* WHAT...Northeast winds 30 to 40 kt with gusts up to 60 kt and seas 21 to 26 feet expected. * WHERE...In Massachusetts coastal waters, Coastal Waters extending out to 25 NM South of Marthas Vineyard and Nantucket. In Rhode Island coastal waters, Coastal Waters from Montauk NY to Marthas Vineyard extending out to 20 NM South of Block Island. In Atlantic coastal waters, Ocean Waters from Marthas Vineyard to Nantucket from 25 to 60 NM and Ocean Waters from Montauk NY to Marthas Vineyard from 25 to 60 NM. * WHEN...From 2 AM Friday to 8 PM EDT Saturday. * IMPACTS...Storm force winds and hazardous seas will capsize or damage vessels and reduce visibility. Mariners should remain in port, alter course, and/or secure the vessel for severe conditions.