Overview

• The National Weather Service on Saturday extended extreme heat warnings from Sunday noon through Tuesday morning for the Willamette Valley and Portland metro area, forecasting highs of 97°F to 105°F.
• Heat watches and advisories now cover much of Oregon, including the Curry County coast, central valleys and mountain foothills, warning of daytime temperatures up to 110°F and overnight lows in the 60s.
• Northern California has entered its first heat wave since mid-July, with a four-day stretch of triple-digit highs expected from Friday through Monday under the eastern Pacific ridge.
• Persistent high pressure is limiting nighttime relief and elevating risks of heat-related illnesses, prompting officials to urge residents to stay hydrated, seek cool shelter and check on vulnerable neighbors.
• Forecast models predict temperatures will retreat toward seasonal norms by midweek as the high-pressure ridge weakens and a cooling trough moves inland.