Tonga or Samoa in Late November??

Hi there,
I'll be travelling to NZ with my husband & 11 month old baby at the end of November. We also want to do a side trip somewhere in the pacific islands for 7-10 days. Weather-wise it doesn't exactly look like the ideal time of year to go, but just wanted to check how wet it gets in either Tonga or Samoa around then? Suggestions for any other destinations easily accessed from NZ are also welcomed!!
FYI we live in Northern Australia so 30+ degree heat and humidity aren't a huge issue for us (or the baby). We mainly wanted to make sure that we weren't going to be stuck inside somewhere due to downpours the whole time!
As for the destination, we are looking for great beaches (swimming / relaxing/ snorkelling etc), somewhere relaxed and friendly, and with scope for cultural experiences and getting out and exploring. We dont mind hiring a car to get around either.
We are open to either Fale type or mid-range accomodation (or a mix of both)... guess it depends on what would be most comfortable for the baby given the weather at that time of year.
Thanks in advance for your help!

If you are into full culture immersion, the outer islands of both would be great...away from Apia or Nuku.

In Samoa, we really enjoyed Savaii, manono, and Apolima islands. For Tonga, any outer islands of Vavau would be comparable.

It all boils down to logistics and how much you want to spend.I like the Idea of flying over to Samoa and renting a car for upolo-savaii then stay a few days in manono island while parking the car at the ferry port. Then get invited by relatives of locals from apolima. Head back to apia and catch a flight to american samoa (pago pago) and check that place out. If there is still $$$ leftover...fly over to ufa island for more local vibe.

It is Ofu Island. The other word would not be polite in Samoan at all ;-)

Talofa and thanks wksamoa. That was a typo. my bad :)
Manuia!