Michigan · 7 towns compared
Northern lights in Michigan: tonight’s chance
Michigan spans more magnetic latitude than most states: the Keweenaw sees aurora several storm levels before Detroit does.
Tonight at Traverse City, MI
…
Reading the SWPC Kp forecast and the cloud forecast…
| Kp forecast during the dark hours | not yet forecast |
|---|---|
| Kp needed here | 6.0 (G2 moderate) |
| Cloud cover in the dark hours | loading |
| Dark sky (Sun 18° down) | 8:38 PM to 6:19 AM EDT |
| Moon | 13% lit |
| Right now, OVATION (30 to 90 min) | loading or unavailable |
| Magnetic latitude (AACGM) | 54.0° |
Hour by hour, EDT
8 PM
Kp –
– ☁
No
9 PM
Kp –
– ☁
No
10 PM
Kp –
– ☁
No
11 PM
Kp –
– ☁
No
12 AM
Kp –
– ☁
No
1 AM
Kp –
– ☁
No
2 AM
Kp –
– ☁
No
3 AM
Kp –
– ☁
No
4 AM
Kp –
– ☁
No
5 AM
Kp –
– ☁
No
6 AM
Kp –
– ☁
No
Rules checked · Built by Radif Partners · How the answer works
- Kp to see it from Traverse City
- 6.0
- Storm level needed
- G2 (Moderate)
- Kp for aurora overhead
- 6.0
- Most clear dark hours
- September
Michigan is two aurora states in one. The Upper Peninsula sits close to the line that NOAA's storm scale draws at G1: Houghton, on the Keweenaw Peninsula, is at 56.3 degrees magnetic latitude and needs about Kp 4.9, so a minor storm on a clear night is often enough. The Lower Peninsula slopes away quickly: Traverse City needs about Kp 6.0, a G2 (Moderate) storm, and Detroit about Kp 6.7, which only strong storms deliver. The tool opens on Traverse City; type your own town or ZIP code. In Traverse City the months with the most clear dark hours on average are September and October, from NASA POWER cloud data and the dark hours computed for each month, which is when a modest storm has the best chance of meeting a usable sky.
The Upper Peninsula and the Lake Superior horizon
What sets the U.P. apart is less its latitude than its northern horizon. From Copper Harbor to Whitefish Point the shore faces the open water of Lake Superior, with no town of any size for a hundred miles to the north. An aurora that stands only ten degrees above the horizon, which is what a storm at the edge of your range produces, is visible there when it would be hidden by trees or glow anywhere else. Houghton at 56.3 degrees and Marquette at 55.7 degrees magnetic latitude sit within half a Kp of the G1 threshold, which NOAA's scale describes as the level where aurora is commonly visible in northern Michigan. The Marquette page goes into the details for the central U.P.
The Lower Peninsula, storm by storm
South of the Straits, each level of the NOAA scale opens a new band of the state. Sault Ste. Marie and the Straits are close to the U.P. figures. Traverse City and the Leelanau Peninsula need a G2 (Moderate) storm. Grand Rapids and Lansing need Kp 6.5 to 6.6, and the Detroit area a strong G3 storm. The Grand Rapids page and the Detroit page give the dark hours and cloud figures for those cities.
The Headlands International Dark Sky Park, west of Mackinaw City on the Lake Michigan shore, is one of the darkest public sites in the Lower Peninsula, with a northern view across the water toward the Straits. Along Lake Huron, the shoreline north of Port Huron and the tip of the Thumb offer dark skies within reach of the Detroit area.
Lake effect and the cloud calendar
Michigan's cloud calendar is shaped by the Great Lakes. When cold air crosses the warm open water in late autumn and early winter, it picks up moisture and builds the lake-effect clouds that cover the downwind shores, the western Lower Peninsula and much of the U.P., for days. NASA POWER's averages for Traverse City show it: the cloud amount is highest in December, at 82%, against 53% in July. On a storm night, moving inland, away from the downwind shore, can make the difference.
How dark, how clear: one town, one month
Hours of full darkness on the 15th
8.1 h
| Dark sky | 9:33 PM to 5:42 AM |
| Including nautical twilight | 9.3 h |
| Mean cloud amount (NASA POWER) | 54% |
| Clear dark hours on an average night | 3.7 h |
Computed for 2027; the hours move by a few minutes from one year to the next.
Kp needed across Michigan
| Town | Magnetic latitude | Kp to see it | Kp overhead | Storm level |
|---|---|---|---|---|
| Houghton | 56.3° | 4.9 | 4.9 | G1 (Minor) |
| Marquette | 55.7° | 5.1 | 5.1 | G1 (Minor) |
| Sault Ste. Marie | 55.6° | 5.2 | 5.2 | G1 (Minor) |
| Traverse City | 54.0° | 6.0 | 6.0 | G2 (Moderate) |
| Grand Rapids | 52.3° | 6.5 | 6.9 | G2 (Moderate) |
| Lansing | 52.0° | 6.6 | 7.0 | G2 (Moderate) |
| Detroit | 51.6° | 6.7 | 7.2 | G3 (Strong) |
Darkness and clouds by month in Traverse City
| Month | Dark hours | Dark sky, 15th | Mean cloud | Clear dark hours |
|---|---|---|---|---|
| January | 11.3 h | 7:11 PM to 6:32 AM | 79% | 2.3 h |
| February | 10.2 h | 7:48 PM to 6:03 AM | 76% | 2.5 h |
| March | 8.8 h | 9:26 PM to 6:15 AM | 67% | 2.9 h |
| April | 6.9 h | 10:14 PM to 5:09 AM | 67% | 2.3 h |
| May | 4.9 h | 11:12 PM to 4:04 AM | 66% | 1.7 h |
| June | 3.4 h | 12:00 AM to 3:25 AM | 60% | 1.4 h |
| July | 4.2 h | 11:43 PM to 3:53 AM | 53% | 2.0 h |
| August | 6.2 h | 10:42 PM to 4:52 AM | 54% | 2.8 h |
| September | 8.1 h | 9:33 PM to 5:42 AM | 54% | 3.7 h |
| October | 9.8 h | 8:35 PM to 6:21 AM | 69% | 3.0 h |
| November | 11.1 h | 6:55 PM to 5:58 AM | 76% | 2.7 h |
| December | 11.6 h | 6:48 PM to 6:27 AM | 82% | 2.1 h |