Johnston Temperature by Month
Johnston, Dyfed, United Kingdom has an average annual maximum temperature of 14°C (57°F), with moderate seasonal shifts ranging from 10°C (50°F) in February to 19°C (66°F) in August. Below you'll find a full monthly breakdown and a comparison with cities worldwide.
Johnston Monthly Temperatures
The moderate changes in the climate in Johnston ensure gradual weather shifts through each season. At night, temperatures drop to between 14°C (57°F) and 5°C (41°F) depending on the time of year.
The chart below illustrates the average maximum day and minimum night temperatures in Johnston 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: Johnston 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.
very warm
warm
pleasant
moderate
cold
very cold
Johnston vs World: Temperature Compared
Johnston'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:
Barcelona, Spain has an annual average of around 21°C (70°F), with warm summers and mild, fairly short winters.
Toronto, Canada averages 13°C (55°F) annually, with cold snowy winters balanced by genuinely warm summers.
Seoul, South Korea averages 18°C (64°F) a year, with four clear seasons, cold winters, and hot humid summers.
Perth, Australia averages 25°C (77°F) annually, with a classic Mediterranean climate — hot dry summers and mild wet winters.
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 Johnston this rarely lasts long on the ground.
For more on Johnston's weather — including monthly rainfall, sunshine hours, and humidity — visit our Johnston climate page.