Climate Insights for Portland

The climate in Portland is temperate. The average annual temperature is 13°C and approximately 683mm of precipitation falls per year. March is the wettest month, receiving around 88mm of rainfall. Portland 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, December, February. The coldest months are July, August, June, when temperatures can drop to 2°C.

Temperatures in Portland vary considerably across the year, with a 24°C difference between the coldest and warmest months. The warmest month is January, when average highs reach 26°C and the mean temperature sits around 20°C. July is the coolest month, with minimum temperatures around 2°C and an average of 6°C. On average, daily temperatures fluctuate by about 11°C between overnight lows and afternoon highs. The sharpest temperature change occurs between April and May, with a 4°C shift in average temperatures.

Portland is a relatively dry area, receiving approximately 683mm of precipitation annually, which averages out to around 57mm per month. The wettest month is March, averaging 88mm of rainfall. November and January also tend to see above-average precipitation. The driest month is May, with just 29mm. That's 59mm less than March, the wettest month. Precipitation varies noticeably between seasons, with the first half (January to June) of the year generally seeing more rainfall.

Portland is mildly breezy, with an average annual wind speed of 18km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is November, averaging 19km/h, though still comfortable for most outdoor activities. The calmest conditions occur in April, with average winds dropping to 16km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 3km/h between the calmest and windiest months.

It is currently autumn in Portland, which began on March 20, 2026. Portland 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 26°C, while the coldest stretch bottoms out in July near 2°C. Winter is next, beginning on June 21, 2026 — 88 days from now.

The best time to visit Portland is during January, February, March, November and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 18°C with modest rainfall averaging 72mm per month. By contrast, July can be quite cold with temperatures dropping to 2°C. Despite being the best months overall, some rain is still likely — pack a waterproof layer and plan a mix of indoor and outdoor activities.

The table below shows monthly climate averages for Portland 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.