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Pacific Storm and Surf Forecast
Updated: Monday, March 27, 2017 5:24 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 & 4.2 - 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 3/27 thru Sun 4/2

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   

Solid Swell Hitting Hawaii
Another Strong Gale Developing


On Monday, March 27, 2017 :

  • Buoy 106 (Waimea): Seas were 8.8 ft @ 15.4 secs with swell 7.3 ft @ 15.6 secs from 313 degrees.
  • Buoy 46025 (Catalina RDG): Seas were 6.0 ft @ 6.2 secs with swell 4.8 ft @ 6.1 secs from 264 degrees. Wind northwest 18-21 kts. Water temperature 59.4 degs. At Ventura swell was 2.8 ft @ 10.4 secs from 273 degrees. At Santa Monica swell was 1.9 ft @ 12.3 secs from 265 degrees. At Camp Pendleton swell was 2.6 ft @ 6.6 secs from 274 degrees. Southward at Pt Loma swell was 2.5 ft @ 13.2 secs from 255 degrees.
  • Buoy 46012 (Half Moon Bay)/029 (Pt Reyes): Seas were 8.4 ft @ 11.1 secs with swell 5.5 ft @ 10.2 secs from 286 degrees. Wind northwest 16-20 kts at the buoy. Water temp 54.9 degs.

    46006, 46059, New! Hi-Res Buoy Dashboards (at the bottom of the page)

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 (3/27) in North and Central CA northwest windswell was producing waves in the head high to 1 ft overhead range and warbled with whitecaps starting to appear early. Protected breaks were maybe shoulder high and nearly chopped early. At Santa Cruz surf was chest to head high on the sets and clean and lined up but weak and mushy. In Southern California up north surf was waist high and nearly chopped and mushy and weak. In North Orange Co surf was up to waist high and textured and weak and barely breaking. In San Diego surf was chest to shoulder high and relatively clean but ill formed and mushy. Hawaii's North Shore was getting Japan swell with waves 6-7 ft Hawaiian and clean and lined up coming from the west. The South Shore was flat and clean. The East Shore was getting east windswell at waist to chest high and chopped from easterly trades.

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

Meteorological Overview
On Monday (3/27) solid swell from a storm that tracked off Japan Wed-Thurs (3/23) with up to 43 ft seas aimed east then reached the dateline Fri (3/24) with 38 ft seas before stalling and fading on the dateline through Sun (3/26) with seas 32 ft was hitting Hawaii and bound for the US West Coast. Yet another smaller storm is forecast to follow a similar track off Japan to the dateline Tues-Wed 93/29) with up to 41 ft seas aimed east. A weaker but still decent gale pattern to follow with the jetstream holding together west of Hawaii. In the southern hemisphere a gale is forecast for the Central South Pacific Fri-Sat (4/1) with 34 ft seas aimed northeast. Will believe it when it happens.

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

North Pacific

On Monday AM (3/27) the jetstream was consolidated pushing strongly east off Japan with winds 190 kts reaching to the dateline with a new trough developing just off the coast offering good support for gale development. East of the dateline the jet weakened some with a hint of energy falling off the main flow south then turning east and tracking over Southern Baja while the more pronounced northern branch lifted gently northeast with winds rebuilding to 160 kts pushing up to British Columbia before falling south down and over the Central CA coast. There was a gentle trough just east of the dateline offering little support for gale development. Over the next 72 hours the Japan trough and associated energy is to track east reaching the dateline Wed (3/29) with winds still 180-190 kts offering continued support for gale development. The split point is to move to a point 900 nmiles north of Hawaii with the southern branch still tracking as it was before and the northern branch mostly tracking east into the Pacific Northwest. Beyond 72 hours a consolidated jet is to hold on Fri (3/31) running flat off Japan to a point north of Hawaii then lifting northeast pushing up into Central Canada with winds down to 130-140 kts over its length and the split continuing. No troughs are forecast with support for gale development diminishing. A variant of this pattern is to hold into Sun (4/2) with winds rebuilding off Japan to 160 kts but the split point retrograding to the dateline and a trough developing in the northern branch over the Western Gulf moving east into the Central Gulf later Monday (4/3) offering some decent support for gale development.

