Scattered summer storms, gusty winds and some hail are forecast for Bangkok and provinces in the North, Northeast, East and Central Plains on Tuesday and Wednesday.
A moderate high pressure system will cover northeastern Thailand and the South China Sea over the two days, the weather office said.
Hot to very hot weather will affect the upper regions, with strong southerly and southeasterly winds bringing humidity from the Gulf and the South China Sea, the Meteorological Department said.
With these conditions, scattered summer storms could bring strong winds, isolated hail and lightning strikes to many provinces in the North, Northeast, East and Central Plains, including Bangkok and its vicinity, on Tuesday and Wednesday.
On April 25, forecast affected areas are 11 provinces in the North (Chiang Mai, Chiang Rai, Lamphun, Lampang, Nan, Phrae, Uttaradit, Tak, Kamphaeng Phet, Phitsanulok and Phetchabun); 15 provinces in the Northeast (Loei, Nong Khai, Bueng Kan, Sakon Nakhon, Nakhon Phanom, Chaiyaphum, Khon Kaen, Mukdahan, Yasothon, Amnat Charoen, Nakhon Ratchasima, Buri Ram, Surin, Si Sa Ket and Ubon Ratchathani); 6 provinces in the Central Plains (Nakhon Sawan, Kanchanaburi, Ratchaburi, Uthai Thani, Lop Buri and Saraburi); and all eight eastern provinces.
On April 26, forecast affected areas are 15 provinces in the North (Mae Hong Son, Chiang Mai, Chiang Rai, Lamphun, Lampang, Phayao, Nan, Phrae, Uttaradit, Tak, Sukhothai, Kamphaeng Phet, Phichit, Phitsanulok and Phetchabun); 15 provinces in the Northeast (Loei, Nong Khai, Nong Bua Lamphu, Udon Thani, Chaiyaphum, Khon Kaen, Mukdahan, Maha Sarakham, Roi Et, Yasothon, Amnat Charoen, Nakhon Ratchasima, Buri Ram, Surin, Si Sa Ket and Ubon Ratchathani); 14 provinces in the Central Plains (Nakhon Sawan, Uthai Thani, Chai Nat, Kanchanaburi, Ratchaburi, Suphan Buri, Lop Buri, Saraburi, Sing Buri, Ang Thong, Ayutthaya, Samut Songkhram, Samut Sakhon and Nakhon Pathom); Bangkok and its vicinity; and all eight provinces in the East. (continues below)
The weather agency advised people to avoid risky outdoor places during severe weather - such as big trees, unsecured structures and billboards - and not to wear metal and avoid using mobile phones during storms.
Farmers were advised to try and protect their crops from storm damage.
The department said the easterly and the southerly winds prevail across the Gulf of Thailand and the Andaman Sea with isolated thundershowers in the west coast of the South. Waves in the Gulf are forecast to be about one metre high and more than 2 metres high during thundershowers. All shipping should proceed with caution.
In Nakhon Phanom, more than 700 houses were damaged when storms hit parts of five districts in this northeastern provinces on Saturday and Sunday.
The affected districts were Renu Nakhjon, Pla Pak, Renu Nakhon, Muang and That Phanom district. The worst hit district was That Phanom, where more than 300 houses were damaged.
In Khon Kaen, fierce storms hit many areas in Phra Yuen district on Sunday, damaging more than 250 houses in the district. Some big trees were uprooted and a large billboard fell down.
