Java, Bali, Lombok, Sumbawa forecast by Craig Brokensha (issued Tuesday 4th March)
Best Days: Every day over the coming period
This week (Mar 4 - 7 onwards)
First up, the coming week and a half is looking really good for surf in eastern Indonesia.
Yesterday's large pulse of inconsistent S/SW groundswell should of eased a touch into today but should remain fairly steady under light variable winds.
There's plenty more (slightly more consistent) swell on the way for the rest of the week as well, generated by a series of strong polar fronts pushing up from the Heard Island region towards WA late last week and over the weekend. Size wise we're looking at 4-5ft surf at exposed breaks with the rare bigger bombs at times.
The direction will continue to be from the S/SW due to the storms firing up later in our swell window in the Eastern Indian Ocean, resulting in the swell wrapping into more protected east facing spots better than SW groundswells.
Ignore the spike in swell later Friday, this is an error in the Wave Watch model, combining a building small long-range SW groundswell with an easing S/SW groundswell, over-estimating the open ocean swell size off the Indonesian coast.
We're instead expected to see inconsistent 4-6ft waves developing Friday evening before easing from 5-6ft Saturday morning.
This weekend onwards (Mar 8 onwards)
We're looking at a similar pulse of S/SW groundswell on Sunday afternoon to the pulse we saw yesterday across the Indonesian coastline, with a deep polar low firing up just west of where the remnants of Guito fired up.
This system won't be as long lived, but satellite observations confirm a fetch of 35-55kt SW winds being aimed through our southern swell window (pictured right).
A very inconsistent and large S/SW groundswell should result and build to a solid 6ft to occasionally 8ft across exposed locations during Sunday afternoon before easing slowly through Monday and further into Tuesday.
Looking at the winds over the coming period and they should be generally light and variable, although slightly stronger W'ly winds are due into Sunday and Monday, favouring east-facing breaks.
Looking longer term we're expected to see one more large S/SW groundswell into Wednesday next week from a couple of polar fronts piggybacking each other south-west of WA during the end of this week/weekend.
Beyond this a large blocking high will dominate the Indian Ocean resulting in a period of small to medium background swells from Friday 14th of March onwards.
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