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Pacific Storm and Surf Forecast
Updated: Tuesday, May 3, 2016 4:27 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
2.0 - California & 1.0 - 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 4/18 thru Sun 4/24

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   

Weak Swell Pushing Up from SHemi
NPAC Shutting Down

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 3, 2016 :

  • Buoy 106 (Waimea Bay): Seas were 5.2 ft @ 8.3 secs with swell 4.0 ft @ 8.3 secs from 347 degrees.
  • Buoy 46025 (Catalina RDG): Seas were 3.5 ft @ 13.7 secs with swell 2.9 ft @ 13.6 secs from 213 degrees. Wind northwest 6-8 kts. Water temperature 60.8. At Santa Barbara swell was 2.8 ft @ 13.7 secs from 255 degrees. At Santa Monica swell was 2.5 ft @ 14.2 secs from 208 degrees. Southward from Orange County to San Diego swell was 3.3 ft @ 13.8 secs from 207 degrees.
  • Buoy 46012 (Half Moon Bay)/029 (Pt Reyes): Seas were 6.9 ft @ 14.3 secs with Gulf swell 5.6 ft @ 13.3 secs from 269 degrees. Wind northwest 6-8 kts. Water temp 51.4 degs.

    Notes

    Buoy 46059, Hi-res Buoys

PACIFIC OVERVIEW
Current Conditions
On Tuesday (5/3) in North and Central CA surf was 1 ft overhead and clean but with some light texture on top and mid-level fog making for June Gloom conditions. At Santa Cruz surf was 1-2 ft overhead on the set and top spots and glassy and a bit lined up. In Southern California up north waves were chest high with maybe bigger sets and clean and lined up. Very nice given the time of year. Down south waves were head high on the sets and clean and reasonably lined up. Swell was still working it's way south. Hawaii's North Shore was getting small windswell with sets in the waist high range at top spots and clean but a little warbled. The South Shore was small with set waves thigh to waist high at top spots and clean. The East Shore was getting windswell producing waves at thigh to waist high and chopped with moderate trades in effect.

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

Meteorological Overview
A weak gale developed 1200 nmiles north of Hawaii on Fri-Sat (4/30) producing 24 ft seas aimed east. That swell has past Hawaii and hitting the US West Coast now. And another system developed just off Japan Sat (4/30) producing up to 30 ft seas, but quickly dissipated before reaching the dateline. Swell is pushing towards Hawaii. There is hints that a small low might develop off California on Sun (5/8) producing 18 ft seas aimed east. And another gale is forecast off the North Kuril Islands at the same time with seas building to 27 ft aimed east. Down south another system formed southeast of New Zealand on Fri-Sat (4/30) lifting northeast with seas to 34 ft. Maybe some small swell to result. Perhaps an even smaller gale to form in the Central South Pacific on Sun (5/8) with 32 ft seas aimed east-northeast.

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

North Pacific

Overview
Jetstream
On Tuesday AM (5/3) the jet was falling consolidated off the Kuril Islands with winds near 140 kts forming a trough west of the dateline then ridging over the Western Gulf before falling into a steep trough positioned off Southern CA being fed by 120 kts winds, then ridging hard north pushing up into British Columbia. There was some support for low pressure development in that trough off CA. Over the next 72 hours both troughs are to ease east, with the Kuril trough moving to the dateline on Wed (5/4) being fed by 130 kts winds and looking solid, with the California trough moving closer but still off the coast being fed by 110 kts winds, and both supportive of gale development. More of the same is forecast into Fri (5/6) but with both troughs starting to get pinched with one north of Hawaii and the other mostly inland over the West Coast except bulging over water near Pt Conception. Support for gale development fading. Beyond 72 hours both trough to dissolve by Sat (5/7). But a decent flow is to still be pushing flat east off Japan on Mon (5/9) at 120 kts ridging slightly into the Western Gulf and forming trough off Kamchatka then falling into a new trough in the Central Gulf. Both are to be fed by 120 kts winds offering some support for low pressure if not gale development. The Kamchatka trough is to flatten out and die by Tues (5/10) though 150 kts winds to be flowing due east over the dateline. The Gulf trough is to dissipate at the same time. In all, not a bad pattern given the time of year.

