Climate Insights for Sedro-Woolley

The climate in Sedro-Woolley is cool. The average annual temperature is 10°C and approximately 1916mm of precipitation falls per year. November is the wettest month, receiving around 287mm of rainfall. Sedro-Woolley is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: August, July, September. The coldest months are February, December, January, when temperatures can drop to 1°C. Sedro-Woolley experiences heavy snowfall, typically from January through December.

Temperatures in Sedro-Woolley vary considerably across the year, with a 22°C difference between the coldest and warmest months. August is the warmest month, though highs remain moderate at 23°C with a mean of 18°C. February is the coolest month, with minimum temperatures around 1°C and an average of 3°C. Daily temperature variation is modest, with an average difference of 7°C between highs and lows. The sharpest temperature change occurs between September and October, with a 5°C shift in average temperatures.

Sedro-Woolley is a fairly wet location, receiving approximately 1916mm of precipitation annually, which averages out to around 160mm per month. The wettest month is November, averaging 287mm of rainfall. December and January also tend to see above-average precipitation. The driest month is July, with just 24mm. That's 262mm less than November, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic. Sedro-Woolley receives heavy snowfall, accumulating around 244cm annually from January through December. The snowiest month is February, with approximately 65cm. Winter travel should account for significant snow cover.

Sedro-Woolley is relatively calm, with an average annual wind speed of 7km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is January, averaging 9km/h, though still comfortable for most outdoor activities. The calmest conditions occur in August, with average winds dropping to 5km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 4km/h gap 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 8km/h in winter, 7km/h in spring, 5km/h in summer, 7km/h in autumn.

It is currently summer in Sedro-Woolley, which began on June 21, 2026. Sedro-Woolley is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in August at around 23°C, while the coldest stretch bottoms out in February near 1°C. Autumn is next, beginning on September 23, 2026 (7 days from now).

The best time to visit Sedro-Woolley is during July and August, when the weather is most comfortable for travellers. During these months, average temperatures hover around 18°C with modest rainfall averaging 30mm per month. By contrast, February can be quite cold with temperatures dropping to 1°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 Sedro-Woolley 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. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. 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.