Rome in September
What to expect
Rome is in early autumn during September, a shoulder-season stretch where conditions can nudge warmer or cooler week to week. It leans warmly comfortable through the day, and a gentle drop-off once the sun goes down. You get a comfortable daylight window for day trips and sightseeing. Conditions tend to feel steady, which makes planning simple.
September in context
How it compares to the rest of the year in Rome.
Monthly climate breakdown
Temperature
- Daytime high
-
- Nighttime low
-
- Feels like (avg)
-
Sunshine
- Daylight hours
- 12.5 h
- UV index (max)
- 7
- Typical sun hours
- 05:50 - 18:18
Rain & Snow
- Total rain
-
- Rainy days
- 11 days
- Cloud cover (avg)
- 40%
Humidity & Wind
- Humidity (avg)
- 72%
- Wind (avg)
-
- Wind (max gusts)
-
Daily climate explorer
Day 15 selected for September. Typical high 25.4°C and low 17.1°C.
Typical disruptions in September
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in September.
Rain disruption Measures: Likely rain disruption days. Observed about 15% of days (4.6 days/month) in September. Historical risk signal only, not a day-by-day forecast.
4.6 days / month
~15% of days
Why this matters
- Expected days 4.6 days / month
- Probability ~15% of days
- Intensity Up to ~34mm (P95)
Rain disruption risk appears on ~5 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Washout risk Measures: Washout day risk. Observed about 14% of days (4.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.
4.2 days / month
~14% of days
Why this matters
- Expected days 4.2 days / month
- Probability ~14% of days
- Intensity Up to ~36mm (P95)
Washout conditions are possible on ~4 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Stormy conditions Measures: Storm-impact proxy days. Observed about 2% of days (0.6 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.6 days / month
~2% of days
Why this matters
- Expected days 0.6 days / month
- Probability ~2% of days
- Intensity Up to ~68km/h (P95)
Stormy conditions are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Hot days Measures: Hot days (>=30C). Observed about 10% of days (3.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.
3.0 days / month
~10% of days
Why this matters
- Expected days 3.0 days / month
- Probability ~10% of days
- Intensity Up to ~33°C (P95)
Hot days are possible on ~3 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Hot feels-like days Measures: Hot feels-like days (>=32C). Observed about 8% of days (2.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
2.4 days / month
~8% of days
Why this matters
- Expected days 2.4 days / month
- Probability ~8% of days
- Intensity Up to ~35°C (P95)
Feels-like heat >=32C is possible on ~2 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Heatwave run Measures: Heatwave runs (>=3 hot days). Observed about 0.5 days/month in September. Historical risk signal only, not a day-by-day forecast.
0.5 days / month
Probability unavailable
Why this matters
- Expected days 0.5 days / month
- Probability —
- Intensity Up to ~34°C (P95)
Heatwave runs are possible on ~1 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Show all disruptions (17 more)
Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 9% of days (2.7 days/month) in September. Historical risk signal only, not a day-by-day forecast.
2.7 days / month
~9% of days
Why this matters
- Expected days 2.7 days / month
- Probability ~9% of days
- Intensity Up to ~39mm (P95)
Heavy rain is possible on ~3 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Washout run Measures: Multi-day washout runs. Observed about 1.1 days/month in September. Historical risk signal only, not a day-by-day forecast.
1.1 days / month
Probability unavailable
Why this matters
- Expected days 1.1 days / month
- Probability —
- Intensity Up to ~27mm (P95)
Multi-day washout runs are possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Very heavy rain Measures: Very heavy rain days (>=25mm). Observed about 2% of days (0.7 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.7 days / month
~2% of days
Why this matters
- Expected days 0.7 days / month
- Probability ~2% of days
- Intensity Up to ~52mm (P95)
Very heavy rain is possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Strong gusts Measures: Strong gust days (>=60 km/h). Observed about 1% of days (0.3 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.3 days / month
~1% of days
Why this matters
- Expected days 0.3 days / month
- Probability ~1% of days
- Intensity Up to ~71km/h (P95)
Strong gusts are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Muggy days Measures: Muggy days (dew point >=20C). Observed about 1% of days (0.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.4 days / month
~1% of days
Why this matters
- Expected days 0.4 days / month
- Probability ~1% of days
- Intensity Up to ~21°C (P95)
Muggy conditions are possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wet days Measures: Wet days (>=0.1mm). Observed about 47% of days (14.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.
