Alert archive / Illinois / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 4, NWS Quad Cities, IA

June 18, 2021Henderson County, Mercer County, Warren County, Illinois

NWS Quad Cities, IA issued this severe thunderstorm warning at Jun 18, 2021, 10:45 PM CDT for Henderson County, Mercer County, Warren County, Illinois. It was in force for 48 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: Jun 18, 2021, 10:45 PM CDT (03:45 UTC)
Expired: Jun 18, 2021, 11:33 PM CDT
In force: 48 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 1.75 in
Wind: 50.0 mph

Counties Henderson County, IL, Mercer County, IL, Warren County, IL

The radar

The Quad Cities radar (KDVN), 61 km from the middle of the area, began a volume at 03:48 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

Time	Report	Where	Remark
Jun 18, 11:04 PM CDT	TSTM WND DMG	2 Ne Shanghai City, IL	LARGE TREE DOWN. PICTURE POSTED TO SOCIAL MEDIA.

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
Jun 18, 10:08 PM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 3.8 hours before the alert went out and 64 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: 4 J/kg
Mixed-layer CIN: -335 J/kg
Mixed-layer LCL: 2572 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: -15 m²/s²
0-3 km storm-relative helicity: 55 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

995 
WUUS53 KDVN 190345
SVRDVN
ILC071-131-187-190445-
/O.NEW.KDVN.SV.W.0004.210619T0345Z-210619T0445Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
1045 PM CDT Fri Jun 18 2021

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Northeastern Henderson County in west central Illinois...
  Northern Warren County in west central Illinois...
  Mercer County in northwestern Illinois...

* Until 1145 PM CDT.

* At 1044 PM CDT, a severe thunderstorm was located over Seaton, or 7
  miles southwest of Aledo, moving east at 25 mph.

  HAZARD...Golf ball size hail.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect 
           damage to roofs, siding, windows, and vehicles.

* This severe thunderstorm will be near...
  Aledo and Little York around 1100 PM CDT.

Other locations in the path of this severe thunderstorm include
Burgess, Lake Warren and North Henderson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4103 9094 4107 9095 4121 9094 4122 9044
      4095 9044
TIME...MOT...LOC 0344Z 271DEG 10KT 4110 9080 

HAIL...1.75IN
WIND...<50MPH
 
$$

Ervin

6 follow-up statements

291 
WWUS53 KDVN 190352
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1052 PM CDT Fri Jun 18 2021

ILC071-131-187-190445-
/O.CON.KDVN.SV.W.0004.000000T0000Z-210619T0445Z/
Henderson IL-Warren IL-Mercer IL-
1052 PM CDT Fri Jun 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1145 PM CDT
FOR NORTHEASTERN HENDERSON...NORTHERN WARREN AND SOUTHEASTERN MERCER
COUNTIES...

At 1051 PM CDT, a severe thunderstorm was located over Seaton, or
near Aledo, moving east at 20 mph.

HAZARD...Golf ball size hail.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect damage 
         to roofs, siding, windows, and vehicles.

This severe storm will be near...
  Aledo and Little York around 1100 PM CDT.

Other locations in the path of this severe thunderstorm include Lake
Warren, Burgess, Viola and North Henderson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
the Quad Cities.

&&

LAT...LON 4103 9094 4107 9095 4121 9094 4122 9044
      4095 9044
TIME...MOT...LOC 0351Z 271DEG 10KT 4110 9077 

HAIL...1.75IN
WIND...<50MPH
 
$$

Ervin

534 
WWUS53 KDVN 190356
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1056 PM CDT Fri Jun 18 2021

ILC071-131-187-190445-
/O.CON.KDVN.SV.W.0004.000000T0000Z-210619T0445Z/
Henderson IL-Warren IL-Mercer IL-
1056 PM CDT Fri Jun 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1145 PM CDT
FOR NORTHEASTERN HENDERSON...NORTHERN WARREN AND SOUTHEASTERN MERCER
COUNTIES...

At 1056 PM CDT, a severe thunderstorm was located over Seaton, or
near Aledo, moving east at 20 mph.

HAZARD...Ping pong ball size hail.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect damage 
         to roofs, siding, windows, and vehicles.

Locations impacted include...
  Lake Warren and Burgess.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
the Quad Cities.

&&

LAT...LON 4103 9094 4107 9095 4121 9094 4122 9044
      4095 9044
TIME...MOT...LOC 0356Z 271DEG 10KT 4110 9075 

HAIL...1.50IN
WIND...<50MPH
 
$$

Ervin

613 
WWUS53 KDVN 190400
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1100 PM CDT Fri Jun 18 2021

ILC071-131-187-190445-
/O.CON.KDVN.SV.W.0004.000000T0000Z-210619T0445Z/
Henderson IL-Warren IL-Mercer IL-
1100 PM CDT Fri Jun 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1145 PM CDT
FOR NORTHEASTERN HENDERSON...NORTHERN WARREN AND SOUTHEASTERN MERCER
COUNTIES...

