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Pacific Storm and Surf Forecast
Updated: Monday, November 21, 2016 2:35 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
4.3 - California & 2.0 - 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 11/21 thru Sun 11/27

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   

Another Gulf Gale Developing
Mult.cgie Solid Systems to Follow

On Monday, November 21, 2016 :

  • Buoy 187 (Pauwela): Seas were 8.5 ft @ 8.3 secs with swell 5.7 ft @ 8.5 secs from 55 degrees.
  • Buoy 46025 (Catalina RDG): Seas were 5.9 ft @ 13.7 secs with swell 3.9 ft @ 12.9 secs from 272 degrees. Wind northwest 16-20 kts. Water temperature 64.2 degs. At Ventura swell was 3.3 ft @ 12.6 secs. At Santa Monica swell was 3.4 ft @ 10.4 secs from 262 degrees. At Camp Pendleton swell was 2.2 ft @ 13.1 secs from 249 degrees. Southward at Pt Loma swell was 4.3 ft @ 13.4 secs from 277 degrees.
  • Buoy 46012 (Half Moon Bay)/029 (Pt Reyes): Seas were 10.2 ft @ 12.5 secs with swell 7.4 ft @ 11.8 secs from 282 degrees. Wind northwest 10-14 kts at the buoy. Water temp 59.0 degs.

    46006, 46059, Hi-res Buoys

Swell Classification Guidelines

Significant: Winter - Swell 8 ft @ 14 secs or greater (11+ ft faces) for 8+ hours (greater than double overhead).
- 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/Utility Class: Winter - Swell and period combination generating faces at head high to 1.5 times overhead (4-7 ft).
- 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.
- up to waist high swell. Also called 'Background' swell.

Surf Heights for Hawaii should be consider 'Hawaiian Scale' if period exceeds 14 secs.

Current Conditions
On Monday (11/21) in North and Central CA Gulf swell was fading with waves about 8 ft on the face and clean early but with less power than the day before. At Santa Cruz the same swell was wrapping in producing surf at head high and clean and lined up and good looking. In Southern California up north surf was chest high and clean but with some warble in the water early. Down in North Orange Co sets waves were 1-2 ft overhead and pushing solidly from the north with a fair amount of north warble on it early. Hawaii's North Shore was background north windswell at chest to head high and clean and fun looking at top spots. The South Shore was flat and clean. The East Shore was getting a east windswell and north wrap around swell with waves head high and chopped from east trades.

See QuikCASTs for the 5 day surf overview or read below for the detailed view.

Meteorological Overview
Residual swell from a gale that tracked from the Western Gulf to a point off North CA Wed-Sat (11/19) with 25-28 ft seas was still hitting California, but down considerably from its peak on Sunday (11/20). A gale was tracking east from the North Dateline region through the Gulf of Alaska Sat-Tues (11/22) with 26 ft seas. Another gale is to develop just off Kamchatka later Mon (11/21) with up to 40 ft seas but quickly fading while track east over the North Dateline region and gone on Wed (11/23). Yet another gale is to develop in the Eastern Gulf on Wed-Thurs (11/24) with seas in the 22-24 ft range. After that a short pause then a storm is to develop in the Eastern Gulf on Sun-Mon (11/28) with up to 43 ft seas while yet another gale develops in the Northwestern Gulf with 28 ft seas and yet another of Japan with 38 ft seas. So an active pattern remains forecast, at least for now.  

