Alert archive / South Dakota / Tornado Warnings in 2017

Tornado Warning 25, NWS Sioux Falls, SD

July 25, 2017Brookings County, South Dakota; Lincoln County, Minnesota

NWS Sioux Falls, SD issued this tornado warning at Jul 25, 2017, 4:12 PM CDT for Brookings County, South Dakota; Lincoln County, Minnesota. It was in force for 33 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, 2017, 4:12 PM CDT (21:12 UTC)
Expired: Jul 25, 2017, 4:45 PM CDT
In force: 33 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.0 in

Counties Lincoln County, MN, Brookings County, SD

The radar

The Sioux Falls radar (KFSD), 101 km from the middle of the area, began a volume at 21:13 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, 4:28 PM CDT	HAIL 1.5	5 Nnw White, SD	WELCOMED HEAVY RAIN, BUT NOT LIKING THE HAIL. WINDS FAIRLY CALM.
Jul 25, 4:45 PM CDT	TSTM WND GST 60	7 E White, SD	KNOCKED SOME SMALL TREES DOWN.

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, 3:22 PM CDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 25, 3:46 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 9.2 hours before the alert went out and 157 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: 853 J/kg
Mixed-layer CIN: -568 J/kg
Mixed-layer LCL: 1011 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 234 m²/s²
0-3 km storm-relative helicity: 238 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

801 
WFUS53 KFSD 252112
TORFSD
MNC081-SDC011-252145-
/O.NEW.KFSD.TO.W.0025.170725T2112Z-170725T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Sioux Falls SD
412 PM CDT TUE JUL 25 2017

The National Weather Service in Sioux Falls has issued a

* Tornado Warning for...
  Northwestern Lincoln County in southwestern Minnesota...
  Northeastern Brookings County in east central South Dakota...

* Until 445 PM CDT
    
* At 411 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near White, or 11 miles southeast of Estelline, moving
  east at 35 mph.

  HAZARD...Tornado and quarter 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 dangerous storm will be near...
  White around 420 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 4454 9631 4429 9640 4439 9683 4454 9678
      4454 9645 4455 9645
TIME...MOT...LOC 2111Z 288DEG 32KT 4446 9674 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Hanko

2 follow-up statements

625 
WWUS53 KFSD 252126
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
426 PM CDT TUE JUL 25 2017

MNC081-SDC011-252145-
/O.CON.KFSD.TO.W.0025.000000T0000Z-170725T2145Z/
Lincoln MN-Brookings SD-
426 PM CDT TUE JUL 25 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 445 PM CDT FOR WEST
CENTRAL LINCOLN AND NORTHEASTERN BROOKINGS COUNTIES...
    
At 425 PM CDT, a severe thunderstorm capable of producing a tornado
was located over White, or 9 miles northeast of Brookings, moving
southeast at 30 mph.

HAZARD...Tornado, 70 mph winds, and ping pong ball 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 Lincoln and northeastern Brookings Counties.

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 4444 9635 4429 9640 4438 9678 4447 9672
TIME...MOT...LOC 2125Z 294DEG 26KT 4441 9664 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

Hanko

731 
WWUS53 KFSD 252136
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
436 PM CDT TUE JUL 25 2017

MNC081-SDC011-252146-
/O.EXP.KFSD.TO.W.0025.000000T0000Z-170725T2145Z/
Lincoln MN-Brookings SD-
436 PM CDT TUE JUL 25 2017

...THE TORNADO WARNING FOR WEST CENTRAL LINCOLN AND NORTHEASTERN
BROOKINGS COUNTIES WILL EXPIRE AT 445 PM CDT...
    
The tornado threat has diminished and the Tornado Warning has been
cancelled. However, large hail and damaging winds remain likely and a
Severe Thunderstorm Warning remains in effect for the area.  However
small hail and gusty winds are still possible with this thunderstorm.

A severe thunderstorm watch remains in effect until 1100 PM CDT for
east central South Dakota. A severe thunderstorm watch also remains
in effect until 1100 PM CDT for southwestern Minnesota.

LAT...LON 4444 9635 4429 9640 4438 9678 4447 9672
TIME...MOT...LOC 2136Z 288DEG 32KT 4438 9651 

$$

Hanko

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 25, 4:09 PM CDT	Severe Thunderstorm Warning	FSD	Brookings	51 min
Jul 25, 4:34 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Davison, Hanson, Jerauld, Miner, Sanborn	41 min
Jul 25, 4:39 PM CDT	Tornado Warning	FSD	Brookings, Moody	36 min
Jul 25, 4:52 PM CDT	Severe Thunderstorm Warning	FSD	Brookings, Moody	38 min
Jul 25, 4:58 PM CDT	Severe Thunderstorm Warning	FSD	Davison, Hanson, Lake, Miner, Sanborn	47 min
Jul 25, 5:21 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule, Davison, Jerauld, Sanborn	39 min
Jul 25, 5:31 PM CDT	Severe Thunderstorm Warning	FSD	Kingsbury, Lake, Miner, Sanborn	44 min

Nearby

Tornado Warnings in South Dakota, 2017 Tornado Warnings in Minnesota, 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.