Glassey also said there was a "significant cold outbreak" moving over the country later in the week.
MetService forecasted a high temperature of 15C and an overnight minimum of 5 - 6C in Tauranga for Thursday.
In Rotorua, a high of 13C and overnight lows of 1 - 2C were forecast for Thursday and Friday.
"But because [the] Bay of Plenty is largely sheltered from the south, south-west direction, they're actually in quite a good spot."
MetService meteorologist Ciaran Doolin said the region experienced widespread rainfall over the weekend as a low-pressure system with associated fronts affected the North Island.
An inland station in northwestern Bay of Plenty recorded 124.2mm in the 36 hours from midnight Friday to midday Sunday.
In the same period, Rotorua Airport recorded 92.9 mm and Tauranga and Whakatāne recorded 68.5mm and 68.4mm respectively, he said.
Yesterday, State Highway 33 was closed from Paengaroa to Okere Falls due to several slips and fallen debris.
Contractors worked to clear debris and provide traffic control, a Waka Kotahi New Zealand Transport Agency statement said. It advised drivers to avoid the area or use SH36.
SH2 was also closed at the Kaikokopu Bridge at Pukehina for a period of time yesterday because of a 100-metre stretch of flooding.
While the flooding was not deep, police requested the closure because of safety, a Waka Kotahi New Zealand Transport Agency media statement said.
It reopened under stop/go traffic management, but the agency said if the water rose again, it would have to close the road once more.
State Highway 2 Waimana Gorge was also closed yesterday morning after multiple slips between Station Rd, Tanetua and Woodlands Rd in Ōpōtiki. The road has since reopened.
As of 4pm yesterday, State Highway 35 remained closed between Maraenui and Omaio due to a large number of slips. Waka Kotahi contractors were working tirelessly to clear multiple slips. The detour was via State Highway 2 Waioeka Gorge.
Greerton Marist Rugby Club administrator Lajanne Smith said on Sunday its rugby fields had flooded.
"Every time we get rain, it always gets flooded."
Smith said it would take "a good week of good weather" for the flooding to clear.
The forecast in Tauranga
Today: Showers, with thunderstorms possible in the afternoon and evening. Northwesterlies changing southerly in the evening.
Tomorrow: Often cloudy. A shower or two, mainly in the evening. Southeasterlies dying out in the morning, then light winds.
Wednesday: Showers, clearing in the morning to partly cloudy weather. Westerlies.
Thursday: Fine with southerlies.
Friday: Fine. Westerlies.
Saturday: Partly cloudy with light winds.
Sunday: Partly cloudy. Light winds.
The forecast in Rotorua
Today: Showers, with thunderstorms possible in the afternoon and evening. Northwesterlies changing southerly in the evening.
Tomorrow: Morning cloud then fine breaks. Southeasterlies dying out in the morning, then light winds.
Wednesday: Mostly cloudy with a few showers, clearing to fine in the evening. Westerlies.
Thursday: Fine. Southerlies.
Friday: Fine with southerlies.
Saturday: Partly cloudy with light winds.
Sunday: Showers. Light winds.
Source: Metservice