Periods of heavy rain could hit the East Coast particularly, she said.
“Some certain spots might get very heavy rain.”
Thunderstorms were possible by Friday afternoon.
Despite average overnight temperatures yesterday evening, temperatures tonight could reach around 20C.
Martino encouraged people to keep an eye on the forecast.
Now was a good time to clear gutters and get organised, she said.
The Advocate reported yesterday that residents in storm-hit areas of the region were battening down the hatches.
Ōakura resident and Civil Defence volunteer Kylie Rogers said locals wanted to be prepared in case heavy rain fell, and were cleaning out drains and making sure animals were safe.
Brodie Stone covers crime and emergency for the Northern Advocate. She has spent most of her life in Whangārei and is passionate about delving into issues that matter to Northlanders and beyond.