Alert archive / Illinois / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 48, NWS St. Louis, MO
NWS St. Louis, MO issued this severe thunderstorm warning at May 27, 2021, 11:32 AM CDT for Greene County, Macoupin County, Illinois. It was in force for 43 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 27, 2021, 11:32 AM CDT (16:32 UTC)
- Expired
- May 27, 2021, 12:15 PM CDT
- In force
- 43 min
- Issued by
- NWS St. Louis, MO
- Area
- Storm-based polygon
- Tornado
- Possible
- Hail
- 0.88 in
- Wind
- 70.0 mph
Counties Greene County, IL, Macoupin County, IL
The radar
The Lincoln radar (KILX), 99 km from the middle of the area, began a volume at 16:33 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 27, 11:39 AM CDT | TSTM WND GST 42 | Roodhouse, 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.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| May 27, 11:26 AM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
The nearest sounding before it
Lincoln, IL (KILX), launched 12:00Z, 4.5 hours before the alert went out and 147 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1679 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 130 m²/s²
- 0-3 km storm-relative helicity
- 150 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
169
WUUS53 KLSX 271632
SVRLSX
ILC061-117-271715-
/O.NEW.KLSX.SV.W.0048.210527T1632Z-210527T1715Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
1132 AM CDT Thu May 27 2021
The National Weather Service in St Louis has issued a
* Severe Thunderstorm Warning for...
Greene County in southwestern Illinois...
Northern Macoupin County in southwestern Illinois...
* Until 1215 PM CDT.
* At 1132 AM CDT, severe thunderstorms were located along a line
extending from near Alsey to 6 miles southwest of Carrollton,
moving east at 40 mph.
HAZARD...70 mph wind gusts and nickel size hail.
SOURCE...Radar indicated.
IMPACT...Expect considerable tree damage. Damage is likely to
mobile homes, roofs, and outbuildings.
* Severe thunderstorms will be near...
White Hall and Roodhouse around 1135 AM CDT.
Carrollton around 1140 AM CDT.
Other locations in the path of these severe thunderstorms include
Greenfield and Palmyra.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3948 8970 3925 9061 3952 9058 3952 8970
TIME...MOT...LOC 1632Z 250DEG 35KT 3955 9048 3924 9050
TORNADO...POSSIBLE
HAIL...0.88IN
WIND...70MPH
$$
MRM2 follow-up statements
999
WWUS53 KLSX 271641
SVSLSX
Severe Weather Statement
National Weather Service St Louis MO
1141 AM CDT Thu May 27 2021
ILC061-117-271715-
/O.CON.KLSX.SV.W.0048.000000T0000Z-210527T1715Z/
Greene IL-Macoupin IL-
1141 AM CDT Thu May 27 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1215 PM CDT
FOR NORTHERN GREENE AND NORTHERN MACOUPIN COUNTIES...
At 1141 AM CDT, severe thunderstorms were located along a line
extending from near Alsey to near Carrollton, moving east at 40 mph.
HAZARD...70 mph wind gusts and nickel size hail.
SOURCE...Radar indicated.
IMPACT...Expect considerable tree damage. Damage is likely to mobile
homes, roofs, and outbuildings.
Locations impacted include...
Greenfield, Palmyra and Virden.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3948 8970 3928 9051 3952 9054 3952 8970
TIME...MOT...LOC 1641Z 250DEG 36KT 3960 9039 3928 9036
TORNADO...POSSIBLE
HAIL...0.88IN
WIND...70MPH
$$
MRM614
WWUS53 KLSX 271654
SVSLSX
Severe Weather Statement
National Weather Service St Louis MO
1154 AM CDT Thu May 27 2021
ILC061-117-271715-
/O.CON.KLSX.SV.W.0048.000000T0000Z-210527T1715Z/
Greene IL-Macoupin IL-
1154 AM CDT Thu May 27 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1215 PM CDT
FOR NORTHEASTERN GREENE AND NORTHERN MACOUPIN COUNTIES...
At 1154 AM CDT, severe thunderstorms were located along a line
extending from Woodson to near Greenfield, moving east at 40 mph.
HAZARD...70 mph wind gusts and nickel size hail.
SOURCE...Radar indicated.
IMPACT...Expect considerable tree damage. Damage is likely to mobile
homes, roofs, and outbuildings.
Locations impacted include...
Virden, White Hall, Roodhouse, Palmyra, Athensville, Wrights, Modesto
and Scottville.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3932 9036 3952 9039 3952 8970 3948 8970
TIME...MOT...LOC 1654Z 254DEG 35KT 3964 9020 3932 9017
TORNADO...POSSIBLE
HAIL...0.88IN
WIND...70MPH
$$
MRMThe office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 27, 11:13 AM CDT | Severe Thunderstorm Warning | LSX | Calhoun, Greene, Jersey | 47 min |
| May 27, 11:50 AM CDT | Severe Thunderstorm Warning | LSX | Calhoun, Greene, Jersey, Macoupin, Madison, Saint Clair | 55 min |
| May 27, 12:07 PM CDT | Severe Thunderstorm Warning | LSX | Greene, Macoupin, Montgomery | 38 min |
| May 27, 12:26 PM CDT | Tornado Warning | LSX | Macoupin, Madison | 34 min |
| May 27, 12:39 PM CDT | Areal Flood Advisory | LSX | Calhoun, Madison | 3 hr |
| May 27, 12:56 PM CDT | Tornado Warning | LSX | Bond, Macoupin, Madison, Montgomery | 28 min |
| May 27, 2:16 PM CDT | Areal Flood Advisory | LSX | Bond, Fayette | 3 hr |
| May 27, 2:31 PM CDT | Severe Thunderstorm Warning | LSX | Clinton, Fayette, Marion | 44 min |
| May 27, 2:46 PM CDT | Severe Thunderstorm Warning | LSX | Monroe, Randolph | 29 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.