The Department of Meteorology has issued a yellow warning for extremely high temperatures for Friday, July 17.
The warning takes effect at 2pm and will remain in force until 4.30pm.
The weather on Friday will be mainly fine, though increased cloud will appear over the mountains in the afternoon.
The temperature will rise to around 40 degrees inland, around 35 degrees on the southern, eastern and northern coasts, around 32 degrees on the western coast, and around 30 degrees in the higher mountains.
Outlook
On Saturday and Sunday, most areas will remain mostly clear with periods of increased cloud, though cloud developing over the mountains after midday is expected to bring isolated rain or a thunderstorm. Temperatures are not expected to change significantly through Sunday, continuing to run above normal for the season.