Monthly Archives: April 2019

Inter-monsoon conditions to persist in the next fortnight. Expect mostly short-duration afternoon thundery showers & 3-5 mornings of widespread showers with gusty winds. Expect warm conditions with daily max temperatures of 34°C or more.

Singapore, 30 April 2019 – Inter-monsoon conditions have been prevailing since late March 2019 and are forecast to continue into May 2019. During this period, more occurrences of thundery showers can be expected over Singapore and the surrounding region, and the low level winds are forecast to be light and variable in direction. Climatologically, May has one of the highest number of lightning days in the year; May is also one of the warmest months of the year.

2         In the first half of May 2019, strong solar heating of land areas during the day are expected to bring short-duration moderate to heavy thundery showers in the afternoon on four to six days. On a few of these days, the thundery showers could extend into the evening. In addition, on three or five days, particularly in the second week of the fortnight, Sumatra squalls could bring widespread thundery showers with gusty winds in the predawn and morning. Overall, the rainfall for the first half of May 2019 is likely to be near-normal over most parts of Singapore.

3         Warm conditions to continue into the fortnight. On most days, the daily temperature is forecast to range between 25°C and 34°C. On a few days, the heat can be sweltering as the daily maximum temperature could reach around the high end of the 35°C range when there is little or no rainfall.

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

REVIEW (1 – 29 April 2019)

5         Inter-monsoon conditions with low level winds that were light and variable in direction prevailed over Singapore and the surrounding region in April 2019. During the month, the presence of the monsoon rain band over the equatorial region contributed to more thundery showers over Singapore and the surrounding region, compared to March 2019.

6         In April 2019, thundery showers fell over the island in the afternoon on most days, and extended into the evening on a few of these days. This was due to strong solar heating of land areas and light winds over Singapore and the surrounding vicinity. The eastward passage of Sumatra squalls on a few days brought widespread moderate to heavy thundery showers and gusty winds to Singapore in the predawn and early morning. In particular, on 26 April 2019, the Sumatra squall over Singapore between the late morning and afternoon recorded a daily total rainfall of 118.7mm at Changi. This was the highest rainfall recorded in a day in April 2019.

7         April 2019 was also particularly warm. More than half the month had daily maximum temperatures exceeding 34°C. The highest daily maximum temperature of 36.4°C was recorded at Paya Lebar on 17 April 2019. This is close to the highest ever recorded daily maximum temperature of 37°C (1983) for April since temperature records started in 1929.

8         More than two-thirds of Singapore received slightly below-normal rainfall in April 2019. Rainfall was lowest at Seletar where 143.2 mm (36% below average) of rain was recorded. The highest rainfall of 299.8 mm (53% above average) was recorded over the south-eastern part of the island at Tanjong Katong.

CLIMATE STATION STATISTICS

Long-term Statistics for May
(Climatological reference period: 1981 – 2010)

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

Expect 6-8 days of short-duration thundery showers between late morning and afternoon and Sumatra squalls on 1-2 mornings. Warm conditions expected. Daily max temp could rise around 35°C on a few days.

Singapore, 16 April 2019 – The prevailing inter-monsoon conditions in Singapore and the surrounding region are expected to persist through May 2019.

2         During the inter-monsoon period, the low level winds are generally light and variable in direction. There is also strong solar heating of land areas, and coupled with convergence of winds over Singapore and the surrounding vicinity, short-duration thundery showers accompanied by high lightning activity typically occur in the afternoons.

3         In the second half of April 2019, moderate to heavy short-duration thundery showers are expected between the late morning and afternoon on six to eight days. In addition, on one or two days, the passage of Sumatra squalls could bring widespread thundery showers and gusty winds in the morning. The rainfall for April 2019 is forecast to be near-normal.

4         Although thundery showers are expected on most days for the rest of April 2019, it is also expected to be warm. The daily temperature on most days is forecast to range between 25°C and 34°C. On a few afternoons, the daily maximum temperature could reach a high of 35°C.

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

REVIEW (1 – 15 April 2019)

6         During the first half of April 2019, inter-monsoon conditions prevailed over Singapore and the surrounding region. The low level winds were generally light and variable in direction, and the monsoon rain band was located over the equatorial region. This brought wet conditions over Singapore and the surrounding region, a welcome relief from the prolonged drier and hotter than usual conditions experienced on most days since late January 2019.

7         In the first half of April 2019, light winds and strong solar heating of land areas led to the development of thunderstorm clouds on most days. Intense short-duration thundery showers fell over many areas in the afternoon on some days. The thundery showers over the Tai Seng area in the late afternoon of 10 April 2019 recorded 71.4mm of rain. This was the highest total rainfall in a day for the first fortnight of April 2019.

8         On a few days in early April 2019, the winds blew from the southwest or west, and Sumatra squalls moved over Singapore in the predawn hours and early morning. This brought widespread thundery showers and gusty winds over many areas of the island. The wind gust of 75.6km/h at Pasir Panjang during the passage of a squall on 3 April 2019 was the highest recorded wind gust for April 2019 so far.

9         Despite the wet weather on most days in the first fortnight April 2019, there were several days that were very warm with the daily maximum temperature rising to above 35°C. During the period, the highest daily maximum temperature recorded was 36.0°C at Admiralty on 7 April 2019.  On most days, the daily temperature ranged between 24°C and 34°C.

10         More than two-thirds of the island received below-normal rainfall in the first fortnight of April 2019. The highest rainfall of 168.4 mm (67% above average) was recorded at Tanjong Katong. Rainfall was lowest at Choa Chu Kang where 52.6 mm (59% below average) was recorded.

CLIMATE STATION STATISTICS

Long-term Statistics for April
(Climatological reference period: 1981 – 2010)

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