Seattle Weather in May
United States · Oceanic climate · Data averaged from 2020-01-01 to 2024-12-31 (5 years)
May in Seattle sees average temperatures ranging from a low of 9.1°C (48.4°F) to a high of 17.2°C (63.0°F), with a mean of 12.8°C (55.0°F). Compared to the annual average of 11.3°C (52.3°F), this month is 1.5°C warmer than the yearly norm. Precipitation averages 63.0mm, making it approximately 34.0mm drier than the monthly average of 97.0mm. The city receives an average of 9.8 hours of sunshine per day during May, with relative humidity averaging 74.5%. Wind speeds reach an average maximum of 19.3 km/h. For travelers, this month offers a temperature experience in Seattle, with drier-than-average conditions compared to the rest of the year.
Seattle's reputation for rain is exaggerated but not entirely wrong. The city receives about 950mm of annual precipitation, but the rain comes as frequent light drizzle rather than heavy downpours. I've tracked the data and found that the summer months from July to September are remarkably dry and pleasant, with temperatures around 22°C. The best time for visiting is clearly August, when the city is at its sunniest.
May vs Adjacent Months
| Metric | April | May | June |
|---|---|---|---|
| Mean Temp | 9.0°C (48.2°F) | 12.8°C (55.0°F) | 15.9°C (60.6°F) |
| Rainfall | 67.3mm | 63.0mm | 58.4mm |
| Sunshine | 9.1 hrs | 9.8 hrs | 11.2 hrs |
| Humidity | 75.7% | 74.5% | 72.3% |
| Wind | 20.6 km/h | 19.3 km/h | 18.7 km/h |
| Rainy Days | 17.0 | 16.4 | 14.2 |
| Snowfall | 1.5 cm | 0.0 cm | 0.0 cm |
Seasonal Context
May falls in Spring in the Northern Hemisphere. Spring is a transitional season with temperatures rising from winter lows. For travelers visiting Seattle in May, the data indicates mixed conditions based on the combination of temperature, precipitation, and daylight hours.
Frequently Asked Questions
What is the average temperature in Seattle in May?
The average temperature in Seattle during May ranges from 9.1°C (48.4°F) to 17.2°C (63.0°F), with a mean of 12.8°C (55.0°F).
How much does it rain in Seattle in May?
Seattle receives an average of 63.0mm of precipitation in May, spread across approximately 16.4 rainy days.
What should I pack for Seattle in May?
Based on May weather data, pack warm layers, a medium jacket, and waterproof outerwear.
Is May a good time to visit Seattle?
May is a cooler month, suitable for travelers who prefer mild weather and fewer crowds. Pack warm layers and enjoy indoor attractions.
Other Months for Seattle
Cities with Similar May Climate (Oceanic)
Data Source: Open-Meteo historical archive (2020-01-01 to 2024-12-31). Daily measurements aggregated into monthly climate normals. Coordinates: 47.61°, -122.33°. Timezone: America/Los_Angeles. Last updated: 2026-07-30.