January is one of the warmer months of the year in Somerville, with average highs near 25.5°C and lows around 14.6°C (mean 20.1°C). It is about average for rainfall, averaging 53 mm of rainfall and 65% relative humidity across the period.
January is one of the warmer months of the year in Somerville. Across 45 years of records, the warmest January in Somerville was 2022 — when the month averaged 22.7°C — while the coldest was 1992 at 16.8°C. Typical January days reach 25.5°C with nights near 14.6°C. The long-term trend is warming, about 0.4°C per decade.
January is about average for rainfall in Somerville, averaging 53 mm of rainfall. The wettest January on record was 2024 with 143 mm, while the driest was 2009 at 4 mm.
Relative humidity in Somerville during January averages 65%. The most humid January was 2024 at 76%, and the least humid was 1982 at 57%.
January receives about 6.9 kWh/m²/day of solar energy in Somerville. The sunniest January was 2009 at 7.9 kWh/m²/day, and the cloudiest were 2002, 2016 and 2020 at 6.3.
Average wind speed in Somerville during January is 3.4 m/s. The windiest Januarys were 1990, 1997 and 2012 at 3.8 m/s, while the calmest was 1993 at 2.8 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 19.6°C | 19.6°C | 20.1°C | 20.7°C | 20.6°C | +1°C |
| Avg High | 25.2°C | 24.9°C | 25.6°C | 26.1°C | 25.8°C | +0.6°C |
| Avg Low | 13.9°C | 14.2°C | 14.5°C | 15.2°C | 15.4°C | +1.5°C |
| Avg Rain | 50 mm | 56 mm | 34 mm | 49 mm | 91 mm | +41 mm |
January temperatures in Somerville have risen by about 0.7°C between 1981–1985 and 2021–2025.
January has ranged from a record low of 8.8°C (1994) to a record high of 41.9°C (2009).
Rainfall in January is about average for rainfall, averaging 53 mm, with a wettest year of 143 mm.
One of the best times to visit Somerville
January is one of the best times to visit Somerville. Expect days averaging 25.5°C and nights around 14.6°C (mean 20.1°C) — warmer than Somerville's yearly average — with moderate rainfall (53 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 26.7°C | 21.2°C | 15.8°C | 37.1°C | 11.7°C | 44 mm | 64% | 3.3 m/s | 7.1 |
| 2024 🌧️ | 24.3°C | 19.8°C | 15.2°C | 30.5°C | 12.6°C | 143 mm | 76% | 3.1 m/s | 6.6 |
| 2023 | 25.7°C | 20.5°C | 15.3°C | 34.5°C | 12.4°C | 33 mm | 68% | 3.2 m/s | 7.1 |
| 2022 🔥 | 28.2°C | 22.7°C | 17.3°C | 35.1°C | 13.7°C | 75 mm | 68% | 3.1 m/s | 6.9 |
| 2021 | 24.0°C | 19.2°C | 14.4°C | 34.5°C | 10.7°C | 136 mm | 71% | 3.4 m/s | 6.8 |
| 2020 | 25.8°C | 20.2°C | 14.6°C | 38.1°C | 11.5°C | 116 mm | 67% | 3.2 m/s | 6.3 |
| 2019 | 28.6°C | 22.2°C | 15.9°C | 40.4°C | 12.6°C | 13 mm | 64% | 3.1 m/s | 7.4 |
| 2018 | 26.8°C | 21.3°C | 15.9°C | 39.1°C | 13.0°C | 58 mm | 66% | 3.3 m/s | 7.2 |
| 2017 | 26.1°C | 20.6°C | 15.0°C | 35.1°C | 12.0°C | 43 mm | 65% | 3.2 m/s | 7 |
| 2016 | 25.3°C | 20.4°C | 15.5°C | 38.6°C | 11.9°C | 92 mm | 69% | 3.3 m/s | 6.3 |
| 2015 | 25.2°C | 19.8°C | 14.5°C | 37.6°C | 11.5°C | 54 mm | 66% | 3.7 m/s | 6.7 |
| 2014 | 27.2°C | 21.2°C | 15.2°C | 40.8°C | 9.7°C | 23 mm | 59% | 3.6 m/s | 7.4 |
| 2013 | 26.1°C | 20.3°C | 14.5°C | 37.0°C | 12.4°C | 20 mm | 60% | 3.6 m/s | 7.3 |
| 2012 | 25.9°C | 20.8°C | 15.6°C | 36.4°C | 12.8°C | 40 mm | 64% | 3.8 m/s | 7.1 |
| 2011 | 24.6°C | 20.0°C | 15.5°C | 34.7°C | 10.7°C | 114 mm | 73% | 2.9 m/s | 6.6 |
| 2010 | 25.6°C | 19.9°C | 14.2°C | 38.7°C | 11.5°C | 36 mm | 64% | 3.5 m/s | 7.2 |
| 2009 | 27.0°C | 20.5°C | 14.1°C | 41.9°C | 10.1°C | 4 mm | 59% | 3.3 m/s | 7.9 |
| 2008 | 26.3°C | 20.8°C | 15.3°C | 38.0°C | 12.3°C | 29 mm | 65% | 3.3 m/s | 7.5 |
