Climate and average weather in Thonon-les-Bains

In Thonon-les-Bains, the summers are mild, wet, and partly cloudy and the winters are cold, snowy, and partly cloudy.

Best: mid June to late September

Over the course of the year, the temperature in Thonon-les-Bains typically varies from -4°C to 22°C, and is rarely below -10°C or above 28°C. July is the hottest month of the year, while January is the coldest.

Based on the travel score, the best time of year to visit Thonon-les-Bains for warm-weather activities is from mid June to late September.

Hottest
Jul
22°
Coldest
Jan
-4°
Wettest
May
161 mm
Driest
Feb
101 mm
Rain / yr
1508 mm
167 wet days
Daylight
8.4–15.6 h
shortest–longest
Elevation
436 m
46.4°N
Clearest
Jul
51% cloud
Air quality
Good
PM10 19.5 µg/m³ · 2010

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Thonon-les-Bains weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around mid June to late September.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Thonon-les-Bains, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

The hot season lasts 3.7 months, from May 26 to September 16, with daily high temperatures above 18°C. The hottest month of the year in Thonon-les-Bains is July, with an average high of 22°C and low of 12°C.

The cool season lasts 3.6 months, from November 17 to March 5, with daily high temperatures below 7°C. The coldest month of the year in Thonon-les-Bains is January, with an average low of -4°C and high of 3°C.

Days typically run about 9°C warmer than nights, with the widest day–night swing (around 10°C) in April.

-10°10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan3-4
Feb4-4
Mar8-1
Apr122
May166
Jun2010
Jul2212
Aug2212
Sep189
Oct135
Nov70
Dec4-3

How hot and cold Thonon-les-Bains really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the coldest nights, wind chill pulls the feels-like down to about -7°C (around January 23), with roughly 158 freezing days a year (feels-like at or below 0°C), worst in January.

-10°10°20°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan33-7-4
Feb44-6-4
Mar88-3-1
Apr121212
May161666
Jun20201010
Jul22221212
Aug21221212
Sep181889
Oct131345
Nov77-20
Dec44-6-3

Average hourly temperature in Thonon-les-Bains

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on July afternoons, near 22°C, and coldest before dawn in January, near -4°C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

Thonon-les-Bains weather by month

Every month at a glance. Click a month for its detailed page.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -4°11612.310.28.80.0
Feb / -4°10111.19.4100.0
Mar / -1°10912.9811.61.5
Apr12° / 11314.45.413.32.9
May16° / 16117.71.314.74.2
Jun20° / 10°14616.20.115.55.4
Jul22° / 12°14615.4015.26.0
Aug22° / 12°13614.40146.1
Sep18° / 11513.10.212.45.3
Oct13° / 11112.7210.73.5
Nov / 12313.36.69.21.0
Dec / -3°13213.29.88.50.0

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

Thonon-les-Bains gets about 1508 mm of precipitation a year. On a typical day the chance of rain is very wet, but that rises and falls sharply with the seasons.

The wetter season lasts 4.1 months, from around Apr 16 to Aug 18, peaking in May at about 60% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Mar 14.

May is the wettest month by volume, with 161 mm over about 18 wet days; February is the driest, with 101 mm. Some of the cold-season precipitation falls as snow.

0%10%20%30%40%50%60%70%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetMay 8 · 60%Mar 14 · 38%
Rain on a day (%)Rain days
Jan4012
Feb4111
Mar4113
Apr4814
May5818
Jun5416
Jul4915
Aug4614
Sep4413
Oct4213
Nov4413
Dec4313

Monthly rainfall

Over a full year, Thonon-les-Bains collects about 1508 mm of rain across 167 wet days — roughly 126 mm in an average month.

It doesn’t fall evenly. May is the wettest month with 161 mm, while February is the driest at just 101 mm. The three wettest months alone bring about 30% of the year’s total, and some of the cold-season precipitation falls as snow.

0255075100125150175200JanFebMarAprMayJunJulAugSepOctNovDec116101109113161146146136115111123132
Rainfall (mm)Rain daysSnow days
Jan1161210
Feb101119
Mar109138
Apr113145
May161181
Jun146160
Jul146150
Aug136140
Sep115130
Oct111132
Nov123137
Dec1321310

Snow in Thonon-les-Bains

Average snowy days through the year, the snow-season span, and estimated snowfall — for ski trips and the perennial 'will there be snow at Christmas?' question.

