Severe Thunderstorm Warning 245, NWS St. Louis, MO

669 
WWUS53 KLSX 220751
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
251 AM CDT Sat Aug 22 2026

ILC117-135-220801-
/O.CAN.KLSX.SV.W.0245.000000T0000Z-260822T0845Z/
Macoupin IL-Montgomery IL-
251 AM CDT Sat Aug 22 2026

...SEVERE THUNDERSTORM WARNING IS CANCELLED FOR SOUTHERN MONTGOMERY
COUNTY IN SOUTH CENTRAL ILLINOIS AND SOUTHEASTERN MACOUPIN COUNTY IN
SOUTHWESTERN ILLINOIS...

The storms which prompted the warning have moved out of the area.
Therefore, the warning has been cancelled.

&&

LAT...LON 3897 8987 3890 8936 3890 8896 3848 8872
      3847 8914 3850 8914 3852 8935 3847 8948
      3847 8961 3842 8970 3866 8971 3866 8973
TIME...MOT...LOC 0738Z 344DEG 27KT 3889 8907 3887 8941 3895 8976

$$


ILC005-027-051-119-121-220845-
/O.CON.KLSX.SV.W.0245.000000T0000Z-260822T0845Z/
Bond IL-Clinton IL-Fayette IL-Madison IL-Marion IL-
251 AM CDT Sat Aug 22 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 AM CDT FOR
SOUTHERN BOND, CLINTON, SOUTHWESTERN FAYETTE AND MARION COUNTIES IN
SOUTH CENTRAL ILLINOIS AND EASTERN MADISON COUNTY IN SOUTHWESTERN
ILLINOIS...

At 251 AM CDT, severe thunderstorms were located along a line from
near Patoka to over Alhambra, or along a line from 13 miles north of
Salem to 7 miles north of Highland, moving south at 30 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail
         damage to roofs, siding, windows, and vehicles. Expect wind
         damage to roofs, siding, and trees.

Locations impacted include...
  Greenville, Worden, Pocahontas, Highland, Marine, Carlyle, St.
  Rose, Odin, Salem, Sandoval, Beckemeyer, Breese, Aviston, Central
  City, Trenton, Centralia, Germantown, Wamac, New Baden and Albers.

This includes the following State Parks...
Carlyle Lake State Fish and Wildlife Area and Eldon Hazlet State
Recreation Area.

This includes the following highways...
Interstate 64 in Illinois near exit 34. Interstate 55 in Illinois
near exit 33. Interstate 70 in Illinois between exits 24 and 45.
Interstate 57 in Illinois between exits 109 and 127.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from
windows. These storms are capable of producing damaging winds and
large hail.

&&

LAT...LON 3897 8987 3890 8936 3890 8896 3848 8872
      3847 8914 3850 8914 3852 8935 3847 8948
      3847 8961 3842 8970 3866 8971 3866 8973
TIME...MOT...LOC 0738Z 344DEG 27KT 3889 8907 3887 8941 3895 8976

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Carney

644 
WWUS53 KLSX 220818
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
318 AM CDT Sat Aug 22 2026

ILC005-051-220828-
/O.CAN.KLSX.SV.W.0245.000000T0000Z-260822T0845Z/
Bond IL-Fayette IL-
318 AM CDT Sat Aug 22 2026

...SEVERE THUNDERSTORM WARNING IS CANCELLED FOR SOUTHERN BOND AND
SOUTHWESTERN FAYETTE COUNTIES...

The storms which prompted the warning have moved out of the area.
Therefore, the warning has been cancelled.

&&

LAT...LON 3881 8971 3879 8960 3874 8960 3873 8887
      3848 8872 3847 8914 3850 8914 3852 8935
      3847 8948 3848 8957 3847 8961 3842 8970
TIME...MOT...LOC 0751Z 344DEG 27KT 3880 8903 3877 8937 3885 8973

$$


ILC027-119-121-220845-
/O.CON.KLSX.SV.W.0245.000000T0000Z-260822T0845Z/
Clinton IL-Madison IL-Marion IL-
318 AM CDT Sat Aug 22 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 AM CDT FOR
CLINTON AND SOUTHERN MARION COUNTIES IN SOUTH CENTRAL ILLINOIS AND
SOUTHEASTERN MADISON COUNTY IN SOUTHWESTERN ILLINOIS...

At 318 AM CDT, severe thunderstorms were located along a line from 5
miles southeast of Salem to near Trenton, or along a line from 5
miles southeast of Salem to 6 miles south of Highland, moving south
at 35 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to
         roofs, siding, and trees.

Locations impacted include...
  Highland, Boulder, Fairman, Carlyle, St. Rose, Shattuc, Salem,
  Sandoval, Beckemeyer, Odin, Breese, Central City, Aviston,
  Centralia, Germantown, Wamac, Trenton, Albers and New Baden.

This includes the following State Parks...
Eldon Hazlet State Recreation Area.

This includes the following highways...
Interstate 64 in Illinois near exit 34. Interstate 70 in Illinois
near exit 30. Interstate 57 in Illinois between exits 109 and 116.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from
windows. These storms are capable of producing damaging winds and
large hail.

