Authorities urged Israelis to exercise caution due to an extreme heat wave expected to hit the country on Wednesday, raising temperatures by as much as 20 degrees in some areas of the country until Saturday.

Temperatures in the more temperate Judean hills are expected to reach 97 degrees Fahrenheit, while the heat is set to reach a scorching 116 degrees in the Dead Sea region.

With the yearly Lag B’Omer holiday beginning with customary bonfires on Wednesday night, Israel’s Fire and Rescue Service placed a ban on lighting fires in any forests, reserves or parks, even in designated areas.

The Israel Nature and Parks Authority urged the public to refrain from engaging in any exertion outdoors, including long walks, until Friday evening.

“The Health Ministry calls upon the general public, the elderly population and chronically ill patients, to … avoid exposure to heat and sun as much as possible, avoid unnecessary physical exertion, make sure to drink water and stay in air-conditioned places as much as possible,” it said in a statement.

In 2016, nearly 400 people were treated for heat-related medical issues when May temperatures rose as high as 115 degrees in Eilat and 99 degrees in Jerusalem.