How Weather Affects Ferry Operations and Cancellations

Wind is the primary factor in ferry cancellations. Operators monitor both sustained wind speed and gusts when making decisions. A steady 20 mph wind might be manageable, but gusts to 35 mph can make docking unsafe.

Different vessels handle wind differently:

• High-speed catamarans are most sensitive, often suspending service at 25-30 mph winds
• Traditional car ferries can operate in higher winds, sometimes up to 40+ mph
• Smaller passenger ferries fall somewhere in between

This is why on the same route, you might see high-speed service canceled while traditional ferry service continues. When checking if the ferry is running, consider which vessel type you're booked on.

A 25 mph southwest wind affects a ferry differently than a 25 mph northeast wind. Direction determines:

• Wave height and period: Wind blowing across open water builds larger waves
• Docking safety: Wind pushing against the dock complicates berthing
• Route exposure: Some directions create crosswinds that are harder to navigate

For example, routes crossing open water like Nantucket Sound are particularly affected by southwest winds, which have a long fetch across the Atlantic. Protected routes through harbors may be more affected by northeast winds during nor'easters.

Not all ferry routes are created equal. Several factors determine how weather-sensitive a particular crossing is:

• Crossing distance: Longer routes spend more time in open water
• Water depth: Shallow water creates steeper, choppier waves
• Protection: Routes through sounds vs. open ocean face different conditions
• Harbor exposure: Some ports are more protected from certain wind directions

This explains why the Hyannis to Nantucket route (26 miles across Nantucket Sound) experiences more weather cancellations than the Woods Hole to Vineyard Haven route (7 miles across Vineyard Sound). The longer crossing has more exposure to deteriorating conditions.

Is the Ferry Running? combines current weather forecasts with historical sailing data to estimate cancellation likelihood. Our system:

• Analyzes years of sailing outcomes across different weather conditions
• Weights factors like wind speed, gusts, and direction for each route
• Accounts for vessel type differences and seasonal patterns
• Updates predictions as weather forecasts change

This approach is designed to scale across hundreds of ports and operators—the same methodology that works for Cape Cod ferries applies to ferry routes anywhere in the world.