Monthly outlook for Acton, MA: average high 63.1°, average low 43.8°. That is 1.5° above the climate normal for October. Precipitation is expected on 2 days (about 0.5 inches), against a normal of 4 days and 1.9 inches. The warmest day looks like 16 October (70.3°), the coolest 19 October (29.8°).
63.1°/43.8°
Average high / low
+1.5°
Above normal
2 / 4
Wet days / normal
0.5 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
8 October – 17 October
65.2°
61.3°
+2.2°
18 October – 27 October
59.6°
57.9°
+1°
28 October – 6 November
at normal
54.5°
—
October records over 66 years
85.8°5 October 2007All-time high
23.4°31 October 2020All-time low
Climate normals and records are computed from the nearest reference point — Groton (11 mi).
Fri, 0968° / 49°0
68 °
Acton, Friday, 9 October
Clear. High 68°, low 49°.
Pressure30.03 inHg
Wind13.5 mph W
Humidity45%
Visibility6.2 mi
Dew point42°
Sat, 1062° / 46°0
62 °
Acton, Saturday, 10 October
Overcast. High 62°, low 46°.
Pressure30.45 inHg
Wind5.5 mph NW
Humidity39%
Visibility6.2 mi
Dew point33°
Sun, 1163° / 42°0.05
63 °
Acton, Sunday, 11 October
Light rain. High 63°, low 42°.
Pressure30.39 inHg
Wind6.4 mph S
Humidity60%
Visibility6.2 mi
Dew point48°
Mon, 1267° / 51°0.39
67 °
Acton, Monday, 12 October
Rain. High 67°, low 51°.
Pressure29.77 inHg
Wind6.6 mph N
Humidity78%
Visibility6.2 mi
Dew point55°
Tue, 1369° / 50°0.01
69 °
Acton, Tuesday, 13 October
Light rain. High 69°, low 50°.
Pressure29.65 inHg
Wind14 mph NW
Humidity81%
Visibility—
Dew point56°
Wed, 1458° / 43°0
58 °
Acton, Wednesday, 14 October
Mostly clear. High 58°, low 43°.
Pressure29.94 inHg
Wind14.2 mph NW
Humidity48%
Visibility—
Dew point32°
Thu, 1562° / 40°0
62 °
Acton, Thursday, 15 October
Partly cloudy. High 62°, low 40°.
Pressure30.30 inHg
Wind7.1 mph SW
Humidity51%
Visibility—
Dew point36°
Fri, 1670° / 53°0
70 °
Acton, Friday, 16 October
Mostly clear. High 70°, low 53°.
Pressure30.00 inHg
Wind12.2 mph W
Humidity67%
Visibility—
Dew point56°
Sat, 1763° / 38°0
63 °
Acton, Saturday, 17 October
Overcast. High 63°, low 38°.
Pressure29.94 inHg
Wind14.3 mph W
Humidity45%
Visibility—
Dew point32°
Sun, 1846° / 33°0
46 °
Acton, Sunday, 18 October
Clear. High 46°, low 33°.
Pressure30.27 inHg
Wind13.8 mph NW
Humidity39%
Visibility—
Dew point18°
Mon, 1953° / 30°0
53 °
Acton, Monday, 19 October
Clear. High 53°, low 30°.
Pressure30.53 inHg
Wind6.5 mph W
Humidity32%
Visibility—
Dew point16°
Tue, 2064° / 38°0
64 °
Acton, Tuesday, 20 October
Clear. High 64°, low 38°.
Pressure30.33 inHg
Wind6.5 mph W
Humidity43%
Visibility—
Dew point32°
Wed, 2163° / 41°0
63 °
Acton, Wednesday, 21 October
Partly cloudy. High 63°, low 41°.
Pressure30.45 inHg
Wind7.9 mph E
Humidity58%
Visibility—
Dew point41°
Thu, 2266° / 47°0
66 °
Acton, Thursday, 22 October
Overcast. High 66°, low 47°.
Pressure30.27 inHg
Wind10.7 mph SW
Humidity77%
Visibility—
Dew point50°
Fri, 2366° / 48°0
66 °
Acton, Friday, 23 October
Partly cloudy. High 66°, low 48°.
Pressure30.03 inHg
Wind8.4 mph NW
Humidity55%
Visibility—
Dew point44°
From day 17 onward the outlook is built from 60-year climate statistics
Sat, 2458° / 42°0.15
58 °
Acton, Saturday, 24 October
Climate normal for this date — 60-year average.
Average high58°
Average low42°
Average precipitation0.15 in
Chance of precipitation28%
Record high77° (1963)
Record low26° (1969)
Sun, 2557° / 43°0.14
57 °
Acton, Sunday, 25 October
Climate normal for this date — 60-year average.
Average high57°
Average low43°
Average precipitation0.14 in
Chance of precipitation35%
Record high80° (1963)
Record low30° (1982)
Mon, 2656° / 42°0.13
56 °
Acton, Monday, 26 October
Climate normal for this date — 60-year average.
Average high56°
Average low42°
Average precipitation0.13 in
Chance of precipitation30%
Record high80° (1963)
Record low29° (2018)
Tue, 2756° / 42°0.12
56 °
Acton, Tuesday, 27 October
Climate normal for this date — 60-year average.
Average high56°
Average low42°
Average precipitation0.12 in
Chance of precipitation22%
Record high80° (1963)
Record low28° (1976)
Wed, 2856° / 40°0.12
56 °
Acton, Wednesday, 28 October
Climate normal for this date — 60-year average.
Average high56°
Average low40°
Average precipitation0.12 in
Chance of precipitation35%
Record high78° (2023)
Record low27° (1976)
Thu, 2954° / 40°0.15
54 °
Acton, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high54°
Average low40°
Average precipitation0.15 in
Chance of precipitation28%
Record high71° (1989)
Record low29° (1965)
Fri, 3054° / 39°0.16
54 °
Acton, Friday, 30 October
Climate normal for this date — 60-year average.
Average high54°
Average low39°
Average precipitation0.16 in
Chance of precipitation28%
Record high71° (1989)
Record low24° (2020)
Sat, 3155° / 39°0.09
55 °
Acton, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high55°
Average low39°
Average precipitation0.09 in
Chance of precipitation22%
Record high77° (2024)
Record low23° (2020)
Sun, 0156° / 40°0.12
56 °
Acton, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high56°
Average low40°
Average precipitation0.12 in
Chance of precipitation30%
Record high75° (2024)
Record low29° (2011)
Mon, 0255° / 40°0.09
55 °
Acton, Monday, 2 November
Climate normal for this date — 60-year average.
Average high55°
Average low40°
Average precipitation0.09 in
Chance of precipitation28%
Record high74° (1982)
Record low26° (2011)
Tue, 0355° / 40°0.17
55 °
Acton, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high55°
Average low40°
Average precipitation0.17 in
Chance of precipitation37%
Record high72° (2017)
Record low25° (2002)
Wed, 0454° / 39°0.04
54 °
Acton, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high54°
Average low39°
Average precipitation0.04 in
Chance of precipitation22%
Record high73° (1987)
Record low27° (2002)
Thu, 0554° / 39°0.15
54 °
Acton, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high54°
Average low39°
Average precipitation0.15 in
Chance of precipitation32%
Record high75° (2022)
Record low28° (1965)
Fri, 0652° / 40°0.13
52 °
Acton, Friday, 6 November
Climate normal for this date — 60-year average.
Average high52°
Average low40°
Average precipitation0.13 in
Chance of precipitation35%
Record high76° (2024)
Record low27° (2012)
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 Acton, MA 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 Acton, MA 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.