of an incoming
shortwave. In the low-levels, a surface cyclone will be pushing
northeast from Nebraska into the Upper Midwest, dragging a cold
front into northwestern Missouri to serve as forcing for ascent.
This will all make for a much better set-up than Tuesday. The only
potentially mitigating factor will be instability. More
specifically, how well the boundary layer will recover after Tuesday
night's/Wednesday morning's low-level jet driven convection. The
latest LREF shows only up to 1000 J/kg of SBCAPE in place by 1pm.
This is a much lower value than Tuesday's 2500+ J/kg, but with so
much support at all levels, it shouldn't matter. Effective bulk
shear will also be in the 35-45 kt range, which is more than enough
to support severe weather even given the lower instability. Shear
vectors are forecast to be about 45 degrees off of the cold front.
This may result in discrete thunderstorms capable of large hail and
damaging winds initially before congealing into a line or multi-
cell mass. Minor shifts in the bulk shear vectors may change storm
mode drastically. More than 45 degrees and supercells will be
favored. Less than 45 degrees and a QLCS will likely develop
faster with damaging winds being the primary threat.

As mentioned, thunderstorms will weaken in the hours after sunset.
Two mid-level shortwaves, one in the Upper Midwest and another in
the Mid-South, will pass Wednesday night into Thursday, and another
low-level jet will ramp up along and ahead of the cold front. These
features will offer continued support for ascent, and will keep non-
severe convection going until the Mid-South shortwave exits late
Thursday. The cold front is not expected to clear the area entirely,
but will instead buckle northward as a warm front late Thursday. A
lack of cold air behind the front will make its passage and return
basically unnoticeable as highs reach the widespread upper 70s
and low 80s again Thursday. A much more potent cold front will
drive through the region late Friday/early Saturday and will bring
a real rush of cool air into the area. Although there's still
uncertainty regarding how cool we get, the NBM 75th percentile
high temperature forecast for KSTL on Sunday is only 71 degrees.
There is another chance of thunderstorms on Friday ahead of the
cold front with severe weather possible again. The potential for
severe weather will rely on the timing of the cold front, which at
this point is still very uncertain.

Jaja

&&

.AVIATION...  (For the 06z TAFs through 06z Tuesday Night)
Issued at 1102 PM CDT Mon Apr 13 2026

A complex of showers and thunderstorms has track from eastern
Kansas into central Missouri late this evening. The activity is
expected to make it into KCOU just before midnight and near KJEF
around 06z. The strongest thunderstorms have produced wind gusts
up to 70 mph to the west of the TAF sites, though general
weakening is expected with eastward movement. Locally heavy rain
and gusty winds are possible with these thunderstorms, through
approximately 08z.

Thunderstorms should continue to weaken as they approach the
Mississippi River late tonight. Cloud base remain above VFR level
for the most part with localize, briefing dips to MVFR under the
strongest cells. MVFR will become less likely as thunderstorms
remain elevated and weaken overnight. Gusty conditions are
expected to continue much of the time, being more prevalent during
the daylight hours after diurnal mixing resumes late Tuesday
morning. Isolated to widely scattered showers are possible Tuesday
afternoon, but will be hit-or-miss. This was not included in the
prevailing group with the high degree of uncertainty at any given
terminal. Chances for rain increase late Tuesday night with
showers and an isolated thunderstorm. However, widespread
thunderstorms are not expected with VFR persisting through the end
of the period.

Maples

&&

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

WFO LSX

Hazardous Weather Outlook
National Weather Service St Louis MO
226 PM CDT Mon Apr 13 2026

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-141930-
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-
226 PM CDT Mon Apr 13 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...Tuesday through Sunday.

There is a chance of thunderstorms each day through Saturday night.

Severe thunderstorms are possible Tuesday night and again Wednesday
afternoon into Wednesday evening.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Jaja