CHATHAM -- An unusual early season northeaster spread high winds and rain across the region Saturday, but the impact appeared less severe than forecasters had anticipated.

A number of boats broke their moorings and washed up on shore in Chatham and Harwich, the largest a sailboat that ended up on the shore of Stage Harbor. A fishing boat that had beached during the February blizzard and remained on the shore south of Lighthouse Beach was washed south and could be seen getting pounded by the surf in the channel between Morris Island and North Monomoy Island.

"Given the amount of boats in the water, it's remarkably minor," said Chatham Harbormaster Jason Holm. "It could be a lot worse."

It was too early to tell the impact on the outer beach or whether there was significant erosion along the shore, he added.

Wind gusts of 59 miles per hour were reported in Hyannis. The highest gust at the Chatham Fish Pier was 53 miles per hour.  Only a handful of power outages were reported on the Lower Cape. Capewide, Eastham had the highest number of outages at 348 as of 1:30 p.m.

A high wind warning, flood warning and high surf advisory remained posted by the National Weather Service through tonight and Sunday.

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The National Weather Service has posted a high wind warning, coastal flood watch and high surf advisory; forecasters are predicting winds gusting to 60 mph or higher, with coastal flooding and erosion likely on northeast- and east-facing shorelines. Locally, the greatest impacts are expected on Nauset Beach, in Pleasant Bay and Chatham Harbor, though there may be some flooding on Nantucket Sound-facing beaches, depending on the exact storm track.



In addition to causing street flooding, heavy rains could also overwhelm boats' bilge pumps, Chatham Harbormaster Jason Holm warned. He urged boat owners to prepare their vessels for heavy weather, and to remove dinghies along the shoreline. When boats can't be removed from the water, owners should reinforce moorings, anchors, dock lines and fenders, and relocate boats to more protected harbors if possible.

Eversource is warning customers that power outages are possible, since trees remain fully leafed-out, leaving branches vulnerable to wind damage. Local Eversource crews and additional crews from off-Cape are being staged across the Upper, Mid, Lower and Outer Cape, and the utility is preparing for the possibility of a multi-day restoration effort. 

The heaviest winds and rain are expected Saturday, when coastal flooding will be at its worst. The storm will linger Sunday into Monday, with lessening impacts until the weather system fully clears out on Tuesday or Wednesday. The storm could dump as much as five inches of rain on parts of Cape Cod. Officials are encouraging people to plan to stay home Saturday, since travel may be hazardous because of high winds, downed trees, and localized flooding.

Officials advise people to stay away from downed power lines and never drive through flooded roads. Stay off beaches and away from waterfronts during high tides and rough surf.  High surf  began affecting the outer beach earlier this week, and at high tide Friday afternoon, several wash-overs were visible on North Beach Island. Significant erosion was alrelady apparent on the bluff at the southern end of North (Nauset) Beach.

According to the Barnstable County Regional Emergency Planning Committee, regional shelters are not expected to be needed during the storm, though officials will consider opening shelters if localized conditions require them. 

The Mass. Division of Marine Fisheries has enacted a precautionary closure of all shellfish harvesting starting Saturday at dawn. Heavy rainfall can cause pollutants from the shore to temporarily contaminate local waters.

Officials are recommending that outdoor events planned for this weekend be canceled or postponed.