Climate and monthly weather forecastSan Bruno, CA
Climate and monthly weather forecast
Weather in January
January, the same as December, in San Bruno, California, is another refreshing winter month, with an average temperature fluctuating between 56.3°F (13.5°C) and 47.8°F (8.8°C). As San Bruno steps into January, the average high-temperature holds at a still moderate 56.3°F (13.5°C), hinting at a minor fluctuation from the prior month. Weather in January »Weather in February
The last month of the winter, February, is also a moderate month in San Bruno, California, with an average temperature varying between 57.2°F (14°C) and 47.8°F (8.8°C). The arrival of February marks a slight shift to an average high-temperature of a still moderate 57.2°F (14°C) from January's 56.3°F (13.5°C). Weather in February »Weather in March
March, the first month of the spring in San Bruno, is also a moderate month, with an average temperature ranging between min 48°F (8.9°C) and max 58.5°F (14.7°C). The shift into March uncovers an average high-temperature of a still mild 58.5°F (14.7°C), subtly different from the previous month. Weather in March »Weather in April
April is a refreshing spring month in San Bruno, California, with an average temperature varying between 60.8°F (16°C) and 49.3°F (9.6°C). April begins with an average high-temperature of a comfortable 60.8°F (16°C), reflecting close similarity to the preceding month. Weather in April »Weather in May
May, the last month of the spring in San Bruno, is also an enjoyable month, with temperature in the range of an average low of 51.3°F (10.7°C) and an average high of 62.8°F (17.1°C). As April turns into May, the average high-temperatures rest at a still refreshing 62.8°F (17.1°C), showing a minor variation from the prior month. Weather in May »Weather in June
The first month of the summer, June, is still a comfortable month in San Bruno, California, with an average temperature fluctuating between 67.3°F (19.6°C) and 53.8°F (12.1°C). San Bruno's weather, upon June's arrival, documents an average high-temperature of a still enjoyable 67.3°F (19.6°C), nearly identical to the prior month. Weather in June »Weather in July
July is a pleasant summer month in San Bruno, California, with an average temperature fluctuating between 68.5°F (20.3°C) and 54.7°F (12.6°C). July's weather displays an average high-temperature of an agreeable 68.5°F (20.3°C), slightly varied from June's 67.3°F (19.6°C). Weather in July »Weather in August
August, the last month of the summer in San Bruno, is also an agreeable month, with temperature in the range of an average low of 56.3°F (13.5°C) and an average high of 69.1°F (20.6°C). San Bruno's August average high-temperature settles at a still agreeable 69.1°F (20.6°C), showing a near match with the preceding month. Weather in August »Weather in September
The first month of the autumn, September, is also an agreeable month in San Bruno, California, with an average temperature fluctuating between 69.8°F (21°C) and 56.5°F (13.6°C). September is the warmest month, exhibiting average temperatures of 69.8°F (21°C) at the peak and 56.5°F (13.6°C) at the base. Weather in September »Weather in October
October, like September, in San Bruno, California, is another refreshing autumn month, with an average temperature varying between 55.6°F (13.1°C) and 66.7°F (19.3°C). In October, San Bruno experiences a minor shift in meteorological conditions with average high-temperatures marked at a comfortable 66.7°F (19.3°C), closely mirroring the climate in September. Weather in October »Weather in November
The last month of the autumn, November, is another refreshing month in San Bruno, California, with an average temperature varying between 51.8°F (11°C) and 61°F (16.1°C). The arrival of November is marked by a minor reduction in average high-temperature, sliding from a comfortable 66.7°F (19.3°C) in October to a still enjoyable 61°F (16.1°C). Weather in November »Weather in December
December, the first month of the winter in San Bruno, is still a mild month, with an average temperature fluctuating between 47.7°F (8.7°C) and 55.8°F (13.2°C). San Bruno records the coldest temperatures in December, averaging a high of 55.8°F (13.2°C) and a low of 47.7°F (8.7°C). Weather in December »Updated: Jul 2, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
In San Bruno, during the entire year, the rain falls for 81.8 days and collects up to 13.46" (342mm) of precipitation.
February is the month with the most rainfall. Rain falls for 9 days and accumulates 2.72" (69mm) of precipitation.
The months with the lowest UV index are February, November and December, with an average maximum UV index of 3.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from PST to PDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from PDT to PST.
June has the longest days of the year, with an average of 14h and 42min of daylight.
The months with the highest UV index in San Bruno are June through September, with an average maximum UV index of 5.
July and August are months with the least rain when the rain falls for 2.2 days and typically aggregates up to 0.04" (1mm) of rain.
July has the most sunshine of the year, with an average of 11.8h of sunshine.
With an average relative humidity of 79%, August is the most humid month.
San Bruno's temperature records reveal September as the warmest month, marked by average highs of 69.8°F (21°C) and lows of 56.5°F (13.6°C).
October and November, with an average relative humidity of 71%, are the least humid months.
