ERA5 almanac — 8 years of real data

Costa Rica — Guanacaste in February

Costa Rica — Guanacaste in February: 3% of days see measurable rain, 93°F average high, 84% of days historically clear (n=226, ERA5 2018–2025).

Historically one of the better months to visit Costa Rica — Guanacaste for sun: 84% of days are clear on average (n=226, avg high 93°F). Every percentage here is a historical average from 8 years of ERA5 data — 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 — Guanacaste 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 February

Clear-sky percentage for Costa Rica — Guanacaste in February, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period	% Clear days	Sample (n)	Avg high
Early February 1st–15th	84%	n=120	93°F
Late February 16th–end	84%	n=106	93°F
Full month average	84%	n=226	93°F

Sunshine & warmth in February

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 — Guanacaste in February. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period	Warm & sunny (≥72°F, >6 h sun)	Sample (n)
Early February 1st–15th	100%	n=120
Late February 16th–end	100%	n=106
Full month average	100%	n=226

11.6 h median sunshine per day 99% of days exceed 8 h sunshine 3% of days see ≥ 1 mm rain — rain is not hidden

Comparison (old vs new): WMO-code “clear” bar: 84%. Sunshine-based “warm & sunny”: 100%. The 16-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 — Guanacaste is historically one of the best destinations for sun in February: 84% of days meet the clear bar (avg high 93°F, n=226 days across 8 years). Pack for outdoor activity — this month consistently delivers.

Every month in Costa Rica — Guanacaste

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

Historical clear-sky % for Costa Rica — Guanacaste, all months, ERA5 2018–2025.
Month	% Clear	Sample (n)
January	79%	n=248	All destinations →
February ← this page	84%	n=226	All destinations →
March	70%	n=248	All destinations →
April	33%	n=240	All destinations →
May	9%	n=248	All destinations →
June	5%	n=240	All destinations →
July	16%	n=248	All destinations →
August	6%	n=248	All destinations →
September	2%	n=240	All destinations →
October	2%	n=248	All destinations →
November	18%	n=240	All destinations →
December	62%	n=248	All destinations →

Frequently asked

Does it rain in Costa Rica — Guanacaste in February?

Rarely. Only 3% of days in Costa Rica — Guanacaste see measurable rain in February, based on 8 years of ERA5 historical data (n=226 days, 2018–2025). This is a historical average, not a forecast.

Is Costa Rica — Guanacaste good for sun in February?

Yes. Costa Rica — Guanacaste is historically strong for sun in February: 84% of days are clear on average (avg high 93°F, n=226 days, ERA5 2018–2025).

How Costa Rica — Guanacaste compares in February

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

→ Costa Rica — Guanacaste vs Mazatlán in February — Mazatlán is 85% clear historically
→ Costa Rica — Guanacaste vs Puerto Vallarta in February — Puerto Vallarta is 87% clear historically
→ Costa Rica — Guanacaste vs Los Cabos in February — Los Cabos is 88% clear historically

→ Costa Rica — Guanacaste live forecast — this week’s actual 7-day weather, not historical
→ Best destinations in February — all destinations ranked by February 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.