Alert archive / Iowa / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 111, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 27, 2021, 12:17 AM CDT for Lincoln County, South Dakota; Lyon County, Sioux County, Iowa. It was in force for 28 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 27, 2021, 12:17 AM CDT (05:17 UTC)
- Expired
- Aug 27, 2021, 12:45 AM CDT
- In force
- 28 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Lyon County, IA, Sioux County, IA, Lincoln County, SD
The radar
The Sioux Falls radar (KFSD), 51 km from the middle of the area, began a volume at 05:18 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, 12:30 AM CDT | HAIL 1.75 | 2 Ese Inwood, IA | SPOTTER LOCATED 2 MILES ESE OF INWOOD REPORTED PEA HAIL WITH A FEW GOLF BALL SIZED AT THEIR LOCATION. |
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, 5.3 hours before the alert went out and 218 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.
774
WUUS53 KFSD 270517
SVRFSD
IAC119-167-SDC083-270545-
/O.NEW.KFSD.SV.W.0111.210827T0517Z-210827T0545Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
1217 AM CDT Fri Aug 27 2021
The National Weather Service in Sioux Falls has issued a
* Severe Thunderstorm Warning for...
Southeastern Lyon County in northwestern Iowa...
Northwestern Sioux County in northwestern Iowa...
East central Lincoln County in southeastern South Dakota...
* Until 1245 AM CDT.
* At 1216 AM CDT, a pair of severe thunderstorms were located near
Fairview, or 10 miles southeast of Canton, moving northeast at 50
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.
* This severe thunderstorm will be near...
Rock Valley around 1220 AM CDT.
Alvord around 1225 AM CDT.
Doon around 1230 AM CDT.
Rock Rapids around 1235 AM CDT.
Other locations in the path of these severe thunderstorms include
George.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4327 9663 4349 9617 4332 9586 4327 9587
4308 9640
TIME...MOT...LOC 0516Z 241DEG 42KT 4323 9640
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SG1 follow-up statement
070
WWUS53 KFSD 270528
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
1228 AM CDT Fri Aug 27 2021
IAC119-167-SDC083-270545-
/O.CON.KFSD.SV.W.0111.000000T0000Z-210827T0545Z/
Lyon IA-Sioux IA-Lincoln SD-
1228 AM CDT Fri Aug 27 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1245 AM CDT
FOR SOUTHEASTERN LYON...NORTHWESTERN SIOUX AND EAST CENTRAL LINCOLN
COUNTIES...
At 1227 AM CDT, a severe thunderstorm was located near Alvord, or 12
miles east of Canton, moving northeast at 35 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage to
roofs, siding, and trees.
This severe storm will be near...
Alvord around 1235 AM CDT.
Other locations in the path of this severe thunderstorm include Rock
Rapids.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4327 9663 4349 9617 4332 9586 4327 9587
4318 9620
TIME...MOT...LOC 0527Z 218DEG 31KT 4327 9633
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SGThe office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 26, 11:05 PM CDT | Severe Thunderstorm Warning | FSD | Hutchinson, Turner, Yankton | 25 min |
| Aug 27, 12:08 AM CDT | Severe Thunderstorm Warning | FSD | Clay, Lincoln, Turner, Union | 37 min |
| Aug 27, 12:34 AM CDT | Severe Thunderstorm Warning | FSD | Lincoln, Union | 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, 1:25 AM CDT | Severe Thunderstorm Warning | FSD | Cherokee, Ida, Plymouth, Woodbury | 50 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, 2021Severe Thunderstorm Warnings in South Dakota, 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.