Java, Bali, Lombok, Sumbawa forecast by Craig Brokensha (issued Tue 24th Jun)

Best Days: Every day over the coming period, but only for experienced surfers on the large days

This week (Jun 24 - 27)

After late last week's pulse of large SW groundswell a drop in size was seen through the weekend and further into yesterday morning. A late increase in new SW groundswell should of arrived through the day and held into this morning to 8ft+ across exposed spots in Bali under moderate but freshening E/SE trades.

Into tomorrow and Thursday a slow drop in size is expected with the surf bottoming out through Thursday morning to 4-5ft at exposed spots.

Of greater importance though is one of the strongest and largest swells this year across the Indonesian Archipelago (upgraded since last Thursday's update). This has been generated by a vigorous and broad polar frontal progression developing under South Africa Thursday last week, pushing east-northeast into the Southern Indian Ocean over the weekend while producing various fetches of 35-50kt+ SW winds over a large and expansive area of ocean.

To the right I've constructed a collection of satellite images taken south-east of South Africa, showing the enormity of the weather system and peak wind speeds in the 50kt range.

The fore-runners of this swell should arrive through Thursday morning in the 23+ second range and start to show through the day, kicking by dark to 6-8ft across exposed breaks.

Friday will be very large when the swell peaks with 10-12ft+ surf expected across exposed breaks in Bali, with a touch less size further east towards Sumbawa.

This swell will only be for the very experienced surfer and fresh to strong E/SE trades will favour more sheltered breaks across the region.

This weekend onwards (Jun 23 onwards)

Friday's large and powerful SW groundswell should tail off through Saturday from 8ft to occasionally 10ft at exposed breaks and further Sunday and Monday.

The easing trend will be softened slightly into Sunday afternoon and Monday as a medium to large sized reinforcing S/SW groundswell moves in, with a low point in swell due Tuesday morning to 3ft to occasionally 5ft at exposed breaks.

The trades should back off a touch from Sunday but still remain moderate in strength through most of next week.

Longer term we should see a good pulse of large SW groundswell through next Friday and Saturday from a strong polar frontal progression rolling through the Southern Indian Ocean later this week and over the weekend, but we'll talk more about this on Thursday.

16 day Bali Forecast Graph
16 day East Java Forecast Graph
16 day Sumbawa Forecast Graph