June 25, 2026: Thunder Bay Weather Focus — Chilly Morning Start Before Sun, Clouds, and Afternoon Shower Risk
THUNDER BAY – WEATHER – Thunder Bay begins Thursday with a chilly early-summer feel. The morning started near 7°C, and at 7:00 AM EDT, the temperature at Thunder Bay Airport was still only 8.7°C under mainly sunny skies.
While the day starts bright and calm, clouds will build, and the forecast includes a chance of showers and a risk of thunderstorms this afternoon. Our live weather check also points to sunny conditions early in the day, with temperatures rising into the low 20s.
Today’s Weather Overview
Current Conditions
At 7:00 AM EDT at Thunder Bay Airport, conditions were mainly sunny with a temperature of 8.7°C. The dew point was 8.5°C, and humidity was very high at 99 percent, giving the morning a damp, cool edge.
Winds were light from the west-southwest at 5 km/h, visibility was excellent at 32 km, and the barometric pressure was 101.6 kPa and rising.
Today’s forecast calls for skies to be clear early this morning, then becoming a mix of sun and cloud. There is a 40 percent chance of showers this afternoon, along with a risk of a thunderstorm. Fog patches will dissipate this morning. The high will reach 21°C, and the UV index is 7, or high.
Extended Weather Forecast
Expected Conditions
Tonight: Thunder Bay will see partly cloudy skies with a 40 percent chance of showers this evening. There is also a risk of a thunderstorm this evening. Skies become clear overnight, with fog patches developing after midnight and a low near 10°C.
Friday, June 26: Friday starts sunny through the morning and early afternoon, then becomes a mix of sun and cloudwith a 30 percent chance of showers in the afternoon. There is also a risk of a thunderstorm. Morning fog patches will dissipate. The high will reach 24°C, with a UV index of 7, or high.
Friday Night: Cloudy periods are expected, with a low of 9°C.
Saturday, June 27: A pleasant summer day is expected, with a mix of sun and cloud and a high of 26°C. Saturday night brings cloudy periods and a low of 11°C.
Sunday, June 28: The unsettled pattern returns with a mix of sun and cloud and a 40 percent chance of showers. The high will be 25°C. Sunday night turns cloudier, with a 60 percent chance of showers or thunderstorms and a low of 15°C.
Wardrobe Recommendations
A light jacket, hoodie, or sweater is a good choice for the morning, especially with temperatures starting in the single digits. By afternoon, lighter clothing should be comfortable as Thunder Bay warms into the low 20s.
Keep a rain jacket or umbrella nearby for the afternoon and evening shower risk. With the UV index at 7, sunglasses, sunscreen, and a hat are recommended during sunny breaks.
Weather Trivia
Thunder Bay often sees chilly June mornings because of its location near Lake Superior. The lake warms slowly through spring and early summer, which can help keep early-day temperatures cooler even when afternoon highs climb into comfortable summer territory.
