On Sunday (5/1) Northern CA surf was waist to chest high and clean. South facing breaks were chest to shoulder high. Central California was waist to chest high at the best spots. Southern CA breaks from Santa Barbara to just north of LA were waist to maybe chest high. The LA area southward into Orange County was waist to chest high. Southward to San Diego waves were waist to chest high with maybe some bigger sets early. The North Shore of Oahu was starting to come on with a new swell building into the head high+ range. The South Shore was chest to head high. The East Shore was maybe up to waist high.
South swell dominates with Hawaii and California getting fun sized surf from 2 different sources. California swell is coming from a low south of the Marquesas Islands while Hawaii was getting energy from under New Zealand. And northwest swell for Hawaii was starting to build from a low that was west of the dateline. But of more interest is a larger, though not intense, low that's been tracking under Tahiti this weekend, setting up what is likely to be solid surf for late next week for both Hawaii and California. Summer is here. But waist, there still activity scheduled north of Hawaii mid-week too. North Shore likely to get some more action. See details below...
SHORT- TERM FORECAST
Current marine weather and wave analysis plus forecast conditions for the next 72 hours
On Sunday (5/1) the jetstream was zonal flowing weakly almost flat from west to east. No noteworthy features were present (animation here). Over the next 72 hours through Tuesday (5/3) the first signs of a weak trough are expected northwest of Hawaii with a second one setting up over the Kuril Islands. This is interesting given the time of year.
At the surface today three weak low pressure systems were strung across the North Pacific, one off California, one north of Hawaii, and the third over the Kurils. The Hawaiian low was modeled to have some 20-25 kt winds aimed south towards the Islands capable of producing minimal short period windswell, but that was it. The others had no winds of interest associated with them (animation here).
Last Thursday (4/28) a relatively strong but small low developed west of the dateline. Strongest winds were confirmed in the 30 kt range. The dateline low actually formed the day before well off North Japan (Wednesday AM 4/27) tracking fast towards the dateline. Winds were confirmed up to 50 kts for 16 hrs with seas building to 24 ft Wednesday PM, but it all quickly decayed late night down to 30 kts by Thursday AM (4/28) as the low lifted north and faded away. Swell from this system to hit Hawaii on Sunday AM (5/1) and continue through Monday (5/2). Little if anything to reach California. See QuikCAST's for details.
Over the next 72 hours things are to get interesting a low pressure develops in sync with the developing troughs in the upper atmosphere. We believe the documented resurgence of the Madden-Julian Oscillation (as evidenced by the strength of the Southern Oscillation Index and a Westerly Wind Burst in the Tropical Pacific) is helping to improve conditions for storm development in the North Pacific.
On Tuesday AM (5/3) a 988 mb low is to form just east of the dateline with a solid area of 35-40 kts winds expected in it's west quadrant aimed right down the 328 degree great circle path to HAwaii. Seas building to 22 ft. It is to hold for 24 hours aimed much like before, with lesser energy pushing a bit south of the 287 degree path to North California. Through Thursday (5/5) this system is to start lifting northeast into the Gulf of Alaska with winds dropping to 30 kts and seas down to 16-18 ft, then fading out by evening. A solid bit of swell looks possible again for Hawaii's north shores starting late Friday (5/6) and continuing into Saturday (5/7) with period in the 13 sec range. Maybe some reaching California this time too.
Yet another low is expected behind (See Long-Term forecast).
More model data here
On Sunday (5/1) in the South Pacific a split jet pattern continued to dominate the upper levels of the atmosphere, hampering storm development. Most energy was traveling in the northern branch with winds 140 kts south of Tahiti while the southern branch appearing cut off from any solid energy (animation here). Over the next 72 hours through Tuesday (5/3) the pattern is to get even more pronounced, with the two branches tracking across the South Pacific on nearly parallel paths. This is not supportive of storm development.
At the surface today the storm that has generated Swell #1S is still circulating south of Tahiti (see details below). No other swell producing systems were present (animation here). Over the next 72 hours no swell producing systems are forecast as the split jetstream pattern starts really putting a damper on the storm track.
More model data here
First New Zealand Pulse
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 is moving towards California starting 10.4 days out (Monday PM 5/2) with sideband energy already hitting Hawaii after 8 days of travel (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. See QuikCAST's for details.
Storm #1S - New Zealand/Tahiti Storm
On Tuesday PM (4/26) a new low pushed under New Zealand with pressure at 972 mbs while high pressure at 1028 mbs held over the Tasman Sea. The difference in pressure produced fetch of 40-50 kt southwest winds confirmed near 56S 162E. Seas were modeled at 29-30 ft centered near 58S 153E.
By Wednesday AM (4/27) the low continued east turning the fetch angle to the northeast. But the fetch stretched and lost momentum, with winds confirmed down to 35-40 kts aimed northeast up the great circle tracks to Hawaii and California. Seas remained in the 29 ft range at 56S 165E. By evening things started to consolidate better on the east side of New Zealand. A solid fetch of 40 to near 50 kts was confirmed at 44S 173W aimed northeast up the 217 degree path to California and 190 degree path to Hawaii. Seas had faded but then started to rebound.
On Thursday AM (4/28) the low held near 970 mbs with 40-50 kts southwest winds aimed like before, just a bit more to the east. Seas were modeled in the 27 ft range near 43S 168W. In the evening the system backed off some with winds confirmed at 40-45 kts centered at 45S 165W aimed northeast. Seas were modeled at 28-29 ft near 40S 170W. The gale was sitting in a hole between the two branches of the jetstream with not enough energy aloft to enable it to do much.
