Alert archive / Illinois / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 128, NWS St. Louis, MO

April 27, 20264 counties in Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 27, 2026, 8:30 PM CDT for 4 counties in Illinois. It was in force for 37 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Apr 27, 2026, 8:30 PM CDT (01:30 UTC)
Expired
Apr 27, 2026, 9:07 PM CDT
In force
37 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Tornado
Possible
Damage threat
Considerable
Hail
1.0 in
Wind
70.0 mph

Counties Clinton County, IL, Fayette County, IL, Marion County, IL, Washington County, IL

The radar

The Evansville,IN radar (KVWX), 119 km from the middle of the area, began a volume at 01:34 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Apr 27, 8:30 PM CDTTSTM WND DMGCentralia, ILpower lines down all over town. time estimated.
Apr 27, 8:35 PM CDTTSTM WND DMGCentralia, ILPower poles and tree damage.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 2 storm reports to this severe thunderstorm warning; the first came 0 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 27, 12:50 PM CDTTornado WatchSPC9 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 1.5 hours before the alert went out and 167 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2026-04-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2026-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -1 square meters per square second.1939587897Sfc1 km3 km6 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1082 m above ground
0-6 km bulk shear
76 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
-57 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

708 
WUUS53 KLSX 280130
SVRLSX
ILC027-051-121-189-280215-
/O.NEW.KLSX.SV.W.0128.260428T0130Z-260428T0215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
830 PM CDT Mon Apr 27 2026

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Northeastern Clinton County in south central Illinois...
  Southern Fayette County in south central Illinois...
  Marion County in south central Illinois...
  Northeastern Washington County in south central Illinois...

* Until 915 PM CDT.

* At 830 PM CDT, severe thunderstorms were located along a line from
  near Patoka to over Wamac, or along a line from 13 miles south of
  Vandalia to near Centralia, moving east at 50 mph.

  HAZARD...70 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect considerable
           tree damage. Wind damage is also likely to mobile homes,
           roofs, and outbuildings.

* Locations impacted include...
  Boulder, Shattuc, Wamac, Central City, Centralia, Junction City,
  Sandoval, Fairman, Patoka, Odin, Salem, Tonti, Kinmundy, Farina,
  Iuka, Omega, Stephen Forbes Station, Helm and La Clede.

This includes Interstate 57 in Illinois between exits 109 and 135.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Anyone outdoors should move to shelter inside a well-built structure
and stay away from windows. These storms are capable of producing
widespread damaging winds and large hail.

Tornadoes can develop quickly from severe thunderstorms. Seek shelter
immediately in an interior room on the lowest floor of a well-built
structure.

A Tornado Watch remains in effect until 900 PM CDT for a portion of
south central Illinois.

&&

LAT...LON 3874 8923 3882 8924 3891 8881 3891 8869
      3872 8870 3848 8870 3848 8897 3847 8904
      3847 8920
TIME...MOT...LOC 0130Z 267DEG 44KT 3879 8916 3866 8915 3848 8914

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Elmore
5 follow-up statements
355 
WWUS53 KLSX 280142
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
842 PM CDT Mon Apr 27 2026

ILC027-189-280152-
/O.CAN.KLSX.SV.W.0128.000000T0000Z-260428T0215Z/
Clinton IL-Washington IL-
842 PM CDT Mon Apr 27 2026

...SEVERE THUNDERSTORM WARNING IS CANCELLED FOR NORTHEASTERN CLINTON
AND NORTHEASTERN WASHINGTON COUNTIES IN SOUTH CENTRAL ILLINOIS...

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

&&

LAT...LON 3874 8915 3882 8915 3891 8881 3891 8869
      3880 8870 3848 8870 3848 8897 3847 8901
      3847 8914 3874 8914
TIME...MOT...LOC 0130Z 267DEG 44KT 3879 8916 3866 8914 3848 8914

$$


ILC051-121-280215-
/O.CON.KLSX.SV.W.0128.000000T0000Z-260428T0215Z/
Fayette IL-Marion IL-
842 PM CDT Mon Apr 27 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CDT FOR
SOUTHEASTERN FAYETTE AND MARION COUNTIES IN SOUTH CENTRAL ILLINOIS...

At 842 PM CDT, severe thunderstorms were located along a line from 7
miles west of Kinmundy to 10 miles south of Salem, or along a line
from 12 miles north of Salem to 10 miles east of Centralia, moving
east at 50 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable
         tree damage. Wind damage is also likely to mobile homes,
         roofs, and outbuildings.

