PACIFIC OVERVIEW
On Tuesday (4/26) Northern CA surf was waist high. South facing breaks were waist to chest high coming from the southwest. Central California was waist high with a few chest high sets. Southern CA breaks from Santa Barbara to just north of LA were waist high. The LA area southward into Orange County was waist to chest high. Southward to San Diego waves were waist to chest high. The North Shore of Oahu was waist high.cgius. The South Shore was near flat. The East Shore was flat.
Small surf remained the norm, though a bit more southern hemi swell was pushing into California than was expected with top spots seeing chest to shoulder high surf. Small northwest swell starting to build on Oahu's North Shore with southern hemi swell scheduled for the South Shore over the weekend. A different Southern Hemi swell is also pushing north towards California for the weekend too. See details below...
SHORT- TERM FORECAST
Current marine weather and wave analysis.cgius forecast conditions for the next 72 hours
North Pacific
Overview
On Tuesday (4/26) the jetstream had a little but steep trough over the dateline with a large ridge building over the Gulf of Alaska. A weak trough was just off California (animation here). Over the next 72 hours through Friday (4/29) no significant change is forecast a ridge dominating the Gulf of Alaska with energy fading in the west. Not much to support any storm development.
At the surface today high pressure at 1028 mbs was centered over the dateline. As was indicated by the upper level models, low pressure at 984 mbs was just east of the dateline nestled up to the Aleutian Islands. It started developing Wednesday AM (4/25) and tracked quickly northeast with 35-40 kts northwest winds confirmed aimed at Hawaii but fairly far south of the great circle paths to California. Seas build to 16 ft Thursday AM aimed best at Hawaii. Weak windswell for Hawaii looks likely with some minimal energy pushing east towards California (animation here).
Over the next 72 hours another small 980 mb low is to develop well off North Japan (Wednesday AM) tracking fast towards the dateline. Winds up to 45-50 kts for a few hours, then quickly decaying to 30 kts by Thursday AM (4/28) limiting seas to 25 ft at that time just west of the dateline. Again, weak windswell potential for Hawaii with even less energy reaching California.
Also last Thursday (4/21) a 988 mb low pushed off the Kurils tracking northeast, producing a tiny fetch of 50 kt west winds that evening that quick degenerated to 40 kts on Friday into Saturday (4/23). Seas on Saturday were modeled up to 25-28 ft aimed at Hawaii, but they were fading fast by Sunday AM (4/24) as the low lifted north of the Aleutians near the dateline. Swell from this system was starting to hit the North Shore of Oahu this afternoon with even less energy still pushing east towards California and the Pacific Northwest.
More model data here
South Pacific
Overview
On Tuesday (4/26) in the South Pacific a .cgiit jet pattern remained in.cgiace over the entire area west of Tasmania into South America. This was not conducive to storm development (animation here). Over the next 72 hours through Friday (4/29) there's some indications that a decent trough will try and develop just east of New Zealand on Thursday (4/28), but it is to get cut off over the weekend and loose any energy it was developing.
At the surface today a mixed pattern of mild high and low pressure was present over the broader South Pacific, but no indications of any real storm or fetch suggested. Under Tasmania a 972 mb low was present with 45-50 kts west winds confirmed by the QuikSCAT satellite at 57S 152E aimed up the 218 degree path to California but shadowed from Hawaii by New Zealand (animation here). Over the next 72 hours this system is to slide up the eastern side of New Zealand with a consistent fetch of 40-45 kts winds aimed continuously at California up the 218 degree path and pushing well up the 195 degree path to Hawaii too, fading Friday morning (4/29). Seas expected at 28-30 ft through the period.
Current data suggests that a nice shot of fun sized swell should push north right up the great circle paths to both Hawaii and California, with Hawaii getting the most size due to it's close proximity to the fetch (minimizing swell decay). Most size likely in the 14-15 sec period bands.
