In summer the South Fork enjoys the fairest weather. Sun and blue skies give way to spectacular sunsets, and cool evenings call for light sweaters and jackets. You are not alone in knowing this, for the stretch from Memorial to Labor days is high season. But the ocean water doesn't really get warm enough for swimming -- except for the hardiest souls -- until July.
The shoulder season months, May and September, are also a lovely time to visit, when the weather is chilly but sunny, and the locals come out from hiding. Always call ahead off-season: many hotels close during this period, and the bulk of restaurants and stores close for at least a month in winter.
As a rule temperatures are a bit cooler out east than in Manhattan.
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