May was slightly drier than usual with only 249 millimetres of rain, about 79% below the normal 316.7 millimetres.

However, the first Red Rainstorm and Landslip Warnings of the year were issued on May 5.

The accumulated rainfall since the beginning of the year was 408.9 millimetres, about two-thirds the normal figure of 616.5 millimetres for the same period.

The rain was heaviest in the small hours of May 5 when a trough of low pressure developed along the South China coast.

Some 89 reports of flooding, mostly in the northern New Territories, were received. A senior police inspector died in a rescue mission in a flooding incident at Lin Ma Hang.

The weather improved on May 6 when the trough dissipated.

Troughs caused more storms and showers on May 18 and 25.

For details on weather warnings and signals in May, please click here. Monthly meteorological figures are available here.