Climate Insights for Portland Airport

The climate in Portland Airport is temperate. The average annual temperature is 14°C and approximately 726mm of precipitation falls per year. July is the wettest month, receiving around 106mm of rainfall. Portland Airport is in the Southern Hemisphere. The seasons are reversed — summer runs from December to February, while winter falls between June and August. The summer months are: January, February, March. The coldest months are July, August, June, when temperatures can drop to 9°C.

Portland Airport sees moderate temperature variation throughout the year, ranging from 9°C to 21°C. January is the warmest month, though highs remain moderate at 21°C with a mean of 18°C. July is the coolest month, with minimum temperatures around 9°C and an average of 11°C. Daily temperature variation is modest, with an average difference of 4°C between highs and lows.

Portland Airport is a relatively dry area, receiving approximately 726mm of precipitation annually, which averages out to around 61mm per month. The wettest month is July, averaging 106mm of rainfall. August and June also tend to see above-average precipitation. The driest month is February, with just 23mm. That's 83mm less than July, the wettest month. Precipitation varies noticeably between seasons, with the second half (July to December) of the year generally seeing more rainfall.

Portland Airport is moderately windy, with an average annual wind speed of 28km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is July, averaging 31km/h, which can feel quite blustery and may affect outdoor activities. The calmest conditions occur in April, with average winds dropping to 25km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 6km/h between the calmest and windiest months. Wind tends to be stronger during winter months, driven by seasonal pressure systems. The seasonal averages break down to 29km/h in winter, 28km/h in spring, 26km/h in summer, 26km/h in autumn.

It is currently autumn in Portland Airport, which began on March 20, 2026. Portland Airport is in the Southern Hemisphere, where the seasons are reversed — spring starts in September, summer in December, autumn in March, and winter in June. The warmest period peaks in January at around 21°C, while the coldest stretch bottoms out in July near 9°C. Winter is next, beginning on June 21, 2026 — 88 days from now.

The best time to visit Portland Airport is during January, February, March and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 17°C with modest rainfall averaging 32mm per month. By contrast, July can be quite cold with temperatures dropping to 9°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.

The table below shows monthly climate averages for Portland Airport based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.