Alert archive / Nebraska / Tornado Warnings in 2017

Tornado Warning 19, NWS Sioux Falls, SD

June 29, 2017Dakota County, Nebraska; Woodbury County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Jun 29, 2017, 4:23 PM CDT for Dakota County, Nebraska; Woodbury County, Iowa. It was in force for 37 min. 5 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: Jun 29, 2017, 4:23 PM CDT (21:23 UTC)
Expired: Jun 29, 2017, 5:00 PM CDT
In force: 37 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

Counties Woodbury County, IA, Dakota County, NE

The radar

The Omaha radar (KOAX), 122 km from the middle of the area, began a volume at 21:26 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 29, 4:27 PM CDT	HAIL 1.25	2 Wsw South Sioux City, NE	ALSO SEVERAL TREE BRANCHES DOWN.
Jun 29, 4:30 PM CDT	TSTM WND GST 65	1 Se South Sioux City, NE
Jun 29, 4:30 PM CDT	HAIL 4.25	2 N Sergeant Bluff, IA
Jun 29, 4:33 PM CDT	TSTM WND GST 60	2 W Sergeant Bluff, IA
Jun 29, 4:35 PM CDT	FUNNEL CLOUD	2 W Sergeant Bluff, IA	REPORTED BY FAA PERSONNEL AT SIOUX CITY GATEWAY AIRPORT.

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 29, 3:42 PM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.4 hours before the alert went out and 122 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: 712 J/kg
Mixed-layer CIN: -119 J/kg
Mixed-layer LCL: 1324 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: -19 m²/s²
0-3 km storm-relative helicity: 9 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

780 
WFUS53 KFSD 292123
TORFSD
IAC193-NEC043-292200-
/O.NEW.KFSD.TO.W.0019.170629T2123Z-170629T2200Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Sioux Falls SD
423 PM CDT THU JUN 29 2017

The National Weather Service in Sioux Falls has issued a

* Tornado Warning for...
  West central Woodbury County in west central Iowa...
  Northeastern Dakota County in northeastern Nebraska...

* Until 500 PM CDT
    
* At 423 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Dakota City, or near Sioux City, moving east at 20
  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...
  South Sioux City and Dakota City around 435 PM CDT. 
  Sergeant Bluff around 445 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 4241 9657 4247 9653 4246 9618 4232 9631
TIME...MOT...LOC 2123Z 283DEG 18KT 4243 9649 

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

$$

Weisser

3 follow-up statements

178 
WWUS53 KFSD 292134
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
434 PM CDT THU JUN 29 2017

IAC193-NEC043-292200-
/O.CON.KFSD.TO.W.0019.000000T0000Z-170629T2200Z/
Woodbury IA-Dakota NE-
434 PM CDT THU JUN 29 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM CDT FOR WEST
CENTRAL WOODBURY AND NORTHEASTERN DAKOTA COUNTIES...
    
At 433 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Dakota City, or near Sioux City, moving east at 20
mph.

HAZARD...Tornado and very large hail. 

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...
  Sergeant Bluff around 445 PM CDT. 

At 430 pm CDT...softball sized hail was reported 1 mile south of 
south Sioux City. Rotation is also being reported with this storm.

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 4241 9657 4247 9653 4246 9618 4232 9631
TIME...MOT...LOC 2133Z 283DEG 18KT 4242 9642 

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

$$

Weisser

223 
WWUS53 KFSD 292143
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
443 PM CDT THU JUN 29 2017

NEC043-292153-
/O.CAN.KFSD.TO.W.0019.000000T0000Z-170629T2200Z/
Dakota NE-
443 PM CDT THU JUN 29 2017

...THE TORNADO WARNING FOR NORTHEASTERN DAKOTA COUNTY IS CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved east 
of the warned area. Therefore, the warning has been cancelled.

A severe thunderstorm watch remains in effect until 1100 PM CDT for
west central Iowa...and northeastern Nebraska.

LAT...LON 4236 9642 4238 9641 4239 9641 4246 9638
      4246 9618 4232 9631
TIME...MOT...LOC 2143Z 278DEG 18KT 4240 9630 

$$

IAC193-292200-
/O.CON.KFSD.TO.W.0019.000000T0000Z-170629T2200Z/
Woodbury IA-
443 PM CDT THU JUN 29 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM CDT FOR WEST
CENTRAL WOODBURY COUNTY...
    
At 443 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Sergeant Bluff, or 8 miles southeast of Sioux City,
moving east at 20 mph.

HAZARD...Tornado and baseball size hail. 

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 tornadic thunderstorm will remain over mainly rural areas of
west central Woodbury County.

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.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 4236 9642 4238 9641 4239 9641 4246 9638
      4246 9618 4232 9631
TIME...MOT...LOC 2143Z 278DEG 18KT 4240 9630 

TORNADO...RADAR INDICATED
HAIL...2.75IN

$$

Weisser

673 
WWUS53 KFSD 292155
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
455 PM CDT THU JUN 29 2017

IAC193-292205-
/O.EXP.KFSD.TO.W.0019.000000T0000Z-170629T2200Z/
Woodbury IA-
455 PM CDT THU JUN 29 2017

...THE TORNADO WARNING FOR WEST CENTRAL WOODBURY COUNTY WILL EXPIRE
AT 500 PM CDT...
        
The storm which prompted the warning has moved out of the area.
Therefore the warning will be allowed to expire.  However gusty winds
to 50 mph are still possible with this thunderstorm.

A severe thunderstorm watch remains in effect until 1100 PM CDT for
west central Iowa...and northeastern Nebraska.

LAT...LON 4236 9642 4238 9641 4239 9641 4246 9638
      4246 9618 4232 9631
TIME...MOT...LOC 2155Z 283DEG 18KT 4239 9622 

$$

Weisser

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 29, 3:22 PM CDT	Severe Thunderstorm Warning	FSD	Dakota, Dixon	53 min
Jun 29, 3:48 PM CDT	Severe Thunderstorm Warning	FSD	Dakota, Dixon	42 min
Jun 29, 4:26 PM CDT	Severe Thunderstorm Warning	FSD	Dakota	49 min
Jun 29, 4:47 PM CDT	Flash Flood Warning	FSD	Dakota	3 hr
Jun 29, 5:39 PM CDT	Severe Thunderstorm Warning	FSD	Dixon	36 min
Jun 29, 6:03 PM CDT	Severe Thunderstorm Warning	FSD	Dixon	27 min
Jun 29, 6:12 PM CDT	Tornado Warning	FSD	Dixon	18 min
Jun 29, 6:27 PM CDT	Severe Thunderstorm Warning	FSD	Dixon	33 min
Jun 29, 4:08 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth	52 min
Jun 29, 4:46 PM CDT	Tornado Warning	FSD	Woodbury	29 min
Jun 29, 4:54 PM CDT	Severe Thunderstorm Warning	FSD	Sioux	51 min
Jun 29, 5:10 PM CDT	Severe Thunderstorm Warning	FSD	Woodbury	35 min
Jun 29, 5:29 PM CDT	Severe Thunderstorm Warning	FSD	Clay	33 min
Jun 29, 5:30 PM CDT	Tornado Warning	FSD	Woodbury	30 min
Jun 29, 5:43 PM CDT	Severe Thunderstorm Warning	FSD	Lyon, Sioux	18 min
Jun 29, 5:59 PM CDT	Severe Thunderstorm Warning	FSD	Ida, Woodbury	22 min

Nearby

Tornado Warnings in Nebraska, 2017 Tornado Warnings in Iowa, 2017 Every tornado warning in 2017 Tornadoes in 2017

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.