Monthly outlook for Old Lyme, CT: average high 56.2°, average low 41.8°. That is 1° below the climate normal for October. Precipitation is expected on 0 days (about 0.0 inches), against a normal of 4 days and 2.1 inches. The warmest day looks like 20 October (65.4°), the coolest 31 October (35.1°).
56.2°/41.8°
Average high / low
−1°
Below normal
0 / 4
Wet days / normal
0.0 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
19 October – 28 October
59.2°
58.9°
+0.2°
29 October – 7 November
51.2°
56°
-2.7°
8 November – 17 November
at normal
51.8°
—
October records over 66 years
80.6°2 October 2019All-time high
29.1°31 October 2020All-time low
Tue, 2065° / 41°0
65 °
Old Lyme, Tuesday, 20 October
Clear. High 65°, low 41°.
Pressure30.18 inHg
Wind13.6 mph NE
Humidity46%
Visibility6.2 mi
Dew point42°
Wed, 2157° / 42°0
57 °
Old Lyme, Wednesday, 21 October
Partly cloudy. High 57°, low 42°.
Pressure30.21 inHg
Wind10.3 mph NE
Humidity57%
Visibility6.2 mi
Dew point39°
Thu, 2262° / 40°0
62 °
Old Lyme, Thursday, 22 October
Clear. High 62°, low 40°.
Pressure29.94 inHg
Wind9.6 mph NW
Humidity43%
Visibility6.2 mi
Dew point36°
Fri, 2352° / 39°0
52 °
Old Lyme, Friday, 23 October
Clear. High 52°, low 39°.
Pressure30.18 inHg
Wind12.1 mph NW
Humidity53%
Visibility—
Dew point31°
Sat, 2454° / 36°0
54 °
Old Lyme, Saturday, 24 October
Clear. High 54°, low 36°.
Pressure30.56 inHg
Wind7.4 mph N
Humidity50%
Visibility—
Dew point30°
Sun, 2556° / 46°0
56 °
Old Lyme, Sunday, 25 October
Clear. High 56°, low 46°.
Pressure30.56 inHg
Wind13.6 mph SW
Humidity55%
Visibility—
Dew point37°
Mon, 2660° / 54°0
60 °
Old Lyme, Monday, 26 October
Overcast. High 60°, low 54°.
Pressure30.30 inHg
Wind16.1 mph SW
Humidity73%
Visibility—
Dew point48°
Tue, 2760° / 53°0
60 °
Old Lyme, Tuesday, 27 October
Overcast. High 60°, low 53°.
Pressure30.18 inHg
Wind10 mph SW
Humidity59%
Visibility—
Dew point44°
Wed, 2863° / 48°0
63 °
Old Lyme, Wednesday, 28 October
Overcast. High 63°, low 48°.
Pressure29.94 inHg
Wind19.6 mph N
Humidity73%
Visibility—
Dew point53°
Thu, 2945° / 37°0
45 °
Old Lyme, Thursday, 29 October
Overcast. High 45°, low 37°.
Pressure30.30 inHg
Wind16.9 mph N
Humidity41%
Visibility—
Dew point18°
Fri, 3048° / 35°0
48 °
Old Lyme, Friday, 30 October
Clear. High 48°, low 35°.
Pressure30.33 inHg
Wind11.1 mph N
Humidity39%
Visibility—
Dew point20°
Sat, 3149° / 35°0
49 °
Old Lyme, Saturday, 31 October
Clear. High 49°, low 35°.
Pressure30.59 inHg
Wind14.2 mph N
Humidity41%
Visibility—
Dew point21°
Sun, 0153° / 37°0
53 °
Old Lyme, Sunday, 1 November
Clear. High 53°, low 37°.
Pressure30.56 inHg
Wind8.8 mph N
Humidity39%
Visibility—
Dew point22°
Mon, 0257° / 42°0
57 °
Old Lyme, Monday, 2 November
Partly cloudy. High 57°, low 42°.
