September in Ellicott City averages a daily high of 26.4°C with nights around 15.3°C. Expect roughly 9.2 wet days totalling 113.3mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Ellicott City is April–May.
Based on BALTIMORE WASHINGTON INTERNATIONAL AIRPORT, MD US (14.4km), 1995–2024. 30 years of September data.