Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 112, NWS Quad Cities, IA

December 15, 20216 counties in Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Dec 15, 2021, 8:08 PM CST for 6 counties in Iowa. It was in force for 67 min. 12 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: Dec 15, 2021, 8:08 PM CST (02:08 UTC)
Expired: Dec 15, 2021, 9:15 PM CST
In force: 67 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Tornado: Possible
Damage threat: Considerable
Hail: 0.75 in
Wind: 70.0 mph

Counties Buchanan County, IA, Delaware County, IA, Johnson County, IA, Linn County, IA, Louisa County, IA, Washington County, IA

The radar

The Quad Cities radar (KDVN), 85 km from the middle of the area, began a volume at 02:07 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
Dec 15, 8:30 PM CST	TSTM WND GST 66	Cedar Rapids Municipali, IA
Dec 15, 8:32 PM CST	TSTM WND DMG	1 E Tiffin, IA	THUNDERSTORM WINDS THREW TRAMPOLINE AGAINST HOUSE, CAUSING A METAL POLE TO PIERCE THE SIDING AND ENTER THE HOUSE. TIME IS ESTIMATED BY RADAR.
Dec 15, 8:38 PM CST	TSTM WND GST 80	Hiawatha, IA	CORRECTS THE TIME FROM THE PREVIOUS TSTM WND GST REPORT FROM HIAWATHA. SPOTTERR ESTIMATED WIND GUST OF 80 MPH BUT NO WAS DAMAGE NOTED. ALSO REPORTED SEVERAL 60 MPH GUSTS AROUND THAT TIME FRAME.
Dec 15, 8:42 PM CST	TSTM WND DMG	2 Wnw Coralville, IA	ESTIMATED 70 MPH WIND GUST KNOCKED DOWN A TIN SHED.
Dec 15, 8:45 PM CST	TSTM WND DMG	Coggon, IA	TREE DOWN ON HOUSE. TIME ESTIMATED BY RADAR.
Dec 15, 8:48 PM CST	TSTM WND DMG	2 Ne Robinson, IA	SHINGLE DAMAGE REPORTED AS WELL AS OTHER DAMAGE IN THE NEIGHBORHOOD.
Dec 15, 8:49 PM CST	TSTM WND DMG	Greeley, IA	HOUSE AND ROOF DAMAGE IN GREELEY AND ONEIDA.
Dec 15, 8:52 PM CST	TSTM WND GST 64	2 Ssw Williamstown, IA
Dec 15, 8:52 PM CST	TSTM WND GST 70	Iowa City Municipality, IA
Dec 15, 8:54 PM CST	TSTM WND GST 70	2 Se Iowa City, IA
Dec 15, 8:57 PM CST	TSTM WND GST 60	1 Ene Tiffin, IA
Dec 15, 9:00 PM CST	TSTM WND GST 70	4 E Iowa City, IA	POWER OUT.

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
Dec 15, 5:30 PM CST	Tornado Watch	SPC	6 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 2.1 hours before the alert went out and 91 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: 229 J/kg
Mixed-layer CIN: -358 J/kg
Mixed-layer LCL: 1061 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 433 m²/s²
0-3 km storm-relative helicity: 496 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

406 
WUUS53 KDVN 160208
SVRDVN
IAC019-055-103-113-115-183-160315-
/O.NEW.KDVN.SV.W.0112.211216T0208Z-211216T0315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
808 PM CST Wed Dec 15 2021

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Northwestern Louisa County in southeastern Iowa...
  Southeastern Buchanan County in northeastern Iowa...
  Johnson County in east central Iowa...
  Washington County in southeastern Iowa...
  Delaware County in northeastern Iowa...
  Linn County in east central Iowa...

* Until 915 PM CST.

* At 808 PM CST, severe thunderstorms were located along a line
  extending from near Hazleton to 8 miles southeast of Harper, moving
  east at 65 mph.

  HAZARD...70 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Locations impacted include...
  Cedar Rapids, Iowa City, Washington, Manchester, Columbus Junction,
  Marion, Coralville, North Liberty, Hiawatha, Mount Vernon, Robins,
  Center Point, Kalona, Lisbon, Fairfax, Solon, Tiffin, Ely, Walford
  and Wellman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for southeastern,
northeastern and east central Iowa.

This is a DANGEROUS SITUATION. These storms are producing widespread
wind damage. SEEK SHELTER NOW inside a sturdy structure and stay away 
from windows!
 
