THE LATEST IN DEPTH VIDEO PRESENTATION OF HAWAII'S WAVES,WINDS & WEATHER FROM SURF NEWS NETWORK & SPONSORED BY HAWAIIAN SOUTH SHORE

Winds Statewide in a glance ...just go HERE (this link is also the 4th drop down under weather)

May 23, 2013 6:45 AM HST

Marine
The current south swell will keep lowering, and surf along south shores will remain below advisory levels for the next several days. The northwest swell will gradually diminish through the weekend.

Trade winds will strengthen through the week, and are expected to reach small craft advisory levels over the windier locations near Maui county and the Big Island by Friday night.

Watches/Warnings/Advisories
Wind advisory until 6 pm HST this evening for Big Island summits.

Synopsis
A pair of surface troughs to the north will keep winds light today. That will allow sea breezes to produce clouds and showers over interior areas this afternoon. Trade winds will spread over the area tonight as a surface ridge builds north of the area. Trade winds will persist through the coming week. The trades will bring showers to mainly windward areas. A trough aloft may make these showers fairly active.

Discussion
An upper lvl trough is being observed on wv satellite data, located some 750 miles NE of the main Hawaiian islands. Sfc analyses show two decaying troughs, one just N of the Big Island and the other lingering around 400 miles N of Kauai. Meanwhile, a broad sfc high remains centered far to the NE of the main Hawaiian islands.

The sfc troughs will continue to break down today and allow for an onset of returning trade winds across the islands, but not quick enough in order to override sea breeze circulations this afternoon. Therefore, there should be one more round of convection today with showers favoring interior and mountain areas as sea breezes push inland.

The influence of the upper lvl trough is still keeping tight gradients at the mid/upper lvls, with strong winds around 14-15 kft expected to continue today. Thus, the wind advisory for the Big Island summits is now valid through 6 pm HST this evening, and it may be extended if necessary.

The sfc high NE of the islands will strengthen during the next couple of days. This will bring a trade wind weather regime across the aloha state, starting tonight and becoming moderate to fresh through the end of the week. Global models remain in fair agreement with this overall scenario for the long term forecast, with upstream moisture feeding windward and mauka showers as the trades establish

BIG SURF PICTURE Wednesday 5/13/13 

NPAC  Looking above average from Saturday through next Saturday.

Currently: lingering N swell at up to 0-2' for Laniakea and 1.5' for other spots.

Next: A marginal gale floats east off the Kurils all week crossing the dateline Wednesday up above 40 degrees north or about 1000 miles away. We can expect a fun spring time 11 second, 2-3+ NW filling Saturday and holding 3' Sunday before fading next week.

Last: Models keep supporting a unseasonal Low off Japan tonight which will stall then track ENE about 2000 miles away; she fades near the dateline Sunday but not before pushing out some 14 second NW swell with easy 4-6' surf Wednesday. We may give it an upgrade as buoy forecast currently show 6' 15 seconds which is enough for "almost" 8' at focal reefs like Sunset.

Long range fantasys need focus.

(See HERE)

SPAC  It has been a really good spring with half a dozen swells aready but now it's really 'up there' in the ratings.

Currently: its cranking 4-6 from the S to SSW with higher sets and buoys 5' 17 seconds. So some reefs hit 8' today.

Buoys popped Wednesday nite at  20 sec forerunners from a rare run of SSW to S swell. Ascat wind measurements confirm a big storm with a good ''following fetch' on its NE track up and then out from the east coast of NZL this past Thursday-Saturday. Seas are about 35-40' and winds were solid 45kts over a wide area. We'll see our 1st of 4 advisory SSW swells filling late Thursday to solid 4' and even 6' at 'select reefs; a peak of 5' open ocean 16-18 second event (country hits 8' with this kind of reading). Our guesstimate peak on Friday afternoon is 4-7' surf (2.5 times overhead) into Saturday and even Sunday since the system stalled.

Next: This giant storm stalls or occludes over the weekend of the 18th more to our South allowing for another shot of lasting South swell in the 3-6' range but with 15 seconds.

Next: Another Low has its fetch off to the SE of NZL Monday-Tuesday 5/14 pushing up some solid 3-5+' South by Monday-Tuesday 5/20-21. She'll be a notch smaller than the 1st pulses.

Next: The final shot from this 4 swell series is filling late Tuesday peaking Wednesday at 3-5' then down 2-4' Thursday....

Last: we go into a relatively quite period till further notice. But models have a more background 1-3' South surf  with 15 seconds (2' open ocean) from Friday afternoon into Monday; this is from more distant zonal storms.

East Shores: Strong 1028 mb High to out NE fixes out weather and waves. Up to 3' is the trend from the fresh NE winds and N swell.

Tropics: This past Thursday model have a storm moving west under Baja . She dies off this Sunday as soon as she hits cooler water.

FETCH: Often called the fetch length, is a term for the length of water or distance over which a given wind direction has blown. Fetch length along with the wind speed (or strength) determines the size of waves produced. The longer the fetch length and the faster the wind speed, the larger and stronger the wave will be and vice versa.
CAPTURED or FOLLOWING FETCH: Not only does the fetch length determine the power and energy of the wave. Additionally, if the winds/fetch are blowing in the same direction as during the wave's or storm's lifetime, the wave will in turn be even stronger. The fetch is related to the orbit of the wave and track of the storm.The longer the wind drags along the sea the more energy the wave will have. This can be seen not just in vertical height measurement but in wave period (the measurement of waves through time).
WAVES PERIOD:Time, in seconds, between the passage of consecutive wave crests past a fixed point. In general the longer the period the bigger the wave. Windswell or 'close interval' swells are under 10 seconds. Big 'ground swells' are 17-20+ seconds (note: a 20+ second swell needs storm force 50+kt winds blowing over a 1500 mile fetch to be fully developed' into 20-25' beasts; these 20 second waves can be felt 1000 feet down!). This is why they jack so much more, pulling large amounts of H2O off the outer reefs.

More generic marine definitions click this link  http://www.prh.noaa.gov/hnl/pages/marinedef.php

....All surf height observations and forecasts are for the full face surf height, from the trough to the crest of the wave.