ERA5 almanac — 8 years of real data

Maui in August

Maui in August: 32% of days see measurable rain, 80°F average high, 43% of days historically clear (n=248, ERA5 2018–2025).

Maui in August is a mixed month for sun: 43% of days historically clear (n=248, avg high 80°F). The outcome varies year to year — check the early/late split below. 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 Maui 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 August

Clear-sky percentage for Maui in August, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period	% Clear days	Sample (n)	Avg high
Early August 1st–15th	46%	n=120	80°F
Late August 16th–end	41%	n=128	80°F
Full month average	43%	n=248	80°F

Sunshine & warmth in August

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 Maui in August. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period	Warm & sunny (≥72°F, >6 h sun)	Sample (n)
Early August 1st–15th	100%	n=120
Late August 16th–end	95%	n=128
Full month average	97%	n=248

12.6 h median sunshine per day 95% of days exceed 8 h sunshine 32% of days see ≥ 1 mm rain — rain is not hidden

Comparison (old vs new): WMO-code “clear” bar: 43%. Sunshine-based “warm & sunny”: 97%. The 54-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

Maui in August is genuinely mixed: 43% of days historically clear (n=248), avg high 80°F — more cloudy than clear. The outcome varies year to year; don't book if you need guaranteed sun.

Every month in Maui

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

Historical clear-sky % for Maui, all months, ERA5 2018–2025.
Month	% Clear	Sample (n)
January	25%	n=248	All destinations →
February	16%	n=226	All destinations →
March	15%	n=248	All destinations →
April	19%	n=240	All destinations →
May	26%	n=248	All destinations →
June	40%	n=240	All destinations →
July	33%	n=248	All destinations →
August ← this page	43%	n=248	All destinations →
September	34%	n=240	All destinations →
October	28%	n=248	All destinations →
November	30%	n=240	All destinations →
December	30%	n=248	All destinations →

Frequently asked

Does it rain in Maui in August?

Sometimes. Maui sees measurable rain on 32% of days in August historically (n=248 days, ERA5 2018–2025) — not frequent enough to plan around, but not negligible either.

Is Maui good for sun in August?

It's mixed. Maui in August is clear on 43% of days historically (avg high 80°F, n=248 days, ERA5 2018–2025) — the outcome varies year to year.

How Maui compares in August

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

→ Maui vs Honolulu in August — Honolulu is 31% clear historically
→ Maui vs Lanai in August — Lanai is 26% clear historically

→ Maui live forecast — this week’s actual 7-day weather, not historical
→ Best destinations in August — all destinations ranked by August 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.