It’s generally more expensive to depart on a Monday, if you have to leave on this day you can still search on Cheapflights to find great options that meet your needs.
Due to multiple factors, expect to potentially pay more when booking in December. For low rates, March can be a great choice for travel to Honolulu. Flights to Honolulu from Arcata in March are about $456 on average during March, but can be found for as low as $229.
A simple way to save on the total cost of your ticket is to fly from Arcata to Honolulu in the morning. If you’re flexible enough to do this you can expect to save up to 12% on your trip compared to booking a flight at noon.