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Pacific Storm and Surf Forecast
Updated: Tuesday, May 17, 2016 5:34 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
3.5 - California & 1.0 - Hawaii
Using the 'Summer' 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 5/16 thru Sun 5/22

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   

Small S.Hemi Swell Continues for CA
Southeast Pacific Holds Hope Longterm

Swell Classification Guidelines

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/Utility Class: 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.

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

BUOY ROUNDUP
On Tuesday, May 17, 2016 :

  • Buoy 146 (Lanai): Seas were 1.8 ft @ 11.8 secs with swell 0.8 ft @ 12.4 secs from 197 degrees.
  • Buoy 46025 (Catalina RDG): Seas were 3.6 ft @ 15.9 secs with swell 1.6 ft @ 15.6 secs from 191 degrees. Wind southwest 6-8 kts. Water temperature 63.9. At Santa Barbara swell was 2.4 ft @ 11.7 secs from 266 degrees. At Santa Monica swell was 2.3 ft @ 16.1 secs from 203 degrees. Southward from Orange County to San Diego swell was 2.3 ft @ 15.9 secs from 193 degrees.
  • Buoy 46012 (Half Moon Bay)/029 (Pt Reyes): Seas were 8.5 ft @ 9.1 secs with northwest windswell 6.2 ft @ 8.6 secs from 316 ad southern hemi swell 1.8 ft @ 16.8 secs from 196 degs. Wind northwest 12-14 kts. Water temp 54.1 degs.

    Notes

    Buoy 46059, Hi-res Buoys

PACIFIC OVERVIEW
Current Conditions
On Tuesday (5/17) in North and Central CA surf was waist high and chopped from local northwest winds. At Santa Cruz small southern hemi swell was still hitting producing waves at waist to chest high and clean early but inconsistent. In Southern California up north waves were waist high and clean but sporadic. Down south southern hemi swell was producing waves at waist to chest high with a larger sets and clean early. Hawaii's North Shore was flat and clean. The South Shore was getting rare waist high sets and clean early. The East Shore was getting east tradewind windswell at thigh high and chopped by east trades.

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

Meteorological Overview
One last small gale is tracking through the Gulf of Alaska on Mon-Tues (5/17) producing 22-24 ft seas aimed east. No other obvious swell producing fetch is to follow other than windswell. Down south a small gale formed southeast of New Zealand on Sat (5/7) with seas to 33 ft over a small area gently lifting northeast into Sunday (5/8) and two additional patches of fetch followed over the same area of the South Pacific through Wed (5/11) with seas ranging from 28-32 ft aimed northeast. Small swell from the first pulse is hitting California now. After that, the models fortunately are suggesting a gale forming in the far Southeast Pacific on Mon-Tues (5/24) generating seas to 38 ft aimed due north. So there's some hope on the charts. We are fully in a summer swell pattern now.

SHORT- TERM FORECAST
Current marine weather and wave analysis.cgius forecast conditions for the next 72 hours

North Pacific

Overview
Jetstream
On Tuesday AM (5/17) the jet was consolidated pushing hard northeast off Japan reaching over Kamchatka then falling hard southeast with winds to 140 kts reaching south to 33N forming a trough over the dateline and offering good support for gale development. From there the jet lifting steadily east-northeast with winds 90 kts eventually pushing into North British Columbia. A weak trough was embedded in it in the Gulf tracking northeast and offering minimal support for gale development. Over the next 72 hours the trough on the dateline is to start getting pinched off on Wed (5/18) while easing east and weakening but not fully pinching off while lifting northeast into Fri (5/20) and dissolving. Limited support for gale development expected. A trough is forecast building over the US West Coast on Thurs (5/19) reaching south to Monterey Bay on Sat (5/21) before moving fully onshore. No swell generation is expected but maybe some rain for California. Beyond 72 hours by Sat (5/21) a very weak and fragmented jetstream pattern is to take over forecast with no cohesive flow indicated and winds no more than 90 kts in any pocket offering no support for gale development through the 180 hours mark. The transition to summer will be complete at that time and we'll start monitoring the Southern Hemi jetstream.

Surface Analysis
On Tuesday AM (5/17) swell from a gale in the Gulf of Alaska was in the water pushing towards California (see Gulf Gale below).

Otherwise no swell production of interest is forecast other than local windswell.

The local California pressure gradient is already active with 25 kt north winds off North Ca and it is expected to be reinvigorated starting Thurs AM (5/19) driven by a 1036 mbs high anchored in the Gulf of Alaska and interacting with low pressure forecast just inland over Nevada producing 30 kt north winds over North CA down to Monterey Bay resulting in local windswell. See QuikCASTs for details.