Surface Analysis
On Monday (3/27) swell from the first Dateline Storm was hitting Hawaii and bound for the US West Coast (see Dateline Storm below).

Over the next 72 hours another gale is to be developing off Japan on Mon PM (2/27) with 50 kt west winds starting to get traction on the oceans surface with seas building from 38 ft at 32N 153E over a tiny area. By Tues AM (3/28) winds to be 45 kt from the west and seas 37 ft over a tiny area at 33N 161E. In the evening west winds to continue at 45 kts approaching the dateline with 36 ft seas at 34N 171E. Fetch is to be building some from 45-50 kts on the dateline Wed AM (3/29) with seas 39 ft at 36N 178E. Fetch is to be fading from 40-45 kt in the evening with seas fading from 39 ft at 38N 175W targeting Hawaii well but also the US West Coast. Fetch is to move east Thurs AM (3/30) at 35-40 kts over a broad area with seas fading from 33 ft at 39N 166W aimed east. Fetch is to fade in the evening from 35 kts in the Western Gulf aimed east with seas 30 ft at 42N 161W. The gale is to fade out from there. Possible solid energy to target Hawaii with solid energy from the US West Coast. Something to monitor.


Dateline Storm
A storm developed off Japan on Tues PM (3/21) with west winds building from 50 kts and seas building from 31 ft at 34N 149E. By Wed AM (3/22) northwest winds were 50 kts with seas building from 41 ft at 34N 156E. In the evening the storm held with winds 50 kts but increasing in coverage with seas building to 43 ft at 34N 162E targeting Hawaii well. Fetch faded some Thurs AM (3/23) at 45 kts with seas fading from 42 ft at 34N 169E. The gale is to be lifting north some in the evening with winds 40-45 kts from the west over a broad area and seas fading from 38 ft at 37N 176E. Fetch to hold as it approaches the dateline Fri AM (3/24) with winds 40 kts from the west and seas 38 ft over a solid area at 39N 180E. fetch to build to 45 kts in the evening over the dateline with seas fading some at 36 ft at 40N 179W. Fetch is to be reorganizing at 35 kts Sat AM (3/25) from the west with seas from previous fetch fading from 32 ft at 43N 177W. In the evening secondary fetch is to rebuild at 40 kts from the west just west of the dateline with 24-25 ft seas at 42N 172W. Fetch building to 45 kt over a small area on the dateline Sun AM (3/26) with seas 32 ft over a small area at 42N 179E. This system is to fade in the evening with winds down to 30-35 kts from the west and seas 28 ft at 44N 174W. This system to fade out from there. Certainly something to monitor.

Hawaii: Swell fading Mon (3/27) from 5.9 ft @ 14-15 secs (8.5 ft). Swell continues on Tues (3/28) at 4.9 ft @ 13-14 secs (6.5 ft). Swell continues Wed (3/29) at 4.9 ft @ 13 (6.0-6.5 ft) secs. Swell fading Thurs (3/30) from 3.9 ft @ 12-13 secs (4.5-5.0 ft). Swell DIrection: 310-315 degrees

