On Friday, the waiting period of the final contest of the Championship Tour begins. The Pipeline Masters begins with four surfers in mathematicial contention for the title, but only two - John John Florence and Gabriel Medina - have a realistic chance of clinching it.

The last four weeks have seen unusual surf in Hawaii with large, slow-moving highs blocking north-west storm activity. What little surf there's been has been very close to northerly in direction. This pattern is breaking down now, just in time for Pipeline, and we'll see storms following a more traditional path towards the islands.

In fact, we'll see a lot of storms. I can't recall a waiting period quite like it.

The first system is due to hit two days before the waiting period yet it's worth flagging here as it'll provide two days of 10ft+ surf which could potentially wipe the sand off the reef. Four weeks of north swells have built up truckloads of sand from Pupukea to Rockpile which will present a hindrance to classic Pipe.

The first two days of the waiting period will see good size waves cruelled by poor wind. It's possible they may be presented with small windows of opportunity but more likely they'll call laydays.

Meanwhile, the day before the waiting period begins a low pressure system will move off the Kamchatka Peninsula while cradled in a broad high to the south, the resulting pressure gradient setting up a wind field directed toward the Hawaiian islands. This swell will strike on the third morning of the waiting period - Sunday the 10th - with NE tradewinds quickly established in the wake of the system.

What sounds ideal is likely to be a bit too much of a good thing - at an expected 12-15ft the swell will overrun the Pipe reef even with an ideal wind flow. Expect Waimea and the outer reefs to be cooking.

As the swell settles over the next day the wind will remain close to NE, however just as the swell again becomes manageable the wind will go southerly. This wind shift is the precursor to a very large NW swell that will hit Hawaii on Tuesday the 12th, and if we had any worries about sand left on the reef, this system will clear it all.

Click here for a more detailed forecast of this swell.

Starting as a multi-centred low, the system will move off Japan and track north before deepening just south of the Aleutians. From there the system will slingshot in an ideal direction toward the Hawaiian islands. The system is forecast to back off just before it reaches Hawaii, however westerly winds will clip the islands ruining what would otherwise be red letter day on Hawaii's north-facing coasts.

It's the biggest storm we've seen in a few years and it'll hit right in the middle of the Pipe Masters

This final point is moot in a Pipeline forecast, the swell will be far too big for the Pipe/Backdoor stretch. At an expected 30ft-35ft (don't ask me how many Xs that is) the only possibilities are offshore deepwater breaks: Makaha, Waimea, Jaws, Outer Logs, hell maybe even Kaena Point.

Even the next day, Thursday the 14th will be too big for Pipe despite having light easterly winds. It'll be another outer reef day, maybe even Pipe's outside reefs. What say you keep the webcast cameras rolling, WSL?

By Friday we'll be halfway through the waiting period with few heats run owing to the barrage of swell. The far reaches of the model runs are showing more manageable swell, however we'll update the forecast once the competition begins.

// Guest forecast brought to you by STU 'all care, no responsibility' NETTLE

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