Tumon Beach Water Temperature & Swim Forecast
Guam's main resort-bay swim beach.
Pleasant water with a light chop and a light breeze — great swimming conditions.
Model estimate · modelled, not a buoy measurement. How accurate is this?
Location
Tumon 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.
Rash vest or swimsuit
At 23.2°C most swimmers and surfers are comfortable in a swimsuit or thin rash top.
Recommendation tuned for Tumon Beach's current water temperature. Individual tolerance, wind chill, and session length all matter — when in doubt, size up.
Tumon Beach swimming conditions summary
- Water temperature
- 23.2°C
- Water feels
- Pleasant
- Swimmable today
- Yes — comfortable for most swimmers
- Swim conditions score
- 87/100 · Excellent
- Wetsuit needed
- Rash vest or swimsuit
- Air temperature
- —
- Waves
- —
- Wind
- —
- UV index
- —
- Average sea temperature (September)
- 23.0 °C
- Warmest months to swim
- July, August, September
At 23.2°C most swimmers and surfers are comfortable in a swimsuit or thin rash top. Model estimate. Water, wave, wind and UV values are Open-Meteo marine/weather model estimates, refreshed hourly — not buoy measurements.
Frequently asked questions
Can I swim at Tumon Beach right now?
The sea at Tumon Beach is currently 23.2°C — great swimming conditions. Most swimmers will find the water comfortable when it's above 22°C; below 18°C feels fresh and a wetsuit is recommended.
What will the sea temperature be at Tumon Beach next week?
Based on long-term September averages and the latest marine model, expect the sea around Tumon Beach to sit close to 22.3°C over the next 7 days. Check the live 7-day chart above for the exact daily outlook.
When is the best month to swim at Tumon Beach?
July – August – September are typically the warmest months to swim at Tumon Beach, with sea temperatures at their seasonal peak.
Do I need a wetsuit at Tumon Beach?
With water currently at 23.2°C: above 22°C no wetsuit needed; 18–22°C a shorty is comfortable for long swims; 14–18°C a 3/2mm full suit; below 14°C a 4/3mm or thicker.
Can I swim at Tumon Beach today?
The sea is currently 23.2°C — excellent swimming conditions. Most swimmers will find it pleasant.
- • Located in Tumon, Guam (Pacific Ocean).
- • Family friendly with calm, accessible water.
- • Live data refreshed hourly from Open-Meteo Marine.
Monthly sea temperature averages
Tap any month to see what to expect — based on regional climatology.
Best time to swim in Tumon Beach
The sea in Tumon Beach peaks in July, when the water averages around 23°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 20°C, when cold-water swimmers dominate the coast.
Tumon Beach sea temperature history
Long-term climatology for Tumon Beach shows an annual mean sea temperature of 21°C, ranging from 20°C in winter to 23°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 Tumon 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.
Tumon Beach sea temperature: frequently asked questions
What is the warmest month to swim in Tumon Beach?
July is the warmest month in Tumon Beach, when the sea averages about 23°C. Late-season warmth often persists a few weeks after peak.
When is the sea coldest in Tumon Beach?
The coldest month in Tumon Beach is typically January, when the water averages around 20°C. Cold-water swimmers and surfers dominate this period.
When can you swim in Tumon Beach without a wetsuit?
The main swimming season in Tumon 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 Tumon Beach?
Outside peak summer the water in Tumon Beach drops toward 20°C, so a 3/2mm shorty or full wetsuit makes long swims much more comfortable. In peak months most swimmers go without.
What is the average sea temperature in Tumon Beach?
The long-term annual mean sea temperature in Tumon Beach is about 21°C, based on multi-decadal climatology of the surrounding waters.
How do I check the current sea temperature in Tumon Beach?
The live reading at the top of this page shows the current sea temperature in Tumon 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 | 20°C | Pleasant |
| Feb | 20°C | Pleasant |
| Mar | 20°C | Pleasant |
| Apr | 20°C | Pleasant |
| May | 21°C | Pleasant |
| Jun | 22°C | Warm |
| Jul ⭐ | 23°C | Warm |
| Aug | 23°C | Warm |
| Sep | 23°C | Warm |
| Oct | 22°C | Warm |
| Nov | 21°C | Pleasant |
| Dec | 20°C | Pleasant |
Nearby beaches
The closest coastline, with live water temperatures.