Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 142, NWS Des Moines, IA

July 25, 20126 counties in Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 25, 2012, 8:09 PM CDT for 6 counties in Iowa. It was in force for 51 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: Jul 25, 2012, 8:09 PM CDT (01:09 UTC)
Expired: Jul 25, 2012, 9:00 PM CDT
In force: 51 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Cerro Gordo County, IA, Franklin County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Wright County, IA

The radar

The Des Moines radar (KDMX), 105 km from the middle of the area, began a volume at 01:08 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

Time	Report	Where	Remark
Jul 25, 8:30 PM CDT	TSTM WND DMG	Thornton, IA	LOTS OF TREES DOWN INCLUDING ONE POSSIBLY ON FIRE. SOME BROKEN WINDOWS TOO. FROM KIMT TV VIEWER. TIME ESTIMATED.
Jul 25, 8:40 PM CDT	TSTM WND DMG	Meservey, IA	CORN BINS BLOWN ONTO THE ROAD.

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.

Issued	Product	Office	Lasted
Jul 25, 5:16 PM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 1.2 hours before the alert went out and 251 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 837 J/kg
Mixed-layer CIN: -60 J/kg
Mixed-layer LCL: 1266 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: -72 m²/s²
0-3 km storm-relative helicity: 59 m²/s²
Significant tornado parameter: -0.2
Supercell composite: -3.3

Open this sounding in Storm Lab

The text

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

949 
WUUS53 KDMX 260109
SVRDMX
IAC033-069-079-081-083-197-260200-
/O.NEW.KDMX.SV.W.0142.120726T0109Z-120726T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
809 PM CDT WED JUL 25 2012

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN CERRO GORDO COUNTY IN NORTH CENTRAL IOWA...
  FRANKLIN COUNTY IN NORTH CENTRAL IOWA...
  NORTHEASTERN HAMILTON COUNTY IN CENTRAL IOWA...
  SOUTHEASTERN HANCOCK COUNTY IN NORTH CENTRAL IOWA...
  NORTHERN HARDIN COUNTY IN CENTRAL IOWA...
  EASTERN WRIGHT COUNTY IN NORTH CENTRAL IOWA...

* UNTIL 900 PM CDT

* AT 804 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
  LOCATED ALONG A LINE EXTENDING FROM 6 MILES SOUTHWEST OF CLEAR LAKE
  TO 8 MILES NORTH OF JEWELL...AND MOVING EAST AT 45 MPH. 

* LOCATIONS IMPACTED INCLUDE...
  IOWA FALLS...ROCKWELL...SHEFFIELD...HAMPTON...ELDORA...THORNTON...
  POPEJOY...SWALEDALE...LATIMER...COULTER...ALDEN...BUCKEYE...
  OWASA...GENEVA...HANSELL...DOUGHERTY...ACKLEY AND STEAMBOAT ROCK.

WIND DAMAGE COULD OCCUR OUT AHEAD OF THE MAIN STORM. 

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 137 AND 190.

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 4247 9303 4247 9301 4236 9301 4236 9370
      4255 9370 4308 9350 4311 9302
TIME...MOT...LOC 0109Z 275DEG 41KT 4307 9339 4243 9357
WIND...HAIL 60MPH 1.00IN

$$

JUNGBLUTH

2 follow-up statements

657 
WWUS53 KDMX 260117
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
817 PM CDT WED JUL 25 2012

IAC033-069-079-081-083-197-260200-
/O.CON.KDMX.SV.W.0142.000000T0000Z-120726T0200Z/
HARDIN IA-HANCOCK IA-HAMILTON IA-FRANKLIN IA-CERRO GORDO IA-WRIGHT IA-
817 PM CDT WED JUL 25 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR EASTERN
WRIGHT...SOUTHERN CERRO GORDO...FRANKLIN...NORTHEASTERN HAMILTON...
SOUTHEASTERN HANCOCK AND NORTHERN HARDIN COUNTIES UNTIL 900 PM CDT...

