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SunnyDays

ERA5 almanac — 8 years of real data

Phuket in December

Phuket in December: 55% of days see measurable rain, 85°F average high, 16% of days historically clear (n=248, ERA5 2018–2025).

Phuket in December is historically a poor month for sun: only 16% of days clear across 8 years (n=248, avg high 85°F). February is the clearest month for Phuket 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 Phuket 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 Phuket 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		 9% n=120 85°F
Late December
16th–end		 22% n=128 85°F
Full month average 16% n=248 85°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 Phuket 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		 88% n=120
Late December
16th–end		 95% n=128
Full month average 92% n=248
10.8 h median sunshine per day 85% of days exceed 8 h sunshine 55% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 16%. Sunshine-based “warm & sunny”: 92%. The 76-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

Phuket is a poor choice for sun in December: just 16% of days clear historically (n=248). February 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 February — historically the best month for sun in Phuket.

Every month in Phuket

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

Historical clear-sky % for Phuket, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 25% n=248 All destinations →
February 41% n=226 All destinations →
March 29% n=248 All destinations →
April 8% n=240 All destinations →
May 5% n=248 All destinations →
June 8% n=240 All destinations →
July 8% n=248 All destinations →
August 6% n=248 All destinations →
September 3% n=240 All destinations →
October 2% n=248 All destinations →
November 4% n=240 All destinations →
December ← this page 16% n=248 All destinations →

Frequently asked

Does it rain in Phuket in December?

Yes, frequently. In Phuket, 55% of days in December 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 Phuket good for sun in December?

Not usually. Phuket is historically overcast in December: only 16% of days are clear (avg high 85°F, n=248 days, ERA5 2018–2025). February is historically far better for sun here.

How Phuket compares in December

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