North CA: Expect swell arrival on Mon (3/27) pushing 4.5 ft @ 19 secs late (8.5 ft) but with much local windswell intermixed. Swell building on Tues (3/28) to 6.6 ft @ 17-18 secs (11 ft) but with much local northwest windswell intermixed. Swell continue on Wed (3/29) at 6.9 ft @ 15-16 secs (10.5 ft). Swell fading on Thurs (3/30) from 7.3 ft @ 14 secs (10 ft). Swell Direction: 286-292 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 (3/27) high pressure was taking control of the California Coast with northwest winds 15 kts for North and Central CA building to 20 kts later and into Southern CA too. Snow showers early for the Sierra. Tuesday (3/28) northwest winds take control at 20-25 kts early for North and Central CA. Southern CA to become protected. No precip (liquid or frozen) forecast. Wednesday (3/29) northwest winds forecast at 20 kts for all of North and Central CA fading to 15-20 kts later. A weak front with rain for North CA forecast after dark down to Pt Arena. Thursday high pressure is to start building in again later with northwest winds 20-25 kts for all of North and Central CA with light scattered rain for North and Central CA down to San Francisco mainly early. Northwest winds building into Southern CA late afternoon at 30 kts. Potential for snow for Tahoe and the Sierra late afternoon into the evening. Friday high pressure is to be in control with northwest winds 25-30 kts early for the entire state fading in Southern CA later. Saturday high pressure and northwest winds continue for North and Central CA at 20-25 kts but calm for Southern CA. More high pressure builds in Sunday with north winds 20-25 kts for all of North and Central CA. More of the same Monday at 25-30 kts and building into Southern CA mid- morning. Spring is here and setting up strongly.


South Pacific

Surface Analysis  
No swell producing fetch has occurred 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 hours a small secondary gale is forecast forming in the Northwestern Gulf on Fri PM (3/30) with 35-40 kt west winds and seas building from 22 ft at 35N 175E. On Sat AM (4/1) 35-40 kt west winds to continue tracking east-northeast with 23 ft seas at 38N 177W. The gale is to wrap up lifting northeast in the evening with winds 40 kts from the west over a small area with seas 28 ft at 43N 172W. On Sun AM (4/2) fetch to fade from 35 kts in the Northwestern Gulf with seas 30 ft at 46N 167W. The gale to dissipate from there. Perhaps small swell to result for Hawaii and CA.

South Pacific

A gale is projected forming in the Central South Pacific on Sat (4/1) producing 40-45 kt south winds with seas peaking at 31 ft at 60S 138W in the evening aimed north. Something to monitor.

More details to follow...


Inactive MJO Holding but the Models Suggest Otherwise

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 equator it is in control of, and in it's Active Phase by slackening if not an outright reversing trade winds while enhancing 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 planet, 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 in the Pacific help support the formation of El Nino. During the Inactive Phase the jet stream tends to split resulting in high pressure and less potential for swell producing storm development. Wind anomalies in the Kelvin Wave Generation Area (KWGA) are key for understanding what Phase the MJO is in over the Pacific. The KWGA is located on the equator from 135E-170W and 5 degs north and south (or on the equator from New Guinea east to the dateline). West wind anomalies in the KWGA suggest the Active Phase of the MJO in the Pacific, and east anomalies suggests the Inactive Phase. In turn the Active Phase strengthens and the Inactive Phase weakens the jetstream, which in turn enhances or dampens storm production respectively in the Pacific.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: La Nina started developing in early 2016, but westward displaced and generally weak. And by March 2017, it was fading with suspicious warming developing along South America and over the Galapagos to a point south of Hawaii. Still, the atmosphere is in a La Nina configuration.

KWGA/Equatorial Surface Wind Analysis & Short-term Forecast:
Analysis (TAO Buoys): As of Sun (3/26) east winds were over the entire equatorial Pacific and the Kelvin Wave Generation Area. Anomalies were neutral to light westerly over the equatorial East Pacific but east anomalies were rebuilding over the KWGA. La Nina's remnants in the atmosphere have not given up yet.
1 Week Forecast (GFS Model): Moderate east anomalies were modeled over the Kelvin Wave Generation Area attributable to the Inactive Phase of the MJO. The forecast suggests moderate east anomalies to hold over the heart of the KWGA for 2 more days through 3/29, then start fading with near neutral anomalies by 4/3. This suggests the Inactive Phase of the MJO and La Nina is in control of the KWGA and is to hold for a few more days.

