Climate and average weather in Dieppe

In Dieppe, the summers are mild, showery, and partly cloudy and the winters are cold, breezy, and mostly cloudy.

Best: early June to late September

Over the course of the year, the temperature in Dieppe typically varies from 4°C to 20°C, and is rarely below -1°C or above 25°C. August is the hottest month of the year, while January is the coldest.

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

Hottest
Aug
20°
Coldest
Jan
Wettest
Dec
100 mm
Driest
Jul
54 mm
Rain / yr
835 mm
147 wet days
Daylight
7.9–16.1 h
shortest–longest
Elevation
9 m
49.9°N
Clearest
Jul
58% cloud
Air quality
Moderate
PM2.5 11.3 µg/m³ · 2019

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

Dieppe 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 early June to late September.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 3.5 months, from June 13 to September 26, with daily high temperatures above 17°C. The hottest month of the year in Dieppe is August, with an average high of 20°C and low of 15°C.

The cool season lasts 3.7 months, from November 24 to March 15, with daily high temperatures below 10°C. The coldest month of the year in Dieppe is January, with an average low of 4°C and high of 8°C.

Days typically run about 4°C warmer than nights year-round.

-5°10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan84
Feb84
Mar106
Apr127
May1510
Jun1813
Jul2015
Aug2015
Sep1813
Oct1511
Nov118
Dec85

How hot and cold Dieppe 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 -1°C (around January 28), with roughly 58 freezing days a year (feels-like at or below 0°C), worst in January.

-5°10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan7804
Feb8804
Mar101026
Apr121247
May1515910
Jun18181313
Jul20201515
Aug20201515
Sep18181313
Oct15151011
Nov111148
Dec8815

Average hourly temperature in Dieppe

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 20°C, and coldest before dawn in January, near C.

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

Dieppe 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 / 7413.20.78.41.0
Feb / 6112.30.89.71.1
Mar10° / 5811.60.511.52.1
Apr12° / 55110.113.53.2
May15° / 10°6111.3015.14.4
Jun18° / 13°5810.40165.6
Jul20° / 15°5410.5015.76.3
Aug20° / 15°6911.1014.36.2
Sep18° / 13°6311012.45.7
Oct15° / 11°8914.4010.54.0
Nov11° / 9315.70.18.82.3
Dec / 10014.90.781.3

Chance of rain

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

Dieppe gets about 835 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 5.5 months, from around Sep 23 to Mar 8, peaking in November at about 53% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jul 19.

December is the wettest month by volume, with 100 mm over about 15 wet days; July is the driest, with 54 mm.

0%10%20%30%40%50%60%JanFebMarAprMayJunJulAugSepOctNovDecwetterdrierwettermostly drysome rainoften wetvery wetNov 10 · 53%Jul 19 · 31%
Rain on a day (%)Rain days
Jan4313
Feb4412
Mar3712
Apr3611
May3711
Jun3510
Jul3311
Aug3611
Sep3811
Oct4714
Nov5216
Dec4715

Monthly rainfall

Over a full year, Dieppe collects about 835 mm of rain across 147 wet days — roughly 70 mm in an average month.

It doesn’t fall evenly. December is the wettest month with 100 mm, while July is the driest at just 54 mm. The three wettest months alone bring about 34% of the year’s total, and some of the cold-season precipitation falls as snow.

0255075100125JanFebMarAprMayJunJulAugSepOctNovDec7461585561585469638993100
Rainfall (mm)Rain daysSnow days
Jan74131
Feb61121
Mar58121
Apr55110
May61110
Jun58100
Jul54110
Aug69110
Sep63110
Oct89140
Nov93160
Dec100151

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Dieppe, 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 March 22 and lasts for 6.2 months, ending around September 25. The clearest month is July, when the sky is clear, mostly clear, or partly cloudy 50% of the time on average.

The cloudier part of the year begins around September 26 and lasts for 5.8 months, ending around March 21. The cloudiest month is November, 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 26 · 53%Nov 30 · 25%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan2872
Feb2872
Mar3565
Apr4456
May4060
Jun4456
Jul5050
Aug4852
Sep4159
Oct3268
Nov2674
Dec2674

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 12, brings about 16 h 06 min of light; the shortest, around January 1, only 7 h 54 min — a swing of roughly 8 h 12 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan8.48:555:15
Feb9.78:186:03
Mar11.57:196:51
Apr13.56:117:41
May15.15:178:27
Jun16.04:538:59
Jul15.75:098:53
Aug14.35:528:08
Sep12.46:397:01
Oct10.57:275:55
Nov8.88:185:04
Dec8.08:554:49

Sunny days

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

Dieppe 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 6.3 months, from around Mar 17 to Sep 23. The sunniest month is July, with roughly 9 sunny days (mixed).

The greyest month is November, down near 3 sunny days — about 66% fewer than the July peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedJul 2510 daysNov 203 days
Sunny daysSky
Jan4Gloomy
Feb4Gloomy
Mar6Gloomy
Apr8Gloomy
May7Gloomy
Jun7Gloomy
Jul9Mixed
Aug8Mixed
Sep6Gloomy
Oct5Gloomy
Nov3Gloomy
Dec4Gloomy

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

The more humid part of the year lasts 3.2 months, from around June 18 to September 22. The muggiest month is August, when the air feels humid, muggy or worse about 21% of the time.

