Diamond Bar, CA Weather Forecast for 5-Days

Updated: Thu Nov 6th 2025 8:15 PM PST

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Diamond Bar, CA Weather – 11-6 – Sunny
75° / 51°
Sunny
Sunshine is in the forecast for Diamond Bar, with a high of 75°F and a low of 51°F. Winds will be light at 6mph and gusts of 6.1mph at 8 PM. The humidity will be on the higher side, averaging about 75%, the maximum being 91% at 9 PM and 77% being its lowest at 8 PM. Barometric pressure is its highest of 30.04inHg at 8 PM, a lowest point of 30.02inHg at 11 PM with an avg 30.03inHg.
Diamond Bar, CA Weather – 11-7 – Sunny
84° / 53°
Sunny
Diamond Bar could see a sunny day with daytime highs of 84°F and nighttime lows near 53°F. Winds will be light at 7mph and gusts of 10mph at 6 PM. Humidity levels should be comfortable, sitting around 59% on average, the maximum being 91% at 5 AM and 33% being its lowest at 1 PM. Barometric pressure is its highest of 30.01inHg at 12 AM, a lowest point of 29.87inHg at 4 PM with an avg 29.94inHg.
Diamond Bar, CA Weather – 11-8 – Sunny
87° / 62°
Sunny
Daytime highs will reach 87°F with lows dropping to 62°F in Diamond Bar, where bright and sunny conditions. Winds will be light at 7mph and gusts of 10.7mph at 5 PM. Humidity levels should be comfortable, sitting around 44% on average, the maximum being 58% at 11 PM and 27% being its lowest at 11 AM. Barometric pressure is its highest of 29.99inHg at 10 PM, a lowest point of 29.9inHg at 4 AM with an avg 29.93inHg.
Diamond Bar, CA Weather – 11-9 – Sunny
92° / 62°
Sunny
Sunshine is in the forecast for Diamond Bar, with a high of 92°F and a low of 62°F. Winds will be light at 6mph and gusts of 8.6mph at 4 PM. The air will be relatively dry with average humidity levels below 30%, the maximum being 54% at 11 PM and 13% being its lowest at 2 PM. Barometric pressure is its highest of 30.1inHg at 10 PM, a lowest point of 30inHg at 12 AM with an avg 30.04inHg.
Diamond Bar, CA Weather – 11-10 – Sunny
86° / 71°
Sunny
Diamond Bar may see sunshine, with daytime highs of 86°F and overnight lows near 71°F. Winds will be light at 7mph and gusts of 10.8mph at 5 PM. The air will be relatively dry with average humidity levels below 30%, the maximum being 27% at 12 AM and 11% being its lowest at 3 PM. Barometric pressure is its highest of 30.12inHg at 9 AM, a lowest point of 30.01inHg at 4 PM with an avg 30.07inHg.
Diamond Bar, CA Weather – 11-11 – Partly Cloudy
81° / 69°
Partly Cloudy
In Diamond Bar, it will be cloudy with highs near 81°F and lows around 69°F. Winds will be light at 6mph and gusts of 8.9mph at 5 PM. The air will be relatively dry with average humidity levels below 30%, the maximum being 34% at 11 PM and 16% being its lowest at 11 AM. Barometric pressure is its highest of 30.06inHg at 11 AM, a lowest point of 29.99inHg at 4 PM with an avg 30.03inHg.

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