Locations impacted include...
  Wamac, Central City, Centralia, Junction City, Sandoval, Fairman,
  Patoka, Odin, Salem, Tonti, Alma, Kell, Kinmundy, St. Peter,
  Farina, Iuka, Omega, Stephen Forbes Station, Helm and La Clede.

This includes Interstate 57 in Illinois between exits 109 and 135.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Anyone outdoors should move to shelter inside a well-built structure
and stay away from windows. These storms are capable of producing
widespread damaging winds and large hail.

Tornadoes can develop quickly from severe thunderstorms. Seek shelter
immediately in an interior room on the lowest floor of a well-built
structure.

&&

LAT...LON 3874 8915 3882 8915 3891 8881 3891 8869
      3880 8870 3848 8870 3848 8897 3847 8901
      3847 8914 3874 8914
TIME...MOT...LOC 0130Z 267DEG 44KT 3879 8916 3866 8914 3848 8914

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Elmore
447 
WWUS53 KLSX 280147
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
847 PM CDT Mon Apr 27 2026

ILC051-121-280215-
/O.CON.KLSX.SV.W.0128.000000T0000Z-260428T0215Z/
Fayette IL-Marion IL-
847 PM CDT Mon Apr 27 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CDT FOR
SOUTHEASTERN FAYETTE AND MARION COUNTIES IN SOUTH CENTRAL ILLINOIS...

At 847 PM CDT, severe thunderstorms were located along a line from
near Kinmundy to 9 miles west of Helm, or along a line from 13 miles
north of Salem to 11 miles southeast of Salem, moving east at 50 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable
         tree damage. Wind damage is also likely to mobile homes,
         roofs, and outbuildings.

Locations impacted include...
  Wamac, Central City, Centralia, Junction City, Sandoval, Odin,
  Walnut Hill, Salem, Tonti, Alma, Kell, Brubaker, Kinmundy, St.
  Peter, Farina, Iuka, Omega, Stephen Forbes Station, Helm and La
  Clede.

This includes Interstate 57 in Illinois between exits 109 and 135.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Anyone outdoors should move to shelter inside a well-built structure
and stay away from windows. These storms are capable of producing
widespread damaging winds and large hail.

Tornadoes can develop quickly from severe thunderstorms. Seek shelter
immediately in an interior room on the lowest floor of a well-built
structure.

A Tornado Watch remains in effect until 1100 PM CDT for a portion of
south central Illinois.

&&

LAT...LON 3874 8905 3885 8899 3891 8881 3891 8869
      3886 8869 3880 8870 3848 8870 3848 8899
      3847 8914 3859 8914
TIME...MOT...LOC 0142Z 267DEG 44KT 3880 8897 3866 8896 3848 8895

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Elmore
562 
WWUS53 KLSX 280153
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
853 PM CDT Mon Apr 27 2026

ILC051-121-280215-
/O.CON.KLSX.SV.W.0128.000000T0000Z-260428T0215Z/
Fayette IL-Marion IL-
853 PM CDT Mon Apr 27 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CDT FOR
SOUTHEASTERN FAYETTE AND MARION COUNTIES IN SOUTH CENTRAL ILLINOIS...

At 853 PM CDT, severe thunderstorms were located along a line from 10
miles east of Stephen Forbes Station to near Helm, or along a line
from 22 miles northeast of Salem to 14 miles southeast of Salem,
moving east at 55 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable
         tree damage. Wind damage is also likely to mobile homes,
         roofs, and outbuildings.

Locations impacted include...
  Salem, Selmaville, Alma, Kinmundy, Walnut Hill, Brubaker, Farina,
  Cartter, Omega, Kell, Stephen Forbes Station, Iuka, La Clede and
  Helm.

This includes Interstate 57 in Illinois between exits 109 and 116...
and near exit 135.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Anyone outdoors should move to shelter inside a well-built structure
and stay away from windows. These storms are capable of producing
widespread damaging winds and large hail.

Tornadoes can develop quickly from severe thunderstorms. Seek shelter
immediately in an interior room on the lowest floor of a well-built
structure.

A Tornado Watch remains in effect until 1100 PM CDT for a portion of
south central Illinois.

