Singapore, 1 November 2021 – Inter-monsoon conditions have been prevailing over Singapore in the second half of October 2021 and are expected to persist into November 2021. In the first half of November 2021, the low-level winds are forecast to be light and variable in direction; and may temporarily blow from the northwest or west on several days.
2 With the monsoon rain band forecast to remain over the equatorial Southeast Asia region, Singapore can expect more wet days in the coming fortnight. During the period, afternoon thundery showers are forecast on most days, with the showers extending into the evening on a few of these days. On a few days, widespread moderate to heavy thundery showers are expected due to large-scale convergence of winds over Singapore and the surrounding region. In addition, the passage of Sumatra squalls could bring widespread thundery showers and gusty winds on a few mornings. The total rainfall for the first half of November 2021 is forecast to be above average over most parts of the island.
3 The daily temperature on most days in the first two weeks of November 2021 is forecast to range between 24°C and 33°C. Although showers are expected on most days of the fortnight, the daily maximum temperature could still reach a high of around 34°C on a few days. In addition, the wetter weather in the coming fortnight may bring relatively lower temperatures to the island on a few days, with daily maximum temperatures below 32.0°C and daily minimum temperatures below 23°C.
REVIEW (1 – 31 October 2021)
5 Singapore and the surrounding region experienced inter-monsoon conditions in the second half of October 2021. The low-level winds that blew predominantly from the southeast or southwest since June 2021 gradually weakened and became mostly light and variable in direction towards the second fortnight of October 2021. 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 During the month, short-duration thundery showers fell over a few parts of Singapore in the late morning and afternoon on most days. Compared to the first half of October 2021, Singapore experienced more rain days in the second half of the month. On a few days, large-scale convergence of winds over Singapore and the surrounding vicinity brought widespread moderate to heavy thundery showers. The highest daily total rainfall for October 2021 occurred on 31 October 2021, when 84.8 mm of rain fell around the Sentosa area in the afternoon.
7 October 2021 was a warm month with daily maximum temperatures exceeded 34°C on 17 days. The highest daily maximum temperature of 35.5°C was recorded at Marina Barrage on 12 October 2021. At the Changi climate station, the mean monthly temperature recorded in October 2021 was 28.5°C, which is 0.6°C higher than the long-term mean of 27.9°C for October.
8 Most parts of the island received slightly below-average rainfall in October 2021. The highest anomaly of 40% below average was recorded at Bishan. The eastern part of Singapore was slightly wetter where 19% above average rainfall was recorded around Simei.
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)|