Weather: 'Abnormally warm temperatures' cook New Zealand this week

New Zealanders are bracing for another week of scorching heat as "abnormally warm temperatures" cook the country.

"An enormous high pressure system (anticyclone) is crossing New Zealand this week, bringing warmer than normal daytime highs pushing up to 30degC for some areas in the days ahead," Weather Watch warns.

Head forecaster Phillip Duncan says it's connected to what's happening in Australia, with a monster high now stretching from Fiji to Sydney to New Zealand.

The "record-breaking heat" across the Tasman pushed temperatures in Hobart to 38degC on Saturday, its hottest day in March since 1940.

"Adelaide (41degC) and Melbourne (37degC) were also feeling the heat yesterday as a trough ahead of a front funnels heat from the interior towards the southeastern capital cities," Weather Watch says.

And it's now set to push up temperatures around New Zealand, with inland areas forecast to be the worst affected.

"The most unusually warm temperatures (when compared to average for the time of year) will occur on the South Island," NIWA says.

"The warmest days will have max temps well in the 20s and possibly flirting with 30degC."

The high will continue to block rainmakers and colder weather, although there could be relief for drought-affected regions later in the week.

"By the end of the week much of the country will have a sub-tropical northerly flow which might help spark a few showers around Thursday and Friday in some of our driest regions," Weather Watch says.

"The wet weather isn't locked in but looks as though showers are quite likely in western and northern New Zealand later this week."

Newshub.