October 5–7, 2025: Thunder Bay Weather Outlook

Thunder Bay is under a Special Weather Statement this Sunday morning as a strong cold front pushes across northwestern Ontario. With temperatures soaring to 25°C and a humidex of 28, it may feel like summer early in the day — but high-impact weather is on the way. Expect damaging wind gusts, the potential for isolated thunderstorms, and a sharp temperature drop overnight as fall returns in full force by Monday.

⚠️ Special Weather Statement Summary – Issued by Environment Canada

• Location: City of Thunder Bay

• Timing: This afternoon through this evening

• Hazards:

  • Wind gusts of 70–90 km/h, especially in open areas

  • Thunderstorms may develop late this afternoon, capable of producing even stronger localized gusts

• Impacts:

  • Loose objects may be tossed or damaged

  • Power outages are possible

  • Travel may be hazardous, especially for high-profile vehicles

  • Boaters should avoid open waters

Current Conditions (as of 5:24 AM EDT)

• Temperature: ~14°C

• Sky: Mix of sun and cloud

• Wind: Calm, shifting and strengthening rapidly through the morning

• Humidity: High

• Pressure: Falling as low-pressure system approaches

Sunday, October 5 Forecast

• Morning:

  • Mix of sun and cloud, 30% chance of isolated showers

  • Winds becoming southwest 20 km/h, gusting to 40 km/h

• Afternoon:

  • 40% chance of showers, risk of a thunderstorm

  • Winds increasing to 40 km/h gusting to 70–90 km/h

• High: 25°C

• Humidex: 28

• UV Index: 4 (moderate)

Tonight (Sunday Night)

• Partly cloudy with a 40% chance of showers and continued risk of thunderstorms early in the evening

• Winds southwest 40 km/h gusting to 70, becoming northwest 20 gusting to 40 before morning

• Low: 8°C

Monday, October 6

• A mix of sun and cloud, becoming cooler and calmer

• Winds northwest 20 km/h, gusting to 40, becoming light by midday

• High: 15°C

• UV Index: 4 (moderate)

Monday Night:

• Clear skies

• Low: +4°C

Tuesday, October 7

• A mix of sun and cloud, with a 40% chance of showers

• Much cooler, with a high of just 12°C

Tuesday Night:

• Clear and cold, with low of -2°C

• Frost risk returns — gardeners take note

🧥 Wardrobe & Safety Tips

Today (Sunday):

• Dress in summer layers, but secure outdoor items and stay alert for thunderstorms and strong gusts.

• Avoid forested or open areas during storms.

Tonight:

• A windbreaker or waterproof shell may be useful as the cold front sweeps in.

Monday & Tuesday:

• Fall layers return. Keep jackets, scarves, and warmer clothing handy by Tuesday morning.

🌬️ Wind Alert: What You Should Do

• Avoid parking under trees or near loose signage

• Secure patio furniture, garbage bins, and decorations

• Delay boating, cycling, or hiking in exposed areas

• Stay updated on wind warnings from Environment Canada

Weather Trivia

Did you know?
Thunder Bay’s average high for October 5 is around 13°C — today’s high of 25°C with humidex 28 is a remarkable deviation from normal. Strong fall cold fronts like this can trigger sudden wind surges and even out-of-season thunderstorms, particularly when warm, moist air meets cooler, dry Arctic air aloft — a classic setup unfolding today.

Be storm-smart today and enjoy the warmth while it lasts — cooler, calmer weather returns Monday. Stay with the NetNewsLedger Weather Desk for the latest alerts and updates.