Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 3, NWS Quad Cities, IA

June 18, 2021Henderson County, Mercer County, Illinois; 4 counties in Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Jun 18, 2021, 10:17 PM CDT for Henderson County, Mercer County, Illinois; 4 counties in Iowa. It was in force for 58 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, 10:17 PM CDT (03:17 UTC)
Expired: Jun 18, 2021, 11:15 PM CDT
In force: 58 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 1.5 in
Wind: 50.0 mph

Counties Des Moines County, IA, Henry County, IA, Louisa County, IA, Washington County, IA, Henderson County, IL, Mercer County, IL

The radar

The Quad Cities radar (KDVN), 69 km from the middle of the area, began a volume at 03:21 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, 10:40 PM CDT	HAIL 0.25	Wapello, IA	PEA SIZE HAIL AT THE SHEFIFF'S OFFICE.

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, 3.3 hours before the alert went out and 75 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.

346 
WUUS53 KDVN 190317
SVRDVN
ILC071-131-IAC057-087-115-183-190415-
/O.NEW.KDVN.SV.W.0003.210619T0317Z-210619T0415Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
1017 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...
  Western Mercer County in northwestern Illinois...
  Northeastern Henry County in southeastern Iowa...
  Northeastern Des Moines County in southeastern Iowa...
  Louisa County in southeastern Iowa...
  Southeastern Washington County in southeastern Iowa...

* Until 1115 PM CDT.

* At 1016 PM CDT, a severe thunderstorm was located over Wyman, or
  near Columbus Junction, moving east at 40 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.

* This severe thunderstorm will be near...
  Columbus Junction and Columbus City around 1020 PM CDT.
  Wapello, Morning Sun and Grandview around 1035 PM CDT.

Other locations in the path of this severe thunderstorm include
Amber, Oakville, Toolesboro, New Boston, Mannon, Keithsburg, Joy,
Millersburg and Seaton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 4138 9176 4127 9076 4107 9076 4107 9079
      4101 9079 4117 9171
TIME...MOT...LOC 0316Z 276DEG 33KT 4121 9144 

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

Ervin

5 follow-up statements

074 
WWUS53 KDVN 190322
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1022 PM CDT Fri Jun 18 2021

ILC071-131-IAC057-087-115-183-190415-
/O.CON.KDVN.SV.W.0003.000000T0000Z-210619T0415Z/
Henderson IL-Mercer IL-Henry IA-Des Moines IA-Louisa IA-
Washington IA-
1022 PM CDT Fri Jun 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM CDT
FOR NORTHEASTERN HENDERSON...WESTERN MERCER...NORTHEASTERN HENRY...
NORTHEASTERN DES MOINES...LOUISA AND SOUTHEASTERN WASHINGTON
COUNTIES...

At 1021 PM CDT, a severe thunderstorm was located near Columbus City,
or near Columbus Junction, moving east at 35 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.

This severe storm will be near...
  Morning Sun around 1035 PM CDT.

Other locations in the path of this severe thunderstorm include
Wapello, Grandview, Amber, Toolesboro, Oakville, New Boston,
Keithsburg, Mannon, Joy, Aledo, Millersburg and Seaton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 4138 9176 4127 9076 4107 9076 4107 9079
      4101 9079 4117 9171
TIME...MOT...LOC 0321Z 273DEG 30KT 4122 9140 

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

Ervin

650 
WWUS53 KDVN 190330
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1030 PM CDT Fri Jun 18 2021

IAC087-190340-
/O.CAN.KDVN.SV.W.0003.000000T0000Z-210619T0415Z/
Henry IA-
1030 PM CDT Fri Jun 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN HENRY 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 500 AM CDT for
northwestern and west central Illinois...and southeastern and east
central Iowa.

LAT...LON 4127 9076 4107 9076 4107 9079 4101 9079
      4115 9137 4116 9137 4116 9143 4137 9164
TIME...MOT...LOC 0330Z 272DEG 31KT 4122 9132 

$$

ILC071-131-IAC057-115-183-190415-
/O.CON.KDVN.SV.W.0003.000000T0000Z-210619T0415Z/
Henderson IL-Mercer IL-Des Moines IA-Louisa IA-Washington IA-
1030 PM CDT Fri Jun 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM CDT
FOR NORTHEASTERN HENDERSON...WESTERN MERCER...NORTHEASTERN DES
MOINES...LOUISA AND EAST CENTRAL WASHINGTON COUNTIES...

At 1030 PM CDT, a severe thunderstorm was located near Columbus City,
or near Columbus Junction, moving east at 35 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.

This severe storm will be near...
  Wapello and Grandview around 1040 PM CDT.

