Thunder Bay – Weather – While Spring officially arrived in Thunder Bay today but the weather is not rushing to match the calendar. The city started the day under partly cloudy skies with a sharp morning chill, and while temperatures are expected to climb above freezing this afternoon, snow remains in the forecast for Saturday.
This is a classic Northwestern Ontario spring transition, with milder air trying to move in while winter still holds on.
Today’s Weather Overview
Current Conditions
As of 9:00 AM EDT on Friday, March 20, Thunder Bay was reporting partly cloudy skies and a temperature of -3.4°C. The humidity was high at 91 percent, helping give the air a damp, raw feel. Winds from the southwest at 9 km/h pushed the wind chill down to -7, making it feel noticeably colder than the thermometer suggests.
Barometric pressure was 101.1 kPa and rising, a sign of some short-term stabilization in the atmosphere. Visibility was 24 km, which is fairly good, although the early forecast still carried a 30 percent chance of flurries and a risk of freezing drizzle this morning.
For the rest of Friday, Thunder Bay will stay mainly cloudy, with light winds up to 15 km/h and a high of 5°C. That means the city will get a brief taste of spring warmth, even if it comes under grey skies.
Tomorrow’s Forecast
Expected Conditions
Tonight will remain cloudy, with winds up to 15 km/h and a low of -3°C. The overnight wind chill will make it feel closer to -7.
Saturday, March 21 turns more wintry again. Environment Canada is calling for periods of snow, with about 5 cm expected through the day. The high will reach 0°C, and winds will become northeast at 20 km/h late in the afternoon. The morning will begin with a wind chill near -6, so it will feel like winter despite the spring date on the calendar.
Saturday night will stay cloudy, with a 30 percent chance of flurries and a low of -9°C.
Sunday, March 22 brings a mix of sun and cloud, along with a 30 percent chance of flurries. The high will be -1°C, followed by cloudy periods Sunday night and a low of -11°C.
Monday, March 23 looks brighter, with sunny skies and a high of 1°C. Monday night turns colder again, with a 40 percent chance of flurries and a low of -6°C.
Wardrobe Recommendations
Friday still calls for layered clothing. A winter jacket or heavier spring coat is a smart choice for the morning, along with gloves for anyone heading out early while the wind chill sits near -7. Waterproof footwear is a good idea as temperatures rise and surfaces become wet or slushy.
For Saturday, winter gear will still be the best option. A warm coat, boots with traction, and a hat will help you stay comfortable in the snow and colder northeast wind. Thunder Bay may be on the first day of spring, but the wardrobe still says late winter.
Weather Trivia
In Thunder Bay, the first day of spring often looks a lot more like March than May. It is not unusual for snow to fall well into the season, and some of the city’s most changeable weather often arrives during late March, when milder air and lingering cold air battle for control.
