Hawaii North Shore forecast by Steve Shearer (issued on Wed Jan 12)

This week and next (Jan12 – Jan21)

Hawaii: Surf eases back a few notches later this week and into the weekend before more big surf beckons next week. Variable winds continue with periods of light tradewinds. 

Size pushed back up into the 15ft range Tues, with early unfavourable N’ly winds gradually clocking around during the day to the E/NE. Not perfect but light enough to see surface conditions OK, especially at classic large wave spots like Waimea Bay.

Size drops from that source during Wed, back into the 12-15ft range then 6-8 through Thursday. A band of weak high pressure across Hawaii with a more defined high pressure cell to to the NE of the state maintains a weak tradewind flow through Thurs/Fri.

A more compact low tracking through the Hawaiian swell window Tues/Wed now intensifies and tracks rapidly NE later in the development phase, pushing the main bulk of swell generation towards the West Coast. Still, earlier well aimed gales still push surf back into the 8ft range Fri and with light tradewinds tending more E/SE there should be an excellent day of surfing on offer. 

Non expert-only surf continues on the weekend with surf dropping into the 6ft range Sat and Sun with continuing excellent winds- mostly light E’ly trades.

Into next week and another large cyclonic gyre forms over the North Pacific on the weekend/early next week. Gales to severe gales slingshot along the edge of the gyre, with a captured fetch reaching closer than 1000nm of Hawaii by Mon (see below). Proximity =size so expect surf to push back up into the 8ft range later Tues with the bulk of the swell filling in Wed, pushing surf back into the XL range. Expect surf in the 15ft range, larger sets at more exposed Outer Reefs. Continued light E to E/SE trades promise primo conditions for low end big wave surfing.

Size drops through Thurs, with reinforcing W/NW energy keeping wave heights in the 8-10ft range. Winds look dicey as a weak Kona low drifts over the state, bringing S’ly winds.

No end to the active period in sight. Another storm force low pushing off Japan Tues/Wed next week sees a large area of seas in excess of 30ft heading for Hawaii with another large episode from the W/NW to NW expected late Fri or Sat. Light trades should redevelop as the Kona low moves away and another weak high pressure cell moves North of Hawaii.

Stay tuned for details as we update the forecast on Fri.