December is one of the cooler months of the year in Ithaca, with average highs near 0.5°C and lows around -6.2°C (mean -2.8°C). It is about average for rainfall, averaging 78 mm of rainfall and 90% relative humidity across the period.
December is one of the cooler months of the year in Ithaca. Across 45 years of records, the warmest December in Ithaca was 2015 — when the month averaged 3.6°C — while the coldest was 1989 at -9.6°C. Typical December days reach 0.5°C with nights near -6.2°C. The long-term trend is warming, about 0.4°C per decade.
December is about average for rainfall in Ithaca, averaging 78 mm of rainfall. The wettest December on record was 2023 with 149 mm, while the driest was 1988 at 34 mm.
Relative humidity in Ithaca during December averages 90%. The most humid December was 2007 at 95%, and the least humid were 1988 and 1998 at 83%.
December receives about 1.1 kWh/m²/day of solar energy in Ithaca. The sunniest Decembers were 2000, 2001 and 2011, among others at 1.4 kWh/m²/day, and the cloudiest were 2007 and 2013 at 0.9.
Average wind speed in Ithaca during December is 0.6 m/s. The windiest Decembers were 2008 and 2025 at 0.7 m/s, while the calmest were 2018, 2021 and 2023, among others at 0.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | -4.0°C | -2.4°C | -3.3°C | -2.2°C | -2.1°C | +1.9°C |
| Avg High | -0.7°C | 1.1°C | 0.0°C | 1.0°C | 1.3°C | +2°C |
| Avg Low | -7.4°C | -5.9°C | -6.6°C | -5.3°C | -5.5°C | +1.9°C |
| Avg Rain | 65 mm | 74 mm | 79 mm | 80 mm | 95 mm | +30 mm |
December temperatures in Ithaca have risen by about 1.7°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -21.1°C (1983) to a record high of 18.8°C (2006).
Rainfall in December is about average for rainfall, averaging 78 mm, with a wettest year of 149 mm.
A quieter season to visit Ithaca
If your dates are flexible, the more temperate months of July and August tend to be the most comfortable for visiting Ithaca. That said, December — with days averaging 0.5°C and nights around -6.2°C (mean -2.8°C) and moderate rainfall (78 mm) — can still be rewarding for travellers who don't mind the cooler conditions, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | -1.6°C | -5.6°C | -9.6°C | 9.6°C | -17.3°C | 77 mm | 89% | 0.7 m/s | — |
| 2024 | 0.3°C | -2.9°C | -6.1°C | 10.4°C | -16.2°C | 83 mm | 91% | 0.6 m/s | 1.1 |
| 2023 🌧️ | 4.0°C | 0.8°C | -2.3°C | 8.9°C | -10.0°C | 149 mm | 93% | 0.5 m/s | 1.1 |
| 2022 | 0.8°C | -2.9°C | -6.6°C | 10.4°C | -18.3°C | 88 mm | 91% | 0.6 m/s | 1.2 |
| 2021 | 3.4°C | 0.4°C | -2.7°C | 13.6°C | -8.6°C | 69 mm | 90% | 0.5 m/s | 1.2 |
| 2020 | 1.0°C | -2.2°C | -5.5°C | 11.8°C | -17.9°C | 104 mm | 90% | 0.6 m/s | 1 |
| 2019 | 0.2°C | -3.1°C | -6.5°C | 5.4°C | -15.1°C | 92 mm | 93% | 0.6 m/s | 1.1 |
| 2018 | 1.3°C | -1.8°C | -4.9°C | 12.8°C | -9.7°C | 79 mm | 93% | 0.5 m/s | 1 |
| 2017 | -1.7°C | -4.5°C | -7.3°C | 9.0°C | -18.2°C | 39 mm | 86% | 0.6 m/s | 1.2 |
| 2016 | 0.1°C | -3.2°C | -6.5°C | 7.8°C | -14.6°C | 65 mm | 90% | 0.6 m/s | 1.1 |
| 2015 🔥 | 7.3°C | 3.6°C | -0.1°C | 17.0°C | -5.2°C | 90 mm | 89% | 0.6 m/s | 1.2 |
| 2014 | 0.7°C | -2.2°C | -5.1°C | 8.5°C | -12.3°C | 72 mm | 91% | 0.5 m/s | 1 |
| 2013 | -0.6°C | -3.7°C | -6.7°C | 14.8°C | -18.4°C | 78 mm | 92% | 0.5 m/s | 0.9 |
| 2012 | 2.3°C | -0.8°C | -3.9°C | 17.3°C | -18.1°C | 145 mm | 94% | 0.6 m/s | 1.2 |
| 2011 | 2.9°C | -0.6°C | -4.1°C | 8.8°C | -13.3°C | 75 mm | 91% | 0.6 m/s | 1.4 |
| 2010 | -2.5°C | -5.3°C | -8.0°C | 13.1°C | -13.8°C | 63 mm | 92% | 0.6 m/s | 1.1 |
| 2009 | -0.8°C | -3.7°C | -6.5°C | 10.4°C | -14.7°C | 60 mm | 88% | 0.6 m/s | 1.1 |
