December is one of the cooler months of the year in Bothell, with average highs near 5.9°C and lows around 1.4°C (mean 3.7°C). It is a relatively wet time of year, averaging 179 mm of rainfall and 91% relative humidity across the period.
December is one of the cooler months of the year in Bothell. Across 45 years of records, the warmest December in Bothell was 2023 — when the month averaged 6.7°C — while the coldest was 1983 at -0.2°C. Typical December days reach 5.9°C with nights near 1.4°C. The long-term trend is warming, about 0.3°C per decade.
December is a relatively wet time of year in Bothell, averaging 179 mm of rainfall. The wettest December on record was 1996 with 302 mm, while the driest was 1985 at 43 mm.
Relative humidity in Bothell during December averages 91%. The most humid December was 2025 at 96%, and the least humid was 2009 at 85%.
December receives about 0.9 kWh/m²/day of solar energy in Bothell. The sunniest Decembers were 1985 and 2009 at 1.1 kWh/m²/day, and the cloudiest were 2012, 2015 and 2019, among others at 0.7.
Average wind speed in Bothell during December is 0.8 m/s. The windiest Decembers were 2010, 2015 and 2018, among others at 1 m/s, while the calmest were 2013, 2017 and 2019, among others at 0.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 3.0°C | 3.5°C | 3.8°C | 3.8°C | 4.3°C | +1.3°C |
| Avg High | 5.4°C | 5.8°C | 6.1°C | 6.0°C | 6.4°C | +1°C |
| Avg Low | 0.6°C | 1.2°C | 1.5°C | 1.7°C | 2.2°C | +1.6°C |
| Avg Rain | 156 mm | 197 mm | 160 mm | 172 mm | 223 mm | +67 mm |
December temperatures in Bothell have risen by about 2°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -16.3°C (1985) to a record high of 14.7°C (2002).
Rainfall in December is a relatively wet time of year, averaging 179 mm, with a wettest year of 302 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.2°C per decade while lows rose 0.4°C per decade, narrowing the gap between day and night.
A quieter season to visit Bothell
If your dates are flexible, the more temperate months of August and July tend to be the most comfortable for visiting Bothell. That said, December — with days averaging 5.9°C and nights around 1.4°C (mean 3.7°C) and higher rainfall (179 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 | 6.8°C | 5.0°C | 3.1°C | 13.4°C | -1.7°C | 301 mm | 96% | 0.8 m/s | — |
| 2024 | 6.4°C | 4.5°C | 2.5°C | 8.2°C | -0.4°C | 217 mm | 95% | 0.8 m/s | 0.9 |
| 2023 🔥 | 9.1°C | 6.7°C | 4.2°C | 13.3°C | 0.0°C | 220 mm | 93% | 0.8 m/s | 0.8 |
| 2022 | 4.7°C | 2.4°C | 0.1°C | 11.3°C | -12.1°C | 207 mm | 93% | 0.9 m/s | 0.8 |
| 2021 | 3.8°C | 1.8°C | -0.1°C | 12.3°C | -11.1°C | 193 mm | 93% | 0.9 m/s | 0.8 |
| 2020 | 7.7°C | 5.4°C | 3.1°C | 11.5°C | -0.4°C | 199 mm | 92% | 0.9 m/s | 0.9 |
| 2019 | 7.1°C | 5.2°C | 3.2°C | 10.7°C | -1.5°C | 175 mm | 94% | 0.7 m/s | 0.7 |
| 2018 | 7.1°C | 4.8°C | 2.5°C | 12.3°C | -2.4°C | 209 mm | 90% | 1 m/s | 0.9 |
| 2017 | 5.9°C | 3.4°C | 0.9°C | 9.9°C | -4.5°C | 149 mm | 90% | 0.7 m/s | 1 |
| 2016 | 3.3°C | 1.5°C | -0.4°C | 7.3°C | -4.5°C | 137 mm | 90% | 0.9 m/s | 0.9 |
| 2015 | 6.1°C | 4.3°C | 2.4°C | 13.0°C | -3.6°C | 286 mm | 92% | 1 m/s | 0.7 |
| 2014 | 7.8°C | 5.3°C | 2.9°C | 14.6°C | -3.9°C | 175 mm | 88% | 0.9 m/s | 1 |
| 2013 | 4.6°C | 2.2°C | -0.2°C | 9.6°C | -8.4°C | 86 mm | 87% | 0.7 m/s | 0.9 |
| 2012 | 5.5°C | 3.9°C | 2.3°C | 9.4°C | -0.5°C | 215 mm | 94% | 0.9 m/s | 0.7 |
| 2011 | 5.7°C | 3.4°C | 1.0°C | 9.6°C | -2.8°C | 88 mm | 91% | 0.7 m/s | 1 |
| 2010 | 6.5°C | 4.3°C | 2.1°C | 11.3°C | -4.5°C | 205 mm | 91% | 1 m/s | 0.8 |
