Climate and average weather in Lannion

In Lannion, the summers are mild, showery, and partly cloudy and the winters are cool, breezy, and mostly cloudy.

Best: mid June to late September

Over the course of the year, the temperature in Lannion typically varies from 6°C to 18°C, and is rarely below 3°C or above 21°C. August is the hottest month of the year, while February is the coldest.

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

Hottest
Aug
18°
Coldest
Feb
Wettest
Dec
128 mm
Driest
Jul
42 mm
Rain / yr
925 mm
153 wet days
Daylight
8.1–15.9 h
shortest–longest
Elevation
30 m
48.7°N
Clearest
Jul
57% cloud

Lannion 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 Lannion, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

The hot season lasts 3.6 months, from June 17 to October 3, with daily high temperatures above 16°C. The hottest month of the year in Lannion is August, with an average high of 18°C and low of 15°C.

The cool season lasts 4.0 months, from December 3 to April 4, with daily high temperatures below 11°C. The coldest month of the year in Lannion is February, with an average low of 6°C and high of 9°C.

Days typically run about 3°C warmer than nights year-round.

10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan97
Feb96
Mar107
Apr128
May1411
Jun1613
Jul1815
Aug1815
Sep1714
Oct1512
Nov1210
Dec108

Average hourly temperature in Lannion

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 August afternoons, near 18°C, and coldest before dawn in February, near C.

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

Lannion weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan / 10416.48.51.7
Feb / 8714.29.81.6
Mar10° / 7013.311.62.1
Apr12° / 7011.713.42.8
May14° / 11°5910.4153.9
Jun16° / 13°488.715.95.1
Jul18° / 15°42915.56.0
Aug18° / 15°509.514.26.1
Sep17° / 14°551012.45.5
Oct15° / 12°971510.54.0
Nov12° / 10°11617.392.6
Dec10° / 12817.58.11.9

Chance of rain

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

Lannion gets about 925 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.

The wetter season lasts 5.4 months, from around Sep 28 to Mar 10, peaking in November at about 58% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jul 23.

December is the wettest month by volume, with 128 mm over about 18 wet days; July is the driest, with 42 mm.

0%10%20%30%40%50%60%70%JanFebMarAprMayJunJulAugSepOctNovDecwetterdrierwettermostly drysome rainoften wetvery wetNov 29 · 58%Jul 23 · 26%
Rain on a day (%)Rain days
Jan5316
Feb5114
Mar4213
Apr3912
May3510
Jun309
Jul289
Aug3010
Sep3510
Oct4815
Nov5717
Dec5618

Monthly rainfall

Over a full year, Lannion collects about 925 mm of rain across 153 wet days — roughly 77 mm in an average month.

It doesn’t fall evenly. December is the wettest month with 128 mm, while July is the driest at just 42 mm. The three wettest months alone bring about 38% of the year’s total.

0255075100125150JanFebMarAprMayJunJulAugSepOctNovDec104877070594842505597116128
Rainfall (mm)Rain days
Jan10416
Feb8714
Mar7013
Apr7012
May5910
Jun489
Jul429
Aug5010
Sep5510
Oct9715
Nov11617
Dec12818

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Lannion, 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 May 9 and lasts for 4.9 months, ending around October 5. The clearest month is July, when the sky is clear, mostly clear, or partly cloudy 51% of the time on average.

The cloudier part of the year begins around October 6 and lasts for 5.6 months, ending around March 25. The cloudiest month is January, when it is overcast or mostly cloudy 74% 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 19 · 53%Dec 21 · 25%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan2674
Feb2971
Mar3466
Apr4456
May4159
Jun4654
Jul5149
Aug4951
Sep4753
Oct3664
Nov2971
Dec2773

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 11, brings about 15 h 54 min of light; the shortest, around January 1, only 8 h 06 min — a swing of roughly 7 h 48 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan8.59:095:38
Feb9.88:336:24
Mar11.67:377:10
Apr13.46:317:57
May15.05:398:41
Jun15.95:179:12
Jul15.55:329:06
Aug14.26:138:23
Sep12.46:587:19
Oct10.57:436:15
Nov9.08:325:26
Dec8.19:085:12

Sunny days

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

Lannion averages about 6 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 3 and 10 days.

The sunnier stretch runs 6.4 months, from around Mar 21 to Sep 30. The sunniest month is July, with roughly 10 sunny days (mixed).

The greyest month is December, down near 3 sunny days — about 70% fewer than the July peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedJul 1710 daysDec 233 days
Sunny daysSky
Jan3Gloomy
Feb4Gloomy
Mar6Gloomy
Apr7Gloomy
May7Gloomy
Jun8Gloomy
Jul10Mixed
Aug9Mixed
Sep8Gloomy
Oct4Gloomy
Nov3Gloomy
Dec3Gloomy

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 Lannion, how humid it feels changes noticeably over the year.

The more humid part of the year lasts 3.0 months, from around June 28 to September 27. The muggiest month is August, when the air feels humid, muggy or worse about 19% of the time.

