Other facts from our historical weather data: Which is the warmest month in John O Groats? 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 John O Groats? The coldest month is February with an average maximum temperature of 8°C (46°F). Which is the wettest month in John O Groats? October tops the wettest month list with 120mm (4.7 in) of rainfall. Which is the driest month in John O Groats? May is the driest month with 60mm (2.4 in) of precipitation. Which is the sunniest month in John O Groats? May is the sunniest month with an average of 192 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.