Alert archive / South Dakota / Tornado Warnings in 2017

Tornado Warning 26, NWS Sioux Falls, SD

July 25, 2017Brookings County, Moody County, South Dakota

NWS Sioux Falls, SD issued this tornado warning at Jul 25, 2017, 4:39 PM CDT for Brookings County, Moody County, South Dakota. It was in force for 36 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 25, 2017, 4:39 PM CDT (21:39 UTC)
Expired: Jul 25, 2017, 5:15 PM CDT
In force: 36 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.0 in

Counties Brookings County, SD, Moody County, SD

The radar

The Sioux Falls radar (KFSD), 79 km from the middle of the area, began a volume at 21:39 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 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

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 9.7 hours before the alert went out and 145 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.

487 
WFUS53 KFSD 252139
TORFSD
SDC011-101-252215-
/O.NEW.KFSD.TO.W.0026.170725T2139Z-170725T2215Z/

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

The National Weather Service in Sioux Falls has issued a

* Tornado Warning for...
  Northwestern Moody County in east central South Dakota...
  Southern Brookings County in east central South Dakota...

* Until 515 PM CDT
    
* At 438 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Volga, or 8 miles west of Brookings, moving
  southeast at 20 mph.

  HAZARD...Tornado, 70 mph winds, 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...
  Brookings around 505 PM CDT. 
  Aurora around 515 PM CDT. 

Other locations impacted by this tornadic thunderstorm include
Bushnell.

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 4433 9657 4410 9677 4431 9705 4442 9694
TIME...MOT...LOC 2138Z 294DEG 17KT 4433 9696 

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

$$

Hanko

2 follow-up statements

678 
WWUS53 KFSD 252154
SVSFSD

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

SDC011-101-252215-
/O.CON.KFSD.TO.W.0026.000000T0000Z-170725T2215Z/
Moody SD-Brookings SD-
454 PM CDT TUE JUL 25 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 515 PM CDT FOR NORTH
CENTRAL MOODY AND SOUTHEASTERN BROOKINGS COUNTIES...
    
At 453 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Brookings, moving east at 25 mph.

HAZARD...Tornado, 60 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 dangerous storm will be near...
  Aurora around 510 PM CDT. 

Other locations impacted by this tornadic thunderstorm include
Bushnell.

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 4433 9657 4416 9673 4434 9692 4440 9687
TIME...MOT...LOC 2153Z 280DEG 21KT 4434 9682 

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

$$

Hanko

174 
WWUS53 KFSD 252207
SVSFSD

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

SDC011-101-252216-
/O.EXP.KFSD.TO.W.0026.000000T0000Z-170725T2215Z/
Moody SD-Brookings SD-
507 PM CDT TUE JUL 25 2017

...THE TORNADO WARNING FOR NORTH CENTRAL MOODY AND SOUTHEASTERN
BROOKINGS COUNTIES WILL EXPIRE AT 515 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.

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

LAT...LON 4433 9657 4416 9673 4434 9692 4440 9687
TIME...MOT...LOC 2206Z 294DEG 17KT 4431 9674 

$$

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, 4:12 PM CDT	Tornado Warning	FSD	Brookings	33 min
Jul 25, 4:34 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Davison, Hanson, Jerauld, Miner, Sanborn	41 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 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.