Bologna weather in September

September in Bologna: warm, rainy, with clean air — one of the best months to visit.

Updated September 2026 · climate normals from ERA5 reanalysis

Bologna🇮🇹 Italy · Northern Italy · City88
  1. 61Jan
  2. 66Feb
  3. 76Mar
  4. 87Apr
  5. 89May
  6. 84Jun
  7. 78Jul
  8. 77Aug
  9. 88Sep
  10. 83Oct
  11. 66Nov
  12. 58Dec

#2 of 12 months in Bologna · #308 of 1413 destinations to visit in September · comfort 88/100 (tier A)

Days
27°C
Nights
15°C
Wet days
9
Sun
9.9 h
Humidity
69%
Daylight
13 h
Bologna, Italy
Photo: Frank Wesneck · Pexels

Traveller notes on Bologna in September

Bologna's forum is candid that September splits in two — the first half still runs warm and beach-worthy, the second turns genuinely unpredictable, with one regular describing a 29°C day followed two days later by 19°C. Regulars call nights in September noticeably cooler than June's, worth a real layer rather than just a light one.
Tripadvisor community · September · 1 month ago · Read more on Tripadvisor ↗

Other months in Bologna

Regulars call mid-month genuinely pleasant, still warm and importantly dry, while flagging this as one of the two shoulder months, alongside April, that reliably offer milder weather even though rain becomes a real possibility as the month wears on. Our row backs that mild, increasingly wet read, 20.5C over 11.1C nights, with 73.3mm of rain across 9.2 days and humidity at 78 percent. Regulars are consistent that evenings cool down noticeably by late October, dropping toward the high single digits Celsius, enough that a real jacket replaces the light layers mid-month allows. This remains a genuinely comfortable month for exploring the porticoes and Piazza Maggiore without summer's heat. The record: 7.6 hours of sun, an 11.2 kph wind and AQI 43.
MildAndDryEarlyWetterAsMonthGoesOn · October · 1 month ago · Read more on Tripadvisor ↗
Asked whether June is too hot for this region, regulars split the month in two: the beginning can be hot by day but not unbearably so, and never in the evening or at night, while the second half is usually too hot. Our row averages 29.8C reading as 32C at 62 percent humidity, over 17.5C nights, with 54.6mm of rain across 7.7 days - a monthly average sitting between their two halves. The city's own answer to heat is structural: something like forty kilometres of portici, the arcades roofing most streets, so the centre can be crossed in shade whatever the sun is doing. They add that humidity is worse out by the river than in town. The record: 13 hours of sun, an 11.8 kph wind and AQI 52.
FortyKilometresOfArcade · June · 1 month ago · Read more on Tripadvisor ↗
Regulars warn that the two ends of April are different months here - cold at the start, especially at night, and into the twenties by the close - which our row carries as 19.4C days over 7.6C nights that feel like 5C. They concede the rain, a fair amount of it though less than March, and then give the answer the city was built with: the porticoes run through the whole centre, so wet weather is far less of an obstacle here than anywhere comparable. They were raised to shelter traders and walkers from rain and sun alike. Our 56.7mm falls across 9 days. The record: humidity 68 percent, 10.3 hours of sun, a 13.7 kph wind and AQI 45.
TheArcadesAreTheUmbrella · April · 1 month ago · Read more on Tripadvisor ↗
May in Bologna is warm without the July and August heat, and the city is at its liveliest with the students still up - though regulars are split, because some Mays turn out cold and wet. Our row explains the disagreement: 120.9mm across 12.4 precipitation days makes May one of the wettest months of the Bologna year, sitting under a pleasant 23.4C. The consolation is architectural rather than meteorological, and it is the reason this city handles rain better than most - nearly forty kilometres of porticoes, so a wet day is walkable. The end of May into June is when they say it turns near-perfect. Comfortable shoes is the other standing advice. The record: 12.4C nights, humidity 71 percent and 10.9 hours of sun.
PorticoesForTheRain · May · 1 month ago · Read more on Tripadvisor ↗

Add your own note from Bologna's card on the map.

Bologna climate normals — September

Daytime high27°C / 80°F🌤 warm
Nighttime low15°C / 59°F
Feels like (high)27°C / 81°F
Rainfall86 mm / 3.4 in🌧 rainy
Rainy days9 days
Humidity69%💧 humid
Dew point13°C / 56°F
Sunshine9.9 h/day
Daylight12.5 h
Wind11 km/h / 7 mph
Air quality (US AQI)45🍃 good

Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.

Crowds in Bologna 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.

BusySummer holidays in Italy, school holidays in 2 of the markets that fill it(estimated)

JFMAMJJASOND

Peak crowdsBusyShoulder seasonQuiet

Best months for Bologna'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).

Best weatherBologna's best weather comes in April, May and September — separate windows, not one continuous season.

JFMAMJJASOND

Best weatherFair weatherToughest weather

What's on in Bologna in September

Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.

  • Opening

    Bologna Estate

    1 Jun – 15 SepSummer season opens

    The council's summer programme moves concerts, open-air cinema and bars into the courtyards and the parks on the hill, which is how the city stays usable once the students leave. Source ↗

What's on around the world in September →

Nearby, and something's on

Within 300 km of Bologna — a day trip or a short hop — with something on this month. Never part of the comfort score.

Where is Bologna?

Loading map…

Bologna in September — FAQ

Is September a good time to visit Bologna?
September in Bologna: warm, rainy, with clean air — one of the best months to visit. It ranks #2 of 12 months for Bologna on SeasonMap's comfort score (88/100).
What is the weather like in Bologna in September?
In September, Bologna averages a daily high of 26.5°C and a low of 15.1°C, with about 85.7 mm of rain over roughly 9.1 rainy days.
What is the air quality in Bologna in September?
Bologna has a mean US Air Quality Index of about 45 in September.

Within 300 km: Verona's Arena opera festival around 10 Jun – 10 Sep, and Pisa's Anima Mundi sacred music around 5–28 Sep.