Alert archive / Illinois / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 35, NWS St. Louis, MO

May 3, 2021Greene County, Macoupin County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at May 3, 2021, 6:13 PM CDT for Greene County, Macoupin County, Illinois. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 3, 2021, 6:13 PM CDT (23:13 UTC)
Expired
May 3, 2021, 7:00 PM CDT
In force
47 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Greene County, IL, Macoupin County, IL

The radar

The Lincoln radar (KILX), 94 km from the middle of the area, began a volume at 23:13 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.

The watch it was issued in

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

IssuedProductOfficeLasted
May 3, 2:47 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 11.2 hours before the alert went out and 136 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 12:00Z on 2021-05-03Temperature 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 12:00Z on 2021-05-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 square meters per square second.1939Sfc1 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
460 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
56 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

632 
WUUS53 KLSX 032313
SVRLSX
ILC061-117-040000-
/O.NEW.KLSX.SV.W.0035.210503T2313Z-210504T0000Z/

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

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Northeastern Greene County in southwestern Illinois...
  Northern Macoupin County in southwestern Illinois...

* Until 700 PM CDT.

* At 613 PM CDT, a severe thunderstorm was located over Athensville,
  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...
  Virden, Girard, Palmyra, Athensville, Nilwood, Modesto, Standard
  City, Scottville and Atwater.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3935 8970 3935 8971 3933 8970 3938 9025
      3952 9021 3952 8970
TIME...MOT...LOC 2313Z 269DEG 32KT 3947 9015 

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

Glass
2 follow-up statements
524 
WWUS53 KLSX 032322
SVSLSX

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

ILC061-032331-
/O.CAN.KLSX.SV.W.0035.000000T0000Z-210504T0000Z/
Greene IL-
622 PM CDT Mon May 3 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN GREENE 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 3935 8970 3935 8971 3933 8970 3937 9015
      3952 9015 3952 8970
TIME...MOT...LOC 2321Z 269DEG 32KT 3947 9005 

$$

ILC117-040000-
/O.CON.KLSX.SV.W.0035.000000T0000Z-210504T0000Z/
Macoupin IL-
622 PM CDT Mon May 3 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM CDT
FOR NORTHERN MACOUPIN COUNTY...

At 621 PM CDT, a severe thunderstorm was located near Palmyra, 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...
Virden, Girard, Palmyra, Nilwood, Modesto, Standard City, Scottville
and Atwater.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3935 8970 3935 8971 3933 8970 3937 9015
      3952 9015 3952 8970
TIME...MOT...LOC 2321Z 269DEG 32KT 3947 9005 

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

Glass
789 
WWUS53 KLSX 032333
SVSLSX

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

ILC117-040000-
/O.CON.KLSX.SV.W.0035.000000T0000Z-210504T0000Z/
Macoupin IL-
633 PM CDT Mon May 3 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM CDT
FOR NORTHEASTERN MACOUPIN COUNTY...

At 633 PM CDT, a severe thunderstorm was located near Palmyra, 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...
Virden, Girard, Nilwood, Modesto and Standard City. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3935 8970 3935 8971 3933 8970 3938 8998
      3952 8998 3952 8970
TIME...MOT...LOC 2333Z 269DEG 32KT 3947 8991 

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

Glass

The office that day

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

IssuedProductOfficeCountiesLasted
May 3, 2:54 PM CDTSevere Thunderstorm WarningLSXAdams51 min
May 3, 3:27 PM CDTSevere Thunderstorm WarningLSXAdams, Brown48 min
May 3, 4:13 PM CDTSevere Thunderstorm WarningLSXBrown28 min
May 3, 6:32 PM CDTSevere Thunderstorm WarningLSXGreene, Macoupin32 min
May 3, 6:45 PM CDTSevere Thunderstorm WarningLSXMontgomery23 min

Nearby

Severe Thunderstorm Warnings in Illinois, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.