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

North Pacific

On Monday AM (11/21) the jetstream was tracking east off Northern Japan with winds to 150 kts in one main pocket starting to form a weak trough over Southern Kamchatka then fading while ridging gently northeast over the intersection of the dateline and the Aleutian Islands before falling southeast over the Gulf of Alaska with winds rebuilding to 120 kts forming a trough and offering some support for gale development there. From there the jet was tracking into North CA at 100 kts. Over the next 72 hours the Gulf trough is to track southeast and weaken pushing over the Oregon-CA border on Wed AM (11/23) no longer supporting gale development. But the developing trough over Kamchatka is to ease east and just barely south and clear of the Western Aleutians into Tues (11/22) with winds holding at 150 kts offering some limited support for gale development there before impacting the Aleutians on the dateline. But by Wed (11/23) that pocket of wind energy is to rebuild while stating to fall into the Gulf of Alaska with winds nearly 170 kts carving out a new trough tracking quickly east into Thurs AM (11/24) offering support for gale development. And that trough is to persist in the Eastern Gulf into Friday (11/25) with the same effect. Beyond 72 hours starting Sat (11/26) the jet is to remain well consolidated streaming off Japan at 150 kts then gently ridging northeast with the peak of the ridge di.cgiaced to the Western Gulf with the Gulf trough pushing over and into the Pacific Northwest. By Sun (11/27) two more pockets of wind are to be building, one off Japan at 180 kts and another in the Northwestern Gulf at 170 kts, creating yet one more trough in the Eastern Gulf Sun-Mon (11/28) mostly likely being mostly a weather producer for the Pacific Northwest down into North CA. By Mon (11/28) it is to be moving onshore, but the pocket of wind energy off Japan is to be creating a new trough just east of the dateline being fed by 130 kt winds offering support for gale development, with another trough developing over the Southern Kurils. Maybe the storm pattern is to start shifting west some.

Surface Analysis
On Monday (11/21) swell from a gale through the Gulf of Alaska was fading in California. Beyond a series of gales are forecast to stack up behind tracking mainly through the Gulf of Alaska. The first of this series is developing now (see Another Gulf Gale below).

Over the next 72 hours a gale is to develop off Kamchatka Mon PM (11/21) with 45 kt west winds over a solid area building seas to 35 ft at 51N 165E targeting mainly the Central Aleutians with sideband energy for Hawaii (325 degs HI, shadowed for NCal). Tues AM (11/22) fetch to hold at 45 kts from the west and easing east with 40 ft seas at (51.5N 171E 328 degs HI) aimed like before. It's to track east-northeast in the evening at 35-40 kts moving over the Central Aleutians with 34 ft seas at 51N 178E mostly shadowed by the Aleutians but with some energy radiating towards Hawaii (334 degs) and NCal (308 degs). It is to track over the Aleutians on Wed (11/23) getting sheared and obscured by land and loosing identity. Maybe some swell for mainly Hawaii with luck.

Another gale is forecast developing in the Gulf on Tues PM (11/22) with winds building from 35 kt from the west and tracking east. On Wed AM (11/23) winds to build to 40+ kt from the west over the Eastern Gulf aimed well at the Pacific Northwest and seas building fast from 24 ft at 47N 144W (308 degs NCal). Fetch is to hold while falling southeast in the evening at 40 kts off South Oregon with 24 ft seas at 43N 139W (296 degs NCal), 600 nmiles west of Oregon. A secondary fetch to move over the same area Thurs AM (11/24) at 30-35 kts from the west off Cape Mendocino with seas fading from 20-22 ft at 40N 130W targeting Cape Mendocino (292 degs NCal). Raw swell possible for North and Central CA.


Another Gulf Gale
On Sat PM (11/19) a small gale developed over the Northern Dateline tracking east-southeast with 35 kt northwest winds generating a tiny area of 25 ft seas at 47N 179E (330 degs HI). On Sun AM (11/20) a broader area of 35-40 kt northwest winds were organizing while pushing east with seas 24 ft over a modest area at 47N 169W (342 degs HI). Fetch built more in the evening to 40 kts over a modest area with seas to 28 ft at 48N 166W (347 degs HI, 302 degs NCal). Fetch faded Mon AM (11/21) from 30-35 kts over a broad area in the Central Gulf with seas holding at 26 ft at 45N 156W (296 degs NCal). Fetch is to hold while easing east in the evening at 35 kts from the northwest with seas 25 ft over a solid area at 45N 150W (297 degs NCal). On Tues AM (11/22) fetch is to be tracking east at 35 kts from the northwest with seas 26 ft at 47N 143W (308 degs NCal). Residuals fading from 30 kts off Oregon in the evening with 25 ft seas at 45N 139W (308 degs NCal). Larger raw swell possible for the Pacific Northwest with solid more north angled energy reaching down to Central CA (above 295 degs for SF).

North CA: Rough data suggest swell arrival on Wed PM (11/23) building to 9.5 ft @ 14 secs (13 ft) peaking overnight. Swell fading on Thanksgiving Day (Thurs 11/24) from 9.8 ft @ 14-15 secs early (14.5 ft). Swell Direction: 296-301 degrees     


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


Tropical Update
No tropical systems of interest are being monitored.