Surface Analysis
On Tuesday (5/3) swell from a gale in the Gulf was hitting California (see Gulf Gale below). Also swell from a gale previous off Japan was pushing towards Hawaii (see Japan Gale below).

Over the next 72 hours despite good upper level support no solid gales are forecast down in lower levels of the atmosphere. Low pressure associated with the Japan-Dateline trough is to materialize in the Western Gulf on Wed-Thurs (5/5) generating a small fetch of 30 to maybe 35 kt west winds producing seas for 12 hours in the 19 ft range mid-day Thursday at 45N 161W. No swell of interest to result.

 

Gulf Gale
A small gale developed in association with a trough moving east over the Gulf of Alaska. On Fri AM (4/29) the gale had 35 kt west winds generating seas at 21 ft at 40N 167W aimed east. In the evening the gale built while racing east-northeast generating 40 kt west winds with seas building to 24 ft at 44N 159W (294 degs NCal) targeting the Pacific Northwest down into Central CA but mostly bypassing Hawaii. On Sat AM (4/30) winds were fading from 35 kts from the west with seas fading from 23 ft at 45N 152W. The gale is to dissipate after that. Small swell is expected for California with period at 13-14 secs.

North CA: Swell arrived as expected on Mon (5/2) building in the afternoon larger than expected to 6 ft @ 14 secs (8 ft). Swell to hold overnight fading Tues AM (5/3) at sunrise from 4.5 ft @ 12-13 secs (5.5 ft). Residuals fading Wed AM (5/4) from 4 ft @ 10-11 secs (4 ft). Swell Direction: 294 degrees

 

Japan Gale
A gale developed off Japan on Sat AM (4/30) with 45 kt west winds and seas building from 30 ft at 43N 155E. In the evening fetch is to fade from 35 kts with seas 28 ft at 42N 158E. Fetch is to be fading Sun AM (5/1) from 30-35 kts from the west winds seas 23 ft at 43N 162E. The gale is to be gone by evening with seas fading from 22 ft at 46N 168E. Small swell possible for Hawaii with luck.

Hawaii: Expect swell arrival on later Wed (5/4) building to 2.4 ft @ 16 secs (3.5-4.0 ft). Swell Continuing on Thurs (5/5) holding at 2.7 ft @ 14 secs (3.5-4.0 ft). Swell fading on Fri (5/6) from 2.4 ft @ 12-13 secs (3 ft). Swell Direction: 310 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 AM (5/3) light winds were in control of the coast with weak low pressure trying to build off the coast. Wednesday light northwest winds are forecast at 5 kts with low pressure moving closer. Light rain developing for the North Half of the state and the Sierras. Maybe some light snow for higher elevations late. Thursday light west winds continue at 5 kts. Light precip from Santa Barbara County northward late afternoon with light snow for mainly the Southern Sierra late afternoon. Light rain for Southern CA late too. Friday (5/6) no change is forecast with light winds and patchy showers mainly late afternoon with light snow of the Southern Sierras at higher elevations. No change Saturday with light winds but more rain now extending south into Southern CA through the day with light snow for the Southern Sierras later afternoon. Light winds on Sunday with rain and light snow confined to the Sierra. Monday northwest winds to 20 kts for North Ca and 15 kts down into Central CA. Precip is gone by sunrise. Light winds and clear skies Tuesday (5/10).

South Pacific

Overview
Surface Analysis  
On Saturday AM (4/30) swell from a storm previously in the Southeast Pacific was fading along the California Coast and expected to be gone by sunset.

Also small swell from a small gale southeast of New Zealand a week ago was fading in Hawaii and expected to be gone by late in the day.

A small gale formed well southeast of New Zealand over the weekend (see New Zealand Gale below).

Over the next 72 hours no swell production is forecast.

 

New Zealand Gale
A new gale developed south of New Zealand on Thurs PM (4/28) generating a small fetch of 45 kt southwest winds starting to get traction on the oceans surface. By Fri AM (4/29) a solid fetch of 45 kt south winds were in.cgiay in the deep Southwest Pacific with seas building from 27 ft at 62S 179W aimed north. That gale built more reaching storm status in the evening producing core fetch at 50 kts from the south aimed well north with seas starting to develop from 34 ft at 61S 172W. By Sat AM (4/30) a 1100 nmile long fetch of 35 kt south winds were in.cgiace with a core to 40 kts generating 32 ft seas at 59S 168W. The fetch faded in the evening from 30-35 kts lifting north generating 27 ft seas at 52S 164W. Fetch was gone by Sun AM (5/1) with seas dropping from 24 ft at 45S 159W.