&&

LAT...LON 3881 8971 3879 8960 3874 8960 3873 8887
      3848 8872 3847 8914 3850 8914 3852 8935
      3847 8948 3848 8957 3847 8961 3842 8970
TIME...MOT...LOC 0751Z 355DEG 30KT 3880 8890 3874 8915 3873 8942 3879
8958 3889 8971

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Carney

041 
WWUS53 KLSX 220842
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
342 AM CDT Sat Aug 22 2026

ILC027-119-121-220852-
/O.EXP.KLSX.SV.W.0245.000000T0000Z-260822T0845Z/
Clinton IL-Madison IL-Marion IL-
342 AM CDT Sat Aug 22 2026

...SEVERE THUNDERSTORM WARNING WILL EXPIRE AT 345 AM CDT FOR CLINTON
AND SOUTHERN MARION COUNTIES IN SOUTH CENTRAL ILLINOIS AND
SOUTHEASTERN MADISON COUNTY IN SOUTHWESTERN ILLINOIS...

The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.

&&

LAT...LON 3881 8971 3879 8960 3874 8960 3873 8887
      3848 8872 3847 8914 3850 8914 3852 8935
      3847 8948 3848 8957 3847 8961 3842 8970
TIME...MOT...LOC 0818Z 355DEG 30KT 3858 8887 3852 8913 3851 8940 3857
8955 3867 8969

$$

Carney

Area Forecast Discussion
National Weather Service St Louis MO
1039 PM CDT Fri Aug 21 2026

.KEY MESSAGES...

- Seasonably cool late summer temperatures are expected this
  weekend into next week with few opportunities for rain.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 210 PM CDT Fri Aug 21 2026

Currently a ridge of high pressure over the Intermountain West
has spread hot and dry conditions out into the Plains. A trough
centered over Hudson Bay has extended its influence southward
into the Great Lakes, with this trough expected to continue
pushing into the Great Lakes and New England over the coming
days. A leading shortwave trough is pushing through Wisconsin
toward Chicago this afternoon, with a cold front sliding
southward behind it. There are two primary areas of convection
expected in the next 12 to 24 hours along this front:

The first is closer to the shortwave trough tracking into
northern Illinois. Here some modest moisture convergence aided
by lift from the shortwave trough will lead to scattered
thunderstorms potentially merging into a broader complex pushing
southeast overnight. It is likely that these storms track to
the east of our forecast area, but there's an outside chance (20
percent) that they do move through our far eastern counties
overnight. While there is some severe weather threat with this,
the threat will be greatest in the evening hours closer to the
core of the thunderstorm complex. The threat locally will be
considerably lower and later in the night.

The second is to the west over Nebraska and Kansas. Here a low
level jet this evening will send modest moisture northward
toward the front and trigger another thunderstorm complex to
develop. This tracks southeast potentially into western Missouri
overnight, but is unlikely (less than 10 percent) to make it
into our forecast area.

The most likely scenario for us tonight will be a subtle passage
of the cold front overnight, with winds turning out of the north
by morning. Expect a mostly sunny day behind the front on
Saturday. Despite cold advection, deep post-frontal mixing will
ensure it's another warm day in the mid to perhaps upper 80s.
That deep mixing, though, is expected to mix in some drier air
from aloft. We've deliberately included more of the higher
resolution guidance in the forecast to reflect this drying. Some
guidance has dewpoints falling well into the 50s with a
corresponding increase in temperature.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 210 PM CDT Fri Aug 21 2026

As we go through the weekend, the trough spins into
southeastern Canada while the ridge expands its influence
eastward into the Rockies and Great Plains. Surface high
pressure moving in behind tonight's front will ensure that our
area remains more under the influence of the cooler air mass
from the trough despite rising heights aloft. Highs only reach
the low 80s with lows in the low 60s or even upper 50s at times.

As the ridge nudges eastward our area will become better
situated to have some effects from ridge running shortwave
troughs, what we sometimes call the "ring of fire" of
thunderstorm complexes rotating around a ridge. At first, low
level moisture is pretty limited due to northerly low level flow
near the Gulf, but over the next few days better moisture does
eventually lift northward into the Southern Plains. It has more
difficulty moving eastward, though, as the influence of the
surface high moving into the western Great Lakes and Ohio Valley
remains strong. We've seen a growing consensus in guidance at
this point for the focus of convection Sunday into Monday to
stay just to our southwest along with the effective warm front.
Some cloud cover from this activity to our west may actually
help to hold temperatures down even further on Monday,
potentially in the 70s. Meanwhile on the other side of the warm
front the heat is on with temperatures potentially near 100.

The next more substantial shortwave trough tracks through the
northwest flow on Wednesday, but it's not clear we ever get into
the warm, moist air by then. So despite the passage of another
weak cold front, we may not get any rain out of it. NBM POP
remains low (less than 20 percent), and most of the low
resolution ensemble guidance keeps the focus for precipitation
to our south where the better moisture exists or to our north
where the core of the upper wave will be. Additional shortwave
troughs have some potential (20 percent or less) to bring
additional rounds of showers and storms through the end of the
week, but confidence gets lower with time on when and where
those waves will track. There is a general consensus, though,
that the ridge eventually expands far enough east that we
eventually get in on the warmer weather again. NBM probability
of 90 degree heat increases to about 30 percent by Friday.

&&

.AVIATION /00Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1036 PM CDT Fri Aug 21 2026

Mainly VFR flight conditions are expected through the TAF period
at all local terminals as a dry cold front drops through the
area during the morning hours and causes winds to shift to out
of the north-northwest. There is a threat of fog at KSUS, but
the front's passage may mitigate this. If fog does develop, dry
air and the wind shift with the front will help quickly
dissipate it by around sunrise.

&&

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

&&

SHORT TERM...Kimble
LONG TERM...Kimble
AVIATION...Elmore