Weak high pressure is affecting the area, the met office said on Sunday adding that there will be dust in the atmosphere.
In its early morning weather forecast, the met office said that Sunday will be mainly fine with intervals of increased mainly high cloud.
Temperatures will be 29 C inland, 27 on the east coast, around 24 C on the remaining coasts and 22 C in the higher mountains.
Tonight will be mainly fine with increased cloud at intervals. Temperatures will fall to 15 C inland and on the coasts and around 12 C in the mountains.
Monday, Tuesday and Wednesday will be mainly fine, but there will be increased mainly high cloud on Wednesday.
Temperatures will rise gradually by Tuesday remaining the same on Wednesday, which is above average for the time of year.