Alert archive / Illinois / Tornado Warnings in 2026
Tornado Warning 26, NWS St. Louis, MO
NWS St. Louis, MO issued this tornado warning at Apr 17, 2026, 10:26 PM CDT for Jersey County, Illinois. It was in force for 19 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
- Apr 17, 2026, 10:26 PM CDT (03:26 UTC)
- Expired
- Apr 17, 2026, 10:45 PM CDT
- In force
- 19 min
- Issued by
- NWS St. Louis, MO
- Area
- Storm-based polygon
- Tornado
- Radar indicated
- Hail
- 1.0 in
County Jersey County, IL
The radar
The St Louis radar (KLSX), 45 km from the middle of the area, began a volume at 03:31 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.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Apr 17, 3:31 PM CDT | Tornado Watch | SPC | 8 hr |
The nearest sounding before it
Lincoln, IL (KILX), launched 00:00Z, 3.4 hours before the alert went out and 196 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
- 1309 J/kg
- Mixed-layer CIN
- -103 J/kg
- Mixed-layer LCL
- 1221 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 212 m²/s²
- 0-3 km storm-relative helicity
- 264 m²/s²
- Significant tornado parameter
- 0.8
- Supercell composite
- 8.2
The text
As transmitted.
181
WFUS53 KLSX 180326
TORLSX
ILC083-180345-
/O.NEW.KLSX.TO.W.0026.260418T0326Z-260418T0345Z/
BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service St Louis MO
1026 PM CDT Fri Apr 17 2026
The National Weather Service in St Louis has issued a
* Tornado Warning for...
Southeastern Jersey County in southwestern Illinois...
* Until 1045 PM CDT.
* At 1026 PM CDT, a severe thunderstorm capable of producing a
tornado was located over Grafton, or 9 miles southwest of
Jerseyville, moving east at 50 mph.
HAZARD...Tornado.
SOURCE...Radar indicated rotation.
IMPACT...Flying debris will be dangerous to those caught without
shelter. Mobile homes will be damaged or destroyed. Damage
to roofs, windows and vehicles will occur. Tree damage is
likely.
* This tornado will be near...
Grafton around 1030 PM CDT.
Godfrey around 1035 PM CDT.
Brighton around 1040 PM CDT.
Other locations impacted by the tornado include Otterville, McClusky
and Delhi.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to an interior room on the lowest floor of a well-built building
away from windows. If you are outdoors, in a mobile home, or in a
vehicle, move to the closest substantial shelter and protect yourself
from flying debris.
&&
LAT...LON 3897 9045 3906 9049 3913 9015 3900 9015
3900 9014 3899 9027 3898 9027 3896 9042
3896 9043 3897 9044
TIME...MOT...LOC 0326Z 255DEG 41KT 3900 9042
TORNADO...RADAR INDICATED
MAX HAIL SIZE...<1.00 IN
$$
BRC2 follow-up statements
915
WWUS53 KLSX 180335
SVSLSX
Severe Weather Statement
National Weather Service St Louis MO
1035 PM CDT Fri Apr 17 2026
ILC083-180345-
/O.CON.KLSX.TO.W.0026.000000T0000Z-260418T0345Z/
Jersey IL-
1035 PM CDT Fri Apr 17 2026
...TORNADO WARNING REMAINS IN EFFECT UNTIL 1045 PM CDT FOR
SOUTHEASTERN JERSEY COUNTY...
At 1035 PM CDT, a severe thunderstorm capable of producing a tornado
was located 6 miles northwest of Godfrey, moving east at 50 mph.
HAZARD...Tornado.
SOURCE...Radar indicated rotation.
IMPACT...Flying debris will be dangerous to those caught without
shelter. Mobile homes will be damaged or destroyed. Damage
to roofs, windows and vehicles will occur. Tree damage is
likely.
This tornado will be near...
Godfrey and Brighton around 1040 PM CDT.
Other locations impacted by the tornado include Delhi and McClusky.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to an interior room on the lowest floor of a well-built building
away from windows. If you are outdoors, in a mobile home, or in a
vehicle, move to the closest substantial shelter and protect yourself
from flying debris.
&&
LAT...LON 3900 9040 3906 9038 3913 9015 3900 9015
3900 9027 3898 9027 3896 9040
TIME...MOT...LOC 0326Z 255DEG 42KT 3900 9040
TORNADO...RADAR INDICATED
MAX HAIL SIZE...<1.00 IN
$$
BRC526
WWUS53 KLSX 180345
SVSLSX
Severe Weather Statement
National Weather Service St Louis MO
1045 PM CDT Fri Apr 17 2026
ILC083-180355-
/O.EXP.KLSX.TO.W.0026.000000T0000Z-260418T0345Z/
Jersey IL-
1045 PM CDT Fri Apr 17 2026
...TORNADO WARNING HAS EXPIRED FOR SOUTHEASTERN JERSEY COUNTY...
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been allowed to expire.
A Tornado Watch remains in effect until 1100 PM CDT for a portion of
southwest Illinois.
&&
LAT...LON 3900 9040 3906 9038 3913 9015 3900 9015
3900 9027 3898 9027 3896 9040
TIME...MOT...LOC 0335Z 255DEG 42KT 3903 9028
$$
BRCThe office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 17, 7:21 PM CDT | Severe Thunderstorm Warning | LSX | Adams, Brown, Pike | 54 min |
| Apr 17, 8:12 PM CDT | Severe Thunderstorm Warning | LSX | Brown, Pike | 17 min |
| Apr 17, 9:42 PM CDT | Severe Thunderstorm Warning | LSX | Calhoun | 48 min |
| Apr 17, 9:50 PM CDT | Tornado Warning | LSX | Calhoun | 25 min |
| Apr 17, 10:02 PM CDT | River Flood Warning | LSX | Adams | 12 days |
| Apr 17, 10:14 PM CDT | Severe Thunderstorm Warning | LSX | Jersey, Madison | 31 min |
| Apr 18, 12:05 PM CDT | River Flood Warning | LSX | Adams | 21 days |
| Apr 18, 12:05 PM CDT | River Flood Warning | LSX | Adams | 9 hr |
Nearby
Tornado Warnings in Illinois, 2026Every tornado warning in 2026Tornadoes in 2026
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.