Metservice now says there is a possibility of up to 100 millimetres of rain falling in a short burst tomorrow over the Coromandel Peninsula and the Kaimai Ranges.
The advice is not a formal severe weather warning at this stage but rather advice about a possibility that could cause problems.
Earlier, Metservice had advised of a general potential for heavy rain to become more widespread tomorrow over the Coromandel and Kaimais.
“This new advisory of the potential for up to 100 millimetres in a short time means there is now potential for a big volume of rain falling quite quickly,” said duty emergency management officer Dave Lovatt.
“We repeat our advice for the public to watch out for rising river levels, slips and other disruptions to transport links. Stock should be moved to higher ground if necessary,”
Currently, river levels in the eastern part of the Waikato region are already high following reasonably steady rain there over the past three weeks.
Any more heavy rain falling over the weekend on the Coromandel and the Kaimais will place further significant pressure on these river systems.
Mr Lovatt said regional council staff would monitor river levels closely and provide advice as necessary.
Rainfall and river level data is available at www.waikatoregion.govt.nz.