Weather is very similar -- hot, humnid, even at night, and usually some intermittent thunderstorms daily although you can get somewhat more rain in June than July. Crowds from mid to late June are also similar to mid-July-- very large although nowhere near as bad as Easter time, Christmas or July 4 week. Better rates for some resorts exist in July as the deluxes other than AKL and WL change from regular" season to "value" season usually about July 5 and discounts in the past seem to be have been more available for July than June. What you do get in July that you don't get in June is a large contingent of South American tour groups as mentioned above (much of July is mid-winter break time for those countries). Park hours are generally the same.