Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 67, NWS Quad Cities, IA

August 10, 2021Delaware County, Dubuque County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 10, 2021, 3:29 PM CDT for Delaware County, Dubuque County, Iowa. It was in force for 31 min. 1 report 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: Aug 10, 2021, 3:29 PM CDT (20:29 UTC)
Expired: Aug 10, 2021, 4:00 PM CDT
In force: 31 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Delaware County, IA, Dubuque County, IA

The radar

The Quad Cities radar (KDVN), 108 km from the middle of the area, began a volume at 20:29 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
Aug 10, 3:55 PM CDT	TSTM WND GST 60	3 N Hopkinton, IA	PUBLIC REPORT OF ESTIMATED 60 MPH WIND GUST. RELAYED BY COUNTY OFFICIAL.

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
Aug 10, 2:08 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 8.5 hours before the alert went out and 110 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.

196 
WUUS53 KDVN 102029
SVRDVN
IAC055-061-102100-
/O.NEW.KDVN.SV.W.0067.210810T2029Z-210810T2100Z/

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

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Northwestern Dubuque County in northeastern Iowa...
  Eastern Delaware County in northeastern Iowa...

* Until 400 PM CDT.

* At 329 PM CDT, a severe thunderstorm was located over Earlville, or
  11 miles east of Manchester, moving northeast at 20 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...
  Worthington around 340 PM CDT.

Other locations in the path of this severe thunderstorm include
Dyersville, New Vienna, Farley and Luxemburg.

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.

&&

LAT...LON 4240 9097 4234 9128 4251 9135 4265 9114
      4265 9104
TIME...MOT...LOC 2029Z 246DEG 19KT 4246 9123 

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

$$

Gunkel

1 follow-up statement

005 
WWUS53 KDVN 102045
SVSDVN

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

IAC055-061-102100-
/O.CON.KDVN.SV.W.0067.000000T0000Z-210810T2100Z/
Dubuque IA-Delaware IA-
345 PM CDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM CDT
FOR NORTHWESTERN DUBUQUE AND EASTERN DELAWARE COUNTIES...

At 344 PM CDT, a severe thunderstorm was located over Dyersville, or
16 miles east of Manchester, moving east at 20 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...
  Luxemburg and Farley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 4240 9097 4234 9128 4251 9135 4265 9114
      4265 9104
TIME...MOT...LOC 2044Z 270DEG 19KT 4249 9113 

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

$$

Gunkel

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, 3:49 PM CDT	Severe Thunderstorm Warning	DVN	Benton, Buchanan, Iowa	41 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.