See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
17°
Mostly Clear
Feels Like: 17°
Min: 17°
Max: 27°
The next few hours will be mostly clear, with today reaching 27°C and dropping to 16°C. The coming days will be clear
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:40
Sunrise
18:50
Sunset
Moon
Waxing Crescent
12:16
Moonrise
21:20
Moonset
Daily Forecast
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Thursday
Friday
Saturday
Sunday
Monday
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Friday
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Humidity
Weather in Diamond Bar today, September 16, 2026
Diamond Bar stays under cloudy skies on September 16, 2026, with only brief brighter breaks. Plan for a day that feels grey more often than open. The morning sky stays heavily clouded, with cover near 100% around 06:00. Grey conditions set the early tone before any later change.
Expect highs of 27°C and cooler readings close to 17°C. The air stays humid, with relative humidity between 48% and 94% and the peak around 23:00. Expect gentle winds, highest near 16:00 at 4.6 km/h.
Through the afternoon skies look more workable, with cloud near 29% around 23:00. Later outdoor plans have a clearer window than the morning may have suggested. Horizontal visibility sits around 16.1 km, briefly nearer 15.9 km. Expect sunrise at 06:40, sunset at 18:50, and 12 hours 9 minutes of sunlight today overall.
In short, cloud leads the story in Diamond Bar on September 16, 2026; expect limited sun and a peak around 27°C.
Frequently asked questions about weather in Diamond Bar
How warm does it get in Diamond Bar?
The warmest month in Diamond Bar is August, with average high temperatures of 31°C. The average temperature during this period is around 25°C.
How cold does it get in Diamond Bar?
The coldest month in Diamond Bar is January, with average low temperatures of 7°C. The average temperature during this period is around 12°C.
What is the wettest time of year in Diamond Bar?
The wettest month in Diamond Bar is January, with an average of 94mm of precipitation.
What is the driest time of year in Diamond Bar?
The driest month in Diamond Bar is July, with an average of 1mm of precipitation.
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