Bermeo weather in September

In September, Bermeo sees average daytime highs of 20°C and overnight lows near 18°C, with 74 mm of rain across 11.4 wet days and about 12.3 hours of daylight. It is the 3rd-warmest and 8th-wettest month of the year here.

Day-to-day highs hold fairly steady near 20°C through the month. The sky is clear or mostly clear about 36% of the time in September, and the air most often feels comfortable.

Daylight stretches from about 13 hours at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Bermeo's 3rd-clearest and 9th-windiest month. For the whole year in context, see Bermeo's year-round climate.

Daytime high
20°
3rd warmest
Overnight low
18°
10th coldest
Rainfall
74 mm
11.4 wet days
Daylight
12 h 18 min
6:56 AM – 7:14 PM
Cloud cover
52%
3rd clearest
Wind
16 km/h
9th windiest
Solar energy
4.27 kWh/m²
Travel score
6.2
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 20°C through the month.

A typical September day in Bermeo reaches about 20°C in the afternoon and slips back to 18°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 18°C and 23°C. Set against its neighbours, September runs about 1°C cooler than August and about 2°C warmer than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
12119
22119
32119
42119
52119
62119
72119
82119
92119
102119
112118
122018
132018
142018
152018
162018
172018
182018
192018
202018
212018
222018
232018
242018
252017
262017
272017
281917
291917
301917

Bermeo weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan12° / 10°14115.89.12.8
Feb12° / 12414.410.22.6
Mar13° / 10°11013.411.63.2
Apr14° / 11°9513.913.23.6
May16° / 14°7012.314.54.7
Jun18° / 17°5710.215.26.0
Jul20° / 19°519.514.96.7
Aug21° / 20°5510.113.86.8
Sep20° / 18°7411.412.36.2
Oct18° / 16°1131410.85.4
Nov15° / 13°18016.99.53.8
Dec13° / 11°14115.78.83.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 36% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 22% of September, with mostly cloudy or overcast conditions the remaining 43%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16337
26436
36436
46436
56337
66337
76337
86238
96238
106139
116040
126040
135941
145941
155743
165644
175644
185545
195545
205446
215446
225347
235347
245248
255248
265248
275149
285149
295050
305050

Chance of precipitation in September

Any precipitation

Bermeo gets around 74 mm of rain over 11.4 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 39% and peaks near 44% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
135
235
335
435
535
635
735
836
936
1036
1137
1237
1338
1438
1539
1639
1740
1840
1941
2041
2141
2241
2341
2442
2542
2643
2743
2843
2944
3044

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the comfortable band about 33% of days. Sticky, muggy-or-worse air turns up on roughly 12% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
111303721
212313621
313313520
413323520
514323420
615333419
715333319
816333318
917333218
1018333217
1119333216
1220333216
1321323215
1422323214
1523323213
1624323212
1725323211
1826323210
192732329
202733328
212833328
222833317
232834316
242934316
252934315
263035315
273035314
283135314
293235303
303335293

Wind in September

Winds average 16 km/h in September.

Across September, daily wind ranges from about 15 km/h on the calmest days to 17 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
115light breeze
215light breeze
315light breeze
415light breeze
515light breeze
615light breeze
715light breeze
816light breeze
916light breeze
1016light breeze
1116light breeze
1216light breeze
1316light breeze
1416light breeze
1516light breeze
1616light breeze
1716light breeze
1817light breeze
1917light breeze
2017light breeze
2117light breeze
2217light breeze
2317light breeze
2417light breeze
2517light breeze
2617light breeze
2717light breeze
2817light breeze
2917light breeze
3017light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 hours at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 84 minutes over September. Sunrise moves from 6:39 AM to 7:13 AM, and sunset from 7:42 PM to 6:48 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.06:397:42
213.06:407:40
312.96:427:38
412.96:437:36
512.86:447:35
612.86:457:33
712.76:467:31
812.76:477:29
912.66:487:27
1012.66:507:25
1112.56:517:23
1212.56:527:22
1312.46:537:20
1412.46:547:18
1512.36:557:16
1612.36:567:14
1712.26:587:12
1812.26:597:10
1912.17:007:08
2012.17:017:06
2112.07:027:05
2212.07:037:03
2311.97:057:01
2411.97:066:59
2511.87:076:57
2611.87:086:55
2711.77:096:53
2811.77:106:51
2911.67:126:49
3011.67:136:48

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.27 kWh/m².

For context, solar energy here swings from a low near 1.39 kWh/m² to a high of 6.15 kWh/m² in June across the year — September's 4.27 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.9Bright
24.8Bright
34.8Bright
44.8Bright
54.7Bright
64.7Bright
74.6Bright
84.6Bright
94.5Bright
104.5Bright
114.4Bright
124.4Bright
134.3Bright
144.3Bright
154.3Bright
164.2Bright
174.2Bright
184.1Bright
194.1Bright
204.0Bright
214.0Moderate
223.9Moderate
233.9Moderate
243.8Moderate
253.8Moderate
263.8Moderate
273.7Moderate
283.7Moderate
293.6Moderate
303.6Moderate
Planning a trip in September

Is September a good time to visit Bermeo?

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

6.2
Sightseeing
3rd-best month of the year
3.4
Beach & pool
3rd-best month of the year

September is a reasonable time to visit Bermeo for sightseeing.

What to pack for Bermeo in September

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

In September, Bermeo sees daytime highs around 20°C and nights near 18°C. Worth packing: rain gear. About 11 days see rain.

rain gear

Sea temperature near Bermeo in September

The nearest coast averages about 21°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 24 km away) is warmest in August at about 22°C and coldest in February near 13°C.

It's comfortable for a long swim from Jul 7 to Sep 24 — about 2.6 months when the water holds above 20°C.

10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan13Bracing
Feb13Bracing
Mar13Bracing
Apr13Bracing
May15Cool
Jun18Cool
Jul21Refreshing
Aug22Refreshing
Sep21Refreshing
Oct18Cool
Nov16Cool
Dec14Bracing

UV index in Bermeo in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Bermeo peaks around July 17 at about 8 (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 17UV 8Dec 22UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar5Moderate
Apr6High
May6High
Jun8Very high
Jul8Very high
Aug8Very high
Sep5High
Oct4Moderate
Nov2Low
Dec1Low
Location & terrain

Where is Bermeo?

Bermeo sits at 43.4°N, 2.7°W, 29 m above sea level, in Spain. The nearest listed city is Gernika-Lumo, 12 km away.

Topography around Bermeo

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

Within 3 km, the terrain around Bermeo has significant variations in elevation — a maximum elevation change of 394 m around an average of 70 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 675 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,596 m.

The land around Bermeo is covered by water (47%) and trees (38%) within 3 km, water (52%) and trees (37%) within 16 km, and trees (41%) and water (37%) within 80 km.

3 km
394 m
16 km
675 m
80 km
1,596 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Gernika-Lumo 12 km · Mungia 12 km · Amorebieta 23 km · Galdakao 23 km · Leioa 24 km · Bilbao 24 km · Basauri 24 km · Erandio 24 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 Bermeo (43.4209°, -2.7215°, elevation 29 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).