Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 77, NWS Des Moines, IA

May 6, 20124 counties in Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 6, 2012, 7:29 AM CDT for 4 counties in Iowa. It was in force for 31 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 6, 2012, 7:29 AM CDT (12:29 UTC)
Expired
May 6, 2012, 8:00 AM CDT
In force
31 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Adair County, IA, Dallas County, IA, Guthrie County, IA, Madison County, IA

The radar

The Des Moines radar (KDMX), 33 km from the middle of the area, began a volume at 12:28 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 6, 7:40 AM CDTTSTM WND DMGLinden, IAFIVE TO SIX 8 INCH IN DIAMETER TREE LIMBS DOWN ACROSS TOWN. TIME ESTIMATED BY RADAR.
May 6, 7:55 AM CDTTSTM WND DMG5 W Dallas Center, IAONE HALF OF A TREE SNAPPED OFF. SECTION OF TREE WAS ONE FOOT IN DIAMETER. NEIGHBOR WHO OBSERVED THE WINDS ESTIMATED THE WIND SPEED TO BE BETWEEN 55 AND 60 MPH.

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 6, 7:17 AM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 0.5 hours before the alert went out and 193 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 2012-05-06Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 2012-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -415 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
880 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
-415 m²/s²
0-3 km storm-relative helicity
-233 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.

652 
WUUS53 KDMX 061229
SVRDMX
IAC001-049-077-121-061300-
/O.NEW.KDMX.SV.W.0077.120506T1229Z-120506T1300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
729 AM CDT SUN MAY 6 2012

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN ADAIR COUNTY IN SOUTHWEST IOWA...
  DALLAS COUNTY IN CENTRAL IOWA...
  SOUTHEASTERN GUTHRIE COUNTY IN WEST CENTRAL IOWA...
  NORTHWESTERN MADISON COUNTY IN SOUTH CENTRAL IOWA...

* UNTIL 800 AM CDT

* AT 728 AM 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 NEAR
  STUART...OR 35 MILES NORTH OF CRESTON...AND MOVING EAST AT 45 MPH.

* LOCATIONS IMPACTED INCLUDE...
  EARLHAM...DE SOTO...ADEL...DALLAS CENTER...WAUKEE...LINDEN...
  DEXTER...REDFIELD...MINBURN...VAN METER AND GRANGER.

THIS INCLUDES INTERSTATE 80 BETWEEN MILE MARKERS 87 AND 121.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOVE TO AN INTERIOR ROOM AND STAY AWAY FROM WINDOWS. IF YOU ARE IN A
MOBILE HOME...GET OUT NOW...AND SEEK SHELTER IN A REINFORCED
BUILDING.

&&

LAT...LON 4168 9450 4180 9382 4160 9381 4160 9379
      4152 9379 4143 9441
TIME...MOT...LOC 1230Z 257DEG 39KT 4156 9431
WIND...HAIL 60MPH 1.00IN

$$

ZOGG
1 follow-up statement
107 
WWUS53 KDMX 061244
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
744 AM CDT SUN MAY 6 2012

IAC001-061255-
/O.CAN.KDMX.SV.W.0077.000000T0000Z-120506T1300Z/
ADAIR IA-
744 AM CDT SUN MAY 6 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN ADAIR COUNTY IS
CANCELLED...

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

LAT...LON 4146 9424 4150 9424 4151 9428 4156 9431
      4169 9443 4180 9382 4160 9381 4160 9379
      4152 9379
TIME...MOT...LOC 1245Z 257DEG 39KT 4160 9410

$$

IAC049-077-121-061300-
/O.CON.KDMX.SV.W.0077.000000T0000Z-120506T1300Z/
MADISON IA-GUTHRIE IA-DALLAS IA-
744 AM CDT SUN MAY 6 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR DALLAS...
SOUTHEASTERN GUTHRIE AND NORTHWESTERN MADISON COUNTIES UNTIL 800 AM
CDT...

AT 742 AM 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 6 MILES
WEST OF ADEL...OR 27 MILES WEST OF DES MOINES...MOVING EAST AT 45
MPH.

LOCATIONS IMPACTED INCLUDE...
  DE SOTO...ADEL...DALLAS CENTER...WAUKEE...MINBURN...VAN METER AND
  GRANGER.

THIS INCLUDES INTERSTATE 80 BETWEEN MILE MARKERS 97 AND 121.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4146 9424 4150 9424 4151 9428 4156 9431
      4169 9443 4180 9382 4160 9381 4160 9379
      4152 9379
TIME...MOT...LOC 1245Z 257DEG 39KT 4160 9410
WIND...HAIL 60MPH 1.00IN

$$

ZOGG

The office that day

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

IssuedProductOfficeCountiesLasted
May 6, 4:32 AM CDTSevere Thunderstorm WarningDMXHamilton, Wright43 min
May 6, 5:52 AM CDTSevere Thunderstorm WarningDMXAudubon, Guthrie53 min
May 6, 6:30 AM CDTSevere Thunderstorm WarningDMXAdair, Cass45 min
May 6, 7:05 AM CDTSevere Thunderstorm WarningDMXAdair, Dallas, Guthrie, Madison25 min
May 6, 7:09 AM CDTSevere Thunderstorm WarningDMXAdair, Madison22 min
May 6, 7:59 AM CDTSevere Thunderstorm WarningDMXDallas, Polk46 min
May 6, 8:27 AM CDTSevere Thunderstorm WarningDMXJasper, Marion, Polk, Warren48 min
May 6, 9:03 AM CDTSevere Thunderstorm WarningDMXJasper, Marion42 min
May 6, 9:12 AM CDTSevere Thunderstorm WarningDMXJasper, Marion48 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.