ERA5 almanac comparison — 8 years of real data
Las Vegas vs San Antonio: weather in March
Essentially a tie in March: Las Vegas is 32% clear historically, San Antonio is 33% clear (8-year ERA5 average) — within the noise. Avg high 70°F vs 78°F. San Antonio also sees measurably more rain than Las Vegas this month (32% vs 12% of days). Pick based on flight time or price, not weather — the weather won't decide this one for you.
Las Vegas
NV
- Clear days, March
- 32%
- Sample size
- n=248 days
- Avg high
- 70°F
- Early March (1st–15th)
- 18%
- Late March (16th–end)
- 45%
- Rain frequency
- 12% of days
San Antonio
TX
- Clear days, March
- 33%
- Sample size
- n=248 days
- Avg high
- 78°F
- Early March (1st–15th)
- 32%
- Late March (16th–end)
- 33%
- Rain frequency
- 32% of days
Compare Las Vegas vs San Antonio 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.