Expect More Thundery Showers For The Rest of December 2018

Expect 6-8 days of afternoon thundery showers in the next fortnight. A monsoon surge towards last week of the fortnight likely to bring 1-2 days of more intense thunderstorm activities and occasionally windy conditions. The daily temperatures between 24°C and 33°C on most days.

Singapore, 14 December 2018 –  The prevailing Northeast Monsoon in the region is expected to persist in the next few months, with the low level winds blowing mostly from the northeast or northwest.

2          In the next fortnight, Singapore can expect short-duration thundery showers in the afternoon and evening on six to eight days.  In addition, towards the last week of December 2018, a surge of monsoon winds over the South China Sea is likely to bring converging winds over the region and more intense thunderstorm activities over Singapore on one to two days, accompanied by occasionally windy conditions.   On another one or two days of the fortnight, the prevailing winds are forecast to temporarily blow from the west, bringing thundery showers in the morning.  The rainfall for December 2018 is expected to be near normal.

3          The daily temperatures in the second fortnight of December 2018 are expected to range between 24°C and 33°C on most days. The daily maximum temperature may reach a high of 34°C on a few days, with the minimum temperature dropping to a low of 23°C on days with intense rainfall.

4          For updates of the daily weather forecast, please visit our MSS website (www.weather.gov.sg), NEA website (www.nea.gov.sg), or download the myENV app, or the MSS’ Weather@SG app.

REVIEW (1 – 13 December 2018)

5          Following the onset of the Northeast Monsoon in late November 2018, Singapore and the surrounding region experienced wet weather conditions in the first fortnight of December 2018 as monsoon rain band developed close to the equatorial South China Sea.  Thundery showers fell over many parts of the island in the afternoon on most days during the period. The highest daily total rainfall of 73.4 mm was recorded on 5 December 2018 over the western parts of Singapore near Lim Chu Kang in the late afternoon.

6          Towards the end of the fortnight, a large-scale convergence of northeasterly winds triggered by a moderate monsoon surge over the South China Sea led to the development of intense thundery showers in the afternoon on 11 December 2018.The highest daily total rainfall was recorded at Pulau Ubin  (73.2 mm) and Thomson Road (72.6 mm) on 11 and 12 December 2018 respectively. Floods were reported over several places near Dunearn Road and Eng Neo Road following the heavy downpour on 12 December 2018.

7          During the fortnight, Singapore’s daily maximum temperature ranged between 32.0°C and 33.7°C on most days.  The highest daily maximum temperature of 34.6°C was recorded on 9 December 2018 in the Marina Bay area. The daily minimum temperature ranged between 23.0°C and 24.5°C

8          More than two thirds of the island received above normal rainfall in the first fortnight of December 2018. The highest rainfall of 262.6 mm was recorded in the Jurong Pier area while Changi recorded the lowest rainfall of 52 mm.



CLIMATE STATION STATISTICS FOR DECEMBER (Climatological reference period: 1981 – 2010)

Mean daily maximum temperature 30.2 °C
Mean daily minimum temperature 24.0 °C
Mean monthly temperature 26.4 °C
Mean rainfall for the month 318.6 mm
Mean number of rain days 18
Highest monthly mean daily maximum temperature 31.3 °C (1997, 2002)
Lowest monthly mean daily minimum temperature 23.0 °C (1981,1983)
Highest monthly rainfall 765.9 mm (2006)
Lowest monthly rainfall 62.9 mm (1988)