Have you noticed frequent short bursts of rain recently in the mornings? Are these “Sumatras”?
“Sumatras are line of thunderstorms which usually occur during the Southwest Monsoon season from May to October each year. These squalls develop at night over Sumatra or the Malacca Straits and move east towards Singapore and the west coast of Peninsular Malaysia during the pre-dawn and early morning. They are often characterised by sudden onset of strong gusty surface winds and heavy rain lasting from 1 to 2 hours as they move across the island. Maximum gusts of up to 50 knots have been recorded during the passage of a Sumatra squall.”
– NEA FAQ.