MetService meteorologist Ciaran Doolin said today's temperature of 31C would be topped tomorrow with a high of 32C, but then temperatures were going to "drop down considerably".
"Both days are looking pretty fine, with the exception of some high cloud and light winds," Mr Doolin said.
But scattered rain was forecast to develop on Wednesday morning.
The south-easterly winds would pick up over the day, turning to strong gales, and there was an expected high of 23C.
He said the region could expect rain on Thursday and Friday, with a high of just 18C for both days.
Friday would see light southwesterlies winds.
Mr Doolin said a tropical low would be behind the rain and strong winds of Wednesday and Thursday.
Next weekend temperatures were not expected to exceed 19C, with rain and light winds over Wairarapa both Saturday and Sunday.
Mr Doolin said it was too far out to predict the forecast for Waitangi Day.