October in Rockville averages a daily high of 20.7°C with nights around 8.8°C. Expect roughly 9.4 wet days totalling 110.7mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Rockville is April–May.
Based on DALECARLIA RESERVOIR, MD US (16.5km), 1995–2024. 28 years of October data.