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Pacific Storm and Surf Forecast
Updated: December 13, 2009 1:12 PM
Buoys: Northern CA - Southern CA - Hawaii - Gulf of Alaska - Pacific Northwest
Buoy Forecast:
Northern CA - Southern CA - Hawaii - Gulf of Alaska - Pacific Northwest
Pacific Links:  Atmospheric Models - Buoy Data - Current Weather - Wave Models
Forecast Archives: Enter Here
A chronology of recent Mavericks Underground forecasts. Once you enter, just click on the HTML file forecast you want to review (e.g. 073199.html equals July 31, 1999). To view the maps that correspond to that forecast date, select the html file labeled 073199 maps.html
Swell Potential Rating = 3.9 - California & 3.5 - Hawaii
Using the 'Winter' Scale
(See Swell Category Table link at bottom of page)
Probability for presence of largest swells in near-shore waters of NCal, SCal or Hawaii.    
Issued for Week of Monday 12/14 thru Sun 12/20
Swell Potential Rating Categories
5 = Good probability for 3 or more days of Significant swell
4 = Good probability for 1-2 days of Significant swell
3 = Good probability for 3 or more days of Intermediate/Advanced swell
2 = Good probability for  1-2 days of
Intermediate/Advanced swell
1 = Good probability for 3 or more days of Impulse or Windswell
0 = Low probability for 1-2 days of Impulse or Windswell   

More Rain for the US West Coast
Steady but Unremarkable Storm Pattern Forecast


New Swell Classification Guidelines (Winter)

Significant: Winter - Swell 8 ft @ 14 secs or greater (11+ ft faces) for 8+ hours (greater than double overhead). Summer - Head high or better.
Advanced: Winter - Swell and period combination capable of generating faces 1.5 times overhead to double overhead (7-10 ft) Summer - Chest to head high.
Intermediate: Winter - Swell and period combination generating faces at head high to 1.5 times overhead (4-7 ft). Summer - Waist to chest high.
Impulse/Windswell: Winter - Swell and period combination generating faces up to head high (1-4 ft) or anything with a period less than 11 secs. Summer - up to waist high swell. Also called 'Background' swell.

On Sunday (12/13) North and Central California was getting locally generated west windswell with south winds and decent size in the nearly double overhead range, but pretty much hacked to death. Southern California was getting the same windswell with waves about thigh to maybe waist high and heavily textured early up north and perhaps a hair cleaner down south. Hawaii's North Shore was getting the tail end of a nice pulse of reinforcing swell from a gale that pushed east to the dateline Tues/Wed with set waves 1-2 ft overhead and clean as a whistle. Beautiful. The East Shore has no surf of interest. The South Shore was asleep for the winter.

The forecast for North and Central CA is for fading windswell at 2 ft overhead on Monday with intermixed dateline swell building about the same size with winds building from the southeast as the next front sets up. That swell to continue Tuesday but getting overrun by south windswell into Wednesday with a new front hitting the area with south winds and rain likely. Southern California to see more west windswell on Monday at waist high or so with thigh high dateline swell intermixed. Tuesday dateline swell is to continue at thigh high turning to pure windswell on Wednesday at the same size. Light winds early. The North Shore of Hawaii is to see a steady stream of generally small but well rideable sideband swell coming from a series of weak low pressure systems tracking fairly fast east over the dateline towards the Gulf of Alaska for the next 5 days or more. Swell mostly 5 ft @ 11-12 sec resulting in surf head high to a little overhead. The East Shore is to have no easterly windswell. The South Shore is in hibernation for the winter.

Longterm the Madden Julian Oscillation (MJO) is fading out of the Active Phase moving towards a dead neutral state later this month. No obvious enhanced support for storm development expected by 12/21. A modest gale was starting to develop in the Central Gulf of Alaska on Sunday (12/13) expected to push east and into the Pacific Northwest on Wednesday with 40 kts winds and generating 35 ft seas,.possibly setting up swell for later in the week for the US West Coast and more very modest sideband swell for the Islands. Another gale to follow right behind on Wed-Thurs with yet another behind that on the weekend, but all tracking hard north into Canada as high pressure tries to get a foothold over California. At the same time a far broader gale is to be trying to organize over the northern dateline for the weekend, though any particular result from it is too early to project. But certainly no stillness is projected for the North Pacific (which is good).


