Other facts from our historical weather data: Which months have the greatest rainfall in Seyðisfjörður? Most rainfall (rainy season) is seen in January and October. Which is the warmest month in Seyðisfjörður? July has an average maximum temperature of 14°C (57°F) and is the warmest month of the year. Which is the coldest month in Seyðisfjörður? The coldest month is December with an average maximum temperature of 1°C (34°F). Which is the wettest month in Seyðisfjörður? January tops the wettest month list with 159mm (6.3 in) of rainfall. Which is the driest month in Seyðisfjörður? June is the driest month with 73mm (2.9 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.