California Nearshore Forecast
On Monday AM (11/21) a light northwest wind flow was in control early with weak high pressure trying to get a toe in the door and is to build to 15 kts later in the day. Clearing skies were trying to take control. A foot of snow had accumulated at higher elevations of Tahoe. Tues (11/22) a new front is to be pushing into the North Coast with south winds 20 kts mainly north of San Francisco and light north winds forecast at 10-15 kts or so for Pt Conception. Moderate rain late afternoon for North CA reaching San Francisco well after dark. Wednesday (11/23) a high pressure ridge is to be pushing down the Central Coast. Rain to migrate down to Monterey Bay early and dissipate there. 6-8 inches of snow for Tahoe during the day clearing late. Thursday (11/24) another front is to stall over Cape Mendocino with south winds there 20 kts turning to calm from Pt Arena south to Big Sur with northwest winds 15 kts for Pt Conception. Rain north of Pt Arena. Friday (11/25) the front is to reach south to Santa Cruz with south winds 15 kts and rain reaching there well after dark. A little more snow for Tahoe late. Saturday high pressure and northwest winds 15-20 kts to take control of the entire CA coast. Rain fading over the North Coast with light snow for Tahoe through the day. Sun (11/27) high pressure is to still have a toe in the door with northwest winds 15 kts south of San Francisco and up to 25 kt over Pt Conception with south winds 20 kts and a new front over Cape Mendocino pushing south to Pt Reyes late. Rain pushing south to San Francisco late. Monday (11/28) northwest winds to be 20 kts down the coast to Pt Conception with rain moving south to Pt Conception late and possible heavy snow for Tahoe.



South Pacific

Surface Analysis  
No swell of interest was in the water and no swell producing fetch of interest was occurring.

Over the next 72 hours no swell producing fetch of interest is forecast.


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




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

North Pacific

A storm is forecast to develop in the Northern Gulf on Sat PM (11/26) with 55 kt northwest winds and seas on the increase from 29 ft at 50N 156W falling southeast. On Sun AM (11/27) a large fetch of 50-55 kt northwest winds are to be in.cgiay aimed at the Pacific Northwest with 41 ft seas tracking east at 50N 145W. 50 kt northwest winds to hold in the evening with seas 43 ft at 48N 138W. The gale is to fade Mon AM (11/28) with fetch dropping southeast from 40 kts with seas 37 ft at 46.5N 134W. In the evening fetch is to be fading from 35 kt from the northwest just off Oregon with 32 ft seas at 42N 131W. Large raw north swell is possible if one is to believe the models. This outcome is highly unlikely.

Yet one more storm is forecast developing just east of the Dateline on Mon AM (11/28) with winds building from 35 kts over a moderate area lifting northeast and then to 50 kts from the northwest in the evening with seas building from 28 ft up at 47N 169W targeting the Pacific Northwest.

And yet another storm is forecast developing off Japan on Mon (11/28) with 45-50 kt west winds and seas building from 38 ft at 40N 153E. All this is not believable and was not on the charts the previous run of the model. Still it's something to monitor.

South Pacific

Beyond 72 hours no swell producing fetch of interest is forecast.

More details to follow...


SOI Steady - Oct PDO Values Rising Some

The Madden Julian Oscillation is a periodic weather cycle that tracks east along the equator circumnavigating the globe. It is characterized in it's Inactive Phase by enhanced trade winds and dry weather over the part of the equatorial Pacific it is in control of, and in it's Active Phase by slack if not an outright reversal of trade winds and enhanced precipitation. The oscillation occurs in roughly 20-30 day cycles (Inactive for 20-30 days, then Active for 20-30 days) over any single location on the.cgianet, though most noticeable in the Pacific. During the Active Phase in the Pacific the MJO tends to support the formation of stronger and longer lasting gales resulting in enhanced potential for the formation of swell producing storms. Prolonged and consecutive Active MJO Phases help support the formation of El Nino. During the Inactive Phase the jet stream tends to .cgiit resulting in high pressure and less potential for swell producing storm development. The paragraphs below analyze the state of the MJO in the Pacific and provide forecasts for MJO activity (which directly relate to the potential for swell production).

Overview: The 2014-2016 El Nino is all but gone except for remnants in the upper atmosphere. La Nina is developing but weaker than expected.

