Castro-Urdiales weather in May

In May, Castro-Urdiales sees average daytime highs of 17°C and overnight lows near 13°C, with 69 mm of rain across 12.7 wet days and about 14.5 hours of daylight. It is the 6th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 16°C in the first days to 18°C by the end. The sky is clear or mostly clear about 23% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 54 min at the start of May to 14 h 54 min by month's end. Set against the rest of the year, May is Castro-Urdiales's 6th-clearest and 8th-windiest month. For the whole year in context, see Castro-Urdiales's year-round climate.

Daytime high
17°
6th warmest
Overnight low
13°
7th coldest
Rainfall
69 mm
12.7 wet days
Daylight
14 h 30 min
5:54 AM – 8:24 PM
Cloud cover
62%
6th clearest
Wind
14 km/h
8th windiest
Solar energy
5.75 kWh/m²
Travel score
5.1
out of 10

Castro-Urdiales is capital of Castro-Urdiales Municipality, Spain.

Air quality
Good
PM10 15.1 µg/m³ · 2019

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 16°C in the first days to 18°C by the end.

A typical May day in Castro-Urdiales reaches about 17°C in the afternoon and slips back to 13°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 14°C and 20°C. Set against its neighbours, May runs about 2°C warmer than April and about 3°C cooler than June.

10°15°20°25°151015202531
Avg high (°C)Avg low (°C)
11612
21612
31612
41612
51612
61612
71612
81612
91613
101613
111713
121713
131713
141713
151713
161713
171713
181713
191713
201714
211714
221814
231814
241814
251814
261814
271814
281814
291814
301815
311815

Castro-Urdiales 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 daysDaylight (hours)Travel score
Jan12° / 119159.22.9
Feb12° / 10313.510.22.9
Mar14° / 10°9813.211.63.7
Apr15° / 11°8913.813.24.0
May17° / 13°6912.714.55.1
Jun20° / 16°569.915.26.2
Jul22° / 18°469.114.96.9
Aug23° / 19°499.413.87.0
Sep21° / 17°6610.912.36.4
Oct19° / 15°10313.810.85.5
Nov15° / 12°15216.19.53.9
Dec13° / 10°11714.98.83.3

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 23% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 16% of May, with mostly cloudy or overcast conditions the remaining 61%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13862
23763
33763
43763
53664
63664
73664
83664
93565
103565
113664
123763
133664
143664
153763
163961
173862
183961
194060
204159
214258
224357
234357
244456
254456
264456
274357
284357
294357
304258
314258

Chance of precipitation in May

Any precipitation

Castro-Urdiales gets around 69 mm of rain over 12.7 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 41% and peaks near 47% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
147
247
347
447
546
646
745
845
944
1044
1143
1243
1342
1441
1541
1640
1740
1839
1939
2038
2138
2238
2337
2437
2537
2637
2737
2837
2937
3038
3138

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 69% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
187130
286140
384160
483170
582180
681190
780200
879210
979210
1078220
1177230
1276240
1376240
1475250
1574260
1672271
1771281
1870291
1967312
2066322
2164333
2262344
2359365
2457376
2555387
2653407
2751418
2849419
29484210
30474211
31464212

Wind in May

Winds average 14 km/h in May.

Across May, daily wind ranges from about 13 km/h on the calmest days to 15 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
115light breeze
215light breeze
314light breeze
414light breeze
514light breeze
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1414light breeze
1514light breeze
1614light breeze
1714light breeze
1814light breeze
1913light breeze
2013light breeze
2113light breeze
2213light breeze
2313light breeze
2413light breeze
2513light breeze
2613light breeze
2713light breeze
2813light breeze
2913light breeze
3013light breeze
3113light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 54 min at the start of May to 14 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 60 minutes over May. Sunrise moves from 6:13 AM to 5:42 AM, and sunset from 8:07 PM to 8:39 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.96:138:07
213.96:128:08
314.06:118:09
414.06:098:10
514.16:088:11
614.16:068:13
714.16:058:14
814.26:048:15
914.26:038:16
1014.36:018:17
1114.36:008:18
1214.35:598:19
1314.45:588:21
1414.45:578:22
1514.55:558:23
1614.55:548:24
1714.55:538:25
1814.65:528:26
1914.65:518:27
2014.65:508:28
2114.75:498:29
2214.75:498:30
2314.75:488:31
2414.85:478:32
2514.85:468:33
2614.85:458:34
2714.85:448:35
2814.95:448:36
2914.95:438:37
3014.95:428:38
3114.95:428:39

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.75 kWh/m².

