December is one of the cooler months of the year in Brownsville, with average highs near 23.5°C and lows around 13.9°C (mean 18.7°C). It is one of the drier months, averaging 30 mm of rainfall and 75% relative humidity across the period.
December is one of the cooler months of the year in Brownsville. Across 45 years of records, the warmest December in Brownsville was 2021 — when the month averaged 22.2°C — while the coldest was 1989 at 12.8°C. Typical December days reach 23.5°C with nights near 13.9°C. The long-term trend is warming, about 0.4°C per decade.
December is one of the drier months in Brownsville, averaging 30 mm of rainfall. The wettest December on record was 2009 with 121 mm, while the driest was 2010 at 1 mm.
Relative humidity in Brownsville during December averages 75%. The most humid December was 2009 at 82%, and the least humid was 1999 at 66%.
December receives about 2.9 kWh/m²/day of solar energy in Brownsville. The sunniest December was 2010 at 3.7 kWh/m²/day, and the cloudiest was 1986 at 2.
Average wind speed in Brownsville during December is 3.5 m/s. The windiest December was 2008 at 4.1 m/s, while the calmest was 2023 at 2.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 17.9°C | 18.8°C | 18.1°C | 18.9°C | 20.2°C | +2.3°C |
| Avg High | 22.7°C | 23.4°C | 22.9°C | 23.7°C | 25.2°C | +2.5°C |
| Avg Low | 13.2°C | 14.2°C | 13.3°C | 14.0°C | 15.2°C | +2°C |
| Avg Rain | 34 mm | 31 mm | 33 mm | 28 mm | 24 mm | -10 mm |
December temperatures in Brownsville have risen by about 2°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -7.1°C (1989) to a record high of 32.7°C (1983).
Rainfall in December is one of the drier months, averaging 30 mm, with a wettest year of 121 mm.
One of the best times to visit Brownsville
December is one of the best times to visit Brownsville. Expect days averaging 23.5°C and nights around 13.9°C (mean 18.7°C) — cooler than Brownsville's yearly average — with moderate rainfall (30 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 | 25.9°C | 20.7°C | 15.6°C | 30.4°C | 8.7°C | 24 mm | 77% | 2.9 m/s | — |
| 2024 | 26.8°C | 21.9°C | 17.0°C | 31.7°C | 6.7°C | 34 mm | 77% | 3.1 m/s | 3.1 |
| 2023 | 24.1°C | 19.3°C | 14.5°C | 29.0°C | 6.7°C | 18 mm | 78% | 2.4 m/s | 3 |
| 2022 | 23.8°C | 18.8°C | 13.7°C | 29.4°C | -1.0°C | 14 mm | 78% | 3.4 m/s | 3.3 |
| 2021 🔥 | 26.8°C | 22.2°C | 17.7°C | 30.9°C | 8.9°C | 33 mm | 82% | 3.7 m/s | 3.4 |
| 2020 | 23.8°C | 18.1°C | 12.4°C | 30.9°C | 3.1°C | 22 mm | 67% | 3.5 m/s | 3.5 |
| 2019 | 24.2°C | 18.9°C | 13.6°C | 30.8°C | 5.9°C | 17 mm | 73% | 3.3 m/s | 3.3 |
| 2018 | 23.5°C | 18.2°C | 13.0°C | 28.5°C | 5.4°C | 13 mm | 72% | 3.6 m/s | 3.2 |
| 2017 | 22.2°C | 17.3°C | 12.3°C | 30.0°C | 1.8°C | 26 mm | 77% | 3.3 m/s | 2.5 |
| 2016 | 25.5°C | 20.7°C | 15.9°C | 30.2°C | 3.2°C | 22 mm | 78% | 3.7 m/s | 2.7 |
| 2015 | 24.9°C | 20.1°C | 15.2°C | 31.3°C | 7.7°C | 6 mm | 75% | 3.8 m/s | 3 |
| 2014 | 23.6°C | 19.5°C | 15.4°C | 27.7°C | 6.5°C | 47 mm | 82% | 3.4 m/s | 2.6 |
| 2013 | 21.1°C | 16.4°C | 11.6°C | 30.9°C | 3.7°C | 89 mm | 79% | 3.5 m/s | 2.4 |
| 2012 | 25.7°C | 20.7°C | 15.6°C | 30.6°C | 6.0°C | 7 mm | 69% | 4 m/s | 3.2 |
| 2011 | 22.9°C | 18.3°C | 13.6°C | 28.2°C | 4.4°C | 49 mm | 75% | 3.8 m/s | 2.7 |
| 2010 | 23.9°C | 18.8°C | 13.7°C | 30.7°C | 4.2°C | 1 mm | 69% | 3.9 m/s | 3.7 |
| 2009 🌧️ | 19.9°C | 15.4°C | 10.8°C | 30.8°C | 0.9°C | 121 mm | 82% | 3.5 m/s | 2.3 |
| 2008 | 24.2°C | 19.3°C | 14.4°C | 31.1°C | 3.0°C | 8 mm | 74% | 4.1 m/s | 3.1 |
