The Infectious risk has risen noticeably over the past 12 weeks, ending the period at its highest level..
Allergy risk activity has been climbing over the past 12 weeks in Snohomish, Washington.
Pollution risk activity has been climbing over the past 12 weeks in Snohomish, Washington.
Weather risk activity has been climbing over the past 12 weeks in Snohomish, Washington.
Last updated: August 24, 2026
Data refreshed weekly