May weather forecastMillbrae, CA
May
Weather in May
May, the last month of the spring in Millbrae, is also an enjoyable month, with an average temperature varying between 50.5°F (10.3°C) and 63.1°F (17.3°C).Temperature
The advent of May signifies a minor shift to an average high-temperature of a still enjoyable 63.1°F (17.3°C), aligning closely with April. Millbrae usually reports an average low-temperature of 50.5°F (10.3°C) during the month of May.Humidity
In May, the average relative humidity is 76%.Rainfall
In Millbrae, in May, during 5.7 rainfall days, 0.63" (16mm) of precipitation is typically accumulated. Throughout the year, there are 81.5 rainfall days, and 12.8" (325mm) of precipitation is accumulated.Daylight
The average length of the day in May is 14h and 13min.On the first day of May, sunrise is at 6:12 am and sunset at 8:00 pm. On the last day of the month, sunrise is at 5:49 am and sunset at 8:25 pm PDT.
Sunshine
The average sunshine in May is 10.5h.UV index
In Millbrae, California, the average daily maximum UV index in May is 4. A UV Index reading of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for average individuals.Note: The daily maximum UV index of 4 in May interprets into the following advice:
Adopt protective measures - Suggestions to resist sunburn are offered. Avoiding direct sun during mid-day hours can prevent harmful UV radiation exposure. Employ a wide-brim hat for potent defense against up to 50% of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Millbrae, CA
- Average high temperature in May: 63.1°F
The warmest month (with the highest average high temperature) is September (70.2°F).
The month with the lowest average high temperature is December (55.6°F).
- Average low temperature in May: 50.5°F
The month with the highest average low temperature is September (56.8°F).
The coldest month (with the lowest average low temperature) is January (47.5°F).
Average pressure in May
Millbrae, CA
- Average pressure in May: 29.98"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is September (29.92"Hg).
Average wind speed in May
Millbrae, CA
- Average wind speed in May: 8.2mph
The windiest month (with the highest average wind speed) is April (8.3mph).
The calmest month (with the lowest average wind speed) is September (6.1mph).
Average humidity in May
Millbrae, CA
- Average humidity in May: 76%
The month with the highest relative humidity is August (78%).
The month with the lowest relative humidity is October (70%).
Average rainfall in May
Millbrae, CA
- Average rainfall in May: 0.63"
The wettest month (with the highest rainfall) is February (2.44").
The driest month (with the least rainfall) is July (0.08").
Average rainfall days in May
Millbrae, CA
- Average rainfall days in May: 5.7 days
The month with the highest number of rainy days is March (12.8 days).
The months with the least rainy days are June and July (2.4 days).
Average daylight in May /
Average sunshine in May
Millbrae, CA
- Average daylight in May: 14h and 12min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in May: 10h and 30min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is December (Average sunshine: 5h and 48min).
Average sunshine days in May
Millbrae, CA
- Average sunshine days in May: 22.1 days
The month with the most sunshine days is July (24.6 days).
The month with the least sunshine days is March (16.3 days).
Average UV index in May
Millbrae, CA
- Average UV index in May: 4
The months with the highest UV index are June, July, August and September (UV index 5).
The months with the lowest UV index are February and December (UV index 3).
Average cloud cover in May
Millbrae, CA
- Average cloud cover in May: 27
The month with the most cloud cover is March (Cloud cover 36).
The months with the least cloud cover are July and September (Cloud cover 15).
Average visibility in May
Millbrae, CA
- Average visibility in May: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





