As of 20:46 PDT

Weather in Alto, CA

59°

Alto, Friday, 9 October, 20:46

Partly cloudy. Feels like 58°. High 78°, low 56°.

Pressure29.71 inHg

Wind13 mph W

Humidity81%

Visibility4.4 mi

Dew point53°

See detailed hourly forecast

Monthly outlook for Alto, CA: average high 66.1°, average low 52.6°. That is 2° below 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 9 October (77.7°), the coolest 11 October (44.4°).

66.1°/52.6°

Average high / low

−2°

Below normal

0 / 2

Wet days / normal

0.0 in

Precipitation this month

Ten-day blocks vs climate normal

Period	Forecast high	Normal	Difference
9 October – 18 October	67.7°	70.5°	-1.5°
19 October – 28 October	63.4°	68°	-2.6°
29 October – 7 November	at normal	65.6°	—

October records over 66 years

98.1°6 October 2024All-time high

41.2°31 October 1989All-time low

Climate normals and records are computed from the nearest reference point — Marin City (2 mi).

Sat, 1068° / 48°

68 °

Alto, Saturday, 10 October

Clear. High 68°, low 48°.

Pressure29.68 inHg

Wind9.4 mph W

Humidity60%

Visibility6.2 mi

Dew point49°

Sun, 1167° / 44°

67 °

Alto, Sunday, 11 October

Clear. High 67°, low 44°.

Pressure29.50 inHg

Wind4.4 mph SW

Humidity49%

Visibility6.2 mi

Dew point47°

Mon, 1264° / 50°

64 °

Alto, Monday, 12 October

Clear. High 64°, low 50°.

Pressure29.85 inHg

Wind1.7 mph S

Humidity51%

Visibility6.2 mi

Dew point46°

Tue, 1369° / 46°

69 °

Alto, Tuesday, 13 October

Mostly clear. High 69°, low 46°.

Pressure30.00 inHg

Wind1.2 mph E

Humidity35%

Visibility6.2 mi

Dew point35°

Wed, 1468° / 47°

68 °

Alto, Wednesday, 14 October

Clear. High 68°, low 47°.

Pressure30.15 inHg

Wind4.5 mph SW

Humidity55%

Visibility—

Dew point44°

Thu, 1568° / 49°

68 °

Alto, Thursday, 15 October

Clear. High 68°, low 49°.

Pressure30.12 inHg

Wind8.6 mph SW

Humidity44%

Visibility—

Dew point40°

Fri, 1666° / 58°

66 °

Alto, Friday, 16 October

Clear. High 66°, low 58°.

Pressure30.09 inHg

Wind7.7 mph W

Humidity45%

Visibility—

Dew point41°

Sat, 1765° / 57°

65 °

Alto, Saturday, 17 October

Clear. High 65°, low 57°.

Pressure30.03 inHg

Wind8.1 mph SW

Humidity59%

Visibility—

Dew point48°

Sun, 1863° / 55°

63 °

Alto, Sunday, 18 October

Clear. High 63°, low 55°.

Pressure29.94 inHg

Wind7.2 mph SW

Humidity72%

Visibility—

Dew point50°

Mon, 1961° / 55°

61 °

Alto, Monday, 19 October

Partly cloudy. High 61°, low 55°.

Pressure29.97 inHg

Wind9.8 mph W

Humidity58%

Visibility—

Dew point46°

Tue, 2063° / 54°

63 °

Alto, Tuesday, 20 October

Overcast. High 63°, low 54°.

Pressure30.03 inHg

Wind7.6 mph W

Humidity56%

Visibility—

Dew point42°

Wed, 2163° / 57°

63 °

Alto, Wednesday, 21 October

Clear. High 63°, low 57°.

Pressure30.06 inHg

Wind8.5 mph W

Humidity52%

Visibility—

Dew point43°

Thu, 2263° / 52°

63 °

Alto, Thursday, 22 October

Clear. High 63°, low 52°.

Pressure30.09 inHg

Wind9.6 mph NW

Humidity65%

Visibility—

Dew point45°

Fri, 2363° / 55°

63 °

Alto, Friday, 23 October

Clear. High 63°, low 55°.

