Alert archive / Iowa / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 85, NWS Quad Cities, IA
NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 11, 2021, 5:11 PM CDT for 4 counties in Iowa. It was in force for 49 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 11, 2021, 5:11 PM CDT (22:11 UTC)
- Expired
- Aug 11, 2021, 6:00 PM CDT
- In force
- 49 min
- Issued by
- NWS Quad Cities, IA
- Area
- Storm-based polygon
- Tornado
- Possible
- Hail
- 1.5 in
- Wind
- 60.0 mph
Counties Delaware County, IA, Dubuque County, IA, Jackson County, IA, Jones County, IA
The radar
The Quad Cities radar (KDVN), 95 km from the middle of the area, began a volume at 22:13 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 11, 5:40 PM CDT | TORNADO | 2 Se Farley, IA | EMERGENCY MANAGER REPORTED A TORNADO TOUCHDOWN IN A FIELD WITH A NOTICEABLE DAMAGE PATH, DAMAGING CROPS AND ENDING IN NEARBY TIMBER. SIGNIFICANT BRANCH DAMAGE IN TIMBER. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 10.2 hours before the alert went out and 97 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.
- Mixed-layer CAPE
- 2852 J/kg
- Mixed-layer CIN
- -107 J/kg
- Mixed-layer LCL
- 1040 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 170 m²/s²
- 0-3 km storm-relative helicity
- 193 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.7
The text
As transmitted.
996
WUUS53 KDVN 112211
SVRDVN
IAC055-061-097-105-112300-
/O.NEW.KDVN.SV.W.0085.210811T2211Z-210811T2300Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
511 PM CDT Wed Aug 11 2021
The National Weather Service in the Quad Cities has issued a
* Severe Thunderstorm Warning for...
West central Jackson County in east central Iowa...
Southwestern Dubuque County in northeastern Iowa...
Northeastern Jones County in east central Iowa...
Southeastern Delaware County in northeastern Iowa...
* Until 600 PM CDT.
* At 511 PM CDT, a severe thunderstorm was located near Hopkinton, or
14 miles southeast of Manchester, moving east at 35 mph.
HAZARD...Ping pong ball size hail and 60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...People and animals outdoors will be injured. Expect hail
damage to roofs, siding, windows, and vehicles. Expect
wind damage to roofs, siding, and trees.
* This severe thunderstorm will be near...
Dyersville and Worthington around 520 PM CDT.
Cascade and Farley around 530 PM CDT.
Other locations in the path of this severe thunderstorm include
Epworth, Peosta, Centralia and Bernard.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
sturdy building.
&&
LAT...LON 4234 9132 4246 9128 4250 9074 4224 9076
TIME...MOT...LOC 2211Z 272DEG 29KT 4239 9121
TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Ervin5 follow-up statements
825
WWUS53 KDVN 112221
SVSDVN
Severe Weather Statement
National Weather Service Quad Cities IA/IL
521 PM CDT Wed Aug 11 2021
IAC055-061-097-105-112300-
/O.CON.KDVN.SV.W.0085.000000T0000Z-210811T2300Z/
Jackson IA-Dubuque IA-Jones IA-Delaware IA-
521 PM CDT Wed Aug 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM CDT
FOR WEST CENTRAL JACKSON...SOUTHWESTERN DUBUQUE...NORTHEASTERN JONES
AND SOUTHEASTERN DELAWARE COUNTIES...
At 521 PM CDT, a severe thunderstorm was located over Worthington, or
19 miles east of Manchester, moving east at 30 mph.
HAZARD...Ping pong ball size hail and 60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...People and animals outdoors will be injured. Expect hail
damage to roofs, siding, windows, and vehicles. Expect wind
damage to roofs, siding, and trees.
This severe storm will be near...
Farley around 530 PM CDT.
Other locations in the path of this severe thunderstorm include
Cascade, Epworth, Peosta and Bernard.
LAT...LON 4234 9129 4247 9114 4250 9074 4224 9076
TIME...MOT...LOC 2221Z 279DEG 28KT 4238 9111
TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Ervin696
WWUS53 KDVN 112230
SVSDVN
Severe Weather Statement
National Weather Service Quad Cities IA/IL
530 PM CDT Wed Aug 11 2021
IAC055-061-097-105-112300-
/O.CON.KDVN.SV.W.0085.000000T0000Z-210811T2300Z/
Jackson IA-Dubuque IA-Jones IA-Delaware IA-
530 PM CDT Wed Aug 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM CDT
FOR WEST CENTRAL JACKSON...SOUTHWESTERN DUBUQUE...NORTHEASTERN JONES
AND SOUTHEASTERN DELAWARE COUNTIES...
At 529 PM CDT, a severe thunderstorm was located near Cascade, or 19
miles southwest of Dubuque, moving east at 30 mph.
HAZARD...Ping pong ball size hail and 60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...People and animals outdoors will be injured. Expect hail
damage to roofs, siding, windows, and vehicles. Expect wind
damage to roofs, siding, and trees.
This severe storm will be near...
Epworth around 535 PM CDT.
Other locations in the path of this severe thunderstorm include
Peosta and Bernard.
LAT...LON 4233 9119 4247 9114 4250 9074 4224 9076
TIME...MOT...LOC 2229Z 279DEG 28KT 4237 9102
TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Ervin234
WWUS53 KDVN 112235
SVSDVN
Severe Weather Statement
National Weather Service Quad Cities IA/IL
535 PM CDT Wed Aug 11 2021
IAC055-105-112245-
/O.CAN.KDVN.SV.W.0085.000000T0000Z-210811T2300Z/
Jones IA-Delaware IA-
535 PM CDT Wed Aug 11 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN JONES AND
SOUTHEASTERN DELAWARE COUNTIES IS CANCELLED...