KWGA/Equatorial Surface Wind Analysis & Short-term Forecast:
Analysis (TAO Buoys): As of Sunday (11/20) east winds were over the entire equatorial Pacific continuing but weaker over the Kelvin Wave Generation Area. The KWGA is on the equator from 135E-170W and 5 degs north and south. Anomalies were weak westerly over the equatorial East Pacific and neutral over the far west KWGA. Any easterly anomalies are solely attributable to La Nina and are modulated by the MJO.
1 Week Forecast (GFS Model): Weak east anomalies were modeled over the dateline/East KWGA today and are forecast to build over the dateline for the coming week (through 11/28). The first real easterly wind burst from this La Nina started on 9/23 and is to continue holding for the foreseeable future. We are thinking it will not end anytime soon but rather will just pulse, stronger at times, then weaker, attributable to La Nina, and modulated by the MJO.

Kelvin Wave Generation Area wind monitoring model: West and East

Longer Range MJO/WWB Projections:  
OLR Models: As of 11/20 the last remnants of the Active Phase of the MJO was barely hanging over the dateline with the Inactive Phase building moderately over the far West Pacific. The Statistic model projects the Inactive Phase of the MJO building over the dateline a week out, then weakening and almost gone 2 weeks out. The dynamic model depicts the same thing but with the Inactive Phase of the MJO weakening and not making it to the dateline. 
Phase Diagrams 2 week forecast (ECMF and GEFS): (11/21) The ECMF model indicates the Active Phase of the MJO was weak over the Western Indian Ocean. It is forecast to collapse in 24 hours and remain indiscernible for the next 2 weeks. The GEFS model depicts the same thing but maybe a little stronger.  
40 day Upper Level Model: (11/21) This model depicts the Inactive Phase of the MJO was tracking over the East Pacific moving into Central America on 11/26. A weak Active Phase is to build in the West Pacific on 11/27 tracking east to Central America on 12/19. A weak Inactive Phase to follow in the West Pacific starting 12/18 pushing east to the Central Pacific on 12/31.
CFS Model - 3 month (850 mb wind): (11/21) This model depicts a weak Inactive MJO signal starting to reach into the KWGA from the west with weak east anomalies in.cgiay. It is to holding through 11/29 with mostly neutral wind anomalies in core of the KWGA. Then weak west anomalies are to develop 12/1 with a weak Active Phase developing 12/8-12/15 with weak west anomalies for the KWGA. An Inactive Phase to follow 12/18-12/31 but weak west anomalies are to hold. A stronger Active Phase to follow 12/31-1/16 with west anomalies building some. Overall the MJO signal is projected to be very weak and this pattern is to hold as we move deeper into Fall. We suspect La Nina is having the effect of dampening the MJO, and producing weak east anomalies in the KWGA but not producing an outright Inactive Phase of the MJO. Likewise the MJO is serving to dampen the effects of La Nina when in the Active Phase.

CFSv2 3 month forecast for 850 mb winds, MJO, Rossby etc

Subsurface Waters Temps
TAO Array: (11/21) Actual temperatures remain stratified with warm water in the West Pacific at 30+ degs C (reaching east to 161E) and the 28 deg isotherm line reaching to 170W and steep, suggesting a hard break between warm water in the west and cool water in the east at depth. This is expected with La Nina developing. Anomaly wise, warm anomalies at +1-2 degs rule from the West Pacific to 175W with a tongue of warmer water at depth reaching east to 150W. This is an upgrade and sort of looks like a Kelvin Wave, but it is not. Neutral to weak negative anomalies are east of there to Ecuador at not more than -1.0 degs. This large cool pocket appears to be warming some. The hi-res GODAS animation posted 11/14 still depicts a pocket of cooler water -2-3 degs below normal in the East Pacific at mainly 140W down 125 meters, but it is warmer and less expansive than months past. La Nina is in control of the ocean at depth, but not strongly so.

