Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 42, NWS Quad Cities, IA

July 9, 2021Lee County, Iowa; Clark County, Missouri; Hancock County, Illinois

NWS Quad Cities, IA issued this severe thunderstorm warning at Jul 9, 2021, 8:57 PM CDT for Lee County, Iowa; Clark County, Missouri; Hancock County, Illinois. It was in force for 33 min. 2 reports 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: Jul 9, 2021, 8:57 PM CDT (01:57 UTC)
Expired: Jul 9, 2021, 9:30 PM CDT
In force: 33 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Lee County, IA, Hancock County, IL, Clark County, MO

The radar

The Quad Cities radar (KDVN), 147 km from the middle of the area, began a volume at 01:57 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
Jul 9, 9:00 PM CDT	TSTM WND DMG	1 Se Keokuk, IA	TREE DOWN NEAR 16TH ST AND TIMEA ST.
Jul 9, 9:18 PM CDT	TSTM WND DMG	1 Se Keokuk, IA	CORRECTS PREVIOUS TSTM WND DMG REPORT FROM 1 SE KEOKUK. TREE DOWN NEAR 16TH ST AND TIMEA ST. SEVERAL 6 TO 10 INCH DIAMETER BRANCHES DOWN IN TOWN.

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
Jul 9, 7:08 PM CDT	Severe Thunderstorm Watch	SPC	3 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 2.0 hours before the alert went out and 152 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: 1111 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 19 m²/s²
0-3 km storm-relative helicity: 114 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

852 
WUUS53 KDVN 100157
SVRDVN
ILC067-IAC111-MOC045-100230-
/O.NEW.KDVN.SV.W.0042.210710T0157Z-210710T0230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
857 PM CDT Fri Jul 9 2021

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Northwestern Hancock County in west central Illinois...
  Western Lee County in southeastern Iowa...
  Central Clark County in northeastern Missouri...

* Until 930 PM CDT.

* At 857 PM CDT, a severe thunderstorm was located over Croton, or 11
  miles north of Kahoka, moving southeast at 40 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* This severe thunderstorm will be near...
  New Boston around 905 PM CDT.
  St. Francisville around 910 PM CDT.
  Wayland around 915 PM CDT.

Other locations in the path of this severe thunderstorm include
Keokuk, Warsaw and Alexandria.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and 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 4058 9180 4061 9172 4060 9172 4062 9170
      4064 9162 4073 9144 4046 9117 4033 9145
      4029 9169
TIME...MOT...LOC 0157Z 330DEG 33KT 4058 9165 

HAIL...1.00IN
WIND...60MPH
 
$$

Gibbs

3 follow-up statements

273 
WWUS53 KDVN 100159 RRA
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
859 PM CDT Fri Jul 9 2021

ILC067-IAC111-MOC045-100230-
/O.CON.KDVN.SV.W.0042.000000T0000Z-210710T0230Z/
Hancock IL-Lee IA-Clark MO-
859 PM CDT Fri Jul 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 PM CDT
FOR NORTHWESTERN HANCOCK...WESTERN LEE AND CENTRAL CLARK COUNTIES...

At 859 PM CDT, a severe thunderstorm was located near Croton, or 10
miles northeast of Kahoka, moving southeast at 40 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...
  New Boston around 905 PM CDT.
  Wayland and St. Francisville around 915 PM CDT.

Other locations in the path of this severe thunderstorm include
Keokuk, Warsaw and Alexandria.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm is producing large hail. SEEK SHELTER NOW inside a sturdy
structure and stay away from windows.

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 4058 9180 4061 9172 4060 9172 4062 9170
      4064 9162 4073 9144 4046 9117 4033 9145
      4029 9169
TIME...MOT...LOC 0159Z 330DEG 33KT 4056 9164 

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

Gibbs

821 
WWUS53 KDVN 100210
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
910 PM CDT Fri Jul 9 2021

ILC067-IAC111-MOC045-100230-
/O.CON.KDVN.SV.W.0042.000000T0000Z-210710T0230Z/
Hancock IL-Lee IA-Clark MO-
910 PM CDT Fri Jul 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 PM CDT
FOR NORTHWESTERN HANCOCK...SOUTHWESTERN LEE AND SOUTHEASTERN CLARK
COUNTIES...

At 910 PM CDT, a severe thunderstorm was located near St.
Francisville, or near Keokuk, moving southeast at 45 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe storm will be near...
  Keokuk around 915 PM CDT.

Other locations in the path of this severe thunderstorm include
Hamilton, Warsaw and Alexandria.

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.

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

&&

LAT...LON 4049 9173 4053 9160 4061 9151 4066 9138
      4046 9117 4033 9145 4029 9169
TIME...MOT...LOC 0210Z 324DEG 40KT 4044 9151 

HAIL...1.00IN
WIND...60MPH
 
$$

Gibbs

221 
WWUS53 KDVN 100223
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
923 PM CDT Fri Jul 9 2021

IAC111-ILC067-MOC045-100233-
/O.EXP.KDVN.SV.W.0042.000000T0000Z-210710T0230Z/
Hancock IL-Lee IA-Clark MO-
923 PM CDT Fri Jul 9 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN HANCOCK...
SOUTHWESTERN LEE AND SOUTHEASTERN CLARK COUNTIES WILL EXPIRE AT 930
PM CDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

A Severe Thunderstorm Watch remains in effect until midnight CDT for
west central Illinois...southeastern Iowa...and northeastern
Missouri.

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

LAT...LON 4049 9173 4053 9160 4061 9151 4066 9138
      4046 9117 4033 9145 4029 9169
TIME...MOT...LOC 0223Z 270DEG 33KT 4035 9144 

$$

Gibbs

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 9, 7:08 PM CDT	Severe Thunderstorm Warning	DVN	Des Moines, Henry, Lee	37 min
Jul 9, 7:19 PM CDT	Severe Thunderstorm Warning	DVN	Lee	41 min
Jul 9, 7:29 PM CDT	Severe Thunderstorm Warning	DVN	Iowa, Johnson, Keokuk, Louisa, Washington	31 min
Jul 9, 7:51 PM CDT	Severe Thunderstorm Warning	DVN	Henry, Jefferson, Keokuk, Washington	24 min
Jul 9, 8:25 PM CDT	Severe Thunderstorm Warning	DVN	Henry, Lee, Van Buren	35 min
Jul 10, 4:25 AM CDT	Special Weather Statement	DVN	Jefferson, Keokuk, Van Buren	95 min
Jul 9, 7:39 PM CDT	Severe Thunderstorm Warning	DVN	Hancock, Henderson, McDonough, Warren	66 min
Jul 9, 9:23 PM CDT	Special Weather Statement	DVN	Hancock	52 min
Jul 10, 2:21 AM CDT	River Flood Warning	DVN	Hancock, McDonough	28 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2021 Severe Thunderstorm Warnings in Missouri, 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.