Month-specific sea-surface temperature · Portugal

Azores - São Miguel Sea Temperature in September

23.7°C

74.7°F

In September, sea-surface temperature near Azores - São Miguel has a historical monthly average of 23.7°C. This is not the reading for any particular holiday date.

Across 2023–2025, the lowest and highest yearly September monthly means were 23.1–24.2°C. These are not daily extremes.

Previous month

August · 24.4°C

Change into September: -0.7°C

Next month

October · 22.3°C

Change into next month: -1.4°C

Can you swim or snorkel in Azores - São Miguel in September?

At 23.7°C our temperature-only guide describes the water as mild water. Comfort depends on your cold tolerance, immersion time and wind. A historical average cannot determine whether conditions are safe on any given day.

Do you need a wetsuit?

A rash guard is useful; cold-sensitive snorkelers may prefer a shorty wetsuit.

Which beach should you choose?

Look for a beach sheltered from the actual forecast waves and wind on your visit. Exposure, currents and entry conditions vary even where water temperatures are similar. Follow local warnings.

Check the current waves, wind and snorkeling forecast →

A live forecast does not predict a future September. Check again close to your trip.

Azores - São Miguel Sea Temperature: All 12 Months

Choose a month for available historical evidence, month comparisons and swim guidance. Missing history is clearly marked and never presented as a long-term normal.

January 17.7°C February 16.9°C March 16.4°C April 16.9°C May 18.3°C June 20.4°C July 22.4°C August 24.4°C September 23.7°C October 22.3°C November 20.0°C December 18.5°C

Data source and limitations

Source: Open-Meteo Marine API, MeteoFrance sea-surface temperature; 2023–2025. Marine model grid near 37.74, -25.68. Based on 3 yearly monthly means and 2160 recorded samples. Source methodology.

Modelled sea-surface temperatures do not establish underwater visibility, wildlife, calm currents or safe entry.