Aucklanders are being advised to be considerate of their colleagues as they return to work tomorrow, with a hot, sticky – and potentially sleepless – night in store.

The City of Sails is forecast to reach 29C tomorrow, with an overnight temperature tonight of 20C, which MetService meteorologist Clare O’Connor said could make getting a good sleep rather difficult.

“Be extra nice to everyone tomorrow morning when you get into work, because there may not be a lot of sleeping going on with those temperatures.”

Today, conditions across the country are mostly fine apart from Northland, Fiordland and Southland, which are expected to get rain.

Fiordland is under a heavy rain watch until 3pm tomorrow.

O’Connor said 100mm is predicted to fall in that period.

The watch has a moderate chance of being upgraded to a warning.

Tomorrow and Tuesday will see a big contrast in temperatures for the South Island’s east coast, with Christchurch forecast to get 28C tomorrow but a high of only 18C the following day.

In the North Island, everywhere but the east coast regions of Gisborne, Hawke’s Bay and Wairarapa are expected to get some rain tomorrow.

Tuesday will be more of the same, but the East Coast will get some cooler and wetter weather, O’Connor said.

Severe weather watches

Like Fiordland, Canterbury and Westland have also had heavy rain watches issued.

The watch for Westland south of Franz Josef Glacier comes into effect at 6am tomorrow and lasts until 9pm the same day.

Weather watches in place for parts of the South Island. Photo / MetService

Marlborough south of Seddon and Canterbury north of the Rangitata River are under the watch on Tuesday from 2am-10pm.

MetService has warned that periods of heavy rain could approach warning criteria, with precipitation possibly falling as snow above 1200m in Canterbury.

Both watches have a moderate chance of being upgraded to a warning.