Monthly outlook for Diamond Bar, CA: average high 69.3°, average low 57.9°. That is 0.2° above the climate normal for November. Precipitation is expected on 7 days (about 2.3 inches), against a normal of 2 days and 0.9 inches. The warmest day looks like 22 November (74.8°), the coolest 18 November (47°).
69.3°/57.9°
Average high / low
+0.2°
Above normal
7 / 2
Wet days / normal
2.3 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
13 November – 22 November
69°
69.9°
-0.5°
23 November – 2 December
69.8°
67°
+1.6°
3 December – 12 December
at normal
65°
—
November records over 66 years
94.6°5 November 2020All-time high
24.6°19 November 1964All-time low
Climate normals and records are computed from the nearest reference point — Pomona (5 mi).
Sat, 1470° / 59°0.15
70 °
Diamond Bar, Saturday, 14 November
Rain. High 70°, low 59°.
Pressure29.91 inHg
Wind2.1 mph SE
Humidity59%
Visibility6.2 mi
Dew point54°
Sun, 1572° / 56°0
72 °
Diamond Bar, Sunday, 15 November
Clear. High 72°, low 56°.
Pressure30.06 inHg
Wind2.3 mph NW
Humidity54%
Visibility6.2 mi
Dew point52°
Mon, 1669° / 57°0.49
69 °
Diamond Bar, Monday, 16 November
Heavy rain. High 69°, low 57°.
Pressure30.03 inHg
Wind1.5 mph NW
Humidity76%
Visibility6.2 mi
Dew point57°
Tue, 1762° / 51°0.06
62 °
Diamond Bar, Tuesday, 17 November
Light rain. High 62°, low 51°.
Pressure30.00 inHg
Wind0.5 mph S
Humidity56%
Visibility6.2 mi
Dew point42°
Wed, 1866° / 47°0
66 °
Diamond Bar, Wednesday, 18 November
Overcast. High 66°, low 47°.
Pressure30.15 inHg
Wind4.1 mph E
Humidity51%
Visibility—
Dew point42°
Thu, 1966° / 55°0.65
66 °
Diamond Bar, Thursday, 19 November
Heavy rain. High 66°, low 55°.
Pressure30.00 inHg
Wind8.2 mph W
Humidity69%
Visibility—
Dew point51°
Fri, 2069° / 60°0.14
69 °
Diamond Bar, Friday, 20 November
Rain. High 69°, low 60°.
Pressure30.03 inHg
Wind6 mph SE
Humidity53%
Visibility—
Dew point47°
Sat, 2174° / 60°0
74 °
Diamond Bar, Saturday, 21 November
Mostly clear. High 74°, low 60°.
Pressure30.09 inHg
Wind6.3 mph SE
Humidity12%
Visibility—
Dew point13°
Sun, 2275° / 62°0
75 °
Diamond Bar, Sunday, 22 November
Partly cloudy. High 75°, low 62°.
Pressure30.12 inHg
Wind3.8 mph W
Humidity13%
Visibility—
Dew point16°
Mon, 2372° / 63°0
72 °
Diamond Bar, Monday, 23 November
Overcast. High 72°, low 63°.
Pressure30.06 inHg
Wind6.6 mph W
Humidity18%
Visibility—
Dew point23°
Tue, 2470° / 60°0
70 °
Diamond Bar, Tuesday, 24 November
Clear. High 70°, low 60°.
Pressure30.06 inHg
Wind6.3 mph SW
Humidity32%
Visibility—
Dew point35°
Wed, 2570° / 61°0
70 °
Diamond Bar, Wednesday, 25 November
Overcast. High 70°, low 61°.
Pressure30.12 inHg
Wind6.6 mph SW
Humidity50%
Visibility—
Dew point46°
Thu, 2668° / 59°0.46
68 °
Diamond Bar, Thursday, 26 November
Rain. High 68°, low 59°.
Pressure30.09 inHg
Wind14 mph W
Humidity67%
Visibility—
Dew point51°
Fri, 2770° / 58°0
70 °
Diamond Bar, Friday, 27 November
Clear. High 70°, low 58°.
