Singapore is experiencing a prolonged dry spell due to something known as the Indian Ocean Dipole (IOD) - a complex climate phenomenon whose positive phase causes similar climate variations as the better known El Nino.
The Meteorological Service Singapore (MSS) had announced earlier in August that though El Nino had not been detected, the positive phase of IOD will cause changes in atmospheric pressure and sea surface temperature across the Indian Ocean. The hotter and drier weather over South-east Asia is a result of this positive phase of IOD and is likely to persist for months ahead, said an MSS advisory.
A high of 34.5 degrees Celsius was recorded at Marina Barrage on August 13. A spokesperson for national water agency Public Utilities Board (PUB) said there has been a slight drop in the water level at Bedok Reservoir due to the warm weather.
During dry months, PUB will top up Singapore's reservoirs with Newater, or reclaimed water, to keep water reserves at a healthy level, as is common during the dry weather period, PUB announced. "(This) will be further treated at the waterworks before supplying it to the population."
The main rainy seasons in Singapore are the Northeast Monsoon that occur from December to early March, and the Southwest Monsoon from June to September. It is the latter season that has seen an extended dry spell this year.