Climate Insights for Llantwit Major

The climate in Llantwit Major is temperate. The average annual temperature is 11°C and approximately 1180mm of precipitation falls per year. Llantwit Major receives a notable amount of rainfall throughout the year, including during its driest month. Llantwit Major 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 February, January, March, when temperatures can drop to 4°C. Light snow can occur between January and December.

Llantwit Major sees moderate temperature variation throughout the year, ranging from 4°C to 19°C. July is the warmest month, though highs remain moderate at 19°C with a mean of 17°C. February is the coolest month, with minimum temperatures around 4°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 April and May, with a 3°C shift in average temperatures.

Llantwit Major is a moderately rainy area, receiving approximately 1180mm of precipitation annually, which averages out to around 98mm per month. The wettest month is December, averaging 135mm of rainfall. October and November also tend to see above-average precipitation. The driest month is May, with just 54mm. That's 81mm less than December, 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 11cm annually. March is the snowiest month with approximately 6cm.

Llantwit Major is relatively calm, with an average annual wind speed of 5km/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 6km/h, though still comfortable for most outdoor activities. The calmest conditions occur in May, with average winds dropping to 4km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 2km/h gap between the calmest and windiest months.

It is currently summer in Llantwit Major, which began on June 21, 2026. Llantwit Major 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 19°C, while the coldest stretch bottoms out in February near 4°C. Autumn is next, beginning on September 23, 2026 — 93 days from now.

The best time to visit Llantwit Major is during June and July, when the weather is most comfortable for travellers. During these months, average temperatures hover around 16°C with modest rainfall averaging 79mm per month. By contrast, February can be quite cold with temperatures dropping to 4°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 Llantwit Major 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.