Singapore is two degrees north of the equator and has a tropical climate, with high temperatures moderated by the influence of the sea. Average daily temperature and humidity are high, with a mean maximum of 31°C and a relative humidity of 70 to 80 percent in the afternoon. Rain falls throughout the year, but is heaviest during the early northeast monsoon from November through January. The driest month is July in the middle of the southeast monsoon. The intermonsoon months of April-May and October are marked by thunderstorms and violent line squalls locally known as Sumatras. The average annual rainfall is 237 centimeters, and much of the rain falls in sudden showers.

Data as of 1989