Climate averages 1991–2020
Port Moresby weather
in December.
A hot, wet month: the 3rd warmest and the 8th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a hot month in Port Moresby: daytime highs average 30.6°C and nights cool to about 23.7°C. By daytime temperature it is the 3rd warmest of the 12 months.
Expect about 170 mm of rain on roughly 21 days, which makes December a wet month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 40 min on an average December day.
The nearest other city in this atlas is Merauke (749 km away). In December its highs average 30.2°C, about as warm as Port Moresby, with 208 mm of rain.
From December to January, average highs fall by 0.5°C to 30.1°C, and monthly rainfall rises from 170 mm to 230 mm.
The annual picture
December in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Port Moresby climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 30.1°C23.6°C | 23.6°C | 230 | 22.9 | 12.613 h |
| February | 29.9°C23.6°C | 23.6°C | 197 | 21.1 | 12.412 h |
| March | 29.3°C23.2°C | 23.2°C | 276 | 24.9 | 12.212 h |
| April | 29.3°C23.3°C | 23.3°C | 177 | 20.2 | 11.912 h |
| May | 29.2°C23.3°C | 23.3°C | 81 | 12.2 | 11.712 h |
| June | 28.9°C23.1°C | 23.1°C | 51 | 8.6 | 11.612 h |
| July | 28.6°C22.6°C | 22.6°C | 29 | 5.2 | 11.612 h |
| August | 29.2°C22.4°C | 22.4°C | 34 | 6.4 | 11.812 h |
| September | 30.1°C22.8°C | 22.8°C | 45 | 7.8 | 12.012 h |
| October | 30.8°C23.2°C | 23.2°C | 62 | 11.0 | 12.312 h |
| November | 31.0°C23.5°C | 23.5°C | 110 | 15.5 | 12.513 h |
| December, selected | 30.6°C23.7°C | 23.7°C | 170 | 21.2 | 12.713 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
December in nearby cities
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Port Moresby) is explained once on the Port Moresby year overview and on the Sources, method and limits page.