The haze is expected to be caused by wildfires burning in the Pacific Northwest, particularly in Oregon. The smoke will likely be transported by winds from the west and southwest, bringing it to Portland. The haze is expected to impact air quality, potentially leading to unhealthy levels of particulate matter in the air. This could pose a health risk to vulnerable populations, such as children, the elderly, and those with respiratory conditions. The National Weather Service has issued a hazardous weather outlook for Thursday, warning of the potential for unhealthy air quality. The outlook also includes a high risk of wildfires in the Pacific Northwest.

This creates a situation where even a small spark can ignite a large and destructive wildfire.

The city will experience a slight increase in humidity on Saturday, but it will remain relatively low. Humidity will continue to increase on Sunday, reaching a moderate level. The city will see a slight increase in wind speeds on Saturday, reaching up to 10 miles per hour. Wind speeds will remain relatively low on Sunday. The city will experience a slight increase in precipitation on Saturday, with a chance of showers. The chance of showers will decrease on Sunday.