I would agree that in June the route would be in better shape, but that if you are flying in from out of town, the weather could crap out on you. If you choose June, make it early June, not late June. You can count on the weather being bad from mid June through the first week of July. From the second week of July, you can count on the weather being good, or if it is not, its only a matter of waiting a day or two before it is.