The highest day temperature in May 2025 was 80°F. The lowest night temperature was 38°F. The average values for day and night temperatures during May were 65.8°F и 51.8°F respectivly.

Most of the days in May are sunny but you can also expect cloudy and gloomy days.

Precipitation total in May for San Rafael is 0.1 in. It makes may one of the least rainy months of the year.

The average wind speed in May is 6.5 mph. It makes May one of the most windless months of the year for San Rafael.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for San Rafael in May is 8.4 hours.