Geneva Weather in September

🇨🇭 Switzerland

20°C

High

12°C

Low

Rain Days

Sunshine

65%

Humidity

Europe › 🇨🇭 Switzerland › Geneva

Updated: March 2026

Is September a Good Time to Visit Geneva?

6/10

Good

September is a good time to visit Geneva (6/10). With 9 daily sunshine hours and only 12 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 6th sunniest of the year in Geneva. Culture-focused travellers and those who prefer lighter crowds will find September a practical choice, with prices running lower than peak June without sacrificing all the good weather. October offers a similar profile at lower hotel rates if dates are flexible. The main practical note: Geneva's popular sites are busiest between 10am and 3pm regardless of season. Arriving at opening time or after 4pm makes a significant difference to the experience. Planning tips: accommodation is generally available without long lead times, and flight prices are typically lower than peak season. Flexible travellers will find the best deals by booking 2-4 weeks ahead. Mid-week arrivals consistently unlock lower hotel rates than weekend check-ins.

vs August:24°C avg high

Step off the plane in Geneva in September and the air meets you at around 20°C, a temperature that feels genuinely welcoming after a long flight. By the time evening arrives and temperatures settle near 12°C, the city takes on a different character entirely. With 9 hours of daylight sun on offer, September gives you the raw material for a genuinely memorable trip.

20°C

Avg High

12°C

Avg Low

12 days

Rain Days

Sunshine

65%

Humidity

Temperature in Geneva in September

The 8°C day-night temperature range is typical for continental climates: a light jacket in the morning that you shed by midday and need again after sunset. Humidity averages 65%, which is comfortable for most visitors. On warmer days, lighter fabrics help with the mild stickiness in the afternoon. UV index averages 6 this month, classed as moderate. Sunscreen is a sensible precaution for extended outdoor time, particularly at midday. Winds are calm at an average 10 km/h, so wind-chill is not a factor in planning your clothing. In Fahrenheit: 68°F average high, 54°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).

Temperature in September

Monthly Precipitation (mm)

What to Wear in Geneva in September

Morning12°CBefore the day warms up

Afternoon20°CPeak daytime temperature

Evening15°CAfter sunset cools down

Packing for Geneva in September means dressing for 20°C days and 12°C evenings. A light cotton tee with a casual overshirt works well at 20°C, the overshirt doubles as a layer for air-conditioned venues. Evening temperatures settle at 12°C, a modest 8°C drop that a light cardigan or denim jacket covers. European cobblestones reward low-profile walking shoes over flip-flops or heels, with cushioned trainers or leather walking shoes being the practical choice. A compact foldable umbrella weighs almost nothing and earns its keep across 12 potential rainy days.

💡

Local tip: Geneva's cobbled streets turn slippery in the rain. Waterproof walking shoes with a non-slip sole outperform fashionable footwear on wet stone, and you'll cover significantly more ground in comfort.

Events in Geneva in September

September has no major festivals or public holidays in Geneva, which is one of its practical advantages for independent travellers. Attractions run at lower capacity than during peak event periods, queues are shorter, and accommodation is easier to find without needing to book many months in advance. Local restaurants, markets, and transport operate at a relaxed pace, making this an ideal time for visitors who prefer a more authentic, unhurried experience of everyday city life rather than large crowds drawn in by a single major headline event.

What to Pack for Geneva in September

Based on 20°C average highs and 12 rainy days

Light jacket or cardigan for cooler evenings
Mix of short and long-sleeve layers
Comfortable walking shoes with good arch support
Compact folding umbrella
Waterproof outer layer or packable rain jacket
Quick-dry clothing that recovers fast after a shower
Universal travel adapter
Small day pack for city exploration
Reusable water bottle

Best Activities in Geneva in September

Explore outdoor markets and street food stallsMid-morning (10am-12pm)At 20°C, the temperature is ideal for extended walking without overheating
Guided walking tour of the historic centreMorning or late afternoonComfortable temperatures allow several hours on foot without fatigue
Visit rooftop viewpoints and observation decksGolden hour (1 hour before sunset)Warm clear evenings provide exceptional visibility for panoramic photography
Day trip to the surrounding countryside or coastFull day (depart by 8am)September is reliably dry enough for rural day trips without weather risk
Afternoon in a world-class museum or galleryAfternoon (2-5pm)Pairs well with outdoor morning activities and provides a mid-day rest from sightseeing
Coffee-house or traditional cafe culture experienceMid-morning or post-lunchA cultural ritual in this region that rewards slow appreciation regardless of weather
Evening live music, theatre, or opera performanceEvening shows typically at 7-9pmConsistent evening temperatures make getting to and from evening venues comfortable
Visit the main botanical garden or city park at seasonal peakYear-round; best light in morningSeptember brings distinct seasonal changes to public green spaces worth exploring
Try the seasonal farmer's market for local produce and street foodSaturday morning markets typically 8am-1pmSeptember seasonal produce is at peak availability, offering dishes not found at other times of year

Why is Geneva mild in September?

September brings the first meaningful shift toward cooler conditions in Geneva, as the sun angle drops and day length shortens. Temperatures averaging 20°C by day and 12°C overnight are still comfortable by most standards, but the trend is clearly downward. At 46 degrees north latitude, autumn light has a particular quality: lower in the sky and warmer in tone, it gives the city a photogenic quality quite different from summer. Conditions remain excellent for outdoor activity, and crowds thin compared to the summer peak. Climate data: Open-Meteo ERA5 (1991–2020).

