Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 40, NWS Quad Cities, IA

July 9, 20214 counties in Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Jul 9, 2021, 7:51 PM CDT for 4 counties in Iowa. It was in force for 24 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: Jul 9, 2021, 7:51 PM CDT (00:51 UTC)
Expired: Jul 9, 2021, 8:15 PM CDT
In force: 24 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Henry County, IA, Jefferson County, IA, Keokuk County, IA, Washington County, IA

The radar

The Quad Cities radar (KDVN), 112 km from the middle of the area, began a volume at 00:53 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
Jul 9, 7:08 PM CDT	Severe Thunderstorm Watch	SPC	3 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 0.9 hours before the alert went out and 118 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.

466 
WUUS53 KDVN 100051
SVRDVN
IAC087-101-107-183-100115-
/O.NEW.KDVN.SV.W.0040.210710T0051Z-210710T0115Z/

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

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Northern Henry County in southeastern Iowa...
  Southeastern Keokuk County in southeastern Iowa...
  Southern Washington County in southeastern Iowa...
  Eastern Jefferson County in southeastern Iowa...

* Until 815 PM CDT.

* At 751 PM CDT, a severe thunderstorm was located near Washington,
  moving south 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...
  Brighton around 755 PM CDT.
  Wayland, Pleasant Plain and Coppock around 800 PM CDT.
  Lockridge around 810 PM CDT.

Other locations in the path of this severe thunderstorm include Mount
Pleasant, Rome and Westwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4133 9201 4142 9168 4098 9143 4092 9188
TIME...MOT...LOC 0051Z 344DEG 42KT 4125 9177 

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

DC

2 follow-up statements

881 
WWUS53 KDVN 100100
SVSDVN

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

IAC107-100110-
/O.CAN.KDVN.SV.W.0040.000000T0000Z-210710T0115Z/
Keokuk IA-
800 PM CDT Fri Jul 9 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN KEOKUK 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 midnight CDT for
southeastern Iowa.

LAT...LON 4135 9164 4098 9143 4092 9188 4121 9195
TIME...MOT...LOC 0100Z 344DEG 42KT 4114 9173 

$$

IAC087-101-183-100115-
/O.CON.KDVN.SV.W.0040.000000T0000Z-210710T0115Z/
Henry IA-Washington IA-Jefferson IA-
800 PM CDT Fri Jul 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM CDT
FOR NORTHERN HENRY...SOUTHERN WASHINGTON AND EASTERN JEFFERSON
COUNTIES...

At 800 PM CDT, a severe thunderstorm was located over Coppock, or 10
miles south of Washington, moving south at 50 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...
  Lockridge around 810 PM CDT.

Other locations in the path of this severe thunderstorm include Mount
Pleasant, Rome and Westwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4135 9164 4098 9143 4092 9188 4121 9195
TIME...MOT...LOC 0100Z 344DEG 42KT 4114 9173 

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

DC

644 
WWUS53 KDVN 100111
SVSDVN

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

IAC087-101-183-100121-
/O.EXP.KDVN.SV.W.0040.000000T0000Z-210710T0115Z/
Henry IA-Washington IA-Jefferson IA-
811 PM CDT Fri Jul 9 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN HENRY...SOUTHERN
WASHINGTON AND EASTERN JEFFERSON COUNTIES WILL EXPIRE AT 815 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 midnight CDT for
southeastern Iowa.

LAT...LON 4135 9164 4098 9143 4092 9188 4121 9195
TIME...MOT...LOC 0111Z 344DEG 42KT 4103 9169 

$$

DC

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, 8:25 PM CDT	Severe Thunderstorm Warning	DVN	Henry, Lee, Van Buren	35 min
Jul 9, 8:57 PM CDT	Severe Thunderstorm Warning	DVN	Lee	33 min
Jul 10, 4:25 AM CDT	Special Weather Statement	DVN	Jefferson, Keokuk, Van Buren	95 min

Nearby

Severe Thunderstorm Warnings in Iowa, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.