Alert archive / Illinois / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 18, NWS St. Louis, MO

March 27, 20217 counties in Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Mar 27, 2021, 7:43 PM CDT for 7 counties in Illinois. It was in force for 47 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
Mar 27, 2021, 7:43 PM CDT (00:43 UTC)
Expired
Mar 27, 2021, 8:30 PM CDT
In force
47 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Tornado
Possible
Hail
1.0 in
Wind
60.0 mph

Counties Bond County, IL, Clinton County, IL, Fayette County, IL, Madison County, IL, Marion County, IL, Saint Clair County, IL, Washington County, IL

The radar

The St Louis radar (KLSX), 125 km from the middle of the area, began a volume at 00:45 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 CDTTSTM WND DMGCentralia, ILTREE LIMBS DOWN.
Mar 27, 8:29 PM CDTHAIL 0.751 Ne Irvington, ILREPORT FROM MPING: DIME (0.75 IN.).

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, 0.7 hours before the alert went out and 162 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.

431 
WUUS53 KLSX 280043
SVRLSX
ILC005-027-051-119-121-163-189-280130-
/O.NEW.KLSX.SV.W.0018.210328T0043Z-210328T0130Z/

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

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Clinton County in south central Illinois...
  Bond County in south central Illinois...
  Southeastern Madison County in southwestern Illinois...
  Western Marion County in south central Illinois...
  Fayette County in south central Illinois...
  Northern Washington County in south central Illinois...
  Eastern St. Clair County in southwestern Illinois...

* Until 830 PM CDT.

* At 742 PM CDT, severe thunderstorms were located along a line
  extending from Van Burensburg to near Beaver Creek to near Lively
  Grove, moving east at 40 mph.

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

  SOURCE...Public. Numerous trees and powerlines were 
           reported snapped in St. Jacobs and south of Pocahontas.

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

* Locations impacted include...
  Centralia, Highland, Mascoutah, Vandalia, Greenville, Breese,
  Lebanon, Freeburg, New Baden, Carlyle, Nashville, Scott AFB,
  Trenton, New Athens, Aviston, Okawville, St. Elmo, St. Rose,
  Sandoval and Germantown.

This includes the following highways...
 Interstate 70 in Illinois between exits 30 and 76.
 Interstate 64 in Illinois between exits 23 and 61.

This also includes Carlyle Lake Recreational Area.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3847 8914 3834 8915 3832 9000 3899 8954
      3903 8939 3903 8925 3906 8925 3917 8881
      3891 8881
TIME...MOT...LOC 0042Z 258DEG 35KT 3902 8929 3877 8935 3835 8968 

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

BRC
1 follow-up statement
089 
WWUS53 KLSX 280105
SVSLSX

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

ILC119-163-280114-
/O.CAN.KLSX.SV.W.0018.000000T0000Z-210328T0130Z/
Madison IL-St. Clair IL-
805 PM CDT Sat Mar 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MADISON AND
EASTERN ST. CLAIR COUNTIES IN SOUTHWESTERN ILLINOIS 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 Illinois.

LAT...LON 3847 8914 3834 8915 3833 8969 3891 8930
      3899 8927 3903 8925 3906 8925 3917 8881
      3891 8881
TIME...MOT...LOC 0104Z 258DEG 35KT 3906 8903 3881 8909 3839 8942 

$$

ILC005-027-051-121-189-280130-
/O.CON.KLSX.SV.W.0018.000000T0000Z-210328T0130Z/
Clinton IL-Bond IL-Marion IL-Fayette IL-Washington IL-
805 PM CDT Sat Mar 27 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR CLINTON...SOUTHEASTERN BOND...WESTERN MARION...FAYETTE AND
NORTHERN WASHINGTON COUNTIES...

At 804 PM CDT, severe thunderstorms were located along a line
extending from 6 miles northwest of Brownstown to near Shobonier to
near Nashville, moving east at 40 mph.

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

SOURCE...Public. Numerous trees and powerlines were reported snapped 
         in St. Jacobs, IL and south of Pocahontas, IL.

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

Locations impacted include...
Centralia, Vandalia, Breese, Carlyle, Nashville, Okawville, St. Elmo,
Sandoval, Germantown, Wamac, Central City, Odin, Beckemeyer,
Brownstown, Irvington, Mulberry Grove, Patoka, Tamalco, Beaver Creek
and Shobonier.

This also includes Carlyle Lake Recreational Area.
 
This includes the following highways...
 Interstate 70 in Illinois between exits 52 and 76.
 Interstate 64 in Illinois between exits 41 and 61.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3847 8914 3834 8915 3833 8969 3891 8930
      3899 8927 3903 8925 3906 8925 3917 8881
      3891 8881
TIME...MOT...LOC 0104Z 258DEG 35KT 3906 8903 3881 8909 3839 8942 

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

BRC

The office that day

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

IssuedProductOfficeCountiesLasted
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, 7:27 PM CDTSevere Thunderstorm WarningLSXMonroe, Randolph, Saint Clair, Washington48 min
Mar 27, 7:45 PM CDTTornado WarningLSXBond, Clinton, Fayette, Marion45 min
Mar 27, 7:59 PM CDTTornado WarningLSXClinton, Marion, Washington31 min
Mar 27, 8:11 PM CDTSevere Thunderstorm WarningLSXRandolph, Saint Clair, Washington64 min
Mar 27, 8:21 PM CDTSevere Thunderstorm WarningLSXClinton, Fayette, Marion, Washington39 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.