Alert archive / Michigan / Severe Thunderstorm Watches in 2017
Severe Thunderstorm Watch 321
The Storm Prediction Center issued this severe thunderstorm watch at Jun 12, 2017, 9:09 PM EDT for 40 counties in Michigan. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 12, 2017, 9:09 PM EDT (01:09 UTC)
- Expired
- Jun 13, 2017, 2:09 AM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
All 40 counties
Alcona County, MI, Antrim County, MI, Arenac County, MI, Bay County, MI, Benzie County, MI, Charlevoix County, MI, Clare County, MI, Clinton County, MI, Crawford County, MI, Emmet County, MI, Gladwin County, MI, Grand Traverse County, MI, Gratiot County, MI, Huron County, MI, Ionia County, MI, Iosco County, MI, Isabella County, MI, Kalkaska County, MI, Kent County, MI, Lake County, MI, Leelanau County, MI, Manistee County, MI, Mason County, MI, Mecosta County, MI, Midland County, MI, Missaukee County, MI, Montcalm County, MI, Muskegon County, MI, Newaygo County, MI, Oceana County, MI, Ogemaw County, MI, Osceola County, MI, Oscoda County, MI, Otsego County, MI, Ottawa County, MI, Roscommon County, MI, Saginaw County, MI, Shiawassee County, MI, Tuscola County, MI, Wexford County, MI
The radar
The NCL Michigan radar (KAPX), 109 km from the middle of the area, began a volume at 01:13 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 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
- 30%
- 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
- 40%
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 12, 10:34 PM EDT | Severe Thunderstorm Warning | APX | Benzie, Grand Traverse, Leelanau, Manistee, Wexford | 56 min |
| Jun 12, 11:20 PM EDT | Severe Thunderstorm Warning | APX | Antrim, Charlevoix, Grand Traverse, Leelanau | 35 min |
| Jun 12, 11:30 PM EDT | Severe Thunderstorm Warning | APX | Antrim, Crawford, Grand Traverse, Kalkaska, Missaukee, Wexford | 60 min |
| Jun 13, 12:36 AM EDT | Severe Thunderstorm Warning | APX | Alcona, Crawford, Iosco, Ogemaw, Oscoda, Roscommon | 54 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
Detroit, MI (KDTX), launched 00:00Z, 1.2 hours before the alert went out and 210 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
- 827 J/kg
- Mixed-layer CIN
- -151 J/kg
- Mixed-layer LCL
- 1731 m above ground
- 0-6 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 58 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
487 WWUS20 KWNS 130105 SEL1 SPC WW 130105 MIZ000-LHZ000-LMZ000-130800- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 321 NWS Storm Prediction Center Norman OK 905 PM EDT Mon Jun 12 2017 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Central Lower Michigan Lake Huron Lake Michigan * Effective this Monday night and Tuesday morning from 905 PM until 400 AM EDT. * Primary threats include... Isolated damaging wind gusts to 70 mph possible SUMMARY...A well-developed, occasionally severe, bowing arc of thunderstorms in eastern Wisconsin may survive its trek across a shallow/stable marine layer of Lake Michigan and pose a threat of damaging wind in Lower Michigan. The severe thunderstorm watch area is approximately along and 70 statute miles north and south of a line from 45 miles southwest of Manistee MI to 5 miles north northeast of Bad Axe MI. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 317...WW 318...WW 319...WW 320... AVIATION...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 27035. ...Edwards
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 12, 10:30 PM EDT | Mesoscale Discussion | SPC | Alcona, Arenac, Bay, Benzie, Clare, Clinton and 29 more | 90 min |
| Jun 13, 12:58 AM EDT | Mesoscale Discussion | SPC | Alcona, Alpena, Crawford, Gladwin, Iosco, Montmorency and 3 more | 92 min |
Nearby
Severe Thunderstorm Watches in Michigan, 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.