January in Mustamäe averages a daily high of -1°C with nights around -5.7°C. Expect roughly 18.3 wet days totalling 56.4mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Mustamäe is June–August.
Based on TALLINN, EN (4.5km), 1995–2024. 30 years of January data.