G'day mate! Well done!
I am in "your neck of the woods" and plants usually begin flowering around early/mid February and are usually finished around end of March/early April.
Being White Widow I would expect it to be finishing around late March, so temps shouldn't be a problem and as long as she is still getting a good amount of sun, everything should be sweet! I have had them outdoors through to early May, no problems, but they do go purple. Frost is the only worry, but that won't come until June/July, so no worries there. If she has really dense flowers and if heavy rain is forecast, a beach umbrella tied to a ladder can serve as a good "anti mould" device.
Hope this helps,..... Organoman.