Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 129, NWS Sioux Falls, SD

May 27, 2012Plymouth County, Sioux County, Iowa; Lincoln County, Union County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 27, 2012, 7:11 PM CDT for Plymouth County, Sioux County, Iowa; Lincoln County, Union County, South Dakota. It was in force for 34 min. 5 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
May 27, 2012, 7:11 PM CDT (00:11 UTC)
Expired
May 27, 2012, 7:45 PM CDT
In force
34 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Plymouth County, IA, Sioux County, IA, Lincoln County, SD, Union County, SD

The radar

The Sioux Falls radar (KFSD), 73 km from the middle of the area, began a volume at 00:12 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
May 27, 7:15 PM CDTTSTM WND DMG6 Nw Akron, SDHALF OF MAPLE TREE GONE
May 27, 7:15 PM CDTTSTM WND DMGAkron, IATREE DOWN ACROSS HIGHWAY 12 CAUSING ROAD CLOSURE
May 27, 7:15 PM CDTHAIL 1.56 Nw Akron, SD
May 27, 7:25 PM CDTTSTM WND DMG7 S Alcester, SDMULTIPLE TREES AND TREE BRANCHES DOWN
May 27, 7:28 PM CDTTSTM WND GST 60Ne Hawarden, IATREES DOWN IN HAWARDEN

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.

IssuedProductOfficeLasted
May 27, 3:42 PM CDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 0.2 hours before the alert went out and 181 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, Omaha, NE at 00:00Z on 2012-05-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 849 joules per kilogram.LCLLFCEL10008507005003002001001 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, Omaha, NE at 00:00Z on 2012-05-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 81 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
849 J/kg
Mixed-layer CIN
-92 J/kg
Mixed-layer LCL
2094 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
81 m²/s²
0-3 km storm-relative helicity
138 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

446 
WUUS53 KFSD 280011
SVRFSD
IAC149-167-SDC083-127-280045-
/O.NEW.KFSD.SV.W.0129.120528T0011Z-120528T0045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
711 PM CDT SUN MAY 27 2012

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN PLYMOUTH COUNTY IN NORTHWEST IOWA...
  WESTERN SIOUX COUNTY IN NORTHWEST IOWA...
  EASTERN LINCOLN COUNTY IN SOUTHEAST SOUTH DAKOTA...
  UNION COUNTY IN SOUTHEAST SOUTH DAKOTA...

* UNTIL 745 PM CDT

* AT 711 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE
  TRACKING A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED
  ALONG A LINE EXTENDING FROM 7 MILES SOUTHWEST OF ALCESTER TO AKRON
  TO JEFFERSON...AND MOVING NORTHEAST AT 45 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  HAWARDEN AROUND 725 PM CDT...
  NEWTON HILLS STATE PARK AND HUDSON AROUND 730 PM CDT...
  CRAIG...IRETON AND FAIRVIEW AROUND 735 PM CDT...
  CANTON AROUND 740 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 4249 9650 4272 9662 4288 9681 4309 9681
      4341 9665 4331 9653 4329 9655 4330 9658
      4327 9659 4326 9648 4301 9620 4256 9646
      4256 9650 4254 9647
TIME...MOT...LOC 0011Z 207DEG 41KT 4300 9670 4284 9652
          4269 9650
WIND...HAIL 60MPH <1.00IN

$$

BT
2 follow-up statements
747 
WWUS53 KFSD 280018
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
718 PM CDT SUN MAY 27 2012

IAC149-167-SDC083-127-280045-
/O.CON.KFSD.SV.W.0129.000000T0000Z-120528T0045Z/
SIOUX IA-PLYMOUTH IA-LINCOLN SD-UNION SD-
718 PM CDT SUN MAY 27 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR UNION...
EASTERN LINCOLN...WESTERN PLYMOUTH AND WESTERN SIOUX COUNTIES UNTIL
745 PM CDT...