Kelvin Wave Generation Area wind monitoring model: West and East

Longer Range MJO/WWB Projections:  
OLR Models: As of 3/26 a very weak Inactive MJO was indicated over the West Pacific. The statistic model projects it holding unchanged for the next 2 weeks. The dynamic model depicts the same thing. The good news is the two models are in sync. The bad news is they show no signs of the Active Phase of the MJO, contrary to what the CFS model indicates (below).
Phase Diagrams 2 week forecast (ECMF and GEFS): (3/27) The ECMF model indicates the Active Phase of the MJO was indiscernible over the Maritime Continent and is to forecast to stay there for the next 2 weeks unchanged. The GEFS model depicts the same thing. This model runs about a week ahead of what occurs down at the surface.
40 day Upper Level Model: (3/27) This model depicts a modest Active Phase present centered over the Maritime Continent tracking east over the West Pacific fading on 4/1 then to the dateline and Central America 4/16. It is to be followed by a very weak almost neutral pattern after that through 5/6. This model runs about 2 weeks ahead of what happens at the surface. The MJO is moving fast but to not as strong as previously projected.
CFS Model - 3 month (850 mb wind): (3/27) This model depicts the Active Phase over the KWGA today but with moderate east anomalies still in control. The Active Phase was still centered over the Maritime continent reaching east to the dateline. Beyond the Active Phase is to stall on the dateline through 4/4 but with east anomalies still in control of the KWGA then finally giving way to a neutral wind trend. West anomalies are to be developing by 4/6 and building solid by 4/12 as the Active Phase of the MJO builds solid over the dateline and not fading for the foreseeable future with nary a hint of east anomalies. 3/28 was the anchor date for the final demise of east anomalies (but today's update suggests 4/4). La Nina is to be gone per the low pass filter on 5/6 (slipping from 4/28) with El Nino taking hold 5/22 (previously 5/8). Projected west anomalies are dependent upon the evolution of El Nino and the date of that development has been continuously slipping.
Confidence very low on this forecast. We'll see what happens.

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

Subsurface Waters Temps
TAO Array: (3/27) Actual temperatures remain stratified with warm water in the West Pacific at 30+ degs C retrograding west and no longer on the chart. The 28 deg isotherm line is steady at 175E and steep still suggesting a hard break between warm water in the west and cool water in the east at depth. But 26 deg anomalies continue building to the east reaching to the Galapagos over a shallow pool down 40 meters (75 meters at 140W) and holding. Anomaly wise warm anomalies at +1 degs rule the entire upper reaches of the equatorial Pacific from 100 meters upward. A pocket of -1 degs anomalies is easing west at depth between 120-170W down 125 meters. The hi-res GODAS animation posted 3/19 depicts that warm water had built east forming a continuous path from the West Pacific to Ecuador at +0.5-1.0 degs suggesting a Kelvin Wave has in flight, but is now showing signs of weakness and breaking up from the dateline to 120W. La Nina has lost control of the ocean at depth with something that almost resembles a warm pattern taking shape. The concern is there is not much warm water in the far West Pacific to feed any sort of a progressive Kelvin Wave pattern.
Sea Level Anomalies: (3/19) The previous upgrade where positive anomalies were depicted at 0-+5 cms on the equator from Ecuador west to 140W in one continuous thin stream has broken up extending from Ecuador to 115W now, but not west of there. La Nina is gone in the East Pacific with a neutral trend building in.

