Iritahama Beach Sea Temperature & Swim Forecast
Wide sand beach on the Izu west coast.
Very warm water with a light chop and a light breeze — great swimming conditions.
Location
Iritahama 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.
No wetsuit
At 27.9°C the water is warm enough to swim and surf in just a swimsuit or boardshorts.
Recommendation tuned for Iritahama Beach's current water temperature. Individual tolerance, wind chill, and session length all matter — when in doubt, size up.
Can I swim at Iritahama Beach today?
The sea is currently 27.9°C — excellent swimming conditions. Most swimmers will find it pleasant.
- • Located in Shizuoka, Japan (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 Iritahama Beach
The sea in Iritahama Beach peaks in July, when the water averages around 28°C.
The main swimming season runs from April – November, when surface temperatures stay comfortable for extended sessions.
On average, 8 months a year sit above 20°C — the threshold most swimmers describe as pleasant without a wetsuit.
Shoulder months like March and December are noticeably cooler but often quieter, with fewer crowds and steadier weather.
The coldest month is typically January at around 18°C, when cold-water swimmers dominate the coast.
Iritahama Beach sea temperature history
Long-term climatology for Iritahama Beach shows an annual mean sea temperature of 23°C, ranging from 18°C in winter to 28°C at the summer peak.
The seasonal swing is roughly 10°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 Iritahama 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.
Iritahama Beach sea temperature: frequently asked questions
What is the warmest month to swim in Iritahama Beach?
July is the warmest month in Iritahama Beach, when the sea averages about 28°C. Late-season warmth often persists a few weeks after peak.
When is the sea coldest in Iritahama Beach?
The coldest month in Iritahama Beach is typically January, when the water averages around 18°C. Cold-water swimmers and surfers dominate this period.
When can you swim in Iritahama Beach without a wetsuit?
The main swimming season in Iritahama Beach runs from April – November — about 8 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 Iritahama Beach?
Outside peak summer the water in Iritahama Beach drops toward 19°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 Iritahama Beach?
The long-term annual mean sea temperature in Iritahama Beach is about 23°C, based on multi-decadal climatology of the surrounding waters.
How do I check the current sea temperature in Iritahama Beach?
The live reading at the top of this page shows the current sea temperature in Iritahama 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: Apr – May – Jun – Jul – Aug – Sep – Oct – Nov
| Month | Sea | Comfort |
|---|---|---|
| Jan | 18°C | Pleasant |
| Feb | 18°C | Pleasant |
| Mar | 19°C | Pleasant |
| Apr | 21°C | Pleasant |
| May | 23°C | Warm |
| Jun | 26°C | Hot |
| Jul ⭐ | 28°C | Hot |
| Aug | 28°C | Hot |
| Sep | 27°C | Hot |
| Oct | 24°C | Warm |
| Nov | 21°C | Pleasant |
| Dec | 19°C | Pleasant |
Nearby beaches
The closest coastline, with live water temperatures.