The South Island was sizzling on Thursday with Christchurch experiencing its hottest day of the summer.
Much of the South Island got to temperatures close to or above 30C, while two towns south of Christchurch - Leeston and Southbridge - reached 34.4C.
Most of the North Island was also hot, with many places hovering around 25C.
In MetService's morning update, Milford Sound was the only place not expected to reach 20C or above on Thursday, with its high expected to be 19C.
NIWA's UV index shows extreme levels of UV were expected in most parts of New Zealand on Thursday from about midday.
Kiwis should remember to slip, slop, slap and wrap to prevent a sunburn.
A front was expected to bring rain to the south of the South Island later on Thursday with a low risk of thunderstorms for northern Fiordland and far southern Westland.
Fire danger was also elevated.
Find more weather information on Newshub's weather page.