 

Gulf Gale
On Sunday AM (5/15) a low pressure system developed in the Western Gulf with pressure 992 mbs generating 25 kt northwest winds. By evening west winds built to 40 kts with seas building to 18 ft at 41N 162W targeting Hawaii and the US West Coast and starting to lift northeast. A decent sized fetch of 35 kt west winds was lifting northeast on Mon AM (5/16) with seas 22 ft at 44N 156W (295 degs NCal). In the evening fetch built to near 40 kts from the west with seas building to 24 ft tracking northeast at 47N 150W (302 degs NCal). On Tues AM (5/17) the fetch was just off British Columbia at barely 30 kts from the west with 21 ft seas fading at 48N 144W targeting Vancouver Island (310 degs NCal). Small swell is expected from the US West Coast with period at 13 secs.

North CA: Expect swell arrival on Thurs (5/19) at 6 AM at 5.5 ft @ 13-14 secs (7.5 ft) but buried in local windswell. Swell Direction: 295-302 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 Tuesday (5/17) high pressure was just off the coast at 1028 mbs ridging into Washington generating the usual pressure gradient and north winds along mainly the North Coast at 25 kts generating windswell but also making for generally poor conditions down to Pt Conception. Wednesday AM the standard summer time pressure gradient is to remain in.cgiay with 25 kt north winds over North CA but a lighter flow in Central CA (10 kts) and an eddy flow in Southern CA. But on Thursday high pressure is to fall south some with low pressure falling south inland over Nevada generating northwest winds at 30 kts over North CA southward down into Central CA to Monterey Bay with 20 kts north winds down to Pt Conception perhaps reaching into Southern CA late afternoon. But by Friday (5/20) the gradient is to start dissolving with a 15 kt northwest flow for North and Central CA late afternoon. Light rain for the North Coast. northwest winds to be weaker still on Saturday (10 kts for North and Central CA) and rain falling south to Monterey Bay by 4 PM. On Sunday northwest winds to hold at 10 kts for North and Central CA and the Channel Islands but less for Southern CA. Rain dissipating everywhere but scattered showers late for extreme north CA and the Sierra. Monday (5/23) northwest winds at 10 kts forecast for North and Central CA then building some on Tues (5/24) to 15 kts from Pt Conception northward.

South Pacific

Overview
Surface Analysis  
On Sunday AM (5/15) swell from a gale that formed Fri-Sun (5/8) in the South Central Pacific was pushing northeast (see South Pacific Gale below).

Over the next 72 hours no swell production is forecast.

A solid but compact storm is forecast developing in the Tasman Sea on Thurs (5/19) with seas to 46 ft late at 43S 162E (Central Tasman Sea). The storm to move east-northeast on Fri AM (5/20) with seas 44 ft at 40.5S 168E. The gale to be fading from 36 ft in the evening at 37.5S 171.5E and becoming shadowed by New Zealand. Large swell possible for Fiji with small sideband and filtered swell for Hawaii.

 

South Pacific Gale
A small compact storm started forming south of New Zealand on Fri (5/6) with 50 kt west winds and seas building from 30 ft at 57S 168E. Winds faded to 40 kts then rebuilt to 45 kts in the evening with seas building to 31 ft over a tiny area at 57S 177W, pushing more southeast than east. Fetch faded while tracking east Sat AM (5/7) from 40-45 kts with seas building to 34 ft at 57S 165W. 40 kt southwest fetch finally took hold in the evening but seas were fading from 31 ft at 56S 154W aimed better to the northeast. 40-45 kt south fetch held Sun AM (5/8) lifting well north with seas 33 ft at 53S 149W. In the evening 40 kt south fetch started fading with seas still 32 ft at 50S 143W. The gale to dissipate after that. Decent unshadowed swell to result for California (196-203 degrees).

Additional 50 kt west-southwest fetch built over the West Pacific on Mon AM (4/9) with 32 ft seas building over a small area at 59S 160W. Fetch faded from 40 kts in the evening with seas 33 ft at 56S 154W. A broad area of 35 kt southwest fetch faded Tues AM (5/10) with seas fading from 28 ft 54S 148W. Additional background swell was being generated targeting Peru up into Central America with sideband swell into California.

Additional fetch developed over the same area on Tues PM (5/10) with southwest winds 40 kts and seas 26 ft at 51S 158W. Wed AM (5/11) 35-40 kt south fetch was in control with seas building to 28 ft 44S 150W. That fetch held into the evening with seas 27 ft at 45S 140W. Fetch faded from there.

