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Spain · 1991–2020

Best time to visit
Hernani.

July leads for comfortable weather in Hernani: typically 21.9°C by day, 16.2°C at night, with 94 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortJuly

Typical high21.9°C

Typical low16.2°C

Rain in July94 mm

Comfort

July

July · August · September

76climate match

Beach

August

August · July · September

49climate match

Outdoors

June

June · May · July

71climate match

The weakest month is January, scoring 15 against July’s 76 — days reach only 11.2°C, 13° below the 24°C the score treats as ideal.

Month by month

The whole year,
without the guesswork.

The bars show the comfort score. Day and night temperatures come from daily observed highs and lows; rain is the historical monthly estimate.

Jan

1511.2° / 6.1°

Feb

2111.6° / 5.9°

Mar

3213.7° / 7.5°

Apr

3715.1° / 8.7°

May

5218° / 11.4°

Jun

7020.3° / 14.1°

Jul

7621.9° / 16.2°

Aug

7622.9° / 16.8°

Sep

7221.2° / 14.8°

Oct

5218.6° / 12.5°

Nov

2214.2° / 8.8°

Dec

1912° / 6.9°

Monthly climate evidence for Hernani — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 15 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	11.2°C	6.1°C	155 mm	14	12.7°C	9 h 18	15	Strong coverage
February	11.6°C	5.9°C	129 mm	12.3	12.2°C	10 h 26	21	Strong coverage
March	13.7°C	7.5°C	123 mm	12.3	12.5°C	11 h 47	32	Strong coverage
April	15.1°C	8.7°C	128 mm	13.4	13.6°C	13 h 20	37	Strong coverage
May	18°C	11.4°C	126 mm	12.6	15.8°C	14 h 39	52	Strong coverage
June	20.3°C	14.1°C	99 mm	11.2	18.9°C	15 h 22	70	Strong coverage
July	21.9°C	16.2°C	94 mm	10.8	21.2°C	15 h 05	76	Strong coverage
August	22.9°C	16.8°C	112 mm	10.3	22.2°C	13 h 57	76	Strong coverage
September	21.2°C	14.8°C	119 mm	10.8	20.8°C	12 h 27	72	Strong coverage
October	18.6°C	12.5°C	160 mm	11.9	18.3°C	10 h 57	52	Strong coverage
November	14.2°C	8.8°C	206 mm	14.3	15.8°C	9 h 38	22	Strong coverage
December	12°C	6.9°C	158 mm	13.4	13.8°C	8 h 59	19	Strong coverage

What has changed

Hernani runs +1.3°C
on the 1961–1990 baseline.

Each bar compares the 2011–2025 daytime average for that month against the same month in 1961–1990, measured at the same station. Months where the older record is too thin to compare are left blank.

Jan

+0.7

Feb

+0.6

Mar

+1.5

Apr

+2.2

May

+1.2

Jun

+1.6

Jul

+0.7

Aug

+1.4

Sep

+0.5

Oct

+1.2

Nov

+1.4

Dec

+2.0

July daytime highs, 2011–2025. Last recorded: 22.0°C.

