HIGH SURF ADVISORY IN EFFECT FOR NORTH AND WEST FACING SHORES
Surf along north facing shores will increase to 6 to 10 feet this morning, to 12 to 16 feet during the afternoon, and to 18 to 24 feet tonight and Sunday.
Surf along west facing shores will increase to 4 to 8 feet this morning, to 8 to 12 feet during the afternoon, and to 12 to 18 feet tonight and Sunday.
Surf along east facing shores will be 2 to 4 feet today, increasing to 3 to 5 feet tonight and Sunday.
Surf along south facing shores will be 1 to 3 feet through Sunday.
Outlook through Saturday April 01: the large west-northwest swell will slowly decline from Sunday night through Tuesday, with advisory level surf remaining possible along exposed north and west facing shores through Monday. Surf along south facing shores should increase somewhat from Wednesday night through Friday due to a long period south swell. Another large west-northwest swell will be possible from next Friday into the following weekend.
Surf heights are forecast heights of the face or front of waves. The surf forecast is based on the significant wave height, the average height of the one third largest waves, in the zone of maximum refraction. 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 Table
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)|
SURF HEIGHTS WILL VARY BETWEEN DIFFERENT BEACHES AND AT THE SAME
BEACH AT DIFFERENT BREAK AREAS.
Collaborative Surf Discussion
Discussion: summary: Above average pattern for western to northern exposures.
Detailed: Mid Friday on has breakers below the March average from 300-320 and 340-360 degrees, respectively. These event are expected to decline on Saturday as a larger event climbs above average late in the day.
A fast-moving, compact low pressure increased in strength as it tracked east from the dateline 3/22-23 moving toward California. Highest seas were aimed NE of Hawaii. The pacioos/cdip mokapu buoy filters out much of the w-component swell, so clearly shows the new NNW event 3/24 building in the 12-16 second band. It should be short-lived, peaking late Friday and dropping Saturday from 350-010 degrees.
A low pressure system gained hurricane force as it track ENE from central Japan 3/21-23. A long, wide fetch of gales to hurricane- force winds covered the 280-305 degree band into 3/23 with the head of the fetch about 1500 nm away by late 3/23. Long-period WNW forerunners should slowly increase locally late morning Saturday morning, with surf climbing above average late afternoon. This more westerly-component swell should peak early Sunday and slowly drop into Tuesday. Shadowing by Kauai on Oahu increases error bars for the size estimate.
Addition swell from 305-320 degrees is expected to overlap, giving the maximum on Sunday from 280-320 degrees. As the low pressure system reached near 40°N, 165°E early 3/23, the tracked turned more NE. The center of low pressure has dropped to 962 mb 3/24 near 45°N just west of the dateline. Winds have favored severe gales with pockets of storm-force winds nosing to within 1300 nm 3/24.
Proximity of the high seas and swell over 30 feet just east of the dateline within 30-40°N should bring surf locally well above average. Heights should climb extra-large, meaning breakers on deep water outer reefs, overnight Saturday night. It should remain elevated Sunday, then slowly decline late Sunday into Monday, though remain above average. The direction should hold steady during this period from 280-320 degrees with dominant energy on 310 degrees. It should remain above average Tuesday with a new event due late in the day.
Models show an Aleutian low pattern holding steady centered near the dateline with several more reinforcements moving in to the area from the SW side that should keep active WNW to NW surf locally into the long range.
The next reinforcement surface low pressure cell is due to form late Friday near 35°N, 160°E and move up into the existing cell near the dateline at 45°N by Saturday. The low is modelled to change little into Monday 3/27. Gales to severe gales over the 305-320 degree band should make for a long-lived event building locally late Tuesday and peaking Wednesday at levels above average.
Mid Friday on has breakers below the trade windswell average. An increase is expected on Saturday.
Strengthening trades over and due E of Hawaii over the weekend should build the short-period surf. The fetch is narrow since the axis of high pressure sits just north of the state, placing gentle to moderate winds north of about 22°N eastward towards 140°W. This should keep the dominant wave period lower. Surf should climb to near the trade windswell average from 70-90 degrees on Sunday. It is modelled to drop a notch Monday, then hold just below average from the same direction Tuesday to Wednesday.
Mid Friday on has mostly flat conditions with tiny to small breakers at select spots. More of the same is predicted for Saturday.
The mid latitudes of the southern hemisphere from Tasmania eastward to south of French Polynesia entered a more active extratropical cyclonic mode 3/19-22. Highest seas were zonal, or more west to east. Angular spreading could make for low, long- period breakers from 180-220 degrees off and on locally 3/25-29, with odds increasing with time.
Westerly exposures should see an increase in swell for late 3/25-3/28 aforementioned.
Into the long range, a following high pressure moving east from the Tasman seas 3/23-24 has allowed more direct aim of the fetch on the west side of the low pressure SE of New Zealand. The magnitude is not sufficient for any major surf, but the location and aim of the source gives odds for surf to increase 3/30 and hold about 5 days below the summer average from 180-200 degrees.
On , above average surf 3/30 trending down just as a new event is due 3/31. The latter is based on models showing another low pressure tracking east from Japan 3/28, adding lots of 280-305 degree energy, then reaching the dateline 3/29-30 with 305-325 degree energy. This should make for a broad directions swath from 280-325 degrees at levels above average locally 3/31-4/2.
Trade windswell is expected to hold near to below average 3/30-31.
Long range forecasts are subject to major revisions.
This collaborative forecast will resume on Monday, March 27.
This forecast was produced through the collaborative efforts of NWS and ncei. 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.
NWS FORECASTER AND NCEI PAT CALDWELL