SNN BIG PICTURE: Friday eve 7/13/18
NPAC: Same ole. The Jet is about as weak as it gets over a 7-day period with 50-90kts, mostly unconsolidated from the Kurils over to the Central Aleutians. Our strong ‘pair’ of 1030-1040mb Summer Highs seem to be staying put. They pump some fun windswell this weekend.
Recent-Current: For about 10 days we had some fun NE wrap Eg last Saturday reached 4’! All thanks to local and upstream NE trades plus the remnants of Tropical Storm Fabio. But the last few days it’s been weaker and weaker with mostly 0-1’ surf wrapping from the Windward side.
Not Next: Tho’ there is marginal Gale Low spinning ENE off the Kurils W-F the 11-13th, it’s just not enough to go 2500 miles. WW3 hints at ½’ of NW swell at 11 seconds Tuesday the 17th for a couple days. This would mean 0-1’ surf.
Last: Then there’s nothing popping up on the models for 10 days out.
SPAC: It’s been a good summer so far and it’s going to get better Midweek and again toward the end of next week. The Jet continues supplying plenty of energy at the surface from the Taz to SE of NZL & far South of French Polynesia. The strong Northern branch can help feed the Southern branch as it tips NE and tries to merge w/t North branch. This will help to ‘steer’ surface Lows our way and keep us busy over 2 weeks out.
Recent/current: Some small but fun straight South swell at 13-14 sec is bringing us mostly waist and a few chest high sets. The High pressures are creating brisk off to side offshore NE to ENE trades. This week was nothing to brag about for sure but there IS swell in the water. The source was the 4th of July: a big storm far SE of New Z merging with another Low further North into last Friday. This did bring us some small SSW with 18 sec forerunners Wednesday noonish; we hoped for some solid 3’ surf at 15 sec Thursday into Friday. Only Sandys saw 3′ as it was ‘straight in’. Most spots hit 2’ to 2.5’ or chest high sets.
Next: A nice looking Taz storm’s 40kt fetch hugging Australia’s East coast is long and moves East into the Taz by Sunday the 8th. We should expect 2’ forerunners midday Sunday but very inconsistent. By late Sunday and into Monday we could get 2.5’ or chest and even a few head high sets at 16 sec. It’ll fade Tuesday thru Wednesday. This Taz Low moves across New Z and is greeted by another Low to the SE…The Fetch gets off the East coast which is a zone more optimal for Hawaii SSW swells.
Next x3: So, this really nice 45kt fetch is streaming NE tightly up against the NZL coast by Tuesday the 10th.
She’s followed closely by a more compact sibling Low with 55kt pockets Wednesday. The track is pretty zonal so the fetch will cross in & out our window faster limiting the size. However, the second low gets to ‘grab’ the seas from the first Low and push ’em higher. Both storms pump up some long lasting long period SSW swell starting with the 1st swell’s forerunners of 1’ swell at 16 sec later Tuesday the 17th. Surf should build to near 3’ end of the day and near its peak 2-3’+ (hopefully 4′ due to the long periods of SSW #2) Wednesday.
Again, the second system should get bigger because she gets to ride on the aggravated seas of the first storm.
The 3rd and final Storm of this series nails up to 30′ seas and will lead to Head high plus’ surf Thursday the 19th. SSW forerunners will be 18 sec due to the high storm force gales. Waves should reach 3’ solid at 16 sec later at top spots Friday the 20th should hit 4’ solid into Saturday 21st. WW3 may be overcalling as the system seem to be tracking ENE or a hair too zonal- West to East- to maximize the swells for us.
Yet another powerful storm far ESE of New Z tracks ENE acting upon the seas of the prior Low and sees up to 30′ seas. These storms point just on the edge of the Hawaii swell window which is South of Tahiti. A portion of these events will be ‘sideband’ swell. The fetch merges with prior Low’s energy to the NE creating a Long-wide fetch 800 of miles off New Z. Monday 7/16 sees another reinforcing fetch 1200 miles away from New Z. So, we can expect a long run of multiple overhead SSW-South-SSE swells for at least a week or thru Wednesday the 25th.
Next x2 in this series: Watch 2-4′ South at 16 sec Friday the 20th all the way through the weekend. Saturday could reach 5′.
Last: the surf machine shuts down for 4-5 days between Wed the 18-Sunday,22nd. Tho’ there’s some zonal storms in the Taz they don’t look like they’ll make it up to us.
Windward Shores: Though Friday was below seasonal averages at 2′ it is coming up a notch this weekend brings us back to ‘normal’. Plus, there’s an area of upper Low pressure moving our way SE of us moving west which will lead to some instability in weather.
Recent-current: This week Makapu’u has been up to 3′ and down to 2’… today it was 2’. The uptick this weekend comes from Fresher Trades upstream & will lead to 3′ surf again thru the weekend and into the workweek. Minor variations after that. Trades are NE and fresh out over a week. Also, off California, a Low pressure pushes out some longer period NE swell for Monday but not likely much more than the 3′ Local Trade swell.
Tropics: No swell of interest for the Islands.
Note: Long-range forecasts known to be subject to pearling without recovery.
NWS criteria for High Surf Advisories (first number) & Warnings (second number).
All surf height observations & forecasts are for full ‘face’ surf height, or ‘trough to the crest’ of the wave.
Advisory and Warning Criteria Shoreline or Location
North-Facing Shores 15 Feet and 25 Feet
West-Facing Shores – Remaining Islands 12 Feet and 20 Feet
West-Facing Shores – Big Island 8 Feet and 12 Feet
South-Facing Shores 8 Feet and 15 Feet
East-Facing Shores 8 Feet and 15 Feet
Links: Get the latest Central Pac Hawaii go HERE
Terms: split Jetstream
Notes: Spectral density graph in the SNN Buoy Page GO HERE shows slivers of forerunners that initial text readings of new swells which often do not ‘show’ till later on written/text buoy updates. Also, note the vertical graph is not ‘wave height’ rather its a measure of wave energy in hertz (frequency or cycles/sec) for the whole ‘band’ (the distribution of power/period in the total wave energy field/spectrum). For the SNN Buoys ‘per shore’ arrangement GO HERE