Nias, Mentawai, South Sumatra forecast by Craig Brokensha (issued Tue 7th Oct)

Best Days: Every day over the coming period

This week and weekend (Oct 7 - 12)

A fun pulse of S/SW swell that filled in yesterday is on the ease today, but we should see another medium-range S/SW groundswell filling in tomorrow and offering fun 4-5ft sets at exposed locations in the Ments, with 6ft sets expected in South Sumatra.

This swell should start to ease through Thursday though and really bottom out into Friday and Saturday with most locations becoming near flat. Exposed spots should pick up the odd 2-3ft sets around the Ments, but it will be really slow.

Less than favourable SE winds also look to spoil the party a little at exposed locations across the region.

Into Sunday a new long-range and very inconsistent S/SW groundswell is due to arrive, building through the day ahead of a peak overnight.

This swell, generated south-east of South Africa should provide infrequent 6ft sets across exposed spots in the Ments later Sunday and Monday morning with more consistent sets in this size range around South Sumatra. Winds look to persist from the SE in the Ments, stronger in Southern Sumatra.

Next week onwards (Sep 13 onwards)

The inconsistent long-range S/SW groundswell due later Sunday and Monday morning will ease through Monday afternoon, but a reinforcing and more S'ly swell is due into Tuesday morning, generated by a vigorous but unfavourably aligned polar frontal progression firing up in the Heard Island region and further east than ideal.

This should only keep 6ft sets hitting exposed south facing breaks in the Ments with 8ft sets around South Sumatra, before dropping off into Wednesday and further Thursday.

Winds look as if they may go a little funky into the end of the week, but we'll review this Thursday. Longer term we may see another moderate-large S/SW swell for Friday/Saturday, but check the next update for more on this.

16 day Mentawai forecast graph
16 day Nias forecast graph
16 day South Sumatra forecast graph