PORTLAND, Ore. (KOIN) — Late summer heat returns to the Portland area on the final day of summer. This is the warm before Oregon and Washington sees its next first major storm of the season.
An atmospheric river is taking shape over the Pacific Ocean. Those impacts will be felt from Washington to Northern California, but not before warmer temperatures return to the region. Dry, sunny, and hazy conditions will send afternoon highs close to 80°F.

The haze is due to a low pressure system exiting the region and pulling wildfire smoke back into western Oregon and Washington. That will clear as the atmospheric river brings an onshore flow and heavy rain washes out the skies next week.


Clouds will slowly start to increase during the evening clouds. Those are the prefrontal clouds to the wet weather that will remain over the Pacific Northwest through the weekend and into next week.

The wet weather trend will also drop temperatures below normal for the final week of September.