Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 74, NWS Des Moines, IA

May 6, 2012Adair County, Cass County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 6, 2012, 6:30 AM CDT for Adair County, Cass County, Iowa. It was in force for 45 min. 3 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, 6:30 AM CDT (11:30 UTC)
Expired
May 6, 2012, 7:15 AM CDT
In force
45 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Adair County, IA, Cass County, IA

The radar

The Des Moines radar (KDMX), 109 km from the middle of the area, began a volume at 11:33 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, 6:30 AM CDTTSTM WND DMGAtlantic, IASOME SHINGLES BLOWN OFF ROOFS...ABOUT 12 TO 14 ONE FOOT DIAMETER TREES SNAPPED. TIME ESTIMATED FROM RADAR.
May 6, 6:31 AM CDTTSTM WND GST 69Atlantic, IAA FEW SHINGLES BLOWN OFF HOUSE. TREE BRANCHES DOWN...SIZE UNKNOWN.
May 6, 7:05 AM CDTTSTM WND GST 656 Wsw Greenfield, IAMEASURED BY KCCI SCHOOLNET SITE AT NODAWAY VALLEY SCHOOL.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 11.5 hours before the alert went out and 122 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 2012-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2892 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 2012-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 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
2892 J/kg
Mixed-layer CIN
-51 J/kg
Mixed-layer LCL
1936 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.1
Supercell composite
6.4

Open this sounding in Storm Lab

The text

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

864 
WUUS53 KDMX 061130
SVRDMX
IAC001-029-061215-
/O.NEW.KDMX.SV.W.0074.120506T1130Z-120506T1215Z/

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

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN ADAIR COUNTY IN SOUTHWEST IOWA...
  CASS COUNTY IN SOUTHWEST IOWA...

* UNTIL 715 AM CDT

* AT 629 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
  ATLANTIC...AND MOVING EAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  CUMBERLAND...WIOTA...MASSENA...ANITA...BRIDGEWATER AND FONTANELLE.

THIS INCLUDES INTERSTATE 80 BETWEEN MILE MARKERS 79 AND 82.

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 4144 9514 4150 9453 4116 9451 4115 9500
      4116 9513
TIME...MOT...LOC 1130Z 262DEG 30KT 4133 9501
WIND...HAIL 60MPH 1.00IN

$$

ZOGG
3 follow-up statements
886 
WWUS53 KDMX 061141
SVSDMX

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

IAC001-029-061215-
/O.CON.KDMX.SV.W.0074.000000T0000Z-120506T1215Z/
ADAIR IA-CASS IA-
641 AM CDT SUN MAY 6 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CASS AND
WESTERN ADAIR COUNTIES UNTIL 715 AM CDT...

AT 638 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
SOUTHEAST OF ATLANTIC...MOVING EAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  MASSENA...ANITA...BRIDGEWATER AND FONTANELLE.

THIS INCLUDES INTERSTATE 80 BETWEEN MILE MARKERS 76 AND 81.

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 4150 9453 4116 9451 4115 9500 4133 9503
      4144 9510
TIME...MOT...LOC 1142Z 262DEG 30KT 4134 9488
WIND...HAIL 60MPH 1.00IN

$$

ZOGG
595 
WWUS53 KDMX 061151
SVSDMX

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

IAC001-029-061215-
/O.CON.KDMX.SV.W.0074.000000T0000Z-120506T1215Z/
ADAIR IA-CASS IA-
651 AM CDT SUN MAY 6 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR EASTERN CASS
AND WESTERN ADAIR COUNTIES UNTIL 715 AM CDT...

AT 647 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 11 MILES
EAST OF ATLANTIC...MOVING EAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  ANITA...BRIDGEWATER AND FONTANELLE.

THIS INCLUDES INTERSTATE 80 BETWEEN MILE MARKERS 76 AND 81.

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 4116 9492 4133 9492 4145 9502 4150 9453
      4116 9451
TIME...MOT...LOC 1151Z 262DEG 30KT 4135 9478
WIND...HAIL 60MPH 1.00IN

$$

ZOGG
863 
WWUS53 KDMX 061158
SVSDMX

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

IAC001-029-061215-
/O.CON.KDMX.SV.W.0074.000000T0000Z-120506T1215Z/
ADAIR IA-CASS IA-
658 AM CDT SUN MAY 6 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR EASTERN CASS
AND WESTERN ADAIR COUNTIES UNTIL 715 AM CDT...

AT 656 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 14 MILES
WEST OF GREENFIELD...OR 15 MILES EAST OF ATLANTIC...MOVING EAST AT 35
MPH.

LOCATIONS IMPACTED INCLUDE...
  BRIDGEWATER AND FONTANELLE.

THIS INCLUDES INTERSTATE 80 BETWEEN MILE MARKERS 76 AND 81.

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 4117 9476 4136 9480 4146 9490 4150 9453
      4116 9451
TIME...MOT...LOC 1158Z 262DEG 30KT 4136 9470
WIND...HAIL 60MPH 1.00IN

$$

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, 7:05 AM CDTSevere Thunderstorm WarningDMXAdair, Dallas, Guthrie, Madison25 min
May 6, 7:09 AM CDTSevere Thunderstorm WarningDMXAdair, Madison22 min
May 6, 7:29 AM CDTSevere Thunderstorm WarningDMXAdair, Dallas, Guthrie, Madison31 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.