ERA5 almanac — 8 years of real data

London in June

London in June: 33% of days see measurable rain, 70°F average high, 24% of days historically clear (n=240, ERA5 2018–2025).

London in June is historically a poor month for sun: only 24% of days clear across 8 years (n=240, avg high 70°F). July is the clearest month for London historically. Historical average, not a forecast.

What you are reading: 8-year historical averages from the ERA5 reanalysis, not a forecast. A month that is historically 90% clear can still be overcast on your specific trip. For this week’s actual forecast, see the live London page. Both can be true at once: “historically strong in this month; this particular week is not.” We label which is which.

Early vs. Late June

Clear-sky percentage for London in June, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period	% Clear days	Sample (n)	Avg high
Early June 1st–15th	16%	n=120	70°F
Late June 16th–end	32%	n=120	70°F
Full month average	24%	n=240	70°F

Sunshine & warmth in June

A second measure using actual sunshine hours (ERA5 sunshine_duration), not the daily weather code. A Lowcountry day with 12 hours of sun and a 25-minute afternoon storm is counted below as a warm, sunny day — because it was. How we define this.

Sunshine-based metrics for London in June. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period	Warm & sunny (≥72°F, >6 h sun)	Sample (n)
Early June 1st–15th	27%	n=120
Late June 16th–end	49%	n=120
Full month average	38%	n=240

13.8 h median sunshine per day 80% of days exceed 8 h sunshine 33% of days see ≥ 1 mm rain — rain is not hidden

Comparison (old vs new): WMO-code “clear” bar: 24%. Sunshine-based “warm & sunny”: 38%. The 14-point gap is from brief afternoon convective storms that stamp the whole day as “rain” in the WMO code but leave the bulk of the sunshine untouched.

Bottom line

London is mostly overcast in June historically: only 24% of days are clear across 8 years (n=240), avg high 70°F. If you want sun in London, July is historically much better. Most visitors this month will see more clouds than sun.

→ See all destinations in July — historically the best month for sun in London.

Every month in London

Compare across all months with data. Numbers are historical clear-sky %.

Historical clear-sky % for London, all months, ERA5 2018–2025.
Month	% Clear	Sample (n)
January	0%	n=248	All destinations →
February	0%	n=226	All destinations →
March	0%	n=248	All destinations →
April	5%	n=240	All destinations →
May	8%	n=248	All destinations →
June ← this page	24%	n=240	All destinations →
July	28%	n=248	All destinations →
August	28%	n=248	All destinations →
September	14%	n=240	All destinations →
October	2%	n=248	All destinations →
November	0%	n=240	All destinations →
December	0%	n=248	All destinations →

Frequently asked

Does it rain in London in June?

Sometimes. London sees measurable rain on 33% of days in June historically (n=240 days, ERA5 2018–2025) — not frequent enough to plan around, but not negligible either.

Is London good for sun in June?

Not usually. London is historically overcast in June: only 24% of days are clear (avg high 70°F, n=240 days, ERA5 2018–2025). July is historically far better for sun here.

How London compares in June

Head-to-head clear-sky comparisons against destinations travelers plausibly weigh against London this month — same passport tier, similar flight distance, both sides from the same 8-year ERA5 record.

→ London vs Amsterdam in June — Amsterdam is 22% clear historically
→ London vs Paris in June — Paris is 33% clear historically
→ London vs Venice in June — Venice is 54% clear historically

→ London live forecast — this week’s actual 7-day weather, not historical
→ Best destinations in June — all destinations ranked by June clear-sky %
→ All destinations
→ Raw data (JSON) — buckets, n, source

All percentages are historical averages from the ERA5 reanalysis via Open-Meteo, 8 full years (2018–2025). “Clear” means avg high ≥ 72 °F, precipitation < 1 mm, and a non-precipitation weather code. This is history, not a forecast. The live 7-day outlook for any destination is on its own page and may differ from the long-run average. Data from Open-Meteo.