Good morning,

A potent ocean storm will pass southeast of Nantucket Friday night and Saturday morning. This will bring strong to damaging winds to Cape Cod and the Islands.  Accumulating snowfall is anticipated across Cape Cod and the Islands. Minor coastal flooding expected for this area as well.

Please see the details below for more information. Attached are graphics depicting the highest wind gusts, highest wave heights, and expected snowfall amounts.

What has changed: 
  • Snowfall amounts increased across southern Rhode Island, south coastal Massachusetts, Cape Cod and the Islands 
  • Wind speeds increased across coastal areas and the ocean 
  • Minor coastal flooding expected
  • Watches upgraded to Warnings - see the headlines section below 
Headlines and Where: 
  • Winter Weather Advisory and High Wind Warning for Barnstable, Dukes and Nantucket counties Friday evening into Saturday morning
  • Coastal Flood Advisory for Barnstable, Dukes, Nantucket and eastern Plymouth counties Saturday morning
  • Wind Advisory for Block Island, Eastern Essex, Southern and Eastern Plymouth counties Friday evening through Saturday morning
  • Storm and Gale Warnings in effect for the ocean waters Friday Evening into Saturday
What: 
  • Northeast winds of 30 to 40 mph with gusts of 50 to 65 mph
    • Highest gusts expected where the high wind warning is in effect
  • Minor coastal flooding expected
  • Snowfall totals of 2-4 inches across Cape Cod, 3-6 inches across Martha's Vineyard and Nantucket with the highest amounts expected across Nantucket
When: 
  • Highest winds are expected Friday night into Saturday morning
  • Highest wave heights are expected Saturday morning
  • Any rain becomes snow Friday evening and tapers off Saturday morning
    • Heaviest snowfall roughly between midnight and 6 AM
  • Coastal flooding expected between 6-11 AM Saturday
Impacts: 
  • Tree limbs and power lines may be blown down that could cause damage along with power outages across Cape Cod and the Islands. 
  • Reduced visibility and slippery travel across Cape Cod and the Islands. 
  • Minor coastal flooding and splash over near the time of high tide Saturday morning
Confidence:
  • Highest in strong winds and waves
    • May have a brief period where there are hurricane force gusts (74 mph) across Nantucket 
  • Low to moderate confidence in snowfall amounts 
    • Amounts may be increased further if the storm shifts a bit closer to the coast
    • Amounts may be decreased if the storm shifts further offshore
  • Moderate confidence in coastal flooding
Expect another updated briefing no later than 5 PM Friday.

Thanks,
Meteorologists Bill Leatham and Frank Nocera 

If you have any questions or would like more information, don't hesitate to contact us via this email address, on NWSChat, or at the following:

National Weather Service Boston/Norton, MA

46 Commerce Way
Norton, MA 02766
508.622.3280
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