Records at SAN SEBASTIAN - IGUELDO, 1916–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	22.6°C1 Jan 2022	-10.0°C6 Jan 1985	76 mm16 Jan 2023	392 mm1979 · driest 6 mm in 1993	100
February	25.6°C27 Feb 2019	-12.1°C3 Feb 1956	84 mm17 Feb 1940	323 mm2016 · driest 9 mm in 1918	99
March	28.0°C17 Mar 1947	-5.5°C6 Mar 1971	85 mm25 Mar 1968	238 mm2008 · driest 3 mm in 1961	101
April	30.5°C25 Apr 1947	-0.4°C12 Apr 1986	70 mm13 Apr 1942	333 mm1986 · driest 8 mm in 1982	101
May	33.4°C22 May 2026	1.6°C1 May 1947	168 mm31 May 1997	265 mm2013 · driest 49 mm in 1987	102
June	38.0°C21 Jun 2003	6.1°C3 Jun 1936	97 mm15 Jun 1933	330 mm1933 · driest 15 mm in 1976	102
July	37.3°C26 Jul 1947	9.4°C8 Jul 1978	116 mm3 Jul 1952	232 mm1932 · driest 15 mm in 1986	100
August	37.1°C21 Aug 2011	9.4°C30 Aug 1977	131 mm23 Aug 2007	337 mm1983 · driest 4 mm in 1937	100
September	36.3°C8 Sep 1966	4.8°C23 Sep 1931	167 mm30 Sep 1949	312 mm1949 · driest 4 mm in 1985	100
October	31.7°C2 Oct 2023	0.8°C29 Oct 1940	135 mm25 Oct 1981	403 mm1974 · driest 16 mm in 1969	100
November	25.6°C8 Nov 2015	-3.4°C23 Nov 1988	87 mm29 Nov 1973	481 mm2019 · driest 16 mm in 1988	100
December	22.0°C2 Dec 1979	-8.4°C24 Dec 1962	113 mm29 Dec 1960	457 mm1960 · driest 16 mm in 2015	100

Typical days per month at SAN SEBASTIAN - IGUELDO, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	0	0	2	5
February	0	0	2	4
March	<1	0	<1	4
April	<1	<1	0	4
May	3	<1	0	4
June	4	1	0	3
July	4	1	0	3
August	6	2	0	3
September	5	<1	0	4
October	2	0	0	5
November	0	0	<1	8
December	0	0	2	5

The best month has moved. On the 1961–1990 numbers the strongest month here was July (scoring 85); on 2011–2025 it is August (86). Both are scored the same way, from the same station — only the climate underneath changed.

How often, not how much — every day in SAN SEBASTIAN - IGUELDO’s record sorted by what it was actually like, rather than averaged
Month	Warm & dry days	Wet days	Washouts	Week with 3+ wet days	Daytime mean has ranged
January	<1%	45%	18%	59%	8.6–13.1°C
February	2%	43%	15%	56%	8.3–14.5°C
March	7%	39%	13%	53%	11.3–15.7°C
April	10%	44%	15%	60%	12.5–17.0°C
May	18%	42%	13%	58%	14.8–19.6°C
June	29%	38%	10%	50%	18.0–22.2°C
July	51%	33%	8%	43%	20.1–23.3°C
August	56%	35%	11%	44%	20.8–24.2°C
September	42%	37%	13%	50%	19.3–23.0°C
October	25%	38%	17%	51%	16.2–20.4°C
November	5%	46%	22%	61%	11.3–16.3°C
December	1%	46%	20%	61%	8.5–13.8°C

A warm and dry day reaches 20°C with under 1 mm of rain; a wet day gets 1 mm or more; a washout gets 10 mm or more. The week column is the share of seven-day stretches in that month, across the station’s whole daily record, that contained three or more wet days — the odds a week-long trip is rained on repeatedly, counted rather than modelled. The last column is the 10th to 90th percentile of that month’s daytime average across individual years: a narrow band means the average is what you will get, a wide one means the average is a midpoint between years that felt quite different.

1918Each stripe is one year’s mean temperature against the 83-year average. Warmest: 2022. Coolest: 1956.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 3120811
NOAA station: SP000008027 · SAN SEBASTIAN - IGUELDO
Station distance: 6.9 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 29 usable years
Daylight: Calculated from latitude 43.27°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 15 km from the place centre. A sheltered bay can run warmer than the open sea it is measured from.
Important limit: Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.

These places read the same station, so their numbers are identical — distance from SAN SEBASTIAN - IGUELDO is what differs

Donostia / San Sebastián→Zarautz→Tolosa→Oria→Lasarte→Pasaia→

Or put two places side by side: Hernani vs Donostia / San Sebastián

Best time to visitHernani.