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SunnyDays

ERA5 almanac — 8 years of real data

Puerto Vallarta in December

Puerto Vallarta in December: 5% of days see measurable rain, 81°F average high, 85% of days historically clear (n=248, ERA5 2018–2025).

Historically one of the better months to visit Puerto Vallarta for sun: 85% of days are clear on average (n=248, avg high 81°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 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 December

Clear-sky percentage for Puerto Vallarta in December, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early December
1st–15th		 85% n=120 81°F
Late December
16th–end		 85% n=128 81°F
Full month average 85% n=248 81°F

Sunshine & warmth in December

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 December. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early December
1st–15th		 98% n=120
Late December
16th–end		 95% n=128
Full month average 96% n=248
10.0 h median sunshine per day 91% of days exceed 8 h sunshine 5% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 85%. Sunshine-based “warm & sunny”: 96%. The 11-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 one of the best destinations for sun in December: 85% of days meet the clear bar (avg high 81°F, n=248 days across 8 years). Pack for outdoor activity — this month consistently delivers.

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 1% n=248 All destinations →
September 4% n=240 All destinations →
October 22% n=248 All destinations →
November 77% n=240 All destinations →
December ← this page 85% n=248 All destinations →

Frequently asked

Does it rain in Puerto Vallarta in December?

Rarely. Only 5% of days in Puerto Vallarta see measurable rain in December, 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 December?

Yes. Puerto Vallarta is historically strong for sun in December: 85% of days are clear on average (avg high 81°F, n=248 days, ERA5 2018–2025).

How Puerto Vallarta compares in December

Head-to-head clear-sky comparisons against destinations travelers plausibly weigh against Puerto Vallarta 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.