Muskmelon are usually available in early August through early September. They are only available for about a month and do not ripen until late summer, but they are worth the wait.
Some people refer to muskmelon as cantaloupe but they are essentially the same fruit.
Melons can be one of the harder fruits to select because you do not know what is inside. If you want a melon to eat the same day, select one with a yellow rind. If you are waiting to cut it for a couple of days, select one that is a little green. Melons will ripen on the counter.