Get your summer gear ready. This weekend will be as if someone has flicked the switch on a heater.
After a cold and wet October, temperatures of up to 30degC will arrive in Otago for the first weekend of November.
Niwa forecaster Ben Noll said significantly warmer temperatures would spill on to the South Island tomorrow and continue until Monday.
"Maximum temperatures will eclipse 30degC for the first time this spring in parts of the South Island, like Otago, Canterbury, and Marlborough.
"Some records may also tumble," he said.
New Zealand's hottest November temperature on record occurred at Lake Coleridge, in Canterbury (35.6degC in 1920), followed by Gisborne (34.8degC in 2016).
At the moment, MetService is forecasting 30degC for Alexandra tomorrow and 29degC on Sunday.
Wanaka can expect 29degC and 27degC respectively, while Queenstown, Dunedin, Oamaru, Gore and Invercargill will reach the mid-20s over the weekend.
"The warmth will be spurred on by a hot air mass moving across the Tasman Sea from Australia, which has experienced ongoing, long-term drought conditions," Mr Noll said.
During the second week of the month and continuing into mid-November, some strong fronts are possible in the South Island, bringing rounds of heavy rain and an increased risk for areas of flooding, especially to the west of the Southern Alps.
However, the long-term forecast for November, December and January shows temperatures are equally likely to be near average or above average across coastal Otago, and near average in inland Otago and Southland.
Across the southern region, rainfall totals are about equally likely to be near normal or above normal, and soil moisture levels and river flows are likely to be near normal or below normal, he said.
