San Francisco Weather in May
United States · Mediterranean climate · Data averaged from 2020-01-01 to 2024-12-31 (5 years)
May in San Francisco sees average temperatures ranging from a low of 11.2°C (52.2°F) to a high of 17.3°C (63.1°F), with a mean of 13.9°C (57.0°F). Compared to the annual average of 13.5°C (56.3°F), this month is 0.4°C warmer than the yearly norm. Precipitation averages 16.5mm, making it approximately 32.0mm drier than the monthly average of 49.0mm. The city receives an average of 12.8 hours of sunshine per day during May, with relative humidity averaging 76.2%. Wind speeds reach an average maximum of 31.9 km/h. For travelers, this month offers a temperature experience in San Francisco, with drier-than-average conditions compared to the rest of the year.
If you're planning outdoor activities in San Francisco, ignore the season — focus on the hour. I hiked Lands End in July at 2pm in a t-shirt and was shivering by 4pm when the fog rolled in. The 5°C temperature swing between coast and bay is real. Best running conditions: September-October, when the marine layer retreats and 22°C hits the city. Pack a windbreaker for any coastal trail, year-round. Marin Headlands is magnificent but windy; aim for 10am-2pm. February-March brings surprisingly green hills and empty trails — my favorite hiking window.
May vs Adjacent Months
| Metric | April | May | June |
|---|---|---|---|
| Mean Temp | 12.1°C (53.8°F) | 13.9°C (57.0°F) | 15.2°C (59.4°F) |
| Rainfall | 23.0mm | 16.5mm | 2.0mm |
| Sunshine | 11.7 hrs | 12.8 hrs | 13.1 hrs |
| Humidity | 78.4% | 76.2% | 77.1% |
| Wind | 30.4 km/h | 31.9 km/h | 32.9 km/h |
| Rainy Days | 4.4 | 4.2 | 1.4 |
Seasonal Context
May falls in Spring in the Northern Hemisphere. Spring is a transitional season with temperatures rising from winter lows. For travelers visiting San Francisco 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 San Francisco in May?
The average temperature in San Francisco during May ranges from 11.2°C (52.2°F) to 17.3°C (63.1°F), with a mean of 13.9°C (57.0°F).
How much does it rain in San Francisco in May?
San Francisco receives an average of 16.5mm of precipitation in May, spread across approximately 4.2 rainy days.
What should I pack for San Francisco in May?
Based on May weather data, pack warm layers, a medium jacket, and waterproof outerwear.
Is May a good time to visit San Francisco?
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 San Francisco
Cities with Similar May Climate (Mediterranean)
Data Source: Open-Meteo historical archive (2020-01-01 to 2024-12-31). Daily measurements aggregated into monthly climate normals. Coordinates: 37.77°, -122.42°. Timezone: America/Los_Angeles. Last updated: 2026-07-30.