A Fresh Start to a Tranquil Weekend Forecast
Thursday: Bright Skies and Cool Breezes
Thunder Bay wakes up under mainly sunny skies this Thursday, June 12, with the temperature sitting at a cool 6.7°C as of 8:00 AM EDT at Thunder Bay Airport. Humidity is high at 85%, and light winds from the west-southwest at 6 km/h make it feel fresh but not frigid. Visibility is excellent at 32 km, and pressure is on the rise at 102.5 kPa — always a reliable indicator of settled weather ahead.
Today will feature a mix of sun and cloud and a high of 15°C — crisp, comfortable, and a great excuse to get outdoors without breaking a sweat. The UV index is a very high 8, so even though the temps are mild, sunscreen and sunglasses are a must if you’re out on the trails, shores, or patios.
Tonight: Stars and Sweaters
Tonight brings partly cloudy skies early, clearing as the evening progresses. Expect a low of 6°C, perfect for an evening walk or cracking open the windows for some cool, clean Lake Superior air. Light layers or a hoodie will be your best friend after sunset.
Friday Through Sunday: Calm, Cool, and Collected
Friday offers clear skies from start to finish, with a high again around 15°C. It’s a great day for yardwork, a shoreline picnic, or just soaking up some much-needed vitamin D. The UV index remains at 8, so don’t let the cool temps fool you — the sun is still in full power mode. The night will be clear and chilly, with a low of just 3°C.
Saturday will warm up nicely with a mix of sun and cloud and a daytime high of 19°C — perfect weather for hiking or heading out to Sleeping Giant. Saturday night stays clear and calm, with a low of 5°C.
Sunday brings more cloud cover but a slightly warmer high of 20°C. While no rain is expected during the day, cloudy periods continue into the night with a low of 7°C.
What to Wear
You’ll need a jacket or cozy layer this morning and again at night through the weekend. During the day, especially under that strong sun, a sweater or long sleeve should suffice. And with the UV index consistently high, don’t forget sunscreen — cool air doesn’t block UV rays!
Historic Weather Trivia
Thunder Bay has a long weather memory, and June 12 is no exception. The record high for this date is a toasty 30.0°C, set in 1977, while the coldest low dipped to 1.0°C in 1985. Today’s forecast sits comfortably in the middle — no heatwaves, no frost warnings, just steady, pleasant spring weather in true North Shore style.