At 1100 PM CDT, a severe thunderstorm was located near Burgess, or 10
miles southeast of Aledo, moving east at 25 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

This severe storm will be near...
  Lake Warren around 1105 PM CDT.

Other locations in the path of this severe thunderstorm include North
Henderson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
the Quad Cities.

&&

LAT...LON 4103 9094 4107 9095 4121 9073 4122 9044
      4095 9044
TIME...MOT...LOC 0400Z 280DEG 20KT 4107 9065 

HAIL...1.50IN
WIND...60MPH
 
$$

Ervin

024 
WWUS53 KDVN 190409 RRA
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1109 PM CDT Fri Jun 18 2021

ILC071-131-187-190445-
/O.CON.KDVN.SV.W.0004.000000T0000Z-210619T0445Z/
Henderson IL-Warren IL-Mercer IL-
1109 PM CDT Fri Jun 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1145 PM CDT
FOR NORTHEASTERN HENDERSON...NORTHERN WARREN AND SOUTHEASTERN MERCER
COUNTIES...

At 1109 PM CDT, a severe thunderstorm was located near North
Henderson, or 10 miles northeast of Monmouth, moving east at 15 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

This severe storm will be near...
  Lake Warren around 1115 PM CDT.

Other locations in the path of this severe thunderstorm include North
Henderson.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
the Quad Cities.

&&

LAT...LON 4103 9094 4107 9095 4121 9061 4122 9044
      4095 9044
TIME...MOT...LOC 0409Z 276DEG 12KT 4105 9055 

HAIL...1.00IN
WIND...70MPH
 
$$

Ervin

021 
WWUS53 KDVN 190418 RRA
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1118 PM CDT Fri Jun 18 2021

ILC071-131-187-190445-
/O.CON.KDVN.SV.W.0004.000000T0000Z-210619T0445Z/
Henderson IL-Warren IL-Mercer IL-
1118 PM CDT Fri Jun 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1145 PM CDT
FOR NORTHEASTERN HENDERSON...NORTHERN WARREN AND SOUTHEASTERN MERCER
COUNTIES...

At 1118 PM CDT, a severe thunderstorm was located near North
Henderson, or near Galesburg, moving east at 15 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

This severe thunderstorm will remain over mainly rural areas of
northeastern Henderson, northern Warren and southeastern Mercer
Counties, including the following locations... Bald Bluff, Gerlaw,
Big River State Forest and Alexis.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
the Quad Cities.

&&

LAT...LON 4103 9094 4107 9095 4108 9056 4117 9044
      4095 9044
TIME...MOT...LOC 0418Z 286DEG 13KT 4101 9048 

HAIL...1.00IN
WIND...70MPH
 
$$

Ervin

155 
WWUS53 KDVN 190433
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1133 PM CDT Fri Jun 18 2021

ILC071-131-187-190443-
/O.CAN.KDVN.SV.W.0004.000000T0000Z-210619T0445Z/
Henderson IL-Warren IL-Mercer IL-
1133 PM CDT Fri Jun 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN HENDERSON...
NORTHERN WARREN AND SOUTHEASTERN MERCER COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area.  Therefore, the warning has been cancelled. However 
heavy rain is still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 500 AM CDT for
northwestern and west central Illinois...and southeastern Iowa.

Remember, a Severe Thunderstorm Warning still remains in effect for
much of Henderson and Warren Counties.

LAT...LON 4103 9094 4107 9095 4108 9056 4117 9044
      4095 9044
TIME...MOT...LOC 0432Z 271DEG 10KT 4101 9042 

$$

Ervin

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 18, 10:17 PM CDT	Severe Thunderstorm Warning	DVN	Henderson, Mercer	58 min
Jun 18, 11:02 PM CDT	Severe Thunderstorm Warning	DVN	Henderson, Warren	43 min
Jun 18, 11:36 PM CDT	Severe Thunderstorm Warning	DVN	Henderson, Warren	40 min
Jun 19, 1:28 AM CDT	Special Weather Statement	DVN	Warren	2 hr
Jun 19, 2:01 AM CDT	Special Weather Statement	DVN	Hancock, McDonough	59 min
Jun 19, 2:27 AM CDT	Special Weather Statement	DVN	McDonough	33 min
Jun 19, 4:33 AM CDT	Severe Thunderstorm Warning	DVN	Hancock	57 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2021 Every 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.