The country will be in the grip of sweltering heat on Saturday with the mercury expected to hit a scorching 44C in the North, according to the weather bureau.
As a result, the Meteorological Department is warning people to stay indoors, particularly the elderly and those prone to heatstroke.
The department said the heat could trigger gusty winds in many areas and freak storms. People should avoid standing under large trees and billboards which are not structurally secure.
The North is predicted to be hit hardest by the heat with temperatures hovering between 39-44C. There is a 10% chance of rain and strong winds in parts of Chiang Rai, Phayao, Nan, Uttaradit, Kamphaeng Phet, Phichit Phitsanulok and Phetchabun.
The Northeast is also likely to experience highs of between 39-40C, as is the Central Plains provinces, where the temperature could rise to 42C in some localities.
In the East and the South, the maximum temperatures are forecast to be between 37-40C, according to the department.
Bangkok is also in for baking hot weather fuelled by highs of 37-40C.
In Lampang yesterday, the authorities were handing out new corrugated zinc sheets for the repair of house roofs torn off by a freak storm which ravaged wide areas of tambon Mae Phrik, in Mae Phrik district yesterday.
More than 50 houses were affected. Some also sustained damage from hailstones, according to the local disaster mitigation office.
In Phaisali district of Nakhon Sawan, heavy rain and hailstones -- some as big as marbles -- pounded houses for hours.
Phayao Boonkham, of Ban Mai Kradonepom in Phaisali, said she and her family fled their home when it was battered by hail and had the roof blown off.
In the northeastern province of Nakhon Ratchasima, shops and houses were damaged and vehicles hit by falling trees when strong winds and heavy rain pummeled Phimai municipality.
Residents and local officials could be seen hard at work yesterday morning cleaning up streets and making repairs to damaged buildings.
Wind and rain pounded the municipality's evening markets during peak time, striking suddenly when residents were shopping around 6.30pm.
Phimai district chief Lertphan Sinbanlengsanoi and mayor Danai Tangjurdja said at least 100 houses and shops were damaged. Some big trees around Phimai Historical Park fell on parked vehicles and shops in the area.The park was not damaged, and there were no reports of injuries.