If you’re hoping to get lost in the rain on your romantic getaway, check out these details about year-round temperatures in Sitiawan: The hottest months are usually May and June with an average temp of 82°F, while the coldest months are January and February with an average of 80°F. The rainiest months in Sitiawan are November, December, October, and March, with each month seeing an average of 12 inches of rainfall.