As for a reference in the equatorial regions and referring to a local Indonesian saying that any months ending in ‘er’ i.e.: Septemb-er, Octob-er, Novemb-er, Decemb-er, is referring to the Indonesian word for bucket = Amb- ‘er’; so in the village you get your buckets ready, these months are the rainy ones!
In general, these tropical rains brought about by the North-West Monsoon are a pleasant change from the dry season, rains are usually in the evening early morning or late afternoon, and these NW monsoons bring the perfect offshore winds for the Point in Sorake.
On the equator, the months of January February March are hot and humid, evaporation of the tropical rain soaked into the soil makes it humid and hot, these times you can literally see the bamboo grow!
March onwards the weather becomes dryer, with rain usually during the evening. Winds can be calm and steady, dictated by the intensity of the prevailing La-Nina to El-Nino and Indian Ocean Dipole of water temperature in the mass of the Indian Ocean. Nias can in times be effected by the South-East Trades moving up onto the equator, (influenced by strong El-Nino) Or the familiar equatorial glassy calms with mornings of steady land drafts breeze from the summer weather patterns of the Northern Hemisphere.