11 July 2024

Thailand is facing “extreme” rainfall from August until October, as La Niña is about to set in after the end of the El Niño phenomenon in May, according to Somkuan Tonjan, director of the Central Weather Forecast Division of the Meteorological Department.

He said that Thailand is currently in the neutral period, during June and July, between the end of El Niño until the arrival of La Niña in August, during which weather fluctuations are prevalent, with light rain on some days, heavy rain on the other days or no rain for a couple of days, despite the fact that Thailand has officially entered the rainy season.

A mild La Niña is forecast to set in at the end of July, which will then intensify, resulting in more rain and even “extreme” rainfall, said Somkuan.

He explained that “extreme” rainfall means more than 100mm in 24 hours, adding however that heavy rain in Thailand is normally measured at 90-100mm in 24 hours.

This year, though, he predicts that rainfall in some areas in the northern, north-eastern, central and eastern regions may be as high as 150mm in 24 hours, which is referred to as “extreme” rain.

During the transition period from El Niño to La Niña, Somkuan said that more storms are predicted, most of which will weaken before arriving in Thailand, but they will bring more rain.

He said that the number of rainy days are expected to decrease this year, but days with heavy rain are likely to increase.