Current marine weather and wave analysis.cgius forecast conditions for the next 72 hours

North Pacific

On Sunday (12/13) the North Pacific jetstream has flowing flat west to east from Japan into Northern Baja on the 35N latitude with one pocket of 150 kts winds north of Hawaii trying to create a bit of a trough there and supportive of gale development down at the surface. Otherwise winds were generally light and no conducive to gale development. Over the next 72 hrs that trough is to not develop much and is expected to push into the PAcific Northwest late Tuesday while the jet almost .cgiits just a few hundred nmiles off Southern CA offering some storm protection from North CA southward. Beyond 72 hours that .cgiit pattern is to hold while more energy builds off Japan reaching to the dateline by Wednesday (12/16) with a new trough starting to dig in north of Hawaii Thurs (12/17) with 170 kt winds feeding into it.  Perhaps a new gale to develop in that area. And by Friday (12/19) up to 200 kt winds are to start building off of Japan pushing 210 kts by Sunday (12/20) and looking to start feeding perhaps a big trough in the East Pacific. Looks like good support for gale development is possible longerterm.

At the surface on Sunday (12/13) a new gale was starting to build in the Central Gulf of Alaska with 40 kt west winds modeled at 42N 160W targeting primarily the US West Coast with sideband energy towards Hawaii. Another low pressure system was developing off Japan bound for the dateline and weak high pressure was trying to set up between Hawaii and Baja but pretty much useless. Over the next 72 hours semi tropical energy that has been migrating east from Japan since Friday (12/11) pushing over the dateline is to start building Sunday PM (12/13) with 40 kts northwest winds at 42N 160W and taking good aimed initially on Hawaii down the 345 degree great circle path but quickly swinging east. By Monday AM (12/14) a solid fetch of 40-45 kt west winds are forecast at 41N 150W pushing right down the 290 degree path to NCal with 30 ft seas forecast at 41N 153W. In the evening up to 45 kt west winds forecast at 41N 151W aimed up the 289 degree path to NCal and mostly bypassing Hawaii. 35 ft seas forecast building at 40N 150W. This system is to hold Tuesday AM (12/15) with 40-45 kt west winds at 40N 145W aimed right up the 285 degree path to NCal with 35 ft seas forecast at 40N 145W. In the evening residual 35 kts winds are to be aimed due east at 40N 140W pushing up the 285 degree path to NCal with 35 ft seas fading at 42N 140W. 40 kt west winds to hold Wednesday AM (12/16) this system is to be pushing into the Pacific Northwest with 28 ft seas 600 nmiles west of Cape Mendocino. Possible decent sized but raw swell is likely to result for the US West Coast with even some size into Southern CA if this comes to pass, with perhaps limited sideband energy for Hawaii (but indistinguishable from already present sideband swell, just bumping the size up a foot or so Tues into Wed 12/16).  

Weak Dateline Gale
A new gale was building just west of the dateline on Tuesday AM (12/8) with winds modeled at 35 kts. That
gale continued east in the evening with 35-40 kts west winds modeled at 37N 170E producing 28 ft seas at 38N 165E then pushed east over the dateline Wednesday (12/9) evening with 35-40 kts west winds at 42N 170W with 23 ft seas at 37N 178W. This fetch was aimed well at Hawaii down the 305-312 degree great circle paths. The gale is to fade some on Thursday (12/10) with 35 kt west winds covering less area but consolidating with 28 ft sea over a tiny area at 44N 171W late. The gale is to dissipate near there on Friday AM with residual 23 ft seas at 43N 164W pushing towards NCal up the 294 degree path and bypassing Hawaii. This system to dissolve after that.  

