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Pacific Storm and Surf Forecast
Updated: December 18, 2009 10:14 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   

Weaker Local Swell Pattern for a Few Days
Dateline Region Looking Stronger Longterm


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 Friday (12/18) North and Central California was getting leftovers from Swell #6 at a t foot or so overhead on the sets and pretty clean early. Southern California was getting the same energy from Swell #6 with waves shoulder to head high and pretty clean on the sets up north pushing 1 ft overhead down south and real clean. Hawaii's North Shore was getting more sideband northern semi-swell with waves head high or so and blown out with Kona's in effect. 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 a little pulse of local gale swell pushing in on Saturday at 3 ft overhead and real westerly fading out on Sunday with new swell from another similar gale only strong pushing in Sunday night and fading Monday sunrise from double overhead. Longer period dateline swell expected in on Tuesday (12/22) at 3 ft overhead. Southern California to see some west swell on Saturday at chest to shoulder high fading from waist high on Sunday. New swell expected in on Monday at shoulder to head high and real west fading Tuesday with new longer periods well building underneath and peaking on  on Wednesday at waist to chest high.  The North Shore of Hawaii is to see more north angled sideband windswell on Saturday at 1-2 ft overhead and possibly cleaning up holding into early Sunday.  Monday more westerly dateline swell arrives at 1-2 ft overhead with larger longer period swell from the dateline right behind for later Wednesday (12/23).  The East Shore is to have no easterly windswell. The South Shore is in hibernation for the winter.

Longterm the Madden Julian Oscillation (MJO) has resurged in the Active Phase, and that is becoming evident on the models.  Besides string on two local gale forecast tracking from just north of Hawaii up towards Oregon on Thurs-Sat (12/19) a gale is forecast pushing to the dateline Sun/Mon (12/21) with up to 36 ft seas targeting the area mid-way between Hawaii and the US mainland, followed by a strong storm pushing from the Kurils to the dateline Tues/Wed (12/23) with up to 44 ft seas aimed the same way, and yet another behind that.  Of course this is all just projected storm, but they have been on the charts for a while now.  Looks like a pretty good run of longer period modest.cgius sized surf for the US West Coast and significant class swell possibly for the Islands. 


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

North Pacific

On Friday (12/18) the North Pacific jetstream has flowing hard off Japan to the dateline, at 190 kts, dipping into a weak trough that was pushing over Hawaii, before lifting and .cgiitting while pushing into Washington and south of Baja respectively. Very limited support for gale development was occurring in the trough north of Hawaii lifting up into British Columbia. Over the next 72 hrs this pattern is to hold but with the jet bumping up to 200 kts and inching further eastward with the trough hanging on if not getting better defined over Hawaii, but energy from the West Pacific is not yet to be dropping into that trough. Clearly the MJO had reactivated. Beyond 72 hours thing are to ramp up with  a trough forming on the leading edge of the powerful jet pushing over the dateline, with winds still at 200-210 kts on Monday and holding into early Wednesday.  Good support for gale if not storm development. The trough on the leading edge of the core jet energy is to just inch further east.  The trough to wash out a bit on Wednesday while winds hold solid over the dateline while digging further south to 32N, then energy level are to fade some, though still at 140 kts over the vast majority of the North Pacific with that .cgiit point holding just off California on Friday.  Decent support for gale development.

At the surface on Friday (12/18) a weak gale was circulating just northeast of Hawaii with up to 40 kts northeast winds aimed back at the Islands, and weak high pressure nestled in the .cgiit jet stream aloft 300 nmiles off Southern CA. This gale was lifting northeast generating nearly 25 ft seas at 32N 152W providing sideband energy aimed towards Hawaii. Also a storm was at the intersection of the dateline and the Aleutians generating a decent sized area of 55 kt west winds at 49N 178E aimed right down the 304 degree path to NCal producing seas of 42 ft at the same location. This system was at it's peak and expected to move into the Bering Sea with in 12 hours with all fetch fading out.  Swell from it is expected to up into the Pacific Northwest and reaching Central CA starting early Tuesday (12/22) at 5 AM with period 18 secs peaking mid-day with swell possibly to 5.5 ft @ 17 secs (9 ft faces).  Swell Direction: 305-305 degrees. Minimal sideband swell possibly to push to Hawaii too. Previously a weak gale had formed 1300 nmiles west of Northern CA on Wed (12/16) generating 23 ft seas at 37N 150W in the evening moving rapidly to the northeast with 25 ft seas at 43N 142W Thurs AM (12/17). Modest 13 sec period swell is expected for Central CA Saturday (12/19) sunrise at 6 ft @ 13 secs (8 ft faces) from 277-285 degrees. 

Over the next 72 hours the gale northeast of Hawaii is to be lifting northeast pushing into Oregon and Washington on Sunday (12/20) but not before generating  35-40 kts west winds late Friday (12/18) and theoretically 30 ft seas at 33N 143 on the 261 degree great circle path to NCal, with residual 35 kts fetch and 25 ft seas at 35N 140W on Saturday AM (12/19) aimed up the 261 degree great circle path to NCal.  If this occurs some degree of 16 sec period swell could arriving in NCal on Sunday evening (12/20) at sunset and starting to peak near 1 AM Monday with pure swell 7.8 ft @ 14 secs  (10 ft faces). Sideband swell for Hawaii too starting sunset Saturday (12/19) at 7 ft @ 11-12 secs (8 ft faces) from 360 degrees.