&&

LAT...LON 3847 8914 3882 8883 3891 8869 3883 8870
      3848 8870 3848 8899 3847 8907
TIME...MOT...LOC 0147Z 269DEG 46KT 3877 8869 3863 8877 3849 8887

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Elmore
713 
WWUS53 KLSX 280159
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
859 PM CDT Mon Apr 27 2026

ILC051-280209-
/O.CAN.KLSX.SV.W.0128.000000T0000Z-260428T0215Z/
Fayette IL-
859 PM CDT Mon Apr 27 2026

...SEVERE THUNDERSTORM WARNING IS CANCELLED FOR SOUTHEASTERN FAYETTE
COUNTY...

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

A Tornado Watch remains in effect until 1100 PM CDT for a portion of
south central Illinois.

&&

LAT...LON 3847 8908 3883 8870 3848 8870 3848 8899
      3847 8904
TIME...MOT...LOC 0153Z 269DEG 46KT 3878 8859 3863 8867 3849 8877

$$


ILC121-280215-
/O.CON.KLSX.SV.W.0128.000000T0000Z-260428T0215Z/
Marion IL-
859 PM CDT Mon Apr 27 2026

...SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CDT FOR
EASTERN MARION COUNTY IN SOUTH CENTRAL ILLINOIS...

At 859 PM CDT, severe thunderstorms were located along a line from 15
miles east of Stephen Forbes Station to over Helm, or along a line
from 27 miles east of Salem to 18 miles southeast of Salem, moving
east at 55 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable
         tree damage. Wind damage is also likely to mobile homes,
         roofs, and outbuildings.

Locations impacted include...
  Walnut Hill, Cartter, Omega, Kell, Stephen Forbes Station, Iuka and
  Helm.

This includes Interstate 57 in Illinois near exit 109.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Anyone outdoors should move to shelter inside a well-built structure
and stay away from windows. These storms are capable of producing
widespread damaging winds and large hail.

Tornadoes can develop quickly from severe thunderstorms. Seek shelter
immediately in an interior room on the lowest floor of a well-built
structure.

A Tornado Watch remains in effect until 1100 PM CDT for a portion of
south central Illinois.

&&

LAT...LON 3847 8908 3883 8870 3848 8870 3848 8899
      3847 8904
TIME...MOT...LOC 0153Z 269DEG 46KT 3878 8859 3863 8867 3849 8877

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Elmore
814 
WWUS53 KLSX 280207
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
907 PM CDT Mon Apr 27 2026

ILC121-280217-
/O.CAN.KLSX.SV.W.0128.000000T0000Z-260428T0215Z/
Marion IL-
907 PM CDT Mon Apr 27 2026

...SEVERE THUNDERSTORM WARNING IS CANCELLED FOR EASTERN MARION COUNTY
IN SOUTH CENTRAL ILLINOIS...

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

&&

LAT...LON 3847 8908 3883 8870 3848 8870 3848 8899
      3847 8904
TIME...MOT...LOC 0159Z 269DEG 46KT 3878 8849 3863 8858 3849 8868

$$

Elmore

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS St. Louis, MO wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 27, 6:54 PM CDT, 1 hour 36 minutes earlier. Its key messages:

  • While periods of storms are expected through Monday morning, the most potent thunderstorms will occur through early evening.
  • Thunderstorms this 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.
Area forecast discussion, Apr 27, 6:54 PM CDT, 1 hour 36 minutes before
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
654 PM CDT Mon Apr 27 2026

.KEY MESSAGES...

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

- Thunderstorms this 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 456 PM CDT Mon Apr 27 2026

(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...WEDNESDAY THROUGH MONDAY/...
Issued at 456 PM CDT Mon Apr 27 2026

(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 00z TAFs through 00z Tuesday Evening)
Issued at 654 PM CDT Mon Apr 27 2026

Ongoing line of strong to severe thunderstorms moving through the
STL Metro area at the start of this TAF period. Storms along this
line will be capable of damaging winds, large hail and tornadoes.
The line will gradually move east-southeast and exit the forecast
area by 03-04Z. Remainder of the period will generally see calmer
conditions with VFR cloud cover. However, another round of showers
and isolated TSRA will spread into the forecast area from the
southwest after 18-20Z Tuesday. This will mostly impact COU/JEF
during this TAF period, but could spread MVFR ceilings into the
SUS/STL vicinity after 28/23Z.

SPECIFICS FOR KSTL: Broken line of +TSRA will bring a potential
for erratic, possibly damaging winds to STL through 01Z-02Z. Radar
trends show the strongest thunderstorm cores skirting around the
terminal, though additional development is possible within the
next hour. After TSRA exit to the east, VFR conditions dominate
until late in this TAF period (after 29/02Z) when MVFR conditions
could move in from the southwest.

