Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 178, NWS Des Moines, IA

September 7, 2012Boone County, Greene County, Story County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Sep 7, 2012, 1:20 AM CDT for Boone County, Greene County, Story County, Iowa. It was in force for 40 min. 5 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
Sep 7, 2012, 1:20 AM CDT (06:20 UTC)
Expired
Sep 7, 2012, 2:00 AM CDT
In force
40 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Boone County, IA, Greene County, IA, Story County, IA

What was reported inside it

TimeReportWhereRemark
Sep 7, 1:28 AM CDTHAIL 1.752 S Boxholm, IAEMERGENCY MANAGER REPORTS PING PONG TO GOLF BALL HAIL.
Sep 7, 1:32 AM CDTHAIL 0.88Boxholm, IA10 MINUTES OF PEA TO NICKEL HAIL.
Sep 7, 1:44 AM CDTHAIL 1.53 Sw Fraser, IA
Sep 7, 1:50 AM CDTHAIL 0.88Boone, IA
Sep 7, 2:00 AM CDTHAIL 13 Sse Boone Airport, IAMINOR CAR DAMAGE NOTED. QUARTER SIZE HAIL WAS THE LARGEST OBSERVED...BUT MAY HAVE BEEN LARGER. TIME ESTIMATED FROM RADAR.

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, 6.3 hours before the alert went out and 234 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 2012-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 275 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 2012-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 140 square meters per square second.1939587897Sfc1 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
275 J/kg
Mixed-layer CIN
-320 J/kg
Mixed-layer LCL
2527 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
140 m²/s²
0-3 km storm-relative helicity
305 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

554 
WUUS53 KDMX 070620
SVRDMX
IAC015-073-169-070700-
/O.NEW.KDMX.SV.W.0178.120907T0620Z-120907T0700Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
120 AM CDT FRI SEP 7 2012

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BOONE COUNTY IN CENTRAL IOWA...
  NORTHEASTERN GREENE COUNTY IN WEST CENTRAL IOWA...
  SOUTHWESTERN STORY COUNTY IN CENTRAL IOWA...

* UNTIL 200 AM CDT

* AT 116 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 9 MILES
  NORTHWEST OF OGDEN...OR 25 MILES SOUTH OF FORT DODGE...AND MOVING
  SOUTHEAST AT 55 MPH.

* LOCATIONS IMPACTED INCLUDE...
  AMES...OGDEN...BOONE...MADRID...HUXLEY...PILOT MOUND...FRASER...
  BOONE AIRPORT...LUTHER...GILBERT...KELLEY...AMES AIRPORT...
  SLATER...SHELDAHL...CAMBRIDGE AND MAXWELL.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 103 AND 117.

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.

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...DEADLY CLOUD TO GROUND
LIGHTNING IS OCCURRING CONTINUOUSLY WITH THIS STORM.

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS. TURN AROUND DON/T DROWN.

&&

LAT...LON 4187 9327 4186 9397 4221 9434 4221 9371
TIME...MOT...LOC 0620Z 304DEG 47KT 4211 9409
WIND...HAIL 60MPH 1.00IN

$$

SKOW
2 follow-up statements
369 
WWUS53 KDMX 070631
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
131 AM CDT FRI SEP 7 2012

IAC073-070641-
/O.CAN.KDMX.SV.W.0178.000000T0000Z-120907T0700Z/
GREENE IA-
131 AM CDT FRI SEP 7 2012

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

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

LAT...LON 4221 9416 4221 9371 4187 9327 4187 9385
      4204 9416
TIME...MOT...LOC 0631Z 287DEG 29KT 4213 9404

$$

IAC015-169-070700-
/O.CON.KDMX.SV.W.0178.000000T0000Z-120907T0700Z/
STORY IA-BOONE IA-
131 AM CDT FRI SEP 7 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR BOONE AND
SOUTHWESTERN STORY COUNTIES UNTIL 200 AM CDT...

AT 126 AM CDT...EMERGENCY MANAGEMENT REPORTED A SEVERE THUNDERSTORM
PRODUCING GOLF BALL SIZE HAIL.  THIS STORM WAS LOCATED 8 MILES
NORTHWEST OF OGDEN...OR 25 MILES WEST OF AMES...MOVING EAST AT 35
MPH.

LOCATIONS IMPACTED INCLUDE...
  AMES...OGDEN...BOONE...MADRID...HUXLEY...FRASER...BOONE AIRPORT...
  LUTHER...GILBERT...AMES AIRPORT...KELLEY...SLATER...CAMBRIDGE AND
  MAXWELL.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 103 AND 117.

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 4221 9416 4221 9371 4187 9327 4187 9385
      4204 9416
TIME...MOT...LOC 0631Z 287DEG 29KT 4213 9404
WIND...HAIL <50MPH 1.75IN

$$

SKOW
242 
WWUS53 KDMX 070651
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
151 AM CDT FRI SEP 7 2012

IAC015-169-070700-
/O.CON.KDMX.SV.W.0178.000000T0000Z-120907T0700Z/
STORY IA-BOONE IA-
151 AM CDT FRI SEP 7 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR BOONE AND
SOUTHWESTERN STORY COUNTIES UNTIL 200 AM CDT...

AT 149 AM CDT...EMERGENCY MANAGEMENT REPORTED A SEVERE THUNDERSTORM
PRODUCING QUARTER SIZE HAIL.  THIS STORM WAS LOCATED NEAR BOONE...OR
12 MILES WEST OF AMES...MOVING EAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  AMES...MADRID...HUXLEY...LUTHER...GILBERT...AMES AIRPORT...
  KELLEY...SLATER...CAMBRIDGE AND MAXWELL.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 103 AND 117.

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 4200 9409 4221 9395 4221 9371 4187 9327
      4187 9385
TIME...MOT...LOC 0651Z 287DEG 29KT 4207 9384
WIND...HAIL <50MPH 1.00IN

$$

SKOW

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 6, 10:42 PM CDTSevere Thunderstorm WarningDMXCalhoun, Pocahontas, Sac48 min
Sep 6, 11:15 PM CDTSevere Thunderstorm WarningDMXCalhoun, Carroll, Greene, Webster45 min
Sep 6, 11:53 PM CDTSevere Thunderstorm WarningDMXCalhoun, Greene27 min
Sep 7, 1:45 AM CDTSevere Thunderstorm WarningDMXJasper, Marshall, Poweshiek, Tama45 min
Sep 7, 1:48 AM CDTSevere Thunderstorm WarningDMXCalhoun, Pocahontas, Sac, Webster42 min
Sep 7, 1:58 AM CDTSevere Thunderstorm WarningDMXBoone, Polk, Story47 min
Sep 7, 3:05 AM CDTSevere Thunderstorm WarningDMXBoone, Hamilton, Story, Webster40 min
Sep 7, 3:25 AM CDTSevere Thunderstorm WarningDMXJasper, Mahaska, Poweshiek50 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.