If you’re hoping to get lost in the rain on your romantic getaway, take a look at these details about year-round temperatures in Ardnamurchan Peninsula: The hottest months are usually August and July, with an average temperature of 13°C, while the coldest months are February and January, with an average of 6°C. The rainiest months in Ardnamurchan Peninsula are October, December, November and January, with each month seeing an average of 218 mm of rainfall.