Alert archive / Illinois / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 37, NWS St. Louis, MO

May 3, 2021Montgomery County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at May 3, 2021, 6:45 PM CDT for Montgomery County, Illinois. It was in force for 23 min. 1 report 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, 6:45 PM CDT (23:45 UTC)
Expired
May 3, 2021, 7:08 PM CDT
In force
23 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Montgomery County, IL

The radar

The Lincoln radar (KILX), 90 km from the middle of the area, began a volume at 23:48 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
May 3, 6:55 PM CDTHAIL 1.5Farmersville, 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
May 3, 2:47 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 11.8 hours before the alert went out and 117 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.

707 
WUUS53 KLSX 032345
SVRLSX
ILC135-040030-
/O.NEW.KLSX.SV.W.0037.210503T2345Z-210504T0030Z/

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

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Northwestern Montgomery County in south central Illinois...

* Until 730 PM CDT.

* At 644 PM CDT, a severe thunderstorm was located over Girard,
  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...
  Hillsboro, Raymond, Witt, White Oak, Farmersville, Waggoner, Harvel
  and Honey Bend.

This includes Interstate 55 in Illinois between exits 60 and 63.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3923 8932 3924 8970 3952 8970 3952 8953
      3935 8953 3935 8932
TIME...MOT...LOC 2344Z 275DEG 36KT 3941 8977 

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

Glass
2 follow-up statements
438 
WWUS53 KLSX 032356
SVSLSX

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

ILC135-040030-
/O.CON.KLSX.SV.W.0037.000000T0000Z-210504T0030Z/
Montgomery IL-
656 PM CDT Mon May 3 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM CDT
FOR NORTHWESTERN MONTGOMERY COUNTY...

At 655 PM CDT, a severe thunderstorm was located near Farmersville,
moving east at 40 mph.

HAZARD...60 mph wind gusts and half dollar size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Hillsboro, Raymond, Witt, White Oak, Farmersville, Waggoner, Harvel
and Honey Bend.

This includes Interstate 55 in Illinois between exits 60 and 63.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3923 8932 3924 8970 3952 8970 3952 8953
      3935 8953 3935 8932
TIME...MOT...LOC 2355Z 275DEG 36KT 3940 8962 

HAIL...1.25IN
WIND...60MPH
 
$$

Glass
288 
WWUS53 KLSX 040008
SVSLSX

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

ILC135-040018-
/O.CAN.KLSX.SV.W.0037.000000T0000Z-210504T0030Z/
Montgomery IL-
708 PM CDT Mon May 3 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN MONTGOMERY COUNTY
IS CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.

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

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
St Louis.

LAT...LON 3923 8932 3924 8970 3952 8970 3952 8953
      3935 8953 3935 8932
TIME...MOT...LOC 0005Z 275DEG 36KT 3939 8945 

$$

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, 6:13 PM CDTSevere Thunderstorm WarningLSXGreene, Macoupin47 min
May 3, 6:32 PM CDTSevere Thunderstorm WarningLSXGreene, Macoupin32 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.