I know of of one fellow who did the trip in January. He said he had a pleasant sail with only a couple of days of winds in the 30s from Hilo to San Diego
. Since he was on a reach, it just got him to San Diego
faster. Other than that you are taking a big risk. The lows march across the north Pacific
at 4-8 day intervals so your chances of getting hit by serious bad weather
at least 3 times on the passage
are quite good. One good thing is the high tends to move south in the winter so you don't have to go to as high a latitude to get around it. It's still probably going to mean going above 40N, unfortunately. The high also breaks down and weakens and/or disappears entirely during the winter. You could get really wierd wind
condtions like southerlies for most of the trip.
Since you want to go to Mexico
, you might be able to duck under the high. Would be a lot of windward work but at least it would be moderately warm for the whole trip.
If it was me, I'd wait for late spring but if you gotta go, you gotta go. Suggest paying for a professional weather router to tell you when the conditions will be optimal. The fellow I mentioned did just that. Waited for nearly a month in Hilo for the go sign from his weather guy. The call finally came telling him to leave right now and he had as good a sail as is possible.