Big Picture

BIG PICTURE: Update for Friday, Aug 18

NPAC: Main deal still: our persistent summer High pressure and wrapping windswell. The Jet is still very weak, disorganized with no chance of ground swell from the typical WPAC to Central Pac zones.

#1 Recently and currently: It’s been rideable this week but just off and on waist high at Laniakea etc. Tuesday got a ramp of wind swell from upstream and long-term local trades. Thursday saw thigh high and Friday see’s barely waist highs. The weekend will possibly see longer period wind swell from tropical disturbance far ESE of Big Is. But nothing over 3’ for Windward and maybe 2’ for the country.

#2 Next and long-range: As far as NW swells…nothing out 10 days as of Friday 18th.
SPAC: The JETSTREAM: still has the North branch w/t most the energy esp over the Taz. But we like the South Branch to crank and its shut down for nearly 10 days. The south branch is super weak and zonal or west to east. No ‘significant’ surf is expected for the rest of August. But we will see continued average waist to chest high with a few head high events off and on.

#1 Recent + Today: We had a 15 sec South hit the buoys at early this week. Sets saw a few 3’ but with long waits and the event veered SSE. We now have another SSE at about 14-16 secs with some 3’ sets for ‘town’. Low under Tahiti Thursday 10th popped our buoys to 17 sec earlier Thursday. This SSE filled late Thursday peaking Friday. Sandy’s is magnifying up to 4’ easy today. This will fade over the weekend. The source for the current episode was the same Low pushing up the prior South. The storm stalled SE of Tahiti last Thursday and thus the 17sec forerunner Thursday and 3’ sets Friday.

#2 Next + LongRange: We’re monitoring the Taz Sea for a possible SW next Friday-Sunday. It wont likely be over 2’. We also saw some fetch ESE of Tahiti midmonth which may add some small SE swell next Tuesday-Friday. We must wait till next weekend to see if anything ‘real’ pops up down under…. meaning there’s nothing in the 14-day outlook outside of the swells above.

TRADE SWELL
Trades swell finally bounced back to seasonal averages this week of 1-3 at 8 sec along most Windward outer reefs + shore pound. This was thanks to the High pressure’s upstream trades though this slightly longer period won’t last much beyond Wednesday. We’re now back into below averages thanks to lighter Trades into this Weekend.

TROPICS: Hurricane season began June 1st-Nov 30th.
A new storm is here:

Tropical Depression 13-E as of 800 AM PDT Fri Aug 18 shows deep convection associated with the disturbance located over the open eastern Pacific Ocean has become better organized early this
Morning. It’s too early for swell prediction.








The Central Pacific Hurricane Center outlook for the 2017 Central Pacific Hurricane Season calls for 5 to 8 tropical cyclones to either develop or cross into the Central Pacific with a 40% chance for an above-normal season, a 40% chance for a normal season, and a 20% chance for a below-normal season. An average season has 4 to 5 tropical cyclones, which include tropical depressions, tropical storms, and hurricanes.
A tropical depression forms when a low-pressure area is accompanied by thunderstorms that produce a circular wind flow with maximum sustained winds below 39 mph. An upgrade to a tropical storm occurs when cyclonic circulation becomes more organized and maximum sustained winds gust between 39 mph and 73 mph. A tropical storm is then upgraded into Category 1 hurricane status as maximum sustained winds increase to between 74 mph and 95 mph. (The highest classification in the scale, Category 5, is reserved for storms with winds exceeding 156 mph).
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Tropical cyclones go by many names around the world, and the terminology can get confusing. Once a tropical cyclone strengthens to the point where it has gale-force winds—39 mph or greater—it becomes a tropical storm. A storm that reaches tropical storm strength usually gets its own name to help us quickly identify it in forecasts and warnings. Once a tropical storm begins producing sustained winds of around 75 mph, we call the storm a typhoon in the western Pacific near Asia and a hurricane in the oceans on either side of North America.

The Central Pacific Hurricane Center outlook for the 2017 Central Pacific Hurricane Season calls for 5 to 8 tropical cyclones to either develop or cross into the Central Pacific with a 40% chance for an above-normal season, a 40% chance for a normal season, and a 20% chance for a below-normal season. An average season has 4 to 5 tropical cyclones, which include tropical depressions, tropical storms, and hurricanes.
Tropical depression forms when a low-pressure area is accompanied by thunderstorms that produce a circular wind flow with maximum sustained winds below 39 mph. An upgrade to a tropical storm occurs when cyclonic circulation becomes more organized and maximum sustained winds gust between 39 mph and 73 mph. A tropical storm is then upgraded to Category 1 hurricane status as maximum sustained winds increase to between 74 mph and 95 mph. (The highest classification in the scale, Category 5, is reserved for storms with winds exceeding 156 mph).
.
Tropical cyclones go by many names around the world, and the terminology can get confusing. Once a tropical cyclone strengthens to the point where it has gale-force winds—39 mph or greater—it becomes a tropical storm. A storm that reaches tropical storm strength usually gets its own name to help us quickly identify it in forecasts and warnings. Once a tropical storm begins producing sustained winds of around 75 mph, we call the storm a typhoon in the western Pacific near Asia and a hurricane in the oceans on either side of North America. A “typhoon” and a “hurricane” are the same kind of storm, they just go by different names…it’s only a matter of geography.


