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PACIFIC SCIENCE, Vol. XXII, April 1968 
Commonly, periods range from 8 to 10 seconds, 
and heights from 10 to 15 ft. In a typical year, 
Kona storm waves may be arriving in the 
Hawaiian Islands during 93% of the time, 
usually during the winter months. 
4. North Pacific Swell. Waves produced by 
storms in the Aleutian area and by mid-latitude 
lows may arrive in the Hawaiian area through- 
out the year, but they are largest and most 
numerous during the period October through 
May. They may approach from the northwest, 
north, or northeast, and typically have periods 
of about 10-15 seconds and heights of 8-14 ft. 
Some of the largest waves reaching the Hawaiian 
Islands are of this type. 
In addition to the above four representative 
