Papua New Guinea weather by month

In Port Moresby, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.

The clearer part of the year begins around May 10 and lasts for 6.7 months, ending around November 30. The clearest month is August, when the sky is clear, mostly clear, or partly cloudy 39% of the time on average.

The cloudier part of the year begins around December 1 and lasts for 5.3 months, ending around May 9. The cloudiest month is March, 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 Port Moresby is typically calm, near 12 km/h, and varies moderately with the seasons.

The windier part of the year lasts 5.5 months, from around May 12 to Oct 24. The windiest month is July, averaging about 17 km/h (light breeze).

The calmer part of the year runs from around Oct 25 to May 11, with December the calmest month at about 8 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.

Port Moresby receives about 5.1 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 4.2 and 6.0 kWh/m².

The brighter stretch of the year lasts 5.9 months, from around Aug 29 to Feb 24. The brightest month is October, averaging about 5.9 kWh/m² (bright).

The dimmest month is June, down near 4.3 kWh/m² — roughly 27% less than the October peak.