ERA5 almanac comparison — 8 years of real data
Key West vs Tucson: weather in May
Tucson is the clear winner for sun in May: 94% of days historically clear versus just 33% in Key West — a 61-point gap across 8 years of ERA5 data. Key West also sees measurably more rain than Tucson this month (38% vs 2% of days). This isn't close.
Key West
FL
- Clear days, May
- 33%
- Sample size
- n=248 days
- Avg high
- 82°F
- Early May (1st–15th)
- 38%
- Late May (16th–end)
- 29%
- Rain frequency
- 38% of days
Tucson
AZ
- Clear days, May
- 94%
- Sample size
- n=248 days
- Avg high
- 92°F
- Early May (1st–15th)
- 94%
- Late May (16th–end)
- 94%
- Rain frequency
- 2% of days
Frequently asked
Is Key West or Tucson warmer in May?
Tucson runs warmer by day in May. Key West averages highs of 82°F (highs n=248 days); Tucson averages highs of 92°F (highs n=248 days) (ERA5 2018–2025). Historical averages, not a forecast.
Does it rain more in Key West or Tucson in May?
Key West is measurably wetter than Tucson. Days with measurable rain: Key West 38%, Tucson 2% (n=248 and n=248 days). ERA5 2018–2025; historical, not a forecast.
Which is sunnier in May, Key West or Tucson?
Tucson is the clear winner for sun in May: 94% of days historically clear versus just 33% in Key West — a 61-point gap across 8 years of ERA5 data. Key West also sees measurably more rain than Tucson this month (38% vs 2% of days). This isn't close.
Compare Key West vs Tucson 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.