If you’re hoping to get lost in the rain on your romantic getaway, check out these details about year-round temperatures in Rab: The hottest months are usually August and July with an average temp of 63°F, while the coldest months are January and February with an average of 35°F. The rainiest months in Rab are November, September, May, and October, with each month seeing an average of 7 inches of rainfall.