Alert archive / Illinois / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 80, NWS Lincoln, IL

April 20, 2023Morgan County, Sangamon County, Illinois

NWS Lincoln, IL issued this severe thunderstorm warning at Apr 20, 2023, 4:38 PM CDT for Morgan County, Sangamon County, Illinois. It was in force for 52 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: Apr 20, 2023, 4:38 PM CDT (21:38 UTC)
Expired: Apr 20, 2023, 5:30 PM CDT
In force: 52 min
Issued by: NWS Lincoln, IL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Morgan County, IL, Sangamon County, IL

The radar

The Lincoln radar (KILX), 65 km from the middle of the area, began a volume at 21:40 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
Apr 20, 5:15 PM CDT	HAIL 1	Sherman, IL

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 37 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

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 20, 1:20 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.6 hours before the alert went out and 114 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1678 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 251 m²/s²
0-3 km storm-relative helicity: 289 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

266 
WUUS53 KILX 202138
SVRILX
ILC137-167-202230-
/O.NEW.KILX.SV.W.0080.230420T2138Z-230420T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Lincoln IL
438 PM CDT Thu Apr 20 2023

The National Weather Service in Lincoln has issued a

* Severe Thunderstorm Warning for...
  Sangamon County in central Illinois...
  Southeastern Morgan County in west central Illinois...

* Until 530 PM CDT.

* At 438 PM CDT, a severe thunderstorm was located Alexander, moving 
  northeast at 50 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* This severe thunderstorm will be near...
  New Berlin around 445 PM CDT.
  Loami around 450 PM CDT.

Other locations in the path of this severe thunderstorm include
Sherman, Riverton and Williamsville.

This includes the following highways...
 Interstate 55 between mile markers 78 and 109.
 Interstate 72 between mile markers 69 and 70, and between mile
markers 72 and 107.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3952 8999 3972 9019 3997 8953 3984 8953
      3953 8954
TIME...MOT...LOC 2138Z 242DEG 45KT 3971 9005 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Shimon

4 follow-up statements

707 
WWUS53 KILX 202204
SVSILX

Severe Weather Statement
National Weather Service Lincoln IL
504 PM CDT Thu Apr 20 2023

ILC137-202213-
/O.CAN.KILX.SV.W.0080.000000T0000Z-230420T2230Z/
Morgan-
504 PM CDT Thu Apr 20 2023

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MORGAN COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 800 PM CDT for
central Illinois.

LAT...LON 3965 8989 3982 8992 3997 8953 3972 8953
TIME...MOT...LOC 2203Z 247DEG 32KT 3980 8977 

$$

ILC167-202230-
/O.CON.KILX.SV.W.0080.000000T0000Z-230420T2230Z/
Sangamon-
504 PM CDT Thu Apr 20 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM CDT
FOR NORTHWESTERN SANGAMON COUNTY...

At 503 PM CDT, a severe thunderstorm was located 2 miles south of 
Farmingdale, moving northeast at 35 mph. 

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
  Rochester, Sherman, Riverton and Williamsville.

This includes the following highways...
 Interstate 55 between mile markers 90 and 109.
 Interstate 72 between mile markers 84 and 107.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3965 8989 3982 8992 3997 8953 3972 8953
TIME...MOT...LOC 2203Z 247DEG 32KT 3980 8977 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Shimon

098 
WWUS53 KILX 202211
SVSILX

Severe Weather Statement
National Weather Service Lincoln IL
511 PM CDT Thu Apr 20 2023

ILC167-202230-
/O.CON.KILX.SV.W.0080.000000T0000Z-230420T2230Z/
Sangamon-
511 PM CDT Thu Apr 20 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM CDT
FOR NORTH CENTRAL SANGAMON COUNTY...

At 511 PM CDT, a severe thunderstorm was located 5 miles southwest 
of Sherman, moving northeast at 45 mph. 

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Springfield, Sherman, Riverton, Williamsville, Grandview, Spaulding,
Clear Lake and Capital Airport.

