Waves, Winds, Weather compliments of Cholos
Your exclusive Observations for Easter Sunday April 20th at 7am update
Clouds and light rain with windy NE Trades filling 15-30. Small Craft Advrys up for all waters. Small 0.5 High tide 8am dropping out to 0.0 at 115pm.
Quote of the Week "I need to feel it as an education to put myself in the zone" Pete Mel on Mavericks Invitational 2014.
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 20, 2014 3:30 AM HST
Trade winds will increase today and tonight, then remain strong on Monday, before dropping back to moderate levels by midweek. Showers will continue to focus across windward and mauka areas, with showers spilling over into some leeward areas as well.
Radar loops indicate increased shower activity moving quickly westward across the state during the past few hours, but rain gauges show generally light accumulations over windward areas. The 12Z soundings show the inversion based between 5500 and 8000 feet, with winds around 850 mb (just below the inversion) increasing to 23-27 knots at Lihue. Satellite imagery continues to show abundant mid/high level cloudiness streaming northward across the region, to the east of a mid/upper level trough centered several hundred miles to the southwest. At the surface, a 1031 mb high is centered about 950 miles north of Kauai and is building eastward.
The primary weather concern through the short term is the potential for gusty advisory level trade winds, as strong high pressure passes by to the north of the state. The 00Z uh-wrf run continues to suggest that the strongest winds are likely to occur tonight and Monday, with 925 mb winds increasing to 35 to 40 knots in some areas. Model soundings do not show quite as strong an inversion as one would ideally like to see in order to maximize wind production at the surface, but still think that some of the typically favored downslope areas will receive at least minimal advisory conditions at times especially tonight and Monday. Earlier pushed back the start time of the wind advisory to 10 am this morning, and will not make any further changes at this point. See the latest advisory product for details on areas most likely to be affected by this event.
Otherwise, mimic-tpw satellite imagery and model data continue to suggest that an area of somewhat enhanced low level moisture will continue moving westward into the state this morning. Would expect this additional moisture within the building trade flow to support increased shower activity across windward and mauka areas, with some spillover into leeward sections.
Strong trades will prevail tonight and Monday as the high passes to our north, then trades should fall back to moderate levels on Tuesday with the high moving further away to the northeast. The other player in our weather during the early to mid week period will be a slow moving mid/upper trough to the southwest of the state. Guidance is a bit more emphatic with maintaining this feature in the mid levels (500 mb) than it was previously, but shows basically no reflection in the lower levels with a distinct dry layer maintained between the moisture aloft and the moist trade flow at low levels. At this point it still appears that there will be little impact from this feature on sensible weather aside from continued bouts of mid/high cloudiness, but this is something to keep an eye on through the next few days. Barring any surprises, expect showers to continue primarily across the typical windward and mauka areas through midweek, with some spillover into leeward due to the strength of the trades.
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|