Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 69, NWS Quad Cities, IA

August 10, 20215 counties in Iowa; Jo Daviess County, Illinois

NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 10, 2021, 4:04 PM CDT for 5 counties in Iowa; Jo Daviess County, Illinois. It was in force for 56 min. 3 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: Aug 10, 2021, 4:04 PM CDT (21:04 UTC)
Expired: Aug 10, 2021, 5:00 PM CDT
In force: 56 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Delaware County, IA, Dubuque County, IA, Jackson County, IA, Jones County, IA, Linn County, IA, Jo Daviess County, IL

The radar

The Quad Cities radar (KDVN), 105 km from the middle of the area, began a volume at 21:03 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, 4:18 PM CDT	TSTM WND GST 48	Dubuque Regional Arpt, IA	ASOS.
Aug 10, 4:20 PM CDT	TSTM WND DMG	Prairieburg, IA	DELAYED REPORT. LARGE TREE DOWN ALONG WITH POWER LINES.
Aug 10, 4:27 PM CDT	HAIL 0.7	2 Ne Dubuque, IA	OCCURRING NOW.

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
Aug 10, 3:47 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 9.1 hours before the alert went out and 106 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.

216 
WUUS53 KDVN 102104
SVRDVN
ILC085-IAC055-061-097-105-113-102200-
/O.NEW.KDVN.SV.W.0069.210810T2104Z-210810T2200Z/

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

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Northwestern Jo Daviess County in northwestern Illinois...
  Northwestern Jackson County in east central Iowa...
  Dubuque County in northeastern Iowa...
  Northern Jones County in east central Iowa...
  Delaware County in northeastern Iowa...
  Northern Linn County in east central Iowa...

* Until 500 PM CDT.

* At 403 PM CDT, severe thunderstorms were located along a line
  extending from Sherrill to near Monticello, moving east at 35 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Severe thunderstorms will be near...
  Dubuque, Asbury, Rickardsville, Sherrill, Sageville and Durango 
  around 410 PM CDT.
  East Dubuque around 420 PM CDT.

Other locations in the path of these severe thunderstorms include
Cascade, Menominee, Bernard, Canton, Zwingle and La Motte.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4267 9086 4264 9071 4251 9064 4251 9032
      4215 9082 4213 9176 4265 9125 4265 9090
      4267 9090
TIME...MOT...LOC 2103Z 275DEG 30KT 4260 9079 4226 9128 

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

$$

Uttech

2 follow-up statements

317 
WWUS53 KDVN 102118
SVSDVN

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

ILC085-IAC055-061-097-105-113-102200-
/O.CON.KDVN.SV.W.0069.000000T0000Z-210810T2200Z/
Jo Daviess IL-Jackson IA-Dubuque IA-Jones IA-Delaware IA-Linn IA-
418 PM CDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 500 PM CDT
FOR NORTHWESTERN JO DAVIESS...NORTHWESTERN JACKSON...DUBUQUE...
NORTHERN JONES...SOUTHERN DELAWARE AND NORTHERN LINN COUNTIES...

At 417 PM CDT, severe thunderstorms were located along a line
extending from Durango to near Cascade to near Stone City, moving
east at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
  Dubuque, Asbury, East Dubuque, Sherrill, Sageville, Bernard, 
  Durango, Menominee, Zwingle, Galena, La Motte, St. Donatus and 
  Canton.

LAT...LON 4267 9086 4264 9071 4251 9064 4251 9032
      4215 9082 4213 9176 4242 9147 4265 9101
      4265 9090 4267 9090
TIME...MOT...LOC 2117Z 276DEG 36KT 4255 9076 4233 9095 4215 9135 

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

$$

Uttech

702 
WWUS53 KDVN 102142
SVSDVN

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

ILC085-IAC055-061-097-105-113-102200-
/O.CON.KDVN.SV.W.0069.000000T0000Z-210810T2200Z/
Jo Daviess IL-Jackson IA-Dubuque IA-Jones IA-Delaware IA-Linn IA-
442 PM CDT Tue Aug 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 500 PM CDT
FOR NORTHWESTERN JO DAVIESS...NORTHWESTERN JACKSON...SOUTHEASTERN
DUBUQUE...NORTHERN JONES...SOUTHERN DELAWARE AND NORTHERN LINN
COUNTIES...

At 442 PM CDT, severe thunderstorms were located along a line
extending from Menominee to near Zwingle to Center Junction, moving
east at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Trained weather spotters.

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

Locations impacted include...
Dubuque, Galena, Asbury, Monticello, Cascade, Epworth, East Dubuque,
Farley, Peosta, Central City, Alburnett, Coggon, Hopkinton,
Worthington, Ryan, La Motte, Menominee, Prairieburg, St. Donatus and
Centralia.

LAT...LON 4251 9064 4251 9032 4215 9082 4213 9176
      4241 9146 4245 9087 4264 9072 4264 9071
TIME...MOT...LOC 2142Z 284DEG 30KT 4249 9050 4226 9070 4213 9109 

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

$$

Uttech

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, 3:49 PM CDT	Severe Thunderstorm Warning	DVN	Benton, Buchanan, Iowa	41 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
Aug 9, 7:12 PM CDT	Tornado Warning Tornado observed	DVN	Bureau	48 min
Aug 9, 7:30 PM CDT	Tornado Warning Tornado observed	DVN	Bureau	45 min
Aug 9, 8:02 PM CDT	Flash Flood Warning	DVN	Bureau	2 hr
Aug 9, 8:16 PM CDT	Severe Thunderstorm Warning	DVN	Bureau, Putnam	29 min
Aug 9, 9:39 PM CDT	Special Weather Statement	DVN	Henry	36 min
Aug 9, 9:54 PM CDT	Special Weather Statement	DVN	Henry	51 min
Aug 9, 10:44 PM CDT	Special Weather Statement	DVN	Mercer	31 min
Aug 10, 5:24 PM CDT	Severe Thunderstorm Warning	DVN	Carroll, Jo Daviess, Stephenson, Whiteside	51 min
Aug 10, 5:47 PM CDT	Special Weather Statement	DVN	Bureau	13 min
Aug 10, 5:47 PM CDT	Special Weather Statement	DVN	Bureau	13 min
Aug 10, 5:49 PM CDT	Severe Thunderstorm Warning	DVN	Stephenson	41 min
Aug 10, 6:16 PM CDT	Severe Thunderstorm Warning	DVN	Stephenson	13 min
Aug 10, 6:50 PM CDT	Severe Thunderstorm Warning	DVN	Bureau	25 min
Aug 10, 6:53 PM CDT	Special Weather Statement	DVN	Mercer, Warren	37 min

Nearby

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