Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 42, NWS Sioux Falls, SD

May 4, 2012Cherokee County, O'Brien County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 4, 2012, 4:01 PM CDT for Cherokee County, O'Brien County, Iowa. It was in force for 29 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
May 4, 2012, 4:01 PM CDT (21:01 UTC)
Expired
May 4, 2012, 4:30 PM CDT
In force
29 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
1.25 in
Wind
60.0 mph

Counties Cherokee County, IA, O'Brien County, IA

The radar

The Sioux Falls radar (KFSD), 118 km from the middle of the area, began a volume at 21:02 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 4, 4:05 PM CDTTSTM WND DMG3 N Cleghorn, IAWIND DAMAGE NORTH OF CLEGHORN.

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 4, 2:00 PM CDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.0 hours before the alert went out and 192 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 12:00Z on 2012-05-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2705 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 12:00Z on 2012-05-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 10 square meters per square second.1939Sfc1 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
2705 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
584 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
10 m²/s²
0-3 km storm-relative helicity
98 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.

414 
WUUS53 KFSD 042101
SVRFSD
IAC035-141-042130-
/O.NEW.KFSD.SV.W.0042.120504T2101Z-120504T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
401 PM CDT FRI MAY 4 2012

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN CHEROKEE COUNTY IN NORTHWEST IOWA...
  SOUTHERN O'BRIEN COUNTY IN NORTHWEST IOWA...

* UNTIL 430 PM CDT

* AT 402 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE
  TRACKING A SEVERE THUNDERSTORM CAPABLE OF PRODUCING HALF DOLLAR
  SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
  LOCATED NEAR PAULLINA...OR 18 MILES EAST OF ORANGE CITY...AND
  MOVING EAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  LARRABEE AROUND 415 PM CDT...
  SUTHERLAND AROUND 420 PM CDT...

OTHER LOCATIONS IMPACTED BY THIS SEVERE THUNDERSTORM INCLUDE CALUMET.

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 4303 9539 4281 9539 4285 9585 4300 9581
TIME...MOT...LOC 2102Z 275DEG 24KT 4293 9566
WIND...HAIL 60MPH 1.25IN

$$

SCHUMACHER
2 follow-up statements
836 
WWUS53 KFSD 042122
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
422 PM CDT FRI MAY 4 2012

IAC035-141-042130-
/O.CON.KFSD.SV.W.0042.000000T0000Z-120504T2130Z/
O'BRIEN IA-CHEROKEE IA-
422 PM CDT FRI MAY 4 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHERN
CHEROKEE AND SOUTHERN O'BRIEN COUNTIES UNTIL 430 PM CDT...

AT 421 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
SUTHERLAND...OR 25 MILES SOUTHWEST OF SPENCER...MOVING EAST AT 30
MPH.

IN ADDITION...AT 405 PM CDT WIND DAMAGE WAS REPORTED BY LAW 
ENFORCEMENT NORTH OF CLEGHORN.

THIS SEVERE THUNDERSTORM WILL AFFECT MAINLY RURAL AREAS OF NORTHERN
CHEROKEE AND SOUTHERN O'BRIEN COUNTIES.

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 4303 9539 4281 9539 4285 9585 4300 9581
TIME...MOT...LOC 2121Z 275DEG 24KT 4292 9549
WIND...HAIL 60MPH 1.00IN

$$

SCHUMACHER
945 
WWUS53 KFSD 042128
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
428 PM CDT FRI MAY 4 2012

IAC035-141-042138-
/O.EXP.KFSD.SV.W.0042.000000T0000Z-120504T2130Z/
O'BRIEN IA-CHEROKEE IA-
428 PM CDT FRI MAY 4 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN CHEROKEE AND SOUTHERN
O'BRIEN COUNTIES WILL EXPIRE AT 430 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.

LAT...LON 4303 9539 4281 9539 4285 9585 4300 9581
TIME...MOT...LOC 2128Z 275DEG 24KT 4291 9543

$$

SCHUMACHER

The office that day

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

IssuedProductOfficeCountiesLasted
May 3, 7:57 PM CDTSevere Thunderstorm WarningFSDCherokee33 min
May 3, 8:05 PM CDTFlash Flood WarningFSDCherokee93 min
May 3, 8:37 PM CDTSevere Thunderstorm WarningFSDBuena Vista, Cherokee38 min
May 4, 3:00 PM CDTSevere Thunderstorm WarningFSDSioux30 min
May 4, 3:14 PM CDTSevere Thunderstorm WarningFSDPlymouth, Sioux31 min
May 4, 3:18 PM CDTSevere Thunderstorm WarningFSDO'Brien, Osceola, Sioux42 min
May 4, 3:20 PM CDTTornado WarningFSDO'Brien, Sioux25 min
May 4, 3:39 PM CDTSevere Thunderstorm WarningFSDPlymouth36 min
May 4, 3:43 PM CDTTornado WarningFSDO'Brien, Sioux32 min
May 4, 4:06 PM CDTTornado WarningFSDClay24 min
May 4, 4:09 PM CDTSevere Thunderstorm WarningFSDDickinson, Osceola51 min
May 4, 4:12 PM CDTSevere Thunderstorm WarningFSDClay, O'Brien33 min
May 4, 4:25 PM CDTSevere Thunderstorm WarningFSDClay35 min

Nearby

Severe Thunderstorm Warnings in Iowa, 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.