Thunder Bay – Weather Desk – It feels a lot more like mid-January this morning than St. Patricks’s Day. Thunder Bay is waking up to a hard March cold snap. Even with only a light west breeze, the wind chill is -28 this morning, and there’s a risk of frostbite for anyone outdoors for more than a short time.
The good news: sunshine helps temperatures rebound to -8°C today. The next change arrives tonight as light snow develops, followed by more organized snow Wednesday and a milder trend later in the week.
Current Conditions (Observed 7:00 AM EDT, Tuesday March 17, 2026)
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Condition: Mostly cloudy
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Temperature: -21.4°C
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Wind: W 8 km/h
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Wind Chill: -28
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Pressure: 102.0 kPa (rising)
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Humidity: 60%
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Dew Point: -27.2°C
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Visibility: 24 km
Today (Tuesday)
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Sky: Sunny, becoming a mix of sun and cloud this afternoon
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Wind: Becoming west 20 km/h late this morning
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High: -8°C
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Wind Chill: -28 this morning, improving to -12 this afternoon
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UV Index: 3 (Moderate)
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Main concern: Frostbite risk this morning in the extreme wind chill
Expected Conditions (Next Three Days)
Tonight (Tuesday Night)
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Sky: Mainly cloudy
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Snow: Periods of light snow beginning late this evening
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Wind: Up to 15 km/h
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Low: -11°C, with temperature rising to -8°C by morning
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Wind Chill: Near -15 this evening
Wednesday, March 18
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Sky: Cloudy
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Snow: Periods of snow beginning in the afternoon
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Wind: West 20 km/h, becoming light late morning
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High: -1°C
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Wind Chill: -17 in the morning, near -3 in the afternoon
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Night: Cloudy with 40% chance of flurries, low -7°C
Thursday, March 19
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Day: Sunny, high +1°C
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Night: Periods of snow or rain, low -1°C
Wardrobe Recommendations
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This morning: Dress for wind chill -28—insulated parka, warm mitts, toque, and a neck warmer/balaclava. Keep skin covered if you’ll be outside.
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This afternoon: Still winter-cold at -8°C, but more manageable. Layers work best so you can adjust as the sun helps.
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Tonight: With light snow developing, wear boots with good traction—fresh snow can hide slick patches.
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Wednesday into Thursday: Expect changing conditions: colder morning chills Wednesday, then a milder push Thursday with a possible snow/rain mix at night. Waterproof outerwear may be handy later.
Weather Trivia
A “warming” day in winter can still start dangerously cold. Even small winds can create harsh wind chills because moving air strips away the thin layer of warmth around your skin—one reason frostbite risk can be high on sunny, cold mornings.
Summary
Thunder Bay weather outlook for Tuesday, March 17, 2026: -21°C this morning with wind chill -28 and frostbite risk. Sunny today with a high of -8°C. Light snow develops late tonight, followed by periods of snow Wednesday afternoon and a milder trend Thursday with a high of +1°C.
