Thunder Bay weather
Loading live data…Cloudy,cooler tomorrow
Env. Canada, the European and the American model put Thunder Bay's high today between 18° and 20°, a 2° split. Tomorrow looks cloudy around 15°, with a 45% chance of rain.
CheckWeather.io on iPhoneFree. No ads, no account.Thunder Bay weather in numbers
measured normals and 10 years of recorded weatherThunder Bay swings 34°C across the year, from 22°C highs in July to -12°C lows in February, and April is usually the wettest month in a year that brings about 706 mm of precipitation. Over 10 years of recorded weather it averages 18 days a year at 25°C or above, 1 of them at 30°C or above, 169 frost nights, and rain on 109 days.
Day counts are from the ERA5 reanalysis for Thunder Bay’s grid square, 2016 to 2025, counted the same way for every city so the numbers compare. A reanalysis square is an area, not a weather station, so it is good for counting days and not for a single day’s record.
The weather map: all three models at once
Env. Canada, European, American side by side around Thunder Bay and nearby towns.Live rain radar →Thunder Bay hourly forecast: next 14 hours
consensus of the three modelsRain in the next 24 hours, model by model
each model's own hourly precipitation, side by sideLoading the three models…
Thunder Bay 10-day forecast, out to 14 days
where the models agree, and where they splitThunder Bay, Ontario is at its warmest in Jul (average highs near 22°C) and coldest in Feb (lows around -12°C), with roughly 706 mm of precipitation across the year. Below, compare what Env. Canada, European, American forecast for Thunder Bay right now, and see exactly where they disagree.
We grade every model against the weather that actually happened, so you can see which forecast model is most accurate in Canada before you trust any single number.
Thunder Bay climate by month
average daytime high and overnight low across a typical yearWhich forecast is most accurate in Thunder Bay?
CheckWeather Score, graded against the weather that actually happened
The CheckWeather Score blends temperature, wind and rain accuracy, each measured against ERA5 (the recorded weather) over the last 30 days across 1304 cities. Lower error means a higher score. See which forecast model is most accurate in Canada, how we measure forecast accuracy, or which model each weather app uses.
What do you think of the forecasts?
your vote countsThe accuracy above is the measured record. This is your opinion: which forecast service do you trust most in Canada? Give each 1 to 5 stars.
One vote per service. Anonymous: we store no personal data, only a one-way hash of your connection for a day to stop double votes.
Where the models disagree
temperature and rain, judged separatelyThe models often agree on temperature and still split on rain, and rain is usually what decides whether a plan survives. A wide rain range means the shower is genuinely uncertain, not that the forecast is wrong.