BUOY ROUNDUP
Tuesday, December 9, 2025 :

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.

PACIFIC OVERVIEW
Current Conditions
On Tuesday (12/9) in North and Central CA surf was head high to slightly overhead on the sets and real lined up if not occasionally closed out and clean with brisk offshore winds early. Protected breaks were up to chest high and lined up of not a bit closed out but soft and clean early. At Santa Cruz surf was waist to chest high and modestly lined up with good form and clean but soft. In Ventura County waves were up to thigh high on the sets and weakly lined up and soft but clean. Central Orange County had sets at waist high and lined up with decent form and clean but pretty soft. South Orange County's best summertime breaks had some waist high sets and lined up and clean with decent form and soft. North San Diego had sets at thigh to waist high and lined up with good form but soft and clean early. Oahu's North Shore had sets at head high to 1 ft overhead and lined up with good form and real clean early. The South Shore was flat and clean but with east lump running through it. The East Shore was getting minimal tradewind generated east windswell at thigh high and warbled from modest east trades early.

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

Meteorological Overview
On Tuesday (12/9) Hawaii was getting some swell from a gale that developed just off the Kurils on Thurs (12/4) producing 24-26 ft seas aimed briefly east. California was getting sideband energy from low pressure previously off the Pacific Northwest. A modest gale tracked east-southeast from just west of the dateline Sat-Tues (12/9) eventually reaching the Central Gulf producing 26-27 ft seas aimed southeast at Hawaii and then east at the mainland well. After that a small gale is to lift north from just west of the dateline Wed-Thurs (12/11) producing 33-37 ft seas aimed east. And maybe a small system is to develop off the Kurils on Mon (12/15) producing 40 ft seas aimed briefly east but not making any east headway. A pretty muddled storm pattern is forecast.

See all the details below...

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

North Pacific

Overview
Jetstream
On Tuesday (12/9) the jetstream was weak and consolidated pushing off Japan on the 34N latitude line at 150 kts fading to 120 kts while tracking to the dateline, losing definition there then reappearing north of Hawaii while lifting northeast and tracking over Vancouver Island with winds building to 140 kts making for weather there. A bit of a split was developing west of the dateline. with no trough evident offering no obvious support for gale formation. Over the next 72 hours more of the same is forecast but with a clear split developing over the dateline with energy in the split tracking north well up into the North Bering Sea on Wed-Thurs (12/11) and not cutting off and becoming separate till late Fri (12/12). Still no troughs are forecast. Beyond 72 hours starting Sun (12/14) the jet is to start reorganizing more or less consolidated running from Japan up into Vancouver Island with winds building to 180 kts over Japan ridging northeast slightly then falling into a weak trough over the dateline with winds only 100 kts there before tracking northeast again but with winds only 120 kts pushing up into the Pacific Northwest. The dateline trough is to become more organized on Mon (12/15) being fed by 170 kt winds starting to support gale formation while pushing east into Tues (12/16) with it's apex just 300 nmiles northwest of Hawaii. At least there is some support for gael formation now on the charts. But the Inactive MJO is to be still lingering.

Surface Analysis
On Tuesday (12/9) weak swell was hitting Hawaii from a fragmented gale previously just off the Kuril Islands (see Kuril Gale below). And weak swell was hitting California from low pressure previously in the North Gulf (see North Gulf Low Pressure below).

Over the next 72 hours swell is to be hitting Hawaii and California originating from a gale that developed over the dateline (see Another Dateline Gale below).

And a gale is forecast developing just west of the dateline on Wed AM (12/10) producing 45 kts west winds and seas building. In the evening the gael is to be lifting north with northwest winds 45-50 kts and seas 36 over a tiny area at 39N 166E aimed southeast at Hawaii. On Thurs AM (12/11) the storm is to track north with 55 kt northwest winds and seas briefly 37 ft at 42.5M 168.5E aimed southeast. Fetch fading in the evening from 40 kts with seas fading from 26 ft at 42N 169E aimed southeast. The gael to dissipate from there. maybe some swell to result for Hawaii.

North Gulf Low Pressure
On Sun AM (12/7) a generic fetch of west winds developed in the Northern Gulf off Vancouver Island producing 30-35 kts west winds and seas 20 ft at 49N 148.5W aimed at the US West Coast. In the evening additional 30-35 kt west winds persisted in the same area with seas 19 ft poised to impact Central Canada at 50N 138W aimed east. On Mon AM (12/8) 30-35 kt west winds continued well off Vancouver Island with seas 20 ft at 49N 140W aimed east. In the evening fetch was pushing into Central Canada with seas fading from 25 ft at 53.25N 133.75W targeting only the Pacific Northwest and Vancouver Island.