More model data here
Brief Fetch
On Thursday AM (4/21) a tiny 988 mb low was developing in the northeastern reaches of the South Pacific with 40-45 kt south winds imaged at 42S 138W. It slid slowly east with pressure dropping to 984 mbs on Friday (4/22) while seas built to 29 ft over a tiny area centered at 37S 135W. This system faded late Friday into Saturday AM (4/23) with winds dropping to 35 kts or less. This system was well to the north of usual, reducing swell travel time and decay, but the fetch area was tiny with only a very limited sea generation window. There is the potential to generate a small background swell (but rideable at best South and North California breaks) coming from 190-195 degrees arriving late next week. No real fetch was aimed at Hawaii.
New Zealand Storm
On Thursday (4/21) a 956 mb low was tracking east in the deep South Pacific under New Zealand while high pressure at 1028 mbs held over the Tasman Sea. This was generating a gradient between the two with 40-45 kt west winds centered near 60S 160E. Even on Wednesday night (4/20) the QuikSCAT satellite confirmed winds of 50-55 kts over a tiny area positioned well southwest of New Zealand at 60S 148E. These winds were aimed well at California up the 213-215 degree great circle paths and moving into the Hawaiian swell window from behind the New Zealand shadow at 210 degrees. The fetch bloomed Thursday evening as pressure in the low dropped to 952 mbs while the high over the Tasman Sea increased to 1032 mbs. Winds were confirmed at 45-50 kt blowing from the west over a broad area centered at 60S 165E. They were aimed about 25 degree east of the 211 degree path to South CA and 45 degrees east of the 197 degree path to Hawaii. Seas were modeled at 29 ft centered at 60S 162E.
On Friday AM (4/22) the low pushed southeast away from the high some, and as a result the fetch started to fade down to 40-45 kts in the AM (at 59S 168E) and even less in the evening. Stronger winds at 50 kts were blowing right off the Ross Ice Shelf aimed towards California, but this was essentially and new fetch and no seas were associated with it yet. Seas in the original fetch were 35 ft (at 59S 171E) but down to 31 ft by evening (at 57S 180E).
On Saturday (4/23) the low was diving southeast over Antarctica and the fetch dissipated. No fresh seas were generated.
This was a rather small system that was short lived and positioned a long ways from both Hawaii (5107 nmiles) and California (6645 nmiles). Based on this confirmed data a small 16-17 sec period swell appears is likely for California starting 10.4 days out (Monday PM 5/2) with sideband energy moving up to Hawaii starting 8 days away (Saturday AM 4/30). But the long travel distance will ensure that swell decay and inconsistency will be major negative factors. Still, something rideable is expected. .
California Offshore Forecast
Tuesday mornings local charts (4/26) depicted high pressure at 1022 mbs centered north of Hawaii pushing north and totally blocking the Aleutian Storm Corridor. A weak 1010 mb low was 600 nmiles west of Cape Mendocino sinking southeast. this low is to push into Central California on Thursday (4/28) with a series of more weak lows following east from across the dateline. A broader and somewhat more active one is schedule for mid-next week, but that's purely a guess by the models.
Today's infrared satellite imagery depicted faint clouds associated with the low off the coast rotating around the low and pushing up the California coast. QuikSCAT imagery indicated near calm to light offshore winds along the North coasts and northwest at 5-10 kt over Central CA. Calm winds indicated in the South. Buoy and nearshore reports indicated light northwest winds with seas 3 ft @ 12 secs. In Southern CA winds were west at 6 kts with seas 3 ft @ 14 secs.
The 5 Day local overview looks like this:
- On Wednesday (4/27) south winds 5-10 kts all day North and Central as the low pushes nearer the coast. South CA to have and light northwest winds building to 10 kts in the afternoon.
- On Thursday (4/28) south winds to 10 kts all locations all day as the low pushes closer.
- On Friday (4/29) near calm winds early turning northwest 10 kts in the afternoon as the low pushes inland.
- On Saturday (4/30) light northwest winds all locations all day, but up to 15 kts off the Channel Islands in the afternoon
- On Sunday (5/1) light winds all locations all day.
See QuikCAST's for swell details.
