Monthly Summary Data October 2021

October 2021 was dominated by the monsoon trough which lay across upper Thailand during the beginning and the middle of the month and it occasionally moved southwards to lie over the upper southern and eastern parts coupled with the active southwest monsoon prevailed over the Andaman Sea, Southern part and the Gulf of Thailand during the same period. Moreover there were 2 tropical cyclones having some effects of rainfall on Thailand, the first the tropical storm “LIONROCK (2117)” made landfall over the upper Vietnam on October 10, it respectively downgraded into the low pressure cell covering northeastern part of Thailand on October 11 and the second was tropical cyclone “KOMPASU (2118)” which dissipated over Vietnam on October 14. These conditions brought abundant rainfall in majority areas of Thailand and flash floods was reported in several places. Monthly rainfall was above normal in most parts of Thailand i.e. northern part 65.8 mm (53%) and northeastern part 70.3 mm (60%), central part 21.2 mm (11%), eastern part 104.5 mm (46%) and southern part (west coast) 48.2 mm (13%) while below normal was found in southern part (east coast) 46.8 mm (18%). The average rainfall over the whole area of Thailand was 26 percent higher than normal. Meanwhile the high pressure area from China extended its ridge to cover upper Thailand and replenishment of the easterly and southeasterly winds prevailed over Thailand. These caused decreasing temperature in several areas and cool weather mainly in northern and northeastern parts. More details on the weather are as follow:October 2021 was dominated by the monsoon trough which lay across upper Thailand during the beginning and the middle of the month and it occasionally moved southwards to lie over the upper southern and eastern parts coupled with the active southwest monsoon prevailed over the Andaman Sea, Southern part and the Gulf of Thailand during the same period. Moreover there were 2 tropical cyclones having some effects of rainfall on Thailand, the first the tropical storm “LIONROCK (2117)” made landfall over the upper Vietnam on October 10, it respectively downgraded into the low pressure cell covering northeastern part of Thailand on October 11 and the second was tropical cyclone “KOMPASU (2118)” which dissipated over Vietnam on October 14. These conditions brought abundant rainfall in majority areas of Thailand and flash floods was reported in several places. Monthly rainfall was above normal in most parts of Thailand i.e. northern part 65.8 mm (53%) and northeastern part 70.3 mm (60%), central part 21.2 mm (11%), eastern part 104.5 mm (46%) and southern part (west coast) 48.2 mm (13%) while below normal was found in southern part (east coast) 46.8 mm (18%). The average rainfall over the whole area of Thailand was 26 percent higher than normal. Meanwhile the high pressure area from China extended its ridge to cover upper Thailand and replenishment of the easterly and southeasterly winds prevailed over Thailand. These caused decreasing temperature in several areas and cool weather mainly in northern and northeastern parts. More details on the weather are as follow: