Port Costa, CA Weather Forecast
Local 7-day forecast
Sunny
Track current conditions, temperature changes, wind, and the full daily outlook for Port Costa, CA in one place.
Sunny, with a high near 97. North northwest wind 2 to 12 mph, with gusts as high as 22 mph.
Local Weather Overview
This forecast page for Port Costa, CA is designed for quick trip planning, giving you a clean read on daytime highs, overnight lows, and changing conditions across the upcoming forecast window. Latest sync: Jun 9, 2026 10:20 PM PDT.
The active forecast window currently covers Jun 10 to Jun 16, 2026 for Port Costa, CA.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Jun 10 to Jun 16, 2026
- Latest sync
- Jun 9, 2026 10:20 PM PDT
- Forecast office
- MTR
- Source
- NOAA / NWS
Daily Outlook
This Week in Port Costa
Thursday looks like the warmest upcoming period in Port Costa at 99 degrees F.
Sunday Night is the coolest period ahead with temperatures near 55 degrees F.
The strongest winds are forecast for Wednesday Night at about 7 to 13 mph NNW.
The forecast from Jun 10 through Jun 16 stays mostly dry.
Forecast Details
- Last updated
- Jun 9, 2026 10:20 PM PDT
- Coverage
- 7 days
- Time zone
- America/Los_Angeles
- Forecast office
- MTR
- Radar station
- KDAX
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
Clear, with a low around 71. North northwest wind 7 to 13 mph, with gusts as high as 44 mph.
Sunny, with a high near 99. North wind 5 to 13 mph, with gusts as high as 37 mph.
Clear, with a low around 61. West wind 0 to 5 mph.
Sunny, with a high near 95.
Clear, with a low around 57.
Sunny, with a high near 95.
Clear, with a low around 57.
Sunny, with a high near 90.
Clear, with a low around 55.
Sunny, with a high near 89.
Mostly clear, with a low around 55.
Sunny, with a high near 90.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Wednesday
Jun 10
|
Sunny
|
97°F |
2 to 12 mph
NNW
|
|
Wednesday Night
Jun 10
|
Clear
|
71°F |
7 to 13 mph
NNW
|
|
Thursday
Jun 11
|
Sunny
|
99°F |
5 to 13 mph
N
|
|
Thursday Night
Jun 11
|
Clear
|
61°F |
0 to 5 mph
W
|
|
Friday
Jun 12
|
Sunny
|
95°F |
0 to 8 mph
W
|
|
Friday Night
Jun 12
|
Clear
|
57°F |
0 to 8 mph
WSW
|
|
Saturday
Jun 13
|
Sunny
|
95°F |
0 to 9 mph
SW
|
|
Saturday Night
Jun 13
|
Clear
|
57°F |
1 to 9 mph
WSW
|
|
Sunday
Jun 14
|
Sunny
|
90°F |
1 to 9 mph
WSW
|
|
Sunday Night
Jun 14
|
Clear
|
55°F |
1 to 9 mph
WSW
|
|
Monday
Jun 15
|
Sunny
|
89°F |
0 to 9 mph
SW
|
|
Monday Night
Jun 15
|
Mostly Clear
|
55°F |
0 to 9 mph
WSW
|
|
Tuesday
Jun 16
|
Sunny
|
90°F |
0 to 8 mph
SW
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Port Costa.