Alert archive / Illinois / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 20, NWS St. Louis, MO

March 27, 2021Sainte Genevieve County, Saint Francois County, Missouri; Randolph County, Saint Clair County, Washington County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Mar 27, 2021, 8:11 PM CDT for Sainte Genevieve County, Saint Francois County, Missouri; Randolph County, Saint Clair County, Washington County, Illinois. It was in force for 64 min. 3 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
Mar 27, 2021, 8:11 PM CDT (01:11 UTC)
Expired
Mar 27, 2021, 9:15 PM CDT
In force
64 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Tornado
Possible
Hail
1.0 in
Wind
60.0 mph

Counties Randolph County, IL, Saint Clair County, IL, Washington County, IL, Saint Francois County, MO, Sainte Genevieve County, MO

The radar

The St Louis radar (KLSX), 114 km from the middle of the area, began a volume at 01:15 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
Mar 27, 8:15 PM CDTHAIL 0.752 E Coffman, MOCORRECTS PREVIOUS HAIL REPORT FROM 2 E COFFMAN. REPORT VIA FACEBOOK.
Mar 27, 8:15 PM CDTHAIL 13 Ssw River Aux Vases, MO
Mar 27, 8:57 PM CDTHAIL 0.25Chester, IL

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

The watch it was issued in

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

IssuedProductOfficeLasted
Mar 27, 4:44 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 1.2 hours before the alert went out and 259 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 2021-03-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2021-03-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 square meters per square second.1939587897117136Sfc1 km3 km6 km9 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
933 m above ground
0-6 km bulk shear
86 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
202 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

314 
WUUS53 KLSX 280111
SVRLSX
ILC157-163-189-MOC186-187-280215-
/O.NEW.KLSX.SV.W.0020.210328T0111Z-210328T0215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
811 PM CDT Sat Mar 27 2021

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Southern Washington County in south central Illinois...
  Randolph County in southwestern Illinois...
  Southeastern St. Clair County in southwestern Illinois...
  Ste. Genevieve County in southeastern Missouri...
  Southern St. Francois County in southeastern Missouri...

* Until 915 PM CDT.

* At 811 PM CDT, severe thunderstorms were located along a line
  extending from near Lively Grove to near Knob Lick, moving east 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...
  Farmington, Chester, Ste. Genevieve, Sparta, Nashville, Bremen,
  Steeleville, Marissa, Percy, Coulterville, Tilden, Evansville,
  Lively Grove, Ashley, Baldwin, St. Mary, Knob Lick, Weingarten,
  Womac and Rocky Ridge.

This includes Interstate 55 in Missouri between exits 141 and 150.
 
This also includes Hawn State Park and Felix Valle House State Park.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3822 8959 3795 8960 3780 8968 3785 8979
      3791 8984 3783 8999 3764 9015 3765 9064
      3833 8969 3834 8914 3821 8915
TIME...MOT...LOC 0111Z 262DEG 32KT 3832 8956 3770 9029 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

CVKING
4 follow-up statements
668 
WWUS53 KLSX 280124
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
824 PM CDT Sat Mar 27 2021

MOC187-280133-
/O.CAN.KLSX.SV.W.0020.000000T0000Z-210328T0215Z/
St. Francois MO-
824 PM CDT Sat Mar 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN ST. FRANCOIS COUNTY
IS CANCELLED...

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

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
south central and southwestern Illinois...and southeastern Missouri.

LAT...LON 3822 8959 3795 8960 3780 8968 3785 8979
      3791 8984 3783 8999 3773 9007 3773 9027
      3833 8969 3834 8914 3821 8915
TIME...MOT...LOC 0123Z 262DEG 32KT 3833 8943 3771 9017 

$$

ILC157-163-189-MOC186-280215-
/O.CON.KLSX.SV.W.0020.000000T0000Z-210328T0215Z/
Washington IL-Randolph IL-St. Clair IL-Ste. Genevieve MO-
824 PM CDT Sat Mar 27 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CDT
FOR SOUTHERN WASHINGTON...RANDOLPH...SOUTHEASTERN ST. CLAIR AND
SOUTHEASTERN STE. GENEVIEVE COUNTIES...

At 823 PM CDT, severe thunderstorms were located along a line
extending from near Nashville to near Womac, moving east 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...
Chester, Ste. Genevieve, Sparta, Nashville, Bremen, Steeleville,
Marissa, Percy, Coulterville, Tilden, Evansville, Lively Grove,
Ashley, St. Mary, Coffman, Posen, Eden, Preston, Blair and Ellis
Grove.

This includes Interstate 55 in Missouri between exits 141 and 143.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3822 8959 3795 8960 3780 8968 3785 8979
      3791 8984 3783 8999 3773 9007 3773 9027
      3833 8969 3834 8914 3821 8915
TIME...MOT...LOC 0123Z 262DEG 32KT 3833 8943 3771 9017 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

CVKING
451 
WWUS53 KLSX 280131
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
831 PM CDT Sat Mar 27 2021

ILC163-280141-
/O.CAN.KLSX.SV.W.0020.000000T0000Z-210328T0215Z/
St. Clair IL-
831 PM CDT Sat Mar 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN ST. CLAIR COUNTY
IS CANCELLED...

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

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
south central and southwestern Illinois...and southeastern Missouri.

LAT...LON 3822 8959 3795 8960 3780 8968 3785 8979
      3791 8984 3783 8999 3773 9007 3773 9027
      3822 8969 3833 8946 3834 8914 3821 8915
TIME...MOT...LOC 0131Z 262DEG 32KT 3834 8935 3772 9009 

$$

ILC157-189-MOC186-280215-
/O.CON.KLSX.SV.W.0020.000000T0000Z-210328T0215Z/
Washington IL-Randolph IL-Ste. Genevieve MO-
831 PM CDT Sat Mar 27 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CDT
FOR SOUTHEASTERN WASHINGTON...RANDOLPH AND SOUTHEASTERN STE.
GENEVIEVE COUNTIES...

