Other facts from our historical weather data: Which is the warmest month in Shetland? August has an average maximum temperature of 15°C (59°F) and is the warmest month of the year. Which is the coldest month in Shetland? The coldest month is February with an average maximum temperature of 8°C (46°F). Which is the wettest month in Shetland? January tops the wettest month list with 136mm (5.4 in) of rainfall. Which is the driest month in Shetland? May is the driest month with 52mm (2 in) of precipitation. Which is the sunniest month in Shetland? 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.