January is one of the cooler months of the year in Waltham, with average highs near 0.2°C and lows around -7.9°C (mean -3.8°C). It is about average for rainfall, averaging 93 mm of rainfall and 88% relative humidity across the period.
January is one of the cooler months of the year in Waltham. Across 45 years of records, the warmest January in Waltham was 2023 — when the month averaged 0.4°C — while the coldest was 1982 at -9.5°C. Typical January days reach 0.2°C with nights near -7.9°C. The long-term trend is warming, about 0.7°C per decade.
January is about average for rainfall in Waltham, averaging 93 mm of rainfall. The wettest January on record was 2024 with 213 mm, while the driest was 1981 at 25 mm.
Relative humidity in Waltham during January averages 88%. The most humid January was 2003 at 96%, and the least humid was 2025 at 79%.
January receives about 1.8 kWh/m²/day of solar energy in Waltham. The sunniest Januarys were 2009, 2012 and 2025, among others at 2 kWh/m²/day, and the cloudiest were 1984 and 2023 at 1.5.
Average wind speed in Waltham during January is 1 m/s. The windiest Januarys were 2000, 2004 and 2025, among others at 1.2 m/s, while the calmest were 2001, 2002 and 2023, among others at 0.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | -5.7°C | -3.5°C | -4.1°C | -3.5°C | -2.1°C | +3.6°C |
| Avg High | -1.4°C | 0.6°C | -0.1°C | 0.6°C | 1.6°C | +3°C |
| Avg Low | -10.0°C | -7.5°C | -8.1°C | -7.5°C | -5.9°C | +4.1°C |
| Avg Rain | 84 mm | 114 mm | 78 mm | 88 mm | 102 mm | +18 mm |
January temperatures in Waltham have risen by about 4.5°C between 1981–1985 and 2021–2025.
January has ranged from a record low of -25.3°C (1994) to a record high of 18°C (2007).
Rainfall in January is about average for rainfall, averaging 93 mm, with a wettest year of 213 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.6°C per decade while lows rose 0.8°C per decade, narrowing the gap between day and night.
A quieter season to visit Waltham
If your dates are flexible, the more temperate months of July and August tend to be the most comfortable for visiting Waltham. That said, January — with days averaging 0.2°C and nights around -7.9°C (mean -3.8°C) and higher rainfall (93 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 | 0.0°C | -3.7°C | -7.4°C | 7.3°C | -15.7°C | 52 mm | 79% | 1.2 m/s | 2 |
| 2024 🌧️ | 1.7°C | -1.6°C | -4.9°C | 11.4°C | -11.9°C | 213 mm | 89% | 1 m/s | 1.6 |
| 2023 🔥 | 3.8°C | 0.4°C | -3.0°C | 12.1°C | -9.3°C | 171 mm | 91% | 0.9 m/s | 1.5 |
| 2022 | -0.4°C | -5.0°C | -9.6°C | 8.1°C | -17.5°C | 72 mm | 84% | 1.1 m/s | 1.9 |
| 2021 | 1.4°C | -2.3°C | -5.9°C | 8.3°C | -15.7°C | 59 mm | 86% | 1 m/s | 1.9 |
| 2020 | 3.4°C | -0.6°C | -4.6°C | 16.5°C | -13.4°C | 45 mm | 87% | 1 m/s | 1.9 |
| 2019 | 0.0°C | -4.2°C | -8.4°C | 12.2°C | -19.4°C | 138 mm | 87% | 1.1 m/s | 1.9 |
| 2018 | 0.0°C | -4.2°C | -8.3°C | 13.9°C | -22.7°C | 105 mm | 89% | 1.1 m/s | 1.8 |
| 2017 | 3.2°C | -0.3°C | -3.7°C | 13.7°C | -15.6°C | 106 mm | 86% | 1 m/s | 1.7 |
| 2016 | 2.0°C | -1.9°C | -5.8°C | 12.8°C | -15.6°C | 67 mm | 85% | 1.1 m/s | 1.9 |
| 2015 | -1.7°C | -6.0°C | -10.2°C | 6.5°C | -20.3°C | 104 mm | 89% | 1.1 m/s | 1.7 |
| 2014 | -0.3°C | -4.7°C | -9.1°C | 12.9°C | -23.5°C | 81 mm | 85% | 1.1 m/s | 1.8 |
| 2013 | 1.5°C | -2.6°C | -6.6°C | 14.9°C | -19.0°C | 38 mm | 84% | 1 m/s | 1.9 |
| 2012 | 3.0°C | -1.1°C | -5.2°C | 9.0°C | -14.7°C | 73 mm | 85% | 1 m/s | 2 |
| 2011 | -1.6°C | -5.7°C | -9.7°C | 8.9°C | -24.3°C | 85 mm | 92% | 1 m/s | 1.9 |
| 2010 | 0.0°C | -4.2°C | -8.4°C | 11.5°C | -16.6°C | 81 mm | 90% | 1.1 m/s | 1.9 |
| 2009 | -2.9°C | -7.5°C | -12.0°C | 1.6°C | -21.6°C | 90 mm | 94% | 1 m/s | 2 |
| 2008 | 2.3°C | -2.0°C | -6.3°C | 15.0°C | -16.5°C | 75 mm | 87% | 1 m/s | 1.8 |
