Taking the local weather in Lynnwood into account is an important factor for planning your visit, especially if you plan to spend your trip by the pool. 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 Lynnwood are November, January, December and October, with each month seeing an average of 183 mm of rainfall.