Guilin has a monsoon-influenced humid subtropical climate (Köppen Cfa), with short, mild winters, and long, hot, humid summers. Winter begins dry but becomes progressively wetter and cloudier. Spring is generally overcast and often rainy, while summer continues to be rainy though is the sunniest time of year. Autumn is sunny and dry. The monthly 24-hour average temperature ranges from 7.9 °C (46.2 °F) in January to 28.0 °C (82.4 °F) in July, and the annual mean is 18.84 °C (65.9 °F). The annual rainfall is just above 1,900 mm (75 in), and is delivered in bulk (~50%) from April to June, when the plum rains occur and often create the risk of flooding. With monthly percent possible sunshine ranging from 14% in March to 53% in September, the city receives 1,487 hours of bright sunshine annually.