| 2009 | 4.8°C | 2.2°C | -0.3°C | 10.7°C | -7.3°C | 80 mm | 85% | 0.8 m/s | 1.1 |
| 2008 | 3.6°C | 1.4°C | -0.7°C | 11.3°C | -10.7°C | 142 mm | 90% | 0.8 m/s | 0.8 |
| 2007 | 5.3°C | 3.2°C | 1.2°C | 13.9°C | -1.7°C | 241 mm | 93% | 0.9 m/s | 0.7 |
| 2006 | 6.3°C | 4.1°C | 2.0°C | 10.4°C | -1.7°C | 190 mm | 91% | 0.9 m/s | 0.8 |
| 2005 | 6.4°C | 4.2°C | 1.9°C | 14.0°C | -4.0°C | 191 mm | 89% | 0.8 m/s | 0.9 |
| 2004 | 7.7°C | 5.3°C | 3.0°C | 13.0°C | 0.4°C | 172 mm | 92% | 0.7 m/s | 0.8 |
| 2003 | 6.5°C | 4.4°C | 2.2°C | 10.2°C | -4.6°C | 134 mm | 92% | 0.9 m/s | 0.8 |
| 2002 | 8.0°C | 5.5°C | 3.0°C | 14.7°C | -1.1°C | 175 mm | 91% | 0.9 m/s | 0.7 |
| 2001 | 6.5°C | 4.0°C | 1.4°C | 9.7°C | -2.1°C | 188 mm | 91% | 1 m/s | 0.9 |
| 2000 | 6.1°C | 3.8°C | 1.4°C | 9.3°C | -3.2°C | 89 mm | 89% | 0.7 m/s | 0.9 |
| 1999 | 7.2°C | 4.9°C | 2.7°C | 11.4°C | -0.1°C | 185 mm | 93% | 0.8 m/s | 0.8 |
| 1998 | 5.2°C | 3.1°C | 1.1°C | 12.6°C | -9.2°C | 251 mm | 90% | 1 m/s | 0.8 |
| 1997 | 7.2°C | 4.7°C | 2.2°C | 11.2°C | -0.5°C | 130 mm | 91% | 0.9 m/s | 1 |
| 1996 🌧️ | 4.5°C | 2.4°C | 0.4°C | 11.4°C | -6.0°C | 302 mm | 94% | 0.9 m/s | 0.8 |
| 1995 | 6.4°C | 4.0°C | 1.6°C | 9.8°C | -6.1°C | 216 mm | 91% | 0.9 m/s | 0.8 |
| 1994 | 5.9°C | 3.6°C | 1.4°C | 12.0°C | -4.6°C | 249 mm | 90% | 0.9 m/s | 0.9 |
| 1993 | 7.0°C | 4.5°C | 2.0°C | 13.1°C | -1.8°C | 187 mm | 88% | 0.8 m/s | 0.8 |
| 1992 | 4.1°C | 1.9°C | -0.3°C | 9.2°C | -7.6°C | 147 mm | 91% | 0.9 m/s | 0.9 |
| 1991 | 7.1°C | 4.9°C | 2.7°C | 11.1°C | -0.9°C | 128 mm | 92% | 0.8 m/s | 0.9 |
| 1990 | 3.4°C | 0.7°C | -2.0°C | 9.6°C | -14.8°C | 172 mm | 86% | 0.9 m/s | 0.8 |
| 1989 | 7.6°C | 5.2°C | 2.8°C | 13.1°C | -1.3°C | 132 mm | 92% | 0.7 m/s | 0.9 |
| 1988 | 6.5°C | 4.1°C | 1.8°C | 11.0°C | -3.5°C | 133 mm | 91% | 0.8 m/s | 0.8 |
| 1987 | 5.2°C | 2.9°C | 0.7°C | 12.4°C | -4.4°C | 192 mm | 89% | 0.9 m/s | 0.8 |
| 1986 | 6.7°C | 4.1°C | 1.6°C | 9.9°C | -3.0°C | 134 mm | 91% | 0.8 m/s | 0.8 |
| 1985 | 5.3°C | 2.4°C | -0.4°C | 8.6°C | -16.3°C | 43 mm | 89% | 0.7 m/s | 1.1 |
| 1984 | 2.9°C | 0.7°C | -1.5°C | 6.9°C | -6.7°C | 171 mm | 90% | 0.8 m/s | 1 |
| 1983 ❄️ | 2.3°C | -0.2°C | -2.6°C | 7.4°C | -13.4°C | 142 mm | 86% | 0.8 m/s | — |
| 1982 | 6.1°C | 3.7°C | 1.3°C | 12.0°C | -2.8°C | 236 mm | 90% | 0.8 m/s | — |
| 1981 | 5.9°C | 3.7°C | 1.6°C | 11.1°C | -4.1°C | 222 mm | 92% | 0.9 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 5.9°C with lows near 1.4°C (mean 3.7°C), based on 45 years of NASA POWER data.
December averages 179 mm of rainfall in Bothell, a relatively wet time of year. The wettest on record was 302 mm in 1996.
The hottest December reached 14.7°C in 2002. The coldest dipped to -16.3°C in 1985.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 2°C. Daytime highs moved from 4.5°C to 6.2°C and overnight lows from -0.3°C to 2°C over the same span.
December is one of the cooler months of the year in Bothell and a relatively wet time of year, so plan for around 5.9°C daytime highs and 1.4°C at night.
Yes — December is the coldest month of the year in Bothell, averaging 3.7°C.
For December in Bothell, pack warm layers and a jacket for chilly mornings, with typical highs of 5.9°C and lows of 1.4°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 91% — quite humid.
Average wind speed in December is 0.8 m/s. The windiest December on record averaged 1 m/s (1998).
The wettest December on record was 1996 with 302 mm. On average, December sees 179 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 Bothell 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.