This includes the following highways...
 Interstate 55 between mile markers 98 and 109.
 Interstate 72 between mile markers 106 and 107.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3977 8978 3988 8977 3997 8953 3982 8953
TIME...MOT...LOC 2211Z 238DEG 40KT 3985 8970 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

Shimon

406 
WWUS53 KILX 202220
SVSILX

Severe Weather Statement
National Weather Service Lincoln IL
520 PM CDT Thu Apr 20 2023

ILC167-202230-
/O.CON.KILX.SV.W.0080.000000T0000Z-230420T2230Z/
Sangamon-
520 PM CDT Thu Apr 20 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM CDT
FOR NORTH CENTRAL SANGAMON COUNTY...

At 519 PM CDT, a severe thunderstorm was located over Sherman, 
moving northeast at 45 mph. 

HAZARD...Quarter size hail.

SOURCE...Trained weather spotters.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Springfield, Sherman, Riverton, Williamsville, Grandview, Spaulding,
Clear Lake and Capital Airport.

This includes the following highways...
 Interstate 55 between mile markers 98 and 109.
 Interstate 72 between mile markers 106 and 107.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3978 8975 3989 8974 3997 8953 3982 8953
TIME...MOT...LOC 2219Z 238DEG 40KT 3990 8960 

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

Shimon

420 
WWUS53 KILX 202227
SVSILX

Severe Weather Statement
National Weather Service Lincoln IL
527 PM CDT Thu Apr 20 2023

ILC167-202236-
/O.EXP.KILX.SV.W.0080.000000T0000Z-230420T2230Z/
Sangamon-
527 PM CDT Thu Apr 20 2023

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL SANGAMON COUNTY
WILL EXPIRE AT 530 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However small hail
is still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 800 PM CDT for
central Illinois.

LAT...LON 3978 8975 3989 8974 3997 8953 3982 8953
TIME...MOT...LOC 2226Z 242DEG 45KT 3994 8951 

$$

Shimon

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Lincoln, IL wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 20, 3:52 PM CDT, 46 minutes earlier.

Area forecast discussion, Apr 20, 3:52 PM CDT, 46 minutes before

Area Forecast Discussion
National Weather Service Lincoln IL
352 PM CDT Thu Apr 20 2023

.SYNOPSIS...
Issued at 351 PM CDT Thu Apr 20 2023

Line of severe storms has developed just ahead of a cold front and
will move across the central Illinois this evening, with the
threat of large hail, damaging winds, and possible tornadoes;
mainly west of I-57. Storms should diminish as they get east of
I-55. A secondary cold front then swings through Friday night,
bringing much colder temperatures and the potential for
widespread frost over the weekend. Dry and seasonable weather is
anticipated into the middle of next week.

&&

.SHORT TERM...(This evening through Friday)
ISSUED AT 351 PM CDT Thu Apr 20 2023

Severe storms have developed ahead of the cold front that is
forecast to move into and through the CWA this evening.
Instability and shear supports strong storms with potential of
large hail and damaging winds. Tornadoes are also possible with
some of the cells across the northern parts of the CWA. These
storms will move northeast as the line moves east. As the storms
get further east, instability and shear diminishes, so storms
should also diminish in intensity. Strong winds out ahead of these
storms will also continue with gusts around 45 mph still common in
the wind advisory area and will be allowed to expire at 5 pm. As
the front moves to the east, showers and isolated storms will
linger in the east and southeast, mainly east of I-57. Cooler
temps will also move into the region. Overnight lows will be in
the 50s...however highs tomorrow will only get into the 60s.

&&

.LONG TERM...(Friday night through Thursday)
ISSUED AT 351 PM CDT Thu Apr 20 2023

Showers will continue to linger in the east and southeast Friday
night. However, dry weather is expected through the weekend and
the first part of next week. Overnight lows will drop into the
middle 30s for Sat night, but into the lower to around 30 for
Sunday night. Widespread frost will be possible Sun night/Mon
morning. Unsettled weather returns to the area for Tuesday
through Thursday with chances of showers through the period.
Cooler than normal temps are expected as well, with temps only
reaching into the 60s and lows in the 40s.