| 2007 | 25.1°C | 20.0°C | 15.0°C | 31.6°C | 6.3°C | 3 mm | 71% | 3.8 m/s | 3.4 |
| 2006 | 22.6°C | 18.1°C | 13.5°C | 28.4°C | 2.5°C | 63 mm | 77% | 3.3 m/s | 2.7 |
| 2005 | 23.5°C | 18.8°C | 14.1°C | 28.9°C | 3.7°C | 34 mm | 75% | 3.4 m/s | 2.8 |
| 2004 | 23.0°C | 17.9°C | 12.9°C | 29.5°C | -0.7°C | 23 mm | 71% | 3.5 m/s | 3.2 |
| 2003 | 22.7°C | 17.7°C | 12.8°C | 27.2°C | 4.2°C | 3 mm | 71% | 3.6 m/s | 3.6 |
| 2002 | 22.3°C | 17.7°C | 13.1°C | 27.4°C | 4.8°C | 18 mm | 79% | 3.9 m/s | 3 |
| 2001 | 24.1°C | 19.2°C | 14.3°C | 28.9°C | 4.6°C | 25 mm | 74% | 3.5 m/s | 2.9 |
| 2000 | 21.9°C | 17.0°C | 12.1°C | 27.9°C | 5.2°C | 29 mm | 74% | 3.8 m/s | 2.6 |
| 1999 | 23.7°C | 18.4°C | 13.0°C | 29.3°C | 6.5°C | 12 mm | 66% | 3.9 m/s | 3.3 |
| 1998 | 22.8°C | 18.1°C | 13.4°C | 29.0°C | 2.4°C | 15 mm | 77% | 3.8 m/s | 3.1 |
| 1997 | 22.0°C | 16.7°C | 11.4°C | 29.6°C | 2.5°C | 13 mm | 70% | 3.5 m/s | 3.1 |
| 1996 | 24.0°C | 19.2°C | 14.4°C | 30.4°C | 1.5°C | 23 mm | 76% | 3.4 m/s | 2.9 |
| 1995 | 22.8°C | 18.8°C | 14.8°C | 29.6°C | 6.5°C | 39 mm | 80% | 3.6 m/s | 2.8 |
| 1994 | 24.8°C | 20.5°C | 16.2°C | 30.0°C | 7.7°C | 48 mm | 78% | 3.2 m/s | 2.5 |
| 1993 | 23.8°C | 19.1°C | 14.5°C | 30.3°C | 5.2°C | 61 mm | 74% | 3.5 m/s | 2.6 |
| 1992 | 24.1°C | 19.7°C | 15.3°C | 27.5°C | 7.3°C | 28 mm | 82% | 3.2 m/s | 2.2 |
| 1991 | 22.8°C | 19.2°C | 15.6°C | 29.8°C | 7.0°C | 56 mm | 79% | 3.6 m/s | 2.3 |
| 1990 | 23.6°C | 18.6°C | 13.5°C | 30.7°C | 1.6°C | 12 mm | 70% | 3.7 m/s | 3.2 |
| 1989 ❄️ | 18.1°C | 12.8°C | 7.4°C | 27.8°C | -7.1°C | 52 mm | 71% | 3.7 m/s | 2.8 |
| 1988 | 24.1°C | 19.4°C | 14.8°C | 29.0°C | 6.6°C | 3 mm | 70% | 3.6 m/s | 3.1 |
| 1987 | 24.1°C | 19.3°C | 14.6°C | 31.1°C | 6.9°C | 10 mm | 75% | 3.5 m/s | 2.6 |
| 1986 | 21.2°C | 16.9°C | 12.6°C | 27.6°C | 3.6°C | 88 mm | 79% | 3.2 m/s | 2 |
| 1985 | 22.3°C | 17.4°C | 12.6°C | 30.1°C | 1.6°C | 24 mm | 74% | 3.3 m/s | 2.7 |
| 1984 | 25.6°C | 21.5°C | 17.4°C | 31.0°C | 5.7°C | 48 mm | 82% | 3.8 m/s | 3 |
| 1983 | 21.5°C | 16.0°C | 10.6°C | 32.7°C | -6.0°C | 16 mm | 69% | 3.8 m/s | — |
| 1982 | 22.8°C | 18.3°C | 13.8°C | 30.6°C | 5.3°C | 59 mm | 72% | 3.6 m/s | — |
| 1981 | 24.9°C | 19.7°C | 14.6°C | 30.8°C | 6.9°C | 11 mm | 72% | 3.4 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 23.5°C with lows near 13.9°C (mean 18.7°C), based on 45 years of NASA POWER data.
December averages 30 mm of rainfall in Brownsville, one of the drier months. The wettest on record was 121 mm in 2009.
The hottest December reached 32.7°C in 1983. The coldest dipped to -7.1°C in 1989.
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 23.4°C to 25.5°C and overnight lows from 13.8°C to 15.7°C over the same span.
December is one of the cooler months of the year in Brownsville and one of the drier months, so plan for around 23.5°C daytime highs and 13.9°C at night.
Not quite — December is the 2nd coolest month in Brownsville, averaging 18.7°C.
For December in Brownsville, pack light layers you can adjust through the day, with typical highs of 23.5°C and lows of 13.9°C.
Relative humidity in December averages 75% — moderately humid.
Average wind speed in December is 3.5 m/s. The windiest December on record averaged 4.1 m/s (2008).
The wettest December on record was 2009 with 121 mm. On average, December sees 30 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 Brownsville 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.
