Hawke's Bay hit by 602 lightning strikes on Sunday, another severe thunderstorm warning today

Lightning over Hastings in October, 2019. Photo / Warren Buckland

More than 600 lightning strikes were recorded across Hawke's Bay on Sunday, and there were more on their way on Monday evening.

A severe thunderstorm warning was in place for northern Hawke's Bay from 2pm to 10pm on Monday, with forecasters warning travellers to expect localised flooding, particularly in coastal areas.

It's a "rinse and repeat" of Sunday, where 602 lightning strikes hit the region between midday and 5pm and a severe thunderstorm warning was in place over almost the entire region.

There were few photos of the event in the Twin Cities, but social media commenters noting they spotted "one or two" in Central Hawke's Bay when a thunderstorm rumbled through.

In Dannevirke, there was localised flooding and a significant number of strikes.

MetService meteorologist Andy Best said there was no way their instruments could have been mistaken and the 600 lightning strikes were definitely "real".

Some of them might not have reached the ground, and some could have struck in remote areas, he said.

Those heading back to the Twin Cities as part of the annual summer holiday commute home should be prepared for the conditions and should stay up-to-date with the latest warnings on the MetService's website, he said.

Meteorologist Tom Adams said thunderstorms are localised: one place can get drenched and 1km down the road it can be fine.

"It's impossible to forecast exactly the co-ordinates a thunderstorm will hit ahead of time, they are too erratic for that," he said.

According to Adams, it's only when they form that they can track the storm and issue a warning if necessary.

Temperatures across the region will remain in the mid-20s throughout the week.

Adams said warm subtropical air is being pulled down by a low-pressure weather system over the South Island, bringing warm and humid air to the region – which "adds fuel to the thunderstorms".

However, Adams added the risk of thunderstorms will reduce as the week progresses.

Tuesday will be fine for Napier, Hastings and Wairoa – with Waipukurau potentially receiving the odd isolated shower.

On Wednesday, the region is forecast to have sunshine and temperatures between 24C and 27C.

Thursday and Friday are expected to be fine with light cloud and temperatures in the mid-20s across Hawke's Bay.