Other facts from our historical weather data: Which months have the greatest rainfall in Árnes? Most rainfall (rainy season) is seen in January, February, March, September and December. Which is the warmest month in Árnes? July has an average maximum temperature of 16°C (61°F) and is the warmest month of the year. Which is the coldest month in Árnes? The coldest month is February with an average maximum temperature of 3°C (37°F). Which is the wettest month in Árnes? February tops the wettest month list with 177mm (7 in) of rainfall. Which is the driest month in Árnes? June is the driest month with 102mm (4 in) of precipitation. 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.