North CA: Background swell to arrive starting Tues (12/9) building to 4.5 ft 11-12 secs later (5.0 ft). Swell peaking on Wed (12/10) at 5.1 ft @ 13 secs later (6.5 ft). Swell Direction: 300-305 degrees

Kuril Gale
A fragmented gale developed off the Kuril Islands on Wed PM (12/3) generating west winds at 40-45 kts with seas 22 ft at 41N 159E aimed east. On Thurs AM (12/4) west winds were 35-40 kts streaming off the Kurils with seas 24-25 ft at 40N 160E targeting Hawaii slightly. Fetch faded to 30-35 kts in the evening with seas fading from 25 ft at 42.5N 164E aimed east. Fetch was gone after that. Low odds of swell to result for Hawaii.

Oahu: Expect swell arrival on Tues (12/9) building to 3.4 ft @ 14 secs later (4.5 ft). Swell likely being overridden by Another Dateline Swell (see below) after that. Swell Direction: 312 degrees

Another Dateline Gale
On Fri PM (12/5) a tiny gale started developing off the Kuril Islands producing 35-40 kts west winds and seas building. The gale tracked northeast Sat AM (12/6) with 40-45 kt west winds over a tiny area and seas 23 ft at 46.5N 168E aimed southeast. In the evening fetch built in coverage with 35-40 kts northwest winds and seas 26 ft at 45.5N 171.25E aimed southeast. On Sun AM (12/7) a building fetch of 35-45 kts west-northwest winds were over the dateline with seas 26 ft at 43.75N 175E aimed east-southeast. In the evening west winds were falling southeast at 35-40 kts over an elongated area reaching from west of the dateline to almost Canada with seas 28 ft at 41.75N 178.25W aimed east. On Mon AM (12/8) 30-35 kt west winds tracked east with seas 25 ft at 43.25N 169W aimed east. Fetch was fading in the evening from 30 kts 1,200 nmiles north-northwest of Hawaii with seas fading from 23 ft at 42.5N 163.5W aimed east. The gale dissipated after that. Modest swell possible for Hawaii and the US West Coast.

Oahu: Expect swell arrival on Tues AM (12/9) building to 3.8 ft @ 13-14 secs later (5.0 ft). Swell to build on Wed (12/10) reaching 5.4 ft @ 15 secs mid-AM (8.0 ft). Swell holding on Thurs (12/11) at 5.2 ft @ 12-13 secs (6.5 ft). Swell fading on Fri (12/12) from 3.8 ft @ 11 secs (4.0 ft). Dribble on Sat (12/13) fading from 3.9 ft @ 10 secs (3.5-4.0 ft). Swell Direction: 325-330 degrees

North CA: Expect swell arrival on Thurs (12/11) building to 5.6 ft @ 13-14 secs mid-AM (7.5 ft) peaking overnight. Swell fading Fri AM (12/12) from 5.0 ft @ 14 secs early (7.0 ft). Residuals on Sat (12/13) fading from 2.8 ft @ 12-13 secs early (3.5 ft). Swell Direction: 294-295 degrees.

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

Tropical Update
No tropical activity of interest is being monitored.

California Nearshore Forecast
(North CA is defined as the area north of the Golden Gate - Central CA from Pt Conception to the Golden Gate, and Southern CA everywhere south of Pt Conception).

Tioga Pass/Pacific Crest Trail intersection forecast: Temps - Freeze Level
More locations here (scroll down to 'Resort Snow Forecasts>Central CA or North CA Caltrans & Backcountry')

Snow Models: http://www.stormsurf.com/mdls/menu_snow.html (Scroll down for Resort specific forecasts).

South Pacific

Overview
Surface Analysis
No swell producing weather systems of interest were 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

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

North Pacific

Beyond 72 hours a gale is forecast developing off the South Kuril Islands on Sun PM (12/14) with 40 kt northwest winds and seas building. On Mon AM (12/15) northwest winds to be 45-50 kts with seas 41 ft at 42N 155.25E aimed east. Fetch is to be fading in the evening from 40 kts while lifting north with seas fading from 32 ft at 45.5N 158.25E aimed east. Something to monitor.

