Hottest (avg)
#3 / 12
One of the warmer months.
September in context
How it compares to the rest of the year in Los Angeles.
Wettest (avg)
#9 / 12
Typical rainfall for the year.
Daylight Hours
#6 / 12
Around the yearly average.
Windiest (avg)
#9 / 12
Close to the yearly wind average.
Highest UV
#6 / 12
Near the middle of the yearly UV range.
Most Humid
#9 / 12
Humidity stays close to the yearly norm.
Monthly climate breakdown
A detailed look at the typical climate conditions for September.
Thermal profile
Temperature
Typical daytime high
- Nighttime low
-
- Feels like (avg)
-
Light window
Sunshine
12.4 h
Average daylight
- UV index (max)
- 8
- Typical sun hours
- 05:36 - 17:58
Wet-day pattern
Rain & Snow
Typical rainfall
- Rainy days
- 1 days
- Cloud cover (avg)
- 23%
Air feel
Humidity & Wind
58%
Average humidity
- Wind (avg)
-
- Wind (max gusts)
-
Historical daily baseline
Daily climate explorer
Pick a day to inspect the usual conditions through September in Los Angeles. Based on a 30-year historical climate baseline, not a forecast.
Primary control
Select a day
Scroll to compare daily conditions. The summary updates with your selection.
Secondary context
Monthly trend
Median daytime highs across the month, with a softer low line.
Median temperatureMedian lowTypical range
Day 15 selected for September. Temperature 29.8°C.
Historical disruption baseline
Typical disruptions in September
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in September.
Heat High impact
Hot days Measures: Hot days (>=30C). Observed about 56% of days (16.9 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
16.9 days / month
- Share of days
- ~56% of days
- Upper edge
- Up to ~39°C (P95)
Why this matters
Hot days are possible on ~17 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Heat High impact
Hot feels-like days Measures: Hot feels-like days (>=32C). Observed about 44% of days (13.3 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
13.3 days / month
- Share of days
- ~44% of days
- Upper edge
- Up to ~40°C (P95)
Why this matters
Feels-like heat >=32C is possible on ~13 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Heat High impact
Very hot feels-like Measures: Very hot feels-like days (>=35C). Observed about 21% of days (6.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
6.4 days / month
- Share of days
- ~21% of days
- Upper edge
- Up to ~42°C (P95)
Why this matters
Very hot feels-like conditions are possible on ~6 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Heat High impact
Very hot days Measures: Very hot days (>=35C). Observed about 17% of days (5.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
5.1 days / month
- Share of days
- ~17% of days
- Upper edge
- Up to ~42°C (P95)
Why this matters
Very hot days are possible on ~5 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Heat High impact
Extreme heat days Measures: Extreme heat days (>=40C). Observed about 2% of days (0.6 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.6 days / month
- Share of days
- ~2% of days
- Upper edge
- Up to ~44°C (P95)
Why this matters
Extreme heat is possible on ~1 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Heat Moderate
Heatwave run Measures: Heatwave runs (>=3 hot days). Observed about 2.4 days/month in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.4 days / month
- Share of days
- —
- Upper edge
- Up to ~39°C (P95)
Why this matters
Heatwave runs are possible on ~2 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Show all disruptions (17 more)
Rain High impact
Washout risk Measures: Washout day risk. Observed about 1% of days (0.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.4 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~20mm (P95)
Why this matters
Washout conditions are possible on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Rain High impact
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.
Likely frequency
0.1 days / month
- Share of days
- —
- Upper edge
- Up to ~15mm (P95)
Why this matters
Multi-day washout runs are possible on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Heat Moderate
Feels-like heatwave Measures: Feels-like heatwave runs (>=3 days). Observed about 2.0 days/month in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.0 days / month
- Share of days
- —
- Upper edge
- Up to ~40°C (P95)
Why this matters
Feels-like heatwave runs are possible on ~2 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Rain Moderate
Rain disruption Measures: Likely rain disruption days. Observed about 1% of days (0.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.4 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~20mm (P95)
Why this matters
Rain disruption risk appears on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Rain Moderate
Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 1% of days (0.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.2 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~21mm (P95)
Why this matters
Heavy rain is possible on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Humidity Moderate
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.
