Alert archive / South Dakota / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 580
The Storm Prediction Center issued this severe thunderstorm watch at Jun 30, 2011, 10:07 PM CDT for 22 counties in South Dakota. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 30, 2011, 10:07 PM CDT (03:07 UTC)
- Expired
- Jul 1, 2011, 1:06 AM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 22 counties
Aurora County, SD, Beadle County, SD, Brule County, SD, Buffalo County, SD, Clark County, SD, Codington County, SD, Davison County, SD, Deuel County, SD, Faulk County, SD, Grant County, SD, Hamlin County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jerauld County, SD, Jones County, SD, Kingsbury County, SD, Lyman County, SD, Sanborn County, SD, Spink County, SD, Stanley County, SD, Sully County, SD
The radar
The Aberdeen radar (KABR), 142 km from the middle of the area, began a volume at 03:08 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
- 5%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 30, 10:07 PM CDT | Severe Thunderstorm Warning | FSD | Brule, Charles Mix, Gregory | 38 min |
| Jun 30, 10:12 PM CDT | Severe Thunderstorm Warning | ABR | Buffalo, Lyman | 48 min |
| Jun 30, 10:46 PM CDT | Severe Thunderstorm Warning | ABR | Buffalo, Dewey, Hand, Hughes, Hyde, Lyman and 2 more | 44 min |
| Jun 30, 10:47 PM CDT | Severe Thunderstorm Warning | FSD | Brule | 43 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 00:00Z, 3.1 hours before the alert went out and 88 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
- 1704 J/kg
- Mixed-layer CIN
- -238 J/kg
- Mixed-layer LCL
- 2151 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 74 m²/s²
- 0-3 km storm-relative helicity
- 182 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.7
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 30, 8:25 PM CDT | Mesoscale Discussion | SPC | Bennett, Fall River, Jackson, Oglala Lakota | 2 hr |
| Jun 30, 9:58 PM CDT | Mesoscale Discussion | SPC | Beadle, Brule, Buffalo, Hughes, Jerauld, Jones and 4 more | 32 min |
| Jul 1, 12:59 PM CDT | Mesoscale Discussion | SPC | Aurora, Beadle, Bon Homme, Brookings, Charles Mix, Clark and 24 more | 61 min |
| Jul 1, 2:08 PM CDT | Severe Thunderstorm Watch | SPC | Brookings, Codington, Deuel, Grant, Hamlin, Kingsbury and 8 more | 9 hr |
Nearby
Severe Thunderstorm Watches in South Dakota, 2011Every severe thunderstorm watch in 2011
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.