Singapore Experiencing Southwest Monsoon Conditions

Expect dry and warm conditions in first half of June 2017

Singapore, 1 June 2017 –   Southwest Monsoon conditions characterised by low level winds that blow predominantly from the southeast or southwest set in over Singapore in the second half of May 2017. The Southwest Monsoon season which extends from June to September is generally drier compared to other times of the year.

2         In the first fortnight of June 2017, the prevailing winds are forecast to blow from the southeast or southwest. During the period, Singapore can expect dry weather conditions on most days, and localised short-duration thundery showers due to strong solar heating of land areas are expected in the late morning and early afternoon on three or five days. In the latter half of the fortnight, thundery showers with gusty winds due to Sumatra squalls can be expected on one or two days between the predawn hours and early morning. Rainfall for the first fortnight of June 2017 is likely to be below-normal.

3         In the first half of June 2017, some warm days can be expected. On these days, the daily maximum temperature could reach a high of around 35°C, and the daily minimum temperature is expected to be around 26°C. On other days, the daily temperature is forecast to range between 25°C and 34°C.

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

Review: 1 – 31 May 2017

5         In the second half of May 2017, the prevailing light and variable winds gradually strengthened to blow from the southeast or southwest as the region transitioned from the inter-monsoon period to the Southwest Monsoon season.

6         There were some warm days in May 2017. The highest daily maximum temperature was 35.0°C recorded at Choa Chu Kang on 31 May 2017[1]. On days when it rained, the lowest daily minimum temperature recorded ranged between 22.2°C and 22.9°C.  At the Changi climate station, the mean monthly temperature recorded in May 2017 was 28.4°C, approximately 0.1°C warmer than the long-term mean temperature for May.

7         In May 2017, Singapore experienced thundery showers in the late morning and early afternoon on most days due to convergence of winds over Singapore and the surrounding vicinity. On a few days of the month, the occurrence of Sumatra squalls brought widespread thundery showers to Singapore in the predawn and early morning. The thundery showers were heaviest on 31 May 2017 where the highest daily rainfall total recorded was 96.2mm around the Simei area.

8         Most parts of Singapore received above normal rainfall in May 2017. The highest rainfall of 303.7mm (58% above average) was recorded around the Paya Lebar area. Rainfall was lowest around the Kranji area where 172.2mm (19% below average) was recorded.

[1] Figure for highest daily maximum temperature for May was corrected on 16 Jun 2017

FortnightRain_Anomaly_201705b (1)

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 monthly mean daily minimum temperature 24.4 °C (1989)
Highest monthly rainfall 265.8 mm (1996)
Lowest monthly rainfall 21.8 mm (2009)