Cool Calm in the Bay as March Winds Down
Thunder Bay, ON – Sunday, March 30, 2025 – It’s a cool and cloudy morning in Thunder Bay as March tiptoes toward its grand finale. While other parts of the province are sliding on ice, the city is enjoying a far more composed weather situation — just cold enough to remind you that winter still lingers, but without the drama.
As of 6:00 AM at Thunder Bay Airport, the temperature is -3.1°C, and skies are cloudy with excellent visibility of 24 km. Winds are light from the north-northeast at 6 km/h, producing a modest wind chill of -6°C. The humidity is low at 44%, and the barometric pressure is 102.0 kPa and falling, hinting at a mild system shift — but nothing too worrisome.
Today: Mainly Cloudy and Mild, with Light Winds and a Touch of Sun
The clouds will hang around for much of the day, but east winds picking up to 20 km/h and gusting to 40 km/h will bring some movement in the atmosphere. The high reaches a modest +1°C, which isn’t tropical, but it’s headed in the right direction. This morning’s wind chill near -10°C might make your nose crinkle, but it improves noticeably by afternoon. The UV index sits at 4, so don’t forget your sunglasses and sunscreen — yes, even when it’s cloudy. Science is wild like that.
Tonight into Monday: Clearer Skies, Colder Nights
As the evening progresses, skies will become partly cloudy, and winds will shift to the north at 20 km/h, easing off late. The temperature will drop to -10°C overnight, and the wind chill will make it feel closer to -14°C — a crisp reminder that April hasn’t officially sprung yet.
Monday starts with sunshine that becomes a mix of sun and cloud in the afternoon, as northwest winds at 20 km/h gusting to 40 arrive. The high will be a mild +2°C, but the morning will be sharp, with a wind chill near -18°C — so bring your layers and maybe a hot beverage. Monday night clears out nicely but gets downright frigid with a low of -15°C.
Tuesday remains sunny during the day with a high of +1°C, but cloudy periods return at night with a 30% chance of flurries and a low of -8°C.
What to Wear: Spring Dreams, Winter Layers
It’s not quite time for spring jackets or lightweight fashion. You’ll want a good insulated coat, wind-resistant gear, gloves, and a toque today — especially in the morning and evening. Afternoons offer a gentle reprieve, so layers you can shed are a smart move.
Thunder Bay’s Weather Flashback
The warmest March 30th in Thunder Bay history hit 15.6°C in 1998, while the chilliest fell to a shivering -29.4°C in 1964. Today’s forecast might not be record-breaking, but it’s definitely leaning toward the kinder end of the scale.
Thunder Bay Weather Trivia
Did you know that Thunder Bay is one of Canada’s sunniest cities in winter? Despite its snowy reputation, the city racks up more sunshine hours than many of its Ontario peers, especially in late winter and early spring. Now if we could just get that sun to come with warmth!
