Alert archive / Iowa / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 114, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 27, 2021, 1:25 AM CDT for 4 counties in Iowa. It was in force for 50 min. 2 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, 1:25 AM CDT (06:25 UTC)
- Expired
- Aug 27, 2021, 2:15 AM CDT
- In force
- 50 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Storm-based polygon
- Tornado
- Possible
- Damage threat
- Considerable
- Hail
- 0.75 in
- Wind
- 70.0 mph
Counties Cherokee County, IA, Ida County, IA, Plymouth County, IA, Woodbury County, IA
The radar
The Omaha radar (KOAX), 144 km from the middle of the area, began a volume at 06:29 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 27, 1:46 AM CDT | TSTM WND DMG | 3 Wsw Cleghorn, IA | SOCIAL MEDIA REPORTS SPORADIC CORN STALKS FLATTENED. TIME ESTIMATED FROM RADAR. |
| Aug 27, 2:05 AM CDT | TSTM WND DMG | 3 W Cherokee, IA | SOCIAL MEDIA DELAYED REPORT OF LARGE TREE DAMAGE. TIME ESTIMATED FROM RADAR. |
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 26, 8:03 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 6.4 hours before the alert went out and 144 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
- 5342 J/kg
- Mixed-layer CIN
- -16 J/kg
- Mixed-layer LCL
- 1163 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 111 m²/s²
- 0-3 km storm-relative helicity
- 199 m²/s²
- Significant tornado parameter
- 3.8
- Supercell composite
- 24.0
The text
As transmitted.
939
WUUS53 KFSD 270625
SVRFSD
IAC035-093-149-193-270715-
/O.NEW.KFSD.SV.W.0114.210827T0625Z-210827T0715Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
125 AM CDT Fri Aug 27 2021
The National Weather Service in Sioux Falls has issued a
* Severe Thunderstorm Warning for...
Cherokee County in northwestern Iowa...
Eastern Woodbury County in west central Iowa...
Eastern Plymouth County in northwestern Iowa...
Ida County in west central Iowa...
* Until 215 AM CDT.
* At 125 AM CDT, severe thunderstorms were located along a line
extending from 6 miles east of Struble to near Kingsley to 7 miles
east of Salix, moving east at 40 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.
* Severe thunderstorms will be near...
Kingsley around 130 AM CDT.
Remsen around 135 AM CDT.
Pierson around 140 AM CDT.
Marcus and Correctionville around 145 AM CDT.
Other locations in the path of these severe thunderstorms include
Anthon, Washta, Quimby, Cleghorn, Holstein, Cushing, Larrabee, Battle
Creek and Galva.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4231 9616 4291 9612 4291 9539 4248 9539
4247 9532 4224 9533
TIME...MOT...LOC 0625Z 263DEG 34KT 4288 9607 4257 9604 4234 9615
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
$$
Weisser2 follow-up statements
615
WWUS53 KFSD 270638
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
138 AM CDT Fri Aug 27 2021
IAC035-093-149-193-270715-
/O.CON.KFSD.SV.W.0114.000000T0000Z-210827T0715Z/
Cherokee IA-Woodbury IA-Plymouth IA-Ida IA-
138 AM CDT Fri Aug 27 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 AM CDT
FOR CHEROKEE...EASTERN WOODBURY...EASTERN PLYMOUTH AND IDA
COUNTIES...
At 135 AM CDT, severe thunderstorms were located along a line
extending from near Remsen to Kingsley to 8 miles north of Hornick,
moving east at 40 mph.
HAZARD...70 mph wind gusts and penny size hail.
SOURCE...Radar indicated.
IMPACT...Expect considerable tree damage. Damage is likely to mobile
homes, roofs, and outbuildings.
These severe storms will be near...
Pierson around 140 AM CDT.
Correctionville around 145 AM CDT.
Holstein around 210 am CDT.
Cherokee around 210 am CDT.
Other locations in the path of these severe thunderstorms include
Marcus, Anthon, Washta, Cleghorn, Quimby, Cushing, Battle Creek,
Larrabee, Ida Grove and Aurelia.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4231 9616 4291 9612 4291 9539 4248 9539
4247 9532 4224 9533
TIME...MOT...LOC 0635Z 263DEG 34KT 4289 9597 4258 9594 4235 9605
TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH
$$
Weisser753
WWUS53 KFSD 270711
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
211 AM CDT Fri Aug 27 2021
IAC035-093-149-193-270720-
/O.EXP.KFSD.SV.W.0114.000000T0000Z-210827T0715Z/
Cherokee IA-Woodbury IA-Plymouth IA-Ida IA-
211 AM CDT Fri Aug 27 2021
...THE SEVERE THUNDERSTORM WARNING FOR CHEROKEE...EASTERN WOODBURY...
EASTERN PLYMOUTH AND IDA COUNTIES WILL EXPIRE AT 215 AM CDT...
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However gusty
winds to 55 mph and heavy rain are still possible with these
thunderstorms as they move through southeast Woodbury county,
eastern Ckerokee county and Ida county.
A Severe Thunderstorm Watch remains in effect until 300 AM CDT for
northwestern and west central Iowa.
LAT...LON 4231 9616 4291 9612 4291 9539 4248 9539
4247 9532 4224 9533
TIME...MOT...LOC 0710Z 277DEG 40KT 4286 9547 4255 9544 4229 9584
$$
WeisserThe office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 27, 12:17 AM CDT | Severe Thunderstorm Warning | FSD | Lyon, Sioux | 28 min |
| Aug 27, 12:34 AM CDT | Severe Thunderstorm Warning | FSD | Plymouth, Sioux | 41 min |
| Aug 27, 1:04 AM CDT | Tornado Warning | FSD | Sioux | 26 min |
| Aug 27, 1:09 AM CDT | Severe Thunderstorm Warning | FSD | Cherokee, Lyon, O'Brien, Osceola, Plymouth, Sioux | 51 min |
| Aug 27, 1:52 AM CDT | Severe Thunderstorm Warning | FSD | Buena Vista, Cherokee, Clay, Dickinson, O'Brien, Osceola | 68 min |
| Aug 27, 2:00 AM CDT | Severe Thunderstorm Warning | FSD | Buena Vista | 60 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.