A Tornado Watch remains in effect until 1100 PM CST for southeastern,
northeastern and east central Iowa.

&&

LAT...LON 4230 9137 4134 9137 4134 9134 4116 9137
      4117 9194 4151 9194 4151 9182 4231 9183
      4263 9162 4265 9120
TIME...MOT...LOC 0208Z 274DEG 56KT 4261 9185 4130 9190 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

McClure

5 follow-up statements

126 
WWUS53 KDVN 160227
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
827 PM CST Wed Dec 15 2021

IAC019-055-103-113-115-183-160315-
/O.CON.KDVN.SV.W.0112.000000T0000Z-211216T0315Z/
Louisa IA-Buchanan IA-Johnson IA-Washington IA-Delaware IA-Linn IA-
827 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CST
FOR NORTHWESTERN LOUISA...SOUTHEASTERN BUCHANAN...JOHNSON...
WASHINGTON...DELAWARE AND LINN COUNTIES...

At 826 PM CST, severe thunderstorms were located along a line
extending from near Dundee to Ainsworth, moving east at 65 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Trained weather spotters. A trained spotter measured 70 mph
         winds in Norway. 

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Cedar Rapids, Iowa City, Washington, Manchester, Columbus Junction,
Marion, Coralville, North Liberty, Hiawatha, Mount Vernon, Robins,
Center Point, Kalona, Lisbon, Fairfax, Solon, Tiffin, Ely, Walford
and Wellman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for southeastern,
northeastern and east central Iowa.

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

&&

LAT...LON 4230 9137 4134 9137 4134 9134 4116 9137
      4117 9194 4151 9194 4151 9182 4231 9183
      4263 9162 4265 9120
TIME...MOT...LOC 0226Z 274DEG 56KT 4259 9149 4128 9155 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...70 MPH

$$

McClure

103 
WWUS53 KDVN 160230
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
830 PM CST Wed Dec 15 2021

IAC019-055-103-113-115-183-160315-
/O.CON.KDVN.SV.W.0112.000000T0000Z-211216T0315Z/
Louisa IA-Buchanan IA-Johnson IA-Washington IA-Delaware IA-Linn IA-
830 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CST
FOR NORTHWESTERN LOUISA...SOUTHEASTERN BUCHANAN...JOHNSON...
WASHINGTON...DELAWARE AND LINN COUNTIES...

At 830 PM CST, severe thunderstorms were located along a line
extending from near Edgewood to Cotter, moving east at 65 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Cedar Rapids, Iowa City, Washington, Manchester, Columbus Junction,
Marion, Coralville, North Liberty, Hiawatha, Mount Vernon, Robins,
Center Point, Kalona, Lisbon, Fairfax, Solon, Tiffin, Ely, Walford
and Wellman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for southeastern,
northeastern and east central Iowa.

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

&&

LAT...LON 4230 9137 4134 9137 4134 9134 4116 9137
      4117 9194 4151 9194 4151 9182 4231 9183
      4263 9162 4265 9120
TIME...MOT...LOC 0230Z 274DEG 56KT 4259 9142 4128 9148 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...70 MPH

$$

McClure

314 
WWUS53 KDVN 160237
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
837 PM CST Wed Dec 15 2021

IAC019-055-103-113-115-183-160315-
/O.CON.KDVN.SV.W.0112.000000T0000Z-211216T0315Z/
Louisa IA-Buchanan IA-Johnson IA-Washington IA-Delaware IA-Linn IA-
837 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CST
FOR NORTHWESTERN LOUISA...SOUTHEASTERN BUCHANAN...JOHNSON...
WASHINGTON...DELAWARE AND LINN COUNTIES...

At 836 PM CST, severe thunderstorms were located along a line
extending from Greeley to Columbus Junction, moving east at 65 mph.

HAZARD...70 mph wind gusts. A wind gust of 66 mph was measured at The
         Eastern Iowa Airport at 830 PM.  

SOURCE...Trained weather spotters.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Cedar Rapids, Iowa City, Washington, Manchester, Columbus Junction,
Marion, Coralville, North Liberty, Hiawatha, Mount Vernon, Robins,
Center Point, Kalona, Lisbon, Fairfax, Solon, Tiffin, Ely, Walford
and Wellman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for southeastern,
northeastern and east central Iowa.

