Answer:
Deep Creek Lake, in Western Maryland, is located in the middle of the Appalachians, and as a result, has a marked continental climate, with very clear four seasons, with hot summers, and cold winters.
Baltimore is located in the center of Maryland, relatively close to the ocean, but inland enough to also have some continental influences. In general, the climate of Baltimore is in the transition between subtropical and temperate.
Ocean City in Maryland, is in front of the Ocean, and at the lowest elevation of the three. For this reason, it has the mildest climate among the three, because the ocean has a moderating effect. This means warmer winters, and milder summers.