HIGH SURF ADVISORY IN EFFECT FOR NORTH AND WEST FACING SHORES
Surf along north facing shores will be 15 to 20 feet tonight, building to 18 to 24 feet Sunday. Surf along west facing shores will be 12 to 16 feet through Sunday. Surf along east facing shores will be 5 to 7 feet through Sunday. Surf along south facing shores will be 1 to 3 feet through Sunday.
Outlook through Saturday December 05: the current northwest swell will subside Sunday night through Tuesday. A new northwest swell will arrive Tuesday night into Wednesday, peak through the day Wednesday, then gradually ease Thursday and Friday. Strong onshore winds will continue to generate near advisory level surf along east facing shores through the weekend before slightly trending down Monday and Tuesday. 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.
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: Active surf within WNW clockwise around to E. Detailed: Mid Friday on northern shores has breakers near the October to April seasonal average from a mix of sources within 330-020 degrees with short to medium wave periods of 8-14 seconds. These events are expected to drop Saturday as a new long-period event builds. Surf on Thursday and Friday 11/26-27 came in higher than expected. There were two sources. The first was a low pressure tracking NE to the south of the central Aleutians 11/22-23. This source gave the maximum heights on Thursday with 15-17 second wave periods from 325-345 degrees. The second source was a low pressure cell that tracked NNE 11/24-25 with a strong trailing high pressure area, which resulted in a long fetch of strong to near gale breezes over the 350-010 degree band nosing to near the islands. It is interesting the Wave Watch III model did not pick up this event, likely due to the confusion caused by the building local windswell. Both events are expected to drop steadily late Friday into Saturday. After a mid month low spell with the primary jet stream hugging the Aleutians, a regime change has occurred as the jet strengthens and shifts southward, in line with expectations of late fall. An active pace of average to above average events are expected in the near and long range from within WNW to NNW. A low pressure deepened to hurricane-force east of the Kuril Islands on 11/24 with an ENE track. The center of low pressure crossed the dateline just south of the Aleutians 11/25 and is near 55°N, 160°W, north of Hawaii, 11/27. Models show it leaving the Hawaii swell window by Saturday. This track will give a wide directional wave range with a veering trend and be long-lived. West of the dateline, the fetch of severe gale to hurricane-force winds favored the 310-325 degree band with seas above 30 feet about 1800 nm away late Wednesday. Surf from this direction should fill in overnight Friday, with breakers climbing above average by mid morning Saturday 11/28. The more remote source for this stage of the event should make for less consistent set arrivals. Swell from this direction should peak late Saturday then slowly drop into Monday. East of the dateline, the fetch of gales to storm-force winds fell on the 320-340 degree band, nosing to near 1100 nm away Friday morning. Proximity suggests peak of local surf from this direction, which should overlap the more NW energy bringing heights to marginally extra-large, meaning breakers on select outer reefs, late Saturday into Sunday. The maximum of the event is predicted near the higher high tide near dawn Sunday, resulting in above average coastal wave wash, though at levels common during late fall through winter. The next low pressure in the series is forming even further south as the jet stream continues to shift equatorward. Storm-force winds are unfolding SE of Hokkaido, Japan 11/27. Models show the low center tracking ENE, reaching the dateline late Saturday, with the head of the fetch of severe gales about 1800 nm away. Long-period forerunners are expected to fill in locally mid Tuesday from 300-315 degrees. Surf from this direction should climb above average before dawn Wednesday, peak late Wednesday and drop below average Thursday. East of the dateline, the low center is expected to track steadily toward the gulf of Alaska, passing well north of Hawaii Tuesday with the fetch over the 315-330 degree band at the closest point to the islands about 900 nm away. Surf from this directional band should climb above average late Wednesday, and remain elevated through Thursday from 315-330 degrees. Mid Friday on eastern shores has choppy breakers above the trade windswell average for zones exposed to 000-020 degrees, and moderate breakers for the more easterly exposures. Surf should stay active on Saturday as local trades increase. See the latest NWS state forecast discussion for an explanation of the local wind expectations. The windswell from 350-020 degrees should be dropping Saturday 11/28 from the event of 11/26-27, though rising again as the new high pressure system is established north of Hawaii. Heights from 000-045 degrees should remain a notch above the trade windswell average 11/28-29. The windswell from 45-90 degrees is on the increase 11/27. A long fetch of moderate to fresh breezes within 140-160°W longitude E to ENE of Hawaii should keep breakers near the trade windswell average through the period. The locally enhanced speeds 11/28-29 to strong breezes are expected to have a shorter fetch, but long enough to keep breakers above average with a veering trend from 40 degrees 11/28 to 70 degrees by 11/30. No surf beyond tiny to small is expected on southern shores through the period. There are low odds for small, long-period breakers from 208-220 degrees 11/28-30 generated by severe gales in the southern Tasman sea 11/20-22. Into the long range, swell from the southern hemisphere should stay seasonally minimal. In the north Pacific, some models suggest the new low east of the dateline 11/29 to have an amplifying jet level trough 12/1 north of Hawaii, resulting in a se-pushing front backed by a fetch of gales over the 330-350 degree band aimed highest at targets just E of Hawaii 12/1-2. If close enough, it could take surf into the extra-large bracket 11/3 from 330-360 degrees, though likely keeping at least a notch above the seasonal average 12/3-4. Models show a low pressure forming near the northern Kurils 12/1 with a ESE track, reaching the dateline with severe gale to hurricane-force winds 12/3. This suggest extra-large WNW to NNW surf for the weekend of 12/5. E to NE windswell should hold near average into 12/3 then drop 12/4 under a local minimum of wind speeds. Long range forecasts are subject to low confidence. This collaborative forecast will resume on Monday, November 30. 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