Swell of 4.5 ft @ 15-16 secs (up to 7.0 ft faces) is expected for NCal by Monday AM (12/14) from 292-295 degrees though that size estimate might be a little optimistic.  


North Pacific Animations: Jetstream - Surface Pressure/Wind - Sea Height - Surf Height


California Nearshore Forecast
On Sunday (12/13) a fading gale low was pushing into North CA at 1004 mbs generating west to southwest winds at 15-20 kts pushing into the Central CA coast. Light rain was still occurring and a solid snow pack was developing in the Sierras. Solid snow has fallen since Friday with most resorts reporting 3 ft of fresh snow pushing base depths to the 60 inch range, which is pretty good for the time of year. And more is forecast today (Sunday) with another system scheduled into the Sierras later Tuesday continuing all day Wednesday, then taking a break. Good in that it will allow the snow to settle some and compact, making for a stable base and allow resorts to get everything in shape so that the next dump (not scheduled yet) will actually be the one to chase. On the coast Monday a short break in the storm action is forecast with south winds starting to ramp up in Central CA ahead of the next front/gale. Then Tuesday and early Wednesday a full south wind event is scheduled from Pt Conception northward with rain in the forecast down to San Louis Obispo. Weak high pressure is to hold on just off Southern CA protecting that region. By Thursday (12/17) light winds and clearing skies are forecast and holding into the weekend, though a large local gale is to moving dangerously close to the coast then. Certainly no lack of precipitation and potential for stormy weather especially for the northern half of the state.

The MJO has moved into a neutral state. No support for tropical activity is expected for the next 3-4 weeks. 

No tropical systems of interest were being monitored. 


South Pacific

At the surface no swell producing fetch was occurring and none is forecast for the next 72 hours.


South Pacific Animations: Jetstream - Surface Pressure/Wind - Sea Height - Surf Height




Marine weather and forecast conditions 3-10 days into the future

North Pacific

Beyond 72 yet another gale is to form right north of Hawaii sweeping northeast with up to 45 kt northwest winds by Thursday AM at 40N 150W targeting mostly the Northern CA down the 290 degree path, but lifting northeast pretty fast and not getting particularly good traction on the oceans surface. Perhaps some seas developing. Yet another gale is to be right behind setting up some 35 kt fetch just barely north of Hawaii late Thursday (12/17) perhaps generating north windswell for the Islands but again lifting fast to the northeast resulting in a broad area of 40 kt northwest winds at 40N 140W on Saturday (12/19), holding into Sunday and perhaps generating swell for the US West Coast.

And yet another gale is forecast trying to develop over the dateline Sunday (12/20) with pockets of 35-40 kt west winds a bit further north than previous systems at 45N 175W and starting to consolidate. Nothing guaranteed but certainly something to watch.      


MJO/ENSO Update (reference): As of Sunday (12/13) the Madden Julian Oscillation (MJO) was fading fast from the Active Phase in the Pacific, and for all practical purposes was gone. The ENSO (El Nino Southern Oscillation) index was up to the positive range with the Daily SOI at 0.31 (27 consecutive negative days previous to 12/9). The 30 day average was up some to -7.33 while the 90 average was up a breath to -7.09.  

Wind anomalies at the 850 mb level (approx 5000 ft up) as defined by models indicating dead neutral winds over the entire equatorial Pacific with no change forecast into Jan 1. The Active Phase is over, but there's no sign of and Inactive Phase behind it, a good thing. This pattern neither helps nor suppresses the development of storm in the North Pacific. But with El Nino in.cgiay, it will likely excerpt a steady but subtle push for the formation of storms.

Sea Surface Temp anomaly data (12/10) indicates that warmer than normal waters are consolidated on the equator from Ecuador and Columbia west to the dateline and even west of there, and starting to rebuild some along the Baja coast, but not much.  A new strong Kelvin Wave (see below) was erupting along the coast and some evidence of it can be seen with a more solid warm anomaly signature present over the Galapagos Islands extending west from there to 2 deg C above normal. It is expected that water temps will increase yet more with the introduction of this a Kelvin Wave (see below).  Overall the warm water signature remains non-exceptional from a historical El Nino perspective, but clearly in the moderate category and building slowly but steadily.  

