Onex, Switzerland experiences average highs of 16°C (61°F) and lows of 7°C (45°F) throughout the year. Rainfall is frequent, averaging about 13 rainy days per month. Sunshine is abundant, averaging about 9 hours per day. Average highs have warmed by 1.3°C (2.3°F) across the available records.
Onex, Switzerland Weather & Climate 2026
Monthly climate averages for Onex, Switzerland. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: Feb–Oct 
Wetter season: Jan–Dec At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
5.2/10
Best: June, July, August, September
UV Index
4
Low
Temperature 16°C / 7°C
Feels Like 15°C / 6°C
Rainy Days 13
Rainfall 133 mm
Sunshine 9 h
Humidity 77%
Wind Speed 11 km/h
Dew Point 7°C
Snow Days 5 days
Frost Days 9 days
Hottest Month
25°C
August
Avg Low16°C
Rain12days
Coldest Month
-1°C
January
Avg High5°C
Rain14days
Driest Month
11days
February
Avg High9°C
Avg Low1°C
Windiest Month
12 km/h
March (Gusts 38)
Worst Time to Visit
Consider avoiding January, February, December due to very cold temperatures, frequent rain.
Sun Position
Sunrise 05:45
Daylight 15.8h
Sunset 21:30
Live conditions—
Onex on the map · live conditions
Onex, Switzerland
- Continent
- Europe
- Country
- Switzerland
- City
- Onex
- Population
- 17.3K
- Coordinates
- 46.18°, 6.10°
Seasonal Breakdown
Spring
Mar–May
Avg High 15°C
Avg Low 6°C
Rain 14 days/mo
Summer
Jun–Aug
Avg High 25°C
Avg Low 16°C
Rain 14 days/mo
3/3 best months
Autumn
Sep–Nov
Avg High 16°C
Avg Low 8°C
Rain 13 days/mo
1/3 best months
Winter
Dec–Feb
Avg High 7°C
Avg Low 0°C
Rain 13 days/mo
Climate Charts
Based on historical averages (2016–2025)
Monthly Temperatures
HighLowShaded bands show the typical range across the available yearly records.
Line chart showing monthly temperatures. Jan: 5°C / -1°C . Feb: 9°C / 1°C . Mar: 12°C / 2°C . Apr: 15°C / 6°C . May: 18°C / 9°C . Jun: 23°C / 15°C . Jul: 25°C / 16°C . Aug: 25°C / 16°C . Sep: 21°C / 12°C . Oct: 17°C / 8°C . Nov: 10°C / 3°C . Dec: 7°C / 0°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 157 mm. Feb: 99 mm. Mar: 125 mm. Apr: 105 mm. May: 159 mm. Jun: 148 mm. Jul: 120 mm. Aug: 103 mm. Sep: 128 mm. Oct: 141 mm. Nov: 147 mm. Dec: 168 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 81%. Feb: 78%. Mar: 75%. Apr: 70%. May: 75%. Jun: 74%. Jul: 70%. Aug: 70%. Sep: 77%. Oct: 81%. Nov: 84%. Dec: 84%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 12 km/h . Feb: 12 km/h . Mar: 12 km/h . Apr: 12 km/h . May: 12 km/h . Jun: 11 km/h . Jul: 11 km/h . Aug: 10 km/h . Sep: 10 km/h . Oct: 10 km/h . Nov: 10 km/h . Dec: 10 km/h .
Sunshine
Sunshine
Sunshine: Jan: 5h. Feb: 7h. Mar: 8h. Apr: 10h. May: 11h. Jun: 12h. Jul: 12h. Aug: 11h. Sep: 9h. Oct: 7h. Nov: 6h. Dec: 5h.
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 2. Feb: UV 2. Mar: UV 4. Apr: UV 5. May: UV 6. Jun: UV 7. Jul: UV 7. Aug: UV 6. Sep: UV 5. Oct: UV 3. Nov: UV 2. Dec: UV 1.
Monthly Daylight Hours
Daylight12h reference
Monthly Dew Point & Comfort
Dew Point Dry Comfortable Humid Muggy Oppressive
Snow Days
Snow DaysSnowfall
Snow Days: Jan: 10 days. Feb: 7 days. Mar: 6 days. Apr: 2 days. May: 0 days. Jun: 0 days. Jul: 0 days. Aug: 0 days. Sep: 0 days. Oct: 1 days. Nov: 4 days. Dec: 8 days.
Climate Trends
Average highs have warmed by 1.3°C (2.3°F) across the available records. Average rainfall is trending drier by about 12 mm.
