Planning for the weather is a good way to make your trip to Bothell relaxing and enjoyable, especially when you’re splurging. The hottest months are usually August and July, with an average temperature of 17°C, while the coldest months are February and December, with an average of 5°C. The rainiest months in Bothell are November, January, December and October, with each month seeing an average of 184 mm of rainfall.