If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Forks: The hottest months are usually August and July, with an average temperature of 15°C, while the coldest months are February and December, with an average of 5°C. The rainiest months in Forks are November, December, January and March, with each month seeing an average of 284 mm of rainfall.