January in Port Arthur averages a daily high of 17.6°C with nights around 6.6°C. Expect roughly 9.1 wet days totalling 116.2mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Port Arthur is February–April.
Based on PORT ARTHUR SE TX REGIONAL AIRPORT, TX US (11km), 1995–2024. 30 years of January data.