Since FI and I live in the north, my family already told me under no circumstances were they coming up when it's cold. So that eliminated half of the year. I also didn't want it to be mega-hot, so we said no to July and August. With FI required to work graduations for his employer in May, May would be a hectic time. When we decided on June, FI suggested we do 6.9.12 because he's a perv ("69"). I liked the numbers because they are multiples of 3 (my favorite number) and the numbers flow to me.