Tahiti Pro Forecast
Waiting period begins Thursday 11th August (Early Friday AEST)
We're now three days out from the start of the Tahiti Pro waiting period and things are firming up for the forecast. The main difference from then to now is a slight accleration in the systems influencing Tahiti's swell. This doesn't necessarily alter the fortunes with a whiffy first half of the waiting period giving way to greater odds in the back half.
You may recall last week's Long Range Forecast noted an against-the-grain southeast swell for the opening stanza of the contest. That swell is still is still forecast - in fact the forerunners made landfall yesterday - however it's poised to be less enduring than first impressions.
Rather than eat into the first half of the contest, it's now set to influence just the opening day two days - August 11th and 12th - and by then it'll be much smaller than at its peak. There is a very low prospect of the contest running on those days.
However, questions about what Teahupoo will look like in an 8 foot southeast swell may be answered if you keep track of social media. The swell will peak on Tuesday 9th - keep in mind that's Wednesday Oz time - at 8-10 feet from the south-southeast, so from today onwards the warm up sessions will be held in this off-kilter direction.
It's also worth noting the same swell will travel 6,500 kms and strike Australia's East Coast next Monday at a vastly reduced size - just shy of half a metre - but with a period near 15 seconds.
The aforementioned southeast swell is the product of a wind field atop a vast high pressure system stretching from New Zealand to Easter Island. The same system will suppress any storms from travelling up Tahiti's southwest swell corridor, resulting in very small conditions - too small for competition - at least up till Tuesday 16th - Day 6 of competition.
The smothering high will also interupt the flow of tradewind, turning them more east and northeast, even north - keep in mind Teahupoo likes east to southeast winds. So for four days there'll be small swell with odd winds.
By mid-next week the high will have cleared with the next low pressure system in the hatch. In fact there's more than one with the swell cycle again favouring low pressure systems travelling up New Zealand's east coast towards Tahiti.
Wednesday 17th is Day 7 of the 11 day waiting period and the first ideal day of swell. It'll result from a fetch of severe-gale winds south of New Zealand this weekend. The swell will strike Teahupoo as a large, long-period south-southwest groundswell which will build through Wednesday, reaching 8 foot on the sets into the afternoon or mid-late afternoon, before easing back from 6-8 foot on Thursday.
There's also expected to be some mid-period south-southwest swell energy in the mix from the remnants of a polar low projecting northeast towards Tahiti. This secondary swell will be under the stronger groundswell and it's worth noting the global wave models are incorrectly combining these two swells on Wednesday/Thursday, over-representing the size.
With the swell coming to the party - albeit late - what about the local winds?
Right now, they're tricky owing to a deepening tropical depression to the south-southeast of the islands mid-next week. This may bring funky onshore breezes, though in all likelihood more variable winds will develop. We'll have a clearer idea regarding the local winds over the coming days.
Following the south-southwest groundswell we're likely to see plenty of reinforcing mid-period southerly energy in the 6-8 foot range into the end of the waiting period, though this will become clearer as we head into the weekend.