Singapore, 2 October 2023 – The prevailing Southwest Monsoon conditions are likely to persist over Singapore and the surrounding region, and the low-level winds are expected to blow from the southeast or southwest on most days. On a few days, the winds may temporarily weaken to become light and variable in direction.
2 In the coming fortnight, localised thundery showers are expected between the late morning and afternoon over parts of the island on most days due to the daytime heating of land areas. On one or two days, regional convergence of winds may bring widespread moderate to heavy thundery showers over Singapore in the afternoon. Overall, the rainfall for the first half of October 2023 is likely to be below average over most parts of Singapore.
3 The daily maximum temperatures are expected to range between 33 degrees Celsius and 34 degrees Celsius on most days. Although showers are expected on most days in the coming fortnight, the daily maximum temperature could still reach a high of slightly above 34 degrees Celsius on one or two days.
4 The showers over Singapore are expected to be mostly of short duration. With dry weather expected to continue in some parts of the surrounding region, Singapore may experience hazy conditions if the prevailing winds turn southwesterly and forest fires in Sumatra continue to persist. NEA will continue to closely monitor the situation and provide further updates if the situation changes. Should the 24-hour PSI be anticipated to enter the Unhealthy range, NEA will provide daily haze advisories.
5 For updates of the daily weather forecast and PSI readings, please visit the MSS website (www.weather.gov.sg), NEA website (www.nea.gov.sg), or download the myENV app.
REVIEW (1 – 30 September 2023)
6 Southwest Monsoon conditions prevailed over Singapore and the surrounding region in September 2023, with low-level winds blowing mostly from the southeast or southwest.
7 Localised short-duration thundery showers fell over parts of the island in the late morning and afternoon on several days. On 6 September 2023, large-scale convergence of winds over Singapore and the surrounding region led to the development of widespread moderate to heavy thundery showers over many parts of the island in afternoon. The daily total rainfall of 157.5 mm recorded at Lower Peirce Reservoir that day was the highest rainfall recorded for September 2023. On 24 September 2023, a Sumatra squall brought moderate to heavy thundery showers over many parts of Singapore in the morning. There were also several days where the weather was generally fair and occasionally windy.
8 The daily maximum temperatures in September 2023 were above 32 degrees Celsius on all days except 24 September 2023. The highest daily maximum temperature of 34.9 degrees Celsius was recorded at Sentosa on 19 September 2023. On several nights, the daily minimum temperatures over the eastern, southern and western coastal areas of the island were above 28 degrees Celsius.
9 Most parts of Singapore recorded above average rainfall in September 2023. Lower Peirce Reservoir recorded rainfall of 85 per cent above average, and Tengah recorded rainfall of 45 per cent below average.
CLIMATE STATION STATISTICS
Long-term Statistics for October
(Climatological reference period: 1991 – 2020)
| Average daily maximum temperature: | 31.8 °C |
| Average daily minimum temperature: | 25.0 °C |
| Average monthly temperature: | 27.9 °C |
| Average rainfall: | 168.3 mm |
| Average number of rain days: | 15 |
Historical Extremes for October
(Rainfall since 1869 and temperature since 1929)
| Highest monthly mean daily maximum temperature: | 33.0°C (2002) |
| Lowest monthly mean daily minimum temperature: | 22.8 °C (1964) |
| Highest monthly rainfall ever recorded: | 497.1 mm (1947) |
| Lowest monthly rainfall ever recorded: | 10.8 mm (2002) |