"[Today] will be slightly cooler for both cities with high cloud forecast. On Thursday things will cool a little more as a low makes its presence felt with an expected high of 20C. Rain will develop in the morning with heavy showers a possibility, but will clear in the afternoon."
On Friday things are a little better with isolated showers predicted for both cities combined with westerly winds.
"Saturday should see periods of rain, possibly heavy and thundery, and the westerly wind will do a complete turnaround and become northerly," Best said.
"Temperatures of 21C for Rotorua and 24C for Tauranga can be expected.
"Sunday will see showers and little wind."
The online forecast predicts rain with light winds on Monday, showers with light winds on Tuesday and rain with northerlies on Wednesday.
"The forecast up until Sunday has been compiled by a meteorologist, after that is an automatic forecast which is not always accurate," Best said.
Tauranga forecast
Today: High 27C overnight 16C. Fine apart from some morning cloud. Light winds and sea breezes.
Tomorrow: High 25C overnight 17C. Morning and evening cloud, otherwise fine. Westerlies.
Friday: High 24C overnight 16C. A few showers. Westerlies.
Saturday: High 24C overnight 15C. Periods of rain developing. Northwesterlies.
Sunday: High 23C overnight 15C. Showers with little wind.
Monday: High 22C overnight 14C. Rain with light winds.
Tuesday: High 22C overnight 14C. Showers light winds.