Thunder Bay begins this Wednesday with a cool, damp feel under mostly cloudy skies. The air is nearly saturated, with humidity sitting at 95%, and fog patches are expected to lift through the morning. While the day will not be a washout, residents should keep an umbrella nearby as scattered showers remain possible.
Today’s Weather Overview
Current Conditions
As of 8:00 AM EDT at Thunder Bay Airport, the temperature is 8.0°C, with a dew point of 7.3°C, making the morning feel cool and moist. Winds are light from the north-northeast at 4 km/h, and visibility is good at 32 kilometres.
The barometric pressure is 100.0 kPa and rising, suggesting slightly improving conditions, though cloud cover will remain dominant through the day. Thunder Bay can expect a mainly cloudy Wednesday, with a 30 percent chance of showers this morning. Fog patches will dissipate as the morning progresses.
The daytime high will reach 17°C, with a UV index of 6, rated high.
Tonight, skies will stay cloudy with a 30 percent chance of overnight showers. The low will fall to 8°C.
Tomorrow’s Forecast
Expected Conditions
Thursday will stay unsettled, with mainly cloudy skies and a 40 percent chance of showers. There is also a risk of a thunderstorm in the afternoon, so outdoor plans should include a weather backup.
Winds will become west at 30 km/h late in the morning, before easing later in the afternoon. The high will reach 20°C, and the UV index will climb to 7, also rated high. Thursday night will bring cloudy periods with a 30 percent chance of showers and a low of 9°C.
Friday looks much brighter. Expect sunny skies with a high of 21°C, followed by a clear night and a low of 9°C.
Saturday brings a return to mixed conditions, with sun and cloud and a 40 percent chance of showers. The high will be 21°C, with cloudy periods overnight and a low of 8°C.
Wardrobe Recommendations
A light jacket or sweater is a good choice this morning, especially with temperatures near 8°C and damp air making it feel cooler. Waterproof footwear may be useful in areas where morning fog or light showers leave sidewalks wet.
For the afternoon, dress in layers as temperatures rise toward 17°C. Sunglasses may still be useful during brighter breaks, and sunscreen is recommended despite the cloud cover because the UV index is high.
For Thursday, consider a wind-resistant jacket and keep an umbrella or rain shell handy due to the chance of showers and possible afternoon thunderstorm activity.
Weather Trivia
Thunder Bay’s location on the northwest shore of Lake Superior often plays a major role in its weather. In late spring and early summer, cold lake waters can keep shoreline communities cooler than areas farther inland, especially when winds come off the lake. That lake influence is one reason mornings in Thunder Bay can feel damp and chilly even in June.
Overview: Thunder Bay weather for June 17, 2026: mostly cloudy and cool with a chance of showers, fog lifting this morning, a high of 17°C, and unsettled conditions continuing Thursday.
