Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 113, NWS Sioux Falls, SD

May 23, 2012O'Brien County, Osceola County, Sioux County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 23, 2012, 9:11 PM CDT for O'Brien County, Osceola County, Sioux County, Iowa. It was in force for 34 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
May 23, 2012, 9:11 PM CDT (02:11 UTC)
Expired
May 23, 2012, 9:45 PM CDT
In force
34 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
1.0 in
Wind
58.0 mph

Counties O'Brien County, IA, Osceola County, IA, Sioux County, IA

The radar

The Sioux Falls radar (KFSD), 99 km from the middle of the area, began a volume at 02:11 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 23, 9:20 PM CDTHAIL 1.251 Ne Archer, IAHAIL LASTED UNTIL 925 PM
May 23, 9:22 PM CDTHAIL 0.754 W Primghar, IAHAIL LASTED FOR 3 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.

IssuedProductOfficeLasted
May 23, 4:07 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 2.2 hours before the alert went out and 215 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 2012-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1035 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 2012-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 195 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
1035 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
2387 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
195 m²/s²
0-3 km storm-relative helicity
291 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.7

Open this sounding in Storm Lab

The text

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

116 
WUUS53 KFSD 240211
SVRFSD
IAC141-143-167-240245-
/O.NEW.KFSD.SV.W.0113.120524T0211Z-120524T0245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
911 PM CDT WED MAY 23 2012

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  O'BRIEN COUNTY IN NORTHWEST IOWA...
  EASTERN OSCEOLA COUNTY IN NORTHWEST IOWA...
  EAST CENTRAL SIOUX COUNTY IN NORTHWEST IOWA...

* UNTIL 945 PM CDT

* AT 912 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE
  TRACKING A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
  HAIL.  THIS STORM WAS LOCATED NEAR ARCHER...OR 14 MILES NORTHEAST
  OF ORANGE CITY...AND MOVING NORTHEAST AT 45 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  PRIMGHAR AROUND 920 PM CDT...
  SANBORN AROUND 925 PM CDT...
  MELVIN AROUND 930 PM CDT...
  OCHEYEDAN AROUND 940 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 4296 9578 4312 9596 4348 9555 4328 9538
      4326 9539
TIME...MOT...LOC 0212Z 221DEG 40KT 4312 9582
WIND...HAIL <58MPH 1.00IN

$$

CHENARD
2 follow-up statements
916 
WWUS53 KFSD 240233
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
933 PM CDT WED MAY 23 2012

IAC167-240242-
/O.CAN.KFSD.SV.W.0113.000000T0000Z-120524T0245Z/
SIOUX IA-
933 PM CDT WED MAY 23 2012

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL SIOUX COUNTY IS
CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS /MOVED OUT OF THE WARNED 
AREA. ADDITIONAL THUNDERSTORMS ARE LIKELY THIS EVENING.

LAT...LON 4313 9556 4307 9564 4308 9564 4322 9571
      4335 9545 4328 9538 4326 9539
TIME...MOT...LOC 0232Z 244DEG 38KT 4319 9554

$$

IAC141-143-240245-
/O.CON.KFSD.SV.W.0113.000000T0000Z-120524T0245Z/
OSCEOLA IA-O'BRIEN IA-
933 PM CDT WED MAY 23 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHEASTERN
O'BRIEN AND SOUTHEASTERN OSCEOLA COUNTIES UNTIL 945 PM CDT...

AT 932 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
STORM WAS LOCATED NEAR SANBORN...OR 22 MILES WEST OF SPENCER...MOVING
NORTHEAST AT 45 MPH.

IN ADDITION...AT 920 PM HALF DOLLAR SIZE HAIL WAS REPORTED NEAR 
ARCHER WITH THIS STORM.

THIS SEVERE THUNDERSTORM WILL AFFECT MAINLY RURAL AREAS OF
NORTHEASTERN O'BRIEN AND SOUTHEASTERN OSCEOLA 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 4313 9556 4307 9564 4308 9564 4322 9571
      4335 9545 4328 9538 4326 9539
TIME...MOT...LOC 0232Z 244DEG 38KT 4319 9554
WIND...HAIL <58MPH 1.00IN

$$

CHENARD
148 
WWUS53 KFSD 240242
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
942 PM CDT WED MAY 23 2012

IAC141-143-240252-
/O.EXP.KFSD.SV.W.0113.000000T0000Z-120524T0245Z/
OSCEOLA IA-O'BRIEN IA-
942 PM CDT WED MAY 23 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN O'BRIEN AND
SOUTHEASTERN OSCEOLA COUNTIES WILL EXPIRE AT 945 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED 
AREA. ADDITIONAL THUNDERSTORMS ARE LIKELY TONIGHT.

LAT...LON 4313 9556 4307 9564 4308 9564 4322 9571
      4335 9545 4328 9538 4326 9539
TIME...MOT...LOC 0242Z 244DEG 38KT 4324 9541

$$

CHENARD

The office that day

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

IssuedProductOfficeCountiesLasted
May 23, 7:10 PM CDTSevere Thunderstorm WarningFSDLyon, Osceola35 min
May 23, 7:16 PM CDTSevere Thunderstorm WarningFSDIda27 min
May 23, 8:28 PM CDTSevere Thunderstorm WarningFSDOsceola32 min
May 24, 9:14 AM CDTRiver Flood WarningFSDSioux24 hr
May 24, 9:14 AM CDTRiver Flood WarningFSDPlymouth24 hr
May 24, 9:14 AM CDTRiver Flood WarningFSDLyon12 hr
May 24, 9:14 AM CDTRiver Flood WarningFSDClay24 hr
May 24, 9:14 AM CDTRiver Flood WarningFSDClay24 hr
May 24, 9:14 AM CDTRiver Flood WarningFSDBuena Vista, Clay69 hr

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.