Provinces in upper Thailand are warned of possible summer storms on Sunday and Monday, May 5-6, according to the 5am announcement of the Thai Meteorological Department on Sunday.
The summer storms are caused by the high pressure system covering the South China Sea and the southerly winds prevailing across the lower North, Northeast, Central and East regions.
Thunderstorms, gusty winds and hail are forecast.
Provinces expected to be affected on Sunday, May 5:
North: Phrae, Nan, Lamphun, Lampang, Tak, Sukhothai, Uttaradit, Kamphaeng Phet, Phichit, Phitsanulok and Phetchabun.
Northeast: Loei, Nong Bua Lamphu, Udon Thani, Nong Khai, Bueng Kan, Sakon Nakhon, Nakhon Phanom, Kalasin, Mukdahan, Maha Sarakham, Khon Kaen, Chaiyaphum, Nakhon Ratchasima, Buri Ram and Surin.
Central: Nakhon Sawan, Lop Buri, Saraburi, Uthai Thani, Chai Nat, Sing Buri, Ang Thong, Ayutthaya, Suphan Buri, Kanchanaburi, Ratchaburi and greater Bangkok.
East: Nakhon Nayok, Prachin Buri, Sa Kaeo, Chachoengsao, Chon Buri, Rayong, Chanthaburi and Trat.
North: Tak, Sukhothai, Uttaradit, Phitsanulok, Kamphaeng Phet, Phichit and Phetchabun.
Northeast: Loei, Nong Bua Lamphu, Udon Thani, Nong Khai, Bueng Kan, Chaiyaphum, Khon Kaen, Nakhon Ratchasima, Sakon Nakhon, Nakhon Phanom, Mukdahan, Yasothon, Amnat Charoen, Si Sa Ket and Ubon Ratchathani.
Central: Nakhon Sawan, Lop Buri, Saraburi, Uthai Thani, Kanchanaburi and Ratchaburi.
East: Nakhon Nayok, Prachin Buri, Sa Kaeo, Chachoengsao, Chon Buri, Rayong, Chanthaburi and Trat.