🟠 Severe Urgent Action Required

Storm Warning

Coastal waters from Provincetown MA to Chatham MA to Nantucket MA out 20 nm; Coastal Waters extending out to 25 nm South of Marthas Vineyard and Nantucket

Storm Warning issued December 18 at 12:27AM EST until December 19 at 3:00PM EST by NWS Boston/Norton MA

Alert Description

* WHAT...South winds 30 to 35 kt with gusts up to 50 kt and seas 8 to 13 feet expected. * WHERE...Coastal waters from Provincetown MA to Chatham MA to Nantucket MA out 20 nm and Coastal Waters extending out to 25 nm South of Marthas Vineyard and Nantucket. * WHEN...From 9 AM to 3 PM EST Friday. * IMPACTS...Storm force winds and hazardous seas will capsize or damage vessels and reduce visibility.

Safety Instructions

Mariners should remain in port, alter course, and/or secure the vessel for severe conditions.

Time Information

Effective

Dec 19, 2025, 2:00 PM

Expires

Dec 18, 2025, 9:00 PM

Issued

Dec 18, 2025, 5:27 AM

Alert Details

Severity

Severe

Urgency

Immediate

Certainty

Observed

Issued By

NWS Boston/Norton MA

National Weather Service