"There's not really one place holidaymakers will want to be," Ms Flynn said.
"The good news is most areas will improve over the weekend."
WeatherWatch was expecting a low pressure system to bring rain to many parts of the North Island across the weekend.
A weak southerly change on Tuesday would bring more showers but otherwise conditions were expected to stay the same next week.
Main centres forecast
Whangarei: Today: Showers easing this evening and southeasterlies. High 25C. Monday: Cloudy periods, a few showers and easterlies. High 24C.
Auckland: Today: Showers clearing this afternoon. High 27C. Monday: Morning cloud but mainly fine. High 26C.
Tauranga: Today: Fine. Southeasterlies turn northeast then die out. High 27C. Monday: Long fine spells. Easterly breezes. High 24C.
Hamilton: Today: Chance of shower this afternoon. High 28C. Monday: Mainly fine with chance of afternoon shower. High 27C.
Wellington: Today: Fine with not much wind. High 24C. Monday: Fine with light winds and afternoon southerlies. High 24C.
Christchurch: Today: Cloudy and drizzle overnight. High 20C. Monday: Drizzle in the morning and cloud breaking up. High 21C.
Dunedin: Fine spells with northeast winds. High 22C. Monday: Fine apart from morning and evening cloud. Afternoon northeasterlies. High 20C.