Labor Day is a mere memory, and the leaves are getting ready to do their annual red, gold and orange thing, but that doesn't mean it's time to say goodbye to summer just yet.

As beach dwellers have long known, but kept quiet about, September and October are actually two of the nicest months in the year to hit the coast. The water is still warm from the summer sun, but the humidity lifts, making everything crisp and crystalline. The crowds die down, and with school back in session, even the most family-friendly destinations become quiet romantic getaways -- especially midweek. And during the shoulder season, of course, prices drop.

For West Coast beaches, the weather is arguably the nicest of the year. For instance, the average temperature in September in Laguna Beach is exactly the same as it is in August, and drops off by a few degrees in October. Yet it's possible to secure prime hotel rooms (and spa treatments and dinner reservations) with far less notice than you would during the hectic summer months. Surf and Sand is right on the beach, so close that each room is furnished with ear plugs for guests troubled by the sound of waves. You'll need to make reservations at least 30 days in advance in the summer, when each weekend typically sells out. But you've got a good chance of snagging even a weekend reservation for a prime room in the fall with as little as one week's notice.

That's California, the land of sunshine. What about the Northeast, where there's a true autumn? It's definitely cooler than it is during summer, but the beach still can by idyllic if you plan properly. During the heat of summer, you could easily wile away entire days at the beach, swimming in the cool water and warming on the sand. With the season's cooler temps, you'll be warmer in the water, so your sandy sojourns will most likely be shorter.

The trick is to visit a place where there's more to do than simply watch the waves, and for this, Martha's Vineyard can't be beat. Stay close to the action at the Harbor View hotel, whose newly renovated cottages have recently hosted the likes of Jada Pinkett Smith and Rachael Ray. At this resort, bikes are complimentary for guest usage, which is perfect for the more athletically inclined vacation. Throw on your bathing suit beneath your activewear and hit some of the island's many biking and hiking trails. You can bike around the island and, with the help of a couple ferries, you can also hit Chappaquiddick. The sea breezes will keep you cool, but when they inevitably die down, you'll be ready to jump into the ocean for a quick dip. The chef at the Harbor View will provide you with a backpack picnic lunch, or leave it loose and grab a lobster roll and clam chowder at Net Result. (If you have a second lobster roll, consider throwing in a day of kayaking as well.)

Thanks to sparser crowds, you'll find it more pleasant to contemplate the clay cliffs of Aquinnah (previously known as Gay Head), or even to take one of the island's many organized tours. And don't forget to shop the end-of-season sales at Edgartown's many boutiques, or take a trip to Martha's Vineyard Glassworks , where you can stand close enough to the oven to feel the heat as beautiful glass objects are created before your eyes.

As day turns to night, take advantage of being in one of the few places on the East Coast where you can watch the sun sink into the water -- best accomplished at Menemsha Beach. During summer, you'll have to arrive early in the day to secure a prime spot on the beach, not to mention a parking spot, and it's best to call Larsen's Fish Market at least a day ahead to make sure your lobster is steamed and ready to devour, along with the chilled white wine you'll bring with you. But at this time of year, it's safe to call for your lobster just a few hours ahead. Snuggle up and watch the sky turn gold, orange and crimson above the water. It's a preview of the color palette you'll soon see in the trees -- but not just yet.