Bath in September
What to expect
In Bath, September sits in early autumn, a shoulder-season month where the feel can shift as the season turns. Most days land in a mild, easygoing zone, with evenings that ease back comfortably. Comfort is usually predictable, so a standard day plan works well. Daylight is moderate, so steady pacing works well.
September in context
How it compares to the rest of the year in Bath.
Monthly climate breakdown
Temperature
- Daytime high
-
- Nighttime low
-
- Feels like (avg)
-
Sunshine
- Daylight hours
- 12.6 h
- UV index (max)
- 5
- Typical sun hours
- 05:45 - 18:23
Rain & Snow
- Total rain
-
- Rainy days
- 13 days
- Cloud cover (avg)
- 68%
Humidity & Wind
- Humidity (avg)
- 81%
- Wind (avg)
-
- Wind (max gusts)
-
Daily climate explorer
Day 15 selected for September. Typical high 16.9°C and low 10.1°C.
Typical disruptions in September
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in September.
Washout risk Measures: Washout day risk. Observed about 13% of days (3.9 days/month) in September. Historical risk signal only, not a day-by-day forecast.
3.9 days / month
~13% of days
Why this matters
- Expected days 3.9 days / month
- Probability ~13% of days
- Intensity Up to ~24mm (P95)
Washout conditions are possible on ~4 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 8% of days (2.3 days/month) in September. Historical risk signal only, not a day-by-day forecast.
2.3 days / month
~8% of days
Why this matters
- Expected days 2.3 days / month
- Probability ~8% of days
- Intensity Up to ~82km/h (P95)
Strong gusts are possible on ~2 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Stormy conditions Measures: Storm-impact proxy days. 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 ~80km/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.
Rain disruption Measures: Likely rain disruption days. Observed about 13% of days (3.9 days/month) in September. Historical risk signal only, not a day-by-day forecast.
3.9 days / month
~13% of days
Why this matters
- Expected days 3.9 days / month
- Probability ~13% of days
- Intensity Up to ~24mm (P95)
Rain disruption risk appears on ~4 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Cold feels-like nights Measures: Cold feels-like nights (min <=5C). 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 ~5°C (P95)
Cold feels-like nights are possible on ~3 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Fog-likely signal Measures: Fog-likely visibility proxy. 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 ~94% (P95)
Fog-likely conditions are possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Show all disruptions (15 more)
Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 6% of days (1.7 days/month) in September. Historical risk signal only, not a day-by-day forecast.
1.7 days / month
~6% of days
Why this matters
- Expected days 1.7 days / month
- Probability ~6% of days
- Intensity Up to ~33mm (P95)
Heavy rain is possible on ~2 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 0.8 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 ~33mm (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.
Severe gusts Measures: Severe gust days (>=80 km/h). 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 ~90km/h (P95)
Severe gusts are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Very heavy rain Measures: Very heavy rain days (>=25mm). 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 ~41mm (P95)
Very heavy rain is possible on ~0 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 70% of days (21.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.
21.0 days / month
~70% of days
Why this matters
- Expected days 21.0 days / month
- Probability ~70% of days
- Intensity Up to ~99% (P95)
Cloudy skies are possible on ~21 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
High humidity Measures: High humidity days (RH >=80%). Observed about 60% of days (18.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.
18.1 days / month
~60% of days
Why this matters
- Expected days 18.1 days / month
- Probability ~60% of days
- Intensity Up to ~92% (P95)
High humidity is possible on ~18 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Wet days Measures: Wet days (>=0.1mm). Observed about 57% of days (17.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.
17.0 days / month
~57% of days
Why this matters
- Expected days 17.0 days / month
- Probability ~57% of days
- Intensity Up to ~14mm (P95)
Measurable rain is possible on ~17 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Gusty days Measures: Gusty days (>=40 km/h). Observed about 45% of days (13.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
13.4 days / month
~45% of days
Why this matters
- Expected days 13.4 days / month
- Probability ~45% of days
- Intensity Up to ~70km/h (P95)
Gusty conditions are possible on ~13 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 42% of days (12.5 days/month) in September. Historical risk signal only, not a day-by-day forecast.
12.5 days / month
~42% of days
Why this matters
- Expected days 12.5 days / month
- Probability ~42% of days
- Intensity Up to ~17h (P95)
Several rainy hours are possible on ~12 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 37% of days (11.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.
11.1 days / month
~37% of days
Why this matters
- Expected days 11.1 days / month
- Probability ~37% of days
- Intensity Up to ~100% (P95)
Mostly cloudy skies are possible on ~11 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 28% of days (8.5 days/month) in September. Historical risk signal only, not a day-by-day forecast.
8.5 days / month
~28% of days
Why this matters
- Expected days 8.5 days / month
- Probability ~28% of days
- Intensity Up to ~18h (P95)
Wet-most-of-day conditions are possible on ~9 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Overcast days Measures: Overcast days (cloud cover >=95%). Observed about 12% of days (3.6 days/month) in September. Historical risk signal only, not a day-by-day forecast.
3.6 days / month
~12% of days
Why this matters
- Expected days 3.6 days / month
- Probability ~12% of days
- Intensity Up to ~100% (P95)
Overcast skies are possible on ~4 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data Measures: Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data. 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 ~94 (P95)
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data is possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Breezy days Measures: Breezy days (mean wind >=25 km/h). 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 ~31km/h (P95)
Breezy conditions are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Cold nights Measures: Cold nights (min <=5C). 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 ~5°C (P95)
Cold nights are possible on ~0 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Frequently asked questions
Is September a good time to visit Bath?
Typical September days in Bath reach highs of 18°C (64°F) with nights around 11°C (52°F). It usually feels mild by day and cool after dark. Overall, September sits in the middle of the Bath climate range.
What are temperatures like in September?
In September, you can usually expect highs of 18°C (64°F) and lows near 11°C (52°F). That means mild days and cool nights, so pack layers you can add or remove.
How much does it rain in September?
Rainfall in September averages 61 mm (2.4 in) across roughly 13 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 13 hours of daylight in September. Sunrise is typically around 05:45 and sunset near 18:23. Daylight is fairly typical, with enough time for sightseeing.
How strong is the sun in September?
UV levels are moderate (around 5); sunscreen and sunglasses are still a good idea.
Is it windy in September?
In September, average wind speeds are around 14 km/h (9 mph), with gusts on the windiest days reaching about 58 km/h (36 mph). On the ground, it is it can feel quite windy at times, particularly when weather systems move through.