Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 68, NWS Quad Cities, IA

August 10, 2021Benton County, Buchanan County, Iowa County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 10, 2021, 3:49 PM CDT for Benton County, Buchanan County, Iowa County, Iowa. It was in force for 41 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 10, 2021, 3:49 PM CDT (20:49 UTC)
Expired: Aug 10, 2021, 4:30 PM CDT
In force: 41 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Benton County, IA, Buchanan County, IA, Iowa County, IA

The radar

The Quad Cities radar (KDVN), 141 km from the middle of the area, began a volume at 20:51 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
Aug 10, 2:08 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 8.8 hours before the alert went out and 147 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: 3755 J/kg
Mixed-layer CIN: -67 J/kg
Mixed-layer LCL: 819 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: -37 m²/s²
0-3 km storm-relative helicity: 4 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

433 
WUUS53 KDVN 102049
SVRDVN
IAC011-019-095-102145-
/O.NEW.KDVN.SV.W.0068.210810T2049Z-210810T2145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
349 PM CDT Tue Aug 10 2021

The National Weather Service in the Quad Cities has issued a

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

* Until 445 PM CDT.

* At 349 PM CDT, severe thunderstorms were located along a line
  extending from Walker to 7 miles southwest of Tama, moving east at
  25 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.

* Severe thunderstorms will be near...
  Urbana and Rowley around 355 PM CDT.

Other locations in the path of these severe thunderstorms include
Belle Plaine, Luzerne, Blairstown, Van Horne and Keystone.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4230 9230 4230 9206 4244 9206 4243 9183
      4178 9183 4178 9230
TIME...MOT...LOC 2049Z 260DEG 23KT 4230 9181 4187 9263 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Speck

3 follow-up statements

946 
WWUS53 KDVN 102100
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
400 PM CDT Tue Aug 10 2021

IAC011-019-095-102145-
/O.CON.KDVN.SV.W.0068.000000T0000Z-210810T2145Z/
Buchanan IA-Benton IA-Iowa IA-
400 PM CDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM CDT
FOR SOUTHWESTERN BUCHANAN...BENTON AND NORTHERN IOWA COUNTIES...

At 400 PM CDT, severe thunderstorms were located along a line
extending from near Troy Mills to near Tama, moving east at 25 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.

Locations impacted include...
  Belle Plaine, Luzerne, Marengo, Blairstown and Norway.

LAT...LON 4230 9230 4230 9206 4244 9206 4243 9183
      4178 9183 4178 9230
TIME...MOT...LOC 2100Z 270DEG 23KT 4231 9173 4188 9255 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Speck

385 
WWUS53 KDVN 102117
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
417 PM CDT Tue Aug 10 2021

IAC011-019-095-102145-
/O.CON.KDVN.SV.W.0068.000000T0000Z-210810T2145Z/
Buchanan IA-Benton IA-Iowa IA-
417 PM CDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM CDT
FOR SOUTHWESTERN BUCHANAN...BENTON AND NORTHERN IOWA COUNTIES...

At 416 PM CDT, severe thunderstorms were located along a line
extending from near Coggon to 7 miles west of Belle Plaine, moving
east at 25 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.

Locations impacted include...
Vinton, Marengo, Belle Plaine, Atkins, Walford, Urbana, Dysart,
Shellsburg, Newhall, Blairstown, Van Horne, Keystone, Norway,
Garrison, Brandon, Rowley, Mount Auburn, Luzerne, Amana and Middle
Amana.

LAT...LON 4230 9230 4230 9206 4244 9206 4243 9183
      4178 9183 4178 9230
TIME...MOT...LOC 2116Z 260DEG 23KT 4233 9159 4190 9241 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Speck

856 
WWUS53 KDVN 102130
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
430 PM CDT Tue Aug 10 2021

IAC011-019-095-102140-
/O.CAN.KDVN.SV.W.0068.000000T0000Z-210810T2145Z/
Buchanan IA-Benton IA-Iowa IA-
430 PM CDT Tue Aug 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN BUCHANAN...BENTON
AND NORTHERN IOWA COUNTIES IS CANCELLED...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 800 PM CDT for
northeastern and east central Iowa.

LAT...LON 4230 9230 4230 9206 4244 9206 4243 9183
      4178 9183 4178 9230
TIME...MOT...LOC 2127Z 260DEG 23KT 4234 9150 4191 9232 

$$

Speck

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 10, 2:28 PM CDT	Heat Advisory	DVN	Benton, Buchanan, Cedar, Clinton, Delaware, Des Moines and 15 more	29 hr
Aug 10, 2:33 PM CDT	Special Weather Statement	DVN	Buchanan	27 min
Aug 10, 2:42 PM CDT	Special Weather Statement	DVN	Benton	33 min
Aug 10, 2:55 PM CDT	Severe Thunderstorm Warning	DVN	Buchanan	50 min
Aug 10, 3:07 PM CDT	Severe Thunderstorm Warning	DVN	Delaware, Dubuque	23 min
Aug 10, 3:25 PM CDT	Severe Thunderstorm Warning	DVN	Buchanan, Delaware, Linn	50 min
Aug 10, 3:29 PM CDT	Severe Thunderstorm Warning	DVN	Delaware, Dubuque	31 min
Aug 10, 4:04 PM CDT	Severe Thunderstorm Warning	DVN	Delaware, Dubuque, Jackson, Jones, Linn	56 min
Aug 10, 4:28 PM CDT	Severe Thunderstorm Warning	DVN	Benton, Buchanan, Delaware, Linn	36 min
Aug 10, 4:38 PM CDT	Severe Thunderstorm Warning	DVN	Cedar, Jackson, Jones, Linn	52 min
Aug 10, 5:00 PM CDT	Severe Thunderstorm Warning	DVN	Clinton, Jackson, Jones	45 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.