Singapore - Climate

At only 135 km (85 miles) north of the Equator, the weather is usually sunny with no distinct seasons. However, most rainfall occurs during the northeast monsoon (November to January). Showers are usually sudden and heavy but also brief and refreshing, although humidity is uncomfortably high at this time of year. In summer, forest fires in neighboring Sumatra can also cause dense haze.
Spectacular thunder storms can occur throughout the year, normally in the afternoons, so it's wise to carry a umbrella at all times, both as a shade from the sun or cover from the rain.
The temperature averages around:
26C (79F) daytime, 24C (76F) at night in December and January
31C (89F) daytime, 26C (80F) at night for the rest of the year.
The high temperature and humidity, combined with the lack of wind and the fact that temperatures stay high during the night, can take its toll on visitors from colder parts of the world. Bear in mind that spending more than about one hour outdoors can be very exhausting, especially if combined with moderate exercise. Singaporeans themselves shun the heat, and for a good reason. Many live in air-conditioned flats, work in air-conditioned offices, take the air-conditioned metro to air-conditioned shopping malls connected to each other by underground tunnels where they shop, eat, and exercise in air-conditioned fitness clubs. Follow their example if you want to avoid discomfort.