Northern Lights tonight in Trois-Rivières, QC

Tonight in Trois-Rivières

Trois-Rivières sits at a geomagnetic latitude of 55.5° N, so the aurora usually needs a Kp index of about 4 or higher before it rises above the northern horizon. Tonight's NOAA forecast peaks at Kp 3 (quiet) during the dark hours, 1.0 short of what Trois-Rivières needs.

The Moon is 100% illuminated (full moon), bright enough to wash out a faint aurora, so only a stronger display will stand out. For the best view look north, low on the horizon, from somewhere away from street lights.

Right now NOAA's OVATION model gives up to 1% chance of aurora in the part of the sky visible from Trois-Rivières. OVATION is a short-range nowcast (30 to 90 minutes ahead), useful for deciding whether to step outside now.

3-day Kp forecast

None of the next 3 days reaches the Kp 4 that Trois-Rivières needs. Kp is a global 0–9 index of geomagnetic activity, issued in 3-hour blocks (UTC); NOAA forecasts beyond 24 hours are uncertain, because storms are triggered by solar eruptions that take 1–3 days to arrive.

Why Trois-Rivières needs Kp 4

The aurora forms in an oval around the geomagnetic pole, which sits in the Canadian Arctic (about 80.8° N, 72.8° W), not at the geographic pole. That is why North American cities see aurora further south than European cities at the same latitude. At Kp 0 the oval's edge is near 66° geomagnetic; each step of Kp pushes it roughly 2° toward the equator.

At 55.5° geomagnetic, Trois-Rivières needs about Kp 4 for aurora low on the horizon, Kp 6 or more for a display high in the sky.

Aurora forecast for nearby cities

• Northern lights Shawinigan
• Northern lights Drummondville
• Northern lights Sorel-Tracy
• Northern lights Victoriaville
• Northern lights Joliette
• Northern lights Saint-Hyacinthe
• Northern lights Repentigny
• Northern lights Mascouche

More sky and weather

• Aurora forecast (all cities)
• Northern Taurids meteor shower
• Meteor showers
• Wildfires near Trois-Rivières
• Weather warnings