There’s a large, talented contingent of PNW boats entered in this year’s Pacific Cup Race from the SF Bay area to Hawaii. Three of the boats, Alternate Reality, Gusto and Zipper, started a couple days ago. Several more were starting midday today, including Poke and Destroy, Shearwater and Zaff. I’ll give them a day to get out on the racecourse proper, then do an update. In the meantime, Bruce Hedrick has provided a weather outlook for a race that promises to be anything but simple. -KH
Kurt and I were wondering about how to deal with the plethora of questions that you have sent in so we decided I should provide an overview specific to this year’s event. I will try to get you some insight into what will surely be a very challenging event.
We love the Pacific Cup for a couple of very specific reasons. 1. It’s the shortest race to Hawaii. 2. You end up in Kaneohe Bay, a way better place than Maui or Honolulu. 3. They stagger the start so you start at the same point in the ebb out of San Francisco Bay and you only beat for a very short time (about 45 minutes in a “normal” year) before you start reaching for the Mai-tai’s. 4. They have a great pre-race prep program conducted by veterans. 5. The pre-race and post race parties are absolutely the best. 6. For boats from the Pacific NW, you usually break everything on the delivery south to SF so the first couple of days of the race are “We’ve been there and broken that.”
Since they instituted the staggered start, things have gotten more interesting and I think, for the most part, it has made the race more interesting. Over time it has shown that sometimes you roll the dice about the staggered start and sometimes the dice roll you. This year will be no different as the first starters on Monday left in probably more northwesterly than they wanted, 20-25 with higher gusts. They started with breeze, and are continuing to enjoy reaching in a solid 15-20 knots of North-Northwesterly. The folks that will be starting today will be starting in much less wind and it will continue to recede in front of them. The Thursday and Friday starters are going to be well and truly hosed as a low-pressure system over central California will move offshore and sit right over the big big boats. All the while the early starters will be cranking right along towards the Islands.
According to the tracker there are two very distinct camps with some very respected veterans going very different ways. The problem these folks are trying to solve will start to show up show up tomorrow in the form of an upper level low-pressure system that will set up shop right over the rhumbline. This will create a very large patch of light air and woe be the boats that get caught in that. This is where the navigators will earn their money as they decide to go over the top of this light air death trap or sail underneath it.
Let’s start with the basics. Whatever race you do to Hawaii, you always have to deal with the Pacific High which is the dominant weather feature of the North Pacific in the summer months. There is no wind in the center of the high so we always try to avoid that. The general rule of thumb is always try to keep 4MB of pressure between you and the center of the high to avoid becoming becalmed. Look at the Surface Analysis for July 11th. The high is centered at about 42N, 143W and is not particularly strong at 1035MB. It is also not round so between those two features, shape and center pressure, it is not going to be very stable and will be susceptible to being pushed around by the low pressure systems you see over central California and the North Pacific. We would really like to see the Pacific High be round with a center pressure around 1040MB. You would also like to sail the shortest possible distance, the great circle route which usually takes you way too close to the Pacific High and light air. The key is how you balance the extra distance sailed with how much wind you’ll have, always a challenge.
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The other key feature to watch is the distance between the isobars around the high. The closer they are together, the more wind you will have in that area. Note off the Oregon coast how tight the isobars are and the word Gale! Note also that the spacing between the 1016MB line and the 1020MB line and the 1028 and 1024Mb line is greater than the spacing between the 1020 and 1024MB lines. This will mean more wind between 1020 and 1024MB lines. At least for today.
Now go to the 12 July surface forecast chart and you’ll see that 1008MB low pressure system is moving slowly offshore right over SF Bay. This will bring light air and from the wrong direction, we are not supposed to beat to Hawaii and gentlemen only sail downwind. The gap between the 1016 and 1020MB and 1020 and 1024MB has increased meaning less wind in this area while the gap between 1024 and 1028MB has decreased which should more wind on the north side of the course. The surface forecast chart for 13 July is even more depressing for the late starters as the low has weakened from 1008MB to 1014MB and expanded in area meaning light and variable wind as the racers try to get away from the coast. First person to 130W wins. The Pacific High is also being pushed around by the fronts coming off of the two low pressure systems to the north and northwest of the 1035MB center of the high. The other interesting feature of the high are the two weaker lobes, one to the north and one to the west. Eventually the 1035 high will absorb these two lobes and the high try’s to get back to being round. Note also the gap in the isobars over the race course, less wind in the south, more wind in the north.
The surface forecast chart for 15 July will bring smiles to everyone on the course. The gap between the isobars is almost identical and when that happens the wind is basically the same over the course and those who sail the shortest possible distance will be the victors.
The sailors who handle the transition the best from today to the 15th will be the overall winners and right now I think it will be some one from the first group that started and that sailed the north course. Just my guess.
As always, if you have questions or comments, fire away. This is going to be a fun one to watch. I’ll update on Friday.
Bruce has raced and cruised the Pacific Northwest his entire life. He earned a Bachelor’s of Science from the University of Washington in Biological Oceanography and learned meteorology “to keep from getting kicked around on the race course.” Bruce spent nearly two decades as Associate Publisher for Northwest Yachting Magazine, retiring in mid-2015, and was the chairman of the board of trustees for the Northwest Marine Trade Association in 2014. (photo of Bruce driving Playstation is a bit dated, but cool)