Weak low pressure is affecting the area and there will be dust in the atmosphere today, the met office said in its early morning weather bulletin.
It said that on Sunday there were will be intervals of increased high cloud. Temperatures will be 37 C inland and around 30 C on the coasts and in the mountains.
There will be intervals of increased high cloud tonight and temperatures will drop to 19 C inland and on the coasts and 17 C in the mountains.
On Monday, Tuesday and Wednesday there will be increased high cloud. Temperatures are expected to remain the same on Monday, edging down on Tuesday and Wednesday but remaining above average for the time of year.