Alert archive / Iowa / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 21, NWS Sioux Falls, SD

June 27, 2019Lyon County, Sioux County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jun 27, 2019, 8:22 AM CDT for Lyon County, Sioux County, Iowa. It was in force for 23 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: Jun 27, 2019, 8:22 AM CDT (13:22 UTC)
Expired: Jun 27, 2019, 8:45 AM CDT
In force: 23 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Hail: 0.75 in
Wind: 70.0 mph

Counties Lyon County, IA, Sioux County, IA

The radar

The Sioux Falls radar (KFSD), 50 km from the middle of the area, began a volume at 13:22 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 27, 8:23 AM CDT	HAIL 1	1 Wsw Lester, IA	RECEIVED REPORT VIA SOCIAL MEDIA, QUARTER SIZED HAIL FELL FOR ABOUT 4 MINUTES.

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
Jun 27, 4:01 AM CDT	Severe Thunderstorm Watch	SPC	9 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 1.4 hours before the alert went out and 212 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: 2685 J/kg
Mixed-layer CIN: -256 J/kg
Mixed-layer LCL: 1211 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 27 m²/s²
0-3 km storm-relative helicity: 33 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.2

Open this sounding in Storm Lab

The text

As transmitted.

132 
WUUS53 KFSD 271322
SVRFSD
IAC119-167-271345-
/O.NEW.KFSD.SV.W.0021.190627T1322Z-190627T1345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
822 AM CDT Thu Jun 27 2019

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Southern Lyon County in northwestern Iowa...
  Northern Sioux County in northwestern Iowa...

* Until 845 AM CDT.

* At 821 AM CDT, a severe thunderstorm was located over Alvord, or 10
  miles southwest of Rock Rapids, moving east at 40 mph.

  HAZARD...70 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* This severe thunderstorm will be near...
  Rock Valley and Doon around 830 AM CDT.
  Hull and George around 840 AM CDT.
  Boyden and Matlock around 845 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4320 9648 4321 9647 4322 9648 4322 9652
      4323 9654 4344 9638 4333 9586 4301 9597
TIME...MOT...LOC 1321Z 291DEG 37KT 4332 9631 

HAIL...<.75IN
WIND...70MPH
 
$$

Schumacher

3 follow-up statements

978 
WWUS53 KFSD 271325
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
825 AM CDT Thu Jun 27 2019

IAC119-167-271345-
/O.CON.KFSD.SV.W.0021.000000T0000Z-190627T1345Z/
Lyon IA-Sioux IA-
825 AM CDT Thu Jun 27 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 AM CDT
FOR SOUTHERN LYON AND NORTHERN SIOUX COUNTIES...

At 825 AM CDT, a severe thunderstorm was located over Doon, or 9
miles southwest of Rock Rapids, moving east at 45 mph.

HAZARD...70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

This severe storm will be near...
  Hull around 835 AM CDT.
  George around 840 AM CDT.
  Boyden and Matlock around 845 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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

&&

LAT...LON 4320 9648 4321 9647 4322 9648 4322 9652
      4323 9654 4344 9638 4333 9586 4301 9597
TIME...MOT...LOC 1325Z 291DEG 37KT 4331 9626 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...70MPH
 
$$

Schumacher

057 
WWUS53 KFSD 271333
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
833 AM CDT Thu Jun 27 2019

IAC119-167-271345-
/O.CON.KFSD.SV.W.0021.000000T0000Z-190627T1345Z/
Lyon IA-Sioux IA-
833 AM CDT Thu Jun 27 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 AM CDT
FOR SOUTHERN LYON AND NORTHERN SIOUX COUNTIES...

At 833 AM CDT, a severe thunderstorm was located near Doon, or 10
miles south of Rock Rapids, moving east at 45 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

This severe storm will be near...
  George around 840 AM CDT.
  Boyden and Matlock around 845 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4320 9648 4321 9647 4322 9648 4322 9652
      4323 9654 4344 9638 4333 9586 4301 9597
TIME...MOT...LOC 1333Z 291DEG 37KT 4328 9615 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...70MPH
 
$$

Schumacher

079 
WWUS53 KFSD 271347
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
847 AM CDT Thu Jun 27 2019

IAC119-167-271356-
/O.EXP.KFSD.SV.W.0021.000000T0000Z-190627T1345Z/
Lyon IA-Sioux IA-
847 AM CDT Thu Jun 27 2019

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN LYON AND NORTHERN
SIOUX COUNTIES HAS EXPIRED...
        
The storm which prompted the warning has moved out of the western 
Lyon County.  Therefore, the warning has been allowed to expire.  

Remember, a Severe Thunderstorm Warning still remains in effect for
eastern Lyon County and Sioux County until 930 AM CDT

A Severe Thunderstorm Watch remains in effect until 100 PM CDT for
northwestern Iowa...and southeastern South Dakota.

LAT...LON 4320 9648 4321 9647 4322 9648 4322 9652
      4323 9654 4344 9638 4333 9586 4301 9597
TIME...MOT...LOC 1346Z 291DEG 37KT 4323 9599 

$$

Schumacher

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 27, 8:18 AM CDT	Flash Flood Warning	FSD	Lyon	117 min
Jun 27, 8:30 AM CDT	Severe Thunderstorm Warning	FSD	Lyon	30 min
Jun 27, 8:40 AM CDT	Severe Thunderstorm Warning	FSD	Lyon, O'Brien, Osceola, Sioux	50 min
Jun 27, 9:14 AM CDT	Flash Flood Warning	FSD	Lyon, Sioux	3 hr
Jun 27, 12:33 PM CDT	Severe Thunderstorm Warning	FSD	Clay, Dickinson, O'Brien, Osceola	42 min
Jun 27, 12:36 PM CDT	River Flood Warning	FSD	Plymouth, Sioux	4 days
Jun 27, 12:36 PM CDT	River Flood Warning	FSD	Plymouth	31 days
Jun 27, 12:36 PM CDT	River Flood Warning	FSD	Lyon	32 hr
Jun 27, 2:26 PM CDT	River Flood Warning	FSD	Lyon	7 hr
Jun 27, 3:15 PM CDT	Heat Advisory	FSD	Plymouth, Sioux, Woodbury	29 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2019 Every severe thunderstorm warning in 2019

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.