2016 to 2025
Avg high Avg rainfall
Climate summary
| Last 12 months | All years | |
|---|---|---|
| Hottest month | Aug 2025 · 26°C | Aug · 25°C |
| Coldest month | Jan 2025 · 0°C | Jan · -1°C |
| Wettest month | Oct 2025 · 220 mm | Dec · 168 mm |
| Windiest month | Jan 2025 · 12 km/h | Mar · 12 km/h |
Month-by-Month Weather Table
January
Poor 
February
Poor March
Poor April
Fair May
Fair June best
Excellent July best
Excellent August best
Excellent September best
Excellent October
Fair November
Poor December
Poor | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | 5°C / -1°C | 2°C / -4°C | 14days (157 mm) Wet | 5.2h Fair | 81% Humid | 1.6 Low | Poor | View Details |
| February | 9°C / 1°C | 6°C / -2°C | 11days (99 mm) Wet | 6.7h Fair | 78% Humid | 2.4 Moderate | Poor | View Details |
| March | 12°C / 2°C | 9°C / -1°C | 13days (125 mm) Wet | 8.4h Good | 75% Muggy | 3.9 Moderate | Poor | View Details |
| April | 15°C / 6°C | 14°C / 3°C | 12days (105 mm) Wet | 10.2h Excellent | 70% Muggy | 5.4 High | Fair | View Details |
| May | 18°C / 9°C | 18°C / 8°C | 16days (159 mm) Wet | 10.5h Excellent | 75% Muggy | 5.8 High | Fair | View Details |
| June best | 23°C / 15°C | 25°C / 15°C | 16days (148 mm) Wet | 11.9h Excellent | 74% Muggy | 6.8 High | Excellent | View Details |
| July best | 25°C / 16°C | 27°C / 17°C | 13days (120 mm) Wet | 12.3h Excellent | 70% Muggy | 6.8 High | Excellent | View Details |
| August best | 25°C / 16°C | 27°C / 17°C | 12days (103 mm) Wet | 11.4h Excellent | 70% Muggy | 6.1 High | Excellent | View Details |
| September best | 21°C / 12°C | 21°C / 12°C | 12days (128 mm) Wet | 9.3h Good | 77% Humid | 4.5 Moderate | Excellent | View Details |
| October | 17°C / 8°C | 16°C / 6°C | 12days (141 mm) Wet | 7.4h Good | 81% Humid | 3 Moderate | Fair | View Details |
| November | 10°C / 3°C | 8°C / 0°C | 14days (147 mm) Wet | 5.6h Fair | 84% Humid | 1.8 Low | Poor | View Details |
| December | 7°C / 0°C | 4°C / -3°C | 14days (168 mm) Wet | 4.8h Fair | 84% Humid | 1.4 Low | Poor | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit Onex are June, July, August, September, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for Onex, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in Onex is August, with average daytime highs of 25°C (78°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in Onex is January, with average overnight lows of -1°C (31°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in Onex is December, averaging 168mm of precipitation across 14 rainy days. An umbrella or waterproof jacket is essential.
The rainy season in Onex runs through May, June, January, November, with the heaviest rainfall in May. Based on 10-year averages for Onex.
Onex receives approximately 104 sunshine hours per year. The sunniest month is July with around 12 hours. Based on climate data for Onex.
The least favorable months to visit Onex are January, February, December, primarily due to very cold temperatures, frequent rain. For the best conditions, consider June, July, August, September instead.
The annual average UV index in Onex is 4, classified as moderate. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in Onex is 77%, classified as humid. Humidity levels are generally comfortable and should not affect outdoor activities for most people.
Yes, Onex receives snow. Months with snowfall average 5 snow days and 17 cm (7 in) of accumulation, with about 9 frost days during winter.
Average wind speeds in Onex are 11 km/h (7 mph). The windiest month is March with peak winds reaching 12 km/h (7 mph) (gusts up to 38 km/h / 24 mph).
Onex averages 4 clear-sky days per month with overall cloud cover around 61%. The clearest skies occur in August.
The annual average dew point in Onex is 7°C (45°F), which feels dry and comfortable. Outdoor activities are comfortable year-round from a humidity standpoint.
Onex has a Oceanic climate, classified as Cfb under the Köppen system. Temperate climates have mild winters and warm summers, with rainfall spread across the year and four distinct seasons.
The 'feels like' temperature in Onex ranges from 6°C (43°F) to 15°C (59°F) on average. The 'feels like' temperature closely matches the actual temperature throughout most of the year.
Yes, June is a great time to visit Onex. It earns a climate score of 7.8/10 with Excellent.
For June in Onex, pack Umbrella, Waterproof jacket, Waterproof shoes, Sunscreen (SPF 30+), Sunglasses. With average highs of 23°C (74°F) and 16 rainy days, these essentials will keep you comfortable.
Data Source
Climate data derived from ERA5 reanalysis (ECMWF), averaged over 2016–2025. Sea surface temperature from marine reanalysis data. Climate scores and seasonal estimates are computed by WorldStats.
Last updated: