ERA5 almanac comparison — 8 years of real data
Charleston vs Houston: weather in January
Essentially a tie in January: Charleston is 1% clear historically, Houston is 2% clear (8-year ERA5 average) — within the noise. Avg high 57°F vs 62°F. Pick based on flight time or price, not weather — the weather won't decide this one for you.
Charleston
SC
- Clear days, January
- 1%
- Sample size
- n=248 days
- Avg high
- 57°F
- Early January (1st–15th)
- 2%
- Late January (16th–end)
- 0%
- Rain frequency
- 31% of days
Houston
TX
- Clear days, January
- 2%
- Sample size
- n=248 days
- Avg high
- 62°F
- Early January (1st–15th)
- 4%
- Late January (16th–end)
- 0%
- Rain frequency
- 38% of days
Frequently asked
Is Charleston or Houston warmer in January?
Houston runs warmer by day in January. Charleston averages highs of 57°F (highs n=248 days); Houston averages highs of 62°F (highs n=248 days) (ERA5 2018–2025). Historical averages, not a forecast.
Does it rain more in Charleston or Houston in January?
Days with measurable rain: Charleston 31%, Houston 38% (n=248 and n=248 days). ERA5 2018–2025; historical, not a forecast.
Which is sunnier in January, Charleston or Houston?
Essentially a tie in January: Charleston is 1% clear historically, Houston is 2% clear (8-year ERA5 average) — within the noise. Avg high 57°F vs 62°F. Pick based on flight time or price, not weather — the weather won't decide this one for you.
Compare Charleston vs Houston 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.