Conditions at Grupuk in December
December: Clean Smallish Surf Arrives
December marks the proper return of the northwest monsoon. The average swell height drops to 1.3m (4ft) with a period of 12.7s, but the quality jumps as ideal wind reaches 33%. Swell direction is still SSW (63%) and SW (36%), with most waves in the fun, rippable 3-5ft range and a few bigger SW pulses up to 2m. West and WNW winds dominate the wind rose, creating offshore to cross-offshore conditions at Grupuk. With air temperatures around 27.6°C and water at 29.5°C, it is warm, rainy and humid - but the ocean is much cleaner. December rewards patience with glassy, lined-up waves.
Average Spot conditions at Grupuk in December
Swell history for December
Wind history for December
Swell quality
Analyze the groundswell consistency at Grupuk during December. Based on historical data, there is a % probability of groundswell occurring this month. The chart below provides a detailed breakdown of the average wave height distribution, offering deep insights into the swell quality and surf potential you can expect at Grupuk for your next trip in December.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Grupuk for December. Our analysis shows that favorable offshore or side-shore winds coincide with surfable swell approximately % of the time. The accompanying graph illustrates the average size distribution of waves during these optimal wind windows at Grupuk.