Southern CA: Swell fading Tues (5/17) from 2.5 ft @ 15-16 secs (4 ft). Swell fading some on Wed (5/18) from 2.3 ft @ 14 secs (3 ft) with new energy building underneath at 2 ft @ 17-18 secs late (3.5 ft). A new pulse of energy building on Thurs (5/19) from 2.6 ft @ 16-17 secs (4.0-4.5 ft). Swell fading Fri (5/20) from 2.7 ft @ 15 secs (4.0 ft). residuals fading out on Sat (5/21) from 2.3 ft @ 14 secs early (3.0-3.5 ft). Swell Direction: 200 degrees.

North CA: Swell holding Tues (5/17) at 2.0 ft @ 16 secs (3.0-3.5 ft). Swell fading Wed (5/18) from 1.7 ft @ 14-15 secs (2.5 ft). Additional swell arriving on Thurs (5/19) pushing 2.0 ft @ 16-17 secs (3.0-3.5 ft). Swell fading Friday (5/20) from 2.2 ft @ 15 secs (3.0 ft). Residuals fading Sat (5/21) from 2 ft @ 14 secs(2.5-3.0 ft). Swell Direction: 195-197 degrees.

 

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

 

QuikCAST's

 

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

North Pacific

Beyond 72 hours no other swell producing fetch is forecast.

 
South Pacific

Beyond 72 hours a gale is forecast developing in the far Eastern South Pacific on Mon AM (5/23) producing an elongated fetch of 45 kt south winds at 123W. Seas building from 30 ft at 35S 123W. This is to be very far north of normal. 55 kt south winds to build in the evening a bit further south with 36 ft seas building at 40S 123W. 50 kt south winds to hold on Tues AM (5/24) with 38 ft seas aimed north. Solid swell potential for Mexico up into California assuming this system develops as forecast.

More details to follow...

 

La Nina Gains More Momentum
Negative Anomalies Increasing Coverage over Equator

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 fading out. La Nina is emerging.

KWGA/Equatorial Surface Wind Analysis & Short-term Forecast:
Analysis (TAO Buoys): As of Mon (5/16) east winds were over the entire equatorial Pacific including the Kelvin Wave Generation Area (KWGA) except for one small patch of calm winds near 160E and south of the equator. Anomalies were neutral over the entire region, other than weak west anomalies in the aforementioned area of calm winds.
1 Week Forecast (GFS Model): East anomalies are over the KWGA and are forecast building through 5/19 to strong levels then fading some into 5/24. La Nina is building.

Kelvin Wave Generation Area wind monitoring model: West and East

Longer Range MJO/WWB Projections:  
OLR Models: As of 5/16 a modest Inactive MJO signal was over the West Pacific and dateline regions. The Statistic model projects this pattern fading with a moderate Active pattern taking control 2 weeks out. The dynamic model depicts the Inactive pattern slowly fading but still present over the dateline 2 weeks out with the Active Phase in the Indian Ocean trying to move west, but not making it and fading some. In all no enhancement of the jetstream is expected from the MJO and if anything some suppression of it is possible attributable to the Inactive Phase of the MJO.
Phase Diagrams 2 week forecast (ECMF and GEFS): (5/17) The ECMF model indicates the Active Phase of the MJO holding strength while moving east in the Indian Ocean but not reaching the Maritime Continent at moderate strength, then collapsing 2 weeks out. The GEFS model depicts the same thing.
40 Day Upper Level Model: (5/12) A modest Inactive Phase was in the Central Pacific and is to reach Central America 5/20. A weak Active pulse to follow starting 5/25 in the far West Pacific tracking east into Central America through 6/10. Another Inactive Phase is to start in the West Pacific on 6/8 moving almost to Central America on 6/21. With the change of season in.cgiay, it is unlikely the MJO will have any real positive impact on storm production, but it speaks to the possible buildup of La Nina longer term.
CFS Model beyond 1 week (850 mb wind): This model suggests a weak Inactive Phase of the MJO was building over the dateline with light east winds in.cgiay offering no fuel to support enhancing the jetstream. The model depicts the Inactive Phase of the MJO and modest east anomalies in the KWGA through 5/25. A weak Active Phase to follow starting 5/26 producing only neutral anomalies through 7/12. After that the MJO is to be weak with no real anomalies into 8/14. El Nino is dead per this model no west anomalies or interest forecast.

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

Subsurface Waters Temps
TAO Array: (5/17) Actual temperatures continue to retreat daily. A pocket of 29-30 deg temps were building in the far West Pacific with the 28 deg isotherm line retreating west to 149W. Anomaly wise temps continue collapsing fast. The last pocket of El Nino anomalies has vaporized. Neutral anomalies rule from the West Pacific to the East down to 50 meters. Cool subsurface waters are at depth racing east reaching Ecuador at -1 degs with -3 degs anomalies reaching east to 127W. This cool pool is already erupting near Ecuador. Instead of warm Kelvin Waves pushing east at depth, a cold river is rushing east. Per the hi-res GODAS animation posted 5/13 the reservoir is effectively gone with +0.5 deg anomalies confined to a shrinking pocket between 175E to 155W and 30 meters deep and tracking west. Cool waters at 3-4 degs below normal were in.cgiay in the under the entire width of the equator, undercutting the warm pool above it and upwelling near Ecuador. La Nina has begun.

