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SunnyDays

ERA5 almanac — 8 years of real data

Costa Rica — Manuel Antonio in March

Costa Rica — Manuel Antonio in March: 21% of days see measurable rain, 88°F average high, 34% of days historically clear (n=248, ERA5 2018–2025).

Costa Rica — Manuel Antonio in March is historically a poor month for sun: only 34% of days clear across 8 years (n=248, avg high 88°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 Costa Rica — Manuel Antonio 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 March

Clear-sky percentage for Costa Rica — Manuel Antonio in March, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early March
1st–15th		 40% n=120 88°F
Late March
16th–end		 28% n=128 88°F
Full month average 34% n=248 88°F

Sunshine & warmth in March

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 Costa Rica — Manuel Antonio in March. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early March
1st–15th		 99% n=120
Late March
16th–end		 100% n=128
Full month average 100% n=248
11.6 h median sunshine per day 99% of days exceed 8 h sunshine 21% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 34%. Sunshine-based “warm & sunny”: 100%. The 66-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

Costa Rica — Manuel Antonio is mostly overcast in March historically: only 34% of days are clear across 8 years (n=248), avg high 88°F. Most visitors this month will see more clouds than sun.

Every month in Costa Rica — Manuel Antonio

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

Historical clear-sky % for Costa Rica — Manuel Antonio, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 37% n=248 All destinations →
February 51% n=226 All destinations →
March ← this page 34% n=248 All destinations →
April 8% n=240 All destinations →
May 4% n=248 All destinations →
June 2% n=240 All destinations →
July 5% n=248 All destinations →
August 3% n=248 All destinations →
September 0% n=240 All destinations →
October 0% n=248 All destinations →
November 4% n=240 All destinations →
December 22% n=248 All destinations →

Frequently asked

Does it rain in Costa Rica — Manuel Antonio in March?

Sometimes. Costa Rica — Manuel Antonio sees measurable rain on 21% of days in March historically (n=248 days, ERA5 2018–2025) — not frequent enough to plan around, but not negligible either.

Is Costa Rica — Manuel Antonio good for sun in March?

It's mixed. Costa Rica — Manuel Antonio in March is clear on 34% of days historically (avg high 88°F, n=248 days, ERA5 2018–2025) — the outcome varies year to year.

How Costa Rica — Manuel Antonio compares in March

Head-to-head clear-sky comparisons against destinations travelers plausibly weigh against Costa Rica — Manuel Antonio 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.