Singapore, 1 September 2025 – Southwest Monsoon conditions are prevailing and expected to persist over Singapore and the surrounding region in the coming fortnight with winds blowing mainly from the southeast or southwest.
2 In the first fortnight of September of 2025, Sumatra squalls may bring widespread thundery showers and gusty winds in the pre-dawn and morning on several days. In addition, moderate to heavy thundery showers are expected over parts of the island in the late morning and afternoon on some days. The total rainfall for the first fortnight of September 2025 is forecast to be above average over most parts of the island.
3 The daily maximum temperatures are likely to range between 32 degrees Celsius and 34 degrees Celsius on most days.
4 For updates of the daily weather forecast, please visit the MSS website (https://www.weather.gov.sg), NEA website (www.nea.gov.sg), or download the myENV app.
REVIEW OF THE PAST TWO WEEKS (15 – 31 AUGUST 2025)
5 Southwest Monsoon conditions prevailed over Singapore and the surrounding region in the second fortnight of August 2025, with winds blowing mostly from the southeast or southwest.
6 In the second fortnight of August 2025, localised short-duration thundery showers fell over parts of the island on several days. Sumatra squalls also brought thundery showers and gusty winds over Singapore in the pre-dawn and morning on a few days. On 24 August 2025, the passage of a Sumatra squall brought widespread thundery showers and gusty winds over Singapore in the early morning. The daily total rainfall of 104.2 mm recorded at Ulu Pandan that day was the highest rainfall recorded for the second fortnight of August 2025.
7 The daily maximum temperatures in the second fortnight of August 2025 were between 32 degrees Celsius and 34 degrees Celsius on most days. The highest daily maximum temperature of 34.7 degree Celsius was recorded at Ang Mo Kio on 22 August 2025.
8 About half of Singapore recorded above average rainfall in the second fortnight of above 2025. The area around Clementi registered rainfall of 128 per cent above average, and the area around Changi registered rainfall of 40 per cent below average.
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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) |