Denise, have you checked at Weather Underground?
You can check the monthly temps in an easy to view calendar for all the past years. Click the links below and scroll down to the monthly calender view with the graphics. From there, you can go back through the years. I am not sure where you are going in NZ so I used Auckland as my city, you can change that as well.
Auckland April 2008 weather Auckland November 2008 weather
