ERA5 almanac comparison — 8 years of real data
Cayman Islands vs Phoenix: weather in January
Essentially a tie in January: Cayman Islands is 19% clear historically, Phoenix is 17% clear (8-year ERA5 average) — within the noise. Avg high 81°F vs 66°F. Cayman Islands also sees measurably more rain than Phoenix this month (45% vs 12% of days). Pick based on flight time or price, not weather — the weather won't decide this one for you.
Cayman Islands
Cayman Islands
- Clear days, January
- 19%
- Sample size
- n=248 days
- Avg high
- 81°F
- Early January (1st–15th)
- 17%
- Late January (16th–end)
- 21%
- Rain frequency
- 45% of days
Phoenix
AZ
- Clear days, January
- 17%
- Sample size
- n=248 days
- Avg high
- 66°F
- Early January (1st–15th)
- 13%
- Late January (16th–end)
- 20%
- Rain frequency
- 12% of days
Frequently asked
Is Cayman Islands or Phoenix warmer in January?
Cayman Islands runs warmer by day in January. Cayman Islands averages highs of 81°F (highs n=248 days); Phoenix averages highs of 66°F (highs n=248 days) (ERA5 2018–2025). Historical averages, not a forecast.
Does it rain more in Cayman Islands or Phoenix in January?
Cayman Islands is measurably wetter than Phoenix. Days with measurable rain: Cayman Islands 45%, Phoenix 12% (n=248 and n=248 days). ERA5 2018–2025; historical, not a forecast.
Which is sunnier in January, Cayman Islands or Phoenix?
Essentially a tie in January: Cayman Islands is 19% clear historically, Phoenix is 17% clear (8-year ERA5 average) — within the noise. Avg high 81°F vs 66°F. Cayman Islands also sees measurably more rain than Phoenix this month (45% vs 12% of days). Pick based on flight time or price, not weather — the weather won't decide this one for you.
Compare Cayman Islands vs Phoenix in another month
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 forecast for any destination is on its own page and may differ from the long-run average. Data from Open-Meteo.