THUNDER BAY – WEATHER – Sunshine is forecast through Monday, with Sunday reaching 18°C. Cool nights will contrast with the warmer afternoons. This report uses Environment Canada’s forecast issued at 4:00 p.m. EDT Friday, October 16, 2026.
Early morning conditions
At 1:00 a.m. Saturday, Thunder Bay Airport reported partly cloudy skies and −0.3°C, with a wind chill of −2. Winds were northwest at 5 km/h, humidity was 88 per cent, and pressure was 102.8 kPa and falling.
Your three-day forecast
| Day | Forecast | High | Overnight |
|---|---|---|---|
| Saturday, October 17 | Sunny; west wind becoming 20 km/h in the morning | 14°C | Clear, low 3°C |
| Sunday, October 18 | Sunny | 18°C | Clear, low 3°C |
| Monday, October 19 | Sunny | 16°C | Clear, low 0°C |
Saturday’s UV index is 3, or moderate. Southwest winds of 20 km/h become light Saturday evening. Detailed wind forecasts for Sunday and Monday were not included in this bulletin.
What to wear
Dress in layers for the change between chilly mornings and warmer afternoons. A sweater and wind-resistant jacket will be useful early, with lighter clothing underneath for afternoon walks or yardwork. Keep sunglasses handy.
Weather trivia
Environment Canada lists a normal high of 10°C and low of −1°C for this forecast period—putting Sunday’s predicted high eight degrees above normal.
