SeasonMapSt Ives weather in September
United Kingdom
September in St Ives: cool, rainy, with muggy air — a good time to visit.
#6 of 12 months in St Ives · #993 of 1383 destinations to visit in September · comfort 67/100 (tier C)
Updated September 2026 · climate normals from ERA5 reanalysis
Traveller notes on St Ives in September
Other months in St Ives
St Ives's forum is candid that August weather is genuinely a coin flip — some years dry, warm and sunny throughout, others rain for most of the month, with plenty in between. Regulars are consistent that August is also peak season locally, rammed with school-holiday visitors regardless of what the sky is doing, and point to September as a calmer alternative with comparably decent weather odds.
Add your own note from St Ives's card on the map.
St Ives climate normals — September
| Daytime high | 18°C / 64°F | 🙂 cool |
|---|---|---|
| Nighttime low | 13°C / 55°F | |
| Feels like (high) | 15°C / 59°F | |
| Sea temperature | 17°C / 62°F | 🧊 bracing |
| Rainfall | 109 mm / 4.3 in | 🌧 rainy |
| Rainy days | 14 days | |
| Humidity | 81% | 💦 very humid |
| Dew point | 12°C / 54°F | |
| Sunshine | 8.2 h/day | |
| Daylight | 12.6 h | |
| Wind | 28 km/h / 18 mph | |
| Air quality (US AQI) | 52 | 🙂 moderate |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in St Ives in September
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
BusyEnglish school holidays, school holidays in 3 of the markets that fill it(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for St Ives's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Fair weatherSt Ives's weather peaks June–August, best around July.
Best weatherFair weatherToughest weather
What's on in St Ives in September
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Holiday
English school holidays
18 Jul – 1 SepCrowdedBook earlyThe town is medieval-narrow and takes the whole of August at once. Leave the car at the Lelant park-and-ride and take the branch line in; the drive down to the harbour is a mistake. Source ↗
- Festival
St Ives September Festival
12–26 SepMajor festivalA fortnight of music, open studios and poetry across the town from the second week of September, running since 1978. The light that brought the painters here is at its best in the same weeks. Source ↗
- Season
Atlantic swell at Porthmeor
15 Sep – 31 Mar · usuallySurf seasonPorthmeor only really works when the autumn and winter groundswells come in, which is exactly when the town is empty. Wetsuits every month of the year.
Nearby, and something's on
Within 300 km of St Ives — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is St Ives?
St Ives in September — FAQ
- Is September a good time to visit St Ives?
- September in St Ives: cool, rainy, with muggy air — a good time to visit. It ranks #6 of 12 months for St Ives on SeasonMap's comfort score (67/100).
- What is the weather like in St Ives in September?
- In September, St Ives averages a daily high of 17.6°C and a low of 12.5°C, with about 108.6 mm of rain over roughly 14.4 rainy days.
- What is the air quality in St Ives in September?
- St Ives has a mean US Air Quality Index of about 52 in September.
Other months in St Ives
Compare St Ives in September
Warmer or cooler than St Ives in September
Similar destinations in Northern Europe — September
Within 300 km: Bath's Jane Austen Festival on 11–20 Sep, and Bournemouth's New Forest heather around 1 Aug – 10 Sep.