Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 21, NWS Des Moines, IA

April 14, 20125 counties in Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Apr 14, 2012, 7:37 PM CDT for 5 counties in Iowa. It was in force for 38 min. 6 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: Apr 14, 2012, 7:37 PM CDT (00:37 UTC)
Expired: Apr 14, 2012, 8:15 PM CDT
In force: 38 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Boone County, IA, Dallas County, IA, Jasper County, IA, Polk County, IA, Story County, IA

The radar

The Des Moines radar (KDMX), 14 km from the middle of the area, began a volume at 00:37 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
Apr 14, 7:39 PM CDT	TSTM WND GST 70	4 S Dallas Center, IA
Apr 14, 7:45 PM CDT	TSTM WND DMG	4 S Dallas Center, IA	12-13 TREE SNAPPED AT BASE.
Apr 14, 7:50 PM CDT	TSTM WND DMG	2 S Johnston, IA	SMALL TREE BLOWN OVER. TIME ESTIMATED FROM RADAR.
Apr 14, 7:55 PM CDT	TSTM WND GST 65	2 Nnw Ankeny Airport, IA	60 TO 65 MPH WINDS...NO DAMAGE REPORTS YET. WIND LASTED ABOUT 10 MPH.
Apr 14, 7:59 PM CDT	TSTM WND DMG	1 Ese Johnston, IA	SMALL BRANCHES BROKEN OFF. MINOR STREET FLOODING.
Apr 14, 8:02 PM CDT	TSTM WND GST 60	2 Ene Urbandale, IA

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
Apr 14, 5:00 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 0.6 hours before the alert went out and 238 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 871 m above ground
0-6 km bulk shear: 73 kt
0-1 km storm-relative helicity: 276 m²/s²
0-3 km storm-relative helicity: 483 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

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

033 
WUUS53 KDMX 150037
SVRDMX
IAC015-049-099-153-169-150115-
/O.NEW.KDMX.SV.W.0021.120415T0037Z-120415T0115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
737 PM CDT SAT APR 14 2012

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN BOONE COUNTY IN CENTRAL IOWA...
  EASTERN DALLAS COUNTY IN CENTRAL IOWA...
  NORTHWESTERN JASPER COUNTY IN CENTRAL IOWA...
  NORTHERN POLK COUNTY IN CENTRAL IOWA...
  SOUTHERN STORY COUNTY IN CENTRAL IOWA...

* UNTIL 815 PM CDT

* AT 732 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 PERRY TO WAUKEE...AND MOVING
  EAST AT 55 MPH.

* LOCATIONS IMPACTED INCLUDE...
  WOODWARD...GRIMES...CLIVE...URBANDALE...MADRID...JOHNSTON...POLK
  CITY...ANKENY...HUXLEY...GRANGER...SAYLORVILLE LAKE...
  SAYLORVILLE...SHELDAHL...SLATER...ALLEMAN...ANKENY AIRPORT...
  ELKHART...CAMBRIDGE...MAXWELL AND VALERIA.

THIS INCLUDES INTERSTATE 80 BETWEEN MILE MARKERS 125 AND 134.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 88 AND 108.

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...
SEEK SHELTER IN A REINFORCED BUILDING.

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. SEVERE
THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE OR NO WARNING. IF A
TORNADO IS SPOTTED...IMMEDIATELY MOVE TO THE BASEMENT OR SMALL
INTERIOR ROOM OF A REINFORCED BUILDING.

&&

LAT...LON 4154 9401 4188 9409 4201 9323 4187 9323
      4186 9322 4175 9321
TIME...MOT...LOC 0037Z 248DEG 46KT 4193 9399 4160 9386
WIND...HAIL 60MPH 1.00IN

$$

COGIL

2 follow-up statements

331 
WWUS53 KDMX 150053
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
753 PM CDT SAT APR 14 2012

IAC015-049-099-153-169-150115-
/O.CON.KDMX.SV.W.0021.000000T0000Z-120415T0115Z/
STORY IA-POLK IA-JASPER IA-BOONE IA-DALLAS IA-
753 PM CDT SAT APR 14 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR EASTERN
DALLAS...SOUTHEASTERN BOONE...NORTHWESTERN JASPER...NORTHERN POLK AND
SOUTHERN STORY COUNTIES UNTIL 815 PM CDT...

