Beihai has a monsoon-influenced humid subtropical climate with mild to warm winters and long, hot (but not especially) summers, and very humid conditions year-round. The monthly 24-hour average temperature ranges from 14.6 °C (58.3 °F) in January to 29.0 °C (84.2 °F) in July, while extremes have ranged from 2.6 to 37.1 °C (37 to 99 °F). Rain is both the heaviest and most frequent from June to September, when 70% of the annual rainfall also occurs. This is in contrast to the autumn and winter months, where only 20 to 40 millimetres (0.79 to 1.57 in) of rain falls per month. The area receives about 2,000 hours of sunshine annually.