The Eastern Cape had temperatures so high on Friday that they were almost hazardous to health, the South African Weather Service said.
"Both Port Elizabeth and East London are at around a discomfort index of 107," said spokesperson Garth Sampson, adding that an index of 110 is hazardous to health.
When temperature and humidity are both high, the body cannot cool itself adequately by sweating. The discomfort index is a measure of this.
"People should not engage in vigorous outdoor activities as some areas along the coast might have reached 110 already. Special care should be taken to keep the sick and elderly people cool," said Sampson.
In Uitenhage, the temperature was 40,2 degrees Celsius, while Somerset East recorded 40,7. In East London and Port Elizabeth, the temperatures were above 35 degrees Celsius.
"The good news is the wind should turn west by 3pm, bringing instant relief in Port Elizabeth.
"But East Londoners will have to wait until around 5pm when the wind will change in that area, bringing the temperatures down," Sampson said.
Meanwhile, the Herald newspaper reported on Friday that dozens of fires had destroyed large tracts of veld in the Nelson Mandela metropolitan area as a result of the heat wave.
The high temperatures are wreaking havoc on agricultural production, with farmers saying if good rains do not come soon, a crippling drought is imminent.
"The blistering heat has caused a string of veld fires in the past two days, with firefighters, in Nelson Mandela Bay in particular, working around the clock fighting runaway fires sparked by the heat and dry weather."
At least 55 veld fires have been reported in and around the city in the past two days, the newspaper reported.
Weather officials said it is normal at this time of the year to experience hot conditions and very little rain. The rest of the country has also been experiencing hot conditions, Sampson said, adding that it will be cooler on Friday night.
"On Saturday it would be warm with maximum temperatures in most parts of the country at 25 degrees Celsius."
He said the temperatures are expected to rise in the whole country by Sunday.
"The temperatures had been high in the country for the past week, with Cape Town also reaching 40 degrees Celsius. The heat will cool off tomorrow [Saturday] but start heating up again on Sunday." -- Sapa