Pressure30.09 inHg
Wind4.5 mph NE
Humidity33%
Visibility—
Dew point34°
Sat, 2869° / 61°0
69 °
Diamond Bar, Saturday, 28 November
Partly cloudy. High 69°, low 61°.
Pressure30.06 inHg
Wind6.5 mph SW
Humidity35%
Visibility—
Dew point37°
From day 17 onward the outlook is built from 60-year climate statistics
Sun, 2965° / 46°0.13
65 °
Diamond Bar, Sunday, 29 November
Climate normal for this date — 60-year average.
Average high65°
Average low46°
Average precipitation0.13 in
Chance of precipitation17%
Record high82° (2021)
Record low32° (1975)
Mon, 3066° / 46°0.07
66 °
Diamond Bar, Monday, 30 November
Climate normal for this date — 60-year average.
Average high66°
Average low46°
Average precipitation0.07 in
Chance of precipitation20%
Record high82° (2021)
Record low34° (2004)
Tue, 0166° / 45°0.02
66 °
Diamond Bar, Tuesday, 1 December
Climate normal for this date — 60-year average.
Average high66°
Average low45°
Average precipitation0.02 in
Chance of precipitation8%
Record high82° (2021)
Record low34° (2004)
Wed, 0266° / 45°0.03
66 °
Diamond Bar, Wednesday, 2 December
Climate normal for this date — 60-year average.
Average high66°
Average low45°
Average precipitation0.03 in
Chance of precipitation13%
Record high81° (2017)
Record low36° (2004)
Thu, 0366° / 46°0.09
66 °
Diamond Bar, Thursday, 3 December
Climate normal for this date — 60-year average.
Average high66°
Average low46°
Average precipitation0.09 in
Chance of precipitation13%
Record high79° (1979)
Record low37° (2016)
Fri, 0466° / 45°0.1
66 °
Diamond Bar, Friday, 4 December
Climate normal for this date — 60-year average.
Average high66°
Average low45°
Average precipitation0.1 in
Chance of precipitation18%
Record high84° (1979)
Record low34° (2004)
Sat, 0566° / 45°0.08
66 °
Diamond Bar, Saturday, 5 December
Climate normal for this date — 60-year average.
Average high66°
Average low45°
Average precipitation0.08 in
Chance of precipitation18%
Record high82° (1979)
Record low32° (1972)
Sun, 0666° / 46°0.13
66 °
Diamond Bar, Sunday, 6 December
Climate normal for this date — 60-year average.
Average high66°
Average low46°
Average precipitation0.13 in
Chance of precipitation15%
Record high83° (1979)
Record low31° (1978)
Mon, 0765° / 46°0.13
65 °
Diamond Bar, Monday, 7 December
Climate normal for this date — 60-year average.
Average high65°
Average low46°
Average precipitation0.13 in
Chance of precipitation28%
Record high80° (1979)
Record low27° (1978)
Tue, 0865° / 45°0.03
65 °
Diamond Bar, Tuesday, 8 December
Climate normal for this date — 60-year average.
Average high65°
Average low45°
Average precipitation0.03 in
Chance of precipitation18%
Record high82° (2015)
Record low28° (1978)
Wed, 0965° / 44°0.03
65 °
Diamond Bar, Wednesday, 9 December
Climate normal for this date — 60-year average.
Average high65°
Average low44°
Average precipitation0.03 in
Chance of precipitation12%
Record high82° (2017)
Record low28° (1972)
Thu, 1065° / 44°0.03
65 °
Diamond Bar, Thursday, 10 December
Climate normal for this date — 60-year average.
Average high65°
Average low44°
Average precipitation0.03 in
Chance of precipitation8%
Record high82° (2017)
Record low32° (1971)
Fri, 1164° / 45°0.07
64 °
Diamond Bar, Friday, 11 December
Climate normal for this date — 60-year average.
Average high64°
Average low45°
Average precipitation0.07 in
Chance of precipitation18%
Record high80° (2025)
Record low31° (1972)
Sat, 1263° / 43°0.06
63 °
Diamond Bar, Saturday, 12 December
Climate normal for this date — 60-year average.
Average high63°
Average low43°
Average precipitation0.06 in
Chance of precipitation13%
Record high80° (1988)
Record low28° (1972)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Diamond Bar, CA are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Diamond Bar, CA since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.