Alert archive / Iowa / Tornado Warnings in 2009

Tornado Warning 9, NWS Des Moines, IA

June 21, 2009Hamilton County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 21, 2009, 4:56 PM CDT for Hamilton County, Iowa. It was in force for 34 min. 1 report 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 21, 2009, 4:56 PM CDT (21:56 UTC)
Expired
Jun 21, 2009, 5:30 PM CDT
In force
34 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon

County Hamilton County, IA

The radar

The Des Moines radar (KDMX), 83 km from the middle of the area, began a volume at 21:55 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
Jun 21, 5:35 PM CDTTORNADO3 Se Williams, IABRIEF TORNADO...NO DAMAGE. DELAYED REPORT.

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.

IssuedProductOfficeLasted
Jun 21, 3:17 PM CDTTornado WatchSPC8 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.9 hours before the alert went out and 262 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 12:00Z on 2009-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 564 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 12:00Z on 2009-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 228 square meters per square second.19395878Sfc1 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
564 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
482 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
228 m²/s²
0-3 km storm-relative helicity
210 m²/s²
Significant tornado parameter
0.4
Supercell composite
3.1

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDMX 212156
TORDMX
IAC079-212230-
/O.NEW.KDMX.TO.W.0009.090621T2156Z-090621T2230Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
456 PM CDT SUN JUN 21 2009

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHEASTERN HAMILTON COUNTY IN CENTRAL IOWA...

* UNTIL 530 PM CDT

* AT 456 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED 7 MILES EAST OF WEBSTER CITY...OR 25 MILES EAST
  OF FORT DODGE...AND MOVING NORTHEAST AT 15 MPH.

* THIS TORNADIC STORM WILL BE NEAR...
  BLAIRSBURG BY 515 PM CDT...
  WILLIAMS BY 530 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 4244 9347 4237 9373 4245 9380 4256 9363
      4256 9355
TIME...MOT...LOC 2157Z 234DEG 11KT 4243 9369

$$

COGIL
3 follow-up statements
000 
WWUS53 KDMX 212202
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
502 PM CDT SUN JUN 21 2009

IAC079-212230-
/O.CON.KDMX.TO.W.0009.000000T0000Z-090621T2230Z/
HAMILTON IA-
502 PM CDT SUN JUN 21 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 530 PM CDT FOR
NORTHEASTERN HAMILTON COUNTY...

AT 501 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A FUNNEL CLOUD.
THIS TORNADO WAS LOCATED NEAR BLAIRSBURG...OR 26 MILES EAST OF FORT
DODGE...MOVING NORTHEAST AT 15 MPH.

THE TORNADO WILL BE NEAR...
  BLAIRSBURG BY 515 PM CDT...
  WILLIAMS BY 530 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4244 9347 4237 9373 4245 9380 4256 9363
      4256 9355
TIME...MOT...LOC 2202Z 234DEG 11KT 4244 9367

$$

COGIL
000 
WWUS53 KDMX 212219
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
519 PM CDT SUN JUN 21 2009

IAC079-212230-
/O.CON.KDMX.TO.W.0009.000000T0000Z-090621T2230Z/
HAMILTON IA-
519 PM CDT SUN JUN 21 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 530 PM CDT FOR
NORTHEASTERN HAMILTON COUNTY...

AT 515 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A TORNADO. THIS TORNADO WAS LOCATED NEAR BLAIRSBURG...OR 28
MILES EAST OF FORT DODGE...MOVING NORTHEAST AT 20 MPH.

THE TORNADO WILL BE NEAR...
  WILLIAMS BY 530 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4244 9347 4237 9373 4245 9380 4256 9363
      4256 9355
TIME...MOT...LOC 2219Z 237DEG 16KT 4246 9361

$$

COGIL
000 
WWUS53 KDMX 212231
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
531 PM CDT SUN JUN 21 2009

IAC079-212241-
/O.EXP.KDMX.TO.W.0009.000000T0000Z-090621T2230Z/
HAMILTON IA-
531 PM CDT SUN JUN 21 2009

...THE TORNADO WARNING FOR NORTHEASTERN HAMILTON COUNTY EXPIRES AT
530 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED SLIGHTLY AND NO 
LONGER APPEARS CAPABLE OF PRODUCING A TORNADO AT THIS TIME. 

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 10 PM CDT.

LAT...LON 4244 9347 4237 9373 4245 9380 4256 9363
      4256 9355
TIME...MOT...LOC 2219Z 237DEG 16KT 4246 9361

$$

COGIL

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 3:41 PM CDTHeat AdvisoryDMXAdair, Adams, Appanoose, Audubon, Black Hawk, Boone and 45 more66 hr
Jun 21, 5:35 PM CDTTornado WarningDMXHamilton, Hardin25 min
Jun 21, 5:50 PM CDTTornado WarningDMXFranklin, Hardin25 min
Jun 21, 6:12 PM CDTTornado WarningDMXHardin33 min
Jun 21, 6:41 PM CDTTornado WarningDMXButler, Grundy, Hardin34 min

Nearby

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