Like most equatorial regions, Kuala Lumpur weather has little fluctuation in temperature, remaining sultry and warm throughout the seasons, with daytime temperatures averaging 29˚C to 35˚C and night-time readings falling between 26˚C and 29˚C. A typical day is characterized by intensely hot sunshine during the morning hours and into the afternoon; with late afternoon and evening bringing occasional rain showers and thunderstorms. Increasingly high temperatures have been partially attributed to global warming and deforestation.
The amount of humidity and rainfall varies substantially during the year, with the northeast monsoon season from October through March bringing considerably more precipitation. Typical rainfall is a minimum of 2,600 mm annually. Though most rain falls in brief showers, during monsoon season heavy deluges and downpours are common, and flooding frequently occurs, particularly in the city centre and other downstream areas. Average humidity is around 66.67. Driest months are generally May through July.
With the protection of the Titiwangsa Mountains to the east and the island of Sumatra to the west, Kuala Lumpur is blessed with cooler temperatures than much of Malaysia, as well as relatively milder monsoon winds coming in from either direction. Visitors may notice a slight haze over the region from time to time, caused by dust particles carried over from forest fires in Sumatra; this, combined with open burning and motor vehicle emissions, is a major cause of pollution in Kuala Lumpur.