Other facts from our historical weather data: Which is the warmest month in Llansantffraid Glyn Ceiriog? July has an average maximum temperature of 20°C (68°F) and is the warmest month of the year. Which is the coldest month in Llansantffraid Glyn Ceiriog? The coldest month is February with an average maximum temperature of 8°C (46°F). Which is the wettest month in Llansantffraid Glyn Ceiriog? December tops the wettest month list with 87mm (3.4 in) of rainfall. Which is the driest month in Llansantffraid Glyn Ceiriog? March is the driest month with 69mm (2.7 in) of precipitation. Which is the sunniest month in Llansantffraid Glyn Ceiriog? May is the sunniest month with an average of 169 hours of sunshine. No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.