The Meteorological Department issued a storm warning early on Monday saying Thailand's upper region will face thunder storms, gusty winds, lightnings, and freak storms in some areas, starting today.
Bangkok is also expected to be slammed by summer storm, it said.
It said the summer storms are expected from the approaching of another round of high pressure system from China that has covered Thailand's Northeast, and is expanding to blanket the whole upper region today.
The department issued the warning at 5.00am saying summer storms will be expected today, first in the Northeast, North and East.
The summer storms, it said will come with thunder storms, gusty winds, lightnings with freak storms in some areas.
The storms are expected to slam the upper region, including Bangkok and surrounding provinces, beginning today.
It told people to avoid outdoor activities, keep off huge and unstable bill boards, large trees.
Farmers were also told to make preparations to prevent damages to their crops.
Affected provinces in the North from April 16-17 are:
Chiang Mai, Chiang Rai, Lamphun, Lampang, Phayao, Phrae, Nan, Uttaradit, Phitsanulok, Sukhothai, Kanphaengpet, Phichit, Tak, and Phetchabun.
Northeast provinces to be affected include Loei, Ning Bualampoo, Udon Thani, Nong Khai, Bung Kan, Sakhon Nakhon, Nakhon Phanom, Mukdaharn, Chaiyaphum, Khon Kaen, Nakhon Ratchasima, Kalasin, Maha Sarakham, Roi-et, Yasothorn, Amnat Charoen, Ubon Ratchathani, Sisaket, Surin and Buriram.
The central provinces are Nakhon Sawan, Lopburi, Saraburi, Ayutthaya, Uthai Thani, Chai-nat, Singburi, Ang Thong, Bangkok and surrounding provinces.
Eastern provinces are Nakhon Nayok, Chachoengsao, Prachinburi, Srakaew, Chonburi, Rayong, Chanthaburi, and Trat.
Meanwhile the easterly wind that is blowing into the South and the Gulf of Thailand will be strengthened during April 17-19. This will bring increased rains in the South, and high waves of 2 mettes in the Gulf and the Andaman Sea. Small boats are advised to navigate with caution.
Source: Thai Public Broadcasting Service (ThaiPBS)