Hi, Michael!
Walt Disney World's
Extra Magic Hours are offered to Guests of select WDW Resort hotels, enabling them to enjoy some extra time in a park each day during their stay. Each day, you'll find that one park offers a.m. EMH or p.m. EMH; there will be one EMH offered each day.
Keep in mind, too, that
park hours can be adjusted, so keep an eye on park hours as your trip draws closer.
For your trip, Magic Kingdom seems to be closing at 11:00 for the most part. However, there are EMH at MK on Sunday, July 14th, from 11 p.m. to 1 a.m., if you are lucky enough to be there at that time.
Have fun planning your days in WDW, Michael; be sure to send more questions as you think of them, too. We love to help!