United Kingdom · 1991–2020

Best time to visit
Harlech.

July leads for comfortable weather in Harlech: typically 18.4°C by day, 10.1°C at night, with 83 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortJuly

Typical high18.4°C

Typical low10.1°C

Rain in July83 mm

Comfort

July

July · August · June

56climate match

Beach

July

July · August · June

18climate match

Outdoors

July

July · August · June

74climate match

The weakest month is January, scoring 5 against July’s 56 — days reach only 6.3°C, 18° 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

56.3° / 0°

Feb

56.6° / 0.1°

Mar

58.5° / 0.9°

Apr

1911.2° / 2.6°

May

3514.4° / 5.2°

Jun

4816.6° / 8.1°

Jul

5618.4° / 10.1°

Aug

5217.8° / 9.9°

Sep

4015.8° / 7.7°

Oct

1512.2° / 5.3°

Nov

59° / 2.6°

Dec

56.8° / 0.5°

Monthly climate evidence for Harlech — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 2 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	6.3°C	0°C	147 mm	18	7.9°C	8 h 06	5	Strong coverage
February	6.6°C	0.1°C	122 mm	15.5	7.3°C	9 h 46	5	Strong coverage
March	8.5°C	0.9°C	100 mm	15	7.5°C	11 h 40	5	Strong coverage
April	11.2°C	2.6°C	89 mm	13.5	9.3°C	13 h 52	19	Strong coverage
May	14.4°C	5.2°C	83 mm	13.1	11.7°C	15 h 46	35	Strong coverage
June	16.6°C	8.1°C	87 mm	12.1	14.4°C	16 h 52	48	Strong coverage
July	18.4°C	10.1°C	83 mm	13.3	16.2°C	16 h 25	56	Strong coverage
August	17.8°C	9.9°C	95 mm	14.6	17.1°C	14 h 44	52	Strong coverage
September	15.8°C	7.7°C	105 mm	14.1	16.2°C	12 h 36	40	Strong coverage
October	12.2°C	5.3°C	146 mm	17.2	14.1°C	10 h 29	15	Strong coverage
November	9°C	2.6°C	153 mm	19.6	11.5°C	8 h 36	5	Strong coverage
December	6.8°C	0.5°C	179 mm	19.2	9.5°C	7 h 37	5	Strong coverage

What has changed

Harlech runs +1.4°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

+0.9

Feb

+2.3

Mar

+2.0

Apr

+1.9

May

+1.2

Jun

+1.2

Jul

+0.8

Aug

+0.7

Sep

+1.1

Oct

+0.9

Nov

+1.6

Dec

+1.8

July daytime highs, 2011–2025. Last recorded: 18.9°C.

Records at ALWEN, 1960–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	14.8°C9 Jan 1998	-16.7°C7 Jan 1970	50 mm15 Jan 2011	281 mm1999 · driest 8 mm in 1997	65
February	19.7°C24 Feb 2019	-16.7°C16 Feb 1969	65 mm15 Feb 2020	354 mm2020 · driest 19 mm in 1986	65
March	21.1°C28 Mar 1965	-17.2°C2 Mar 1965	47 mm14 Mar 1982	223 mm1981 · driest 0 mm in 1996	63
April	24.3°C19 Apr 2019	-9.5°C11 Apr 1978	43 mm2 Apr 1962	195 mm2012 · driest 9 mm in 1980	65
May	24.6°C19 May 2020	-6.1°C1 May 1960	50 mm3 May 2021	233 mm2021 · driest 13 mm in 2020	62
June	30.0°C28 Jun 1976	-2.5°C5 Jun 1973	60 mm25 Jun 2007	199 mm2007 · driest 9 mm in 2018	64
July	33.6°C18 Jul 2022	-1.1°C6 Jul 1962	62 mm31 Jul 1972	214 mm2007 · driest 21 mm in 1979	65
August	30.8°C1 Aug 1990	-1.1°C10 Aug 1960	72 mm25 Aug 1986	197 mm1986 · driest 13 mm in 1976	63
September	28.0°C1 Sep 1999	-3.3°C30 Sep 1969	80 mm11 Sep 1976	296 mm1976 · driest 16 mm in 2014	62
October	23.2°C8 Oct 2023	-5.0°C13 Oct 1964	67 mm14 Oct 1976	274 mm1967 · driest 38 mm in 1969	62
November	18.5°C1 Nov 2015	-12.0°C29 Nov 2010	72 mm26 Nov 2012	372 mm2009 · driest 58 mm in 1988	63
December	14.2°C30 Dec 2021	-16.8°C13 Dec 1981	64 mm25 Dec 2015	423 mm2015 · driest 26 mm in 1963	63

Typical days per month at ALWEN, 1991–2020
Month	Days 25°C+	Frost nights	Heavy rain (10 mm+)
January	0	13	5
February	0	12	4
March	0	12	3
April	0	7	3
May	0	3	2
June	<1	<1	3
July	2	0	2
August	<1	0	3
September	<1	<1	4
October	0	2	5
November	0	6	5
December	0	13	7

How often, not how much — every day in ALWEN’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	0%	58%	15%	75%	3.8–7.5°C
February	0%	53%	13%	70%	3.5–7.8°C
March	<1%	50%	9%	66%	5.4–9.9°C
April	1%	45%	8%	59%	8.7–12.8°C
May	7%	44%	7%	58%	11.8–16.1°C
June	16%	40%	8%	53%	14.2–17.9°C
July	21%	40%	7%	56%	15.8–20.0°C
August	16%	45%	9%	62%	16.0–19.7°C
September	6%	47%	12%	66%	13.8–16.7°C
October	<1%	55%	14%	74%	10.5–13.7°C
November	0%	62%	17%	80%	6.7–10.0°C
December	0%	60%	19%	77%	4.5–8.0°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.

1960Each stripe is one year’s mean temperature against the 48-year average. Warmest: 2006. Coolest: 1963.2020

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 2647471
NOAA station: UKE00105882 · ALWEN
Station distance: 43.4 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 26 usable years
Daylight: Calculated from latitude 52.86°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 2 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 ALWEN is what differs

Colwyn Bay→Llandudno→Abergele→Deganwy→Blaenau-Ffestiniog→Conwy→

Or put two places side by side: Harlech vs Colwyn Bay

Best time to visitHarlech.

July

July

July

The whole year,without the guesswork.

Harlech runs +1.4°Con the 1961–1990 baseline.

Nearby, measured,and named.

Best time to visit
Harlech.

The whole year,
without the guesswork.

Harlech runs +1.4°C
on the 1961–1990 baseline.

Nearby, measured,
and named.