temperature in hillsboro or
The highest monthly average temperature in Hillsboro for July is 68 degrees. The lowest monthly average temperature in Hillsboro for December is 37 degrees. The most monthly precipitation in Hillsboro occurs in November with 6.5 inches. The air quality index in Hillsboro is 23% better than the national average. The pollution index in Hillsboro is 197% worse than the national average.