Alert archive / Iowa / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 113, NWS Sioux Falls, SD

July 7, 2009Plymouth County, Woodbury County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 7, 2009, 10:22 PM CDT for Plymouth County, Woodbury County, Iowa. It was in force for 38 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
Jul 7, 2009, 10:22 PM CDT (03:22 UTC)
Expired
Jul 7, 2009, 11:00 PM CDT
In force
38 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon

Counties Plymouth County, IA, Woodbury County, IA

The radar

The Omaha radar (KOAX), 132 km from the middle of the area, began a volume at 03:26 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
Jul 7, 10:30 PM CDTTSTM WND DMG3 Se Hinton, IA3 TO 4 INCH DIAMETER TREE BRANCHES DOWNED BY STRONG WINDS.

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
Jul 7, 9:44 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 3.4 hours before the alert went out and 132 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 2009-07-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 27 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 2009-07-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 32 square meters per square second.193958Sfc1 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
27 J/kg
Mixed-layer CIN
-201 J/kg
Mixed-layer LCL
2298 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
32 m²/s²
0-3 km storm-relative helicity
157 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

347 
WUUS53 KFSD 080322
SVRFSD
IAC149-193-080400-
/O.NEW.KFSD.SV.W.0113.090708T0322Z-090708T0400Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1022 PM CDT TUE JUL 7 2009

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN PLYMOUTH COUNTY IN NORTHWEST IOWA
  WESTERN WOODBURY COUNTY IN NORTHWEST IOWA

* UNTIL 1100 PM CDT

* AT 1020 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED 4 MILES
  SOUTHEAST OF HINTON...OR 8 MILES NORTHEAST OF SIOUX CITY...AND WAS
  MOVING SOUTHEAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  LAWTON AROUND 1040 PM CDT...
  MOVILLE AROUND 1045 PM CDT...

THIS WARNING REPLACES THE PREVIOUS WARNING FOR THE AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...AS WELL AS DESTRUCTIVE HAIL...BY
MOVING TO A STRONG SHELTER. A WELL BUILT PERMANENT BUILDING IS
BEST...PREFERABLY TOWARD THE INSIDE OF THE BUILDING AND AWAY FROM
OUTSIDE WALLS AND WINDOWS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 300 AM CDT
WEDNESDAY MORNING FOR NORTHWEST IOWA AND NORTHEAST NEBRASKA AND
SOUTHEAST SOUTH DAKOTA.

&&

LAT...LON 4240 9589 4230 9621 4263 9645 4272 9616
TIME...MOT...LOC 0322Z 333DEG 22KT 4256 9626

$$

RSR
2 follow-up statements
000 
WWUS53 KFSD 080341
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1041 PM CDT TUE JUL 7 2009

IAC149-193-080400-
/O.CON.KFSD.SV.W.0113.000000T0000Z-090708T0400Z/
PLYMOUTH IA-WOODBURY IA-
1041 PM CDT TUE JUL 7 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM CDT
FOR NORTHWESTERN WOODBURY AND SOUTHERN PLYMOUTH COUNTIES...

AT 1040 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL. THIS STORM WAS LOCATED NEAR LAWTON...OR 9 MILES EAST OF SIOUX
CITY...MOVING SOUTHEAST AT 20 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
LAWTON AROUND 1050 PM CDT...
BRONSON AROUND 1100 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 300 AM CDT
WEDNESDAY MORNING FOR NORTHWEST IOWA AND NORTHEAST NEBRASKA AND
SOUTHEAST SOUTH DAKOTA.

&&

LAT...LON 4240 9589 4230 9621 4263 9645 4272 9616
TIME...MOT...LOC 0341Z 332DEG 17KT 4251 9622

$$

RSR
000 
WWUS53 KFSD 080402
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1102 PM CDT TUE JUL 7 2009

IAC149-193-080412-
/O.EXP.KFSD.SV.W.0113.000000T0000Z-090708T0400Z/
PLYMOUTH IA-WOODBURY IA-
1102 PM CDT TUE JUL 7 2009

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN WOODBURY AND
SOUTHERN PLYMOUTH COUNTIES EXPIRED AT 1100 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED AND NO LONGER
APPEARED TO BE SEVERE.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 300 AM CDT
WEDNESDAY MORNING FOR NORTHWEST IOWA AND NORTHEAST NEBRASKA AND
SOUTHEAST SOUTH DAKOTA.

LAT...LON 4240 9589 4230 9621 4263 9645 4272 9616
TIME...MOT...LOC 0341Z 332DEG 17KT 4251 9622

$$

RSR

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 7, 7:51 PM CDTSevere Thunderstorm WarningFSDLyon, Sioux39 min
Jul 7, 8:02 PM CDTSevere Thunderstorm WarningFSDSioux43 min
Jul 7, 8:23 PM CDTSevere Thunderstorm WarningFSDClay, O'Brien52 min
Jul 7, 8:39 PM CDTFlash Flood WarningFSDBuena Vista, Cherokee, Clay, O'Brien, Plymouth, Sioux3 hr
Jul 7, 8:39 PM CDTSevere Thunderstorm WarningFSDBuena Vista, Clay51 min
Jul 7, 8:44 PM CDTSevere Thunderstorm WarningFSDPlymouth, Sioux46 min
Jul 7, 8:58 PM CDTSevere Thunderstorm WarningFSDSioux32 min
Jul 7, 9:10 PM CDTFlash Flood WarningFSDBuena Vista, Cherokee, Plymouth3 hr
Jul 7, 9:53 PM CDTSevere Thunderstorm WarningFSDPlymouth, Woodbury37 min
Jul 7, 10:14 PM CDTFlash Flood WarningFSDIda, Woodbury3 hr
Jul 8, 2:12 AM CDTFlash Flood WarningFSDPlymouth, Woodbury3 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2009Every severe thunderstorm warning in 2009

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.