Waimanalo Beach — Sea temperature now
Long east-Oahu family beach.
Very warm water with a light chop and a light breeze — great swimming conditions.
Location
Waimanalo Beach on the map, with nearby beaches and live sea temperatures.
7-day forecast
Water, air, waves, wind and UV outlook for the week ahead.
Monthly sea temperature averages
Typical year-round water temperature, based on regional climatology.
Best time to swim in Waimanalo Beach
The sea in Waimanalo Beach peaks in June, when the water averages around 27°C.
The main swimming season runs from January – December, when surface temperatures stay comfortable for extended sessions.
On average, 12 months a year sit above 20°C — the threshold most swimmers describe as pleasant without a wetsuit.
The coldest month is typically January at around 24°C, when cold-water swimmers dominate the coast.
Waimanalo Beach sea temperature history
Long-term climatology for Waimanalo Beach shows an annual mean sea temperature of 26°C, ranging from 24°C in winter to 27°C at the summer peak.
The seasonal swing is roughly 3°C between the coldest and warmest month — a useful yardstick when comparing years or checking whether the current sea is running above or below average.
Recent decades have trended slightly warmer at Waimanalo Beach, in line with regional sea-surface temperature records for the wider basin.
Monthly averages below are drawn from multi-decadal climatology and are updated as new observations arrive.
Waimanalo Beach sea temperature: frequently asked questions
What is the warmest month to swim in Waimanalo Beach?
June is the warmest month in Waimanalo Beach, when the sea averages about 27°C. Late-season warmth often persists a few weeks after peak.
When is the sea coldest in Waimanalo Beach?
The coldest month in Waimanalo Beach is typically January, when the water averages around 24°C. Cold-water swimmers and surfers dominate this period.
When can you swim in Waimanalo Beach without a wetsuit?
The main swimming season in Waimanalo Beach runs from January – December — about 12 months a year when the sea sits above 20°C, the level most swimmers describe as pleasant without a wetsuit.
Do I need a wetsuit in Waimanalo Beach?
Waimanalo Beach stays warm year-round, so most swimmers never need a wetsuit — a rash guard is usually enough for sun and wildlife protection.
What is the average sea temperature in Waimanalo Beach?
The long-term annual mean sea temperature in Waimanalo Beach is about 26°C, based on multi-decadal climatology of the surrounding waters.
How do I check the current sea temperature in Waimanalo Beach?
The live reading at the top of this page shows the current sea temperature in Waimanalo Beach, updated hourly from marine buoy and satellite data. The 7-day forecast covers water, air, waves, wind and UV for the week ahead.
Year-round sea temperature
Best swim months: Jan – Feb – Mar – Apr – May – Jun – Jul – Aug – Sep – Oct – Nov – Dec
| Month | Sea | Comfort |
|---|---|---|
| Jan | 24°C | Warm |
| Feb | 24°C | Warm |
| Mar | 24°C | Warm |
| Apr | 25°C | Warm |
| May | 26°C | Hot |
| Jun ⭐ | 27°C | Hot |
| Jul | 27°C | Hot |
| Aug | 27°C | Hot |
| Sep | 27°C | Hot |
| Oct | 27°C | Hot |
| Nov | 26°C | Hot |
| Dec | 25°C | Warm |