"After a brief warmer spell for most, the second half of the month looks very changeable."
McInnes said Tauranga and Rotorua had told a similar story in October.
"In Tauranga it has been quite a nice October, though that's been marred a bit by the past few days," he said.
"The average temperatures weren't actually too far off. The long-term average is 14C and Tauranga is sitting at 14.3C.
"We did have lower than average rainfall but it's sitting bang on average for the number of wet days we'd expect."
However, McInnes said Rotorua had been drier than average.
"Rotorua temperatures are looking almost exactly on average but there were a number of days we got into the 20s."
He said the maximum temperature in Rotorua in October was 22C. The highest recorded average from 1992 to 2003 in October was 23.4C.
In Tauranga, the highest temperature in October was 23C, compared with a highest recorded average of 23.6C.
"That's not nearing on record but you're reaching temperatures in the upper ranges of what's normally recorded.
"It's been a nice spring in the Bay of Plenty."
McInnes said this weekend would be the "opposite of a stunning weekend".
"The weather we had at the start of October is typical for spring, it's just contrasted by quite benign weather before that and benign weather after that."