Monthly outlook for Grass Valley, MT: average high 57.9°, average low 35.5°. That is 6.4° above the climate normal for October. Precipitation is expected on 1 day (about 0.1 inches), against a normal of 6 days and 1.1 inches. The warmest day looks like 17 October (67.4°), the coolest 25 October (30.3°).
57.9°/35.5°
Average high / low
+6.4°
Above normal
1 / 6
Wet days / normal
0.1 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
17 October – 26 October
59°
48.7°
+5.7°
27 October – 5 November
56.1°
42°
+7.8°
6 November – 15 November
at normal
37.5°
—
October records over 66 years
78.4°1 October 1992All-time high
-12.5°29 October 2019All-time low
Climate normals and records are computed from the nearest reference point — Evaro (11 mi).
Sun, 1859° / 33°0
59 °
Grass Valley, Sunday, 18 October
Clear. High 59°, low 33°.
Pressure30.12 inHg
Wind1.1 mph SE
Humidity65%
Visibility6.2 mi
Dew point39°
Mon, 1963° / 39°0
63 °
Grass Valley, Monday, 19 October
Overcast. High 63°, low 39°.
Pressure29.88 inHg
Wind1.9 mph S
Humidity56%
Visibility6.2 mi
Dew point38°
Tue, 2061° / 38°0
61 °
Grass Valley, Tuesday, 20 October
Overcast. High 61°, low 38°.
Pressure30.03 inHg
Wind1.1 mph S
Humidity62%
Visibility6.2 mi
Dew point41°
Wed, 2161° / 39°0
61 °
Grass Valley, Wednesday, 21 October
Clear. High 61°, low 39°.
Pressure30.09 inHg
Wind1.4 mph S
Humidity59%
Visibility—
Dew point38°
Thu, 2263° / 43°0.01
63 °
Grass Valley, Thursday, 22 October
Light rain. High 63°, low 43°.
Pressure29.91 inHg
Wind5.4 mph SE
Humidity51%
Visibility—
Dew point37°
Fri, 2348° / 40°0.11
48 °
Grass Valley, Friday, 23 October
Light rain. High 48°, low 40°.
Pressure30.15 inHg
Wind5.3 mph NE
Humidity93%
Visibility—
Dew point41°
Sat, 2454° / 32°0
54 °
Grass Valley, Saturday, 24 October
Clear. High 54°, low 32°.
Pressure30.36 inHg
Wind9.2 mph E
Humidity41%
Visibility—
Dew point22°
Sun, 2554° / 30°0
54 °
Grass Valley, Sunday, 25 October
Mostly clear. High 54°, low 30°.
Pressure30.15 inHg
Wind3.7 mph SE
Humidity37%
Visibility—
Dew point19°
Mon, 2659° / 35°0
59 °
Grass Valley, Monday, 26 October
Partly cloudy. High 59°, low 35°.
Pressure30.18 inHg
Wind5.4 mph W
Humidity45%
Visibility—
Dew point29°
Tue, 2761° / 36°0
61 °
Grass Valley, Tuesday, 27 October
Mostly clear. High 61°, low 36°.
Pressure30.12 inHg
Wind2.6 mph SE
Humidity43%
Visibility—
Dew point29°
Wed, 2858° / 37°0
58 °
Grass Valley, Wednesday, 28 October
Partly cloudy. High 58°, low 37°.
Pressure29.94 inHg
Wind5.4 mph E
Humidity41%
Visibility—
Dew point28°
Thu, 2949° / 36°0
49 °
Grass Valley, Thursday, 29 October
Overcast. High 49°, low 36°.
Pressure29.94 inHg
Wind4.7 mph E
Humidity54%
Visibility—
Dew point29°
Fri, 3057° / 32°0
57 °
Grass Valley, Friday, 30 October
Clear. High 57°, low 32°.
Pressure30.18 inHg
Wind1.9 mph SE
Humidity48%
Visibility—
Dew point28°
Sat, 3159° / 32°0
59 °
Grass Valley, Saturday, 31 October
Clear. High 59°, low 32°.
