Alert archive / Iowa / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 144, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 28, 2021, 9:13 PM CDT for Jackson County, Nobles County, Rock County, Minnesota; 5 counties in Iowa; Lincoln County, South Dakota. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Aug 28, 2021, 9:13 PM CDT (02:13 UTC)
- Expired
- Aug 28, 2021, 10:00 PM CDT
- In force
- 47 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Dickinson County, IA, Lyon County, IA, O'Brien County, IA, Osceola County, IA, Sioux County, IA, Jackson County, MN, Nobles County, MN, Rock County, MN, Lincoln County, SD
The radar
The Sioux Falls radar (KFSD), 73 km from the middle of the area, began a volume at 02:16 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.
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 28, 3:57 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Minneapolis, MN (KMPX), launched 00:00Z, 2.2 hours before the alert went out and 236 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
- 1990 J/kg
- Mixed-layer CIN
- -120 J/kg
- Mixed-layer LCL
- 977 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 252 m²/s²
- 0-3 km storm-relative helicity
- 227 m²/s²
- Significant tornado parameter
- 1.0
- Supercell composite
- 5.0
The text
As transmitted.
733
WUUS53 KFSD 290213
SVRFSD
IAC059-119-141-143-167-MNC063-105-133-SDC083-290300-
/O.NEW.KFSD.SV.W.0144.210829T0213Z-210829T0300Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
913 PM CDT Sat Aug 28 2021
The National Weather Service in Sioux Falls has issued a
* Severe Thunderstorm Warning for...
Lyon County in northwestern Iowa...
Osceola County in northwestern Iowa...
Northwestern Dickinson County in northwestern Iowa...
Northern Sioux County in northwestern Iowa...
Northwestern O'Brien County in northwestern Iowa...
Eastern Rock County in southwestern Minnesota...
Jackson County in southwestern Minnesota...
Nobles County in southwestern Minnesota...
Southeastern Lincoln County in southeastern South Dakota...
* Until 1000 PM CDT.
* At 912 PM CDT, severe thunderstorms were located along a line
extending from near Wilmont to near Adrian to Rock Rapids to near
Alcester, moving east at 65 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
* Severe thunderstorms will be near...
Adrian, Ellsworth and Rushmore around 920 PM CDT.
Little Rock around 925 PM CDT.
Worthington and Rock Valley around 930 PM CDT.
Sioux Center, Doon and Brewster around 935 PM CDT.
Hull around 940 PM CDT.
George, Boyden, Heron Lake and Round Lake around 945 PM CDT.
Sheldon and Matlock around 950 PM CDT.
Ashton and Kilen Woods State Park around 955 PM CDT.
Other locations impacted by these severe thunderstorms include
Kenneth, Kinbrae, Wilder, Dundee, Steen, Magnolia, Okabena and
Bigelow.
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 4339 9521 4310 9573 4309 9677 4345 9643
4361 9624 4385 9615 4385 9499
TIME...MOT...LOC 0212Z 253DEG 54KT 4381 9580 4359 9594 4343 9614 4311
9664
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SG3 follow-up statements
528
WWUS53 KFSD 290221
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
921 PM CDT Sat Aug 28 2021
IAC059-119-141-143-167-MNC063-105-133-SDC083-290300-
/O.CON.KFSD.SV.W.0144.000000T0000Z-210829T0300Z/
Lyon IA-Osceola IA-Dickinson IA-Sioux IA-O'Brien IA-Rock MN-
Jackson MN-Nobles MN-Lincoln SD-
921 PM CDT Sat Aug 28 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 PM CDT
FOR LYON...OSCEOLA...NORTHWESTERN DICKINSON...NORTHERN SIOUX...
NORTHWESTERN O'BRIEN...EASTERN ROCK...JACKSON...NOBLES AND
SOUTHEASTERN LINCOLN COUNTIES...
At 920 PM CDT, severe thunderstorms were located along a line
extending from near Fulda to Rushmore to near Rock Rapids to near
Hudson, moving east at 60 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
These severe storms will be near...
Rushmore around 925 PM CDT.
Worthington and Little Rock around 930 PM CDT.
Ashton and Round Lake around 935 PM CDT.
Sioux Center, Sibley, Hull, Heron Lake and Brewster around 940 PM
CDT.
Boyden and Melvin around 945 PM CDT.
Ocheyedan, Matlock and Kilen Woods State Park around 950 PM CDT.
Sheldon, Lakefield and Harris around 955 PM CDT.
Lake Park and Archer around 1000 PM CDT.
Other locations impacted by these severe thunderstorms include
Kenneth, Kinbrae, Wilder, Dundee, Steen, Magnolia, Okabena and
Bigelow.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4339 9521 4310 9573 4309 9674 4344 9642
4361 9624 4385 9615 4385 9499
TIME...MOT...LOC 0220Z 272DEG 51KT 4384 9566 4362 9580 4341 9610 4314
9650
TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SG487
WWUS53 KFSD 290245
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
945 PM CDT Sat Aug 28 2021
MNC133-SDC083-290255-
/O.CAN.KFSD.SV.W.0144.000000T0000Z-210829T0300Z/
Rock MN-Lincoln SD-
945 PM CDT Sat Aug 28 2021
...THE SEVERE THUNDERSTORM WARNING FOR EASTERN ROCK AND SOUTHEASTERN
LINCOLN COUNTIES IS CANCELLED...
The storms which prompted the warning have moved out of the warned
area. Therefore, the warning has been cancelled.