Perhaps some sort of a gale is to be trying to organize just northwest of Hawaii on Tues AM (12/16) producing northwest winds at 35 kts and seas 20 ft at 29N 168W aimed southeast. Something to monitor.

South Pacific

Beyond 72 hours no swell producing weather systems of interest are forecast.

MJO/ENSO Forecast

La Nina Is In the Ocean - But Fading in the Atmosphere
Cool Waters Dominate NINO3.4
In April 2025 weakly warm water surged east filling the Equatorial West Pacific and built into the East Equatorial Pacific. Then in late July 2025 a cool pool emerged over the East Equatorial Pacific along with a strengthened negative PDO suggesting La Nina was returning. But the SOI held generally neutral into December suggesting the atmosphere was not coupled with the ocean to support development of a wholesale La Nina. Then in Dec a long forecasted slow and steady fading of enhanced trades took over the equatorial Pacific an is to hold for the foreseeable future. Perhaps a full return to ENSO neutral is finally setting up over the equatorial Pacific.

MJO/ENSO Discussion
The Madden Julian Oscillation (MJO) 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.And the El Nino/La Nino cycle (collectively know as ENSO - El Nino Southern Oscillation) is a less frequent (about once every 7 years) but more impactful cycle that affects world wide weather. Specifically, strong El Nino events promote storm production in the Pacific while La Nina events suppress storm production. These therefore have a significant impact on the production of swell and surf. The paragraphs below analyze the state of the MJO and ENSO in the Pacific and provide forecasts for upcoming activity (or inactivity depending on the state and interaction of these two oscillations).

Overview: In 2019 warm equatorial waters were fading, and by August a tongue of cool water was tracking west on the equator from Ecuador over the Galapagos reaching to a point nearly south of Hawaii. A bit of a recovery tried to occur during Fall of 2019, with weak warm water building in the Nino 1.2 region, but cool water held in a pool off Peru. By April 2020 a cool pool was starting to build, forming a well defined cool tongue that evolved into La Nina, with it fully developing through July 2020. That pattern continued until late Fall 2022 when trades started fading and by early 2023 multiple Kelvin Waves were in flight with significant warming developing over the East Equatorial Pacific. La Nina was dead on 3/18/2023 with El Nino apparently developing. But it was not coupled with the atmosphere as of 7/20/2023 and never really did get well coupled. There is growing suspicion the Hunga Tonga volcano eruption (1/15/2022) muted El Ninos impact. Regardless, starting in Jan 2024 the first signs of La Nina emerged as would be expected, but never developed more than Modoki status.

Rationale: A Modoki La Nina developed in the Fall/Winter of 2024-25. It faded in Summer of 2025 then started turning toward La Nina again in Aug 2025. Considering it takes 3+ months for La Nina symptoms to appear in the atmosphere after the ocean (Nino 3.4) turns solidly to a La Nina configuration, and the ocean was just starting to make clear moves towards becoming solidly La Nina in late Aug, it seems La Nina could try to build into the jetstream/atmosphere in late Fall (Dec 2025). But the models suggest a return to ENSO neutral in Jan 2025. The other consideration is the PDO also appears to be still be in the cool phase if not cold, and it seem unlikely to change in the next 6 months. The net result is a trend towards La Nina as Fall progresses. And though the models suggest ENSO neutral to weak La Nina into Winter 2025/26, the PDO will overwhelm whatever push there is towards and ENSO neutral pattern beyond, resulting in some form of La Nina for the foreseeable future. This will result in less storm activity in the Northern Hemisphere for Fall-Winter 2025-26 with less storm days and smaller fetch area resulting in smaller and less frequent winter swells. One factor that could mitigate all of this is the fact the leading edge of the low pressure bias has already moved from 125E to 150E and west anomalies are forecast to build over the equatorial West Pacific over the coming months (Fall). If this happens, which is definitely up for debate, this could add fuel to the jetstream as it moves over the West Pacific making it strong and helping to improve support for storm development over the dateline as Winter processes. Most of the Pacific could be under La Nina, but the jetstream could be trending towards El Nino. As of right now, that is more of a minority outcome rather than a certainty.
KWGA/Equatorial Surface Wind Analysis (KWGA - Kelvin Wave Generation Area - The area 5 degrees north and south of the equator from 135E to 170W - The main area for generating Kelvin Waves)
Analysis (TAO Buoys): As of (12/8) 5 day average winds were strong east over the far East equatorial Pacific and strong east over the Central Pacific and weak west over the KWGA mainly south of the equator. Anomalies were neutral over the East Pacific and neutral over the Central Pacific and weak west over the KWGA. (Note: These are 5 day average winds, versus realtime, so they lag what is happening today (by about 2.5 days).
2 Week Forecast (GFS Model): (12/9) Today modest west anomalies were filling the KWGA. The forecast indicates west anomalies mostly holding at 175E through 12/13, then collapsing with modest to strong east anomalies taking over filling the KWGA 12/14 through the end of the model run on 12/25.

