Upper Thailand has been warned of summer storms throughout the weekend due to a high-pressure front moving in from the South China Sea.
The Meteorological Department said storms could take place across the North, the Northeast, the East and the Central Plains on Saturday and Sunday.
Moisture from the Gulf of Thailand and the South China Sea is being pushed by the high-pressure system onto the mainland. As it mixes with hot air, rainstorms and even hail can be expected.
On Saturday, summer storms are expected to affect six provinces in the North (Nan, Uttaradit, Tak, Phichit, Phitsanulok and Phetchabun); 18 provinces in the Northeast (Loei, Nong Khai, Bueng Kan, Sakon Nakhon, Nakhon Phanom, Nong Bua Lamphu, Udon Thani, Chaiyaphum, Khon Kaen, Kalasin, Maha Sarakham, Roi Et, Yasothon, Mukdahan, Amnat Charoen, Nakhon Ratchasima, Buri Ram and Surin); 14 provinces in the Central Plains including Greater Bangkok (Nakhon Sawan, Uthai Thani, Chai Nat, Sing Buri, Ang Thong, Lop Buri, Saraburi, Suphan Buri, Ayutthaya, Kanchanaburi, Ratchaburi, Nakhon Pathom, Samut Sakhon and Samut Songkhram); and four provinces in the East (Nakhon Nayok, Prachin Buri and Chon Buri).
Areas expected to be affected on Sunday include 11 provinces in the North (Mae Hong Son, Chiang Mai, Lamphun, Lampang, Sukhothai, Uttaradit, Tak, Kamphaeng Phet, Phichit, Phitsanulok and Phetchabun); 14 provinces in the Central Plains including Greater Bangkok (Nakhon Sawan, Uthai Thani, Chai Nat, Sing Buri, Ang Thong, Lop Buri, Saraburi, Suphan Buri, Ayutthaya, Kanchanaburi, Ratchaburi, Nakhon Pathom, Samut Sakhon and Samut Songkhram); and four provinces in the East (Nakhon Nayok, Prachin Buri, Chachoengsao and Chon Buri).
In the event of heavy rain, people are advised against being out in the open or under large trees and unsecured structures, and farmers may sustain some damage to their crops.
Air quality in Thailand on Saturday afternoon. (Screenshot: IQAir)
The precipitation, however, is expected to alleviate the current severe air pollution, which in Chiang Rai has resulted in 41 people being sent for emergency medical care.
Particulate matter levels in the northern province measured between 200 and 350 microgrammes per cubic metre on Saturday morning, exacerbated by three forest fires in Mae Chan district this past week.
Provincial health authorities reported that after setting up 444 clean rooms in medical facilities to treat people affected by the situation, over 7,000 patients have sought aid for respiratory illnesses.
Officials say they hope that rainy conditions will help alleviate the PM2.5 build-up but they plan to keep up efforts to reduce dust, such as running water sprinklers out of public and private buildings.
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