Climate Insights for Caerphilly

The climate in Caerphilly is temperate. The average annual temperature is 11°C and approximately 1116mm of precipitation falls per year. Caerphilly receives a notable amount of rainfall throughout the year, including during its driest month. Caerphilly is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: July, August, June. The coldest months are January, February, March, when temperatures can drop to 3°C. Light snow can occur between January and December.

Caerphilly sees moderate temperature variation throughout the year, ranging from 3°C to 20°C. July is the warmest month, though highs remain moderate at 20°C with a mean of 17°C. January is the coolest month, with minimum temperatures around 3°C and an average of 6°C. Daily temperature variation is modest, with an average difference of 5°C between highs and lows. The sharpest temperature change occurs between October and November, with a 3°C shift in average temperatures.

Caerphilly is a moderately rainy area, receiving approximately 1116mm of precipitation annually, which averages out to around 93mm per month. The wettest month is October, averaging 124mm of rainfall. December and November also tend to see above-average precipitation. The driest month is April, with just 63mm. That's 61mm less than October, the wettest month. Rainfall is relatively evenly distributed throughout the year, so there is no pronounced dry or wet season to plan around. Light snowfall can occur between January and December, totalling around 10cm annually. March is the snowiest month with approximately 5cm.

Caerphilly is mildly breezy, with an average annual wind speed of 17km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is February, averaging 20km/h, noticeable enough to affect lighter outdoor activities. The calmest conditions occur in May, with average winds dropping to 14km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 6km/h gap between the calmest and windiest months. Wind tends to be stronger during winter months, driven by seasonal pressure systems. The seasonal averages break down to 19km/h in winter, 16km/h in spring, 15km/h in summer, 17km/h in autumn.

It is currently summer in Caerphilly, which began on June 21, 2026. Caerphilly is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in July at around 20°C, while the coldest stretch bottoms out in January near 3°C. Autumn is next, beginning on September 23, 2026 (7 days from now).

The best time to visit Caerphilly is during June, July and August, when the weather is most comfortable for travellers. During these months, average temperatures hover around 16°C with modest rainfall averaging 76mm per month. By contrast, January can be quite cold with temperatures dropping to 3°C. Despite being the best months overall, some rain is still likely. Pack a waterproof layer and plan a mix of indoor and outdoor activities.

The table below shows monthly climate averages for Caerphilly based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.