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

&&

LAT...LON 4230 9137 4134 9137 4134 9134 4116 9137
      4117 9194 4151 9194 4151 9182 4231 9183
      4263 9162 4265 9120
TIME...MOT...LOC 0236Z 274DEG 56KT 4258 9130 4127 9137 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...70 MPH

$$

McClure

560 
WWUS53 KDVN 160305
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
905 PM CST Wed Dec 15 2021

IAC019-055-103-113-115-183-160315-
/O.CON.KDVN.SV.W.0112.000000T0000Z-211216T0315Z/
Louisa IA-Buchanan IA-Johnson IA-Washington IA-Delaware IA-Linn IA-
905 PM CST Wed Dec 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CST
FOR NORTHWESTERN LOUISA...SOUTHEASTERN BUCHANAN...JOHNSON...
WASHINGTON...DELAWARE AND LINN COUNTIES...

At 905 PM CST, severe thunderstorms were located along a line
extending from Sageville to Millersburg, moving east at 65 mph.

HAZARD...70 mph wind gusts.

SOURCE...Trained weather spotters.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Cedar Rapids, Iowa City, Washington, Manchester, Columbus Junction,
Marion, Coralville, North Liberty, Hiawatha, Mount Vernon, Robins,
Center Point, Kalona, Lisbon, Fairfax, Solon, Tiffin, Ely, Walford
and Wellman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for southeastern,
northeastern and east central Iowa.

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

&&

LAT...LON 4230 9137 4134 9137 4134 9134 4116 9137
      4117 9194 4151 9194 4151 9182 4231 9183
      4263 9162 4265 9120
TIME...MOT...LOC 0305Z 274DEG 56KT 4255 9071 4124 9079 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...70 MPH

$$

McClure

794 
WWUS53 KDVN 160315
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
915 PM CST Wed Dec 15 2021

IAC019-055-103-113-115-183-160324-
/O.EXP.KDVN.SV.W.0112.000000T0000Z-211216T0315Z/
Louisa IA-Buchanan IA-Johnson IA-Washington IA-Delaware IA-Linn IA-
915 PM CST Wed Dec 15 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN LOUISA...
SOUTHEASTERN BUCHANAN...JOHNSON...WASHINGTON...DELAWARE AND LINN
COUNTIES WILL EXPIRE AT 915 PM CST...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire for much of 
the area. Severe thunderstorms will continue to impact portions
of Louisa County.

A Tornado Watch remains in effect until 1100 PM CST for southeastern,
northeastern and east central Iowa.

LAT...LON 4230 9137 4134 9137 4134 9134 4116 9137
      4117 9194 4151 9194 4151 9182 4231 9183
      4263 9162 4265 9120
TIME...MOT...LOC 0314Z 274DEG 56KT 4254 9053 4123 9062 

$$

McClure

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 15, 7:17 PM CST	Severe Thunderstorm Warning Destructive damage threat	DVN	Benton, Iowa	58 min
Dec 15, 7:31 PM CST	Severe Thunderstorm Warning Considerable damage threat	DVN	Jefferson, Keokuk, Van Buren	59 min
Dec 15, 7:33 PM CST	Severe Thunderstorm Warning Considerable damage threat	DVN	Buchanan	57 min
Dec 15, 8:06 PM CST	Tornado Warning	DVN	Benton, Buchanan	20 min
Dec 15, 8:18 PM CST	Severe Thunderstorm Warning Considerable damage threat	DVN	Henry, Jefferson, Lee, Van Buren	57 min
Dec 15, 8:23 PM CST	Severe Thunderstorm Warning Considerable damage threat	DVN	Benton, Iowa	37 min
Dec 15, 8:34 PM CST	Severe Thunderstorm Warning Considerable damage threat	DVN	Jefferson, Keokuk, Van Buren	26 min
Dec 15, 8:44 PM CST	Severe Thunderstorm Warning Considerable damage threat	DVN	Delaware, Dubuque, Jones	61 min
Dec 15, 8:50 PM CST	Severe Thunderstorm Warning Considerable damage threat	DVN	Cedar, Louisa, Muscatine	55 min
Dec 15, 8:53 PM CST	Severe Thunderstorm Warning Considerable damage threat	DVN	Des Moines, Lee	67 min
Dec 15, 9:12 PM CST	Severe Thunderstorm Warning Considerable damage threat	DVN	Clinton, Dubuque, Jackson, Scott	63 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.