UPDATE 3.55pm: The severe thunderstorm alert for the Bay of Plenty has been lifted.
The alert this morning was the third severe weather warning this week and was expected to ease by this evening.
The heavy rain overnight and this morning resulted in the cancellation of the University of Waikato graduates' parade and the early closing of Otumoetai College due to flooding.
UPDATE 1.30pm: A second severe thunderstorm watch has been issued for the Bay of Plenty this afternoon, following a heavy downpour overnight and more this morning.
The heavy rain alert is the third for severe weather this week and is expected to ease by this evening.
In addition to the heavy rain there is a risk of thunderstorms with rainfall rates reaching 25 to 35 mm/hr.
EARLIER at 7.51am: A severe thunderstorm watch has been issued for the Bay of Plenty this morning.
The watch follows one for heavy rain that was issued yesterday for last night and today.
The Metservice alert comes as a rainband moves to the northeast of the North Island this morning. The active frontal band is forecast to spread heavy rain into Bay of Plenty and Gisborne today.
The alert states that in addition to widespread rain there is a risk of thunderstorms embedded in the rainband, producing localised downpours with rainfall rates reaching 25-40mm/hr.
Rainfall of this intensity can cause flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips.
Driving conditions will also be hazardous with surface flooding and poor visibility in heavy rain.
The alert warns people to be on the lookout for threatening weather conditions and be alert for possible severe thunderstorm warnings.