Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 34, NWS Quad Cities, IA

July 9, 2021Des Moines County, Henry County, Louisa County, Iowa; Henderson County, Illinois

NWS Quad Cities, IA issued this severe thunderstorm warning at Jul 9, 2021, 6:23 PM CDT for Des Moines County, Henry County, Louisa County, Iowa; Henderson County, Illinois. It was in force for 37 min. 4 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, 6:23 PM CDT (23:23 UTC)
Expired
Jul 9, 2021, 7:00 PM CDT
In force
37 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Hail
1.75 in
Wind
50.0 mph

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

The radar

The Quad Cities radar (KDVN), 96 km from the middle of the area, began a volume at 23:24 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

TimeReportWhereRemark
Jul 9, 6:30 PM CDTHAIL 0.74 Wsw Mount Union, IAA FEW DIME SIZED HAIL STONES AND HEAVY RAIN. TIME ESTIMATED.
Jul 9, 6:31 PM CDTHAIL 1.5Mount Union, IA
Jul 9, 6:51 PM CDTHAIL 0.881 Ese New London, IANICKEL SIZED HAIL FOR ABOUT 2 MINUTES ENDING AROUND 653 PM.
Jul 9, 6:51 PM CDTHAIL 11 Se New London, IADIME TO QUARTER SIZED HAIL.

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

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.4 hours before the alert went out and 101 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-pSkew-T log-p diagram, Davenport, at 12:00Z on 2021-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 2021-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1131 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
100 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

921 
WUUS53 KDVN 092323
SVRDVN
ILC071-IAC057-087-115-100000-
/O.NEW.KDVN.SV.W.0034.210709T2323Z-210710T0000Z/

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

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Central Henderson County in west central Illinois...
  Northeastern Henry County in southeastern Iowa...
  Des Moines County in southeastern Iowa...
  South central Louisa County in southeastern Iowa...

* Until 700 PM CDT.

* At 623 PM CDT, a severe thunderstorm was located near Mount Union,
  or 9 miles east of Mount Pleasant, moving southeast at 45 mph.

  HAZARD...Golf ball size hail.

  SOURCE...Trained weather spotters.

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

* This severe thunderstorm will be near...
  Mediapolis and Danville around 635 PM CDT.

Other locations in the path of this severe thunderstorm include
Burlington, West Burlington and Gulf Port.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4100 9159 4115 9146 4093 9092 4072 9107
TIME...MOT...LOC 2323Z 299DEG 38KT 4100 9137 

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

DC
2 follow-up statements
207 
WWUS53 KDVN 092333
SVSDVN

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

IAC115-092342-
/O.CAN.KDVN.SV.W.0034.000000T0000Z-210710T0000Z/
Louisa IA-
633 PM CDT Fri Jul 9 2021

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

LAT...LON 4099 9143 4109 9137 4108 9137 4107 9130
      4093 9092 4072 9107
TIME...MOT...LOC 2332Z 299DEG 38KT 4095 9125 

$$

ILC071-IAC057-087-100000-
/O.CON.KDVN.SV.W.0034.000000T0000Z-210710T0000Z/
Henderson IL-Henry IA-Des Moines IA-
633 PM CDT Fri Jul 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM CDT
FOR CENTRAL HENDERSON...EAST CENTRAL HENRY AND CENTRAL DES MOINES
COUNTIES...

At 632 PM CDT, a severe thunderstorm was located near Mediapolis, or
11 miles northwest of Burlington, moving southeast at 45 mph.

HAZARD...Golf ball size hail.

SOURCE...Trained weather spotters.

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

Locations impacted include...
  Burlington, West Burlington and Gulf Port.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4099 9143 4109 9137 4108 9137 4107 9130
      4093 9092 4072 9107
TIME...MOT...LOC 2332Z 299DEG 38KT 4095 9125 

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

DC
355 
WWUS53 KDVN 092343
SVSDVN

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

ILC071-IAC057-087-100000-
/O.CON.KDVN.SV.W.0034.000000T0000Z-210710T0000Z/
Henderson IL-Henry IA-Des Moines IA-
643 PM CDT Fri Jul 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM CDT
FOR CENTRAL HENDERSON...EAST CENTRAL HENRY AND CENTRAL DES MOINES
COUNTIES...

At 643 PM CDT, a severe thunderstorm was located near West
Burlington, or near Burlington, moving southeast at 45 mph.

HAZARD...Ping pong ball size hail.

SOURCE...Trained weather spotters.

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

Locations impacted include...
Burlington, Oquawka, West Burlington, Mediapolis, Carman, Mount
Union, Gulf Port, Lone Tree, Carthage Lake, Shokokon, Heapsville,
Starr's Cave Park and Preserve, Burlington Regional Airport, Sperry,
Prairie Grove, Big Hollow Recreation Area, Pleasant Grove,
Dodgeville, Beaverdale and Des Moines County Fairgrounds.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4099 9143 4109 9137 4108 9137 4107 9130
      4093 9092 4072 9107
TIME...MOT...LOC 2343Z 299DEG 38KT 4089 9112 

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

DC

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 2:49 AM CDTFlash Flood WatchDVNDes Moines, Henry, Jefferson, Lee, Van Buren40 hr
Jul 9, 5:04 PM CDTSpecial Weather StatementDVNIowa26 min
Jul 9, 5:16 PM CDTSevere Thunderstorm WarningDVNIowa, Johnson, Keokuk, Washington29 min
Jul 9, 5:34 PM CDTSpecial Weather StatementDVNBenton26 min
Jul 9, 5:59 PM CDTSpecial Weather StatementDVNBenton, Des Moines, Henry, Iowa, Jefferson, Johnson and 3 more31 min
Jul 9, 6:07 PM CDTSevere Thunderstorm WarningDVNHenry, Washington23 min
Jul 9, 6:37 PM CDTSpecial Weather StatementDVNIowa23 min
Jul 9, 6:50 PM CDTSevere Thunderstorm WarningDVNDes Moines, Henry25 min
Jul 9, 8:58 AM CDTRiver Flood WatchDVNHancock, McDonough17 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2021Severe Thunderstorm Warnings in Illinois, 2021Every 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.