Alert archive / Illinois / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 39, NWS St. Louis, MO

May 3, 2021Bond County, Macoupin County, Montgomery County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at May 3, 2021, 7:39 PM CDT for Bond County, Macoupin County, Montgomery County, Illinois. It was in force for 51 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: May 3, 2021, 7:39 PM CDT (00:39 UTC)
Expired: May 3, 2021, 8:30 PM CDT
In force: 51 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Bond County, IL, Macoupin County, IL, Montgomery County, IL

The radar

The St Louis radar (KLSX), 115 km from the middle of the area, began a volume at 00:42 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

Time	Report	Where	Remark
May 3, 7:42 PM CDT	HAIL 0.75	1 N Gillespie, IL	REPORT FROM MPING: DIME (0.75 IN.).
May 3, 7:43 PM CDT	HAIL 0.5	1 S Gillespie, IL	REPORT FROM MPING: HALF-INCH (0.50 IN.).
May 3, 8:05 PM CDT	HAIL 1	Panama, IL	HAIL ESTIMATED TO BE QUARTER SIZED VIA PHOTOGRAPH. TIME ESTIMATED FROM RADAR.

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.

Issued	Product	Office	Lasted
May 3, 2:47 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 0.7 hours before the alert went out and 142 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 758 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 843 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: -13 m²/s²
0-3 km storm-relative helicity: 74 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 1.4

Open this sounding in Storm Lab

The text

As transmitted.

953 
WUUS53 KLSX 040039
SVRLSX
ILC005-117-135-040130-
/O.NEW.KLSX.SV.W.0039.210504T0039Z-210504T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
739 PM CDT Mon May 3 2021

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Northern Bond County in south central Illinois...
  Southeastern Macoupin County in southwestern Illinois...
  Southern Montgomery County in south central Illinois...

* Until 830 PM CDT.

* At 739 PM CDT, a severe thunderstorm was located over Benld, moving
  east at 40 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...
  Litchfield, Hillsboro, Staunton, Gillespie, Mount Olive, Benld,
  Taylor Springs, Coffeen, Wilsonville, Schram City, Sorento,
  Sawyerville, Mount Clare, East Gillespie, Eagarville, Van
  Burensburg, Panama, Fillmore, White City and Donnellson.

This includes Interstate 55 in Illinois between exits 41 and 52.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3899 8926 3898 8926 3901 8988 3919 8986
      3918 8925 3900 8925
TIME...MOT...LOC 0039Z 274DEG 35KT 3911 8981 

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

Glass

4 follow-up statements

323 
WWUS53 KLSX 040058
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
758 PM CDT Mon May 3 2021

ILC117-040108-
/O.CAN.KLSX.SV.W.0039.000000T0000Z-210504T0130Z/
Macoupin IL-
758 PM CDT Mon May 3 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MACOUPIN COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has 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 3899 8926 3898 8926 3900 8969 3918 8958
      3918 8925 3900 8925
TIME...MOT...LOC 0058Z 278DEG 39KT 3907 8955 

$$

ILC005-135-040130-
/O.CON.KLSX.SV.W.0039.000000T0000Z-210504T0130Z/
Bond IL-Montgomery IL-
758 PM CDT Mon May 3 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR NORTHERN BOND AND SOUTHERN MONTGOMERY COUNTIES...

At 758 PM CDT, a severe thunderstorm was located near Sorento, moving
east at 45 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...
Hillsboro, Taylor Springs, Coffeen, Schram City, Sorento, Van
Burensburg, Panama, Fillmore, Donnellson, Walshville and Chapman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3899 8926 3898 8926 3900 8969 3918 8958
      3918 8925 3900 8925
TIME...MOT...LOC 0058Z 278DEG 39KT 3907 8955 

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

Glass

498 
WWUS53 KLSX 040109
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
809 PM CDT Mon May 3 2021

ILC005-135-040130-
/O.CON.KLSX.SV.W.0039.000000T0000Z-210504T0130Z/
Bond IL-Montgomery IL-
809 PM CDT Mon May 3 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR NORTHEASTERN BOND AND SOUTHEASTERN MONTGOMERY COUNTIES...

At 809 PM CDT, a severe thunderstorm was located near Reno, moving
east 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...
Coffeen, Schram City, Sorento, Van Burensburg, Panama, Fillmore,
Donnellson and Chapman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3899 8926 3898 8926 3900 8959 3918 8944
      3918 8925 3900 8925
TIME...MOT...LOC 0109Z 290DEG 26KT 3902 8950 

HAIL...1.50IN
WIND...60MPH
 
$$

Glass

268 
WWUS53 KLSX 040119
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
819 PM CDT Mon May 3 2021

ILC005-135-040130-
/O.CON.KLSX.SV.W.0039.000000T0000Z-210504T0130Z/
Bond IL-Montgomery IL-
819 PM CDT Mon May 3 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR NORTHEASTERN BOND AND SOUTH CENTRAL MONTGOMERY COUNTIES...

At 819 PM CDT, a severe thunderstorm was located near Woburn, 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...
Coffeen and Van Burensburg. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3899 8926 3898 8926 3899 8947 3909 8942
      3909 8925 3900 8925
TIME...MOT...LOC 0119Z 274DEG 32KT 3901 8939 

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

Glass

082 
WWUS53 KLSX 040130
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
830 PM CDT Mon May 3 2021

ILC005-135-040140-
/O.EXP.KLSX.SV.W.0039.000000T0000Z-210504T0130Z/
Bond IL-Montgomery IL-
830 PM CDT Mon May 3 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN BOND AND SOUTH
CENTRAL MONTGOMERY COUNTIES HAS EXPIRED...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning has
been allowed to expire.  However small hail, gusty winds and heavy
rain are still possible with this thunderstorm.

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

LAT...LON 3899 8926 3898 8926 3899 8947 3909 8942
      3909 8925 3900 8925
TIME...MOT...LOC 0130Z 274DEG 35KT 3900 8926 

$$

Glass

The office that day

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

Issued	Product	Office	Counties	Lasted
May 3, 7:32 PM CDT	Severe Thunderstorm Warning	LSX	Montgomery	21 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2021 Every 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.