AT 718 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING WALNUT SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM ALCESTER TO 6 MILES NORTHEAST OF
AKRON TO 8 MILES SOUTHEAST OF AKRON...MOVING NORTHEAST AT 45 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  HAWARDEN AROUND 725 PM CDT...
  NEWTON HILLS STATE PARK AND HUDSON AROUND 730 PM CDT...
  CRAIG...IRETON AND FAIRVIEW AROUND 735 PM CDT...
  CANTON AROUND 740 PM CDT...

AT 715 PM...A TRAINED SPOTTER REPORTED WALNUT SIZED HAIL AND TREES 
DAMAGED BY STRONG WINDS SIX MILES NORTHWEST OF AKRON. 


PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE IMMEDIATELY FOR LARGE HAIL AND DAMAGING WINDS IF YOU ARE IN
THE PATH OF THIS STORM. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 4249 9650 4272 9662 4288 9681 4309 9681
      4341 9665 4331 9653 4329 9655 4330 9658
      4327 9659 4326 9648 4301 9620 4256 9646
      4256 9650 4254 9647
TIME...MOT...LOC 0018Z 207DEG 41KT 4307 9665 4291 9647
          4276 9645
WIND...HAIL 60MPH 1.50IN

$$

BT
278 
WWUS53 KFSD 280024
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
724 PM CDT SUN MAY 27 2012

IAC149-167-SDC083-127-280045-
/O.CON.KFSD.SV.W.0129.000000T0000Z-120528T0045Z/
SIOUX IA-PLYMOUTH IA-LINCOLN SD-UNION SD-
724 PM CDT SUN MAY 27 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR UNION...
EASTERN LINCOLN...WESTERN PLYMOUTH AND WESTERN SIOUX COUNTIES UNTIL
745 PM CDT...

AT 725 PM CDT...A LINE OF SEVERE THUNDERSTORMS WAS REPORTED...
PRODUCING  WALNUT SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.
 THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 5 MILES NORTH
OF ALCESTER TO HAWARDEN TO 7 MILES EAST OF AKRON...MOVING NORTHEAST
AT 45 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  NEWTON HILLS STATE PARK AND HUDSON AROUND 730 PM CDT...
  CRAIG...IRETON AND FAIRVIEW AROUND 735 PM CDT...
  CANTON AROUND 740 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE IMMEDIATELY FOR LARGE HAIL AND DAMAGING WINDS IF YOU ARE IN
THE PATH OF THIS STORM. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 4249 9650 4272 9662 4288 9681 4309 9681
      4341 9665 4331 9653 4329 9655 4330 9658
      4327 9659 4326 9648 4301 9620 4256 9646
      4256 9650 4254 9647
TIME...MOT...LOC 0025Z 207DEG 41KT 4314 9660 4298 9642
          4283 9640
WIND...HAIL 60MPH 1.50IN

$$


BT

The office that day

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

IssuedProductOfficeCountiesLasted
May 27, 7:22 PM CDTFlash Flood WarningFSDLyon, Plymouth, Sioux7 hr
May 27, 7:31 PM CDTSevere Thunderstorm WarningFSDLyon, Plymouth, Sioux29 min
May 27, 7:54 PM CDTSevere Thunderstorm WarningFSDLyon, O'Brien, Osceola, Sioux36 min
May 27, 8:19 PM CDTFlash Flood WarningFSDLyon, Osceola7 hr
May 27, 8:54 PM CDTSevere Thunderstorm WarningFSDDickinson36 min
May 27, 9:18 PM CDTSevere Thunderstorm WarningFSDPlymouth27 min
May 27, 9:42 PM CDTSevere Thunderstorm WarningFSDPlymouth, Woodbury10 min
May 28, 5:35 AM CDTRiver Flood WarningFSDLyon52 hr
May 28, 5:35 AM CDTRiver Flood WarningFSDClay71 hr
May 28, 5:35 AM CDTRiver Flood WarningFSDClay8 days
May 28, 5:35 AM CDTRiver Flood WarningFSDBuena Vista, Clay9 days
May 27, 9:32 PM CDTFlash Flood WarningFSDClay, Union4 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2012Severe Thunderstorm Warnings in South Dakota, 2012Every severe thunderstorm warning in 2012

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.