| 2008 | -0.6°C | -4.2°C | -7.8°C | 9.8°C | -16.9°C | 108 mm | 90% | 0.7 m/s | 1.1 |
| 2007 | -1.0°C | -4.3°C | -7.5°C | 6.5°C | -17.7°C | 122 mm | 95% | 0.6 m/s | 0.9 |
| 2006 | 4.1°C | 0.5°C | -3.0°C | 18.8°C | -12.6°C | 63 mm | 90% | 0.6 m/s | 1.3 |
| 2005 | -2.3°C | -5.2°C | -8.2°C | 3.4°C | -17.7°C | 63 mm | 94% | 0.5 m/s | 1.1 |
| 2004 | 0.2°C | -3.4°C | -7.0°C | 10.4°C | -18.7°C | 96 mm | 91% | 0.6 m/s | 1 |
| 2003 | 0.3°C | -3.0°C | -6.3°C | 6.9°C | -13.4°C | 92 mm | 91% | 0.6 m/s | 1.2 |
| 2002 | -1.3°C | -4.5°C | -7.8°C | 5.0°C | -19.0°C | 83 mm | 93% | 0.6 m/s | 1.1 |
| 2001 | 3.8°C | 0.4°C | -3.1°C | 17.9°C | -10.0°C | 51 mm | 86% | 0.6 m/s | 1.4 |
| 2000 | -2.8°C | -6.0°C | -9.2°C | 10.8°C | -13.9°C | 57 mm | 86% | 0.6 m/s | 1.4 |
| 1999 | 1.6°C | -1.9°C | -5.4°C | 15.2°C | -14.7°C | 42 mm | 86% | 0.6 m/s | 1.1 |
| 1998 | 4.9°C | 0.4°C | -4.1°C | 17.5°C | -13.0°C | 41 mm | 83% | 0.6 m/s | 1.2 |
| 1997 | 0.3°C | -2.9°C | -6.0°C | 4.9°C | -15.5°C | 78 mm | 92% | 0.5 m/s | 1.2 |
| 1996 | 1.3°C | -1.3°C | -3.9°C | 10.1°C | -15.0°C | 124 mm | 93% | 0.6 m/s | 1 |
| 1995 | -3.4°C | -6.2°C | -9.0°C | 5.8°C | -14.5°C | 48 mm | 91% | 0.6 m/s | 1.4 |
| 1994 | 2.4°C | -1.6°C | -5.5°C | 11.7°C | -16.5°C | 65 mm | 90% | 0.6 m/s | 1.1 |
| 1993 | -0.8°C | -4.4°C | -8.1°C | 5.1°C | -20.9°C | 72 mm | 92% | 0.6 m/s | 1.1 |
| 1992 | 0.7°C | -2.6°C | -5.8°C | 8.7°C | -12.8°C | 70 mm | 89% | 0.6 m/s | 1.1 |
| 1991 | 1.2°C | -2.4°C | -6.1°C | 10.5°C | -13.9°C | 73 mm | 87% | 0.6 m/s | 1.2 |
| 1990 | 2.4°C | -1.3°C | -5.0°C | 10.7°C | -14.9°C | 132 mm | 89% | 0.6 m/s | 1 |
| 1989 ❄️ | -6.2°C | -9.6°C | -13.1°C | 0.7°C | -18.0°C | 39 mm | 89% | 0.6 m/s | 1.4 |
| 1988 | -0.4°C | -3.9°C | -7.5°C | 7.8°C | -17.6°C | 34 mm | 83% | 0.6 m/s | 1.2 |
| 1987 | 1.1°C | -2.0°C | -5.1°C | 6.9°C | -16.1°C | 53 mm | 89% | 0.6 m/s | 1.1 |
| 1986 | 0.9°C | -2.4°C | -5.7°C | 4.3°C | -13.2°C | 67 mm | 90% | 0.5 m/s | 1.2 |
| 1985 | -2.5°C | -6.1°C | -9.7°C | 6.4°C | -16.8°C | 54 mm | 92% | 0.6 m/s | 1.1 |
| 1984 | 2.2°C | -1.2°C | -4.6°C | 16.5°C | -11.6°C | 87 mm | 91% | 0.6 m/s | 1.1 |
| 1983 | -3.1°C | -6.1°C | -9.2°C | 5.0°C | -21.1°C | 145 mm | 89% | 0.6 m/s | — |
| 1982 | 3.7°C | -0.3°C | -4.2°C | 15.6°C | -13.6°C | 50 mm | 86% | 0.6 m/s | — |
| 1981 | -1.8°C | -4.8°C | -7.7°C | 4.6°C | -15.5°C | 56 mm | 94% | 0.6 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 0.5°C with lows near -6.2°C (mean -2.8°C), based on 45 years of NASA POWER data.
December averages 78 mm of rainfall in Ithaca, about average for rainfall. The wettest on record was 149 mm in 2023.
The hottest December reached 18.8°C in 2006. The coldest dipped to -21.1°C in 1983.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 1.7°C. Daytime highs moved from -0.3°C to 1.4°C and overnight lows from -7.1°C to -5.5°C over the same span.
December is one of the cooler months of the year in Ithaca and about average for rainfall, so plan for around 0.5°C daytime highs and -6.2°C at night.
Not quite — December is the 3rd coolest month in Ithaca, averaging -2.8°C.
For December in Ithaca, pack warm layers and a jacket for chilly mornings, with typical highs of 0.5°C and lows of -6.2°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 90% — quite humid.
Average wind speed in December is 0.6 m/s. The windiest December on record averaged 0.7 m/s (2008).
The wettest December on record was 2023 with 149 mm. On average, December sees 78 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Ithaca behaves each December, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for December specifically, along with year-by-year records and how the month has changed over the decades.