In San Bruno, December is the month with the lowest recorded average temperatures, measuring a high of 55.8°F (13.2°C) and a low of 47.7°F (8.7°C).
The month with the shortest days is December, with an average of 9h and 36min of daylight.
The month with the least sunshine is December, with an average of 5.8h of sunshine.
Average temperature
San Bruno, CA
The warmest month (with the highest average high temperature) is September (69.8°F).
The month with the lowest average high temperature is December (55.8°F).
The month with the highest average low temperature is September (56.5°F).
The coldest month (with the lowest average low temperature) is December (47.7°F).
Average pressure
San Bruno, CA
- Average pressure in January:
30.13"Hg - Average pressure in February:
30.08"Hg - Average pressure in March:
30.07"Hg - Average pressure in April:
30.04"Hg - Average pressure in May:
29.98"Hg - Average pressure in June:
29.93"Hg
- Average pressure in July:
29.93"Hg - Average pressure in August:
29.93"Hg - Average pressure in September:
29.92"Hg - Average pressure in October:
29.98"Hg - Average pressure in November:
30.07"Hg - Average pressure in December:
30.11"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
San Bruno, CA
- Average wind speed in January:
6.7mph - Average wind speed in February:
8mph - Average wind speed in March:
8.1mph - Average wind speed in April:
8.5mph - Average wind speed in May:
8.4mph - Average wind speed in June:
7.7mph
- Average wind speed in July:
6.5mph - Average wind speed in August:
6.3mph - Average wind speed in September:
6.3mph - Average wind speed in October:
6.5mph - Average wind speed in November:
6.5mph - Average wind speed in December:
7.4mph
The windiest month (with the highest average wind speed) is April (8.5mph).
The calmest months (with the lowest average wind speed) are August and September (6.3mph).
Average humidity
San Bruno, CA
The month with the highest relative humidity is August (79%).
The months with the lowest relative humidity are October and November (71%).
Average rainfall
San Bruno, CA
- Average rainfall in January:
2.2" - Average rainfall in February:
2.72" - Average rainfall in March:
2.28" - Average rainfall in April:
0.75" - Average rainfall in May:
0.67" - Average rainfall in June:
0.12"
- Average rainfall in July:
0.04" - Average rainfall in August:
0.04" - Average rainfall in September:
0.12" - Average rainfall in October:
0.71" - Average rainfall in November:
1.54" - Average rainfall in December:
2.28"
The wettest month (with the highest rainfall) is February (2.72").
The driest months (with the least rainfall) are July and August (0.04").
Average rainfall days
San Bruno, CA
- Average rainfall days in January:
10.8 days - Average rainfall days in February:
9 days - Average rainfall days in March:
13.3 days - Average rainfall days in April:
8.7 days - Average rainfall days in May:
6 days - Average rainfall days in June:
2.5 days
- Average rainfall days in July:
2.2 days - Average rainfall days in August:
2.2 days - Average rainfall days in September:
3.1 days - Average rainfall days in October:
5.5 days - Average rainfall days in November:
7.5 days - Average rainfall days in December:
11 days
The month with the highest number of rainy days is March (13.3 days).
The months with the least rainy days are July and August (2.2 days).
Average daylight / Average sunshine
San Bruno, CA
- Average daylight in January:
9h and 54min - Average daylight in February:
10h and 48min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 12min - Average daylight in May:
14h and 12min - Average daylight in June:
14h and 42min
- Average daylight in July:
14h and 30min - Average daylight in August:
13h and 36min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 12min - Average daylight in November:
10h and 12min - Average daylight in December:
9h and 36min
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 January:
6h and 0min - Average sunshine in February:
6h and 12min - Average sunshine in March:
7h and 42min - Average sunshine in April:
10h and 12min - Average sunshine in May:
10h and 24min - Average sunshine in June:
11h and 30min
- Average sunshine in July:
11h and 48min - Average sunshine in August:
11h and 30min - Average sunshine in September:
10h and 48min - Average sunshine in October:
7h and 0min - Average sunshine in November:
6h and 30min - Average sunshine in December:
5h and 48min
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
San Bruno, CA
- Average sunshine days in January:
19.8 days - Average sunshine days in February:
17.9 days - Average sunshine days in March:
16.3 days - Average sunshine days in April:
19.8 days - Average sunshine days in May:
22.2 days - Average sunshine days in June:
25.5 days
- Average sunshine days in July:
27.3 days - Average sunshine days in August:
25.5 days - Average sunshine days in September:
25.2 days - Average sunshine days in October:
23.5 days - Average sunshine days in November:
21.5 days - Average sunshine days in December:
19.1 days
The month with the most sunshine days is July (27.3 days).
The month with the least sunshine days is March (16.3 days).
Average UV index
San Bruno, CA
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, November and December (UV index 3).
Average cloud cover
San Bruno, CA
The month with the most cloud cover is March (Cloud cover 37).
The month with the least cloud cover is September (Cloud cover 16).
Average visibility
San Bruno, CA
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).