AT 813 PM 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
BELMOND...OR 25 MILES NORTHWEST OF IOWA FALLS...MOVING EAST AT 35
MPH.

LOCATIONS IMPACTED INCLUDE...
  IOWA FALLS...SHEFFIELD...ROCKWELL...HAMPTON...THORNTON...POPEJOY...
  LATIMER...COULTER...SWALEDALE...ALDEN...BUCKEYE...OWASA...GENEVA...
  HANSELL...DOUGHERTY...ACKLEY AND STEAMBOAT ROCK.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 137 AND 190.

IN ADDITION TO THE STORM NEAR BELMOND...WINDS COULD GUST TO 60 MPH 
ALONG THE INTERSTATE 35 CORRIDOR EAST OF THE STORM. 

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 4247 9303 4247 9301 4236 9301 4236 9370
      4255 9370 4308 9350 4311 9302
TIME...MOT...LOC 0117Z 278DEG 31KT 4283 9348
WIND...HAIL 60MPH 1.00IN

$$

JUNGBLUTH

535 
WWUS53 KDMX 260149
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
849 PM CDT WED JUL 25 2012

IAC033-069-079-081-083-197-260200-
/O.CON.KDMX.SV.W.0142.000000T0000Z-120726T0200Z/
HARDIN IA-HANCOCK IA-HAMILTON IA-FRANKLIN IA-CERRO GORDO IA-WRIGHT IA-
849 PM CDT WED JUL 25 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR EASTERN
WRIGHT...SOUTHERN CERRO GORDO...FRANKLIN...NORTHEASTERN HAMILTON...
SOUTHEASTERN HANCOCK AND NORTHERN HARDIN COUNTIES UNTIL 900 PM CDT...

AT 845 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF
60 MPH.  THIS STORM WAS LOCATED NEAR SHEFFIELD...OR 17 MILES SOUTH OF
MASON CITY...MOVING EAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  DOUGHERTY.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 137 AND 190.

ADDITIONAL LINE OF STORMS EXTENDS SOUTH OF WEBSTER CITY WILL MOVE 
NORTHEAST ACROSS HAMILTON COUNTY THROUGH 9 PM CDT...AND AN ANOTHER 
SEVERE THUNDERSTORM WARNING MAY BE NEEDED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE FOR DAMAGING WINDS...FALLING TREES AND FLYING DEBRIS. MOVE
INDOORS AND STAY AWAY FROM WINDOWS. IF YOU ARE IN A MOBILE HOME...GET
OUT NOW...AND SEEK SHELTER IN A REINFORCED BUILDING.

&&

LAT...LON 4247 9303 4247 9301 4236 9301 4236 9370
      4255 9370 4308 9350 4311 9302
TIME...MOT...LOC 0148Z 248DEG 29KT 4292 9311
WIND...HAIL 60MPH <.75IN

$$

JUNGBLUTH

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 25, 7:09 PM CDT	Severe Thunderstorm Warning	DMX	Humboldt, Pocahontas	51 min
Jul 25, 7:23 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Carroll, Greene, Sac	37 min
Jul 25, 7:29 PM CDT	Severe Thunderstorm Warning	DMX	Hancock, Wright	46 min
Jul 25, 8:02 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Calhoun, Greene, Hamilton, Webster	43 min
Jul 25, 8:22 PM CDT	Severe Thunderstorm Warning	DMX	Marshall	53 min
Jul 25, 8:39 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Hamilton, Hardin, Story, Webster	66 min
Jul 25, 9:04 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marion, Polk, Story, Warren	41 min
Jul 25, 9:10 PM CDT	Severe Thunderstorm Warning	DMX	Grundy, Hardin, Marshall, Story, Tama	50 min
Jul 25, 9:52 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk	33 min
Jul 25, 9:57 PM CDT	Severe Thunderstorm Warning	DMX	Poweshiek, Tama	34 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2012 Every 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.