It’s grilling time in Thunder Bay! THUNDER BAY – WEATHER – Thunder Bay is welcoming Sunday with a fresh, mostly sunny start, featuring calm winds and great visibility. The temperature will rise nicely, moving from 6.1°C early this morning to a predicted high of 21°C, making it a bright late-spring day throughout the city.
Current Conditions
As of 8:00 AM EDT on Sunday, May 31, 2026, conditions at Thunder Bay Airport were mainly sunny with temperatures sitting at 6.1°C. The dew point was measured at 3.0°C and humidity levels were at 81 percent, giving the morning a cool and slightly damp sensation. Winds are gentle from the southwest at 4 km/h, visibility remains strong at 32 km, and the barometric pressure is currently at 102.3 k Pa and decreasing. Even though it’s starting off cool, today’s forecast promises full sunshine with a high reaching up to 21°C. The UV index is notably high at 8, so sun protection will be essential for anyone enjoying time outside.Expected Conditions
Tonight: Skies will stay clear as temperatures dip down to around 4°C. It’s going to be a chilly night especially in lower areas away from the city’s center. Monday, June 1: Another sunny day is expected for Thunder Bay but slightly cooler than Sunday’s warmth. Winds will come from the east at 20 km/h before becoming lighter by early afternoon. The high temperature will reach about 18°C with a low UV index of just 1 indicating low risk. Monday night will also remain clear with lows around 4°C. Tuesday, June 2: More sunshine ahead with highs hitting about 22°C during the day while Tuesday night stays clear dropping down to around 7°C. Wednesday, June 3: A warmer trend begins bringing more unsettled weather patterns into play. Expect a combination of sun and clouds along with a chance of showers sitting around forty percent; the high will reach about 27°C. Wednesday night may bring cloudy skies with an increased likelihood of showers pegged at sixty percent and lows near11°C. A jacket or sweater would be wise for this cool morning as temperatures linger near the cold mark of around six degrees Celsius. By afternoon though, lighter spring clothing should feel just right as it warms up to twenty-one degrees. If you’re making outdoor plans today make sure to pack sunglasses, sunscreen, and wear a hat due to that very high UV index we’ve got going on today. Monday morning is again likely to start off cool around four degrees Celsius so commuters should have something warm handy for their strolls. According to Environment Canada , normal temperatures in Thunder Bay for this time of year usually max out around nineteen degrees Celsius while minimums drop down towards six degrees Celsius. Today’s projected high hitting twenty-one degrees stands slightly above average , whereas tonight’s low hovering near four degrees dips just below typical seasonal norms.Source link
