Outlook through Wednesday March 4: the west-northwest swell will continue to decline overnight. Some wrap around may be felt on the south facing shores. Trade winds will produce a short period east swell across east facing shores over the next couple of days. Another moderate northwest swell is expected to arrive early next week. 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.
No high surf advisory or warnings.
Surf along north facing shores will be 4 to 6 feet tonight, decreasing to 2 to 4 feet Friday. Surf along west facing shores will be 3 to 5 feet tonight, decreasing to 2 to 4 feet Friday. Surf along east facing shores will be 5 to 7 feet tonight, decreasing to 4 to 6 feet Friday. Surf along south facing shores will be 2 to 4 feet through Friday.
About Collaborative Surf
This collaborative forecast will be updated Monday through Friday at 300 pm when Pat Caldwell is available.
Collaborative Surf Discussion
SURF HEIGHTS WILL VARY BETWEEN DIFFERENT BEACHES AND AT THE SAME BEACH AT DIFFERENT BREAK AREAS. DISCUSSION: Summary: west swell trending down as east swell builds. Detailed: mid Wednesday has dominant swell energy from 260-300 degrees at 12-15 second intervals, giving surf for the west shore as well as the westerly exposures of the north and south shores. The episode is expected to trend down Thursday. The jet stream was at a winter southern-most position last week as it steered large surface low pressures east from near Tokyo. The second low formed 2/19, was strongest 2/20, then slowly weakened as it approached the dateline 2/22. A captured fetch formed over the 270-300 degree band. Winds were strongest 2/19-20 beyond 2400 nm away, and steadily weakened 2/21-23 as the head of the fetch reached about 1200 nm away for the 260-300 degree band. Noaa buoy 51101, 270 nm WNW of Oahu, showed the peak of the episode late Tuesday 2/24. The episode is peaking locally between midnight and noon 2/25. Surf from this W direction receives shadowing on Oahu by Niihau and Kauai, making for greater surf size variaton along a given side of the island depending on degree of shadowing. The episode is expected to steadily trend down Thursday and fade out Friday. A regime change has occurred this week as the primary jet flip-flops from an extreme southerly to a more northerly position over the north Pacific. Weaker troughs and cut-off gyres in the jet have begun to set up and are modelled to continue into the long range for the longitudes between the dateline to near Hawaii. This should turn the dominant north Pacific swell in Hawaii to more northerly components going into next week. A weak low pressure cell near 35°N, 170°W 2/25 is modelled to weaken and drift north 2/26. It could make for tiny to small, short-period surf from 325-345 degrees rising late Friday and lingering into Sunday. Models show a deepening gale associated with a cut-off in the jet stream near 40°N, 165°W Friday into Saturday. This nearly stationary surface low pressure could have gales near 1200 nm away. It could bring surf above the seasonal average on Monday from 330-350 degrees. It should peak late Monday and drop to near the seasonal average by Tuesday. See the latest NWS state forecast discussion regarding the complexities of the upcoming weather pattern governing the local winds. Mid Wednesday on eastern shores has small breakers below the average trade windswell level from 60-90 degrees. Heights are predicted to rise late Wednesday into Thursday. A large area of surface high pressure west of California in combination with a surface trough near 20°N, 140°W has set up a fetch of fresh to strong winds for the 70-100 degree band relative to Hawaii between 20 to 30°N, 130-150°W. This enhanced wind area is modelled to weaken on Thursday. The pacioos/cdip near shore buoy off Hilo, Hawaii 2/25 shows an upward trend in the 8-10 second wave period band from the east. The dominant wave period off Oahu is expected to increase Wednesday into Thursday. It should bring breakers above the trade windswell average on Thursday, peak overnight Thursday night, then hold above average into Friday night from 70-100 degrees. Heights should slowly trend down Saturday into Sunday. Models show a large surface high pressure near the dateline starting this weekend and holding into next week. In combination with lower pressure to the N to NNE of Hawaii, a more northerly component to the local winds is predicted, steadily building Saturday into Sunday. The upstream fetch to these NNE to NE winds is expected to be short. Windswell from 20-50 degrees should build Sunday into Monday, at levels below the trade windswell average. No surf beyond tiny to small is expected for the southern shores 2/26-3/1. Into the long range, an out-of-season, deep, broad low pressure formed SE of Easter Island 2/22 and moved slowly E into 2/25. Highest seas were aimed at the Americas, though the storm-force system was wide enough for angular spreading to potentially bring in small, long-period breakers locally from 160-170 degrees. Forerunners are due late Monday, with the episode peaking 3/3-4 at levels below the summer surf height average. In the north Pacific, a series of low pressure areas north of Hawaii with strong high pressure cells to either side should mean most days with shorter-period NNW to N swell 3/3-6, and peak days with moderate period swell of similar direction. Peak days should reach the seasonal average height. Models suggest the local northerly component winds to hold 3/3-6 with a mix of windswell from in the N to E quadrant at levels near the trade windswell average. Long range forecasts are subject to low confidence. This collaborative forecast will resume on Friday, February 27. 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
Collaborative Surf Table Legend
|SWL HGT||OPEN OCEAN SWELL HEIGHT MEASURED FROM TROUGH TO CREST IN FEET LOCATED 20 NAUTICAL MILES OFFSHORE|
|DMNT DIR||DOMINANT DIRECTION TYPICALLY +/-10 DEGREES IN 16 COMPASS POINTS|
|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 SURF ZONE|
|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 LOCATED 20 NAUTICAL MILES OFFSHORE|
|WIND DIR||WIND DIRECTION IN 16 COMPASS POINTS|
|SPD TEND||WIND SPEED TENDENCY (VALID VALUES: UP/DOWN/SAME)|
NWS FORECASTER AND NCDDC PAT CALDWELL