Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 26, NWS Sioux Falls, SD

June 16, 2021Buena Vista County, Cherokee County, Ida County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jun 16, 2021, 9:00 PM CDT for Buena Vista County, Cherokee County, Ida County, Iowa. It was in force for 45 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: Jun 16, 2021, 9:00 PM CDT (02:00 UTC)
Expired: Jun 16, 2021, 9:45 PM CDT
In force: 45 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Hail: 1.75 in
Wind: 60.0 mph

Counties Buena Vista County, IA, Cherokee County, IA, Ida County, IA

The radar

The Omaha radar (KOAX), 149 km from the middle of the area, began a volume at 02:00 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
Jun 16, 9:02 PM CDT	HAIL 0.88	3 S Alta, IA	LOTS OF DIME TO NICKEL SIZED HAIL. ABOUT 5 MINUTES OF WIND GUSTS TO AROUND 50 MPH.
Jun 16, 9:05 PM CDT	HAIL 1	4 Sse Alta, IA	MOSTLY DIME, BUT A FEW QUARTER SIZED HAIL STONES. ALSO ABOUT 40 TO 50 MPH WIND GUSTS.
Jun 16, 9:34 PM CDT	TSTM WND DMG	Ida Grove, IA	POWER LINES AND TREE BRANCHES DOWN ACROSS PARTS OF TOWN.
Jun 16, 9:52 PM CDT	HAIL 0.75	5 N Ida Grove, IA	REPORT FROM MPING.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 2.0 hours before the alert went out and 149 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 2997 J/kg
Mixed-layer CIN: -144 J/kg
Mixed-layer LCL: 1946 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 120 m²/s²
0-3 km storm-relative helicity: 435 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 27.9

Open this sounding in Storm Lab

The text

As transmitted.

268 
WUUS53 KFSD 170200
SVRFSD
IAC021-035-093-170245-
/O.NEW.KFSD.SV.W.0026.210617T0200Z-210617T0245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
900 PM CDT Wed Jun 16 2021

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Southeastern Cherokee County in northwestern Iowa...
  Southwestern Buena Vista County in northwestern Iowa...
  Eastern Ida County in west central Iowa...

* Until 945 PM CDT.

* At 859 PM CDT, a severe thunderstorm was located near Alta, or 8
  miles west of Storm Lake, moving south at 55 mph.

  HAZARD...Golf ball size hail and 60 mph wind gusts.

  SOURCE...Trained weather spotters. At 8:43 pm, golf ball sized 
           hail and wind gusts to 60 mph were reported northeast of 
           Aurelia, Iowa. Have also received reports of weak 
           rotation with this storm.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           wind damage to roofs, siding, and trees.

* This severe thunderstorm will be near...
  Galva around 910 PM CDT.
  Arthur around 920 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4222 9554 4263 9556 4267 9527 4256 9522
      4256 9539 4248 9539 4247 9532 4222 9533
TIME...MOT...LOC 0159Z 342DEG 48KT 4265 9537 

HAIL...1.75IN
WIND...60MPH
 
$$

APT

2 follow-up statements

311 
WWUS53 KFSD 170226
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
926 PM CDT Wed Jun 16 2021

IAC021-035-170235-
/O.CAN.KFSD.SV.W.0026.000000T0000Z-210617T0245Z/
Cherokee IA-Buena Vista IA-
926 PM CDT Wed Jun 16 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CHEROKEE AND
SOUTHWESTERN BUENA VISTA COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4222 9554 4256 9556 4256 9539 4247 9538
      4247 9532 4222 9533
TIME...MOT...LOC 0225Z 342DEG 48KT 4231 9522 

$$

IAC093-170245-
/O.CON.KFSD.SV.W.0026.000000T0000Z-210617T0245Z/
Ida IA-
926 PM CDT Wed Jun 16 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM CDT
FOR EASTERN IDA COUNTY...

At 925 PM CDT, a severe thunderstorm was located over Odebolt, or 13
miles east of Ida Grove, moving south at 55 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Trained weather spotters. At 9:05 pm, quarter sized hail 
         was reported 4 south-southeast of Alta, Iowa.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe thunderstorm will remain over mainly rural areas of
eastern Ida County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4222 9554 4256 9556 4256 9539 4247 9538
      4247 9532 4222 9533
TIME...MOT...LOC 0225Z 342DEG 48KT 4231 9522 

HAIL...1.00IN
WIND...60MPH
 
$$

APT

699 
WWUS53 KFSD 170245
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
945 PM CDT Wed Jun 16 2021

IAC093-170254-
/O.EXP.KFSD.SV.W.0026.000000T0000Z-210617T0245Z/
Ida IA-
945 PM CDT Wed Jun 16 2021

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN IDA COUNTY WILL EXPIRE
AT 945 PM CDT...
    
The severe thunderstorm which prompted the warning has weakened. 
Therefore, the warning will be allowed to expire.  However, hail is 
still possible with this thunderstorm to the size of dimes and 
nickels.

LAT...LON 4222 9554 4256 9556 4256 9539 4247 9538
      4247 9532 4222 9533
TIME...MOT...LOC 0244Z 342DEG 48KT 4207 9512 

$$

APT

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 16, 8:38 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista, Cherokee, Clay, O'Brien	37 min
Jun 16, 9:47 PM CDT	Severe Thunderstorm Warning	FSD	Ida	28 min
Jun 16, 10:04 PM CDT	Severe Thunderstorm Warning	FSD	Ida	9 min
Jun 17, 3:00 AM CDT	Heat Advisory	FSD	Buena Vista, Cherokee, Ida, Woodbury	16 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2021 Every 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.