If you are sailing to Hawaii from the PNW you have to go South with maybe a little West to avoid running into the high. If you get too far west between the PNW and SoCal you may be doing a lot of motoring. When I did the trip, the high was quite far north so was able to rhumb line it from SF to Hilo. Quite often you have to go south from SF to get around the bottom of the high. If memory serves me right, the high moves south in the summer and is a pretty constant phenomenon. In the winter it moves north and is quite often non existant because of the train of Low Pressure waves going across the N Pacific. Still would head
south in the winter even if you had fair winds for a rhumb line passage
to get to warmer weather and avoid the lows.
Tropical storms that head
west almost always stay between 10-20N and are easy to dodge. Just keep in close contact with the weather and don't go below 15N till there is a clear path to the Islands. Did that on the passage
to the Marquesas
in July before there was really good tracking of the tropical depressions generated in the Gulf of Panama
. Had a go/no go line that we wouldn't cross if there was a chance of any weather heading west. On the sail to Hawaii. you cross the line with a lot more distance to get out of the danger
zone if you are sailing direct to the islands. If there is weather, all you have to do is head West instead of SW till the storm passes and then reach south to the islands.
The Tropical storms that track to the West typically build in strength over the first half of there vacation cruise
to the Islands often reaching Cat 3 strength. At about midpoint they get into cooler water
and have higher level windshere and begin to dissipate. By the time they get here they are downgraded usually downgraded to a tropical depression with winds not a whole lot stronger than the trades. The waters around Hawaii aren't all that warm. I know you West Coasters think they are bath tub temp but to a tropical low, they aren't warm enough to keep building into significant weather. There is always the exception however like Iniki that hung out south of the Islands in warmer water
building to a Cat 3 storm before it turned due North and wiped out Kauai
. Several of the lows last summer maintained Cat 1 status almost to the islands with one making a direct hit on the East Side of the Big Island. Another passed just to the North while still a tropical storm. Last year was an anomaly and even with that, the three ocean races got to Hawaii without much drama. One cruiser did sail too far south too soon and got beaten up. I would not want to make the passage from Panama
to Hawaii after June and before November, however.