| 2007 | 2.1°C | -1.7°C | -5.4°C | 18.0°C | -17.4°C | 74 mm | 85% | 1 m/s | 1.8 |
| 2006 | 3.7°C | -0.1°C | -3.8°C | 13.1°C | -13.1°C | 123 mm | 92% | 1 m/s | 1.6 |
| 2005 | -1.4°C | -5.3°C | -9.1°C | 12.2°C | -20.2°C | 101 mm | 91% | 1.1 m/s | 1.8 |
| 2004 | -4.5°C | -8.1°C | -11.7°C | 8.5°C | -22.2°C | 28 mm | 83% | 1.2 m/s | 1.8 |
| 2003 | -4.0°C | -8.1°C | -12.3°C | 2.6°C | -23.0°C | 64 mm | 96% | 1.1 m/s | 1.9 |
| 2002 | 3.9°C | 0.3°C | -3.3°C | 15.5°C | -8.2°C | 74 mm | 86% | 0.9 m/s | 1.7 |
| 2001 | 0.2°C | -4.0°C | -8.2°C | 5.1°C | -13.0°C | 59 mm | 92% | 0.9 m/s | 1.9 |
| 2000 | -0.6°C | -4.8°C | -9.1°C | 14.2°C | -18.2°C | 89 mm | 85% | 1.2 m/s | 1.7 |
| 1999 | 1.9°C | -2.6°C | -7.1°C | 14.9°C | -17.6°C | 161 mm | 84% | 1 m/s | 1.7 |
| 1998 | 2.3°C | -1.3°C | -4.9°C | 14.4°C | -17.0°C | 146 mm | 91% | 1 m/s | 1.6 |
| 1997 | 0.4°C | -3.6°C | -7.7°C | 9.7°C | -19.3°C | 88 mm | 85% | 1.1 m/s | 1.7 |
| 1996 | -1.2°C | -5.5°C | -9.7°C | 13.5°C | -21.9°C | 169 mm | 93% | 1.1 m/s | 1.6 |
| 1995 | 2.9°C | -0.6°C | -4.0°C | 15.8°C | -12.4°C | 106 mm | 88% | 0.9 m/s | 1.9 |
| 1994 | -4.2°C | -9.1°C | -14.0°C | 9.4°C | -25.3°C | 136 mm | 95% | 1 m/s | 1.7 |
| 1993 | 0.9°C | -3.1°C | -7.2°C | 13.0°C | -14.2°C | 63 mm | 86% | 1 m/s | 1.7 |
| 1992 | 0.5°C | -3.7°C | -7.9°C | 10.3°C | -16.7°C | 77 mm | 85% | 1 m/s | 1.8 |
| 1991 | -0.3°C | -4.5°C | -8.7°C | 6.6°C | -16.8°C | 84 mm | 87% | 1 m/s | 1.7 |
| 1990 | 3.1°C | -0.6°C | -4.3°C | 9.8°C | -11.2°C | 111 mm | 89% | 0.9 m/s | 1.7 |
| 1989 | 2.4°C | -1.9°C | -6.1°C | 8.5°C | -16.5°C | 26 mm | 83% | 1 m/s | 1.7 |
| 1988 | -1.5°C | -5.8°C | -10.1°C | 7.8°C | -20.6°C | 71 mm | 91% | 1 m/s | 1.8 |
| 1987 | -1.4°C | -5.7°C | -9.9°C | 4.9°C | -19.2°C | 158 mm | 95% | 1.1 m/s | 1.7 |
| 1986 | 0.9°C | -3.5°C | -7.9°C | 11.1°C | -21.0°C | 123 mm | 86% | 1.1 m/s | 1.9 |
| 1985 | -2.4°C | -6.3°C | -10.2°C | 7.7°C | -16.0°C | 31 mm | 84% | 1.1 m/s | 2 |
| 1984 | -2.4°C | -6.6°C | -10.9°C | 5.4°C | -24.7°C | 62 mm | 94% | 0.9 m/s | 1.5 |
| 1983 | 0.7°C | -3.1°C | -6.9°C | 11.6°C | -17.7°C | 129 mm | 86% | 1 m/s | — |
| 1982 ❄️ | -4.7°C | -9.5°C | -14.2°C | 7.4°C | -21.9°C | 130 mm | 94% | 1.2 m/s | — |
| 1981 | -4.6°C | -9.2°C | -13.8°C | 5.4°C | -21.3°C | 25 mm | 88% | 1 m/s | — |
Actual recorded January data for each year, 1981–2025 — sourced from NASA POWER.
The average high in January is around 0.2°C with lows near -7.9°C (mean -3.8°C), based on 45 years of NASA POWER data.
January averages 93 mm of rainfall in Waltham, about average for rainfall. The wettest on record was 213 mm in 2024.
The hottest January reached 18°C in 2007. The coldest dipped to -25.3°C in 1994.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average January temperatures have risen by about 4.5°C. Daytime highs moved from -2.7°C to 1.3°C and overnight lows from -11.2°C to -6.2°C over the same span.
January is one of the cooler months of the year in Waltham and about average for rainfall, so plan for around 0.2°C daytime highs and -7.9°C at night.
Yes — January is the coldest month of the year in Waltham, averaging -3.8°C.
For January in Waltham, pack warm layers and a jacket for chilly mornings, with typical highs of 0.2°C and lows of -7.9°C. Bring an umbrella or light rain jacket too.
Relative humidity in January averages 88% — quite humid.
Average wind speed in January is 1 m/s. The windiest January on record averaged 1.2 m/s (1982).
The wettest January on record was 2024 with 213 mm. On average, January sees 93 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 Waltham behaves each January, 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 January specifically, along with year-by-year records and how the month has changed over the decades.
