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SunnyDays

ERA5 almanac — 8 years of real data

Aruba in May

Aruba in May: 18% of days see measurable rain, 87°F average high, 39% of days historically clear (n=248, ERA5 2018–2025).

Aruba in May is historically a poor month for sun: only 39% of days clear across 8 years (n=248, avg high 87°F). 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 Aruba 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 May

Clear-sky percentage for Aruba in May, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early May
1st–15th		 34% n=120 87°F
Late May
16th–end		 43% n=128 87°F
Full month average 39% n=248 87°F

Sunshine & warmth in May

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 Aruba in May. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early May
1st–15th		 96% n=120
Late May
16th–end		 98% n=128
Full month average 97% n=248
12.1 h median sunshine per day 95% of days exceed 8 h sunshine 18% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 39%. Sunshine-based “warm & sunny”: 97%. The 58-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

Aruba is mostly overcast in May historically: only 39% of days are clear across 8 years (n=248), avg high 87°F. Most visitors this month will see more clouds than sun.

Every month in Aruba

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

Historical clear-sky % for Aruba, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 24% n=248 All destinations →
February 22% n=226 All destinations →
March 33% n=248 All destinations →
April 33% n=240 All destinations →
May ← this page 39% n=248 All destinations →
June 30% n=240 All destinations →
July 22% n=248 All destinations →
August 24% n=248 All destinations →
September 32% n=240 All destinations →
October 14% n=248 All destinations →
November 6% n=240 All destinations →
December 12% n=248 All destinations →

Frequently asked

Does it rain in Aruba in May?

Rarely. Only 18% of days in Aruba see measurable rain in May, based on 8 years of ERA5 historical data (n=248 days, 2018–2025). This is a historical average, not a forecast.

Is Aruba good for sun in May?

It's mixed. Aruba in May is clear on 39% of days historically (avg high 87°F, n=248 days, ERA5 2018–2025) — the outcome varies year to year.

How Aruba compares in May

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

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.