Other facts from our historical weather data: Which is the warmest month in Ennis? July has an average maximum temperature of 19°C (66°F) and is the warmest month of the year. Which is the coldest month in Ennis? The coldest month is February with an average maximum temperature of 10°C (50°F). Which is the wettest month in Ennis? December tops the wettest month list with 118mm (4.6 in) of rainfall. Which is the driest month in Ennis? May is the driest month with 84mm (3.3 in) of precipitation. Which is the sunniest month in Ennis? May is the sunniest month with an average of 182 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.