ERA5 almanac comparison — 8 years of real data
Houston vs San Diego: weather in August
San Diego is the clear winner for sun in August: 90% of days historically clear versus just 23% in Houston — a 67-point gap across 8 years of ERA5 data. Houston also sees measurably more rain than San Diego this month (55% vs 2% of days). This isn't close.
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.
Houston
TX
- Clear days, August
- 23%
- Sample size
- n=248 days
- Avg high
- 92°F
- Early August (1st–15th)
- 22%
- Late August (16th–end)
- 23%
- Rain frequency
- 55% of days
San Diego
CA
- Clear days, August
- 90%
- Sample size
- n=248 days
- Avg high
- 78°F
- Early August (1st–15th)
- 92%
- Late August (16th–end)
- 88%
- Rain frequency
- 2% of days
Compare Houston vs San Diego 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.