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SunnyDays

ERA5 almanac — 8 years of real data

Cayman Islands in April

Cayman Islands in April: 58% of days see measurable rain, 84°F average high, 10% of days historically clear (n=240, ERA5 2018–2025).

Cayman Islands in April is historically a poor month for sun: only 10% of days clear across 8 years (n=240, avg high 84°F). January is the clearest month for Cayman Islands 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 Cayman Islands 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 April

Clear-sky percentage for Cayman Islands in April, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early April
1st–15th		 15% n=120 84°F
Late April
16th–end		 5% n=120 84°F
Full month average 10% n=240 84°F

Sunshine & warmth in April

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 Cayman Islands in April. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early April
1st–15th		 100% n=120
Late April
16th–end		 100% n=120
Full month average 100% n=240
12.2 h median sunshine per day 100% of days exceed 8 h sunshine 58% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 10%. Sunshine-based “warm & sunny”: 100%. The 90-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

Cayman Islands is a poor choice for sun in April: just 10% of days clear historically (n=240). January is the historically strongest month for sun here. The 8-year record is consistent — this is not a fluke bad stretch.

→ See all destinations in January — historically the best month for sun in Cayman Islands.

Every month in Cayman Islands

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

Historical clear-sky % for Cayman Islands, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 19% n=248 All destinations →
February 11% n=226 All destinations →
March 17% n=248 All destinations →
April ← this page 10% n=240 All destinations →
May 5% n=248 All destinations →
June 4% n=240 All destinations →
July 2% n=248 All destinations →
August 4% n=248 All destinations →
September 4% n=240 All destinations →
October 5% n=248 All destinations →
November 12% n=240 All destinations →
December 12% n=248 All destinations →

Frequently asked

Does it rain in Cayman Islands in April?

Yes, frequently. In Cayman Islands, 58% of days in April see measurable rain, based on 8 years of ERA5 historical data (n=240 days, 2018–2025). This is a historical average, not a forecast.

Is Cayman Islands good for sun in April?

Not usually. Cayman Islands is historically overcast in April: only 10% of days are clear (avg high 84°F, n=240 days, ERA5 2018–2025). January is historically far better for sun here.

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.