Plymouth Temperature by Month

The average annual maximum temperature in Plymouth, Cornwall, United Kingdom is 14°C (57°F), with daytime highs ranging from 10°C (50°F) in February to 20°C (68°F) in August. This page covers monthly averages, day-night differences, and how Plymouth compares to cities worldwide.

The climate in Plymouth experiences moderate temperature changes, with mild shifts between seasons. At night, temperatures range from 14°C (57°F) in August to 5°C (41°F) in February.

The chart below illustrates the average maximum day and minimum night temperatures in Plymouth by month:

The coldest point of the day usually falls between 4 AM and 6 AM, with temperatures peaking around 3 PM. August, the city's warmest month, gets 205 hours of sunshine.

The chart below shows the average temperature throughout the year:

Plymouth's average annual maximum temperature is 14°C (57°F). To put that in context, here's how it compares to a few well-known destinations:

Seville, Spain averages 23°C (73°F) a year, one of the warmer cities in Western Europe, with long hot summers.

Reykjavík, Iceland averages 9°C (48°F) a year, mild summers by Icelandic standards, but cold winters and frequent wind.

Boston, USA averages 16°C (61°F) annually, with four distinct seasons and cold winters that rival northern Europe.

Adelaide, Australia averages 21°C (70°F) a year, with warm summers, mild winters, and relatively low rainfall year-round.

Temperature alone doesn't tell the whole story, humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.

In the cooler months, when temperatures drop below 10°C, high humidity makes the cold feel more cutting than it would in dry conditions.

In Plymouth, February is the coolest month, with average highs of 10°C (50°F) and humidity around 84%, considered very high. For a full picture, see our humidity page.

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.

Global average temperatures have risen by around 1.2°C since the pre-industrial era, and the effects are visible across many regions. Winters are milder on average, with fewer frost days and less snow in many parts of the world. Heatwaves are more frequent and more intense, and Europe's summers of 2018, 2019, and 2020 all set records.

Summers are also getting drier in some areas, while winter rainfall has increased in others. This contributies to higher river levels and more flooding. In many countries, spring arrives earlier and autumn lasts longer. It has knock-on effects for wildlife, agriculture, and local ecosystems.

For more on Plymouth's weather, including monthly rainfall, sunshine hours, and humidity, visit our Plymouth climate page.