Monthly outlook for Old Lyme, CT: average high 58°, average low 43.6°. That is 0.2° below the climate normal for October. Precipitation is expected on 3 days (about 0.4 inches), against a normal of 4 days and 2.1 inches. The warmest day looks like 20 October (63.4°), the coolest 18 October (34.7°).
58°/43.6°
Average high / low
−0.2°
Below normal
3 / 4
Wet days / normal
0.4 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
17 October – 26 October
59.4°
59.3°
+0.1°
27 October – 5 November
55.6°
56.7°
-0.6°
6 November – 15 November
at normal
52.6°
—
October records over 66 years
80.6°2 October 2019All-time high
29.1°31 October 2020All-time low
Sun, 1857° / 35°0
57 °
Old Lyme, Sunday, 18 October
Clear. High 57°, low 35°.
Pressure30.56 inHg
Wind4.2 mph NE
Humidity42%
Visibility6.2 mi
Dew point28°
Mon, 1962° / 40°0
62 °
Old Lyme, Monday, 19 October
Overcast. High 62°, low 40°.
Pressure30.42 inHg
Wind7.6 mph NE
Humidity41%
Visibility6.2 mi
Dew point35°
Tue, 2063° / 48°0
63 °
Old Lyme, Tuesday, 20 October
Overcast. High 63°, low 48°.
Pressure30.21 inHg
Wind14 mph N
Humidity51%
Visibility6.2 mi
Dew point43°
Wed, 2157° / 44°0
57 °
Old Lyme, Wednesday, 21 October
Partly cloudy. High 57°, low 44°.
Pressure30.30 inHg
Wind14.6 mph NE
Humidity63%
Visibility—
Dew point39°
Thu, 2262° / 43°0
62 °
Old Lyme, Thursday, 22 October
Mostly clear. High 62°, low 43°.
Pressure30.06 inHg
Wind11.3 mph N
Humidity53%
Visibility—
Dew point37°
Fri, 2358° / 47°0
58 °
Old Lyme, Friday, 23 October
Clear. High 58°, low 47°.
Pressure30.18 inHg
Wind15.9 mph NE
Humidity59%
Visibility—
Dew point39°
Sat, 2457° / 44°0
57 °
Old Lyme, Saturday, 24 October
Clear. High 57°, low 44°.
Pressure30.39 inHg
Wind16.5 mph NE
Humidity61%
Visibility—
Dew point39°
Sun, 2559° / 42°0
59 °
Old Lyme, Sunday, 25 October
Partly cloudy. High 59°, low 42°.
Pressure30.21 inHg
Wind12.9 mph N
Humidity41%
Visibility—
Dew point29°
Mon, 2660° / 49°0
60 °
Old Lyme, Monday, 26 October
Overcast. High 60°, low 49°.
Pressure30.09 inHg
Wind11.3 mph SW
Humidity55%
Visibility—
Dew point40°
Tue, 2762° / 46°0.02
62 °
Old Lyme, Tuesday, 27 October
Light rain. High 62°, low 46°.
Pressure29.88 inHg
Wind25.9 mph NW
Humidity71%
Visibility—
Dew point52°
Wed, 2851° / 39°0
51 °
Old Lyme, Wednesday, 28 October
Clear. High 51°, low 39°.
Pressure30.36 inHg
Wind20.3 mph NW
Humidity46%
Visibility—
Dew point26°
Thu, 2956° / 46°0.24
56 °
Old Lyme, Thursday, 29 October
Rain. High 56°, low 46°.
Pressure30.12 inHg
Wind20.2 mph S
Humidity49%
Visibility—
Dew point34°
Fri, 3053° / 46°0.04
53 °
Old Lyme, Friday, 30 October
Light rain. High 53°, low 46°.
Pressure29.68 inHg
Wind23.1 mph NW
Humidity77%
Visibility—
Dew point46°
Sat, 3153° / 43°0
53 °
Old Lyme, Saturday, 31 October
Mostly clear. High 53°, low 43°.
Pressure30.21 inHg
Wind12.8 mph N
Humidity60%
Visibility—
Dew point35°
Sun, 0158° / 49°0
58 °
Old Lyme, Sunday, 1 November
Overcast. High 58°, low 49°.
Pressure30.33 inHg
Wind12.5 mph S
Humidity69%
Visibility—
Dew point45°
From day 17 onward the outlook is built from 60-year climate statistics
Mon, 0257° / 47°0.08
57 °
Old Lyme, Monday, 2 November
Climate normal for this date — 60-year average.
Average high57°
Average low47°
Average precipitation0.08 in
Chance of precipitation30%
Record high69° (2022)
Record low31° (1965)
Tue, 0357° / 46°0.16
57 °
Old Lyme, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high57°
Average low46°
Average precipitation0.16 in
Chance of precipitation30%
Record high69° (2017)
Record low35° (1980)
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)
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.