Average Portland area temps fall, sights set on autumn

PORTLAND, Ore. (KOIN) — Average afternoon highs are starting to fall as the peak of the summer season slowly slips away in the Pacific Northwest.

Portland area temperatures are still hot, but the average high has gone from 84 to 83 degrees this week. This is the first decreasing average temperature change Portland has seen this summer season. Typically, Portland's hottest average high daily temperature is 84 degrees from July 24 to August 5. The one-degree average temperature drop on August 6 is the first sign of Portland's cooling temperatures. The new average daytime high for the final day of August is 80 degrees. So that means average temperatures will continue to cool until January 7, 2025. That's when Portland sees its average warming trend increase from 46 degrees to 47 degrees.

Despite the slightly cooler average temperature trend, forecast highs remain much hotter. Afternoon temperatures will return to the mid to upper 90s later this week. That comes as rain-free skies remain and drought likely worsens.

Fall rains and temperatures don't reappear around Portland until September. That's when the average rain accumulation jumps up by nearly an inch. Average temperatures also fall by nearly 10 degrees from the start of the month to the final day of September.