Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 67, NWS Des Moines, IA

May 4, 2012Palo Alto County, Pocahontas County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 4, 2012, 10:27 PM CDT for Palo Alto County, Pocahontas County, Iowa. It was in force for 48 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, 10:27 PM CDT (03:27 UTC)
Expired
May 4, 2012, 11:15 PM CDT
In force
48 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Palo Alto County, IA, Pocahontas County, IA

The radar

The Des Moines radar (KDMX), 150 km from the middle of the area, began a volume at 03:27 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, 10:55 PM CDTHAIL 1.75Pocahontas, IARELAYED BY THE POCAHONTAS CASEYS. CUSTOMER REPORTED GOLF BALL SIZED HAIL ON NORTH SIDE OF TOWN. HALF DOLLAR SIZED HAIL REPORTED AT THE CASEYS LOCATION.

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

Minneapolis, MN (KMPX), launched 00:00Z, 3.5 hours before the alert went out and 227 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, Minneapolis, MN at 00:00Z on 2012-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Minneapolis, MN at 00:00Z on 2012-05-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 70 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1132 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
274 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.

779 
WUUS53 KDMX 050327
SVRDMX
IAC147-151-050415-
/O.NEW.KDMX.SV.W.0067.120505T0327Z-120505T0415Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1027 PM CDT FRI MAY 4 2012

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN PALO ALTO COUNTY IN NORTHWEST IOWA...
  NORTHERN POCAHONTAS COUNTY IN NORTHWEST IOWA...

* UNTIL 1115 PM CDT

* AT 1023 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED 7 MILES EAST OF LAURENS...OR 28 MILES SOUTHWEST
  OF ALGONA...AND MOVING NORTHEAST AT 20 MPH.

* LOCATIONS IMPACTED INCLUDE...
  PLOVER...MALLARD...ROLFE...WEST BEND AND RODMAN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

LARGE HAIL CAN CAUSE INJURY AND PROPERTY DAMAGE. SEEK SAFETY INDOORS
UNTIL THE STORM PASSES.

&&

LAT...LON 4310 9444 4280 9444 4266 9461 4279 9492
      4313 9445
TIME...MOT...LOC 0328Z 232DEG 16KT 4287 9468
WIND...HAIL <50MPH 1.00IN

$$

COGIL
4 follow-up statements
133 
WWUS53 KDMX 050337
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1037 PM CDT FRI MAY 4 2012

IAC147-151-050415-
/O.CON.KDMX.SV.W.0067.000000T0000Z-120505T0415Z/
POCAHONTAS IA-PALO ALTO IA-
1037 PM CDT FRI MAY 4 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHEASTERN
PALO ALTO AND NORTHERN POCAHONTAS COUNTIES UNTIL 1115 PM CDT...

AT 1034 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
STORM WAS LOCATED 10 MILES NORTH OF POCAHONTAS...OR 24 MILES
SOUTHWEST OF ALGONA...MOVING EAST AT 25 MPH.

LOCATIONS IMPACTED INCLUDE...
  ROLFE AND WEST BEND.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE FOR LARGE HAIL AND DEADLY CLOUD TO GROUND LIGHTNING. PEOPLE
OUTSIDE SHOULD MOVE TO A REINFORCED BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 4279 9488 4304 9444 4280 9444 4266 9461
TIME...MOT...LOC 0337Z 252DEG 20KT 4288 9459
WIND...HAIL <50MPH 1.00IN

$$

COGIL
533 
WWUS53 KDMX 050349
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1049 PM CDT FRI MAY 4 2012

IAC147-151-050415-
/O.CON.KDMX.SV.W.0067.000000T0000Z-120505T0415Z/
POCAHONTAS IA-PALO ALTO IA-
1049 PM CDT FRI MAY 4 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHEASTERN
PALO ALTO AND NORTHERN POCAHONTAS COUNTIES UNTIL 1115 PM CDT...

AT 1045 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING PING PONG BALL SIZE HAIL. 
THIS STORM WAS LOCATED NEAR POCAHONTAS...OR 26 MILES EAST OF STORM
LAKE...MOVING SOUTHEAST AT 10 MPH.

LOCATIONS IMPACTED INCLUDE...
  POCAHONTAS...WEST BEND AND ROLFE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. PREPARE IMMEDIATELY FOR LARGE DESTRUCTIVE
HAIL CAPABLE OF PRODUCING SIGNIFICANT DAMAGE AND INJURY. PEOPLE
OUTSIDE SHOULD SEEK SHELTER IMMEDIATELY...PREFERABLY INSIDE A
REINFORCED BUILDING. STAY AWAY FROM WINDOWS.

&&

LAT...LON 4304 9444 4280 9444 4266 9461 4275 9481
      4285 9471
TIME...MOT...LOC 0350Z 296DEG 10KT 4275 9469
WIND...HAIL <50MPH 1.50IN

$$

COGIL
604 
WWUS53 KDMX 050356
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1056 PM CDT FRI MAY 4 2012

IAC147-050406-
/O.CAN.KDMX.SV.W.0067.000000T0000Z-120505T0415Z/
PALO ALTO IA-
1056 PM CDT FRI MAY 4 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN PALO ALTO COUNTY
IS CANCELLED...

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

LAT...LON 4280 9471 4279 9464 4275 9450 4266 9461
      4274 9478
TIME...MOT...LOC 0356Z 304DEG 9KT 4275 9469

$$

IAC151-050415-
/O.CON.KDMX.SV.W.0067.000000T0000Z-120505T0415Z/
POCAHONTAS IA-
1056 PM CDT FRI MAY 4 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL
POCAHONTAS COUNTY UNTIL 1115 PM CDT...

AT 1053 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING PING PONG BALL SIZE HAIL. 
THIS STORM WAS LOCATED NEAR POCAHONTAS...OR 27 MILES EAST OF STORM
LAKE...MOVING SOUTHEAST AT 10 MPH.

LOCATIONS IMPACTED INCLUDE...
  POCAHONTAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. PREPARE IMMEDIATELY FOR LARGE DESTRUCTIVE
HAIL CAPABLE OF PRODUCING SIGNIFICANT DAMAGE AND INJURY. PEOPLE
OUTSIDE SHOULD SEEK SHELTER IMMEDIATELY...PREFERABLY INSIDE A
REINFORCED BUILDING. STAY AWAY FROM WINDOWS.

&&

LAT...LON 4280 9471 4279 9464 4275 9450 4266 9461
      4274 9478
TIME...MOT...LOC 0356Z 304DEG 9KT 4275 9469
WIND...HAIL <50MPH 1.50IN

$$

COGIL
387 
WWUS53 KDMX 050416
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1116 PM CDT FRI MAY 4 2012

IAC151-050426-
/O.EXP.KDMX.SV.W.0067.000000T0000Z-120505T0415Z/
POCAHONTAS IA-
1116 PM CDT FRI MAY 4 2012

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL POCAHONTAS COUNTY HAS
EXPIRED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.

LAT...LON 4280 9471 4279 9464 4275 9450 4266 9461
      4274 9478
TIME...MOT...LOC 0356Z 304DEG 9KT 4275 9469

$$

COGIL

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 5, 2:31 AM CDTSevere Thunderstorm WarningDMXCarroll, Crawford33 min
May 5, 1:57 PM CDTSevere Thunderstorm WarningDMXKossuth, Winnebago33 min
May 5, 2:28 PM CDTSevere Thunderstorm WarningDMXWinnebago32 min
May 5, 2:54 PM CDTSevere Thunderstorm WarningDMXCerro Gordo, Winnebago, Worth66 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.