Hawaii: Expect swell arrival on Fri (5/6) with swell building to 1.4 ft @ 16 secs (2.0-2.5 ft). Additional energy moving in Sat (5/7) at 1.5 ft @ 17 secs (2.5 ft). Swell still holding on Sun (5/8) at 2.2 ft @ 15 secs (3.0-3.5 ft). Residuals fading on Mon (5/9) from 1.8 ft @ 13-14 secs (2.0-2.5 ft). Dribbles left on Tues (5/10). Swell Direction: 185-190 degrees.

Southern CA: Expect swell arrival on Sun (5/8) building to 1.7 ft @ 18-19 secs (3 ft) later. Swell continues on Mon (5/9) at 2.5 ft @ 17 secs (4 ft). Swell holding on Tues (5/10) at 2.6 ft @ 16 secs (4 ft). Swell Direction: 205 degrees

North CA: Expect swell arrival on Sun (5/8) building to 1.4 ft @ 18 secs (2.5 ft) later. Swell continues on Mon (5/9) at 2.0 ft @ 17-18 secs (3.0-3.5 ft). Swell holding on Tues (5/10) at 2.2 ft @ 16 secs (3.5 ft). Swell Direction: 203 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 a new gale is forecast developing in the Gulf on Sun (5/8) producing a small area of 35 kt west winds and starting to affect the oceans surface producing a pinpoint of 18 ft seas at 40N 148W. Will believe it when it happens.

Also another gale is forecast developing off the Kuril Islands Sun PM (5/8) tracking east with west winds 35-40 kts into late Monday perhaps generating up to 26 ft seas at 48N 175E. Something to monitor.

But overall, the season is winding down if not over.

 
South Pacific

Beyond 72 hours a small gale is forecast developing in the Central South Pacific on Sat PM with 40 kts southwest winds and seas building from 28 ft at 54S 160W. By Sun AM (5/8) winds to build to 45 kts with seas 32 ft over a tiny area at 52S 149W. Fetch to fade from 35 kts in the evening with seas fading from 28 ft at 49S 140W. Small swell possible for the US West Coast but mostly focused Central America. Something to monitor.

More details to follow...

 

La Nina Continues to Build
MJO Turns Neutral

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 (5/2) no west winds were occurring in the Kelvin Wave Generation Area (KWGA). Anomalies were modest from the west at 180W-150W from 5S and points southward, but nowhere else. This is mostly attributable to El Nino.
1 Week Forecast (GFS Model): Weak west anomalies are forecast fading by 5/7. Neutral anomalies to follow.

Kelvin Wave Generation Area wind monitoring model: West and East

Longer Range MJO/WWB Projections:  
OLR Models: As of 5/2 a neutral MJO signal was over the dateline and the Maritime Continent. The Statistic model projects the exact same pattern holding for the next 2 weeks. The dynamic model depicts a weak Inactive pattern over the West Pacific and holding for the next 2 weeks. In all no enhancement of the jetstream is expected from the MJO.
Phase Diagrams 2 week forecast (ECMF and GEFS): (5/3) The ECMF model indicates the Active Phase of the MJO was collapsed in the Indian Ocean as weak as it can be. It is to perhaps slowly emerge in the Central Indian Ocean 2 weeks out. The GEFS model depicts the same thing.
40 Day Upper Level Model: (5/3) A weak Inactive Phase was developing in the far West Pacific and is to reach the dateline 5/13, tracking east into Central America through 5/28. A weak Active pulse to follow 5/23 tracking east into Central America through 6/12. With the change of season in.cgiay, it is unlikely an Active Phase will have any real positive impact.
CFS Model beyond 1 week (850 mb wind): This model suggests no MJO signal was present over the dateline. It also depicts west anomalies are weak over the dateline and are providing very limited fuel to support enhancing the jetstream and maybe storm production. The model depicts no MJO signal till 5/8 but weak west anomalies from El Nino are to hold in the KWGA into 5/18, then completely dissipate. A weak Inactive Phase of the MJO is to set up and hold into mid June. As of now, no east anomalies are forecast through July.

