December is one of the warmer months of the year in Northam, with average highs near 33.2°C and lows around 15.5°C (mean 24.4°C). It is one of the drier months, averaging 11 mm of rainfall and 40% relative humidity across the period.
December is one of the warmer months of the year in Northam. Across 45 years of records, the warmest December in Northam was 2019 — when the month averaged 28.2°C — while the coldest was 2005 at 21°C. Typical December days reach 33.2°C with nights near 15.5°C. The long-term trend is warming, about 0.5°C per decade.
December is one of the drier months in Northam, averaging 11 mm of rainfall. The wettest December on record was 1991 with 44 mm, while the driest were 1986, 1997 and 2023 at 1 mm.
Relative humidity in Northam during December averages 40%. The most humid December was 2005 at 50%, and the least humid was 2019 at 32%.
December receives about 8.5 kWh/m²/day of solar energy in Northam. The sunniest Decembers were 2014, 2016 and 2020, among others at 8.9 kWh/m²/day, and the cloudiest was 2011 at 7.6.
Average wind speed in Northam during December is 4 m/s. The windiest December was 1993 at 4.5 m/s, while the calmest was 2012 at 3.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 23.4°C | 24.3°C | 24.1°C | 24.8°C | 25.5°C | +2.1°C |
| Avg High | 32.1°C | 33.2°C | 33.1°C | 33.5°C | 34.5°C | +2.4°C |
| Avg Low | 14.6°C | 15.5°C | 15.2°C | 16.0°C | 16.5°C | +1.9°C |
| Avg Rain | 12 mm | 12 mm | 10 mm | 15 mm | 3 mm | -9 mm |
December temperatures in Northam have risen by about 2.7°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 6.6°C (2020) to a record high of 45.2°C (1997).
Rainfall in December is one of the drier months, averaging 11 mm, with a wettest year of 44 mm.
One of the best times to visit Northam
December is one of the best times to visit Northam. Expect days averaging 33.2°C and nights around 15.5°C (mean 24.4°C) — warmer than Northam's yearly average — with low rainfall (11 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 | 34.7°C | 25.4°C | 16.2°C | 41.6°C | 11.6°C | 12 mm | 38% | 4.2 m/s | — |
| 2024 | 35.9°C | 26.7°C | 17.5°C | 43.7°C | 10.9°C | 3 mm | 37% | 4 m/s | 8.7 |
| 2023 | 34.6°C | 26.0°C | 17.4°C | 39.4°C | 11.8°C | 1 mm | 37% | 4.3 m/s | 8.6 |
| 2022 | 33.1°C | 24.4°C | 15.8°C | 40.5°C | 11.4°C | 1 mm | 41% | 4.1 m/s | 8.6 |
| 2021 | 34.7°C | 25.6°C | 16.6°C | 42.1°C | 11.2°C | 2 mm | 39% | 4 m/s | 8.8 |
| 2020 | 34.1°C | 24.9°C | 15.7°C | 43.1°C | 6.6°C | 1 mm | 36% | 4 m/s | 8.9 |
| 2019 🔥 | 37.7°C | 28.2°C | 18.6°C | 43.6°C | 11.5°C | 1 mm | 32% | 3.7 m/s | 8.7 |
| 2018 | 34.2°C | 25.2°C | 16.2°C | 40.8°C | 10.3°C | 7 mm | 39% | 3.6 m/s | 8.6 |
| 2017 | 33.1°C | 24.5°C | 15.9°C | 39.5°C | 11.1°C | 15 mm | 38% | 3.8 m/s | 8.4 |
| 2016 | 32.4°C | 23.5°C | 14.6°C | 41.4°C | 10.9°C | 16 mm | 42% | 4 m/s | 8.9 |
| 2015 | 32.8°C | 24.2°C | 15.6°C | 42.4°C | 9.8°C | 16 mm | 40% | 4 m/s | 8.5 |
| 2014 | 32.7°C | 23.7°C | 14.7°C | 43.7°C | 10.9°C | 3 mm | 39% | 3.9 m/s | 8.9 |
| 2013 | 34.5°C | 25.3°C | 16.1°C | 43.3°C | 10.7°C | 3 mm | 36% | 3.8 m/s | 8.6 |
| 2012 | 33.9°C | 25.2°C | 16.6°C | 42.7°C | 7.2°C | 28 mm | 45% | 3.5 m/s | 8.1 |
| 2011 | 32.1°C | 24.1°C | 16.0°C | 38.5°C | 12.7°C | 34 mm | 49% | 3.7 m/s | 7.6 |
| 2010 | 32.0°C | 23.9°C | 15.7°C | 42.5°C | 9.5°C | 21 mm | 42% | 4.1 m/s | 7.7 |
| 2009 | 34.5°C | 25.2°C | 15.9°C | 44.1°C | 10.8°C | 7 mm | 34% | 4 m/s | 8.9 |
| 2008 | 32.3°C | 23.5°C | 14.7°C | 40.8°C | 9.9°C | 7 mm | 44% | 3.7 m/s | 8.6 |
