Short-Duration Thundery Showers in Second Half of June 2016

Near average rainfall expected for June

Advisory

Singapore, 16 June 2016 – The Southwest Monsoon conditions which set in during the first half of June 2016 are expected to persist into the second fortnight of June 2016. During this period, the low level winds are forecast to blow mainly from the southeast or southwest.

2          In the second half of June 2016, short-duration thundery showers can be expected mostly in the late morning and afternoon on five to seven days, due to strong day time convective heating and convergence of winds around Singapore and the surrounding vicinity. In addition, widespread thundery showers with occasional gusty winds due to Sumatra squalls, are likely in the predawn hours and morning on one to two days. The rainfall for June 2016 is likely to be near average.

3          During the outlook period, the daily maximum temperatures are forecast to range between 32°C and 33°C, reaching around 34°C on a few days. This is within the typical daily maximum temperature range for June.

REVIEW (1 – 15 June 2016)

4          Southwest Monsoon conditions prevailed in the region in the first fortnight of June 2016 with the low level winds blowing from the southeast or southwest.

5          During the review period, the highest daily maximum temperature recorded was 34.6°C over the north-eastern part of Singapore around the Seletar area. On days when there was rainfall, the lowest recorded daily minimum temperature fell to between 22°C and 23°C.  As of 15 June 2016, the mean monthly temperature recorded at the Changi climate station was 28.6°C, slightly warmer than the June long-term mean of 28.3°C.

6          Thundery showers in the late morning and early afternoon were experienced over Singapore on most days in the first two weeks of June 2016.  The showers were due to strong heating of land areas coupled with convergence of winds in the surrounding vicinity. The heaviest rain fell on 2 June 2016 and brought a total of 86.6mm of rainfall to the Seletar area.

7          Most parts of Singapore received above average rainfall in the first half of June 2016. The highest rainfall of 222mm (187% above average) was recorded around Seletar. Rainfall was lowest around Sentosa where 46.8mm (31% below average) was recorded.

FortnightRain_Anomaly_201606b

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

Mean daily maximum temperature 32.0 °C
Mean daily minimum temperature 25.4 °C
Mean monthly temperature 28.3 °C
Mean rainfall for the month 130.7 mm
Mean number of rain days 12
Highest monthly mean daily maximum temperature 33.2 °C (1997)
Lowest monthlymean daily minimum temperature 24.4 °C (1989)
Highest monthly rainfall 265.8 mm (1996)
Lowest monthly rainfall 21.8 mm (2009)