I thought Christmas in July was a southern hemisphere thing. In Australia (have not heard it mentioned much in NZ) it is a chance to have all the traditional hot Christmas foods. Where I lived in the Mountains behind Sydney it is advertised by hotels etc as a weekend and they have roast dinners, plum pudding, roaring log fires, mulled wine. These are not things so popular in the heat of December when seafood and salads and a day at the beach are more likely these days.