On Friday (4/29) AM winds were confirmed at 35-40 kts over a small area centered at 41S 163 aimed northeast with seas down to 26 ft at 35S 165W. This same scenario continued through Saturday night (4/30) a the gale drifted slowly east-northeast traveling on the 40S line with 30-40 kt fetch and 28 ft seas aimed continuously northeast. This system was starting to fade on Sunday (5/1) AM with winds confirmed down to 30 kts with no seas of interest to be left by Monday AM (5/2).
Of most interest was not this systems strength, but it's position very far to the north (40S) and it's long life. It was essentially a cut-off low, not know for being great swell producers. But it's position cut alot of travel distance out of the swell moving towards Tahiti, California and Hawaii, 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 winds 15 kts as the peak of the swell arrives Saturday AM but holding in the 10 kts range through Wednesday 5/4. Trades returning on Thursday (5/5).
But California and Hawaii to see some solid size from this system with Hawaii doing especially well.This system is the first significant class storm of the summer 2005 season mainly because of it's projected impact on Tahiti and Hawaii.
Hawaii: Expect swell arrival starting Wednesday (5/4) before sunrise with period at 17-18 secs and swell building to 3.6 ft @ 16 secs by sunset (5-6 ft faces with sets to 7 ft). On Thursday AM (5/5) swell to peak at 5 ft @ 15 secs (7-8 ft faces with sets near double overhead). Biggest early. On Friday (5/6) swell expected at 4.3 ft @ 13-14 secs (5-6 ft faces), dropping slowly through the day. Continued but fading swell expected on Saturday (5/7) with swell initially 3 ft @ 12-13 secs and fading (3-4 ft faces, bigger at best breaks). Swell Direction: 188-192 degrees
South California: Expect swell arrival starting Friday (5/6) with period 18 secs. Swell building to 1 ft @ 17 secs near dark (2 ft faces). Swell to become much more noticeable on Saturday (5/7) with swell building through the day to 2.6 ft @ 15-16 secs by sunset (3-4 ft faces with 5 ft sets). Swell to peak on Sunday (5/8) with swell 3.3-3.6 ft @ 15 secs early (5-6 ft faces with occasional 7 ft sets). Swell Direction: 213-217 degrees
North California: Expect swell arrival starting Friday (5/6) with period 18-19 secs. Swell building to 1 ft @ 18 secs near dark (2 ft faces). Swell to become much more noticeable on Saturday (5/7) with swell building through the day to 2.6 ft @ 16 secs by sunset (3-4 ft faces with 5 ft sets). Swell to peak on Sunday (5/8) with swell 3.3-3.6 ft @ 15 secs mid-day (5-6 ft faces with occasional 7 ft sets). Swell Direction: 210-213 degrees
California Offshore Forecast
Sunday mornings local charts (5/1) depicted weak high pressure at 1018 mbs just southwest of San Diego and nestled along the US west up to southern British Columbia. A weak 1010 mb low was 700 nmiles west of San Francisco pushing east and fading. It is to be deflected north by building high pressure along our coast. More low pressure is forecast to try and push towards the coast, but high pressure is to also deflect those systems to the north and away from the state.
Today's infrared satellite imagery depicted no real clouds near California. Even the low off the coast was barely visible. QuikSCAT imagery was not available . No Southern CA data available either. Buoy and nearshore reports indicated calm winds with seas 3 ft @ 14-15 secs. In Southern CA winds were northeast at 4 kts with seas 3 ft @ 14 secs.
The 5 Day local overview looks like this:
- On Monday (5/2) calm winds early building northwest 15 kts all locations.
- On Tuesday (5/3) light northwest winds early but building to 15-20 kts all locations in the afternoon.
- On Wednesday (5/4) northwest winds early 5-10 kts building to 10-15 kts in the afternoon all locations but up to 20 kts near Pt Conception and over the Channel Islands.
- On Thursday (5/5) northwest winds early 5-10 kts building to 10-15 kts in the afternoon all locations but up to 20 kts near Pt Conception and over the Channel Islands.
- On Friday (5/6) northwest winds early 5-10 kts building to 10-15 kts in the afternoon all locations but up to 20 kts near Pt Conception and over the Channel Islands.
See QuikCAST's for swell details.
Marine weather and forecast conditions 3-10 days into the future
Sundays upper level models (5/1) indicate that beyond 72 hours out two relatively prominent troughs are to develop with a ridge in between, all working their way east. By next Saturday (5/7) the ridge is to be north of Hawaii with the first trough just off the California coast and the other over the dateline. This looks most encouraging and is to be supportive of gale development at the surface.
At the surface a second large low is forecast to develop west of North Japan on Thursday (5/5) with pressure at 992 mbs. By Friday (5/6) pressure is to drop to 984 mbs with winds about 35 kts aimed well at Hawaii. Seas building to 17 ft. The low is forecast to track east-northeast reaching the dateline on Saturday (5/7) with 30-35 kt winds still aimed at the Islands. Seas building to 20 ft. Looks like another northwest 13 sec period swell could be generated focused on Hawaii.
Sundays upper level models (5/1) indicated that beyond 72 hours out the split jetstream pattern that has dominated the South Pacific is to continue with no change forecast. No indications of any large scale storm development.
At the surface the cutoff low south of Tahiti is to slowly fade out. Two storms are to track quickly under New Zealand heading east, right on the edge of the Ross Ice Shelf. Most fetch in these storms is to be aimed due east is not a little southeast towards Antarctica, so not much swell is expected to radiate 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 time 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 produced 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 continuing in the -10 to -20 range till 4/30). The MJO has firing up again with a confirmed Westerly Wind Burst over the far West Tropical Pacific. Though we had said this was not going to have any affect on producing North Pacific storms, it looks like 2 gales are not of the forecast charts, likely the direct result of the latest MJO activity. This 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...
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