The Sound Side Swims On

Chatham swims on two oceans and retires them one at a time, the cold Atlantic side turning to walking weather by September while the sound and harbor beaches, shallow, sheltered, and warmed all summer across the flats, hold genuinely swimmable water through September and, in the kind years, into October, which makes the elbow one of New England's last swims standing. The series that chases warm water down the calendar in these pages logs one of its latest northern dates here, at the bend of the Cape, where the water refuses to read the calendar.

The geography does the holding, the sound-side shallows south of town banking the summer's heat over pale sand, the harbor beaches inside the bars adding shelter to warmth, and the tide doing its part, the incoming water arriving pre-warmed off the sun-heated flats so that the connoisseur swims the flood, mid-afternoon, when the day's heat and the tide's agree. The September water runs the mid-to-upper sixties in most years, warmer than June's, per the banked-heat arithmetic this series keeps proving, and the beaches themselves run at the shoulder-week emptiness the month guarantees.

The late swims pair with the elbow's September program per its own piece in these pages, the fleet's fall landings, the band's last concerts, the striper dawn on the bars, and the seals, it should be said, keep to the ocean side and the sharks with them, which the purple-flag system and plain sense sort without drama on the swimming beaches inside. The rinse-and-chowder sequence closes the ritual correctly.

Swim the sound side daily through any September stay, favoring the afternoon flood, and log the trip's last swim per the series' tradition, warm shallows, empty sand, the lighthouse working early behind you. Defend the date at dinner all winter. The Cape's summer officially ends on Labor Day, per the traffic report, and unofficially ends whenever the elbow's water finally says so, which is weeks later, and the swimmers who know simply stay in.