LONG-TERM FORECAST
Marine weather and forecast conditions 3-10 days into the future
North Pacific
Tuesdays upper level models (4/26) indicate that the huge ridge over the Gulf of Alaska is to cut itself off and drift north of Alaska, leaving a weak zonal flow over the entire North Pacific. No signs of anything capable of supporting a decent storm are suggested. It's over for the season.
At the surface a weak 1000 mb low is forecast off California a week out, but that's it. No fetch capable of generating either swell or windswell is suggested.
South Pacific
Tuesdays upper level models (4/26) indicate that the .cgiit pattern is to dominate through at least next week, not supporting any large scale major storm development.
At the surface the fetch forecast just east of New Zealand is to track east and go stationary due south of Tahiti over the weekend with pressure at 980 mbs. Varying degrees of 35-40 kts winds are to be aimed due north generating 24-29 ft seas pushing towards Tahiti and California fading by early next week. Of most interest is not this systems strength, but it's position very far to the north (40S). This will cut alot of travel distance out of the swell moving towards Tahiti and California, reducing swell decay. Unfortunately Tahiti will likely be too close to the fetch, meaning the swell will be raw, and poor local winds conditions are expected (south 15 kts as the peak of the swell arrives).
Additional storm energy is to be flowing under New Zealand, but the dominant southern branch is to direct these systems into Antarctica with little energy flowing north.
Southern Oscillation Index
Also of real long-term interest is the Southern Oscillation Index. This is an indicator of developing El Nino or La Ninas. Back in February through early March it went very negative, the most it had done in over a decade for that tome of year. This was a signal that a major pulse of the Madden Julian Oscillation was in effect, and that is what produced the string of solid swells in the North Pacific at that time. It also produce a major eastward moving Kelvin Wave (warm water pool) that is about to impact the South America coast on the equator within the next week or so. These sorts of signals are indicative of El Nino.
This all faded in mid-March, but the SOI index has again dropped well into the negative range (-25 to -35 daily starting 4/13) and we suspect that the MJO is again going to fire up. This is not so much going to have any affect on producing North Pacific storms (though it might jump start the typhoon cycle in the far West Pacific) but is a second good push towards an El Nino for the coming winter. We would want to see a series of these cycles through the summer. Nothing conclusive yet, but this is much more encouraging than anything we've seen in years since the last big El Nino of 97/98.
Details to follow...
Local Interest
Big Florida Swell: A strong gale pushed off Cape Hatteras on 4/15 generating solid seas and a 70 ft rogue wave that hit a cruise ship before proceeded south to make solid waves for the Southeast US coast. Matt Kechele was there to catch it. Take a look here: http://www.stormsurf.com/page2/forecast/forecast/kechele.html
Stormsurf Weather Models Updated Again: Yes, we've been at it again this weekend getting another batch of weather models running. Global coverage is now provided for jetstream forecasts and surface pressure and winds. Zoomed in data is also available for such locations as the Mentawai Islands to Western Australia corridor, Tahiti, South America, Europe and Norwegian Sea. So now you can get local wind forecasts for these and more locations with one click. Take a look here: http://www.stormsurf.com/mdls/menu.html
WaveWatch.com - New Surf Forecast Website: Read this teaser about something new on the scene. http://surfermag.com/features/onlineexclusives/ww_qna/
Wave and Weather Models We've updated our set of Wavewatch III and GFS weather models to include the Indian Ocean and South Pacific in preparation for the coming Southern Hemi big wave surf season. Take a look here or click 'Models' on the navigation bar at the top of every page: http://www.stormsurf.com/mdls/menu.html
Ghost Tree 3/9/05: Check out the pics of Don Curry and others on Monster Swell #16 in Monterey. http://www.stormsurf.com/page2/forecast/forecast/ghost_tree.shtml
SURFRIDER Web Site: The San Mateo County Chapter of SURFRIDER can be found at: http://surfridersanmateoco.org Take a minute to visit and find out what's happening to your coast.
Surf Height-Swell Height Correlation Table