The severe thunderstorm which prompted the warning has moved out of
the warned area. Therefore, the warning has been cancelled.
LAT...LON 4224 9076 4228 9090 4230 9090 4230 9097
4233 9110 4246 9104 4250 9074
TIME...MOT...LOC 2235Z 279DEG 28KT 4236 9096
$$
IAC061-097-112300-
/O.CON.KDVN.SV.W.0085.000000T0000Z-210811T2300Z/
Jackson IA-Dubuque IA-
535 PM CDT Wed Aug 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM CDT
FOR WEST CENTRAL JACKSON AND SOUTHWESTERN DUBUQUE COUNTIES...
At 535 PM CDT, a severe thunderstorm was located near Cascade, or 16
miles southwest of Dubuque, moving east at 30 mph.
HAZARD...Ping pong ball size hail and 60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...People and animals outdoors will be injured. Expect hail
damage to roofs, siding, windows, and vehicles. Expect wind
damage to roofs, siding, and trees.
This severe storm will be near...
Peosta around 545 PM CDT.
Bernard around 550 PM CDT.
LAT...LON 4224 9076 4228 9090 4230 9090 4230 9097
4233 9110 4246 9104 4250 9074
TIME...MOT...LOC 2235Z 279DEG 28KT 4236 9096
TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Ervin570
WWUS53 KDVN 112247
SVSDVN
Severe Weather Statement
National Weather Service Quad Cities IA/IL
547 PM CDT Wed Aug 11 2021
IAC097-112256-
/O.CAN.KDVN.SV.W.0085.000000T0000Z-210811T2300Z/
Jackson IA-
547 PM CDT Wed Aug 11 2021
...THE SEVERE THUNDERSTORM WARNING FOR WEST CENTRAL JACKSON COUNTY IS
CANCELLED...
The severe thunderstorm which prompted the warning has moved out of
the warned area. Therefore, the warning has been cancelled.
LAT...LON 4230 9076 4230 9083 4231 9088 4233 9095
4234 9105 4244 9103 4250 9074
TIME...MOT...LOC 2246Z 266DEG 27KT 4239 9087
$$
IAC061-112300-
/O.CON.KDVN.SV.W.0085.000000T0000Z-210811T2300Z/
Dubuque IA-
547 PM CDT Wed Aug 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM CDT
FOR SOUTHWESTERN DUBUQUE COUNTY...
At 546 PM CDT, a severe thunderstorm was located near Peosta, or 11
miles southwest of Dubuque, moving east at 30 mph.
HAZARD...Ping pong ball size hail and 60 mph wind gusts. In
addition, a radar indicated tornado is possible near
Epworth.
SOURCE...Radar indicated.
IMPACT...People and animals outdoors will be injured. Expect hail
damage to roofs, siding, windows, and vehicles. Expect wind
damage to roofs, siding, and trees.
This severe storm will be near...
Centralia around 550 PM CDT.
Dubuque around 555 PM CDT.
LAT...LON 4230 9076 4230 9083 4231 9088 4233 9095
4234 9105 4244 9103 4250 9074
TIME...MOT...LOC 2246Z 266DEG 27KT 4239 9087
TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Ervin179
WWUS53 KDVN 112252
SVSDVN
Severe Weather Statement
National Weather Service Quad Cities IA/IL
552 PM CDT Wed Aug 11 2021
IAC061-112302-
/O.EXP.KDVN.SV.W.0085.000000T0000Z-210811T2300Z/
Dubuque IA-
552 PM CDT Wed Aug 11 2021
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN DUBUQUE COUNTY
WILL EXPIRE AT 600 PM CDT...
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.
To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
the Quad Cities.
LAT...LON 4230 9076 4230 9083 4231 9088 4233 9095
4234 9105 4244 9103 4250 9074
TIME...MOT...LOC 2252Z 272DEG 29KT 4239 9082
$$
ErvinThe office that day
Everything else NWS Quad Cities, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 5:38 AM CDT | Special Weather Statement | DVN | Lee | 37 min |
| Aug 11, 5:56 AM CDT | Severe Thunderstorm Warning | DVN | Des Moines, Lee | 19 min |
| Aug 11, 6:10 AM CDT | Severe Thunderstorm Warning | DVN | Des Moines, Henry, Lee | 20 min |
| Aug 11, 6:24 AM CDT | Severe Thunderstorm Warning | DVN | Des Moines | 22 min |
| Aug 11, 6:38 AM CDT | Severe Thunderstorm Warning | DVN | Des Moines, Louisa | 37 min |
| Aug 11, 6:59 AM CDT | Flash Flood Warning | DVN | Des Moines, Lee | 3 hr |
| Aug 11, 7:04 AM CDT | Special Weather Statement | DVN | Muscatine | 26 min |
| Aug 11, 8:16 AM CDT | High Wind Warning | DVN | Clinton, Des Moines, Louisa, Muscatine, Scott | 104 min |
| Aug 11, 9:46 AM CDT | Areal Flood Warning | DVN | Des Moines, Lee | 3 hr |
| Aug 11, 10:24 AM CDT | Special Weather Statement | DVN | Lee | 21 min |
| Aug 11, 3:36 PM CDT | Special Weather Statement | DVN | Washington | 24 min |
| Aug 11, 4:26 PM CDT | Severe Thunderstorm Warning | DVN | Delaware, Dubuque | 49 min |
| Aug 11, 5:38 PM CDT | Tornado Warning | DVN | Dubuque | 13 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.