An explosive cyclogenesis - known as a “weather bomb” - is when a low develops quickly, often associated with intense weather near it.
However, the impact depended on where it developed, and at this stage the low looked to be remaining well offshore, Makgabutlane said.
“It’s only the rain on its outer edge that looks to brush over the North Island.”
The extent of the rain would depend on the east or westward movement of the low, she said.
“So it will pay to keep an eye on the forecast over the next few days as things develop. We will continue to monitor its development and issue any severe weather information as necessary.”
The worst of the weather is expected in parts of the upper North and South islands from tomorrow night. Rain will steadily worsen in the northern North Island as the day goes on.
“As [tomorrow] continues, the rest of the North Island can also expect a little bit of that rain starting to drift down. And in the western South Island as well.
“But for the lower and eastern South Island, it looks like it should be continuing to remain fairly dry.”
Parents keen to get housebound kids outside have a short window on Sunday.
“The first part of Sunday is looking probably the best of the day, for most places, [and] into the afternoon. Then we’ve got the next weather feature that starts to move across the latter part of Sunday.
“It looks like it will be bringing a return of some showery weather, especially for the North Island and parts of the South Island.”
- Additional reporting by Cherie Howie