Alert archive / Iowa / Tornado Warnings in 2010

Tornado Warning 21, NWS Sioux Falls, SD

June 25, 2010O'Brien County, Osceola County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Jun 25, 2010, 10:29 PM CDT for O'Brien County, Osceola County, Iowa. It was in force for 46 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 25, 2010, 10:29 PM CDT (03:29 UTC)
Expired: Jun 25, 2010, 11:15 PM CDT
In force: 46 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon

Counties O'Brien County, IA, Osceola County, IA

The radar

The Sioux Falls radar (KFSD), 97 km from the middle of the area, began a volume at 03:30 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 25, 10:45 PM CDT	TORNADO	3 Se Ashton, IA	BRIEF TOUCHDOWN

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 25, 3:35 PM CDT	Tornado Watch	SPC	8 hr
Jun 25, 9:06 PM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 3.5 hours before the alert went out and 220 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: 4115 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 1377 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 79 m²/s²
0-3 km storm-relative helicity: 274 m²/s²
Significant tornado parameter: 2.5
Supercell composite: 25.0

Open this sounding in Storm Lab

The text

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

398 
WFUS53 KFSD 260329
TORFSD
IAC141-143-260415-
/O.NEW.KFSD.TO.W.0021.100626T0329Z-100626T0415Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1029 PM CDT FRI JUN 25 2010

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN O'BRIEN COUNTY IN NORTHWEST IOWA...
  SOUTHWESTERN OSCEOLA COUNTY IN NORTHWEST IOWA...

* UNTIL 1115 PM CDT

* AT 1029 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE
  TRACKING A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS
  DANGEROUS STORM WAS LOCATED NEAR ASHTON...OR 20 MILES SOUTHEAST OF
  ROCK RAPIDS...AND MOVING SOUTHEAST AT 20 MPH.

* THIS TORNADIC STORM WILL BE NEAR...
  SANBORN AROUND 1100 PM CDT...

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 4325 9546 4308 9560 4320 9586 4332 9585
TIME...MOT...LOC 0329Z 305DEG 17KT 4328 9580

$$

RSR

2 follow-up statements

663 
WWUS53 KFSD 260358
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1058 PM CDT FRI JUN 25 2010

IAC143-260408-
/O.CAN.KFSD.TO.W.0021.000000T0000Z-100626T0415Z/
OSCEOLA IA-
1058 PM CDT FRI JUN 25 2010

...THE TORNADO WARNING FOR SOUTHWESTERN OSCEOLA COUNTY IS
CANCELLED...

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

LAT...LON 4308 9560 4320 9586 4326 9578 4326 9561
      4322 9549
TIME...MOT...LOC 0358Z 305DEG 17KT 4320 9565

$$

IAC141-260415-
/O.CON.KFSD.TO.W.0021.000000T0000Z-100626T0415Z/
O'BRIEN IA-
1058 PM CDT FRI JUN 25 2010

...A TORNADO WARNING REMAINS IN EFFECT FOR NORTHWESTERN O'BRIEN
COUNTY UNTIL 1115 PM CDT...

AT 1058 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE
TRACKING A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS
DANGEROUS STORM WAS LOCATED NEAR SANBORN...OR 24 MILES NORTHEAST OF
ORANGE CITY...MOVING SOUTHEAST AT 20 MPH.

THIS TORNADO WILL AFFECT MAINLY RURAL AREAS OF NORTHWESTERN O'BRIEN
COUNTY.

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 4308 9560 4320 9586 4326 9578 4326 9561
      4322 9549
TIME...MOT...LOC 0358Z 305DEG 17KT 4320 9565

$$

RSR

252 
WWUS53 KFSD 260417
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1117 PM CDT FRI JUN 25 2010

IAC141-260428-
/O.EXP.KFSD.TO.W.0021.000000T0000Z-100626T0415Z/
O'BRIEN IA-
1117 PM CDT FRI JUN 25 2010

...THE TORNADO WARNING FOR NORTHWESTERN O'BRIEN COUNTY HAS EXPIRED...

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

LAT...LON 4308 9560 4320 9586 4326 9578 4326 9561
      4322 9549
TIME...MOT...LOC 0358Z 305DEG 17KT 4320 9565

$$

RSR

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 25, 9:15 PM CDT	Severe Thunderstorm Warning	FSD	Dickinson, Osceola	45 min
Jun 25, 9:33 PM CDT	Severe Thunderstorm Warning	FSD	Lyon, Osceola	42 min
Jun 25, 9:53 PM CDT	Tornado Warning	FSD	Lyon, Osceola	37 min
Jun 25, 10:02 PM CDT	Severe Thunderstorm Warning	FSD	Clay, Dickinson, O'Brien, Osceola	43 min
Jun 25, 10:09 PM CDT	Tornado Warning	FSD	O'Brien, Osceola	36 min
Jun 25, 10:42 PM CDT	Tornado Warning	FSD	O'Brien, Sioux	48 min
Jun 25, 10:44 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista, Clay, O'Brien	46 min
Jun 25, 10:57 PM CDT	Flash Flood Warning	FSD	Clay, Dickinson, O'Brien, Osceola	3 hr
Jun 25, 11:14 PM CDT	Tornado Warning	FSD	O'Brien	46 min
Jun 25, 11:30 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista, Clay	45 min
Jun 25, 11:43 PM CDT	Tornado Warning	FSD	Cherokee, O'Brien, Plymouth, Sioux	47 min
Jun 26, 12:34 AM CDT	Tornado Warning	FSD	Buena Vista, Cherokee	41 min
Jun 26, 12:46 AM CDT	Severe Thunderstorm Warning	FSD	Buena Vista	44 min
Jun 26, 3:42 AM CDT	Flash Flood Watch	FSD	Buena Vista, Cherokee, Clay, Dickinson, Ida, Lyon and 3 more	24 hr

Nearby

Tornado Warnings in Iowa, 2010 Every tornado warning in 2010 Tornadoes in 2010

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.