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

Subsurface Waters Temps
TAO Array: (5/3) 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 from 143W. Anomaly wise temps continue collapsing. One last little pocket of +1 deg anomalies exist tracking west between 170E to 145W and no more than 35 meters deep. This is the last of the El Nino subsurface warm reservoir. Cool subsurface waters are at depth racing east reaching Ecuador at -2 degs with -3 degs anomalies reaching east to 115W and getting ready to erupt. Instead of warm Kelvin Waves pushing east at depth, we now have a cold water river pushing east. Per the hi-res GODAS animation posted 4/28 the reservoir is all but gone with +1-2 degs above normal temps confined to a pocket between 170EW to 135W and 30 meters deep and tracking west. Cool waters at 3-4 degs below normal were undercutting it and upwelling near Ecuador. The onset of 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 : (5/2) The latest images (1.2 3.4) indicates cooler than normal water has taken over the equator region with negative anomalies extending west from Ecuador over the Galapagos to 138W peaking at -2 degs. Negative anomalies are also present along the immediate coast of Peru and Chile streaming northwest feeding the Galapagos cool pool. La Nina is in control of surface waters, though remnant El Nino warm water is 3 degs north and south of the equator and on the equator from 145W westward but getting undercut fast.
Hi-res 7 day Trend (5/2): A neutral trend has developed over waters off Peru but a cooler than normal trend continues along Columbia, Ecuador and over the Galapagos building out to nearly the dateline (165W). Cool subsurface water is upwelling to the surface driven by trades. The Warm pool is in total collapse.
Hi-res Overview:
(5/2) The El Nino signal is dissipating. A generalized pattern of +1-2 deg above normal temps remains 3 degs north and south of the equator and west of 160W. But a thin stream of cooler than normal waters are from Ecuador west over the Galapagos out to 160W and growing. Negative temps are building in the Nino1.2 region.

Other Sources
TAO Data: (5/2) +1.0-1.5 anomalies were over the equatorial Pacific advecting west from 160W to the dateline. Negative anomalies up to -1.0 were from Ecuador to 138W. The warm water signature was in steep decline.
Nino1.2 Daily CDAS Index Temps: (5/3) Todays temps were again on the decline at +0.280, down from +0.351 on 4/30, but those were up from -1.329 degs on 4/26
Nino 3.4 Daily CDAS Index Temps: Today (5/3) temps were falling some at +0.960 but generally continuing a steady decline that set in starting early February.

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


Pacific Counter Current:  As of 4/16 the current was strong from the east on the equator from 90W to 140E. Anomaly wise - they were strong from the east over the same area. There were no pockets of west anomalies indicated. La Nina is getting firmly entrenched based on this data, which is normal for this point in the El Nino lifecycle.

SST Anomaly Projections
CFSv2 Uncorrected Data
(5/3) indicates temps on a steady downward trajectory reaching normal (0.0) mid May falling -1.0 degs in early Aug, holding then easing down to -1.25 degs in Sept 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 Index's (lagging indicators rather than driving oceanic change):   
Southern Oscillation Index (4/30): The daily index was still well negative at -22.80, bouncing back from a near peak of -45.30 on 4/20 rivaling peak depths from Feb. The 30 day average was falling from -19.07. The 90 day average was falling from -14.68. El Nino was still quite evident in this index and the daily and 30 day averages suggested some form of Active MJO was in.cgiay.
SOI trend - Tahiti (looking for low pressure here): On 5/3 high pressure was building southwest of Tahiti. This same pattern to hold for the coming week. The SOI is expected to start steadily rising based on the Tahiti contribution likely shutting down any enhancement for the jetstream.
ESPI (like SOI but based on satellite confirmed precipitation): (5/3) Today's value was falling slightly at +0.97. 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.
Pacific Decadal Oscillation: 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 and up to +1.75 in Feb. Then in March it spiked to +2.40. 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 is the 3rd strongest El Nino since 1950 based primarily 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. 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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