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1247 PM CDT Thu Apr 20 2023

VFR conditions will prevail at all sites next 24hrs...even with
storms expected later this afternoon into this evening. Broken
cigs around 5kft will be common across all sites this afternoon,
but then when storms are on-site, cigs around 3.5kft can be
expected...with vis around 4sm as well. Conditions will likely be
less during the t-storms, but brief. Have given each site a 2hr
window when storms could be on station and also a VCTS to cover an
hr after the TEMPO group. Once storms pass, showers will continue
for an hour or two, followed by VCSH for the rest of the evening.
Cigs will rise into the mid levels around 10kft for the evening
and then broken cirrus expected during the overnight hours. This
high cirrus will likely continue into the morning hours tomorrow.
Winds will be southwest during the day for all sites, ahead of the
front. Then behind the front become westerly and then
northwesterly later tonight. Winds will be quite gusty, with gusts
of up to 35kts, today but then taper after the line of storms
and into this evening.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 5 PM CDT this afternoon for Ilz038-042>046-
051>057-061-062-066.

&&

SYNOPSIS...Auten
SHORT TERM...Auten
LONG TERM...Auten
AVIATION...Auten

Hazardous weather outlook, Apr 20, 4:06 PM CDT, 32 minutes before

Hazardous Weather Outlook
National Weather Service Lincoln IL
406 PM CDT Thu Apr 20 2023

ILZ027>031-036>038-040>044-047>054-061-066-211200-
Knox-Stark-Peoria-Marshall-Woodford-Fulton-Tazewell-McLean-Schuyler-
Mason-Logan-De Witt-Piatt-Cass-Menard-Scott-Morgan-Sangamon-
Christian-Macon-Moultrie-Shelby-Effingham-
406 PM CDT Thu Apr 20 2023

This Hazardous Weather Outlook is for central Illinois, east
central Illinois, southeast Illinois and west central Illinois.

.DAY ONE...Tonight.

Southwest winds will gust to around 30-35 mph this evening and then
diminish after 5 pm. This could cause difficult travel for high
profile vehicles.

Thunderstorms are likely this evening. Some of the storms could be
severe, with damaging wind gusts and large hail the primary hazards.
A tornado or two cannot be ruled out.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Low temperatures will drop near freezing Sunday morning and Monday
morning. This could damage sensitive unprotected outdoor vegetation.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed this evening through 7-8
pm.

ILZ045-046-055>057-062-063-067-068-071>073-211200-
Champaign-Vermilion-Douglas-Coles-Edgar-Cumberland-Clark-Jasper-
Crawford-Clay-Richland-Lawrence-
406 PM CDT Thu Apr 20 2023

This Hazardous Weather Outlook is for east central Illinois and
southeast Illinois.

.DAY ONE...Tonight.

Southwest winds will gust 35-45 mph this evening but diminish after 5
pm. This could cause difficult travel for high profile vehicles. The
gusty winds will also allow outdoor fire to spread quickly, so
burning is discouraged.

Thunderstorms are likely this evening. Some of the storms could be
severe, with damaging wind gusts and hail the primary threats.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Scattered thunderstorms are forecast on Friday. Severe weather is
not expected.

Low temperatures will drop near freezing Sunday morning and Monday
morning. This could damage sensitive unprotected outdoor vegetation.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed this evening after 8 pm.

Auten

In the hours before

Local storm report, Apr 20, 3:48 PM CDT, 50 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LINCOLN IL
348 PM CDT THU APR 20 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0344 PM     HAIL             3 NNE LITTLETON         40.27N 90.60W
04/20/2023  M0.75 INCH       SCHUYLER           IL   PUBLIC

            REPORT FROM MPING: DIME (0.75 IN.).

&&

07

Local storm report, Apr 20, 4:00 PM CDT, 38 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LINCOLN IL
400 PM CDT THU APR 20 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0358 PM     HAIL             ALTONA                  41.12N 90.16W
04/20/2023  M0.50 INCH       KNOX               IL   CO-OP OBSERVER

            LOTS OF MARBLE SIZE HAIL FALLING AT ALTONA
            STATION ELEVATION: 758 FT.