Thonon-les-Bains averages about 53 snowy days a year. Snow season runs roughly Sep 27 to Jun 2 — about 8.2 months.

February is snowiest, with roughly 10 days of snow and an estimated 65 cm of snowfall. Over the year that adds up to an estimated 296 cm of snow.

051015JanFebMarAprMayJunJulAugSepOctNovDecsnow seasonsnow seasonFeb 12
Snow daysSnowfall (cm)
Jan1062
Feb965
Mar829
Apr532
May15
Jun00
Jul00
Aug00
Sep01
Oct26
Nov738
Dec1057

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In Thonon-les-Bains, the average share of the sky covered by clouds shows moderate seasonal variation over the course of the year.

The clearer part of the year begins around June 15 and lasts for 3.3 months, ending around September 23. The clearest month is July, when the sky is clear, mostly clear, or partly cloudy 59% of the time on average.

The cloudier part of the year begins around September 24 and lasts for 8.7 months, ending around June 14. The cloudiest month is May, when it is overcast or mostly cloudy 62% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecJul 23 · 61%May 6 · 35%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan4357
Feb4357
Mar4258
Apr4258
May3862
Jun4852
Jul5941
Aug5842
Sep5050
Oct4159
Nov3961
Dec3961

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 14, brings about 15 h 36 min of light; the shortest, around December 13, only 8 h 24 min — a swing of roughly 7 h 12 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan8.88:205:07
Feb10.07:485:49
Mar11.66:566:31
Apr13.35:557:14
May14.75:077:54
Jun15.54:478:22
Jul15.25:028:18
Aug14.05:387:38
Sep12.46:196:38
Oct10.77:005:39
Nov9.27:444:54
Dec8.58:184:43

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

Thonon-les-Bains averages about 9 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 6 and 12 days.

The sunnier stretch runs 3.1 months, from around Jun 19 to Sep 19. The sunniest month is July, with roughly 11 sunny days (mixed).

The greyest month is May, down near 7 sunny days — about 42% fewer than the July peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedJul 2312 daysMay 96 days
Sunny daysSky
Jan10Mixed
Feb8Mixed
Mar9Mixed
Apr8Mixed
May7Gloomy
Jun8Mixed
Jul12Mixed
Aug12Mixed
Sep9Mixed
Oct8Gloomy
Nov8Gloomy
Dec9Mixed

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

In Thonon-les-Bains, the air stays dry or comfortable essentially all year. Even in August, the muggiest month, it feels humid or worse only about 4% of the time — humidity is not something you need to plan around here.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDeccomfortabledry
Dry (%)Comfortable (%)Humid (%)
Jan10000
Feb10000
Mar10000
Apr10000
May9820
Jun77222
Jul58384
Aug57394
Sep9090
Oct10000
Nov10000
Dec10000

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Wind in Thonon-les-Bains is steady company: average speeds sit near 6 km/hcalm — in every month of the year, with no meaningful windy or calm season.

0510JanFebMarAprMayJunJulAugSepOctNovDeccalmDec 22 · 6 km/hAug 6 · 5 km/h
Wind speed (km/h)Feels
Jan6calm
Feb6calm
Mar6calm
Apr6calm
May6calm
Jun5calm
Jul5calm
Aug5calm
Sep5calm
Oct5calm
Nov6calm
Dec6calm

Best time to visit Thonon-les-Bains

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in Thonon-les-Bains throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around mid September, Thonon-les-Bains is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Thonon-les-Bains for general outdoor tourist activities is from mid June to late September, with a peak score in the last week of July.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationJul 27 · 6.2

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan0.0poor
Feb0.1poor
Mar1.5poor
Apr2.9poor
May4.2fair
Jun5.4fair
Jul6.1good
Aug6.1good
Sep5.2fair
Oct3.5poor
Nov1.0poor
Dec0.0poor

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Thonon-les-Bains for hot-weather activities is from late June to late August, with a peak score in the last week of July.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationJul 28 · 4.4

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for Thonon-les-Bains, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

For a warm-season trip around July (highs near 22°C), the essentials are rain gear and sun protection. In the cold season around January (highs near 3°C), pack a warm layer, a heavy coat and rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In July, Thonon-les-Bains sees daytime highs around 22°C and nights near 12°C. Pack rain gear. Worth having: sun protection. About 15 days see rain.

