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SunnyDays

ERA5 almanac — 8 years of real data

Puerto Vallarta in August

Puerto Vallarta in August: 85% of days see measurable rain, 87°F average high, 1% of days historically clear (n=248, ERA5 2018–2025).

Puerto Vallarta in August is historically a poor month for sun: only 1% of days clear across 8 years (n=248, avg high 87°F). March is the clearest month for Puerto Vallarta 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 Puerto Vallarta 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 August

Clear-sky percentage for Puerto Vallarta in August, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early August
1st–15th		 3% n=120 87°F
Late August
16th–end		 0% n=128 87°F
Full month average 1% n=248 87°F

Sunshine & warmth in August

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 Puerto Vallarta in August. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early August
1st–15th		 91% n=120
Late August
16th–end		 88% n=128
Full month average 89% n=248
8.9 h median sunshine per day 71% of days exceed 8 h sunshine 85% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 1%. Sunshine-based “warm & sunny”: 89%. The 88-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

Puerto Vallarta is historically almost never clear in August: only 1% of days meet the clear bar across 8 years (n=248). Come back in March if you want clear skies here. Plan entirely around indoor or overcast-friendly activities.

→ See all destinations in March — historically the best month for sun in Puerto Vallarta.

Every month in Puerto Vallarta

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

Historical clear-sky % for Puerto Vallarta, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 86% n=248 All destinations →
February 87% n=226 All destinations →
March 99% n=248 All destinations →
April 99% n=240 All destinations →
May 93% n=248 All destinations →
June 38% n=240 All destinations →
July 10% n=248 All destinations →
August ← this page 1% n=248 All destinations →
September 4% n=240 All destinations →
October 22% n=248 All destinations →
November 77% n=240 All destinations →
December 85% n=248 All destinations →

Frequently asked

Does it rain in Puerto Vallarta in August?

Yes, frequently. In Puerto Vallarta, 85% of days in August 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 Puerto Vallarta good for sun in August?

Not usually. Puerto Vallarta is historically overcast in August: only 1% 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.