ERA5 almanac comparison — 8 years of real data
Coeur d'Alene vs Napa: weather in August
Napa edges out Coeur d'Alene for sun in August: 96% clear historically versus 75% (8-year ERA5 average, a 21-point gap). Both are viable — Napa is the safer bet.
What you are reading: 8-year historical averages, not a forecast.
Either destination can still surprise you this specific August. For this
week’s actual forecast, each destination links to its live page below.
Coeur d'Alene
ID
- Clear days, August
- 75%
- Sample size
- n=248 days
- Avg high
- 85°F
- Early August (1st–15th)
- 82%
- Late August (16th–end)
- 69%
Napa
CA
- Clear days, August
- 96%
- Sample size
- n=248 days
- Avg high
- 88°F
- Early August (1st–15th)
- 97%
- Late August (16th–end)
- 95%
- Rain frequency
- 1% of days
Compare Coeur d'Alene vs Napa 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 7-day outlook for any destination is on its own page and may differ from the long-run average. Data from Open-Meteo.