After a quiet few days the North Pacific Storm Track just yelled "Game On!" and now the latest forecasts are lining up a solid NW swell for the West Coast later this week, and into the upcoming weekend. Unfortunately, we are going to have a wait a couple of days before the storm forms and a couple more before the swell actually starts to arrive…For detailed worldwide surf forecasts go to www.magicseaweed.com
The storm is pretty easy to see on the various charts…Check out the Magicseaweed wave-height chart…lets see if you can guess what storm I am talking about…oh the giant red blob about to eat Vancouver? Yeah that might be it.
Like I said this storm looks pretty solid…forecasted central pressure is set to be around 944-millibars which is a pretty deep low-pressure (considering that the "average" pressure is around 1010-mb), and the key areas of fetch will have winds in the 40-50 knot range as well as some stronger gusts. The wave model above even makes it look sort of angry…like it is about to slap the West Coast right upside the head.
This storm is another one of these systems that is getting a boost in energy/intensity from extra-tropical moisture that has pushed into the higher latitudes. These pockets of warm/moist air can hold a lot more "latent heat energy" than the colder air-masses you find further north, so as they drift northward into the cooler high-latitudes they start to cool off as well. The colder they get the less heat-energy they can contain and the excess power is shed out into the atmosphere in some pretty dramatic forms of wind and precipitation. The faster these extra-tropical pockets cool the more intense the energy release…like in this case…we have not one but two areas of tropical moisture going extra-tropical. One is over by Japan and the other is drifting NNE of the Hawaiian Islands….
…both of these warmer low-pressures are squirting around the ridge of high-pressure that has repositioned itself across the Western NPAC…and it seems like the movement of the high is what is actually driving these pockets northward.
Eventually the warm stuff runs into a colder frontal system and the rapid intensification occurs…most of the nastiness starts off up in the Bering Sea, but as the second warm-low moves into position it draws the more intense storm down into the Gulf of Alaska…
The results are pretty insane…50 knot winds and nearly 35-40' seas…an incredible amount of energy being thrown around. Here is a better look at that storm on the sea-level-pressure chart (focused on the Gulf of Alaska)…
Okay that is enough weather-nerdness for this post…lets get on to the good stuff…the surf.
I am expecting a solid NW swell from this storm…unfortunately for Southern California the system is just a little too far to the North to send large surf south of Point Conception. SoCal will get waves…but just a small amount compared to spots further north. Hawaii will also miss out on this one…most of the storm's swell generation takes place "past" the islands…so any swell it would get would be coming back against the grain of the storm track and would be much smaller than it could have been if the storm was in a better position.
Northern and Central California are going to be the best areas on this swell…breaks further north (in the Pacific NW States) may see more energy but the weather looks a bit spotty…the California spots look like they will come through cleaner.
Nor/Cen California will actually see a run of playful WNW-NW swell (285-310) for the next few days, that is holding over from a swell that peaked this weekend. It won't be huge for the next few days but the exposed areas can expect some consistent shoulder-head high surf at the average spots and overhead sets at the better-exposed beach breaks.
The new big WNW-NW swell (285-320) will start to arrive late in the day on Friday Nov 6th and will peak on Saturday Nov 7th before fading out into early next week. At this point it looks like a solid 14-17' of deepwater swell will push through on Saturday…with swell periods in the 15-17 second range. That much energy in deepwater is going to crank out some sizeable breaking waves as it starts to hit the coast…average NW facing spots will see easy double-triple overhead sizes with some bigger bombs mixing in. The standout deepwater breaks, like Mavericks, will be bigger…likely hitting the 15-18' face range on the average sets with some 20-25' faces coming through on the big sets…maybe they will run the Mavs contest on this one (good thing they pushed the waiting period up a bit).
Southern California's forecast compared to Norcal's is a bit of a letdown…but we will still get some waves from this one. We can expect mostly small leftovers for the next few days (and some lovely morning tide-swamp at times)…not totally flat but we aren't going to have much break the chest-shoulder high range.
By the weekend the new NW energy (290-300+) will start to arrive. We can expect new long-period energy to arrive throughout the day on Saturday and then peak overnight into Sunday. Since we have a lot of shadowing from Point Conception and the Channel Islands I am expecting the average WNW-NW facing spots to hold around chest-shoulder high…the top NW facing spots, mostly through San Diego, Ventura, and parts of the South Bay, will be more consistently in the shoulder-head high range and will likely see some head high+ sets on the lower tides. The swell will be on the way down by Monday, but more storm activity out the back will likely set up some more waves for next week.
By Adam Wright
Check back on Friday…I will have the latest details on this swell in my next update. For more forecasting treats, check out Adam's blog at www.socalsurf.com