WFO LSX

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch until 9 PM CDT this evening for Audrain MO-Boone MO-
     Callaway MO-Cole MO-Franklin MO-Gasconade MO-Jefferson MO-
     Lincoln MO-Moniteau MO-Montgomery MO-Osage MO-Pike MO-Saint
     Charles MO-Saint Louis City MO-Saint Louis MO-Warren MO.

IL...Flood Watch until 9 PM CDT this evening for Bond IL-Calhoun IL-
     Clinton IL-Fayette IL-Greene IL-Jersey IL-Macoupin IL-
     Madison IL-Marion IL-Monroe IL-Montgomery IL-Saint Clair IL-
     Washington IL.

&&

WFO LSX
Hazardous weather outlook, Apr 27, 2:02 AM CDT, 18 hours 28 minutes before
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

In the hours before

Local storm report, Apr 27, 7:33 PM CDT, 57 minutes before
Preliminary Local Storm Report
National Weather Service St Louis MO
733 PM CDT Mon Apr 27 2026

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

0710 PM     Tstm Wnd Dmg     Florissant              38.80N 90.32W
04/27/2026                   St. Louis          MO   Public

            4 buildings collapsed in Florissant.

&&
Local storm report, Apr 27, 7:35 PM CDT, 55 minutes before
Preliminary Local Storm Report
National Weather Service St Louis MO
735 PM CDT Mon Apr 27 2026

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

0730 PM     Tstm Wnd Gst     Hamel                   38.89N 89.84W
04/27/2026  E70 MPH          Madison            IL   Public

&&
Local storm report, Apr 27, 7:44 PM CDT, 46 minutes before
Preliminary Local Storm Report
National Weather Service St Louis MO
744 PM CDT Mon Apr 27 2026

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

0735 PM     Tstm Wnd Dmg     2 SE Belleville         38.51N 89.98W
04/27/2026                   St. Clair          IL   Emergency Mngr

            *** 3 INJ ***
            tree onto a house with potential injuries.

&&
Local storm report, Apr 27, 7:47 PM CDT, 43 minutes before
Preliminary Local Storm Report
National Weather Service St Louis MO
747 PM CDT Mon Apr 27 2026

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

0558 PM     Hail             1 N Jerseyville         39.14N 90.32W
04/27/2026  E1.00 Inch       Jersey             IL   Public

            Report from mPING: Quarter (1.00 in.).

0626 PM     Hail             2 S Gerald              38.36N 91.32W
04/27/2026  M1.25 Inch       Franklin           MO   Public

0644 PM     Hail             1 SW Pacific            38.47N 90.76W
04/27/2026  E1.00 Inch       Franklin           MO   Public

            Report from mPING: Quarter (1.00 in.).

0648 PM     Hail             2 E Gray Summit         38.49N 90.79W
04/27/2026  E1.25 Inch       Franklin           MO   Public

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

0654 PM     Hail             4 N Pacific             38.53N 90.75W
04/27/2026  E2.00 Inch       Franklin           MO   Public

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

0655 PM     Hail             2 NW Alton              38.93N 90.19W
04/27/2026  E1.50 Inch       Madison            IL   Public

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

0658 PM     Hail             2 SW Clarkson Valley    38.60N 90.62W
04/27/2026  E1.00 Inch       St. Louis          MO   Public

            Report from mPING: Quarter (1.00 in.).

0659 PM     Hail             1 NE Alton              38.91N 90.13W
04/27/2026  E1.00 Inch       Madison            IL   Public

            Report from mPING: Quarter (1.00 in.).

0700 PM     Hail             2 N Wood River          38.89N 90.08W
04/27/2026  E1.25 Inch       Madison            IL   Public

0707 PM     Hail             1 NW Bethalto           38.91N 90.06W
04/27/2026  E1.75 Inch       Madison            IL   Public

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

0708 PM     Hail             Bunker Hill             39.04N 89.95W
04/27/2026  E1.00 Inch       Macoupin           IL   Public

            Report from mPING: Quarter (1.00 in.).

0709 PM     Hail             1 S Bunker Hill         39.02N 89.95W
04/27/2026  E1.00 Inch       Macoupin           IL   Public

            Report from mPING: Quarter (1.00 in.).