Below the surface on the equator things continue to look favorable. A steady flow of warmer than normal subsurface water continues tracking from the West Pacific (150 m below the surface) under the dateline and breaking the surface near Central America as it has for months now.  As of 12/13 the Kelvin Wave we've been tracking with a core of 5-6 deg C warmer than normal sub-surface water was impacting the Galapagos and Ecuador coast. This should fuel an increase in the warm water surface pool as it continues impacting the coast there building and eventually tracking back west on the equator driven by trades. This Kelvin Wave first appeared under the dateline on 9/17 and tracked steadily east through 12/1 and was the result of a prolonged persistent westerly surface wind flow that had been in.cgiace west of the dateline from 9/8 and continued into 11/5.  Of additional interest is the development of a new pocket of warm water on the dateline 3 deg C above normal starting on 12/10.  As of 12/13 it continues to slowly grow in areal coverage and is easing east, currently at about 170W. This looks like the start of a new small mini-Kelvin Wave. 

Over the Equatorial Pacific anomalous surface winds started to move from the west to the east extending the whole way from Indonesia to a point south of Hawaii, with fully blowing west winds confirmed in the far West Pacific. This was a new Westerly Wind Burst which started on 11/28 and was very obvious on 11/30 with fully blowing west winds near 165E, and strong. This Westerly Wind Burst (WWB) continued on 12/2 through 12/8 with a most solid area of west winds pushing almost to the dateline. On 12/6 strong west anomalies pushed to 170W and held on 12/8. And on 12/9 the trend continued with fully blowing west winds reaching to the dateline and anomalies to 170W.  Even on 12/13 solid fully blowing west winds continued pushing east to about the dateline. This is likely helping to feed the a new Kelvin Wave under the dateline (see above), which would be great to help fuel development of El Nino. The Kelvin Wave currently hitting Ecuador was formed from a prolonged bout and mult.cgie pulses of westerly winds and westerly anomalies that occurred from 9/8 through 11/2. At one point towards it's end the anomalies reached the whole way from the West Pacific to almost Ecuador. Embedded in that run were Typhoons Dujuan, Choi-Wan, Parma, Melor and Nepartak. All this helped to deepen the surface warm pool in the tropical Eastern Pacific.   Typhoon Nida and Storm #5 was associated with the most recent WWB.

El Nino is expected to affect the global atmospheric weather pattern at least through Spring of next year if not into the middle of summer. All data suggests this will not be a strong El Nino, more likely a moderate one. NOAA's last update (11/5) forecasts the same outcome, though hints at some uncertainty.  In short, all the best models aren't exactly sure how this is going to.cgiay out. Regardless a solid accumulation of warm water in the equatorial East Pacific is evidence in-favor of continued development. As long as there continues to be WWB's (as there obviously is), then warm water will be migrating east, and the warm water pattern will hold if not build, and the atmosphere above it will respond in-kind to the change (towards El Nino). At this point there is no evidence to suggest this El Nino will stall or dissipate. The only remaining question is whether it will hold, or grow. And current data indicates that the warm pool will hold if not slowly build. And historically it is already larger and strong than any other in the past 12 years. 

The current El Nino is gaining strength, with a 2 degree water temp anomaly in the tropical East Pacific the likely outcome. Coverage is pretty solid for this event, but the lack of really high water temp anomalies will likely limit it's strength. Strong El Ninos bring lot's of bad weather to the US West Coast, along with the potential for storm and swell enhancement. A moderate El Nino provides storm and swell enhancement, a gentle but steady push/momentum in-favor of storm development rather than the manic frenzy of a strong El Nino, but without all the weather associated with a strong event. So in many ways a moderate El Nino is more favorable from a surf perspective. As of right now things remain better than anything the Pacific has seen in the past 12 years regarding anomalous sea surface temperatures, besting anything since the big El Nino of 1997. That is very good news.  But the lack of anomalous water temps exceeding 3 degrees and an unremarkable SOI suggests a modest El Nino at best. Still, it should be enough to provide storm enhancement, and a better than average winter surf season for the North Pacific, and still likely better than anything in the past 10 years. Better yet, if it's not too strong (as this event appears to be) perhaps it will not degrade into La Nina the year after (which typically happens after stronger El Ninos), but hold in some mild El Nino like state for several years in a row. This would be an even better outcome.    

