Waves, Winds, Weather compliments of Diamond Head Surfboards
Your exclusive Observations for Wednesday April 23 at 630am update
Partly Cloudy (50% leeward and 80% Windward) and ENE Trades filling 15-30mph. Small Craft Advrys for all HI Waters. Minus Low at 7am pushes to a 1.2' High tide 130pm dropping out to 0.2 at 630pm.
John John Florence on his perfect 10 from Sunday's heat in the 4th round.Quote of the Week...."it was scary to come up against those Kelly (Slater) and Gabriel (Medina),” “I got that first wave and forgot about the nerves. I took off, I saw the section coming and just flew to the air, the wind caught and spun me around perfectly".
Wake up call from Sandy's at 630am Wednesday. 3' sweet and solid. Mahalo Eric!
THE WHERE, WHEN & WHY OF HAWAII’S WAVES & WEATHER: A VIDEO PRESENTATION BY SNN
Winds Statewide in a glance ...just go HERE(this link is also the 4th drop down under weather)
Apr 24, 2014 4:00 AM HST
Breezy and gusty trade winds will strengthen gradually into Friday, and then diminish from Sunday into next week. A moister air mass will bring more showers around Friday, but otherwise rainfall will be light, and focused mainly over windward slopes, though the wind will carry some showers leeward before they dissipate.
Surface observations around the main Hawaiian islands reported moderate trade winds blowing, while pressure trends suggested little change through the short run. Cloud cover upwind of the state was fairly typical overall, with an arc of more extensive low clouds affecting mainly Kauai, but spreading south toward Oahu and Maui county. Most precipitation over land remained limited to windward slopes, where it received support from orographic forcing. Three-hour accumulation followed the cloud trends.
Aloft, weak troughing to the southwest moved further away from the islands, while broad ridging expanded over the state from the north northwest. Guidance predicted this mid-level ridge to persist through about Saturday, providing substantial support to the subtropical ridge at the surface to the northeast. Increasing wind speeds may approach the criterion for a wind advisory around Friday. Local stability also should build with time, but the full influence of the ridge had not yet begun to take effect, leaving the inversion higher than usual for the time being.
Dry trade-wind conditions will prevail through most of the forecast period. However, orographic forcing will continue to squeeze out at least a little rain over windward slopes, especially from Friday into Friday night, when most solutions predicted a somewhat moister air mass to pass.
From late Sunday into the early part of next week, the ridge aloft will shift quite far east, limiting its influence locally. Some models hinted that the old mid-level low may return from the west as an open, if shallow, trough on a broader and deeper trough approaching from the north northwest. This late in the season, the deeper trough will be very unlikely to have much local effect, but the shallower one may be able to weaken the subtropical ridge, and thus the trade winds, through this period. By the time that the surface front associated with the deeper trough arrives around Wednesday, it should be limited to little more than a slight wind shift, and a bit of converged moisture supporting the windward showers.
More typical trade-wind conditions will return through the second half of next week as another mid-level ridge builds in from the west.
A small craft advisory /sca/ remained in effect for all waters in anticipation of strengthening winds and building combined seas through Friday afternoon, but may be reduced in area to the typically windy waters around the Big Island and Maui on Saturday night or Sunday. The northeasterly winds will reach their minimum speeds late Sunday or Monday, and then increase again by the middle of next week.
The persistent trade winds will build seas, producing rough surf near the advisory level along east-facing shores by Friday. The increasing seas also will contribute to the need for an expanded SCA. Seas will diminish with the winds late Saturday and Sunday.
A northwest swell that build overnight will produce significant wave heights just below the north-shore advisory criterion on the smaller islands today. The swell will drop Friday and Saturday, but a small reinforcing northwest swell may arrive late Sunday into Tuesday.
South-facing shores have been receiving some swell energy from the southwest. This swell will fade on Friday, but small swell from the south southeast may arrive over the weekend.
BIG SURF PICTURE 4/12/14 Saturday update
The Jet has a 150mph trough inbetween Japan and HI at 30-40N latitude or 600-1200 miles north of us. There's lotsa of broad weak Jet winds from the dateline to over Hawaii thus the wetter weather. A strong High bounces the Jet up and over HI Sunday into next week. Also a new trough moves our way of Japan again Monday allowing for slight potential for continued storm development. By Friday the 18th its very weak tho' extended across the NPAC to the west coast. Hinting of a long term quite period.
Currently, we have a nice sized high surf advsry level 15 second NW reaching heights of solid 8' or triple overhead for Pipe and Sunset. Winds are NE sideshore but hey its got power. The source of Saturday's peaking event was a broad gale near the Kurils last Sunday moving east making for 28' seas. This swell will drop a lot to about 3-4' maybe 5' Sunday morning.
Next: A Low pops on the charts Friday 4/11 near the Kurils Is again but this ones smaller and farther away (2200 miles). Winds are stronger but wont make up for the afore mentioned factors. She'll build Wed nite the 16th peaking 5-7' Thursday from the WNW.
Last: The Jet goes zonal mid April with quick eastbound Lows bring short lived smaller spring like/small NNW surf next Saturday. Keep you posted. Better shot of NW possible on Thursday the 24th.
Long range models love to fantasize. Meaning they run 'hot' making promises they can't always keep.
SPAC: The Jet is weak and zonal or west to east from Sat to Wed. the 16th when a weak NE flow shows esp by Friday-Sunday. The main push for swell will move out of our window.
Currently: Distant past sources make for background 14 seconds with just 1' swell...this leads to 2' surf for most spots thru next weekend. Below average.
Next: If long range outlook stands the test of time we'll get a 2' SSW Thursday the 24th from a marginal NE bound Low Thursday the 17th.
Last: Friday the 18th shows a large Low far south of Tahiti ramping to 35' seas by Saturday as it tracks ENE out of our window; maybe some long period 2-3' sideband SSE surf Saturday the 26th.
The Windward side see’s small 2' ENE wind swell at 8 seconds ramping to 2-4' this weekend esp Sunday into Monday the 14th from increasing trades from the building strong High. Chance of high surf advsy surf. Model hint of Trade fetch weakening Tuesday thus a weakeing windwave swell esp by Wednesday. Typical spring.
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.
|North-Facing Shores||15 Feet (8')||25 Feet|
|West-Facing Shores - Big Island||8 Feet (4'+)||12 Feet|
|West-Facing Shores - Remaining Islands||12 Feet (7')||20 Feet|
|South-Facing Shores||8 Feet (4'+)||15 Feet|
|East-Facing Shores||8 Feet (4'+)||15 Feet|