Pressure30.45 inHg
Wind6.3 mph N
Humidity39%
Visibility—
Dew point26°
Tue, 0355° / 45°0
55 °
Old Lyme, Tuesday, 3 November
Clear. High 55°, low 45°.
Pressure30.36 inHg
Wind7.2 mph NE
Humidity40%
Visibility—
Dew point28°
From day 17 onward the outlook is built from 60-year climate statistics
Wed, 0456° / 46°0.04
56 °
Old Lyme, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high56°
Average low46°
Average precipitation0.04 in
Chance of precipitation27%
Record high68° (1975)
Record low34° (2013)
Thu, 0556° / 46°0.15
56 °
Old Lyme, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high56°
Average low46°
Average precipitation0.15 in
Chance of precipitation40%
Record high70° (2022)
Record low34° (1965)
Fri, 0655° / 45°0.11
55 °
Old Lyme, Friday, 6 November
Climate normal for this date — 60-year average.
Average high55°
Average low45°
Average precipitation0.11 in
Chance of precipitation35%
Record high71° (2024)
Record low33° (2012)
Sat, 0755° / 44°0.07
55 °
Old Lyme, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high55°
Average low44°
Average precipitation0.07 in
Chance of precipitation25%
Record high72° (2022)
Record low32° (1962)
Sun, 0853° / 43°0.13
53 °
Old Lyme, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high53°
Average low43°
Average precipitation0.13 in
Chance of precipitation32%
Record high71° (2020)
Record low30° (2019)
Mon, 0953° / 43°0.09
53 °
Old Lyme, Monday, 9 November
Climate normal for this date — 60-year average.
Average high53°
Average low43°
Average precipitation0.09 in
Chance of precipitation22%
Record high67° (1975)
Record low26° (2019)
Tue, 1054° / 43°0.18
54 °
Old Lyme, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high54°
Average low43°
Average precipitation0.18 in
Chance of precipitation40%
Record high65° (1999)
Record low27° (2017)
Wed, 1153° / 43°0.16
53 °
Old Lyme, Wednesday, 11 November
Climate normal for this date — 60-year average.
Average high53°
Average low43°
Average precipitation0.16 in
Chance of precipitation35%
Record high67° (2022)
Record low23° (2017)
Thu, 1252° / 41°0.16
52 °
Old Lyme, Thursday, 12 November
Climate normal for this date — 60-year average.
Average high52°
Average low41°
Average precipitation0.16 in
Chance of precipitation38%
Record high71° (2022)
Record low28° (2019)
Fri, 1351° / 40°0.21
51 °
Old Lyme, Friday, 13 November
Climate normal for this date — 60-year average.
Average high51°
Average low40°
Average precipitation0.21 in
Chance of precipitation40%
Record high65° (1964)
Record low22° (2019)
Sat, 1450° / 40°0.09
50 °
Old Lyme, Saturday, 14 November
Climate normal for this date — 60-year average.
Average high50°
Average low40°
Average precipitation0.09 in
Chance of precipitation22%
Record high62° (1989)
Record low25° (1986)
Sun, 1551° / 40°0.13
51 °
Old Lyme, Sunday, 15 November
Climate normal for this date — 60-year average.
Average high51°
Average low40°
Average precipitation0.13 in
Chance of precipitation42%
Record high67° (1993)
Record low24° (1967)
Mon, 1651° / 40°0.15
51 °
Old Lyme, Monday, 16 November
Climate normal for this date — 60-year average.
Average high51°
Average low40°
Average precipitation0.15 in
Chance of precipitation35%
Record high64° (2001)
Record low23° (1967)
Tue, 1750° / 40°0.15
50 °
Old Lyme, Tuesday, 17 November
Climate normal for this date — 60-year average.
Average high50°
Average low40°
Average precipitation0.15 in
Chance of precipitation28%
Record high65° (2024)
Record low26° (2019)
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 Old Lyme, CT 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 Old Lyme, CT 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.