&&

07

Local storm report, Apr 20, 4:01 PM CDT, 37 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LINCOLN IL
401 PM CDT THU APR 20 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0355 PM     HAIL             CUBA                    40.49N 90.19W
04/20/2023  M1.00 INCH       FULTON             IL   EMERGENCY MNGR

            QUARTER SIZE HAIL IN CUBA.

&&

Local storm report, Apr 20, 4:02 PM CDT, 36 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LINCOLN IL
402 PM CDT THU APR 20 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0358 PM     HAIL             3 S CUBA                40.45N 90.19W
04/20/2023  M1.25 INCH       FULTON             IL   PUBLIC

            REPORT FROM MPING: HALF DOLLAR (1.25 IN.).

&&

07

Local storm report, Apr 20, 4:16 PM CDT, 22 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LINCOLN IL
416 PM CDT THU APR 20 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0414 PM     HAIL             CANTON                  40.56N 90.04W
04/20/2023  E0.70 INCH       FULTON             IL   PUBLIC

            FROM SOCIAL MEDIA.

&&

37

Local storm report, Apr 20, 4:18 PM CDT, 20 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LINCOLN IL
418 PM CDT THU APR 20 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0410 PM     HAIL             CANTON                  40.56N 90.04W
04/20/2023  E1.00 INCH       FULTON             IL   EMERGENCY MNGR

&&

37

The office that day

Everything else NWS Lincoln, IL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 20, 1:49 AM CDT	Wind Advisory	ILX	Champaign, Christian, Coles, Cumberland, DeWitt, Douglas and 10 more	15 hr
Apr 20, 2:19 PM CDT	Severe Thunderstorm Warning	ILX	Schuyler	26 min
Apr 20, 2:43 PM CDT	Severe Thunderstorm Warning	ILX	Schuyler	32 min
Apr 20, 3:16 PM CDT	Severe Thunderstorm Warning	ILX	Fulton, Schuyler	29 min
Apr 20, 3:23 PM CDT	Severe Thunderstorm Warning	ILX	Morgan, Scott	37 min
Apr 20, 3:31 PM CDT	Severe Thunderstorm Warning	ILX	Knox	29 min
Apr 20, 3:34 PM CDT	Tornado Warning	ILX	Fulton	26 min
Apr 20, 3:56 PM CDT	Severe Thunderstorm Warning	ILX	Knox, Stark	38 min
Apr 20, 3:59 PM CDT	Severe Thunderstorm Warning	ILX	Fulton, Peoria, Tazewell	31 min
Apr 20, 4:00 PM CDT	Severe Thunderstorm Warning	ILX	Morgan, Scott	60 min
Apr 20, 4:28 PM CDT	Severe Thunderstorm Warning	ILX	Fulton, Mason, Peoria, Tazewell, Woodford	32 min
Apr 20, 4:49 PM CDT	Tornado Warning	ILX	Peoria, Tazewell, Woodford	26 min
Apr 20, 4:55 PM CDT	Severe Thunderstorm Warning Considerable damage threat	ILX	Fulton, Marshall, Peoria, Tazewell, Woodford	51 min
Apr 20, 4:56 PM CDT	Flash Flood Warning	ILX	Fulton, Peoria, Tazewell, Woodford	2 hr
Apr 20, 5:06 PM CDT	Severe Thunderstorm Warning	ILX	Fulton, Mason, Schuyler	41 min
Apr 20, 5:52 PM CDT	Special Weather Statement	ILX	Christian	23 min
Apr 20, 6:09 PM CDT	Special Weather Statement	ILX	McLean	36 min
Apr 20, 6:24 PM CDT	Special Weather Statement	ILX	Christian, Moultrie	36 min
Apr 20, 6:35 PM CDT	Severe Thunderstorm Warning	ILX	Christian, Macon, Moultrie, Piatt, Shelby	40 min
Apr 20, 6:53 PM CDT	Special Weather Statement	ILX	Champaign	37 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2023 Every severe thunderstorm warning in 2023

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.