December is one of the cooler months of the year in West Siang, with average highs near 25°C and lows around 6°C (mean 15.5°C). It is one of the drier months, averaging 12 mm of rainfall and 73% relative humidity across the period.
December is one of the cooler months of the year in West Siang. Across 45 years of records, the warmest December in West Siang was 2016 — when the month averaged 18°C — while the coldest were 1982 and 2009 at 13.1°C. Typical December days reach 25°C with nights near 6°C. The long-term trend is warming, about 0.2°C per decade.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 15.2°C | 15.1°C | 15.7°C | 15.9°C | 15.7°C | +0.5°C |
| Avg High | 24.9°C | 24.7°C | 25.6°C | 25.3°C | 24.4°C | -0.5°C |
| Avg Low | 5.4°C | 5.5°C | 5.9°C | 6.6°C | 7.0°C | +1.6°C |
| Avg Rain | 25 mm | 10 mm | 6 mm | 10 mm | 13 mm | -12 mm |
December temperatures in West Siang have risen by about 1.4°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 3.9°C (1982) to a record high of 29.2°C (1998).
Rainfall in December is one of the drier months, averaging 12 mm, with a wettest year of 85 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0°C per decade while lows rose 0.5°C per decade, narrowing the gap between day and night.
A good time to visit West Siang
December is a good time to visit West Siang, with days averaging 25°C and nights around 6°C (mean 15.5°C, cooler than West Siang's yearly average) and low rainfall. October and November are marginally more temperate, but December still suits most travellers.
| Year | High | Low | Avg | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|
| 2025 | 24.3°C | 8.2°C | 16.2°C | 4 mm | 72% | 0.6 m/s | — |
| 2024 | 23.4°C | 6.7°C | 15.1°C | 2 mm | 72% | 0.6 m/s | 3 |
| 2023 | 25.5°C | 7.9°C | 16.7°C | 15 mm | 75% | 0.5 m/s | 3.1 |
| 2022 | 24.8°C | 6.3°C | 15.5°C | 29 mm | 78% | 0.5 m/s | 2.5 |
| 2021 | 24.9°C | 6.0°C | 15.4°C | 14 mm | 76% | 0.5 m/s | 3 |
| 2020 | 23.3°C | 7.0°C | 15.1°C | 12 mm | 79% | 0.4 m/s | 2.8 |
| 2019 | 26.1°C | 5.5°C | 15.8°C | 3 mm | 78% | 0.4 m/s | 2.8 |
| 2018 | 23.5°C | 7.2°C | 15.3°C | 19 mm | 74% | 0.5 m/s | 3.1 |
| 2017 | 26.5°C | 8.7°C | 17.6°C | 1 mm | 77% | 0.5 m/s | 3.3 |
| 2016 🔥 | 28.3°C | 7.7°C | 18.0°C | 7 mm | 73% | 0.5 m/s | 3.4 |
| 2015 | 24.2°C | 5.5°C | 14.8°C | 13 mm | 78% | 0.4 m/s | 2.6 |
| 2014 | 25.8°C | 7.9°C | 16.8°C | 2 mm | 77% | 0.4 m/s | 3 |
| 2013 | 24.0°C | 5.4°C | 14.7°C | 7 mm | 79% | 0.4 m/s | 2.8 |
| 2012 | 23.8°C | 7.0°C | 15.4°C | 15 mm | 79% | 0.4 m/s | 2.9 |
| 2011 | 24.1°C | 5.7°C | 14.9°C | 25 mm | 73% | 0.5 m/s | 2.8 |
| 2010 | 26.2°C | 5.4°C | 15.8°C | 5 mm | 71% | 0.6 m/s | 3.5 |
| 2009 | 20.8°C | 5.4°C | 13.1°C | 8 mm | 80% | 0.5 m/s | 2.4 |
| 2008 | 24.1°C | 5.9°C | 15.0°C | 2 mm | 77% | 0.5 m/s | 3 |
| 2007 | 25.2°C | 5.8°C | 15.5°C | 6 mm | 69% | 0.5 m/s | 3.2 |