Surface Water Temps: The more warm water in the equatorial East Pacific means more storm production in the North Pacific during winter months (roughly speaking). Cold water in that area has a dampening effect. Regardless of what the atmospheric models and surface winds suggest, actual water temperatures are a ground-truth indicator of what is occurring in the ocean. All data is from blended infrared and microwave sensors.
Satellite Imagery
Hi-res Nino1.2 & 3.4: (11/20) The latest images (1.2 3.4) indicate a thin cool pool of water along the immediate coast of Peru reaching up to Ecuador. A pulse of south winds there appears to be causing upwelling.  Cool water extends continuously from there over the Galapagos and continues along the equator out to 120W, a little stronger than weeks past. Cool water that had a larger footprint west of there out to at least 160W continues looking weaker, and is limited to pockets rather than being continuous, as if La Nina is retreating. La Nina is loosing control of surface waters of the Central Pacific, but is starting to make inroads into the East Pacific.
Hi-res 7 day Trend (11/19): A weak warming trend continues along Chile but is cooling along Peru to the Galapagos. West of there a  neutral trend was exhibited with pockets of warming and cooling waters present as they have been for months along the equator from the Galapagos to 160W but nowhere near as prominent as weeks and months past. Interesting. 
Hi-res Overview:
(11/19) A La Nina cool pool is most present in the Central Equatorial Pacific from 120W to 170E mainly in pockets. A thin continuous cool stream extends from the Galapagos to 120W on the equator a bit stronger than weeks past. La Nina is building in coverage to the east slightly, likely in it's mature phase.
Nino1.2 Daily CDAS Index Temps: (11/21) Today's temps stabilized at -0.477. We're a week and a half off a warm peak that was up to +0.7 degs on 11/10. 
Nino 3.4 Daily CDAS Index Temps: Today (11/21) temps were steady at -0.565. We're moving into a warmer pulse here since 11/5. Temps are oscillating warm to cool and back in 2-3 week cycles within a range from -0.3 to -1.0 degs.


Click for Full Sized Image

CFSV2 Forecast for Nino3.4 SST Anomalies

SST Anomaly Projections
CFSv2 Uncorrected Data (11/21) This model suggests La Nina held from July thru Oct 1 in the -0.55 deg range. The forecast has temps slowly warming from here forward with temps at -0.5 in early Dec and -0.4 degs Jan 1 rising steadily from there reaching neutral in March 2017 and up to +0.2 degs late April and holding in July. This is very interesting with the model holding the strength of La Nina at minimal ' La Nina' territory and then returning to neutral next summer.
IRI Consensus Plume: The mid-Nov Plume depicts temps have reached their peak minimum at -0.6. A slow increase in temps is forecast thereafter to -0.4 in Jan 2017 and neutral in April, starting to turn weakly positive after that to +0.1 in June. This is consistent with last months forecast and barely in La Nina territory. See chart here - link. 

Atmospheric Deco.cgiing (Indicating the presence of El Nino in the atmosphere driven by the ocean):
Southern Oscillation Index (11/21): The daily index is rising some after nose diving a few days ago, up to +2.35 today (was down to -27.55 on 11/16). It was well negative for most of October, then turned weakly positive for most of Nov other than the past week. The 30 day average was steady at -5.28. This strongly suggests the Active Phase of the MJO or some other mode of variability was having the same effect as the Active Phase of the MJO in early Nov. The 90 day average falling slightly +3.79. La Nina is trying to hang on, but not strongly.
ESPI (like SOI but based on satellite confirmed precipitation. Positive is good, negative bad): (11/21) Today's value was rising slightly at  -1.29. A peak low was reached on 11/2 at -1.94 the deepest it had been so far in this event suggesting La Nina was getting better established. But that is changing now, moving in a better direction.
Pacific Decadal Oscillation: The PDO continues positive, though much weaker lately (as expected with La Nina setting in).
Per NOAAs index recent values (Jan-Oct) are: +0.79, +1.23, +1.55, +1.59, +1.42, +0.76, +0.12 then falling to -0.90, -1.09 and -0.88 in Oct.
The Washington EDU index (Jan-Oct) are: +1.53, +1.75, +2.40, +2.62, +2.35, +2.03, +1.25 +0.52, +0.45 and +0.56 in Oct.
The PDO turned from a 6 year negative run (2008-2013) in early 2014 and has been positive until Aug 2016, the result of a turn towards La Nina. Looking at the long term record, it is premature to conclude that we have in-fact turned from the negative phase (La Nina 'like') to the positive phase (El Nino 'like'), but the data suggests that could be a real possibility. We've been in the negative phase since 1998 through at least 2013 (15 years). By the time it is confirmed (4-5 years out), we will be well into it.

See imagery in the ENSO Powertool


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

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