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SunnyDays

ERA5 almanac — 8 years of real data

Phuket in January

Phuket in January: 33% of days see measurable rain, 87°F average high, 25% of days historically clear (n=248, ERA5 2018–2025).

Phuket in January is historically a poor month for sun: only 25% of days clear across 8 years (n=248, avg high 87°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 January

Clear-sky percentage for Phuket in January, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early January
1st–15th		 19% n=120 87°F
Late January
16th–end		 30% n=128 87°F
Full month average 25% n=248 87°F

Sunshine & warmth in January

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 January. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early January
1st–15th		 97% n=120
Late January
16th–end		 100% n=128
Full month average 99% n=248
11.0 h median sunshine per day 96% of days exceed 8 h sunshine 33% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 25%. Sunshine-based “warm & sunny”: 99%. The 74-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 mostly overcast in January historically: only 25% of days are clear across 8 years (n=248), avg high 87°F. If you want sun in Phuket, February is historically much better. Most visitors this month will see more clouds than sun.

→ 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 ← this page 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 16% n=248 All destinations →

Frequently asked

Does it rain in Phuket in January?

Sometimes. Phuket sees measurable rain on 33% of days in January historically (n=248 days, ERA5 2018–2025) — not frequent enough to plan around, but not negligible either.

Is Phuket good for sun in January?

Not usually. Phuket is historically overcast in January: only 25% of days are clear (avg high 87°F, n=248 days, ERA5 2018–2025). February is historically far better for sun here.

How Phuket compares in January

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.