Athens in September
What to expect
September in Athens is early autumn, a shoulder-season window, so you can get a bit of variety across the month. It can feel distinctly hot through the middle of the day, with a noticeable cool-down after sunset. Most days feel close to what the averages suggest, with straightforward pacing. The daylight window is balanced for full days without endless late evenings.
September in context
How it compares to the rest of the year in Athens.
Monthly climate breakdown
A detailed look at the typical climate conditions for September.
Temperature
- Daytime high
-
- Nighttime low
-
- Feels like (avg)
-
Sunshine
- Daylight hours
- 12.4 h
- UV index (max)
- 7
- Typical sun hours
- 06:06 - 18:32
Rain & Snow
- Total rain
-
- Rainy days
- 5 days
- Cloud cover (avg)
- 22%
Humidity & Wind
- Humidity (avg)
- 59%
- Wind (avg)
-
- Wind (max gusts)
-
Daily climate explorer
Explore Athens's daily climate conditions for September. Based on a 30-year historical baseline, not a forecast.
Day 15 selected for September. Typical high 29.0°C and low 18.4°C.
Typical disruptions in September
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in September.
Hot days Measures: Hot days (>=30C). Observed about 32% of days (9.6 days/month) in September. Historical risk signal only, not a day-by-day forecast.
9.6 days / month
~32% of days
Why this matters
- Expected days 9.6 days / month
- Probability ~32% of days
- Intensity Up to ~35°C (P95)
Hot days are possible on ~10 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 17% of days (5.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.
5.0 days / month
~17% of days
Why this matters
- Expected days 5.0 days / month
- Probability ~17% of days
- Intensity Up to ~36°C (P95)
Feels-like heat >=32C is possible on ~5 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Strong gusts Measures: Strong gust days (>=60 km/h). Observed about 4% of days (1.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.
1.1 days / month
~4% of days
Why this matters
- Expected days 1.1 days / month
- Probability ~4% of days
- Intensity Up to ~71km/h (P95)
Strong gusts are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rain disruption Measures: Likely rain disruption days. Observed about 3% of days (1.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.
1.0 days / month
~3% of days
Why this matters
- Expected days 1.0 days / month
- Probability ~3% of days
- Intensity Up to ~30mm (P95)
Rain disruption risk appears on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Very hot feels-like Measures: Very hot feels-like days (>=35C). 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 ~39°C (P95)
Very hot feels-like conditions are possible on ~1 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Washout risk Measures: Washout day risk. 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 ~35mm (P95)
Washout conditions are possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Show all disruptions (18 more)
Heavy rain days Measures: Heavy rain days (>=10mm). 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 ~47mm (P95)
Heavy rain is possible on ~0 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 0.1 days/month in September. Historical risk signal only, not a day-by-day forecast.
0.1 days / month
Probability unavailable
Why this matters
- Expected days 0.1 days / month
- Probability —
- Intensity Up to ~54mm (P95)
Multi-day washout runs are possible on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Heatwave run Measures: Heatwave runs (>=3 hot days). Observed about 1.4 days/month in September. Historical risk signal only, not a day-by-day forecast.
1.4 days / month
Probability unavailable
Why this matters
- Expected days 1.4 days / month
- Probability —
- Intensity Up to ~35°C (P95)
Heatwave runs are possible on ~1 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Muggy days Measures: Muggy days (dew point >=20C). Observed about 1% of days (0.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.2 days / month
~1% of days
Why this matters
- Expected days 0.2 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.
Gusty days Measures: Gusty days (>=40 km/h). Observed about 34% of days (10.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.
10.1 days / month
~34% of days
Why this matters
- Expected days 10.1 days / month
- Probability ~34% of days
- Intensity Up to ~63km/h (P95)
Gusty conditions are possible on ~10 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Wet days Measures: Wet days (>=0.1mm). Observed about 23% of days (6.9 days/month) in September. Historical risk signal only, not a day-by-day forecast.
6.9 days / month
~23% of days
Why this matters
- Expected days 6.9 days / month
- Probability ~23% of days
- Intensity Up to ~10mm (P95)
Measurable rain is possible on ~7 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 12% of days (3.5 days/month) in September. Historical risk signal only, not a day-by-day forecast.
3.5 days / month
~12% of days
Why this matters
- Expected days 3.5 days / month
- Probability ~12% of days
- Intensity Up to ~16h (P95)
Several rainy hours are possible on ~4 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Humid days Measures: Humid days (dew point >=18C). Observed about 10% of days (2.9 days/month) in September. Historical risk signal only, not a day-by-day forecast.
2.9 days / month
~10% of days
Why this matters
- Expected days 2.9 days / month
- Probability ~10% of days
- Intensity Up to ~20°C (P95)
Humid conditions are possible on ~3 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Cloudy days Measures: Cloudy days (cloud cover >=60%). 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 ~94% (P95)
Cloudy skies are possible on ~3 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Warm nights Measures: Warm nights (min >=22C). 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 ~25°C (P95)
Warm nights are possible on ~2 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 5% of days (1.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
1.4 days / month
~5% of days
Why this matters
- Expected days 1.4 days / month
- Probability ~5% of days
- Intensity Up to ~16h (P95)
Wet-most-of-day conditions are possible on ~1 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 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 ~87% (P95)
High humidity is possible on ~1 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Feels-like heatwave Measures: Feels-like heatwave runs (>=3 days). Observed about 0.8 days/month in September. Historical risk signal only, not a day-by-day forecast.
0.8 days / month
Probability unavailable
Why this matters
- Expected days 0.8 days / month
- Probability —
- Intensity Up to ~35°C (P95)
Feels-like heatwave runs are possible on ~1 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 3% of days (0.8 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.8 days / month
~3% of days
Why this matters
- Expected days 0.8 days / month
- Probability ~3% of days
- Intensity Up to ~96% (P95)
Mostly cloudy skies are possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Convective risk Measures: Convective storm risk proxy. 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 ~20°C (P95)
Convective risk signal appears on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Very hot days Measures: Very hot days (>=35C). 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 ~38°C (P95)
Very hot days are possible on ~0 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Heat stress risk Measures: High heat stress days. Observed about 1% of days (0.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.2 days / month
~1% of days
Why this matters
- Expected days 0.2 days / month
- Probability ~1% of days
- Intensity Up to ~38°C (P95)
Heat stress is possible on ~0 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Hot nights Measures: Hot nights (min >=25C). Observed about 1% of days (0.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.
0.2 days / month
~1% of days
Why this matters
- Expected days 0.2 days / month
- Probability ~1% of days
- Intensity Up to ~26°C (P95)
Hot nights are possible on ~0 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Frequently asked questions
Is September a good time to visit Athens?
Typical September days in Athens reach highs of 28°C (82°F) with nights around 19°C (66°F). It usually feels hot by day and mild after dark. Overall, September sits in the middle of the Athens climate range.
What are temperatures like in September?
In September, you can usually expect highs of 28°C (82°F) and lows near 19°C (66°F). That means hot days and mild nights, so pack layers you can add or remove.
How much does it rain in September?
Rainfall in September averages 19 mm (0.75 in) across roughly 5 days. Overall it is a mostly dry time of year, so showers are usually brief rather than all-day downpours.
How many hours of daylight are there in September?
You can expect about 12 hours of daylight in September. Sunrise is typically around 06:06 and sunset near 18:32. 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 9 km/h (6 mph), with gusts on the windiest days reaching about 53 km/h (33 mph). On the ground, it is it can feel quite windy at times, particularly when weather systems move through.