Friday Harbor (WA) Temperature by Month

The average annual maximum temperature in Friday Harbor, Washington State, United States of America is 14°C (57°F), with daytime highs ranging from 8°C (46°F) in December to 21°C (70°F) in August. This page covers monthly averages, day-night differences, and how Friday Harbor compares to cities worldwide.

Depending on the time of the year, temperatures range from pleasant to cold in Friday Harbor. Nighttime lows follow the same pattern, ranging from 10°C (50°F) to 3°C (37°F).

The chart below illustrates the average maximum day and minimum night temperatures in Friday Harbor by month:

The coolest part of the day is typically between 4 AM and 6 AM, while 3 PM is usually the warmest, when solar heating is at its peak. August, the city's warmest month, averages 301 hours of sunshine.

The chart below shows the average temperature throughout the year:

Friday Harbor's average annual maximum temperature is 14°C (57°F). To put that in context, here's how it compares to a few well-known destinations:

Seville, Spain averages 23°C (73°F) a year, one of the warmer cities in Western Europe, with long hot summers.

Queenstown, New Zealand averages 10°C (50°F) annually, remember seasons are flipped, so its coldest months fall in June and July.

Seoul, South Korea averages 18°C (64°F) a year, with four clear seasons, cold winters, and hot humid summers.

Adelaide, Australia averages 21°C (70°F) a year, with warm summers, mild winters, and relatively low rainfall year-round.

Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.

The readings come from a range of sources, land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.

For cities and regions with significant elevation, altitude is one of the biggest factors shaping local temperatures. As a rule of thumb, temperatures fall by around 6°C for every 1,000 metres gained, so a city at 2,000 metres will typically be around 12°C cooler than a city at sea level in the same region. Higher ground also tends to see more dramatic day-to-night temperature swings, since thinner air loses heat faster after sunset.

For more on Friday Harbor's weather, including monthly rainfall, sunshine hours, and humidity, visit our Friday Harbor climate page.