Thunder Bay – WEATHER – As Thunder Bay awakens under a mostly cloudy sky this Thursday morning, conditions remain calm but with potential changes on the horizon. A mild 12°C start to the day transitions into an afternoon where scattered showers and even the risk of a thunderstorm may emerge.

Looking ahead, residents can expect warmer temperatures and a mix of sun and cloud as we head into the weekend.

Today’s Weather Overview

Current Conditions

As of 7:00 AM EDT at Thunder Bay Airport:

• Temperature: 11.8°C

• Condition: Mostly Cloudy

• Wind: WNW at 5 km/h

• Humidity: 95%

• Dew Point: 11.0°C

• Barometric Pressure: 102.0 kPa, falling

• Visibility: 32 km

Morning fog patches are clearing, and by midday, southeast winds will pick up to 20 km/h with gusts reaching 40 km/h. The high today will reach 19°C, accompanied by a UV index of 7, which is considered high—sun protection is recommended during breaks in the clouds.

There is a 40% chance of showers late this afternoon, along with the risk of a thunderstorm.

Tonight

Expect mainly cloudy skies with continued 40% chance of showers early this evening and overnight, again with the risk of a thunderstorm. Winds will ease after sunset, dropping from gusty southeast conditions to calm. The low will settle around 14°C.

Tomorrow’s Forecast

Expected Conditions

Friday, August 15:

• A warm, humid day is in store. Mainly cloudy, with a 40% chance of morning showers and thunderstorms.

• Winds shift to southwest at 20 km/h, gusting to 40 km/h near noon.

• Daytime high of 25°C, with a humidex of 30, making it feel noticeably warmer.

• UV index remains high at 7.

• Friday Night: Cloudy periods continue, with a 40% chance of showers. Low of 13°C.

Saturday, August 16:

• A beautiful start to the weekend with sunny skies and a high of 25°C.

• Saturday Night: Clear and cooler. Low of 8°C.

Sunday, August 17:

• Another sunny day, though a bit cooler with a high of 19°C.

• Sunday Night: Cloudy periods develop with a 30% chance of showers. Low of 7°C.

Wardrobe Recommendations

• Today: Light layers and a waterproof jacket or umbrella are smart choices, especially in the afternoon when showers or thunderstorms could roll in. Sun protection is advisable during breaks in the cloud.

• Friday: Dress for warmth and humidity—breathable fabrics like cotton or moisture-wicking materials will help. A hat and sunscreen are also recommended.

• Saturday/Sunday: Ideal for outdoor plans. Shorts and t-shirts during the day, but pack a sweater or light jacket for the cooler evenings.

Weather Trivia

Did you know? Thunder Bay’s record high for August 14 is 32.5°C, set back in 1983. While we’re not reaching those extremes today, the warm-up heading into the weekend is typical of late-summer swings seen in Northwestern Ontario.