UV index (midday) in Thonon-les-Bains by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

Under clear skies, the midday UV index in Thonon-les-Bains peaks around July 15 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 15UV 9Dec 22UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar4Moderate
Apr5High
May7High
Jun7Very high
Jul9Very high
Aug7High
Sep5Moderate
Oct3Moderate
Nov2Low
Dec1Low

Average hourly UV index in Thonon-les-Bains

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in July the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan00
Feb00
Mar40
Apr5.50
May7.53
Jun84
Jul8.55
Aug73
Sep50
Oct1.50
Nov00
Dec00
Almanac & agriculture

Growing season

Chance of a frost-free dayTypical season (≥50%)

The growing season in Thonon-les-Bains typically lasts about 236 days, from around March 24 to November 14 — the span where a frost-free day is more likely than not. It is reliably frost-free from April 27 to October 20.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecgrowing seasonMar 2450%Apr 2790%Oct 2090%Nov 1450%
Frost-free chance (%)Frost nights
Jan1731
Feb1928
Mar4231
Apr7627
May980
Jun1000
Jul1000
Aug1000
Sep1000
Oct9213
Nov5130
Dec2331

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Thonon-les-Bains banks about 705 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around July.

0200400600800JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan0
Feb0
Mar0
Apr0
May42
Jun148
Jul215
Aug203
Sep90
Oct6
Nov0
Dec0

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Thonon-les-Bains receives about 3.6 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 1.1 and 6.0 kWh/m².

The brighter stretch of the year lasts 6.2 months, from around Mar 15 to Sep 19. The brightest month is June, averaging about 5.8 kWh/m² (bright).

The dimmest month is December, down near 1.2 kWh/m² — roughly 79% less than the June peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseJun 276.0 kWhDec 221.1 kWh
Solar energy (kWh/m²)Level
Jan1.4Dim
Feb2.4Moderate
Mar3.7Moderate
Apr4.9Bright
May5.4Bright
Jun5.8Bright
Jul5.8Bright
Aug5.1Bright
Sep3.8Moderate
Oct2.6Moderate
Nov1.6Dim
Dec1.2Dim

Where is Thonon-les-Bains?

Thonon-les-Bains sits at 46.4°N, 6.5°E, 436 m above sea level, in France. The nearest listed city is Morges, 16 km away.

Topography around Thonon-les-Bains

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Thonon-les-Bains.

Within 3 km, the terrain around Thonon-les-Bains has significant variations in elevation — a maximum elevation change of 272 m around an average of 438 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,511 m; within 80 km, extreme variations in elevation — a maximum elevation change of 4,501 m.

The land around Thonon-les-Bains is covered by trees (39%) and water (29%) within 3 km, water (39%) and trees (35%) within 16 km, and trees (50%) and grassland (32%) within 80 km.

3 km
272 m
16 km
1,511 m
80 km
4,501 m
treesgrasslandcroplandartificial surfacesbare terrainsnow and icewater
Nearby: Morges 16 km · Nyon 18 km · Lausanne 20 km · Renens 21 km · Pully 21 km · Annemasse 27 km · Vevey 30 km · Geneva 32 km

France travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / E
230 V · 50 Hz
Prices
≈ 77% of US
price level, 2025
GDP per capita
$48,986
2025
Happiness
6.6 / 10
World Happiness, 2025
Safe drinking water
100%
of population, 2024
Homicide rate
1.3
per 100k, 2023
Road deaths
5.1
per 100k/yr, 2019
Income group
High
World Bank
English
Moderate
EF EPI 539
Religion
Roman Catholic 47%none 33%Muslim 4%Protestant 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Thonon-les-Bains (46.3705°, 6.4798°, elevation 436 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).