Alert archive / Iowa / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 85, NWS Sioux Falls, SD

June 21, 2017Osceola County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jun 21, 2017, 10:47 PM CDT for Osceola County, Iowa. It was in force for 28 min. 2 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 21, 2017, 10:47 PM CDT (03:47 UTC)
Expired
Jun 21, 2017, 11:15 PM CDT
In force
28 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
1.25 in
Wind
50.0 mph

County Osceola County, IA

The radar

The Sioux Falls radar (KFSD), 97 km from the middle of the area, began a volume at 03:47 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

TimeReportWhereRemark
Jun 21, 10:50 PM CDTHAIL 14 Ene Sibley, IA
Jun 21, 10:58 PM CDTHAIL 0.884 W Ocheyedan, IA

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

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 3.8 hours before the alert went out and 225 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-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2017-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2017-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1414 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
205 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

826 
WUUS53 KFSD 220347
SVRFSD
IAC143-220415-
/O.NEW.KFSD.SV.W.0085.170622T0347Z-170622T0415Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
1047 PM CDT WED JUN 21 2017

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Osceola County in northwestern Iowa...

* Until 1115 PM CDT

* At 1047 PM CDT, a severe thunderstorm was located near Sibley,
  moving east at 15 mph.

  HAZARD...Half dollar size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Damage to vehicles is expected. 

* This severe thunderstorm will be near, 
  Ocheyedan and Harris around 1115 PM CDT. 

Other locations impacted by this severe thunderstorm include Bigelow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4327 9539 4339 9580 4350 9580 4350 9539
TIME...MOT...LOC 0347Z 284DEG 14KT 4343 9568 

HAIL...1.25IN
WIND...<50MPH
 
$$

JH
2 follow-up statements
990 
WWUS53 KFSD 220402
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1102 PM CDT WED JUN 21 2017

IAC143-220415-
/O.CON.KFSD.SV.W.0085.000000T0000Z-170622T0415Z/
Osceola IA-
1102 PM CDT WED JUN 21 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM CDT
FOR EASTERN OSCEOLA COUNTY...

At 1102 PM CDT, a severe thunderstorm was located near Ocheyedan, or 
9 miles east of Sibley, moving east at 20 mph.

HAZARD...Half dollar size hail. 

SOURCE...Radar indicated. 

IMPACT...Damage to vehicles is expected. 

This severe storm will be near...
  Ocheyedan around 1105 PM CDT. 
  Harris around 1115 PM CDT. 

Other locations impacted by this severe thunderstorm include Bigelow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and deadly cloud to ground
lightning. Seek shelter inside a well-built structure. Stay away from
windows.

&&

LAT...LON 4336 9571 4350 9571 4350 9539 4327 9539
TIME...MOT...LOC 0402Z 284DEG 18KT 4341 9556 

HAIL...1.25IN
WIND...<50MPH
 
$$

JH
119 
WWUS53 KFSD 220417
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1117 PM CDT WED JUN 21 2017

IAC143-220426-
/O.EXP.KFSD.SV.W.0085.000000T0000Z-170622T0415Z/
Osceola IA-
1117 PM CDT WED JUN 21 2017

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN OSCEOLA COUNTY HAS
EXPIRED...
                
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 allowed to expire.

LAT...LON 4336 9571 4350 9571 4350 9539 4327 9539
TIME...MOT...LOC 0416Z 284DEG 14KT 4340 9549 

$$

JH

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 10:17 PM CDTSevere Thunderstorm WarningFSDBuena Vista, Clay13 min
Jun 21, 11:33 PM CDTSevere Thunderstorm WarningFSDClay, Dickinson27 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2017Every 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.