Surface flooding is being reported around Tauranga this morning as heavy rain pummels the city.

A SunLive reader driving into work this morning says there is some slight flooding on Takitimu Drive, as you head from Bethlehem to Tauranga.

"It it not as bad as it has been in the past, but motorists should be mindful of it if they have to drive today."

A severe weather warning for heavy rain, which the MetService issues yesterday, remains in place this morning.

According to the weather organisation, people can expect heavy rain for most of the day with thunderstorms possible this afternoon.

Rain is expected to ease to showers in the evening, with strong northeasterlies also easing this evening.

Image: MetService.

A thundersorm watch is also in place for the Waikato and Coromandel.

The MetService says a frontal system and associated heavy rain is expected to move south over Auckland, Coromandel Peninsula and the far north of Waikato this morning.

"There is a moderate risk of thunderstorms embedded in the rain.

"These thunderstorms are expected to bring heavy rain with intensities of 15 to 25 mm/h, and strong winds gusting 90 to 110km/h.

"Additionally some of these thunderstorms could become severe, producing localised downpours of 25 to 40mm/h, as well as localised torrential rain with intensities greater than 40mm/h. There is also a risk of a localised tornado occurring.

"Downpours and torrential rain can cause surface and/or flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips.

"Driving conditions could be hazardous with surface flooding and poor visibility in heavy rain.

"While possible tornadoes may cause some structural damage, including damage to trees and power lines, and make driving hazardous. If any tornadoes occur, they will only affect very localised areas."