Kelvin Wave Generation Area wind monitoring model: West and East

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

Subsurface Waters Temps
Today (12/9) in the far West Pacific the 29 degree isotherm was tracking east from 173E to 175E due to a slackening of trades and the Active Phase of the MJO in control there. The 28 deg isotherm line was steady at 176W. The 24 degree isotherm was steady at 121W. Warm anomalies were +3 degs in the far West Pacific at depth at the thermocline (-150m) reaching east to 160W with cooler water east of there to Ecuador with a pocket at -2 degs moving east from 105W and 140W. In all cool waters are still in control of the East Pacific but not growing due to an Active Phase of the MJO slowly pushing east over the Equatorial Pacific. The hi-res GODAS animation posted 12/4 indicates weak cool anomalies were filling the upper ocean above the thermocline (75 meters or higher) east of 165E. Down at the thermocline (-150m) cool anomalies were in control east of 155W to Ecuador (a cold water Kelvin Wave). Warm anomalies were filling the West Pacific. The GODAS animation is 1 week behind the TAO data but also is more detailed and accurately depicted since its satellite based.
Sea Level Anomalies: (12/4) Sea heights over the equatorial Pacific were negative (-0.5 cms) from Ecuador to 165W (previously 150W). -10 cms anomalies were embedded in that area on the equator from 125W to 150W with a pocket over the Galapagos. The entire East Equatorial Pacific was in a cool pattern, but it seems that some warming is occurring. Heights were weakly above normal from 175W and points west of there. The cool pool is weakly fading over equator in the East Pacific.
Upper Ocean Heat Anomaly Histogram (12/4) indicates cool anomalies were filling the equatorial Pacific from Ecuador to 150W and steady. Warm anomalies were west of 162W (previously 150W). On 7/15 we went from ENSO neutral to some flavor of weak La Nina.

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 Qualitative Analysis: (12/8) The latest images depict a clear cool pool filling the equatorial Pacific from the Galapagos to 170E with embedded cooler pockets evenly spread across that area. This looks like a weak La Nina is in control. Alternate SST Anomaly (Global Mean): Warmer anomalies were limited west of the dateline with cooler waters east of there to Ecuador.
Hi-res 7 day Trend (12/8): Temps were warming weakly from Ecuador to the dateline, stronger in the west, with some cool pockets imbedded. Temp were steady elsewhere.
Nino1.2 Daily CDAS Index Temps: (12/9) (The official OISST temps are 'corrected' to the most recent 30 year base period where this data is less aggressively corrected). Today's temps were at -0.752 and have been rising the last 2 days then falling since 12/2 but otherwise rising since 11/17.
Nino 3.4 Daily CDAS Index Temps: (12/9) Today's temps were falling at -1.017 after rising to -0.922 (12/7), rising since 11/26.
Weekly OISST Anomalies were rising at -0.5 degs (week of 12/3). Previously temps were -0.6 (11/26), -0.8 (11/19), -0.7 (11/5 & 11/12), -0.6 (10/15, 10/22 & 10/29), -0.3 (10/8), -0.5 (9/24 & 10/1), -0.4 (9/17), -0.5 (9/10), -0.3 (9/3), -0.4 (8/20 & 8/27).
Monthly Data is -0.53 Oct, -0.47 Sept, -0.36 Aug, -0.14 July -0.06 June, -0.13 May, -0.14 April, +0.01 March, -0.43 Feb, -0.73 Jan.
3 Month ONI (relative centered) 3 month period is -0.78 (ASO). -0.63 (JAS), -0.47 (JJA), -0.43 (MJJ), -0.49 AMJ, -0.52 (MAM), -0.67 (FMA), -0.89 (JFM), -1.12 (DJF), -1.07 (NDJ), -0.92 (OND).

