December in Dallas averages a daily high of 15.3°C with nights around 4.5°C. Expect roughly 6.5 wet days totalling 73mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Dallas is March–April.
Based on DALLAS FAA AIRPORT, TX US (6.7km), 1995–2024. 30 years of December data.