Oregon is entering September under an abrupt change in weather as a succession of unusually strong storm systems descends from the Gulf of Alaska, replacing the state’s prolonged summer dryness with widespread rain, gusty winds, falling temperatures and the possibility of thunderstorms.
The most consequential period is expected Wednesday and Thursday, when a deeper low-pressure system and its associated front cross the Pacific Northwest. Western Oregon will receive the greatest rainfall, but the effects will extend from the coast and Willamette Valley into Southern Oregon, the Cascades and portions of the state east of the mountains.
For a state that has spent much of the summer contending with wildfire, smoke, parched vegetation and exceptionally dry ground, the change will be pronounced. Temperatures in some areas will fall 15 to 20 degrees below seasonal norms while substantial precipitation reaches sections of Oregon that have received little meaningful rainfall for weeks…