Pressure30.06 inHg

Wind6.7 mph NE

Humidity38%

Visibility—

Dew point33°

Sat, 2468° / 56°

68 °

Alto, Saturday, 24 October

Clear. High 68°, low 56°.

Pressure30.09 inHg

Wind9.2 mph NE

Humidity30%

Visibility—

Dew point28°

From day 17 onward the outlook is built from 60-year climate statistics

Sun, 2568° / 53°

0.08

68 °

Alto, Sunday, 25 October

Climate normal for this date — 60-year average.

Average high68°

Average low53°

Average precipitation0.08 in

Chance of precipitation17%

Record high86° (2003)

Record low45° (2006)

Mon, 2668° / 51°

0.05

68 °

Alto, Monday, 26 October

Climate normal for this date — 60-year average.

Average high68°

Average low51°

Average precipitation0.05 in

Chance of precipitation12%

Record high86° (2003)

Record low45° (2022)

Tue, 2767° / 51°

0.03

67 °

Alto, Tuesday, 27 October

Climate normal for this date — 60-year average.

Average high67°

Average low51°

Average precipitation0.03 in

Chance of precipitation7%

Record high84° (2003)

Record low43° (2010)

Wed, 2866° / 51°

0.07

66 °

Alto, Wednesday, 28 October

Climate normal for this date — 60-year average.

Average high66°

Average low51°

Average precipitation0.07 in

Chance of precipitation17%

Record high82° (2003)

Record low43° (2023)

Thu, 2966° / 51°

0.06

66 °

Alto, Thursday, 29 October

Climate normal for this date — 60-year average.

Average high66°

Average low51°

Average precipitation0.06 in

Chance of precipitation22%

Record high78° (1965)

Record low43° (1971)

Fri, 3066° / 51°

0.06

66 °

Alto, Friday, 30 October

Climate normal for this date — 60-year average.

Average high66°

Average low51°

Average precipitation0.06 in

Chance of precipitation17%

Record high80° (1966)

Record low42° (1971)

Sat, 3167° / 50°

0.03

67 °

Alto, Saturday, 31 October

Climate normal for this date — 60-year average.

Average high67°

Average low50°

Average precipitation0.03 in

Chance of precipitation17%

Record high81° (1966)

Record low41° (1989)

Sun, 0167° / 50°

0.06

67 °

Alto, Sunday, 1 November

Climate normal for this date — 60-year average.

Average high67°

Average low50°

Average precipitation0.06 in

Chance of precipitation15%

Record high81° (1966)

Record low41° (1984)

Mon, 0267° / 50°

0.04

67 °

Alto, Monday, 2 November

Climate normal for this date — 60-year average.

Average high67°

Average low50°

Average precipitation0.04 in

Chance of precipitation13%

Record high80° (1997)

Record low42° (1974)

Tue, 0366° / 50°

0.03

66 °

Alto, Tuesday, 3 November

Climate normal for this date — 60-year average.

Average high66°

Average low50°

Average precipitation0.03 in

Chance of precipitation12%

Record high80° (1976)

Record low43° (1971)

Wed, 0466° / 50°

0.03

66 °

Alto, Wednesday, 4 November

Climate normal for this date — 60-year average.

Average high66°

Average low50°

Average precipitation0.03 in

Chance of precipitation10%

Record high80° (1976)

Record low42° (2003)

Thu, 0564° / 50°

0.06

64 °

Alto, Thursday, 5 November

Climate normal for this date — 60-year average.

Average high64°

Average low50°

Average precipitation0.06 in

Chance of precipitation15%

Record high77° (2020)

Record low44° (1971)

Fri, 0664° / 51°

0.07

64 °

Alto, Friday, 6 November

Climate normal for this date — 60-year average.

Average high64°

Average low51°

Average precipitation0.07 in

Chance of precipitation20%

Record high77° (1976)

Record low42° (1996)

Sat, 0764° / 50°

0.09

64 °

Alto, Saturday, 7 November

Climate normal for this date — 60-year average.

Average high64°

Average low50°

Average precipitation0.09 in

Chance of precipitation25%

Record high79° (1991)

Record low42° (1971)

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 Alto, 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 Alto, 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.