Alert archive / South Dakota / Severe Thunderstorm Watches in 2017
Severe Thunderstorm Watch 436
The Storm Prediction Center issued this severe thunderstorm watch at Jul 25, 2017, 3:22 PM CDT for 7 counties in Nebraska; 37 counties in South Dakota. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 25, 2017, 3:22 PM CDT (20:22 UTC)
- Expired
- Jul 25, 2017, 11:00 PM CDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2.5 in
- Strongest gust expected
- 70 kt
All 44 counties
Brown County, NE, Cherry County, NE, Grant County, NE, Hooker County, NE, Keya Paha County, NE, Sheridan County, NE, Thomas County, NE, Aurora County, SD, Beadle County, SD, Bennett County, SD, Bon Homme County, SD, Brookings County, SD, Brule County, SD, Buffalo County, SD, Charles Mix County, SD, Clark County, SD, Codington County, SD, Davison County, SD, Day County, SD, Deuel County, SD, Douglas County, SD, Grant County, SD, Gregory County, SD, Hamlin County, SD, Hand County, SD, Hanson County, SD, Hutchinson County, SD, Jerauld County, SD, Kingsbury County, SD, Lake County, SD, Lincoln County, SD, Lyman County, SD, McCook County, SD, Mellette County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Roberts County, SD, Sanborn County, SD, Spink County, SD, Todd County, SD, Tripp County, SD, Turner County, SD, Yankton County, SD
The radar
The North Platte radar (KLNX), 175 km from the middle of the area, began a volume at 20:25 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 10%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 60%
- One or more hailstones of 2 inches or more
- 40%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
18 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| 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, 4:16 PM CDT | Severe Thunderstorm Warning | ABR | Deuel | 29 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 |
| Jul 25, 6:19 PM CDT | Severe Thunderstorm Warning | UNR | Mellette, Todd, Tripp | 56 min |
| Jul 25, 6:23 PM CDT | Severe Thunderstorm Warning | UNR | Tripp | 55 min |
| Jul 25, 7:03 PM CDT | Severe Thunderstorm Warning | UNR | Mellette, Tripp | 57 min |
| Jul 25, 7:13 PM CDT | Severe Thunderstorm Warning | ABR | Lyman | 32 min |
| Jul 25, 7:59 PM CDT | Severe Thunderstorm Warning | ABR | Buffalo, Hughes, Lyman | 31 min |
| Jul 25, 8:00 PM CDT | Severe Thunderstorm Warning | LBF | Cherry, Grant, Hooker | 45 min |
| Jul 25, 8:21 PM CDT | Severe Thunderstorm Warning | FSD | Aurora, Davison, Hanson, Jerauld, Sanborn | 39 min |
| Jul 25, 8:47 PM CDT | Severe Thunderstorm Warning | LBF | Brown, Rock | 43 min |
| Jul 25, 8:51 PM CDT | Severe Thunderstorm Warning | FSD | Davison, Hanson, Miner, Sanborn | 39 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Aberdeen, SD (KABR), launched 12:00Z, 8.4 hours before the alert went out and 201 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.
- 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
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 25, 3:21 PM CDT | Mesoscale Discussion | SPC | Anoka, Benton, Brown, Carver, Chippewa, Dakota and 23 more | 2 hr |
| Jul 25, 3:46 PM CDT | Severe Thunderstorm Watch | SPC | Anoka, Benton, Blue Earth, Brown, Carver, Chippewa and 36 more | 7 hr |
| Jul 25, 6:25 PM CDT | Mesoscale Discussion | SPC | Anoka, Benton, Big Stone, Brown, Carver, Chippewa and 26 more | 95 min |
| Jul 25, 2:41 PM CDT | Mesoscale Discussion | SPC | Boyd, Cherry, Keya Paha, Sheridan | 2 hr |
Nearby
Severe Thunderstorm Watches in South Dakota, 2017Severe Thunderstorm Watches in Nebraska, 2017Every severe thunderstorm watch 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.