The most comfortable stretch runs from around September 23 to June 17, 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 4 · 100%Aug 6 · 76%humiddrycomfortablecomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)
Jan100000
Feb100000
Mar100000
Apr100000
May93700
Jun692840
Jul3253150
Aug2850211
Sep603280
Oct841600
Nov99100
Dec100000

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 Dieppe is typically light breeze, near 20 km/h, and varies moderately with the seasons.

The windier part of the year lasts 5.6 months, from around Oct 6 to Mar 23. The windiest month is January, averaging about 24 km/h (breezy).

The calmer part of the year runs from around Mar 24 to Oct 5, with August the calmest month at about 17 km/h.

051015202530JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezebreezywindyJan 6 · 24 km/hAug 2 · 16 km/h
Wind speed (km/h)Feels
Jan24breezy
Feb22breezy
Mar21breezy
Apr18light breeze
May18light breeze
Jun17light breeze
Jul17light breeze
Aug17light breeze
Sep18light breeze
Oct21breezy
Nov22breezy
Dec23breezy

Best time to visit Dieppe

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around mid September, Dieppe 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 Dieppe for general outdoor tourist activities is from early June to late September, with a peak score in the last week of July.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationJul 24 · 6.5

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
Jan1.0poor
Feb1.1poor
Mar2.1poor
Apr3.2poor
May4.4fair
Jun5.6good
Jul6.3good
Aug6.2good
Sep5.7good
Oct4.0fair
Nov2.3poor
Dec1.3poor

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

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 1 · 3.7

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 Dieppe, 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 20°C), the essentials are rain gear and sun protection. In the cold season around January (highs near 8°C), pack a warm layer, a heavy coat, rain gear and a windbreaker.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Dieppe sees daytime highs around 20°C and nights near 15°C. Worth packing: rain gear and sun protection. About 11 days see rain.

Sea temperature near Dieppe

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 15 km away) is warmest in August at about 18°C and coldest in February near 8°C.

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

5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°C)Comfort
Jan8Bracing
Feb8Bracing
Mar8Bracing
Apr10Bracing
May12Bracing
Jun15Bracing
Jul17Cool
Aug18Cool
Sep18Cool
Oct16Cool
Nov13Bracing
Dec10Bracing

UV index (midday) in Dieppe 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 Dieppe peaks around June 19 at about 7 (high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 6 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowJun 19UV 7Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar3Moderate
Apr4Moderate
May6High
Jun7High
Jul6High
Aug7High
Sep4Moderate
Oct3Moderate
Nov1Low
Dec1Low

Average hourly UV index in Dieppe

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 June the burn window is concentrated in the middle of the day: about 7.5 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
Apr50
May6.50
Jun7.53
Jul7.52.5
Aug72.5
Sep4.50
Oct00
Nov00
Dec00

Air quality in Dieppe by month

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.

Air quality in Dieppe is worst in March — around 15 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (November, 8 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Dieppe's WHO annual average of 11.3 µg/m³.

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodMar 2415 µg/m³Nov 168 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb11Good
Mar15Moderate
Apr15Moderate
May14Moderate
Jun12Moderate
Jul11Good
Aug11Good
Sep11Good
Oct9Good
Nov8Good
Dec9Good
Almanac & agriculture

Growing season

Chance of a frost-free dayReliably frost-free (≥90%)

Dieppe is mild enough that a frost-free day stays more likely than not even in midwinter. Nights are reliably above freezing from about February 15 to December 25 (314 days); outside that window a hard frost is an occasional risk.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecreliably frost-freeFeb 1590%Dec 2590%
Frost-free chance (%)Frost nights
Jan8831
Feb9021
Mar980
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov990
Dec9310

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. Dieppe banks about 981 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

02505007501,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan0
Feb0
Mar0
Apr7
May79
Jun157
Jul228
Aug241
Sep175
Oct89
Nov5
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.

Dieppe receives about 3.4 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 0.7 and 6.1 kWh/m².

The brighter stretch of the year lasts 5.9 months, from around Mar 22 to Sep 18. The brightest month is June, averaging about 6.0 kWh/m² (intense).

The dimmest month is December, down near 0.8 kWh/m² — roughly 87% less than the June peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseJun 236.1 kWhDec 230.7 kWh
Solar energy (kWh/m²)Level
Jan0.9Dim
Feb1.8Dim
Mar3.1Moderate
Apr4.8Bright
May5.6Bright
Jun6.1Intense
Jul5.9Bright
Aug5.0Bright
Sep3.5Moderate
Oct2.1Moderate
Nov1.1Dim
Dec0.8Dim

Where is Dieppe?

Dieppe sits at 49.9°N, 1.1°E, 9 m above sea level, in France. The nearest listed city is Mont-Saint-Aignan, 51 km away.

Topography around Dieppe

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

Within 3 km, the terrain around Dieppe has only modest variations in elevation — a maximum elevation change of 101 m around an average of 33 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 191 m; within 80 km, significant variations in elevation — a maximum elevation change of 265 m.

The land around Dieppe is covered by water (34%) and artificial surfaces (24%) within 3 km, water (43%) and cropland (29%) within 16 km, and cropland (38%) and water (29%) within 80 km.

3 km
101 m
16 km
191 m
80 km
265 m
treesgrasslandcroplandartificial surfaceswater
Nearby: Mont-Saint-Aignan 51 km · Rouen 53 km · Fécamp 54 km · Canteleu 54 km · Le Petit-Quevilly 57 km · Sotteville-lès-Rouen 57 km · Abbeville 58 km · Le Grand-Quevilly 58 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 Dieppe (49.9216°, 1.0777°, elevation 9 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. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).