A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
northwestern Iowa...and southwestern Minnesota.
LAT...LON 4339 9521 4310 9573 4309 9642 4350 9606
4385 9592 4385 9499
TIME...MOT...LOC 0245Z 258DEG 40KT 4383 9535 4365 9552 4338 9587 4313
9620
$$
IAC059-119-141-143-167-MNC063-105-290300-
/O.CON.KFSD.SV.W.0144.000000T0000Z-210829T0300Z/
Lyon IA-Osceola IA-Dickinson IA-Sioux IA-O'Brien IA-Jackson MN-
Nobles MN-
945 PM CDT Sat Aug 28 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 PM CDT
FOR EASTERN LYON...OSCEOLA...NORTHWESTERN DICKINSON...NORTHERN
SIOUX...NORTHWESTERN O'BRIEN...JACKSON AND NOBLES COUNTIES...
At 945 PM CDT, severe thunderstorms were located along a line
extending from near Heron Lake to near Worthington to near Little
Rock to near Sioux Center, moving east at 45 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
These severe storms will be near...
Worthington, Heron Lake and Brewster around 950 PM CDT.
Matlock around 1005 PM CDT.
Sheldon, Lakefield and Ocheyedan around 1010 PM CDT.
Round Lake, Harris, Archer and Kilen Woods State Park around 1015
PM CDT.
Sanborn and Lake Park around 1020 PM CDT.
Melvin around 1025 PM CDT.
Other locations impacted by these severe thunderstorms include
Kinbrae, Wilder, Dundee, Okabena and Bigelow.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4339 9521 4310 9573 4309 9642 4350 9606
4385 9592 4385 9499
TIME...MOT...LOC 0245Z 258DEG 40KT 4383 9535 4365 9552 4338 9587 4313
9620
TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
SG126
WWUS53 KFSD 290255
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
955 PM CDT Sat Aug 28 2021
IAC059-119-141-143-167-MNC063-105-290305-
/O.EXP.KFSD.SV.W.0144.000000T0000Z-210829T0300Z/
Lyon IA-Osceola IA-Dickinson IA-Sioux IA-O'Brien IA-Jackson MN-
Nobles MN-
955 PM CDT Sat Aug 28 2021
...THE SEVERE THUNDERSTORM WARNING FOR EASTERN LYON...OSCEOLA...
NORTHWESTERN DICKINSON...NORTHERN SIOUX...NORTHWESTERN O'BRIEN...
JACKSON AND NOBLES COUNTIES WILL EXPIRE AT 1000 PM 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 50 miles per hour and heavy rain are still possible with
these thunderstorms.
A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
northwestern Iowa...and southwestern Minnesota.
LAT...LON 4339 9521 4310 9573 4309 9642 4350 9606
4385 9592 4385 9499
TIME...MOT...LOC 0255Z 253DEG 54KT 4387 9517 4369 9535 4342 9570 4317
9603
$$
SGThe office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 28, 7:00 PM CDT | Severe Thunderstorm Warning | FSD | Lincoln, Lyon, Murray, Pipestone | 45 min |
| Aug 28, 7:23 PM CDT | Severe Thunderstorm Warning | FSD | Rock | 52 min |
| Aug 28, 7:34 PM CDT | Severe Thunderstorm Warning | FSD | Lyon, Murray, Pipestone | 56 min |
| Aug 28, 7:48 PM CDT | Severe Thunderstorm Warning | FSD | Rock | 31 min |
| Aug 28, 8:03 PM CDT | Flash Flood Warning | FSD | Murray, Pipestone | 6 hr |
| Aug 28, 8:06 PM CDT | Severe Thunderstorm Warning | FSD | Nobles, Rock | 54 min |
| Aug 28, 8:17 PM CDT | Severe Thunderstorm Warning | FSD | Cottonwood, Lyon, Murray | 58 min |
| Aug 28, 8:52 PM CDT | Severe Thunderstorm Warning | FSD | Murray, Nobles, Rock | 23 min |
| Aug 28, 9:29 PM CDT | Flash Flood Warning | FSD | Murray, Nobles, Pipestone, Rock | 3 hr |
| Aug 28, 10:04 PM CDT | Flash Flood Warning | FSD | Cottonwood, Jackson, Murray, Nobles | 4 hr |
| Aug 28, 10:24 PM CDT | Flash Flood Warning | FSD | Cottonwood, Jackson | 5 hr |
| Aug 28, 7:25 PM CDT | Severe Thunderstorm Warning | FSD | Hanson, Lake, McCook, Miner, Minnehaha, Moody | 50 min |
| Aug 28, 7:27 PM CDT | Severe Thunderstorm Warning | FSD | Bon Homme, Hutchinson, Turner, Yankton | 48 min |
| Aug 28, 7:50 PM CDT | Severe Thunderstorm Warning | FSD | Bon Homme, Clay, Hutchinson, Lincoln, Turner, Yankton | 40 min |
| Aug 28, 9:20 PM CDT | Flash Flood Warning | FSD | Lincoln, Minnehaha | 85 min |
| Aug 28, 10:36 PM CDT | Flash Flood Warning | FSD | Lincoln, Minnehaha | 114 min |
| Aug 28, 11:46 PM CDT | River Flood Warning | FSD | Lincoln, Minnehaha | 8 hr |
| Aug 29, 7:44 AM CDT | River Flood Warning | FSD | Lincoln | 15 hr |
Nearby
Severe Thunderstorm Warnings in Iowa, 2021Severe Thunderstorm Warnings in Minnesota, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.