0711 PM     Hail             3 W Carpenter           38.91N 89.95W
04/27/2026  E1.00 Inch       Madison            IL   Public

            Report from mPING: Quarter (1.00 in.).

0715 PM     Hail             3 W Carpenter           38.91N 89.95W
04/27/2026  E1.25 Inch       Madison            IL   Public

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

0718 PM     Hail             2 S Benld               39.06N 89.81W
04/27/2026  E1.00 Inch       Macoupin           IL   Public

            Report from mPING: Quarter (1.00 in.).

0720 PM     Hail             Staunton                39.01N 89.78W
04/27/2026  E1.00 Inch       Macoupin           IL   Public

            Report from mPING: Quarter (1.00 in.).

0733 PM     Hail             3 SE Columbia           38.43N 90.18W
04/27/2026  E1.00 Inch       Monroe             IL   Public

            Report from mPING: Quarter (1.00 in.).

&&
Local storm report, Apr 27, 7:50 PM CDT, 40 minutes before
Preliminary Local Storm Report
National Weather Service St Louis MO
750 PM CDT Mon Apr 27 2026

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

0720 PM     Tstm Wnd Dmg     1 E Richmond Heights    38.63N 90.31W
04/27/2026                   St. Louis City     MO   Emergency Mngr

            power line down on McCausland.

&&
Local storm report, Apr 27, 7:54 PM CDT, 36 minutes before
Preliminary Local Storm Report
National Weather Service St Louis MO
754 PM CDT Mon Apr 27 2026

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

0740 PM     Tstm Wnd Gst     1 S Swansea             38.53N 89.99W
04/27/2026  E55 MPH          St. Clair          IL   Public

&&

MCF

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 27, 7:09 PM CDTSevere Thunderstorm WarningLSXBond, Fayette, Macoupin, Madison, Montgomery51 min
Apr 27, 7:12 PM CDTSevere Thunderstorm Warning Considerable damage threatLSXMadison, Monroe, Saint Clair63 min
Apr 27, 7:16 PM CDTFlash Flood WarningLSXMontgomery5 hr
Apr 27, 7:22 PM CDTTornado WarningLSXFayette, Montgomery38 min
Apr 27, 7:24 PM CDTSevere Thunderstorm WarningLSXMonroe51 min
Apr 27, 7:50 PM CDTSevere Thunderstorm WarningLSXBond, Clinton, Fayette, Madison, Marion55 min
Apr 27, 7:52 PM CDTTornado WarningLSXClinton, Saint Clair38 min
Apr 27, 7:54 PM CDTAreal Flood AdvisoryLSXMadison4 hr
Apr 27, 7:56 PM CDTSevere Thunderstorm WarningLSXClinton, Monroe, Randolph, Saint Clair, Washington64 min
Apr 27, 7:59 PM CDTFlash Flood WarningLSXFayette6 hr
Apr 27, 8:15 PM CDTTornado Warning Tornado observedLSXClinton, Fayette, Marion45 min
Apr 27, 8:22 PM CDTAreal Flood AdvisoryLSXBond6 hr
Apr 27, 8:44 PM CDTTornado WarningLSXMarion17 min
Apr 27, 8:55 PM CDTSevere Thunderstorm WarningLSXRandolph30 min
Apr 27, 10:37 PM CDTRiver Flood WarningLSXAdams37 hr
Apr 27, 10:37 PM CDTRiver Flood WarningLSXAdams56 hr
Apr 27, 11:43 PM CDTAreal Flood WarningLSXMacoupin4 hr
Apr 28, 12:16 AM CDTAreal Flood WarningLSXMontgomery6 hr
Apr 28, 1:50 AM CDTAreal Flood WarningLSXFayette6 hr
Apr 28, 7:40 AM CDTAreal Flood WarningLSXFayette12 hr
Apr 28, 11:25 AM CDTRiver Flood WarningLSXBrown25 hr
Apr 28, 11:25 AM CDTRiver Flood WarningLSXMorgan, Pike4 days
Apr 28, 11:38 AM CDTRiver Flood WarningLSXMadison6 days
Apr 28, 11:38 AM CDTRiver Flood WarningLSXMonroe4 days
Apr 28, 11:38 AM CDTRiver Flood WarningLSXMadison5 days
Apr 28, 11:38 AM CDTRiver Flood WarningLSXSaint Clair5 days

Nearby

Severe Thunderstorm Warnings in Illinois, 2026Every severe thunderstorm warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.