Singapore, 30 August 2023 – The prevailing Southwest Monsoon conditions are expected to persist over Singapore and the surrounding region in the first fortnight of September 2023, with low-level winds blowing from the southeast or southwest.
2 The monsoon rain band is forecast to be mainly confined over the northern Southeast Asia region in the first half of September 2023, bringing less rainfall over Singapore. In the first week of September 2023, the presence of a dry air mass over Singapore and the surrounding region is expected to bring a few fair and windy days. Short-duration thundery showers are expected between the late morning and afternoon over parts of the island on some days, particularly in the second week of the month. The passage of Sumatra squalls may bring widespread thundery showers and gusty winds to Singapore on one to two mornings. Overall, the rainfall for the first fortnight of September 2023 is likely to be below average over most parts of Singapore.
3 The first fortnight of September 2023 is expected to be generally warm, with daily maximum temperatures ranging between 33 and 34 degrees Celsius on most days. Several nights may be warm, when the prevailing winds blow from the southeast or south bringing warm and moist air from the sea. On these nights, the temperatures may stay above 28 degrees Celsius, particularly over the eastern and southern coastal areas of the island.
4 For updates of the daily weather forecast, please visit the MSS website (www.weather.gov.sg), NEA website (www.nea.gov.sg), or download the myENV app.
REVIEW (1 – 29 Aug 2023)
5 Southwest Monsoon conditions prevailed over Singapore and the surrounding region in August 2023, with low-level winds blowing mostly from the southeast or southwest.
6 In August 2023, localised short-duration thundery showers fell over parts of the island in the late morning and afternoon on several days. Sumatra squalls also brought widespread thundery showers and gusty winds over Singapore on a few mornings. On 13 August 2023, heavy localised thundery showers fell over eastern Singapore in the early afternoon. The daily total rainfall of 84.4 mm recorded at Simei that day was the highest rainfall recorded for August 2023.
7 It was generally warm in August 2023. The daily maximum temperature in August 2023 was above 33 degrees Celsius on most days. The highest daily maximum temperature of 34.4 degrees Celsius was recorded at Admiralty on 6 August 2023. There were also several warm nights, particularly over the southern and eastern parts of the island where the minimum night-time temperatures remained above 28 degrees Celsius.
8 Most parts of Singapore recorded below average rainfall in August 2023. Jurong recorded rainfall of 21 per cent above average, and Queenstown recorded rainfall of 61 per cent below average.
CLIMATE STATION STATISTICS
Long-term Statistics for September
(Climatological reference period: 1991 – 2020)
| Average daily maximum temperature: | 31.6 °C |
| Average daily minimum temperature: | 25.2 °C |
| Average monthly temperature: | 28.0 °C |
| Average rainfall: | 124.9 mm |
| Average number of rain days: | 13 |
Historical Extremes for September
(Rainfall since 1869 and temperature since 1929)
| Highest monthly mean daily maximum temperature: | 33.0 °C (2019) |
| Lowest monthly mean daily minimum temperature: | 22.4 °C (1930) |
| Highest monthly rainfall ever recorded: | 440.4 mm (1988) |
| Lowest monthly rainfall ever recorded: | 22.8 mm (2019) |