Will you see the northern lights tonight?

Space weather

The Kp index, yesterday to three days out.

Each bar is three hours. Green bars are active enough for the aurora on Lake Superior's north shore; red bars are geomagnetic storms that can bring it farther south. Faded bars have already happened.

Tonight

Where to look tonight, best chance first.

Ratings combine the forecast Kp each spot needs, the hourly cloud forecast and moonlight, for the best hour of darkness tonight.

1. Sleeping Giant Provincial Park ON

   Needs about Kp 3.8 here; tonight's forecast peaks near Kp 1.7.

   The northernmost spot here, so the aurora shows up at the lowest Kp; Thunder Cape looks over open water.

   • Needs about Kp 3.8
   • Dark 7 pm–6 am ET
   • Best hour 7 pm ET
   • Sky Clear
   Unlikely

2. Grand Marais MN

   Needs about Kp 4.1 here; tonight's forecast peaks near Kp 1.7.

   Artist's Point and the harbor breakwall face straight out over Lake Superior, far from city glow.

   • Needs about Kp 4.1
   • Dark 6 pm–5 am CT
   • Best hour 6 pm CT
   • Sky Mostly Clear
   Unlikely

3. Bayfield & the Apostle Islands WI

   Needs about Kp 4.5 here; tonight's forecast peaks near Kp 1.7.

   Little Sand Bay and Meyers Beach have dark, north-facing shoreline toward the islands.

   • Needs about Kp 4.5
   • Dark 6 pm–5 am CT
   • Best hour 6 pm CT
   • Sky Mostly Clear
   Unlikely

4. Whitefish Point MI

   Needs about Kp 4.5 here; tonight's forecast peaks near Kp 1.7.

   A remote point jutting into Lake Superior with nothing but water and dark sky to the north.

   • Needs about Kp 4.5
   • Dark 6 pm–5 am ET
   • Best hour 6 pm ET
   • Sky Cloudy
   Unlikely

5. Marquette MI

   Needs about Kp 4.6 here; tonight's forecast peaks near Kp 1.7.

   Presque Isle Park and Sugarloaf Mountain give open views north over Lake Superior.

   • Needs about Kp 4.6
   • Dark 7 pm–6 am ET
   • Best hour 7 pm ET
   • Sky Mostly Cloudy
   Unlikely

6. Headlands Dark Sky Park MI

   Needs about Kp 4.9 here; tonight's forecast peaks near Kp 1.7.

   An official International Dark Sky Park on the Straits of Mackinac, open all night year-round.

   • Needs about Kp 4.9
   • Dark 6 pm–5 am ET
   • Best hour 6 pm ET
   • Sky Cloudy
   Unlikely

7. Bruce Peninsula ON

   Needs about Kp 5.1 here; tonight's forecast peaks near Kp 1.7.

   A Dark Sky Preserve; Cyprus Lake's shoreline looks north over Georgian Bay.

   • Needs about Kp 5.1
   • Dark 6 pm–5 am ET
   • Best hour 6 pm ET
   • Sky No forecast
   Unlikely

8. Port Crescent & Port Austin MI

   Needs about Kp 5.6 here; tonight's forecast peaks near Kp 1.7.

   Port Crescent State Park is a designated dark sky preserve facing north over Saginaw Bay and Lake Huron.

   • Needs about Kp 5.6
   • Dark 6 pm–5 am ET
   • Best hour 6 pm ET
   • Sky Cloudy
   Unlikely

9. Point Pelee ON

   Needs about Kp 6.4 here; tonight's forecast peaks near Kp 1.7.

   The southern tip of Canada needs a strong storm, but its dark sky preserve looks north over Lake Erie.

   • Needs about Kp 6.4
   • Dark 6 pm–5 am ET
   • Best hour 6 pm ET
   • Sky No forecast
   Unlikely

Coming nights

The next three nights on Lake Superior.

The strongest forecast Kp during darkness and the moon, assuming clear skies on Lake Superior's south shore. Cloud forecasts this far out are too uncertain to include.

Field notes

How to see the northern lights on the Great Lakes.

• Find a beach, breakwall or overlook facing north over the water, well away from town lights.
• Give your eyes 20 minutes to adjust to the dark, and use a red light instead of your phone screen.
• Point your phone camera north in night mode. It often picks up a faint green or pink glow your eyes miss.
• Watch from about 10 pm to 2 am, and keep checking: displays can flare up and fade within minutes.
• Dress for the shore. Even in summer, nights on Lake Superior are cold and windy.

Northern lights questions.

Can you see the northern lights from the Great Lakes?

Yes. Lake Superior's north shore, Michigan's Upper Peninsula and the Bruce Peninsula see the aurora several times a year, and strong geomagnetic storms push it over Lake Michigan, Lake Huron and even Lake Erie. The lakes help: a dark, north-facing shoreline gives you an unobstructed horizon with no city lights.

What Kp index do I need to see the aurora?

It depends on how far north you are. As a rule of thumb, Thunder Bay and Sleeping Giant need about Kp 3.8, Grand Marais and Marquette about Kp 4.4, the Straits of Mackinac about Kp 4.9 and Lake Erie's shore about Kp 6.4 for the lights to show low on the northern horizon. Higher numbers bring them overhead.

When is the best time to see the northern lights?

Activity usually peaks between about 10 pm and 2 am local time. The months around the equinoxes, March–April and September–October, are statistically the most active, but displays happen all year. Summer nights are short this far north, so clear, dark winter and fall nights give you the most hours to watch.

How does this forecast work?

For each viewing spot we combine NOAA's three-day Kp forecast and its 30-minute OVATION aurora nowcast with the hourly sky-cover forecast from the National Weather Service or Environment Canada and the phase of the moon, then pick the best hour of darkness. Aurora forecasts are uncertain more than a few hours out, so check again in the evening.

Space weather: NOAA Space Weather Prediction Center planetary Kp forecast and OVATION aurora nowcast (Sat 6 pm ET). Sky cover: National Weather Service and Environment and Climate Change Canada hourly forecasts. Moon and darkness are calculated for each spot. Aurora forecasts are uncertain; ratings are a guide, not a guarantee.

More planning tools: water temperatures, ship watcher, circle tour planner and the trip builder.