Northern Lights Tonight in Ontario
Ontario ranges from the Toronto area, where you need a strong storm, to the Hudson Bay lowlands, where moderate activity is enough. Thresholds run from Kp 3.3 to 5.1. Tonight's peak Kp is 3.7 (active): best chance at Thunder Bay, low.
Best chance in Ontario tonight
LowThunder Bay: low, peak Kp 3.7 against Kp 3.9 needed, clouds 6%.
Kp requirements by location
1Moosonee
| On the horizon | Kp 3.3 |
| Clearly visible | Kp 4.3 |
| Bright, overhead | Kp 5.3 |
Kp now 2.0: 1.3 short of the horizon
2Thunder Bay
| On the horizon | Kp 3.9 |
| Clearly visible | Kp 4.9 |
| Bright, overhead | Kp 5.9 |
Kp now 2.0: 1.9 short of the horizon
3Sudbury
| On the horizon | Kp 4.4 |
| Clearly visible | Kp 5.4 |
| Bright, overhead | Kp 6.4 |
Kp now 2.0: 2.4 short of the horizon
| On the horizon | Kp 4.8 |
| Clearly visible | Kp 5.8 |
| Bright, overhead | Kp 6.8 |
Kp now 2.0: 2.8 short of the horizon
| On the horizon | Kp 5.1 |
| Clearly visible | Kp 6.1 |
| Bright, overhead | Kp 7.1 |
Kp now 2.0: 3.1 short of the horizon
Best dark sky viewing locations
Torrance Barrens Conservation Reserve
Dark-Sky Preserve (RASC)
Open rock barrens in Muskoka, the first dark-sky preserve in Canada (1999). Wide sky and no tall trees near the barrens.
Road access from Gravenhurst; a short walk onto the rock.
Killarney Provincial Park
Dark-Sky Preserve (RASC)
Georgian Bay shoreline park designated in 2018, with white quartzite hills and lakes that open the sky toward the north.
Paved highway spur to the park; interior by trail or canoe.
Lake Superior Provincial Park
Dark-Sky Preserve (RASC)
Long Lake Superior shoreline designated in 2018. The big water lies south, so aim for clearings and beaches with a view of the north.
The Trans-Canada Highway crosses the park.
Bruce Peninsula National Park
Dark-Sky Preserve (RASC)
Georgian Bay and Lake Huron shores with limestone cliffs, designated in 2009. Open sky over the water.
Paved road from Tobermory; park trails to the shore.
Where to see the northern lights in Ontario
The best chances are in the north of the province. Thunder Bay, on Lake Superior, is the main northern city, with forest and Lake Superior shoreline within reach. Moosonee, at the end of the railway on the James Bay lowlands, is the most northerly point and the easiest on the Kp scale, but it is remote, so plan the trip ahead. Sudbury and the Georgian Bay coast sit between the two.
For a dark-sky park, Ontario has several RASC preserves: Torrance Barrens in Muskoka, Killarney and Bruce Peninsula on Georgian Bay, Lake Superior Provincial Park, and the whole of North Frontenac Township. Torrance Barrens is the nearest to Toronto. The rest need a night away, and a clear forecast matters more than the Kp number. Where you can, look from a shore or clearing that faces north.
Aurora status by city
Thunder Bay
Moosonee
Sudbury
Ottawa
Toronto
What time to look tonight in Ontario
Best window tonight: 10 PM – 12 AM EST at Thunder Bay. Look north, low on the horizon; the hours around local midnight are usually the most active.
Best viewing season in Ontario
Ontario is long from south to north, and the aurora follows the same line. Southern Ontario, with its big cities and the Great Lakes, is the hardest part: lake-effect cloud and city light combine, and strong storms are the only reliable chances. From Sudbury north, forest and lakes replace the city glow and the thresholds drop.
The best months run from autumn into early spring, when nights are long and the air is dry. Northern Ontario around Thunder Bay and the James Bay lowlands has the darkest sky, but the clearest nights are the cold ones.
Peak aurora months
At Moosonee, Kp most often reaches the threshold on dark nights in March, April, September and October.
GFZ Potsdam Kp since 2015; clouds not counted.
Ontario northern lights FAQ
Can you see the northern lights in Ontario?
Can I see the northern lights in Ontario tonight?
Where are the darkest skies in Ontario?
What Kp do I need to see the northern lights in Ontario?
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Track aurora across Ontario
The forecast on this page, watching your location all night and telling you when to step outside.
The hour tonight when Kp, clouds and darkness line up for your spot.
A push alert 30–90 minutes before the aurora reaches your sky, even at 2 AM.
Where the clouds open nearby, so you know which way to drive.
Explore more
Learn more about the northern lights
How to See the Northern Lights: A Beginner's Guide
Three conditions decide whether you see the northern lights: activity at your latitude, a clear sky and darkness. Here is how to check each one.
Aurora Colors and What They Mean
Green, red, blue, purple and pink aurora explained: which gas makes each color, how high it glows, and why your camera shows more than your eyes.
Northern Lights in Canada: Best Places
The best places to see the northern lights in Canada: Yellowknife, Whitehorse, Churchill, Jasper and the prairies, plus what Ontario and Quebec get.
Northern Lights in Scotland
Where to see the northern lights in Scotland: north coast, islands, Cairngorms and dark sky parks, when the sky is dark enough, and how to beat cloud.
Northern Lights in Norway
Where to see the northern lights in Norway, which months work, why the coast and inland need different plans, and what Oslo gets in a storm.
Aurora Australis Forecast Guide
How to read a forecast for the southern lights: Kp, Bz, the southern oval, darkness, moon and cloud, plus where to look in Tasmania and southern Australia.
Kp index today
Live Kp, the 3-day and 27-day forecast, and what Kp each city needs.
Geomagnetic storm today
G-scale now, the storm outlook and how far south the aurora reaches.