December in Ellicott City averages a daily high of 8.6°C with nights around -1°C. Expect roughly 10.3 wet days totalling 94.8mm. Demanding conditions — pack for it and plan indoor options.
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 December data.