| 2007 | 30.4°C | 22.4°C | 14.5°C | 42.6°C | 7.2°C | 41 mm | 47% | 4.1 m/s | 7.8 |
| 2006 | 34.2°C | 25.2°C | 16.1°C | 42.4°C | 10.0°C | 13 mm | 37% | 3.7 m/s | 8.4 |
| 2005 ❄️ | 29.5°C | 21.0°C | 12.4°C | 43.2°C | 9.5°C | 3 mm | 50% | 4 m/s | 8.7 |
| 2004 | 34.8°C | 25.4°C | 16.1°C | 42.4°C | 10.2°C | 3 mm | 39% | 4.3 m/s | 8.6 |
| 2003 | 34.0°C | 24.6°C | 15.1°C | 43.1°C | 8.3°C | 7 mm | 40% | 4.1 m/s | 8.7 |
| 2002 | 34.2°C | 25.3°C | 16.4°C | 43.8°C | 8.3°C | 12 mm | 39% | 4.4 m/s | 8.3 |
| 2001 | 30.7°C | 22.3°C | 13.9°C | 37.2°C | 9.6°C | 1 mm | 42% | 4.1 m/s | 8.4 |
| 2000 | 35.9°C | 26.3°C | 16.7°C | 41.6°C | 9.3°C | 3 mm | 34% | 3.9 m/s | 8.8 |
| 1999 | 33.8°C | 25.6°C | 17.3°C | 41.4°C | 10.7°C | 29 mm | 39% | 4 m/s | 8.1 |
| 1998 | 33.4°C | 24.9°C | 16.3°C | 41.7°C | 7.6°C | 11 mm | 42% | 4 m/s | 8.1 |
| 1997 | 35.3°C | 25.7°C | 16.2°C | 45.2°C | 11.0°C | 1 mm | 35% | 4.1 m/s | 8.9 |
| 1996 | 31.7°C | 22.8°C | 13.9°C | 40.2°C | 8.7°C | 4 mm | 42% | 4.3 m/s | 8.8 |
| 1995 | 31.0°C | 22.7°C | 14.5°C | 38.9°C | 10.2°C | 15 mm | 46% | 4.3 m/s | 8.2 |
| 1994 | 34.9°C | 25.6°C | 16.4°C | 42.5°C | 10.7°C | 2 mm | 35% | 4.1 m/s | 8.9 |
| 1993 | 33.4°C | 24.2°C | 15.1°C | 42.3°C | 10.0°C | 4 mm | 35% | 4.5 m/s | 8.8 |
| 1992 | 32.3°C | 23.1°C | 13.9°C | 41.2°C | 9.5°C | 4 mm | 41% | 4.1 m/s | 8.7 |
| 1991 🌧️ | 33.0°C | 24.5°C | 15.9°C | 41.8°C | 11.2°C | 44 mm | 43% | 3.7 m/s | 8.2 |
| 1990 | 33.0°C | 24.0°C | 15.0°C | 39.9°C | 8.9°C | 3 mm | 40% | 4 m/s | 8.8 |
| 1989 | 32.4°C | 23.3°C | 14.1°C | 39.3°C | 10.2°C | 2 mm | 41% | 3.9 m/s | 8.4 |
| 1988 | 32.2°C | 23.8°C | 15.3°C | 41.3°C | 9.2°C | 19 mm | 43% | 4 m/s | 8.5 |
| 1987 | 33.7°C | 24.9°C | 16.1°C | 42.8°C | 8.9°C | 23 mm | 42% | 3.7 m/s | 8.6 |
| 1986 | 33.0°C | 23.7°C | 14.5°C | 42.8°C | 8.8°C | 1 mm | 37% | 3.9 m/s | 8.5 |
| 1985 | 30.3°C | 21.5°C | 12.8°C | 40.2°C | 8.7°C | 3 mm | 42% | 4.1 m/s | 8.7 |
| 1984 | 31.4°C | 22.4°C | 13.4°C | 39.9°C | 8.1°C | 7 mm | 41% | 3.6 m/s | 8.5 |
| 1983 | 32.1°C | 23.7°C | 15.4°C | 40.3°C | 9.4°C | 28 mm | 49% | 4 m/s | — |
| 1982 | 33.5°C | 24.8°C | 16.0°C | 41.7°C | 11.3°C | 7 mm | 43% | 3.8 m/s | — |
| 1981 | 30.7°C | 22.1°C | 13.5°C | 38.8°C | 9.8°C | 19 mm | 43% | 4 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 33.2°C with lows near 15.5°C (mean 24.4°C), based on 45 years of NASA POWER data.
December averages 11 mm of rainfall in Northam, one of the drier months. The wettest on record was 44 mm in 1991.
The hottest December reached 45.2°C in 1997. The coldest dipped to 6.6°C in 2020.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 2.7°C. Daytime highs moved from 31.6°C to 34.6°C and overnight lows from 14.2°C to 16.7°C over the same span.
December is one of the warmer months of the year in Northam and one of the drier months, so plan for around 33.2°C daytime highs and 15.5°C at night.
Not quite — December is the 10th coolest month in Northam, averaging 24.4°C.
For December in Northam, pack light, breathable clothing and sun protection, with typical highs of 33.2°C and lows of 15.5°C.
Relative humidity in December averages 40% — relatively dry.
Average wind speed in December is 4 m/s. The windiest December on record averaged 4.5 m/s (1993).
The wettest December on record was 1991 with 44 mm. On average, December sees 11 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 Northam 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.
