Monthly outlook for Diamond Bar, CA: average high 67.1°, average low 55.4°. That is 1.1° below the climate normal for November. Precipitation is expected on 5 days (about 1.7 inches), against a normal of 2 days and 0.9 inches. The warmest day looks like 15 November (71°), the coolest 18 November (44.9°).
67.1°/55.4°
Average high / low
−1.1°
Below normal
5 / 2
Wet days / normal
1.7 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
13 November – 22 November
65.8°
69.9°
-2.3°
23 November – 2 December
69.1°
67°
+1.2°
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, 1471° / 56°0.28
71 °
Diamond Bar, Saturday, 14 November
Rain. High 71°, low 56°.
Pressure29.91 inHg
Wind2.2 mph E
Humidity57%
Visibility6.2 mi
Dew point53°
Sun, 1571° / 53°0
71 °
Diamond Bar, Sunday, 15 November
Mostly clear. High 71°, low 53°.
Pressure30.06 inHg
Wind1 mph NW
Humidity56%
Visibility6.2 mi
Dew point53°
Mon, 1669° / 58°0.26
69 °
Diamond Bar, Monday, 16 November
Rain. High 69°, low 58°.
Pressure30.03 inHg
Wind3 mph W
Humidity62%
Visibility6.2 mi
Dew point55°
Tue, 1764° / 47°0.2
64 °
Diamond Bar, Tuesday, 17 November
Light rain. High 64°, low 47°.
Pressure29.97 inHg
Wind9.2 mph SW
Humidity72%
Visibility—
Dew point49°
Wed, 1864° / 45°0
64 °
Diamond Bar, Wednesday, 18 November
Overcast. High 64°, low 45°.
Pressure30.15 inHg
Wind4.6 mph E
Humidity52%
Visibility—
Dew point40°
Thu, 1960° / 56°0.56
60 °
Diamond Bar, Thursday, 19 November
Rain. High 60°, low 56°.
Pressure29.94 inHg
Wind12.1 mph SW
Humidity77%
Visibility—
Dew point50°
Fri, 2061° / 51°0
61 °
Diamond Bar, Friday, 20 November
Clear. High 61°, low 51°.
Pressure30.00 inHg
Wind8.5 mph SW
Humidity27%
Visibility—
Dew point22°
Sat, 2164° / 53°0
64 °
Diamond Bar, Saturday, 21 November
Overcast. High 64°, low 53°.
Pressure30.09 inHg
Wind7.3 mph E
Humidity25%
Visibility—
Dew point23°
Sun, 2267° / 56°0
67 °
Diamond Bar, Sunday, 22 November
Clear. High 67°, low 56°.
Pressure30.09 inHg
Wind3.7 mph W
Humidity19%
Visibility—
Dew point19°
Mon, 2367° / 59°0
67 °
Diamond Bar, Monday, 23 November
Overcast. High 67°, low 59°.
Pressure30.03 inHg
Wind4.1 mph SW
Humidity20%
Visibility—
Dew point21°
Tue, 2470° / 58°0
70 °
Diamond Bar, Tuesday, 24 November
Overcast. High 70°, low 58°.
Pressure30.00 inHg
Wind5.3 mph SW
Humidity22%
Visibility—
Dew point25°
Wed, 2567° / 59°0.04
67 °
Diamond Bar, Wednesday, 25 November
Light rain. High 67°, low 59°.
Pressure30.06 inHg
Wind5.1 mph SW
Humidity26%
Visibility—
Dew point29°
Thu, 2670° / 58°0.04
70 °
Diamond Bar, Thursday, 26 November
Light rain. High 70°, low 58°.
Pressure30.09 inHg
Wind7.9 mph W
Humidity50%
Visibility—
Dew point45°
Fri, 2771° / 59°0
71 °
Diamond Bar, Friday, 27 November
Partly cloudy. High 71°, low 59°.
Pressure30.15 inHg
Wind6.2 mph W
Humidity27%
Visibility—
Dew point30°
Sat, 2869° / 59°0
69 °
Diamond Bar, Saturday, 28 November
Overcast. High 69°, low 59°.
Pressure30.09 inHg
Wind4.9 mph SW
Humidity45%
Visibility—
Dew point42°
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.