Other locations in the path of this severe thunderstorm include
Amber, Oakville, Toolesboro, New Boston, Keithsburg, Mannon, Joy,
Millersburg, Aledo and Seaton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 4127 9076 4107 9076 4107 9079 4101 9079
      4115 9137 4116 9137 4116 9143 4137 9164
TIME...MOT...LOC 0330Z 272DEG 31KT 4122 9132 

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

Ervin

754 
WWUS53 KDVN 190338
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1038 PM CDT Fri Jun 18 2021

ILC071-IAC057-190348-
/O.CAN.KDVN.SV.W.0003.000000T0000Z-210619T0415Z/
Henderson IL-Des Moines IA-
1038 PM CDT Fri Jun 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN HENDERSON AND
NORTHEASTERN DES MOINES COUNTIES 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 500 AM CDT for
northwestern and west central Illinois...and southeastern and east
central Iowa.

LAT...LON 4127 9076 4107 9076 4107 9094 4115 9137
      4116 9137 4116 9143 4136 9153
TIME...MOT...LOC 0338Z 276DEG 33KT 4121 9121 

$$

ILC131-IAC115-183-190415-
/O.CON.KDVN.SV.W.0003.000000T0000Z-210619T0415Z/
Mercer IL-Louisa IA-Washington IA-
1038 PM CDT Fri Jun 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM CDT
FOR WESTERN MERCER...LOUISA AND EAST CENTRAL WASHINGTON COUNTIES...

At 1038 PM CDT, a severe thunderstorm was located over Wapello,
moving east at 40 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.

This severe storm will be near...
  Toolesboro around 1050 PM CDT.

Other locations in the path of this severe thunderstorm include New
Boston, Oakville, Keithsburg, Mannon, Joy, Millersburg, Aledo and
Seaton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4127 9076 4107 9076 4107 9094 4115 9137
      4116 9137 4116 9143 4136 9153
TIME...MOT...LOC 0338Z 276DEG 33KT 4121 9121 

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

Ervin

456 
WWUS53 KDVN 190348
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1048 PM CDT Fri Jun 18 2021

IAC183-190358-
/O.CAN.KDVN.SV.W.0003.000000T0000Z-210619T0415Z/
Washington IA-
1048 PM CDT Fri Jun 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL WASHINGTON 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 500 AM CDT for
northwestern and west central Illinois...and southeastern Iowa.

LAT...LON 4127 9076 4107 9076 4107 9094 4114 9116
      4119 9128 4120 9133 4132 9136
TIME...MOT...LOC 0348Z 271DEG 31KT 4122 9111 

$$

ILC131-IAC115-190415-
/O.CON.KDVN.SV.W.0003.000000T0000Z-210619T0415Z/
Mercer IL-Louisa IA-
1048 PM CDT Fri Jun 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM CDT
FOR WESTERN MERCER AND CENTRAL LOUISA COUNTIES...

At 1048 PM CDT, a severe thunderstorm was located near Wapello,
moving east at 35 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...
  New Boston, Keithsburg, Mannon, Joy, Millersburg, Seaton and 
  Aledo.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4127 9076 4107 9076 4107 9094 4114 9116
      4119 9128 4120 9133 4132 9136
TIME...MOT...LOC 0348Z 271DEG 31KT 4122 9111 

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

Ervin

464 
WWUS53 KDVN 190405
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
1105 PM CDT Fri Jun 18 2021

IAC115-ILC131-190415-
/O.EXP.KDVN.SV.W.0003.000000T0000Z-210619T0415Z/
Mercer IL-Louisa IA-
1105 PM CDT Fri Jun 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN MERCER AND CENTRAL
LOUISA COUNTIES WILL EXPIRE AT 1115 PM CDT...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area.  Therefore, the warning will be allowed to expire. 
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.

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

Remember, a Severe Thunderstorm Warning still remains in effect for
eastern Mercer County.

LAT...LON 4127 9076 4107 9076 4107 9094 4114 9116
      4119 9128 4120 9133 4132 9136
TIME...MOT...LOC 0405Z 276DEG 33KT 4121 9094 

$$

Ervin

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 18, 10:45 PM CDT	Severe Thunderstorm Warning	DVN	Henderson, Mercer, Warren	48 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
Jun 18, 11:03 PM CDT	Severe Thunderstorm Warning	DVN	Des Moines	27 min
Jun 18, 11:21 PM CDT	Severe Thunderstorm Warning	DVN	Henry, Jefferson	39 min
Jun 18, 11:29 PM CDT	Severe Thunderstorm Warning	DVN	Des Moines, Henry, Louisa	46 min
Jun 18, 11:47 PM CDT	Severe Thunderstorm Warning	DVN	Louisa, Washington	29 min
Jun 19, 12:02 AM CDT	Severe Thunderstorm Warning	DVN	Keokuk, Washington	43 min
Jun 19, 12:12 AM CDT	Severe Thunderstorm Warning	DVN	Jefferson, Keokuk, Van Buren, Washington	48 min
Jun 19, 12:27 AM CDT	Severe Thunderstorm Warning	DVN	Des Moines, Louisa	27 min
Jun 19, 1:08 AM CDT	Severe Thunderstorm Warning	DVN	Lee, Van Buren	49 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2021 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.