Sweating days and sleepless nights

Construction workers fight yesterday's heat and humidity with water bottles and a shady tree. Photo / Sarah Ivey

Aucklanders and other North Islanders stifled by the heat should sleep easier from tomorrow - tonight should be the last in a run of extremely stuffy nights.

On Tuesday, the overnight temperature in Auckland did not fall below 20C, and humidity has been hovering at close to 100 per cent, sparking a rush of grumbling yesterday on social networks such as Facebook and Twitter.

MetService forecaster Ramon Oosterkamp said the extremely humid air would be gone by tomorrow after hanging around for close to a week.

The air had been sodden, but "that is going to change on Friday when a cold front marches north over the country and sweeps all this high humidity air off to the north", he said.

After some brief rain tomorrow, the weekend weather should be fine, with cooler nights of about 12C to 14C.

Mr Oosterkamp - who works in Wellington - said the humidity had been caused by "air that has come down from the tropics and has dragged itself over you guys".

"We've had quite a warm moisture feed that's come from Queensland way and has been dragged over ... northern New Zealand, while you've got a ridge of high pressure over the South Island."

He said it was not unusual for Auckland to have humid weather at this time of year, and joked that Aucklanders should stop complaining, as Wellington had hardly experienced summer this year.

"Can we have some of your toastiness, please?"

The humid nights may not be over for the year. Records over the past 30 years show humidity worse on average in March than in February in Auckland, Whangarei, Tauranga, Rotorua and Taupo.

Humidity of 100 per cent means the air is saturated and sweat cannot evaporate, making it hard to cool down.

Mr Oosterkamp said that while exercising to encourage sweating could help, when humidity was very high, those without air conditioning largely had to "grin and bear it".

Weatherwatch analyst Philip Duncan said Auckland was the hottest centre yesterday with a temperature of 28C and a humidex, or "feels like", temperature of 35C.

In Whangarei, the humidex was 32C and in eastern Coromandel and Waikato it was around 33C.

HOW TO BEAT THE HEAT

* Drink lots of water - more than you think you need.
* Avoid drinking alcohol, coffee or cola and eating heavy meals.
* Dress right - wear light and loose-fitting clothing.
* Fan yourself or get into a breeze, although skin temperature is 32C, so once the air temperature passes 28C, this has little effect.
* Slow down and seek the shade. Shun the sun and close the curtains.
* Take a trip to air-conditioned places - shopping malls, theatres or community centres.
* Take a dip or a cool shower. Wear something cool and wet.

Source: MetService.com