Unusually balmy nights for this time of year are to continue for the rest of the month.
MetService meteorologist Ciaran Doolin said May is poised to be warmer than it has been in previous years, with temperatures expected to be 1.5-2C higher on average than are typical for this time of year.
"It's going to be an extremely mild May for most of the regions.
"There's a possibility of frosty spells but the number of southerlies will be low."
Today there are a few severe weather warnings in place across the country.
Kapiti and Tararua can expect a burst of heavy rain this morning and early afternoon, with 60-90mm expected to accumulate.
Mt Taranaki is also in for a dousing this morning, which is predicted to continue after midday.
"The rain will slowly move north but it should clear for most of the North Island," Mr Doolin said.
The South Island can expect a mainly fine day.
Rain is clearing in Nelson, Marlborough and Buller, and Canterbury, Otago and Southland will be mostly sunny.