Wettest October in Four Decades with Wet Weather Expected to Continue in the First Half of November 2022

Singapore, 1 November 2022 – Inter-monsoon conditions have prevailed over Singapore in the second half of October 2022 and will likely persist into November 2022. The current wet weather is expected to continue, with thundery showers expected on most days in the first fortnight of November 2022.

2        With the monsoon rain band forecast to remain over the Southeast Asia region, Singapore can expect a continuation of wet days in the coming fortnight. During the period, thundery showers are forecast on most days. In the first week of November 2022, Sumatra squalls developing in the Strait of Malacca may bring widespread thundery showers with occasional gusty winds as they pass Singapore between the pre-dawn hours and morning on some days. In the latter half of the fortnight, afternoon thundery showers can be expected on most days, with the showers extending into the evening on a few days. The total rainfall for the first fortnight of November 2022 is forecast to be above average over most parts of the island.

3        During the fortnight, the daily temperature on most days is forecast to range between 24 degrees Celsius and 33 degrees Celsius. The wetter weather may bring relatively lower temperatures on a few days, with daily minimum temperatures below 23 degrees Celsius and daily maximum temperatures below 32 degrees Celsius.

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 – 31 October 2022)

5        In the second half of October 2022, Singapore and the surrounding region experienced inter-monsoon conditions. The low-level winds that blew predominantly from the southeast or southwest since June 2022 gradually weakened and became mostly light and variable in direction. The monsoon rain band remained close to the equatorial Southeast Asia region, and brought thundery showers over Singapore on most days in the second half of the month.

6        In October 2022, the influence of several tropical storms over the South China Sea and Western Pacific Ocean resulted in large-scale convergence of winds over Singapore and the surrounding vicinity. This led to the development of several Sumatra squalls that brought widespread showers and gusty winds over Singapore between the pre-dawn hours and morning on most days. Thundery showers also fell over the island on several afternoons and nights. The Sumatra squall which brought heavy thundery showers over many parts of Singapore in the morning of 5 October 2022 resulted in a daily total rainfall of 138.1mm recorded at Pasir Panjang. This was the highest daily total rainfall for October 2022.

7        Based on the rainfall averaged across the island-wide stations with long-term records since 1980, October 2022 is the wettest October in four decades, with a monthly total rainfall of 412.0mm. This exceeded the previous highest October rainfall of 389.3mm, which was recorded in October 2011. The Changi climate station experienced a total of 27 rain days in October 2022. This is the highest number of rain days occurring in October at the Changi climate station since the 1980s, and surpasses the previous record of 21 days observed in 1985 and 2003.

8        In October 2022, the daily maximum temperature was below 33 degrees Celsius on most days due to the rainy weather. The wet weather brought several days with cool night time temperatures. There were 23 days with daily minimum temperatures of 24 degrees Celsius or less. The temperature at Jurong Island dropped to 21.9 degrees Celsius during the showers on 12 October 2022. That was the lowest daily minimum temperature for October 2022.

9      Well above-average rainfall was received across the island in October 2022. The highest anomaly of 232 per cent above-average was recorded around the Kent Ridge area. The anomaly was lowest at Paya Lebar at 29 per cent above-average.

 

 

 

 

 

CLIMATE STATION STATISTICS

Long-term Statistics for November
(Climatological reference period: 1991 – 2020)

Average daily maximum temperature: 31.2 °C
Average daily minimum temperature: 24.6 °C
Average monthly temperature: 27.2 °C
Average rainfall: 252.3 mm
Average number of rain days: 19

 

Historical Extremes for November
(Rainfall since 1869 and temperature since 1929)

Highest monthly mean daily maximum temperature: 32.3 °C (2019)
Lowest monthly mean daily minimum temperature: 22.4 °C (1933)
Highest monthly rainfall ever recorded: 521.5 mm (1874)
Lowest monthly rainfall ever recorded: 53.5 mm (1981)