Port Costa
California, USA
Long-term weather forecast
Long-term weather forecast

Monthly weather forecast and climate
Port Costa, CA

January, like December, is a moderate winter month in Port Costa, California, with average temperature ranging between min 43°F (6.1°C) and max 56.5°F (13.6°C). In Port Costa, the average high-temperature is practically the same as in December - a still moderate 56.5°F (13.6°C). Weather in January »

The last month of the winter, February, is also a moderate month in Port Costa, California, with average temperature fluctuating between 59.2°F (15.1°C) and 44.1°F (6.7°C). In Port Costa, the average high-temperature is essentially the same as in January - a still mild 59.2°F (15.1°C). Weather in February »

March, the first month of the spring, in Port Costa, is an enjoyable month, with average temperature varying between 45°F (7.2°C) and 61.5°F (16.4°C). In Port Costa, the average high-temperature is relatively the same as in February - an enjoyable 61.5°F (16.4°C). Weather in March »

April, like March, in Port Costa, California, is another enjoyable spring month, with average temperature varying between 66.7°F (19.3°C) and 46.8°F (8.2°C). In April, the average high-temperature is almost the same as in March - a still comfortable 66.7°F (19.3°C). Weather in April »

The last month of the spring, May, is a pleasant month in Port Costa, California, with temperature in the range of an average high of 71.1°F (21.7°C) and an average low of 49.8°F (9.9°C). In Port Costa, the average high-temperature in May is almost the same as in April - an agreeable 71.1°F (21.7°C). Weather in May »

The first month of the summer, June, is a warm month in Port Costa, California, with average temperature ranging between min 54.1°F (12.3°C) and max 77.7°F (25.4°C). In Port Costa, the average high-temperature marginally rises, from an agreeable 71.1°F (21.7°C) in May, to a moderately hot 77.7°F (25.4°C). Weather in June »

July, the same as June, is another warm summer month in Port Costa, California, with temperature in the range of an average low of 55.4°F (13°C) and an average high of 80.1°F (26.7°C). The warmest months are July and September, with an average high-temperature of 80.1°F (26.7°C). Weather in July »

August, the last month of the summer, in Port Costa, is another warm month, with average temperature ranging between min 56.5°F (13.6°C) and max 79.7°F (26.5°C). In Port Costa, the average high-temperature in August is relatively the same as in July - a still warm 79.7°F (26.5°C). Weather in August »

The first month of the autumn, September, is still a warm month in Port Costa, California, with average temperature varying between 56.3°F (13.5°C) and 80.1°F (26.7°C). The warmest months are July and September, with an average high-temperature of 80.1°F (26.7°C). Weather in September »

October, like September, is an agreeable autumn month in Port Costa, California, with average temperature ranging between max 72.9°F (22.7°C) and min 54°F (12.2°C). In Port Costa, the average high-temperature in October slightly decreases, from a moderately hot 80.1°F (26.7°C) in September, to a pleasant 72.9°F (22.7°C). Weather in October »

November, the last month of the autumn, in Port Costa, is another comfortable month, with temperature in the range of an average low of 47.7°F (8.7°C) and an average high of 63°F (17.2°C). In November, the average high-temperature decreases, from a pleasant 72.9°F (22.7°C) in October, to a comfortable 63°F (17.2°C). Weather in November »

The first month of the winter, December, is also a moderate month in Port Costa, California, with average temperature ranging between min 43.2°F (6.2°C) and max 55.4°F (13°C). The coldest month is December, with an average high-temperature of 55.4°F (13°C) and an average low-temperature of 43.2°F (6.2°C). Weather in December »

How much does it rain in Port Costa?

Throughout the year, there are 56.9 rainfall days, and 4.88" (124mm) of precipitation is accumulated.

What is the month with the lowest UV index in Port Costa?

January, February, November and December, with an average maximum UV index of 3, are months with the lowest UV index in Port Costa.

What is the rainiest month in Port Costa?

The month with the most rainfall in Port Costa is February when the rain falls for 6.8 days and typically aggregates up to 1.14" (29mm) of precipitation.

What is the most humid month in Port Costa?

March is the most humid month in Port Costa, with an average relative humidity of 75%.

When are the longest days in Port Costa?

June has the longest days of the year in Port Costa, with an average of 14.8h of daylight.

When is the highest UV index in Port Costa?

With an average maximum UV index of 6, June is the month with the highest UV index.

What is the warmest month in Port Costa?

July and September, with an average high-temperature of 80.1°F (26.7°C), are warmest months in Port Costa.

What is the driest month in Port Costa?

July and August are months with the least rain in Port Costa, California, when the rain falls for 1.5 days and typically aggregates up to 0.04" (1mm) of rain.

What month has the most sunshine in Port Costa?

With an average of 12h of sunshine, July has the most sunshine of the year.

What are the least humid months in Port Costa?

September and October, with an average relative humidity of 60%, are the least humid months in Port Costa, California.

What is the coldest month in Port Costa?

The coldest month in Port Costa, California, is December, with an average high-temperature of 55.4°F (13°C) and an average low-temperature of 43.2°F (6.2°C).

What is the month with the shortest days in Port Costa?

With an average of 9.6h of daylight, December has the shortest days of the year in Port Costa.

What is the month with the least sunshine in Port Costa?

December has the least sunshine of the year, with an average of 5.7h of sunshine.
Average temperature - Port Costa, CA
Average humidity - Port Costa, CA
Average rainfall - Port Costa, CA

The wettest month (with the highest rainfall) is February (1.14").
The driest months (with the least rainfall) are July and August (0.04").

Average rainfall days - Port Costa, CA
Average daylight / Average sunshine - Port Costa, CA

The month with the longest days is June (Average daylight: 14.8h).
The month with the shortest days is December (Average daylight: 9.6h).

The month with the most sunshine is July (Average sunshine: 12h).
The month with the least sunshine is December (Average sunshine: 5.7h).