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SunnyDays

ERA5 almanac — 8 years of real data

Huatulco in July

Huatulco in July: 70% of days see measurable rain, 87°F average high, 12% of days historically clear (n=248, ERA5 2018–2025).

Huatulco in July is historically a poor month for sun: only 12% of days clear across 8 years (n=248, avg high 87°F). March is the clearest month for Huatulco 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 Huatulco 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 July

Clear-sky percentage for Huatulco in July, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early July
1st–15th		 12% n=120 87°F
Late July
16th–end		 12% n=128 87°F
Full month average 12% n=248 87°F

Sunshine & warmth in July

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 Huatulco in July. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early July
1st–15th		 95% n=120
Late July
16th–end		 98% n=128
Full month average 97% n=248
11.6 h median sunshine per day 92% of days exceed 8 h sunshine 70% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 12%. Sunshine-based “warm & sunny”: 97%. The 85-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

Huatulco is a poor choice for sun in July: just 12% of days clear historically (n=248). March 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 March — historically the best month for sun in Huatulco.

Every month in Huatulco

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

Historical clear-sky % for Huatulco, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 69% n=248 All destinations →
February 68% n=226 All destinations →
March 75% n=248 All destinations →
April 67% n=240 All destinations →
May 40% n=248 All destinations →
June 7% n=240 All destinations →
July ← this page 12% n=248 All destinations →
August 5% n=248 All destinations →
September 4% n=240 All destinations →
October 9% n=248 All destinations →
November 36% n=240 All destinations →
December 68% n=248 All destinations →

Frequently asked

Does it rain in Huatulco in July?

Yes, frequently. In Huatulco, 70% of days in July see measurable rain, based on 8 years of ERA5 historical data (n=248 days, 2018–2025). This is a historical average, not a forecast.

Is Huatulco good for sun in July?

Not usually. Huatulco is historically overcast in July: only 12% of days are clear (avg high 87°F, n=248 days, ERA5 2018–2025). March 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.