Monday will be mainly fine with temperatures inland at 39 C, around 33 C on the south, east and north coasts and 31 C on the west coasts and in the mountains.
Tonight will be mainly fine, but increased low cloud is expected on the north and west coasts.
Temperatures will fall to 25 C inland and on the south and east coasts, around 23 C on the west and north coasts and around 20 C in the mountains.
Tuesday, Wednesday and Thursday will be mainly fine, with patchy clouds at intervals in the afternoon in the mountains.
Temperatures are expected to remain at the same levels over the next three days at close to average for the time of year on the coasts but a little above average in the interior and in the mountains.