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: (3/26) The latest images (1.2 3.4) indicate warm water dominating the region extending from Northern Chile over Peru and north to Ecuador then extending west over the Galapagos with the warmest anomalies reaching now west to 105W at 2+ degs but with solid warm anomalies out to 160W. This warm pool is showing signs of weakness as of today, but is still solid in coverage. Most warming is in the southern hemi limited to Nino1.2 and trying to build into the Nino3.4 region. Temps are +2-4 degs above normal along the immediate South American coast and advecting west along the equator. Impressive. And these waters extend east thousands of miles off the coast as far south as 25S. La Nina is gone and it looks like an El Nino like pattern is returning, though that seems hard to believe given the limited volume of subsurface warm water in the West equatorial Pacific.
Hi-res 7 day Trend (3/26): A cooling trend covers waters of north of Ecuador to the Galapagos. A warming trend extends west from there out to the dateline. A warming trend is also present in the Northern Hemi off California and out over Hawaii and reaching to the Philippines. But that will likely be shut down shortly as north winds build there.
Hi-res Overview:
(3/26) There is no sign of La Nina east of 160W. A solid warm regime holds from Ecuador west to 120W and building but less energetic out to 160W. Remnants of La Nina continue from 160W-170E. It almost looks like El Nino is trying to develop and making headway into the Nino3.4 region.
Nino1.2 Daily CDAS Index Temps: (3/27) Today's temps were falling at +1.208, down from the peak of +3.0 degs on 3/18.  
Nino 3.4 Daily CDAS Index Temps: Today (3/27) temps were falling slightly at +0.079 degs, and not remarkable like Nino1.2 was.

Click for Full Sized Image

CFSV2 Forecast for Nino3.4 SST Anomalies

SST Anomaly Projections
CFSv2 Uncorrected Data (3/27) The forecast has temps at +0.35 degs mid-March building to +0.55 degs early April and +0.9 degs later in April building to 1.0 degs in July and building through the summer rising to +1.2 degs in Sept and +1.4 degs in Oct suggesting a return of El Nino. This is a bit of an upgrade from previous runs that had temps to +1.3 degs or more. Regardless, La Nina is over and a return to at least normal temps is expected in Spring. The change in the atmosphere will be slower. And a turn to weak El Nino conditions is possible late summer into Fall. Still, there is no source from grater warming with the warm pool in the far West Pacific pretty weak.
IRI Consensus Plume: The mid-March Plume just updated today (3/16) and depicts temps are warming and are now at +0.3 degs. A slow increase in temps is forecast thereafter to +0.8 degs in July holding into the Fall. This is +0.3 degs warmer than the Feb forecast and +0.6 degs warmer than the January forecast and suggests La Nina is over and a warmer regime is setting up. See chart here - link. 

Atmospheric Decoupling (Indicating the presence of El Nino in the atmosphere driven by the ocean):
Southern Oscillation Index (3/27): The daily index was positive at +5.93 and has been running positive the last 12 days. The 30 day average was rising at +4.25. The 90 day average was rising at 0.88 or effectively neutral. This suggests a return to at least a neutral ENSO conditions has taken hold.
ESPI (like SOI but based on satellite confirmed precipitation. Positive is good, negative bad): (3/27) Today's value was rising at -0.91, still pretty negative given the other oceanic signals. A peak low was reached on 11/2 at -1.94 the deepest it had been in this La Nina event. This measures atmospheric response, not oceanic. The atmosphere lags behind changes in the ocean. The expectation is this index will rise to 0.0 three months after the oceanic change occurred (Oceanic change occurred approx Jan 20 2017). So on March 20 the index should be neutral. That seems like a reach.

Pacific Decadal Oscillation: The PDO continues positive, though much weaker lately (as expected with La Nina setting in).
Per NOAAs index recent values (Jan-Dec): Jan 2017 = +0.21, Feb = +0.08. This continues to look like the warm phase of the PDO. No consistently negative readings have occurred since Feb 2014
The Washington EDU index (Jan-Dec): Jan 2017 = +0.77, Feb = +0.70. No negative readings have occurred since Dec 2013
The PDO turned from a 16 year negative run (Jan 98-Feb 2014) in early 2014 and has been positive ever since (other than a few months of negative readings in Fall 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 strongly suggests that could be a possibility. 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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