Question 1

What is the weather like in Tacoma by month?

Accepted Answer

No monthly climate normals are on file for Tacoma.

Question 2

When is air quality worst in Tacoma?

Accepted Answer

September carries the highest modelled PM2.5 of the year at about 17 µg/m³. The WHO 2021 annual guideline is 5 µg/m³. These are model values, not station readings.

Tacoma weather by month