Alert archive / Iowa / Tornado Warnings in 2016

Tornado Warning 11, NWS Sioux Falls, SD

July 7, 2016Sioux County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Jul 7, 2016, 3:25 PM CDT for Sioux County, Iowa. It was in force for 16 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 7, 2016, 3:25 PM CDT (20:25 UTC)
Expired
Jul 7, 2016, 3:41 PM CDT
In force
16 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Sioux County, IA

The radar

The Sioux Falls radar (KFSD), 75 km from the middle of the area, began a volume at 20:29 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.

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 8.4 hours before the alert went out and 205 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 2016-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 7 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 2016-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -269 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
7 J/kg
Mixed-layer CIN
-552 J/kg
Mixed-layer LCL
778 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
-269 m²/s²
0-3 km storm-relative helicity
-234 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

416 
WFUS53 KFSD 072025
TORFSD
IAC167-072100-
/O.NEW.KFSD.TO.W.0011.160707T2025Z-160707T2100Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
325 PM CDT THU JUL 7 2016

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHEASTERN SIOUX COUNTY IN NORTHWESTERN IOWA...

* UNTIL 400 PM CDT
    
* AT 325 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED JUST SOUTHEAST OF HULL...OR NORTHEAST OF SIOUX
  CENTER...MOVING EAST 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...
  BOYDEN AROUND 335 PM CDT. 

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 4311 9613 4316 9612 4325 9587 4309 9587
TIME...MOT...LOC 2025Z 263DEG 20KT 4314 9608 

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

$$

CHAPMAN
1 follow-up statement
773 
WWUS53 KFSD 072041
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
341 PM CDT THU JUL 7 2016

IAC167-072051-
/O.CAN.KFSD.TO.W.0011.000000T0000Z-160707T2100Z/
SIOUX IA-
341 PM CDT THU JUL 7 2016

...THE TORNADO WARNING FOR NORTHEASTERN SIOUX COUNTY IS CANCELLED...
                
THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER APPEARS CAPABLE OF PRODUCING A TORNADO.
THEREFORE...THE WARNING HAS BEEN CANCELLED.  HOWEVER GUSTY WINDS ARE
STILL POSSIBLE WITH THIS THUNDERSTORM.

LAT...LON 4311 9613 4316 9612 4325 9587 4309 9587
TIME...MOT...LOC 2039Z 263DEG 20KT 4315 9596 

$$

CHAPMAN

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 6, 11:52 PM CDTSevere Thunderstorm WarningFSDBuena Vista, Cherokee, Clay, O'Brien38 min
Jul 7, 12:08 AM CDTSevere Thunderstorm WarningFSDIda, Woodbury52 min

Nearby

Tornado Warnings in Iowa, 2016Every tornado warning in 2016Tornadoes in 2016

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.