Windsurfing, surfing, Maui, The Gorge, and random rants.

Saturday, October 30, 2010

Big Surf Boys and Girls Get Yer Engines Ready

I mentioned and showed a weather model in my last post that predicted a large storm was forecast to spin up in the North Pacific. And now that prediction has come to pass. Here's the actual weather map for today...

Note this giant storm has the name "hurricane force".  A very unimaginative name that.  How come all the tropical hurricanes get nice easy to remember name, like "Earl", while these giant northern pacific storms that produce bigger surf, have hurricane force winds, and impact a greater area get squat?  I mean look at the size of that storm!  The pressure gradient lines (or wind contours if you prefer) circle this gyre from the interior of Kamchatka to the coast of British Columbia, while the northern fetch brushes the north slope of Alaska (about the arctic circle) and the southern edge is near 35 deg.

So let's try to estimate the total square miles of this storm's weather influence.  It appears to cover about 60 deg of longitude and 35 deg of latitude.  There is about 69 miles per degree of latitude, which means this storm is 2415 miles "tall".  Miles per degrees of longitude vary depending on whether you near the equator (60 miles) or the poles (0!).  Which makes this an inexact science, so I'm only going to use the height as the diameter (assuming a near circular storm) and give it the old circle area formula of pi*r^2.  I plugged this into my handy calculator (the radius is rounded to 1200) and got 4,523,893.42 square miles.  Lets just call that 4.5 million square miles of the earth's surface over which this unnamed storm is causing the winds to veer.  Now to put that in perspective, the entire continental US  is only 3.5 million square miles.  So this storm we don't even bother to name is almost 30% bigger then the entire US.  Imagine a storm centered on the US that covers it entirely, form coast to coast and from Mexico to Canada.  I'd bet we'd give it a name then! (and probably something like "The MF!").

Now I believe we should correct this injustice and give this storm a name. Considering it's largeness, I thought the name "Big Mama Jama" (assuming we use a female name) would be appropriate.  So BMJ is in the process of stirring up some rather large waves.  This is what our friend Pat Caldwell of the NWS has to say about it.

Hurricane-force winds are expected near the center, to 75 knots. The brunt of this modelled swell is aimed at targets NE of Hawaii. Over a wider area severe gale to storm-force winds are modelled to stretch from near Kamchatka to well east of the dateline, covering a fetch over 1000 nm long. Models show a long duration to the fetch. These aspects are the essential ingredients for creating exceptionally high long period swell. The nose of gales with seas to 30 feet is expected to reach to 1000 nm of Hawaii by late Sunday. Proximity of high seas is one of the important sources for winter-caliber surf in Hawaii. More explicit expectations can be provided after the pattern unfolds and estimates of surface level winds and seas are available. In any regards, consistency among models and model runs over the past 72 hours give credence to this event.

The local surf is expected to ramp up rapidly around sundown on Monday from 320-350 degrees. The episode is expected to peak mid day on Tuesday in the extra-large to marginally giant category, meaning significant breakers on outer reefs.

And here's the estimated wave height tables...



I highlighted the day of interest, which will be Tuesday.  We stopped by the Quattro shop and saw Keith Teboul getting a tow in board ready for action.  It's entirely possible that Jaws will be firing.  Whatever happens I plan to be there with my camera.  I haven't see Jaws yet in person and I'm looking forward to that if it does indeed happen.  Last year we left just a few days before the first giant surf day and the first possible Jaws day of the season (as I mentioned here).  This time I plan to be there.

And now a  few more random things.  We've had some fun days windsurfing both Lowers and Uppers recently, with a small to moderate swell at times kicking up head high waves.  Perfect for practicing those bottom turns and off the lips!  However the influence of BMJ is about to be felt (even here a mere 20 degrees from the equator) and the trades winds are predicted to go into hiding for several days, possibly until Wednesday.  So big day Tuesday (or whatever we will call it, maybe BMJ Tuesday) is likely to be windless.  Which is fine by me as I'd rather be checking out the big surf action.  Also it looks like the large surf is going to be hanging around for the rest of the week.  Not giant mind you, but plenty big.

The Nelscott Reef big surf contest off the Oregon Coast is on for this Tuesday and BMJ will be throwing them the biggest waves they've ever had.

And it's interesting that this La Nina winter, which is normally expected to have few if any giant surf days, has now sent one our way so early in the season.  The pattern so far seems to be this - a week or so of wind with small to moderate waves, and then a significant swell with perhaps a few days of light wind.  First there was a decent swell at the end of September (and early for the big size), then another one ten days ago, and now this.  Plus we've had pretty consistent wind, with windsurfing on 24 out of 30 possible days so far this month.  La Nina years usually have stronger (and occasionally wetter) trades and so far that part of the pattern is holding true.  Sounds good to me - if this holds we should have a nice combination of waves and wind throughout the winter. Last year there was very little wind between December and February but many (many!) days of large surf.  So hopefully things will be a bit better mixed this year.

Finally (and note this is a work in progress) I put together a page that shows the future weather models.   This is still in "beta" and right now I need to update the internal links manually, but eventually I hope to have this automatically show the next 7 days of weather maps along with the forecast swell heights and direction.  Cheers!

1 comment:

Jeff said...

Big Mama Jama! Love it! LOL

Copyright © 2011 Jamin Jones, All rights reserved.