Hillsboro, OR Air Quality

About Hillsboro weather

Hillsboro is in Washington County, Oregon, United States at 45.52°, -122.99°. Right now it’s 51° and clear; today’s high is 73° with a 0% chance of rain.

Oregon's climate is dramatically divided by the Cascade Range, creating a lush, rainy western region and an arid eastern high desert. The Willamette Valley, where most of the state's population lives, has a mild maritime climate with cool, wet winters and warm, dry summers. Portland receives about 37 inches of rain annually, most of it between October and May, with summers that are among the driest of any major U.S. city.