Alert archive / Iowa / Tornado Warnings in 2021
Tornado Warning 24, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this tornado warning at Dec 15, 2021, 5:08 PM CST for Buena Vista County, Cherokee County, Clay County, Iowa. It was in force for 37 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
- Dec 15, 2021, 5:08 PM CST (23:08 UTC)
- Expired
- Dec 15, 2021, 5:45 PM CST
- In force
- 37 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Storm-based polygon
- Tornado
- Radar indicated
- Hail
- 0.75 in
Counties Buena Vista County, IA, Cherokee County, IA, Clay County, IA
The radar
The Sioux Falls radar (KFSD), 159 km from the middle of the area, began a volume at 23:08 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 |
|---|---|---|---|
| Dec 15, 5:10 PM CST | TSTM WND GST 51 | 4 Wsw Lakeside, IA | 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 |
|---|---|---|---|
| Dec 15, 1:23 PM CST | Tornado Watch | SPC | 7 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 12:00Z, 11.1 hours before the alert went out and 187 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2165 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 346 m²/s²
- 0-3 km storm-relative helicity
- 384 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
174
WFUS53 KFSD 152308
TORFSD
IAC021-035-041-152345-
/O.NEW.KFSD.TO.W.0024.211215T2308Z-211215T2345Z/
BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Sioux Falls SD
508 PM CST Wed Dec 15 2021
The National Weather Service in Sioux Falls has issued a
* Tornado Warning for...
East central Cherokee County in northwestern Iowa...
Buena Vista County in northwestern Iowa...
Southeastern Clay County in northwestern Iowa...
* Until 545 PM CST.
* At 508 PM CST, severe thunderstorms capable of producing both
tornadoes and extensive straight line wind damage were located over
Storm Lake, moving northeast at 80 mph.
HAZARD...Tornado.
SOURCE...Radar indicated rotation.
IMPACT...Flying debris will be dangerous to those caught without
shelter. Mobile homes will be damaged or destroyed.
Damage to roofs, windows, and vehicles will occur. Tree
damage is likely.
* These dangerous storms will be near...
Sioux Rapids and Albert City around 520 PM CST.
Marathon and Webb around 525 PM CST.
Other locations impacted by this tornadic thunderstorm include
Gillett Grove and Rembrandt.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.
This cluster of thunderstorms is capable of producing tornadoes and
widespread significant wind damage. Do not wait to see or hear the
tornado. For your protection move to an interior room on the lowest
floor of a building.
&&
LAT...LON 4256 9509 4256 9536 4260 9541 4267 9541
4313 9509 4310 9491 4272 9492
TIME...MOT...LOC 2308Z 218DEG 68KT 4265 9525
TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
$$
SG2 follow-up statements
984
WWUS53 KFSD 152330
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
530 PM CST Wed Dec 15 2021
IAC021-035-152339-
/O.CAN.KFSD.TO.W.0024.000000T0000Z-211215T2345Z/
Cherokee IA-Buena Vista IA-
530 PM CST Wed Dec 15 2021
...THE TORNADO WARNING FOR EAST CENTRAL CHEROKEE AND BUENA VISTA
COUNTIES IS CANCELLED...
The tornadic thunderstorm which prompted the warning has moved out
of the warned area. Therefore, the warning has been cancelled.
However, a Severe Thunderstorm Warning remains in effect.
A Tornado Watch remains in effect until 800 PM CST for northwestern
Iowa.
LAT...LON 4291 9492 4291 9500 4297 9520 4313 9509
4310 9493 4310 9491 4292 9491
TIME...MOT...LOC 2329Z 211DEG 67KT 4301 9502
$$
IAC041-152345-
/O.CON.KFSD.TO.W.0024.000000T0000Z-211215T2345Z/
Clay IA-
530 PM CST Wed Dec 15 2021
...A TORNADO WARNING REMAINS IN EFFECT UNTIL 545 PM CST FOR
SOUTHEASTERN CLAY COUNTY...
At 529 PM CST, a severe squall line capable of producing both
tornadoes and extensive straight line wind damage was located near
Webb, or 11 miles southeast of Spencer In Clay County, moving
northeast at 75 mph.
HAZARD...Tornado.
SOURCE...Radar indicated rotation.
IMPACT...Flying debris will be dangerous to those caught without
shelter. Mobile homes will be damaged or destroyed. Damage
to roofs, windows, and vehicles will occur. Tree damage is
likely.
This tornadic thunderstorm will remain over mainly rural areas of
southeastern Clay County, including the following locations...
Gillett Grove.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.
This cluster of thunderstorms is capable of producing tornadoes and
widespread significant wind damage. Do not wait to see or hear the
tornado. For your protection move to an interior room on the lowest
floor of a building.
&&
LAT...LON 4291 9492 4291 9500 4297 9520 4313 9509
4310 9493 4310 9491 4292 9491
TIME...MOT...LOC 2329Z 211DEG 67KT 4301 9502
TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
$$
SG996
WWUS53 KFSD 152342
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
542 PM CST Wed Dec 15 2021
IAC041-152352-
/O.EXP.KFSD.TO.W.0024.000000T0000Z-211215T2345Z/
Clay IA-
542 PM CST Wed Dec 15 2021
...THE TORNADO WARNING FOR SOUTHEASTERN CLAY COUNTY WILL EXPIRE AT
545 PM CST...
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire. However gusty winds are still possible with
this thunderstorm.
A Tornado Watch remains in effect until 800 PM CST for northwestern
Iowa.
LAT...LON 4291 9492 4291 9500 4297 9520 4313 9509
4310 9493 4310 9491 4292 9491
TIME...MOT...LOC 2342Z 218DEG 68KT 4318 9484
$$
SGThe office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 15, 2:56 AM CST | Dense Fog Advisory | FSD | Buena Vista, Cherokee, Clay, Dickinson, Ida, Lyon and 5 more | 6 hr |
| Dec 15, 3:23 PM CST | Severe Thunderstorm Warning | FSD | Plymouth, Woodbury | 67 min |
| Dec 15, 4:00 PM CST | Tornado Warning | FSD | Woodbury | 45 min |
| Dec 15, 4:05 PM CST | Severe Thunderstorm Warning | FSD | Buena Vista, Cherokee, Ida, Plymouth, Woodbury | 55 min |
| Dec 15, 4:17 PM CST | Tornado Warning | FSD | Plymouth, Woodbury | 28 min |
| Dec 15, 4:26 PM CST | Severe Thunderstorm Warning | FSD | Plymouth, Woodbury | 34 min |
| Dec 15, 4:31 PM CST | Tornado Warning | FSD | Ida, Plymouth, Woodbury | 29 min |
| Dec 15, 4:32 PM CST | Tornado Warning | FSD | Plymouth, Woodbury | 28 min |
| Dec 15, 4:42 PM CST | Tornado Warning | FSD | Buena Vista, Cherokee, Clay, Ida, O'Brien, Plymouth and 1 more | 33 min |
| Dec 15, 4:51 PM CST | Severe Thunderstorm Warning | FSD | O'Brien, Sioux | 39 min |
| Dec 15, 4:56 PM CST | Severe Thunderstorm Warning | FSD | Buena Vista, Cherokee, Clay, Ida | 46 min |
| Dec 15, 5:15 PM CST | Tornado Warning | FSD | Buena Vista, Cherokee, Clay, O'Brien | 30 min |
| Dec 15, 5:29 PM CST | Severe Thunderstorm Warning | FSD | Dickinson | 46 min |
Nearby
Tornado Warnings in Iowa, 2021Every tornado warning in 2021Tornadoes 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.