CFSV2 Forecast for Nino3.4 Sea Surface Temp (SST) Anomalies & Current SST Anomalies

SST Anomaly Projections
CFSv2 Data (Nino3.4 Region)
Previous - Temps rose unexpectedly to +0.025 in March then faded only to -0.1 in April (far less that the -0.40 forecast) then steady at 0.00 in May-June. Temps started falling in mid-July down to -0.3 in Aug, -0.45 Sept and -0.40 in Oct.
Forecast (12/6) - Sea Surface Temp Anomalies for Nov did NOT fall nearly as hard as previously forecast (forecast was -0.95 but actual was -0.7). Temps are forecast holding at -0.70 through mid-Dec then rising to technically neutral at -0.50 early Jan, -0.30 degs mid-Jan then neutral (0.0) in Feb 2026 and building after that. The PDF Corrected forecast effectively suggests the same. It looks like we're in a weak Modoki La Nina for the Fall of '25 at worst, then turning neutral before reaching Winter proper.
IRI Consensus Plume: The Nov 19, 2025 Plume (all models) depicts temps are at -0.649. Previous projections were -0.633 and -0.623. Temps to rise to -0.533 in DJF and 0.084 in AMJ. The Dynamic model suggest temps rising to -0.529 DJF and +0.543 at the end of the model run. The Statistic model suggests temps rising to -0.538 up to -0.082 at the end of the model run. In other words, We are just barely at weak La Nina today but back to neutral in January and forecast rising slowly from there indicating ENSO Neutral this Fall and Winter.
See chart here - link.

Atmospheric Coupling (Indicating the presence of El Nino in the atmosphere driven by the ocean):
Southern Oscillation Index (SOI) (negative is good, positive bad - all but the Daily Index was a lagging indicator):
Today (12/9) the Daily Index was rising at 17,96 but otherwise had been falling since 11/24 but has been positive the rest of the past month.
The 30 day average was rising some at +3.79 after falling to 3.24 on 12/8 peaking at 17.97 on 11/23, and had been rising steadily from +14.24 a month ago.
The 90 day average was rising some at +7.04 and in weak La Nina territory rising from +7.51 a month ago peaking at +9.60 11/23.

Pacific Decadal Oscillation (Negative is bad, Positive is good)
Past Recent History: The PDO theoretically turned from a warm (positive) trend in Spring of '98 and has cool (negative) mostly since then other than turning weakly positive March 2014-June 2017. It went hard negative in 10/2021-10/2023 driven by a 3 year La Nina conditions (down to -3.13). It started rising (but still negative) 11/2023-2/2024 driven by a strong El Nino, but not enough to even get it to break positive ground (best reading at -1.33 on 2/24). It then started falling in March 2024 down to -3.54 Sept (the lowest since April 1859) and -3.81 (Oct) the lowest ever reported. But in Nov the index final rose some to -3.24 and -2.08 in Dec 2024 and -1.32 in Jan 2025.
Current Situation: The index was steady at -2.40 Oct, -2.38 Sept (and inline with average readings since Nov 2021), -3.18 Aug after falling hard in July at -4.0 (the lowest ever), -2.51 June, -1.71 May, -1.18 April, -1.12 March and -1.45 Feb 2025. Looking at the long term record, it seems likely we are stable and still in the Cool Phase of the PDO (La Nina 'like') since 5/1998 with no sign of moving to the positive/warm phase (El Nino 'like') of any meaningful duration yet. We need at least 3 months of -1.2 or higher values before one could guess that maybe the cool phase is weakening.

See imagery in the ENSO Powertool 

Local Interest
Stormsurf Video Surf Forecast for this week. See it Here
For automatic notification of forecast updates, subscribe to the Stormsurf001 YouTube channel - just click the 'Subscribe' button below the video.

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ESPN Sports Center 'Ride of a Lifetime' - The backstory of Alo Slebir's possible 100+ ft wave at Mevericks - https://www.youtube.com/watch?v=luQSYf5sKjQ

NBC News - Climate Change and Surfing: https://www.nbcnews.com/mach/science/climate-change-good-surfing-other-sports-not-so-much-ncna1017131

Mavericks & Stormsurf on HBO Sports with Bryant Gumbel https://www.youtube.com/watch?v=luQSYf5sKjQ

Pieces Featuring Stormsurf:
http://www.bloomberg.com/video/how-to-predict-the-best-surfing-waves-EsNiR~0xR5yXGOlOq2MqfA.html
http://www.cbsnews.com/videos/surfs-up-for-mavericks-invitational-in-calif/

Time Zone Converter By popular demand we've built and easy to use time convert that transposes GMT time to whatever time zone you are located. It's ion left hand column on every page on the site near the link to the swell calculator.

Surf Height-Swell Height Correlation Table