Thunder Bay – Local Weather – After a night of thunder and rain, residents are waking up to calmer conditions. However, there is a Fog Advisory in effect this morning for Thunder Bay, with near-zero visibility creating hazardous travel conditions across the city.

Combined with 100% humidity, still air, and a high likelihood of showers and thunderstorms by this afternoon, the city faces a day of unsettled weather.

Looking ahead, smoke is expected to return Thursday, accompanied by clearing skies and a brief break before more showers move in for the weekend.

Today’s Weather Overview

Current Conditions (as of 8:19 AM EDT):

• Temperature: 18.0°C

• Dew Point: 18.0°C

• Humidity: 100%

• Wind: East at 12 km/h

• Pressure: 101.2 kPa (falling)

• Visibility: 0.4 km

• Condition: Fog

Dense fog continues to blanket the city, limiting visibility to just 400 metres or less in many locations. Conditions are expected to gradually improve by mid-morning, but a 60% chance of showers and a risk of thunderstorms looms for the afternoon.

Extended Weather Forecast

Expected Conditions (July 24 – July 27):

Thursday, July 24:

• Day: Morning clearing, followed by local wildfire smoke.

  • High: 26°C

  • Humidex: 31

  • UV Index: 8 (Very High)

• Night: Cloudy periods.

  • Low: 13°C

Friday, July 25:

• Day: A mix of sun and cloud with 30% chance of showers.

  • High: 25°C

• Night: Cloudy periods.

  • Low: 13°C

Saturday, July 26:

• Day: A mix of sun and cloud with 30% chance of showers.

  • High: 25°C

• Night: Cloudy periods with 30% chance of showers.

  • Low: 15°C

Sunday, July 27:

• Day: Similar pattern continues with sun/cloud mix and 30% chance of showers.

  • High: 26°C

• Night: Cloudy.

  • Low: 16°C

The week ahead offers brief sunny breaks, but precipitation remains in the picture each day. Smoke on Thursday may cause temporary air quality concerns.

Wardrobe Recommendations

Get dressed and plan accordingly:

• Today (Fog + Thunderstorms):

  • Wear light, moisture-wicking clothing but carry a waterproof jacket or umbrella.

  • Use caution while travelling due to fog—avoid driving if possible.

  • Appropriate footwear for wet surfaces is advised.

• Thursday (Smoke + Sun):

  • Choose breathable summer attire with UV protection.

  • If sensitive to air quality, consider an N95 mask when outdoors.

  • Use sunscreen and sunglasses—the UV index is very high.

• Friday through Sunday:

  • Keep light rain gear on standby.

  • Flexible layering will be helpful as conditions change frequently.

Weather Trivia

Did you know?
Thunder Bay’s location near Lake Superior makes it especially prone to radiation fog during summer months. When humid air cools overnight under clear or lightly overcast skies, dense fog can form quickly and linger into the late morning. This is one of the key reasons fog advisories are relatively common in the city during July and August.