AT 751 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 MADRID TO JOHNSTON TO
URBANDALE...MOVING EAST AT 40 MPH.

LOCATIONS IMPACTED INCLUDE...
  ANKENY...HUXLEY...BONDURANT...SHELDAHL...SAYLORVILLE...SLATER...
  ALLEMAN...ANKENY AIRPORT...ELKHART...CAMBRIDGE...MAXWELL...
  VALERIA...MINGO AND COLLINS.

THIS INCLUDES INTERSTATE 80 BETWEEN MILE MARKERS 125 AND 134.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 88 AND 108.

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.

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. IF A TORNADO
IS SPOTTED... IMMEDIATELY MOVE TO THE BASEMENT OR SMALL INTERIOR ROOM
OF A REINFORCED BUILDING.

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

&&

LAT...LON 4154 9401 4188 9409 4201 9323 4187 9323
      4186 9322 4175 9321
TIME...MOT...LOC 0053Z 248DEG 36KT 4193 9381 4173 9369
          4165 9370
WIND...HAIL 60MPH 1.00IN

$$

COGIL

228 
WWUS53 KDMX 150116
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
816 PM CDT SAT APR 14 2012

IAC015-049-099-153-169-150126-
/O.EXP.KDMX.SV.W.0021.000000T0000Z-120415T0115Z/
STORY IA-POLK IA-JASPER IA-BOONE IA-DALLAS IA-
816 PM CDT SAT APR 14 2012

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN DALLAS...SOUTHEASTERN
BOONE...NORTHWESTERN JASPER...NORTHERN POLK AND SOUTHERN STORY
COUNTIES HAS EXPIRED...

THE LINE OF STORMS WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE
WARNED AREA.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 1200 AM CDT.

LAT...LON 4154 9401 4188 9409 4201 9323 4187 9323
      4186 9322 4175 9321
TIME...MOT...LOC 0053Z 248DEG 36KT 4193 9381 4173 9369
          4165 9370

$$

COGIL

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 14, 7:07 PM CDT	Flash Flood Warning	DMX	Adair, Madison	101 min
Apr 14, 7:11 PM CDT	Tornado Warning	DMX	Madison, Union	19 min
Apr 14, 7:26 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas, Madison, Marion, Union, Warren	49 min
Apr 14, 7:30 PM CDT	Flash Flood Warning	DMX	Adair, Dallas, Guthrie, Madison, Polk, Warren	3 hr
Apr 14, 7:32 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Jasper, Madison, Marion, Polk, Warren	43 min
Apr 14, 7:37 PM CDT	Tornado Warning	DMX	Clarke, Madison, Warren	23 min
Apr 14, 8:10 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marshall, Polk, Story	50 min
Apr 14, 8:14 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas, Mahaska, Marion, Monroe, Warren	46 min
Apr 14, 8:33 PM CDT	Severe Thunderstorm Warning	DMX	Poweshiek, Tama	57 min
Apr 14, 8:43 PM CDT	Flash Flood Warning	DMX	Marshall, Tama	84 min
Apr 14, 8:55 PM CDT	Flash Flood Warning	DMX	Clarke, Decatur, Lucas, Marion, Monroe, Ringgold and 2 more	103 min
Apr 14, 8:56 PM CDT	Severe Thunderstorm Warning	DMX	Lucas, Mahaska, Marion, Monroe, Wapello	49 min
Apr 14, 9:21 PM CDT	Tornado Warning	DMX	Mahaska	24 min
Apr 14, 9:42 PM CDT	Severe Thunderstorm Warning	DMX	Wapello	16 min
Apr 14, 10:25 PM CDT	Flash Flood Watch	DMX	Adair, Adams, Audubon, Cass, Clarke, Dallas and 7 more	7 hr
Apr 15, 4:15 AM CDT	High Wind Warning	DMX	Adair, Adams, Audubon, Boone, Calhoun, Carroll and 19 more	16 hr
Apr 15, 4:15 AM CDT	Wind Advisory	DMX	Appanoose, Black Hawk, Boone, Bremer, Butler, Calhoun and 29 more	33 hr

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.