Alert archive / South Dakota / Tornado Warnings in 2015

Tornado Warning 23, NWS Sioux Falls, SD

July 25, 2015Lake County, South Dakota

NWS Sioux Falls, SD issued this tornado warning at Jul 25, 2015, 9:43 PM CDT for Lake County, South Dakota. It was in force for 19 min. 2 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: Jul 25, 2015, 9:43 PM CDT (02:43 UTC)
Expired: Jul 25, 2015, 10:02 PM CDT
In force: 19 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Lake County, SD

The radar

The Sioux Falls radar (KFSD), 53 km from the middle of the area, began a volume at 02:43 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
Jul 25, 9:50 PM CDT	TSTM WND GST 65	Madison, SD	EMPTY SEMI TRAILER BLOWN OVER...TREE DAMAGE AND SEVERAL LARGE TREES DOWNED
Jul 25, 9:50 PM CDT	TSTM WND GST 65	Madison, SD	MANUFACTURED HOME KNOCKED OFF TRAILER

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
Jul 25, 4:03 PM CDT	Tornado Watch	SPC	7 hr
Jul 25, 9:32 PM CDT	Severe Thunderstorm Watch	SPC	3 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 2.7 hours before the alert went out and 286 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: 907 J/kg
Mixed-layer CIN: -98 J/kg
Mixed-layer LCL: 1251 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: -17 m²/s²
0-3 km storm-relative helicity: 50 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.5

Open this sounding in Storm Lab

The text

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

879 
WFUS53 KFSD 260243
TORFSD
SDC079-260315-
/O.NEW.KFSD.TO.W.0023.150726T0243Z-150726T0315Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
943 PM CDT SAT JUL 25 2015

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHERN LAKE COUNTY IN EAST CENTRAL SOUTH DAKOTA...

* UNTIL 1015 PM CDT
    
* AT 943 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED NEAR MADISON...MOVING SOUTHEAST AT 35 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...
  WENTWORTH AROUND 1000 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 4406 9692 4405 9689 4400 9689 4386 9695
      4401 9728 4410 9719
TIME...MOT...LOC 0243Z 293DEG 30KT 4404 9716 

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

$$

JM

1 follow-up statement

252 
WWUS53 KFSD 260302
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1002 PM CDT SAT JUL 25 2015

SDC079-260311-
/O.CAN.KFSD.TO.W.0023.000000T0000Z-150726T0315Z/
LAKE SD-
1002 PM CDT SAT JUL 25 2015

...THE TORNADO WARNING FOR SOUTHERN LAKE 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.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 100 AM CDT FOR
EAST CENTRAL SOUTH DAKOTA.

LAT...LON 4406 9692 4405 9689 4400 9689 4386 9695
      4401 9728 4410 9719
TIME...MOT...LOC 0300Z 293DEG 30KT 4398 9696 

$$

JM

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 25, 8:14 PM CDT	Severe Thunderstorm Warning	FSD	Beadle, Jerauld, Kingsbury, Sanborn	46 min
Jul 25, 8:25 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Beadle, Brule, Jerauld	50 min
Jul 25, 8:47 PM CDT	Severe Thunderstorm Warning	FSD	Beadle, Brookings, Kingsbury	43 min
Jul 25, 9:13 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule, Jerauld	47 min
Jul 25, 9:17 PM CDT	Severe Thunderstorm Warning	FSD	Kingsbury, Lake, Miner	43 min
Jul 25, 9:24 PM CDT	Severe Thunderstorm Warning	FSD	Brookings, Kingsbury, Lake, Miner	36 min
Jul 25, 10:13 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule, Charles Mix, Davison, Douglas	32 min
Jul 25, 10:43 PM CDT	Severe Thunderstorm Warning	FSD	Douglas, Hutchinson	47 min
Jul 25, 11:05 PM CDT	Severe Thunderstorm Warning	FSD	Bon Homme, Charles Mix, Hutchinson	40 min
Jul 25, 11:47 PM CDT	Severe Thunderstorm Warning	FSD	Bon Homme	17 min

Nearby

Tornado Warnings in South Dakota, 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.