Likely frequency
0.2 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~22°C (P95)
Why this matters
Muggy conditions are possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rain Minor
Wet days Measures: Wet days (>=0.1mm). Observed about 9% of days (2.7 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.7 days / month
- Share of days
- ~9% of days
- Upper edge
- Up to ~14mm (P95)
Why this matters
Measurable rain is possible on ~3 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Cloud Minor
Cloudy days Measures: Cloudy days (cloud cover >=60%). Observed about 8% of days (2.5 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.5 days / month
- Share of days
- ~8% of days
- Upper edge
- Up to ~93% (P95)
Why this matters
Cloudy skies are possible on ~2 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Heat Minor
Warm nights Measures: Warm nights (min >=22C). Observed about 6% of days (1.8 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.8 days / month
- Share of days
- ~6% of days
- Upper edge
- Up to ~26°C (P95)
Why this matters
Warm nights are possible on ~2 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wind Minor
Gusty days Measures: Gusty days (>=40 km/h). Observed about 5% of days (1.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.4 days / month
- Share of days
- ~5% of days
- Upper edge
- Up to ~49km/h (P95)
Why this matters
Gusty conditions are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rain Minor
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 4% of days (1.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.2 days / month
- Share of days
- ~4% of days
- Upper edge
- Up to ~17h (P95)
Why this matters
Several rainy hours are possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Humidity Minor
Humid days Measures: Humid days (dew point >=18C). Observed about 4% of days (1.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.1 days / month
- Share of days
- ~4% of days
- Upper edge
- Up to ~21°C (P95)
Why this matters
Humid conditions are possible on ~1 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Cloud Minor
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 2% of days (0.7 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.7 days / month
- Share of days
- ~2% of days
- Upper edge
- Up to ~97% (P95)
Why this matters
Mostly cloudy skies are possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Humidity Minor
High humidity Measures: High humidity days (RH >=80%). Observed about 2% of days (0.6 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.6 days / month
- Share of days
- ~2% of days
- Upper edge
- Up to ~85% (P95)
Why this matters
High humidity is possible on ~1 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Rain Minor
Wet most of day Measures: Wet-most-of-day signal (>=6h rain). Observed about 2% of days (0.5 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.5 days / month
- Share of days
- ~2% of days
- Upper edge
- Up to ~18h (P95)
Why this matters
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.
Heat Minor
Heat stress risk Measures: High heat stress days. Observed about 1% of days (0.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.4 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~41°C (P95)
Why this matters
Heat stress is possible on ~0 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Heat Minor
Hot nights Measures: Hot nights (min >=25C). Observed about 1% of days (0.3 days/month) in September. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.3 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~26°C (P95)
Why this matters
Hot nights are possible on ~0 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Travel planning FAQ
Frequently asked questions
Quick answers to the weather questions you ask the most.
Is September a good time to visit Los Angeles?
Typical September days in Los Angeles reach highs of 31°C (88°F) with nights around 17°C (63°F). It usually feels hot by day and mild after dark. Overall, September sits in the middle of the Los Angeles climate range.
What are temperatures like in September?
Daytime temperatures in September typically peak near 31°C (88°F), while nights drop to around 17°C (63°F). Expect hot afternoons and mild evenings.
How much does it rain in September?
Rainfall in September averages 6 mm (0.24 in) across roughly 1 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 05:36 and sunset near 17:58. Daylight is fairly typical, with enough time for sightseeing.
How strong is the sun in September?
UV levels are often high (around 8). Regular sunscreen and a hat are recommended.
Is it windy in September?
In September, average wind speeds are around 6 km/h (4 mph), with gusts on the windiest days reaching about 38 km/h (24 mph). On the ground, it is a gentle to moderate breeze is common, but stronger winds are not frequent.