Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 93, NWS Quad Cities, IA

August 24, 2021Benton County, Iowa County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 24, 2021, 5:05 PM CDT for Benton County, Iowa County, Iowa. It was in force for 40 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
Aug 24, 2021, 5:05 PM CDT (22:05 UTC)
Expired
Aug 24, 2021, 5:45 PM CDT
In force
40 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Benton County, IA, Iowa County, IA

The radar

The Quad Cities radar (KDVN), 137 km from the middle of the area, began a volume at 22:06 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.

IssuedProductOfficeLasted
Aug 24, 1:52 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.1 hours before the alert went out and 143 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 2021-08-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1809 joules per kilogram.LCLLFCEL10008507005003002001001 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 2021-08-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 35 square meters per square second.193958Sfc1 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
1809 J/kg
Mixed-layer CIN
-127 J/kg
Mixed-layer LCL
1284 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
9 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

281 
WUUS53 KDVN 242205
SVRDVN
IAC011-095-242245-
/O.NEW.KDVN.SV.W.0093.210824T2205Z-210824T2245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
505 PM CDT Tue Aug 24 2021

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Benton County in east central Iowa...
  Northern Iowa County in east central Iowa...

* Until 545 PM CDT.

* At 504 PM CDT, severe thunderstorms were located along a line
  extending from near La Porte City to near Van Horne to near Belle
  Plaine, moving east at 50 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Severe thunderstorms will be near...
  Van Horne around 510 PM CDT.
  Newhall and Garrison around 515 PM CDT.
  Vinton, Marengo, Shellsburg and Norway around 520 PM CDT.

Other locations in the path of these severe thunderstorms include
Atkins, Walford, Urbana and Amana.

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 these storms.
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 these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4229 9230 4229 9183 4173 9183 4183 9230
TIME...MOT...LOC 2204Z 284DEG 44KT 4229 9228 4205 9215 4183 9229 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gibbs
3 follow-up statements
225 
WWUS53 KDVN 242215
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
515 PM CDT Tue Aug 24 2021

IAC011-095-242245-
/O.CON.KDVN.SV.W.0093.000000T0000Z-210824T2245Z/
Benton IA-Iowa IA-
515 PM CDT Tue Aug 24 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM CDT
FOR BENTON AND NORTHERN IOWA COUNTIES...

At 514 PM CDT, severe thunderstorms were located along a line
extending from Mount Auburn to near Newhall to near Marengo, moving
east at 50 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

These severe storms will be near...
  Shellsburg, Newhall and Norway around 520 PM CDT.
  Atkins and Walford around 525 PM CDT.

Other locations in the path of these severe thunderstorms include
Urbana and Amana.

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 these storms.
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 these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4229 9230 4229 9183 4173 9183 4183 9230
TIME...MOT...LOC 2214Z 284DEG 44KT 4226 9212 4202 9199 4180 9213 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gibbs
738 
WWUS53 KDVN 242231
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
531 PM CDT Tue Aug 24 2021

IAC011-095-242245-
/O.CON.KDVN.SV.W.0093.000000T0000Z-210824T2245Z/
Benton IA-Iowa IA-
531 PM CDT Tue Aug 24 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM CDT
FOR BENTON AND NORTHERN IOWA COUNTIES...

At 531 PM CDT, severe thunderstorms were located along a line
extending from near Vinton to Walford to near Williamsburg, moving
southeast at 45 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

These severe storms will be near...
  Amana around 535 PM CDT.

Other locations in the path of these severe thunderstorms include
Atkins.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Continuous cloud to ground lightning is occurring with these storms.
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 these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4229 9183 4173 9183 4183 9230 4201 9230
      4202 9216 4229 9213
TIME...MOT...LOC 2231Z 293DEG 38KT 4213 9195 4189 9182 4167 9196 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gibbs
433 
WWUS53 KDVN 242242
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
542 PM CDT Tue Aug 24 2021

IAC011-095-242251-
/O.EXP.KDVN.SV.W.0093.000000T0000Z-210824T2245Z/
Benton IA-Iowa IA-
542 PM CDT Tue Aug 24 2021

...THE SEVERE THUNDERSTORM WARNING FOR BENTON AND NORTHERN IOWA
COUNTIES WILL EXPIRE AT 545 PM CDT...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with these thunderstorms.

A Severe Thunderstorm Watch remains in effect until 700 PM CDT for
east central Iowa.

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 4229 9183 4173 9183 4183 9230 4201 9230
      4202 9216 4229 9213
TIME...MOT...LOC 2241Z 284DEG 44KT 4210 9181 4186 9168 4164 9182 

$$

Gibbs

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 24, 2:21 PM CDTSevere Thunderstorm WarningDVNBuchanan39 min
Aug 24, 2:49 PM CDTSevere Thunderstorm Warning Considerable damage threatDVNBenton, Buchanan, Delaware, Jones, Linn56 min
Aug 24, 3:03 PM CDTSevere Thunderstorm Warning Destructive damage threatDVNBuchanan, Delaware, Dubuque42 min
Aug 24, 3:38 PM CDTTornado WarningDVNDubuque25 min
Aug 24, 3:42 PM CDTSevere Thunderstorm Warning Destructive damage threatDVNDelaware, Dubuque48 min
Aug 24, 4:07 PM CDTSpecial Weather StatementDVNCedar, Clinton, Jackson, Johnson23 min
Aug 24, 4:17 PM CDTSevere Thunderstorm Warning Considerable damage threatDVNDubuque, Jackson58 min
Aug 24, 4:54 PM CDTSpecial Weather StatementDVNBenton36 min
Aug 24, 5:01 PM CDTSevere Thunderstorm WarningDVNJackson59 min
Aug 24, 5:23 PM CDTSevere Thunderstorm WarningDVNClinton, Scott37 min
Aug 24, 5:27 PM CDTSpecial Weather StatementDVNJohnson48 min
Aug 24, 6:07 PM CDTSevere Thunderstorm WarningDVNCedar, Johnson, Linn38 min
Aug 24, 6:49 PM CDTSpecial Weather StatementDVNScott41 min

Nearby

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