December in Grays averages a daily high of 9°C with nights around 3.1°C. Expect roughly 14.5 wet days totalling 58.4mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Grays is May–September.
Based on HEATHROW, UK (8.6km), 1995–2024. 30 years of December data.