A tropical depression forms when a low-pressure area is accompanied by thunderstorms that produce a circular wind flow with maximum sustained winds below 39 mph. An upgrade to a tropical storm occurs when cyclonic circulation becomes more organized and maximum sustained winds gust between 39 mph and 73 mph. A tropical storm is then upgraded into Category 1 hurricane status as maximum sustained winds increase to between 74 mph and 95 mph. (The highest classification in the scale, Category 5, is reserved for storms with winds exceeding 156 mph).
Right now we have Tropical Storm (TS) Nanmadol approximately 163 nm east-northeast of Taipei,
Taiwan, and had tracked at 14 knots over the past six hours (As of 3pm Monday 7/3. Maximum sustained surface winds were estimated at 50 knots gusting to 65 knots. We are not expecting swell from this region.

There are 3 disturbances in the East North Pac…1st, by Mexico 625 miles south of the tip of Baja. The other 2 have 0 chance of becoming more than a depression.

Tropical cyclones go by many names around the world, and the terminology can get confusing. Once a tropical cyclone strengthens to the point where it has gale-force winds—39 mph or greater—it becomes a tropical storm. A storm that reaches tropical storm strength usually gets its own name to help us quickly identify it in forecasts and warnings. Once a tropical storm begins producing sustained winds of around 75 mph, we call the storm a typhoon in the western Pacific near Asia and a hurricane in the oceans on either side of North America. A “typhoon” and a “hurricane” are the same kind of storm, they just go by different names…it’s only a matter of geography.





NWS uses the criteria below for the issuance of High Surf Advisories & Warnings in coordination with civil defense agencies & water safety organizations in Hawai`i.

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

Advisory and Warning Criteria
Location Advisory Warning
North-Facing Shores 15 Feet 25 Feet
West-Facing Shores - Big Island 8 Feet 12 Feet
West-Facing Shores - Remaining Islands 12 Feet 20 Feet
South-Facing Shores 8 Feet 15 Feet
East-Facing Shores 8 Feet 15 Feet
'Travel Time' Buoy 51101 to Waimea Buoy
Distance: 269 nautical miles (~310 miles)
Angle: 307 deg

Wave Wave Wave Depth Wave Direction (deg)----------

Period Length Speed Shallow 295, 305, 315, 325, 335, 345, 355

(s) (ft) (nm/h) (ft) Travel Time (hours)----------

10sec. 512. 15. 256. 17.3, 17.7, 17.6, 16.9, 15.7, 14.0, 11.9

12sec. 737. 18. 369. 14.5, 14.8, 14.6, 14.0, 13.0, 11.6, 9.9

14sec. 1003. 21. 502. 12.4, 12.7, 12.5, 12.0, 11.2, 10.0, 8.5

16sec. 1310. 24. 655. 10.8, ,1 1.1, 11.0, 10.5, 9.8, 8.7, 7.4

18sec. 1658. 27. 829. 9.6, 9.8, 9.8, 9.4, 8.7, 7.8, 6.6

20sec. 2047. 30. 1024. 8.7 8.9 8.8 8.4 7.8 7.0 5.9

22sec. 2477. 33. 1239. 7.9 8.1 8.0 7.7 7.1 6.3 5.4

24sec. 2948. 36. 1474. 7.2 7.4 7.3 7.0 6.5 5.8 4.9



Surf Advisory and Warning Criteria

Location/shoreline Advisory Warning
North-Facing Shores- 15 Foot faces (8' Local) 25' Foot faces (15' local)
West-Facing Shores - 12 Foot (7' local) 20 Foot (12' local)
West-Facing- Big Is. - 8 Foot (4'+ local) 12 Foot (7' local)
East-Facing Shores- 8 Foot (4'+ local) 15 Foot (8’ local)

Tropical Storm - winds 39-73 mph (34-63 kt)
Category 1 - winds 74-95 mph (64-82 kt)
Category 2 - winds 96-110 mph (83-95 kt)
Category 3 - winds 111-130 mph (96-113 kt)
Category 4 - winds 131-155 mph (114-135 kt)
Category 5 - winds 156 mph and up (135+ kt)

Please visit the Central Pacific Hurricane Center website at www.weather.gov/cphc for the most recent bulletins.

ENSO is a single climate phenomenon, it has three states, or phases. The two opposite phases, “El Niño” and “La Niña,” require certain changes in both the ocean and the atmosphere because ENSO is a coupled climate phenomenon. “Neutral” is in the middle of the continuum. The MJO (Madden-Julian Oscillation) is an eastward moving disturbance of clouds, rainfall, winds, and pressure that traverses the planet in the tropics and returns to its initial starting point in 30 to 60 days, on average, unlike ENSO which is stationary. In a nutshell, more active means more surf.

Kelvin wave (A Kelvin wave is a wave in the ocean or atmosphere that balances the Earth's Coriolis force against a topographic boundary such as a coastline, or a waveguide such as the equator. A feature of a Kelvin wave is that it is non-dispersive, i.e., the phase speed of the wave crests is equal to the group speed of the wave energy for all frequencies. This means that it retains its shape as it moves in the alongshore direction over time.)

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