Alert archive / Illinois / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 136, NWS St. Louis, MO
NWS St. Louis, MO issued this severe thunderstorm warning at Jul 29, 2021, 9:56 PM CDT for 4 counties in Illinois. It was in force for 34 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
- Jul 29, 2021, 9:56 PM CDT (02:56 UTC)
- Expired
- Jul 29, 2021, 10:30 PM CDT
- In force
- 34 min
- Issued by
- NWS St. Louis, MO
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Bond County, IL, Macoupin County, IL, Madison County, IL, Montgomery County, IL
The radar
The St Louis radar (KLSX), 102 km from the middle of the area, began a volume at 02:58 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 nearest sounding before it
Lincoln, IL (KILX), launched 00:00Z, 2.9 hours before the alert went out and 145 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.
- Mixed-layer CAPE
- 1257 J/kg
- Mixed-layer CIN
- -140 J/kg
- Mixed-layer LCL
- 1185 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- -4 m²/s²
- 0-3 km storm-relative helicity
- 88 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 4.1
The text
As transmitted.
248 WUUS53 KLSX 300256 SVRLSX ILC005-117-119-135-300330- /O.NEW.KLSX.SV.W.0136.210730T0256Z-210730T0330Z/ BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service St Louis MO 956 PM CDT Thu Jul 29 2021 The National Weather Service in St Louis has issued a * Severe Thunderstorm Warning for... Northwestern Bond County in south central Illinois... Northeastern Madison County in southwestern Illinois... Southeastern Macoupin County in southwestern Illinois... Southwestern Montgomery County in south central Illinois... * Until 1030 PM CDT. * At 955 PM CDT, severe thunderstorms were located along a line extending from near Carlinville to near Alhambra, moving east at 40 mph. HAZARD...60 mph wind gusts. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. * Severe thunderstorms will be near... Sorento around 1000 PM CDT. Reno around 1005 PM CDT. Litchfield around 1015 PM CDT. Other locations in the path of these severe thunderstorms include Greenville, Hillsboro, Taylor Springs, Coffeen and Schram City. This includes Interstate 55 in Illinois between exits 33 and 52. This also includes Beaver Dam State Park and Lake Lou Yaeger. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 3927 8939 3886 8939 3890 9000 3926 9000 TIME...MOT...LOC 0255Z 281DEG 33KT 3922 8982 3891 8965 HAIL...<.75IN WIND...60MPH $$ 19
2 follow-up statements
647 WWUS53 KLSX 300314 SVSLSX Severe Weather Statement National Weather Service St Louis MO 1014 PM CDT Thu Jul 29 2021 ILC005-117-119-135-300330- /O.CON.KLSX.SV.W.0136.000000T0000Z-210730T0330Z/ Bond IL-Madison IL-Macoupin IL-Montgomery IL- 1014 PM CDT Thu Jul 29 2021 ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1030 PM CDT FOR NORTHWESTERN BOND COUNTY IN SOUTH CENTRAL ILLINOIS...NORTHEASTERN MADISON...SOUTHEASTERN MACOUPIN COUNTIES IN SOUTHWESTERN ILLINOIS AND SOUTHWESTERN MONTGOMERY COUNTIES IN SOUTH CENTRAL ILLINOIS... At 1013 PM CDT, severe thunderstorms were located along a line extending from Litchfield to near Greenville, moving east at 40 mph. HAZARD...60 mph wind gusts. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. Locations impacted include... Greenville, Schram City and Coffeen. This includes Interstate 55 in Illinois between exits 30 and 44. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 3917 8939 3886 8939 3889 8990 3917 8988 TIME...MOT...LOC 0313Z 281DEG 33KT 3919 8965 3888 8948 HAIL...<.75IN WIND...60MPH $$ 19
463
WWUS53 KLSX 300326
SVSLSX
Severe Weather Statement
National Weather Service St Louis MO
1026 PM CDT Thu Jul 29 2021
ILC005-117-119-135-300336-
/O.EXP.KLSX.SV.W.0136.000000T0000Z-210730T0330Z/
Bond IL-Madison IL-Macoupin IL-Montgomery IL-
1026 PM CDT Thu Jul 29 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN BOND COUNTY IN
SOUTH CENTRAL ILLINOIS...NORTHEASTERN MADISON...SOUTHEASTERN MACOUPIN
COUNTIES IN SOUTHWESTERN ILLINOIS AND SOUTHWESTERN MONTGOMERY
COUNTIES IN SOUTH CENTRAL ILLINOIS WILL EXPIRE AT 1030 PM CDT...
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However gusty
winds are still possible with these thunderstorms.
LAT...LON 3917 8939 3886 8939 3889 8990 3917 8988
TIME...MOT...LOC 0326Z 281DEG 33KT 3917 8953 3886 8936
$$
19The office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 29, 10:54 PM CDT | Areal Flood Advisory | LSX | Calhoun, Greene, Jersey | 3 hr |
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.