Pressure30.24 inHg
Wind2.3 mph W
Humidity35%
Visibility—
Dew point22°
Sun, 0152° / 35°0
52 °
Grass Valley, Sunday, 1 November
Clear. High 52°, low 35°.
Pressure30.06 inHg
Wind3.3 mph SE
Humidity38%
Visibility—
Dew point25°
From day 17 onward the outlook is built from 60-year climate statistics
Mon, 0241° / 27°0.1
41 °
Grass Valley, Monday, 2 November
Climate normal for this date — 60-year average.
Average high41°
Average low27°
Average precipitation0.1 in
Chance of precipitation33%
Record high58° (1981)
Record low-1° (1991)
Tue, 0341° / 27°0.05
41 °
Grass Valley, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high41°
Average low27°
Average precipitation0.05 in
Chance of precipitation32%
Record high58° (1981)
Record low-7° (1973)
Wed, 0441° / 28°0.1
41 °
Grass Valley, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high41°
Average low28°
Average precipitation0.1 in
Chance of precipitation52%
Record high56° (1980)
Record low-7° (1973)
Thu, 0540° / 27°0.09
40 °
Grass Valley, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high40°
Average low27°
Average precipitation0.09 in
Chance of precipitation45%
Record high58° (1980)
Record low-8° (2003)
Fri, 0640° / 25°0.1
40 °
Grass Valley, Friday, 6 November
Climate normal for this date — 60-year average.
Average high40°
Average low25°
Average precipitation0.1 in
Chance of precipitation47%
Record high58° (2012)
Record low-1° (2003)
Sat, 0739° / 25°0.11
39 °
Grass Valley, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high39°
Average low25°
Average precipitation0.11 in
Chance of precipitation50%
Record high53° (1978)
Record low2° (2003)
Sun, 0838° / 24°0.07
38 °
Grass Valley, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high38°
Average low24°
Average precipitation0.07 in
Chance of precipitation43%
Record high56° (2016)
Record low-1° (1994)
Mon, 0938° / 24°0.07
38 °
Grass Valley, Monday, 9 November
Climate normal for this date — 60-year average.
Average high38°
Average low24°
Average precipitation0.07 in
Chance of precipitation42%
Record high58° (2016)
Record low1° (2020)
Tue, 1037° / 23°0.06
37 °
Grass Valley, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high37°
Average low23°
Average precipitation0.06 in
Chance of precipitation40%
Record high55° (2016)
Record low-19° (1986)
Wed, 1137° / 21°0.07
37 °
Grass Valley, Wednesday, 11 November
Climate normal for this date — 60-year average.
Average high37°
Average low21°
Average precipitation0.07 in
Chance of precipitation35%
Record high56° (2016)
Record low-7° (2000)
Thu, 1237° / 23°0.08
37 °
Grass Valley, Thursday, 12 November
Climate normal for this date — 60-year average.
Average high37°
Average low23°
Average precipitation0.08 in
Chance of precipitation43%
Record high58° (1999)
Record low-9° (1986)
Fri, 1337° / 24°0.09
37 °
Grass Valley, Friday, 13 November
Climate normal for this date — 60-year average.
Average high37°
Average low24°
Average precipitation0.09 in
Chance of precipitation45%
Record high55° (2025)
Record low1° (2000)
Sat, 1437° / 23°0.08
37 °
Grass Valley, Saturday, 14 November
Climate normal for this date — 60-year average.
Average high37°
Average low23°
Average precipitation0.08 in
Chance of precipitation40%
Record high54° (1999)
Record low-2° (2000)
Sun, 1537° / 22°0.03
37 °
Grass Valley, Sunday, 15 November
Climate normal for this date — 60-year average.
Average high37°
Average low22°
Average precipitation0.03 in
Chance of precipitation17%
Record high54° (2021)
Record low0° (2014)
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 Grass Valley, MT 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 Grass Valley, MT 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.