A severe thunderstorm watch for the Coromandel Peninsula is expected to be in place until 7pm on May 9.
Metservice said the thunderstorm may bring torrential rain in excess of 40 millimetres per hour to the area.
“Rainfall of this intensity can cause surface and/or flash flooding, especially in low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips,” Metservice said.
“Driving conditions will also be hazardous with surface flooding and poor visibility in heavy rain.”
Metservice said “damaging” wind gusts exceeding 110 kilometres per hour were also possible and could lead to tornadoes.
“Wind gusts of this strength can cause some structural damage, including trees and power lines,” Metservice said.
“If any tornadoes occur, they will only affect very localised areas.”
Visit www.metservice.com/warnings for updates.