Alert archive / Iowa / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 8, NWS Sioux Falls, SD

April 15, 2017Ida County, Woodbury County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Apr 15, 2017, 8:52 PM CDT for Ida County, Woodbury County, Iowa. It was in force for 24 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: Apr 15, 2017, 8:52 PM CDT (01:52 UTC)
Expired: Apr 15, 2017, 9:16 PM CDT
In force: 24 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Ida County, IA, Woodbury County, IA

The radar

The Omaha radar (KOAX), 126 km from the middle of the area, began a volume at 01:56 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
Apr 15, 9:23 PM CDT	HAIL 0.88	1 E Anthon, IA	HAIL WAS GETTING SMALLER AND WETTER AS THE STORM APPROACHED ANTHON, BUT SOME STONES WERE AS BIG AS NICKELS.

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, 1.9 hours before the alert went out and 126 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: 1034 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 1322 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: -9 m²/s²
0-3 km storm-relative helicity: 76 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.8

Open this sounding in Storm Lab

The text

As transmitted.

999 
WUUS53 KFSD 160152
SVRFSD
IAC093-193-160245-
/O.NEW.KFSD.SV.W.0008.170416T0152Z-170416T0245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
852 PM CDT SAT APR 15 2017

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Eastern Woodbury County in west central Iowa...
  Southern Ida County in west central Iowa...

* Until 945 PM CDT

* At 852 PM CDT, a severe thunderstorm was located near Anthon, or 23
  miles west of Ida Grove, moving southeast at 30 mph.

  HAZARD...Quarter size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Damage to vehicles is expected. 

* This severe thunderstorm will be near, 
  Correctionville around 900 PM CDT. 
  Danbury around 920 PM CDT. 
  Battle Creek around 925 PM CDT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4242 9602 4252 9590 4232 9532 4221 9532
      4221 9575
TIME...MOT...LOC 0152Z 306DEG 27KT 4243 9591 

HAIL...1.00IN
WIND...<50MPH
 
$$

Hanko

2 follow-up statements

837 
WWUS53 KFSD 160208
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
908 PM CDT SAT APR 15 2017

IAC093-193-160245-
/O.CON.KFSD.SV.W.0008.000000T0000Z-170416T0245Z/
Woodbury IA-Ida IA-
908 PM CDT SAT APR 15 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM CDT
FOR SOUTHEASTERN WOODBURY AND SOUTHERN IDA COUNTIES...

At 908 PM CDT, a severe thunderstorm was located near Anthon, or 14
miles west of Ida Grove, moving southeast at 25 mph.

HAZARD...Quarter size hail. 

SOURCE...Radar indicated. 

IMPACT...Damage to vehicles is expected. 

This severe storm will be near...
  Danbury around 925 PM CDT. 
  Battle Creek around 930 PM CDT. 
  Ida Grove around 940 PM CDT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4237 9588 4245 9572 4232 9532 4221 9532
      4221 9572
TIME...MOT...LOC 0208Z 299DEG 23KT 4238 9576 

HAIL...1.00IN
WIND...<50MPH
 
$$

Hanko

680 
WWUS53 KFSD 160216
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
916 PM CDT SAT APR 15 2017

IAC093-193-160226-
/O.CAN.KFSD.SV.W.0008.000000T0000Z-170416T0245Z/
Woodbury IA-Ida IA-
916 PM CDT SAT APR 15 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN WOODBURY AND
SOUTHERN IDA COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning has been cancelled.  However small hail and
heavy rain are still possible with this thunderstorm.

LAT...LON 4237 9588 4245 9572 4232 9532 4221 9532
      4221 9572
TIME...MOT...LOC 0215Z 306DEG 27KT 4234 9569 

$$

Hanko

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 15, 7:00 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth	45 min
Apr 15, 7:36 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth	39 min
Apr 15, 8:09 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee, Ida, Plymouth, Woodbury	51 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2017 Every severe thunderstorm warning in 2017

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.