Diamond Bar, CA Weather Forecast
Local 7-day forecast
Sunny
Track current conditions, temperature changes, wind, and the full daily outlook for Diamond Bar, CA in one place.
Sunny, with a high near 83. Southwest wind 0 to 10 mph, with gusts as high as 20 mph.
Local Weather Overview
This forecast page for Diamond Bar, 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: Jul 17, 2026 7:15 AM PDT.
The active forecast window currently covers Jul 18 to Jul 23, 2026 for Diamond Bar, CA.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Jul 18 to Jul 23, 2026
- Latest sync
- Jul 17, 2026 7:15 AM PDT
- Forecast office
- LOX
- Source
- NOAA / NWS
Daily Outlook
This Week in Diamond Bar
Wednesday looks like the warmest upcoming period in Diamond Bar at 92 degrees F.
Saturday Night is the coolest period ahead with temperatures near 63 degrees F.
The strongest winds are forecast for Saturday at about 0 to 10 mph SW.
The forecast from Jul 18 through Jul 23 stays mostly dry.
Forecast Details
- Last updated
- Jul 17, 2026 7:15 AM PDT
- Coverage
- 6 days
- Time zone
- America/Los_Angeles
- Forecast office
- LOX
- Radar station
- KSOX
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
Partly cloudy, with a low around 63. Southwest wind 0 to 10 mph.
Mostly sunny, with a high near 84.
Partly cloudy, with a low around 63.
Mostly sunny, with a high near 83.
Mostly clear, with a low around 64.
Sunny, with a high near 89.
Mostly clear, with a low around 65.
Sunny, with a high near 92.
Partly cloudy, with a low around 66.
Mostly sunny, with a high near 92.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Saturday
Jul 18
|
Sunny
|
83°F |
0 to 10 mph
SW
|
|
Saturday Night
Jul 18
|
Partly Cloudy
|
63°F |
0 to 10 mph
SW
|
|
Sunday
Jul 19
|
Mostly Sunny
|
84°F |
0 to 10 mph
SW
|
|
Sunday Night
Jul 19
|
Partly Cloudy
|
63°F |
0 to 10 mph
SW
|
|
Monday
Jul 20
|
Mostly Sunny
|
83°F |
0 to 10 mph
SW
|
|
Monday Night
Jul 20
|
Mostly Clear
|
64°F |
0 to 10 mph
SW
|
|
Tuesday
Jul 21
|
Sunny
|
89°F |
0 to 10 mph
SW
|
|
Tuesday Night
Jul 21
|
Mostly Clear
|
65°F |
0 to 10 mph
SW
|
|
Wednesday
Jul 22
|
Sunny
|
92°F |
0 to 10 mph
SW
|
|
Wednesday Night
Jul 22
|
Partly Cloudy
|
66°F |
0 to 10 mph
SW
|
|
Thursday
Jul 23
|
Mostly Sunny
|
92°F |
0 to 10 mph
WSW
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Diamond Bar.