Also a broad co.cgiex low pressure pool is to start setting up west of the the dateline Saturday (12/19) with a fetch of 45 kt west-northwest winds building way to the south at 38N 165E and getting traction on the oceans surface.  by Sunday AM (12/20)  45 kt west winds forecast at 37N 173E with 35 ft seas at the same locale. in the evening 40 kt west winds to push east to 36N 175W producing seas of 36 ft at 36N 178W targeting midway between Hawaii (312 degrees) and NCal (286 degrees) but favoring the Islands by a good margin.  This system to rapidly deteriorate after that. Possible swell pushing into Hawaii starting at sunset Tues (12/22) peaking near 1 AM Wed with swell to 8.6 ft @ 17 secs  (14-15 ft Hawaiian at top spots) from 312 degrees (assuming the models are correct).            


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


California Nearshore Forecast
On Friday (12/18) light wind and clear skies were in control of California waters.  That is to hold into Sunday, as a broad but generally weak low pressure system lifting northeast off the coast, with a weak front from it possibly reaching south from Cape Mendocino Sunday Am to the SF Bay area in the late evening and Monterey Bay by Monday AM (12/20). Light precipitation to continue north of that point into the late evening, then clearing into Tuesday AM (12/21) with high pressure and a little north winds at 15 kts pushing south to Pt Conception. But by Wednesday light high pressure is to again set up light winds and perhaps some offshore while a broad North Pacific weather system looks to be bearing down on the area. As of right now weak high pressure supported by a .cgiit jetstream aloft is to barely hold it off, with light winds and no precipitation forecast through Christmas (12/25). 

The MJO has moved back into a weak active state. No support for tropical activity is expected for the next 1-2 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 storm is forecast forming off Norther Japan on Tuesday AM (12/22) with winds building to 55 kts,  and seas to 42 ft in the evening, then fading some Wednesday AM with winds down to 45 kts and seas 43 ft at 38N 175E again on that southerly path favoring Hawaii.  In the evening 45 kt fetch is to hold on the dateline with seas still 42 ft at 36N 178W.  Thursday AM (12/24) 45 kt fetch is to rebuild at 41N 175W with a solid area of 37 ft seas at down at 35N 168W. fetch to be fading from 40 kts in the evening with seas heading down.  Possible larger moderate period swell for Hawaii by the weekend with a very west angled swell for the US West Coast  beyond. 

And yet another small system is to possible set up behind that. Clearly the rejuvenation of the MJO (Active Phase) is to have having a favorable impact. 


MJO/ENSO Update (reference): As of Friday (12/18) the Madden Julian Oscillation (MJO) had moved back into the Active Phase with the SOI into negative territory. The ENSO (El Nino Southern Oscillation) index was well negative with the Daily SOI at -28.60. The 30 day average was down to -9.73 while the 90 average was down to -9.04. Nice. 

Wind anomalies at the 850 mb level (approx 5000 ft up) as defined by models indicating westerly anomalies had redeveloped from Indonesia east over the dateline to a point south of Hawaii, exactly in line with where all storm activity is expected the next few days. This area is about peaked out and is expected to slowly fade on the dateline through 12/27, then with remnants drifting east into the east equatorial Pacific into Jan 1. Support for storm formation expected in this region though these timeframes. A very weak version of the Inactive Phase is forming in the Indian Ocean and expected to seep east to New Guinea through Jan 6, likely starting to suppress storm formation at that time.   

Sea Surface Temp anomaly data (12/17) indicated that warmer than normal waters were 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 most solid warm anomaly signature present over and just west of the Galapagos Islands. It is expected that water temps will continue to increase yet more over the coming weeks as this Kelvin Wave (see below) continues impacting the coast there. This is classic El Nino.  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 most 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 12/17 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 is fueling an increase in the warm water surface pool as it continues impacting the coast there.  This pool is expected to continue 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 was the development of a new pocket of warm water on the dateline 3 deg C above normal starting on 12/10.  As of 12/17 it continued to slowly grow in areal coverage and is easing east, currently at about 168W. This looks like the start of a new small Kelvin Wave. 

Over the Equatorial Pacific anomalous surface winds started to move from the west to the east on 11/28 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 and continued 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 solid through 12/15, with fully blowing west winds reaching to the dateline and anomalies to 170W. This WWB started fading by 12/17 but was still present pushing to 175E with neutral (normal) winds east of there.  This configuration is likely helping to feed the a newly developing Kelvin Wave under the dateline (see above), which would be great to help fuel development of El Nino.  If anything, subsurface water temps are expected to increase as the WWB continues pushing warm water into the depths on the dateline, feeding the developing Kelvin Wave there. And 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. So at this time two Kelvin Waves are in the pipe. Impressive.

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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