At 831 PM CDT, severe thunderstorms were located along a line
extending from Nashville to 6 miles northeast of Womac, moving east
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...
Chester, Sparta, Nashville, Bremen, Steeleville, Percy, Coulterville,
Tilden, Ashley, St. Mary, Coffman, Posen, Eden, Blair, Ellis Grove,
Oakdale, Radom, Du Bois, Rockwood and Kaskaskia.

This includes Interstate 55 in Missouri between exits 141 and 143.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3822 8959 3795 8960 3780 8968 3785 8979
      3791 8984 3783 8999 3773 9007 3773 9027
      3822 8969 3833 8946 3834 8914 3821 8915
TIME...MOT...LOC 0131Z 262DEG 32KT 3834 8935 3772 9009 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

CVKING
990 
WWUS53 KLSX 280140
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
840 PM CDT Sat Mar 27 2021

MOC186-280149-
/O.CAN.KLSX.SV.W.0020.000000T0000Z-210328T0215Z/
Ste. Genevieve MO-
840 PM CDT Sat Mar 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN STE. GENEVIEVE
COUNTY IS CANCELLED...

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

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
south central and southwestern Illinois.

LAT...LON 3821 8959 3795 8960 3781 8968 3785 8974
      3785 8979 3788 8980 3791 8984 3787 8992
      3788 8994 3813 8970 3833 8946 3834 8915
      3821 8915
TIME...MOT...LOC 0139Z 262DEG 32KT 3835 8927 3773 9001 

$$

ILC157-189-280215-
/O.CON.KLSX.SV.W.0020.000000T0000Z-210328T0215Z/
Washington IL-Randolph IL-
840 PM CDT Sat Mar 27 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CDT
FOR SOUTHEASTERN WASHINGTON AND SOUTHEASTERN RANDOLPH COUNTIES...

At 839 PM CDT, severe thunderstorms were located along a line
extending from near Ashley to 7 miles west of Perryville, moving east
at 35 mph.

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

SOURCE...Trained spotters reported quarter size hail 13 miles 
         southwest of Ste. Genevieve. 

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

Locations impacted include...
Chester, Sparta, Nashville, Bremen, Steeleville, Percy, Coulterville,
Ashley, Posen, Eden, Blair, Oakdale, Radom, Du Bois, Rockwood, Welge,
Cordes, New Palestine and Shiloh Hill.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3821 8959 3795 8960 3781 8968 3785 8974
      3785 8979 3788 8980 3791 8984 3787 8992
      3788 8994 3813 8970 3833 8946 3834 8915
      3821 8915
TIME...MOT...LOC 0139Z 262DEG 32KT 3835 8927 3773 9001 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

CVKING
702 
WWUS53 KLSX 280149
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
849 PM CDT Sat Mar 27 2021

ILC189-280159-
/O.CAN.KLSX.SV.W.0020.000000T0000Z-210328T0215Z/
Washington IL-
849 PM CDT Sat Mar 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN WASHINGTON COUNTY
IS CANCELLED...

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

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
southwestern Illinois.

LAT...LON 3795 8960 3781 8968 3785 8974 3785 8979
      3788 8980 3791 8984 3787 8992 3788 8994
      3803 8979 3810 8959
TIME...MOT...LOC 0149Z 256DEG 30KT 3801 8967 3778 8988 

$$

ILC157-280215-
/O.CON.KLSX.SV.W.0020.000000T0000Z-210328T0215Z/
Randolph IL-
849 PM CDT Sat Mar 27 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CDT
FOR SOUTHEASTERN RANDOLPH COUNTY...

At 849 PM CDT, severe thunderstorms were located along a line
extending from Steeleville to near Perryville, moving east 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...
Chester, Bremen, Steeleville, Percy, Blair, Rockwood, Welge, New
Palestine and Shiloh Hill.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3795 8960 3781 8968 3785 8974 3785 8979
      3788 8980 3791 8984 3787 8992 3788 8994
      3803 8979 3810 8959
TIME...MOT...LOC 0149Z 256DEG 30KT 3801 8967 3778 8988 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

CVKING

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 27, 7:27 PM CDTSevere Thunderstorm WarningLSXSainte Genevieve, Saint Francois48 min
Mar 27, 7:53 PM CDTSevere Thunderstorm WarningLSXIron, Madison, Reynolds, Saint Francois67 min
Mar 27, 9:10 PM CDTAreal Flood AdvisoryLSXMadison3 hr
Mar 27, 7:03 PM CDTTornado WarningLSXBond, Clinton, Madison, Saint Clair42 min
Mar 27, 7:06 PM CDTSevere Thunderstorm WarningLSXClinton, Monroe, Saint Clair, Washington39 min
Mar 27, 7:13 PM CDTTornado WarningLSXClinton, Saint Clair, Washington47 min
Mar 27, 7:43 PM CDTSevere Thunderstorm WarningLSXBond, Clinton, Fayette, Madison, Marion, Saint Clair and 1 more47 min
Mar 27, 7:45 PM CDTTornado WarningLSXBond, Clinton, Fayette, Marion45 min
Mar 27, 7:59 PM CDTTornado WarningLSXClinton, Marion, Washington31 min
Mar 27, 8:21 PM CDTSevere Thunderstorm WarningLSXClinton, Fayette, Marion, Washington39 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2021Severe Thunderstorm Warnings in Missouri, 2021Every severe thunderstorm warning in 2021

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.