Alert archive / Iowa / Tornado Warnings in 2009

Tornado Warning 4, NWS Des Moines, IA

June 7, 2009Dallas County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 7, 2009, 6:21 PM CDT for Dallas County, Iowa. It was in force for 24 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: Jun 7, 2009, 6:21 PM CDT (23:21 UTC)
Expired: Jun 7, 2009, 6:45 PM CDT
In force: 24 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon

County Dallas County, IA

The radar

The Des Moines radar (KDMX), 20 km from the middle of the area, began a volume at 23:23 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
Jun 7, 6:23 PM CDT	TSTM WND GST 70	Adel, IA	TREE DAMAGE IN ADEL WITH ESTIMATED 60-80 MPH WINDS
Jun 7, 6:23 PM CDT	TORNADO	3 S Dallas Center, IA	REPORTED AS RAIN WRAPPED BY A SPOTTER
Jun 7, 6:27 PM CDT	TSTM WND DMG	Adel, IA	AMATEUR RADIO OPERATOR REPORTED TREE DAMAGE IN ADEL WITH UP TO 10 INCH DIAMETER BRANCHES DOWN.
Jun 7, 6:34 PM CDT	HAIL 0.88	2 N Adel, IA
Jun 7, 6:40 PM CDT	TSTM WND DMG	4 S Dallas Center, IA	THREE TO FOUR INCH DIAMETER TREE BRANCHES DOWN. FROM KCCI TV CHASE VEHICLE.

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
Jun 7, 3:45 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.4 hours before the alert went out and 207 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: 83 J/kg
Mixed-layer CIN: -238 J/kg
Mixed-layer LCL: 460 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 318 m²/s²
0-3 km storm-relative helicity: 238 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.2

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDMX 072321
TORDMX
IAC049-072345-
/O.NEW.KDMX.TO.W.0004.090607T2321Z-090607T2345Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
621 PM CDT SUN JUN 7 2009

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL DALLAS COUNTY IN CENTRAL IOWA...

* UNTIL 645 PM CDT

* AT 620 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR ADEL...OR 23 MILES WEST OF DES MOINES...AND
  MOVING EAST AT 30 MPH.

* THIS TORNADIC STORM WILL BE NEAR...
  DALLAS CENTER BY 630 PM CDT...
  WAUKEE BY 640 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A HAZARDOUS SITUATION. SEEK SHELTER IN A BASEMENT...OR IN AN
INTERIOR ROOM. STAY AWAY FROM WINDOWS. IF YOU ARE OUTSIDE OR IN A
CAR...SEEK SHELTER IN A REINFORCED BUILDING.

&&

LAT...LON 4165 9410 4174 9382 4167 9382 4160 9382
      4159 9381 4158 9381 4156 9409
TIME...MOT...LOC 2322Z 249DEG 26KT 4162 9405

$$

MOYER

2 follow-up statements

000 
WWUS53 KDMX 072331
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
631 PM CDT SUN JUN 7 2009

IAC049-072345-
/O.CON.KDMX.TO.W.0004.000000T0000Z-090607T2345Z/
DALLAS IA-
631 PM CDT SUN JUN 7 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 645 PM CDT FOR EASTERN
DALLAS COUNTY...

AT 630 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A TORNADO. THIS TORNADO WAS LOCATED JUST SOUTH OF DALLAS 
CENTER...OR 20 MILES WEST OF DES MOINES...MOVING EAST AT 25 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. TAKE COVER NOW IF YOU WAIT
TO SEE OR HEAR IT COMING...IT MAY BE TOO LATE TO GET TO A SAFE PLACE.

REPORT TORNADOES...WIND IN EXCESS OF 50 MPH...HAIL LARGER THAN ONE
HALF INCH...OR STORM DAMAGE BY CALLING LOCAL LAW ENFORCEMENT AND
ASKING THEM TO RELAY THE REPORT TO THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4167 9404 4174 9382 4167 9382 4162 9382
      4159 9400
TIME...MOT...LOC 2331Z 251DEG 22KT 4163 9398

$$

MOYER

000 
WWUS53 KDMX 072348
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
648 PM CDT SUN JUN 7 2009

IAC049-072358-
/O.EXP.KDMX.TO.W.0004.000000T0000Z-090607T2345Z/
DALLAS IA-
648 PM CDT SUN JUN 7 2009

...THE TORNADO WARNING FOR EASTERN DALLAS COUNTY EXPIRES AT 645 PM
CDT...

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

REPORT TORNADOES...WIND IN EXCESS OF 50 MPH...HAIL LARGER THAN ONE
HALF INCH...OR STORM DAMAGE BY CALLING LOCAL LAW ENFORCEMENT AND
ASKING THEM TO RELAY THE REPORT TO THE NATIONAL WEATHER SERVICE.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 11 PM CDT.

LAT...LON 4167 9404 4174 9382 4167 9382 4162 9382
      4159 9400
TIME...MOT...LOC 2331Z 251DEG 22KT 4163 9398

$$

MOYER

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 7, 12:50 AM CDT	Severe Thunderstorm Warning	DMX	Cass	39 min
Jun 7, 1:12 AM CDT	Severe Thunderstorm Warning	DMX	Adair	48 min
Jun 7, 4:54 PM CDT	Severe Thunderstorm Warning	DMX	Audubon, Cass	49 min
Jun 7, 5:29 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Guthrie	46 min
Jun 7, 5:58 PM CDT	Severe Thunderstorm Warning	DMX	Dallas	47 min
Jun 7, 6:11 PM CDT	Areal Flood Advisory	DMX	Adair, Dallas, Guthrie	107 min
Jun 7, 6:42 PM CDT	Tornado Warning	DMX	Polk	33 min
Jun 7, 6:45 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Polk	45 min
Jun 7, 6:53 PM CDT	Areal Flood Advisory	DMX	Polk, Story	3 hr

Nearby

Tornado Warnings in Iowa, 2009 Every tornado warning in 2009 Tornadoes in 2009

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.