A severe weather watch for heavy rain in Tauranga and the Bay of Plenty was this morning upgraded to a warning.
Bay of Plenty Civil Defence issued a statement saying a short period of intense heavy rain was expected early Tuesday morning.
In the six hours from about 2am to 8am Tuesday, expect 50mm to 80mm to accumulate. Peak intensities of 20mm to 30mm per hour are possible with thunderstorms.
A low pressure system over the Tasman Sea is expected to slowly approach New Zealand during Monday and move across the country on Tuesday, Metservice said.
Periods of rain in a very humid northerly flow ahead of the low are expected across northern and western parts of New Zealand.
The watch is for the possibility rainfall accumulations could reach warning thresholds in the Bay of Plenty from this evening.
People are advised to keep up to date with forecasts in case the watch is upgraded to a warning.