Sunshine Hours

The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.

UV Index

A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate -- wear sunscreen. UV 6-7: High -- hat and SPF 30+ essential. UV 8-10: Very High -- limit midday exposure. UV 11+: Extreme -- seek shade between 10am-4pm.

Rain Days

A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.

Humidity

Relative humidity as a percentage. Below 40%: Dry -- skin and throat may feel parched. 40-60%: Comfortable -- ideal for most people. 60-80%: Sticky -- light, breathable fabrics recommended. Above 80%: Muggy -- heat feels more intense; quick-dry clothing is essential.

Frequently Asked Questions: Geneva in September

In September, Geneva experiences average highs of 20°C (68°F) and lows of 12°C (54°F). Expect around 12 rainy days and 9 hours of sunshine per day, with humidity averaging 65%. The 8°C gap between daytime and overnight temperatures is worth planning around: light layers work for most visitors during the day, but an overshirt or cardigan handles the cooler evenings. UV index averages 6, so sun protection is advisable on clear days.

Geneva typically sees 12 rainy days in September, with total precipitation of around 108mm. Rain is moderate and manageable. Showers tend to pass quickly, and a light rain layer or foldable umbrella is sufficient protection for most days. For context, the driest month in Geneva typically sees 4-6 fewer rain days than September.

Pack light layers, a light jacket for evenings, comfortable walking shoes, and sunscreen for Geneva in September. Daytime temperatures of 20°C are pleasant, but the evening drop to 12°C means a jacket is essential if you plan to be out after dark. With 12 rainy days, bring a compact umbrella or waterproof jacket for unexpected showers. Comfortable walking shoes are a priority given the amount of ground most visitors cover.

September is a reasonable time to visit Geneva. Expect 12 rainy days, so pack a light rain layer for flexibility. Average temperatures of 20°C make outdoor exploration comfortable during the dry periods. With 9 daily sunshine hours, there are reliable windows of good weather to plan outdoor activities around, even if the month is not the driest on the calendar.

The average high temperature in Geneva in September is 20°C (68°F), and the average low is 12°C (54°F). The mean daily temperature is approximately 16°C (61°F). The day-to-night range of 8°C is moderate, meaning a single light jacket covers most situations. These are 30-year climate normals based on the 1991 to 2020 reference period; individual years will vary, particularly in transitional months like spring and autumn.

The best month to visit Geneva is generally February. February offers the most sunshine at 7 hours per day and only 11 rainy days. Average temperatures reach 7°C, making it comfortable for sightseeing, outdoor dining, and exploring the city. If your travel dates are flexible, planning your trip around February gives you the best chance of dry, bright weather.

September is shoulder or low season in Geneva, meaning fewer tourists and generally lower prices than peak months. With 9 sunshine hours and 12 rainy days, the weather is less of a draw for mass tourism. This is an advantage for travellers who prefer a quieter, more relaxed experience with shorter queues and easier accommodation availability.

In September, Geneva suits a range of activities thanks to mild temperatures around 20°C. Mix of indoor and outdoor activities works well given the moderate chance of rain. Top options include exploring historic neighbourhoods, visiting museums and galleries, local food markets, and day trips to surrounding areas. With 9 hours of sunshine, parks and waterfront walks are particularly enjoyable.

September ranks 6th sunniest of the year in Geneva, with an average 9 daily sunshine hours. The driest months are February, August, and September. July is the hottest month (24°C avg high); January is the coolest (5°C). From here, temperatures fall 4°C into October. Compared to last month (August: 24°C high, 12 rain days), September is cooler and equally dry. September sits in the middle of the annual sunshine ranking for Geneva, offering a reasonable balance of good weather and manageable crowds.

Year-Round Climate

Month	High	Low	Rain Days	Sun	Details
January	5°C	-1°C	13	5h	View
February	7°C	0°C	11	7h	View
March	11°C	2°C	13	8h	View
April	15°C	5°C	13	10h	View
May	19°C	10°C	16	10h	View
June	22°C	13°C	14	12h	View
July	24°C	16°C	13	12h	View
August	24°C	16°C	12	11h	View
September	20°C	12°C	12	9h	View
October	16°C	8°C	12	7h	View
November	10°C	3°C	13	6h	View
December	6°C	0°C	13	5h	View

Other Months in Geneva

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Plan Your Trip to Geneva

Best Time to Visit Geneva Geneva vs Paris in September Geneva vs Munich in September

Nearby Destinations with Similar Weather

These cities are within 500 km and experience broadly comparable weather conditions during the same calendar month, making them practical standalone alternatives or worthwhile additions to a longer regional itinerary.

Paris🇫🇷 France410 km away

21°C12°C low

Munich🇩🇪 Germany464 km away

18°C10°C low

Milan🇮🇹 Italy250 km away

23°C14°C low

Lyon🇫🇷 France112 km away

22°C13°C low

Data Sources for Geneva

Geneva on Wikipedia Open-Meteo Climate API NOAA National Centers UK Met Office WMO GeoNames

Climate normals represent 30-year averages (1991-2020). Individual years may vary.