See more details in the new  El Nino update.


South Pacific

Beyond 72 hours the models suggest no swell producing fetch is to develop.   

Details to follow...


External Reference Material: El Nino Southern Oscillation (ENSO), Madden Julian Oscillation (MJO), Pacific Decadal Oscillation (PDO), Southern Oscillation Index (SOI), Kelvin Wave

Add a STORMSURF Buoy Forecast to your Google Homepage. Click Here: Add to Google
Then open your Google homepage, hit 'edit' button (top right near graph), and select your location


Local Interest

Interview With Stormsurf:  The crew at worked with Stormsurf on a feature about why surfers should be able to read wave charts themselves. They are firm believers that a little learning can go a long way to help your surfing.  This is a great article to help convince your friends that they can benefit from being able to read the data themsleves rather than just relying on the forecasts of others.  See the full thing here:  Create Your Own Surf Forecast with Stormsurf

Mavericks - Everest of the Sea & Longboard Vineyards: Come late October Sonoma County will not only welcome a new crop of world class wines, but the award winning photography of some of Action Sports best lensmen. “ Mavericks – Everest of the Seas” comes alive again just in time to set the stage for another epic Big Wave Season. Mix two of Northern California's finest institutions – big wave surfing and the wine country – and you have what promises to be an amazing weekend at the Longboard Vineyards Tasting Room in Healdsburg
October 23 – 25.

Relive heroic battles between man and wave as seen through the eyes of the cutting-edge photojournalists who risk life and limb to document the wave's intense man-against-the-sea drama and obsessive lifestyle of Maverick's elite riders. Oded Shakked, a longtime surfer who founded Longboard Vineyards, will be unveiling his latest release, The Peter Mel/Mavericks Cabernet Sauvignon. This signature wine will be blended by not only Shakked but guest vintner, Peter Mel. Mel, one of the most respected names in Big Wave Surfing is known as perhaps the most skillful surfer ever to ride Mavericks. The famed spot off the Half Moon Bay. In October of 1998 he was whipped into to what is now considered the biggest wave ever ridden… Mel along with the featured photographers, surfboard shapers and wine makers will be on hand for the Friday night reception. The reception will begin at 5pm and run until roughly 9pm.

Longboard Vineyard has always had a soft spot for surfers. It's a.cgiace where you can hangout at a redwood-surfboard bar, or sa.cgie one
of its award winning wines while kicking back on a comfortable sofa watching surf movies. For this harvest weekend event Shakked has
enlisted “Mavericks: Everest of the Seas,” the heralded collection of Mavericks surf photography from Frank Quirarte, Doug Acton, Seth
Migdail and Ed Grant.

“Everest of the Seas” first made its debut recently at the Coastal Arts League Gallery in Half Moon Bay, drawing large crowds and an
enthusiastic response. It just finished a one-month highly successful run at San Francisco's world class Museum and Gallery, SFMOMA.“Everyone who sees the exhibit is just blown away,” said Grant, the curator of the Coastal Arts League Gallery. “Both surfers and non-surfers can't help but get caught up in the energy and stoke that surrounds Maverick's, the surfers and photographers who put it on the
line every time they go out there.”

The event also represents a high point in the career of Oded Shakked, who was born in Israel and grew up near a beach just north of Tel
Aviv. Immersed in surfing from the start, he made several trips around Europe's Atlantic coast while discovering, to his delight, that “it
was easier, cheaper and safer to drink good red wine than bottled water.” His twin loves of surfing and wine brought him to California,
where he studied winemaking at UC Davis and became enamored with the pe.cgie, climate and rich soil of Sonoma County. He founded Longboard Vineyards with the motto “Wine, waves and soul,” making it a highly unique fixture in wine country.

