A Chilly Yet Clear Start for Thunder Bay

Thunder Bay – Weather – Thunder Bay wakes up to a brisk and crisp Tuesday morning, with clear skies and nearly calm winds greeting early risers. A gentle fog lingers, but it’s set to clear soon as sunshine takes over.

As we move through the day, warm summer-like temperatures will return, making for a pleasant and bright afternoon before a shift in conditions later tonight.

Morning Weather Overview

Current Conditions – 7:00 AM EDT, Thunder Bay Airport

• Temperature: 5.0°C

• Condition: Clear

• Wind: WNW at 7 km/h

• Barometric Pressure: 102.2 kPa (Rising)

• Humidity: 99%

• Dew Point: 4.9°C

• Visibility: 32 km

Thunder Bay is currently experiencing calm and clear weather, with a slight chill in the air thanks to high humidity and low morning temperatures. The barometer is rising, hinting at improving conditions through the day.

Today’s Forecast – Tuesday, August 26

• Daytime: Sunny skies will dominate after morning fog patches lift. Expect the wind to pick up from the west at 20 km/h later in the morning.

• High: 23°C

• UV Index: 6 – High (sun protection recommended)

• Tonight: Cloud cover will increase overnight with a 40% chance of showers developing before morning.

• Low: 11°C

Forecast for Rest of the Week

Wednesday, August 27

• Day: Cloudy with a 60% chance of showers, and the risk of an afternoon thunderstorm. Humidex values will make it feel slightly warmer.

  • High: 21°C (Humidex: 25)

  • UV Index: 2 – Low

• Night: Cloudy periods persist with a 40% chance of showers.

  • Low: 11°C

Thursday, August 28

• Day: Clear skies return with sunshine dominating the day.

  • High: 20°C

• Night: Clear and cool.

  • Low: 9°C

Friday, August 29

• Day: Another sunny day with warmer temperatures.

  • High: 22°C

• Night: Clear skies continue.

  • Low: 10°C

Wardrobe Recommendations

• Today: Start the morning with a light jacket or sweater to keep warm in the early chill. By afternoon, short sleeves or light layers will be comfortable.

• Tomorrow: Carry a light rain jacket or umbrella due to expected showers and potential thunderstorms. Waterproof footwear may also be a good idea.

• Thursday & Friday: Dress in layers for cool mornings and warm afternoons. Sunglasses and sunscreen are recommended with the return of sunny skies.

Weather Trivia

Did You Know?
Thunder Bay holds the record for the lowest August temperature in Ontario, hitting a chilling –1.1°C on August 28, 1982. Late August can bring surprising temperature swings—something residents are no strangers to!