Mild
Average highs are around 24°C, so days are mild rather than hot.
Weather Guide
Thunder Bay, Ontario, Canada Average Monthly Weather
Weather score33Poor annual avg
Best months: July, August, June
Across the year, average daytime temperatures are around 8°C, sunshine averages 5.8h per day, and rainfall totals about 715mm. Sea temperatures average 6°C across the year.
Annual weather
Annual averages
Temp
8°C
Rain
715mm
Annual total
Sun
5.8h
Sea
6°C
Weather score
33
Poor avg
Seasonal climate calendar
TemperatureTemp
RainRain
SunSun
SwimSwim
Weather scoreWeather score
Trip feel
Showers
Rainfall averages 82mm, so some wet days are possible.
Bright
Sunshine averages 9.4h per day, so bright days are a strong part of the month.
Cool sea
Sea temperatures average 9°C, so the water can feel cool.
Map
Weather map
Compare Thunder Bay, Ontario, Canada with nearby places by weather score, rain, sun, temperature, and swim conditions.
Temperature
July24°C average high
July is one of Thunder Bay's warmest months, with daytime heat above the yearly average.
Warmest monthsJune to September
This stretch sets the upper range for average daytime heat.
Rain
July82mm average rain
July is one of Thunder Bay's wettest months, so rain is likely to be a major planning factor.
Driest monthsJanuary to April and November to December
This is the drier part of the year, when outdoor plans usually need less weather flexibility.
Sun
July9.4 hours average sun
July is one of Thunder Bay's sunniest months, with some of the strongest bright-day conditions in the yearly averages.
Brightest monthsMay to August
This stretch has the strongest sunshine in the monthly averages.
Sea temperature
July9°C average sea
July is close to Thunder Bay's yearly sea-temperature average, so swimming comfort is fairly typical.
Warmest seaAugust to September
Sea temperatures are usually near 16°C in this stretch, so swimming comfort is at its strongest.
Weather score
July53 weather score
July is one of Thunder Bay's best weather-score months, combining the strongest overall balance in the yearly averages.
Best weather monthsJuly to August
These months have the strongest weather score in the monthly averages.
