Chilly Start Turns Into a Sunny Saturday – But Showers and Thunder Loom for Sunday

THUNDER BAY – A crisp and clear Saturday morning marks the start of the weekend in Thunder Bay, but residents should prepare for a quick change in weather patterns. While today offers mostly sunny skies, showers and even a risk of thunderstorms will roll in by Sunday, keeping umbrellas in high demand through early next week.

Today’s Weather Overview

Current Conditions

At 7:00 AM EDT, the temperature at Thunder Bay Airport is a brisk 3.8°C under mainly sunny skies. With 100% humidity and light westerly winds at 5 km/h, the air feels cool and still. Visibility remains strong at 19 km, and barometric pressure is 101.6 kPa, though it is falling as a low-pressure system approaches.

Expect a sunny morning with increasing clouds later in the afternoon, leading to a 30% chance of showers by evening. The high will reach 19°C, and the UV index is 7 (high) — sun protection is essential, especially in the midday hours.

Tomorrow’s Forecast

Sunday, June 8

• Morning to Afternoon: Expect showers throughout the day with a risk of thunderstorms developing in the afternoon.

• Rainfall Amount: 10 to 15 mm locally.

• High: 14°C

• UV Index: 3 or moderate

• Night: Cloudy, with a 60% chance of lingering showers, low of 8°C.

Monday, June 9

• Day: Continued cloudy skies with a 40% chance of showers.

• High: 15°C

• Night: Cloudy periods with 40% chance of showers, low of 10°C.

Tuesday, June 10

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

• High: 21°C

• Night: Cloudy periods and a 40% chance of showers, low of 11°C.

Wardrobe Recommendations

• Saturday: Start with warm layers for the early chill, and transition to lighter clothing by the afternoon. Keep a light jacket or umbrella handy for the chance of showers later today.

• Sunday: It’s a wet weather day — waterproof clothing and boots are strongly recommended, especially if you’ll be outdoors.

• Monday and Tuesday: The unsettled weather continues, so stay prepared with layered outfits and rain protection.

Weather Trivia

Did You Know?
Thunder Bay holds the record for one of the largest single-day temperature swings in Ontario — jumping over 30°C in a 24-hour period during early spring! The city’s location near Lake Superior means rapid changes in wind direction and lake effects can lead to dramatic and unpredictable shifts in the weather.