Port Costa, CA Weather
Port Costa, CA climate is warm during summer when temperatures tend to be in the 70's and cold during winter when temperatures tend to be in the 40's.
The warmest month of the year is July with an average maximum temperature of 87.40 degrees Fahrenheit, while the coldest month of the year is December with an average minimum temperature of 38.50 degrees Fahrenheit.
Temperature variations between night and day tend to be relatively big during summer with a difference that can reach 32 degrees Fahrenheit, and fairly limited during winter with an average difference of 16 degrees Fahrenheit.
The annual average precipitation at Port Costa is 19.58 Inches. Winter months tend to be wetter than summer months. The wettest month of the year is January with an average rainfall of 4.25 Inches.
Weather Data
Current Conditions
|
Fair, 51°F | Humidity: 80% | Dewpoint: 45°F |
| Wind Speed: N 4.6 MPH (4 KT) | Heat Index: 51°F | ||
| Barometer: 30.23 in. | Wind Chill: 50°F |
Weather Forecast
 | Hi: 65°F | Today: Sunny. Highs in the mid 60s. Northeast winds 5 to 10 mph. |
| Lo: 41°F | ||
| Hi: 66°F | Wednesday: Sunny. Highs in the mid 60s to lower 70s. Northeast winds around 5 mph. |
| Lo: 41°F | ||
| Hi: 65°F | Thanksgiving day: Sunny. Highs in the mid 60s. Light winds. |
| Lo: 41°F | ||
 | Hi: 65°F | Friday: Partly cloudy. Highs in the mid 60s. |
| Lo: 39°F | ||
| Hi: 65°F | Saturday: Mostly clear. Lows in the upper 30s. Highs in the mid 60s. |
| Lo: 39°F | ||
| Hi: 65°F | Sunday: Mostly clear. Lows in the upper 30s. Highs in the mid 60s. |
| Lo: 39°F | ||
| Hi: 65°F | Monday: Mostly clear. Lows in the upper 30s. Highs in the mid 60s. |
| Lo: 39°F |
Moon, Sunrise and Sunset
 |
Moon Phase: Waxing Gibbous Moon | Civil Twilight: 6:29 AM PST |
Sunrise: 6:58 AM PST |
| Sunset: 4:51 PM PST |
Civil Twilight: 5:20 PM PST |
Normal Climate
Normal Temperatures
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Max °F | 53.7 | 59.5 | 64.3 | 70.9 | 77.7 | 83.9 | 87.4 | 86.6 | 83.3 | 75.5 | 62.7 | 54.5 | 71.7 |
| Mean °F | 46.3 | 50.7 | 54.3 | 58.5 | 63.7 | 68.9 | 71.2 | 70.8 | 68.6 | 62.5 | 53.0 | 46.5 | 59.6 |
| Min °F | 38.8 | 41.8 | 44.3 | 46.1 | 49.7 | 53.8 | 54.9 | 55.0 | 53.8 | 49.5 | 43.3 | 38.5 | 47.5 |
Normal Precipitation
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Inch | 4.25 | 3.81 | 3.24 | 1.04 | 0.46 | 0.12 | 0.02 | 0.08 | 0.24 | 0.94 | 2.59 | 2.79 | 19.58 |
