Guide

Are the Waves Bad on Your Cruise Route?

Typical and rough-day wave heights for each stretch of sea, by month, with the water temperature.

No live line for this stretch here: the National Weather Service forecasts these waters only in its offshore forecasts.

Gulf of Alaska crossing in October: waves are typically 8.4 ft (2.6 m).

Rough days (1 in 10)
15.3 ft 4.7 m or more
Water
50°F 10°C

Wave Heights by Month

Typical Rough days (1 in 10) Scale: 0 to 18 ft

Show as a table
Month Typical Rough days (1 in 10) Water
January 11.2 ft (3.4 m) 17.7 ft (5.4 m) 41°F (5°C)
February 10.5 ft (3.2 m) 17.7 ft (5.4 m) 40°F (5°C)
March 8.4 ft (2.6 m) 14.7 ft (4.5 m) 40°F (4°C)
April 7.1 ft (2.2 m) 13.2 ft (4.0 m) 41°F (5°C)
May 5.9 ft (1.8 m) 9.9 ft (3.0 m) 43°F (6°C)
June 4.8 ft (1.5 m) 9.2 ft (2.8 m) 48°F (9°C)
July 4.4 ft (1.3 m) 7.3 ft (2.2 m) 54°F (12°C)
August 5.3 ft (1.6 m) 9.3 ft (2.8 m) 57°F (14°C)
September 7.2 ft (2.2 m) 12.7 ft (3.9 m) 55°F (13°C)
October 8.4 ft (2.6 m) 15.3 ft (4.7 m) 50°F (10°C)
November 10.5 ft (3.2 m) 17.6 ft (5.4 m) 45°F (7°C)
December 10.9 ft (3.3 m) 17.4 ft (5.3 m) 42°F (6°C)

Source: NDBC buoy 46001, 2008 to 2025.

Buoy wave heights and water temperatures: NOAA National Data Buoy Center.

Wave height is significant wave height: the average of the highest third of waves. Rough days (1 in 10) is the 90th percentile: 1 reading in 10 for the month is at or above it.