Siesta Key Water Temperature & Swim Forecast
Popular Florida Gulf beach near Siesta Key.
Very warm water with a light chop and a light breeze — great swimming conditions.
Model estimate · modelled, not a buoy measurement. How accurate is this?
Location
Siesta Key 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 29.0°C the water is warm enough to swim and surf in just a swimsuit or boardshorts.
Recommendation tuned for Siesta Key's current water temperature. Individual tolerance, wind chill, and session length all matter — when in doubt, size up.
Siesta Key swimming conditions summary
- Water temperature
- 29.0°C
- Water feels
- Bath-warm
- Swimmable today
- Yes — comfortable for most swimmers
- Swim conditions score
- 86/100 · Excellent
- Wetsuit needed
- No wetsuit
- Air temperature
- —
- Waves
- —
- Wind
- —
- UV index
- —
- Average sea temperature (September)
- 29.0 °C
- Warmest months to swim
- June, July, August
At 29.0°C the water is warm enough to swim and surf in just a swimsuit or boardshorts. 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 Siesta Key right now?
The sea at Siesta Key is currently 29.0°C — excellent 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 Siesta Key next week?
Based on long-term September averages and the latest marine model, expect the sea around Siesta Key to sit close to 27.6°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 Siesta Key?
June – July – August are typically the warmest months to swim at Siesta Key, with sea temperatures at their seasonal peak.
Do I need a wetsuit at Siesta Key?
With water currently at 29.0°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 Siesta Key today?
The sea is currently 29.0°C — excellent swimming conditions. Most swimmers will find it pleasant.
- • Located in Florida Gulf, United States (Gulf of Mexico).
- • 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 Siesta Key
The sea in Siesta Key peaks in July, when the water averages around 30°C.
The main swimming season runs from March – December, when surface temperatures stay comfortable for extended sessions.
On average, 10 months a year sit above 20°C — the threshold most swimmers describe as pleasant without a wetsuit.
Shoulder months like February and January are noticeably cooler but often quieter, with fewer crowds and steadier weather.
The coldest month is typically January at around 19°C, when cold-water swimmers dominate the coast.
Siesta Key sea temperature history
Long-term climatology for Siesta Key shows an annual mean sea temperature of 25°C, ranging from 19°C in winter to 30°C at the summer peak.
The seasonal swing is roughly 11°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 Siesta Key, 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.
Siesta Key sea temperature: frequently asked questions
What is the warmest month to swim in Siesta Key?
July is the warmest month in Siesta Key, when the sea averages about 30°C. Late-season warmth often persists a few weeks after peak.
When is the sea coldest in Siesta Key?
The coldest month in Siesta Key is typically January, when the water averages around 19°C. Cold-water swimmers and surfers dominate this period.
When can you swim in Siesta Key without a wetsuit?
The main swimming season in Siesta Key runs from March – December — about 10 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 Siesta Key?
Outside peak summer the water in Siesta Key drops toward 21°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 Siesta Key?
The long-term annual mean sea temperature in Siesta Key is about 25°C, based on multi-decadal climatology of the surrounding waters.
How do I check the current sea temperature in Siesta Key?
The live reading at the top of this page shows the current sea temperature in Siesta Key, 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: Mar – Apr – May – Jun – Jul – Aug – Sep – Oct – Nov – Dec
| Month | Sea | Comfort |
|---|---|---|
| Jan | 19°C | Pleasant |
| Feb | 19°C | Pleasant |
| Mar | 21°C | Pleasant |
| Apr | 24°C | Warm |
| May | 27°C | Hot |
| Jun | 29°C | Hot |
| Jul ⭐ | 30°C | Hot |
| Aug | 30°C | Hot |
| Sep | 29°C | Hot |
| Oct | 27°C | Hot |
| Nov | 23°C | Warm |
| Dec | 20°C | Pleasant |
Nearby beaches
The closest coastline, with live water temperatures.