Outlook through Tuesday December 08: a new advisory-level northwest swell will rise tonight, peak early Wednesday, and then lower gradually Thursday and Friday. A larger northwest swell is expected over the weekend bringing surf heights to low-end warning levels. Trade winds will continue to produce short-period choppy surf along east-facing shores. Surf heights are forecast heights of the face or front of waves. The surf forecast is based on the average height of the one third largest waves at the locations of the largest breakers. Some waves may be more than twice as high as the significant wave height. Expect to encounter rip currents in or near any surf zone.
HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES
Surf along north facing shores will rise to 8 to 15 feet this evening, and to 18 to 22 feet Wednesday. Surf along west facing shores will rise from 4 to 8 feet this evening to 10 to 14 feet Wednesday. Surf along east facing shores will be 4 to 7 feet through Wednesday. Surf along south facing shores will be 1 to 2 feet through Wednesday.
About Collaborative Surf
THIS COLLABORATIVE FORECAST WILL BE UPDATED MONDAY THROUGH FRIDAY AT 300 PM WHEN PAT CALDWELL IS AVAILABLE/
Collaborative Surf Discussion
Discussion: summary: Winter caliber surf during event maximums for north shores with steady E windswell. Detailed: Mid Monday on northern shores has breakers near the October to April seasonal average from 320-340 degrees at 11-15 second wave periods. Heights should lower on Tuesday with a new event building late in the day. The jet stream has maintained a position south of the Aleutians 11/23-30 with troughs not amplifying too greatly resulting in a near eastward track of surface low pressures across the breadth of the basin within 40-55°N. This is giving long-lived events with maximums above average starting out near WNW to NW then veering NNW. The low pressure track of 11/25-27 that gave the above average surf locally 11/28-29 had the tail of the fetch about 1800 nm hugging the Aleutians just east of the dateline 11/27. Buoy 51101 and 51001 WNW of Kauai shows a sharp decline in wave energy within 12-15 seconds Monday morning 11/30. This event should drop below average overnight with a continue slow decline on Tuesday from within 320-350 degrees. The next low in the series gained storm-force status east of the kuril island late Friday 11/27 and reached near the dateline Sunday. Jason satellite estimated seas near 25 feet at a location about 2000 nm away near 40°N, 170°E at 12Z 11/29, or 2 am HST Sunday. The low center is near 55°N, 160°W well to the north of Hawaii on Monday 11/30. The strongest winds of the system were not as strong and were more west to east than the low track of 11/25-27, thus local surf is expected to be lower than the weekend of 11/28-29. Long-period forerunners are due mid afternoon Tuesday from 310-320 degrees. Surf heights should build above average overnight Tuesday, with the event filled in from 310-325 degrees by dawn Wednesday. A reinforcement pulse is due Thursday. Synoptic weather charts show a jet-level, short-wave trough near the dateline just west of the parent low over the eastern Aleutians 11/29-30. At the surface an area of gales behind a SE pushing front has set up north of 40°N. Ascat shows the speeds within the gale bracket late Sunday beyond 1500 nm away. Models show the lower-end gales reaching to near 900 nm north of Hawaii pre-dawn Tuesday. Highest seas are aimed E of Hawaii. This source should keep surf heights above average with added energy from 320-340 degrees at medium wave periods of 12-15 seconds building Wednesday night, peaking Thursday morning, then slowly dropping below average by mid Friday from 330-350 degrees. Small surf is expected by Saturday as a new event builds. Models show a low pressure deepening rapidly late Tuesday with an eastward track from near Kamchatka south of the Aleutians. Central pressure is predicted to fall near 960 mb as it approaches the dateline Thursday. The most recent model runs have shown a more easterly track while west of the dateline, as opposed to model runs a few days ago that gave more ESE in track. The more easterly track has less captured so the more recent wave model runs have showed less deep water swell locally. In general, surf should climb to extra-large levels, meaning high enough for breakers on outer reefs, from 315-325 degrees by Saturday late afternoon. Models are showing a more ESE track once east of the dateline, though the highest seas would already be aimed E of Hawaii. More specific height estimates can be made as the system unfolds. Mid Monday on eastern shores has breakers above the trade windswell average from 60-90 degrees. Heights are expected to lower on Tuesday. The less amplified jet stream troughs that have been centered near 45°N across the north Pacific has allowed a zonal axis of surface high pressure to be entrenched across the basin near 30°N. The associated lows and fronts that have passed and are modelled to track N of Hawaii have not penetrated south enough to eliminate the trades. A minimum is expected locally in the trades Tuesday morning and another roughly Friday. Even at the minimum, the upstream fetch of moderate to fresh trades and the locally moderate trades should keep breakers from windswell from within 60-90 degrees at the trade windswell average during the minimums. The next high pressure cell is modelled to be north of Hawaii Wednesday, giving a local peak to trades, with the windswell maximum within mid Wednesday to mid Thursday from 50-80 degrees. Into the long range, trade windswell should be near the average 12/6-7 from 70-90 degrees. The extra-large event due 12/5 is modelled to peak overnight Saturday night from 320-340 degrees. It should remain above average into Monday 12/7 with a steady downward trend from 320-350 degrees. The next low in series is modelled to form further south east of Japan late Friday 12/4 with an eastward track. Severe gales to storm-force should cover the 295-315 degree band relative to Hawaii while west of the dateline. This suggests a WNW long-period event building Tuesday 12/8 above average and peaking 12/9. Long range forecasts are subject to major revisions. This collaborative forecast will resume on Wednesday, December 2. This forecast was produced through the collaborative efforts of NWS and NCDDC. Please send suggestions to email@example.com or call the Warning Coordination Meteorologist at 808-973-5275. Additional resources: see /in lowercase/ http://www.prh.noaa.gov/hnl/pages/marine.php.
Collaborative Surf Table
SURF HEIGHTS WILL VARY BETWEEN DIFFERENT BEACHES AND AT THE SAME BEACH AT DIFFERENT BREAK AREAS.
Collaborative Surf Table Legend
|SWL HGT||OPEN OCEAN SWELL HEIGHT MEASURED FROM TROUGH TO CRESTIN FEET LOCATED 20 NAUTICAL MILES OFFSHORE|
|DMNT DIR||DOMINANT DIRECTION TYPICALLY +/-10 DEGREES IN 16 COMPASSPOINTS|
|DMNT PD||DOMINANT PERIOD IN SECONDS|
|H1/3||SIGNIFICANT WAVE HEIGHT IN THE SURF ZONE|
|H1/10||AVERAGE HEIGHT OF THE HIGHEST ONE-TENTH WAVES IN THE SURFZONE|
|HGT TEND||HEIGHT TENDENCY OF SWELL (VALID VALUES: UP/DOWN/SAME)|
|PROB||PROBABILITY OF OCCURRENCE (VALID VALUES: HIGH/MED/LOW)|
|WIND SPD||OPEN WATER WIND SPEED MEASURED IN KNOTS LOCATED20 NAUTICAL MILES OFFSHORE|
|WIND DIR||WIND DIRECTION IN 16 COMPASS POINTS|
|SPD TEND||WIND SPEED TENDENCY (VALID VALUES: UP/DOWN/SAME)|
NWS FORECASTER AND NCEI PAT CALDWELL