A significant haze of wildfire smoke is set to blanket major cities in the Northwest, including Seattle and Portland, as dangerous heat waves continue to grip the region. Spokane is experiencing waves of smoke drifting into Northern California while multiple counties in Oregon are under air quality alerts due to increasing smoke levels. Reports indicate that Portland may rank among the top 10 cities worldwide for the worst air quality, prompted by the advance of wildfire smoke and high temperatures. Residents are urged to prepare for declining air quality as the smoke is expected to linger and possibly worsen in the coming days. Health officials warn that sensitive groups may be adversely affected, and measures are advised to protect homes and health during this challenging period. Escalating wildfire activity in Washington state is further complicating the situation, causing air quality advisories to be issued across various counties.