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: (5/16) The latest images (1.2 3.4) indicates cooler than normal water continues over the equator region with negative anomalies along the coast of Peru pushing north and then extending west from Ecuador over the Galapagos building west to 157W peaking at -1.5 degs but mostly -0.5-1.0 degs. La Nina is in control of surface waters, though remnant El Nino warm water is 3 degs north and south of the equator. No warm water remains anywhere in the Nino regions on the equator.
Hi-res 7 day Trend (5/16): A cooler than normal trend continues from the Galapagos west out to 160W and if anything is building robustly. And a mirror image of that is now showing up in the Atlantic tracking west from Africa almost reaching Brazil. Temps are warming along the California coast due to relaxing of high pressure and north trades there, at least for the moment.
Hi-res Overview:
(5/16) The El Nino signal is dissipating. Cooler than normal water is tracking from Ecuador and building in width on the equator from west of the Galapagos out to near 160W. A generalized pattern of +1-2 deg above normal temps remains 3 degs north and south of the equator and west of 160W. Cooler water is over the dateline in the North Pacific looking very much like the classic Active PDO pattern.

Nino1.2 Daily CDAS Index Temps: (5/17) Today's temps were steady at +0.570.
Nino 3.4 Daily CDAS Index Temps: Today (5/17) temps continued crashing hard since 5/10, and are now at +0.275 degs.

Comparing Stongest El Ninos in the last 50 year - ERSSTv4 'centered' data


Pacific Counter Current:  As of 5/7 the current was strong in pockets from the east on the equator from 90W to 150E and consistently moderate east over that region. Anomaly wise - they were strong from the east over the same area. There were no pockets of west anomalies indicated. La Nina is firmly entrenched based on this data, which is normal for this point in the El Nino lifecycle.

SST Anomaly Projections
CFSv2 Uncorrected Data (5/17) indicates temps on a steady downward trajectory reaching normal (0.0) mid-May, falling to -1.0 degs early July, then easing down to -1.15 degs in early Aug stabilizing there into Jan 2017. This is in solid La Nina territory.
IRI Consensus Plume: The mid-April Plume depicts temps falling steadily from here forward, down to -0.8 by December. See chart here - link. 

Atmospheric Co.cgiing (Indicating the presence of El Nino in the atmosphere driven by the ocean):   
Southern Oscillation Index (5/17): The daily index was steady at 0.10. The 30 day average was rising from -8.32, with the most recent low peak at -19.07 (4/30). The 90 day average was rising from -12.49. El Nino was still evident in the 30 and 90 days averages.
SOI trend - Tahiti (looking for low pressure here): On 5/17 a weak pressure pattern was southwest of Tahiti. It is to build some on Sat (5/21) for a few days, then start fading again on Tues (5/24). The SOI is expected to hold based on the Tahiti contribution and not provide any enhancement for the jetstream.
ESPI (like SOI but based on satellite confirmed precipitation): (5/17) Today's value was falling from +0.64. It peaked recently on 3/12 at +1.57 then fell until 4/14, when it started rising again peaking 4/23 at +1.12. It has been falling ever since.
Pacific Decadal Oscillation: The PDO continues to rise. April's value was +2.62, the highest it's been since 1941. The PDO turned from a 6 year negative run (2008-2013) in early 2014 and has been mostly above +1.5 all of 2015. In Jan 2016 it was +1.53 up to +1.75 in Feb, then spiking to +2.40 in March and +2.62 in April. Impressive. 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.

Conclusion: This El Nino was the 3rd strongest El Nino since 1950 based on the MEI. Centered Monthly Nino3.4 data suggests it is the strongest. Based on California precipitation, this one does not compared to any major El Nino in recent memory due to it's westward di.cgiacement. Based on surf, El Nino has had the expected effect producing 13 significant class swells in the North Pacific (16 expected). From a pure El Nino perspective, this event is over and transitioning towards La Nina. But from a teleconnection standpoint, the warm pool in Nino3.4 is still imparting solid energy to the atmosphere and momentum will affect the upper atmosphere into the late Fall of 2016.

The question now turns to how much the jet will be enhanced by remnants of El Nino for the Fall and Winter of 2016-2017. It's too early to know anything definitive yet, but with the PDO still positive, it is possible the transition to La Nina may not be a strong as in past events.

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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