Alert archive / Minnesota / Tornado Watches in 2017
Tornado Watch 454
The Storm Prediction Center issued this tornado watch at Aug 16, 2017, 7:00 PM CDT for 9 counties in Minnesota. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 16, 2017, 7:00 PM CDT (00:00 UTC)
- Expired
- Aug 16, 2017, 10:00 PM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
Counties Carver County, MN, Kandiyohi County, MN, Le Sueur County, MN, McLeod County, MN, Meeker County, MN, Renville County, MN, Scott County, MN, Sibley County, MN, Wright County, MN
The radar
The Minneapolis radar (KMPX), 65 km from the middle of the area, began a volume at 00:02 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
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 10%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 30%
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 16, 7:42 PM CDT | Tornado Warning | MPX | Carver, Hennepin, Scott | 20 min |
| Aug 16, 7:59 PM CDT | Tornado Warning | MPX | Carver, McLeod | 31 min |
| Aug 16, 8:13 PM CDT | Flash Flood Warning | MPX | Carver, Hennepin, Scott | 3 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Minneapolis, MN (KMPX), launched 00:00Z, 0.0 hours before the alert went out and 62 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
- 445 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 756 m above ground
- 0-6 km bulk shear
- 56 kt
- 0-1 km storm-relative helicity
- 217 m²/s²
- 0-3 km storm-relative helicity
- 238 m²/s²
- Significant tornado parameter
- 0.6
- Supercell composite
- 3.6
The text
As transmitted.
764 WWUS20 KWNS 162358 SEL4 SPC WW 162358 MNZ000-170300- URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 454 NWS Storm Prediction Center Norman OK 700 PM CDT Wed Aug 16 2017 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Southern Minnesota * Effective this Wednesday evening from 700 PM until 1000 PM CDT. * Primary threats include... A couple tornadoes possible SUMMARY...Short-fused tornado threat may continue from a few showers and thunderstorms interacting with a narrow corridor of favorable shear and at least marginal buoyancy over the area. The tornado watch area is approximately along and 30 statute miles north and south of a line from 25 miles north of Redwood Falls MN to 85 miles east of Redwood Falls MN. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...CONTINUE...WW 453... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 16025. ...Edwards
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 16, 9:00 PM CDT | Mesoscale Discussion | SPC | Carver, Hennepin, Kandiyohi, McLeod, Meeker, Renville and 2 more | 90 min |
Nearby
Tornado Watches in Minnesota, 2017Every tornado 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.