The airports include: Oakland, San Diego International Airport, Mineta San Jose International Airport, and the Sacramento International Airport.
Southwest Airlines announced plans last week to fly to four cities in Hawaii, which include Honolulu (island of Oahu), Kahului (Maui), Lihue (Kauai) and Kona (Hawaii's "Big Island").
RELATED: Southwest announces four Hawaii destinations
The flights are expected to start late this year or early in 2019. The discount airline didn't reveal specific dates, but promised more details soon.
Southwest is still waiting certification to fly its Boeing 737s on the long overwater routes between Hawaii and the U.S. Mainland.
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In the past, Southwest has said that it plans to fly most of its routes from California and charge less for ticket prices compared to other carriers.
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