Gabon weather by month

In Libreville, the average share of the sky covered by clouds shows moderate seasonal variation over the course of the year.

The clearer part of the year begins around May 30 and lasts for 3.4 months, ending around September 8. The clearest month is July, when the sky is clear, mostly clear, or partly cloudy 20% of the time on average.

The cloudier part of the year begins around September 9 and lasts for 3.0 months, ending around December 9. The cloudiest month is November, when it is overcast or mostly cloudy 93% of the time.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Across the year, average wind speed in Libreville is typically calm, near 9 km/h, and varies moderately with the seasons.

The windier part of the year lasts 4.7 months, from around May 25 to Oct 14. The windiest month is August, averaging about 13 km/h (light breeze).

The calmer part of the year runs from around Oct 15 to May 24, with April the calmest month at about 7 km/h.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Libreville receives about 4.5 kWh/m² a day of solar energy — bright — and it stays remarkably steady, holding between 4.0 and 5.0 kWh/m² all year. For solar panels, output here is a flat line, not a seasonal wave.