Alert archive / Iowa / Tornado Warnings in 2011

Tornado Warning 3, NWS Omaha, NE

March 22, 2011Harrison County, Iowa

NWS Omaha, NE issued this tornado warning at Mar 22, 2011, 4:53 PM CDT for Harrison County, Iowa. It was in force for 37 min. 3 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: Mar 22, 2011, 4:53 PM CDT (21:53 UTC)
Expired: Mar 22, 2011, 5:30 PM CDT
In force: 37 min
Issued by: NWS Omaha, NE
Area: Storm-based polygon

County Harrison County, IA

The radar

The Omaha radar (KOAX), 47 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

Time	Report	Where	Remark
Mar 22, 5:00 PM CDT	TORNADO	2 E Missouri Valley, IA
Mar 22, 5:03 PM CDT	HAIL 1	1 Ne Missouri Valley, IA	WALL CLOUD SPOTTED WITH STORM.
Mar 22, 5:20 PM CDT	HAIL 1	Woodbine, 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
Mar 22, 2:03 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.9 hours before the alert went out and 47 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: 486 J/kg
Mixed-layer CIN: -475 J/kg
Mixed-layer LCL: 777 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 477 m²/s²
0-3 km storm-relative helicity: 501 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

586 
WFUS53 KOAX 222153
TOROAX
IAC085-222230-
/O.NEW.KOAX.TO.W.0003.110322T2153Z-110322T2230Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
453 PM CDT TUE MAR 22 2011

THE NATIONAL WEATHER SERVICE IN OMAHA HAS ISSUED A

* TORNADO WARNING FOR...
  HARRISON COUNTY IN SOUTHWEST IOWA...

* UNTIL 530 PM CDT

* AT 450 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A FUNNEL CLOUD
  NEAR MISSOURI VALLEY...OR 19 MILES NORTH OF OMAHA. A TORNADO MAY
  DEVELOP AT ANY TIME! DOPPLER RADAR SHOWED THIS TORNADIC STORM
  MOVING NORTHEAST AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MODALE...MISSOURI VALLEY...LOGAN...MAGNOLIA...WOODBINE AND DUNLAP.

THE WARNED AREA INCLUDES INTERSTATE 29 IN IOWA BETWEEN MILE MARKERS
74 AND 82.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4150 9587 4151 9598 4151 9599 4154 9600
      4155 9601 4154 9603 4153 9603 4154 9608
      4186 9584 4186 9556
TIME...MOT...LOC 2153Z 215DEG 34KT 4156 9595

$$

FOBERT

1 follow-up statement

588 
WWUS53 KOAX 222201
SVSOAX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
501 PM CDT TUE MAR 22 2011

IAC085-222230-
/O.CON.KOAX.TO.W.0003.000000T0000Z-110322T2230Z/
HARRISON IA-
501 PM CDT TUE MAR 22 2011

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

AT 500 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A TORNADO 2 MILES 
EAST OF MISSOURI VALLEY...OR 24 MILES NORTH OF OMAHA...MOVING 
NORTHEAST AT 50 MPH.

LOCATIONS IMPACTED INCLUDE...
  LOGAN...MAGNOLIA...WOODBINE AND DUNLAP.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPEAT...A TORNADO IS ON THE GROUND. TAKE COVER NOW. MOVE TO AN
INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING. AVOID
WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR OUTDOORS...MOVE TO THE
CLOSEST SUBSTANTIAL SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4150 9587 4151 9598 4151 9599 4154 9600
      4155 9601 4154 9603 4153 9603 4154 9608
      4186 9584 4186 9556
TIME...MOT...LOC 2201Z 235DEG 29KT 4159 9584

$$

FOBERT

The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 22, 4:10 PM CDT	Severe Thunderstorm Warning	OAX	Fremont, Mills	50 min
Mar 22, 4:48 PM CDT	Severe Thunderstorm Warning	OAX	Harrison	42 min
Mar 22, 4:57 PM CDT	Severe Thunderstorm Warning	OAX	Montgomery, Pottawattamie	33 min
Mar 22, 5:03 PM CDT	Tornado Warning	OAX	Harrison, Pottawattamie	27 min
Mar 22, 5:08 PM CDT	Tornado Warning	OAX	Montgomery	22 min
Mar 22, 5:19 PM CDT	Tornado Warning	OAX	Shelby	26 min
Mar 22, 5:31 PM CDT	Tornado Warning	OAX	Harrison, Shelby	29 min

Nearby

Tornado Warnings in Iowa, 2011 Every tornado warning in 2011 Tornadoes in 2011

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.