The most comfortable stretch runs from around September 28 to June 27, and May is the most comfortable month — the air is dry or comfortable 100% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecMay 5 · 100%Aug 9 · 78%humidcomfortabledrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)
Jan10000
Feb10000
Mar10000
Apr10000
May9640
Jun70281
Jul296111
Aug235819
Sep52417
Oct77221
Nov9730
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.

Across the year, average wind speed in Lannion is typically breezy, near 22 km/h, and varies a lot with the seasons.

The windier part of the year lasts 5.7 months, from around Oct 12 to Apr 3. The windiest month is January, averaging about 26 km/h (breezy).

The calmer part of the year runs from around Apr 4 to Oct 11, with August the calmest month at about 17 km/h.

051015202530JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezebreezywindyJan 2 · 27 km/hAug 3 · 17 km/h
Wind speed (km/h)Feels
Jan26breezy
Feb25breezy
Mar23breezy
Apr21breezy
May20light breeze
Jun18light breeze
Jul18light breeze
Aug17light breeze
Sep20light breeze
Oct22breezy
Nov25breezy
Dec27breezy

Best time to visit Lannion

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around mid September, Lannion 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 Lannion 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 · 6.3

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
Jan1.7poor
Feb1.6poor
Mar2.1poor
Apr2.8poor
May3.9fair
Jun5.1fair
Jul6.0good
Aug6.1good
Sep5.5fair
Oct4.0fair
Nov2.7poor
Dec1.9poor

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 Lannion for hot-weather activities is from mid July to early September, with a peak score in the first week of August.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 3 · 2.3

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 Lannion, 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 August (highs near 18°C), the essentials are rain gear and sun protection. In the cold season around February (highs near 9°C), pack a warm layer, rain gear and a windbreaker.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Lannion sees daytime highs around 18°C and nights near 15°C. Worth packing: rain gear and sun protection. About 10 days see rain.

Sea temperature near Lannion

Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.

The sea at the nearest coast (about 17 km away) is warmest in August at about 17°C and coldest in March near 9°C.

The water stays below 20°C all year — cool enough that most swimmers want a wetsuit.

10°15°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°C)Comfort
Jan11Bracing
Feb10Bracing
Mar9Bracing
Apr10Bracing
May12Bracing
Jun14Bracing
Jul16Cool
Aug17Cool
Sep17Cool
Oct16Cool
Nov14Bracing
Dec12Bracing

UV index (midday) in Lannion 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 Lannion peaks around August 12 at about 7 (high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near January 11 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowAug 12UV 7Jan 11UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr5Moderate
May6High
Jun7High
Jul6High
Aug7High
Sep5Moderate
Oct3Moderate
Nov1Low
Dec1Low

Average hourly UV index in Lannion

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 August the burn window is concentrated in the middle of the day: about 7 hours a day reach index 3 (protection recommended), and 3 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
Mar00
Apr5.50
May70
Jun83
Jul7.52
Aug73
Sep50
Oct00
Nov00
Dec00
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Lannion is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecfrost-free year round
Frost-free chance (%)Frost nights
Jan1000
Feb1000
Mar1000
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec1000

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. Lannion banks about 920 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

02004006008001,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan0
Feb0
Mar0
Apr7
May67
Jun134
Jul193
Aug209
Sep170
Oct113
Nov28
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.

Lannion receives about 3.4 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 0.8 and 6.1 kWh/m².

The brighter stretch of the year lasts 6.0 months, from around Mar 23 to Sep 20. The brightest month is June, averaging about 6.0 kWh/m² (intense).

The dimmest month is December, down near 0.9 kWh/m² — roughly 85% less than the June peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseJun 206.1 kWhDec 210.8 kWh
Solar energy (kWh/m²)Level
Jan1.0Dim
Feb1.8Dim
Mar3.1Moderate
Apr4.7Bright
May5.6Bright
Jun6.0Intense
Jul5.8Bright
Aug5.0Bright
Sep3.7Moderate
Oct2.2Moderate
Nov1.3Dim
Dec0.9Dim

Where is Lannion?

Lannion sits at 48.7°N, 3.5°W, 30 m above sea level, in France. The nearest listed city is Morlaix, 32 km away.

Topography around Lannion

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Lannion.

Within 3 km, the terrain around Lannion has only modest variations in elevation — a maximum elevation change of 108 m around an average of 63 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 186 m; within 80 km, significant variations in elevation — a maximum elevation change of 381 m.

The land around Lannion is covered by trees (41%) and grassland (23%) within 3 km, trees (27%), water (27%) and cropland (23%) within 16 km, and water (41%), cropland (22%) and trees (21%) within 80 km.

3 km
108 m
16 km
186 m
80 km
381 m
treesgrasslandcroplandartificial surfaceswater
Nearby: Morlaix 32 km · Saint-Brieuc 56 km · Landerneau 66 km · Pontivy 82 km · Brest 85 km · Quimper 95 km · Douarnenez 96 km · Concarneau 101 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 Lannion (48.7326°, -3.4566°, elevation 30 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).