Update 1 - Heavy Rain Warning now starts from 6 AM monday
The updated forecast from the MetService has the Warning period extended by 2 hours now starting from 6:00am Monday to 2:00am Tuesday, otherwise the details remain the same.
Heavy Rain Warning for Gisborne
Ranges
Issued 08:17pm Sunday 21 Apr
2019
Area: The ranges of eastern Bay of Plenty
and the Gisborne ranges. Valid: 20 hours from 6:00 am Monday
to 2:00 am Tuesday. Heavy northerly rain. Expect 80 to 120mm
of rain to accumulate during this time, especially about and
east of the Waioeka Gorge. Peak intensities of 15 to
25mm/hr, possibly more, and thunderstorms
possible.