Calais in Summer
In summer (June, July and August), Calais sees average daytime highs around 18°C and overnight lows near 15°C, with 165 mm of rain over about 28 wet days across the season. It is the warmest season of the year and the 3rd-wettest season.
Over the season highs climb from about 15°C in early June to 19°C by late August. The sky is clear or mostly clear about 28% of the time across summer, and the air most often feels comfortable.
Summer is Calais's best season of the year to visit on our travel score. For the whole year in context, see Calais's year-round climate.
- Avg daytime high
- 18°C
- warmest season of the year
- Avg overnight low
- 15°C
- Rainfall
- 165 mm
- 28 wet days
- Avg wind
- 20 km/h
- Travel score
- 5.8
- best season of the year
- Months
- Jun · Jul · Aug
Temperature in Calais in Summer
Over the season highs climb from about 15°C in early June to 19°C by late August.
A typical summer day in Calais reaches about 18°C and drops to 15°C overnight. The warmest of the three months is August, the coolest June.
How summer really feels in Calais
Once humidity and wind are folded in, summer brings about 0 days that feel above 32°C and 0 that feel at or below 0°C.
summer sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Calais weather by month
How the three summer months (June, July and August) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 8° / 5° | 79 | 14.3 | 0.8 | 8.2 | 1.0 |
| Feb | 7° / 5° | 60 | 11.4 | 1 | 9.7 | 1.0 |
| Mar | 9° / 6° | 51 | 10.5 | 0.5 | 11.5 | 1.7 |
| Apr | 11° / 8° | 45 | 9.3 | 0 | 13.5 | 2.7 |
| May | 14° / 10° | 51 | 9.8 | 0 | 15.3 | 3.9 |
| Jun | 16° / 13° | 49 | 8.7 | 0 | 16.2 | 5.2 |
| Jul | 19° / 15° | 51 | 9.6 | 0 | 15.8 | 6.1 |
| Aug | 19° / 16° | 65 | 10 | 0 | 14.3 | 6.2 |
| Sep | 18° / 14° | 68 | 11.2 | 0 | 12.4 | 5.5 |
| Oct | 15° / 12° | 96 | 14.3 | 0 | 10.4 | 3.9 |
| Nov | 11° / 8° | 101 | 16.4 | 0.2 | 8.7 | 2.3 |
| Dec | 9° / 6° | 94 | 15 | 0.7 | 7.8 | 1.4 |
Cloud cover in Summer
The sky is clear or mostly clear about 28% of the time across summer.
Chance of precipitation in Summer
Calais gets around 165 mm of rain over 28 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels comfortable — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 20 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 16 hours in early June to 13 h 24 min by late August. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 5.4 kWh/m².
Is summer a good time to visit Calais?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a reasonable time to visit Calais for sightseeing.
What to pack for Calais in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Calais sees daytime highs around 18°C and nights near 15°C. Worth packing: a warm layer, rain gear and sun protection. About 28 days see rain.
Sea temperature near Calais in Summer
The nearest coast averages about 16°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 18 km away) is warmest in August at about 18°C and coldest in March near 8°C.
The water stays below 20°C all year — cool enough that most swimmers want a wetsuit.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 9 | 8 | 8 | 9 | 11 | 14 | 16 | 18 | 17 | 16 | 13 | 11 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Cool | Cool | Cool | Cool | Bracing | Bracing |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 9 | Bracing |
| Feb | 8 | Bracing |
| Mar | 8 | Bracing |
| Apr | 9 | Bracing |
| May | 11 | Bracing |
| Jun | 14 | Bracing |
| Jul | 16 | Cool |
| Aug | 18 | Cool |
| Sep | 17 | Cool |
| Oct | 16 | Cool |
| Nov | 13 | Bracing |
| Dec | 11 | Bracing |
UV index in Calais in Summer
Clear-sky midday UV across summer averages around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Calais peaks around June 22 at about 6 (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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 1 | 3 | 4 | 6 | 7 | 6 | 7 | 4 | 2 | 1 | 1 |
| Level | Low | Low | Moderate | Moderate | High | High | High | High | Moderate | Moderate | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 1 | Low |
| Mar | 3 | Moderate |
| Apr | 4 | Moderate |
| May | 6 | High |
| Jun | 7 | High |
| Jul | 6 | High |
| Aug | 7 | High |
| Sep | 4 | Moderate |
| Oct | 2 | Moderate |
| Nov | 1 | Low |
| Dec | 1 | Low |
Where is Calais?
Calais sits at 51.0°N, 1.9°E, 6 m above sea level, in France. The nearest listed city is Boulogne-sur-Mer, 30 km away.
Topography around Calais
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Calais.
Within 3 km, the terrain around Calais has only modest variations in elevation — a maximum elevation change of 20 m around an average of 3 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 250 m; within 80 km, significant variations in elevation — a maximum elevation change of 290 m.
The land around Calais is covered by artificial surfaces (48%) and grassland (23%) within 3 km, water (45%) and cropland (30%) within 16 km, and water (47%) and cropland (30%) within 80 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
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 Calais (50.9519°, 1.8563°, elevation 6 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.