| 2007 | 25.9°C | 20.6°C | 15.3°C | 37.2°C | 11.9°C | 39 mm | 64% | 3.4 m/s | 6.5 |
| 2006 | 26.3°C | 20.7°C | 15.1°C | 38.3°C | 11.7°C | 52 mm | 66% | 3.4 m/s | 7 |
| 2005 | 25.0°C | 19.8°C | 14.6°C | 34.8°C | 10.9°C | 44 mm | 67% | 3.3 m/s | 7.1 |
| 2004 | 23.6°C | 18.3°C | 13.1°C | 33.9°C | 9.4°C | 42 mm | 65% | 3.4 m/s | 6.9 |
| 2003 | 26.0°C | 20.1°C | 14.2°C | 39.2°C | 10.6°C | 18 mm | 60% | 3.5 m/s | 7 |
| 2002 | 24.1°C | 18.9°C | 13.8°C | 34.7°C | 10.9°C | 42 mm | 68% | 3.6 m/s | 6.3 |
| 2001 | 28.1°C | 22.0°C | 15.9°C | 38.4°C | 12.8°C | 22 mm | 62% | 3.3 m/s | 6.7 |
| 2000 | 24.1°C | 19.1°C | 14.1°C | 32.9°C | 9.7°C | 52 mm | 66% | 3.5 m/s | 6.6 |
| 1999 | 26.2°C | 20.7°C | 15.2°C | 34.8°C | 12.7°C | 36 mm | 71% | 3.3 m/s | 7.1 |
| 1998 | 25.9°C | 20.5°C | 15.0°C | 36.2°C | 11.9°C | 58 mm | 67% | 3.3 m/s | 6.9 |
| 1997 | 26.5°C | 20.6°C | 14.6°C | 37.4°C | 11.2°C | 43 mm | 60% | 3.8 m/s | 7.3 |
| 1996 | 24.2°C | 18.7°C | 13.2°C | 35.4°C | 10.5°C | 52 mm | 69% | 3.5 m/s | 6.8 |
| 1995 | 26.4°C | 20.8°C | 15.3°C | 35.7°C | 10.3°C | 82 mm | 67% | 3.1 m/s | 6.6 |
| 1994 | 23.4°C | 17.8°C | 12.1°C | 36.1°C | 8.8°C | 45 mm | 67% | 3.6 m/s | 6.8 |
| 1993 | 24.8°C | 19.6°C | 14.4°C | 35.3°C | 10.8°C | 101 mm | 72% | 2.8 m/s | 6.7 |
| 1992 ❄️ | 21.0°C | 16.8°C | 12.5°C | 33.9°C | 10.1°C | 29 mm | 71% | 3.6 m/s | 6.6 |
| 1991 | 25.0°C | 19.9°C | 14.8°C | 37.1°C | 11.5°C | 105 mm | 67% | 3.4 m/s | 6.8 |
| 1990 | 25.9°C | 20.3°C | 14.6°C | 36.2°C | 10.4°C | 6 mm | 59% | 3.8 m/s | 7.3 |
| 1989 | 24.6°C | 19.2°C | 13.8°C | 35.3°C | 10.5°C | 57 mm | 65% | 3.4 m/s | 7.1 |
| 1988 | 27.0°C | 21.1°C | 15.2°C | 37.7°C | 11.2°C | 69 mm | 63% | 3.1 m/s | 7.4 |
| 1987 | 23.7°C | 18.2°C | 12.6°C | 33.5°C | 8.9°C | 58 mm | 64% | 3.3 m/s | 6.8 |
| 1986 | 22.6°C | 17.6°C | 12.7°C | 32.3°C | 10.9°C | 32 mm | 67% | 3.7 m/s | 7.1 |
| 1985 | 24.1°C | 18.7°C | 13.3°C | 37.8°C | 10.3°C | 18 mm | 61% | 3.7 m/s | 7 |
| 1984 | 23.8°C | 18.9°C | 14.0°C | 30.8°C | 10.7°C | 70 mm | 65% | 3.7 m/s | 6.4 |
| 1983 | 24.4°C | 18.5°C | 12.6°C | 37.5°C | 10.2°C | 34 mm | 59% | 3.5 m/s | — |
| 1982 | 27.6°C | 21.5°C | 15.3°C | 40.9°C | 11.5°C | 51 mm | 57% | 3.5 m/s | — |
| 1981 | 28.9°C | 22.4°C | 15.9°C | 39.3°C | 12.4°C | 62 mm | 61% | 3.5 m/s | — |
Actual recorded January data for each year, 1981–2025 — sourced from NASA POWER.
The average high in January is around 25.5°C with lows near 14.6°C (mean 20.1°C), based on 45 years of NASA POWER data.
January averages 53 mm of rainfall in Somerville, about average for rainfall. The wettest on record was 143 mm in 2024.
The hottest January reached 41.9°C in 2009. The coldest dipped to 8.8°C in 1994.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average January temperatures have risen by about 0.7°C. Daytime highs moved from 25.8°C to 25.8°C and overnight lows from 14.2°C to 15.6°C over the same span.
January is one of the warmer months of the year in Somerville and about average for rainfall, so plan for around 25.5°C daytime highs and 14.6°C at night.
Not quite — January is the 11th coolest month in Somerville, averaging 20.1°C.
For January in Somerville, pack light layers you can adjust through the day, with typical highs of 25.5°C and lows of 14.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in January averages 65% — moderately humid.
Average wind speed in January is 3.4 m/s. The windiest January on record averaged 3.8 m/s (1990).
The wettest January on record was 2024 with 143 mm. On average, January sees 53 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 Somerville 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.
