Weather in the Azores in September
Averages, what the month actually feels like, and what is on while you are here.
September averages
| Measurement | Ponta Delgada, south coast | Ribeira Grande, north coast | Mount Pico summitModel grid cell at 1,758 m |
|---|---|---|---|
| Average high | 23 °C | 22 °C | 15 °C |
| Average low | 21 °C | 17 °C | 8 °C |
| Daylight | 12.4 h | 12.4 h | 12.4 h |
| Sea temperature | 23 °C | – | – |
Temperature and daylight, averaged over the ten years from 2016 to 2025 and recomputed from the Open-Meteo archive rather than typed in by hand. The model works in cells roughly ten kilometres across, so each column describes an area rather than one thermometer. Checked against IPMA's Ponta Delgada normal, the temperatures land within about a degree and a half. Sea temperature averages the years 2022 to 2025. The marine record is shorter than the air record, so it rests on fewer years.
Rain in September
Ponta Delgada averages 33 mm of rain in September, on 3 days with a millimetre or more.
The high interior and the north-facing slopes are wetter than the coast in every month of the year, often several times over. IPMA publishes no station normal for the uplands or for the summit of Mount Pico, so this page puts no millimetre figure on them rather than one it cannot check.
Rainfall: the IPMA climate normal for the Ponta Delgada observatory (station 522, 58 m), averaged over the 30 years from 1981 to 2010. The ten-year reanalysis behind the table above is not used for rain. Its grid cell is about ten kilometres across and these islands are only a few cells wide, so it averages the coast with the slopes that climb behind it, where most of the rain falls. Measured against the station normal it runs well high in the summer months.
What September feels like
September keeps August's warmth with fewer people in it. The sea is still warm, the light softens through the month, and the nights start to cool off usefully.
What to pack
Summer clothes with a light waterproof towards the end of the month. Walking shoes for the long trails, which are back in comfortable condition.
What to do in September
One of the best months of the year to come. The grape harvest runs on Pico, where the vines grow in walled lava enclosures, the sea is at its warmest, and the trails are quieter than in August.
Worth knowing before you book
The first autumn showers usually arrive in the second half of the month. Tropical systems pass well to the west but can still send a heavy swell onto the north coast.
Quick answers
- How warm is it in the Azores in September?
- In Ponta Delgada an average September day reaches 23 °C and falls to 21 °C overnight. The summit of Mount Pico averages 15 °C in the same month, so the mountain needs its own layer.
- Does it rain in the Azores in September?
- Ponta Delgada records about 33 mm across September, on 3 days with a millimetre or more of rain. The north coast and the mountains take several times as much in the same weeks, which is why the two halves of the island can look like different holidays.
- Can you swim in the sea in September?
- The sea averages 23 °C in September. The Azores sit in open ocean with no shallow shelf to warm the water, so it stays close to that figure all month.
- How long are the days in September?
- About 12.4 hours between sunrise and sunset, which sets how much of a long trilho you can fit in before dark.