Alert archive / Iowa / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 104, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Aug 27, 2021, 4:23 PM CDT for Cerro Gordo County, Hancock County, Iowa. It was in force for 52 min. 4 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 27, 2021, 4:23 PM CDT (21:23 UTC)
- Expired
- Aug 27, 2021, 5:15 PM CDT
- In force
- 52 min
- Issued by
- NWS Des Moines, IA
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Cerro Gordo County, IA, Hancock County, IA
The radar
The Des Moines radar (KDMX), 145 km from the middle of the area, began a volume at 21:26 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 27, 4:45 PM CDT | FUNNEL CLOUD | 5 Ene Klemme, IA | TIME AND LOCATION ESTIMATED BY RADAR. REPORT VIA SOCIAL MEDIA. |
| Aug 27, 4:52 PM CDT | TSTM WND DMG | 2 Ese Ventura, IA | DELAYED REPORT: SOME TREE DAMAGE REPORTED AROUND THE CLEAR LAKE AREA. POWER OUTAGES ALSO REPORTED. TIME ESTIMATED VIA RADAR. |
| Aug 27, 5:07 PM CDT | TORNADO | 5 S Clear Lake, IA | TRAINED SPOTTER RELAYED REPORT TO EM OF BRIEF TORNADO TOUCH DOWN WEST OF BURCHINAL. TIME ESIMATED VIA RADAR. |
| Aug 27, 5:15 PM CDT | TORNADO | 5 Sse Clear Lake, IA | TRAINED SPOTTER RELAYED REPORT TO COUNTY LAW ENFORCEMENT OF BRIEF TORNADO ON THE GROUND SOUTHEAST OF CLEAR LAKE AND SOUTH OF MASON CITY. UNCLEAR OF DAMAGE AT THIS TIME. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Minneapolis, MN (KMPX), launched 12:00Z, 9.4 hours before the alert went out and 203 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
- 487 J/kg
- Mixed-layer CIN
- -63 J/kg
- Mixed-layer LCL
- 644 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- -9 m²/s²
- 0-3 km storm-relative helicity
- -16 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
855
WUUS53 KDMX 272123
SVRDMX
IAC033-081-272215-
/O.NEW.KDMX.SV.W.0104.210827T2123Z-210827T2215Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Des Moines IA
423 PM CDT Fri Aug 27 2021
The National Weather Service in Des Moines has issued a
* Severe Thunderstorm Warning for...
Southeastern Hancock County in north central Iowa...
Northwestern Cerro Gordo County in north central Iowa...
* Until 515 PM CDT.
* At 422 PM CDT, a severe thunderstorm was located 7 miles south of
Garner, moving northeast at 40 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...
Clear Lake and Mason City Municipal Airport.
This includes Interstate 35 between mile markers 185 and 197.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4291 9364 4301 9376 4325 9340 4306 9318
TIME...MOT...LOC 2122Z 230DEG 33KT 4300 9361
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
REV2 follow-up statements
289
WWUS53 KDMX 272142
SVSDMX
Severe Weather Statement
National Weather Service Des Moines IA
442 PM CDT Fri Aug 27 2021
IAC033-081-272215-
/O.CON.KDMX.SV.W.0104.000000T0000Z-210827T2215Z/
Hancock IA-Cerro Gordo IA-
442 PM CDT Fri Aug 27 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM CDT
FOR EAST CENTRAL HANCOCK AND NORTHWESTERN CERRO GORDO COUNTIES...
At 441 PM CDT, a severe thunderstorm was located near Clear Lake, or
near Garner, moving northeast at 30 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage to
roofs, siding, and trees.
Locations impacted include...
Garner, Mason City Municipal Airport, Clear Lake, Ventura, Klemme,
Burchinal, Clear Lake State Park and McIntosh Woods State Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4295 9353 4305 9369 4325 9340 4306 9318
TIME...MOT...LOC 2141Z 231DEG 27KT 4305 9349
TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
REV746
WWUS53 KDMX 272208
SVSDMX
Severe Weather Statement
National Weather Service Des Moines IA
508 PM CDT Fri Aug 27 2021
IAC081-272217-
/O.CAN.KDMX.SV.W.0104.000000T0000Z-210827T2215Z/
Hancock IA-
508 PM CDT Fri Aug 27 2021
...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL HANCOCK 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 4298 9347 4313 9349 4319 9334 4306 9318
TIME...MOT...LOC 2207Z 230DEG 33KT 4321 9324
$$
IAC033-272215-
/O.CON.KDMX.SV.W.0104.000000T0000Z-210827T2215Z/
Cerro Gordo IA-
508 PM CDT Fri Aug 27 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM CDT
FOR NORTHWESTERN CERRO GORDO COUNTY...
At 507 PM CDT, a severe thunderstorm was located near Mason City,
moving northeast at 40 mph. A tornado warning remains in effect for
the area.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage to
roofs, siding, and trees.
Locations impacted include...
Clear Lake, Mason City Municipal Airport, Ventura, Burchinal, Clear
Lake State Park and McIntosh Woods State Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4298 9347 4313 9349 4319 9334 4306 9318
TIME...MOT...LOC 2207Z 230DEG 33KT 4321 9324
TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
REVThe office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 26, 7:02 PM CDT | Severe Thunderstorm Warning | DMX | Audubon, Carroll | 28 min |
| Aug 26, 8:35 PM CDT | Special Weather Statement | DMX | Poweshiek | 40 min |
| Aug 26, 8:47 PM CDT | Severe Thunderstorm Warning | DMX | Mahaska, Poweshiek | 58 min |
| Aug 26, 9:46 PM CDT | Special Weather Statement | DMX | Mahaska | 44 min |
| Aug 26, 10:26 PM CDT | Special Weather Statement | DMX | Mahaska | 34 min |
| Aug 26, 10:30 PM CDT | Severe Thunderstorm Warning | DMX | Emmet, Palo Alto | 45 min |
| Aug 26, 10:52 PM CDT | Special Weather Statement | DMX | Wapello | 38 min |
| Aug 26, 11:42 PM CDT | Severe Thunderstorm Warning | DMX | Emmet, Palo Alto | 33 min |
| Aug 27, 12:13 AM CDT | Special Weather Statement | DMX | Emmet | 32 min |
| Aug 27, 2:08 PM CDT | Special Weather Statement | DMX | Hancock | 37 min |
| Aug 27, 2:59 PM CDT | Special Weather Statement | DMX | Cerro Gordo | 16 min |
| Aug 27, 4:48 PM CDT | Tornado Warning | DMX | Cerro Gordo, Hancock | 57 min |
| Aug 27, 4:58 PM CDT | Severe Thunderstorm Warning | DMX | Cerro Gordo, Franklin, Hancock | 32 min |
| Aug 27, 5:23 PM CDT | Tornado Warning | DMX | Cerro Gordo | 37 min |
| Aug 27, 5:25 PM CDT | Tornado Warning | DMX | Cerro Gordo | 35 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.