The big dry is hitting parts of the country hard, with some areas receiving less than 5 per cent of their normal January rainfall to date.

NIWA statistics show just how serious the situation is in some areas. In the far north, Kaitaia has had 4 millimetres out of a normal 89mm for the month, Auckland 6mm compared 61mm, Tauranga 4mm compared to 78mm, and Hamilton 11mm instead of 82mm.

In contrast Christchurch, which has had many long, scorching hot days, has received near-normal January rainfall of 37mm, Dunedin is not much below normal with 67mm, and recently balmy Wellington is nearly 20 per cent above normal with 88mm.

At Mt Cook a whopping 1018mm fell in January, compared to 423mm normally.

However, despite the near-normal rainfall, Christchurch and Dunedin appear on course to record quite a bit more sunshine than usual for January.

At the end of Sunday, with four fine days of the month to go, Christchurch was already above the normal 238 hours of sunshine for the whole of January, with 249 hours.

Just to the north, Rangiora had clocked up 269 hours, compared to the usual 200, while Dunedin had 192 hours - above the normal 180 hours.

In contrast, Auckland and Wellington still had to catch the monthly average, with Auckland at 207 of the normal 233 hours, and Wellington at 209 of the usual 247.

Standouts for mean temperature included Napier, which was 0.9C above average at 19.7C, and Turangi, which was 1.5C below average at 13.2C.

This week Central Otago and Taumarunui are in line for a run of days with temperatures reaching at least 30C as a spell of settled, sunny weather continues over the country.

MetService is forecasting Taumarunui will reach 32C today and 31C on each of the following three days, after it climbed to 31.3C yesterday.

Wanaka, with 30.7C yesterday, is forecast to reach at least 30C today and for the following four days, while Alexandra is expected to reach 31C today and 32C on the following three days, after getting to 31.9C yesterday.

NIWA data shows runs of five days with 30C temperatures are not that unusual in Central Otago, but are less common for Taumarunui.

Records for Taumarunui going back to 1947 showed two previous instances where the temperature reached 30C for at least five days in a row, and one near miss.

In Alexandra, NIWA has recorded eight sequences in data going back to 1930 where the temperature reached 30C on at least five days in a row. That included two seven-day sequences, in January 1956, and January and February 2005. 

- © Fairfax NZ News