Historical weather data, all-time temperature records, and monthly climate averages for Bothell, WA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 4th in Bothell typically lands in that classic Pacific Northwest in-between zone — average highs of 55° with rain falling just over half the time. This date's range is surprisingly wide though, from a frosty 31° back in 2009 to a shirt-sleeve 67° just this year in 2025.
Bothell's weather has real range — from a scorching 107° during the historic Pacific Northwest heat dome of June 2021 to a bone-chilling 10° in December 1990. That same brutal December dropped 8 inches of snow in a single day, a reminder that this corner of Washington can occasionally punch well outside its mild reputation.
Summer is the clear sweet spot, with highs peaking around 77-79° in late July through early August and very little rain to speak of. If you're trying to avoid the wet season, steer clear of November through January — late November averages over 1.5 inches of rain in a single week. Spring and fall offer mild temps in the 50s and 60s but come with a coin-flip chance of showers on any given day.