The heatwave which started on Friday will decline across most parts of the country, as Egypt's Meteorogical Authority (EMA) reports.
Temperatures are expected to decline in the north on Sunday, with pleasant weather along the Red Sea coast, according to the EMA.
Cairo and the Nile delta will experience warm weather, with temperatures remaining high in Upper Egypt.
Visibility in the northern region of the country will be limited in the early hours due to morning mist.
On Saturday, temperatures in Cairo reached 40 degrees Celsius, whilst Aswan in Upper Egypt saw 45.
According to EMA's forecast, Cairo and Nile Delta will see average highs of 37 degrees and lows of 26, while Alexandria and Marsa Matrouh on the Mediterranean coast will see a high of 29 degrees and a low of 22.
Highs of 29 degrees are expected in North Sinai, with lows of 24 degrees, while South Sinai will see a high of 39 degrees and a low of 21 degrees.
North Upper Egypt will witness average highs of 38 degrees and lows of 29 degrees, while southern Upper Egypt will struggle with highs around 46 and lows in the mid-twenties.