Overactive period, large and dangerous Monday
Java, Bali, Lombok, Sumbawa forecast by Craig Brokensha (issued Tue 9th Sep)
Best Days: Every day over the coming period for experienced surfers
This week and weekend (Sep 10 - 14)
The weekend provided some much needed new swell energy across the region, and today a better long-range SW groundswell is filling in with some good waves breaking across Eastern Indonesia.
Today's pulse of SW groundswell should continue building through the day and reach at least 6ft by dark across exposed spots, if not slightly bigger.
This pulse should hold into Wednesday morning to 6ft to occasionally 8ft across exposed breaks ahead of a larger and better increase in S/SW groundswell through the afternoon and evening, peaking Thursday.
This has been generated by a couple of vigorous cold fronts pushing up from the Heard Island region towards WA over the weekend.
This swell should peak Thursday in the 8-10ft+ range across exposed spots in Bali before easing back just a touch into Friday ahead of a secondary reinforcing pulse Saturday. This reinforcing pulse looks to be a touch more south in direction but should maintain 8-10ft waves across exposed breaks before easing into Sunday.
Winds are expected to be moderate to fresh from the E/SE through the coming period (strongest tomorrow) with variable winds each morning in selected locations.
Next week onwards (Sep 15 onwards)
Of much greater and importance and discussed in the super long range notes for over a week and a half, a node (peak) of the Long Wave Trough currently strengthening in the Southern Indian Ocean is steering a vigorous polar front from south-east of South Africa.
This polar frontal system is one of the strongest we've seen in months, with a fetch of severe-gale to storm-force W/SW winds being produced for around 24 hours as the storm slowly moves east, north of the Heard Island region.
A very large and dangerous long-period SW groundswell will be generated for us, with the fore-runners arriving in 24s range Saturday evening before the bulk of the swell starts showing later Sunday ahead of a peak Monday morning.
Size wise we're looking at large, powerful and inconsistent 12ft+ waves at exposed spots in Bali with the odd freak 15ft set possible Monday morning.
A steady drop in size is due through the day though and further into Tuesday from 8ft+ across exposed breaks. E/SE trades look to strengthen a little Monday before easing back through the rest of the week, but we'll look at this again Thursday.
The longer term outlook remains more than active with the LWT expected to remain near stationary in the Southern Indian Ocean well into Monday week, but more on this Thursday.