Other facts from our historical weather data: Which is the warmest month in Rhuddlan? 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 Rhuddlan? The coldest month is February with an average maximum temperature of 9°C (48°F). Which is the wettest month in Rhuddlan? December tops the wettest month list with 95mm (3.7 in) of rainfall. Which is the driest month in Rhuddlan? March is the driest month with 71mm (2.8 in) of precipitation. Which is the sunniest month in Rhuddlan? May is the sunniest month with an average of 209 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.