Castletown Temperature by Month
Castletown, Isle of Man, United Kingdom has an average annual maximum temperature of 13°C (55°F), with moderate seasonal shifts ranging from 9°C (48°F) in February to 17°C (63°F) in August. Below you'll find a full monthly breakdown and a comparison with cities worldwide.
Castletown Monthly Temperatures
In Castletown, seasonal changes bring about a moderate variation in temperatures. Nighttime lows range from 14°C (57°F) in August to 6°C (43°F) in February.
The chart below illustrates the average maximum day and minimum night temperatures in Castletown by month:
The coldest point of the day usually falls between 4 AM and 6 AM, with temperatures peaking around 3 PM.
The chart below shows the average temperature throughout the year:
Temperature: Castletown vs the United Kingdom
The map below shows the annual temperature across the United Kingdom. You can also select individual months if you want to compare a specific time of year.
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moderate
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Castletown vs World: Temperature Compared
Castletown's average annual maximum temperature is 13°C (55°F). To put that in context, here's how it compares to a few well-known destinations:
Barcelona, Spain has an annual average of around 21°C (70°F), with warm summers and mild, fairly short winters.
Queenstown, New Zealand averages 10°C (50°F) annually — remember seasons are flipped, so its coldest months fall in June and July.
Chicago, USA averages 15°C (59°F) annually — known for extreme seasonal swings, from bitterly cold winters to warm summers.
Adelaide, Australia averages 21°C (70°F) a year, with warm summers, mild winters, and relatively low rainfall year-round.
Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.
The readings come from a range of sources — land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.
Seasonal temperature shifts influence more than just how warm it feels — they also drive changes in rainfall, cloud cover, and wind patterns throughout the year.
Warmer air holds more moisture, which tends to mean heavier or more frequent rain during the warmer months. When temperatures drop in winter, any precipitation that does fall is more likely to come as snow or sleet, though in Castletown this rarely lasts long on the ground.
For more on Castletown's weather — including monthly rainfall, sunshine hours, and humidity — visit our Castletown climate page.
