May Weather in San Rafael, United States

Last updated: June 24, 2025

In May, the average temperature in San Rafael, United States hovers around 15°C (60°F), with a minimum of 7°C (45°F) and a peak reaching 30°C (86°F). Expect about 20 mm (0.8 in) of precipitation over 2 days, while the air carries an average humidity level of 83%. Stay prepared for a mix of warm days and refreshing showers!

May Temperature in San Rafael

In May in San Rafael, the average temperature is 15°C (60°F). Maximum temperatures can reach 30°C (86°F), while minimums can drop as low as 7°C (45°F). This makes San Rafael an ideal destination for travelers seeking mild weather and pleasant experiences during this time of year.

May Weather in San Rafael: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in San Rafael, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In San Rafael, May typically has an average temperature of 15°C (60°F), with highs reaching up to 30°C (86°F) and lows dropping to around 7°C (45°F).
JanFebMarAprMayJunJulAugSepOctNovDec515253575963636465625551
Data source: Temperature data for San Rafael generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in San Rafael

In San Rafael in May, the precipitation amount is 20 mm (0.8 in) over the course of 2 days.

May Precipitation Trends in San Rafael

The chart displays monthly precipitation patterns in San Rafael, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In San Rafael, May typically receives around 20 mm (0.8 inches) of precipitation spread over approximately 2 days.
JanFebMarAprMayJunJulAugSepOctNovDec1111168035202212304898
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in San Rafael

In San Rafael in May humidity is 83%. With an average temperature of 15°C (60°F), this humidity feels like a damp blanket wrapping around you, making travel a bit uncomfortable and sticky, as the air clings to your skin and dampens your clothes.

May Average Humidity in San Rafael

This chart illustrates the average monthly humidity levels in San Rafael, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in San Rafael is approximately 83%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec85%82%82%79%83%84%87%87%86%80%79%79%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in San Rafael

In San Rafael in May, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in San Rafael.

Maximum UV Index Levels in San Rafael for May

The chart shows the monthly maximum UV Index (UVI) for San Rafael in May, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In May, the maximum UV index in San Rafael typically reaches 10, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec3589101111109643
Data source: San Rafael May UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

How May Weather in San Rafael Compares to Other Months

Weather in San Rafael varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in San Rafael, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in San Rafael, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather10°C (51°F)111 mm (4.4 inches)85%moderate
February Weather11°C (52°F)116 mm (4.6 inches)82%moderate
March Weather12°C (54°F)80 mm (3.1 inches)82%very high
April Weather14°C (57°F)35 mm (1.4 inches)79%very high
May Weather15°C (60°F)20 mm (0.8 inches)83%very high
June Weather17°C (63°F)2 mm (0.1 inches)84%extreme
July Weather17°C (63°F)2 mm (0.1 inches)87%extreme
August Weather18°C (64°F)1 mm (0.1 inches)87%very high
September Weather18°C (65°F)2 mm (0.1 inches)86%very high
October Weather16°C (62°F)30 mm (1.2 inches)80%high
November Weather13°C (55°F)48 mm (1.9 inches)79%moderate
December Weather10°C (51°F)98 mm (3.9 inches)79%moderate

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