| 2006 | 26.0°C | 7.0°C | 16.5°C | 12 mm | 72% | 0.5 m/s | 2.9 |
| 2005 | 25.3°C | 6.9°C | 16.1°C | 0 mm | 67% | 0.5 m/s | 3.6 |
| 2004 | 24.7°C | 4.5°C | 14.6°C | 15 mm | 73% | 0.5 m/s | 3.1 |
| 2003 | 27.8°C | 6.1°C | 16.9°C | 3 mm | 70% | 0.5 m/s | 3.1 |
| 2002 | 28.4°C | 6.0°C | 17.2°C | 2 mm | 71% | 0.5 m/s | 3.1 |
| 2001 | 26.9°C | 5.4°C | 16.1°C | 6 mm | 65% | 0.5 m/s | 3.1 |
| 2000 | 26.6°C | 6.2°C | 16.4°C | 2 mm | 62% | 0.5 m/s | 3.4 |
| 1999 | 26.6°C | 5.4°C | 16.0°C | 1 mm | 68% | 0.5 m/s | 3.2 |
| 1998 | 29.2°C | 5.5°C | 17.3°C | 4 mm | 61% | 0.5 m/s | 3.4 |
| 1997 | 22.0°C | 5.0°C | 13.5°C | 25 mm | 72% | 0.5 m/s | 2.8 |
| 1996 | 23.6°C | 6.2°C | 14.9°C | 0 mm | 67% | 0.5 m/s | 3.4 |
| 1995 | 20.9°C | 5.8°C | 13.3°C | 23 mm | 77% | 0.4 m/s | 2.7 |
| 1994 | 25.9°C | 4.9°C | 15.4°C | 0 mm | 65% | 0.5 m/s | 3.2 |
| 1993 | 25.5°C | 6.4°C | 16.0°C | 0 mm | 69% | 0.5 m/s | 3.1 |
| 1992 | 22.0°C | 4.5°C | 13.3°C | 3 mm | 68% | 0.6 m/s | 3.2 |
| 1991 | 26.9°C | 4.6°C | 15.8°C | 43 mm | 72% | 0.5 m/s | 3.1 |
| 1990 | 24.1°C | 6.8°C | 15.4°C | 0 mm | 73% | 0.5 m/s | 3.2 |
| 1989 | 26.0°C | 4.9°C | 15.5°C | 14 mm | 69% | 0.6 m/s | 3.2 |
| 1988 | 26.3°C | 6.6°C | 16.5°C | 10 mm | 74% | 0.5 m/s | 3.1 |
| 1987 | 26.1°C | 7.1°C | 16.6°C | 16 mm | 68% | 0.5 m/s | 3.4 |
| 1986 | 27.5°C | 4.5°C | 16.0°C | 12 mm | 70% | 0.5 m/s | 3.1 |
| 1985 🌧️ | 24.5°C | 5.8°C | 15.2°C | 85 mm | 75% | 0.5 m/s | 3.1 |
| 1984 | 23.2°C | 5.2°C | 14.2°C | 23 mm | 73% | 0.5 m/s | 2.9 |
| 1983 | 22.7°C | 5.1°C | 13.9°C | 33 mm | 72% | 0.5 m/s | — |
| 1982 ❄️ | 22.3°C | 3.9°C | 13.1°C | 9 mm | 74% | 0.5 m/s | — |
| 1981 | 25.3°C | 5.7°C | 15.5°C | 22 mm | 76% | 0.5 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 25°C with lows near 6°C (mean 15.5°C), based on 45 years of NASA POWER data.
December averages 12 mm of rainfall in West Siang, one of the drier months. The wettest on record was 85 mm in 1985.
The hottest December reached 29.2°C in 1998. The coldest dipped to 3.9°C in 1982.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 1.4°C. Daytime highs moved from 23.6°C to 24.6°C and overnight lows from 5.1°C to 7°C over the same span.
December is one of the cooler months of the year in West Siang and one of the drier months, so plan for around 25°C daytime highs and 6°C at night.
Not quite — December is the 3rd coolest month in West Siang, averaging 15.5°C.
For December in West Siang, pack warm layers and a jacket for chilly mornings, with typical highs of 25°C and lows of 6°C.
Relative humidity in December averages 73% — moderately humid.
Average wind speed in December is 0.5 m/s. The windiest December on record averaged 0.6 m/s (1989).
The wettest December on record was 1985 with 85 mm. On average, December sees 12 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 West Siang 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.