The October 23-25 weekend will also feature the sale of surfboards and memorabilia, along with Acton's acclaimed book, “Inside Maverick's.”
Admission is free. Opening reception sponsored by Maverick Events and Longboard Vineyards

The Kelly Slater Project - A fundraiser is scheduled for Aug 29th at the Cocoa Beach Country Club to help raise funds for both the Kelly Slater Project and the Central Florida Animal Reserve. A Casino night is.cgianned including a silent auction and raffle. Sponsors are also needed. Learn more about these projects at :

Rebuild Jeff Clark: Jeff Clark the first pioneer of Mavericks, recently underwent hip resurfacing surgery due to severe pain from deterioration of his hip. Needless to say the procedure is very expensive and his insurance only covers tiny portion of the bill. If you're interested in learning about the procedure or would like to donate to help Jeff out,.cgiease take a look here:

North California Surf Report Works Again: After an extended downtime we finally got the North California Surf Report working again. Thanks for your patience. See it here:

Shark Video: Our friend Curt Myers of Powerlines productions shot this footage of 2 great whites munching on a whale carcass off Devils Slide (south of San Francisco) on Thursday. Kind of interesting to watch. Check it here: (Fixed link)

Wave Model Upgrade Status Report: At this point we believe the installation of the new wave models is complete, with no problems being reported, the server stabilizing and the much requested return of the old style hemispheric Surf Height models now operational (again) and running side-by-side along the new ones. We thank you for your patience and input as we went though this process.  Your feedback helps guide our efforts and ultimately results in a better product for everyone.  Now we're off to start providing better menus to some wave model products most of you probably haven't uncovered yet (site specific graph and text forecasts), updateing the wave model FAQs and then upgrading the Weather Models.  

New Wave Model Facts: Click HERE to read more about the new wave models. Important info.

Stormsurf Wave Models Updated: On Friday (2/6) we installed the latest upgrade to our wavemodels. A year in the works, this upgrade essentially is a total re-write of every wave model product we produce. They now take advantage of the new Version 3 of the Wavewatch wavemodel. This version runs at a much higher resolution, specifically 0.0 X 0.5 degrees for the global grib with local products at 0.1667 X 0.1667 degrees, and it uses the hi-res GFS model for wind speeds. And of even more interest, the model now identifies primary swell and windwave variables. As such we now have new model images which displays this data. Also we've included out special 3D topographic land masks into all models. In all it makes for a radical step forward in wave model technology. We'll be upgrading minor components (FAQ, new menu pages etc) for a few weeks to come, but all the basics are available for your use now. Check it out here:

Story About Stormsurf: The folks at SurfPulse (and specifically author Mike Wallace) have written up a really nice article about Stormsurf, complete with some good pics. Learn about how we came to be and a little of where we are going. Check it out here:

Stormsurf Video: Just for fun - here's a clip about Stormsurf that ran on Bay Area TV a while back. Thought you might enjoy it:

Time Zone Converter By popular demand we've built and easy to use time convert that transposes GMT time to whatever time zone you are located. It's ion left hand column on every page on the site near the link to the swell calculator.

Need Chiropractic Help? Visit our friends at Darrow Chiropractic. Not only will Dr. Darrow fix you up, he might give you some big wave surfing tips too! See more here:

Stormsurf Google Gadget - Want Stormsurf content on your Google Homepage? It's si.cgie and free. If you have Google set as your default Internet E.cgiorer Homepage, just click the link below and a buoy forecast will be added to your Google homepage. Defaults to Half Moon Bay CA. If you want to select a different location, just click on the word 'edit', and a list of alternate available locations appears. Pick the one of your choice. Content updates 4 times daily. A great way to see what waves are coming your way! .xml

Free Stormsurf Stickers - Get your free stickers! - More details Here

Read all the latest news and happenings on our News Page here

Surf Height-Swell Height Correlation Table


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