Calais weather in May

In May, Calais sees average daytime highs of 14°C and overnight lows near 10°C, with 51 mm of rain across 9.8 wet days and about 15.3 hours of daylight. It is the 6th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 12°C in the first days to 15°C by the end. The sky is clear or mostly clear about 26% of the time in May, and the air most often feels dry.

Daylight stretches from about 14 h 30 min at the start of May to 15 h 54 min by month's end. Set against the rest of the year, May is Calais's 5th-clearest and 9th-windiest month. For the whole year in context, see Calais's year-round climate.

Daytime high
14°
6th warmest
Overnight low
10°
7th coldest
Rainfall
51 mm
9.8 wet days
Daylight
15 h 18 min
5:10 AM – 8:28 PM
Cloud cover
62%
5th clearest
Wind
21 km/h
9th windiest
Solar energy
5.4 kWh/m²
Travel score
3.9
out of 10

Calais is commune in Pas-de-Calais, France.

Air quality
Moderate
PM2.5 10.2 µg/m³ · 2019
Density
2,222/km²
people per km²

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 12°C in the first days to 15°C by the end.

A typical May day in Calais reaches about 14°C in the afternoon and slips back to 10°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 11°C and 17°C. Set against its neighbours, May runs about 3°C warmer than April and about 3°C cooler than June.

10°15°20°151015202531
Avg high (°C)Avg low (°C)
1129
2129
3129
4129
5139
6139
71310
81310
91310
101310
111310
121310
131310
141310
151310
161410
171411
181411
191411
201411
211411
221411
231411
241411
251511
261511
271511
281512
291512
301512
311512

How May really feels in Calais

Once humidity and wind are folded in, May averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

May 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 May compares with the rest of the year at a glance. May is the 6th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 7914.30.88.21.0
Feb / 6011.419.71.0
Mar / 5110.50.511.51.7
Apr11° / 459.3013.52.7
May14° / 10°519.8015.33.9
Jun16° / 13°498.7016.25.2
Jul19° / 15°519.6015.86.1
Aug19° / 16°6510014.36.2
Sep18° / 14°6811.2012.45.5
Oct15° / 12°9614.3010.43.9
Nov11° / 10116.40.28.72.3
Dec / 94150.77.81.4

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 26% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 17% of May, with mostly cloudy or overcast conditions the remaining 57%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14159
24159
34159
44258
54258
64258
74159
84258
94258
104258
114258
124258
134258
144258
154357
164456
174456
184456
194456
204456
214456
224456
234456
244456
254357
264357
274357
284357
294357
304357
314357

Chance of precipitation in May

Any precipitation

Calais gets around 51 mm of rain over 9.8 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 32% and peaks near 35% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
135
235
334
434
533
632
732
831
931
1031
1131
1231
1331
1432
1532
1632
1732
1833
1933
2033
2133
2233
2333
2433
2532
2632
2732
2832
2932
3032
3132

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

Most of May feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, May lands in the dry band about 97% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
11000
21000
31000
41000
51000
61000
7991
8991
9991
10991
11991
12991
13991
14991
15982
16982
17982
18982
19973
20973
21964
22964
23955
24946
25946
26937
27928
28928
29919
309010
318911

Wind in May

Winds average 21 km/h in May.

Across May, daily wind ranges from about 20 km/h on the calmest days to 21 km/h at its breeziest. It stays fairly steady from day to day.

0510152025151015202531
Wind speed (km/h)Feels
121breezy
221breezy
321breezy
421breezy
521breezy
621breezy
721breezy
821breezy
921breezy
1021breezy
1121breezy
1221breezy
1321breezy
1421breezy
1521breezy
1621breezy
1721breezy
1820breezy
1920breezy
2020breezy
2120breezy
2220breezy
2320breezy
2420breezy
2520light breeze
2620light breeze
2720light breeze
2820light breeze
2920light breeze
3020light breeze
3120light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 14 h 30 min at the start of May to 15 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 84 minutes over May. Sunrise moves from 5:35 AM to 4:52 AM, and sunset from 8:04 PM to 8:48 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.55:358:04
214.55:348:06
314.65:328:07
414.75:308:09
514.75:288:11
614.85:268:12
714.85:248:14
814.95:238:15
914.95:218:17
1015.05:198:18
1115.05:188:20
1215.15:168:22
1315.15:158:23
1415.25:138:25
1515.25:128:26
1615.35:108:28
1715.35:098:29
1815.45:078:31
1915.45:068:32
2015.55:048:33
2115.55:038:35
2215.65:028:36
2315.65:018:38
2415.75:008:39
2515.74:588:40
2615.74:578:41
2715.84:568:43
2815.84:558:44
2915.84:548:45
3015.94:538:46
3115.94:528:48

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.4 kWh/m².

For context, solar energy here swings from a low near 0.68 kWh/m² to a high of 5.74 kWh/m² in June across the year — May's 5.4 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
35.0Bright
45.1Bright
55.1Bright
65.1Bright
75.2Bright
85.2Bright
95.2Bright
105.2Bright
115.3Bright
125.3Bright
135.3Bright
145.3Bright
155.4Bright
165.4Bright
175.4Bright
185.4Bright
195.5Bright
205.5Bright
215.5Bright
225.5Bright
235.5Bright
245.5Bright
255.5Bright
265.5Bright
275.5Bright
285.6Bright
295.6Bright
305.6Bright
315.6Bright
Planning a trip in May

Is May a good time to visit Calais?

Our two travel scores rate May for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

3.9
Sightseeing
5th-best month of the year
0.0
Beach & pool
6th-best month of the year

May is a weaker month for outdoor sightseeing in Calais.

What to pack for Calais in May

From May's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In May, Calais sees daytime highs around 14°C and nights near 10°C. Worth packing: a warm layer, rain gear, sun protection and a windbreaker. About 10 days see rain.

a warm layerrain gearsun protectiona windbreaker

Sea temperature near Calais in May

The nearest coast averages about 11°C in May — 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.

5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°C)Comfort
Jan9Bracing
Feb8Bracing
Mar8Bracing
Apr9Bracing
May11Bracing
Jun14Bracing
Jul16Cool
Aug18Cool
Sep17Cool
Oct16Cool
Nov13Bracing
Dec11Bracing

UV index in Calais in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowJun 22UV 6Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr4Moderate
May6High
Jun7High
Jul6High
Aug7High
Sep4Moderate
Oct2Moderate
Nov1Low
Dec1Low
Location & terrain

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.

3 km
20 m
16 km
250 m
80 km
290 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
May weather nearby: Boulogne-sur-Mer 30 km · Grande-Synthe 32 km · Outreau 33 km · Saint-Pol-sur-Mer 35 km · Saint-Omer 36 km · Dunkirk 38 km · Coudekerque-Branche 38 km · Dover 43 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 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. 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).