14.1 days / month
~47% of days
Why this matters
- Expected days 14.1 days / month
- Probability ~47% of days
- Intensity Up to ~25mm (P95)
Measurable rain is possible on ~14 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 31% of days (9.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
9.4 days / month
~31% of days
Why this matters
- Expected days 9.4 days / month
- Probability ~31% of days
- Intensity Up to ~19h (P95)
Several rainy hours are possible on ~9 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Cloudy days Measures: Cloudy days (cloud cover >=60%). Observed about 26% of days (7.8 days/month) in September. Historical risk signal only, not a day-by-day forecast.
7.8 days / month
~26% of days
Why this matters
- Expected days 7.8 days / month
- Probability ~26% of days
- Intensity Up to ~98% (P95)
Cloudy skies are possible on ~8 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wet most of day Measures: Wet-most-of-day signal (>=6h rain). Observed about 21% of days (6.3 days/month) in September. Historical risk signal only, not a day-by-day forecast.
6.3 days / month
~21% of days
Why this matters
- Expected days 6.3 days / month
- Probability ~21% of days
- Intensity Up to ~20h (P95)
Wet-most-of-day conditions are possible on ~6 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
High humidity Measures: High humidity days (RH >=80%). Observed about 20% of days (6.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.
6.0 days / month
~20% of days
Why this matters
- Expected days 6.0 days / month
- Probability ~20% of days
- Intensity Up to ~89% (P95)
High humidity is possible on ~6 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Gusty days Measures: Gusty days (>=40 km/h). Observed about 16% of days (4.8 days/month) in September. Historical risk signal only, not a day-by-day forecast.
4.8 days / month
~16% of days
Why this matters
- Expected days 4.8 days / month
- Probability ~16% of days
- Intensity Up to ~61km/h (P95)
Gusty conditions are possible on ~5 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Humid days Measures: Humid days (dew point >=18C). Observed about 16% of days (4.8 days/month) in September. Historical risk signal only, not a day-by-day forecast.
4.8 days / month
~16% of days
Why this matters
- Expected days 4.8 days / month
- Probability ~16% of days
- Intensity Up to ~20°C (P95)
Humid conditions are possible on ~5 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 11% of days (3.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.
3.2 days / month
~11% of days
Why this matters
- Expected days 3.2 days / month
- Probability ~11% of days
- Intensity Up to ~99% (P95)
Mostly cloudy skies are possible on ~3 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Convective risk Measures: Convective storm risk proxy. Observed about 4% of days (1.3 days/month) in September. Historical risk signal only, not a day-by-day forecast.
1.3 days / month
~4% of days
Why this matters
- Expected days 1.3 days / month
- Probability ~4% of days
- Intensity Up to ~20°C (P95)
Convective risk signal appears on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Overcast days Measures: Overcast days (cloud cover >=95%). Observed about 3% of days (0.9 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.9 days / month
~3% of days
Why this matters
- Expected days 0.9 days / month
- Probability ~3% of days
- Intensity Up to ~100% (P95)
Overcast skies are possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Feels-like heatwave Measures: Feels-like heatwave runs (>=3 days). Observed about 0.4 days/month in September. Historical risk signal only, not a day-by-day forecast.
0.4 days / month
Probability unavailable
Why this matters
- Expected days 0.4 days / month
- Probability —
- Intensity Up to ~35°C (P95)
Feels-like heatwave runs are possible on ~0 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Warm nights Measures: Warm nights (min >=22C). Observed about 1% of days (0.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.4 days / month
~1% of days
Why this matters
- Expected days 0.4 days / month
- Probability ~1% of days
- Intensity Up to ~23°C (P95)
Warm nights are possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Frequently asked questions
Is September a good time to visit Rome?
Typical September days in Rome reach highs of 26°C (79°F) with nights around 17°C (63°F). It usually feels warm by day and mild after dark. Overall, September sits in the middle of the Rome climate range.
What are temperatures like in September?
In September, you can usually expect highs of 26°C (79°F) and lows near 17°C (63°F). That means warm days and mild nights, so pack layers you can add or remove.
How much does it rain in September?
Rainfall in September averages 82 mm (3.2 in) across roughly 11 days. Overall it is a quite rainy time of year, so a light rain jacket and waterproof shoes are very handy.
How many hours of daylight are there in September?
You can expect about 12 hours of daylight in September. Sunrise is typically around 05:50 and sunset near 18:18. Daylight is fairly typical, with enough time for sightseeing.
How strong is the sun in September?
UV levels are often high (around 7). Regular sunscreen and a hat are recommended.
Is it windy in September?
In September, average wind speeds are around 8 km/h (5 mph), with gusts on the windiest days reaching about 44 km/h (27 mph). On the ground, it is it often feels breezy, especially in more exposed spots or along the coast.