New Jersey in the summer? Hope your barracks has air conditioning.
Typical enough East Coast weather. Not going to be as muggy or humid as states further South, but there will be times. Expect average daytime highs to be in the 80s or 90s fahrenheit, with occasional forays into the hundreds.
You will probably be rained on, though more often than not the rain, though heavy, will be over fairly quick.
There are worse places to spend your June. I'm going to the desert.
Well, sortof. The bit that most Americans see, the bit near New York. The Southern parts of the Garden State aren't actually all that horrible. You just need to find an excuse to visit, which is hard. Kindof like Montana.