Alert archive / Iowa / Tornado Warnings in 2015

Tornado Warning 32, NWS Sioux Falls, SD

October 23, 2015Cherokee County, O'Brien County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Oct 23, 2015, 6:16 PM CDT for Cherokee County, O'Brien County, Iowa. It was in force for 29 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: Oct 23, 2015, 6:16 PM CDT (23:16 UTC)
Expired: Oct 23, 2015, 6:45 PM CDT
In force: 29 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

Counties Cherokee County, IA, O'Brien County, IA

The radar

The Sioux Falls radar (KFSD), 124 km from the middle of the area, began a volume at 23:16 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
Oct 23, 6:39 PM CDT	TORNADO	2 N Larrabee, IA	TORNADO LIFTS ROOF OFF HOUSE

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.3 hours before the alert went out and 190 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: 28 J/kg
Mixed-layer CIN: -74 J/kg
Mixed-layer LCL: 554 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 240 m²/s²
0-3 km storm-relative helicity: 233 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.

830 
WFUS53 KFSD 232316
TORFSD
IAC035-141-232345-
/O.NEW.KFSD.TO.W.0032.151023T2316Z-151023T2345Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
616 PM CDT FRI OCT 23 2015

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  NORTH CENTRAL CHEROKEE COUNTY IN NORTHWESTERN IOWA...
  SOUTHEASTERN O'BRIEN COUNTY IN NORTHWESTERN IOWA...

* UNTIL 645 PM CDT
    
* AT 616 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED OVER LARRABEE...OR NEAR CHEROKEE...MOVING
  NORTHEAST AT 25 MPH.

  HAZARD...TORNADO. 

  SOURCE...RADAR INDICATED ROTATION. 

  IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WITHOUT 
           SHELTER. MOBILE HOMES WILL BE DAMAGED OR DESTROYED. 
           DAMAGE TO ROOFS...WINDOWS AND VEHICLES WILL OCCUR.  TREE 
           DAMAGE IS LIKELY. 

* THIS DANGEROUS STORM WILL BE NEAR...
  LARRABEE AROUND 625 PM CDT.
  SUTHERLAND AROUND 640 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS TORNADIC THUNDERSTORM INCLUDE
CALUMET.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4278 9557 4282 9568 4306 9550 4306 9539
      4292 9539
TIME...MOT...LOC 2316Z 218DEG 21KT 4284 9559 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

WEISSER

1 follow-up statement

681 
WWUS53 KFSD 232329
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
629 PM CDT FRI OCT 23 2015

IAC035-141-232345-
/O.CON.KFSD.TO.W.0032.000000T0000Z-151023T2345Z/
CHEROKEE IA-O'BRIEN IA-
629 PM CDT FRI OCT 23 2015

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 645 PM CDT FOR NORTH
CENTRAL CHEROKEE AND SOUTHEASTERN O'BRIEN COUNTIES...
    
AT 627 PM CDT...A CONFIRMED TORNADO WAS LOCATED OVER LARRABEE...OR 9
MILES NORTH OF CHEROKEE...MOVING NORTHEAST AT 25 MPH.

HAZARD...DAMAGING TORNADO. 

SOURCE...LAW ENFORCEMENT CONFIRMED TORNADO. 

IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WITHOUT 
         SHELTER. MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE 
         TO ROOFS...WINDOWS AND VEHICLES WILL OCCUR.  TREE DAMAGE IS 
         LIKELY. 

THIS TORNADO WILL BE NEAR...
  SUTHERLAND AROUND 645 PM CDT.

AT 626 PM CDT...A TORNADO WAS REPORTED 2 MILES SOUTHWEST OF LARRABEE.

OTHER LOCATIONS IMPACTED BY THIS TORNADIC THUNDERSTORM INCLUDE
CALUMET.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4278 9557 4282 9568 4306 9550 4306 9539
      4292 9539
TIME...MOT...LOC 2327Z 217DEG 20KT 4288 9555 

TORNADO...OBSERVED
HAIL...<.75IN

$$

WEISSER

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 23, 5:43 PM CDT	Tornado Warning Tornado observed	FSD	Sioux	32 min
Oct 23, 5:45 PM CDT	Tornado Warning	FSD	Cherokee	30 min
Oct 23, 5:47 PM CDT	Tornado Warning	FSD	Plymouth	28 min
Oct 23, 6:08 PM CDT	Tornado Warning Tornado observed	FSD	O'Brien	37 min
Oct 23, 6:12 PM CDT	Tornado Warning	FSD	Plymouth, Sioux	33 min
Oct 23, 6:42 PM CDT	Tornado Warning Tornado observed	FSD	O'Brien	14 min
Oct 23, 6:44 PM CDT	Tornado Warning	FSD	O'Brien, Osceola	31 min

Nearby

Tornado Warnings in Iowa, 2015 Every tornado warning in 2015 Tornadoes in 2015

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.