Alaska is the state that is due north of Hawaii. Hawaii is about 2,300 miles off California's west coast and is also the southernmost state. By plane, it takes about three hours to reach Hawaii from San Francisco, per Reference.com.
Alaska is the state that is farthest north as well as east and west. The reason Alaska is recognized as both the easternmost and westernmost state is that part of the Aleutian islands cross over 180 degrees longitude into the Eastern Hemisphere, past Greenwich and the Prime Meridian. For practical intent, Maine is considered the easternmost state while Alaska still takes northernmost and westernmost and Hawaii takes southernmost status.