For context, solar energy here swings from a low near 1.4 kWh/m² to a high of 6.12 kWh/m² in June across the year — May's 5.75 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.3Bright
25.3Bright
35.3Bright
45.4Bright
55.4Bright
65.4Bright
75.5Bright
85.5Bright
95.5Bright
105.5Bright
115.6Bright
125.6Bright
135.6Bright
145.7Bright
155.7Bright
165.8Bright
175.8Bright
185.8Bright
195.8Bright
205.9Bright
215.9Bright
225.9Bright
235.9Bright
246.0Bright
256.0Bright
266.0Bright
276.0Bright
286.0Bright
296.0Bright
306.0Bright
316.0Bright
Planning a trip in May

Is May a good time to visit Castro-Urdiales?

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

5.1
Sightseeing
6th-best month of the year
1.2
Beach & pool
6th-best month of the year

May is a reasonable time to visit Castro-Urdiales for sightseeing.

What to pack for Castro-Urdiales in May

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

In May, Castro-Urdiales sees daytime highs around 17°C and nights near 13°C. Worth packing: rain gear and sun protection. About 13 days see rain.

rain gearsun protection

Sea temperature near Castro-Urdiales in May

The nearest coast averages about 15°C in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 22°C and coldest in February near 13°C.

It's comfortable for a long swim from Jul 11 to Sep 21 — about 2.4 months when the water holds above 20°C.

10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingcomfortable to swim
Sea temperature (°C)Comfort
Jan13Bracing
Feb13Bracing
Mar13Bracing
Apr13Bracing
May15Cool
Jun18Cool
Jul21Refreshing
Aug22Refreshing
Sep20Refreshing
Oct18Cool
Nov16Cool
Dec14Bracing

UV index in Castro-Urdiales 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 Castro-Urdiales 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
Jan2Low
Feb2Low
Mar5Moderate
Apr6High
May6High
Jun8Very high
Jul9Very high
Aug8Very high
Sep5High
Oct4Moderate
Nov2Low
Dec1Low
Location & terrain

Where is Castro-Urdiales?

Castro-Urdiales sits at 43.4°N, 3.2°W, 18 m above sea level, in Spain. The nearest listed city is Santurtzi, 16 km away.

Topography around Castro-Urdiales

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

Within 3 km, the terrain around Castro-Urdiales has significant variations in elevation — a maximum elevation change of 455 m around an average of 60 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 851 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,676 m.

The land around Castro-Urdiales is covered by water (46%) and trees (30%) within 3 km, water (50%) and trees (35%) within 16 km, and trees (37%), water (35%) and grassland (20%) within 80 km.

3 km
455 m
16 km
851 m
80 km
1,676 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Santurtzi 16 km · Getxo 17 km · Algorta 17 km · Portugalete 18 km · Sestao 19 km · Leioa 20 km · Barakaldo 21 km · Erandio 22 km

Spain travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / F
230 V · 50 Hz
Prices
≈ 65% of US
price level, 2025
GDP per capita
$38,627
2025
Happiness
6.5 / 10
World Happiness, 2025
Safe drinking water
99%
of population, 2024
Homicide rate
0.7
per 100k, 2023
Road deaths
3.9
per 100k/yr, 2019
Income group
High
World Bank
English
Moderate
EF EPI 540
Religion
Roman Catholic 58%atheist 16%agnostic 11%non-believer 11%

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 Castro-Urdiales (43.3828°, -3.2204°, elevation 18 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).