The Infectious risk has shown a gradual increase over the past 12 weeks, ending the period at its highest level..
Allergy risk activity has been climbing over the past 12 weeks in Union, South Dakota.
No Pollution activity has been reported over the past 12 weeks in Union, South Dakota.
Weather risk activity has been easing over the past 12 weeks in Union, South Dakota.
Last updated: August 24, 2026
Data refreshed weekly