I've always thought it would be early February. The bases and staging will be complete. The UN will have its chance to speak. The cool weather will still be there.
And it will be at least a couple of weeks after we're completely ready, which will drive the Iraqis nuts and shooting at every bird or bug that enters their airspace.
My calendar says Jan 27 is the beginning of Last Quarter Moon and New Moon occurs on Groundhog Day, Feb. 2, 2003.