High pressure settling over Long Island is expected to have a calming effect on winds and seas Friday, the National Weather Service said in its marine forecast.
An approaching cold front Saturday night increases southerly flow and small craft advisory conditions for most waters are possible, the service's Upton office said.
The front is likely to generate ocean waves near 5 feet and wind gusts up to 25 knots for most waters. The front crosses waters Sunday with a "strengthening northeast flow behind it."
On the ocean Friday, variable winds at 10 knots or less become south to southeast, with seas 3 to 4 feet.
On Friday night, the wind shifts to south to southwest at 5 to 10 knots and seas remains in the 3 to 4 feet range, with areas of fog bringing visibility down to 1 nautical mile or less.
On Saturday south winds of 10 to 15 knots become 10 to 20 knots with seas building to 3 to 5 feet.
Friday's inland weather forecast for Nassau and Suffolk counties is for clear, sunny skies with temperatures in some areas, especially the North Shore, reaching close to 80 degrees.