ERA5 almanac comparison — 8 years of real data
Phoenix vs Tulum: weather in May
Phoenix is the clear winner for sun in May: 95% of days historically clear versus just 16% in Tulum — a 79-point gap across 8 years of ERA5 data. Tulum also sees measurably more rain than Phoenix this month (51% vs 2% of days). This isn't close.
Phoenix
AZ
- Clear days, May
- 95%
- Sample size
- n=248 days
- Avg high
- 96°F
- Early May (1st–15th)
- 92%
- Late May (16th–end)
- 97%
- Rain frequency
- 2% of days
Tulum
Mexico
- Clear days, May
- 16%
- Sample size
- n=248 days
- Avg high
- 87°F
- Early May (1st–15th)
- 24%
- Late May (16th–end)
- 9%
- Rain frequency
- 51% of days
Frequently asked
Is Phoenix or Tulum warmer in May?
Phoenix runs warmer by day in May. Phoenix averages highs of 96°F (highs n=248 days); Tulum averages highs of 87°F (highs n=248 days) (ERA5 2018–2025). Historical averages, not a forecast.
Does it rain more in Phoenix or Tulum in May?
Tulum is measurably wetter than Phoenix. Days with measurable rain: Phoenix 2%, Tulum 51% (n=248 and n=248 days). ERA5 2018–2025; historical, not a forecast.
Which is sunnier in May, Phoenix or Tulum?
Phoenix is the clear winner for sun in May: 95% of days historically clear versus just 16% in Tulum — a 79-point gap across 8 years of ERA5 data. Tulum also sees measurably more rain than Phoenix this month (51% vs 2% of days). This isn't close.
Compare Phoenix vs Tulum 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.