CHATHAM -- Preparations are underway ahead of an unusual early-season coastal storm that's expected to bring high winds, coastal flooding and possible power outages to the region over the next few days.

The National Weather Service has posted a high wind warning, coastal flood watch and high surf advisory effective Friday; 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 officials are urging people to finish storm preparations by Friday afternoon, before the onset of rain. 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 say now is the time to secure or bring in outdoor furniture, trash bins, and other loose items. Charge phones and devices before the storm, and have flashlights and supplies ready in case the power goes out. 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. 

Heavy rain from the storm is likely to prompt state officials to enact a statewide, temporary closure of all shellfish harvesting starting Saturday, officials say.

Orleans town officials are recommending that outdoor events planned for this weekend be canceled or postponed.