Monthly outlook for Altamont, CA: average high 75.8°, average low 52.4°. That is 1.5° above the climate normal for October. Precipitation is expected on 0 days (about 0.0 inches), against a normal of 2 days and 0.6 inches. The warmest day looks like 17 October (90.2°), the coolest 13 October (45.9°).
75.8°/52.4°
Average high / low
+1.5°
Above normal
0 / 2
Wet days / normal
0.0 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
13 October – 22 October
75°
74.5°
+0.3°
23 October – 1 November
77.2°
70.1°
+4°
2 November – 11 November
at normal
66.5°
—
October records over 66 years
104.5°2 October 2024All-time high
37.6°30 October 1971All-time low
Climate normals and records are computed from the nearest reference point — Livermore (7 mi).
Wed, 1476° / 47°0
76 °
Altamont, Wednesday, 14 October
Clear. High 76°, low 47°.
Pressure30.12 inHg
Wind3 mph N
Humidity20%
Visibility6.2 mi
Dew point28°
Thu, 1583° / 55°0
83 °
Altamont, Thursday, 15 October
Clear. High 83°, low 55°.
Pressure30.12 inHg
Wind3.8 mph NE
Humidity18%
Visibility6.2 mi
Dew point29°
Fri, 1686° / 60°0
86 °
Altamont, Friday, 16 October
Clear. High 86°, low 60°.
Pressure30.09 inHg
Wind3.5 mph NE
Humidity17%
Visibility6.2 mi
Dew point32°
Sat, 1790° / 62°0
90 °
Altamont, Saturday, 17 October
Clear. High 90°, low 62°.
Pressure30.03 inHg
Wind4.2 mph SW
Humidity15%
Visibility—
Dew point28°
Sun, 1871° / 52°0
71 °
Altamont, Sunday, 18 October
Clear. High 71°, low 52°.
Pressure30.03 inHg
Wind14.4 mph SW
Humidity59%
Visibility—
Dew point50°
Mon, 1964° / 50°0
64 °
Altamont, Monday, 19 October
Overcast. High 64°, low 50°.
Pressure30.00 inHg
Wind16.3 mph SW
Humidity68%
Visibility—
Dew point49°
Tue, 2064° / 47°0
64 °
Altamont, Tuesday, 20 October
Clear. High 64°, low 47°.
Pressure30.00 inHg
Wind10.6 mph NW
Humidity46%
Visibility—
Dew point35°
Wed, 2171° / 48°0
71 °
Altamont, Wednesday, 21 October
Clear. High 71°, low 48°.
Pressure30.03 inHg
Wind13.7 mph N
Humidity33%
Visibility—
Dew point30°
Thu, 2273° / 51°0
73 °
Altamont, Thursday, 22 October
Clear. High 73°, low 51°.
Pressure30.12 inHg
Wind7.5 mph N
Humidity19%
Visibility—
Dew point20°
Fri, 2376° / 52°0
76 °
Altamont, Friday, 23 October
Clear. High 76°, low 52°.
Pressure30.18 inHg
Wind14.7 mph N
Humidity20%
Visibility—
Dew point21°
Sat, 2475° / 50°0
75 °
Altamont, Saturday, 24 October
Clear. High 75°, low 50°.
Pressure30.27 inHg
Wind5.8 mph N
Humidity13%
Visibility—
Dew point11°
Sun, 2580° / 55°0
80 °
Altamont, Sunday, 25 October
Clear. High 80°, low 55°.
Pressure30.09 inHg
Wind5.8 mph N
Humidity10%
Visibility—
Dew point9°
Mon, 2677° / 54°0
77 °
Altamont, Monday, 26 October
Partly cloudy. High 77°, low 54°.
Pressure29.94 inHg
Wind5.5 mph NE
Humidity14%
Visibility—
Dew point15°
Tue, 2778° / 54°0
78 °
Altamont, Tuesday, 27 October
Partly cloudy. High 78°, low 54°.
Pressure30.00 inHg
Wind6.2 mph W
Humidity27%
Visibility—
Dew point30°
Wed, 2877° / 54°0
77 °
Altamont, Wednesday, 28 October
Partly cloudy. High 77°, low 54°.
Pressure30.03 inHg
Wind4.8 mph NE
Humidity36%
Visibility—
Dew point38°
From day 17 onward the outlook is built from 60-year climate statistics
Thu, 2969° / 50°0.05
69 °
Altamont, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high69°
Average low50°
Average precipitation0.05 in
Chance of precipitation17%
Record high82° (1965)
Record low39° (1971)
Fri, 3068° / 50°0.06
68 °
Altamont, Friday, 30 October
Climate normal for this date — 60-year average.
Average high68°
Average low50°
Average precipitation0.06 in
Chance of precipitation15%
Record high82° (1965)
Record low38° (1971)
Sat, 3169° / 50°0.03
69 °
Altamont, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high69°
Average low50°
Average precipitation0.03 in
Chance of precipitation13%
Record high82° (2015)
Record low41° (2019)
Sun, 0169° / 51°0.04
69 °
Altamont, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high69°
Average low51°
Average precipitation0.04 in
Chance of precipitation12%
Record high82° (1967)
Record low40° (1984)
Mon, 0269° / 51°0.03
69 °
Altamont, Monday, 2 November
Climate normal for this date — 60-year average.
Average high69°
Average low51°
Average precipitation0.03 in
Chance of precipitation10%
Record high82° (2020)
Record low40° (2003)
Tue, 0369° / 51°0.03
69 °
Altamont, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high69°
Average low51°
Average precipitation0.03 in
Chance of precipitation10%
Record high83° (2018)
Record low38° (2022)
Wed, 0469° / 50°0.02
69 °
Altamont, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high69°
Average low50°
Average precipitation0.02 in
Chance of precipitation10%
Record high81° (2010)
Record low40° (1973)
Thu, 0568° / 49°0.05
68 °
Altamont, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high68°
Average low49°
Average precipitation0.05 in
Chance of precipitation12%
Record high83° (2020)
Record low40° (2011)
Fri, 0667° / 50°0.04
67 °
Altamont, Friday, 6 November
Climate normal for this date — 60-year average.
Average high67°
Average low50°
Average precipitation0.04 in
Chance of precipitation17%
Record high81° (2012)
Record low40° (1998)
Sat, 0766° / 49°0.06
66 °
Altamont, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high66°
Average low49°
Average precipitation0.06 in
Chance of precipitation22%
Record high80° (1991)
Record low40° (2017)
Sun, 0865° / 48°0.06
65 °
Altamont, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high65°
Average low48°
Average precipitation0.06 in
Chance of precipitation20%
Record high78° (1978)
Record low39° (1982)
Mon, 0965° / 47°0.06
65 °
Altamont, Monday, 9 November
Climate normal for this date — 60-year average.
Average high65°
Average low47°
Average precipitation0.06 in
Chance of precipitation18%
Record high78° (1976)
Record low38° (1982)
Tue, 1064° / 48°0.09
64 °
Altamont, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high64°
Average low48°
Average precipitation0.09 in
Chance of precipitation30%
Record high78° (2019)
Record low38° (2020)
Wed, 1164° / 48°0.08
64 °
Altamont, Wednesday, 11 November
Climate normal for this date — 60-year average.
Average high64°
Average low48°
Average precipitation0.08 in
Chance of precipitation28%
Record high78° (1990)
Record low39° (1985)
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 Altamont, 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 Altamont, 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.